1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.1
8 ** Argument Dependent Lookup (ADL)
10 In C++ ADL lookup directs function search to the namespaces of its
11 arguments even if the namespace has not been imported.
21 Here the compiler will search for `foo' in the namespace of 'b'
22 and find A::foo. GDB now supports this. This construct is commonly
23 used in the Standard Template Library for operators.
25 ** Improved User Defined Operator Support
27 In addition to member operators, GDB now supports lookup of operators
28 defined in a namespace and imported with a `using' directive, operators
29 defined in the global scope, operators imported implicitly from an
30 anonymous namespace, and the ADL operators mentioned in the previous
32 GDB now also supports proper overload resolution for all the previously
33 mentioned flavors of operators.
35 ** static const class members
37 Printing of static const class members that are initialized in the
38 class definition has been fixed.
40 * Windows Thread Information Block access.
42 On Windows targets, GDB now supports displaying the Windows Thread
43 Information Block (TIB) structure. This structure is visible either
44 by using the new command `info w32 thread-information-block' or, by
45 dereferencing the new convenience variable named `$_tlb', a
46 thread-specific pointer to the TIB. This feature is also supported
47 when remote debugging using GDBserver.
53 Return the address of the Windows Thread Information Block of a given thread.
57 In response to several of the tracepoint packets, the target may now
58 also respond with a number of intermediate `qRelocInsn' request
59 packets before the final result packet, to have GDB handle
60 relocating an instruction to execute at a different address. This
61 is particularly useful for stubs that support fast tracepoints. GDB
62 reports support for this feature in the qSupported packet.
64 * The source command now accepts a -s option to force searching for the
65 script in the source search path even if the script name specifies
68 * New features in the GDB remote stub, GDBserver
70 - GDBserver now support tracepoints (including fast tracepoints).
71 The feature is currently supported by the i386-linux and
72 amd64-linux builds. See the "Tracepoints support in gdbserver"
73 section in the manual for more information. GDBserver JIT
74 compiles the tracepoint's conditional agent expression bytecode
75 into native code whenever possible for low overhead dynamic
76 tracepoints conditionals. For such tracepoints, an expression
77 that examines program state is evaluated when the tracepoint is
78 reached, in order to determine whether to capture trace data. If
79 the condition is simple and false, processing the tracepoint
80 finishes very quickly and no data is gathered.
82 - GDBserver now supports x86_64 Windows 64-bit debugging.
84 * GDB now sends xmlRegisters= in qSupported packet to indicate that
85 it understands register description.
87 * The --batch flag now disables pagination and queries.
89 * X86 general purpose registers
91 GDB now supports reading/writing byte, word and double-word x86
92 general purpose registers directly. This means you can use, say,
93 $ah or $ax to refer, respectively, to the byte register AH and
94 16-bit word register AX that are actually portions of the 32-bit
95 register EAX or 64-bit register RAX.
97 * The `commands' command now accepts a range of breakpoints to modify.
98 A plain `commands' following a command that creates multiple
99 breakpoints affects all the breakpoints set by that command. This
100 applies to breakpoints set by `rbreak', and also applies when a
101 single `break' command creates multiple breakpoints (e.g.,
102 breakpoints on overloaded c++ functions).
104 * The `rbreak' command now accepts a filename specification as part of
105 its argument, limiting the functions selected by the regex to those
106 in the specified file.
108 * Support for remote debugging Windows and SymbianOS shared libraries
109 from Unix hosts has been improved. Non Windows GDB builds now can
110 understand target reported file names that follow MS-DOS based file
111 system semantics, such as file names that include drive letters and
112 use the backslash character as directory separator. This makes it
113 possible to transparently use the "set sysroot" and "set
114 solib-search-path" on Unix hosts to point as host copies of the
115 target's shared libraries. See the new command "set
116 target-file-system-kind" described below, and the "Commands to
117 specify files" section in the user manual for more information.
121 eval template, expressions...
122 Convert the values of one or more expressions under the control
123 of the string template to a command line, and call it.
125 set target-file-system-kind unix|dos-based|auto
126 show target-file-system-kind
127 Set or show the assumed file system kind for target reported file
130 save breakpoints <filename>
131 Save all current breakpoint definitions to a file suitable for use
132 in a later debugging session. To read the saved breakpoint
133 definitions, use the `source' command.
135 `save tracepoints' is a new alias for `save-tracepoints'. The latter
140 ** GDB now provides a new directory location, called the python directory,
141 where Python scripts written for GDB can be installed. The location
142 of that directory is <data-directory>/python, where <data-directory>
143 is the GDB data directory. For more details, see section `Scripting
144 GDB using Python' in the manual.
146 ** The GDB Python API now has access to breakpoints, symbols, symbol
147 tables, program spaces, inferiors, threads and frame's code blocks.
148 Additionally, GDB Parameters can now be created from the API, and
149 manipulated via set/show in the CLI.
151 ** New functions gdb.target_charset, gdb.target_wide_charset,
152 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
154 ** New exception gdb.GdbError.
156 ** Pretty-printers are now also looked up in the current program space.
158 ** Pretty-printers can now be individually enabled and disabled.
160 ** GDB now looks for names of Python scripts to auto-load in a
161 special section named `.debug_gdb_scripts', in addition to looking
162 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
164 * Tracepoint actions were unified with breakpoint commands. In particular,
165 there are no longer differences in "info break" output for breakpoints and
166 tracepoints and the "commands" command can be used for both tracepoints and
171 ARM Symbian arm*-*-symbianelf*
173 * D language support.
174 GDB now supports debugging programs written in the D programming
177 *** Changes in GDB 7.1
183 GDB now supports importing of namespaces in C++. This enables the
184 user to inspect variables from imported namespaces. Support for
185 namepace aliasing has also been added. So, if a namespace is
186 aliased in the current scope (e.g. namepace C=A; ) the user can
187 print variables using the alias (e.g. (gdb) print C::x).
191 All known bugs relating to the printing of virtual base class were
192 fixed. It is now possible to call overloaded static methods using a
197 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
198 and reinterpret_cast<> are now handled by the C++ expression parser.
202 Xilinx MicroBlaze microblaze-*-*
207 Xilinx MicroBlaze microblaze
210 * Multi-program debugging.
212 GDB now has support for multi-program (a.k.a. multi-executable or
213 multi-exec) debugging. This allows for debugging multiple inferiors
214 simultaneously each running a different program under the same GDB
215 session. See "Debugging Multiple Inferiors and Programs" in the
216 manual for more information. This implied some user visible changes
217 in the multi-inferior support. For example, "info inferiors" now
218 lists inferiors that are not running yet or that have exited
219 already. See also "New commands" and "New options" below.
221 * New tracing features
223 GDB's tracepoint facility now includes several new features:
225 ** Trace state variables
227 GDB tracepoints now include support for trace state variables, which
228 are variables managed by the target agent during a tracing
229 experiment. They are useful for tracepoints that trigger each
230 other, so for instance one tracepoint can count hits in a variable,
231 and then a second tracepoint has a condition that is true when the
232 count reaches a particular value. Trace state variables share the
233 $-syntax of GDB convenience variables, and can appear in both
234 tracepoint actions and condition expressions. Use the "tvariable"
235 command to create, and "info tvariables" to view; see "Trace State
236 Variables" in the manual for more detail.
240 GDB now includes an option for defining fast tracepoints, which
241 targets may implement more efficiently, such as by installing a jump
242 into the target agent rather than a trap instruction. The resulting
243 speedup can be by two orders of magnitude or more, although the
244 tradeoff is that some program locations on some target architectures
245 might not allow fast tracepoint installation, for instance if the
246 instruction to be replaced is shorter than the jump. To request a
247 fast tracepoint, use the "ftrace" command, with syntax identical to
248 the regular trace command.
250 ** Disconnected tracing
252 It is now possible to detach GDB from the target while it is running
253 a trace experiment, then reconnect later to see how the experiment
254 is going. In addition, a new variable disconnected-tracing lets you
255 tell the target agent whether to continue running a trace if the
256 connection is lost unexpectedly.
260 GDB now has the ability to save the trace buffer into a file, and
261 then use that file as a target, similarly to you can do with
262 corefiles. You can select trace frames, print data that was
263 collected in them, and use tstatus to display the state of the
264 tracing run at the moment that it was saved. To create a trace
265 file, use "tsave <filename>", and to use it, do "target tfile
268 ** Circular trace buffer
270 You can ask the target agent to handle the trace buffer as a
271 circular buffer, discarding the oldest trace frames to make room for
272 newer ones, by setting circular-trace-buffer to on. This feature may
273 not be available for all target agents.
278 The disassemble command, when invoked with two arguments, now requires
279 the arguments to be comma-separated.
282 The info variables command now displays variable definitions. Files
283 which only declare a variable are not shown.
286 The source command is now capable of sourcing Python scripts.
287 This feature is dependent on the debugger being build with Python
290 Related to this enhancement is also the introduction of a new command
291 "set script-extension" (see below).
293 * New commands (for set/show, see "New options" below)
295 record save [<FILENAME>]
296 Save a file (in core file format) containing the process record
297 execution log for replay debugging at a later time.
299 record restore <FILENAME>
300 Restore the process record execution log that was saved at an
301 earlier time, for replay debugging.
303 add-inferior [-copies <N>] [-exec <FILENAME>]
306 clone-inferior [-copies <N>] [ID]
307 Make a new inferior ready to execute the same program another
313 maint info program-spaces
314 List the program spaces loaded into GDB.
316 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
317 show remote interrupt-sequence
318 Allow the user to select one of ^C, a BREAK signal or BREAK-g
319 as the sequence to the remote target in order to interrupt the execution.
320 Ctrl-C is a default. Some system prefers BREAK which is high level of
321 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
322 Magic SysRq g. It is BREAK signal and character 'g'.
324 set remote interrupt-on-connect [on | off]
325 show remote interrupt-on-connect
326 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
327 remote target when gdb connects to it. This is needed when you debug
330 set remotebreak [on | off]
332 Deprecated. Use "set/show remote interrupt-sequence" instead.
334 tvariable $NAME [ = EXP ]
335 Create or modify a trace state variable.
338 List trace state variables and their values.
340 delete tvariable $NAME ...
341 Delete one or more trace state variables.
344 Evaluate the given expressions without collecting anything into the
345 trace buffer. (Valid in tracepoint actions only.)
347 ftrace FN / FILE:LINE / *ADDR
348 Define a fast tracepoint at the given function, line, or address.
350 * New expression syntax
352 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
353 GDB now parses 0b101010 identically with 42.
357 set follow-exec-mode new|same
358 show follow-exec-mode
359 Control whether GDB reuses the same inferior across an exec call or
360 creates a new one. This is useful to be able to restart the old
361 executable after the inferior having done an exec call.
363 set default-collect EXPR, ...
365 Define a list of expressions to be collected at each tracepoint.
366 This is a useful way to ensure essential items are not overlooked,
367 such as registers or a critical global variable.
369 set disconnected-tracing
370 show disconnected-tracing
371 If set to 1, the target is instructed to continue tracing if it
372 loses its connection to GDB. If 0, the target is to stop tracing
375 set circular-trace-buffer
376 show circular-trace-buffer
377 If set to on, the target is instructed to use a circular trace buffer
378 and discard the oldest trace frames instead of stopping the trace due
379 to a full trace buffer. If set to off, the trace stops when the buffer
380 fills up. Some targets may not support this.
382 set script-extension off|soft|strict
383 show script-extension
384 If set to "off", the debugger does not perform any script language
385 recognition, and all sourced files are assumed to be GDB scripts.
386 If set to "soft" (the default), files are sourced according to
387 filename extension, falling back to GDB scripts if the first
389 If set to "strict", files are sourced according to filename extension.
391 set ada trust-PAD-over-XVS on|off
392 show ada trust-PAD-over-XVS
393 If off, activate a workaround against a bug in the debugging information
394 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
395 the GCC sources for more information about the GNAT encoding and
396 PAD types in particular). It is always safe to set this option to
397 off, but this introduces a slight performance penalty. The default
400 * Python API Improvements
402 ** GDB provides the new class gdb.LazyString. This is useful in
403 some pretty-printing cases. The new method gdb.Value.lazy_string
404 provides a simple way to create objects of this type.
406 ** The fields returned by gdb.Type.fields now have an
407 `is_base_class' attribute.
409 ** The new method gdb.Type.range returns the range of an array type.
411 ** The new method gdb.parse_and_eval can be used to parse and
412 evaluate an expression.
417 Define a trace state variable.
420 Get the current value of a trace state variable.
423 Set desired tracing behavior upon disconnection.
426 Set the trace buffer to be linear or circular.
429 Get data about the tracepoints currently in use.
433 Process record now works correctly with hardware watchpoints.
435 Multiple bug fixes have been made to the mips-irix port, making it
436 much more reliable. In particular:
437 - Debugging threaded applications is now possible again. Previously,
438 GDB would hang while starting the program, or while waiting for
439 the program to stop at a breakpoint.
440 - Attaching to a running process no longer hangs.
441 - An error occurring while loading a core file has been fixed.
442 - Changing the value of the PC register now works again. This fixes
443 problems observed when using the "jump" command, or when calling
444 a function from GDB, or even when assigning a new value to $pc.
445 - With the "finish" and "return" commands, the return value for functions
446 returning a small array is now correctly printed.
447 - It is now possible to break on shared library code which gets executed
448 during a shared library init phase (code executed while executing
449 their .init section). Previously, the breakpoint would have no effect.
450 - GDB is now able to backtrace through the signal handler for
451 non-threaded programs.
453 PIE (Position Independent Executable) programs debugging is now supported.
454 This includes debugging execution of PIC (Position Independent Code) shared
455 libraries although for that, it should be possible to run such libraries as an
458 *** Changes in GDB 7.0
460 * GDB now has an interface for JIT compilation. Applications that
461 dynamically generate code can create symbol files in memory and register
462 them with GDB. For users, the feature should work transparently, and
463 for JIT developers, the interface is documented in the GDB manual in the
464 "JIT Compilation Interface" chapter.
466 * Tracepoints may now be conditional. The syntax is as for
467 breakpoints; either an "if" clause appended to the "trace" command,
468 or the "condition" command is available. GDB sends the condition to
469 the target for evaluation using the same bytecode format as is used
470 for tracepoint actions.
472 * "disassemble" command with a /r modifier, print the raw instructions
473 in hex as well as in symbolic form.
475 * Process record and replay
477 In a architecture environment that supports ``process record and
478 replay'', ``process record and replay'' target can record a log of
479 the process execution, and replay it with both forward and reverse
482 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
483 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
484 set execution-direction {forward|reverse}, for targets that support
487 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
488 feature is available with a native GDB running on kernel version
491 * GDB now has support for multi-byte and wide character sets on the
492 target. Strings whose character type is wchar_t, char16_t, or
493 char32_t are now correctly printed. GDB supports wide- and unicode-
494 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
495 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
496 `printf'. This feature requires iconv to work properly; if your
497 system does not have a working iconv, GDB can use GNU libiconv. See
498 the installation instructions for more information.
500 * GDB now supports automatic retrieval of shared library files from
501 remote targets. To use this feature, specify a system root that begins
502 with the `remote:' prefix, either via the `set sysroot' command or via
503 the `--with-sysroot' configure-time option.
505 * "info sharedlibrary" now takes an optional regex of libraries to show,
506 and it now reports if a shared library has no debugging information.
508 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
509 now complete on file names.
511 * When completing in expressions, gdb will attempt to limit
512 completions to allowable structure or union fields, where appropriate.
513 For instance, consider:
515 # struct example { int f1; double f2; };
516 # struct example variable;
519 If the user types TAB at the end of this command line, the available
520 completions will be "f1" and "f2".
522 * Inlined functions are now supported. They show up in backtraces, and
523 the "step", "next", and "finish" commands handle them automatically.
525 * GDB now supports the token-splicing (##) and stringification (#)
526 operators when expanding macros. It also supports variable-arity
529 * GDB now supports inspecting extra signal information, exported by
530 the new $_siginfo convenience variable. The feature is currently
531 implemented on linux ARM, i386 and amd64.
533 * GDB can now display the VFP floating point registers and NEON vector
534 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
535 can provide these registers (requires Linux 2.6.30 or later). Remote
536 and simulator targets may also provide them.
541 Search memory for a sequence of bytes.
544 Turn off `+'/`-' protocol acknowledgments to permit more efficient
545 operation over reliable transport links. Use of this packet is
546 controlled by the `set remote noack-packet' command.
549 Kill the process with the specified process ID. Use this in preference
550 to `k' when multiprocess protocol extensions are supported.
553 Obtains additional operating system information
557 Read or write additional signal information.
559 * Removed remote protocol undocumented extension
561 An undocumented extension to the remote protocol's `S' stop reply
562 packet that permited the stub to pass a process id was removed.
563 Remote servers should use the `T' stop reply packet instead.
565 * The "disassemble" command now supports an optional /m modifier to print mixed
568 * GDB now supports multiple function calling conventions according to the
569 DWARF-2 DW_AT_calling_convention function attribute.
571 * The SH target utilizes the aforementioned change to distinguish between gcc
572 and Renesas calling convention. It also adds the new CLI commands
573 `set/show sh calling-convention'.
575 * GDB can now read compressed debug sections, as produced by GNU gold
576 with the --compress-debug-sections=zlib flag.
578 * 64-bit core files are now supported on AIX.
580 * Thread switching is now supported on Tru64.
582 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
583 which will be allocated using malloc later in program execution.
585 * The qXfer:libraries:read remote procotol packet now allows passing a
586 list of section offsets.
588 * On GNU/Linux, GDB can now attach to stopped processes. Several race
589 conditions handling signals delivered during attach or thread creation
590 have also been fixed.
592 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
593 From the user's standpoint, all unqualified instances of True and False
594 are treated as the standard definitions, regardless of context.
596 * GDB now parses C++ symbol and type names more flexibly. For
599 template<typename T> class C { };
602 GDB will now correctly handle all of:
604 ptype C<char const *>
606 ptype C<const char *>
609 * New features in the GDB remote stub, gdbserver
611 - The "--wrapper" command-line argument tells gdbserver to use a
612 wrapper program to launch programs for debugging.
614 - On PowerPC and S/390 targets, it is now possible to use a single
615 gdbserver executable to debug both 32-bit and 64-bit programs.
616 (This requires gdbserver itself to be built as a 64-bit executable.)
618 - gdbserver uses the new noack protocol mode for TCP connections to
619 reduce communications latency, if also supported and enabled in GDB.
621 - Support for the sparc64-linux-gnu target is now included in
624 - The amd64-linux build of gdbserver now supports debugging both
625 32-bit and 64-bit programs.
627 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
628 now support hardware watchpoints, and will use them automatically
633 GDB now has support for scripting using Python. Whether this is
634 available is determined at configure time.
636 New GDB commands can now be written in Python.
638 * Ada tasking support
640 Ada tasks can now be inspected in GDB. The following commands have
644 Print the list of Ada tasks.
646 Print detailed information about task number N.
648 Print the task number of the current task.
650 Switch the context of debugging to task number N.
652 * Support for user-defined prefixed commands. The "define" command can
653 add new commands to existing prefixes, e.g. "target".
655 * Multi-inferior, multi-process debugging.
657 GDB now has generalized support for multi-inferior debugging. See
658 "Debugging Multiple Inferiors" in the manual for more information.
659 Although availability still depends on target support, the command
660 set is more uniform now. The GNU/Linux specific multi-forks support
661 has been migrated to this new framework. This implied some user
662 visible changes; see "New commands" and also "Removed commands"
665 * Target descriptions can now describe the target OS ABI. See the
666 "Target Description Format" section in the user manual for more
669 * Target descriptions can now describe "compatible" architectures
670 to indicate that the target can execute applications for a different
671 architecture in addition to those for the main target architecture.
672 See the "Target Description Format" section in the user manual for
675 * Multi-architecture debugging.
677 GDB now includes general supports for debugging applications on
678 hybrid systems that use more than one single processor architecture
679 at the same time. Each such hybrid architecture still requires
680 specific support to be added. The only hybrid architecture supported
681 in this version of GDB is the Cell Broadband Engine.
683 * GDB now supports integrated debugging of Cell/B.E. applications that
684 use both the PPU and SPU architectures. To enable support for hybrid
685 Cell/B.E. debugging, you need to configure GDB to support both the
686 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
687 --enable-targets configure option.
689 * Non-stop mode debugging.
691 For some targets, GDB now supports an optional mode of operation in
692 which you can examine stopped threads while other threads continue
693 to execute freely. This is referred to as non-stop mode, with the
694 old mode referred to as all-stop mode. See the "Non-Stop Mode"
695 section in the user manual for more information.
697 To be able to support remote non-stop debugging, a remote stub needs
698 to implement the non-stop mode remote protocol extensions, as
699 described in the "Remote Non-Stop" section of the user manual. The
700 GDB remote stub, gdbserver, has been adjusted to support these
701 extensions on linux targets.
703 * New commands (for set/show, see "New options" below)
705 catch syscall [NAME(S) | NUMBER(S)]
706 Catch system calls. Arguments, which should be names of system
707 calls or their numbers, mean catch only those syscalls. Without
708 arguments, every syscall will be caught. When the inferior issues
709 any of the specified syscalls, GDB will stop and announce the system
710 call, both when it is called and when its call returns. This
711 feature is currently available with a native GDB running on the
712 Linux Kernel, under the following architectures: x86, x86_64,
713 PowerPC and PowerPC64.
715 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
717 Search memory for a sequence of bytes.
719 maint set python print-stack
720 maint show python print-stack
721 Show a stack trace when an error is encountered in a Python script.
724 Invoke CODE by passing it to the Python interpreter.
729 These allow macros to be defined, undefined, and listed
733 Show operating system information about processes.
736 List the inferiors currently under GDB's control.
739 Switch focus to inferior number NUM.
742 Detach from inferior number NUM.
745 Kill inferior number NUM.
750 show spu stop-on-load
751 Control whether to stop for new SPE threads during Cell/B.E. debugging.
753 set spu auto-flush-cache
754 show spu auto-flush-cache
755 Control whether to automatically flush the software-managed cache
756 during Cell/B.E. debugging.
758 set sh calling-convention
759 show sh calling-convention
760 Control the calling convention used when calling SH target functions.
764 Control display of timestamps with GDB debugging output.
766 set disassemble-next-line
767 show disassemble-next-line
768 Control display of disassembled source lines or instructions when
771 set remote noack-packet
772 show remote noack-packet
773 Set/show the use of remote protocol QStartNoAckMode packet. See above
774 under "New remote packets."
776 set remote query-attached-packet
777 show remote query-attached-packet
778 Control use of remote protocol `qAttached' (query-attached) packet.
780 set remote read-siginfo-object
781 show remote read-siginfo-object
782 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
785 set remote write-siginfo-object
786 show remote write-siginfo-object
787 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
790 set remote reverse-continue
791 show remote reverse-continue
792 Control use of remote protocol 'bc' (reverse-continue) packet.
794 set remote reverse-step
795 show remote reverse-step
796 Control use of remote protocol 'bs' (reverse-step) packet.
798 set displaced-stepping
799 show displaced-stepping
800 Control displaced stepping mode. Displaced stepping is a way to
801 single-step over breakpoints without removing them from the debuggee.
802 Also known as "out-of-line single-stepping".
806 Control display of debugging info for displaced stepping.
808 maint set internal-error
809 maint show internal-error
810 Control what GDB does when an internal error is detected.
812 maint set internal-warning
813 maint show internal-warning
814 Control what GDB does when an internal warning is detected.
819 Use a wrapper program to launch programs for debugging.
821 set multiple-symbols (all|ask|cancel)
822 show multiple-symbols
823 The value of this variable can be changed to adjust the debugger behavior
824 when an expression or a breakpoint location contains an ambiguous symbol
825 name (an overloaded function name, for instance).
827 set breakpoint always-inserted
828 show breakpoint always-inserted
829 Keep breakpoints always inserted in the target, as opposed to inserting
830 them when resuming the target, and removing them when the target stops.
831 This option can improve debugger performance on slow remote targets.
833 set arm fallback-mode (arm|thumb|auto)
834 show arm fallback-mode
835 set arm force-mode (arm|thumb|auto)
837 These commands control how ARM GDB determines whether instructions
838 are ARM or Thumb. The default for both settings is auto, which uses
839 the current CPSR value for instructions without symbols; previous
840 versions of GDB behaved as if "set arm fallback-mode arm".
842 set disable-randomization
843 show disable-randomization
844 Standalone programs run with the virtual address space randomization enabled
845 by default on some platforms. This option keeps the addresses stable across
846 multiple debugging sessions.
850 Control whether other threads are stopped or not when some thread hits
855 Requests that asynchronous execution is enabled in the target, if available.
856 In this case, it's possible to resume target in the background, and interact
857 with GDB while the target is running. "show target-async" displays the
858 current state of asynchronous execution of the target.
860 set target-wide-charset
861 show target-wide-charset
862 The target-wide-charset is the name of the character set that GDB
863 uses when printing characters whose type is wchar_t.
865 set tcp auto-retry (on|off)
867 set tcp connect-timeout
868 show tcp connect-timeout
869 These commands allow GDB to retry failed TCP connections to a remote stub
870 with a specified timeout period; this is useful if the stub is launched
871 in parallel with GDB but may not be ready to accept connections immediately.
873 set libthread-db-search-path
874 show libthread-db-search-path
875 Control list of directories which GDB will search for appropriate
878 set schedule-multiple (on|off)
879 show schedule-multiple
880 Allow GDB to resume all threads of all processes or only threads of
885 Use more aggressive caching for accesses to the stack. This improves
886 performance of remote debugging (particularly backtraces) without
887 affecting correctness.
889 set interactive-mode (on|off|auto)
890 show interactive-mode
891 Control whether GDB runs in interactive mode (on) or not (off).
892 When in interactive mode, GDB waits for the user to answer all
893 queries. Otherwise, GDB does not wait and assumes the default
894 answer. When set to auto (the default), GDB determines which
895 mode to use based on the stdin settings.
900 For program forks, this is replaced by the new more generic `info
901 inferiors' command. To list checkpoints, you can still use the
902 `info checkpoints' command, which was an alias for the `info forks'
906 Replaced by the new `inferior' command. To switch between
907 checkpoints, you can still use the `restart' command, which was an
908 alias for the `fork' command.
911 This is removed, since some targets don't have a notion of
912 processes. To switch between processes, you can still use the
913 `inferior' command using GDB's own inferior number.
916 For program forks, this is replaced by the new more generic `kill
917 inferior' command. To delete a checkpoint, you can still use the
918 `delete checkpoint' command, which was an alias for the `delete
922 For program forks, this is replaced by the new more generic `detach
923 inferior' command. To detach a checkpoint, you can still use the
924 `detach checkpoint' command, which was an alias for the `detach
927 * New native configurations
929 x86/x86_64 Darwin i[34567]86-*-darwin*
931 x86_64 MinGW x86_64-*-mingw*
935 Lattice Mico32 lm32-*
936 x86 DICOS i[34567]86-*-dicos*
937 x86_64 DICOS x86_64-*-dicos*
940 * The GDB remote stub, gdbserver, now supports x86 Windows CE
941 (mingw32ce) debugging.
947 These commands were actually not implemented on any target.
949 *** Changes in GDB 6.8
951 * New native configurations
953 NetBSD/hppa hppa*-*netbsd*
954 Xtensa GNU/Linux xtensa*-*-linux*
958 NetBSD/hppa hppa*-*-netbsd*
959 Xtensa GNU/Lunux xtensa*-*-linux*
961 * Change in command line behavior -- corefiles vs. process ids.
963 When the '-p NUMBER' or '--pid NUMBER' options are used, and
964 attaching to process NUMBER fails, GDB no longer attempts to open a
965 core file named NUMBER. Attaching to a program using the -c option
966 is no longer supported. Instead, use the '-p' or '--pid' options.
968 * GDB can now be built as a native debugger for debugging Windows x86
969 (mingw32) Portable Executable (PE) programs.
971 * Pending breakpoints no longer change their number when their address
974 * GDB now supports breakpoints with multiple locations,
975 including breakpoints on C++ constructors, inside C++ templates,
976 and in inlined functions.
978 * GDB's ability to debug optimized code has been improved. GDB more
979 accurately identifies function bodies and lexical blocks that occupy
980 more than one contiguous range of addresses.
982 * Target descriptions can now describe registers for PowerPC.
984 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
985 registers on PowerPC targets.
987 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
988 targets even when the libthread_db library is not available.
990 * The GDB remote stub, gdbserver, now supports the new file transfer
991 commands (remote put, remote get, and remote delete).
993 * The GDB remote stub, gdbserver, now supports run and attach in
994 extended-remote mode.
996 * hppa*64*-*-hpux11* target broken
997 The debugger is unable to start a program and fails with the following
998 error: "Error trying to get information about dynamic linker".
999 The gdb-6.7 release is also affected.
1001 * GDB now supports the --enable-targets= configure option to allow
1002 building a single GDB executable that supports multiple remote
1003 target architectures.
1005 * GDB now supports debugging C and C++ programs which use the
1006 Decimal Floating Point extension. In addition, the PowerPC target
1007 now has a set of pseudo-registers to inspect decimal float values
1008 stored in two consecutive float registers.
1010 * The -break-insert MI command can optionally create pending
1013 * Improved support for debugging Ada
1014 Many improvements to the Ada language support have been made. These
1016 - Better support for Ada2005 interface types
1017 - Improved handling of arrays and slices in general
1018 - Better support for Taft-amendment types
1019 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1021 - Improved command completion in Ada
1024 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1029 set print frame-arguments (all|scalars|none)
1030 show print frame-arguments
1031 The value of this variable can be changed to control which argument
1032 values should be printed by the debugger when displaying a frame.
1037 Transfer files to and from a remote target, and delete remote files.
1044 Transfer files to and from a remote target, and delete remote files.
1046 * New remote packets
1053 Open, close, read, write, and delete files on the remote system.
1056 Attach to an existing process on the remote system, in extended-remote
1060 Run a new process on the remote system, in extended-remote mode.
1062 *** Changes in GDB 6.7
1064 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1065 bfd, libiberty and opcodes, as revealed by static analysis donated by
1066 Coverity, Inc. (http://scan.coverity.com).
1068 * When looking up multiply-defined global symbols, GDB will now prefer the
1069 symbol definition in the current shared library if it was built using the
1070 -Bsymbolic linker option.
1072 * When the Text User Interface (TUI) is not configured, GDB will now
1073 recognize the -tui command-line option and print a message that the TUI
1076 * The GDB remote stub, gdbserver, now has lower overhead for high
1077 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1079 * GDB for MIPS targets now autodetects whether a remote target provides
1080 32-bit or 64-bit register values.
1082 * Support for C++ member pointers has been improved.
1084 * GDB now understands XML target descriptions, which specify the
1085 target's overall architecture. GDB can read a description from
1086 a local file or over the remote serial protocol.
1088 * Vectors of single-byte data use a new integer type which is not
1089 automatically displayed as character or string data.
1091 * The /s format now works with the print command. It displays
1092 arrays of single-byte integers and pointers to single-byte integers
1095 * Target descriptions can now describe target-specific registers,
1096 for architectures which have implemented the support (currently
1097 only ARM, M68K, and MIPS).
1099 * GDB and the GDB remote stub, gdbserver, now support the XScale
1102 * The GDB remote stub, gdbserver, has been updated to support
1103 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1104 has been rewritten to use the standard GDB remote protocol.
1106 * GDB can now step into C++ functions which are called through thunks.
1108 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1110 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1111 layout. It also supports a TextSeg= and DataSeg= response when only
1112 segment base addresses (rather than offsets) are available.
1114 * The /i format now outputs any trailing branch delay slot instructions
1115 immediately following the last instruction within the count specified.
1117 * The GDB remote protocol "T" stop reply packet now supports a
1118 "library" response. Combined with the new "qXfer:libraries:read"
1119 packet, this response allows GDB to debug shared libraries on targets
1120 where the operating system manages the list of loaded libraries (e.g.
1121 Windows and SymbianOS).
1123 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1124 (DLLs) on Windows and Windows CE targets.
1126 * GDB now supports a faster verification that a .debug file matches its binary
1127 according to its build-id signature, if the signature is present.
1133 Enable or disable hardware flow control (RTS/CTS) on the serial port
1134 when debugging using remote targets.
1136 set mem inaccessible-by-default
1137 show mem inaccessible-by-default
1138 If the target supplies a memory map, for instance via the remote
1139 protocol's "qXfer:memory-map:read" packet, setting this variable
1140 prevents GDB from accessing memory outside the memory map. This
1141 is useful for targets with memory mapped registers or which react
1142 badly to accesses of unmapped address space.
1144 set breakpoint auto-hw
1145 show breakpoint auto-hw
1146 If the target supplies a memory map, for instance via the remote
1147 protocol's "qXfer:memory-map:read" packet, setting this variable
1148 lets GDB use hardware breakpoints automatically for memory regions
1149 where it can not use software breakpoints. This covers both the
1150 "break" command and internal breakpoints used for other commands
1151 including "next" and "finish".
1154 catch exception unhandled
1155 Stop the program execution when Ada exceptions are raised.
1158 Stop the program execution when an Ada assertion failed.
1162 Set an alternate system root for target files. This is a more
1163 general version of "set solib-absolute-prefix", which is now
1164 an alias to "set sysroot".
1167 Provide extended SPU facility status information. This set of
1168 commands is available only when debugging the Cell/B.E. SPU
1171 * New native configurations
1173 OpenBSD/sh sh*-*openbsd*
1176 unset tdesc filename
1178 Use the specified local file as an XML target description, and do
1179 not query the target for its built-in description.
1183 OpenBSD/sh sh*-*-openbsd*
1184 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1185 Toshiba Media Processor mep-elf
1187 * New remote packets
1190 Ignore the specified signals; pass them directly to the debugged program
1191 without stopping other threads or reporting them to GDB.
1193 qXfer:features:read:
1194 Read an XML target description from the target, which describes its
1199 Read or write contents of an spufs file on the target system. These
1200 packets are available only on the Cell/B.E. SPU architecture.
1202 qXfer:libraries:read:
1203 Report the loaded shared libraries. Combined with new "T" packet
1204 response, this packet allows GDB to debug shared libraries on
1205 targets where the operating system manages the list of loaded
1206 libraries (e.g. Windows and SymbianOS).
1210 Support for these obsolete configurations has been removed.
1218 i[34567]86-*-lynxos*
1219 i[34567]86-*-netware*
1220 i[34567]86-*-sco3.2v5*
1221 i[34567]86-*-sco3.2v4*
1223 i[34567]86-*-sysv4.2*
1226 i[34567]86-*-unixware2*
1227 i[34567]86-*-unixware*
1236 * Other removed features
1243 Various m68k-only ROM monitors.
1250 Various Renesas ROM monitors and debugging interfaces for SH and
1255 Support for a Macraigor serial interface to on-chip debugging.
1256 GDB does not directly support the newer parallel or USB
1261 A debug information format. The predecessor to DWARF 2 and
1262 DWARF 3, which are still supported.
1264 Support for the HP aCC compiler on HP-UX/PA-RISC
1266 SOM-encapsulated symbolic debugging information, automatic
1267 invocation of pxdb, and the aCC custom C++ ABI. This does not
1268 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1269 with aCC can still be debugged on an assembly level.
1271 MIPS ".pdr" sections
1273 A MIPS-specific format used to describe stack frame layout
1274 in debugging information.
1278 GDB could work with an older version of Guile to debug
1279 the interpreter and Scheme programs running in it.
1281 set mips stack-arg-size
1282 set mips saved-gpreg-size
1284 Use "set mips abi" to control parameter passing for MIPS.
1286 *** Changes in GDB 6.6
1291 Cell Broadband Engine SPU spu-elf
1293 * GDB can now be configured as a cross-debugger targeting native Windows
1294 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1295 running on a Windows system over TCP/IP to debug Windows programs.
1297 * The GDB remote stub, gdbserver, has been updated to support Windows and
1298 Cygwin debugging. Both single-threaded and multi-threaded programs are
1301 * The "set trust-readonly-sections" command works again. This command was
1302 broken in GDB 6.3, 6.4, and 6.5.
1304 * The "load" command now supports writing to flash memory, if the remote
1305 stub provides the required support.
1307 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1308 longer requires symbolic debug information (e.g. DWARF-2).
1313 unset substitute-path
1314 show substitute-path
1315 Manage a list of substitution rules that GDB uses to rewrite the name
1316 of the directories where the sources are located. This can be useful
1317 for instance when the sources were moved to a different location
1318 between compilation and debugging.
1322 Print each CLI command as it is executed. Each command is prefixed with
1323 a number of `+' symbols representing the nesting depth.
1324 The source command now has a `-v' option to enable the same feature.
1328 The ARM Demon monitor support (RDP protocol, "target rdp").
1330 Kernel Object Display, an embedded debugging feature which only worked with
1331 an obsolete version of Cisco IOS.
1333 The 'set download-write-size' and 'show download-write-size' commands.
1335 * New remote packets
1338 Tell a stub about GDB client features, and request remote target features.
1339 The first feature implemented is PacketSize, which allows the target to
1340 specify the size of packets it can handle - to minimize the number of
1341 packets required and improve performance when connected to a remote
1345 Fetch an OS auxilliary vector from the remote stub. This packet is a
1346 more efficient replacement for qPart:auxv:read.
1348 qXfer:memory-map:read:
1349 Fetch a memory map from the remote stub, including information about
1350 RAM, ROM, and flash memory devices.
1355 Erase and program a flash memory device.
1357 * Removed remote packets
1360 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1361 used it, and only gdbserver implemented it.
1363 *** Changes in GDB 6.5
1367 Renesas M32C/M16C m32c-elf
1369 Morpho Technologies ms1 ms1-elf
1373 init-if-undefined Initialize a convenience variable, but
1374 only if it doesn't already have a value.
1376 The following commands are presently only implemented for native GNU/Linux:
1378 checkpoint Save a snapshot of the program state.
1380 restart <n> Return the program state to a
1381 previously saved state.
1383 info checkpoints List currently saved checkpoints.
1385 delete-checkpoint <n> Delete a previously saved checkpoint.
1387 set|show detach-on-fork Tell gdb whether to detach from a newly
1388 forked process, or to keep debugging it.
1390 info forks List forks of the user program that
1391 are available to be debugged.
1393 fork <n> Switch to debugging one of several
1394 forks of the user program that are
1395 available to be debugged.
1397 delete-fork <n> Delete a fork from the list of forks
1398 that are available to be debugged (and
1399 kill the forked process).
1401 detach-fork <n> Delete a fork from the list of forks
1402 that are available to be debugged (and
1403 allow the process to continue).
1407 Morpho Technologies ms2 ms1-elf
1409 * Improved Windows host support
1411 GDB now builds as a cross debugger hosted on i686-mingw32, including
1412 native console support, and remote communications using either
1413 network sockets or serial ports.
1415 * Improved Modula-2 language support
1417 GDB can now print most types in the Modula-2 syntax. This includes:
1418 basic types, set types, record types, enumerated types, range types,
1419 pointer types and ARRAY types. Procedure var parameters are correctly
1420 printed and hexadecimal addresses and character constants are also
1421 written in the Modula-2 syntax. Best results can be obtained by using
1422 GNU Modula-2 together with the -gdwarf-2 command line option.
1426 The ARM rdi-share module.
1428 The Netware NLM debug server.
1430 *** Changes in GDB 6.4
1432 * New native configurations
1434 OpenBSD/arm arm*-*-openbsd*
1435 OpenBSD/mips64 mips64-*-openbsd*
1439 Morpho Technologies ms1 ms1-elf
1441 * New command line options
1443 --batch-silent As for --batch, but totally silent.
1444 --return-child-result The debugger will exist with the same value
1445 the child (debugged) program exited with.
1446 --eval-command COMMAND, -ex COMMAND
1447 Execute a single GDB CLI command. This may be
1448 specified multiple times and in conjunction
1449 with the --command (-x) option.
1451 * Deprecated commands removed
1453 The following commands, that were deprecated in 2000, have been
1457 set|show arm disassembly-flavor set|show arm disassembler
1458 othernames set arm disassembler
1459 set|show remotedebug set|show debug remote
1460 set|show archdebug set|show debug arch
1461 set|show eventdebug set|show debug event
1464 * New BSD user-level threads support
1466 It is now possible to debug programs using the user-level threads
1467 library on OpenBSD and FreeBSD. Currently supported (target)
1470 FreeBSD/amd64 x86_64-*-freebsd*
1471 FreeBSD/i386 i386-*-freebsd*
1472 OpenBSD/i386 i386-*-openbsd*
1474 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1475 are not yet supported.
1477 * New support for Matsushita MN10300 w/sim added
1478 (Work in progress). mn10300-elf.
1480 * REMOVED configurations and files
1482 VxWorks and the XDR protocol *-*-vxworks
1483 Motorola MCORE mcore-*-*
1484 National Semiconductor NS32000 ns32k-*-*
1486 * New "set print array-indexes" command
1488 After turning this setting "on", GDB prints the index of each element
1489 when displaying arrays. The default is "off" to preserve the previous
1492 * VAX floating point support
1494 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1496 * User-defined command support
1498 In addition to using $arg0..$arg9 for argument passing, it is now possible
1499 to use $argc to determine now many arguments have been passed. See the
1500 section on user-defined commands in the user manual for more information.
1502 *** Changes in GDB 6.3:
1504 * New command line option
1506 GDB now accepts -l followed by a number to set the timeout for remote
1509 * GDB works with GCC -feliminate-dwarf2-dups
1511 GDB now supports a more compact representation of DWARF-2 debug
1512 information using DW_FORM_ref_addr references. These are produced
1513 by GCC with the option -feliminate-dwarf2-dups and also by some
1514 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1515 to use -feliminate-dwarf2-dups.
1517 * Internationalization
1519 When supported by the host system, GDB will be built with
1520 internationalization (libintl). The task of marking up the sources is
1521 continued, we're looking forward to our first translation.
1525 Initial support for debugging programs compiled with the GNAT
1526 implementation of the Ada programming language has been integrated
1527 into GDB. In this release, support is limited to expression evaluation.
1529 * New native configurations
1531 GNU/Linux/m32r m32r-*-linux-gnu
1535 GDB's remote protocol now includes support for the 'p' packet. This
1536 packet is used to fetch individual registers from a remote inferior.
1538 * END-OF-LIFE registers[] compatibility module
1540 GDB's internal register infrastructure has been completely rewritten.
1541 The new infrastructure making possible the implementation of key new
1542 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1545 GDB 6.3 will be the last release to include the the registers[]
1546 compatibility module that allowed out-of-date configurations to
1547 continue to work. This change directly impacts the following
1557 powerpc bdm protocol
1559 Unless there is activity to revive these configurations, they will be
1560 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1562 * OBSOLETE configurations and files
1564 Configurations that have been declared obsolete in this release have
1565 been commented out. Unless there is activity to revive these
1566 configurations, the next release of GDB will have their sources
1567 permanently REMOVED.
1576 *** Changes in GDB 6.2.1:
1578 * MIPS `break main; run' gave an heuristic-fence-post warning
1580 When attempting to run even a simple program, a warning about
1581 heuristic-fence-post being hit would be reported. This problem has
1584 * MIPS IRIX 'long double' crashed GDB
1586 When examining a long double variable, GDB would get a segmentation
1587 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1588 IRIX long double values).
1592 A bug in the VAX stack code was causing problems with the "next"
1593 command. This problem has been fixed.
1595 *** Changes in GDB 6.2:
1597 * Fix for ``many threads''
1599 On GNU/Linux systems that use the NPTL threads library, a program
1600 rapidly creating and deleting threads would confuse GDB leading to the
1603 ptrace: No such process.
1604 thread_db_get_info: cannot get thread info: generic error
1606 This problem has been fixed.
1608 * "-async" and "-noasync" options removed.
1610 Support for the broken "-noasync" option has been removed (it caused
1613 * New ``start'' command.
1615 This command runs the program until the begining of the main procedure.
1617 * New BSD Kernel Data Access Library (libkvm) interface
1619 Using ``target kvm'' it is now possible to debug kernel core dumps and
1620 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1621 platforms. Currently supported (native-only) configurations are:
1623 FreeBSD/amd64 x86_64-*-freebsd*
1624 FreeBSD/i386 i?86-*-freebsd*
1625 NetBSD/i386 i?86-*-netbsd*
1626 NetBSD/m68k m68*-*-netbsd*
1627 NetBSD/sparc sparc-*-netbsd*
1628 OpenBSD/amd64 x86_64-*-openbsd*
1629 OpenBSD/i386 i?86-*-openbsd*
1630 OpenBSD/m68k m68*-openbsd*
1631 OpenBSD/sparc sparc-*-openbsd*
1633 * Signal trampoline code overhauled
1635 Many generic problems with GDB's signal handling code have been fixed.
1636 These include: backtraces through non-contiguous stacks; recognition
1637 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1638 call; backtrace through a signal trampoline; step into and out of
1639 signal handlers; and single-stepping in the signal trampoline.
1641 Please note that kernel bugs are a limiting factor here. These
1642 features have been shown to work on an s390 GNU/Linux system that
1643 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1645 * Cygwin support for DWARF 2 added.
1647 * New native configurations
1649 GNU/Linux/hppa hppa*-*-linux*
1650 OpenBSD/hppa hppa*-*-openbsd*
1651 OpenBSD/m68k m68*-*-openbsd*
1652 OpenBSD/m88k m88*-*-openbsd*
1653 OpenBSD/powerpc powerpc-*-openbsd*
1654 NetBSD/vax vax-*-netbsd*
1655 OpenBSD/vax vax-*-openbsd*
1657 * END-OF-LIFE frame compatibility module
1659 GDB's internal frame infrastructure has been completely rewritten.
1660 The new infrastructure making it possible to support key new features
1661 including DWARF 2 Call Frame Information. To aid in the task of
1662 migrating old configurations to this new infrastructure, a
1663 compatibility module, that allowed old configurations to continue to
1664 work, was also included.
1666 GDB 6.2 will be the last release to include this frame compatibility
1667 module. This change directly impacts the following configurations:
1677 Unless there is activity to revive these configurations, they will be
1678 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1680 * REMOVED configurations and files
1682 Sun 3, running SunOS 3 m68*-*-sunos3*
1683 Sun 3, running SunOS 4 m68*-*-sunos4*
1684 Sun 2, running SunOS 3 m68000-*-sunos3*
1685 Sun 2, running SunOS 4 m68000-*-sunos4*
1686 Motorola 680x0 running LynxOS m68*-*-lynxos*
1687 AT&T 3b1/Unix pc m68*-att-*
1688 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1689 decstation mips-dec-* mips-little-*
1690 riscos mips-*-riscos* mips-*-sysv*
1691 sonymips mips-sony-*
1692 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1694 *** Changes in GDB 6.1.1:
1696 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1698 The TUI (Text-mode User Interface) is now built as part of a default
1699 GDB configuration. It is enabled by either selecting the TUI with the
1700 command line option "-i=tui" or by running the separate "gdbtui"
1701 program. For more information on the TUI, see the manual "Debugging
1704 * Pending breakpoint support (also included in GDB 6.1)
1706 Support has been added to allow you to specify breakpoints in shared
1707 libraries that have not yet been loaded. If a breakpoint location
1708 cannot be found, and the "breakpoint pending" option is set to auto,
1709 GDB queries you if you wish to make the breakpoint pending on a future
1710 shared-library load. If and when GDB resolves the breakpoint symbol,
1711 the pending breakpoint is removed as one or more regular breakpoints
1714 Pending breakpoints are very useful for GCJ Java debugging.
1716 * Fixed ISO-C build problems
1718 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1719 non ISO-C code that stopped them being built using a more strict ISO-C
1720 compiler (e.g., IBM's C compiler).
1722 * Fixed build problem on IRIX 5
1724 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1725 wasn't able to compile compile on an IRIX 5 system.
1727 * Added execute permission to gdb/gdbserver/configure
1729 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1730 permission. This bug would cause configure to fail on a number of
1731 systems (Solaris, IRIX). Ref: server/519.
1733 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1735 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1736 has been updated to use constant array sizes.
1738 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1740 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1741 its generated DWARF Call Frame Info. This encoding was causing GDB to
1742 panic, that panic has been fixed. Ref: gdb/1628.
1744 * Fixed a problem when examining parameters in shared library code.
1746 When examining parameters in optimized shared library code generated
1747 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1748 not available''. GDB now correctly displays the variable's value.
1750 *** Changes in GDB 6.1:
1752 * Removed --with-mmalloc
1754 Support for the mmalloc memory manager has been removed, as it
1755 conflicted with the internal gdb byte cache.
1757 * Changes in AMD64 configurations
1759 The AMD64 target now includes the %cs and %ss registers. As a result
1760 the AMD64 remote protocol has changed; this affects the floating-point
1761 and SSE registers. If you rely on those registers for your debugging,
1762 you should upgrade gdbserver on the remote side.
1764 * Revised SPARC target
1766 The SPARC target has been completely revised, incorporating the
1767 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1768 support for LynxOS and SunOS 4 has been dropped. Calling functions
1769 from within GDB on operating systems with a non-executable stack
1770 (Solaris, OpenBSD) now works.
1774 GDB has a new C++ demangler which does a better job on the mangled
1775 names generated by current versions of g++. It also runs faster, so
1776 with this and other changes gdb should now start faster on large C++
1779 * DWARF 2 Location Expressions
1781 GDB support for location expressions has been extended to support function
1782 arguments and frame bases. Older versions of GDB could crash when they
1785 * C++ nested types and namespaces
1787 GDB's support for nested types and namespaces in C++ has been
1788 improved, especially if you use the DWARF 2 debugging format. (This
1789 is the default for recent versions of GCC on most platforms.)
1790 Specifically, if you have a class "Inner" defined within a class or
1791 namespace "Outer", then GDB realizes that the class's name is
1792 "Outer::Inner", not simply "Inner". This should greatly reduce the
1793 frequency of complaints about not finding RTTI symbols. In addition,
1794 if you are stopped at inside of a function defined within a namespace,
1795 GDB modifies its name lookup accordingly.
1797 * New native configurations
1799 NetBSD/amd64 x86_64-*-netbsd*
1800 OpenBSD/amd64 x86_64-*-openbsd*
1801 OpenBSD/alpha alpha*-*-openbsd*
1802 OpenBSD/sparc sparc-*-openbsd*
1803 OpenBSD/sparc64 sparc64-*-openbsd*
1805 * New debugging protocols
1807 M32R with SDI protocol m32r-*-elf*
1809 * "set prompt-escape-char" command deleted.
1811 The command "set prompt-escape-char" has been deleted. This command,
1812 and its very obscure effet on GDB's prompt, was never documented,
1813 tested, nor mentioned in the NEWS file.
1815 * OBSOLETE configurations and files
1817 Configurations that have been declared obsolete in this release have
1818 been commented out. Unless there is activity to revive these
1819 configurations, the next release of GDB will have their sources
1820 permanently REMOVED.
1822 Sun 3, running SunOS 3 m68*-*-sunos3*
1823 Sun 3, running SunOS 4 m68*-*-sunos4*
1824 Sun 2, running SunOS 3 m68000-*-sunos3*
1825 Sun 2, running SunOS 4 m68000-*-sunos4*
1826 Motorola 680x0 running LynxOS m68*-*-lynxos*
1827 AT&T 3b1/Unix pc m68*-att-*
1828 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1829 decstation mips-dec-* mips-little-*
1830 riscos mips-*-riscos* mips-*-sysv*
1831 sonymips mips-sony-*
1832 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1834 * REMOVED configurations and files
1836 SGI Irix-4.x mips-sgi-irix4 or iris4
1837 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1838 Z8000 simulator z8k-zilog-none or z8ksim
1839 Matsushita MN10200 w/simulator mn10200-*-*
1840 H8/500 simulator h8500-hitachi-hms or h8500hms
1841 HP/PA running BSD hppa*-*-bsd*
1842 HP/PA running OSF/1 hppa*-*-osf*
1843 HP/PA Pro target hppa*-*-pro*
1844 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1845 386BSD i[3456]86-*-bsd*
1846 Sequent family i[3456]86-sequent-sysv4*
1847 i[3456]86-sequent-sysv*
1848 i[3456]86-sequent-bsd*
1849 SPARC running LynxOS sparc-*-lynxos*
1850 SPARC running SunOS 4 sparc-*-sunos4*
1851 Tsqware Sparclet sparclet-*-*
1852 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1854 *** Changes in GDB 6.0:
1858 Support for debugging the Objective-C programming language has been
1859 integrated into GDB.
1861 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1863 DWARF 2's Call Frame Information makes available compiler generated
1864 information that more exactly describes the program's run-time stack.
1865 By using this information, GDB is able to provide more robust stack
1868 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1869 have been updated to use a new backtrace mechanism which includes
1870 DWARF 2 CFI support.
1874 GDB's remote protocol has been extended to include support for hosted
1875 file I/O (where the remote target uses GDB's file system). See GDB's
1876 remote protocol documentation for details.
1878 * All targets using the new architecture framework.
1880 All of GDB's targets have been updated to use the new internal
1881 architecture framework. The way is now open for future GDB releases
1882 to include cross-architecture native debugging support (i386 on amd64,
1885 * GNU/Linux's Thread Local Storage (TLS)
1887 GDB now includes support for for the GNU/Linux implementation of
1888 per-thread variables.
1890 * GNU/Linux's Native POSIX Thread Library (NPTL)
1892 GDB's thread code has been updated to work with either the new
1893 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1895 * Separate debug info.
1897 GDB, in conjunction with BINUTILS, now supports a mechanism for
1898 automatically loading debug information from a separate file. Instead
1899 of shipping full debug and non-debug versions of system libraries,
1900 system integrators can now instead ship just the stripped libraries
1901 and optional debug files.
1903 * DWARF 2 Location Expressions
1905 DWARF 2 Location Expressions allow the compiler to more completely
1906 describe the location of variables (even in optimized code) to the
1909 GDB now includes preliminary support for location expressions (support
1910 for DW_OP_piece is still missing).
1914 A number of long standing bugs that caused GDB to die while starting a
1915 Java application have been fixed. GDB's Java support is now
1916 considered "useable".
1918 * GNU/Linux support for fork, vfork, and exec.
1920 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1921 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1924 * GDB supports logging output to a file
1926 There are two new commands, "set logging" and "show logging", which can be
1927 used to capture GDB's output to a file.
1929 * The meaning of "detach" has changed for gdbserver
1931 The "detach" command will now resume the application, as documented. To
1932 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1935 * d10v, m68hc11 `regs' command deprecated
1937 The `info registers' command has been updated so that it displays the
1938 registers using a format identical to the old `regs' command.
1942 A new command, "maint set profile on/off", has been added. This command can
1943 be used to enable or disable profiling while running GDB, to profile a
1944 session or a set of commands. In addition there is a new configure switch,
1945 "--enable-profiling", which will cause GDB to be compiled with profiling
1946 data, for more informative profiling results.
1948 * Default MI syntax changed to "mi2".
1950 The default MI (machine interface) syntax, enabled by the command line
1951 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1952 "mi1", can be enabled by specifying the option "-i=mi1".
1954 Support for the original "mi0" syntax (included in GDB 5.0) has been
1957 Fix for gdb/192: removed extraneous space when displaying frame level.
1958 Fix for gdb/672: update changelist is now output in mi list format.
1959 Fix for gdb/702: a -var-assign that updates the value now shows up
1960 in a subsequent -var-update.
1962 * New native configurations.
1964 FreeBSD/amd64 x86_64-*-freebsd*
1966 * Multi-arched targets.
1968 HP/PA HPUX11 hppa*-*-hpux*
1969 Renesas M32R/D w/simulator m32r-*-elf*
1971 * OBSOLETE configurations and files
1973 Configurations that have been declared obsolete in this release have
1974 been commented out. Unless there is activity to revive these
1975 configurations, the next release of GDB will have their sources
1976 permanently REMOVED.
1978 Z8000 simulator z8k-zilog-none or z8ksim
1979 Matsushita MN10200 w/simulator mn10200-*-*
1980 H8/500 simulator h8500-hitachi-hms or h8500hms
1981 HP/PA running BSD hppa*-*-bsd*
1982 HP/PA running OSF/1 hppa*-*-osf*
1983 HP/PA Pro target hppa*-*-pro*
1984 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1985 Sequent family i[3456]86-sequent-sysv4*
1986 i[3456]86-sequent-sysv*
1987 i[3456]86-sequent-bsd*
1988 Tsqware Sparclet sparclet-*-*
1989 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1991 * REMOVED configurations and files
1994 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1995 IBM AIX PS/2 i[3456]86-*-aix
1996 i386 running Mach 3.0 i[3456]86-*-mach3*
1997 i386 running Mach i[3456]86-*-mach*
1998 i386 running OSF/1 i[3456]86-*osf1mk*
1999 HP/Apollo 68k Family m68*-apollo*-sysv*,
2001 m68*-hp-bsd*, m68*-hp-hpux*
2002 Argonaut Risc Chip (ARC) arc-*-*
2003 Mitsubishi D30V d30v-*-*
2004 Fujitsu FR30 fr30-*-elf*
2005 OS/9000 i[34]86-*-os9k
2006 I960 with MON960 i960-*-coff
2008 * MIPS $fp behavior changed
2010 The convenience variable $fp, for the MIPS, now consistently returns
2011 the address of the current frame's base. Previously, depending on the
2012 context, $fp could refer to either $sp or the current frame's base
2013 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2014 The GNU Source-Level Debugger''.
2016 *** Changes in GDB 5.3:
2018 * GNU/Linux shared library multi-threaded performance improved.
2020 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2021 `/proc', in preference to `ptrace' for memory reads. This may result
2022 in an improvement in the start-up time of multi-threaded, shared
2023 library applications when run under GDB. One GDB user writes: ``loads
2024 shared libs like mad''.
2026 * ``gdbserver'' now supports multi-threaded applications on some targets
2028 Support for debugging multi-threaded applications which use
2029 the GNU/Linux LinuxThreads package has been added for
2030 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2031 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2033 * GDB now supports C/C++ preprocessor macros.
2035 GDB now expands preprocessor macro invocations in C/C++ expressions,
2036 and provides various commands for showing macro definitions and how
2039 The new command `macro expand EXPRESSION' expands any macro
2040 invocations in expression, and shows the result.
2042 The new command `show macro MACRO-NAME' shows the definition of the
2043 macro named MACRO-NAME, and where it was defined.
2045 Most compilers don't include information about macros in the debugging
2046 information by default. In GCC 3.1, for example, you need to compile
2047 your program with the options `-gdwarf-2 -g3'. If the macro
2048 information is present in the executable, GDB will read it.
2050 * Multi-arched targets.
2052 DEC Alpha (partial) alpha*-*-*
2053 DEC VAX (partial) vax-*-*
2055 National Semiconductor NS32000 (partial) ns32k-*-*
2056 Motorola 68000 (partial) m68k-*-*
2057 Motorola MCORE mcore-*-*
2061 Fujitsu FRV architecture added by Red Hat frv*-*-*
2064 * New native configurations
2066 Alpha NetBSD alpha*-*-netbsd*
2067 SH NetBSD sh*-*-netbsdelf*
2068 MIPS NetBSD mips*-*-netbsd*
2069 UltraSPARC NetBSD sparc64-*-netbsd*
2071 * OBSOLETE configurations and files
2073 Configurations that have been declared obsolete in this release have
2074 been commented out. Unless there is activity to revive these
2075 configurations, the next release of GDB will have their sources
2076 permanently REMOVED.
2078 Mitsubishi D30V d30v-*-*
2079 OS/9000 i[34]86-*-os9k
2080 IBM AIX PS/2 i[3456]86-*-aix
2081 Fujitsu FR30 fr30-*-elf*
2082 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2083 Argonaut Risc Chip (ARC) arc-*-*
2084 i386 running Mach 3.0 i[3456]86-*-mach3*
2085 i386 running Mach i[3456]86-*-mach*
2086 i386 running OSF/1 i[3456]86-*osf1mk*
2087 HP/Apollo 68k Family m68*-apollo*-sysv*,
2089 m68*-hp-bsd*, m68*-hp-hpux*
2090 I960 with MON960 i960-*-coff
2092 * OBSOLETE languages
2094 CHILL, a Pascal like language used by telecommunications companies.
2096 * REMOVED configurations and files
2098 AMD 29k family via UDI a29k-amd-udi, udi29k
2099 A29K VxWorks a29k-*-vxworks
2100 AMD 29000 embedded, using EBMON a29k-none-none
2101 AMD 29000 embedded with COFF a29k-none-coff
2102 AMD 29000 embedded with a.out a29k-none-aout
2104 testsuite/gdb.hp/gdb.threads-hp/ directory
2106 * New command "set max-user-call-depth <nnn>"
2108 This command allows the user to limit the call depth of user-defined
2109 commands. The default is 1024.
2111 * Changes in FreeBSD/i386 native debugging.
2113 Support for the "generate-core-file" has been added.
2115 * New commands "dump", "append", and "restore".
2117 These commands allow data to be copied from target memory
2118 to a bfd-format or binary file (dump and append), and back
2119 from a file into memory (restore).
2121 * Improved "next/step" support on multi-processor Alpha Tru64.
2123 The previous single-step mechanism could cause unpredictable problems,
2124 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2125 of a software single-step mechanism prevents this.
2127 *** Changes in GDB 5.2.1:
2135 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2136 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2137 Fix, by Joel Brobecker imported from mainline.
2139 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2140 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2141 Fix, by Fred Fish, imported from mainline.
2143 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2144 Surprisingly enough, it works now.
2145 By Michal Ludvig, imported from mainline.
2147 i386 hardware watchpoint support:
2148 avoid misses on second run for some targets.
2149 By Pierre Muller, imported from mainline.
2151 *** Changes in GDB 5.2:
2153 * New command "set trust-readonly-sections on[off]".
2155 This command is a hint that tells gdb that read-only sections
2156 really are read-only (ie. that their contents will not change).
2157 In this mode, gdb will go to the object file rather than the
2158 target to read memory from read-only sections (such as ".text").
2159 This can be a significant performance improvement on some
2160 (notably embedded) targets.
2162 * New command "generate-core-file" (or "gcore").
2164 This new gdb command allows the user to drop a core file of the child
2165 process state at any time. So far it's been implemented only for
2166 GNU/Linux and Solaris, but should be relatively easily ported to other
2167 hosts. Argument is core file name (defaults to core.<pid>).
2169 * New command line option
2171 GDB now accepts --pid or -p followed by a process id.
2173 * Change in command line behavior -- corefiles vs. process ids.
2175 There is a subtle behavior in the way in which GDB handles
2176 command line arguments. The first non-flag argument is always
2177 a program to debug, but the second non-flag argument may either
2178 be a corefile or a process id. Previously, GDB would attempt to
2179 open the second argument as a corefile, and if that failed, would
2180 issue a superfluous error message and then attempt to attach it as
2181 a process. Now, if the second argument begins with a non-digit,
2182 it will be treated as a corefile. If it begins with a digit,
2183 GDB will attempt to attach it as a process, and if no such process
2184 is found, will then attempt to open it as a corefile.
2186 * Changes in ARM configurations.
2188 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2189 configuration is fully multi-arch.
2191 * New native configurations
2193 ARM NetBSD arm*-*-netbsd*
2194 x86 OpenBSD i[3456]86-*-openbsd*
2195 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2196 Sparc64 running FreeBSD sparc64-*-freebsd*
2200 Sanyo XStormy16 xstormy16-elf
2202 * OBSOLETE configurations and files
2204 Configurations that have been declared obsolete in this release have
2205 been commented out. Unless there is activity to revive these
2206 configurations, the next release of GDB will have their sources
2207 permanently REMOVED.
2209 AMD 29k family via UDI a29k-amd-udi, udi29k
2210 A29K VxWorks a29k-*-vxworks
2211 AMD 29000 embedded, using EBMON a29k-none-none
2212 AMD 29000 embedded with COFF a29k-none-coff
2213 AMD 29000 embedded with a.out a29k-none-aout
2215 testsuite/gdb.hp/gdb.threads-hp/ directory
2217 * REMOVED configurations and files
2219 TI TMS320C80 tic80-*-*
2221 PowerPC Solaris powerpcle-*-solaris*
2222 PowerPC Windows NT powerpcle-*-cygwin32
2223 PowerPC Netware powerpc-*-netware*
2224 Harris/CXUX m88k m88*-harris-cxux*
2225 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2226 ns32k-utek-sysv* ns32k-utek-*
2227 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2228 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2229 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2230 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2231 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2233 * Changes to command line processing
2235 The new `--args' feature can be used to specify command-line arguments
2236 for the inferior from gdb's command line.
2238 * Changes to key bindings
2240 There is a new `operate-and-get-next' function bound to `C-o'.
2242 *** Changes in GDB 5.1.1
2244 Fix compile problem on DJGPP.
2246 Fix a problem with floating-point registers on the i386 being
2249 Fix to stop GDB crashing on .debug_str debug info.
2251 Numerous documentation fixes.
2253 Numerous testsuite fixes.
2255 *** Changes in GDB 5.1:
2257 * New native configurations
2259 Alpha FreeBSD alpha*-*-freebsd*
2260 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2261 MIPS GNU/Linux mips*-*-linux*
2262 MIPS SGI Irix 6.x mips*-sgi-irix6*
2263 ia64 AIX ia64-*-aix*
2264 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2268 Motorola 68HC11 and 68HC12 m68hc11-elf
2270 UltraSparc running GNU/Linux sparc64-*-linux*
2272 * OBSOLETE configurations and files
2274 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2275 Harris/CXUX m88k m88*-harris-cxux*
2276 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2277 ns32k-utek-sysv* ns32k-utek-*
2278 TI TMS320C80 tic80-*-*
2280 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2281 PowerPC Solaris powerpcle-*-solaris*
2282 PowerPC Windows NT powerpcle-*-cygwin32
2283 PowerPC Netware powerpc-*-netware*
2284 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2285 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2286 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2287 Apple Macintosh (MPW) host N/A
2289 stuff.c (Program to stuff files into a specially prepared space in kdb)
2290 kdb-start.c (Main loop for the standalone kernel debugger)
2292 Configurations that have been declared obsolete in this release have
2293 been commented out. Unless there is activity to revive these
2294 configurations, the next release of GDB will have their sources
2295 permanently REMOVED.
2297 * REMOVED configurations and files
2299 Altos 3068 m68*-altos-*
2300 Convex c1-*-*, c2-*-*
2302 ARM RISCix arm-*-* (as host)
2306 * GDB has been converted to ISO C.
2308 GDB's source code has been converted to ISO C. In particular, the
2309 sources are fully protoized, and rely on standard headers being
2314 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2316 * The MI enabled by default.
2318 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2319 revised and enabled by default. Packages which use GDB as a debugging
2320 engine behind a UI or another front end are encouraged to switch to
2321 using the GDB/MI interface, instead of the old annotations interface
2322 which is now deprecated.
2324 * Support for debugging Pascal programs.
2326 GDB now includes support for debugging Pascal programs. The following
2327 main features are supported:
2329 - Pascal-specific data types such as sets;
2331 - automatic recognition of Pascal sources based on file-name
2334 - Pascal-style display of data types, variables, and functions;
2336 - a Pascal expression parser.
2338 However, some important features are not yet supported.
2340 - Pascal string operations are not supported at all;
2342 - there are some problems with boolean types;
2344 - Pascal type hexadecimal constants are not supported
2345 because they conflict with the internal variables format;
2347 - support for Pascal objects and classes is not full yet;
2349 - unlike Pascal, GDB is case-sensitive for symbol names.
2351 * Changes in completion.
2353 Commands such as `shell', `run' and `set args', which pass arguments
2354 to inferior programs, now complete on file names, similar to what
2355 users expect at the shell prompt.
2357 Commands which accept locations, such as `disassemble', `print',
2358 `breakpoint', `until', etc. now complete on filenames as well as
2359 program symbols. Thus, if you type "break foob TAB", and the source
2360 files linked into the programs include `foobar.c', that file name will
2361 be one of the candidates for completion. However, file names are not
2362 considered for completion after you typed a colon that delimits a file
2363 name from a name of a function in that file, as in "break foo.c:bar".
2365 `set demangle-style' completes on available demangling styles.
2367 * New platform-independent commands:
2369 It is now possible to define a post-hook for a command as well as a
2370 hook that runs before the command. For more details, see the
2371 documentation of `hookpost' in the GDB manual.
2373 * Changes in GNU/Linux native debugging.
2375 Support for debugging multi-threaded programs has been completely
2376 revised for all platforms except m68k and sparc. You can now debug as
2377 many threads as your system allows you to have.
2379 Attach/detach is supported for multi-threaded programs.
2381 Support for SSE registers was added for x86. This doesn't work for
2382 multi-threaded programs though.
2384 * Changes in MIPS configurations.
2386 Multi-arch support is enabled for all MIPS configurations.
2388 GDB can now be built as native debugger on SGI Irix 6.x systems for
2389 debugging n32 executables. (Debugging 64-bit executables is not yet
2392 * Unified support for hardware watchpoints in all x86 configurations.
2394 Most (if not all) native x86 configurations support hardware-assisted
2395 breakpoints and watchpoints in a unified manner. This support
2396 implements debug register sharing between watchpoints, which allows to
2397 put a virtually infinite number of watchpoints on the same address,
2398 and also supports watching regions up to 16 bytes with several debug
2401 The new maintenance command `maintenance show-debug-regs' toggles
2402 debugging print-outs in functions that insert, remove, and test
2403 watchpoints and hardware breakpoints.
2405 * Changes in the DJGPP native configuration.
2407 New command ``info dos sysinfo'' displays assorted information about
2408 the CPU, OS, memory, and DPMI server.
2410 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2411 display information about segment descriptors stored in GDT, LDT, and
2414 New commands ``info dos pde'' and ``info dos pte'' display entries
2415 from Page Directory and Page Tables (for now works with CWSDPMI only).
2416 New command ``info dos address-pte'' displays the Page Table entry for
2417 a given linear address.
2419 GDB can now pass command lines longer than 126 characters to the
2420 program being debugged (requires an update to the libdbg.a library
2421 which is part of the DJGPP development kit).
2423 DWARF2 debug info is now supported.
2425 It is now possible to `step' and `next' through calls to `longjmp'.
2427 * Changes in documentation.
2429 All GDB documentation was converted to GFDL, the GNU Free
2430 Documentation License.
2432 Tracepoints-related commands are now fully documented in the GDB
2435 TUI, the Text-mode User Interface, is now documented in the manual.
2437 Tracepoints-related commands are now fully documented in the GDB
2440 The "GDB Internals" manual now has an index. It also includes
2441 documentation of `ui_out' functions, GDB coding standards, x86
2442 hardware watchpoints, and memory region attributes.
2444 * GDB's version number moved to ``version.in''
2446 The Makefile variable VERSION has been replaced by the file
2447 ``version.in''. People creating GDB distributions should update the
2448 contents of this file.
2452 GUD support is now a standard part of the EMACS distribution.
2454 *** Changes in GDB 5.0:
2456 * Improved support for debugging FP programs on x86 targets
2458 Unified and much-improved support for debugging floating-point
2459 programs on all x86 targets. In particular, ``info float'' now
2460 displays the FP registers in the same format on all x86 targets, with
2461 greater level of detail.
2463 * Improvements and bugfixes in hardware-assisted watchpoints
2465 It is now possible to watch array elements, struct members, and
2466 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2467 on x86 targets no longer erroneously trigger when the address is
2470 * Improvements in the native DJGPP version of GDB
2472 The distribution now includes all the scripts and auxiliary files
2473 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2474 machines ``out of the box''.
2476 The DJGPP version can now debug programs that use signals. It is
2477 possible to catch signals that happened in the debuggee, deliver
2478 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2479 would kill the program being debugged.) Programs that hook hardware
2480 interrupts (keyboard, timer, etc.) can also be debugged.
2482 It is now possible to debug DJGPP programs that redirect their
2483 standard handles or switch them to raw (as opposed to cooked) mode, or
2484 even close them. The command ``run < foo > bar'' works as expected,
2485 and ``info terminal'' reports useful information about the debuggee's
2486 terminal, including raw/cooked mode, redirection, etc.
2488 The DJGPP version now uses termios functions for console I/O, which
2489 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2492 DOS-style file names with drive letters are now fully supported by
2495 It is now possible to debug DJGPP programs that switch their working
2496 directory. It is also possible to rerun the debuggee any number of
2497 times without restarting GDB; thus, you can use the same setup,
2498 breakpoints, etc. for many debugging sessions.
2500 * New native configurations
2502 ARM GNU/Linux arm*-*-linux*
2503 PowerPC GNU/Linux powerpc-*-linux*
2507 Motorola MCore mcore-*-*
2508 x86 VxWorks i[3456]86-*-vxworks*
2509 PowerPC VxWorks powerpc-*-vxworks*
2510 TI TMS320C80 tic80-*-*
2512 * OBSOLETE configurations
2514 Altos 3068 m68*-altos-*
2515 Convex c1-*-*, c2-*-*
2517 ARM RISCix arm-*-* (as host)
2520 Configurations that have been declared obsolete will be commented out,
2521 but the code will be left in place. If there is no activity to revive
2522 these configurations before the next release of GDB, the sources will
2523 be permanently REMOVED.
2525 * Gould support removed
2527 Support for the Gould PowerNode and NP1 has been removed.
2529 * New features for SVR4
2531 On SVR4 native platforms (such as Solaris), if you attach to a process
2532 without first loading a symbol file, GDB will now attempt to locate and
2533 load symbols from the running process's executable file.
2535 * Many C++ enhancements
2537 C++ support has been greatly improved. Overload resolution now works properly
2538 in almost all cases. RTTI support is on the way.
2540 * Remote targets can connect to a sub-program
2542 A popen(3) style serial-device has been added. This device starts a
2543 sub-process (such as a stand-alone simulator) and then communicates
2544 with that. The sub-program to run is specified using the syntax
2545 ``|<program> <args>'' vis:
2547 (gdb) set remotedebug 1
2548 (gdb) target extended-remote |mn10300-elf-sim program-args
2550 * MIPS 64 remote protocol
2552 A long standing bug in the mips64 remote protocol where by GDB
2553 expected certain 32 bit registers (ex SR) to be transfered as 32
2554 instead of 64 bits has been fixed.
2556 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2557 added to provide backward compatibility with older versions of GDB.
2559 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2561 The command ``set remotebinarydownload'' command has been replaced by
2562 ``set remote X-packet''. Other commands in ``set remote'' family
2563 include ``set remote P-packet''.
2565 * Breakpoint commands accept ranges.
2567 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2568 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2569 ``tracepoint passcount'' also accepts a range of tracepoints.
2571 * ``apropos'' command added.
2573 The ``apropos'' command searches through command names and
2574 documentation strings, printing out matches, making it much easier to
2575 try to find a command that does what you are looking for.
2579 A new machine oriented interface (MI) has been added to GDB. This
2580 interface is designed for debug environments running GDB as a separate
2581 process. This is part of the long term libGDB project. See the
2582 "GDB/MI" chapter of the GDB manual for further information. It can be
2583 enabled by configuring with:
2585 .../configure --enable-gdbmi
2587 *** Changes in GDB-4.18:
2589 * New native configurations
2591 HP-UX 10.20 hppa*-*-hpux10.20
2592 HP-UX 11.x hppa*-*-hpux11.0*
2593 M68K GNU/Linux m68*-*-linux*
2597 Fujitsu FR30 fr30-*-elf*
2598 Intel StrongARM strongarm-*-*
2599 Mitsubishi D30V d30v-*-*
2601 * OBSOLETE configurations
2603 Gould PowerNode, NP1 np1-*-*, pn-*-*
2605 Configurations that have been declared obsolete will be commented out,
2606 but the code will be left in place. If there is no activity to revive
2607 these configurations before the next release of GDB, the sources will
2608 be permanently REMOVED.
2612 As a compatibility experiment, GDB's source files buildsym.h and
2613 buildsym.c have been converted to pure standard C, no longer
2614 containing any K&R compatibility code. We believe that all systems in
2615 use today either come with a standard C compiler, or have a GCC port
2616 available. If this is not true, please report the affected
2617 configuration to bug-gdb@gnu.org immediately. See the README file for
2618 information about getting a standard C compiler if you don't have one
2623 GDB now uses readline 2.2.
2625 * set extension-language
2627 You can now control the mapping between filename extensions and source
2628 languages by using the `set extension-language' command. For instance,
2629 you can ask GDB to treat .c files as C++ by saying
2630 set extension-language .c c++
2631 The command `info extensions' lists all of the recognized extensions
2632 and their associated languages.
2634 * Setting processor type for PowerPC and RS/6000
2636 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2637 you can use the `set processor' command to specify what variant of the
2638 PowerPC family you are debugging. The command
2642 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2643 following PowerPC and RS6000 variants:
2645 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2646 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2648 403GC IBM PowerPC 403GC
2649 505 Motorola PowerPC 505
2650 860 Motorola PowerPC 860 or 850
2651 601 Motorola PowerPC 601
2652 602 Motorola PowerPC 602
2653 603 Motorola/IBM PowerPC 603 or 603e
2654 604 Motorola PowerPC 604 or 604e
2655 750 Motorola/IBM PowerPC 750 or 750
2657 At the moment, this command just tells GDB what to name the
2658 special-purpose processor registers. Since almost all the affected
2659 registers are inaccessible to user-level programs, this command is
2660 only useful for remote debugging in its present form.
2664 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2665 more extensive support for HP-UX. Added features include shared
2666 library support, kernel threads and hardware watchpoints for 11.00,
2667 support for HP's ANSI C and C++ compilers, and a compatibility mode
2668 for xdb and dbx commands.
2672 HP's donation includes the new concept of catchpoints, which is a
2673 generalization of the old catch command. On HP-UX, it is now possible
2674 to catch exec, fork, and vfork, as well as library loading.
2676 This means that the existing catch command has changed; its first
2677 argument now specifies the type of catch to be set up. See the
2678 output of "help catch" for a list of catchpoint types.
2680 * Debugging across forks
2682 On HP-UX, you can choose which process to debug when a fork() happens
2687 HP has donated a curses-based terminal user interface (TUI). To get
2688 it, build with --enable-tui. Although this can be enabled for any
2689 configuration, at present it only works for native HP debugging.
2691 * GDB remote protocol additions
2693 A new protocol packet 'X' that writes binary data is now available.
2694 Default behavior is to try 'X', then drop back to 'M' if the stub
2695 fails to respond. The settable variable `remotebinarydownload'
2696 allows explicit control over the use of 'X'.
2698 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2699 full 64-bit address. The command
2701 set remoteaddresssize 32
2703 can be used to revert to the old behaviour. For existing remote stubs
2704 the change should not be noticed, as the additional address information
2707 In order to assist in debugging stubs, you may use the maintenance
2708 command `packet' to send any text string to the stub. For instance,
2710 maint packet heythere
2712 sends the packet "$heythere#<checksum>". Note that it is very easy to
2713 disrupt a debugging session by sending the wrong packet at the wrong
2716 The compare-sections command allows you to compare section data on the
2717 target to what is in the executable file without uploading or
2718 downloading, by comparing CRC checksums.
2720 * Tracing can collect general expressions
2722 You may now collect general expressions at tracepoints. This requires
2723 further additions to the target-side stub; see tracepoint.c and
2724 doc/agentexpr.texi for further details.
2726 * mask-address variable for Mips
2728 For Mips targets, you may control the zeroing of the upper 32 bits of
2729 a 64-bit address by entering `set mask-address on'. This is mainly
2730 of interest to users of embedded R4xxx and R5xxx processors.
2732 * Higher serial baud rates
2734 GDB's serial code now allows you to specify baud rates 57600, 115200,
2735 230400, and 460800 baud. (Note that your host system may not be able
2736 to achieve all of these rates.)
2740 The i960 configuration now includes an initial implementation of a
2741 builtin simulator, contributed by Jim Wilson.
2744 *** Changes in GDB-4.17:
2746 * New native configurations
2748 Alpha GNU/Linux alpha*-*-linux*
2749 Unixware 2.x i[3456]86-unixware2*
2750 Irix 6.x mips*-sgi-irix6*
2751 PowerPC GNU/Linux powerpc-*-linux*
2752 PowerPC Solaris powerpcle-*-solaris*
2753 Sparc GNU/Linux sparc-*-linux*
2754 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2758 Argonaut Risc Chip (ARC) arc-*-*
2759 Hitachi H8/300S h8300*-*-*
2760 Matsushita MN10200 w/simulator mn10200-*-*
2761 Matsushita MN10300 w/simulator mn10300-*-*
2762 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2763 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2764 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2765 Mitsubishi D10V w/simulator d10v-*-*
2766 Mitsubishi M32R/D w/simulator m32r-*-elf*
2767 Tsqware Sparclet sparclet-*-*
2768 NEC V850 w/simulator v850-*-*
2770 * New debugging protocols
2772 ARM with RDI protocol arm*-*-*
2773 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2774 DDB and LSI variants of PMON protocol mips*-*-*
2775 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2776 PowerPC with SDS protocol powerpc{,le}-*-eabi
2777 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2781 All configurations can now understand and use the DWARF 2 debugging
2782 format. The choice is automatic, if the symbol file contains DWARF 2
2787 GDB now includes basic Java language support. This support is
2788 only useful with Java compilers that produce native machine code.
2790 * solib-absolute-prefix and solib-search-path
2792 For SunOS and SVR4 shared libraries, you may now set the prefix for
2793 loading absolute shared library symbol files, and the search path for
2794 locating non-absolute shared library symbol files.
2796 * Live range splitting
2798 GDB can now effectively debug code for which GCC has performed live
2799 range splitting as part of its optimization. See gdb/doc/LRS for
2800 more details on the expected format of the stabs information.
2804 GDB's support for the GNU Hurd, including thread debugging, has been
2805 updated to work with current versions of the Hurd.
2809 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2810 instruction set. ARM GDB automatically detects when Thumb
2811 instructions are in use, and adjusts disassembly and backtracing
2816 GDB's MIPS target configurations now handle the MIP16 16-bit
2821 GDB now includes support for overlays; if an executable has been
2822 linked such that multiple sections are based at the same address, GDB
2823 will decide which section to use for symbolic info. You can choose to
2824 control the decision manually, using overlay commands, or implement
2825 additional target-side support and use "overlay load-target" to bring
2826 in the overlay mapping. Do "help overlay" for more detail.
2830 The command "info symbol <address>" displays information about
2831 the symbol at the specified address.
2835 The standard remote protocol now includes an extension that allows
2836 asynchronous collection and display of trace data. This requires
2837 extensive support in the target-side debugging stub. Tracing mode
2838 includes a new interaction mode in GDB and new commands: see the
2839 file tracepoint.c for more details.
2843 Configurations for embedded MIPS now include a simulator contributed
2844 by Cygnus Solutions. The simulator supports the instruction sets
2845 of most MIPS variants.
2849 Sparc configurations may now include the ERC32 simulator contributed
2850 by the European Space Agency. The simulator is not built into
2851 Sparc targets by default; configure with --enable-sim to include it.
2855 For target configurations that may include multiple variants of a
2856 basic architecture (such as MIPS and SH), you may now set the
2857 architecture explicitly. "set arch" sets, "info arch" lists
2858 the possible architectures.
2860 *** Changes in GDB-4.16:
2862 * New native configurations
2864 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2865 M68K NetBSD m68k-*-netbsd*
2866 PowerPC AIX 4.x powerpc-*-aix*
2867 PowerPC MacOS powerpc-*-macos*
2868 PowerPC Windows NT powerpcle-*-cygwin32
2869 RS/6000 AIX 4.x rs6000-*-aix4*
2873 ARM with RDP protocol arm-*-*
2874 I960 with MON960 i960-*-coff
2875 MIPS VxWorks mips*-*-vxworks*
2876 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2877 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2879 Matra Sparclet sparclet-*-*
2883 The powerpc-eabi configuration now includes the PSIM simulator,
2884 contributed by Andrew Cagney, with assistance from Mike Meissner.
2885 PSIM is a very elaborate model of the PowerPC, including not only
2886 basic instruction set execution, but also details of execution unit
2887 performance and I/O hardware. See sim/ppc/README for more details.
2891 GDB now works with Solaris 2.5.
2893 * Windows 95/NT native
2895 GDB will now work as a native debugger on Windows 95 and Windows NT.
2896 To build it from source, you must use the "gnu-win32" environment,
2897 which uses a DLL to emulate enough of Unix to run the GNU tools.
2898 Further information, binaries, and sources are available at
2899 ftp.cygnus.com, under pub/gnu-win32.
2901 * dont-repeat command
2903 If a user-defined command includes the command `dont-repeat', then the
2904 command will not be repeated if the user just types return. This is
2905 useful if the command is time-consuming to run, so that accidental
2906 extra keystrokes don't run the same command many times.
2908 * Send break instead of ^C
2910 The standard remote protocol now includes an option to send a break
2911 rather than a ^C to the target in order to interrupt it. By default,
2912 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2914 * Remote protocol timeout
2916 The standard remote protocol includes a new variable `remotetimeout'
2917 that allows you to set the number of seconds before GDB gives up trying
2918 to read from the target. The default value is 2.
2920 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2922 By default GDB will automatically keep track of objects as they are
2923 loaded and unloaded by the dynamic linker. By using the command `set
2924 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2925 when shared library events occur, thus allowing you to set breakpoints
2926 in shared libraries which are explicitly loaded by the inferior.
2928 Note this feature does not work on hpux8. On hpux9 you must link
2929 /usr/lib/end.o into your program. This feature should work
2930 automatically on hpux10.
2932 * Irix 5.x hardware watchpoint support
2934 Irix 5 configurations now support the use of hardware watchpoints.
2936 * Mips protocol "SYN garbage limit"
2938 When debugging a Mips target using the `target mips' protocol, you
2939 may set the number of characters that GDB will ignore by setting
2940 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2941 every character. The default value is 1050.
2943 * Recording and replaying remote debug sessions
2945 If you set `remotelogfile' to the name of a file, gdb will write to it
2946 a recording of a remote debug session. This recording may then be
2947 replayed back to gdb using "gdbreplay". See gdbserver/README for
2948 details. This is useful when you have a problem with GDB while doing
2949 remote debugging; you can make a recording of the session and send it
2950 to someone else, who can then recreate the problem.
2952 * Speedups for remote debugging
2954 GDB includes speedups for downloading and stepping MIPS systems using
2955 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2956 and more efficient S-record downloading.
2958 * Memory use reductions and statistics collection
2960 GDB now uses less memory and reports statistics about memory usage.
2961 Try the `maint print statistics' command, for example.
2963 *** Changes in GDB-4.15:
2965 * Psymtabs for XCOFF
2967 The symbol reader for AIX GDB now uses partial symbol tables. This
2968 can greatly improve startup time, especially for large executables.
2970 * Remote targets use caching
2972 Remote targets now use a data cache to speed up communication with the
2973 remote side. The data cache could lead to incorrect results because
2974 it doesn't know about volatile variables, thus making it impossible to
2975 debug targets which use memory mapped I/O devices. `set remotecache
2976 off' turns the the data cache off.
2978 * Remote targets may have threads
2980 The standard remote protocol now includes support for multiple threads
2981 in the target system, using new protocol commands 'H' and 'T'. See
2982 gdb/remote.c for details.
2986 If GDB is configured with `--enable-netrom', then it will include
2987 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2988 acts as though it is a bank of ROM on the target board, but you can
2989 write into it over the network. GDB's support consists only of
2990 support for fast loading into the emulated ROM; to debug, you must use
2991 another protocol, such as standard remote protocol. The usual
2992 sequence is something like
2994 target nrom <netrom-hostname>
2996 target remote <netrom-hostname>:1235
3000 GDB now includes support for the Apple Macintosh, as a host only. It
3001 may be run as either an MPW tool or as a standalone application, and
3002 it can debug through the serial port. All the usual GDB commands are
3003 available, but to the target command, you must supply "serial" as the
3004 device type instead of "/dev/ttyXX". See mpw-README in the main
3005 directory for more information on how to build. The MPW configuration
3006 scripts */mpw-config.in support only a few targets, and only the
3007 mips-idt-ecoff target has been tested.
3011 GDB configuration now uses autoconf. This is not user-visible,
3012 but does simplify configuration and building.
3016 GDB now supports hpux10.
3018 *** Changes in GDB-4.14:
3020 * New native configurations
3022 x86 FreeBSD i[345]86-*-freebsd
3023 x86 NetBSD i[345]86-*-netbsd
3024 NS32k NetBSD ns32k-*-netbsd
3025 Sparc NetBSD sparc-*-netbsd
3029 A29K VxWorks a29k-*-vxworks
3030 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3031 CPU32 EST-300 emulator m68*-*-est*
3032 PowerPC ELF powerpc-*-elf
3035 * Alpha OSF/1 support for procfs
3037 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3038 possible to attach to running processes. As the mounting of the /proc
3039 filesystem is optional on the Alpha, GDB automatically determines
3040 the availability of /proc during startup. This can lead to problems
3041 if /proc is unmounted after GDB has been started.
3043 * Arguments to user-defined commands
3045 User commands may accept up to 10 arguments separated by whitespace.
3046 Arguments are accessed within the user command via $arg0..$arg9. A
3049 print $arg0 + $arg1 + $arg2
3051 To execute the command use:
3054 Defines the command "adder" which prints the sum of its three arguments.
3055 Note the arguments are text substitutions, so they may reference variables,
3056 use complex expressions, or even perform inferior function calls.
3058 * New `if' and `while' commands
3060 This makes it possible to write more sophisticated user-defined
3061 commands. Both commands take a single argument, which is the
3062 expression to evaluate, and must be followed by the commands to
3063 execute, one per line, if the expression is nonzero, the list being
3064 terminated by the word `end'. The `if' command list may include an
3065 `else' word, which causes the following commands to be executed only
3066 if the expression is zero.
3068 * Fortran source language mode
3070 GDB now includes partial support for Fortran 77. It will recognize
3071 Fortran programs and can evaluate a subset of Fortran expressions, but
3072 variables and functions may not be handled correctly. GDB will work
3073 with G77, but does not yet know much about symbols emitted by other
3076 * Better HPUX support
3078 Most debugging facilities now work on dynamic executables for HPPAs
3079 running hpux9 or later. You can attach to running dynamically linked
3080 processes, but by default the dynamic libraries will be read-only, so
3081 for instance you won't be able to put breakpoints in them. To change
3082 that behavior do the following before running the program:
3088 This will cause the libraries to be mapped private and read-write.
3089 To revert to the normal behavior, do this:
3095 You cannot set breakpoints or examine data in the library until after
3096 the library is loaded if the function/data symbols do not have
3099 GDB can now also read debug symbols produced by the HP C compiler on
3100 HPPAs (sorry, no C++, Fortran or 68k support).
3102 * Target byte order now dynamically selectable
3104 You can choose which byte order to use with a target system, via the
3105 commands "set endian big" and "set endian little", and you can see the
3106 current setting by using "show endian". You can also give the command
3107 "set endian auto", in which case GDB will use the byte order
3108 associated with the executable. Currently, only embedded MIPS
3109 configurations support dynamic selection of target byte order.
3111 * New DOS host serial code
3113 This version uses DPMI interrupts to handle buffered I/O, so you
3114 no longer need to run asynctsr when debugging boards connected to
3117 *** Changes in GDB-4.13:
3119 * New "complete" command
3121 This lists all the possible completions for the rest of the line, if it
3122 were to be given as a command itself. This is intended for use by emacs.
3124 * Trailing space optional in prompt
3126 "set prompt" no longer adds a space for you after the prompt you set. This
3127 allows you to set a prompt which ends in a space or one that does not.
3129 * Breakpoint hit counts
3131 "info break" now displays a count of the number of times the breakpoint
3132 has been hit. This is especially useful in conjunction with "ignore"; you
3133 can ignore a large number of breakpoint hits, look at the breakpoint info
3134 to see how many times the breakpoint was hit, then run again, ignoring one
3135 less than that number, and this will get you quickly to the last hit of
3138 * Ability to stop printing at NULL character
3140 "set print null-stop" will cause GDB to stop printing the characters of
3141 an array when the first NULL is encountered. This is useful when large
3142 arrays actually contain only short strings.
3144 * Shared library breakpoints
3146 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3147 breakpoints in shared libraries before the executable is run.
3149 * Hardware watchpoints
3151 There is a new hardware breakpoint for the watch command for sparclite
3152 targets. See gdb/sparclite/hw_breakpoint.note.
3154 Hardware watchpoints are also now supported under GNU/Linux.
3158 Annotations have been added. These are for use with graphical interfaces,
3159 and are still experimental. Currently only gdba.el uses these.
3161 * Improved Irix 5 support
3163 GDB now works properly with Irix 5.2.
3165 * Improved HPPA support
3167 GDB now works properly with the latest GCC and GAS.
3169 * New native configurations
3171 Sequent PTX4 i[34]86-sequent-ptx4
3172 HPPA running OSF/1 hppa*-*-osf*
3173 Atari TT running SVR4 m68*-*-sysv4*
3174 RS/6000 LynxOS rs6000-*-lynxos*
3178 OS/9000 i[34]86-*-os9k
3179 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3182 * Hitachi SH7000 and E7000-PC ICE support
3184 There is now support for communicating with the Hitachi E7000-PC ICE.
3185 This is available automatically when GDB is configured for the SH.
3189 As usual, a variety of small fixes and improvements, both generic
3190 and configuration-specific. See the ChangeLog for more detail.
3192 *** Changes in GDB-4.12:
3194 * Irix 5 is now supported
3198 GDB-4.12 on the HPPA has a number of changes which make it unable
3199 to debug the output from the currently released versions of GCC and
3200 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3201 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3202 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3205 *** Changes in GDB-4.11:
3207 * User visible changes:
3211 The "set remotedebug" option is now consistent between the mips remote
3212 target, remote targets using the gdb-specific protocol, UDI (AMD's
3213 debug protocol for the 29k) and the 88k bug monitor. It is now an
3214 integer specifying a debug level (normally 0 or 1, but 2 means more
3215 debugging info for the mips target).
3217 * DEC Alpha native support
3219 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3220 debug info, but GDB works fairly well with the DEC compiler and should
3221 work with a future GCC release. See the README file for a few
3222 Alpha-specific notes.
3224 * Preliminary thread implementation
3226 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3228 * LynxOS native and target support for 386
3230 This release has been hosted on LynxOS 2.2, and also can be configured
3231 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3234 * Improvements in C++ mangling/demangling.
3236 This release has much better g++ debugging, specifically in name
3237 mangling/demangling, virtual function calls, print virtual table,
3238 call methods, ...etc.
3240 *** Changes in GDB-4.10:
3242 * User visible changes:
3244 Remote debugging using the GDB-specific (`target remote') protocol now
3245 supports the `load' command. This is only useful if you have some
3246 other way of getting the stub to the target system, and you can put it
3247 somewhere in memory where it won't get clobbered by the download.
3249 Filename completion now works.
3251 When run under emacs mode, the "info line" command now causes the
3252 arrow to point to the line specified. Also, "info line" prints
3253 addresses in symbolic form (as well as hex).
3255 All vxworks based targets now support a user settable option, called
3256 vxworks-timeout. This option represents the number of seconds gdb
3257 should wait for responses to rpc's. You might want to use this if
3258 your vxworks target is, perhaps, a slow software simulator or happens
3259 to be on the far side of a thin network line.
3263 This release contains support for using a DEC alpha as a GDB host for
3264 cross debugging. Native alpha debugging is not supported yet.
3267 *** Changes in GDB-4.9:
3271 This is the first GDB release which is accompanied by a matching testsuite.
3272 The testsuite requires installation of dejagnu, which should be available
3273 via ftp from most sites that carry GNU software.
3277 'Cfront' style demangling has had its name changed to 'ARM' style, to
3278 emphasize that it was written from the specifications in the C++ Annotated
3279 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3280 disclaimers, it still generated too much confusion with users attempting to
3281 use gdb with AT&T cfront.
3285 GDB now uses a standard remote interface to a simulator library.
3286 So far, the library contains simulators for the Zilog Z8001/2, the
3287 Hitachi H8/300, H8/500 and Super-H.
3289 * New targets supported
3291 H8/300 simulator h8300-hitachi-hms or h8300hms
3292 H8/500 simulator h8500-hitachi-hms or h8500hms
3293 SH simulator sh-hitachi-hms or sh
3294 Z8000 simulator z8k-zilog-none or z8ksim
3295 IDT MIPS board over serial line mips-idt-ecoff
3297 Cross-debugging to GO32 targets is supported. It requires a custom
3298 version of the i386-stub.c module which is integrated with the
3299 GO32 memory extender.
3301 * New remote protocols
3303 MIPS remote debugging protocol.
3305 * New source languages supported
3307 This version includes preliminary support for Chill, a Pascal like language
3308 used by telecommunications companies. Chill support is also being integrated
3309 into the GNU compiler, but we don't know when it will be publically available.
3312 *** Changes in GDB-4.8:
3314 * HP Precision Architecture supported
3316 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3317 version of this support was available as a set of patches from the
3318 University of Utah. GDB does not support debugging of programs
3319 compiled with the HP compiler, because HP will not document their file
3320 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3321 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3323 Many problems in the preliminary version have been fixed.
3325 * Faster and better demangling
3327 We have improved template demangling and fixed numerous bugs in the GNU style
3328 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3329 character types (wchar_t) are now supported. Demangling of each symbol is now
3330 only done once, and is cached when the symbol table for a file is read in.
3331 This results in a small increase in memory usage for C programs, a moderate
3332 increase in memory usage for C++ programs, and a fantastic speedup in
3335 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3336 from the specifications in the Annotated Reference Manual, which AT&T's
3337 compiler does not actually implement.
3339 * G++ multiple inheritance compiler problem
3341 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3342 inheritance lattices was reworked to properly discover ambiguities. We
3343 recently found an example which causes this new algorithm to fail in a
3344 very subtle way, producing bad debug information for those classes.
3345 The file 'gcc.patch' (in this directory) can be applied to gcc to
3346 circumvent the problem. A future GCC release will contain a complete
3349 The previous G++ debug info problem (mentioned below for the gdb-4.7
3350 release) is fixed in gcc version 2.3.2.
3352 * Improved configure script
3354 The `configure' script will now attempt to guess your system type if
3355 you don't supply a host system type. The old scheme of supplying a
3356 host system triplet is preferable over using this. All the magic is
3357 done in the new `config.guess' script. Examine it for details.
3359 We have also brought our configure script much more in line with the FSF's
3360 version. It now supports the --with-xxx options. In particular,
3361 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3362 The resulting GDB will not be able to read arbitrary object file formats --
3363 only the format ``expected'' to be used on the configured target system.
3364 We hope to make this the default in a future release.
3366 * Documentation improvements
3368 There's new internal documentation on how to modify GDB, and how to
3369 produce clean changes to the code. We implore people to read it
3370 before submitting changes.
3372 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3373 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3374 `info' files are also provided. To build `info' files from scratch,
3375 you will need the latest `makeinfo' release, which will be available in
3376 a future texinfo-X.Y release.
3378 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3379 We're not sure exactly which versions have this problem, but it has
3380 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3381 or better. If that isn't possible, there is a patch in
3382 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3383 around this problem.
3387 GDB now supports array constants that can be used in expressions typed in by
3388 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3389 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3392 The new directory `gdb/sparclite' contains a program that demonstrates
3393 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3395 * New native hosts supported
3397 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3398 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3400 * New targets supported
3402 AMD 29k family via UDI a29k-amd-udi or udi29k
3404 * New file formats supported
3406 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3407 HPUX core files, and SCO 3.2v2 core files.
3411 Attaching to processes now works again; thanks for the many bug reports.
3413 We have also stomped on a bunch of core dumps caused by
3414 printf_filtered("%s") problems.
3416 We eliminated a copyright problem on the rpc and ptrace header files
3417 for VxWorks, which was discovered at the last minute during the 4.7
3418 release. You should now be able to build a VxWorks GDB.
3420 You can now interrupt gdb while an attached process is running. This
3421 will cause the attached process to stop, and give control back to GDB.
3423 We fixed problems caused by using too many file descriptors
3424 for reading symbols from object files and libraries. This was
3425 especially a problem for programs that used many (~100) shared
3428 The `step' command now only enters a subroutine if there is line number
3429 information for the subroutine. Otherwise it acts like the `next'
3430 command. Previously, `step' would enter subroutines if there was
3431 any debugging information about the routine. This avoids problems
3432 when using `cc -g1' on MIPS machines.
3434 * Internal improvements
3436 GDB's internal interfaces have been improved to make it easier to support
3437 debugging of multiple languages in the future.
3439 GDB now uses a common structure for symbol information internally.
3440 Minimal symbols (derived from linkage symbols in object files), partial
3441 symbols (from a quick scan of debug information), and full symbols
3442 contain a common subset of information, making it easier to write
3443 shared code that handles any of them.
3445 * New command line options
3447 We now accept --silent as an alias for --quiet.
3451 The memory-mapped-malloc library is now licensed under the GNU Library
3452 General Public License.
3454 *** Changes in GDB-4.7:
3456 * Host/native/target split
3458 GDB has had some major internal surgery to untangle the support for
3459 hosts and remote targets. Now, when you configure GDB for a remote
3460 target, it will no longer load in all of the support for debugging
3461 local programs on the host. When fully completed and tested, this will
3462 ensure that arbitrary host/target combinations are possible.
3464 The primary conceptual shift is to separate the non-portable code in
3465 GDB into three categories. Host specific code is required any time GDB
3466 is compiled on that host, regardless of the target. Target specific
3467 code relates to the peculiarities of the target, but can be compiled on
3468 any host. Native specific code is everything else: it can only be
3469 built when the host and target are the same system. Child process
3470 handling and core file support are two common `native' examples.
3472 GDB's use of /proc for controlling Unix child processes is now cleaner.
3473 It has been split out into a single module under the `target_ops' vector,
3474 plus two native-dependent functions for each system that uses /proc.
3476 * New hosts supported
3478 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3479 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3480 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3482 * New targets supported
3484 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3485 68030 and CPU32 m68030-*-*, m68332-*-*
3487 * New native hosts supported
3489 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3490 (386bsd is not well tested yet)
3491 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3493 * New file formats supported
3495 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3496 supports reading of `a.out.adobe' object files, which are an a.out
3497 format extended with minimal information about multiple sections.
3501 `show copying' is the same as the old `info copying'.
3502 `show warranty' is the same as `info warrantee'.
3503 These were renamed for consistency. The old commands continue to work.
3505 `info handle' is a new alias for `info signals'.
3507 You can now define pre-command hooks, which attach arbitrary command
3508 scripts to any command. The commands in the hook will be executed
3509 prior to the user's command. You can also create a hook which will be
3510 executed whenever the program stops. See gdb.texinfo.
3514 We now deal with Cfront style name mangling, and can even extract type
3515 info from mangled symbols. GDB can automatically figure out which
3516 symbol mangling style your C++ compiler uses.
3518 Calling of methods and virtual functions has been improved as well.
3522 The crash that occured when debugging Sun Ansi-C compiled binaries is
3523 fixed. This was due to mishandling of the extra N_SO stabs output
3526 We also finally got Ultrix 4.2 running in house, and fixed core file
3527 support, with help from a dozen people on the net.
3529 John M. Farrell discovered that the reason that single-stepping was so
3530 slow on all of the Mips based platforms (primarily SGI and DEC) was
3531 that we were trying to demangle and lookup a symbol used for internal
3532 purposes on every instruction that was being stepped through. Changing
3533 the name of that symbol so that it couldn't be mistaken for a C++
3534 mangled symbol sped things up a great deal.
3536 Rich Pixley sped up symbol lookups in general by getting much smarter
3537 about when C++ symbol mangling is necessary. This should make symbol
3538 completion (TAB on the command line) much faster. It's not as fast as
3539 we'd like, but it's significantly faster than gdb-4.6.
3543 A new user controllable variable 'call_scratch_address' can
3544 specify the location of a scratch area to be used when GDB
3545 calls a function in the target. This is necessary because the
3546 usual method of putting the scratch area on the stack does not work
3547 in systems that have separate instruction and data spaces.
3549 We integrated changes to support the 29k UDI (Universal Debugger
3550 Interface), but discovered at the last minute that we didn't have all
3551 of the appropriate copyright paperwork. We are working with AMD to
3552 resolve this, and hope to have it available soon.
3556 We have sped up the remote serial line protocol, especially for targets
3557 with lots of registers. It now supports a new `expedited status' ('T')
3558 message which can be used in place of the existing 'S' status message.
3559 This allows the remote stub to send only the registers that GDB
3560 needs to make a quick decision about single-stepping or conditional
3561 breakpoints, eliminating the need to fetch the entire register set for
3562 each instruction being stepped through.
3564 The GDB remote serial protocol now implements a write-through cache for
3565 registers, only re-reading the registers if the target has run.
3567 There is also a new remote serial stub for SPARC processors. You can
3568 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3569 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3570 processor with a serial port.
3574 Configure.in files have become much easier to read and modify. A new
3575 `table driven' format makes it more obvious what configurations are
3576 supported, and what files each one uses.
3580 There is a new opcodes library which will eventually contain all of the
3581 disassembly routines and opcode tables. At present, it only contains
3582 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3583 disassembler (binutils/objdump) to share these routines.
3585 The libiberty library is now copylefted under the GNU Library General
3586 Public License. This allows more liberal use, and was done so libg++
3587 can use it. This makes no difference to GDB, since the Library License
3588 grants all the rights from the General Public License.
3592 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3593 reference to the stabs symbol info used by the debugger. It is (as far
3594 as we know) the only published document on this fascinating topic. We
3595 encourage you to read it, compare it to the stabs information on your
3596 system, and send improvements on the document in general (to
3597 bug-gdb@prep.ai.mit.edu).
3599 And, of course, many bugs have been fixed.
3602 *** Changes in GDB-4.6:
3604 * Better support for C++ function names
3606 GDB now accepts as input the "demangled form" of C++ overloaded function
3607 names and member function names, and can do command completion on such names
3608 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3609 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3610 Make use of command completion, it is your friend.
3612 GDB also now accepts a variety of C++ mangled symbol formats. They are
3613 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3614 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3615 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3616 for the list of formats.
3618 * G++ symbol mangling problem
3620 Recent versions of gcc have a bug in how they emit debugging information for
3621 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3622 directory) can be applied to gcc to fix the problem. Alternatively, if you
3623 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3624 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3625 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3628 * New 'maintenance' command
3630 All of the commands related to hacking GDB internals have been moved out of
3631 the main command set, and now live behind the 'maintenance' command. This
3632 can also be abbreviated as 'mt'. The following changes were made:
3634 dump-me -> maintenance dump-me
3635 info all-breakpoints -> maintenance info breakpoints
3636 printmsyms -> maintenance print msyms
3637 printobjfiles -> maintenance print objfiles
3638 printpsyms -> maintenance print psymbols
3639 printsyms -> maintenance print symbols
3641 The following commands are new:
3643 maintenance demangle Call internal GDB demangler routine to
3644 demangle a C++ link name and prints the result.
3645 maintenance print type Print a type chain for a given symbol
3647 * Change to .gdbinit file processing
3649 We now read the $HOME/.gdbinit file before processing the argv arguments
3650 (e.g. reading symbol files or core files). This allows global parameters to
3651 be set, which will apply during the symbol reading. The ./.gdbinit is still
3652 read after argv processing.
3654 * New hosts supported
3656 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3658 GNU/Linux support i386-unknown-linux or linux
3660 We are also including code to support the HP/PA running BSD and HPUX. This
3661 is almost guaranteed not to work, as we didn't have time to test or build it
3662 for this release. We are including it so that the more adventurous (or
3663 masochistic) of you can play with it. We also had major problems with the
3664 fact that the compiler that we got from HP doesn't support the -g option.
3667 * New targets supported
3669 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3671 * More smarts about finding #include files
3673 GDB now remembers the compilation directory for all include files, and for
3674 all files from which C is generated (like yacc and lex sources). This
3675 greatly improves GDB's ability to find yacc/lex sources, and include files,
3676 especially if you are debugging your program from a directory different from
3677 the one that contains your sources.
3679 We also fixed a bug which caused difficulty with listing and setting
3680 breakpoints in include files which contain C code. (In the past, you had to
3681 try twice in order to list an include file that you hadn't looked at before.)
3683 * Interesting infernals change
3685 GDB now deals with arbitrary numbers of sections, where the symbols for each
3686 section must be relocated relative to that section's landing place in the
3687 target's address space. This work was needed to support ELF with embedded
3688 stabs used by Solaris-2.0.
3690 * Bug fixes (of course!)
3692 There have been loads of fixes for the following things:
3693 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3694 i960, stabs, DOS(GO32), procfs, etc...
3696 See the ChangeLog for details.
3698 *** Changes in GDB-4.5:
3700 * New machines supported (host and target)
3702 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3704 SGI Irix-4.x mips-sgi-irix4 or iris4
3706 * New malloc package
3708 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3709 Mmalloc is capable of handling mutiple heaps of memory. It is also
3710 capable of saving a heap to a file, and then mapping it back in later.
3711 This can be used to greatly speedup the startup of GDB by using a
3712 pre-parsed symbol table which lives in a mmalloc managed heap. For
3713 more details, please read mmalloc/mmalloc.texi.
3717 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3718 'help info proc' for details.
3720 * MIPS ecoff symbol table format
3722 The code that reads MIPS symbol table format is now supported on all hosts.
3723 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3726 * File name changes for MS-DOS
3728 Many files in the config directories have been renamed to make it easier to
3729 support GDB on MS-DOSe systems (which have very restrictive file name
3730 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3731 environment) is close to working but has some remaining problems. Note
3732 that debugging of DOS programs is not supported, due to limitations
3733 in the ``operating system'', but it can be used to host cross-debugging.
3735 * Cross byte order fixes
3737 Many fixes have been made to support cross debugging of Sparc and MIPS
3738 targets from hosts whose byte order differs.
3740 * New -mapped and -readnow options
3742 If memory-mapped files are available on your system through the 'mmap'
3743 system call, you can use the -mapped option on the `file' or
3744 `symbol-file' commands to cause GDB to write the symbols from your
3745 program into a reusable file. If the program you are debugging is
3746 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3747 Future GDB debugging sessions will notice the presence of this file,
3748 and will quickly map in symbol information from it, rather than reading
3749 the symbol table from the executable program. Using the '-mapped'
3750 option in a GDB `file' or `symbol-file' command has the same effect as
3751 starting GDB with the '-mapped' command-line option.
3753 You can cause GDB to read the entire symbol table immediately by using
3754 the '-readnow' option with any of the commands that load symbol table
3755 information (or on the GDB command line). This makes the command
3756 slower, but makes future operations faster.
3758 The -mapped and -readnow options are typically combined in order to
3759 build a `fred.syms' file that contains complete symbol information.
3760 A simple GDB invocation to do nothing but build a `.syms' file for future
3763 gdb -batch -nx -mapped -readnow programname
3765 The `.syms' file is specific to the host machine on which GDB is run.
3766 It holds an exact image of GDB's internal symbol table. It cannot be
3767 shared across multiple host platforms.
3769 * longjmp() handling
3771 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3772 siglongjmp() without losing control. This feature has not yet been ported to
3773 all systems. It currently works on many 386 platforms, all MIPS-based
3774 platforms (SGI, DECstation, etc), and Sun3/4.
3778 Preliminary work has been put in to support the new Solaris OS from Sun. At
3779 this time, it can control and debug processes, but it is not capable of
3784 As always, many many bug fixes. The major areas were with g++, and mipsread.
3785 People using the MIPS-based platforms should experience fewer mysterious
3786 crashes and trashed symbol tables.
3788 *** Changes in GDB-4.4:
3790 * New machines supported (host and target)
3792 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3794 BSD Reno on Vax vax-dec-bsd
3795 Ultrix on Vax vax-dec-ultrix
3797 * New machines supported (target)
3799 AMD 29000 embedded, using EBMON a29k-none-none
3803 GDB continues to improve its handling of C++. `References' work better.
3804 The demangler has also been improved, and now deals with symbols mangled as
3805 per the Annotated C++ Reference Guide.
3807 GDB also now handles `stabs' symbol information embedded in MIPS
3808 `ecoff' symbol tables. Since the ecoff format was not easily
3809 extensible to handle new languages such as C++, this appeared to be a
3810 good way to put C++ debugging info into MIPS binaries. This option
3811 will be supported in the GNU C compiler, version 2, when it is
3814 * New features for SVR4
3816 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3817 shared libraries. Debugging dynamically linked programs should present
3818 only minor differences from debugging statically linked programs.
3820 The `info proc' command will print out information about any process
3821 on an SVR4 system (including the one you are debugging). At the moment,
3822 it prints the address mappings of the process.
3824 If you bring up GDB on another SVR4 system, please send mail to
3825 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3827 * Better dynamic linking support in SunOS
3829 Reading symbols from shared libraries which contain debugging symbols
3830 now works properly. However, there remain issues such as automatic
3831 skipping of `transfer vector' code during function calls, which
3832 make it harder to debug code in a shared library, than to debug the
3833 same code linked statically.
3837 GDB is now using the latest `getopt' routines from the FSF. This
3838 version accepts the -- prefix for options with long names. GDB will
3839 continue to accept the old forms (-option and +option) as well.
3840 Various single letter abbreviations for options have been explicity
3841 added to the option table so that they won't get overshadowed in the
3842 future by other options that begin with the same letter.
3846 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3847 Many assorted bugs have been handled. Many more remain to be handled.
3848 See the various ChangeLog files (primarily in gdb and bfd) for details.
3851 *** Changes in GDB-4.3:
3853 * New machines supported (host and target)
3855 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3856 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3857 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3859 * Almost SCO Unix support
3861 We had hoped to support:
3862 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3863 (except for core file support), but we discovered very late in the release
3864 that it has problems with process groups that render gdb unusable. Sorry
3865 about that. I encourage people to fix it and post the fixes.
3867 * Preliminary ELF and DWARF support
3869 GDB can read ELF object files on System V Release 4, and can handle
3870 debugging records for C, in DWARF format, in ELF files. This support
3871 is preliminary. If you bring up GDB on another SVR4 system, please
3872 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3877 GDB now uses the latest `readline' library. One user-visible change
3878 is that two tabs will list possible command completions, which previously
3879 required typing M-? (meta-question mark, or ESC ?).
3883 The `stepi' bug that many of you noticed has been squashed.
3884 Many bugs in C++ have been handled. Many more remain to be handled.
3885 See the various ChangeLog files (primarily in gdb and bfd) for details.
3887 * State of the MIPS world (in case you wondered):
3889 GDB can understand the symbol tables emitted by the compilers
3890 supplied by most vendors of MIPS-based machines, including DEC. These
3891 symbol tables are in a format that essentially nobody else uses.
3893 Some versions of gcc come with an assembler post-processor called
3894 mips-tfile. This program is required if you want to do source-level
3895 debugging of gcc-compiled programs. I believe FSF does not ship
3896 mips-tfile with gcc version 1, but it will eventually come with gcc
3899 Debugging of g++ output remains a problem. g++ version 1.xx does not
3900 really support it at all. (If you're lucky, you should be able to get
3901 line numbers and stack traces to work, but no parameters or local
3902 variables.) With some work it should be possible to improve the
3905 When gcc version 2 is released, you will have somewhat better luck.
3906 However, even then you will get confusing results for inheritance and
3909 We will eventually provide full debugging of g++ output on
3910 DECstations. This will probably involve some kind of stabs-in-ecoff
3911 encapulation, but the details have not been worked out yet.
3914 *** Changes in GDB-4.2:
3916 * Improved configuration
3918 Only one copy of `configure' exists now, and it is not self-modifying.
3919 Porting BFD is simpler.
3923 The `step' and `next' commands now only stop at the first instruction
3924 of a source line. This prevents the multiple stops that used to occur
3925 in switch statements, for-loops, etc. `Step' continues to stop if a
3926 function that has debugging information is called within the line.
3930 Lots of small bugs fixed. More remain.
3932 * New host supported (not target)
3934 Intel 386 PC clone running Mach i386-none-mach
3937 *** Changes in GDB-4.1:
3939 * Multiple source language support
3941 GDB now has internal scaffolding to handle several source languages.
3942 It determines the type of each source file from its filename extension,
3943 and will switch expression parsing and number formatting to match the
3944 language of the function in the currently selected stack frame.
3945 You can also specifically set the language to be used, with
3946 `set language c' or `set language modula-2'.
3950 GDB now has preliminary support for the GNU Modula-2 compiler,
3951 currently under development at the State University of New York at
3952 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3953 continue through the fall of 1991 and into 1992.
3955 Other Modula-2 compilers are currently not supported, and attempting to
3956 debug programs compiled with them will likely result in an error as the
3957 symbol table is read. Feel free to work on it, though!
3959 There are hooks in GDB for strict type checking and range checking,
3960 in the `Modula-2 philosophy', but they do not currently work.
3964 GDB can now write to executable and core files (e.g. patch
3965 a variable's value). You must turn this switch on, specify
3966 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3967 by assigning a new value to a variable. Modifications take
3970 * Automatic SunOS shared library reading
3972 When you run your program, GDB automatically determines where its
3973 shared libraries (if any) have been loaded, and reads their symbols.
3974 The `share' command is no longer needed. This also works when
3975 examining core files.
3979 You can specify the number of lines that the `list' command shows.
3982 * New machines supported (host and target)
3984 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3985 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3986 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3988 * New hosts supported (not targets)
3990 IBM RT/PC: romp-ibm-aix or rtpc
3992 * New targets supported (not hosts)
3994 AMD 29000 embedded with COFF a29k-none-coff
3995 AMD 29000 embedded with a.out a29k-none-aout
3996 Ultracomputer remote kernel debug a29k-nyu-kern
3998 * New remote interfaces
4004 *** Changes in GDB-4.0:
4008 Wide output is wrapped at good places to make the output more readable.
4010 Gdb now supports cross-debugging from a host machine of one type to a
4011 target machine of another type. Communication with the target system
4012 is over serial lines. The ``target'' command handles connecting to the
4013 remote system; the ``load'' command will download a program into the
4014 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4015 also supports debugging of realtime processes running under VxWorks,
4016 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4017 stub on the target system.
4019 New CPUs supported include the AMD 29000 and Intel 960.
4021 GDB now reads object files and symbol tables via a ``binary file''
4022 library, which allows a single copy of GDB to debug programs of multiple
4023 object file types such as a.out and coff.
4025 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4026 refcard.dvi and refcard.ps are available to format it).
4029 * Control-Variable user interface simplified
4031 All variables that control the operation of the debugger can be set
4032 by the ``set'' command, and displayed by the ``show'' command.
4034 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4035 ``Show prompt'' produces the response:
4036 Gdb's prompt is new-gdb=>.
4038 What follows are the NEW set commands. The command ``help set'' will
4039 print a complete list of old and new set commands. ``help set FOO''
4040 will give a longer description of the variable FOO. ``show'' will show
4041 all of the variable descriptions and their current settings.
4043 confirm on/off: Enables warning questions for operations that are
4044 hard to recover from, e.g. rerunning the program while
4045 it is already running. Default is ON.
4047 editing on/off: Enables EMACS style command line editing
4048 of input. Previous lines can be recalled with
4049 control-P, the current line can be edited with control-B,
4050 you can search for commands with control-R, etc.
4053 history filename NAME: NAME is where the gdb command history
4054 will be stored. The default is .gdb_history,
4055 or the value of the environment variable
4058 history size N: The size, in commands, of the command history. The
4059 default is 256, or the value of the environment variable
4062 history save on/off: If this value is set to ON, the history file will
4063 be saved after exiting gdb. If set to OFF, the
4064 file will not be saved. The default is OFF.
4066 history expansion on/off: If this value is set to ON, then csh-like
4067 history expansion will be performed on
4068 command line input. The default is OFF.
4070 radix N: Sets the default radix for input and output. It can be set
4071 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4072 in the current radix, so "set radix 10" is always a no-op.
4074 height N: This integer value is the number of lines on a page. Default
4075 is 24, the current `stty rows'' setting, or the ``li#''
4076 setting from the termcap entry matching the environment
4079 width N: This integer value is the number of characters on a line.
4080 Default is 80, the current `stty cols'' setting, or the ``co#''
4081 setting from the termcap entry matching the environment
4084 Note: ``set screensize'' is obsolete. Use ``set height'' and
4085 ``set width'' instead.
4087 print address on/off: Print memory addresses in various command displays,
4088 such as stack traces and structure values. Gdb looks
4089 more ``symbolic'' if you turn this off; it looks more
4090 ``machine level'' with it on. Default is ON.
4092 print array on/off: Prettyprint arrays. New convenient format! Default
4095 print demangle on/off: Print C++ symbols in "source" form if on,
4098 print asm-demangle on/off: Same, for assembler level printouts
4101 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4104 * Support for Epoch Environment.
4106 The epoch environment is a version of Emacs v18 with windowing. One
4107 new command, ``inspect'', is identical to ``print'', except that if you
4108 are running in the epoch environment, the value is printed in its own
4112 * Support for Shared Libraries
4114 GDB can now debug programs and core files that use SunOS shared libraries.
4115 Symbols from a shared library cannot be referenced
4116 before the shared library has been linked with the program (this
4117 happens after you type ``run'' and before the function main() is entered).
4118 At any time after this linking (including when examining core files
4119 from dynamically linked programs), gdb reads the symbols from each
4120 shared library when you type the ``sharedlibrary'' command.
4121 It can be abbreviated ``share''.
4123 sharedlibrary REGEXP: Load shared object library symbols for files
4124 matching a unix regular expression. No argument
4125 indicates to load symbols for all shared libraries.
4127 info sharedlibrary: Status of loaded shared libraries.
4132 A watchpoint stops execution of a program whenever the value of an
4133 expression changes. Checking for this slows down execution
4134 tremendously whenever you are in the scope of the expression, but is
4135 quite useful for catching tough ``bit-spreader'' or pointer misuse
4136 problems. Some machines such as the 386 have hardware for doing this
4137 more quickly, and future versions of gdb will use this hardware.
4139 watch EXP: Set a watchpoint (breakpoint) for an expression.
4141 info watchpoints: Information about your watchpoints.
4143 delete N: Deletes watchpoint number N (same as breakpoints).
4144 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4145 enable N: Re-enables watchpoint number N (same as breakpoints).
4148 * C++ multiple inheritance
4150 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4153 * C++ exception handling
4155 Gdb now supports limited C++ exception handling. Besides the existing
4156 ability to breakpoint on an exception handler, gdb can breakpoint on
4157 the raising of an exception (before the stack is peeled back to the
4160 catch FOO: If there is a FOO exception handler in the dynamic scope,
4161 set a breakpoint to catch exceptions which may be raised there.
4162 Multiple exceptions (``catch foo bar baz'') may be caught.
4164 info catch: Lists all exceptions which may be caught in the
4165 current stack frame.
4168 * Minor command changes
4170 The command ``call func (arg, arg, ...)'' now acts like the print
4171 command, except it does not print or save a value if the function's result
4172 is void. This is similar to dbx usage.
4174 The ``up'' and ``down'' commands now always print the frame they end up
4175 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4176 frames without printing.
4178 * New directory command
4180 'dir' now adds directories to the FRONT of the source search path.
4181 The path starts off empty. Source files that contain debug information
4182 about the directory in which they were compiled can be found even
4183 with an empty path; Sun CC and GCC include this information. If GDB can't
4184 find your source file in the current directory, type "dir .".
4186 * Configuring GDB for compilation
4188 For normal use, type ``./configure host''. See README or gdb.texinfo
4191 GDB now handles cross debugging. If you are remotely debugging between
4192 two different machines, type ``./configure host -target=targ''.
4193 Host is the machine where GDB will run; targ is the machine
4194 where the program that you are debugging will run.