1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 15
6 * GDB now supports printing of ptwrite payloads from the Intel Processor
7 Trace during 'record instruction-history', 'record function-call-history'
8 and all stepping commands. The payload is also accessible in Python as a
9 RecordAuxiliary object. Printing is customizable via a ptwrite filter
10 function in Python. By default, the raw ptwrite payload is printed for
11 each ptwrite that is encountered.
13 * For breakpoints that are created in the 'pending' state, any
14 'thread' or 'task' keywords are parsed at the time the breakpoint is
15 created, rather than at the time the breakpoint becomes non-pending.
17 * Thread-specific breakpoints are only inserted into the program space
18 in which the thread of interest is running. In most cases program
19 spaces are unique for each inferior, so this means that
20 thread-specific breakpoints will usually only be inserted for the
21 inferior containing the thread of interest. The breakpoint will
22 be hit no less than before.
24 * For ARM targets, the offset of the pc in the jmp_buf has been fixed to match
25 glibc 2.20 and later. This should only matter when not using libc probes.
26 This may cause breakage when using an incompatible libc, like uclibc or
27 newlib, or an older glibc.
29 * MTE (Memory Tagging Extension) debugging is now supported on AArch64 baremetal
32 * Remove support (native and remote) for QNX Neutrino (triplet
35 * In a record session, when a forward emulation reaches the end of the reverse
36 history, the warning message has been changed to indicate that the end of the
37 history has been reached. It also specifies that the forward execution can
38 continue, and the recording will also continue.
42 ** Added gdb.record.clear. Clears the trace data of the current recording.
43 This forces re-decoding of the trace for successive commands.
45 * Debugger Adapter Protocol changes
47 ** The "scopes" request will now return a scope holding global
48 variables from the stack frame's compilation unit.
50 ** The "scopes" request will return a "returnValue" scope holding
51 the return value from the latest "stepOut" command, when
56 maintenance info inline-frames [ADDRESS]
57 New command which displays GDB's inline-frame information for the
58 current address, or for ADDRESS if specified. The output identifies
59 inlined frames which start at the specified address.
61 maintenance info blocks [ADDRESS]
62 New command which displays information about all of the blocks at
63 ADDRESS, or at the current address if ADDRESS is not given. Blocks
64 are listed starting at the inner global block out to the most inner
70 This command now supports file-name completion.
72 remove-symbol-file -a ADDRESS
73 The ADDRESS expression can now be a full expression consisting of
74 multiple terms, e.g. 'function + 0x1000' (without quotes),
75 previously only a single term could be given.
84 These commands now require their filename argument to be quoted if
85 it contains white space or quote characters. If the argument
86 contains no such special characters then quoting is not required.
91 Return information about files on the remote system. Like
92 vFile:fstat but takes a filename rather than an open file
97 * The MPX commands "show/set mpx bound" have been deprecated, as Intel
98 listed MPX as removed in 2019.
100 * Building GDB and GDBserver now requires a C++17 compiler.
101 For example, GCC 9 or later.
103 * GDB index now contains information about the main function. This speeds up
104 startup when it is being used for some large binaries.
106 * On hosts where threading is available, DWARF reading is now done in
107 the background, resulting in faster startup. This can be controlled
108 using "maint set dwarf synchronous".
113 Attempting to use both the 'r' and 'b' flags with the disassemble
114 command will now give an error. Previously the 'b' flag would
115 always override the 'r' flag.
119 GDB now generates sparse core files, on systems that support it.
121 maintenance info line-table
122 Add an EPILOGUE-BEGIN column to the output of the command. It indicates
123 if the line is considered the start of the epilgoue, and thus a point at
124 which the frame can be considered destroyed.
126 set unwindonsignal on|off
128 These commands are now aliases for the new set/show unwind-on-signal.
131 This command now gives an error if any unexpected arguments are
132 found after the command.
135 When using the command "list ." in a location that has no debug information
136 or no file loaded, GDB now says that there is no debug information to print
137 lines. This makes it more obvious that there is no information, as opposed
138 to implying there is no inferior loaded.
142 info missing-debug-handler
143 List all the registered missing debug handlers.
145 enable missing-debug-handler LOCUS HANDLER
146 disable missing-debug-handler LOCUS HANDLER
147 Enable or disable a missing debug handler with a name matching the
148 regular expression HANDLER, in LOCUS.
150 LOCUS can be 'global' to operate on global missing debug handler,
151 'progspace' to operate on handlers within the current program space,
152 or can be a regular expression which is matched against the filename
153 of the primary executable in each program space.
155 maintenance info linux-lwps
156 List all LWPs under control of the linux-nat target.
158 set remote thread-options-packet
159 show remote thread-options-packet
160 Set/show the use of the thread options packet.
162 set direct-call-timeout SECONDS
163 show direct-call-timeout
164 set indirect-call-timeout SECONDS
165 show indirect-call-timeout
166 These new settings can be used to limit how long GDB will wait for
167 an inferior function call to complete. The direct timeout is used
168 for inferior function calls from e.g. 'call' and 'print' commands,
169 while the indirect timeout is used for inferior function calls from
170 within a conditional breakpoint expression.
172 The default for the direct timeout is unlimited, while the default
173 for the indirect timeout is 30 seconds.
175 These timeouts will only have an effect for targets that are
176 operating in async mode. For non-async targets the timeouts are
177 ignored, GDB will wait indefinitely for an inferior function to
178 complete, unless interrupted by the user using Ctrl-C.
180 set unwind-on-timeout on|off
181 show unwind-on-timeout
182 These commands control whether GDB should unwind the stack when a
183 timeout occurs during an inferior function call. The default is
184 off, in which case the inferior will remain in the frame where the
185 timeout occurred. When on, GDB will unwind the stack removing the
186 dummy frame that was added for the inferior call, and restoring the
187 inferior state to how it was before the inferior call started.
189 set unwind-on-signal on|off
190 show unwind-on-signal
191 These new commands replaces the existing set/show unwindonsignal. The
192 old command is maintained as an alias.
194 * New features in the GDB remote stub, GDBserver
196 ** The --remote-debug and --event-loop-debug command line options
199 ** The --debug command line option now takes an optional comma
200 separated list of components to emit debug for. The currently
201 supported components are: all, threads, event-loop, and remote.
202 If no components are given then threads is assumed.
204 ** The 'monitor set remote-debug' and 'monitor set event-loop-debug'
205 command have been removed.
207 ** The 'monitor set debug 0|1' command has been extended to take a
208 component name, e.g.: 'monitor set debug COMPONENT off|on'.
209 Possible component names are: all, threads, event-loop, and
214 ** New function gdb.notify_mi(NAME, DATA), that emits custom
215 GDB/MI async notification.
217 ** New read/write attribute gdb.Value.bytes that contains a bytes
218 object holding the contents of this value.
220 ** New module gdb.missing_debug that facilitates dealing with
221 objfiles that are missing any debug information.
223 ** New function gdb.missing_debug.register_handler that can register
224 an instance of a sub-class of gdb.missing_debug.MissingDebugInfo
225 as a handler for objfiles that are missing debug information.
227 ** New class gdb.missing_debug.MissingDebugInfo which can be
228 sub-classed to create handlers for objfiles with missing debug
231 ** Stop events now have a "details" attribute that holds a
232 dictionary that carries the same information as an MI "*stopped"
235 ** New function gdb.interrupt(), that interrupts GDB as if the user
238 ** New gdb.InferiorThread.ptid_string attribute. This read-only
239 attribute contains the string that appears in the 'Target Id'
240 column of the 'info threads' command output.
242 ** It is no longer possible to create new gdb.Progspace object using
243 'gdb.Progspace()', this will result in a TypeError. Progspace
244 objects can still be obtained through calling other API
245 functions, for example 'gdb.current_progspace()'.
247 ** User defined attributes can be added to a gdb.Inferior object,
248 these will be stored in the object's new Inferior.__dict__
251 ** User defined attributes can be added to a gdb.InferiorThread
252 object, these will be stored in the object's new
253 InferiorThread.__dict__ attribute.
255 ** New constants gdb.SYMBOL_TYPE_DOMAIN, gdb.SYMBOL_FUNCTION_DOMAIN,
256 and gdb.SEARCH_*_DOMAIN corresponding to all the existing symbol
257 domains. Symbol lookup can now search in multiple domains at
258 once, and can also narrowly search for just a type or function.
260 * Debugger Adapter Protocol changes
262 ** GDB now emits the "process" event.
264 ** GDB now supports the "cancel" request.
266 ** The "attach" request now supports specifying the program.
268 ** New command "set debug dap-log-level" controls DAP logging.
270 ** The "set debug dap-log-file" command is now documented. This
271 command was available in GDB 14 but not documented.
275 ** New constants SYMBOL_TYPE_DOMAIN, SYMBOL_FUNCTION_DOMAIN, and
276 SEARCH_*_DOMAIN corresponding to all the existing symbol domains.
277 Symbol lookup can now search in multiple domains at once, and can
278 also narrowly search for just a type or function.
282 New stop reason: clone
283 Indicates that a clone system call was executed.
286 Enable/disable optional event reporting, on a per-thread basis.
287 Currently supported options are GDB_THREAD_OPTION_CLONE, to enable
288 clone event reporting, and GDB_THREAD_OPTION_EXIT to enable thread
289 exit event reporting.
291 QThreadOptions in qSupported
292 The qSupported packet allows GDB to inform the stub it supports the
293 QThreadOptions packet, and the qSupported response can contain the
294 set of thread options the remote stub supports.
297 This new packet allows GDB to query the stub about a given address to check
298 if it is tagged or not. Many memory tagging-related GDB commands need to
299 perform this check before they read/write the allocation tag related to an
300 address. Currently, however, this is done through a 'vFile' request to read
301 the file /proc/<PID>/smaps and check if the address is in a region reported
302 as memory tagged. Since not all targets have a notion of what the smaps
303 file is about, this new packet provides a more generic way to perform such
306 *** Changes in GDB 14
308 * GDB now supports the AArch64 Scalable Matrix Extension 2 (SME2), which
309 includes a new 512 bit lookup table register named ZT0.
311 * GDB now supports the AArch64 Scalable Matrix Extension (SME), which includes
312 a new matrix register named ZA, a new thread register TPIDR2 and a new vector
313 length register SVG (streaming vector granule). GDB also supports tracking
314 ZA state across signal frames.
316 Some features are still under development or are dependent on ABI specs that
317 are still in alpha stage. For example, manual function calls with ZA state
318 don't have any special handling, and tracking of SVG changes based on
319 DWARF information is still not implemented, but there are plans to do so in
322 * GDB now recognizes the NO_COLOR environment variable and disables
323 styling according to the spec. See https://no-color.org/.
324 Styling can be re-enabled with "set style enabled on".
326 * The AArch64 'org.gnu.gdb.aarch64.pauth' Pointer Authentication feature string
327 has been deprecated in favor of the 'org.gnu.gdb.aarch64.pauth_v2' feature
330 * GDB now has some support for integer types larger than 64 bits.
332 * Removed targets and native configurations
334 GDB no longer supports AIX 4.x, AIX 5.x and AIX 6.x. The minimum supported
335 AIX version is now AIX 7.1.
337 * Multi-target feature configuration
339 GDB now supports the individual configuration of remote targets' feature
340 sets. Based on the current selection of a target, the commands 'set remote
341 <name>-packet (on|off|auto)' and 'show remote <name>-packet' can be used to
342 configure a target's feature packet and to display its configuration,
345 The individual packet sizes can be configured and shown using the commands
346 ** 'set remote memory-read-packet-size (number of bytes|fixed|limit)'
347 ** 'set remote memory-write-packet-size (number of bytes|fixed|limit)'
348 ** 'show remote memory-read-packet-size'
349 ** 'show remote memory-write-packet-size'.
351 The configuration of the packet itself, as well as the size of a memory-read
352 or memory-write packet applies to the currently selected target (if
353 available). If no target is selected, it applies to future remote
354 connections. Similarly, the show commands print the configuration of the
355 currently selected target. If no remote target is selected, the default
356 configuration for future connections is shown.
358 * GDB has initial built-in support for the Debugger Adapter Protocol.
359 This support requires that GDB be built with Python scripting
362 * For the break command, multiple uses of the 'thread' or 'task'
363 keywords will now give an error instead of just using the thread or
364 task id from the last instance of the keyword. E.g.:
365 break foo thread 1 thread 2
366 will now give an error rather than using 'thread 2'.
368 * For the watch command, multiple uses of the 'task' keyword will now
369 give an error instead of just using the task id from the last
370 instance of the keyword. E.g.:
371 watch my_var task 1 task 2
372 will now give an error rather than using 'task 2'. The 'thread'
373 keyword already gave an error when used multiple times with the
374 watch command, this remains unchanged.
376 * The 'set print elements' setting now helps when printing large arrays.
377 If an array would otherwise exceed max-value-size, but 'print elements'
378 is set such that the size of elements to print is less than or equal
379 to 'max-value-size', GDB will now still print the array, however only
380 'max-value-size' worth of data will be added into the value history.
382 * For both the break and watch commands, it is now invalid to use both
383 the 'thread' and 'task' keywords within the same command. For
384 example the following commnds will now give an error:
385 break foo thread 1 task 1
386 watch var thread 2 task 3
388 * The printf command now accepts a '%V' output format which will
389 format an expression just as the 'print' command would. Print
390 options can be placed withing '[...]' after the '%V' to modify how
391 the value is printed. E.g:
392 printf "%V", some_array
393 printf "%V[-array-indexes on]", some_array
394 will print the array without, or with array indexes included, just
395 as the array would be printed by the 'print' command. This
396 functionality is also available for dprintf when dprintf-style is
399 * When the printf command requires a string to be fetched from the
400 inferior, GDB now uses the existing 'max-value-size' setting to the
401 limit the memory allocated within GDB. The default 'max-value-size'
402 is 64k. To print longer strings you should increase
405 * The Ada 2022 Enum_Rep and Enum_Val attributes are now supported.
407 * The Ada 2022 target name symbol ('@') is now supported by the Ada
410 * The 'list' command now accepts '.' as an argument, which tells GDB to
411 print the location around the point of execution within the current frame.
412 If the inferior hasn't started yet, the command will print around the
413 beginning of the 'main' function.
415 * Using the 'list' command with no arguments in a situation where the
416 command would attempt to list past the end of the file now warns the
417 user that the end of file has been reached, refers the user to the
418 newly added '.' argument
420 * Breakpoints can now be inferior-specific. This is similar to the
421 existing thread-specific breakpoint support. Breakpoint conditions
422 can include the 'inferior' keyword followed by an inferior id (as
423 displayed in the 'info inferiors' output). It is invalid to use the
424 'inferior' keyword with either the 'thread' or 'task' keywords when
425 creating a breakpoint.
427 * New convenience function "$_shell", to execute a shell command and
428 return the result. This lets you run shell commands in expressions.
431 (gdb) p $_shell("true")
433 (gdb) p $_shell("false")
435 (gdb) break func if $_shell("some command") == 0
439 --additional-debug-dirs=PATHs
441 Provide a colon-separated list of additional directories to search for
442 separate debug info. These directories are added to the default value of
443 the 'debug-file-directory' GDB parameter.
447 set debug breakpoint on|off
448 show debug breakpoint
449 Print additional debug messages about breakpoint insertion and removal.
451 maintenance print record-instruction [ N ]
452 Print the recorded information for a given instruction. If N is not given
453 prints how GDB would undo the last instruction executed. If N is negative,
454 prints how GDB would undo the N-th previous instruction, and if N is
455 positive, it prints how GDB will redo the N-th following instruction.
457 maintenance info frame-unwinders
458 List the frame unwinders currently in effect, starting with the highest
461 maintenance wait-for-index-cache
462 Wait until all pending writes to the index cache have completed.
464 set always-read-ctf on|off
466 When off, CTF is only read if DWARF is not present. When on, CTF is
467 read regardless of whether DWARF is present. Off by default.
470 Get main symbol to identify entry point into program.
472 set tui mouse-events [on|off]
473 show tui mouse-events
474 When on (default), mouse clicks control the TUI and can be accessed by
475 Python extensions. When off, mouse clicks are handled by the terminal,
476 enabling terminal-native text selection.
480 ** MI version 1 has been removed.
482 ** mi now reports 'no-history' as a stop reason when hitting the end of the
483 reverse execution history.
485 ** When creating a thread-specific breakpoint using the '-p' option,
486 the -break-insert command would report the 'thread' field twice in
487 the reply. The content of both fields was always identical. This
488 has now been fixed; the 'thread' field will be reported just once
489 for thread-specific breakpoints, or not at all for breakpoints
490 without a thread restriction. The same is also true for the 'task'
491 field of an Ada task-specific breakpoint.
493 ** It is no longer possible to create a thread-specific breakpoint for
494 a thread that doesn't exist using '-break-insert -p ID'. Creating
495 breakpoints for non-existent threads is not allowed when using the
496 CLI, that the MI allowed it was a long standing bug, which has now
499 ** The '--simple-values' argument to the '-stack-list-arguments',
500 '-stack-list-locals', '-stack-list-variables', and '-var-list-children'
501 commands now takes reference types into account: that is, a value is now
502 considered simple if it is neither an array, structure, or union, nor a
503 reference to an array, structure, or union. (Previously all references were
504 considered simple.) Support for this feature can be verified by using the
505 '-list-features' command, which should contain "simple-values-ref-types".
507 ** The -break-insert command now accepts a '-g thread-group-id' option
508 to allow for the creation of inferior-specific breakpoints.
510 ** The bkpt tuple, which appears in breakpoint-created notifications,
511 and in the result of the -break-insert command can now include an
512 optional 'inferior' field for both the main breakpoint, and each
513 location, when the breakpoint is inferior-specific.
517 ** gdb.ThreadExitedEvent added. Emits a ThreadEvent.
519 ** The gdb.unwinder.Unwinder.name attribute is now read-only.
521 ** The name argument passed to gdb.unwinder.Unwinder.__init__ must
522 now be of type 'str' otherwise a TypeError will be raised.
524 ** The gdb.unwinder.Unwinder.enabled attribute can now only accept
525 values of type 'bool'. Changing this attribute will now
526 invalidate GDB's frame-cache, which means GDB will need to
527 rebuild its frame-cache when next required - either with, or
528 without the particular unwinder, depending on how 'enabled' was
531 ** New methods added to the gdb.PendingFrame class. These methods
532 have the same behaviour as the corresponding methods on
533 gdb.Frame. The new methods are:
535 - gdb.PendingFrame.name: Return the name for the frame's
537 - gdb.PendingFrame.is_valid: Return True if the pending frame
539 - gdb.PendingFrame.pc: Return the $pc register value for this
541 - gdb.PendingFrame.language: Return a string containing the
542 language for this frame, or None.
543 - gdb.PendingFrame.find_sal: Return a gdb.Symtab_and_line
544 object for the current location within the pending frame, or
546 - gdb.PendingFrame.block: Return a gdb.Block for the current
547 pending frame, or None.
548 - gdb.PendingFrame.function: Return a gdb.Symbol for the
549 current pending frame, or None.
551 ** The frame-id passed to gdb.PendingFrame.create_unwind_info can
552 now use either an integer or a gdb.Value object for each of its
553 'sp', 'pc', and 'special' attributes.
555 ** A new class gdb.unwinder.FrameId has been added. Instances of
556 this class are constructed with 'sp' (stack-pointer) and 'pc'
557 (program-counter) values, and can be used as the frame-id when
558 calling gdb.PendingFrame.create_unwind_info.
560 ** It is now no longer possible to sub-class the
561 gdb.disassembler.DisassemblerResult type.
563 ** The Disassembler API from the gdb.disassembler module has been
564 extended to include styling support:
566 - The DisassemblerResult class can now be initialized with a list
567 of parts. Each part represents part of the disassembled
568 instruction along with the associated style information. This
569 list of parts can be accessed with the new
570 DisassemblerResult.parts property.
572 - New constants gdb.disassembler.STYLE_* representing all the
573 different styles part of an instruction might have.
575 - New methods DisassembleInfo.text_part and
576 DisassembleInfo.address_part which are used to create the new
577 styled parts of a disassembled instruction.
579 - Changes are backwards compatible, the older API can still be
580 used to disassemble instructions without styling.
582 ** New function gdb.execute_mi(COMMAND, [ARG]...), that invokes a
583 GDB/MI command and returns the output as a Python dictionary.
585 ** New function gdb.block_signals(). This returns a context manager
586 that blocks any signals that GDB needs to handle itself.
588 ** New class gdb.Thread. This is a subclass of threading.Thread
589 that calls gdb.block_signals in its "start" method.
591 ** gdb.parse_and_eval now has a new "global_context" parameter.
592 This can be used to request that the parse only examine global
595 ** gdb.Inferior now has a new "arguments" attribute. This holds the
596 command-line arguments to the inferior, if known.
598 ** gdb.Inferior now has a new "main_name" attribute. This holds the
599 name of the inferior's "main", if known.
601 ** gdb.Inferior now has new methods "clear_env", "set_env", and
602 "unset_env". These can be used to modify the inferior's
603 environment before it is started.
605 ** gdb.Value now has the 'assign' method.
607 ** gdb.Value now has the 'to_array' method. This converts an
608 array-like Value to an array.
610 ** gdb.Progspace now has the new method "objfile_for_address". This
611 returns the gdb.Objfile, if any, that covers a given address.
613 ** gdb.Breakpoint now has an "inferior" attribute. If the
614 Breakpoint object is inferior specific then this attribute holds
615 the inferior-id (an integer). If the Breakpoint object is not
616 inferior specific, then this field contains None. This field can
619 ** gdb.Type now has the "is_array_like" and "is_string_like"
620 methods. These reflect GDB's internal idea of whether a type
621 might be array- or string-like, even if they do not have the
622 corresponding type code.
624 ** gdb.ValuePrinter is a new class that can be used as the base
625 class for the result of applying a pretty-printer. As a base
626 class, it signals to gdb that the printer may implement new
627 pretty-printer methods.
629 ** New attribute Progspace.symbol_file. This attribute holds the
630 gdb.Objfile that corresponds to Progspace.filename (when
631 Progspace.filename is not None), otherwise, this attribute is
634 ** New attribute Progspace.executable_filename. This attribute
635 holds a string containing a file name set by the "exec-file" or
636 "file" commands, or None if no executable file is set. This
637 isn't the exact string passed by the user to these commands; the
638 file name will have been partially resolved to an absolute file
641 ** A new executable_changed event registry is available. This event
642 emits ExecutableChangedEvent objects, which have 'progspace' (a
643 gdb.Progspace) and 'reload' (a Boolean) attributes. This event
644 is emitted when gdb.Progspace.executable_filename changes.
646 ** New event registries gdb.events.new_progspace and
647 gdb.events.free_progspace, these emit NewProgspaceEvent and
648 FreeProgspaceEvent event types respectively. Both of these event
649 types have a single 'progspace' attribute, which is the
650 gdb.Progspace that is either being added to GDB, or removed from
653 ** gdb.LazyString now implements the __str__ method.
655 ** New method gdb.Frame.static_link that returns the outer frame
656 of a nested function frame.
658 *** Changes in GDB 13
660 * MI version 1 is deprecated, and will be removed in GDB 14.
662 * GDB now supports dumping memory tag data for AArch64 MTE. It also supports
663 reading memory tag data for AArch64 MTE from core files generated by
664 the gcore command or the Linux kernel.
666 When a process uses memory-mapped pages protected by memory tags (for
667 example, AArch64 MTE), this additional information will be recorded in
668 the core file in the event of a crash or if GDB generates a core file
669 from the current process state. GDB will show this additional information
670 automatically, or through one of the memory-tag subcommands.
672 * Scheduler-locking and new threads
674 When scheduler-locking is in effect, only the current thread may run
675 when the inferior is resumed. However, previously, new threads
676 created by the resumed thread would still be able to run free. Now,
677 they are held stopped.
679 * "info breakpoints" now displays enabled breakpoint locations of
680 disabled breakpoints as in the "y-" state. For example:
682 (gdb) info breakpoints
683 Num Type Disp Enb Address What
684 1 breakpoint keep n <MULTIPLE>
685 1.1 y- 0x00000000000011b6 in ...
686 1.2 y- 0x00000000000011c2 in ...
687 1.3 n 0x00000000000011ce in ...
689 * Support for Thread Local Storage (TLS) variables on FreeBSD arm and
690 aarch64 architectures.
692 * GDB now supports hardware watchpoints on FreeBSD/Aarch64.
694 * Remove support for building against Python 2, it is now only possible to
695 build GDB against Python 3.
697 * DBX mode has been removed.
699 * GDB now honours the DWARF prologue_end line-table entry flag the compiler can
700 emit to indicate where a breakpoint should be placed to break in a function
703 * Completion now also offers "NUMBER" for "set" commands that accept
704 a numeric argument and the "unlimited" keyword. For example:
706 (gdb) set width <TAB>
711 (gdb) complete set width
715 * Disassembler styling using libopcodes. GDB now supports
716 disassembler styling using libopcodes. This is only available for
717 some targets (currently x86 and RISC-V). For unsupported targets
718 Python Pygments is still used. For supported targets, libopcodes
719 styling is used by default.
721 * The Windows native target now supports target async.
723 * gdb now supports zstd compressed debug sections (ELFCOMPRESS_ZSTD) for ELF.
725 * The format of 'disassemble /r' and 'record instruction-history /r'
726 has changed. The instruction bytes could now be grouped together,
727 and displayed in the endianness of the instruction. This is the
728 same layout as used by GNU objdump when disassembling.
730 There is now 'disassemble /b' and 'record instruction-history /b'
731 which will always display the instructions bytes one at a time in
732 memory order, that is, the byte at the lowest address first.
734 For both /r and /b GDB is now better at using whitespace in order to
735 align the disassembled instruction text.
737 * The TUI no longer styles the source and assembly code highlighted by
738 the current position indicator by default. You can however
739 re-enable styling using the new "set style tui-current-position"
742 * New convenience variable $_inferior_thread_count contains the number
743 of live threads in the current inferior.
745 * When a breakpoint with multiple code locations is hit, GDB now prints
746 the code location using the syntax <breakpoint_number>.<location_number>
748 Thread 1 "zeoes" hit Breakpoint 2.3, some_func () at zeoes.c:8
750 * When a breakpoint is hit, GDB now sets the convenience variables $_hit_bpnum
751 and $_hit_locno to the hit breakpoint number and code location number.
752 This allows to disable the last hit breakpoint using
753 (gdb) disable $_hit_bpnum
754 or disable only the specific breakpoint code location using
755 (gdb) disable $_hit_bpnum.$_hit_locno
756 These commands can be used inside the command list of a breakpoint to
757 automatically disable the just encountered breakpoint (or the just
758 encountered specific breakpoint code location).
759 When a breakpoint has only one location, $_hit_locno is set to 1 so that
760 (gdb) disable $_hit_bpnum.$_hit_locno
762 (gdb) disable $_hit_bpnum
763 are both disabling the breakpoint.
767 maintenance set ignore-prologue-end-flag on|off
768 maintenance show ignore-prologue-end-flag
769 This setting, which is off by default, controls whether GDB ignores the
770 PROLOGUE-END flag from the line-table when skipping prologue. This can be
771 used to force GDB to use prologue analyzers if the line-table is constructed
772 from erroneous debug information.
774 set print nibbles [on|off]
776 This controls whether the 'print/t' command will display binary values
777 in groups of four bits, known as "nibbles". The default is 'off'.
779 maintenance set libopcodes-styling on|off
780 maintenance show libopcodes-styling
781 These can be used to force off libopcodes based styling, the Python
782 Pygments styling will then be used instead.
784 set style disassembler comment
785 show style disassembler comment
786 set style disassembler immediate
787 show style disassembler immediate
788 set style disassembler mnemonic
789 show style disassembler mnemonic
790 set style disassembler register
791 show style disassembler register
792 set style disassembler address
793 show style disassembler address
794 set style disassembler symbol
795 show style disassembler symbol
796 For targets that support libopcodes based styling, these settings
797 control how various aspects of the disassembler output are styled.
798 The 'disassembler address' and 'disassembler symbol' styles are
799 aliases for the 'address' and 'function' styles respectively.
801 maintenance print frame-id [ LEVEL ]
802 Print GDB's internal frame-id for the frame at LEVEL. If LEVEL is
803 not given, then print the frame-id for the currently selected frame.
805 set debug infcall on|off
807 Print additional debug messages about inferior function calls.
809 set debug solib on|off
811 Print additional debug messages about shared library handling.
813 set style tui-current-position [on|off]
814 Whether to style the source and assembly code highlighted by the
815 TUI's current position indicator. The default is off.
817 set print characters LIMIT
818 show print characters
819 This new setting is like 'set print elements', but controls how many
820 characters of a string are printed. This functionality used to be
821 covered by 'set print elements', but it can be controlled separately
822 now. LIMIT can be set to a numerical value to request that particular
823 character count, to 'unlimited' to print all characters of a string,
824 or to 'elements', which is also the default, to follow the setting of
825 'set print elements' as it used to be.
827 print -characters LIMIT
828 This new option to the 'print' command has the same effect as a temporary
829 use of 'set print characters'.
833 document user-defined
834 It is now possible to document user-defined aliases.
835 When a user-defined alias is documented, the help and apropos commands
836 use the provided documentation instead of the documentation of the
838 Documenting a user-defined alias is particularly useful when the alias
839 is a set of nested 'with' commands to avoid showing the help of
840 the with command for an alias that will in fact launch the
841 last command given in the nested commands.
843 maintenance info line-table
844 Add a PROLOGUE-END column to the output which indicates that an
845 entry corresponds to an address where a breakpoint should be placed
846 to be at the first instruction past a function's prologue.
850 set debug aix-solib on|off
852 set debug solib-frv on|off
854 Removed in favor of "set/show debug solib".
856 maintenance info program-spaces
857 This command now includes a 'Core File' column which indicates the
858 name of the core file associated with each program space.
862 GNU/Linux/LoongArch (gdbserver) loongarch*-*-linux*
864 GNU/Linux/CSKY (gdbserver) csky*-*linux*
870 ** The async record stating the stopped reason 'breakpoint-hit' now
871 contains an optional field locno giving the code location number
872 when the breakpoint has multiple code locations.
876 ** GDB will now reformat the doc string for gdb.Command and
877 gdb.Parameter sub-classes to remove unnecessary leading
878 whitespace from each line before using the string as the help
881 ** New function gdb.format_address(ADDRESS, PROGSPACE, ARCHITECTURE),
882 that formats ADDRESS as 'address <symbol+offset>', where symbol is
883 looked up in PROGSPACE, and ARCHITECTURE is used to format address.
884 This is the same format that GDB uses when printing address, symbol,
885 and offset information from the disassembler.
887 ** New function gdb.current_language that returns the name of the
888 current language. Unlike gdb.parameter('language'), this will
891 ** New method gdb.Frame.language that returns the name of the
894 ** New Python API for wrapping GDB's disassembler:
896 - gdb.disassembler.register_disassembler(DISASSEMBLER, ARCH).
897 DISASSEMBLER is a sub-class of gdb.disassembler.Disassembler.
898 ARCH is either None or a string containing a bfd architecture
899 name. DISASSEMBLER is registered as a disassembler for
900 architecture ARCH, or for all architectures if ARCH is None.
901 The previous disassembler registered for ARCH is returned, this
902 can be None if no previous disassembler was registered.
904 - gdb.disassembler.Disassembler is the class from which all
905 disassemblers should inherit. Its constructor takes a string,
906 a name for the disassembler, which is currently only used in
907 some debug output. Sub-classes should override the __call__
908 method to perform disassembly, invoking __call__ on this base
909 class will raise an exception.
911 - gdb.disassembler.DisassembleInfo is the class used to describe
912 a single disassembly request from GDB. An instance of this
913 class is passed to the __call__ method of
914 gdb.disassembler.Disassembler and has the following read-only
915 attributes: 'address', and 'architecture', as well as the
916 following method: 'read_memory'.
918 - gdb.disassembler.builtin_disassemble(INFO, MEMORY_SOURCE),
919 calls GDB's builtin disassembler on INFO, which is a
920 gdb.disassembler.DisassembleInfo object. MEMORY_SOURCE is
921 optional, its default value is None. If MEMORY_SOURCE is not
922 None then it must be an object that has a 'read_memory' method.
924 - gdb.disassembler.DisassemblerResult is a class that can be used
925 to wrap the result of a call to a Disassembler. It has
926 read-only attributes 'length' and 'string'.
928 ** gdb.Objfile now has an attribute named "is_file". This is True
929 if the objfile comes from a file, and False otherwise.
931 ** New function gdb.print_options that returns a dictionary of the
932 prevailing print options, in the form accepted by
933 gdb.Value.format_string.
935 ** gdb.Value.format_string now uses the format provided by 'print',
936 if it is called during a 'print' or other similar operation.
938 ** gdb.Value.format_string now accepts the 'summary' keyword. This
939 can be used to request a shorter representation of a value, the
940 way that 'set print frame-arguments scalars' does.
942 ** New Python type gdb.BreakpointLocation.
943 The new attribute 'locations' of gdb.Breakpoint returns a list of
944 gdb.BreakpointLocation objects specifying the locations where the
945 breakpoint is inserted into the debuggee.
947 ** The gdb.register_window_type method now restricts the set of
948 acceptable window names. The first character of a window's name
949 must start with a character in the set [a-zA-Z], every subsequent
950 character of a window's name must be in the set [-_.a-zA-Z0-9].
952 * New features in the GDB remote stub, GDBserver
954 ** GDBserver is now supported on LoongArch GNU/Linux.
956 ** GDBserver is now supported on CSKY GNU/Linux.
958 * LoongArch floating-point support
960 GDB now supports floating-point on LoongArch GNU/Linux.
962 * AMD GPU ROCm debugging support
964 GDB now supports debugging programs offloaded to AMD GPUs using the ROCm
967 *** Changes in GDB 12
969 * DBX mode is deprecated, and will be removed in GDB 13
971 * GDB 12 is the last release of GDB that will support building against
972 Python 2. From GDB 13, it will only be possible to build GDB itself
973 with Python 3 support.
975 * The disable-randomization setting now works on Windows.
977 * Improved C++ template support
979 GDB now treats functions/types involving C++ templates like it does function
980 overloads. Users may omit parameter lists to set breakpoints on families of
981 template functions, including types/functions composed of multiple template types:
983 (gdb) break template_func(template_1, int)
985 The above will set breakpoints at every function `template_func' where
986 the first function parameter is any template type named `template_1' and
987 the second function parameter is `int'.
989 TAB completion also gains similar improvements.
991 * The FreeBSD native target now supports async mode.
997 Enable or disable multithreaded symbol loading. This is enabled
998 by default, but passing --disable-threading or --enable-threading=no
999 to configure will disable it.
1001 Disabling this can cause a performance penalty when there are a lot of
1002 symbols to load, but is useful for debugging purposes.
1006 maint set backtrace-on-fatal-signal on|off
1007 maint show backtrace-on-fatal-signal
1008 This setting is 'on' by default. When 'on' GDB will print a limited
1009 backtrace to stderr in the situation where GDB terminates with a
1010 fatal signal. This only supported on some platforms where the
1011 backtrace and backtrace_symbols_fd functions are available.
1013 set source open on|off
1015 This setting, which is on by default, controls whether GDB will try
1016 to open source code files. Switching this off will stop GDB trying
1017 to open and read source code files, which can be useful if the files
1018 are located over a slow network connection.
1022 These are now deprecated aliases for "set max-value-size" and
1023 "show max-value-size".
1025 task apply [all | TASK-IDS...] [FLAG]... COMMAND
1026 Like "thread apply", but applies COMMAND to Ada tasks.
1029 Watchpoints can now be restricted to a specific Ada task.
1031 maint set internal-error backtrace on|off
1032 maint show internal-error backtrace
1033 maint set internal-warning backtrace on|off
1034 maint show internal-warning backtrace
1035 GDB can now print a backtrace of itself when it encounters either an
1036 internal-error, or an internal-warning. This is on by default for
1037 internal-error and off by default for internal-warning.
1040 Deprecated and replaced by "set logging enabled on|off".
1042 set logging enabled on|off
1043 show logging enabled
1044 These commands set or show whether logging is enabled or disabled.
1047 You can now exit GDB by using the new command "exit", in addition to
1048 the existing "quit" command.
1050 set debug threads on|off
1052 Print additional debug messages about thread creation and deletion.
1054 set debug linux-nat on|off
1055 show debug linux-nat
1056 These new commands replaced the old 'set debug lin-lwp' and 'show
1057 debug lin-lwp' respectively. Turning this setting on prints debug
1058 messages relating to GDB's handling of native Linux inferiors.
1060 maint flush source-cache
1061 Flush the contents of the source code cache.
1063 maint set gnu-source-highlight enabled on|off
1064 maint show gnu-source-highlight enabled
1065 Whether GDB should use the GNU Source Highlight library for adding
1066 styling to source code. When off, the library will not be used, even
1067 when available. When GNU Source Highlight isn't used, or can't add
1068 styling to a particular source file, then the Python Pygments
1069 library will be used instead.
1071 set suppress-cli-notifications (on|off)
1072 show suppress-cli-notifications
1073 This controls whether printing the notifications is suppressed for CLI.
1074 CLI notifications occur when you change the selected context
1075 (i.e., the current inferior, thread and/or the frame), or when
1076 the program being debugged stops (e.g., because of hitting a
1077 breakpoint, completing source-stepping, an interrupt, etc.).
1079 set style disassembler enabled on|off
1080 show style disassembler enabled
1081 If GDB is compiled with Python support, and the Python Pygments
1082 package is available, then, when this setting is on, disassembler
1083 output will have styling applied.
1085 set ada source-charset
1086 show ada source-charset
1087 Set the character set encoding that is assumed for Ada symbols. Valid
1088 values for this follow the values that can be passed to the GNAT
1089 compiler via the '-gnati' option. The default is ISO-8859-1.
1095 These are the new names for the old 'layout', 'focus', 'refresh',
1096 and 'winheight' tui commands respectively. The old names still
1097 exist as aliases to these new commands.
1101 The new command 'tui window width', and the alias 'winwidth' allow
1102 the width of a tui window to be adjusted when windows are laid out
1105 set debug tui on|off
1107 Control the display of debug output about GDB's tui.
1112 Printing of floating-point values with base-modifying formats like
1113 /x has been changed to display the underlying bytes of the value in
1114 the desired base. This was GDB's documented behavior, but was never
1115 implemented correctly.
1118 This command can now print a reply, if the reply includes
1119 non-printable characters. Any non-printable characters are printed
1120 as escaped hex, e.g. \x?? where '??' is replaces with the value of
1121 the non-printable character.
1124 The clone-inferior command now ensures that the TTY, CMD and ARGS
1125 settings are copied from the original inferior to the new one.
1126 All modifications to the environment variables done using the 'set
1127 environment' or 'unset environment' commands are also copied to the new
1130 set debug lin-lwp on|off
1132 These commands have been removed from GDB. The new command 'set
1133 debug linux-nat' and 'show debug linux-nat' should be used
1137 This command now includes information about the width of the tui
1138 windows in its output.
1144 These commands are now aliases for the 'tui layout', 'tui focus',
1145 'tui refresh', and 'tui window height' commands respectively.
1147 * GDB's Ada parser now supports an extension for specifying the exact
1148 byte contents of a floating-point literal. This can be useful for
1149 setting floating-point registers to a precise value without loss of
1150 precision. The syntax is an extension of the based literal syntax.
1151 Use, e.g., "16lf#0123abcd#" -- the number of "l"s controls the width
1152 of the floating-point type, and the "f" is the marker for floating
1157 ** The '-add-inferior' with no option flags now inherits the
1158 connection of the current inferior, this restores the behaviour of
1159 GDB as it was prior to GDB 10.
1161 ** The '-add-inferior' command now accepts a '--no-connection'
1162 option, which causes the new inferior to start without a
1165 ** The default version of the MI interpreter is now 4 (-i=mi4).
1167 ** The "script" field in breakpoint output (which is syntactically
1168 incorrect in MI 3 and below) has changed in MI 4 to become a list.
1169 This affects the following commands and events:
1173 - =breakpoint-created
1174 - =breakpoint-modified
1176 The -fix-breakpoint-script-output command can be used to enable
1177 this behavior with previous MI versions.
1181 GNU/Linux/LoongArch loongarch*-*-linux*
1189 ** New function gdb.add_history(), which takes a gdb.Value object
1190 and adds the value it represents to GDB's history list. An
1191 integer, the index of the new item in the history list, is
1194 ** New function gdb.history_count(), which returns the number of
1195 values in GDB's value history.
1197 ** New gdb.events.gdb_exiting event. This event is called with a
1198 gdb.GdbExitingEvent object which has the read-only attribute
1199 'exit_code', which contains the value of the GDB exit code. This
1200 event is triggered once GDB decides it is going to exit, but
1201 before GDB starts to clean up its internal state.
1203 ** New function gdb.architecture_names(), which returns a list
1204 containing all of the possible Architecture.name() values. Each
1207 ** New function gdb.Architecture.integer_type(), which returns an
1208 integer type given a size and a signed-ness.
1210 ** New gdb.TargetConnection object type that represents a connection
1211 (as displayed by the 'info connections' command). A sub-class,
1212 gdb.RemoteTargetConnection, is used to represent 'remote' and
1213 'extended-remote' connections.
1215 ** The gdb.Inferior type now has a 'connection' property which is an
1216 instance of gdb.TargetConnection, the connection used by this
1217 inferior. This can be None if the inferior has no connection.
1219 ** New 'gdb.events.connection_removed' event registry, which emits a
1220 'gdb.ConnectionEvent' when a connection is removed from GDB.
1221 This event has a 'connection' property, a gdb.TargetConnection
1222 object for the connection being removed.
1224 ** New gdb.connections() function that returns a list of all
1225 currently active connections.
1227 ** New gdb.RemoteTargetConnection.send_packet(PACKET) method. This
1228 is equivalent to the existing 'maint packet' CLI command; it
1229 allows a user specified packet to be sent to the remote target.
1231 ** New function gdb.host_charset(), returns a string, which is the
1232 name of the current host charset.
1234 ** New gdb.set_parameter(NAME, VALUE). This sets the gdb parameter
1237 ** New gdb.with_parameter(NAME, VALUE). This returns a context
1238 manager that temporarily sets the gdb parameter NAME to VALUE,
1239 then resets it when the context is exited.
1241 ** The gdb.Value.format_string method now takes a 'styling'
1242 argument, which is a boolean. When true, the returned string can
1243 include escape sequences to apply styling. The styling will only
1244 be present if styling is otherwise turned on in GDB (see 'help
1245 set styling'). When false, which is the default if the argument
1246 is not given, then no styling is applied to the returned string.
1248 ** New read-only attribute gdb.InferiorThread.details, which is
1249 either a string, containing additional, target specific thread
1250 state information, or None, if there is no such additional
1253 ** New read-only attribute gdb.Type.is_scalar, which is True for
1254 scalar types, and False for all other types.
1256 ** New read-only attribute gdb.Type.is_signed. This attribute
1257 should only be read when Type.is_scalar is True, and will be True
1258 for signed types, and False for all other types. Attempting to
1259 read this attribute for non-scalar types will raise a ValueError.
1261 ** It is now possible to add GDB/MI commands implemented in Python.
1263 * New features in the GDB remote stub, GDBserver
1265 ** GDBserver is now supported on OpenRISC GNU/Linux.
1267 * New native configurations
1269 GNU/Linux/OpenRISC or1k*-*-linux*
1271 *** Changes in GDB 11
1273 * The 'set disassembler-options' command now supports specifying options
1276 * GDB now supports general memory tagging functionality if the underlying
1277 architecture supports the proper primitives and hooks. Currently this is
1278 enabled only for AArch64 MTE.
1282 - Additional information when the inferior crashes with a SIGSEGV caused by
1283 a memory tag violation.
1285 - A new modifier 'm' for the "x" command, which displays allocation tags for a
1286 particular memory range.
1288 - Display of memory tag mismatches by "print", for addresses and
1289 pointers, if memory tagging is supported by the architecture.
1291 * Building GDB now requires GMP (The GNU Multiple Precision Arithmetic
1296 ** '-break-insert --qualified' and '-dprintf-insert --qualified'
1298 The MI -break-insert and -dprintf-insert commands now support a
1299 new "--qualified" option that makes GDB interpret a specified
1300 function name as a complete fully-qualified name. This is the
1301 equivalent of the CLI's "break -qualified" and "dprintf
1304 ** '-break-insert --force-condition' and '-dprintf-insert --force-condition'
1306 The MI -break-insert and -dprintf-insert commands now support a
1307 '--force-condition' flag to forcibly define a condition even when
1308 the condition is invalid at all locations of the breakpoint. This
1309 is equivalent to the '-force-condition' flag of the CLI's "break"
1312 ** '-break-condition --force'
1314 The MI -break-condition command now supports a '--force' flag to
1315 forcibly define a condition even when the condition is invalid at
1316 all locations of the selected breakpoint. This is equivalent to
1317 the '-force' flag of the CLI's "cond" command.
1319 ** '-file-list-exec-source-files [--group-by-objfile]
1320 [--basename | --dirname]
1323 The existing -file-list-exec-source-files command now takes an
1324 optional REGEXP which is used to filter the source files that are
1325 included in the results.
1327 By default REGEXP is matched against the full filename of the
1328 source file. When one of --basename or --dirname is given then
1329 REGEXP is only matched against the specified part of the full
1332 When the optional --group-by-objfile flag is used the output
1333 format is changed, the results are now a list of object files
1334 (executable and libraries) with the source files that are
1335 associated with each object file.
1337 The results from -file-list-exec-source-files now include a
1338 'debug-fully-read' field which takes the value 'true' or 'false'.
1339 A 'true' value indicates the source file is from a compilation
1340 unit that has had its debug information fully read in by GDB, a
1341 value of 'false' indicates GDB has only performed a partial scan
1342 of the debug information so far.
1344 * GDB now supports core file debugging for x86_64 Cygwin programs.
1346 * GDB will now look for the .gdbinit file in a config directory before
1347 looking for ~/.gdbinit. The file is searched for in the following
1348 locations: $XDG_CONFIG_HOME/gdb/gdbinit, $HOME/.config/gdb/gdbinit,
1349 $HOME/.gdbinit. On Apple hosts the search order is instead:
1350 $HOME/Library/Preferences/gdb/gdbinit, $HOME/.gdbinit.
1352 * GDB now supports fixed point types which are described in DWARF
1353 as base types with a fixed-point encoding. Additionally, support
1354 for the DW_AT_GNU_numerator and DW_AT_GNU_denominator has also
1357 For Ada, this allows support for fixed point types without requiring
1358 the use of the GNAT encoding (based on information added to the type's
1359 name following a GNAT-specific format).
1361 * GDB will now load and process commands from ~/.config/gdb/gdbearlyinit
1362 or ~/.gdbearlyinit if these files are present. These files are
1363 processed earlier than any of the other initialization files and
1364 can affect parts of GDB's startup that previously had already been
1365 completed before the initialization files were read, for example
1366 styling of the initial GDB greeting.
1368 * GDB now has two new options "--early-init-command" and
1369 "--early-init-eval-command" with corresponding short options "-eix"
1370 and "-eiex" that allow options (that would normally appear in a
1371 gdbearlyinit file) to be passed on the command line.
1373 * For RISC-V targets, the target feature "org.gnu.gdb.riscv.vector" is
1374 now understood by GDB, and can be used to describe the vector
1375 registers of a target. The precise requirements of this register
1376 feature are documented in the GDB manual.
1378 * For ARM targets, the "org.gnu.gdb.arm.m-profile-mve" feature is now
1379 supported by GDB and describes a new VPR register from the ARM MVE
1380 (Helium) extension. See the GDB manual for more information.
1384 ** TUI windows now support mouse actions. The mouse wheel scrolls
1385 the appropriate window.
1387 ** Key combinations that do not have a specific action on the
1388 focused window are passed to GDB. For example, you now can use
1389 Ctrl-Left/Ctrl-Right to move between words in the command window
1390 regardless of which window is in focus. Previously you would
1391 need to focus on the command window for such key combinations to
1396 set debug event-loop
1397 show debug event-loop
1398 Control the display of debug output about GDB's event loop.
1400 set print memory-tag-violations
1401 show print memory-tag-violations
1402 Control whether to display additional information about memory tag violations
1403 when printing pointers and addresses. Architecture support for memory
1404 tagging is required for this option to have an effect.
1406 maintenance flush symbol-cache
1407 maintenance flush register-cache
1408 These new commands are equivalent to the already existing commands
1409 'maintenance flush-symbol-cache' and 'flushregs' respectively.
1411 maintenance flush dcache
1412 A new command to flush the dcache.
1414 maintenance info target-sections
1415 Print GDB's internal target sections table.
1417 maintenance info jit
1418 Print the JIT code objects in the inferior known to GDB.
1420 memory-tag show-logical-tag POINTER
1421 Print the logical tag for POINTER.
1422 memory-tag with-logical-tag POINTER TAG
1423 Print POINTER with logical tag TAG.
1424 memory-tag show-allocation-tag ADDRESS
1425 Print the allocation tag for ADDRESS.
1426 memory-tag set-allocation-tag ADDRESS LENGTH TAGS
1427 Set the allocation tag for [ADDRESS, ADDRESS + LENGTH) to TAGS.
1428 memory-tag check POINTER
1429 Validate that POINTER's logical tag matches the allocation tag.
1431 set startup-quietly on|off
1432 show startup-quietly
1433 When 'on', this causes GDB to act as if "-silent" were passed on the
1434 command line. This command needs to be added to an early
1435 initialization file (e.g. ~/.config/gdb/gdbearlyinit) in order to
1438 set print type hex on|off
1440 When 'on', the 'ptype' command uses hexadecimal notation to print sizes
1441 and offsets of struct members. When 'off', decimal notation is used.
1443 set python ignore-environment on|off
1444 show python ignore-environment
1445 When 'on', this causes GDB's builtin Python to ignore any
1446 environment variables that would otherwise affect how Python
1447 behaves. This command needs to be added to an early initialization
1448 file (e.g. ~/.config/gdb/gdbearlyinit) in order to affect GDB.
1450 set python dont-write-bytecode auto|on|off
1451 show python dont-write-bytecode
1452 When 'on', this causes GDB's builtin Python to not write any
1453 byte-code (.pyc files) to disk. This command needs to be added to
1454 an early initialization file (e.g. ~/.config/gdb/gdbearlyinit) in
1455 order to affect GDB. When 'off' byte-code will always be written.
1456 When set to 'auto' (the default) Python will check the
1457 PYTHONDONTWRITEBYTECODE environment variable.
1461 break [PROBE_MODIFIER] [LOCATION] [thread THREADNUM]
1462 [-force-condition] [if CONDITION]
1463 This command would previously refuse setting a breakpoint if the
1464 CONDITION expression is invalid at a location. It now accepts and
1465 defines the breakpoint if there is at least one location at which
1466 the CONDITION is valid. The locations for which the CONDITION is
1467 invalid, are automatically disabled. If CONDITION is invalid at all
1468 of the locations, setting the breakpoint is still rejected. However,
1469 the '-force-condition' flag can be used in this case for forcing GDB to
1470 define the breakpoint, making all the current locations automatically
1471 disabled. This may be useful if the user knows the condition will
1472 become meaningful at a future location, e.g. due to a shared library
1475 condition [-force] N COND
1476 The behavior of this command is changed the same way for the 'break'
1477 command as explained above. The '-force' flag can be used to force
1478 GDB into defining the condition even when COND is invalid for all the
1479 current locations of breakpoint N.
1482 maintenance flush-symbol-cache
1483 These commands are deprecated in favor of the new commands
1484 'maintenance flush register-cache' and 'maintenance flush
1485 symbol-cache' respectively.
1487 set style version foreground COLOR
1488 set style version background COLOR
1489 set style version intensity VALUE
1490 Control the styling of GDB's version number text.
1493 When the ID parameter is omitted, then this command prints information
1494 about the current inferior. When the ID parameter is present, the
1495 behavior of the command is unchanged and have the inferior ID become
1496 the current inferior.
1498 maintenance info sections
1499 The ALLOBJ keyword has been replaced with an -all-objects command
1500 line flag. It is now possible to filter which sections are printed
1501 even when -all-objects is passed.
1503 ptype[/FLAGS] TYPE | EXPRESSION
1504 The 'ptype' command has two new flags. When '/x' is set, hexadecimal
1505 notation is used when printing sizes and offsets of struct members.
1506 When '/d' is set, decimal notation is used when printing sizes and
1507 offsets of struct members. Default behavior is given by 'show print
1511 The info sources command output has been restructured. The results
1512 are now based around a list of objfiles (executable and libraries),
1513 and for each objfile the source files that are part of that objfile
1516 * Removed targets and native configurations
1518 ARM Symbian arm*-*-symbianelf*
1520 * New remote packets
1523 Request the remote to send allocation tags for a particular memory range.
1525 Request the remote to store the specified allocation tags to the requested
1530 ** Improved support for rvalue reference values:
1531 TYPE_CODE_RVALUE_REF is now exported as part of the API and the
1532 value-referenced-value procedure now handles rvalue reference
1535 ** New procedures for obtaining value variants:
1536 value-reference-value, value-rvalue-reference-value and
1539 ** Temporary breakpoints can now be created with make-breakpoint and
1540 tested for using breakpoint-temporary?.
1544 ** Inferior objects now contain a read-only 'connection_num' attribute that
1545 gives the connection number as seen in 'info connections' and
1548 ** New method gdb.Frame.level() which returns the stack level of the
1551 ** New method gdb.PendingFrame.level() which returns the stack level
1552 of the frame object.
1554 ** When hitting a catchpoint, the Python API will now emit a
1555 gdb.BreakpointEvent rather than a gdb.StopEvent. The
1556 gdb.Breakpoint attached to the event will have type BP_CATCHPOINT.
1558 ** Python TUI windows can now receive mouse click events. If the
1559 Window object implements the click method, it is called for each
1560 mouse click event in this window.
1562 *** Changes in GDB 10
1564 * There are new feature names for ARC targets: "org.gnu.gdb.arc.core"
1565 and "org.gnu.gdb.arc.aux". The old names are still supported but
1566 must be considered obsolete. They will be deprecated after some
1569 * Help and apropos commands will now show the documentation of a
1570 command only once, even if that command has one or more aliases.
1571 These commands now show the command name, then all of its aliases,
1572 and finally the description of the command.
1574 * 'help aliases' now shows only the user defined aliases. GDB predefined
1575 aliases are shown together with their aliased command.
1577 * GDB now supports debuginfod, an HTTP server for distributing ELF/DWARF
1578 debugging information as well as source code.
1580 When built with debuginfod, GDB can automatically query debuginfod
1581 servers for the separate debug files and source code of the executable
1584 To build GDB with debuginfod, pass --with-debuginfod to configure (this
1585 requires libdebuginfod, the debuginfod client library).
1587 debuginfod is distributed with elfutils, starting with version 0.178.
1589 You can get the latest version from https://sourceware.org/elfutils.
1591 * Multi-target debugging support
1593 GDB now supports debugging multiple target connections
1594 simultaneously. For example, you can now have each inferior
1595 connected to different remote servers running in different machines,
1596 or have one inferior debugging a local native process, an inferior
1597 debugging a core dump, etc.
1599 This support is experimental and comes with some limitations -- you
1600 can only resume multiple targets simultaneously if all targets
1601 support non-stop mode, and all remote stubs or servers must support
1602 the same set of remote protocol features exactly. See also "info
1603 connections" and "add-inferior -no-connection" below, and "maint set
1604 target-non-stop" in the user manual.
1606 * New features in the GDB remote stub, GDBserver
1608 ** GDBserver is now supported on ARC GNU/Linux.
1610 ** GDBserver is now supported on RISC-V GNU/Linux.
1612 ** GDBserver no longer supports these host triplets:
1614 i[34567]86-*-lynxos*
1623 i[34567]86-*-mingw32ce*
1625 * Debugging MS-Windows processes now sets $_exitsignal when the
1626 inferior is terminated by a signal, instead of setting $_exitcode.
1628 * Multithreaded symbol loading has now been enabled by default on systems
1629 that support it (see entry for GDB 9, below), providing faster
1630 performance for programs with many symbols.
1632 * The $_siginfo convenience variable now also works on Windows targets,
1633 and will display the EXCEPTION_RECORD of the last handled exception.
1635 * TUI windows can now be arranged horizontally.
1637 * The command history filename can now be set to the empty string
1638 either using 'set history filename' or by setting 'GDBHISTFILE=' in
1639 the environment. The effect of setting this filename to the empty
1640 string is that GDB will not try to load any previous command
1643 * On Windows targets, it is now possible to debug 32-bit programs with a
1648 set exec-file-mismatch -- Set exec-file-mismatch handling (ask|warn|off).
1649 show exec-file-mismatch -- Show exec-file-mismatch handling (ask|warn|off).
1650 Set or show the option 'exec-file-mismatch'. When GDB attaches to a
1651 running process, this new option indicates whether to detect
1652 a mismatch between the current executable file loaded by GDB and the
1653 executable file used to start the process. If 'ask', the default,
1654 display a warning and ask the user whether to load the process
1655 executable file; if 'warn', just display a warning; if 'off', don't
1656 attempt to detect a mismatch.
1658 tui new-layout NAME WINDOW WEIGHT [WINDOW WEIGHT]...
1659 Define a new TUI layout, specifying its name and the windows that
1662 maintenance print xml-tdesc [FILE]
1663 Prints the current target description as an XML document. If the
1664 optional FILE is provided (which is an XML target description) then
1665 the target description is read from FILE into GDB, and then
1668 maintenance print core-file-backed-mappings
1669 Prints file-backed mappings loaded from a core file's note section.
1670 Output is expected to be similar to that of "info proc mappings".
1672 set debug fortran-array-slicing on|off
1673 show debug fortran-array-slicing
1674 Print debugging when taking slices of Fortran arrays.
1676 set fortran repack-array-slices on|off
1677 show fortran repack-array-slices
1678 When taking slices from Fortran arrays and strings, if the slice is
1679 non-contiguous within the original value then, when this option is
1680 on, the new value will be repacked into a single contiguous value.
1681 When this option is off, then the value returned will consist of a
1682 descriptor that describes the slice within the memory of the
1683 original parent value.
1687 alias [-a] [--] ALIAS = COMMAND [DEFAULT-ARGS...]
1688 The alias command can now specify default args for an alias.
1689 GDB automatically prepends the alias default args to the argument list
1690 provided explicitly by the user.
1691 For example, to have a backtrace with full details, you can define
1692 an alias 'bt_ALL' as
1693 'alias bt_ALL = backtrace -entry-values both -frame-arg all
1694 -past-main -past-entry -full'.
1695 Alias default arguments can also use a set of nested 'with' commands,
1696 e.g. 'alias pp10 = with print pretty -- with print elem 10 -- print'
1697 defines the alias pp10 that will pretty print a maximum of 10 elements
1698 of the given expression (if the expression is an array).
1702 GNU/Linux/RISC-V (gdbserver) riscv*-*-linux*
1703 BPF bpf-unknown-none
1708 ** gdb.register_window_type can be used to implement new TUI windows
1711 ** Dynamic types can now be queried. gdb.Type has a new attribute,
1712 "dynamic", and gdb.Type.sizeof can be None for a dynamic type. A
1713 field of a dynamic type may have None for its "bitpos" attribute
1716 ** Commands written in Python can be in the "TUI" help class by
1717 registering with the new constant gdb.COMMAND_TUI.
1719 ** New method gdb.PendingFrame.architecture () to retrieve the
1720 architecture of the pending frame.
1722 ** New gdb.Architecture.registers method that returns a
1723 gdb.RegisterDescriptorIterator object, an iterator that returns
1724 gdb.RegisterDescriptor objects. The new RegisterDescriptor is a
1725 way to query the registers available for an architecture.
1727 ** New gdb.Architecture.register_groups method that returns a
1728 gdb.RegisterGroupIterator object, an iterator that returns
1729 gdb.RegisterGroup objects. The new RegisterGroup is a way to
1730 discover the available register groups.
1734 ** GDB can now be built with GNU Guile 3.0 and 2.2 in addition to 2.0.
1736 ** Procedures 'memory-port-read-buffer-size',
1737 'set-memory-port-read-buffer-size!', 'memory-port-write-buffer-size',
1738 and 'set-memory-port-write-buffer-size!' are deprecated. When
1739 using Guile 2.2 and later, users who need to control the size of
1740 a memory port's internal buffer can use the 'setvbuf' procedure.
1742 *** Changes in GDB 9
1744 * 'thread-exited' event is now available in the annotations interface.
1746 * New built-in convenience variables $_gdb_major and $_gdb_minor
1747 provide the GDB version. They are handy for conditionally using
1748 features available only in or since specific GDB versions, in
1749 scripts that should work error-free with many different versions,
1750 such as in system-wide init files.
1752 * New built-in convenience functions $_gdb_setting, $_gdb_setting_str,
1753 $_gdb_maint_setting and $_gdb_maint_setting_str provide access to values
1754 of the GDB settings and the GDB maintenance settings. They are handy
1755 for changing the logic of user defined commands depending on the
1756 current GDB settings.
1758 * GDB now supports Thread Local Storage (TLS) variables on several
1759 FreeBSD architectures (amd64, i386, powerpc, riscv). Other
1760 architectures require kernel changes. TLS is not yet supported for
1761 amd64 and i386 process core dumps.
1763 * Support for Pointer Authentication (PAC) on AArch64 Linux. Return
1764 addresses that required unmasking are shown in the backtrace with the
1767 * Two new convenience functions $_cimag and $_creal that extract the
1768 imaginary and real parts respectively from complex numbers.
1770 * New built-in convenience variables $_shell_exitcode and $_shell_exitsignal
1771 provide the exitcode or exit status of the shell commands launched by
1772 GDB commands such as "shell", "pipe" and "make".
1774 * The command define-prefix can now define user defined prefix commands.
1775 User defined commands can now be defined using these user defined prefix
1778 * Command names can now use the . character.
1780 * The RX port now supports XML target descriptions.
1782 * GDB now shows the Ada task names at more places, e.g. in task switching
1785 * GDB can now be compiled with Python 3 on Windows.
1787 * New convenience variable $_ada_exception holds the address of the
1788 Ada exception being thrown. This is set by Ada-related catchpoints.
1790 * GDB can now place breakpoints on nested functions and subroutines in
1791 Fortran code. The '::' operator can be used between parent and
1792 child scopes when placing breakpoints, for example:
1794 (gdb) break outer_function::inner_function
1796 The 'outer_function::' prefix is only needed if 'inner_function' is
1797 not visible in the current scope.
1799 * In addition to the system-wide gdbinit file, if configured with
1800 --with-system-gdbinit-dir, GDB will now also load files in that directory
1801 as system gdbinit files, unless the -nx or -n flag is provided. Files
1802 with extensions .gdb, .py and .scm are supported as long as GDB was
1803 compiled with support for that language.
1805 * GDB now supports multithreaded symbol loading for higher performance.
1806 This feature is still in testing, so it is disabled by default. You
1807 can turn it on using 'maint set worker-threads unlimited'.
1811 ** The gdb.Value type has a new method 'format_string' which returns a
1812 string representing the value. The formatting is controlled by the
1813 optional keyword arguments: 'raw', 'pretty_arrays', 'pretty_structs',
1814 'array_indexes', 'symbols', 'unions', 'deref_refs', 'actual_objects',
1815 'static_members', 'max_elements', 'repeat_threshold', and 'format'.
1817 ** gdb.Type has a new property 'objfile' which returns the objfile the
1818 type was defined in.
1820 ** The frame information printed by the python frame filtering code
1821 is now consistent with what the 'backtrace' command prints when
1822 there are no filters, or when the 'backtrace' '-no-filters' option
1825 ** The new function gdb.lookup_static_symbol can be used to look up
1826 symbols with static linkage.
1828 ** The new function gdb.lookup_static_symbols can be used to look up
1829 all static symbols with static linkage.
1831 ** gdb.Objfile has new methods 'lookup_global_symbol' and
1832 'lookup_static_symbol' to lookup a symbol from this objfile only.
1834 ** gdb.Block now supports the dictionary syntax for accessing symbols in
1835 this block (e.g. block['local_variable']).
1839 | [COMMAND] | SHELL_COMMAND
1840 | -d DELIM COMMAND DELIM SHELL_COMMAND
1841 pipe [COMMAND] | SHELL_COMMAND
1842 pipe -d DELIM COMMAND DELIM SHELL_COMMAND
1843 Executes COMMAND and sends its output to SHELL_COMMAND.
1844 With no COMMAND, repeat the last executed command
1845 and send its output to SHELL_COMMAND.
1847 define-prefix COMMAND
1848 Define or mark a command as a user-defined prefix command.
1850 with SETTING [VALUE] [-- COMMAND]
1851 w SETTING [VALUE] [-- COMMAND]
1852 Temporarily set SETTING, run COMMAND, and restore SETTING.
1853 Usage: with SETTING -- COMMAND
1854 With no COMMAND, repeats the last executed command.
1855 SETTING is any GDB setting you can change with the "set"
1856 subcommands. For example, 'with language c -- print someobj'
1857 temporarily switches to the C language in order to print someobj.
1858 Settings can be combined: 'w lang c -- w print elements unlimited --
1859 usercmd' switches to the C language and runs usercmd with no limit
1860 of array elements to print.
1862 maint with SETTING [VALUE] [-- COMMAND]
1863 Like "with", but works with "maintenance set" settings.
1865 set may-call-functions [on|off]
1866 show may-call-functions
1867 This controls whether GDB will attempt to call functions in
1868 the program, such as with expressions in the print command. It
1869 defaults to on. Calling functions in the program being debugged
1870 can have undesired side effects. It is now possible to forbid
1871 such function calls. If function calls are forbidden, GDB will throw
1872 an error when a command (such as print expression) calls a function
1875 set print finish [on|off]
1877 This controls whether the `finish' command will display the value
1878 that is returned by the current function. When `off', the value is
1879 still entered into the value history, but it is not printed. The
1883 show print max-depth
1884 Allows deeply nested structures to be simplified when printing by
1885 replacing deeply nested parts (beyond the max-depth) with ellipses.
1886 The default max-depth is 20, but this can be set to unlimited to get
1887 the old behavior back.
1889 set print raw-values [on|off]
1890 show print raw-values
1891 By default, GDB applies the enabled pretty printers when printing a
1892 value. This allows to ignore the enabled pretty printers for a series
1893 of commands. The default is 'off'.
1895 set logging debugredirect [on|off]
1896 By default, GDB debug output will go to both the terminal and the logfile.
1897 Set if you want debug output to go only to the log file.
1899 set style title foreground COLOR
1900 set style title background COLOR
1901 set style title intensity VALUE
1902 Control the styling of titles.
1904 set style highlight foreground COLOR
1905 set style highlight background COLOR
1906 set style highlight intensity VALUE
1907 Control the styling of highlightings.
1909 maint set worker-threads
1910 maint show worker-threads
1911 Control the number of worker threads that can be used by GDB. The
1912 default is 0. "unlimited" lets GDB choose a number that is
1913 reasonable. Currently worker threads are only used when demangling
1914 the names of linker symbols.
1916 set style tui-border foreground COLOR
1917 set style tui-border background COLOR
1918 Control the styling of TUI borders.
1920 set style tui-active-border foreground COLOR
1921 set style tui-active-border background COLOR
1922 Control the styling of the active TUI border.
1924 maint set test-settings KIND
1925 maint show test-settings KIND
1926 A set of commands used by the testsuite for exercising the settings
1929 maint set tui-resize-message [on|off]
1930 maint show tui-resize-message
1931 Control whether GDB prints a message each time the terminal is
1932 resized when in TUI mode. This is primarily useful for testing the
1935 set print frame-info [short-location|location|location-and-address
1936 |source-and-location|source-line|auto]
1937 show print frame-info
1938 This controls what frame information is printed by the commands printing
1939 a frame. This setting will e.g. influence the behaviour of 'backtrace',
1940 'frame', 'stepi'. The python frame filtering also respect this setting.
1941 The 'backtrace' '-frame-info' option can override this global setting.
1943 set tui compact-source
1944 show tui compact-source
1946 Enable the "compact" display mode for the TUI source window. The
1947 compact display uses only as much space as is needed for the line
1948 numbers in the current file, and only a single space to separate the
1949 line numbers from the source.
1951 info modules [-q] [REGEXP]
1952 Return a list of Fortran modules matching REGEXP, or all modules if
1955 info module functions [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
1956 Return a list of functions within all modules, grouped by module.
1957 The list of functions can be restricted with the optional regular
1958 expressions. MODULE_REGEXP matches against the module name,
1959 TYPE_REGEXP matches against the function type signature, and REGEXP
1960 matches against the function name.
1962 info module variables [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
1963 Return a list of variables within all modules, grouped by module.
1964 The list of variables can be restricted with the optional regular
1965 expressions. MODULE_REGEXP matches against the module name,
1966 TYPE_REGEXP matches against the variable type, and REGEXP matches
1967 against the variable name.
1969 set debug remote-packet-max-chars
1970 show debug remote-packet-max-chars
1971 Controls the number of characters to output in a remote packet when using
1973 The default is 512 bytes.
1976 Lists the target connections currently in use.
1981 The "help" command uses the title style to enhance the
1982 readibility of its output by styling the classes and
1986 Similarly to "help", the "apropos" command also uses the
1987 title style for the command names. "apropos" accepts now
1988 a flag "-v" (verbose) to show the full documentation
1989 of matching commands and to use the highlight style to mark
1990 the documentation parts matching REGEXP.
1994 The GDB printf and eval commands can now print C-style and Ada-style
1995 string convenience variables without calling functions in the program.
1996 This allows to do formatted printing of strings without having
1997 a running inferior, or when debugging a core dump.
1999 info sources [-dirname | -basename] [--] [REGEXP]
2000 This command has now optional arguments to only print the files
2001 whose names match REGEXP. The arguments -dirname and -basename
2002 allow to restrict matching respectively to the dirname and basename
2006 The "show style" and its subcommands are now styling
2007 a style name in their output using its own style, to help
2008 the user visualize the different styles.
2010 set print frame-arguments
2011 The new value 'presence' indicates to only indicate the presence of
2012 arguments using ..., instead of printing argument names and values.
2014 set print raw-frame-arguments
2015 show print raw-frame-arguments
2017 These commands replace the similarly-named "set/show print raw
2018 frame-arguments" commands (now with a dash instead of a space). The
2019 old commands are now deprecated and may be removed in a future
2022 add-inferior [-no-connection]
2023 The add-inferior command now supports a "-no-connection" flag that
2024 makes the new inferior start with no target connection associated.
2025 By default, the new inferior inherits the target connection of the
2026 current inferior. See also "info connections".
2029 This command's output now includes a new "Connection" column
2030 indicating which target connection an inferior is bound to. See
2031 "info connections" above.
2033 maint test-options require-delimiter
2034 maint test-options unknown-is-error
2035 maint test-options unknown-is-operand
2036 maint show test-options-completion-result
2037 Commands used by the testsuite to validate the command options
2040 focus, winheight, +, -, >, <
2041 These commands are now case-sensitive.
2043 * New command options, command completion
2045 GDB now has a standard infrastructure to support dash-style command
2046 options ('-OPT'). One benefit is that commands that use it can
2047 easily support completion of command line arguments. Try "CMD
2048 -[TAB]" or "help CMD" to find options supported by a command. Over
2049 time, we intend to migrate most commands to this infrastructure. A
2050 number of commands got support for new command options in this
2053 ** The "print" and "compile print" commands now support a number of
2054 options that allow overriding relevant global print settings as
2055 set by "set print" subcommands:
2059 -array-indexes [on|off]
2060 -elements NUMBER|unlimited
2064 -raw-values [on|off]
2065 -repeats NUMBER|unlimited
2066 -static-members [on|off]
2071 Note that because the "print"/"compile print" commands accept
2072 arbitrary expressions which may look like options (including
2073 abbreviations), if you specify any command option, then you must
2074 use a double dash ("--") to mark the end of argument processing.
2076 ** The "backtrace" command now supports a number of options that
2077 allow overriding relevant global print settings as set by "set
2078 backtrace" and "set print" subcommands:
2080 -entry-values no|only|preferred|if-needed|both|compact|default
2081 -frame-arguments all|scalars|none
2082 -raw-frame-arguments [on|off]
2083 -frame-info auto|source-line|location|source-and-location
2084 |location-and-address|short-location
2086 -past-entry [on|off]
2088 In addition, the full/no-filters/hide qualifiers are now also
2089 exposed as command options too:
2095 ** The "frame apply", "tfaas" and "faas" commands similarly now
2096 support the following options:
2099 -past-entry [on|off]
2101 ** The new "info sources" options -dirname and -basename options
2102 are using the standard '-OPT' infrastructure.
2104 All options above can also be abbreviated. The argument of boolean
2105 (on/off) options can be 0/1 too, and also the argument is assumed
2106 "on" if omitted. This allows writing compact command invocations,
2109 (gdb) p -ra -p -o 0 -- *myptr
2111 The above is equivalent to:
2113 (gdb) print -raw-values -pretty -object off -- *myptr
2115 ** The "info types" command now supports the '-q' flag to disable
2116 printing of some header information in a similar fashion to "info
2117 variables" and "info functions".
2119 ** The "info variables", "info functions", and "whereis" commands
2120 now take a '-n' flag that excludes non-debug symbols (symbols
2121 from the symbol table, not from the debug info such as DWARF)
2124 * Completion improvements
2126 ** GDB can now complete the options of the "thread apply all" and
2127 "taas" commands, and their "-ascending" option can now be
2130 ** GDB can now complete the options of the "info threads", "info
2131 functions", "info variables", "info locals", and "info args"
2134 ** GDB can now complete the options of the "compile file" and
2135 "compile code" commands. The "compile file" command now
2136 completes on filenames.
2138 ** GDB can now complete the backtrace command's
2139 "full/no-filters/hide" qualifiers.
2141 * In settings, you can now abbreviate "unlimited".
2143 E.g., "set print elements u" is now equivalent to "set print
2144 elements unlimited".
2149 This lists all the possible completions for the rest of the line, if it
2150 were to be given as a command itself. This is intended for use by MI
2151 frontends in cases when separate CLI and MI channels cannot be used.
2153 -catch-throw, -catch-rethrow, and -catch-catch
2154 These can be used to catch C++ exceptions in a similar fashion to
2155 the CLI commands 'catch throw', 'catch rethrow', and 'catch catch'.
2157 -symbol-info-functions, -symbol-info-types, and -symbol-info-variables
2158 These commands are the MI equivalent of the CLI commands 'info
2159 functions', 'info types', and 'info variables' respectively.
2161 -symbol-info-modules, this is the MI equivalent of the CLI 'info
2164 -symbol-info-module-functions and -symbol-info-module-variables.
2165 These commands are the MI equivalent of the CLI commands 'info
2166 module functions' and 'info module variables'.
2170 ** The default version of the MI interpreter is now 3 (-i=mi3).
2172 ** The output of information about multi-location breakpoints (which is
2173 syntactically incorrect in MI 2) has changed in MI 3. This affects
2174 the following commands and events:
2178 - =breakpoint-created
2179 - =breakpoint-modified
2181 The -fix-multi-location-breakpoint-output command can be used to enable
2182 this behavior with previous MI versions.
2184 ** Backtraces and frames include a new optional field addr_flags which is
2185 given after the addr field. On AArch64 this contains PAC if the address
2186 has been masked in the frame. On all other targets the field is not
2191 The testsuite now creates the files gdb.cmd (containing the arguments
2192 used to launch GDB) and gdb.in (containing all the commands sent to
2193 GDB) in the output directory for each test script. Multiple invocations
2194 are appended with .1, .2, .3 etc.
2196 * Building GDB and GDBserver now requires GNU make >= 3.82.
2198 Using another implementation of the make program or an earlier version of
2199 GNU make to build GDB or GDBserver is not supported.
2201 * Building GDB now requires GNU readline >= 7.0.
2203 GDB now bundles GNU readline 8.0, but if you choose to use
2204 --with-system-readline, only readline >= 7.0 can be used.
2206 * The TUI SingleKey keymap is now named "SingleKey". This can be used
2207 from .inputrc to bind keys in this keymap. This feature is only
2208 available when gdb is built against GNU readline 8.0 or later.
2210 * Removed targets and native configurations
2212 GDB no longer supports debugging the Cell Broadband Engine. This includes
2213 both debugging standalone Cell/B.E. SPU applications and integrated debugging
2214 of Cell/B.E. applications that use both the PPU and SPU architectures.
2220 * Removed targets and native configurations
2222 Solaris 10 i?86-*-solaris2.10, x86_64-*-solaris2.10,
2223 sparc*-*-solaris2.10
2225 *** Changes in GDB 8.3
2227 * GDB and GDBserver now support access to additional registers on
2228 PowerPC GNU/Linux targets: PPR, DSCR, TAR, EBB/PMU registers, and
2231 * GDB now has experimental support for the compilation and injection of
2232 C++ source code into the inferior. This beta release does not include
2233 support for several language features, such as templates, constructors,
2236 This feature requires GCC 7.1 or higher built with libcp1.so
2239 * GDB and GDBserver now support IPv6 connections. IPv6 addresses
2240 can be passed using the '[ADDRESS]:PORT' notation, or the regular
2241 'ADDRESS:PORT' method.
2243 * DWARF index cache: GDB can now automatically save indices of DWARF
2244 symbols on disk to speed up further loading of the same binaries.
2246 * Ada task switching is now supported on aarch64-elf targets when
2247 debugging a program using the Ravenscar Profile. For more information,
2248 see the "Tasking Support when using the Ravenscar Profile" section
2249 in the GDB user manual.
2251 * GDB in batch mode now exits with status 1 if the last command to be
2254 * The RISC-V target now supports target descriptions.
2256 * System call catchpoints now support system call aliases on FreeBSD.
2257 When the ABI of a system call changes in FreeBSD, this is
2258 implemented by leaving a compatibility system call using the old ABI
2259 at the existing number and allocating a new system call number for
2260 the new ABI. For example, FreeBSD 12 altered the layout of 'struct
2261 kevent' used by the 'kevent' system call. As a result, FreeBSD 12
2262 kernels ship with both 'kevent' and 'freebsd11_kevent' system calls.
2263 The 'freebsd11_kevent' system call is assigned an alias of 'kevent'
2264 so that a system call catchpoint for the 'kevent' system call will
2265 catch invocations of both the 'kevent' and 'freebsd11_kevent'
2266 binaries. This ensures that 'kevent' system calls are caught for
2267 binaries using either the old or new ABIs.
2269 * Terminal styling is now available for the CLI and the TUI. GNU
2270 Source Highlight can additionally be used to provide styling of
2271 source code snippets. See the "set style" commands, below, for more
2274 * Removed support for old demangling styles arm, edg, gnu, hp and
2279 set debug compile-cplus-types
2280 show debug compile-cplus-types
2281 Control the display of debug output about type conversion in the
2282 C++ compile feature. Commands have no effect while compiling
2283 for other languages.
2287 Control whether debug output about files/functions skipping is
2290 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
2291 Apply a command to some frames.
2292 FLAG arguments allow to control what output to produce and how to handle
2293 errors raised when applying COMMAND to a frame.
2296 Apply a command to all threads (ignoring errors and empty output).
2297 Shortcut for 'thread apply all -s COMMAND'.
2300 Apply a command to all frames (ignoring errors and empty output).
2301 Shortcut for 'frame apply all -s COMMAND'.
2304 Apply a command to all frames of all threads (ignoring errors and empty
2306 Shortcut for 'thread apply all -s frame apply all -s COMMAND'.
2308 maint set dwarf unwinders (on|off)
2309 maint show dwarf unwinders
2310 Control whether DWARF unwinders can be used.
2313 Display a list of open files for a process.
2317 Changes to the "frame", "select-frame", and "info frame" CLI commands.
2318 These commands all now take a frame specification which
2319 is either a frame level, or one of the keywords 'level', 'address',
2320 'function', or 'view' followed by a parameter. Selecting a frame by
2321 address, or viewing a frame outside the current backtrace now
2322 requires the use of a keyword. Selecting a frame by level is
2323 unchanged. The MI comment "-stack-select-frame" is unchanged.
2325 target remote FILENAME
2326 target extended-remote FILENAME
2327 If FILENAME is a Unix domain socket, GDB will attempt to connect
2328 to this socket instead of opening FILENAME as a character device.
2330 info args [-q] [-t TYPEREGEXP] [NAMEREGEXP]
2331 info functions [-q] [-t TYPEREGEXP] [NAMEREGEXP]
2332 info locals [-q] [-t TYPEREGEXP] [NAMEREGEXP]
2333 info variables [-q] [-t TYPEREGEXP] [NAMEREGEXP]
2334 These commands can now print only the searched entities
2335 matching the provided regexp(s), giving a condition
2336 on the entity names or entity types. The flag -q disables
2337 printing headers or informations messages.
2343 These commands now determine the syntax for the shown entities
2344 according to the language chosen by `set language'. In particular,
2345 `set language auto' means to automatically choose the language of
2348 thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
2349 The 'thread apply' command accepts new FLAG arguments.
2350 FLAG arguments allow to control what output to produce and how to handle
2351 errors raised when applying COMMAND to a thread.
2353 set tui tab-width NCHARS
2354 show tui tab-width NCHARS
2355 "set tui tab-width" replaces the "tabset" command, which has been deprecated.
2357 set style enabled [on|off]
2359 Enable or disable terminal styling. Styling is enabled by default
2360 on most hosts, but disabled by default when in batch mode.
2362 set style sources [on|off]
2364 Enable or disable source code styling. Source code styling is
2365 enabled by default, but only takes effect if styling in general is
2366 enabled, and if GDB was linked with GNU Source Highlight.
2368 set style filename foreground COLOR
2369 set style filename background COLOR
2370 set style filename intensity VALUE
2371 Control the styling of file names.
2373 set style function foreground COLOR
2374 set style function background COLOR
2375 set style function intensity VALUE
2376 Control the styling of function names.
2378 set style variable foreground COLOR
2379 set style variable background COLOR
2380 set style variable intensity VALUE
2381 Control the styling of variable names.
2383 set style address foreground COLOR
2384 set style address background COLOR
2385 set style address intensity VALUE
2386 Control the styling of addresses.
2390 ** The '-data-disassemble' MI command now accepts an '-a' option to
2391 disassemble the whole function surrounding the given program
2392 counter value or function name. Support for this feature can be
2393 verified by using the "-list-features" command, which should
2394 contain "data-disassemble-a-option".
2396 ** Command responses and notifications that include a frame now include
2397 the frame's architecture in a new "arch" attribute.
2399 * New native configurations
2401 GNU/Linux/RISC-V riscv*-*-linux*
2402 FreeBSD/riscv riscv*-*-freebsd*
2406 GNU/Linux/RISC-V riscv*-*-linux*
2407 CSKY ELF csky*-*-elf
2408 CSKY GNU/LINUX csky*-*-linux
2409 FreeBSD/riscv riscv*-*-freebsd*
2411 GNU/Linux/OpenRISC or1k*-*-linux*
2415 GDB no longer supports native debugging on versions of MS-Windows
2420 ** GDB no longer supports Python versions less than 2.6.
2422 ** The gdb.Inferior type has a new 'progspace' property, which is the program
2423 space associated to that inferior.
2425 ** The gdb.Progspace type has a new 'objfiles' method, which returns the list
2426 of objfiles associated to that program space.
2428 ** gdb.SYMBOL_LOC_COMMON_BLOCK, gdb.SYMBOL_MODULE_DOMAIN, and
2429 gdb.SYMBOL_COMMON_BLOCK_DOMAIN were added to reflect changes to
2432 ** gdb.SYMBOL_VARIABLES_DOMAIN, gdb.SYMBOL_FUNCTIONS_DOMAIN, and
2433 gdb.SYMBOL_TYPES_DOMAIN are now deprecated. These were never
2434 correct and did not work properly.
2436 ** The gdb.Value type has a new constructor, which is used to construct a
2437 gdb.Value from a Python buffer object and a gdb.Type.
2443 Enable or disable the undefined behavior sanitizer. This is
2444 disabled by default, but passing --enable-ubsan=yes or
2445 --enable-ubsan=auto to configure will enable it. Enabling this can
2446 cause a performance penalty. The undefined behavior sanitizer was
2447 first introduced in GCC 4.9.
2449 *** Changes in GDB 8.2
2451 * The 'set disassembler-options' command now supports specifying options
2452 for the MIPS target.
2454 * The 'symbol-file' command now accepts an '-o' option to add a relative
2455 offset to all sections.
2457 * Similarly, the 'add-symbol-file' command also accepts an '-o' option to add
2458 a relative offset to all sections, but it allows to override the load
2459 address of individual sections using '-s'.
2461 * The 'add-symbol-file' command no longer requires the second argument
2462 (address of the text section).
2464 * The endianness used with the 'set endian auto' mode in the absence of
2465 an executable selected for debugging is now the last endianness chosen
2466 either by one of the 'set endian big' and 'set endian little' commands
2467 or by inferring from the last executable used, rather than the startup
2470 * The pager now allows a "c" response, meaning to disable the pager
2471 for the rest of the current command.
2473 * The commands 'info variables/functions/types' now show the source line
2474 numbers of symbol definitions when available.
2476 * 'info proc' now works on running processes on FreeBSD systems and core
2477 files created on FreeBSD systems.
2479 * C expressions can now use _Alignof, and C++ expressions can now use
2482 * Support for SVE on AArch64 Linux. Note that GDB does not detect changes to
2483 the vector length while the process is running.
2489 Control display of debugging info regarding the FreeBSD native target.
2491 set|show varsize-limit
2492 This new setting allows the user to control the maximum size of Ada
2493 objects being printed when those objects have a variable type,
2494 instead of that maximum size being hardcoded to 65536 bytes.
2496 set|show record btrace cpu
2497 Controls the processor to be used for enabling errata workarounds for
2498 branch trace decode.
2500 maint check libthread-db
2501 Run integrity checks on the current inferior's thread debugging
2504 maint set check-libthread-db (on|off)
2505 maint show check-libthread-db
2506 Control whether to run integrity checks on inferior specific thread
2507 debugging libraries as they are loaded. The default is not to
2508 perform such checks.
2512 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
2514 ** The commands attached to a breakpoint can be set by assigning to
2515 the breakpoint's "commands" field.
2517 ** gdb.execute can now execute multi-line gdb commands.
2519 ** The new functions gdb.convenience_variable and
2520 gdb.set_convenience_variable can be used to get and set the value
2521 of convenience variables.
2523 ** A gdb.Parameter will no longer print the "set" help text on an
2524 ordinary "set"; instead by default a "set" will be silent unless
2525 the get_set_string method returns a non-empty string.
2529 RiscV ELF riscv*-*-elf
2531 * Removed targets and native configurations
2533 m88k running OpenBSD m88*-*-openbsd*
2534 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
2535 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
2536 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
2538 * Aarch64/Linux hardware watchpoints improvements
2540 Hardware watchpoints on unaligned addresses are now properly
2541 supported when running Linux kernel 4.10 or higher: read and access
2542 watchpoints are no longer spuriously missed, and all watchpoints
2543 lengths between 1 and 8 bytes are supported. On older kernels,
2544 watchpoints set on unaligned addresses are no longer missed, with
2545 the tradeoff that there is a possibility of false hits being
2550 --enable-codesign=CERT
2551 This can be used to invoke "codesign -s CERT" after building gdb.
2552 This option is useful on macOS, where code signing is required for
2553 gdb to work properly.
2555 --disable-gdbcli has been removed
2556 This is now silently accepted, but does nothing.
2558 *** Changes in GDB 8.1
2560 * GDB now supports dynamically creating arbitrary register groups specified
2561 in XML target descriptions. This allows for finer grain grouping of
2562 registers on systems with a large amount of registers.
2564 * The 'ptype' command now accepts a '/o' flag, which prints the
2565 offsets and sizes of fields in a struct, like the pahole(1) tool.
2567 * New "--readnever" command line option instructs GDB to not read each
2568 symbol file's symbolic debug information. This makes startup faster
2569 but at the expense of not being able to perform symbolic debugging.
2570 This option is intended for use cases where symbolic debugging will
2571 not be used, e.g., when you only need to dump the debuggee's core.
2573 * GDB now uses the GNU MPFR library, if available, to emulate target
2574 floating-point arithmetic during expression evaluation when the target
2575 uses different floating-point formats than the host. At least version
2576 3.1 of GNU MPFR is required.
2578 * GDB now supports access to the guarded-storage-control registers and the
2579 software-based guarded-storage broadcast control registers on IBM z14.
2581 * On Unix systems, GDB now supports transmitting environment variables
2582 that are to be set or unset to GDBserver. These variables will
2583 affect the environment to be passed to the remote inferior.
2585 To inform GDB of environment variables that are to be transmitted to
2586 GDBserver, use the "set environment" command. Only user set
2587 environment variables are sent to GDBserver.
2589 To inform GDB of environment variables that are to be unset before
2590 the remote inferior is started by the GDBserver, use the "unset
2591 environment" command.
2593 * Completion improvements
2595 ** GDB can now complete function parameters in linespecs and
2596 explicit locations without quoting. When setting breakpoints,
2597 quoting around functions names to help with TAB-completion is
2598 generally no longer necessary. For example, this now completes
2601 (gdb) b function(in[TAB]
2602 (gdb) b function(int)
2604 Related, GDB is no longer confused with completing functions in
2605 C++ anonymous namespaces:
2608 (gdb) b (anonymous namespace)::[TAB][TAB]
2609 (anonymous namespace)::a_function()
2610 (anonymous namespace)::b_function()
2612 ** GDB now has much improved linespec and explicit locations TAB
2613 completion support, that better understands what you're
2614 completing and offers better suggestions. For example, GDB no
2615 longer offers data symbols as possible completions when you're
2616 setting a breakpoint.
2618 ** GDB now TAB-completes label symbol names.
2620 ** The "complete" command now mimics TAB completion accurately.
2622 * New command line options (gcore)
2625 Dump all memory mappings.
2627 * Breakpoints on C++ functions are now set on all scopes by default
2629 By default, breakpoints on functions/methods are now interpreted as
2630 specifying all functions with the given name ignoring missing
2631 leading scopes (namespaces and classes).
2633 For example, assuming a C++ program with symbols named:
2638 both commands "break func()" and "break B::func()" set a breakpoint
2641 You can use the new flag "-qualified" to override this. This makes
2642 GDB interpret the specified function name as a complete
2643 fully-qualified name instead. For example, using the same C++
2644 program, the "break -q B::func" command sets a breakpoint on
2645 "B::func", only. A parameter has been added to the Python
2646 gdb.Breakpoint constructor to achieve the same result when creating
2647 a breakpoint from Python.
2649 * Breakpoints on functions marked with C++ ABI tags
2651 GDB can now set breakpoints on functions marked with C++ ABI tags
2652 (e.g., [abi:cxx11]). See here for a description of ABI tags:
2653 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
2655 Functions with a C++11 abi tag are demangled/displayed like this:
2657 function[abi:cxx11](int)
2660 You can now set a breakpoint on such functions simply as if they had
2663 (gdb) b function(int)
2665 Or if you need to disambiguate between tags, like:
2667 (gdb) b function[abi:other_tag](int)
2669 Tab completion was adjusted accordingly as well.
2673 ** New events gdb.new_inferior, gdb.inferior_deleted, and
2674 gdb.new_thread are emitted. See the manual for further
2675 description of these.
2677 ** A new function, "gdb.rbreak" has been added to the Python API.
2678 This function allows the setting of a large number of breakpoints
2679 via a regex pattern in Python. See the manual for further details.
2681 ** Python breakpoints can now accept explicit locations. See the
2682 manual for a further description of this feature.
2685 * New features in the GDB remote stub, GDBserver
2687 ** GDBserver is now able to start inferior processes with a
2688 specified initial working directory.
2690 The user can set the desired working directory to be used from
2691 GDB using the new "set cwd" command.
2693 ** New "--selftest" command line option runs some GDBserver self
2694 tests. These self tests are disabled in releases.
2696 ** On Unix systems, GDBserver now does globbing expansion and variable
2697 substitution in inferior command line arguments.
2699 This is done by starting inferiors using a shell, like GDB does.
2700 See "set startup-with-shell" in the user manual for how to disable
2701 this from GDB when using "target extended-remote". When using
2702 "target remote", you can disable the startup with shell by using the
2703 new "--no-startup-with-shell" GDBserver command line option.
2705 ** On Unix systems, GDBserver now supports receiving environment
2706 variables that are to be set or unset from GDB. These variables
2707 will affect the environment to be passed to the inferior.
2709 * When catching an Ada exception raised with a message, GDB now prints
2710 the message in the catchpoint hit notification. In GDB/MI mode, that
2711 information is provided as an extra field named "exception-message"
2712 in the *stopped notification.
2714 * Trait objects can now be inspected When debugging Rust code. This
2715 requires compiler support which will appear in Rust 1.24.
2717 * New remote packets
2719 QEnvironmentHexEncoded
2720 Inform GDBserver of an environment variable that is to be passed to
2721 the inferior when starting it.
2724 Inform GDBserver of an environment variable that is to be unset
2725 before starting the remote inferior.
2728 Inform GDBserver that the environment should be reset (i.e.,
2729 user-set environment variables should be unset).
2732 Indicates whether the inferior must be started with a shell or not.
2735 Tell GDBserver that the inferior to be started should use a specific
2738 * The "maintenance print c-tdesc" command now takes an optional
2739 argument which is the file name of XML target description.
2741 * The "maintenance selftest" command now takes an optional argument to
2742 filter the tests to be run.
2744 * The "enable", and "disable" commands now accept a range of
2745 breakpoint locations, e.g. "enable 1.3-5".
2750 Set and show the current working directory for the inferior.
2752 set|show compile-gcc
2753 Set and show compilation command used for compiling and injecting code
2754 with the 'compile' commands.
2756 set debug separate-debug-file
2757 show debug separate-debug-file
2758 Control the display of debug output about separate debug file search.
2760 set dump-excluded-mappings
2761 show dump-excluded-mappings
2762 Control whether mappings marked with the VM_DONTDUMP flag should be
2763 dumped when generating a core file.
2765 maint info selftests
2766 List the registered selftests.
2769 Start the debugged program stopping at the first instruction.
2772 Control display of debugging messages related to OpenRISC targets.
2774 set|show print type nested-type-limit
2775 Set and show the limit of nesting level for nested types that the
2776 type printer will show.
2778 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
2781 * Safer/improved support for debugging with no debug info
2783 GDB no longer assumes functions with no debug information return
2786 This means that GDB now refuses to call such functions unless you
2787 tell it the function's type, by either casting the call to the
2788 declared return type, or by casting the function to a function
2789 pointer of the right type, and calling that:
2791 (gdb) p getenv ("PATH")
2792 'getenv' has unknown return type; cast the call to its declared return type
2793 (gdb) p (char *) getenv ("PATH")
2794 $1 = 0x7fffffffe "/usr/local/bin:/"...
2795 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
2796 $2 = 0x7fffffffe "/usr/local/bin:/"...
2798 Similarly, GDB no longer assumes that global variables with no debug
2799 info have type 'int', and refuses to print the variable's value
2800 unless you tell it the variable's type:
2803 'var' has unknown type; cast it to its declared type
2807 * New native configurations
2809 FreeBSD/aarch64 aarch64*-*-freebsd*
2810 FreeBSD/arm arm*-*-freebsd*
2814 FreeBSD/aarch64 aarch64*-*-freebsd*
2815 FreeBSD/arm arm*-*-freebsd*
2816 OpenRISC ELF or1k*-*-elf
2818 * Removed targets and native configurations
2820 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
2822 *** Changes in GDB 8.0
2824 * GDB now supports access to the PKU register on GNU/Linux. The register is
2825 added by the Memory Protection Keys for Userspace feature which will be
2826 available in future Intel CPUs.
2828 * GDB now supports C++11 rvalue references.
2832 ** New functions to start, stop and access a running btrace recording.
2833 ** Rvalue references are now supported in gdb.Type.
2835 * GDB now supports recording and replaying rdrand and rdseed Intel 64
2838 * Building GDB and GDBserver now requires a C++11 compiler.
2840 For example, GCC 4.8 or later.
2842 It is no longer possible to build GDB or GDBserver with a C
2843 compiler. The --disable-build-with-cxx configure option has been
2846 * Building GDB and GDBserver now requires GNU make >= 3.81.
2848 It is no longer supported to build GDB or GDBserver with another
2849 implementation of the make program or an earlier version of GNU make.
2851 * Native debugging on MS-Windows supports command-line redirection
2853 Command-line arguments used for starting programs on MS-Windows can
2854 now include redirection symbols supported by native Windows shells,
2855 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
2856 as "run", "start", and "set args", as well as the corresponding MI
2859 * Support for thread names on MS-Windows.
2861 GDB now catches and handles the special exception that programs
2862 running on MS-Windows use to assign names to threads in the
2865 * Support for Java programs compiled with gcj has been removed.
2867 * User commands now accept an unlimited number of arguments.
2868 Previously, only up to 10 was accepted.
2870 * The "eval" command now expands user-defined command arguments.
2872 This makes it easier to process a variable number of arguments:
2877 eval "print $arg%d", $i
2882 * Target descriptions can now describe registers for sparc32 and sparc64.
2884 * GDB now supports DWARF version 5 (debug information format).
2885 Its .debug_names index is not yet supported.
2887 * New native configurations
2889 FreeBSD/mips mips*-*-freebsd
2893 Synopsys ARC arc*-*-elf32
2894 FreeBSD/mips mips*-*-freebsd
2896 * Removed targets and native configurations
2898 Alpha running FreeBSD alpha*-*-freebsd*
2899 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
2904 Erases all the flash memory regions reported by the target.
2906 maint print arc arc-instruction address
2907 Print internal disassembler information about instruction at a given address.
2911 set disassembler-options
2912 show disassembler-options
2913 Controls the passing of target specific information to the disassembler.
2914 If it is necessary to specify more than one disassembler option then
2915 multiple options can be placed together into a comma separated list.
2916 The default value is the empty string. Currently, the only supported
2917 targets are ARM, PowerPC and S/390.
2922 Erases all the flash memory regions reported by the target. This is
2923 equivalent to the CLI command flash-erase.
2925 -file-list-shared-libraries
2926 List the shared libraries in the program. This is
2927 equivalent to the CLI command "info shared".
2930 Catchpoints stopping the program when Ada exceptions are
2931 handled. This is equivalent to the CLI command "catch handlers".
2933 *** Changes in GDB 7.12
2935 * GDB and GDBserver now build with a C++ compiler by default.
2937 The --enable-build-with-cxx configure option is now enabled by
2938 default. One must now explicitly configure with
2939 --disable-build-with-cxx in order to build with a C compiler. This
2940 option will be removed in a future release.
2942 * GDBserver now supports recording btrace without maintaining an active
2945 * GDB now supports a negative repeat count in the 'x' command to examine
2946 memory backward from the given address. For example:
2949 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
2950 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
2951 (gdb) x/-5i 0x0000000000400580
2952 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
2953 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
2954 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
2955 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
2956 0x40057b <main(int, char**)+25>:
2957 callq 0x400536 <Func1(int, char const*)>
2959 * Fortran: Support structures with fields of dynamic types and
2960 arrays of dynamic types.
2962 * The symbol dumping maintenance commands have new syntax.
2963 maint print symbols [-pc address] [--] [filename]
2964 maint print symbols [-objfile objfile] [-source source] [--] [filename]
2965 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
2966 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
2967 maint print msymbols [-objfile objfile] [--] [filename]
2969 * GDB now supports multibit bitfields and enums in target register
2972 * New Python-based convenience function $_as_string(val), which returns
2973 the textual representation of a value. This function is especially
2974 useful to obtain the text label of an enum value.
2976 * Intel MPX bound violation handling.
2978 Segmentation faults caused by a Intel MPX boundary violation
2979 now display the kind of violation (upper or lower), the memory
2980 address accessed and the memory bounds, along with the usual
2981 signal received and code location.
2985 Program received signal SIGSEGV, Segmentation fault
2986 Upper bound violation while accessing address 0x7fffffffc3b3
2987 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
2988 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
2990 * Rust language support.
2991 GDB now supports debugging programs written in the Rust programming
2992 language. See https://www.rust-lang.org/ for more information about
2995 * Support for running interpreters on specified input/output devices
2997 GDB now supports a new mechanism that allows frontends to provide
2998 fully featured GDB console views, as a better alternative to
2999 building such views on top of the "-interpreter-exec console"
3000 command. See the new "new-ui" command below. With that command,
3001 frontends can now start GDB in the traditional command-line mode
3002 running in an embedded terminal emulator widget, and create a
3003 separate MI interpreter running on a specified i/o device. In this
3004 way, GDB handles line editing, history, tab completion, etc. in the
3005 console all by itself, and the GUI uses the separate MI interpreter
3006 for its own control and synchronization, invisible to the command
3009 * The "catch syscall" command catches groups of related syscalls.
3011 The "catch syscall" command now supports catching a group of related
3012 syscalls using the 'group:' or 'g:' prefix.
3017 skip -gfile file-glob-pattern
3018 skip -function function
3019 skip -rfunction regular-expression
3020 A generalized form of the skip command, with new support for
3021 glob-style file names and regular expressions for function names.
3022 Additionally, a file spec and a function spec may now be combined.
3024 maint info line-table REGEXP
3025 Display the contents of GDB's internal line table data structure.
3028 Run any GDB unit tests that were compiled in.
3031 Start a new user interface instance running INTERP as interpreter,
3032 using the TTY file for input/output.
3036 ** gdb.Breakpoint objects have a new attribute "pending", which
3037 indicates whether the breakpoint is pending.
3038 ** Three new breakpoint-related events have been added:
3039 gdb.breakpoint_created, gdb.breakpoint_modified, and
3040 gdb.breakpoint_deleted.
3042 signal-event EVENTID
3043 Signal ("set") the given MS-Windows event object. This is used in
3044 conjunction with the Windows JIT debugging (AeDebug) support, where
3045 the OS suspends a crashing process until a debugger can attach to
3046 it. Resuming the crashing process, in order to debug it, is done by
3047 signalling an event.
3049 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
3050 was added in GDBserver, including JIT compiling fast tracepoint's
3051 conditional expression bytecode into native code.
3053 * Support for various remote target protocols and ROM monitors has
3056 target m32rsdi Remote M32R debugging over SDI
3057 target mips MIPS remote debugging protocol
3058 target pmon PMON ROM monitor
3059 target ddb NEC's DDB variant of PMON for Vr4300
3060 target rockhopper NEC RockHopper variant of PMON
3061 target lsi LSI variant of PMO
3063 * Support for tracepoints and fast tracepoints on powerpc-linux,
3064 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
3065 including JIT compiling fast tracepoint's conditional expression
3066 bytecode into native code.
3068 * MI async record =record-started now includes the method and format used for
3069 recording. For example:
3071 =record-started,thread-group="i1",method="btrace",format="bts"
3073 * MI async record =thread-selected now includes the frame field. For example:
3075 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
3079 Andes NDS32 nds32*-*-elf
3081 *** Changes in GDB 7.11
3083 * GDB now supports debugging kernel-based threads on FreeBSD.
3085 * Per-inferior thread numbers
3087 Thread numbers are now per inferior instead of global. If you're
3088 debugging multiple inferiors, GDB displays thread IDs using a
3089 qualified INF_NUM.THR_NUM form. For example:
3093 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
3094 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
3095 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
3096 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
3098 As consequence, thread numbers as visible in the $_thread
3099 convenience variable and in Python's InferiorThread.num attribute
3100 are no longer unique between inferiors.
3102 GDB now maintains a second thread ID per thread, referred to as the
3103 global thread ID, which is the new equivalent of thread numbers in
3104 previous releases. See also $_gthread below.
3106 For backwards compatibility, MI's thread IDs always refer to global
3109 * Commands that accept thread IDs now accept the qualified
3110 INF_NUM.THR_NUM form as well. For example:
3113 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
3116 * In commands that accept a list of thread IDs, you can now refer to
3117 all threads of an inferior using a star wildcard. GDB accepts
3118 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
3119 refer to all threads of the current inferior. For example, "info
3122 * You can use "info threads -gid" to display the global thread ID of
3125 * The new convenience variable $_gthread holds the global number of
3128 * The new convenience variable $_inferior holds the number of the
3131 * GDB now displays the ID and name of the thread that hit a breakpoint
3132 or received a signal, if your program is multi-threaded. For
3135 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
3136 Thread 1 "main" received signal SIGINT, Interrupt.
3138 * Record btrace now supports non-stop mode.
3140 * Support for tracepoints on aarch64-linux was added in GDBserver.
3142 * The 'record instruction-history' command now indicates speculative execution
3143 when using the Intel Processor Trace recording format.
3145 * GDB now allows users to specify explicit locations, bypassing
3146 the linespec parser. This feature is also available to GDB/MI
3149 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
3150 GDB now is able to debug both AArch64 applications and ARM applications
3153 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
3154 including JIT compiling fast tracepoint's conditional expression bytecode
3157 * GDB now supports displaced stepping on AArch64 GNU/Linux.
3159 * "info threads", "info inferiors", "info display", "info checkpoints"
3160 and "maint info program-spaces" now list the corresponding items in
3161 ascending ID order, for consistency with all other "info" commands.
3163 * In Ada, the overloads selection menu has been enhanced to display the
3164 parameter types and the return types for the matching overloaded subprograms.
3168 maint set target-non-stop (on|off|auto)
3169 maint show target-non-stop
3170 Control whether GDB targets always operate in non-stop mode even if
3171 "set non-stop" is "off". The default is "auto", meaning non-stop
3172 mode is enabled if supported by the target.
3174 maint set bfd-sharing
3175 maint show bfd-sharing
3176 Control the reuse of bfd objects.
3179 show debug bfd-cache
3180 Control display of debugging info regarding bfd caching.
3184 Control display of debugging info regarding FreeBSD threads.
3186 set remote multiprocess-extensions-packet
3187 show remote multiprocess-extensions-packet
3188 Set/show the use of the remote protocol multiprocess extensions.
3190 set remote thread-events
3191 show remote thread-events
3192 Set/show the use of thread create/exit events.
3194 set ada print-signatures on|off
3195 show ada print-signatures"
3196 Control whether parameter types and return types are displayed in overloads
3197 selection menus. It is activated (@code{on}) by default.
3201 Controls the maximum size of memory, in bytes, that GDB will
3202 allocate for value contents. Prevents incorrect programs from
3203 causing GDB to allocate overly large buffers. Default is 64k.
3205 * The "disassemble" command accepts a new modifier: /s.
3206 It prints mixed source+disassembly like /m with two differences:
3207 - disassembled instructions are now printed in program order, and
3208 - and source for all relevant files is now printed.
3209 The "/m" option is now considered deprecated: its "source-centric"
3210 output hasn't proved useful in practice.
3212 * The "record instruction-history" command accepts a new modifier: /s.
3213 It behaves exactly like /m and prints mixed source+disassembly.
3215 * The "set scheduler-locking" command supports a new mode "replay".
3216 It behaves like "off" in record mode and like "on" in replay mode.
3218 * Support for various ROM monitors has been removed:
3220 target dbug dBUG ROM monitor for Motorola ColdFire
3221 target picobug Motorola picobug monitor
3222 target dink32 DINK32 ROM monitor for PowerPC
3223 target m32r Renesas M32R/D ROM monitor
3224 target mon2000 mon2000 ROM monitor
3225 target ppcbug PPCBUG ROM monitor for PowerPC
3227 * Support for reading/writing memory and extracting values on architectures
3228 whose memory is addressable in units of any integral multiple of 8 bits.
3231 Allows to break when an Ada exception is handled.
3233 * New remote packets
3236 Indicates that an exec system call was executed.
3238 exec-events feature in qSupported
3239 The qSupported packet allows GDB to request support for exec
3240 events using the new 'gdbfeature' exec-event, and the qSupported
3241 response can contain the corresponding 'stubfeature'. Set and
3242 show commands can be used to display whether these features are enabled.
3245 Equivalent to interrupting with the ^C character, but works in
3248 thread created stop reason (T05 create:...)
3249 Indicates that the thread was just created and is stopped at entry.
3251 thread exit stop reply (w exitcode;tid)
3252 Indicates that the thread has terminated.
3255 Enables/disables thread create and exit event reporting. For
3256 example, this is used in non-stop mode when GDB stops a set of
3257 threads and synchronously waits for the their corresponding stop
3258 replies. Without exit events, if one of the threads exits, GDB
3259 would hang forever not knowing that it should no longer expect a
3260 stop for that same thread.
3263 Indicates that there are no resumed threads left in the target (all
3264 threads are stopped). The remote stub reports support for this stop
3265 reply to GDB's qSupported query.
3268 Enables/disables catching syscalls from the inferior process.
3269 The remote stub reports support for this packet to GDB's qSupported query.
3271 syscall_entry stop reason
3272 Indicates that a syscall was just called.
3274 syscall_return stop reason
3275 Indicates that a syscall just returned.
3277 * Extended-remote exec events
3279 ** GDB now has support for exec events on extended-remote Linux targets.
3280 For such targets with Linux kernels 2.5.46 and later, this enables
3281 follow-exec-mode and exec catchpoints.
3283 set remote exec-event-feature-packet
3284 show remote exec-event-feature-packet
3285 Set/show the use of the remote exec event feature.
3287 * Thread names in remote protocol
3289 The reply to qXfer:threads:read may now include a name attribute for each
3292 * Target remote mode fork and exec events
3294 ** GDB now has support for fork and exec events on target remote mode
3295 Linux targets. For such targets with Linux kernels 2.5.46 and later,
3296 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
3297 fork and exec catchpoints.
3299 * Remote syscall events
3301 ** GDB now has support for catch syscall on remote Linux targets,
3302 currently enabled on x86/x86_64 architectures.
3304 set remote catch-syscall-packet
3305 show remote catch-syscall-packet
3306 Set/show the use of the remote catch syscall feature.
3310 ** The -var-set-format command now accepts the zero-hexadecimal
3311 format. It outputs data in hexadecimal format with zero-padding on the
3316 ** gdb.InferiorThread objects have a new attribute "global_num",
3317 which refers to the thread's global thread ID. The existing
3318 "num" attribute now refers to the thread's per-inferior number.
3319 See "Per-inferior thread numbers" above.
3320 ** gdb.InferiorThread objects have a new attribute "inferior", which
3321 is the Inferior object the thread belongs to.
3323 *** Changes in GDB 7.10
3325 * Support for process record-replay and reverse debugging on aarch64*-linux*
3326 targets has been added. GDB now supports recording of A64 instruction set
3327 including advance SIMD instructions.
3329 * Support for Sun's version of the "stabs" debug file format has been removed.
3331 * GDB now honors the content of the file /proc/PID/coredump_filter
3332 (PID is the process ID) on GNU/Linux systems. This file can be used
3333 to specify the types of memory mappings that will be included in a
3334 corefile. For more information, please refer to the manual page of
3335 "core(5)". GDB also has a new command: "set use-coredump-filter
3336 on|off". It allows to set whether GDB will read the content of the
3337 /proc/PID/coredump_filter file when generating a corefile.
3339 * The "info os" command on GNU/Linux can now display information on
3341 "info os cpus" Listing of all cpus/cores on the system
3343 * GDB has two new commands: "set serial parity odd|even|none" and
3344 "show serial parity". These allows to set or show parity for the
3347 * The "info source" command now displays the producer string if it was
3348 present in the debug info. This typically includes the compiler version
3349 and may include things like its command line arguments.
3351 * The "info dll", an alias of the "info sharedlibrary" command,
3352 is now available on all platforms.
3354 * Directory names supplied to the "set sysroot" commands may be
3355 prefixed with "target:" to tell GDB to access shared libraries from
3356 the target system, be it local or remote. This replaces the prefix
3357 "remote:". The default sysroot has been changed from "" to
3358 "target:". "remote:" is automatically converted to "target:" for
3359 backward compatibility.
3361 * The system root specified by "set sysroot" will be prepended to the
3362 filename of the main executable (if reported to GDB as absolute by
3363 the operating system) when starting processes remotely, and when
3364 attaching to already-running local or remote processes.
3366 * GDB now supports automatic location and retrieval of executable
3367 files from remote targets. Remote debugging can now be initiated
3368 using only a "target remote" or "target extended-remote" command
3369 (no "set sysroot" or "file" commands are required). See "New remote
3372 * The "dump" command now supports verilog hex format.
3374 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
3376 * On GNU/Linux, GDB and gdbserver are now able to access executable
3377 and shared library files without a "set sysroot" command when
3378 attaching to processes running in different mount namespaces from
3379 the debugger. This makes it possible to attach to processes in
3380 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
3381 See "New remote packets" below.
3383 * The "tui reg" command now provides completion for all of the
3384 available register groups, including target specific groups.
3386 * The HISTSIZE environment variable is no longer read when determining
3387 the size of GDB's command history. GDB now instead reads the dedicated
3388 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
3389 disables truncation of command history. Non-numeric values of GDBHISTSIZE
3394 ** Memory ports can now be unbuffered.
3398 ** gdb.Objfile objects have a new attribute "username",
3399 which is the name of the objfile as specified by the user,
3400 without, for example, resolving symlinks.
3401 ** You can now write frame unwinders in Python.
3402 ** gdb.Type objects have a new method "optimized_out",
3403 returning optimized out gdb.Value instance of this type.
3404 ** gdb.Value objects have new methods "reference_value" and
3405 "const_value" which return a reference to the value and a
3406 "const" version of the value respectively.
3410 maint print symbol-cache
3411 Print the contents of the symbol cache.
3413 maint print symbol-cache-statistics
3414 Print statistics of symbol cache usage.
3416 maint flush-symbol-cache
3417 Flush the contents of the symbol cache.
3421 Start branch trace recording using Branch Trace Store (BTS) format.
3424 Evaluate expression by using the compiler and print result.
3428 Explicit commands for enabling and disabling tui mode.
3431 set mpx bound on i386 and amd64
3432 Support for bound table investigation on Intel MPX enabled applications.
3436 Start branch trace recording using Intel Processor Trace format.
3439 Print information about branch tracing internals.
3441 maint btrace packet-history
3442 Print the raw branch tracing data.
3444 maint btrace clear-packet-history
3445 Discard the stored raw branch tracing data.
3448 Discard all branch tracing data. It will be fetched and processed
3449 anew by the next "record" command.
3454 Renamed from "set debug dwarf2-die".
3455 show debug dwarf-die
3456 Renamed from "show debug dwarf2-die".
3458 set debug dwarf-read
3459 Renamed from "set debug dwarf2-read".
3460 show debug dwarf-read
3461 Renamed from "show debug dwarf2-read".
3463 maint set dwarf always-disassemble
3464 Renamed from "maint set dwarf2 always-disassemble".
3465 maint show dwarf always-disassemble
3466 Renamed from "maint show dwarf2 always-disassemble".
3468 maint set dwarf max-cache-age
3469 Renamed from "maint set dwarf2 max-cache-age".
3470 maint show dwarf max-cache-age
3471 Renamed from "maint show dwarf2 max-cache-age".
3473 set debug dwarf-line
3474 show debug dwarf-line
3475 Control display of debugging info regarding DWARF line processing.
3478 show max-completions
3479 Set the maximum number of candidates to be considered during
3480 completion. The default value is 200. This limit allows GDB
3481 to avoid generating large completion lists, the computation of
3482 which can cause the debugger to become temporarily unresponsive.
3484 set history remove-duplicates
3485 show history remove-duplicates
3486 Control the removal of duplicate history entries.
3488 maint set symbol-cache-size
3489 maint show symbol-cache-size
3490 Control the size of the symbol cache.
3492 set|show record btrace bts buffer-size
3493 Set and show the size of the ring buffer used for branch tracing in
3495 The obtained size may differ from the requested size. Use "info
3496 record" to see the obtained buffer size.
3498 set debug linux-namespaces
3499 show debug linux-namespaces
3500 Control display of debugging info regarding Linux namespaces.
3502 set|show record btrace pt buffer-size
3503 Set and show the size of the ring buffer used for branch tracing in
3504 Intel Processor Trace format.
3505 The obtained size may differ from the requested size. Use "info
3506 record" to see the obtained buffer size.
3508 maint set|show btrace pt skip-pad
3509 Set and show whether PAD packets are skipped when computing the
3512 * The command 'thread apply all' can now support new option '-ascending'
3513 to call its specified command for all threads in ascending order.
3515 * Python/Guile scripting
3517 ** GDB now supports auto-loading of Python/Guile scripts contained in the
3518 special section named `.debug_gdb_scripts'.
3520 * New remote packets
3522 qXfer:btrace-conf:read
3523 Return the branch trace configuration for the current thread.
3525 Qbtrace-conf:bts:size
3526 Set the requested ring buffer size for branch tracing in BTS format.
3529 Enable Intel Processor Trace-based branch tracing for the current
3530 process. The remote stub reports support for this packet to GDB's
3533 Qbtrace-conf:pt:size
3534 Set the requested ring buffer size for branch tracing in Intel Processor
3538 Indicates a memory breakpoint instruction was executed, irrespective
3539 of whether it was GDB that planted the breakpoint or the breakpoint
3540 is hardcoded in the program. This is required for correct non-stop
3544 Indicates the target stopped for a hardware breakpoint. This is
3545 required for correct non-stop mode operation.
3548 Return information about files on the remote system.
3550 qXfer:exec-file:read
3551 Return the full absolute name of the file that was executed to
3552 create a process running on the remote system.
3555 Select the filesystem on which vFile: operations with filename
3556 arguments will operate. This is required for GDB to be able to
3557 access files on remote targets where the remote stub does not
3558 share a common filesystem with the inferior(s).
3561 Indicates that a fork system call was executed.
3564 Indicates that a vfork system call was executed.
3566 vforkdone stop reason
3567 Indicates that a vfork child of the specified process has executed
3568 an exec or exit, allowing the vfork parent to resume execution.
3570 fork-events and vfork-events features in qSupported
3571 The qSupported packet allows GDB to request support for fork and
3572 vfork events using new 'gdbfeatures' fork-events and vfork-events,
3573 and the qSupported response can contain the corresponding
3574 'stubfeatures'. Set and show commands can be used to display
3575 whether these features are enabled.
3577 * Extended-remote fork events
3579 ** GDB now has support for fork events on extended-remote Linux
3580 targets. For targets with Linux kernels 2.5.60 and later, this
3581 enables follow-fork-mode and detach-on-fork for both fork and
3582 vfork, as well as fork and vfork catchpoints.
3584 * The info record command now shows the recording format and the
3585 branch tracing configuration for the current thread when using
3586 the btrace record target.
3587 For the BTS format, it shows the ring buffer size.
3589 * GDB now has support for DTrace USDT (Userland Static Defined
3590 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
3592 * GDB now supports access to vector registers on S/390 GNU/Linux
3595 * Removed command line options
3597 -xdb HP-UX XDB compatibility mode.
3599 * Removed targets and native configurations
3601 HP/PA running HP-UX hppa*-*-hpux*
3602 Itanium running HP-UX ia64-*-hpux*
3604 * New configure options
3607 This configure option allows the user to build GDB with support for
3608 Intel Processor Trace (default: auto). This requires libipt.
3610 --with-libipt-prefix=PATH
3611 Specify the path to the version of libipt that GDB should use.
3612 $PATH/include should contain the intel-pt.h header and
3613 $PATH/lib should contain the libipt.so library.
3615 *** Changes in GDB 7.9.1
3619 ** Xmethods can now specify a result type.
3621 *** Changes in GDB 7.9
3623 * GDB now supports hardware watchpoints on x86 GNU Hurd.
3627 ** You can now access frame registers from Python scripts.
3628 ** New attribute 'producer' for gdb.Symtab objects.
3629 ** gdb.Objfile objects have a new attribute "progspace",
3630 which is the gdb.Progspace object of the containing program space.
3631 ** gdb.Objfile objects have a new attribute "owner".
3632 ** gdb.Objfile objects have a new attribute "build_id",
3633 which is the build ID generated when the file was built.
3634 ** gdb.Objfile objects have a new method "add_separate_debug_file".
3635 ** A new event "gdb.clear_objfiles" has been added, triggered when
3636 selecting a new file to debug.
3637 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
3638 ** New function gdb.lookup_objfile.
3640 New events which are triggered when GDB modifies the state of the
3643 ** gdb.events.inferior_call_pre: Function call is about to be made.
3644 ** gdb.events.inferior_call_post: Function call has just been made.
3645 ** gdb.events.memory_changed: A memory location has been altered.
3646 ** gdb.events.register_changed: A register has been altered.
3648 * New Python-based convenience functions:
3650 ** $_caller_is(name [, number_of_frames])
3651 ** $_caller_matches(regexp [, number_of_frames])
3652 ** $_any_caller_is(name [, number_of_frames])
3653 ** $_any_caller_matches(regexp [, number_of_frames])
3655 * GDB now supports the compilation and injection of source code into
3656 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
3657 to compile the source code to object code, and if successful, inject
3658 and execute that code within the current context of the inferior.
3659 Currently the C language is supported. The commands used to
3660 interface with this new feature are:
3662 compile code [-raw|-r] [--] [source code]
3663 compile file [-raw|-r] filename
3667 demangle [-l language] [--] name
3668 Demangle "name" in the specified language, or the current language
3669 if elided. This command is renamed from the "maint demangle" command.
3670 The latter is kept as a no-op to avoid "maint demangle" being interpreted
3671 as "maint demangler-warning".
3673 queue-signal signal-name-or-number
3674 Queue a signal to be delivered to the thread when it is resumed.
3676 add-auto-load-scripts-directory directory
3677 Add entries to the list of directories from which to load auto-loaded
3680 maint print user-registers
3681 List all currently available "user" registers.
3683 compile code [-r|-raw] [--] [source code]
3684 Compile, inject, and execute in the inferior the executable object
3685 code produced by compiling the provided source code.
3687 compile file [-r|-raw] filename
3688 Compile and inject into the inferior the executable object code
3689 produced by compiling the source code stored in the filename
3692 * On resume, GDB now always passes the signal the program had stopped
3693 for to the thread the signal was sent to, even if the user changed
3694 threads before resuming. Previously GDB would often (but not
3695 always) deliver the signal to the thread that happens to be current
3698 * Conversely, the "signal" command now consistently delivers the
3699 requested signal to the current thread. GDB now asks for
3700 confirmation if the program had stopped for a signal and the user
3701 switched threads meanwhile.
3703 * "breakpoint always-inserted" modes "off" and "auto" merged.
3705 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
3706 won't remove breakpoints from the target until all threads stop,
3707 even in non-stop mode. The "auto" mode has been removed, and "off"
3708 is now the default mode.
3712 set debug symbol-lookup
3713 show debug symbol-lookup
3714 Control display of debugging info regarding symbol lookup.
3718 ** The -list-thread-groups command outputs an exit-code field for
3719 inferiors that have exited.
3723 MIPS SDE mips*-sde*-elf*
3727 Support for these obsolete configurations has been removed.
3729 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
3730 SGI Irix-5.x mips-*-irix5*
3731 SGI Irix-6.x mips-*-irix6*
3732 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
3733 VAX running Ultrix vax-*-ultrix*
3735 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
3736 and "assf"), have been removed. Use the "sharedlibrary" command, or
3737 its alias "share", instead.
3739 *** Changes in GDB 7.8
3741 * New command line options
3744 This is an alias for the --data-directory option.
3746 * GDB supports printing and modifying of variable length automatic arrays
3747 as specified in ISO C99.
3749 * The ARM simulator now supports instruction level tracing
3750 with or without disassembly.
3754 GDB now has support for scripting using Guile. Whether this is
3755 available is determined at configure time.
3756 Guile version 2.0 or greater is required.
3757 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
3759 * New commands (for set/show, see "New options" below)
3763 Invoke CODE by passing it to the Guile interpreter.
3767 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
3769 info auto-load guile-scripts [regexp]
3770 Print the list of automatically loaded Guile scripts.
3772 * The source command is now capable of sourcing Guile scripts.
3773 This feature is dependent on the debugger being built with Guile support.
3777 set print symbol-loading (off|brief|full)
3778 show print symbol-loading
3779 Control whether to print informational messages when loading symbol
3780 information for a file. The default is "full", but when debugging
3781 programs with large numbers of shared libraries the amount of output
3782 becomes less useful.
3784 set guile print-stack (none|message|full)
3785 show guile print-stack
3786 Show a stack trace when an error is encountered in a Guile script.
3788 set auto-load guile-scripts (on|off)
3789 show auto-load guile-scripts
3790 Control auto-loading of Guile script files.
3792 maint ada set ignore-descriptive-types (on|off)
3793 maint ada show ignore-descriptive-types
3794 Control whether the debugger should ignore descriptive types in Ada
3795 programs. The default is not to ignore the descriptive types. See
3796 the user manual for more details on descriptive types and the intended
3797 usage of this option.
3799 set auto-connect-native-target
3801 Control whether GDB is allowed to automatically connect to the
3802 native target for the run, attach, etc. commands when not connected
3803 to any target yet. See also "target native" below.
3805 set record btrace replay-memory-access (read-only|read-write)
3806 show record btrace replay-memory-access
3807 Control what memory accesses are allowed during replay.
3809 maint set target-async (on|off)
3810 maint show target-async
3811 This controls whether GDB targets operate in synchronous or
3812 asynchronous mode. Normally the default is asynchronous, if it is
3813 available; but this can be changed to more easily debug problems
3814 occurring only in synchronous mode.
3816 set mi-async (on|off)
3818 Control whether MI asynchronous mode is preferred. This supersedes
3819 "set target-async" of previous GDB versions.
3821 * "set target-async" is deprecated as a CLI option and is now an alias
3822 for "set mi-async" (only puts MI into async mode).
3824 * Background execution commands (e.g., "c&", "s&", etc.) are now
3825 possible ``out of the box'' if the target supports them. Previously
3826 the user would need to explicitly enable the possibility with the
3827 "set target-async on" command.
3829 * New features in the GDB remote stub, GDBserver
3831 ** New option --debug-format=option1[,option2,...] allows one to add
3832 additional text to each output. At present only timestamps
3833 are supported: --debug-format=timestamps.
3834 Timestamps can also be turned on with the
3835 "monitor set debug-format timestamps" command from GDB.
3837 * The 'record instruction-history' command now starts counting instructions
3838 at one. This also affects the instruction ranges reported by the
3839 'record function-call-history' command when given the /i modifier.
3841 * The command 'record function-call-history' supports a new modifier '/c' to
3842 indent the function names based on their call stack depth.
3843 The fields for the '/i' and '/l' modifier have been reordered.
3844 The source line range is now prefixed with 'at'.
3845 The instruction range is now prefixed with 'inst'.
3846 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
3847 "record instruction-history" and "list" commands.
3849 * The ranges given as arguments to the 'record function-call-history' and
3850 'record instruction-history' commands are now inclusive.
3852 * The btrace record target now supports the 'record goto' command.
3853 For locations inside the execution trace, the back trace is computed
3854 based on the information stored in the execution trace.
3856 * The btrace record target supports limited reverse execution and replay.
3857 The target does not record data and therefore does not allow reading
3858 memory or registers.
3860 * The "catch syscall" command now works on s390*-linux* targets.
3862 * The "compare-sections" command is no longer specific to target
3863 remote. It now works with all targets.
3865 * All native targets are now consistently called "native".
3866 Consequently, the "target child", "target GNU", "target djgpp",
3867 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
3868 commands have been replaced with "target native". The QNX/NTO port
3869 leaves the "procfs" target in place and adds a "native" target for
3870 consistency with other ports. The impact on users should be minimal
3871 as these commands previously either throwed an error, or were
3872 no-ops. The target's name is visible in the output of the following
3873 commands: "help target", "info target", "info files", "maint print
3876 * The "target native" command now connects to the native target. This
3877 can be used to launch native programs even when "set
3878 auto-connect-native-target" is set to off.
3880 * GDB now supports access to Intel MPX registers on GNU/Linux.
3882 * Support for Intel AVX-512 registers on GNU/Linux.
3883 Support displaying and modifying Intel AVX-512 registers
3884 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
3886 * New remote packets
3888 qXfer:btrace:read's annex
3889 The qXfer:btrace:read packet supports a new annex 'delta' to read
3890 branch trace incrementally.
3894 ** Valid Python operations on gdb.Value objects representing
3895 structs/classes invoke the corresponding overloaded operators if
3897 ** New `Xmethods' feature in the Python API. Xmethods are
3898 additional methods or replacements for existing methods of a C++
3899 class. This feature is useful for those cases where a method
3900 defined in C++ source code could be inlined or optimized out by
3901 the compiler, making it unavailable to GDB.
3904 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
3906 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
3907 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
3908 its alias "share", instead.
3910 * The commands "set remotebaud" and "show remotebaud" are no longer
3911 supported. Use "set serial baud" and "show serial baud" (respectively)
3916 ** A new option "-gdb-set mi-async" replaces "-gdb-set
3917 target-async". The latter is left as a deprecated alias of the
3918 former for backward compatibility. If the target supports it,
3919 CLI background execution commands are now always possible by
3920 default, independently of whether the frontend stated a
3921 preference for asynchronous execution with "-gdb-set mi-async".
3922 Previously "-gdb-set target-async off" affected both MI execution
3923 commands and CLI execution commands.
3925 *** Changes in GDB 7.7
3927 * Improved support for process record-replay and reverse debugging on
3928 arm*-linux* targets. Support for thumb32 and syscall instruction
3929 recording has been added.
3931 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
3933 * GDB now supports Fission DWP file format version 2.
3934 http://gcc.gnu.org/wiki/DebugFission
3936 * New convenience function "$_isvoid", to check whether an expression
3937 is void. A void expression is an expression where the type of the
3938 result is "void". For example, some convenience variables may be
3939 "void" when evaluated (e.g., "$_exitcode" before the execution of
3940 the program being debugged; or an undefined convenience variable).
3941 Another example, when calling a function whose return type is
3944 * The "maintenance print objfiles" command now takes an optional regexp.
3946 * The "catch syscall" command now works on arm*-linux* targets.
3948 * GDB now consistently shows "<not saved>" when printing values of
3949 registers the debug info indicates have not been saved in the frame
3950 and there's nowhere to retrieve them from
3951 (callee-saved/call-clobbered registers):
3956 (gdb) info registers rax
3959 Before, the former would print "<optimized out>", and the latter
3960 "*value not available*".
3962 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
3967 ** Frame filters and frame decorators have been added.
3968 ** Temporary breakpoints are now supported.
3969 ** Line tables representation has been added.
3970 ** New attribute 'parent_type' for gdb.Field objects.
3971 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
3972 ** New attribute 'name' for gdb.Type objects.
3976 Nios II ELF nios2*-*-elf
3977 Nios II GNU/Linux nios2*-*-linux
3978 Texas Instruments MSP430 msp430*-*-elf
3980 * Removed native configurations
3982 Support for these a.out NetBSD and OpenBSD obsolete configurations has
3983 been removed. ELF variants of these configurations are kept supported.
3985 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
3986 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
3987 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
3988 i[34567]86-*-openbsd3.[0-3]
3989 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
3990 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
3991 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
3995 Like "catch throw", but catches a re-thrown exception.
3996 maint check-psymtabs
3997 Renamed from old "maint check-symtabs".
3999 Perform consistency checks on symtabs.
4000 maint expand-symtabs
4001 Expand symtabs matching an optional regexp.
4004 Display the details of GDB configure-time options.
4006 maint set|show per-command
4007 maint set|show per-command space
4008 maint set|show per-command time
4009 maint set|show per-command symtab
4010 Enable display of per-command gdb resource usage.
4012 remove-symbol-file FILENAME
4013 remove-symbol-file -a ADDRESS
4014 Remove a symbol file added via add-symbol-file. The file to remove
4015 can be identified by its filename or by an address that lies within
4016 the boundaries of this symbol file in memory.
4019 info exceptions REGEXP
4020 Display the list of Ada exceptions defined in the program being
4021 debugged. If provided, only the exceptions whose names match REGEXP
4026 set debug symfile off|on
4028 Control display of debugging info regarding reading symbol files and
4029 symbol tables within those files
4031 set print raw frame-arguments
4032 show print raw frame-arguments
4033 Set/show whether to print frame arguments in raw mode,
4034 disregarding any defined pretty-printers.
4036 set remote trace-status-packet
4037 show remote trace-status-packet
4038 Set/show the use of remote protocol qTStatus packet.
4042 Control display of debugging messages related to Nios II targets.
4046 Control whether target-assisted range stepping is enabled.
4048 set startup-with-shell
4049 show startup-with-shell
4050 Specifies whether Unix child processes are started via a shell or
4055 Use the target memory cache for accesses to the code segment. This
4056 improves performance of remote debugging (particularly disassembly).
4058 * You can now use a literal value 'unlimited' for options that
4059 interpret 0 or -1 as meaning "unlimited". E.g., "set
4060 trace-buffer-size unlimited" is now an alias for "set
4061 trace-buffer-size -1" and "set height unlimited" is now an alias for
4064 * The "set debug symtab-create" debugging option of GDB has been changed to
4065 accept a verbosity level. 0 means "off", 1 provides basic debugging
4066 output, and values of 2 or greater provides more verbose output.
4068 * New command-line options
4070 Display the details of GDB configure-time options.
4072 * The command 'tsave' can now support new option '-ctf' to save trace
4073 buffer in Common Trace Format.
4075 * Newly installed $prefix/bin/gcore acts as a shell interface for the
4078 * GDB now implements the C++ 'typeid' operator.
4080 * The new convenience variable $_exception holds the exception being
4081 thrown or caught at an exception-related catchpoint.
4083 * The exception-related catchpoints, like "catch throw", now accept a
4084 regular expression which can be used to filter exceptions by type.
4086 * The new convenience variable $_exitsignal is automatically set to
4087 the terminating signal number when the program being debugged dies
4088 due to an uncaught signal.
4092 ** All MI commands now accept an optional "--language" option.
4093 Support for this feature can be verified by using the "-list-features"
4094 command, which should contain "language-option".
4096 ** The new command -info-gdb-mi-command allows the user to determine
4097 whether a GDB/MI command is supported or not.
4099 ** The "^error" result record returned when trying to execute an undefined
4100 GDB/MI command now provides a variable named "code" whose content is the
4101 "undefined-command" error code. Support for this feature can be verified
4102 by using the "-list-features" command, which should contain
4103 "undefined-command-error-code".
4105 ** The -trace-save MI command can optionally save trace buffer in Common
4108 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
4110 ** The command -data-list-register-values now accepts an optional
4111 "--skip-unavailable" option. When used, only the available registers
4114 ** The new command -trace-frame-collected dumps collected variables,
4115 computed expressions, tvars, memory and registers in a traceframe.
4117 ** The commands -stack-list-locals, -stack-list-arguments and
4118 -stack-list-variables now accept an option "--skip-unavailable".
4119 When used, only the available locals or arguments are displayed.
4121 ** The -exec-run command now accepts an optional "--start" option.
4122 When used, the command follows the same semantics as the "start"
4123 command, stopping the program's execution at the start of its
4124 main subprogram. Support for this feature can be verified using
4125 the "-list-features" command, which should contain
4126 "exec-run-start-option".
4128 ** The new commands -catch-assert and -catch-exceptions insert
4129 catchpoints stopping the program when Ada exceptions are raised.
4131 ** The new command -info-ada-exceptions provides the equivalent of
4132 the new "info exceptions" command.
4134 * New system-wide configuration scripts
4135 A GDB installation now provides scripts suitable for use as system-wide
4136 configuration scripts for the following systems:
4140 * GDB now supports target-assigned range stepping with remote targets.
4141 This improves the performance of stepping source lines by reducing
4142 the number of control packets from/to GDB. See "New remote packets"
4145 * GDB now understands the element 'tvar' in the XML traceframe info.
4146 It has the id of the collected trace state variables.
4148 * On S/390 targets that provide the transactional-execution feature,
4149 the program interruption transaction diagnostic block (TDB) is now
4150 represented as a number of additional "registers" in GDB.
4152 * New remote packets
4156 The vCont packet supports a new 'r' action, that tells the remote
4157 stub to step through an address range itself, without GDB
4158 involvemement at each single-step.
4160 qXfer:libraries-svr4:read's annex
4161 The previously unused annex of the qXfer:libraries-svr4:read packet
4162 is now used to support passing an argument list. The remote stub
4163 reports support for this argument list to GDB's qSupported query.
4164 The defined arguments are "start" and "prev", used to reduce work
4165 necessary for library list updating, resulting in significant
4168 * New features in the GDB remote stub, GDBserver
4170 ** GDBserver now supports target-assisted range stepping. Currently
4171 enabled on x86/x86_64 GNU/Linux targets.
4173 ** GDBserver now adds element 'tvar' in the XML in the reply to
4174 'qXfer:traceframe-info:read'. It has the id of the collected
4175 trace state variables.
4177 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
4180 * New 'z' formatter for printing and examining memory, this displays the
4181 value as hexadecimal zero padded on the left to the size of the type.
4183 * GDB can now use Windows x64 unwinding data.
4185 * The "set remotebaud" command has been replaced by "set serial baud".
4186 Similarly, "show remotebaud" has been replaced by "show serial baud".
4187 The "set remotebaud" and "show remotebaud" commands are still available
4188 to provide backward compatibility with older versions of GDB.
4190 *** Changes in GDB 7.6
4192 * Target record has been renamed to record-full.
4193 Record/replay is now enabled with the "record full" command.
4194 This also affects settings that are associated with full record/replay
4195 that have been moved from "set/show record" to "set/show record full":
4197 set|show record full insn-number-max
4198 set|show record full stop-at-limit
4199 set|show record full memory-query
4201 * A new record target "record-btrace" has been added. The new target
4202 uses hardware support to record the control-flow of a process. It
4203 does not support replaying the execution, but it implements the
4204 below new commands for investigating the recorded execution log.
4205 This new recording method can be enabled using:
4209 The "record-btrace" target is only available on Intel Atom processors
4210 and requires a Linux kernel 2.6.32 or later.
4212 * Two new commands have been added for record/replay to give information
4213 about the recorded execution without having to replay the execution.
4214 The commands are only supported by "record btrace".
4216 record instruction-history prints the execution history at
4217 instruction granularity
4219 record function-call-history prints the execution history at
4220 function granularity
4222 * New native configurations
4224 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
4225 FreeBSD/powerpc powerpc*-*-freebsd
4226 x86_64/Cygwin x86_64-*-cygwin*
4227 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
4231 ARM AArch64 aarch64*-*-elf
4232 ARM AArch64 GNU/Linux aarch64*-*-linux
4233 Lynx 178 PowerPC powerpc-*-lynx*178
4234 x86_64/Cygwin x86_64-*-cygwin*
4235 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
4237 * If the configured location of system.gdbinit file (as given by the
4238 --with-system-gdbinit option at configure time) is in the
4239 data-directory (as specified by --with-gdb-datadir at configure
4240 time) or in one of its subdirectories, then GDB will look for the
4241 system-wide init file in the directory specified by the
4242 --data-directory command-line option.
4244 * New command line options:
4246 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
4247 other initialization files, unlike -nx which disables all of them.
4249 * Removed command line options
4251 -epoch This was used by the gdb mode in Epoch, an ancient fork of
4254 * The 'ptype' and 'whatis' commands now accept an argument to control
4257 * 'info proc' now works on some core files.
4261 ** Vectors can be created with gdb.Type.vector.
4263 ** Python's atexit.register now works in GDB.
4265 ** Types can be pretty-printed via a Python API.
4267 ** Python 3 is now supported (in addition to Python 2.4 or later)
4269 ** New class gdb.Architecture exposes GDB's internal representation
4270 of architecture in the Python API.
4272 ** New method Frame.architecture returns the gdb.Architecture object
4273 corresponding to the frame's architecture.
4275 * New Python-based convenience functions:
4277 ** $_memeq(buf1, buf2, length)
4278 ** $_streq(str1, str2)
4280 ** $_regex(str, regex)
4282 * The 'cd' command now defaults to using '~' (the home directory) if not
4285 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
4286 default for GCC since November 2000.
4288 * The command 'forward-search' can now be abbreviated as 'fo'.
4290 * The command 'info tracepoints' can now display 'installed on target'
4291 or 'not installed on target' for each non-pending location of tracepoint.
4293 * New configure options
4295 --enable-libmcheck/--disable-libmcheck
4296 By default, development versions are built with -lmcheck on hosts
4297 that support it, in order to help track memory corruption issues.
4298 Release versions, on the other hand, are built without -lmcheck
4299 by default. The --enable-libmcheck/--disable-libmcheck configure
4300 options allow the user to override that default.
4301 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
4302 This configure option allows the user to build GDB with
4303 libbabeltrace using which GDB can read Common Trace Format data.
4305 * New commands (for set/show, see "New options" below)
4308 Catch signals. This is similar to "handle", but allows commands and
4309 conditions to be attached.
4312 List the BFDs known to GDB.
4314 python-interactive [command]
4316 Start a Python interactive prompt, or evaluate the optional command
4317 and print the result of expressions.
4320 "py" is a new alias for "python".
4322 enable type-printer [name]...
4323 disable type-printer [name]...
4324 Enable or disable type printers.
4328 ** For the Renesas Super-H architecture, the "regs" command has been removed
4329 (has been deprecated in GDB 7.5), and "info all-registers" should be used
4334 set print type methods (on|off)
4335 show print type methods
4336 Control whether method declarations are displayed by "ptype".
4337 The default is to show them.
4339 set print type typedefs (on|off)
4340 show print type typedefs
4341 Control whether typedef definitions are displayed by "ptype".
4342 The default is to show them.
4344 set filename-display basename|relative|absolute
4345 show filename-display
4346 Control the way in which filenames is displayed.
4347 The default is "relative", which preserves previous behavior.
4349 set trace-buffer-size
4350 show trace-buffer-size
4351 Request target to change the size of trace buffer.
4353 set remote trace-buffer-size-packet auto|on|off
4354 show remote trace-buffer-size-packet
4355 Control the use of the remote protocol `QTBuffer:size' packet.
4359 Control display of debugging messages related to ARM AArch64.
4362 set debug coff-pe-read
4363 show debug coff-pe-read
4364 Control display of debugging messages related to reading of COFF/PE
4369 Control display of debugging messages related to Mach-O symbols
4372 set debug notification
4373 show debug notification
4374 Control display of debugging info for async remote notification.
4378 ** Command parameter changes are now notified using new async record
4379 "=cmd-param-changed".
4380 ** Trace frame changes caused by command "tfind" are now notified using
4381 new async record "=traceframe-changed".
4382 ** The creation, deletion and modification of trace state variables
4383 are now notified using new async records "=tsv-created",
4384 "=tsv-deleted" and "=tsv-modified".
4385 ** The start and stop of process record are now notified using new
4386 async record "=record-started" and "=record-stopped".
4387 ** Memory changes are now notified using new async record
4389 ** The data-disassemble command response will include a "fullname" field
4390 containing the absolute file name when source has been requested.
4391 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
4392 command, to allow pattern filling of memory areas.
4393 ** New commands "-catch-load"/"-catch-unload" added for intercepting
4394 library load/unload events.
4395 ** The response to breakpoint commands and breakpoint async records
4396 includes an "installed" field containing a boolean state about each
4397 non-pending tracepoint location is whether installed on target or not.
4398 ** Output of the "-trace-status" command includes a "trace-file" field
4399 containing the name of the trace file being examined. This field is
4400 optional, and only present when examining a trace file.
4401 ** The "fullname" field is now always present along with the "file" field,
4402 even if the file cannot be found by GDB.
4404 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
4405 You must have the LZMA library available when configuring GDB for this
4406 feature to be enabled. For more information, see:
4407 http://fedoraproject.org/wiki/Features/MiniDebugInfo
4409 * New remote packets
4412 Set the size of trace buffer. The remote stub reports support for this
4413 packet to gdb's qSupported query.
4416 Enable Branch Trace Store (BTS)-based branch tracing for the current
4417 thread. The remote stub reports support for this packet to gdb's
4421 Disable branch tracing for the current thread. The remote stub reports
4422 support for this packet to gdb's qSupported query.
4425 Read the traced branches for the current thread. The remote stub
4426 reports support for this packet to gdb's qSupported query.
4428 *** Changes in GDB 7.5
4430 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
4431 for more x32 ABI info.
4433 * GDB now supports access to MIPS DSP registers on Linux targets.
4435 * GDB now supports debugging microMIPS binaries.
4437 * The "info os" command on GNU/Linux can now display information on
4438 several new classes of objects managed by the operating system:
4439 "info os procgroups" lists process groups
4440 "info os files" lists file descriptors
4441 "info os sockets" lists internet-domain sockets
4442 "info os shm" lists shared-memory regions
4443 "info os semaphores" lists semaphores
4444 "info os msg" lists message queues
4445 "info os modules" lists loaded kernel modules
4447 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
4448 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
4449 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
4450 options and inspect the probe arguments using the new $_probe_arg family
4451 of convenience variables. You can obtain more information about SystemTap
4452 in <http://sourceware.org/systemtap/>.
4454 * GDB now supports reversible debugging on ARM, it allows you to
4455 debug basic ARM and THUMB instructions, and provides
4456 record/replay support.
4458 * The option "symbol-reloading" has been deleted as it is no longer used.
4462 ** GDB commands implemented in Python can now be put in command class
4465 ** The "maint set python print-stack on|off" is now deleted.
4467 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
4468 apply "flag enum"-style pretty-printing to any enum.
4470 ** gdb.lookup_symbol can now work when there is no current frame.
4472 ** gdb.Symbol now has a 'line' attribute, holding the line number in
4473 the source at which the symbol was defined.
4475 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
4476 method 'value'. The former indicates whether the symbol needs a
4477 frame in order to compute its value, and the latter computes the
4480 ** A new method 'referenced_value' on gdb.Value objects which can
4481 dereference pointer as well as C++ reference values.
4483 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
4484 which return the global and static blocks (as gdb.Block objects),
4485 of the underlying symbol table, respectively.
4487 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
4488 object associated with a PC value.
4490 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
4491 of the address range occupied by code for the current source line.
4493 * Go language support.
4494 GDB now supports debugging programs written in the Go programming
4497 * GDBserver now supports stdio connections.
4498 E.g. (gdb) target remote | ssh myhost gdbserver - hello
4500 * The binary "gdbtui" can no longer be built or installed.
4501 Use "gdb -tui" instead.
4503 * GDB will now print "flag" enums specially. A flag enum is one where
4504 all the enumerator values have no bits in common when pairwise
4505 "and"ed. When printing a value whose type is a flag enum, GDB will
4506 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
4507 (gdb) print (enum E) 3
4510 * The filename part of a linespec will now match trailing components
4511 of a source file name. For example, "break gcc/expr.c:1000" will
4512 now set a breakpoint in build/gcc/expr.c, but not
4513 build/libcpp/expr.c.
4515 * The "info proc" and "generate-core-file" commands will now also
4516 work on remote targets connected to GDBserver on Linux.
4518 * The command "info catch" has been removed. It has been disabled
4519 since December 2007.
4521 * The "catch exception" and "catch assert" commands now accept
4522 a condition at the end of the command, much like the "break"
4523 command does. For instance:
4525 (gdb) catch exception Constraint_Error if Barrier = True
4527 Previously, it was possible to add a condition to such catchpoints,
4528 but it had to be done as a second step, after the catchpoint had been
4529 created, using the "condition" command.
4531 * The "info static-tracepoint-marker" command will now also work on
4532 native Linux targets with in-process agent.
4534 * GDB can now set breakpoints on inlined functions.
4536 * The .gdb_index section has been updated to include symbols for
4537 inlined functions. GDB will ignore older .gdb_index sections by
4538 default, which could cause symbol files to be loaded more slowly
4539 until their .gdb_index sections can be recreated. The new command
4540 "set use-deprecated-index-sections on" will cause GDB to use any older
4541 .gdb_index sections it finds. This will restore performance, but the
4542 ability to set breakpoints on inlined functions will be lost in symbol
4543 files with older .gdb_index sections.
4545 The .gdb_index section has also been updated to record more information
4546 about each symbol. This speeds up the "info variables", "info functions"
4547 and "info types" commands when used with programs having the .gdb_index
4548 section, as well as speeding up debugging with shared libraries using
4549 the .gdb_index section.
4551 * Ada support for GDB/MI Variable Objects has been added.
4553 * GDB can now support 'breakpoint always-inserted mode' in 'record'
4558 ** New command -info-os is the MI equivalent of "info os".
4560 ** Output logs ("set logging" and related) now include MI output.
4564 ** "set use-deprecated-index-sections on|off"
4565 "show use-deprecated-index-sections on|off"
4566 Controls the use of deprecated .gdb_index sections.
4568 ** "catch load" and "catch unload" can be used to stop when a shared
4569 library is loaded or unloaded, respectively.
4571 ** "enable count" can be used to auto-disable a breakpoint after
4574 ** "info vtbl" can be used to show the virtual method tables for
4575 C++ and Java objects.
4577 ** "explore" and its sub commands "explore value" and "explore type"
4578 can be used to recursively explore values and types of
4579 expressions. These commands are available only if GDB is
4580 configured with '--with-python'.
4582 ** "info auto-load" shows status of all kinds of auto-loaded files,
4583 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
4584 sequences of commands files, "info auto-load python-scripts"
4585 shows status of auto-loading Python script files,
4586 "info auto-load local-gdbinit" shows status of loading init file
4587 (.gdbinit) from current directory and "info auto-load libthread-db" shows
4588 status of inferior specific thread debugging shared library loading.
4590 ** "info auto-load-scripts", "set auto-load-scripts on|off"
4591 and "show auto-load-scripts" commands have been deprecated, use their
4592 "info auto-load python-scripts", "set auto-load python-scripts on|off"
4593 and "show auto-load python-scripts" counterparts instead.
4595 ** "dprintf location,format,args..." creates a dynamic printf, which
4596 is basically a breakpoint that does a printf and immediately
4597 resumes your program's execution, so it is like a printf that you
4598 can insert dynamically at runtime instead of at compiletime.
4600 ** "set print symbol"
4602 Controls whether GDB attempts to display the symbol, if any,
4603 corresponding to addresses it prints. This defaults to "on", but
4604 you can set it to "off" to restore GDB's previous behavior.
4606 * Deprecated commands
4608 ** For the Renesas Super-H architecture, the "regs" command has been
4609 deprecated, and "info all-registers" should be used instead.
4613 Renesas RL78 rl78-*-elf
4614 HP OpenVMS ia64 ia64-hp-openvms*
4616 * GDBserver supports evaluation of breakpoint conditions. When
4617 support is advertised by GDBserver, GDB may be told to send the
4618 breakpoint conditions in bytecode form to GDBserver. GDBserver
4619 will only report the breakpoint trigger to GDB when its condition
4624 set mips compression
4625 show mips compression
4626 Select the compressed ISA encoding used in functions that have no symbol
4627 information available. The encoding can be set to either of:
4630 and is updated automatically from ELF file flags if available.
4632 set breakpoint condition-evaluation
4633 show breakpoint condition-evaluation
4634 Control whether breakpoint conditions are evaluated by GDB ("host") or by
4635 GDBserver ("target"). Default option "auto" chooses the most efficient
4637 This option can improve debugger efficiency depending on the speed of the
4641 Disable auto-loading globally.
4644 Show auto-loading setting of all kinds of auto-loaded files.
4646 set auto-load gdb-scripts on|off
4647 show auto-load gdb-scripts
4648 Control auto-loading of GDB canned sequences of commands files.
4650 set auto-load python-scripts on|off
4651 show auto-load python-scripts
4652 Control auto-loading of Python script files.
4654 set auto-load local-gdbinit on|off
4655 show auto-load local-gdbinit
4656 Control loading of init file (.gdbinit) from current directory.
4658 set auto-load libthread-db on|off
4659 show auto-load libthread-db
4660 Control auto-loading of inferior specific thread debugging shared library.
4662 set auto-load scripts-directory <dir1>[:<dir2>...]
4663 show auto-load scripts-directory
4664 Set a list of directories from which to load auto-loaded scripts.
4665 Automatically loaded Python scripts and GDB scripts are located in one
4666 of the directories listed by this option.
4667 The delimiter (':' above) may differ according to the host platform.
4669 set auto-load safe-path <dir1>[:<dir2>...]
4670 show auto-load safe-path
4671 Set a list of directories from which it is safe to auto-load files.
4672 The delimiter (':' above) may differ according to the host platform.
4674 set debug auto-load on|off
4675 show debug auto-load
4676 Control display of debugging info for auto-loading the files above.
4678 set dprintf-style gdb|call|agent
4680 Control the way in which a dynamic printf is performed; "gdb"
4681 requests a GDB printf command, while "call" causes dprintf to call a
4682 function in the inferior. "agent" requests that the target agent
4683 (such as GDBserver) do the printing.
4685 set dprintf-function <expr>
4686 show dprintf-function
4687 set dprintf-channel <expr>
4688 show dprintf-channel
4689 Set the function and optional first argument to the call when using
4690 the "call" style of dynamic printf.
4692 set disconnected-dprintf on|off
4693 show disconnected-dprintf
4694 Control whether agent-style dynamic printfs continue to be in effect
4695 after GDB disconnects.
4697 * New configure options
4699 --with-auto-load-dir
4700 Configure default value for the 'set auto-load scripts-directory'
4701 setting above. It defaults to '$debugdir:$datadir/auto-load',
4702 $debugdir representing global debugging info directories (available
4703 via 'show debug-file-directory') and $datadir representing GDB's data
4704 directory (available via 'show data-directory').
4706 --with-auto-load-safe-path
4707 Configure default value for the 'set auto-load safe-path' setting
4708 above. It defaults to the --with-auto-load-dir setting.
4710 --without-auto-load-safe-path
4711 Set 'set auto-load safe-path' to '/', effectively disabling this
4714 * New remote packets
4716 z0/z1 conditional breakpoints extension
4718 The z0/z1 breakpoint insertion packets have been extended to carry
4719 a list of conditional expressions over to the remote stub depending on the
4720 condition evaluation mode. The use of this extension can be controlled
4721 via the "set remote conditional-breakpoints-packet" command.
4725 Specify the signals which the remote stub may pass to the debugged
4726 program without GDB involvement.
4728 * New command line options
4730 --init-command=FILE, -ix Like --command, -x but execute it
4731 before loading inferior.
4732 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
4733 execute it before loading inferior.
4735 *** Changes in GDB 7.4
4737 * GDB now handles ambiguous linespecs more consistently; the existing
4738 FILE:LINE support has been expanded to other types of linespecs. A
4739 breakpoint will now be set on all matching locations in all
4740 inferiors, and locations will be added or removed according to
4743 * GDB now allows you to skip uninteresting functions and files when
4744 stepping with the "skip function" and "skip file" commands.
4746 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
4747 and "show remote hardware-watchpoint-length-limit". These allows to
4748 set or show the maximum length limit (in bytes) of a remote
4749 target hardware watchpoint.
4751 This allows e.g. to use "unlimited" hardware watchpoints with the
4752 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
4753 watchpoints are slower than real hardware watchpoints but are
4754 significantly faster than gdb software watchpoints.
4758 ** The register_pretty_printer function in module gdb.printing now takes
4759 an optional `replace' argument. If True, the new printer replaces any
4762 ** The "maint set python print-stack on|off" command has been
4763 deprecated and will be deleted in GDB 7.5.
4764 A new command: "set python print-stack none|full|message" has
4765 replaced it. Additionally, the default for "print-stack" is
4766 now "message", which just prints the error message without
4769 ** A prompt substitution hook (prompt_hook) is now available to the
4772 ** A new Python module, gdb.prompt has been added to the GDB Python
4773 modules library. This module provides functionality for
4774 escape sequences in prompts (used by set/show
4775 extended-prompt). These escape sequences are replaced by their
4776 corresponding value.
4778 ** Python commands and convenience-functions located in
4779 'data-directory'/python/gdb/command and
4780 'data-directory'/python/gdb/function are now automatically loaded
4783 ** Blocks now provide four new attributes. global_block and
4784 static_block will return the global and static blocks
4785 respectively. is_static and is_global are boolean attributes
4786 that indicate if the block is one of those two types.
4788 ** Symbols now provide the "type" attribute, the type of the symbol.
4790 ** The "gdb.breakpoint" function has been deprecated in favor of
4793 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
4794 of a function. This class is based on the "finish" command
4795 available in the CLI.
4797 ** Type objects for struct and union types now allow access to
4798 the fields using standard Python dictionary (mapping) methods.
4799 For example, "some_type['myfield']" now works, as does
4800 "some_type.items()".
4802 ** A new event "gdb.new_objfile" has been added, triggered by loading a
4805 ** A new function, "deep_items" has been added to the gdb.types
4806 module in the GDB Python modules library. This function returns
4807 an iterator over the fields of a struct or union type. Unlike
4808 the standard Python "iteritems" method, it will recursively traverse
4809 any anonymous fields.
4813 ** "*stopped" events can report several new "reason"s, such as
4816 ** Breakpoint changes are now notified using new async records, like
4817 "=breakpoint-modified".
4819 ** New command -ada-task-info.
4821 * libthread-db-search-path now supports two special values: $sdir and $pdir.
4822 $sdir specifies the default system locations of shared libraries.
4823 $pdir specifies the directory where the libpthread used by the application
4826 GDB no longer looks in $sdir and $pdir after it has searched the directories
4827 mentioned in libthread-db-search-path. If you want to search those
4828 directories, they must be specified in libthread-db-search-path.
4829 The default value of libthread-db-search-path on GNU/Linux and Solaris
4830 systems is now "$sdir:$pdir".
4832 $pdir is not supported by gdbserver, it is currently ignored.
4833 $sdir is supported by gdbserver.
4835 * New configure option --with-iconv-bin.
4836 When using the internationalization support like the one in the GNU C
4837 library, GDB will invoke the "iconv" program to get a list of supported
4838 character sets. If this program lives in a non-standard location, one can
4839 use this option to specify where to find it.
4841 * When natively debugging programs on PowerPC BookE processors running
4842 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
4843 watchpoints, which specify a mask in addition to an address to watch.
4844 The mask specifies that some bits of an address (the bits which are
4845 reset in the mask) should be ignored when matching the address accessed
4846 by the inferior against the watchpoint address. See the "PowerPC Embedded"
4847 section in the user manual for more details.
4849 * The new option --once causes GDBserver to stop listening for connections once
4850 the first connection is made. The listening port used by GDBserver will
4851 become available after that.
4853 * New commands "info macros" and "alias" have been added.
4855 * New function parameters suffix @entry specifies value of function parameter
4856 at the time the function got called. Entry values are available only since
4862 "!" is now an alias of the "shell" command.
4863 Note that no space is needed between "!" and SHELL COMMAND.
4867 watch EXPRESSION mask MASK_VALUE
4868 The watch command now supports the mask argument which allows creation
4869 of masked watchpoints, if the current architecture supports this feature.
4871 info auto-load-scripts [REGEXP]
4872 This command was formerly named "maintenance print section-scripts".
4873 It is now generally useful and is no longer a maintenance-only command.
4875 info macro [-all] [--] MACRO
4876 The info macro command has new options `-all' and `--'. The first for
4877 printing all definitions of a macro. The second for explicitly specifying
4878 the end of arguments and the beginning of the macro name in case the macro
4879 name starts with a hyphen.
4881 collect[/s] EXPRESSIONS
4882 The tracepoint collect command now takes an optional modifier "/s"
4883 that directs it to dereference pointer-to-character types and
4884 collect the bytes of memory up to a zero byte. The behavior is
4885 similar to what you see when you use the regular print command on a
4886 string. An optional integer following the "/s" sets a bound on the
4887 number of bytes that will be collected.
4890 The trace start command now interprets any supplied arguments as a
4891 note to be recorded with the trace run, with an effect similar to
4892 setting the variable trace-notes.
4895 The trace stop command now interprets any arguments as a note to be
4896 mentioned along with the tstatus report that the trace was stopped
4897 with a command. The effect is similar to setting the variable
4900 * Tracepoints can now be enabled and disabled at any time after a trace
4901 experiment has been started using the standard "enable" and "disable"
4902 commands. It is now possible to start a trace experiment with no enabled
4903 tracepoints; GDB will display a warning, but will allow the experiment to
4904 begin, assuming that tracepoints will be enabled as needed while the trace
4907 * Fast tracepoints on 32-bit x86-architectures can now be placed at
4908 locations with 4-byte instructions, when they were previously
4909 limited to locations with instructions of 5 bytes or longer.
4913 set debug dwarf2-read
4914 show debug dwarf2-read
4915 Turns on or off display of debugging messages related to reading
4916 DWARF debug info. The default is off.
4918 set debug symtab-create
4919 show debug symtab-create
4920 Turns on or off display of debugging messages related to symbol table
4921 creation. The default is off.
4924 show extended-prompt
4925 Set the GDB prompt, and allow escape sequences to be inserted to
4926 display miscellaneous information (see 'help set extended-prompt'
4927 for the list of sequences). This prompt (and any information
4928 accessed through the escape sequences) is updated every time the
4929 prompt is displayed.
4931 set print entry-values (both|compact|default|if-needed|no|only|preferred)
4932 show print entry-values
4933 Set printing of frame argument values at function entry. In some cases
4934 GDB can determine the value of function argument which was passed by the
4935 function caller, even if the value was modified inside the called function.
4937 set debug entry-values
4938 show debug entry-values
4939 Control display of debugging info for determining frame argument values at
4940 function entry and virtual tail call frames.
4942 set basenames-may-differ
4943 show basenames-may-differ
4944 Set whether a source file may have multiple base names.
4945 (A "base name" is the name of a file with the directory part removed.
4946 Example: The base name of "/home/user/hello.c" is "hello.c".)
4947 If set, GDB will canonicalize file names (e.g., expand symlinks)
4948 before comparing them. Canonicalization is an expensive operation,
4949 but it allows the same file be known by more than one base name.
4950 If not set (the default), all source files are assumed to have just
4951 one base name, and gdb will do file name comparisons more efficiently.
4957 Set a user name and notes for the current and any future trace runs.
4958 This is useful for long-running and/or disconnected traces, to
4959 inform others (or yourself) as to who is running the trace, supply
4960 contact information, or otherwise explain what is going on.
4962 set trace-stop-notes
4963 show trace-stop-notes
4964 Set a note attached to the trace run, that is displayed when the
4965 trace has been stopped by a tstop command. This is useful for
4966 instance as an explanation, if you are stopping a trace run that was
4967 started by someone else.
4969 * New remote packets
4973 Dynamically enable a tracepoint in a started trace experiment.
4977 Dynamically disable a tracepoint in a started trace experiment.
4981 Set the user and notes of the trace run.
4985 Query the current status of a tracepoint.
4989 Query the minimum length of instruction at which a fast tracepoint may
4992 * Dcache size (number of lines) and line-size are now runtime-configurable
4993 via "set dcache line" and "set dcache line-size" commands.
4997 Texas Instruments TMS320C6x tic6x-*-*
5001 Renesas RL78 rl78-*-elf
5003 *** Changes in GDB 7.3.1
5005 * The build failure for NetBSD and OpenBSD targets have now been fixed.
5007 *** Changes in GDB 7.3
5009 * GDB has a new command: "thread find [REGEXP]".
5010 It finds the thread id whose name, target id, or thread extra info
5011 matches the given regular expression.
5013 * The "catch syscall" command now works on mips*-linux* targets.
5015 * The -data-disassemble MI command now supports modes 2 and 3 for
5016 dumping the instruction opcodes.
5018 * New command line options
5020 -data-directory DIR Specify DIR as the "data-directory".
5021 This is mostly for testing purposes.
5023 * The "maint set python auto-load on|off" command has been renamed to
5024 "set auto-load-scripts on|off".
5026 * GDB has a new command: "set directories".
5027 It is like the "dir" command except that it replaces the
5028 source path list instead of augmenting it.
5030 * GDB now understands thread names.
5032 On GNU/Linux, "info threads" will display the thread name as set by
5033 prctl or pthread_setname_np.
5035 There is also a new command, "thread name", which can be used to
5036 assign a name internally for GDB to display.
5039 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
5040 has been integrated into GDB.
5044 ** The function gdb.Write now accepts an optional keyword 'stream'.
5045 This keyword, when provided, will direct the output to either
5046 stdout, stderr, or GDB's logging output.
5048 ** Parameters can now be be sub-classed in Python, and in particular
5049 you may implement the get_set_doc and get_show_doc functions.
5050 This improves how Parameter set/show documentation is processed
5051 and allows for more dynamic content.
5053 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
5054 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
5055 have an is_valid method.
5057 ** Breakpoints can now be sub-classed in Python, and in particular
5058 you may implement a 'stop' function that is executed each time
5059 the inferior reaches that breakpoint.
5061 ** New function gdb.lookup_global_symbol looks up a global symbol.
5063 ** GDB values in Python are now callable if the value represents a
5064 function. For example, if 'some_value' represents a function that
5065 takes two integer parameters and returns a value, you can call
5066 that function like so:
5068 result = some_value (10,20)
5070 ** Module gdb.types has been added.
5071 It contains a collection of utilities for working with gdb.Types objects:
5072 get_basic_type, has_field, make_enum_dict.
5074 ** Module gdb.printing has been added.
5075 It contains utilities for writing and registering pretty-printers.
5076 New classes: PrettyPrinter, SubPrettyPrinter,
5077 RegexpCollectionPrettyPrinter.
5078 New function: register_pretty_printer.
5080 ** New commands "info pretty-printers", "enable pretty-printer" and
5081 "disable pretty-printer" have been added.
5083 ** gdb.parameter("directories") is now available.
5085 ** New function gdb.newest_frame returns the newest frame in the
5088 ** The gdb.InferiorThread class has a new "name" attribute. This
5089 holds the thread's name.
5091 ** Python Support for Inferior events.
5092 Python scripts can add observers to be notified of events
5093 occurring in the process being debugged.
5094 The following events are currently supported:
5095 - gdb.events.cont Continue event.
5096 - gdb.events.exited Inferior exited event.
5097 - gdb.events.stop Signal received, and Breakpoint hit events.
5101 ** GDB now puts template parameters in scope when debugging in an
5102 instantiation. For example, if you have:
5104 template<int X> int func (void) { return X; }
5106 then if you step into func<5>, "print X" will show "5". This
5107 feature requires proper debuginfo support from the compiler; it
5108 was added to GCC 4.5.
5110 ** The motion commands "next", "finish", "until", and "advance" now
5111 work better when exceptions are thrown. In particular, GDB will
5112 no longer lose control of the inferior; instead, the GDB will
5113 stop the inferior at the point at which the exception is caught.
5114 This functionality requires a change in the exception handling
5115 code that was introduced in GCC 4.5.
5117 * GDB now follows GCC's rules on accessing volatile objects when
5118 reading or writing target state during expression evaluation.
5119 One notable difference to prior behavior is that "print x = 0"
5120 no longer generates a read of x; the value of the assignment is
5121 now always taken directly from the value being assigned.
5123 * GDB now has some support for using labels in the program's source in
5124 linespecs. For instance, you can use "advance label" to continue
5125 execution to a label.
5127 * GDB now has support for reading and writing a new .gdb_index
5128 section. This section holds a fast index of DWARF debugging
5129 information and can be used to greatly speed up GDB startup and
5130 operation. See the documentation for `save gdb-index' for details.
5132 * The "watch" command now accepts an optional "-location" argument.
5133 When used, this causes GDB to watch the memory referred to by the
5134 expression. Such a watchpoint is never deleted due to it going out
5137 * GDB now supports thread debugging of core dumps on GNU/Linux.
5139 GDB now activates thread debugging using the libthread_db library
5140 when debugging GNU/Linux core dumps, similarly to when debugging
5141 live processes. As a result, when debugging a core dump file, GDB
5142 is now able to display pthread_t ids of threads. For example, "info
5143 threads" shows the same output as when debugging the process when it
5144 was live. In earlier releases, you'd see something like this:
5147 * 1 LWP 6780 main () at main.c:10
5149 While now you see this:
5152 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
5154 It is also now possible to inspect TLS variables when debugging core
5157 When debugging a core dump generated on a machine other than the one
5158 used to run GDB, you may need to point GDB at the correct
5159 libthread_db library with the "set libthread-db-search-path"
5160 command. See the user manual for more details on this command.
5162 * When natively debugging programs on PowerPC BookE processors running
5163 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
5164 which stop execution of the inferior whenever it executes an instruction
5165 at any address within the specified range. See the "PowerPC Embedded"
5166 section in the user manual for more details.
5168 * New features in the GDB remote stub, GDBserver
5170 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
5171 and i686 LynxOS (version 5.x).
5173 ** GDBserver is now supported on Blackfin Linux.
5175 * New native configurations
5177 ia64 HP-UX ia64-*-hpux*
5181 Analog Devices, Inc. Blackfin Processor bfin-*
5183 * Ada task switching is now supported on sparc-elf targets when
5184 debugging a program using the Ravenscar Profile. For more information,
5185 see the "Tasking Support when using the Ravenscar Profile" section
5186 in the GDB user manual.
5188 * Guile support was removed.
5190 * New features in the GNU simulator
5192 ** The --map-info flag lists all known core mappings.
5194 ** CFI flashes may be simulated via the "cfi" device.
5196 *** Changes in GDB 7.2
5198 * Shared library support for remote targets by default
5200 When GDB is configured for a generic, non-OS specific target, like
5201 for example, --target=arm-eabi or one of the many *-*-elf targets,
5202 GDB now queries remote stubs for loaded shared libraries using the
5203 `qXfer:libraries:read' packet. Previously, shared library support
5204 was always disabled for such configurations.
5208 ** Argument Dependent Lookup (ADL)
5210 In C++ ADL lookup directs function search to the namespaces of its
5211 arguments even if the namespace has not been imported.
5221 Here the compiler will search for `foo' in the namespace of 'b'
5222 and find A::foo. GDB now supports this. This construct is commonly
5223 used in the Standard Template Library for operators.
5225 ** Improved User Defined Operator Support
5227 In addition to member operators, GDB now supports lookup of operators
5228 defined in a namespace and imported with a `using' directive, operators
5229 defined in the global scope, operators imported implicitly from an
5230 anonymous namespace, and the ADL operators mentioned in the previous
5232 GDB now also supports proper overload resolution for all the previously
5233 mentioned flavors of operators.
5235 ** static const class members
5237 Printing of static const class members that are initialized in the
5238 class definition has been fixed.
5240 * Windows Thread Information Block access.
5242 On Windows targets, GDB now supports displaying the Windows Thread
5243 Information Block (TIB) structure. This structure is visible either
5244 by using the new command `info w32 thread-information-block' or, by
5245 dereferencing the new convenience variable named `$_tlb', a
5246 thread-specific pointer to the TIB. This feature is also supported
5247 when remote debugging using GDBserver.
5249 * Static tracepoints
5251 Static tracepoints are calls in the user program into a tracing
5252 library. One such library is a port of the LTTng kernel tracer to
5253 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
5254 When debugging with GDBserver, GDB now supports combining the GDB
5255 tracepoint machinery with such libraries. For example: the user can
5256 use GDB to probe a static tracepoint marker (a call from the user
5257 program into the tracing library) with the new "strace" command (see
5258 "New commands" below). This creates a "static tracepoint" in the
5259 breakpoint list, that can be manipulated with the same feature set
5260 as fast and regular tracepoints. E.g., collect registers, local and
5261 global variables, collect trace state variables, and define
5262 tracepoint conditions. In addition, the user can collect extra
5263 static tracepoint marker specific data, by collecting the new
5264 $_sdata internal variable. When analyzing the trace buffer, you can
5265 inspect $_sdata like any other variable available to GDB. For more
5266 information, see the "Tracepoints" chapter in GDB user manual. New
5267 remote packets have been defined to support static tracepoints, see
5268 the "New remote packets" section below.
5270 * Better reconstruction of tracepoints after disconnected tracing
5272 GDB will attempt to download the original source form of tracepoint
5273 definitions when starting a trace run, and then will upload these
5274 upon reconnection to the target, resulting in a more accurate
5275 reconstruction of the tracepoints that are in use on the target.
5279 You can now exercise direct control over the ways that GDB can
5280 affect your program. For instance, you can disallow the setting of
5281 breakpoints, so that the program can run continuously (assuming
5282 non-stop mode). In addition, the "observer" variable is available
5283 to switch all of the different controls; in observer mode, GDB
5284 cannot affect the target's behavior at all, which is useful for
5285 tasks like diagnosing live systems in the field.
5287 * The new convenience variable $_thread holds the number of the
5290 * New remote packets
5294 Return the address of the Windows Thread Information Block of a given thread.
5298 In response to several of the tracepoint packets, the target may now
5299 also respond with a number of intermediate `qRelocInsn' request
5300 packets before the final result packet, to have GDB handle
5301 relocating an instruction to execute at a different address. This
5302 is particularly useful for stubs that support fast tracepoints. GDB
5303 reports support for this feature in the qSupported packet.
5307 List static tracepoint markers in the target program.
5311 List static tracepoint markers at a given address in the target
5314 qXfer:statictrace:read
5316 Read the static trace data collected (by a `collect $_sdata'
5317 tracepoint action). The remote stub reports support for this packet
5318 to gdb's qSupported query.
5322 Send the current settings of GDB's permission flags.
5326 Send part of the source (textual) form of a tracepoint definition,
5327 which includes location, conditional, and action list.
5329 * The source command now accepts a -s option to force searching for the
5330 script in the source search path even if the script name specifies
5333 * New features in the GDB remote stub, GDBserver
5335 - GDBserver now support tracepoints (including fast tracepoints, and
5336 static tracepoints). The feature is currently supported by the
5337 i386-linux and amd64-linux builds. See the "Tracepoints support
5338 in gdbserver" section in the manual for more information.
5340 GDBserver JIT compiles the tracepoint's conditional agent
5341 expression bytecode into native code whenever possible for low
5342 overhead dynamic tracepoints conditionals. For such tracepoints,
5343 an expression that examines program state is evaluated when the
5344 tracepoint is reached, in order to determine whether to capture
5345 trace data. If the condition is simple and false, processing the
5346 tracepoint finishes very quickly and no data is gathered.
5348 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
5349 for static tracepoints support.
5351 - GDBserver now supports x86_64 Windows 64-bit debugging.
5353 * GDB now sends xmlRegisters= in qSupported packet to indicate that
5354 it understands register description.
5356 * The --batch flag now disables pagination and queries.
5358 * X86 general purpose registers
5360 GDB now supports reading/writing byte, word and double-word x86
5361 general purpose registers directly. This means you can use, say,
5362 $ah or $ax to refer, respectively, to the byte register AH and
5363 16-bit word register AX that are actually portions of the 32-bit
5364 register EAX or 64-bit register RAX.
5366 * The `commands' command now accepts a range of breakpoints to modify.
5367 A plain `commands' following a command that creates multiple
5368 breakpoints affects all the breakpoints set by that command. This
5369 applies to breakpoints set by `rbreak', and also applies when a
5370 single `break' command creates multiple breakpoints (e.g.,
5371 breakpoints on overloaded c++ functions).
5373 * The `rbreak' command now accepts a filename specification as part of
5374 its argument, limiting the functions selected by the regex to those
5375 in the specified file.
5377 * Support for remote debugging Windows and SymbianOS shared libraries
5378 from Unix hosts has been improved. Non Windows GDB builds now can
5379 understand target reported file names that follow MS-DOS based file
5380 system semantics, such as file names that include drive letters and
5381 use the backslash character as directory separator. This makes it
5382 possible to transparently use the "set sysroot" and "set
5383 solib-search-path" on Unix hosts to point as host copies of the
5384 target's shared libraries. See the new command "set
5385 target-file-system-kind" described below, and the "Commands to
5386 specify files" section in the user manual for more information.
5390 eval template, expressions...
5391 Convert the values of one or more expressions under the control
5392 of the string template to a command line, and call it.
5394 set target-file-system-kind unix|dos-based|auto
5395 show target-file-system-kind
5396 Set or show the assumed file system kind for target reported file
5399 save breakpoints <filename>
5400 Save all current breakpoint definitions to a file suitable for use
5401 in a later debugging session. To read the saved breakpoint
5402 definitions, use the `source' command.
5404 `save tracepoints' is a new alias for `save-tracepoints'. The latter
5407 info static-tracepoint-markers
5408 Display information about static tracepoint markers in the target.
5410 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
5411 Define a static tracepoint by probing a marker at the given
5412 function, line, address, or marker ID.
5416 Enable and disable observer mode.
5418 set may-write-registers on|off
5419 set may-write-memory on|off
5420 set may-insert-breakpoints on|off
5421 set may-insert-tracepoints on|off
5422 set may-insert-fast-tracepoints on|off
5423 set may-interrupt on|off
5424 Set individual permissions for GDB effects on the target. Note that
5425 some of these settings can have undesirable or surprising
5426 consequences, particularly when changed in the middle of a session.
5427 For instance, disabling the writing of memory can prevent
5428 breakpoints from being inserted, cause single-stepping to fail, or
5429 even crash your program, if you disable after breakpoints have been
5430 inserted. However, GDB should not crash.
5432 set record memory-query on|off
5433 show record memory-query
5434 Control whether to stop the inferior if memory changes caused
5435 by an instruction cannot be recorded.
5440 The disassemble command now supports "start,+length" form of two arguments.
5444 ** GDB now provides a new directory location, called the python directory,
5445 where Python scripts written for GDB can be installed. The location
5446 of that directory is <data-directory>/python, where <data-directory>
5447 is the GDB data directory. For more details, see section `Scripting
5448 GDB using Python' in the manual.
5450 ** The GDB Python API now has access to breakpoints, symbols, symbol
5451 tables, program spaces, inferiors, threads and frame's code blocks.
5452 Additionally, GDB Parameters can now be created from the API, and
5453 manipulated via set/show in the CLI.
5455 ** New functions gdb.target_charset, gdb.target_wide_charset,
5456 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
5458 ** New exception gdb.GdbError.
5460 ** Pretty-printers are now also looked up in the current program space.
5462 ** Pretty-printers can now be individually enabled and disabled.
5464 ** GDB now looks for names of Python scripts to auto-load in a
5465 special section named `.debug_gdb_scripts', in addition to looking
5466 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
5468 * Tracepoint actions were unified with breakpoint commands. In particular,
5469 there are no longer differences in "info break" output for breakpoints and
5470 tracepoints and the "commands" command can be used for both tracepoints and
5471 regular breakpoints.
5475 ARM Symbian arm*-*-symbianelf*
5477 * D language support.
5478 GDB now supports debugging programs written in the D programming
5481 * GDB now supports the extended ptrace interface for PowerPC which is
5482 available since Linux kernel version 2.6.34. This automatically enables
5483 any hardware breakpoints and additional hardware watchpoints available in
5484 the processor. The old ptrace interface exposes just one hardware
5485 watchpoint and no hardware breakpoints.
5487 * GDB is now able to use the Data Value Compare (DVC) register available on
5488 embedded PowerPC processors to implement in hardware simple watchpoint
5489 conditions of the form:
5491 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
5493 This works in native GDB running on Linux kernels with the extended ptrace
5494 interface mentioned above.
5496 *** Changes in GDB 7.1
5500 ** Namespace Support
5502 GDB now supports importing of namespaces in C++. This enables the
5503 user to inspect variables from imported namespaces. Support for
5504 namepace aliasing has also been added. So, if a namespace is
5505 aliased in the current scope (e.g. namepace C=A; ) the user can
5506 print variables using the alias (e.g. (gdb) print C::x).
5510 All known bugs relating to the printing of virtual base class were
5511 fixed. It is now possible to call overloaded static methods using a
5516 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
5517 and reinterpret_cast<> are now handled by the C++ expression parser.
5521 Xilinx MicroBlaze microblaze-*-*
5526 Xilinx MicroBlaze microblaze
5529 * Multi-program debugging.
5531 GDB now has support for multi-program (a.k.a. multi-executable or
5532 multi-exec) debugging. This allows for debugging multiple inferiors
5533 simultaneously each running a different program under the same GDB
5534 session. See "Debugging Multiple Inferiors and Programs" in the
5535 manual for more information. This implied some user visible changes
5536 in the multi-inferior support. For example, "info inferiors" now
5537 lists inferiors that are not running yet or that have exited
5538 already. See also "New commands" and "New options" below.
5540 * New tracing features
5542 GDB's tracepoint facility now includes several new features:
5544 ** Trace state variables
5546 GDB tracepoints now include support for trace state variables, which
5547 are variables managed by the target agent during a tracing
5548 experiment. They are useful for tracepoints that trigger each
5549 other, so for instance one tracepoint can count hits in a variable,
5550 and then a second tracepoint has a condition that is true when the
5551 count reaches a particular value. Trace state variables share the
5552 $-syntax of GDB convenience variables, and can appear in both
5553 tracepoint actions and condition expressions. Use the "tvariable"
5554 command to create, and "info tvariables" to view; see "Trace State
5555 Variables" in the manual for more detail.
5559 GDB now includes an option for defining fast tracepoints, which
5560 targets may implement more efficiently, such as by installing a jump
5561 into the target agent rather than a trap instruction. The resulting
5562 speedup can be by two orders of magnitude or more, although the
5563 tradeoff is that some program locations on some target architectures
5564 might not allow fast tracepoint installation, for instance if the
5565 instruction to be replaced is shorter than the jump. To request a
5566 fast tracepoint, use the "ftrace" command, with syntax identical to
5567 the regular trace command.
5569 ** Disconnected tracing
5571 It is now possible to detach GDB from the target while it is running
5572 a trace experiment, then reconnect later to see how the experiment
5573 is going. In addition, a new variable disconnected-tracing lets you
5574 tell the target agent whether to continue running a trace if the
5575 connection is lost unexpectedly.
5579 GDB now has the ability to save the trace buffer into a file, and
5580 then use that file as a target, similarly to you can do with
5581 corefiles. You can select trace frames, print data that was
5582 collected in them, and use tstatus to display the state of the
5583 tracing run at the moment that it was saved. To create a trace
5584 file, use "tsave <filename>", and to use it, do "target tfile
5587 ** Circular trace buffer
5589 You can ask the target agent to handle the trace buffer as a
5590 circular buffer, discarding the oldest trace frames to make room for
5591 newer ones, by setting circular-trace-buffer to on. This feature may
5592 not be available for all target agents.
5597 The disassemble command, when invoked with two arguments, now requires
5598 the arguments to be comma-separated.
5601 The info variables command now displays variable definitions. Files
5602 which only declare a variable are not shown.
5605 The source command is now capable of sourcing Python scripts.
5606 This feature is dependent on the debugger being build with Python
5609 Related to this enhancement is also the introduction of a new command
5610 "set script-extension" (see below).
5612 * New commands (for set/show, see "New options" below)
5614 record save [<FILENAME>]
5615 Save a file (in core file format) containing the process record
5616 execution log for replay debugging at a later time.
5618 record restore <FILENAME>
5619 Restore the process record execution log that was saved at an
5620 earlier time, for replay debugging.
5622 add-inferior [-copies <N>] [-exec <FILENAME>]
5625 clone-inferior [-copies <N>] [ID]
5626 Make a new inferior ready to execute the same program another
5627 inferior has loaded.
5632 maint info program-spaces
5633 List the program spaces loaded into GDB.
5635 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
5636 show remote interrupt-sequence
5637 Allow the user to select one of ^C, a BREAK signal or BREAK-g
5638 as the sequence to the remote target in order to interrupt the execution.
5639 Ctrl-C is a default. Some system prefers BREAK which is high level of
5640 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
5641 Magic SysRq g. It is BREAK signal and character 'g'.
5643 set remote interrupt-on-connect [on | off]
5644 show remote interrupt-on-connect
5645 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
5646 remote target when gdb connects to it. This is needed when you debug
5649 set remotebreak [on | off]
5651 Deprecated. Use "set/show remote interrupt-sequence" instead.
5653 tvariable $NAME [ = EXP ]
5654 Create or modify a trace state variable.
5657 List trace state variables and their values.
5659 delete tvariable $NAME ...
5660 Delete one or more trace state variables.
5663 Evaluate the given expressions without collecting anything into the
5664 trace buffer. (Valid in tracepoint actions only.)
5666 ftrace FN / FILE:LINE / *ADDR
5667 Define a fast tracepoint at the given function, line, or address.
5669 * New expression syntax
5671 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
5672 GDB now parses 0b101010 identically with 42.
5676 set follow-exec-mode new|same
5677 show follow-exec-mode
5678 Control whether GDB reuses the same inferior across an exec call or
5679 creates a new one. This is useful to be able to restart the old
5680 executable after the inferior having done an exec call.
5682 set default-collect EXPR, ...
5683 show default-collect
5684 Define a list of expressions to be collected at each tracepoint.
5685 This is a useful way to ensure essential items are not overlooked,
5686 such as registers or a critical global variable.
5688 set disconnected-tracing
5689 show disconnected-tracing
5690 If set to 1, the target is instructed to continue tracing if it
5691 loses its connection to GDB. If 0, the target is to stop tracing
5694 set circular-trace-buffer
5695 show circular-trace-buffer
5696 If set to on, the target is instructed to use a circular trace buffer
5697 and discard the oldest trace frames instead of stopping the trace due
5698 to a full trace buffer. If set to off, the trace stops when the buffer
5699 fills up. Some targets may not support this.
5701 set script-extension off|soft|strict
5702 show script-extension
5703 If set to "off", the debugger does not perform any script language
5704 recognition, and all sourced files are assumed to be GDB scripts.
5705 If set to "soft" (the default), files are sourced according to
5706 filename extension, falling back to GDB scripts if the first
5708 If set to "strict", files are sourced according to filename extension.
5710 set ada trust-PAD-over-XVS on|off
5711 show ada trust-PAD-over-XVS
5712 If off, activate a workaround against a bug in the debugging information
5713 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
5714 the GCC sources for more information about the GNAT encoding and
5715 PAD types in particular). It is always safe to set this option to
5716 off, but this introduces a slight performance penalty. The default
5719 * Python API Improvements
5721 ** GDB provides the new class gdb.LazyString. This is useful in
5722 some pretty-printing cases. The new method gdb.Value.lazy_string
5723 provides a simple way to create objects of this type.
5725 ** The fields returned by gdb.Type.fields now have an
5726 `is_base_class' attribute.
5728 ** The new method gdb.Type.range returns the range of an array type.
5730 ** The new method gdb.parse_and_eval can be used to parse and
5731 evaluate an expression.
5733 * New remote packets
5736 Define a trace state variable.
5739 Get the current value of a trace state variable.
5742 Set desired tracing behavior upon disconnection.
5745 Set the trace buffer to be linear or circular.
5748 Get data about the tracepoints currently in use.
5752 Process record now works correctly with hardware watchpoints.
5754 Multiple bug fixes have been made to the mips-irix port, making it
5755 much more reliable. In particular:
5756 - Debugging threaded applications is now possible again. Previously,
5757 GDB would hang while starting the program, or while waiting for
5758 the program to stop at a breakpoint.
5759 - Attaching to a running process no longer hangs.
5760 - An error occurring while loading a core file has been fixed.
5761 - Changing the value of the PC register now works again. This fixes
5762 problems observed when using the "jump" command, or when calling
5763 a function from GDB, or even when assigning a new value to $pc.
5764 - With the "finish" and "return" commands, the return value for functions
5765 returning a small array is now correctly printed.
5766 - It is now possible to break on shared library code which gets executed
5767 during a shared library init phase (code executed while executing
5768 their .init section). Previously, the breakpoint would have no effect.
5769 - GDB is now able to backtrace through the signal handler for
5770 non-threaded programs.
5772 PIE (Position Independent Executable) programs debugging is now supported.
5773 This includes debugging execution of PIC (Position Independent Code) shared
5774 libraries although for that, it should be possible to run such libraries as an
5777 *** Changes in GDB 7.0
5779 * GDB now has an interface for JIT compilation. Applications that
5780 dynamically generate code can create symbol files in memory and register
5781 them with GDB. For users, the feature should work transparently, and
5782 for JIT developers, the interface is documented in the GDB manual in the
5783 "JIT Compilation Interface" chapter.
5785 * Tracepoints may now be conditional. The syntax is as for
5786 breakpoints; either an "if" clause appended to the "trace" command,
5787 or the "condition" command is available. GDB sends the condition to
5788 the target for evaluation using the same bytecode format as is used
5789 for tracepoint actions.
5791 * The disassemble command now supports: an optional /r modifier, print the
5792 raw instructions in hex as well as in symbolic form, and an optional /m
5793 modifier to print mixed source+assembly.
5795 * Process record and replay
5797 In a architecture environment that supports ``process record and
5798 replay'', ``process record and replay'' target can record a log of
5799 the process execution, and replay it with both forward and reverse
5802 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
5803 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
5804 set execution-direction {forward|reverse}, for targets that support
5807 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
5808 feature is available with a native GDB running on kernel version
5811 * GDB now has support for multi-byte and wide character sets on the
5812 target. Strings whose character type is wchar_t, char16_t, or
5813 char32_t are now correctly printed. GDB supports wide- and unicode-
5814 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
5815 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
5816 `printf'. This feature requires iconv to work properly; if your
5817 system does not have a working iconv, GDB can use GNU libiconv. See
5818 the installation instructions for more information.
5820 * GDB now supports automatic retrieval of shared library files from
5821 remote targets. To use this feature, specify a system root that begins
5822 with the `remote:' prefix, either via the `set sysroot' command or via
5823 the `--with-sysroot' configure-time option.
5825 * "info sharedlibrary" now takes an optional regex of libraries to show,
5826 and it now reports if a shared library has no debugging information.
5828 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
5829 now complete on file names.
5831 * When completing in expressions, gdb will attempt to limit
5832 completions to allowable structure or union fields, where appropriate.
5833 For instance, consider:
5835 # struct example { int f1; double f2; };
5836 # struct example variable;
5839 If the user types TAB at the end of this command line, the available
5840 completions will be "f1" and "f2".
5842 * Inlined functions are now supported. They show up in backtraces, and
5843 the "step", "next", and "finish" commands handle them automatically.
5845 * GDB now supports the token-splicing (##) and stringification (#)
5846 operators when expanding macros. It also supports variable-arity
5849 * GDB now supports inspecting extra signal information, exported by
5850 the new $_siginfo convenience variable. The feature is currently
5851 implemented on linux ARM, i386 and amd64.
5853 * GDB can now display the VFP floating point registers and NEON vector
5854 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
5855 can provide these registers (requires Linux 2.6.30 or later). Remote
5856 and simulator targets may also provide them.
5858 * New remote packets
5861 Search memory for a sequence of bytes.
5864 Turn off `+'/`-' protocol acknowledgments to permit more efficient
5865 operation over reliable transport links. Use of this packet is
5866 controlled by the `set remote noack-packet' command.
5869 Kill the process with the specified process ID. Use this in preference
5870 to `k' when multiprocess protocol extensions are supported.
5873 Obtains additional operating system information
5877 Read or write additional signal information.
5879 * Removed remote protocol undocumented extension
5881 An undocumented extension to the remote protocol's `S' stop reply
5882 packet that permitted the stub to pass a process id was removed.
5883 Remote servers should use the `T' stop reply packet instead.
5885 * GDB now supports multiple function calling conventions according to the
5886 DWARF-2 DW_AT_calling_convention function attribute.
5888 * The SH target utilizes the aforementioned change to distinguish between gcc
5889 and Renesas calling convention. It also adds the new CLI commands
5890 `set/show sh calling-convention'.
5892 * GDB can now read compressed debug sections, as produced by GNU gold
5893 with the --compress-debug-sections=zlib flag.
5895 * 64-bit core files are now supported on AIX.
5897 * Thread switching is now supported on Tru64.
5899 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
5900 which will be allocated using malloc later in program execution.
5902 * The qXfer:libraries:read remote protocol packet now allows passing a
5903 list of section offsets.
5905 * On GNU/Linux, GDB can now attach to stopped processes. Several race
5906 conditions handling signals delivered during attach or thread creation
5907 have also been fixed.
5909 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
5910 From the user's standpoint, all unqualified instances of True and False
5911 are treated as the standard definitions, regardless of context.
5913 * GDB now parses C++ symbol and type names more flexibly. For
5916 template<typename T> class C { };
5919 GDB will now correctly handle all of:
5921 ptype C<char const *>
5922 ptype C<char const*>
5923 ptype C<const char *>
5924 ptype C<const char*>
5926 * New features in the GDB remote stub, gdbserver
5928 - The "--wrapper" command-line argument tells gdbserver to use a
5929 wrapper program to launch programs for debugging.
5931 - On PowerPC and S/390 targets, it is now possible to use a single
5932 gdbserver executable to debug both 32-bit and 64-bit programs.
5933 (This requires gdbserver itself to be built as a 64-bit executable.)
5935 - gdbserver uses the new noack protocol mode for TCP connections to
5936 reduce communications latency, if also supported and enabled in GDB.
5938 - Support for the sparc64-linux-gnu target is now included in
5941 - The amd64-linux build of gdbserver now supports debugging both
5942 32-bit and 64-bit programs.
5944 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
5945 now support hardware watchpoints, and will use them automatically
5950 GDB now has support for scripting using Python. Whether this is
5951 available is determined at configure time.
5953 New GDB commands can now be written in Python.
5955 * Ada tasking support
5957 Ada tasks can now be inspected in GDB. The following commands have
5961 Print the list of Ada tasks.
5963 Print detailed information about task number N.
5965 Print the task number of the current task.
5967 Switch the context of debugging to task number N.
5969 * Support for user-defined prefixed commands. The "define" command can
5970 add new commands to existing prefixes, e.g. "target".
5972 * Multi-inferior, multi-process debugging.
5974 GDB now has generalized support for multi-inferior debugging. See
5975 "Debugging Multiple Inferiors" in the manual for more information.
5976 Although availability still depends on target support, the command
5977 set is more uniform now. The GNU/Linux specific multi-forks support
5978 has been migrated to this new framework. This implied some user
5979 visible changes; see "New commands" and also "Removed commands"
5982 * Target descriptions can now describe the target OS ABI. See the
5983 "Target Description Format" section in the user manual for more
5986 * Target descriptions can now describe "compatible" architectures
5987 to indicate that the target can execute applications for a different
5988 architecture in addition to those for the main target architecture.
5989 See the "Target Description Format" section in the user manual for
5992 * Multi-architecture debugging.
5994 GDB now includes general supports for debugging applications on
5995 hybrid systems that use more than one single processor architecture
5996 at the same time. Each such hybrid architecture still requires
5997 specific support to be added. The only hybrid architecture supported
5998 in this version of GDB is the Cell Broadband Engine.
6000 * GDB now supports integrated debugging of Cell/B.E. applications that
6001 use both the PPU and SPU architectures. To enable support for hybrid
6002 Cell/B.E. debugging, you need to configure GDB to support both the
6003 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
6004 --enable-targets configure option.
6006 * Non-stop mode debugging.
6008 For some targets, GDB now supports an optional mode of operation in
6009 which you can examine stopped threads while other threads continue
6010 to execute freely. This is referred to as non-stop mode, with the
6011 old mode referred to as all-stop mode. See the "Non-Stop Mode"
6012 section in the user manual for more information.
6014 To be able to support remote non-stop debugging, a remote stub needs
6015 to implement the non-stop mode remote protocol extensions, as
6016 described in the "Remote Non-Stop" section of the user manual. The
6017 GDB remote stub, gdbserver, has been adjusted to support these
6018 extensions on linux targets.
6020 * New commands (for set/show, see "New options" below)
6022 catch syscall [NAME(S) | NUMBER(S)]
6023 Catch system calls. Arguments, which should be names of system
6024 calls or their numbers, mean catch only those syscalls. Without
6025 arguments, every syscall will be caught. When the inferior issues
6026 any of the specified syscalls, GDB will stop and announce the system
6027 call, both when it is called and when its call returns. This
6028 feature is currently available with a native GDB running on the
6029 Linux Kernel, under the following architectures: x86, x86_64,
6030 PowerPC and PowerPC64.
6032 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
6034 Search memory for a sequence of bytes.
6036 maint set python print-stack
6037 maint show python print-stack
6038 Show a stack trace when an error is encountered in a Python script.
6041 Invoke CODE by passing it to the Python interpreter.
6046 These allow macros to be defined, undefined, and listed
6050 Show operating system information about processes.
6053 List the inferiors currently under GDB's control.
6056 Switch focus to inferior number NUM.
6059 Detach from inferior number NUM.
6062 Kill inferior number NUM.
6066 set spu stop-on-load
6067 show spu stop-on-load
6068 Control whether to stop for new SPE threads during Cell/B.E. debugging.
6070 set spu auto-flush-cache
6071 show spu auto-flush-cache
6072 Control whether to automatically flush the software-managed cache
6073 during Cell/B.E. debugging.
6075 set sh calling-convention
6076 show sh calling-convention
6077 Control the calling convention used when calling SH target functions.
6080 show debug timestamp
6081 Control display of timestamps with GDB debugging output.
6083 set disassemble-next-line
6084 show disassemble-next-line
6085 Control display of disassembled source lines or instructions when
6088 set remote noack-packet
6089 show remote noack-packet
6090 Set/show the use of remote protocol QStartNoAckMode packet. See above
6091 under "New remote packets."
6093 set remote query-attached-packet
6094 show remote query-attached-packet
6095 Control use of remote protocol `qAttached' (query-attached) packet.
6097 set remote read-siginfo-object
6098 show remote read-siginfo-object
6099 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
6102 set remote write-siginfo-object
6103 show remote write-siginfo-object
6104 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
6107 set remote reverse-continue
6108 show remote reverse-continue
6109 Control use of remote protocol 'bc' (reverse-continue) packet.
6111 set remote reverse-step
6112 show remote reverse-step
6113 Control use of remote protocol 'bs' (reverse-step) packet.
6115 set displaced-stepping
6116 show displaced-stepping
6117 Control displaced stepping mode. Displaced stepping is a way to
6118 single-step over breakpoints without removing them from the debuggee.
6119 Also known as "out-of-line single-stepping".
6122 show debug displaced
6123 Control display of debugging info for displaced stepping.
6125 maint set internal-error
6126 maint show internal-error
6127 Control what GDB does when an internal error is detected.
6129 maint set internal-warning
6130 maint show internal-warning
6131 Control what GDB does when an internal warning is detected.
6136 Use a wrapper program to launch programs for debugging.
6138 set multiple-symbols (all|ask|cancel)
6139 show multiple-symbols
6140 The value of this variable can be changed to adjust the debugger behavior
6141 when an expression or a breakpoint location contains an ambiguous symbol
6142 name (an overloaded function name, for instance).
6144 set breakpoint always-inserted
6145 show breakpoint always-inserted
6146 Keep breakpoints always inserted in the target, as opposed to inserting
6147 them when resuming the target, and removing them when the target stops.
6148 This option can improve debugger performance on slow remote targets.
6150 set arm fallback-mode (arm|thumb|auto)
6151 show arm fallback-mode
6152 set arm force-mode (arm|thumb|auto)
6154 These commands control how ARM GDB determines whether instructions
6155 are ARM or Thumb. The default for both settings is auto, which uses
6156 the current CPSR value for instructions without symbols; previous
6157 versions of GDB behaved as if "set arm fallback-mode arm".
6159 set arm unwind-secure-frames
6160 Enable unwinding from Non-secure to Secure mode on Cortex-M with
6162 This can trigger security exceptions when unwinding exception stacks.
6164 set disable-randomization
6165 show disable-randomization
6166 Standalone programs run with the virtual address space randomization enabled
6167 by default on some platforms. This option keeps the addresses stable across
6168 multiple debugging sessions.
6172 Control whether other threads are stopped or not when some thread hits
6177 Requests that asynchronous execution is enabled in the target, if available.
6178 In this case, it's possible to resume target in the background, and interact
6179 with GDB while the target is running. "show target-async" displays the
6180 current state of asynchronous execution of the target.
6182 set target-wide-charset
6183 show target-wide-charset
6184 The target-wide-charset is the name of the character set that GDB
6185 uses when printing characters whose type is wchar_t.
6187 set tcp auto-retry (on|off)
6189 set tcp connect-timeout
6190 show tcp connect-timeout
6191 These commands allow GDB to retry failed TCP connections to a remote stub
6192 with a specified timeout period; this is useful if the stub is launched
6193 in parallel with GDB but may not be ready to accept connections immediately.
6195 set libthread-db-search-path
6196 show libthread-db-search-path
6197 Control list of directories which GDB will search for appropriate
6200 set schedule-multiple (on|off)
6201 show schedule-multiple
6202 Allow GDB to resume all threads of all processes or only threads of
6203 the current process.
6207 Use more aggressive caching for accesses to the stack. This improves
6208 performance of remote debugging (particularly backtraces) without
6209 affecting correctness.
6211 set interactive-mode (on|off|auto)
6212 show interactive-mode
6213 Control whether GDB runs in interactive mode (on) or not (off).
6214 When in interactive mode, GDB waits for the user to answer all
6215 queries. Otherwise, GDB does not wait and assumes the default
6216 answer. When set to auto (the default), GDB determines which
6217 mode to use based on the stdin settings.
6222 For program forks, this is replaced by the new more generic `info
6223 inferiors' command. To list checkpoints, you can still use the
6224 `info checkpoints' command, which was an alias for the `info forks'
6228 Replaced by the new `inferior' command. To switch between
6229 checkpoints, you can still use the `restart' command, which was an
6230 alias for the `fork' command.
6233 This is removed, since some targets don't have a notion of
6234 processes. To switch between processes, you can still use the
6235 `inferior' command using GDB's own inferior number.
6238 For program forks, this is replaced by the new more generic `kill
6239 inferior' command. To delete a checkpoint, you can still use the
6240 `delete checkpoint' command, which was an alias for the `delete
6244 For program forks, this is replaced by the new more generic `detach
6245 inferior' command. To detach a checkpoint, you can still use the
6246 `detach checkpoint' command, which was an alias for the `detach
6249 * New native configurations
6251 x86/x86_64 Darwin i[34567]86-*-darwin*
6253 x86_64 MinGW x86_64-*-mingw*
6257 Lattice Mico32 lm32-*
6258 x86 DICOS i[34567]86-*-dicos*
6259 x86_64 DICOS x86_64-*-dicos*
6262 * The GDB remote stub, gdbserver, now supports x86 Windows CE
6263 (mingw32ce) debugging.
6269 These commands were actually not implemented on any target.
6271 *** Changes in GDB 6.8
6273 * New native configurations
6275 NetBSD/hppa hppa*-*netbsd*
6276 Xtensa GNU/Linux xtensa*-*-linux*
6280 NetBSD/hppa hppa*-*-netbsd*
6281 Xtensa GNU/Linux xtensa*-*-linux*
6283 * Change in command line behavior -- corefiles vs. process ids.
6285 When the '-p NUMBER' or '--pid NUMBER' options are used, and
6286 attaching to process NUMBER fails, GDB no longer attempts to open a
6287 core file named NUMBER. Attaching to a program using the -c option
6288 is no longer supported. Instead, use the '-p' or '--pid' options.
6290 * GDB can now be built as a native debugger for debugging Windows x86
6291 (mingw32) Portable Executable (PE) programs.
6293 * Pending breakpoints no longer change their number when their address
6296 * GDB now supports breakpoints with multiple locations,
6297 including breakpoints on C++ constructors, inside C++ templates,
6298 and in inlined functions.
6300 * GDB's ability to debug optimized code has been improved. GDB more
6301 accurately identifies function bodies and lexical blocks that occupy
6302 more than one contiguous range of addresses.
6304 * Target descriptions can now describe registers for PowerPC.
6306 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
6307 registers on PowerPC targets.
6309 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
6310 targets even when the libthread_db library is not available.
6312 * The GDB remote stub, gdbserver, now supports the new file transfer
6313 commands (remote put, remote get, and remote delete).
6315 * The GDB remote stub, gdbserver, now supports run and attach in
6316 extended-remote mode.
6318 * hppa*64*-*-hpux11* target broken
6319 The debugger is unable to start a program and fails with the following
6320 error: "Error trying to get information about dynamic linker".
6321 The gdb-6.7 release is also affected.
6323 * GDB now supports the --enable-targets= configure option to allow
6324 building a single GDB executable that supports multiple remote
6325 target architectures.
6327 * GDB now supports debugging C and C++ programs which use the
6328 Decimal Floating Point extension. In addition, the PowerPC target
6329 now has a set of pseudo-registers to inspect decimal float values
6330 stored in two consecutive float registers.
6332 * The -break-insert MI command can optionally create pending
6335 * Improved support for debugging Ada
6336 Many improvements to the Ada language support have been made. These
6338 - Better support for Ada2005 interface types
6339 - Improved handling of arrays and slices in general
6340 - Better support for Taft-amendment types
6341 - The '{type} ADDRESS' expression is now allowed on the left hand-side
6343 - Improved command completion in Ada
6346 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
6351 set print frame-arguments (all|scalars|none)
6352 show print frame-arguments
6353 The value of this variable can be changed to control which argument
6354 values should be printed by the debugger when displaying a frame.
6359 Transfer files to and from a remote target, and delete remote files.
6366 Transfer files to and from a remote target, and delete remote files.
6368 * New remote packets
6375 Open, close, read, write, and delete files on the remote system.
6378 Attach to an existing process on the remote system, in extended-remote
6382 Run a new process on the remote system, in extended-remote mode.
6384 *** Changes in GDB 6.7
6386 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
6387 bfd, libiberty and opcodes, as revealed by static analysis donated by
6388 Coverity, Inc. (http://scan.coverity.com).
6390 * When looking up multiply-defined global symbols, GDB will now prefer the
6391 symbol definition in the current shared library if it was built using the
6392 -Bsymbolic linker option.
6394 * When the Text User Interface (TUI) is not configured, GDB will now
6395 recognize the -tui command-line option and print a message that the TUI
6398 * The GDB remote stub, gdbserver, now has lower overhead for high
6399 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
6401 * GDB for MIPS targets now autodetects whether a remote target provides
6402 32-bit or 64-bit register values.
6404 * Support for C++ member pointers has been improved.
6406 * GDB now understands XML target descriptions, which specify the
6407 target's overall architecture. GDB can read a description from
6408 a local file or over the remote serial protocol.
6410 * Vectors of single-byte data use a new integer type which is not
6411 automatically displayed as character or string data.
6413 * The /s format now works with the print command. It displays
6414 arrays of single-byte integers and pointers to single-byte integers
6417 * Target descriptions can now describe target-specific registers,
6418 for architectures which have implemented the support (currently
6419 only ARM, M68K, and MIPS).
6421 * GDB and the GDB remote stub, gdbserver, now support the XScale
6424 * The GDB remote stub, gdbserver, has been updated to support
6425 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
6426 has been rewritten to use the standard GDB remote protocol.
6428 * GDB can now step into C++ functions which are called through thunks.
6430 * GDB for the Cell/B.E. SPU now supports overlay debugging.
6432 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
6433 layout. It also supports a TextSeg= and DataSeg= response when only
6434 segment base addresses (rather than offsets) are available.
6436 * The /i format now outputs any trailing branch delay slot instructions
6437 immediately following the last instruction within the count specified.
6439 * The GDB remote protocol "T" stop reply packet now supports a
6440 "library" response. Combined with the new "qXfer:libraries:read"
6441 packet, this response allows GDB to debug shared libraries on targets
6442 where the operating system manages the list of loaded libraries (e.g.
6443 Windows and SymbianOS).
6445 * The GDB remote stub, gdbserver, now supports dynamic link libraries
6446 (DLLs) on Windows and Windows CE targets.
6448 * GDB now supports a faster verification that a .debug file matches its binary
6449 according to its build-id signature, if the signature is present.
6455 Enable or disable hardware flow control (RTS/CTS) on the serial port
6456 when debugging using remote targets.
6458 set mem inaccessible-by-default
6459 show mem inaccessible-by-default
6460 If the target supplies a memory map, for instance via the remote
6461 protocol's "qXfer:memory-map:read" packet, setting this variable
6462 prevents GDB from accessing memory outside the memory map. This
6463 is useful for targets with memory mapped registers or which react
6464 badly to accesses of unmapped address space.
6466 set breakpoint auto-hw
6467 show breakpoint auto-hw
6468 If the target supplies a memory map, for instance via the remote
6469 protocol's "qXfer:memory-map:read" packet, setting this variable
6470 lets GDB use hardware breakpoints automatically for memory regions
6471 where it can not use software breakpoints. This covers both the
6472 "break" command and internal breakpoints used for other commands
6473 including "next" and "finish".
6476 catch exception unhandled
6477 Stop the program execution when Ada exceptions are raised.
6480 Stop the program execution when an Ada assertion failed.
6484 Set an alternate system root for target files. This is a more
6485 general version of "set solib-absolute-prefix", which is now
6486 an alias to "set sysroot".
6489 Provide extended SPU facility status information. This set of
6490 commands is available only when debugging the Cell/B.E. SPU
6493 * New native configurations
6495 OpenBSD/sh sh*-*openbsd*
6498 unset tdesc filename
6500 Use the specified local file as an XML target description, and do
6501 not query the target for its built-in description.
6505 OpenBSD/sh sh*-*-openbsd*
6506 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
6507 Toshiba Media Processor mep-elf
6509 * New remote packets
6512 Ignore the specified signals; pass them directly to the debugged program
6513 without stopping other threads or reporting them to GDB.
6515 qXfer:features:read:
6516 Read an XML target description from the target, which describes its
6521 Read or write contents of an spufs file on the target system. These
6522 packets are available only on the Cell/B.E. SPU architecture.
6524 qXfer:libraries:read:
6525 Report the loaded shared libraries. Combined with new "T" packet
6526 response, this packet allows GDB to debug shared libraries on
6527 targets where the operating system manages the list of loaded
6528 libraries (e.g. Windows and SymbianOS).
6532 Support for these obsolete configurations has been removed.
6540 i[34567]86-*-lynxos*
6541 i[34567]86-*-netware*
6542 i[34567]86-*-sco3.2v5*
6543 i[34567]86-*-sco3.2v4*
6545 i[34567]86-*-sysv4.2*
6548 i[34567]86-*-unixware2*
6549 i[34567]86-*-unixware*
6558 * Other removed features
6565 Various m68k-only ROM monitors.
6572 Various Renesas ROM monitors and debugging interfaces for SH and
6577 Support for a Macraigor serial interface to on-chip debugging.
6578 GDB does not directly support the newer parallel or USB
6583 A debug information format. The predecessor to DWARF 2 and
6584 DWARF 3, which are still supported.
6586 Support for the HP aCC compiler on HP-UX/PA-RISC
6588 SOM-encapsulated symbolic debugging information, automatic
6589 invocation of pxdb, and the aCC custom C++ ABI. This does not
6590 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
6591 with aCC can still be debugged on an assembly level.
6593 MIPS ".pdr" sections
6595 A MIPS-specific format used to describe stack frame layout
6596 in debugging information.
6600 GDB could work with an older version of Guile to debug
6601 the interpreter and Scheme programs running in it.
6603 set mips stack-arg-size
6604 set mips saved-gpreg-size
6606 Use "set mips abi" to control parameter passing for MIPS.
6608 *** Changes in GDB 6.6
6613 Cell Broadband Engine SPU spu-elf
6615 * GDB can now be configured as a cross-debugger targeting native Windows
6616 (mingw32) or Cygwin. It can communicate with a remote debugging stub
6617 running on a Windows system over TCP/IP to debug Windows programs.
6619 * The GDB remote stub, gdbserver, has been updated to support Windows and
6620 Cygwin debugging. Both single-threaded and multi-threaded programs are
6623 * The "set trust-readonly-sections" command works again. This command was
6624 broken in GDB 6.3, 6.4, and 6.5.
6626 * The "load" command now supports writing to flash memory, if the remote
6627 stub provides the required support.
6629 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
6630 longer requires symbolic debug information (e.g. DWARF-2).
6635 unset substitute-path
6636 show substitute-path
6637 Manage a list of substitution rules that GDB uses to rewrite the name
6638 of the directories where the sources are located. This can be useful
6639 for instance when the sources were moved to a different location
6640 between compilation and debugging.
6644 Print each CLI command as it is executed. Each command is prefixed with
6645 a number of `+' symbols representing the nesting depth.
6646 The source command now has a `-v' option to enable the same feature.
6650 The ARM Demon monitor support (RDP protocol, "target rdp").
6652 Kernel Object Display, an embedded debugging feature which only worked with
6653 an obsolete version of Cisco IOS.
6655 The 'set download-write-size' and 'show download-write-size' commands.
6657 * New remote packets
6660 Tell a stub about GDB client features, and request remote target features.
6661 The first feature implemented is PacketSize, which allows the target to
6662 specify the size of packets it can handle - to minimize the number of
6663 packets required and improve performance when connected to a remote
6667 Fetch an OS auxilliary vector from the remote stub. This packet is a
6668 more efficient replacement for qPart:auxv:read.
6670 qXfer:memory-map:read:
6671 Fetch a memory map from the remote stub, including information about
6672 RAM, ROM, and flash memory devices.
6677 Erase and program a flash memory device.
6679 * Removed remote packets
6682 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
6683 used it, and only gdbserver implemented it.
6685 *** Changes in GDB 6.5
6689 Renesas M32C/M16C m32c-elf
6691 Morpho Technologies ms1 ms1-elf
6695 init-if-undefined Initialize a convenience variable, but
6696 only if it doesn't already have a value.
6698 The following commands are presently only implemented for native GNU/Linux:
6700 checkpoint Save a snapshot of the program state.
6702 restart <n> Return the program state to a
6703 previously saved state.
6705 info checkpoints List currently saved checkpoints.
6707 delete-checkpoint <n> Delete a previously saved checkpoint.
6709 set|show detach-on-fork Tell gdb whether to detach from a newly
6710 forked process, or to keep debugging it.
6712 info forks List forks of the user program that
6713 are available to be debugged.
6715 fork <n> Switch to debugging one of several
6716 forks of the user program that are
6717 available to be debugged.
6719 delete-fork <n> Delete a fork from the list of forks
6720 that are available to be debugged (and
6721 kill the forked process).
6723 detach-fork <n> Delete a fork from the list of forks
6724 that are available to be debugged (and
6725 allow the process to continue).
6729 Morpho Technologies ms2 ms1-elf
6731 * Improved Windows host support
6733 GDB now builds as a cross debugger hosted on i686-mingw32, including
6734 native console support, and remote communications using either
6735 network sockets or serial ports.
6737 * Improved Modula-2 language support
6739 GDB can now print most types in the Modula-2 syntax. This includes:
6740 basic types, set types, record types, enumerated types, range types,
6741 pointer types and ARRAY types. Procedure var parameters are correctly
6742 printed and hexadecimal addresses and character constants are also
6743 written in the Modula-2 syntax. Best results can be obtained by using
6744 GNU Modula-2 together with the -gdwarf-2 command line option.
6748 The ARM rdi-share module.
6750 The Netware NLM debug server.
6752 *** Changes in GDB 6.4
6754 * New native configurations
6756 OpenBSD/arm arm*-*-openbsd*
6757 OpenBSD/mips64 mips64-*-openbsd*
6761 Morpho Technologies ms1 ms1-elf
6763 * New command line options
6765 --batch-silent As for --batch, but totally silent.
6766 --return-child-result The debugger will exist with the same value
6767 the child (debugged) program exited with.
6768 --eval-command COMMAND, -ex COMMAND
6769 Execute a single GDB CLI command. This may be
6770 specified multiple times and in conjunction
6771 with the --command (-x) option.
6773 * Deprecated commands removed
6775 The following commands, that were deprecated in 2000, have been
6779 set|show arm disassembly-flavor set|show arm disassembler
6780 othernames set arm disassembler
6781 set|show remotedebug set|show debug remote
6782 set|show archdebug set|show debug arch
6783 set|show eventdebug set|show debug event
6786 * New BSD user-level threads support
6788 It is now possible to debug programs using the user-level threads
6789 library on OpenBSD and FreeBSD. Currently supported (target)
6792 FreeBSD/amd64 x86_64-*-freebsd*
6793 FreeBSD/i386 i386-*-freebsd*
6794 OpenBSD/i386 i386-*-openbsd*
6796 Note that the new kernel threads libraries introduced in FreeBSD 5.x
6797 are not yet supported.
6799 * New support for Matsushita MN10300 w/sim added
6800 (Work in progress). mn10300-elf.
6802 * REMOVED configurations and files
6804 VxWorks and the XDR protocol *-*-vxworks
6805 Motorola MCORE mcore-*-*
6806 National Semiconductor NS32000 ns32k-*-*
6808 * New "set print array-indexes" command
6810 After turning this setting "on", GDB prints the index of each element
6811 when displaying arrays. The default is "off" to preserve the previous
6814 * VAX floating point support
6816 GDB now supports the not-quite-ieee VAX F and D floating point formats.
6818 * User-defined command support
6820 In addition to using $arg0..$arg9 for argument passing, it is now possible
6821 to use $argc to determine now many arguments have been passed. See the
6822 section on user-defined commands in the user manual for more information.
6824 *** Changes in GDB 6.3:
6826 * New command line option
6828 GDB now accepts -l followed by a number to set the timeout for remote
6831 * GDB works with GCC -feliminate-dwarf2-dups
6833 GDB now supports a more compact representation of DWARF-2 debug
6834 information using DW_FORM_ref_addr references. These are produced
6835 by GCC with the option -feliminate-dwarf2-dups and also by some
6836 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
6837 to use -feliminate-dwarf2-dups.
6839 * Internationalization
6841 When supported by the host system, GDB will be built with
6842 internationalization (libintl). The task of marking up the sources is
6843 continued, we're looking forward to our first translation.
6847 Initial support for debugging programs compiled with the GNAT
6848 implementation of the Ada programming language has been integrated
6849 into GDB. In this release, support is limited to expression evaluation.
6851 * New native configurations
6853 GNU/Linux/m32r m32r-*-linux-gnu
6857 GDB's remote protocol now includes support for the 'p' packet. This
6858 packet is used to fetch individual registers from a remote inferior.
6860 * END-OF-LIFE registers[] compatibility module
6862 GDB's internal register infrastructure has been completely rewritten.
6863 The new infrastructure making possible the implementation of key new
6864 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
6867 GDB 6.3 will be the last release to include the registers[]
6868 compatibility module that allowed out-of-date configurations to
6869 continue to work. This change directly impacts the following
6879 powerpc bdm protocol
6881 Unless there is activity to revive these configurations, they will be
6882 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
6884 * OBSOLETE configurations and files
6886 Configurations that have been declared obsolete in this release have
6887 been commented out. Unless there is activity to revive these
6888 configurations, the next release of GDB will have their sources
6889 permanently REMOVED.
6898 *** Changes in GDB 6.2.1:
6900 * MIPS `break main; run' gave an heuristic-fence-post warning
6902 When attempting to run even a simple program, a warning about
6903 heuristic-fence-post being hit would be reported. This problem has
6906 * MIPS IRIX 'long double' crashed GDB
6908 When examining a long double variable, GDB would get a segmentation
6909 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
6910 IRIX long double values).
6914 A bug in the VAX stack code was causing problems with the "next"
6915 command. This problem has been fixed.
6917 *** Changes in GDB 6.2:
6919 * Fix for ``many threads''
6921 On GNU/Linux systems that use the NPTL threads library, a program
6922 rapidly creating and deleting threads would confuse GDB leading to the
6925 ptrace: No such process.
6926 thread_db_get_info: cannot get thread info: generic error
6928 This problem has been fixed.
6930 * "-async" and "-noasync" options removed.
6932 Support for the broken "-noasync" option has been removed (it caused
6935 * New ``start'' command.
6937 This command runs the program until the beginning of the main procedure.
6939 * New BSD Kernel Data Access Library (libkvm) interface
6941 Using ``target kvm'' it is now possible to debug kernel core dumps and
6942 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
6943 platforms. Currently supported (native-only) configurations are:
6945 FreeBSD/amd64 x86_64-*-freebsd*
6946 FreeBSD/i386 i?86-*-freebsd*
6947 NetBSD/i386 i?86-*-netbsd*
6948 NetBSD/m68k m68*-*-netbsd*
6949 NetBSD/sparc sparc-*-netbsd*
6950 OpenBSD/amd64 x86_64-*-openbsd*
6951 OpenBSD/i386 i?86-*-openbsd*
6952 OpenBSD/m68k m68*-openbsd*
6953 OpenBSD/sparc sparc-*-openbsd*
6955 * Signal trampoline code overhauled
6957 Many generic problems with GDB's signal handling code have been fixed.
6958 These include: backtraces through non-contiguous stacks; recognition
6959 of sa_sigaction signal trampolines; backtrace from a NULL pointer
6960 call; backtrace through a signal trampoline; step into and out of
6961 signal handlers; and single-stepping in the signal trampoline.
6963 Please note that kernel bugs are a limiting factor here. These
6964 features have been shown to work on an s390 GNU/Linux system that
6965 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
6967 * Cygwin support for DWARF 2 added.
6969 * New native configurations
6971 GNU/Linux/hppa hppa*-*-linux*
6972 OpenBSD/hppa hppa*-*-openbsd*
6973 OpenBSD/m68k m68*-*-openbsd*
6974 OpenBSD/m88k m88*-*-openbsd*
6975 OpenBSD/powerpc powerpc-*-openbsd*
6976 NetBSD/vax vax-*-netbsd*
6977 OpenBSD/vax vax-*-openbsd*
6979 * END-OF-LIFE frame compatibility module
6981 GDB's internal frame infrastructure has been completely rewritten.
6982 The new infrastructure making it possible to support key new features
6983 including DWARF 2 Call Frame Information. To aid in the task of
6984 migrating old configurations to this new infrastructure, a
6985 compatibility module, that allowed old configurations to continue to
6986 work, was also included.
6988 GDB 6.2 will be the last release to include this frame compatibility
6989 module. This change directly impacts the following configurations:
6999 Unless there is activity to revive these configurations, they will be
7000 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
7002 * REMOVED configurations and files
7004 Sun 3, running SunOS 3 m68*-*-sunos3*
7005 Sun 3, running SunOS 4 m68*-*-sunos4*
7006 Sun 2, running SunOS 3 m68000-*-sunos3*
7007 Sun 2, running SunOS 4 m68000-*-sunos4*
7008 Motorola 680x0 running LynxOS m68*-*-lynxos*
7009 AT&T 3b1/Unix pc m68*-att-*
7010 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
7011 decstation mips-dec-* mips-little-*
7012 riscos mips-*-riscos* mips-*-sysv*
7013 sonymips mips-sony-*
7014 sysv mips*-*-sysv4* (IRIX 5/6 not included)
7016 *** Changes in GDB 6.1.1:
7018 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
7020 The TUI (Text-mode User Interface) is now built as part of a default
7021 GDB configuration. It is enabled by either selecting the TUI with the
7022 command line option "-i=tui" or by running the separate "gdbtui"
7023 program. For more information on the TUI, see the manual "Debugging
7026 * Pending breakpoint support (also included in GDB 6.1)
7028 Support has been added to allow you to specify breakpoints in shared
7029 libraries that have not yet been loaded. If a breakpoint location
7030 cannot be found, and the "breakpoint pending" option is set to auto,
7031 GDB queries you if you wish to make the breakpoint pending on a future
7032 shared-library load. If and when GDB resolves the breakpoint symbol,
7033 the pending breakpoint is removed as one or more regular breakpoints
7036 Pending breakpoints are very useful for GCJ Java debugging.
7038 * Fixed ISO-C build problems
7040 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
7041 non ISO-C code that stopped them being built using a more strict ISO-C
7042 compiler (e.g., IBM's C compiler).
7044 * Fixed build problem on IRIX 5
7046 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
7047 wasn't able to compile compile on an IRIX 5 system.
7049 * Added execute permission to gdb/gdbserver/configure
7051 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
7052 permission. This bug would cause configure to fail on a number of
7053 systems (Solaris, IRIX). Ref: server/519.
7055 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
7057 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
7058 has been updated to use constant array sizes.
7060 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
7062 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
7063 its generated DWARF Call Frame Info. This encoding was causing GDB to
7064 panic, that panic has been fixed. Ref: gdb/1628.
7066 * Fixed a problem when examining parameters in shared library code.
7068 When examining parameters in optimized shared library code generated
7069 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
7070 not available''. GDB now correctly displays the variable's value.
7072 *** Changes in GDB 6.1:
7074 * Removed --with-mmalloc
7076 Support for the mmalloc memory manager has been removed, as it
7077 conflicted with the internal gdb byte cache.
7079 * Changes in AMD64 configurations
7081 The AMD64 target now includes the %cs and %ss registers. As a result
7082 the AMD64 remote protocol has changed; this affects the floating-point
7083 and SSE registers. If you rely on those registers for your debugging,
7084 you should upgrade gdbserver on the remote side.
7086 * Revised SPARC target
7088 The SPARC target has been completely revised, incorporating the
7089 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
7090 support for LynxOS and SunOS 4 has been dropped. Calling functions
7091 from within GDB on operating systems with a non-executable stack
7092 (Solaris, OpenBSD) now works.
7096 GDB has a new C++ demangler which does a better job on the mangled
7097 names generated by current versions of g++. It also runs faster, so
7098 with this and other changes gdb should now start faster on large C++
7101 * DWARF 2 Location Expressions
7103 GDB support for location expressions has been extended to support function
7104 arguments and frame bases. Older versions of GDB could crash when they
7107 * C++ nested types and namespaces
7109 GDB's support for nested types and namespaces in C++ has been
7110 improved, especially if you use the DWARF 2 debugging format. (This
7111 is the default for recent versions of GCC on most platforms.)
7112 Specifically, if you have a class "Inner" defined within a class or
7113 namespace "Outer", then GDB realizes that the class's name is
7114 "Outer::Inner", not simply "Inner". This should greatly reduce the
7115 frequency of complaints about not finding RTTI symbols. In addition,
7116 if you are stopped at inside of a function defined within a namespace,
7117 GDB modifies its name lookup accordingly.
7119 * New native configurations
7121 NetBSD/amd64 x86_64-*-netbsd*
7122 OpenBSD/amd64 x86_64-*-openbsd*
7123 OpenBSD/alpha alpha*-*-openbsd*
7124 OpenBSD/sparc sparc-*-openbsd*
7125 OpenBSD/sparc64 sparc64-*-openbsd*
7127 * New debugging protocols
7129 M32R with SDI protocol m32r-*-elf*
7131 * "set prompt-escape-char" command deleted.
7133 The command "set prompt-escape-char" has been deleted. This command,
7134 and its very obscure effect on GDB's prompt, was never documented,
7135 tested, nor mentioned in the NEWS file.
7137 * OBSOLETE configurations and files
7139 Configurations that have been declared obsolete in this release have
7140 been commented out. Unless there is activity to revive these
7141 configurations, the next release of GDB will have their sources
7142 permanently REMOVED.
7144 Sun 3, running SunOS 3 m68*-*-sunos3*
7145 Sun 3, running SunOS 4 m68*-*-sunos4*
7146 Sun 2, running SunOS 3 m68000-*-sunos3*
7147 Sun 2, running SunOS 4 m68000-*-sunos4*
7148 Motorola 680x0 running LynxOS m68*-*-lynxos*
7149 AT&T 3b1/Unix pc m68*-att-*
7150 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
7151 decstation mips-dec-* mips-little-*
7152 riscos mips-*-riscos* mips-*-sysv*
7153 sonymips mips-sony-*
7154 sysv mips*-*-sysv4* (IRIX 5/6 not included)
7156 * REMOVED configurations and files
7158 SGI Irix-4.x mips-sgi-irix4 or iris4
7159 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
7160 Z8000 simulator z8k-zilog-none or z8ksim
7161 Matsushita MN10200 w/simulator mn10200-*-*
7162 H8/500 simulator h8500-hitachi-hms or h8500hms
7163 HP/PA running BSD hppa*-*-bsd*
7164 HP/PA running OSF/1 hppa*-*-osf*
7165 HP/PA Pro target hppa*-*-pro*
7166 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
7167 386BSD i[3456]86-*-bsd*
7168 Sequent family i[3456]86-sequent-sysv4*
7169 i[3456]86-sequent-sysv*
7170 i[3456]86-sequent-bsd*
7171 SPARC running LynxOS sparc-*-lynxos*
7172 SPARC running SunOS 4 sparc-*-sunos4*
7173 Tsqware Sparclet sparclet-*-*
7174 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
7176 *** Changes in GDB 6.0:
7180 Support for debugging the Objective-C programming language has been
7181 integrated into GDB.
7183 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
7185 DWARF 2's Call Frame Information makes available compiler generated
7186 information that more exactly describes the program's run-time stack.
7187 By using this information, GDB is able to provide more robust stack
7190 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
7191 have been updated to use a new backtrace mechanism which includes
7192 DWARF 2 CFI support.
7196 GDB's remote protocol has been extended to include support for hosted
7197 file I/O (where the remote target uses GDB's file system). See GDB's
7198 remote protocol documentation for details.
7200 * All targets using the new architecture framework.
7202 All of GDB's targets have been updated to use the new internal
7203 architecture framework. The way is now open for future GDB releases
7204 to include cross-architecture native debugging support (i386 on amd64,
7207 * GNU/Linux's Thread Local Storage (TLS)
7209 GDB now includes support for for the GNU/Linux implementation of
7210 per-thread variables.
7212 * GNU/Linux's Native POSIX Thread Library (NPTL)
7214 GDB's thread code has been updated to work with either the new
7215 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
7217 * Separate debug info.
7219 GDB, in conjunction with BINUTILS, now supports a mechanism for
7220 automatically loading debug information from a separate file. Instead
7221 of shipping full debug and non-debug versions of system libraries,
7222 system integrators can now instead ship just the stripped libraries
7223 and optional debug files.
7225 * DWARF 2 Location Expressions
7227 DWARF 2 Location Expressions allow the compiler to more completely
7228 describe the location of variables (even in optimized code) to the
7231 GDB now includes preliminary support for location expressions (support
7232 for DW_OP_piece is still missing).
7236 A number of long standing bugs that caused GDB to die while starting a
7237 Java application have been fixed. GDB's Java support is now
7238 considered "useable".
7240 * GNU/Linux support for fork, vfork, and exec.
7242 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
7243 commands are now implemented for GNU/Linux. They require a 2.5.x or later
7246 * GDB supports logging output to a file
7248 There are two new commands, "set logging" and "show logging", which can be
7249 used to capture GDB's output to a file.
7251 * The meaning of "detach" has changed for gdbserver
7253 The "detach" command will now resume the application, as documented. To
7254 disconnect from gdbserver and leave it stopped, use the new "disconnect"
7257 * d10v, m68hc11 `regs' command deprecated
7259 The `info registers' command has been updated so that it displays the
7260 registers using a format identical to the old `regs' command.
7264 A new command, "maint set profile on/off", has been added. This command can
7265 be used to enable or disable profiling while running GDB, to profile a
7266 session or a set of commands. In addition there is a new configure switch,
7267 "--enable-profiling", which will cause GDB to be compiled with profiling
7268 data, for more informative profiling results.
7270 * Default MI syntax changed to "mi2".
7272 The default MI (machine interface) syntax, enabled by the command line
7273 option "-i=mi", has been changed to "mi2". The previous MI syntax,
7274 "mi1", can be enabled by specifying the option "-i=mi1".
7276 Support for the original "mi0" syntax (included in GDB 5.0) has been
7279 Fix for gdb/192: removed extraneous space when displaying frame level.
7280 Fix for gdb/672: update changelist is now output in mi list format.
7281 Fix for gdb/702: a -var-assign that updates the value now shows up
7282 in a subsequent -var-update.
7284 * New native configurations.
7286 FreeBSD/amd64 x86_64-*-freebsd*
7288 * Multi-arched targets.
7290 HP/PA HPUX11 hppa*-*-hpux*
7291 Renesas M32R/D w/simulator m32r-*-elf*
7293 * OBSOLETE configurations and files
7295 Configurations that have been declared obsolete in this release have
7296 been commented out. Unless there is activity to revive these
7297 configurations, the next release of GDB will have their sources
7298 permanently REMOVED.
7300 Z8000 simulator z8k-zilog-none or z8ksim
7301 Matsushita MN10200 w/simulator mn10200-*-*
7302 H8/500 simulator h8500-hitachi-hms or h8500hms
7303 HP/PA running BSD hppa*-*-bsd*
7304 HP/PA running OSF/1 hppa*-*-osf*
7305 HP/PA Pro target hppa*-*-pro*
7306 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
7307 Sequent family i[3456]86-sequent-sysv4*
7308 i[3456]86-sequent-sysv*
7309 i[3456]86-sequent-bsd*
7310 Tsqware Sparclet sparclet-*-*
7311 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
7313 * REMOVED configurations and files
7316 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
7317 IBM AIX PS/2 i[3456]86-*-aix
7318 i386 running Mach 3.0 i[3456]86-*-mach3*
7319 i386 running Mach i[3456]86-*-mach*
7320 i386 running OSF/1 i[3456]86-*osf1mk*
7321 HP/Apollo 68k Family m68*-apollo*-sysv*,
7323 m68*-hp-bsd*, m68*-hp-hpux*
7324 Argonaut Risc Chip (ARC) arc-*-*
7325 Mitsubishi D30V d30v-*-*
7326 Fujitsu FR30 fr30-*-elf*
7327 OS/9000 i[34]86-*-os9k
7328 I960 with MON960 i960-*-coff
7330 * MIPS $fp behavior changed
7332 The convenience variable $fp, for the MIPS, now consistently returns
7333 the address of the current frame's base. Previously, depending on the
7334 context, $fp could refer to either $sp or the current frame's base
7335 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
7336 The GNU Source-Level Debugger''.
7338 *** Changes in GDB 5.3:
7340 * GNU/Linux shared library multi-threaded performance improved.
7342 When debugging a multi-threaded application on GNU/Linux, GDB now uses
7343 `/proc', in preference to `ptrace' for memory reads. This may result
7344 in an improvement in the start-up time of multi-threaded, shared
7345 library applications when run under GDB. One GDB user writes: ``loads
7346 shared libs like mad''.
7348 * ``gdbserver'' now supports multi-threaded applications on some targets
7350 Support for debugging multi-threaded applications which use
7351 the GNU/Linux LinuxThreads package has been added for
7352 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
7353 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
7355 * GDB now supports C/C++ preprocessor macros.
7357 GDB now expands preprocessor macro invocations in C/C++ expressions,
7358 and provides various commands for showing macro definitions and how
7361 The new command `macro expand EXPRESSION' expands any macro
7362 invocations in expression, and shows the result.
7364 The new command `show macro MACRO-NAME' shows the definition of the
7365 macro named MACRO-NAME, and where it was defined.
7367 Most compilers don't include information about macros in the debugging
7368 information by default. In GCC 3.1, for example, you need to compile
7369 your program with the options `-gdwarf-2 -g3'. If the macro
7370 information is present in the executable, GDB will read it.
7372 * Multi-arched targets.
7374 DEC Alpha (partial) alpha*-*-*
7375 DEC VAX (partial) vax-*-*
7377 National Semiconductor NS32000 (partial) ns32k-*-*
7378 Motorola 68000 (partial) m68k-*-*
7379 Motorola MCORE mcore-*-*
7383 Fujitsu FRV architecture added by Red Hat frv*-*-*
7386 * New native configurations
7388 Alpha NetBSD alpha*-*-netbsd*
7389 SH NetBSD sh*-*-netbsdelf*
7390 MIPS NetBSD mips*-*-netbsd*
7391 UltraSPARC NetBSD sparc64-*-netbsd*
7393 * OBSOLETE configurations and files
7395 Configurations that have been declared obsolete in this release have
7396 been commented out. Unless there is activity to revive these
7397 configurations, the next release of GDB will have their sources
7398 permanently REMOVED.
7400 Mitsubishi D30V d30v-*-*
7401 OS/9000 i[34]86-*-os9k
7402 IBM AIX PS/2 i[3456]86-*-aix
7403 Fujitsu FR30 fr30-*-elf*
7404 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
7405 Argonaut Risc Chip (ARC) arc-*-*
7406 i386 running Mach 3.0 i[3456]86-*-mach3*
7407 i386 running Mach i[3456]86-*-mach*
7408 i386 running OSF/1 i[3456]86-*osf1mk*
7409 HP/Apollo 68k Family m68*-apollo*-sysv*,
7411 m68*-hp-bsd*, m68*-hp-hpux*
7412 I960 with MON960 i960-*-coff
7414 * OBSOLETE languages
7416 CHILL, a Pascal like language used by telecommunications companies.
7418 * REMOVED configurations and files
7420 AMD 29k family via UDI a29k-amd-udi, udi29k
7421 A29K VxWorks a29k-*-vxworks
7422 AMD 29000 embedded, using EBMON a29k-none-none
7423 AMD 29000 embedded with COFF a29k-none-coff
7424 AMD 29000 embedded with a.out a29k-none-aout
7426 testsuite/gdb.hp/gdb.threads-hp/ directory
7428 * New command "set max-user-call-depth <nnn>"
7430 This command allows the user to limit the call depth of user-defined
7431 commands. The default is 1024.
7433 * Changes in FreeBSD/i386 native debugging.
7435 Support for the "generate-core-file" has been added.
7437 * New commands "dump", "append", and "restore".
7439 These commands allow data to be copied from target memory
7440 to a bfd-format or binary file (dump and append), and back
7441 from a file into memory (restore).
7443 * Improved "next/step" support on multi-processor Alpha Tru64.
7445 The previous single-step mechanism could cause unpredictable problems,
7446 including the random appearance of SIGSEGV or SIGTRAP signals. The use
7447 of a software single-step mechanism prevents this.
7449 *** Changes in GDB 5.2.1:
7457 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
7458 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
7459 Fix, by Joel Brobecker imported from mainline.
7461 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
7462 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
7463 Fix, by Fred Fish, imported from mainline.
7465 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
7466 Surprisingly enough, it works now.
7467 By Michal Ludvig, imported from mainline.
7469 i386 hardware watchpoint support:
7470 avoid misses on second run for some targets.
7471 By Pierre Muller, imported from mainline.
7473 *** Changes in GDB 5.2:
7475 * New command "set trust-readonly-sections on[off]".
7477 This command is a hint that tells gdb that read-only sections
7478 really are read-only (ie. that their contents will not change).
7479 In this mode, gdb will go to the object file rather than the
7480 target to read memory from read-only sections (such as ".text").
7481 This can be a significant performance improvement on some
7482 (notably embedded) targets.
7484 * New command "generate-core-file" (or "gcore").
7486 This new gdb command allows the user to drop a core file of the child
7487 process state at any time. So far it's been implemented only for
7488 GNU/Linux and Solaris, but should be relatively easily ported to other
7489 hosts. Argument is core file name (defaults to core.<pid>).
7491 * New command line option
7493 GDB now accepts --pid or -p followed by a process id.
7495 * Change in command line behavior -- corefiles vs. process ids.
7497 There is a subtle behavior in the way in which GDB handles
7498 command line arguments. The first non-flag argument is always
7499 a program to debug, but the second non-flag argument may either
7500 be a corefile or a process id. Previously, GDB would attempt to
7501 open the second argument as a corefile, and if that failed, would
7502 issue a superfluous error message and then attempt to attach it as
7503 a process. Now, if the second argument begins with a non-digit,
7504 it will be treated as a corefile. If it begins with a digit,
7505 GDB will attempt to attach it as a process, and if no such process
7506 is found, will then attempt to open it as a corefile.
7508 * Changes in ARM configurations.
7510 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
7511 configuration is fully multi-arch.
7513 * New native configurations
7515 ARM NetBSD arm*-*-netbsd*
7516 x86 OpenBSD i[3456]86-*-openbsd*
7517 AMD x86-64 running GNU/Linux x86_64-*-linux-*
7518 Sparc64 running FreeBSD sparc64-*-freebsd*
7522 Sanyo XStormy16 xstormy16-elf
7524 * OBSOLETE configurations and files
7526 Configurations that have been declared obsolete in this release have
7527 been commented out. Unless there is activity to revive these
7528 configurations, the next release of GDB will have their sources
7529 permanently REMOVED.
7531 AMD 29k family via UDI a29k-amd-udi, udi29k
7532 A29K VxWorks a29k-*-vxworks
7533 AMD 29000 embedded, using EBMON a29k-none-none
7534 AMD 29000 embedded with COFF a29k-none-coff
7535 AMD 29000 embedded with a.out a29k-none-aout
7537 testsuite/gdb.hp/gdb.threads-hp/ directory
7539 * REMOVED configurations and files
7541 TI TMS320C80 tic80-*-*
7543 PowerPC Solaris powerpcle-*-solaris*
7544 PowerPC Windows NT powerpcle-*-cygwin32
7545 PowerPC Netware powerpc-*-netware*
7546 Harris/CXUX m88k m88*-harris-cxux*
7547 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
7548 ns32k-utek-sysv* ns32k-utek-*
7549 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
7550 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
7551 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
7552 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
7553 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
7555 * Changes to command line processing
7557 The new `--args' feature can be used to specify command-line arguments
7558 for the inferior from gdb's command line.
7560 * Changes to key bindings
7562 There is a new `operate-and-get-next' function bound to `C-o'.
7564 *** Changes in GDB 5.1.1
7566 Fix compile problem on DJGPP.
7568 Fix a problem with floating-point registers on the i386 being
7571 Fix to stop GDB crashing on .debug_str debug info.
7573 Numerous documentation fixes.
7575 Numerous testsuite fixes.
7577 *** Changes in GDB 5.1:
7579 * New native configurations
7581 Alpha FreeBSD alpha*-*-freebsd*
7582 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
7583 MIPS GNU/Linux mips*-*-linux*
7584 MIPS SGI Irix 6.x mips*-sgi-irix6*
7585 ia64 AIX ia64-*-aix*
7586 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
7590 Motorola 68HC11 and 68HC12 m68hc11-elf
7592 UltraSparc running GNU/Linux sparc64-*-linux*
7594 * OBSOLETE configurations and files
7596 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
7597 Harris/CXUX m88k m88*-harris-cxux*
7598 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
7599 ns32k-utek-sysv* ns32k-utek-*
7600 TI TMS320C80 tic80-*-*
7602 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
7603 PowerPC Solaris powerpcle-*-solaris*
7604 PowerPC Windows NT powerpcle-*-cygwin32
7605 PowerPC Netware powerpc-*-netware*
7606 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
7607 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
7608 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
7609 Apple Macintosh (MPW) host N/A
7611 stuff.c (Program to stuff files into a specially prepared space in kdb)
7612 kdb-start.c (Main loop for the standalone kernel debugger)
7614 Configurations that have been declared obsolete in this release have
7615 been commented out. Unless there is activity to revive these
7616 configurations, the next release of GDB will have their sources
7617 permanently REMOVED.
7619 * REMOVED configurations and files
7621 Altos 3068 m68*-altos-*
7622 Convex c1-*-*, c2-*-*
7624 ARM RISCix arm-*-* (as host)
7628 * GDB has been converted to ISO C.
7630 GDB's source code has been converted to ISO C. In particular, the
7631 sources are fully protoized, and rely on standard headers being
7636 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
7638 * The MI enabled by default.
7640 The new machine oriented interface (MI) introduced in GDB 5.0 has been
7641 revised and enabled by default. Packages which use GDB as a debugging
7642 engine behind a UI or another front end are encouraged to switch to
7643 using the GDB/MI interface, instead of the old annotations interface
7644 which is now deprecated.
7646 * Support for debugging Pascal programs.
7648 GDB now includes support for debugging Pascal programs. The following
7649 main features are supported:
7651 - Pascal-specific data types such as sets;
7653 - automatic recognition of Pascal sources based on file-name
7656 - Pascal-style display of data types, variables, and functions;
7658 - a Pascal expression parser.
7660 However, some important features are not yet supported.
7662 - Pascal string operations are not supported at all;
7664 - there are some problems with boolean types;
7666 - Pascal type hexadecimal constants are not supported
7667 because they conflict with the internal variables format;
7669 - support for Pascal objects and classes is not full yet;
7671 - unlike Pascal, GDB is case-sensitive for symbol names.
7673 * Changes in completion.
7675 Commands such as `shell', `run' and `set args', which pass arguments
7676 to inferior programs, now complete on file names, similar to what
7677 users expect at the shell prompt.
7679 Commands which accept locations, such as `disassemble', `print',
7680 `breakpoint', `until', etc. now complete on filenames as well as
7681 program symbols. Thus, if you type "break foob TAB", and the source
7682 files linked into the programs include `foobar.c', that file name will
7683 be one of the candidates for completion. However, file names are not
7684 considered for completion after you typed a colon that delimits a file
7685 name from a name of a function in that file, as in "break foo.c:bar".
7687 `set demangle-style' completes on available demangling styles.
7689 * New platform-independent commands:
7691 It is now possible to define a post-hook for a command as well as a
7692 hook that runs before the command. For more details, see the
7693 documentation of `hookpost' in the GDB manual.
7695 * Changes in GNU/Linux native debugging.
7697 Support for debugging multi-threaded programs has been completely
7698 revised for all platforms except m68k and sparc. You can now debug as
7699 many threads as your system allows you to have.
7701 Attach/detach is supported for multi-threaded programs.
7703 Support for SSE registers was added for x86. This doesn't work for
7704 multi-threaded programs though.
7706 * Changes in MIPS configurations.
7708 Multi-arch support is enabled for all MIPS configurations.
7710 GDB can now be built as native debugger on SGI Irix 6.x systems for
7711 debugging n32 executables. (Debugging 64-bit executables is not yet
7714 * Unified support for hardware watchpoints in all x86 configurations.
7716 Most (if not all) native x86 configurations support hardware-assisted
7717 breakpoints and watchpoints in a unified manner. This support
7718 implements debug register sharing between watchpoints, which allows to
7719 put a virtually infinite number of watchpoints on the same address,
7720 and also supports watching regions up to 16 bytes with several debug
7723 The new maintenance command `maintenance show-debug-regs' toggles
7724 debugging print-outs in functions that insert, remove, and test
7725 watchpoints and hardware breakpoints.
7727 * Changes in the DJGPP native configuration.
7729 New command ``info dos sysinfo'' displays assorted information about
7730 the CPU, OS, memory, and DPMI server.
7732 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
7733 display information about segment descriptors stored in GDT, LDT, and
7736 New commands ``info dos pde'' and ``info dos pte'' display entries
7737 from Page Directory and Page Tables (for now works with CWSDPMI only).
7738 New command ``info dos address-pte'' displays the Page Table entry for
7739 a given linear address.
7741 GDB can now pass command lines longer than 126 characters to the
7742 program being debugged (requires an update to the libdbg.a library
7743 which is part of the DJGPP development kit).
7745 DWARF2 debug info is now supported.
7747 It is now possible to `step' and `next' through calls to `longjmp'.
7749 * Changes in documentation.
7751 All GDB documentation was converted to GFDL, the GNU Free
7752 Documentation License.
7754 Tracepoints-related commands are now fully documented in the GDB
7757 TUI, the Text-mode User Interface, is now documented in the manual.
7759 Tracepoints-related commands are now fully documented in the GDB
7762 The "GDB Internals" manual now has an index. It also includes
7763 documentation of `ui_out' functions, GDB coding standards, x86
7764 hardware watchpoints, and memory region attributes.
7766 * GDB's version number moved to ``version.in''
7768 The Makefile variable VERSION has been replaced by the file
7769 ``version.in''. People creating GDB distributions should update the
7770 contents of this file.
7774 GUD support is now a standard part of the EMACS distribution.
7776 *** Changes in GDB 5.0:
7778 * Improved support for debugging FP programs on x86 targets
7780 Unified and much-improved support for debugging floating-point
7781 programs on all x86 targets. In particular, ``info float'' now
7782 displays the FP registers in the same format on all x86 targets, with
7783 greater level of detail.
7785 * Improvements and bugfixes in hardware-assisted watchpoints
7787 It is now possible to watch array elements, struct members, and
7788 bitfields with hardware-assisted watchpoints. Data-read watchpoints
7789 on x86 targets no longer erroneously trigger when the address is
7792 * Improvements in the native DJGPP version of GDB
7794 The distribution now includes all the scripts and auxiliary files
7795 necessary to build the native DJGPP version on MS-DOS/MS-Windows
7796 machines ``out of the box''.
7798 The DJGPP version can now debug programs that use signals. It is
7799 possible to catch signals that happened in the debuggee, deliver
7800 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
7801 would kill the program being debugged.) Programs that hook hardware
7802 interrupts (keyboard, timer, etc.) can also be debugged.
7804 It is now possible to debug DJGPP programs that redirect their
7805 standard handles or switch them to raw (as opposed to cooked) mode, or
7806 even close them. The command ``run < foo > bar'' works as expected,
7807 and ``info terminal'' reports useful information about the debuggee's
7808 terminal, including raw/cooked mode, redirection, etc.
7810 The DJGPP version now uses termios functions for console I/O, which
7811 enables debugging graphics programs. Interrupting GDB with Ctrl-C
7814 DOS-style file names with drive letters are now fully supported by
7817 It is now possible to debug DJGPP programs that switch their working
7818 directory. It is also possible to rerun the debuggee any number of
7819 times without restarting GDB; thus, you can use the same setup,
7820 breakpoints, etc. for many debugging sessions.
7822 * New native configurations
7824 ARM GNU/Linux arm*-*-linux*
7825 PowerPC GNU/Linux powerpc-*-linux*
7829 Motorola MCore mcore-*-*
7830 x86 VxWorks i[3456]86-*-vxworks*
7831 PowerPC VxWorks powerpc-*-vxworks*
7832 TI TMS320C80 tic80-*-*
7834 * OBSOLETE configurations
7836 Altos 3068 m68*-altos-*
7837 Convex c1-*-*, c2-*-*
7839 ARM RISCix arm-*-* (as host)
7842 Configurations that have been declared obsolete will be commented out,
7843 but the code will be left in place. If there is no activity to revive
7844 these configurations before the next release of GDB, the sources will
7845 be permanently REMOVED.
7847 * Gould support removed
7849 Support for the Gould PowerNode and NP1 has been removed.
7851 * New features for SVR4
7853 On SVR4 native platforms (such as Solaris), if you attach to a process
7854 without first loading a symbol file, GDB will now attempt to locate and
7855 load symbols from the running process's executable file.
7857 * Many C++ enhancements
7859 C++ support has been greatly improved. Overload resolution now works properly
7860 in almost all cases. RTTI support is on the way.
7862 * Remote targets can connect to a sub-program
7864 A popen(3) style serial-device has been added. This device starts a
7865 sub-process (such as a stand-alone simulator) and then communicates
7866 with that. The sub-program to run is specified using the syntax
7867 ``|<program> <args>'' vis:
7869 (gdb) set remotedebug 1
7870 (gdb) target extended-remote |mn10300-elf-sim program-args
7872 * MIPS 64 remote protocol
7874 A long standing bug in the mips64 remote protocol where by GDB
7875 expected certain 32 bit registers (ex SR) to be transfered as 32
7876 instead of 64 bits has been fixed.
7878 The command ``set remote-mips64-transfers-32bit-regs on'' has been
7879 added to provide backward compatibility with older versions of GDB.
7881 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
7883 The command ``set remotebinarydownload'' command has been replaced by
7884 ``set remote X-packet''. Other commands in ``set remote'' family
7885 include ``set remote P-packet''.
7887 * Breakpoint commands accept ranges.
7889 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
7890 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
7891 ``tracepoint passcount'' also accepts a range of tracepoints.
7893 * ``apropos'' command added.
7895 The ``apropos'' command searches through command names and
7896 documentation strings, printing out matches, making it much easier to
7897 try to find a command that does what you are looking for.
7901 A new machine oriented interface (MI) has been added to GDB. This
7902 interface is designed for debug environments running GDB as a separate
7903 process. This is part of the long term libGDB project. See the
7904 "GDB/MI" chapter of the GDB manual for further information. It can be
7905 enabled by configuring with:
7907 .../configure --enable-gdbmi
7909 *** Changes in GDB-4.18:
7911 * New native configurations
7913 HP-UX 10.20 hppa*-*-hpux10.20
7914 HP-UX 11.x hppa*-*-hpux11.0*
7915 M68K GNU/Linux m68*-*-linux*
7919 Fujitsu FR30 fr30-*-elf*
7920 Intel StrongARM strongarm-*-*
7921 Mitsubishi D30V d30v-*-*
7923 * OBSOLETE configurations
7925 Gould PowerNode, NP1 np1-*-*, pn-*-*
7927 Configurations that have been declared obsolete will be commented out,
7928 but the code will be left in place. If there is no activity to revive
7929 these configurations before the next release of GDB, the sources will
7930 be permanently REMOVED.
7934 As a compatibility experiment, GDB's source files buildsym.h and
7935 buildsym.c have been converted to pure standard C, no longer
7936 containing any K&R compatibility code. We believe that all systems in
7937 use today either come with a standard C compiler, or have a GCC port
7938 available. If this is not true, please report the affected
7939 configuration to bug-gdb@gnu.org immediately. See the README file for
7940 information about getting a standard C compiler if you don't have one
7945 GDB now uses readline 2.2.
7947 * set extension-language
7949 You can now control the mapping between filename extensions and source
7950 languages by using the `set extension-language' command. For instance,
7951 you can ask GDB to treat .c files as C++ by saying
7952 set extension-language .c c++
7953 The command `info extensions' lists all of the recognized extensions
7954 and their associated languages.
7956 * Setting processor type for PowerPC and RS/6000
7958 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
7959 you can use the `set processor' command to specify what variant of the
7960 PowerPC family you are debugging. The command
7964 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
7965 following PowerPC and RS6000 variants:
7967 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
7968 rs6000 IBM RS6000 ("POWER") architecture, user-level view
7970 403GC IBM PowerPC 403GC
7971 505 Motorola PowerPC 505
7972 860 Motorola PowerPC 860 or 850
7973 601 Motorola PowerPC 601
7974 602 Motorola PowerPC 602
7975 603 Motorola/IBM PowerPC 603 or 603e
7976 604 Motorola PowerPC 604 or 604e
7977 750 Motorola/IBM PowerPC 750 or 750
7979 At the moment, this command just tells GDB what to name the
7980 special-purpose processor registers. Since almost all the affected
7981 registers are inaccessible to user-level programs, this command is
7982 only useful for remote debugging in its present form.
7986 Thanks to a major code donation from Hewlett-Packard, GDB now has much
7987 more extensive support for HP-UX. Added features include shared
7988 library support, kernel threads and hardware watchpoints for 11.00,
7989 support for HP's ANSI C and C++ compilers, and a compatibility mode
7990 for xdb and dbx commands.
7994 HP's donation includes the new concept of catchpoints, which is a
7995 generalization of the old catch command. On HP-UX, it is now possible
7996 to catch exec, fork, and vfork, as well as library loading.
7998 This means that the existing catch command has changed; its first
7999 argument now specifies the type of catch to be set up. See the
8000 output of "help catch" for a list of catchpoint types.
8002 * Debugging across forks
8004 On HP-UX, you can choose which process to debug when a fork() happens
8009 HP has donated a curses-based terminal user interface (TUI). To get
8010 it, build with --enable-tui. Although this can be enabled for any
8011 configuration, at present it only works for native HP debugging.
8013 * GDB remote protocol additions
8015 A new protocol packet 'X' that writes binary data is now available.
8016 Default behavior is to try 'X', then drop back to 'M' if the stub
8017 fails to respond. The settable variable `remotebinarydownload'
8018 allows explicit control over the use of 'X'.
8020 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
8021 full 64-bit address. The command
8023 set remoteaddresssize 32
8025 can be used to revert to the old behaviour. For existing remote stubs
8026 the change should not be noticed, as the additional address information
8029 In order to assist in debugging stubs, you may use the maintenance
8030 command `packet' to send any text string to the stub. For instance,
8032 maint packet heythere
8034 sends the packet "$heythere#<checksum>". Note that it is very easy to
8035 disrupt a debugging session by sending the wrong packet at the wrong
8038 The compare-sections command allows you to compare section data on the
8039 target to what is in the executable file without uploading or
8040 downloading, by comparing CRC checksums.
8042 * Tracing can collect general expressions
8044 You may now collect general expressions at tracepoints. This requires
8045 further additions to the target-side stub; see tracepoint.c and
8046 doc/agentexpr.texi for further details.
8048 * mask-address variable for Mips
8050 For Mips targets, you may control the zeroing of the upper 32 bits of
8051 a 64-bit address by entering `set mask-address on'. This is mainly
8052 of interest to users of embedded R4xxx and R5xxx processors.
8054 * Higher serial baud rates
8056 GDB's serial code now allows you to specify baud rates 57600, 115200,
8057 230400, and 460800 baud. (Note that your host system may not be able
8058 to achieve all of these rates.)
8062 The i960 configuration now includes an initial implementation of a
8063 builtin simulator, contributed by Jim Wilson.
8066 *** Changes in GDB-4.17:
8068 * New native configurations
8070 Alpha GNU/Linux alpha*-*-linux*
8071 Unixware 2.x i[3456]86-unixware2*
8072 Irix 6.x mips*-sgi-irix6*
8073 PowerPC GNU/Linux powerpc-*-linux*
8074 PowerPC Solaris powerpcle-*-solaris*
8075 Sparc GNU/Linux sparc-*-linux*
8076 Motorola sysV68 R3V7.1 m68k-motorola-sysv
8080 Argonaut Risc Chip (ARC) arc-*-*
8081 Hitachi H8/300S h8300*-*-*
8082 Matsushita MN10200 w/simulator mn10200-*-*
8083 Matsushita MN10300 w/simulator mn10300-*-*
8084 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
8085 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
8086 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
8087 Mitsubishi D10V w/simulator d10v-*-*
8088 Mitsubishi M32R/D w/simulator m32r-*-elf*
8089 Tsqware Sparclet sparclet-*-*
8090 NEC V850 w/simulator v850-*-*
8092 * New debugging protocols
8094 ARM with RDI protocol arm*-*-*
8095 M68K with dBUG monitor m68*-*-{aout,coff,elf}
8096 DDB and LSI variants of PMON protocol mips*-*-*
8097 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
8098 PowerPC with SDS protocol powerpc{,le}-*-eabi
8099 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
8103 All configurations can now understand and use the DWARF 2 debugging
8104 format. The choice is automatic, if the symbol file contains DWARF 2
8109 GDB now includes basic Java language support. This support is
8110 only useful with Java compilers that produce native machine code.
8112 * solib-absolute-prefix and solib-search-path
8114 For SunOS and SVR4 shared libraries, you may now set the prefix for
8115 loading absolute shared library symbol files, and the search path for
8116 locating non-absolute shared library symbol files.
8118 * Live range splitting
8120 GDB can now effectively debug code for which GCC has performed live
8121 range splitting as part of its optimization. See gdb/doc/LRS for
8122 more details on the expected format of the stabs information.
8126 GDB's support for the GNU Hurd, including thread debugging, has been
8127 updated to work with current versions of the Hurd.
8131 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
8132 instruction set. ARM GDB automatically detects when Thumb
8133 instructions are in use, and adjusts disassembly and backtracing
8138 GDB's MIPS target configurations now handle the MIP16 16-bit
8143 GDB now includes support for overlays; if an executable has been
8144 linked such that multiple sections are based at the same address, GDB
8145 will decide which section to use for symbolic info. You can choose to
8146 control the decision manually, using overlay commands, or implement
8147 additional target-side support and use "overlay load-target" to bring
8148 in the overlay mapping. Do "help overlay" for more detail.
8152 The command "info symbol <address>" displays information about
8153 the symbol at the specified address.
8157 The standard remote protocol now includes an extension that allows
8158 asynchronous collection and display of trace data. This requires
8159 extensive support in the target-side debugging stub. Tracing mode
8160 includes a new interaction mode in GDB and new commands: see the
8161 file tracepoint.c for more details.
8165 Configurations for embedded MIPS now include a simulator contributed
8166 by Cygnus Solutions. The simulator supports the instruction sets
8167 of most MIPS variants.
8171 Sparc configurations may now include the ERC32 simulator contributed
8172 by the European Space Agency. The simulator is not built into
8173 Sparc targets by default; configure with --enable-sim to include it.
8177 For target configurations that may include multiple variants of a
8178 basic architecture (such as MIPS and SH), you may now set the
8179 architecture explicitly. "set arch" sets, "info arch" lists
8180 the possible architectures.
8182 *** Changes in GDB-4.16:
8184 * New native configurations
8186 Windows 95, x86 Windows NT i[345]86-*-cygwin32
8187 M68K NetBSD m68k-*-netbsd*
8188 PowerPC AIX 4.x powerpc-*-aix*
8189 PowerPC MacOS powerpc-*-macos*
8190 PowerPC Windows NT powerpcle-*-cygwin32
8191 RS/6000 AIX 4.x rs6000-*-aix4*
8195 ARM with RDP protocol arm-*-*
8196 I960 with MON960 i960-*-coff
8197 MIPS VxWorks mips*-*-vxworks*
8198 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
8199 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
8201 Matra Sparclet sparclet-*-*
8205 The powerpc-eabi configuration now includes the PSIM simulator,
8206 contributed by Andrew Cagney, with assistance from Mike Meissner.
8207 PSIM is a very elaborate model of the PowerPC, including not only
8208 basic instruction set execution, but also details of execution unit
8209 performance and I/O hardware. See sim/ppc/README for more details.
8213 GDB now works with Solaris 2.5.
8215 * Windows 95/NT native
8217 GDB will now work as a native debugger on Windows 95 and Windows NT.
8218 To build it from source, you must use the "gnu-win32" environment,
8219 which uses a DLL to emulate enough of Unix to run the GNU tools.
8220 Further information, binaries, and sources are available at
8221 ftp.cygnus.com, under pub/gnu-win32.
8223 * dont-repeat command
8225 If a user-defined command includes the command `dont-repeat', then the
8226 command will not be repeated if the user just types return. This is
8227 useful if the command is time-consuming to run, so that accidental
8228 extra keystrokes don't run the same command many times.
8230 * Send break instead of ^C
8232 The standard remote protocol now includes an option to send a break
8233 rather than a ^C to the target in order to interrupt it. By default,
8234 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
8236 * Remote protocol timeout
8238 The standard remote protocol includes a new variable `remotetimeout'
8239 that allows you to set the number of seconds before GDB gives up trying
8240 to read from the target. The default value is 2.
8242 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
8244 By default GDB will automatically keep track of objects as they are
8245 loaded and unloaded by the dynamic linker. By using the command `set
8246 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
8247 when shared library events occur, thus allowing you to set breakpoints
8248 in shared libraries which are explicitly loaded by the inferior.
8250 Note this feature does not work on hpux8. On hpux9 you must link
8251 /usr/lib/end.o into your program. This feature should work
8252 automatically on hpux10.
8254 * Irix 5.x hardware watchpoint support
8256 Irix 5 configurations now support the use of hardware watchpoints.
8258 * Mips protocol "SYN garbage limit"
8260 When debugging a Mips target using the `target mips' protocol, you
8261 may set the number of characters that GDB will ignore by setting
8262 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
8263 every character. The default value is 1050.
8265 * Recording and replaying remote debug sessions
8267 If you set `remotelogfile' to the name of a file, gdb will write to it
8268 a recording of a remote debug session. This recording may then be
8269 replayed back to gdb using "gdbreplay". See gdbserver/README for
8270 details. This is useful when you have a problem with GDB while doing
8271 remote debugging; you can make a recording of the session and send it
8272 to someone else, who can then recreate the problem.
8274 * Speedups for remote debugging
8276 GDB includes speedups for downloading and stepping MIPS systems using
8277 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
8278 and more efficient S-record downloading.
8280 * Memory use reductions and statistics collection
8282 GDB now uses less memory and reports statistics about memory usage.
8283 Try the `maint print statistics' command, for example.
8285 *** Changes in GDB-4.15:
8287 * Psymtabs for XCOFF
8289 The symbol reader for AIX GDB now uses partial symbol tables. This
8290 can greatly improve startup time, especially for large executables.
8292 * Remote targets use caching
8294 Remote targets now use a data cache to speed up communication with the
8295 remote side. The data cache could lead to incorrect results because
8296 it doesn't know about volatile variables, thus making it impossible to
8297 debug targets which use memory mapped I/O devices. `set remotecache
8298 off' turns the data cache off.
8300 * Remote targets may have threads
8302 The standard remote protocol now includes support for multiple threads
8303 in the target system, using new protocol commands 'H' and 'T'. See
8304 gdb/remote.c for details.
8308 If GDB is configured with `--enable-netrom', then it will include
8309 support for the NetROM ROM emulator from XLNT Designs. The NetROM
8310 acts as though it is a bank of ROM on the target board, but you can
8311 write into it over the network. GDB's support consists only of
8312 support for fast loading into the emulated ROM; to debug, you must use
8313 another protocol, such as standard remote protocol. The usual
8314 sequence is something like
8316 target nrom <netrom-hostname>
8318 target remote <netrom-hostname>:1235
8322 GDB now includes support for the Apple Macintosh, as a host only. It
8323 may be run as either an MPW tool or as a standalone application, and
8324 it can debug through the serial port. All the usual GDB commands are
8325 available, but to the target command, you must supply "serial" as the
8326 device type instead of "/dev/ttyXX". See mpw-README in the main
8327 directory for more information on how to build. The MPW configuration
8328 scripts */mpw-config.in support only a few targets, and only the
8329 mips-idt-ecoff target has been tested.
8333 GDB configuration now uses autoconf. This is not user-visible,
8334 but does simplify configuration and building.
8338 GDB now supports hpux10.
8340 *** Changes in GDB-4.14:
8342 * New native configurations
8344 x86 FreeBSD i[345]86-*-freebsd
8345 x86 NetBSD i[345]86-*-netbsd
8346 NS32k NetBSD ns32k-*-netbsd
8347 Sparc NetBSD sparc-*-netbsd
8351 A29K VxWorks a29k-*-vxworks
8352 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
8353 CPU32 EST-300 emulator m68*-*-est*
8354 PowerPC ELF powerpc-*-elf
8357 * Alpha OSF/1 support for procfs
8359 GDB now supports procfs under OSF/1-2.x and higher, which makes it
8360 possible to attach to running processes. As the mounting of the /proc
8361 filesystem is optional on the Alpha, GDB automatically determines
8362 the availability of /proc during startup. This can lead to problems
8363 if /proc is unmounted after GDB has been started.
8365 * Arguments to user-defined commands
8367 User commands may accept up to 10 arguments separated by whitespace.
8368 Arguments are accessed within the user command via $arg0..$arg9. A
8371 print $arg0 + $arg1 + $arg2
8373 To execute the command use:
8376 Defines the command "adder" which prints the sum of its three arguments.
8377 Note the arguments are text substitutions, so they may reference variables,
8378 use complex expressions, or even perform inferior function calls.
8380 * New `if' and `while' commands
8382 This makes it possible to write more sophisticated user-defined
8383 commands. Both commands take a single argument, which is the
8384 expression to evaluate, and must be followed by the commands to
8385 execute, one per line, if the expression is nonzero, the list being
8386 terminated by the word `end'. The `if' command list may include an
8387 `else' word, which causes the following commands to be executed only
8388 if the expression is zero.
8390 * Fortran source language mode
8392 GDB now includes partial support for Fortran 77. It will recognize
8393 Fortran programs and can evaluate a subset of Fortran expressions, but
8394 variables and functions may not be handled correctly. GDB will work
8395 with G77, but does not yet know much about symbols emitted by other
8398 * Better HPUX support
8400 Most debugging facilities now work on dynamic executables for HPPAs
8401 running hpux9 or later. You can attach to running dynamically linked
8402 processes, but by default the dynamic libraries will be read-only, so
8403 for instance you won't be able to put breakpoints in them. To change
8404 that behavior do the following before running the program:
8410 This will cause the libraries to be mapped private and read-write.
8411 To revert to the normal behavior, do this:
8417 You cannot set breakpoints or examine data in the library until after
8418 the library is loaded if the function/data symbols do not have
8421 GDB can now also read debug symbols produced by the HP C compiler on
8422 HPPAs (sorry, no C++, Fortran or 68k support).
8424 * Target byte order now dynamically selectable
8426 You can choose which byte order to use with a target system, via the
8427 commands "set endian big" and "set endian little", and you can see the
8428 current setting by using "show endian". You can also give the command
8429 "set endian auto", in which case GDB will use the byte order
8430 associated with the executable. Currently, only embedded MIPS
8431 configurations support dynamic selection of target byte order.
8433 * New DOS host serial code
8435 This version uses DPMI interrupts to handle buffered I/O, so you
8436 no longer need to run asynctsr when debugging boards connected to
8439 *** Changes in GDB-4.13:
8441 * New "complete" command
8443 This lists all the possible completions for the rest of the line, if it
8444 were to be given as a command itself. This is intended for use by emacs.
8446 * Trailing space optional in prompt
8448 "set prompt" no longer adds a space for you after the prompt you set. This
8449 allows you to set a prompt which ends in a space or one that does not.
8451 * Breakpoint hit counts
8453 "info break" now displays a count of the number of times the breakpoint
8454 has been hit. This is especially useful in conjunction with "ignore"; you
8455 can ignore a large number of breakpoint hits, look at the breakpoint info
8456 to see how many times the breakpoint was hit, then run again, ignoring one
8457 less than that number, and this will get you quickly to the last hit of
8460 * Ability to stop printing at NULL character
8462 "set print null-stop" will cause GDB to stop printing the characters of
8463 an array when the first NULL is encountered. This is useful when large
8464 arrays actually contain only short strings.
8466 * Shared library breakpoints
8468 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
8469 breakpoints in shared libraries before the executable is run.
8471 * Hardware watchpoints
8473 There is a new hardware breakpoint for the watch command for sparclite
8474 targets. See gdb/sparclite/hw_breakpoint.note.
8476 Hardware watchpoints are also now supported under GNU/Linux.
8480 Annotations have been added. These are for use with graphical interfaces,
8481 and are still experimental. Currently only gdba.el uses these.
8483 * Improved Irix 5 support
8485 GDB now works properly with Irix 5.2.
8487 * Improved HPPA support
8489 GDB now works properly with the latest GCC and GAS.
8491 * New native configurations
8493 Sequent PTX4 i[34]86-sequent-ptx4
8494 HPPA running OSF/1 hppa*-*-osf*
8495 Atari TT running SVR4 m68*-*-sysv4*
8496 RS/6000 LynxOS rs6000-*-lynxos*
8500 OS/9000 i[34]86-*-os9k
8501 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
8504 * Hitachi SH7000 and E7000-PC ICE support
8506 There is now support for communicating with the Hitachi E7000-PC ICE.
8507 This is available automatically when GDB is configured for the SH.
8511 As usual, a variety of small fixes and improvements, both generic
8512 and configuration-specific. See the ChangeLog for more detail.
8514 *** Changes in GDB-4.12:
8516 * Irix 5 is now supported
8520 GDB-4.12 on the HPPA has a number of changes which make it unable
8521 to debug the output from the currently released versions of GCC and
8522 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
8523 of GCC and GAS, versions of these tools designed to work with GDB-4.12
8524 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
8527 *** Changes in GDB-4.11:
8529 * User visible changes:
8533 The "set remotedebug" option is now consistent between the mips remote
8534 target, remote targets using the gdb-specific protocol, UDI (AMD's
8535 debug protocol for the 29k) and the 88k bug monitor. It is now an
8536 integer specifying a debug level (normally 0 or 1, but 2 means more
8537 debugging info for the mips target).
8539 * DEC Alpha native support
8541 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
8542 debug info, but GDB works fairly well with the DEC compiler and should
8543 work with a future GCC release. See the README file for a few
8544 Alpha-specific notes.
8546 * Preliminary thread implementation
8548 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
8550 * LynxOS native and target support for 386
8552 This release has been hosted on LynxOS 2.2, and also can be configured
8553 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
8556 * Improvements in C++ mangling/demangling.
8558 This release has much better g++ debugging, specifically in name
8559 mangling/demangling, virtual function calls, print virtual table,
8560 call methods, ...etc.
8562 *** Changes in GDB-4.10:
8564 * User visible changes:
8566 Remote debugging using the GDB-specific (`target remote') protocol now
8567 supports the `load' command. This is only useful if you have some
8568 other way of getting the stub to the target system, and you can put it
8569 somewhere in memory where it won't get clobbered by the download.
8571 Filename completion now works.
8573 When run under emacs mode, the "info line" command now causes the
8574 arrow to point to the line specified. Also, "info line" prints
8575 addresses in symbolic form (as well as hex).
8577 All vxworks based targets now support a user settable option, called
8578 vxworks-timeout. This option represents the number of seconds gdb
8579 should wait for responses to rpc's. You might want to use this if
8580 your vxworks target is, perhaps, a slow software simulator or happens
8581 to be on the far side of a thin network line.
8585 This release contains support for using a DEC alpha as a GDB host for
8586 cross debugging. Native alpha debugging is not supported yet.
8589 *** Changes in GDB-4.9:
8593 This is the first GDB release which is accompanied by a matching testsuite.
8594 The testsuite requires installation of dejagnu, which should be available
8595 via ftp from most sites that carry GNU software.
8599 'Cfront' style demangling has had its name changed to 'ARM' style, to
8600 emphasize that it was written from the specifications in the C++ Annotated
8601 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
8602 disclaimers, it still generated too much confusion with users attempting to
8603 use gdb with AT&T cfront.
8607 GDB now uses a standard remote interface to a simulator library.
8608 So far, the library contains simulators for the Zilog Z8001/2, the
8609 Hitachi H8/300, H8/500 and Super-H.
8611 * New targets supported
8613 H8/300 simulator h8300-hitachi-hms or h8300hms
8614 H8/500 simulator h8500-hitachi-hms or h8500hms
8615 SH simulator sh-hitachi-hms or sh
8616 Z8000 simulator z8k-zilog-none or z8ksim
8617 IDT MIPS board over serial line mips-idt-ecoff
8619 Cross-debugging to GO32 targets is supported. It requires a custom
8620 version of the i386-stub.c module which is integrated with the
8621 GO32 memory extender.
8623 * New remote protocols
8625 MIPS remote debugging protocol.
8627 * New source languages supported
8629 This version includes preliminary support for Chill, a Pascal like language
8630 used by telecommunications companies. Chill support is also being integrated
8631 into the GNU compiler, but we don't know when it will be publically available.
8634 *** Changes in GDB-4.8:
8636 * HP Precision Architecture supported
8638 GDB now supports HP PA-RISC machines running HPUX. A preliminary
8639 version of this support was available as a set of patches from the
8640 University of Utah. GDB does not support debugging of programs
8641 compiled with the HP compiler, because HP will not document their file
8642 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
8643 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
8645 Many problems in the preliminary version have been fixed.
8647 * Faster and better demangling
8649 We have improved template demangling and fixed numerous bugs in the GNU style
8650 demangler. It can now handle type modifiers such as `static' or `const'. Wide
8651 character types (wchar_t) are now supported. Demangling of each symbol is now
8652 only done once, and is cached when the symbol table for a file is read in.
8653 This results in a small increase in memory usage for C programs, a moderate
8654 increase in memory usage for C++ programs, and a fantastic speedup in
8657 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
8658 from the specifications in the Annotated Reference Manual, which AT&T's
8659 compiler does not actually implement.
8661 * G++ multiple inheritance compiler problem
8663 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
8664 inheritance lattices was reworked to properly discover ambiguities. We
8665 recently found an example which causes this new algorithm to fail in a
8666 very subtle way, producing bad debug information for those classes.
8667 The file 'gcc.patch' (in this directory) can be applied to gcc to
8668 circumvent the problem. A future GCC release will contain a complete
8671 The previous G++ debug info problem (mentioned below for the gdb-4.7
8672 release) is fixed in gcc version 2.3.2.
8674 * Improved configure script
8676 The `configure' script will now attempt to guess your system type if
8677 you don't supply a host system type. The old scheme of supplying a
8678 host system triplet is preferable over using this. All the magic is
8679 done in the new `config.guess' script. Examine it for details.
8681 We have also brought our configure script much more in line with the FSF's
8682 version. It now supports the --with-xxx options. In particular,
8683 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
8684 The resulting GDB will not be able to read arbitrary object file formats --
8685 only the format ``expected'' to be used on the configured target system.
8686 We hope to make this the default in a future release.
8688 * Documentation improvements
8690 There's new internal documentation on how to modify GDB, and how to
8691 produce clean changes to the code. We implore people to read it
8692 before submitting changes.
8694 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
8695 M4 macros. The new texinfo.tex is provided in this release. Pre-built
8696 `info' files are also provided. To build `info' files from scratch,
8697 you will need the latest `makeinfo' release, which will be available in
8698 a future texinfo-X.Y release.
8700 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
8701 We're not sure exactly which versions have this problem, but it has
8702 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
8703 or better. If that isn't possible, there is a patch in
8704 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
8705 around this problem.
8709 GDB now supports array constants that can be used in expressions typed in by
8710 the user. The syntax is `{element, element, ...}'. Ie: you can now type
8711 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
8714 The new directory `gdb/sparclite' contains a program that demonstrates
8715 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
8717 * New native hosts supported
8719 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
8720 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
8722 * New targets supported
8724 AMD 29k family via UDI a29k-amd-udi or udi29k
8726 * New file formats supported
8728 BFD now supports reading HP/PA-RISC executables (SOM file format?),
8729 HPUX core files, and SCO 3.2v2 core files.
8733 Attaching to processes now works again; thanks for the many bug reports.
8735 We have also stomped on a bunch of core dumps caused by
8736 printf_filtered("%s") problems.
8738 We eliminated a copyright problem on the rpc and ptrace header files
8739 for VxWorks, which was discovered at the last minute during the 4.7
8740 release. You should now be able to build a VxWorks GDB.
8742 You can now interrupt gdb while an attached process is running. This
8743 will cause the attached process to stop, and give control back to GDB.
8745 We fixed problems caused by using too many file descriptors
8746 for reading symbols from object files and libraries. This was
8747 especially a problem for programs that used many (~100) shared
8750 The `step' command now only enters a subroutine if there is line number
8751 information for the subroutine. Otherwise it acts like the `next'
8752 command. Previously, `step' would enter subroutines if there was
8753 any debugging information about the routine. This avoids problems
8754 when using `cc -g1' on MIPS machines.
8756 * Internal improvements
8758 GDB's internal interfaces have been improved to make it easier to support
8759 debugging of multiple languages in the future.
8761 GDB now uses a common structure for symbol information internally.
8762 Minimal symbols (derived from linkage symbols in object files), partial
8763 symbols (from a quick scan of debug information), and full symbols
8764 contain a common subset of information, making it easier to write
8765 shared code that handles any of them.
8767 * New command line options
8769 We now accept --silent as an alias for --quiet.
8773 The memory-mapped-malloc library is now licensed under the GNU Library
8774 General Public License.
8776 *** Changes in GDB-4.7:
8778 * Host/native/target split
8780 GDB has had some major internal surgery to untangle the support for
8781 hosts and remote targets. Now, when you configure GDB for a remote
8782 target, it will no longer load in all of the support for debugging
8783 local programs on the host. When fully completed and tested, this will
8784 ensure that arbitrary host/target combinations are possible.
8786 The primary conceptual shift is to separate the non-portable code in
8787 GDB into three categories. Host specific code is required any time GDB
8788 is compiled on that host, regardless of the target. Target specific
8789 code relates to the peculiarities of the target, but can be compiled on
8790 any host. Native specific code is everything else: it can only be
8791 built when the host and target are the same system. Child process
8792 handling and core file support are two common `native' examples.
8794 GDB's use of /proc for controlling Unix child processes is now cleaner.
8795 It has been split out into a single module under the `target_ops' vector,
8796 plus two native-dependent functions for each system that uses /proc.
8798 * New hosts supported
8800 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
8801 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
8802 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
8804 * New targets supported
8806 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
8807 68030 and CPU32 m68030-*-*, m68332-*-*
8809 * New native hosts supported
8811 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
8812 (386bsd is not well tested yet)
8813 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
8815 * New file formats supported
8817 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
8818 supports reading of `a.out.adobe' object files, which are an a.out
8819 format extended with minimal information about multiple sections.
8823 `show copying' is the same as the old `info copying'.
8824 `show warranty' is the same as `info warrantee'.
8825 These were renamed for consistency. The old commands continue to work.
8827 `info handle' is a new alias for `info signals'.
8829 You can now define pre-command hooks, which attach arbitrary command
8830 scripts to any command. The commands in the hook will be executed
8831 prior to the user's command. You can also create a hook which will be
8832 executed whenever the program stops. See gdb.texinfo.
8836 We now deal with Cfront style name mangling, and can even extract type
8837 info from mangled symbols. GDB can automatically figure out which
8838 symbol mangling style your C++ compiler uses.
8840 Calling of methods and virtual functions has been improved as well.
8844 The crash that occurred when debugging Sun Ansi-C compiled binaries is
8845 fixed. This was due to mishandling of the extra N_SO stabs output
8848 We also finally got Ultrix 4.2 running in house, and fixed core file
8849 support, with help from a dozen people on the net.
8851 John M. Farrell discovered that the reason that single-stepping was so
8852 slow on all of the Mips based platforms (primarily SGI and DEC) was
8853 that we were trying to demangle and lookup a symbol used for internal
8854 purposes on every instruction that was being stepped through. Changing
8855 the name of that symbol so that it couldn't be mistaken for a C++
8856 mangled symbol sped things up a great deal.
8858 Rich Pixley sped up symbol lookups in general by getting much smarter
8859 about when C++ symbol mangling is necessary. This should make symbol
8860 completion (TAB on the command line) much faster. It's not as fast as
8861 we'd like, but it's significantly faster than gdb-4.6.
8865 A new user controllable variable 'call_scratch_address' can
8866 specify the location of a scratch area to be used when GDB
8867 calls a function in the target. This is necessary because the
8868 usual method of putting the scratch area on the stack does not work
8869 in systems that have separate instruction and data spaces.
8871 We integrated changes to support the 29k UDI (Universal Debugger
8872 Interface), but discovered at the last minute that we didn't have all
8873 of the appropriate copyright paperwork. We are working with AMD to
8874 resolve this, and hope to have it available soon.
8878 We have sped up the remote serial line protocol, especially for targets
8879 with lots of registers. It now supports a new `expedited status' ('T')
8880 message which can be used in place of the existing 'S' status message.
8881 This allows the remote stub to send only the registers that GDB
8882 needs to make a quick decision about single-stepping or conditional
8883 breakpoints, eliminating the need to fetch the entire register set for
8884 each instruction being stepped through.
8886 The GDB remote serial protocol now implements a write-through cache for
8887 registers, only re-reading the registers if the target has run.
8889 There is also a new remote serial stub for SPARC processors. You can
8890 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
8891 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
8892 processor with a serial port.
8896 Configure.in files have become much easier to read and modify. A new
8897 `table driven' format makes it more obvious what configurations are
8898 supported, and what files each one uses.
8902 There is a new opcodes library which will eventually contain all of the
8903 disassembly routines and opcode tables. At present, it only contains
8904 Sparc and Z8000 routines. This will allow the assembler, debugger, and
8905 disassembler (binutils/objdump) to share these routines.
8907 The libiberty library is now copylefted under the GNU Library General
8908 Public License. This allows more liberal use, and was done so libg++
8909 can use it. This makes no difference to GDB, since the Library License
8910 grants all the rights from the General Public License.
8914 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
8915 reference to the stabs symbol info used by the debugger. It is (as far
8916 as we know) the only published document on this fascinating topic. We
8917 encourage you to read it, compare it to the stabs information on your
8918 system, and send improvements on the document in general (to
8919 bug-gdb@prep.ai.mit.edu).
8921 And, of course, many bugs have been fixed.
8924 *** Changes in GDB-4.6:
8926 * Better support for C++ function names
8928 GDB now accepts as input the "demangled form" of C++ overloaded function
8929 names and member function names, and can do command completion on such names
8930 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
8931 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
8932 Make use of command completion, it is your friend.
8934 GDB also now accepts a variety of C++ mangled symbol formats. They are
8935 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
8936 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
8937 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
8938 for the list of formats.
8940 * G++ symbol mangling problem
8942 Recent versions of gcc have a bug in how they emit debugging information for
8943 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
8944 directory) can be applied to gcc to fix the problem. Alternatively, if you
8945 can't fix gcc, you can #define GCC_MANGLE_BUG when compiling gdb/symtab.c. The
8946 usual symptom is difficulty with setting breakpoints on methods. GDB complains
8947 about the method being non-existent. (We believe that version 2.2.2 of GCC has
8950 * New 'maintenance' command
8952 All of the commands related to hacking GDB internals have been moved out of
8953 the main command set, and now live behind the 'maintenance' command. This
8954 can also be abbreviated as 'mt'. The following changes were made:
8956 dump-me -> maintenance dump-me
8957 info all-breakpoints -> maintenance info breakpoints
8958 printmsyms -> maintenance print msyms
8959 printobjfiles -> maintenance print objfiles
8960 printpsyms -> maintenance print psymbols
8961 printsyms -> maintenance print symbols
8963 The following commands are new:
8965 maintenance demangle Call internal GDB demangler routine to
8966 demangle a C++ link name and prints the result.
8967 maintenance print type Print a type chain for a given symbol
8969 * Change to .gdbinit file processing
8971 We now read the $HOME/.gdbinit file before processing the argv arguments
8972 (e.g. reading symbol files or core files). This allows global parameters to
8973 be set, which will apply during the symbol reading. The ./.gdbinit is still
8974 read after argv processing.
8976 * New hosts supported
8978 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
8980 GNU/Linux support i386-unknown-linux or linux
8982 We are also including code to support the HP/PA running BSD and HPUX. This
8983 is almost guaranteed not to work, as we didn't have time to test or build it
8984 for this release. We are including it so that the more adventurous (or
8985 masochistic) of you can play with it. We also had major problems with the
8986 fact that the compiler that we got from HP doesn't support the -g option.
8989 * New targets supported
8991 Hitachi H8/300 h8300-hitachi-hms or h8300hms
8993 * More smarts about finding #include files
8995 GDB now remembers the compilation directory for all include files, and for
8996 all files from which C is generated (like yacc and lex sources). This
8997 greatly improves GDB's ability to find yacc/lex sources, and include files,
8998 especially if you are debugging your program from a directory different from
8999 the one that contains your sources.
9001 We also fixed a bug which caused difficulty with listing and setting
9002 breakpoints in include files which contain C code. (In the past, you had to
9003 try twice in order to list an include file that you hadn't looked at before.)
9005 * Interesting infernals change
9007 GDB now deals with arbitrary numbers of sections, where the symbols for each
9008 section must be relocated relative to that section's landing place in the
9009 target's address space. This work was needed to support ELF with embedded
9010 stabs used by Solaris-2.0.
9012 * Bug fixes (of course!)
9014 There have been loads of fixes for the following things:
9015 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
9016 i960, stabs, DOS(GO32), procfs, etc...
9018 See the ChangeLog for details.
9020 *** Changes in GDB-4.5:
9022 * New machines supported (host and target)
9024 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
9026 SGI Irix-4.x mips-sgi-irix4 or iris4
9028 * New malloc package
9030 GDB now uses a new memory manager called mmalloc, based on gmalloc.
9031 Mmalloc is capable of handling multiple heaps of memory. It is also
9032 capable of saving a heap to a file, and then mapping it back in later.
9033 This can be used to greatly speedup the startup of GDB by using a
9034 pre-parsed symbol table which lives in a mmalloc managed heap. For
9035 more details, please read mmalloc/mmalloc.texi.
9039 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
9040 'help info proc' for details.
9042 * MIPS ecoff symbol table format
9044 The code that reads MIPS symbol table format is now supported on all hosts.
9045 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
9048 * File name changes for MS-DOS
9050 Many files in the config directories have been renamed to make it easier to
9051 support GDB on MS-DOSe systems (which have very restrictive file name
9052 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
9053 environment) is close to working but has some remaining problems. Note
9054 that debugging of DOS programs is not supported, due to limitations
9055 in the ``operating system'', but it can be used to host cross-debugging.
9057 * Cross byte order fixes
9059 Many fixes have been made to support cross debugging of Sparc and MIPS
9060 targets from hosts whose byte order differs.
9062 * New -mapped and -readnow options
9064 If memory-mapped files are available on your system through the 'mmap'
9065 system call, you can use the -mapped option on the `file' or
9066 `symbol-file' commands to cause GDB to write the symbols from your
9067 program into a reusable file. If the program you are debugging is
9068 called `/path/fred', the mapped symbol file will be `./fred.syms'.
9069 Future GDB debugging sessions will notice the presence of this file,
9070 and will quickly map in symbol information from it, rather than reading
9071 the symbol table from the executable program. Using the '-mapped'
9072 option in a GDB `file' or `symbol-file' command has the same effect as
9073 starting GDB with the '-mapped' command-line option.
9075 You can cause GDB to read the entire symbol table immediately by using
9076 the '-readnow' option with any of the commands that load symbol table
9077 information (or on the GDB command line). This makes the command
9078 slower, but makes future operations faster.
9080 The -mapped and -readnow options are typically combined in order to
9081 build a `fred.syms' file that contains complete symbol information.
9082 A simple GDB invocation to do nothing but build a `.syms' file for future
9085 gdb -batch -nx -mapped -readnow programname
9087 The `.syms' file is specific to the host machine on which GDB is run.
9088 It holds an exact image of GDB's internal symbol table. It cannot be
9089 shared across multiple host platforms.
9091 * longjmp() handling
9093 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
9094 siglongjmp() without losing control. This feature has not yet been ported to
9095 all systems. It currently works on many 386 platforms, all MIPS-based
9096 platforms (SGI, DECstation, etc), and Sun3/4.
9100 Preliminary work has been put in to support the new Solaris OS from Sun. At
9101 this time, it can control and debug processes, but it is not capable of
9106 As always, many many bug fixes. The major areas were with g++, and mipsread.
9107 People using the MIPS-based platforms should experience fewer mysterious
9108 crashes and trashed symbol tables.
9110 *** Changes in GDB-4.4:
9112 * New machines supported (host and target)
9114 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
9116 BSD Reno on Vax vax-dec-bsd
9117 Ultrix on Vax vax-dec-ultrix
9119 * New machines supported (target)
9121 AMD 29000 embedded, using EBMON a29k-none-none
9125 GDB continues to improve its handling of C++. `References' work better.
9126 The demangler has also been improved, and now deals with symbols mangled as
9127 per the Annotated C++ Reference Guide.
9129 GDB also now handles `stabs' symbol information embedded in MIPS
9130 `ecoff' symbol tables. Since the ecoff format was not easily
9131 extensible to handle new languages such as C++, this appeared to be a
9132 good way to put C++ debugging info into MIPS binaries. This option
9133 will be supported in the GNU C compiler, version 2, when it is
9136 * New features for SVR4
9138 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
9139 shared libraries. Debugging dynamically linked programs should present
9140 only minor differences from debugging statically linked programs.
9142 The `info proc' command will print out information about any process
9143 on an SVR4 system (including the one you are debugging). At the moment,
9144 it prints the address mappings of the process.
9146 If you bring up GDB on another SVR4 system, please send mail to
9147 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
9149 * Better dynamic linking support in SunOS
9151 Reading symbols from shared libraries which contain debugging symbols
9152 now works properly. However, there remain issues such as automatic
9153 skipping of `transfer vector' code during function calls, which
9154 make it harder to debug code in a shared library, than to debug the
9155 same code linked statically.
9159 GDB is now using the latest `getopt' routines from the FSF. This
9160 version accepts the -- prefix for options with long names. GDB will
9161 continue to accept the old forms (-option and +option) as well.
9162 Various single letter abbreviations for options have been explicity
9163 added to the option table so that they won't get overshadowed in the
9164 future by other options that begin with the same letter.
9168 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
9169 Many assorted bugs have been handled. Many more remain to be handled.
9170 See the various ChangeLog files (primarily in gdb and bfd) for details.
9173 *** Changes in GDB-4.3:
9175 * New machines supported (host and target)
9177 Amiga 3000 running Amix m68k-cbm-svr4 or amix
9178 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
9179 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
9181 * Almost SCO Unix support
9183 We had hoped to support:
9184 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
9185 (except for core file support), but we discovered very late in the release
9186 that it has problems with process groups that render gdb unusable. Sorry
9187 about that. I encourage people to fix it and post the fixes.
9189 * Preliminary ELF and DWARF support
9191 GDB can read ELF object files on System V Release 4, and can handle
9192 debugging records for C, in DWARF format, in ELF files. This support
9193 is preliminary. If you bring up GDB on another SVR4 system, please
9194 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
9199 GDB now uses the latest `readline' library. One user-visible change
9200 is that two tabs will list possible command completions, which previously
9201 required typing M-? (meta-question mark, or ESC ?).
9205 The `stepi' bug that many of you noticed has been squashed.
9206 Many bugs in C++ have been handled. Many more remain to be handled.
9207 See the various ChangeLog files (primarily in gdb and bfd) for details.
9209 * State of the MIPS world (in case you wondered):
9211 GDB can understand the symbol tables emitted by the compilers
9212 supplied by most vendors of MIPS-based machines, including DEC. These
9213 symbol tables are in a format that essentially nobody else uses.
9215 Some versions of gcc come with an assembler post-processor called
9216 mips-tfile. This program is required if you want to do source-level
9217 debugging of gcc-compiled programs. I believe FSF does not ship
9218 mips-tfile with gcc version 1, but it will eventually come with gcc
9221 Debugging of g++ output remains a problem. g++ version 1.xx does not
9222 really support it at all. (If you're lucky, you should be able to get
9223 line numbers and stack traces to work, but no parameters or local
9224 variables.) With some work it should be possible to improve the
9227 When gcc version 2 is released, you will have somewhat better luck.
9228 However, even then you will get confusing results for inheritance and
9231 We will eventually provide full debugging of g++ output on
9232 DECstations. This will probably involve some kind of stabs-in-ecoff
9233 encapulation, but the details have not been worked out yet.
9236 *** Changes in GDB-4.2:
9238 * Improved configuration
9240 Only one copy of `configure' exists now, and it is not self-modifying.
9241 Porting BFD is simpler.
9245 The `step' and `next' commands now only stop at the first instruction
9246 of a source line. This prevents the multiple stops that used to occur
9247 in switch statements, for-loops, etc. `Step' continues to stop if a
9248 function that has debugging information is called within the line.
9252 Lots of small bugs fixed. More remain.
9254 * New host supported (not target)
9256 Intel 386 PC clone running Mach i386-none-mach
9259 *** Changes in GDB-4.1:
9261 * Multiple source language support
9263 GDB now has internal scaffolding to handle several source languages.
9264 It determines the type of each source file from its filename extension,
9265 and will switch expression parsing and number formatting to match the
9266 language of the function in the currently selected stack frame.
9267 You can also specifically set the language to be used, with
9268 `set language c' or `set language modula-2'.
9272 GDB now has preliminary support for the GNU Modula-2 compiler,
9273 currently under development at the State University of New York at
9274 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
9275 continue through the fall of 1991 and into 1992.
9277 Other Modula-2 compilers are currently not supported, and attempting to
9278 debug programs compiled with them will likely result in an error as the
9279 symbol table is read. Feel free to work on it, though!
9281 There are hooks in GDB for strict type checking and range checking,
9282 in the `Modula-2 philosophy', but they do not currently work.
9286 GDB can now write to executable and core files (e.g. patch
9287 a variable's value). You must turn this switch on, specify
9288 the file ("exec foo" or "core foo"), *then* modify it, e.g.
9289 by assigning a new value to a variable. Modifications take
9292 * Automatic SunOS shared library reading
9294 When you run your program, GDB automatically determines where its
9295 shared libraries (if any) have been loaded, and reads their symbols.
9296 The `share' command is no longer needed. This also works when
9297 examining core files.
9301 You can specify the number of lines that the `list' command shows.
9304 * New machines supported (host and target)
9306 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
9307 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
9308 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
9310 * New hosts supported (not targets)
9312 IBM RT/PC: romp-ibm-aix or rtpc
9314 * New targets supported (not hosts)
9316 AMD 29000 embedded with COFF a29k-none-coff
9317 AMD 29000 embedded with a.out a29k-none-aout
9318 Ultracomputer remote kernel debug a29k-nyu-kern
9320 * New remote interfaces
9326 *** Changes in GDB-4.0:
9330 Wide output is wrapped at good places to make the output more readable.
9332 Gdb now supports cross-debugging from a host machine of one type to a
9333 target machine of another type. Communication with the target system
9334 is over serial lines. The ``target'' command handles connecting to the
9335 remote system; the ``load'' command will download a program into the
9336 remote system. Serial stubs for the m68k and i386 are provided. Gdb
9337 also supports debugging of realtime processes running under VxWorks,
9338 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
9339 stub on the target system.
9341 New CPUs supported include the AMD 29000 and Intel 960.
9343 GDB now reads object files and symbol tables via a ``binary file''
9344 library, which allows a single copy of GDB to debug programs of multiple
9345 object file types such as a.out and coff.
9347 There is now a GDB reference card in "doc/refcard.tex". (Make targets
9348 refcard.dvi and refcard.ps are available to format it).
9351 * Control-Variable user interface simplified
9353 All variables that control the operation of the debugger can be set
9354 by the ``set'' command, and displayed by the ``show'' command.
9356 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
9357 ``Show prompt'' produces the response:
9358 Gdb's prompt is new-gdb=>.
9360 What follows are the NEW set commands. The command ``help set'' will
9361 print a complete list of old and new set commands. ``help set FOO''
9362 will give a longer description of the variable FOO. ``show'' will show
9363 all of the variable descriptions and their current settings.
9365 confirm on/off: Enables warning questions for operations that are
9366 hard to recover from, e.g. rerunning the program while
9367 it is already running. Default is ON.
9369 editing on/off: Enables EMACS style command line editing
9370 of input. Previous lines can be recalled with
9371 control-P, the current line can be edited with control-B,
9372 you can search for commands with control-R, etc.
9375 history filename NAME: NAME is where the gdb command history
9376 will be stored. The default is .gdb_history,
9377 or the value of the environment variable
9380 history size N: The size, in commands, of the command history. The
9381 default is 256, or the value of the environment variable
9384 history save on/off: If this value is set to ON, the history file will
9385 be saved after exiting gdb. If set to OFF, the
9386 file will not be saved. The default is OFF.
9388 history expansion on/off: If this value is set to ON, then csh-like
9389 history expansion will be performed on
9390 command line input. The default is OFF.
9392 radix N: Sets the default radix for input and output. It can be set
9393 to 8, 10, or 16. Note that the argument to "radix" is interpreted
9394 in the current radix, so "set radix 10" is always a no-op.
9396 height N: This integer value is the number of lines on a page. Default
9397 is 24, the current `stty rows'' setting, or the ``li#''
9398 setting from the termcap entry matching the environment
9401 width N: This integer value is the number of characters on a line.
9402 Default is 80, the current `stty cols'' setting, or the ``co#''
9403 setting from the termcap entry matching the environment
9406 Note: ``set screensize'' is obsolete. Use ``set height'' and
9407 ``set width'' instead.
9409 print address on/off: Print memory addresses in various command displays,
9410 such as stack traces and structure values. Gdb looks
9411 more ``symbolic'' if you turn this off; it looks more
9412 ``machine level'' with it on. Default is ON.
9414 print array on/off: Prettyprint arrays. New convenient format! Default
9417 print demangle on/off: Print C++ symbols in "source" form if on,
9420 print asm-demangle on/off: Same, for assembler level printouts
9423 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
9426 * Support for Epoch Environment.
9428 The epoch environment is a version of Emacs v18 with windowing. One
9429 new command, ``inspect'', is identical to ``print'', except that if you
9430 are running in the epoch environment, the value is printed in its own
9434 * Support for Shared Libraries
9436 GDB can now debug programs and core files that use SunOS shared libraries.
9437 Symbols from a shared library cannot be referenced
9438 before the shared library has been linked with the program (this
9439 happens after you type ``run'' and before the function main() is entered).
9440 At any time after this linking (including when examining core files
9441 from dynamically linked programs), gdb reads the symbols from each
9442 shared library when you type the ``sharedlibrary'' command.
9443 It can be abbreviated ``share''.
9445 sharedlibrary REGEXP: Load shared object library symbols for files
9446 matching a unix regular expression. No argument
9447 indicates to load symbols for all shared libraries.
9449 info sharedlibrary: Status of loaded shared libraries.
9454 A watchpoint stops execution of a program whenever the value of an
9455 expression changes. Checking for this slows down execution
9456 tremendously whenever you are in the scope of the expression, but is
9457 quite useful for catching tough ``bit-spreader'' or pointer misuse
9458 problems. Some machines such as the 386 have hardware for doing this
9459 more quickly, and future versions of gdb will use this hardware.
9461 watch EXP: Set a watchpoint (breakpoint) for an expression.
9463 info watchpoints: Information about your watchpoints.
9465 delete N: Deletes watchpoint number N (same as breakpoints).
9466 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
9467 enable N: Re-enables watchpoint number N (same as breakpoints).
9470 * C++ multiple inheritance
9472 When used with a GCC version 2 compiler, GDB supports multiple inheritance
9475 * C++ exception handling
9477 Gdb now supports limited C++ exception handling. Besides the existing
9478 ability to breakpoint on an exception handler, gdb can breakpoint on
9479 the raising of an exception (before the stack is peeled back to the
9482 catch FOO: If there is a FOO exception handler in the dynamic scope,
9483 set a breakpoint to catch exceptions which may be raised there.
9484 Multiple exceptions (``catch foo bar baz'') may be caught.
9486 info catch: Lists all exceptions which may be caught in the
9487 current stack frame.
9490 * Minor command changes
9492 The command ``call func (arg, arg, ...)'' now acts like the print
9493 command, except it does not print or save a value if the function's result
9494 is void. This is similar to dbx usage.
9496 The ``up'' and ``down'' commands now always print the frame they end up
9497 at; ``up-silently'' and `down-silently'' can be used in scripts to change
9498 frames without printing.
9500 * New directory command
9502 'dir' now adds directories to the FRONT of the source search path.
9503 The path starts off empty. Source files that contain debug information
9504 about the directory in which they were compiled can be found even
9505 with an empty path; Sun CC and GCC include this information. If GDB can't
9506 find your source file in the current directory, type "dir .".
9508 * Configuring GDB for compilation
9510 For normal use, type ``./configure host''. See README or gdb.texinfo
9513 GDB now handles cross debugging. If you are remotely debugging between
9514 two different machines, type ``./configure host -target=targ''.
9515 Host is the machine where GDB will run; targ is the machine
9516 where the program that you are debugging will run.