1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.2
6 * The "catch syscall" command now works on mips*-linux* targets.
8 * The -data-disassemble MI command now supports modes 2 and 3 for
9 dumping the instruction opcodes.
11 * New command line options
13 -data-directory DIR Specify DIR as the "data-directory".
14 This is mostly for testing purposes.
16 * The "maint set python auto-load on|off" command has been renamed to
17 "set auto-load-scripts on|off".
19 * GDB has a new command: "set directories".
20 It is like the "dir" command except that it replaces the
21 source path list instead of augmenting it.
23 * GDB now understands thread names.
25 On GNU/Linux, "info threads" will display the thread name as set by
26 prctl or pthread_setname_np.
28 There is also a new command, "thread name", which can be used to
29 assign a name internally for GDB to display.
32 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
33 has been integrated into GDB.
37 ** GDB values in Python are now callable if the value represents a
38 function. For example, if 'some_value' represents a function that
39 takes two integer parameters and returns a value, you can call
40 that function like so:
42 result = some_value (10,20)
44 ** Module gdb.types has been added.
45 It contains a collection of utilities for working with gdb.Types objects:
46 get_basic_type, has_field, make_enum_dict.
48 ** Module gdb.printing has been added.
49 It contains utilities for writing and registering pretty-printers.
50 New classes: PrettyPrinter, SubPrettyPrinter,
51 RegexpCollectionPrettyPrinter.
52 New function: register_pretty_printer.
54 ** New commands "info pretty-printers", "enable pretty-printer" and
55 "disable pretty-printer" have been added.
57 ** gdb.parameter("directories") is now available.
59 ** New function gdb.newest_frame returns the newest frame in the
62 ** The gdb.InferiorThread class has a new "name" attribute. This
63 holds the thread's name.
67 ** GDB now puts template parameters in scope when debugging in an
68 instantiation. For example, if you have:
70 template<int X> int func (void) { return X; }
72 then if you step into func<5>, "print X" will show "5". This
73 feature requires proper debuginfo support from the compiler; it
76 ** The motion commands "next", "finish", "until", and "advance" now
77 work better when exceptions are thrown. In particular, GDB will
78 no longer lose control of the inferior; instead, the GDB will
79 stop the inferior at the point at which the exception is caught.
80 This functionality requires a change in the exception handling
81 code that was introduced in GCC 4.5.
83 * GDB now follows GCC's rules on accessing volatile objects when
84 reading or writing target state during expression evaluation.
85 One notable difference to prior behavior is that "print x = 0"
86 no longer generates a read of x; the value of the assignment is
87 now always taken directly from the value being assigned.
89 * GDB now has some support for using labels in the program's source in
90 linespecs. For instance, you can use "advance label" to continue
93 * GDB now has support for reading and writing a new .gdb_index
94 section. This section holds a fast index of DWARF debugging
95 information and can be used to greatly speed up GDB startup and
96 operation. See the documentation for `save gdb-index' for details.
98 * The "watch" command now accepts an optional "-location" argument.
99 When used, this causes GDB to watch the memory referred to by the
100 expression. Such a watchpoint is never deleted due to it going out
103 * GDB now supports thread debugging of core dumps on GNU/Linux.
105 GDB now activates thread debugging using the libthread_db library
106 when debugging GNU/Linux core dumps, similarly to when debugging
107 live processes. As a result, when debugging a core dump file, GDB
108 is now able to display pthread_t ids of threads. For example, "info
109 threads" shows the same output as when debugging the process when it
110 was live. In earlier releases, you'd see something like this:
113 * 1 LWP 6780 main () at main.c:10
115 While now you see this:
118 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
120 It is also now possible to inspect TLS variables when debugging core
123 When debugging a core dump generated on a machine other than the one
124 used to run GDB, you may need to point GDB at the correct
125 libthread_db library with the "set libthread-db-search-path"
126 command. See the user manual for more details on this command.
128 * New features in the GDB remote stub, GDBserver
130 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
131 and i686 LynxOS (version 5.x).
133 ** GDBserver is now supported on Blackfin Linux.
135 * New native configurations
137 ia64 HP-UX ia64-*-hpux*
141 Analog Devices, Inc. Blackfin Processor bfin-*
143 * Ada task switching is now supported on sparc-elf targets when
144 debugging a program using the Ravenscar Profile. For more information,
145 see the "Tasking Support when using the Ravenscar Profile" section
146 in the GDB user manual.
148 * Guile support was removed.
150 * New features in the GNU simulator
152 ** The --map-info flag lists all known core mappings.
154 *** Changes in GDB 7.2
156 * Shared library support for remote targets by default
158 When GDB is configured for a generic, non-OS specific target, like
159 for example, --target=arm-eabi or one of the many *-*-elf targets,
160 GDB now queries remote stubs for loaded shared libraries using the
161 `qXfer:libraries:read' packet. Previously, shared library support
162 was always disabled for such configurations.
166 ** Argument Dependent Lookup (ADL)
168 In C++ ADL lookup directs function search to the namespaces of its
169 arguments even if the namespace has not been imported.
179 Here the compiler will search for `foo' in the namespace of 'b'
180 and find A::foo. GDB now supports this. This construct is commonly
181 used in the Standard Template Library for operators.
183 ** Improved User Defined Operator Support
185 In addition to member operators, GDB now supports lookup of operators
186 defined in a namespace and imported with a `using' directive, operators
187 defined in the global scope, operators imported implicitly from an
188 anonymous namespace, and the ADL operators mentioned in the previous
190 GDB now also supports proper overload resolution for all the previously
191 mentioned flavors of operators.
193 ** static const class members
195 Printing of static const class members that are initialized in the
196 class definition has been fixed.
198 * Windows Thread Information Block access.
200 On Windows targets, GDB now supports displaying the Windows Thread
201 Information Block (TIB) structure. This structure is visible either
202 by using the new command `info w32 thread-information-block' or, by
203 dereferencing the new convenience variable named `$_tlb', a
204 thread-specific pointer to the TIB. This feature is also supported
205 when remote debugging using GDBserver.
209 Static tracepoints are calls in the user program into a tracing
210 library. One such library is a port of the LTTng kernel tracer to
211 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
212 When debugging with GDBserver, GDB now supports combining the GDB
213 tracepoint machinery with such libraries. For example: the user can
214 use GDB to probe a static tracepoint marker (a call from the user
215 program into the tracing library) with the new "strace" command (see
216 "New commands" below). This creates a "static tracepoint" in the
217 breakpoint list, that can be manipulated with the same feature set
218 as fast and regular tracepoints. E.g., collect registers, local and
219 global variables, collect trace state variables, and define
220 tracepoint conditions. In addition, the user can collect extra
221 static tracepoint marker specific data, by collecting the new
222 $_sdata internal variable. When analyzing the trace buffer, you can
223 inspect $_sdata like any other variable available to GDB. For more
224 information, see the "Tracepoints" chapter in GDB user manual. New
225 remote packets have been defined to support static tracepoints, see
226 the "New remote packets" section below.
228 * Better reconstruction of tracepoints after disconnected tracing
230 GDB will attempt to download the original source form of tracepoint
231 definitions when starting a trace run, and then will upload these
232 upon reconnection to the target, resulting in a more accurate
233 reconstruction of the tracepoints that are in use on the target.
237 You can now exercise direct control over the ways that GDB can
238 affect your program. For instance, you can disallow the setting of
239 breakpoints, so that the program can run continuously (assuming
240 non-stop mode). In addition, the "observer" variable is available
241 to switch all of the different controls; in observer mode, GDB
242 cannot affect the target's behavior at all, which is useful for
243 tasks like diagnosing live systems in the field.
245 * The new convenience variable $_thread holds the number of the
252 Return the address of the Windows Thread Information Block of a given thread.
256 In response to several of the tracepoint packets, the target may now
257 also respond with a number of intermediate `qRelocInsn' request
258 packets before the final result packet, to have GDB handle
259 relocating an instruction to execute at a different address. This
260 is particularly useful for stubs that support fast tracepoints. GDB
261 reports support for this feature in the qSupported packet.
265 List static tracepoint markers in the target program.
269 List static tracepoint markers at a given address in the target
272 qXfer:statictrace:read
274 Read the static trace data collected (by a `collect $_sdata'
275 tracepoint action). The remote stub reports support for this packet
276 to gdb's qSupported query.
280 Send the current settings of GDB's permission flags.
284 Send part of the source (textual) form of a tracepoint definition,
285 which includes location, conditional, and action list.
287 * The source command now accepts a -s option to force searching for the
288 script in the source search path even if the script name specifies
291 * New features in the GDB remote stub, GDBserver
293 - GDBserver now support tracepoints (including fast tracepoints, and
294 static tracepoints). The feature is currently supported by the
295 i386-linux and amd64-linux builds. See the "Tracepoints support
296 in gdbserver" section in the manual for more information.
298 GDBserver JIT compiles the tracepoint's conditional agent
299 expression bytecode into native code whenever possible for low
300 overhead dynamic tracepoints conditionals. For such tracepoints,
301 an expression that examines program state is evaluated when the
302 tracepoint is reached, in order to determine whether to capture
303 trace data. If the condition is simple and false, processing the
304 tracepoint finishes very quickly and no data is gathered.
306 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
307 for static tracepoints support.
309 - GDBserver now supports x86_64 Windows 64-bit debugging.
311 * GDB now sends xmlRegisters= in qSupported packet to indicate that
312 it understands register description.
314 * The --batch flag now disables pagination and queries.
316 * X86 general purpose registers
318 GDB now supports reading/writing byte, word and double-word x86
319 general purpose registers directly. This means you can use, say,
320 $ah or $ax to refer, respectively, to the byte register AH and
321 16-bit word register AX that are actually portions of the 32-bit
322 register EAX or 64-bit register RAX.
324 * The `commands' command now accepts a range of breakpoints to modify.
325 A plain `commands' following a command that creates multiple
326 breakpoints affects all the breakpoints set by that command. This
327 applies to breakpoints set by `rbreak', and also applies when a
328 single `break' command creates multiple breakpoints (e.g.,
329 breakpoints on overloaded c++ functions).
331 * The `rbreak' command now accepts a filename specification as part of
332 its argument, limiting the functions selected by the regex to those
333 in the specified file.
335 * Support for remote debugging Windows and SymbianOS shared libraries
336 from Unix hosts has been improved. Non Windows GDB builds now can
337 understand target reported file names that follow MS-DOS based file
338 system semantics, such as file names that include drive letters and
339 use the backslash character as directory separator. This makes it
340 possible to transparently use the "set sysroot" and "set
341 solib-search-path" on Unix hosts to point as host copies of the
342 target's shared libraries. See the new command "set
343 target-file-system-kind" described below, and the "Commands to
344 specify files" section in the user manual for more information.
348 eval template, expressions...
349 Convert the values of one or more expressions under the control
350 of the string template to a command line, and call it.
352 set target-file-system-kind unix|dos-based|auto
353 show target-file-system-kind
354 Set or show the assumed file system kind for target reported file
357 save breakpoints <filename>
358 Save all current breakpoint definitions to a file suitable for use
359 in a later debugging session. To read the saved breakpoint
360 definitions, use the `source' command.
362 `save tracepoints' is a new alias for `save-tracepoints'. The latter
365 info static-tracepoint-markers
366 Display information about static tracepoint markers in the target.
368 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
369 Define a static tracepoint by probing a marker at the given
370 function, line, address, or marker ID.
374 Enable and disable observer mode.
376 set may-write-registers on|off
377 set may-write-memory on|off
378 set may-insert-breakpoints on|off
379 set may-insert-tracepoints on|off
380 set may-insert-fast-tracepoints on|off
381 set may-interrupt on|off
382 Set individual permissions for GDB effects on the target. Note that
383 some of these settings can have undesirable or surprising
384 consequences, particularly when changed in the middle of a session.
385 For instance, disabling the writing of memory can prevent
386 breakpoints from being inserted, cause single-stepping to fail, or
387 even crash your program, if you disable after breakpoints have been
388 inserted. However, GDB should not crash.
390 set record memory-query on|off
391 show record memory-query
392 Control whether to stop the inferior if memory changes caused
393 by an instruction cannot be recorded.
398 The disassemble command now supports "start,+length" form of two arguments.
402 ** GDB now provides a new directory location, called the python directory,
403 where Python scripts written for GDB can be installed. The location
404 of that directory is <data-directory>/python, where <data-directory>
405 is the GDB data directory. For more details, see section `Scripting
406 GDB using Python' in the manual.
408 ** The GDB Python API now has access to breakpoints, symbols, symbol
409 tables, program spaces, inferiors, threads and frame's code blocks.
410 Additionally, GDB Parameters can now be created from the API, and
411 manipulated via set/show in the CLI.
413 ** New functions gdb.target_charset, gdb.target_wide_charset,
414 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
416 ** New exception gdb.GdbError.
418 ** Pretty-printers are now also looked up in the current program space.
420 ** Pretty-printers can now be individually enabled and disabled.
422 ** GDB now looks for names of Python scripts to auto-load in a
423 special section named `.debug_gdb_scripts', in addition to looking
424 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
426 * Tracepoint actions were unified with breakpoint commands. In particular,
427 there are no longer differences in "info break" output for breakpoints and
428 tracepoints and the "commands" command can be used for both tracepoints and
433 ARM Symbian arm*-*-symbianelf*
435 * D language support.
436 GDB now supports debugging programs written in the D programming
439 * GDB now supports the extended ptrace interface for PowerPC which is
440 available since Linux kernel version 2.6.34. This automatically enables
441 any hardware breakpoints and additional hardware watchpoints available in
442 the processor. The old ptrace interface exposes just one hardware
443 watchpoint and no hardware breakpoints.
445 * GDB is now able to use the Data Value Compare (DVC) register available on
446 embedded PowerPC processors to implement in hardware simple watchpoint
447 conditions of the form:
449 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
451 This works in native GDB running on Linux kernels with the extended ptrace
452 interface mentioned above.
454 *** Changes in GDB 7.1
460 GDB now supports importing of namespaces in C++. This enables the
461 user to inspect variables from imported namespaces. Support for
462 namepace aliasing has also been added. So, if a namespace is
463 aliased in the current scope (e.g. namepace C=A; ) the user can
464 print variables using the alias (e.g. (gdb) print C::x).
468 All known bugs relating to the printing of virtual base class were
469 fixed. It is now possible to call overloaded static methods using a
474 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
475 and reinterpret_cast<> are now handled by the C++ expression parser.
479 Xilinx MicroBlaze microblaze-*-*
484 Xilinx MicroBlaze microblaze
487 * Multi-program debugging.
489 GDB now has support for multi-program (a.k.a. multi-executable or
490 multi-exec) debugging. This allows for debugging multiple inferiors
491 simultaneously each running a different program under the same GDB
492 session. See "Debugging Multiple Inferiors and Programs" in the
493 manual for more information. This implied some user visible changes
494 in the multi-inferior support. For example, "info inferiors" now
495 lists inferiors that are not running yet or that have exited
496 already. See also "New commands" and "New options" below.
498 * New tracing features
500 GDB's tracepoint facility now includes several new features:
502 ** Trace state variables
504 GDB tracepoints now include support for trace state variables, which
505 are variables managed by the target agent during a tracing
506 experiment. They are useful for tracepoints that trigger each
507 other, so for instance one tracepoint can count hits in a variable,
508 and then a second tracepoint has a condition that is true when the
509 count reaches a particular value. Trace state variables share the
510 $-syntax of GDB convenience variables, and can appear in both
511 tracepoint actions and condition expressions. Use the "tvariable"
512 command to create, and "info tvariables" to view; see "Trace State
513 Variables" in the manual for more detail.
517 GDB now includes an option for defining fast tracepoints, which
518 targets may implement more efficiently, such as by installing a jump
519 into the target agent rather than a trap instruction. The resulting
520 speedup can be by two orders of magnitude or more, although the
521 tradeoff is that some program locations on some target architectures
522 might not allow fast tracepoint installation, for instance if the
523 instruction to be replaced is shorter than the jump. To request a
524 fast tracepoint, use the "ftrace" command, with syntax identical to
525 the regular trace command.
527 ** Disconnected tracing
529 It is now possible to detach GDB from the target while it is running
530 a trace experiment, then reconnect later to see how the experiment
531 is going. In addition, a new variable disconnected-tracing lets you
532 tell the target agent whether to continue running a trace if the
533 connection is lost unexpectedly.
537 GDB now has the ability to save the trace buffer into a file, and
538 then use that file as a target, similarly to you can do with
539 corefiles. You can select trace frames, print data that was
540 collected in them, and use tstatus to display the state of the
541 tracing run at the moment that it was saved. To create a trace
542 file, use "tsave <filename>", and to use it, do "target tfile
545 ** Circular trace buffer
547 You can ask the target agent to handle the trace buffer as a
548 circular buffer, discarding the oldest trace frames to make room for
549 newer ones, by setting circular-trace-buffer to on. This feature may
550 not be available for all target agents.
555 The disassemble command, when invoked with two arguments, now requires
556 the arguments to be comma-separated.
559 The info variables command now displays variable definitions. Files
560 which only declare a variable are not shown.
563 The source command is now capable of sourcing Python scripts.
564 This feature is dependent on the debugger being build with Python
567 Related to this enhancement is also the introduction of a new command
568 "set script-extension" (see below).
570 * New commands (for set/show, see "New options" below)
572 record save [<FILENAME>]
573 Save a file (in core file format) containing the process record
574 execution log for replay debugging at a later time.
576 record restore <FILENAME>
577 Restore the process record execution log that was saved at an
578 earlier time, for replay debugging.
580 add-inferior [-copies <N>] [-exec <FILENAME>]
583 clone-inferior [-copies <N>] [ID]
584 Make a new inferior ready to execute the same program another
590 maint info program-spaces
591 List the program spaces loaded into GDB.
593 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
594 show remote interrupt-sequence
595 Allow the user to select one of ^C, a BREAK signal or BREAK-g
596 as the sequence to the remote target in order to interrupt the execution.
597 Ctrl-C is a default. Some system prefers BREAK which is high level of
598 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
599 Magic SysRq g. It is BREAK signal and character 'g'.
601 set remote interrupt-on-connect [on | off]
602 show remote interrupt-on-connect
603 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
604 remote target when gdb connects to it. This is needed when you debug
607 set remotebreak [on | off]
609 Deprecated. Use "set/show remote interrupt-sequence" instead.
611 tvariable $NAME [ = EXP ]
612 Create or modify a trace state variable.
615 List trace state variables and their values.
617 delete tvariable $NAME ...
618 Delete one or more trace state variables.
621 Evaluate the given expressions without collecting anything into the
622 trace buffer. (Valid in tracepoint actions only.)
624 ftrace FN / FILE:LINE / *ADDR
625 Define a fast tracepoint at the given function, line, or address.
627 * New expression syntax
629 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
630 GDB now parses 0b101010 identically with 42.
634 set follow-exec-mode new|same
635 show follow-exec-mode
636 Control whether GDB reuses the same inferior across an exec call or
637 creates a new one. This is useful to be able to restart the old
638 executable after the inferior having done an exec call.
640 set default-collect EXPR, ...
642 Define a list of expressions to be collected at each tracepoint.
643 This is a useful way to ensure essential items are not overlooked,
644 such as registers or a critical global variable.
646 set disconnected-tracing
647 show disconnected-tracing
648 If set to 1, the target is instructed to continue tracing if it
649 loses its connection to GDB. If 0, the target is to stop tracing
652 set circular-trace-buffer
653 show circular-trace-buffer
654 If set to on, the target is instructed to use a circular trace buffer
655 and discard the oldest trace frames instead of stopping the trace due
656 to a full trace buffer. If set to off, the trace stops when the buffer
657 fills up. Some targets may not support this.
659 set script-extension off|soft|strict
660 show script-extension
661 If set to "off", the debugger does not perform any script language
662 recognition, and all sourced files are assumed to be GDB scripts.
663 If set to "soft" (the default), files are sourced according to
664 filename extension, falling back to GDB scripts if the first
666 If set to "strict", files are sourced according to filename extension.
668 set ada trust-PAD-over-XVS on|off
669 show ada trust-PAD-over-XVS
670 If off, activate a workaround against a bug in the debugging information
671 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
672 the GCC sources for more information about the GNAT encoding and
673 PAD types in particular). It is always safe to set this option to
674 off, but this introduces a slight performance penalty. The default
677 * Python API Improvements
679 ** GDB provides the new class gdb.LazyString. This is useful in
680 some pretty-printing cases. The new method gdb.Value.lazy_string
681 provides a simple way to create objects of this type.
683 ** The fields returned by gdb.Type.fields now have an
684 `is_base_class' attribute.
686 ** The new method gdb.Type.range returns the range of an array type.
688 ** The new method gdb.parse_and_eval can be used to parse and
689 evaluate an expression.
694 Define a trace state variable.
697 Get the current value of a trace state variable.
700 Set desired tracing behavior upon disconnection.
703 Set the trace buffer to be linear or circular.
706 Get data about the tracepoints currently in use.
710 Process record now works correctly with hardware watchpoints.
712 Multiple bug fixes have been made to the mips-irix port, making it
713 much more reliable. In particular:
714 - Debugging threaded applications is now possible again. Previously,
715 GDB would hang while starting the program, or while waiting for
716 the program to stop at a breakpoint.
717 - Attaching to a running process no longer hangs.
718 - An error occurring while loading a core file has been fixed.
719 - Changing the value of the PC register now works again. This fixes
720 problems observed when using the "jump" command, or when calling
721 a function from GDB, or even when assigning a new value to $pc.
722 - With the "finish" and "return" commands, the return value for functions
723 returning a small array is now correctly printed.
724 - It is now possible to break on shared library code which gets executed
725 during a shared library init phase (code executed while executing
726 their .init section). Previously, the breakpoint would have no effect.
727 - GDB is now able to backtrace through the signal handler for
728 non-threaded programs.
730 PIE (Position Independent Executable) programs debugging is now supported.
731 This includes debugging execution of PIC (Position Independent Code) shared
732 libraries although for that, it should be possible to run such libraries as an
735 *** Changes in GDB 7.0
737 * GDB now has an interface for JIT compilation. Applications that
738 dynamically generate code can create symbol files in memory and register
739 them with GDB. For users, the feature should work transparently, and
740 for JIT developers, the interface is documented in the GDB manual in the
741 "JIT Compilation Interface" chapter.
743 * Tracepoints may now be conditional. The syntax is as for
744 breakpoints; either an "if" clause appended to the "trace" command,
745 or the "condition" command is available. GDB sends the condition to
746 the target for evaluation using the same bytecode format as is used
747 for tracepoint actions.
749 * The disassemble command now supports: an optional /r modifier, print the
750 raw instructions in hex as well as in symbolic form, and an optional /m
751 modifier to print mixed source+assembly.
753 * Process record and replay
755 In a architecture environment that supports ``process record and
756 replay'', ``process record and replay'' target can record a log of
757 the process execution, and replay it with both forward and reverse
760 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
761 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
762 set execution-direction {forward|reverse}, for targets that support
765 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
766 feature is available with a native GDB running on kernel version
769 * GDB now has support for multi-byte and wide character sets on the
770 target. Strings whose character type is wchar_t, char16_t, or
771 char32_t are now correctly printed. GDB supports wide- and unicode-
772 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
773 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
774 `printf'. This feature requires iconv to work properly; if your
775 system does not have a working iconv, GDB can use GNU libiconv. See
776 the installation instructions for more information.
778 * GDB now supports automatic retrieval of shared library files from
779 remote targets. To use this feature, specify a system root that begins
780 with the `remote:' prefix, either via the `set sysroot' command or via
781 the `--with-sysroot' configure-time option.
783 * "info sharedlibrary" now takes an optional regex of libraries to show,
784 and it now reports if a shared library has no debugging information.
786 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
787 now complete on file names.
789 * When completing in expressions, gdb will attempt to limit
790 completions to allowable structure or union fields, where appropriate.
791 For instance, consider:
793 # struct example { int f1; double f2; };
794 # struct example variable;
797 If the user types TAB at the end of this command line, the available
798 completions will be "f1" and "f2".
800 * Inlined functions are now supported. They show up in backtraces, and
801 the "step", "next", and "finish" commands handle them automatically.
803 * GDB now supports the token-splicing (##) and stringification (#)
804 operators when expanding macros. It also supports variable-arity
807 * GDB now supports inspecting extra signal information, exported by
808 the new $_siginfo convenience variable. The feature is currently
809 implemented on linux ARM, i386 and amd64.
811 * GDB can now display the VFP floating point registers and NEON vector
812 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
813 can provide these registers (requires Linux 2.6.30 or later). Remote
814 and simulator targets may also provide them.
819 Search memory for a sequence of bytes.
822 Turn off `+'/`-' protocol acknowledgments to permit more efficient
823 operation over reliable transport links. Use of this packet is
824 controlled by the `set remote noack-packet' command.
827 Kill the process with the specified process ID. Use this in preference
828 to `k' when multiprocess protocol extensions are supported.
831 Obtains additional operating system information
835 Read or write additional signal information.
837 * Removed remote protocol undocumented extension
839 An undocumented extension to the remote protocol's `S' stop reply
840 packet that permited the stub to pass a process id was removed.
841 Remote servers should use the `T' stop reply packet instead.
843 * GDB now supports multiple function calling conventions according to the
844 DWARF-2 DW_AT_calling_convention function attribute.
846 * The SH target utilizes the aforementioned change to distinguish between gcc
847 and Renesas calling convention. It also adds the new CLI commands
848 `set/show sh calling-convention'.
850 * GDB can now read compressed debug sections, as produced by GNU gold
851 with the --compress-debug-sections=zlib flag.
853 * 64-bit core files are now supported on AIX.
855 * Thread switching is now supported on Tru64.
857 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
858 which will be allocated using malloc later in program execution.
860 * The qXfer:libraries:read remote procotol packet now allows passing a
861 list of section offsets.
863 * On GNU/Linux, GDB can now attach to stopped processes. Several race
864 conditions handling signals delivered during attach or thread creation
865 have also been fixed.
867 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
868 From the user's standpoint, all unqualified instances of True and False
869 are treated as the standard definitions, regardless of context.
871 * GDB now parses C++ symbol and type names more flexibly. For
874 template<typename T> class C { };
877 GDB will now correctly handle all of:
879 ptype C<char const *>
881 ptype C<const char *>
884 * New features in the GDB remote stub, gdbserver
886 - The "--wrapper" command-line argument tells gdbserver to use a
887 wrapper program to launch programs for debugging.
889 - On PowerPC and S/390 targets, it is now possible to use a single
890 gdbserver executable to debug both 32-bit and 64-bit programs.
891 (This requires gdbserver itself to be built as a 64-bit executable.)
893 - gdbserver uses the new noack protocol mode for TCP connections to
894 reduce communications latency, if also supported and enabled in GDB.
896 - Support for the sparc64-linux-gnu target is now included in
899 - The amd64-linux build of gdbserver now supports debugging both
900 32-bit and 64-bit programs.
902 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
903 now support hardware watchpoints, and will use them automatically
908 GDB now has support for scripting using Python. Whether this is
909 available is determined at configure time.
911 New GDB commands can now be written in Python.
913 * Ada tasking support
915 Ada tasks can now be inspected in GDB. The following commands have
919 Print the list of Ada tasks.
921 Print detailed information about task number N.
923 Print the task number of the current task.
925 Switch the context of debugging to task number N.
927 * Support for user-defined prefixed commands. The "define" command can
928 add new commands to existing prefixes, e.g. "target".
930 * Multi-inferior, multi-process debugging.
932 GDB now has generalized support for multi-inferior debugging. See
933 "Debugging Multiple Inferiors" in the manual for more information.
934 Although availability still depends on target support, the command
935 set is more uniform now. The GNU/Linux specific multi-forks support
936 has been migrated to this new framework. This implied some user
937 visible changes; see "New commands" and also "Removed commands"
940 * Target descriptions can now describe the target OS ABI. See the
941 "Target Description Format" section in the user manual for more
944 * Target descriptions can now describe "compatible" architectures
945 to indicate that the target can execute applications for a different
946 architecture in addition to those for the main target architecture.
947 See the "Target Description Format" section in the user manual for
950 * Multi-architecture debugging.
952 GDB now includes general supports for debugging applications on
953 hybrid systems that use more than one single processor architecture
954 at the same time. Each such hybrid architecture still requires
955 specific support to be added. The only hybrid architecture supported
956 in this version of GDB is the Cell Broadband Engine.
958 * GDB now supports integrated debugging of Cell/B.E. applications that
959 use both the PPU and SPU architectures. To enable support for hybrid
960 Cell/B.E. debugging, you need to configure GDB to support both the
961 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
962 --enable-targets configure option.
964 * Non-stop mode debugging.
966 For some targets, GDB now supports an optional mode of operation in
967 which you can examine stopped threads while other threads continue
968 to execute freely. This is referred to as non-stop mode, with the
969 old mode referred to as all-stop mode. See the "Non-Stop Mode"
970 section in the user manual for more information.
972 To be able to support remote non-stop debugging, a remote stub needs
973 to implement the non-stop mode remote protocol extensions, as
974 described in the "Remote Non-Stop" section of the user manual. The
975 GDB remote stub, gdbserver, has been adjusted to support these
976 extensions on linux targets.
978 * New commands (for set/show, see "New options" below)
980 catch syscall [NAME(S) | NUMBER(S)]
981 Catch system calls. Arguments, which should be names of system
982 calls or their numbers, mean catch only those syscalls. Without
983 arguments, every syscall will be caught. When the inferior issues
984 any of the specified syscalls, GDB will stop and announce the system
985 call, both when it is called and when its call returns. This
986 feature is currently available with a native GDB running on the
987 Linux Kernel, under the following architectures: x86, x86_64,
988 PowerPC and PowerPC64.
990 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
992 Search memory for a sequence of bytes.
994 maint set python print-stack
995 maint show python print-stack
996 Show a stack trace when an error is encountered in a Python script.
999 Invoke CODE by passing it to the Python interpreter.
1004 These allow macros to be defined, undefined, and listed
1008 Show operating system information about processes.
1011 List the inferiors currently under GDB's control.
1014 Switch focus to inferior number NUM.
1017 Detach from inferior number NUM.
1020 Kill inferior number NUM.
1024 set spu stop-on-load
1025 show spu stop-on-load
1026 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1028 set spu auto-flush-cache
1029 show spu auto-flush-cache
1030 Control whether to automatically flush the software-managed cache
1031 during Cell/B.E. debugging.
1033 set sh calling-convention
1034 show sh calling-convention
1035 Control the calling convention used when calling SH target functions.
1038 show debug timestamp
1039 Control display of timestamps with GDB debugging output.
1041 set disassemble-next-line
1042 show disassemble-next-line
1043 Control display of disassembled source lines or instructions when
1046 set remote noack-packet
1047 show remote noack-packet
1048 Set/show the use of remote protocol QStartNoAckMode packet. See above
1049 under "New remote packets."
1051 set remote query-attached-packet
1052 show remote query-attached-packet
1053 Control use of remote protocol `qAttached' (query-attached) packet.
1055 set remote read-siginfo-object
1056 show remote read-siginfo-object
1057 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1060 set remote write-siginfo-object
1061 show remote write-siginfo-object
1062 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1065 set remote reverse-continue
1066 show remote reverse-continue
1067 Control use of remote protocol 'bc' (reverse-continue) packet.
1069 set remote reverse-step
1070 show remote reverse-step
1071 Control use of remote protocol 'bs' (reverse-step) packet.
1073 set displaced-stepping
1074 show displaced-stepping
1075 Control displaced stepping mode. Displaced stepping is a way to
1076 single-step over breakpoints without removing them from the debuggee.
1077 Also known as "out-of-line single-stepping".
1080 show debug displaced
1081 Control display of debugging info for displaced stepping.
1083 maint set internal-error
1084 maint show internal-error
1085 Control what GDB does when an internal error is detected.
1087 maint set internal-warning
1088 maint show internal-warning
1089 Control what GDB does when an internal warning is detected.
1094 Use a wrapper program to launch programs for debugging.
1096 set multiple-symbols (all|ask|cancel)
1097 show multiple-symbols
1098 The value of this variable can be changed to adjust the debugger behavior
1099 when an expression or a breakpoint location contains an ambiguous symbol
1100 name (an overloaded function name, for instance).
1102 set breakpoint always-inserted
1103 show breakpoint always-inserted
1104 Keep breakpoints always inserted in the target, as opposed to inserting
1105 them when resuming the target, and removing them when the target stops.
1106 This option can improve debugger performance on slow remote targets.
1108 set arm fallback-mode (arm|thumb|auto)
1109 show arm fallback-mode
1110 set arm force-mode (arm|thumb|auto)
1112 These commands control how ARM GDB determines whether instructions
1113 are ARM or Thumb. The default for both settings is auto, which uses
1114 the current CPSR value for instructions without symbols; previous
1115 versions of GDB behaved as if "set arm fallback-mode arm".
1117 set disable-randomization
1118 show disable-randomization
1119 Standalone programs run with the virtual address space randomization enabled
1120 by default on some platforms. This option keeps the addresses stable across
1121 multiple debugging sessions.
1125 Control whether other threads are stopped or not when some thread hits
1130 Requests that asynchronous execution is enabled in the target, if available.
1131 In this case, it's possible to resume target in the background, and interact
1132 with GDB while the target is running. "show target-async" displays the
1133 current state of asynchronous execution of the target.
1135 set target-wide-charset
1136 show target-wide-charset
1137 The target-wide-charset is the name of the character set that GDB
1138 uses when printing characters whose type is wchar_t.
1140 set tcp auto-retry (on|off)
1142 set tcp connect-timeout
1143 show tcp connect-timeout
1144 These commands allow GDB to retry failed TCP connections to a remote stub
1145 with a specified timeout period; this is useful if the stub is launched
1146 in parallel with GDB but may not be ready to accept connections immediately.
1148 set libthread-db-search-path
1149 show libthread-db-search-path
1150 Control list of directories which GDB will search for appropriate
1153 set schedule-multiple (on|off)
1154 show schedule-multiple
1155 Allow GDB to resume all threads of all processes or only threads of
1156 the current process.
1160 Use more aggressive caching for accesses to the stack. This improves
1161 performance of remote debugging (particularly backtraces) without
1162 affecting correctness.
1164 set interactive-mode (on|off|auto)
1165 show interactive-mode
1166 Control whether GDB runs in interactive mode (on) or not (off).
1167 When in interactive mode, GDB waits for the user to answer all
1168 queries. Otherwise, GDB does not wait and assumes the default
1169 answer. When set to auto (the default), GDB determines which
1170 mode to use based on the stdin settings.
1175 For program forks, this is replaced by the new more generic `info
1176 inferiors' command. To list checkpoints, you can still use the
1177 `info checkpoints' command, which was an alias for the `info forks'
1181 Replaced by the new `inferior' command. To switch between
1182 checkpoints, you can still use the `restart' command, which was an
1183 alias for the `fork' command.
1186 This is removed, since some targets don't have a notion of
1187 processes. To switch between processes, you can still use the
1188 `inferior' command using GDB's own inferior number.
1191 For program forks, this is replaced by the new more generic `kill
1192 inferior' command. To delete a checkpoint, you can still use the
1193 `delete checkpoint' command, which was an alias for the `delete
1197 For program forks, this is replaced by the new more generic `detach
1198 inferior' command. To detach a checkpoint, you can still use the
1199 `detach checkpoint' command, which was an alias for the `detach
1202 * New native configurations
1204 x86/x86_64 Darwin i[34567]86-*-darwin*
1206 x86_64 MinGW x86_64-*-mingw*
1210 Lattice Mico32 lm32-*
1211 x86 DICOS i[34567]86-*-dicos*
1212 x86_64 DICOS x86_64-*-dicos*
1215 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1216 (mingw32ce) debugging.
1222 These commands were actually not implemented on any target.
1224 *** Changes in GDB 6.8
1226 * New native configurations
1228 NetBSD/hppa hppa*-*netbsd*
1229 Xtensa GNU/Linux xtensa*-*-linux*
1233 NetBSD/hppa hppa*-*-netbsd*
1234 Xtensa GNU/Lunux xtensa*-*-linux*
1236 * Change in command line behavior -- corefiles vs. process ids.
1238 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1239 attaching to process NUMBER fails, GDB no longer attempts to open a
1240 core file named NUMBER. Attaching to a program using the -c option
1241 is no longer supported. Instead, use the '-p' or '--pid' options.
1243 * GDB can now be built as a native debugger for debugging Windows x86
1244 (mingw32) Portable Executable (PE) programs.
1246 * Pending breakpoints no longer change their number when their address
1249 * GDB now supports breakpoints with multiple locations,
1250 including breakpoints on C++ constructors, inside C++ templates,
1251 and in inlined functions.
1253 * GDB's ability to debug optimized code has been improved. GDB more
1254 accurately identifies function bodies and lexical blocks that occupy
1255 more than one contiguous range of addresses.
1257 * Target descriptions can now describe registers for PowerPC.
1259 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1260 registers on PowerPC targets.
1262 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1263 targets even when the libthread_db library is not available.
1265 * The GDB remote stub, gdbserver, now supports the new file transfer
1266 commands (remote put, remote get, and remote delete).
1268 * The GDB remote stub, gdbserver, now supports run and attach in
1269 extended-remote mode.
1271 * hppa*64*-*-hpux11* target broken
1272 The debugger is unable to start a program and fails with the following
1273 error: "Error trying to get information about dynamic linker".
1274 The gdb-6.7 release is also affected.
1276 * GDB now supports the --enable-targets= configure option to allow
1277 building a single GDB executable that supports multiple remote
1278 target architectures.
1280 * GDB now supports debugging C and C++ programs which use the
1281 Decimal Floating Point extension. In addition, the PowerPC target
1282 now has a set of pseudo-registers to inspect decimal float values
1283 stored in two consecutive float registers.
1285 * The -break-insert MI command can optionally create pending
1288 * Improved support for debugging Ada
1289 Many improvements to the Ada language support have been made. These
1291 - Better support for Ada2005 interface types
1292 - Improved handling of arrays and slices in general
1293 - Better support for Taft-amendment types
1294 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1296 - Improved command completion in Ada
1299 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1304 set print frame-arguments (all|scalars|none)
1305 show print frame-arguments
1306 The value of this variable can be changed to control which argument
1307 values should be printed by the debugger when displaying a frame.
1312 Transfer files to and from a remote target, and delete remote files.
1319 Transfer files to and from a remote target, and delete remote files.
1321 * New remote packets
1328 Open, close, read, write, and delete files on the remote system.
1331 Attach to an existing process on the remote system, in extended-remote
1335 Run a new process on the remote system, in extended-remote mode.
1337 *** Changes in GDB 6.7
1339 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1340 bfd, libiberty and opcodes, as revealed by static analysis donated by
1341 Coverity, Inc. (http://scan.coverity.com).
1343 * When looking up multiply-defined global symbols, GDB will now prefer the
1344 symbol definition in the current shared library if it was built using the
1345 -Bsymbolic linker option.
1347 * When the Text User Interface (TUI) is not configured, GDB will now
1348 recognize the -tui command-line option and print a message that the TUI
1351 * The GDB remote stub, gdbserver, now has lower overhead for high
1352 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1354 * GDB for MIPS targets now autodetects whether a remote target provides
1355 32-bit or 64-bit register values.
1357 * Support for C++ member pointers has been improved.
1359 * GDB now understands XML target descriptions, which specify the
1360 target's overall architecture. GDB can read a description from
1361 a local file or over the remote serial protocol.
1363 * Vectors of single-byte data use a new integer type which is not
1364 automatically displayed as character or string data.
1366 * The /s format now works with the print command. It displays
1367 arrays of single-byte integers and pointers to single-byte integers
1370 * Target descriptions can now describe target-specific registers,
1371 for architectures which have implemented the support (currently
1372 only ARM, M68K, and MIPS).
1374 * GDB and the GDB remote stub, gdbserver, now support the XScale
1377 * The GDB remote stub, gdbserver, has been updated to support
1378 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1379 has been rewritten to use the standard GDB remote protocol.
1381 * GDB can now step into C++ functions which are called through thunks.
1383 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1385 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1386 layout. It also supports a TextSeg= and DataSeg= response when only
1387 segment base addresses (rather than offsets) are available.
1389 * The /i format now outputs any trailing branch delay slot instructions
1390 immediately following the last instruction within the count specified.
1392 * The GDB remote protocol "T" stop reply packet now supports a
1393 "library" response. Combined with the new "qXfer:libraries:read"
1394 packet, this response allows GDB to debug shared libraries on targets
1395 where the operating system manages the list of loaded libraries (e.g.
1396 Windows and SymbianOS).
1398 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1399 (DLLs) on Windows and Windows CE targets.
1401 * GDB now supports a faster verification that a .debug file matches its binary
1402 according to its build-id signature, if the signature is present.
1408 Enable or disable hardware flow control (RTS/CTS) on the serial port
1409 when debugging using remote targets.
1411 set mem inaccessible-by-default
1412 show mem inaccessible-by-default
1413 If the target supplies a memory map, for instance via the remote
1414 protocol's "qXfer:memory-map:read" packet, setting this variable
1415 prevents GDB from accessing memory outside the memory map. This
1416 is useful for targets with memory mapped registers or which react
1417 badly to accesses of unmapped address space.
1419 set breakpoint auto-hw
1420 show breakpoint auto-hw
1421 If the target supplies a memory map, for instance via the remote
1422 protocol's "qXfer:memory-map:read" packet, setting this variable
1423 lets GDB use hardware breakpoints automatically for memory regions
1424 where it can not use software breakpoints. This covers both the
1425 "break" command and internal breakpoints used for other commands
1426 including "next" and "finish".
1429 catch exception unhandled
1430 Stop the program execution when Ada exceptions are raised.
1433 Stop the program execution when an Ada assertion failed.
1437 Set an alternate system root for target files. This is a more
1438 general version of "set solib-absolute-prefix", which is now
1439 an alias to "set sysroot".
1442 Provide extended SPU facility status information. This set of
1443 commands is available only when debugging the Cell/B.E. SPU
1446 * New native configurations
1448 OpenBSD/sh sh*-*openbsd*
1451 unset tdesc filename
1453 Use the specified local file as an XML target description, and do
1454 not query the target for its built-in description.
1458 OpenBSD/sh sh*-*-openbsd*
1459 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1460 Toshiba Media Processor mep-elf
1462 * New remote packets
1465 Ignore the specified signals; pass them directly to the debugged program
1466 without stopping other threads or reporting them to GDB.
1468 qXfer:features:read:
1469 Read an XML target description from the target, which describes its
1474 Read or write contents of an spufs file on the target system. These
1475 packets are available only on the Cell/B.E. SPU architecture.
1477 qXfer:libraries:read:
1478 Report the loaded shared libraries. Combined with new "T" packet
1479 response, this packet allows GDB to debug shared libraries on
1480 targets where the operating system manages the list of loaded
1481 libraries (e.g. Windows and SymbianOS).
1485 Support for these obsolete configurations has been removed.
1493 i[34567]86-*-lynxos*
1494 i[34567]86-*-netware*
1495 i[34567]86-*-sco3.2v5*
1496 i[34567]86-*-sco3.2v4*
1498 i[34567]86-*-sysv4.2*
1501 i[34567]86-*-unixware2*
1502 i[34567]86-*-unixware*
1511 * Other removed features
1518 Various m68k-only ROM monitors.
1525 Various Renesas ROM monitors and debugging interfaces for SH and
1530 Support for a Macraigor serial interface to on-chip debugging.
1531 GDB does not directly support the newer parallel or USB
1536 A debug information format. The predecessor to DWARF 2 and
1537 DWARF 3, which are still supported.
1539 Support for the HP aCC compiler on HP-UX/PA-RISC
1541 SOM-encapsulated symbolic debugging information, automatic
1542 invocation of pxdb, and the aCC custom C++ ABI. This does not
1543 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1544 with aCC can still be debugged on an assembly level.
1546 MIPS ".pdr" sections
1548 A MIPS-specific format used to describe stack frame layout
1549 in debugging information.
1553 GDB could work with an older version of Guile to debug
1554 the interpreter and Scheme programs running in it.
1556 set mips stack-arg-size
1557 set mips saved-gpreg-size
1559 Use "set mips abi" to control parameter passing for MIPS.
1561 *** Changes in GDB 6.6
1566 Cell Broadband Engine SPU spu-elf
1568 * GDB can now be configured as a cross-debugger targeting native Windows
1569 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1570 running on a Windows system over TCP/IP to debug Windows programs.
1572 * The GDB remote stub, gdbserver, has been updated to support Windows and
1573 Cygwin debugging. Both single-threaded and multi-threaded programs are
1576 * The "set trust-readonly-sections" command works again. This command was
1577 broken in GDB 6.3, 6.4, and 6.5.
1579 * The "load" command now supports writing to flash memory, if the remote
1580 stub provides the required support.
1582 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1583 longer requires symbolic debug information (e.g. DWARF-2).
1588 unset substitute-path
1589 show substitute-path
1590 Manage a list of substitution rules that GDB uses to rewrite the name
1591 of the directories where the sources are located. This can be useful
1592 for instance when the sources were moved to a different location
1593 between compilation and debugging.
1597 Print each CLI command as it is executed. Each command is prefixed with
1598 a number of `+' symbols representing the nesting depth.
1599 The source command now has a `-v' option to enable the same feature.
1603 The ARM Demon monitor support (RDP protocol, "target rdp").
1605 Kernel Object Display, an embedded debugging feature which only worked with
1606 an obsolete version of Cisco IOS.
1608 The 'set download-write-size' and 'show download-write-size' commands.
1610 * New remote packets
1613 Tell a stub about GDB client features, and request remote target features.
1614 The first feature implemented is PacketSize, which allows the target to
1615 specify the size of packets it can handle - to minimize the number of
1616 packets required and improve performance when connected to a remote
1620 Fetch an OS auxilliary vector from the remote stub. This packet is a
1621 more efficient replacement for qPart:auxv:read.
1623 qXfer:memory-map:read:
1624 Fetch a memory map from the remote stub, including information about
1625 RAM, ROM, and flash memory devices.
1630 Erase and program a flash memory device.
1632 * Removed remote packets
1635 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1636 used it, and only gdbserver implemented it.
1638 *** Changes in GDB 6.5
1642 Renesas M32C/M16C m32c-elf
1644 Morpho Technologies ms1 ms1-elf
1648 init-if-undefined Initialize a convenience variable, but
1649 only if it doesn't already have a value.
1651 The following commands are presently only implemented for native GNU/Linux:
1653 checkpoint Save a snapshot of the program state.
1655 restart <n> Return the program state to a
1656 previously saved state.
1658 info checkpoints List currently saved checkpoints.
1660 delete-checkpoint <n> Delete a previously saved checkpoint.
1662 set|show detach-on-fork Tell gdb whether to detach from a newly
1663 forked process, or to keep debugging it.
1665 info forks List forks of the user program that
1666 are available to be debugged.
1668 fork <n> Switch to debugging one of several
1669 forks of the user program that are
1670 available to be debugged.
1672 delete-fork <n> Delete a fork from the list of forks
1673 that are available to be debugged (and
1674 kill the forked process).
1676 detach-fork <n> Delete a fork from the list of forks
1677 that are available to be debugged (and
1678 allow the process to continue).
1682 Morpho Technologies ms2 ms1-elf
1684 * Improved Windows host support
1686 GDB now builds as a cross debugger hosted on i686-mingw32, including
1687 native console support, and remote communications using either
1688 network sockets or serial ports.
1690 * Improved Modula-2 language support
1692 GDB can now print most types in the Modula-2 syntax. This includes:
1693 basic types, set types, record types, enumerated types, range types,
1694 pointer types and ARRAY types. Procedure var parameters are correctly
1695 printed and hexadecimal addresses and character constants are also
1696 written in the Modula-2 syntax. Best results can be obtained by using
1697 GNU Modula-2 together with the -gdwarf-2 command line option.
1701 The ARM rdi-share module.
1703 The Netware NLM debug server.
1705 *** Changes in GDB 6.4
1707 * New native configurations
1709 OpenBSD/arm arm*-*-openbsd*
1710 OpenBSD/mips64 mips64-*-openbsd*
1714 Morpho Technologies ms1 ms1-elf
1716 * New command line options
1718 --batch-silent As for --batch, but totally silent.
1719 --return-child-result The debugger will exist with the same value
1720 the child (debugged) program exited with.
1721 --eval-command COMMAND, -ex COMMAND
1722 Execute a single GDB CLI command. This may be
1723 specified multiple times and in conjunction
1724 with the --command (-x) option.
1726 * Deprecated commands removed
1728 The following commands, that were deprecated in 2000, have been
1732 set|show arm disassembly-flavor set|show arm disassembler
1733 othernames set arm disassembler
1734 set|show remotedebug set|show debug remote
1735 set|show archdebug set|show debug arch
1736 set|show eventdebug set|show debug event
1739 * New BSD user-level threads support
1741 It is now possible to debug programs using the user-level threads
1742 library on OpenBSD and FreeBSD. Currently supported (target)
1745 FreeBSD/amd64 x86_64-*-freebsd*
1746 FreeBSD/i386 i386-*-freebsd*
1747 OpenBSD/i386 i386-*-openbsd*
1749 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1750 are not yet supported.
1752 * New support for Matsushita MN10300 w/sim added
1753 (Work in progress). mn10300-elf.
1755 * REMOVED configurations and files
1757 VxWorks and the XDR protocol *-*-vxworks
1758 Motorola MCORE mcore-*-*
1759 National Semiconductor NS32000 ns32k-*-*
1761 * New "set print array-indexes" command
1763 After turning this setting "on", GDB prints the index of each element
1764 when displaying arrays. The default is "off" to preserve the previous
1767 * VAX floating point support
1769 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1771 * User-defined command support
1773 In addition to using $arg0..$arg9 for argument passing, it is now possible
1774 to use $argc to determine now many arguments have been passed. See the
1775 section on user-defined commands in the user manual for more information.
1777 *** Changes in GDB 6.3:
1779 * New command line option
1781 GDB now accepts -l followed by a number to set the timeout for remote
1784 * GDB works with GCC -feliminate-dwarf2-dups
1786 GDB now supports a more compact representation of DWARF-2 debug
1787 information using DW_FORM_ref_addr references. These are produced
1788 by GCC with the option -feliminate-dwarf2-dups and also by some
1789 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1790 to use -feliminate-dwarf2-dups.
1792 * Internationalization
1794 When supported by the host system, GDB will be built with
1795 internationalization (libintl). The task of marking up the sources is
1796 continued, we're looking forward to our first translation.
1800 Initial support for debugging programs compiled with the GNAT
1801 implementation of the Ada programming language has been integrated
1802 into GDB. In this release, support is limited to expression evaluation.
1804 * New native configurations
1806 GNU/Linux/m32r m32r-*-linux-gnu
1810 GDB's remote protocol now includes support for the 'p' packet. This
1811 packet is used to fetch individual registers from a remote inferior.
1813 * END-OF-LIFE registers[] compatibility module
1815 GDB's internal register infrastructure has been completely rewritten.
1816 The new infrastructure making possible the implementation of key new
1817 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1820 GDB 6.3 will be the last release to include the the registers[]
1821 compatibility module that allowed out-of-date configurations to
1822 continue to work. This change directly impacts the following
1832 powerpc bdm protocol
1834 Unless there is activity to revive these configurations, they will be
1835 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1837 * OBSOLETE configurations and files
1839 Configurations that have been declared obsolete in this release have
1840 been commented out. Unless there is activity to revive these
1841 configurations, the next release of GDB will have their sources
1842 permanently REMOVED.
1851 *** Changes in GDB 6.2.1:
1853 * MIPS `break main; run' gave an heuristic-fence-post warning
1855 When attempting to run even a simple program, a warning about
1856 heuristic-fence-post being hit would be reported. This problem has
1859 * MIPS IRIX 'long double' crashed GDB
1861 When examining a long double variable, GDB would get a segmentation
1862 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1863 IRIX long double values).
1867 A bug in the VAX stack code was causing problems with the "next"
1868 command. This problem has been fixed.
1870 *** Changes in GDB 6.2:
1872 * Fix for ``many threads''
1874 On GNU/Linux systems that use the NPTL threads library, a program
1875 rapidly creating and deleting threads would confuse GDB leading to the
1878 ptrace: No such process.
1879 thread_db_get_info: cannot get thread info: generic error
1881 This problem has been fixed.
1883 * "-async" and "-noasync" options removed.
1885 Support for the broken "-noasync" option has been removed (it caused
1888 * New ``start'' command.
1890 This command runs the program until the begining of the main procedure.
1892 * New BSD Kernel Data Access Library (libkvm) interface
1894 Using ``target kvm'' it is now possible to debug kernel core dumps and
1895 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1896 platforms. Currently supported (native-only) configurations are:
1898 FreeBSD/amd64 x86_64-*-freebsd*
1899 FreeBSD/i386 i?86-*-freebsd*
1900 NetBSD/i386 i?86-*-netbsd*
1901 NetBSD/m68k m68*-*-netbsd*
1902 NetBSD/sparc sparc-*-netbsd*
1903 OpenBSD/amd64 x86_64-*-openbsd*
1904 OpenBSD/i386 i?86-*-openbsd*
1905 OpenBSD/m68k m68*-openbsd*
1906 OpenBSD/sparc sparc-*-openbsd*
1908 * Signal trampoline code overhauled
1910 Many generic problems with GDB's signal handling code have been fixed.
1911 These include: backtraces through non-contiguous stacks; recognition
1912 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1913 call; backtrace through a signal trampoline; step into and out of
1914 signal handlers; and single-stepping in the signal trampoline.
1916 Please note that kernel bugs are a limiting factor here. These
1917 features have been shown to work on an s390 GNU/Linux system that
1918 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1920 * Cygwin support for DWARF 2 added.
1922 * New native configurations
1924 GNU/Linux/hppa hppa*-*-linux*
1925 OpenBSD/hppa hppa*-*-openbsd*
1926 OpenBSD/m68k m68*-*-openbsd*
1927 OpenBSD/m88k m88*-*-openbsd*
1928 OpenBSD/powerpc powerpc-*-openbsd*
1929 NetBSD/vax vax-*-netbsd*
1930 OpenBSD/vax vax-*-openbsd*
1932 * END-OF-LIFE frame compatibility module
1934 GDB's internal frame infrastructure has been completely rewritten.
1935 The new infrastructure making it possible to support key new features
1936 including DWARF 2 Call Frame Information. To aid in the task of
1937 migrating old configurations to this new infrastructure, a
1938 compatibility module, that allowed old configurations to continue to
1939 work, was also included.
1941 GDB 6.2 will be the last release to include this frame compatibility
1942 module. This change directly impacts the following configurations:
1952 Unless there is activity to revive these configurations, they will be
1953 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1955 * REMOVED configurations and files
1957 Sun 3, running SunOS 3 m68*-*-sunos3*
1958 Sun 3, running SunOS 4 m68*-*-sunos4*
1959 Sun 2, running SunOS 3 m68000-*-sunos3*
1960 Sun 2, running SunOS 4 m68000-*-sunos4*
1961 Motorola 680x0 running LynxOS m68*-*-lynxos*
1962 AT&T 3b1/Unix pc m68*-att-*
1963 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1964 decstation mips-dec-* mips-little-*
1965 riscos mips-*-riscos* mips-*-sysv*
1966 sonymips mips-sony-*
1967 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1969 *** Changes in GDB 6.1.1:
1971 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1973 The TUI (Text-mode User Interface) is now built as part of a default
1974 GDB configuration. It is enabled by either selecting the TUI with the
1975 command line option "-i=tui" or by running the separate "gdbtui"
1976 program. For more information on the TUI, see the manual "Debugging
1979 * Pending breakpoint support (also included in GDB 6.1)
1981 Support has been added to allow you to specify breakpoints in shared
1982 libraries that have not yet been loaded. If a breakpoint location
1983 cannot be found, and the "breakpoint pending" option is set to auto,
1984 GDB queries you if you wish to make the breakpoint pending on a future
1985 shared-library load. If and when GDB resolves the breakpoint symbol,
1986 the pending breakpoint is removed as one or more regular breakpoints
1989 Pending breakpoints are very useful for GCJ Java debugging.
1991 * Fixed ISO-C build problems
1993 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1994 non ISO-C code that stopped them being built using a more strict ISO-C
1995 compiler (e.g., IBM's C compiler).
1997 * Fixed build problem on IRIX 5
1999 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2000 wasn't able to compile compile on an IRIX 5 system.
2002 * Added execute permission to gdb/gdbserver/configure
2004 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2005 permission. This bug would cause configure to fail on a number of
2006 systems (Solaris, IRIX). Ref: server/519.
2008 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2010 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2011 has been updated to use constant array sizes.
2013 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2015 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2016 its generated DWARF Call Frame Info. This encoding was causing GDB to
2017 panic, that panic has been fixed. Ref: gdb/1628.
2019 * Fixed a problem when examining parameters in shared library code.
2021 When examining parameters in optimized shared library code generated
2022 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2023 not available''. GDB now correctly displays the variable's value.
2025 *** Changes in GDB 6.1:
2027 * Removed --with-mmalloc
2029 Support for the mmalloc memory manager has been removed, as it
2030 conflicted with the internal gdb byte cache.
2032 * Changes in AMD64 configurations
2034 The AMD64 target now includes the %cs and %ss registers. As a result
2035 the AMD64 remote protocol has changed; this affects the floating-point
2036 and SSE registers. If you rely on those registers for your debugging,
2037 you should upgrade gdbserver on the remote side.
2039 * Revised SPARC target
2041 The SPARC target has been completely revised, incorporating the
2042 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2043 support for LynxOS and SunOS 4 has been dropped. Calling functions
2044 from within GDB on operating systems with a non-executable stack
2045 (Solaris, OpenBSD) now works.
2049 GDB has a new C++ demangler which does a better job on the mangled
2050 names generated by current versions of g++. It also runs faster, so
2051 with this and other changes gdb should now start faster on large C++
2054 * DWARF 2 Location Expressions
2056 GDB support for location expressions has been extended to support function
2057 arguments and frame bases. Older versions of GDB could crash when they
2060 * C++ nested types and namespaces
2062 GDB's support for nested types and namespaces in C++ has been
2063 improved, especially if you use the DWARF 2 debugging format. (This
2064 is the default for recent versions of GCC on most platforms.)
2065 Specifically, if you have a class "Inner" defined within a class or
2066 namespace "Outer", then GDB realizes that the class's name is
2067 "Outer::Inner", not simply "Inner". This should greatly reduce the
2068 frequency of complaints about not finding RTTI symbols. In addition,
2069 if you are stopped at inside of a function defined within a namespace,
2070 GDB modifies its name lookup accordingly.
2072 * New native configurations
2074 NetBSD/amd64 x86_64-*-netbsd*
2075 OpenBSD/amd64 x86_64-*-openbsd*
2076 OpenBSD/alpha alpha*-*-openbsd*
2077 OpenBSD/sparc sparc-*-openbsd*
2078 OpenBSD/sparc64 sparc64-*-openbsd*
2080 * New debugging protocols
2082 M32R with SDI protocol m32r-*-elf*
2084 * "set prompt-escape-char" command deleted.
2086 The command "set prompt-escape-char" has been deleted. This command,
2087 and its very obscure effet on GDB's prompt, was never documented,
2088 tested, nor mentioned in the NEWS file.
2090 * OBSOLETE configurations and files
2092 Configurations that have been declared obsolete in this release have
2093 been commented out. Unless there is activity to revive these
2094 configurations, the next release of GDB will have their sources
2095 permanently REMOVED.
2097 Sun 3, running SunOS 3 m68*-*-sunos3*
2098 Sun 3, running SunOS 4 m68*-*-sunos4*
2099 Sun 2, running SunOS 3 m68000-*-sunos3*
2100 Sun 2, running SunOS 4 m68000-*-sunos4*
2101 Motorola 680x0 running LynxOS m68*-*-lynxos*
2102 AT&T 3b1/Unix pc m68*-att-*
2103 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2104 decstation mips-dec-* mips-little-*
2105 riscos mips-*-riscos* mips-*-sysv*
2106 sonymips mips-sony-*
2107 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2109 * REMOVED configurations and files
2111 SGI Irix-4.x mips-sgi-irix4 or iris4
2112 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2113 Z8000 simulator z8k-zilog-none or z8ksim
2114 Matsushita MN10200 w/simulator mn10200-*-*
2115 H8/500 simulator h8500-hitachi-hms or h8500hms
2116 HP/PA running BSD hppa*-*-bsd*
2117 HP/PA running OSF/1 hppa*-*-osf*
2118 HP/PA Pro target hppa*-*-pro*
2119 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2120 386BSD i[3456]86-*-bsd*
2121 Sequent family i[3456]86-sequent-sysv4*
2122 i[3456]86-sequent-sysv*
2123 i[3456]86-sequent-bsd*
2124 SPARC running LynxOS sparc-*-lynxos*
2125 SPARC running SunOS 4 sparc-*-sunos4*
2126 Tsqware Sparclet sparclet-*-*
2127 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2129 *** Changes in GDB 6.0:
2133 Support for debugging the Objective-C programming language has been
2134 integrated into GDB.
2136 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2138 DWARF 2's Call Frame Information makes available compiler generated
2139 information that more exactly describes the program's run-time stack.
2140 By using this information, GDB is able to provide more robust stack
2143 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2144 have been updated to use a new backtrace mechanism which includes
2145 DWARF 2 CFI support.
2149 GDB's remote protocol has been extended to include support for hosted
2150 file I/O (where the remote target uses GDB's file system). See GDB's
2151 remote protocol documentation for details.
2153 * All targets using the new architecture framework.
2155 All of GDB's targets have been updated to use the new internal
2156 architecture framework. The way is now open for future GDB releases
2157 to include cross-architecture native debugging support (i386 on amd64,
2160 * GNU/Linux's Thread Local Storage (TLS)
2162 GDB now includes support for for the GNU/Linux implementation of
2163 per-thread variables.
2165 * GNU/Linux's Native POSIX Thread Library (NPTL)
2167 GDB's thread code has been updated to work with either the new
2168 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2170 * Separate debug info.
2172 GDB, in conjunction with BINUTILS, now supports a mechanism for
2173 automatically loading debug information from a separate file. Instead
2174 of shipping full debug and non-debug versions of system libraries,
2175 system integrators can now instead ship just the stripped libraries
2176 and optional debug files.
2178 * DWARF 2 Location Expressions
2180 DWARF 2 Location Expressions allow the compiler to more completely
2181 describe the location of variables (even in optimized code) to the
2184 GDB now includes preliminary support for location expressions (support
2185 for DW_OP_piece is still missing).
2189 A number of long standing bugs that caused GDB to die while starting a
2190 Java application have been fixed. GDB's Java support is now
2191 considered "useable".
2193 * GNU/Linux support for fork, vfork, and exec.
2195 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2196 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2199 * GDB supports logging output to a file
2201 There are two new commands, "set logging" and "show logging", which can be
2202 used to capture GDB's output to a file.
2204 * The meaning of "detach" has changed for gdbserver
2206 The "detach" command will now resume the application, as documented. To
2207 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2210 * d10v, m68hc11 `regs' command deprecated
2212 The `info registers' command has been updated so that it displays the
2213 registers using a format identical to the old `regs' command.
2217 A new command, "maint set profile on/off", has been added. This command can
2218 be used to enable or disable profiling while running GDB, to profile a
2219 session or a set of commands. In addition there is a new configure switch,
2220 "--enable-profiling", which will cause GDB to be compiled with profiling
2221 data, for more informative profiling results.
2223 * Default MI syntax changed to "mi2".
2225 The default MI (machine interface) syntax, enabled by the command line
2226 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2227 "mi1", can be enabled by specifying the option "-i=mi1".
2229 Support for the original "mi0" syntax (included in GDB 5.0) has been
2232 Fix for gdb/192: removed extraneous space when displaying frame level.
2233 Fix for gdb/672: update changelist is now output in mi list format.
2234 Fix for gdb/702: a -var-assign that updates the value now shows up
2235 in a subsequent -var-update.
2237 * New native configurations.
2239 FreeBSD/amd64 x86_64-*-freebsd*
2241 * Multi-arched targets.
2243 HP/PA HPUX11 hppa*-*-hpux*
2244 Renesas M32R/D w/simulator m32r-*-elf*
2246 * OBSOLETE configurations and files
2248 Configurations that have been declared obsolete in this release have
2249 been commented out. Unless there is activity to revive these
2250 configurations, the next release of GDB will have their sources
2251 permanently REMOVED.
2253 Z8000 simulator z8k-zilog-none or z8ksim
2254 Matsushita MN10200 w/simulator mn10200-*-*
2255 H8/500 simulator h8500-hitachi-hms or h8500hms
2256 HP/PA running BSD hppa*-*-bsd*
2257 HP/PA running OSF/1 hppa*-*-osf*
2258 HP/PA Pro target hppa*-*-pro*
2259 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2260 Sequent family i[3456]86-sequent-sysv4*
2261 i[3456]86-sequent-sysv*
2262 i[3456]86-sequent-bsd*
2263 Tsqware Sparclet sparclet-*-*
2264 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2266 * REMOVED configurations and files
2269 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2270 IBM AIX PS/2 i[3456]86-*-aix
2271 i386 running Mach 3.0 i[3456]86-*-mach3*
2272 i386 running Mach i[3456]86-*-mach*
2273 i386 running OSF/1 i[3456]86-*osf1mk*
2274 HP/Apollo 68k Family m68*-apollo*-sysv*,
2276 m68*-hp-bsd*, m68*-hp-hpux*
2277 Argonaut Risc Chip (ARC) arc-*-*
2278 Mitsubishi D30V d30v-*-*
2279 Fujitsu FR30 fr30-*-elf*
2280 OS/9000 i[34]86-*-os9k
2281 I960 with MON960 i960-*-coff
2283 * MIPS $fp behavior changed
2285 The convenience variable $fp, for the MIPS, now consistently returns
2286 the address of the current frame's base. Previously, depending on the
2287 context, $fp could refer to either $sp or the current frame's base
2288 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2289 The GNU Source-Level Debugger''.
2291 *** Changes in GDB 5.3:
2293 * GNU/Linux shared library multi-threaded performance improved.
2295 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2296 `/proc', in preference to `ptrace' for memory reads. This may result
2297 in an improvement in the start-up time of multi-threaded, shared
2298 library applications when run under GDB. One GDB user writes: ``loads
2299 shared libs like mad''.
2301 * ``gdbserver'' now supports multi-threaded applications on some targets
2303 Support for debugging multi-threaded applications which use
2304 the GNU/Linux LinuxThreads package has been added for
2305 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2306 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2308 * GDB now supports C/C++ preprocessor macros.
2310 GDB now expands preprocessor macro invocations in C/C++ expressions,
2311 and provides various commands for showing macro definitions and how
2314 The new command `macro expand EXPRESSION' expands any macro
2315 invocations in expression, and shows the result.
2317 The new command `show macro MACRO-NAME' shows the definition of the
2318 macro named MACRO-NAME, and where it was defined.
2320 Most compilers don't include information about macros in the debugging
2321 information by default. In GCC 3.1, for example, you need to compile
2322 your program with the options `-gdwarf-2 -g3'. If the macro
2323 information is present in the executable, GDB will read it.
2325 * Multi-arched targets.
2327 DEC Alpha (partial) alpha*-*-*
2328 DEC VAX (partial) vax-*-*
2330 National Semiconductor NS32000 (partial) ns32k-*-*
2331 Motorola 68000 (partial) m68k-*-*
2332 Motorola MCORE mcore-*-*
2336 Fujitsu FRV architecture added by Red Hat frv*-*-*
2339 * New native configurations
2341 Alpha NetBSD alpha*-*-netbsd*
2342 SH NetBSD sh*-*-netbsdelf*
2343 MIPS NetBSD mips*-*-netbsd*
2344 UltraSPARC NetBSD sparc64-*-netbsd*
2346 * OBSOLETE configurations and files
2348 Configurations that have been declared obsolete in this release have
2349 been commented out. Unless there is activity to revive these
2350 configurations, the next release of GDB will have their sources
2351 permanently REMOVED.
2353 Mitsubishi D30V d30v-*-*
2354 OS/9000 i[34]86-*-os9k
2355 IBM AIX PS/2 i[3456]86-*-aix
2356 Fujitsu FR30 fr30-*-elf*
2357 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2358 Argonaut Risc Chip (ARC) arc-*-*
2359 i386 running Mach 3.0 i[3456]86-*-mach3*
2360 i386 running Mach i[3456]86-*-mach*
2361 i386 running OSF/1 i[3456]86-*osf1mk*
2362 HP/Apollo 68k Family m68*-apollo*-sysv*,
2364 m68*-hp-bsd*, m68*-hp-hpux*
2365 I960 with MON960 i960-*-coff
2367 * OBSOLETE languages
2369 CHILL, a Pascal like language used by telecommunications companies.
2371 * REMOVED configurations and files
2373 AMD 29k family via UDI a29k-amd-udi, udi29k
2374 A29K VxWorks a29k-*-vxworks
2375 AMD 29000 embedded, using EBMON a29k-none-none
2376 AMD 29000 embedded with COFF a29k-none-coff
2377 AMD 29000 embedded with a.out a29k-none-aout
2379 testsuite/gdb.hp/gdb.threads-hp/ directory
2381 * New command "set max-user-call-depth <nnn>"
2383 This command allows the user to limit the call depth of user-defined
2384 commands. The default is 1024.
2386 * Changes in FreeBSD/i386 native debugging.
2388 Support for the "generate-core-file" has been added.
2390 * New commands "dump", "append", and "restore".
2392 These commands allow data to be copied from target memory
2393 to a bfd-format or binary file (dump and append), and back
2394 from a file into memory (restore).
2396 * Improved "next/step" support on multi-processor Alpha Tru64.
2398 The previous single-step mechanism could cause unpredictable problems,
2399 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2400 of a software single-step mechanism prevents this.
2402 *** Changes in GDB 5.2.1:
2410 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2411 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2412 Fix, by Joel Brobecker imported from mainline.
2414 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2415 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2416 Fix, by Fred Fish, imported from mainline.
2418 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2419 Surprisingly enough, it works now.
2420 By Michal Ludvig, imported from mainline.
2422 i386 hardware watchpoint support:
2423 avoid misses on second run for some targets.
2424 By Pierre Muller, imported from mainline.
2426 *** Changes in GDB 5.2:
2428 * New command "set trust-readonly-sections on[off]".
2430 This command is a hint that tells gdb that read-only sections
2431 really are read-only (ie. that their contents will not change).
2432 In this mode, gdb will go to the object file rather than the
2433 target to read memory from read-only sections (such as ".text").
2434 This can be a significant performance improvement on some
2435 (notably embedded) targets.
2437 * New command "generate-core-file" (or "gcore").
2439 This new gdb command allows the user to drop a core file of the child
2440 process state at any time. So far it's been implemented only for
2441 GNU/Linux and Solaris, but should be relatively easily ported to other
2442 hosts. Argument is core file name (defaults to core.<pid>).
2444 * New command line option
2446 GDB now accepts --pid or -p followed by a process id.
2448 * Change in command line behavior -- corefiles vs. process ids.
2450 There is a subtle behavior in the way in which GDB handles
2451 command line arguments. The first non-flag argument is always
2452 a program to debug, but the second non-flag argument may either
2453 be a corefile or a process id. Previously, GDB would attempt to
2454 open the second argument as a corefile, and if that failed, would
2455 issue a superfluous error message and then attempt to attach it as
2456 a process. Now, if the second argument begins with a non-digit,
2457 it will be treated as a corefile. If it begins with a digit,
2458 GDB will attempt to attach it as a process, and if no such process
2459 is found, will then attempt to open it as a corefile.
2461 * Changes in ARM configurations.
2463 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2464 configuration is fully multi-arch.
2466 * New native configurations
2468 ARM NetBSD arm*-*-netbsd*
2469 x86 OpenBSD i[3456]86-*-openbsd*
2470 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2471 Sparc64 running FreeBSD sparc64-*-freebsd*
2475 Sanyo XStormy16 xstormy16-elf
2477 * OBSOLETE configurations and files
2479 Configurations that have been declared obsolete in this release have
2480 been commented out. Unless there is activity to revive these
2481 configurations, the next release of GDB will have their sources
2482 permanently REMOVED.
2484 AMD 29k family via UDI a29k-amd-udi, udi29k
2485 A29K VxWorks a29k-*-vxworks
2486 AMD 29000 embedded, using EBMON a29k-none-none
2487 AMD 29000 embedded with COFF a29k-none-coff
2488 AMD 29000 embedded with a.out a29k-none-aout
2490 testsuite/gdb.hp/gdb.threads-hp/ directory
2492 * REMOVED configurations and files
2494 TI TMS320C80 tic80-*-*
2496 PowerPC Solaris powerpcle-*-solaris*
2497 PowerPC Windows NT powerpcle-*-cygwin32
2498 PowerPC Netware powerpc-*-netware*
2499 Harris/CXUX m88k m88*-harris-cxux*
2500 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2501 ns32k-utek-sysv* ns32k-utek-*
2502 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2503 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2504 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2505 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2506 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2508 * Changes to command line processing
2510 The new `--args' feature can be used to specify command-line arguments
2511 for the inferior from gdb's command line.
2513 * Changes to key bindings
2515 There is a new `operate-and-get-next' function bound to `C-o'.
2517 *** Changes in GDB 5.1.1
2519 Fix compile problem on DJGPP.
2521 Fix a problem with floating-point registers on the i386 being
2524 Fix to stop GDB crashing on .debug_str debug info.
2526 Numerous documentation fixes.
2528 Numerous testsuite fixes.
2530 *** Changes in GDB 5.1:
2532 * New native configurations
2534 Alpha FreeBSD alpha*-*-freebsd*
2535 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2536 MIPS GNU/Linux mips*-*-linux*
2537 MIPS SGI Irix 6.x mips*-sgi-irix6*
2538 ia64 AIX ia64-*-aix*
2539 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2543 Motorola 68HC11 and 68HC12 m68hc11-elf
2545 UltraSparc running GNU/Linux sparc64-*-linux*
2547 * OBSOLETE configurations and files
2549 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2550 Harris/CXUX m88k m88*-harris-cxux*
2551 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2552 ns32k-utek-sysv* ns32k-utek-*
2553 TI TMS320C80 tic80-*-*
2555 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2556 PowerPC Solaris powerpcle-*-solaris*
2557 PowerPC Windows NT powerpcle-*-cygwin32
2558 PowerPC Netware powerpc-*-netware*
2559 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2560 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2561 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2562 Apple Macintosh (MPW) host N/A
2564 stuff.c (Program to stuff files into a specially prepared space in kdb)
2565 kdb-start.c (Main loop for the standalone kernel debugger)
2567 Configurations that have been declared obsolete in this release have
2568 been commented out. Unless there is activity to revive these
2569 configurations, the next release of GDB will have their sources
2570 permanently REMOVED.
2572 * REMOVED configurations and files
2574 Altos 3068 m68*-altos-*
2575 Convex c1-*-*, c2-*-*
2577 ARM RISCix arm-*-* (as host)
2581 * GDB has been converted to ISO C.
2583 GDB's source code has been converted to ISO C. In particular, the
2584 sources are fully protoized, and rely on standard headers being
2589 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2591 * The MI enabled by default.
2593 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2594 revised and enabled by default. Packages which use GDB as a debugging
2595 engine behind a UI or another front end are encouraged to switch to
2596 using the GDB/MI interface, instead of the old annotations interface
2597 which is now deprecated.
2599 * Support for debugging Pascal programs.
2601 GDB now includes support for debugging Pascal programs. The following
2602 main features are supported:
2604 - Pascal-specific data types such as sets;
2606 - automatic recognition of Pascal sources based on file-name
2609 - Pascal-style display of data types, variables, and functions;
2611 - a Pascal expression parser.
2613 However, some important features are not yet supported.
2615 - Pascal string operations are not supported at all;
2617 - there are some problems with boolean types;
2619 - Pascal type hexadecimal constants are not supported
2620 because they conflict with the internal variables format;
2622 - support for Pascal objects and classes is not full yet;
2624 - unlike Pascal, GDB is case-sensitive for symbol names.
2626 * Changes in completion.
2628 Commands such as `shell', `run' and `set args', which pass arguments
2629 to inferior programs, now complete on file names, similar to what
2630 users expect at the shell prompt.
2632 Commands which accept locations, such as `disassemble', `print',
2633 `breakpoint', `until', etc. now complete on filenames as well as
2634 program symbols. Thus, if you type "break foob TAB", and the source
2635 files linked into the programs include `foobar.c', that file name will
2636 be one of the candidates for completion. However, file names are not
2637 considered for completion after you typed a colon that delimits a file
2638 name from a name of a function in that file, as in "break foo.c:bar".
2640 `set demangle-style' completes on available demangling styles.
2642 * New platform-independent commands:
2644 It is now possible to define a post-hook for a command as well as a
2645 hook that runs before the command. For more details, see the
2646 documentation of `hookpost' in the GDB manual.
2648 * Changes in GNU/Linux native debugging.
2650 Support for debugging multi-threaded programs has been completely
2651 revised for all platforms except m68k and sparc. You can now debug as
2652 many threads as your system allows you to have.
2654 Attach/detach is supported for multi-threaded programs.
2656 Support for SSE registers was added for x86. This doesn't work for
2657 multi-threaded programs though.
2659 * Changes in MIPS configurations.
2661 Multi-arch support is enabled for all MIPS configurations.
2663 GDB can now be built as native debugger on SGI Irix 6.x systems for
2664 debugging n32 executables. (Debugging 64-bit executables is not yet
2667 * Unified support for hardware watchpoints in all x86 configurations.
2669 Most (if not all) native x86 configurations support hardware-assisted
2670 breakpoints and watchpoints in a unified manner. This support
2671 implements debug register sharing between watchpoints, which allows to
2672 put a virtually infinite number of watchpoints on the same address,
2673 and also supports watching regions up to 16 bytes with several debug
2676 The new maintenance command `maintenance show-debug-regs' toggles
2677 debugging print-outs in functions that insert, remove, and test
2678 watchpoints and hardware breakpoints.
2680 * Changes in the DJGPP native configuration.
2682 New command ``info dos sysinfo'' displays assorted information about
2683 the CPU, OS, memory, and DPMI server.
2685 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2686 display information about segment descriptors stored in GDT, LDT, and
2689 New commands ``info dos pde'' and ``info dos pte'' display entries
2690 from Page Directory and Page Tables (for now works with CWSDPMI only).
2691 New command ``info dos address-pte'' displays the Page Table entry for
2692 a given linear address.
2694 GDB can now pass command lines longer than 126 characters to the
2695 program being debugged (requires an update to the libdbg.a library
2696 which is part of the DJGPP development kit).
2698 DWARF2 debug info is now supported.
2700 It is now possible to `step' and `next' through calls to `longjmp'.
2702 * Changes in documentation.
2704 All GDB documentation was converted to GFDL, the GNU Free
2705 Documentation License.
2707 Tracepoints-related commands are now fully documented in the GDB
2710 TUI, the Text-mode User Interface, is now documented in the manual.
2712 Tracepoints-related commands are now fully documented in the GDB
2715 The "GDB Internals" manual now has an index. It also includes
2716 documentation of `ui_out' functions, GDB coding standards, x86
2717 hardware watchpoints, and memory region attributes.
2719 * GDB's version number moved to ``version.in''
2721 The Makefile variable VERSION has been replaced by the file
2722 ``version.in''. People creating GDB distributions should update the
2723 contents of this file.
2727 GUD support is now a standard part of the EMACS distribution.
2729 *** Changes in GDB 5.0:
2731 * Improved support for debugging FP programs on x86 targets
2733 Unified and much-improved support for debugging floating-point
2734 programs on all x86 targets. In particular, ``info float'' now
2735 displays the FP registers in the same format on all x86 targets, with
2736 greater level of detail.
2738 * Improvements and bugfixes in hardware-assisted watchpoints
2740 It is now possible to watch array elements, struct members, and
2741 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2742 on x86 targets no longer erroneously trigger when the address is
2745 * Improvements in the native DJGPP version of GDB
2747 The distribution now includes all the scripts and auxiliary files
2748 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2749 machines ``out of the box''.
2751 The DJGPP version can now debug programs that use signals. It is
2752 possible to catch signals that happened in the debuggee, deliver
2753 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2754 would kill the program being debugged.) Programs that hook hardware
2755 interrupts (keyboard, timer, etc.) can also be debugged.
2757 It is now possible to debug DJGPP programs that redirect their
2758 standard handles or switch them to raw (as opposed to cooked) mode, or
2759 even close them. The command ``run < foo > bar'' works as expected,
2760 and ``info terminal'' reports useful information about the debuggee's
2761 terminal, including raw/cooked mode, redirection, etc.
2763 The DJGPP version now uses termios functions for console I/O, which
2764 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2767 DOS-style file names with drive letters are now fully supported by
2770 It is now possible to debug DJGPP programs that switch their working
2771 directory. It is also possible to rerun the debuggee any number of
2772 times without restarting GDB; thus, you can use the same setup,
2773 breakpoints, etc. for many debugging sessions.
2775 * New native configurations
2777 ARM GNU/Linux arm*-*-linux*
2778 PowerPC GNU/Linux powerpc-*-linux*
2782 Motorola MCore mcore-*-*
2783 x86 VxWorks i[3456]86-*-vxworks*
2784 PowerPC VxWorks powerpc-*-vxworks*
2785 TI TMS320C80 tic80-*-*
2787 * OBSOLETE configurations
2789 Altos 3068 m68*-altos-*
2790 Convex c1-*-*, c2-*-*
2792 ARM RISCix arm-*-* (as host)
2795 Configurations that have been declared obsolete will be commented out,
2796 but the code will be left in place. If there is no activity to revive
2797 these configurations before the next release of GDB, the sources will
2798 be permanently REMOVED.
2800 * Gould support removed
2802 Support for the Gould PowerNode and NP1 has been removed.
2804 * New features for SVR4
2806 On SVR4 native platforms (such as Solaris), if you attach to a process
2807 without first loading a symbol file, GDB will now attempt to locate and
2808 load symbols from the running process's executable file.
2810 * Many C++ enhancements
2812 C++ support has been greatly improved. Overload resolution now works properly
2813 in almost all cases. RTTI support is on the way.
2815 * Remote targets can connect to a sub-program
2817 A popen(3) style serial-device has been added. This device starts a
2818 sub-process (such as a stand-alone simulator) and then communicates
2819 with that. The sub-program to run is specified using the syntax
2820 ``|<program> <args>'' vis:
2822 (gdb) set remotedebug 1
2823 (gdb) target extended-remote |mn10300-elf-sim program-args
2825 * MIPS 64 remote protocol
2827 A long standing bug in the mips64 remote protocol where by GDB
2828 expected certain 32 bit registers (ex SR) to be transfered as 32
2829 instead of 64 bits has been fixed.
2831 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2832 added to provide backward compatibility with older versions of GDB.
2834 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2836 The command ``set remotebinarydownload'' command has been replaced by
2837 ``set remote X-packet''. Other commands in ``set remote'' family
2838 include ``set remote P-packet''.
2840 * Breakpoint commands accept ranges.
2842 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2843 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2844 ``tracepoint passcount'' also accepts a range of tracepoints.
2846 * ``apropos'' command added.
2848 The ``apropos'' command searches through command names and
2849 documentation strings, printing out matches, making it much easier to
2850 try to find a command that does what you are looking for.
2854 A new machine oriented interface (MI) has been added to GDB. This
2855 interface is designed for debug environments running GDB as a separate
2856 process. This is part of the long term libGDB project. See the
2857 "GDB/MI" chapter of the GDB manual for further information. It can be
2858 enabled by configuring with:
2860 .../configure --enable-gdbmi
2862 *** Changes in GDB-4.18:
2864 * New native configurations
2866 HP-UX 10.20 hppa*-*-hpux10.20
2867 HP-UX 11.x hppa*-*-hpux11.0*
2868 M68K GNU/Linux m68*-*-linux*
2872 Fujitsu FR30 fr30-*-elf*
2873 Intel StrongARM strongarm-*-*
2874 Mitsubishi D30V d30v-*-*
2876 * OBSOLETE configurations
2878 Gould PowerNode, NP1 np1-*-*, pn-*-*
2880 Configurations that have been declared obsolete will be commented out,
2881 but the code will be left in place. If there is no activity to revive
2882 these configurations before the next release of GDB, the sources will
2883 be permanently REMOVED.
2887 As a compatibility experiment, GDB's source files buildsym.h and
2888 buildsym.c have been converted to pure standard C, no longer
2889 containing any K&R compatibility code. We believe that all systems in
2890 use today either come with a standard C compiler, or have a GCC port
2891 available. If this is not true, please report the affected
2892 configuration to bug-gdb@gnu.org immediately. See the README file for
2893 information about getting a standard C compiler if you don't have one
2898 GDB now uses readline 2.2.
2900 * set extension-language
2902 You can now control the mapping between filename extensions and source
2903 languages by using the `set extension-language' command. For instance,
2904 you can ask GDB to treat .c files as C++ by saying
2905 set extension-language .c c++
2906 The command `info extensions' lists all of the recognized extensions
2907 and their associated languages.
2909 * Setting processor type for PowerPC and RS/6000
2911 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2912 you can use the `set processor' command to specify what variant of the
2913 PowerPC family you are debugging. The command
2917 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2918 following PowerPC and RS6000 variants:
2920 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2921 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2923 403GC IBM PowerPC 403GC
2924 505 Motorola PowerPC 505
2925 860 Motorola PowerPC 860 or 850
2926 601 Motorola PowerPC 601
2927 602 Motorola PowerPC 602
2928 603 Motorola/IBM PowerPC 603 or 603e
2929 604 Motorola PowerPC 604 or 604e
2930 750 Motorola/IBM PowerPC 750 or 750
2932 At the moment, this command just tells GDB what to name the
2933 special-purpose processor registers. Since almost all the affected
2934 registers are inaccessible to user-level programs, this command is
2935 only useful for remote debugging in its present form.
2939 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2940 more extensive support for HP-UX. Added features include shared
2941 library support, kernel threads and hardware watchpoints for 11.00,
2942 support for HP's ANSI C and C++ compilers, and a compatibility mode
2943 for xdb and dbx commands.
2947 HP's donation includes the new concept of catchpoints, which is a
2948 generalization of the old catch command. On HP-UX, it is now possible
2949 to catch exec, fork, and vfork, as well as library loading.
2951 This means that the existing catch command has changed; its first
2952 argument now specifies the type of catch to be set up. See the
2953 output of "help catch" for a list of catchpoint types.
2955 * Debugging across forks
2957 On HP-UX, you can choose which process to debug when a fork() happens
2962 HP has donated a curses-based terminal user interface (TUI). To get
2963 it, build with --enable-tui. Although this can be enabled for any
2964 configuration, at present it only works for native HP debugging.
2966 * GDB remote protocol additions
2968 A new protocol packet 'X' that writes binary data is now available.
2969 Default behavior is to try 'X', then drop back to 'M' if the stub
2970 fails to respond. The settable variable `remotebinarydownload'
2971 allows explicit control over the use of 'X'.
2973 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2974 full 64-bit address. The command
2976 set remoteaddresssize 32
2978 can be used to revert to the old behaviour. For existing remote stubs
2979 the change should not be noticed, as the additional address information
2982 In order to assist in debugging stubs, you may use the maintenance
2983 command `packet' to send any text string to the stub. For instance,
2985 maint packet heythere
2987 sends the packet "$heythere#<checksum>". Note that it is very easy to
2988 disrupt a debugging session by sending the wrong packet at the wrong
2991 The compare-sections command allows you to compare section data on the
2992 target to what is in the executable file without uploading or
2993 downloading, by comparing CRC checksums.
2995 * Tracing can collect general expressions
2997 You may now collect general expressions at tracepoints. This requires
2998 further additions to the target-side stub; see tracepoint.c and
2999 doc/agentexpr.texi for further details.
3001 * mask-address variable for Mips
3003 For Mips targets, you may control the zeroing of the upper 32 bits of
3004 a 64-bit address by entering `set mask-address on'. This is mainly
3005 of interest to users of embedded R4xxx and R5xxx processors.
3007 * Higher serial baud rates
3009 GDB's serial code now allows you to specify baud rates 57600, 115200,
3010 230400, and 460800 baud. (Note that your host system may not be able
3011 to achieve all of these rates.)
3015 The i960 configuration now includes an initial implementation of a
3016 builtin simulator, contributed by Jim Wilson.
3019 *** Changes in GDB-4.17:
3021 * New native configurations
3023 Alpha GNU/Linux alpha*-*-linux*
3024 Unixware 2.x i[3456]86-unixware2*
3025 Irix 6.x mips*-sgi-irix6*
3026 PowerPC GNU/Linux powerpc-*-linux*
3027 PowerPC Solaris powerpcle-*-solaris*
3028 Sparc GNU/Linux sparc-*-linux*
3029 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3033 Argonaut Risc Chip (ARC) arc-*-*
3034 Hitachi H8/300S h8300*-*-*
3035 Matsushita MN10200 w/simulator mn10200-*-*
3036 Matsushita MN10300 w/simulator mn10300-*-*
3037 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3038 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3039 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3040 Mitsubishi D10V w/simulator d10v-*-*
3041 Mitsubishi M32R/D w/simulator m32r-*-elf*
3042 Tsqware Sparclet sparclet-*-*
3043 NEC V850 w/simulator v850-*-*
3045 * New debugging protocols
3047 ARM with RDI protocol arm*-*-*
3048 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3049 DDB and LSI variants of PMON protocol mips*-*-*
3050 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3051 PowerPC with SDS protocol powerpc{,le}-*-eabi
3052 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3056 All configurations can now understand and use the DWARF 2 debugging
3057 format. The choice is automatic, if the symbol file contains DWARF 2
3062 GDB now includes basic Java language support. This support is
3063 only useful with Java compilers that produce native machine code.
3065 * solib-absolute-prefix and solib-search-path
3067 For SunOS and SVR4 shared libraries, you may now set the prefix for
3068 loading absolute shared library symbol files, and the search path for
3069 locating non-absolute shared library symbol files.
3071 * Live range splitting
3073 GDB can now effectively debug code for which GCC has performed live
3074 range splitting as part of its optimization. See gdb/doc/LRS for
3075 more details on the expected format of the stabs information.
3079 GDB's support for the GNU Hurd, including thread debugging, has been
3080 updated to work with current versions of the Hurd.
3084 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3085 instruction set. ARM GDB automatically detects when Thumb
3086 instructions are in use, and adjusts disassembly and backtracing
3091 GDB's MIPS target configurations now handle the MIP16 16-bit
3096 GDB now includes support for overlays; if an executable has been
3097 linked such that multiple sections are based at the same address, GDB
3098 will decide which section to use for symbolic info. You can choose to
3099 control the decision manually, using overlay commands, or implement
3100 additional target-side support and use "overlay load-target" to bring
3101 in the overlay mapping. Do "help overlay" for more detail.
3105 The command "info symbol <address>" displays information about
3106 the symbol at the specified address.
3110 The standard remote protocol now includes an extension that allows
3111 asynchronous collection and display of trace data. This requires
3112 extensive support in the target-side debugging stub. Tracing mode
3113 includes a new interaction mode in GDB and new commands: see the
3114 file tracepoint.c for more details.
3118 Configurations for embedded MIPS now include a simulator contributed
3119 by Cygnus Solutions. The simulator supports the instruction sets
3120 of most MIPS variants.
3124 Sparc configurations may now include the ERC32 simulator contributed
3125 by the European Space Agency. The simulator is not built into
3126 Sparc targets by default; configure with --enable-sim to include it.
3130 For target configurations that may include multiple variants of a
3131 basic architecture (such as MIPS and SH), you may now set the
3132 architecture explicitly. "set arch" sets, "info arch" lists
3133 the possible architectures.
3135 *** Changes in GDB-4.16:
3137 * New native configurations
3139 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3140 M68K NetBSD m68k-*-netbsd*
3141 PowerPC AIX 4.x powerpc-*-aix*
3142 PowerPC MacOS powerpc-*-macos*
3143 PowerPC Windows NT powerpcle-*-cygwin32
3144 RS/6000 AIX 4.x rs6000-*-aix4*
3148 ARM with RDP protocol arm-*-*
3149 I960 with MON960 i960-*-coff
3150 MIPS VxWorks mips*-*-vxworks*
3151 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3152 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3154 Matra Sparclet sparclet-*-*
3158 The powerpc-eabi configuration now includes the PSIM simulator,
3159 contributed by Andrew Cagney, with assistance from Mike Meissner.
3160 PSIM is a very elaborate model of the PowerPC, including not only
3161 basic instruction set execution, but also details of execution unit
3162 performance and I/O hardware. See sim/ppc/README for more details.
3166 GDB now works with Solaris 2.5.
3168 * Windows 95/NT native
3170 GDB will now work as a native debugger on Windows 95 and Windows NT.
3171 To build it from source, you must use the "gnu-win32" environment,
3172 which uses a DLL to emulate enough of Unix to run the GNU tools.
3173 Further information, binaries, and sources are available at
3174 ftp.cygnus.com, under pub/gnu-win32.
3176 * dont-repeat command
3178 If a user-defined command includes the command `dont-repeat', then the
3179 command will not be repeated if the user just types return. This is
3180 useful if the command is time-consuming to run, so that accidental
3181 extra keystrokes don't run the same command many times.
3183 * Send break instead of ^C
3185 The standard remote protocol now includes an option to send a break
3186 rather than a ^C to the target in order to interrupt it. By default,
3187 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3189 * Remote protocol timeout
3191 The standard remote protocol includes a new variable `remotetimeout'
3192 that allows you to set the number of seconds before GDB gives up trying
3193 to read from the target. The default value is 2.
3195 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3197 By default GDB will automatically keep track of objects as they are
3198 loaded and unloaded by the dynamic linker. By using the command `set
3199 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3200 when shared library events occur, thus allowing you to set breakpoints
3201 in shared libraries which are explicitly loaded by the inferior.
3203 Note this feature does not work on hpux8. On hpux9 you must link
3204 /usr/lib/end.o into your program. This feature should work
3205 automatically on hpux10.
3207 * Irix 5.x hardware watchpoint support
3209 Irix 5 configurations now support the use of hardware watchpoints.
3211 * Mips protocol "SYN garbage limit"
3213 When debugging a Mips target using the `target mips' protocol, you
3214 may set the number of characters that GDB will ignore by setting
3215 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3216 every character. The default value is 1050.
3218 * Recording and replaying remote debug sessions
3220 If you set `remotelogfile' to the name of a file, gdb will write to it
3221 a recording of a remote debug session. This recording may then be
3222 replayed back to gdb using "gdbreplay". See gdbserver/README for
3223 details. This is useful when you have a problem with GDB while doing
3224 remote debugging; you can make a recording of the session and send it
3225 to someone else, who can then recreate the problem.
3227 * Speedups for remote debugging
3229 GDB includes speedups for downloading and stepping MIPS systems using
3230 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3231 and more efficient S-record downloading.
3233 * Memory use reductions and statistics collection
3235 GDB now uses less memory and reports statistics about memory usage.
3236 Try the `maint print statistics' command, for example.
3238 *** Changes in GDB-4.15:
3240 * Psymtabs for XCOFF
3242 The symbol reader for AIX GDB now uses partial symbol tables. This
3243 can greatly improve startup time, especially for large executables.
3245 * Remote targets use caching
3247 Remote targets now use a data cache to speed up communication with the
3248 remote side. The data cache could lead to incorrect results because
3249 it doesn't know about volatile variables, thus making it impossible to
3250 debug targets which use memory mapped I/O devices. `set remotecache
3251 off' turns the the data cache off.
3253 * Remote targets may have threads
3255 The standard remote protocol now includes support for multiple threads
3256 in the target system, using new protocol commands 'H' and 'T'. See
3257 gdb/remote.c for details.
3261 If GDB is configured with `--enable-netrom', then it will include
3262 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3263 acts as though it is a bank of ROM on the target board, but you can
3264 write into it over the network. GDB's support consists only of
3265 support for fast loading into the emulated ROM; to debug, you must use
3266 another protocol, such as standard remote protocol. The usual
3267 sequence is something like
3269 target nrom <netrom-hostname>
3271 target remote <netrom-hostname>:1235
3275 GDB now includes support for the Apple Macintosh, as a host only. It
3276 may be run as either an MPW tool or as a standalone application, and
3277 it can debug through the serial port. All the usual GDB commands are
3278 available, but to the target command, you must supply "serial" as the
3279 device type instead of "/dev/ttyXX". See mpw-README in the main
3280 directory for more information on how to build. The MPW configuration
3281 scripts */mpw-config.in support only a few targets, and only the
3282 mips-idt-ecoff target has been tested.
3286 GDB configuration now uses autoconf. This is not user-visible,
3287 but does simplify configuration and building.
3291 GDB now supports hpux10.
3293 *** Changes in GDB-4.14:
3295 * New native configurations
3297 x86 FreeBSD i[345]86-*-freebsd
3298 x86 NetBSD i[345]86-*-netbsd
3299 NS32k NetBSD ns32k-*-netbsd
3300 Sparc NetBSD sparc-*-netbsd
3304 A29K VxWorks a29k-*-vxworks
3305 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3306 CPU32 EST-300 emulator m68*-*-est*
3307 PowerPC ELF powerpc-*-elf
3310 * Alpha OSF/1 support for procfs
3312 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3313 possible to attach to running processes. As the mounting of the /proc
3314 filesystem is optional on the Alpha, GDB automatically determines
3315 the availability of /proc during startup. This can lead to problems
3316 if /proc is unmounted after GDB has been started.
3318 * Arguments to user-defined commands
3320 User commands may accept up to 10 arguments separated by whitespace.
3321 Arguments are accessed within the user command via $arg0..$arg9. A
3324 print $arg0 + $arg1 + $arg2
3326 To execute the command use:
3329 Defines the command "adder" which prints the sum of its three arguments.
3330 Note the arguments are text substitutions, so they may reference variables,
3331 use complex expressions, or even perform inferior function calls.
3333 * New `if' and `while' commands
3335 This makes it possible to write more sophisticated user-defined
3336 commands. Both commands take a single argument, which is the
3337 expression to evaluate, and must be followed by the commands to
3338 execute, one per line, if the expression is nonzero, the list being
3339 terminated by the word `end'. The `if' command list may include an
3340 `else' word, which causes the following commands to be executed only
3341 if the expression is zero.
3343 * Fortran source language mode
3345 GDB now includes partial support for Fortran 77. It will recognize
3346 Fortran programs and can evaluate a subset of Fortran expressions, but
3347 variables and functions may not be handled correctly. GDB will work
3348 with G77, but does not yet know much about symbols emitted by other
3351 * Better HPUX support
3353 Most debugging facilities now work on dynamic executables for HPPAs
3354 running hpux9 or later. You can attach to running dynamically linked
3355 processes, but by default the dynamic libraries will be read-only, so
3356 for instance you won't be able to put breakpoints in them. To change
3357 that behavior do the following before running the program:
3363 This will cause the libraries to be mapped private and read-write.
3364 To revert to the normal behavior, do this:
3370 You cannot set breakpoints or examine data in the library until after
3371 the library is loaded if the function/data symbols do not have
3374 GDB can now also read debug symbols produced by the HP C compiler on
3375 HPPAs (sorry, no C++, Fortran or 68k support).
3377 * Target byte order now dynamically selectable
3379 You can choose which byte order to use with a target system, via the
3380 commands "set endian big" and "set endian little", and you can see the
3381 current setting by using "show endian". You can also give the command
3382 "set endian auto", in which case GDB will use the byte order
3383 associated with the executable. Currently, only embedded MIPS
3384 configurations support dynamic selection of target byte order.
3386 * New DOS host serial code
3388 This version uses DPMI interrupts to handle buffered I/O, so you
3389 no longer need to run asynctsr when debugging boards connected to
3392 *** Changes in GDB-4.13:
3394 * New "complete" command
3396 This lists all the possible completions for the rest of the line, if it
3397 were to be given as a command itself. This is intended for use by emacs.
3399 * Trailing space optional in prompt
3401 "set prompt" no longer adds a space for you after the prompt you set. This
3402 allows you to set a prompt which ends in a space or one that does not.
3404 * Breakpoint hit counts
3406 "info break" now displays a count of the number of times the breakpoint
3407 has been hit. This is especially useful in conjunction with "ignore"; you
3408 can ignore a large number of breakpoint hits, look at the breakpoint info
3409 to see how many times the breakpoint was hit, then run again, ignoring one
3410 less than that number, and this will get you quickly to the last hit of
3413 * Ability to stop printing at NULL character
3415 "set print null-stop" will cause GDB to stop printing the characters of
3416 an array when the first NULL is encountered. This is useful when large
3417 arrays actually contain only short strings.
3419 * Shared library breakpoints
3421 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3422 breakpoints in shared libraries before the executable is run.
3424 * Hardware watchpoints
3426 There is a new hardware breakpoint for the watch command for sparclite
3427 targets. See gdb/sparclite/hw_breakpoint.note.
3429 Hardware watchpoints are also now supported under GNU/Linux.
3433 Annotations have been added. These are for use with graphical interfaces,
3434 and are still experimental. Currently only gdba.el uses these.
3436 * Improved Irix 5 support
3438 GDB now works properly with Irix 5.2.
3440 * Improved HPPA support
3442 GDB now works properly with the latest GCC and GAS.
3444 * New native configurations
3446 Sequent PTX4 i[34]86-sequent-ptx4
3447 HPPA running OSF/1 hppa*-*-osf*
3448 Atari TT running SVR4 m68*-*-sysv4*
3449 RS/6000 LynxOS rs6000-*-lynxos*
3453 OS/9000 i[34]86-*-os9k
3454 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3457 * Hitachi SH7000 and E7000-PC ICE support
3459 There is now support for communicating with the Hitachi E7000-PC ICE.
3460 This is available automatically when GDB is configured for the SH.
3464 As usual, a variety of small fixes and improvements, both generic
3465 and configuration-specific. See the ChangeLog for more detail.
3467 *** Changes in GDB-4.12:
3469 * Irix 5 is now supported
3473 GDB-4.12 on the HPPA has a number of changes which make it unable
3474 to debug the output from the currently released versions of GCC and
3475 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3476 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3477 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3480 *** Changes in GDB-4.11:
3482 * User visible changes:
3486 The "set remotedebug" option is now consistent between the mips remote
3487 target, remote targets using the gdb-specific protocol, UDI (AMD's
3488 debug protocol for the 29k) and the 88k bug monitor. It is now an
3489 integer specifying a debug level (normally 0 or 1, but 2 means more
3490 debugging info for the mips target).
3492 * DEC Alpha native support
3494 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3495 debug info, but GDB works fairly well with the DEC compiler and should
3496 work with a future GCC release. See the README file for a few
3497 Alpha-specific notes.
3499 * Preliminary thread implementation
3501 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3503 * LynxOS native and target support for 386
3505 This release has been hosted on LynxOS 2.2, and also can be configured
3506 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3509 * Improvements in C++ mangling/demangling.
3511 This release has much better g++ debugging, specifically in name
3512 mangling/demangling, virtual function calls, print virtual table,
3513 call methods, ...etc.
3515 *** Changes in GDB-4.10:
3517 * User visible changes:
3519 Remote debugging using the GDB-specific (`target remote') protocol now
3520 supports the `load' command. This is only useful if you have some
3521 other way of getting the stub to the target system, and you can put it
3522 somewhere in memory where it won't get clobbered by the download.
3524 Filename completion now works.
3526 When run under emacs mode, the "info line" command now causes the
3527 arrow to point to the line specified. Also, "info line" prints
3528 addresses in symbolic form (as well as hex).
3530 All vxworks based targets now support a user settable option, called
3531 vxworks-timeout. This option represents the number of seconds gdb
3532 should wait for responses to rpc's. You might want to use this if
3533 your vxworks target is, perhaps, a slow software simulator or happens
3534 to be on the far side of a thin network line.
3538 This release contains support for using a DEC alpha as a GDB host for
3539 cross debugging. Native alpha debugging is not supported yet.
3542 *** Changes in GDB-4.9:
3546 This is the first GDB release which is accompanied by a matching testsuite.
3547 The testsuite requires installation of dejagnu, which should be available
3548 via ftp from most sites that carry GNU software.
3552 'Cfront' style demangling has had its name changed to 'ARM' style, to
3553 emphasize that it was written from the specifications in the C++ Annotated
3554 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3555 disclaimers, it still generated too much confusion with users attempting to
3556 use gdb with AT&T cfront.
3560 GDB now uses a standard remote interface to a simulator library.
3561 So far, the library contains simulators for the Zilog Z8001/2, the
3562 Hitachi H8/300, H8/500 and Super-H.
3564 * New targets supported
3566 H8/300 simulator h8300-hitachi-hms or h8300hms
3567 H8/500 simulator h8500-hitachi-hms or h8500hms
3568 SH simulator sh-hitachi-hms or sh
3569 Z8000 simulator z8k-zilog-none or z8ksim
3570 IDT MIPS board over serial line mips-idt-ecoff
3572 Cross-debugging to GO32 targets is supported. It requires a custom
3573 version of the i386-stub.c module which is integrated with the
3574 GO32 memory extender.
3576 * New remote protocols
3578 MIPS remote debugging protocol.
3580 * New source languages supported
3582 This version includes preliminary support for Chill, a Pascal like language
3583 used by telecommunications companies. Chill support is also being integrated
3584 into the GNU compiler, but we don't know when it will be publically available.
3587 *** Changes in GDB-4.8:
3589 * HP Precision Architecture supported
3591 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3592 version of this support was available as a set of patches from the
3593 University of Utah. GDB does not support debugging of programs
3594 compiled with the HP compiler, because HP will not document their file
3595 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3596 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3598 Many problems in the preliminary version have been fixed.
3600 * Faster and better demangling
3602 We have improved template demangling and fixed numerous bugs in the GNU style
3603 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3604 character types (wchar_t) are now supported. Demangling of each symbol is now
3605 only done once, and is cached when the symbol table for a file is read in.
3606 This results in a small increase in memory usage for C programs, a moderate
3607 increase in memory usage for C++ programs, and a fantastic speedup in
3610 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3611 from the specifications in the Annotated Reference Manual, which AT&T's
3612 compiler does not actually implement.
3614 * G++ multiple inheritance compiler problem
3616 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3617 inheritance lattices was reworked to properly discover ambiguities. We
3618 recently found an example which causes this new algorithm to fail in a
3619 very subtle way, producing bad debug information for those classes.
3620 The file 'gcc.patch' (in this directory) can be applied to gcc to
3621 circumvent the problem. A future GCC release will contain a complete
3624 The previous G++ debug info problem (mentioned below for the gdb-4.7
3625 release) is fixed in gcc version 2.3.2.
3627 * Improved configure script
3629 The `configure' script will now attempt to guess your system type if
3630 you don't supply a host system type. The old scheme of supplying a
3631 host system triplet is preferable over using this. All the magic is
3632 done in the new `config.guess' script. Examine it for details.
3634 We have also brought our configure script much more in line with the FSF's
3635 version. It now supports the --with-xxx options. In particular,
3636 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3637 The resulting GDB will not be able to read arbitrary object file formats --
3638 only the format ``expected'' to be used on the configured target system.
3639 We hope to make this the default in a future release.
3641 * Documentation improvements
3643 There's new internal documentation on how to modify GDB, and how to
3644 produce clean changes to the code. We implore people to read it
3645 before submitting changes.
3647 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3648 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3649 `info' files are also provided. To build `info' files from scratch,
3650 you will need the latest `makeinfo' release, which will be available in
3651 a future texinfo-X.Y release.
3653 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3654 We're not sure exactly which versions have this problem, but it has
3655 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3656 or better. If that isn't possible, there is a patch in
3657 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3658 around this problem.
3662 GDB now supports array constants that can be used in expressions typed in by
3663 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3664 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3667 The new directory `gdb/sparclite' contains a program that demonstrates
3668 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3670 * New native hosts supported
3672 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3673 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3675 * New targets supported
3677 AMD 29k family via UDI a29k-amd-udi or udi29k
3679 * New file formats supported
3681 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3682 HPUX core files, and SCO 3.2v2 core files.
3686 Attaching to processes now works again; thanks for the many bug reports.
3688 We have also stomped on a bunch of core dumps caused by
3689 printf_filtered("%s") problems.
3691 We eliminated a copyright problem on the rpc and ptrace header files
3692 for VxWorks, which was discovered at the last minute during the 4.7
3693 release. You should now be able to build a VxWorks GDB.
3695 You can now interrupt gdb while an attached process is running. This
3696 will cause the attached process to stop, and give control back to GDB.
3698 We fixed problems caused by using too many file descriptors
3699 for reading symbols from object files and libraries. This was
3700 especially a problem for programs that used many (~100) shared
3703 The `step' command now only enters a subroutine if there is line number
3704 information for the subroutine. Otherwise it acts like the `next'
3705 command. Previously, `step' would enter subroutines if there was
3706 any debugging information about the routine. This avoids problems
3707 when using `cc -g1' on MIPS machines.
3709 * Internal improvements
3711 GDB's internal interfaces have been improved to make it easier to support
3712 debugging of multiple languages in the future.
3714 GDB now uses a common structure for symbol information internally.
3715 Minimal symbols (derived from linkage symbols in object files), partial
3716 symbols (from a quick scan of debug information), and full symbols
3717 contain a common subset of information, making it easier to write
3718 shared code that handles any of them.
3720 * New command line options
3722 We now accept --silent as an alias for --quiet.
3726 The memory-mapped-malloc library is now licensed under the GNU Library
3727 General Public License.
3729 *** Changes in GDB-4.7:
3731 * Host/native/target split
3733 GDB has had some major internal surgery to untangle the support for
3734 hosts and remote targets. Now, when you configure GDB for a remote
3735 target, it will no longer load in all of the support for debugging
3736 local programs on the host. When fully completed and tested, this will
3737 ensure that arbitrary host/target combinations are possible.
3739 The primary conceptual shift is to separate the non-portable code in
3740 GDB into three categories. Host specific code is required any time GDB
3741 is compiled on that host, regardless of the target. Target specific
3742 code relates to the peculiarities of the target, but can be compiled on
3743 any host. Native specific code is everything else: it can only be
3744 built when the host and target are the same system. Child process
3745 handling and core file support are two common `native' examples.
3747 GDB's use of /proc for controlling Unix child processes is now cleaner.
3748 It has been split out into a single module under the `target_ops' vector,
3749 plus two native-dependent functions for each system that uses /proc.
3751 * New hosts supported
3753 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3754 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3755 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3757 * New targets supported
3759 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3760 68030 and CPU32 m68030-*-*, m68332-*-*
3762 * New native hosts supported
3764 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3765 (386bsd is not well tested yet)
3766 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3768 * New file formats supported
3770 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3771 supports reading of `a.out.adobe' object files, which are an a.out
3772 format extended with minimal information about multiple sections.
3776 `show copying' is the same as the old `info copying'.
3777 `show warranty' is the same as `info warrantee'.
3778 These were renamed for consistency. The old commands continue to work.
3780 `info handle' is a new alias for `info signals'.
3782 You can now define pre-command hooks, which attach arbitrary command
3783 scripts to any command. The commands in the hook will be executed
3784 prior to the user's command. You can also create a hook which will be
3785 executed whenever the program stops. See gdb.texinfo.
3789 We now deal with Cfront style name mangling, and can even extract type
3790 info from mangled symbols. GDB can automatically figure out which
3791 symbol mangling style your C++ compiler uses.
3793 Calling of methods and virtual functions has been improved as well.
3797 The crash that occured when debugging Sun Ansi-C compiled binaries is
3798 fixed. This was due to mishandling of the extra N_SO stabs output
3801 We also finally got Ultrix 4.2 running in house, and fixed core file
3802 support, with help from a dozen people on the net.
3804 John M. Farrell discovered that the reason that single-stepping was so
3805 slow on all of the Mips based platforms (primarily SGI and DEC) was
3806 that we were trying to demangle and lookup a symbol used for internal
3807 purposes on every instruction that was being stepped through. Changing
3808 the name of that symbol so that it couldn't be mistaken for a C++
3809 mangled symbol sped things up a great deal.
3811 Rich Pixley sped up symbol lookups in general by getting much smarter
3812 about when C++ symbol mangling is necessary. This should make symbol
3813 completion (TAB on the command line) much faster. It's not as fast as
3814 we'd like, but it's significantly faster than gdb-4.6.
3818 A new user controllable variable 'call_scratch_address' can
3819 specify the location of a scratch area to be used when GDB
3820 calls a function in the target. This is necessary because the
3821 usual method of putting the scratch area on the stack does not work
3822 in systems that have separate instruction and data spaces.
3824 We integrated changes to support the 29k UDI (Universal Debugger
3825 Interface), but discovered at the last minute that we didn't have all
3826 of the appropriate copyright paperwork. We are working with AMD to
3827 resolve this, and hope to have it available soon.
3831 We have sped up the remote serial line protocol, especially for targets
3832 with lots of registers. It now supports a new `expedited status' ('T')
3833 message which can be used in place of the existing 'S' status message.
3834 This allows the remote stub to send only the registers that GDB
3835 needs to make a quick decision about single-stepping or conditional
3836 breakpoints, eliminating the need to fetch the entire register set for
3837 each instruction being stepped through.
3839 The GDB remote serial protocol now implements a write-through cache for
3840 registers, only re-reading the registers if the target has run.
3842 There is also a new remote serial stub for SPARC processors. You can
3843 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3844 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3845 processor with a serial port.
3849 Configure.in files have become much easier to read and modify. A new
3850 `table driven' format makes it more obvious what configurations are
3851 supported, and what files each one uses.
3855 There is a new opcodes library which will eventually contain all of the
3856 disassembly routines and opcode tables. At present, it only contains
3857 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3858 disassembler (binutils/objdump) to share these routines.
3860 The libiberty library is now copylefted under the GNU Library General
3861 Public License. This allows more liberal use, and was done so libg++
3862 can use it. This makes no difference to GDB, since the Library License
3863 grants all the rights from the General Public License.
3867 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3868 reference to the stabs symbol info used by the debugger. It is (as far
3869 as we know) the only published document on this fascinating topic. We
3870 encourage you to read it, compare it to the stabs information on your
3871 system, and send improvements on the document in general (to
3872 bug-gdb@prep.ai.mit.edu).
3874 And, of course, many bugs have been fixed.
3877 *** Changes in GDB-4.6:
3879 * Better support for C++ function names
3881 GDB now accepts as input the "demangled form" of C++ overloaded function
3882 names and member function names, and can do command completion on such names
3883 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3884 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3885 Make use of command completion, it is your friend.
3887 GDB also now accepts a variety of C++ mangled symbol formats. They are
3888 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3889 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3890 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3891 for the list of formats.
3893 * G++ symbol mangling problem
3895 Recent versions of gcc have a bug in how they emit debugging information for
3896 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3897 directory) can be applied to gcc to fix the problem. Alternatively, if you
3898 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3899 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3900 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3903 * New 'maintenance' command
3905 All of the commands related to hacking GDB internals have been moved out of
3906 the main command set, and now live behind the 'maintenance' command. This
3907 can also be abbreviated as 'mt'. The following changes were made:
3909 dump-me -> maintenance dump-me
3910 info all-breakpoints -> maintenance info breakpoints
3911 printmsyms -> maintenance print msyms
3912 printobjfiles -> maintenance print objfiles
3913 printpsyms -> maintenance print psymbols
3914 printsyms -> maintenance print symbols
3916 The following commands are new:
3918 maintenance demangle Call internal GDB demangler routine to
3919 demangle a C++ link name and prints the result.
3920 maintenance print type Print a type chain for a given symbol
3922 * Change to .gdbinit file processing
3924 We now read the $HOME/.gdbinit file before processing the argv arguments
3925 (e.g. reading symbol files or core files). This allows global parameters to
3926 be set, which will apply during the symbol reading. The ./.gdbinit is still
3927 read after argv processing.
3929 * New hosts supported
3931 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3933 GNU/Linux support i386-unknown-linux or linux
3935 We are also including code to support the HP/PA running BSD and HPUX. This
3936 is almost guaranteed not to work, as we didn't have time to test or build it
3937 for this release. We are including it so that the more adventurous (or
3938 masochistic) of you can play with it. We also had major problems with the
3939 fact that the compiler that we got from HP doesn't support the -g option.
3942 * New targets supported
3944 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3946 * More smarts about finding #include files
3948 GDB now remembers the compilation directory for all include files, and for
3949 all files from which C is generated (like yacc and lex sources). This
3950 greatly improves GDB's ability to find yacc/lex sources, and include files,
3951 especially if you are debugging your program from a directory different from
3952 the one that contains your sources.
3954 We also fixed a bug which caused difficulty with listing and setting
3955 breakpoints in include files which contain C code. (In the past, you had to
3956 try twice in order to list an include file that you hadn't looked at before.)
3958 * Interesting infernals change
3960 GDB now deals with arbitrary numbers of sections, where the symbols for each
3961 section must be relocated relative to that section's landing place in the
3962 target's address space. This work was needed to support ELF with embedded
3963 stabs used by Solaris-2.0.
3965 * Bug fixes (of course!)
3967 There have been loads of fixes for the following things:
3968 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3969 i960, stabs, DOS(GO32), procfs, etc...
3971 See the ChangeLog for details.
3973 *** Changes in GDB-4.5:
3975 * New machines supported (host and target)
3977 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3979 SGI Irix-4.x mips-sgi-irix4 or iris4
3981 * New malloc package
3983 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3984 Mmalloc is capable of handling mutiple heaps of memory. It is also
3985 capable of saving a heap to a file, and then mapping it back in later.
3986 This can be used to greatly speedup the startup of GDB by using a
3987 pre-parsed symbol table which lives in a mmalloc managed heap. For
3988 more details, please read mmalloc/mmalloc.texi.
3992 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3993 'help info proc' for details.
3995 * MIPS ecoff symbol table format
3997 The code that reads MIPS symbol table format is now supported on all hosts.
3998 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4001 * File name changes for MS-DOS
4003 Many files in the config directories have been renamed to make it easier to
4004 support GDB on MS-DOSe systems (which have very restrictive file name
4005 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4006 environment) is close to working but has some remaining problems. Note
4007 that debugging of DOS programs is not supported, due to limitations
4008 in the ``operating system'', but it can be used to host cross-debugging.
4010 * Cross byte order fixes
4012 Many fixes have been made to support cross debugging of Sparc and MIPS
4013 targets from hosts whose byte order differs.
4015 * New -mapped and -readnow options
4017 If memory-mapped files are available on your system through the 'mmap'
4018 system call, you can use the -mapped option on the `file' or
4019 `symbol-file' commands to cause GDB to write the symbols from your
4020 program into a reusable file. If the program you are debugging is
4021 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4022 Future GDB debugging sessions will notice the presence of this file,
4023 and will quickly map in symbol information from it, rather than reading
4024 the symbol table from the executable program. Using the '-mapped'
4025 option in a GDB `file' or `symbol-file' command has the same effect as
4026 starting GDB with the '-mapped' command-line option.
4028 You can cause GDB to read the entire symbol table immediately by using
4029 the '-readnow' option with any of the commands that load symbol table
4030 information (or on the GDB command line). This makes the command
4031 slower, but makes future operations faster.
4033 The -mapped and -readnow options are typically combined in order to
4034 build a `fred.syms' file that contains complete symbol information.
4035 A simple GDB invocation to do nothing but build a `.syms' file for future
4038 gdb -batch -nx -mapped -readnow programname
4040 The `.syms' file is specific to the host machine on which GDB is run.
4041 It holds an exact image of GDB's internal symbol table. It cannot be
4042 shared across multiple host platforms.
4044 * longjmp() handling
4046 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4047 siglongjmp() without losing control. This feature has not yet been ported to
4048 all systems. It currently works on many 386 platforms, all MIPS-based
4049 platforms (SGI, DECstation, etc), and Sun3/4.
4053 Preliminary work has been put in to support the new Solaris OS from Sun. At
4054 this time, it can control and debug processes, but it is not capable of
4059 As always, many many bug fixes. The major areas were with g++, and mipsread.
4060 People using the MIPS-based platforms should experience fewer mysterious
4061 crashes and trashed symbol tables.
4063 *** Changes in GDB-4.4:
4065 * New machines supported (host and target)
4067 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4069 BSD Reno on Vax vax-dec-bsd
4070 Ultrix on Vax vax-dec-ultrix
4072 * New machines supported (target)
4074 AMD 29000 embedded, using EBMON a29k-none-none
4078 GDB continues to improve its handling of C++. `References' work better.
4079 The demangler has also been improved, and now deals with symbols mangled as
4080 per the Annotated C++ Reference Guide.
4082 GDB also now handles `stabs' symbol information embedded in MIPS
4083 `ecoff' symbol tables. Since the ecoff format was not easily
4084 extensible to handle new languages such as C++, this appeared to be a
4085 good way to put C++ debugging info into MIPS binaries. This option
4086 will be supported in the GNU C compiler, version 2, when it is
4089 * New features for SVR4
4091 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4092 shared libraries. Debugging dynamically linked programs should present
4093 only minor differences from debugging statically linked programs.
4095 The `info proc' command will print out information about any process
4096 on an SVR4 system (including the one you are debugging). At the moment,
4097 it prints the address mappings of the process.
4099 If you bring up GDB on another SVR4 system, please send mail to
4100 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4102 * Better dynamic linking support in SunOS
4104 Reading symbols from shared libraries which contain debugging symbols
4105 now works properly. However, there remain issues such as automatic
4106 skipping of `transfer vector' code during function calls, which
4107 make it harder to debug code in a shared library, than to debug the
4108 same code linked statically.
4112 GDB is now using the latest `getopt' routines from the FSF. This
4113 version accepts the -- prefix for options with long names. GDB will
4114 continue to accept the old forms (-option and +option) as well.
4115 Various single letter abbreviations for options have been explicity
4116 added to the option table so that they won't get overshadowed in the
4117 future by other options that begin with the same letter.
4121 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4122 Many assorted bugs have been handled. Many more remain to be handled.
4123 See the various ChangeLog files (primarily in gdb and bfd) for details.
4126 *** Changes in GDB-4.3:
4128 * New machines supported (host and target)
4130 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4131 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4132 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4134 * Almost SCO Unix support
4136 We had hoped to support:
4137 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4138 (except for core file support), but we discovered very late in the release
4139 that it has problems with process groups that render gdb unusable. Sorry
4140 about that. I encourage people to fix it and post the fixes.
4142 * Preliminary ELF and DWARF support
4144 GDB can read ELF object files on System V Release 4, and can handle
4145 debugging records for C, in DWARF format, in ELF files. This support
4146 is preliminary. If you bring up GDB on another SVR4 system, please
4147 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4152 GDB now uses the latest `readline' library. One user-visible change
4153 is that two tabs will list possible command completions, which previously
4154 required typing M-? (meta-question mark, or ESC ?).
4158 The `stepi' bug that many of you noticed has been squashed.
4159 Many bugs in C++ have been handled. Many more remain to be handled.
4160 See the various ChangeLog files (primarily in gdb and bfd) for details.
4162 * State of the MIPS world (in case you wondered):
4164 GDB can understand the symbol tables emitted by the compilers
4165 supplied by most vendors of MIPS-based machines, including DEC. These
4166 symbol tables are in a format that essentially nobody else uses.
4168 Some versions of gcc come with an assembler post-processor called
4169 mips-tfile. This program is required if you want to do source-level
4170 debugging of gcc-compiled programs. I believe FSF does not ship
4171 mips-tfile with gcc version 1, but it will eventually come with gcc
4174 Debugging of g++ output remains a problem. g++ version 1.xx does not
4175 really support it at all. (If you're lucky, you should be able to get
4176 line numbers and stack traces to work, but no parameters or local
4177 variables.) With some work it should be possible to improve the
4180 When gcc version 2 is released, you will have somewhat better luck.
4181 However, even then you will get confusing results for inheritance and
4184 We will eventually provide full debugging of g++ output on
4185 DECstations. This will probably involve some kind of stabs-in-ecoff
4186 encapulation, but the details have not been worked out yet.
4189 *** Changes in GDB-4.2:
4191 * Improved configuration
4193 Only one copy of `configure' exists now, and it is not self-modifying.
4194 Porting BFD is simpler.
4198 The `step' and `next' commands now only stop at the first instruction
4199 of a source line. This prevents the multiple stops that used to occur
4200 in switch statements, for-loops, etc. `Step' continues to stop if a
4201 function that has debugging information is called within the line.
4205 Lots of small bugs fixed. More remain.
4207 * New host supported (not target)
4209 Intel 386 PC clone running Mach i386-none-mach
4212 *** Changes in GDB-4.1:
4214 * Multiple source language support
4216 GDB now has internal scaffolding to handle several source languages.
4217 It determines the type of each source file from its filename extension,
4218 and will switch expression parsing and number formatting to match the
4219 language of the function in the currently selected stack frame.
4220 You can also specifically set the language to be used, with
4221 `set language c' or `set language modula-2'.
4225 GDB now has preliminary support for the GNU Modula-2 compiler,
4226 currently under development at the State University of New York at
4227 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4228 continue through the fall of 1991 and into 1992.
4230 Other Modula-2 compilers are currently not supported, and attempting to
4231 debug programs compiled with them will likely result in an error as the
4232 symbol table is read. Feel free to work on it, though!
4234 There are hooks in GDB for strict type checking and range checking,
4235 in the `Modula-2 philosophy', but they do not currently work.
4239 GDB can now write to executable and core files (e.g. patch
4240 a variable's value). You must turn this switch on, specify
4241 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4242 by assigning a new value to a variable. Modifications take
4245 * Automatic SunOS shared library reading
4247 When you run your program, GDB automatically determines where its
4248 shared libraries (if any) have been loaded, and reads their symbols.
4249 The `share' command is no longer needed. This also works when
4250 examining core files.
4254 You can specify the number of lines that the `list' command shows.
4257 * New machines supported (host and target)
4259 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4260 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4261 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4263 * New hosts supported (not targets)
4265 IBM RT/PC: romp-ibm-aix or rtpc
4267 * New targets supported (not hosts)
4269 AMD 29000 embedded with COFF a29k-none-coff
4270 AMD 29000 embedded with a.out a29k-none-aout
4271 Ultracomputer remote kernel debug a29k-nyu-kern
4273 * New remote interfaces
4279 *** Changes in GDB-4.0:
4283 Wide output is wrapped at good places to make the output more readable.
4285 Gdb now supports cross-debugging from a host machine of one type to a
4286 target machine of another type. Communication with the target system
4287 is over serial lines. The ``target'' command handles connecting to the
4288 remote system; the ``load'' command will download a program into the
4289 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4290 also supports debugging of realtime processes running under VxWorks,
4291 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4292 stub on the target system.
4294 New CPUs supported include the AMD 29000 and Intel 960.
4296 GDB now reads object files and symbol tables via a ``binary file''
4297 library, which allows a single copy of GDB to debug programs of multiple
4298 object file types such as a.out and coff.
4300 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4301 refcard.dvi and refcard.ps are available to format it).
4304 * Control-Variable user interface simplified
4306 All variables that control the operation of the debugger can be set
4307 by the ``set'' command, and displayed by the ``show'' command.
4309 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4310 ``Show prompt'' produces the response:
4311 Gdb's prompt is new-gdb=>.
4313 What follows are the NEW set commands. The command ``help set'' will
4314 print a complete list of old and new set commands. ``help set FOO''
4315 will give a longer description of the variable FOO. ``show'' will show
4316 all of the variable descriptions and their current settings.
4318 confirm on/off: Enables warning questions for operations that are
4319 hard to recover from, e.g. rerunning the program while
4320 it is already running. Default is ON.
4322 editing on/off: Enables EMACS style command line editing
4323 of input. Previous lines can be recalled with
4324 control-P, the current line can be edited with control-B,
4325 you can search for commands with control-R, etc.
4328 history filename NAME: NAME is where the gdb command history
4329 will be stored. The default is .gdb_history,
4330 or the value of the environment variable
4333 history size N: The size, in commands, of the command history. The
4334 default is 256, or the value of the environment variable
4337 history save on/off: If this value is set to ON, the history file will
4338 be saved after exiting gdb. If set to OFF, the
4339 file will not be saved. The default is OFF.
4341 history expansion on/off: If this value is set to ON, then csh-like
4342 history expansion will be performed on
4343 command line input. The default is OFF.
4345 radix N: Sets the default radix for input and output. It can be set
4346 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4347 in the current radix, so "set radix 10" is always a no-op.
4349 height N: This integer value is the number of lines on a page. Default
4350 is 24, the current `stty rows'' setting, or the ``li#''
4351 setting from the termcap entry matching the environment
4354 width N: This integer value is the number of characters on a line.
4355 Default is 80, the current `stty cols'' setting, or the ``co#''
4356 setting from the termcap entry matching the environment
4359 Note: ``set screensize'' is obsolete. Use ``set height'' and
4360 ``set width'' instead.
4362 print address on/off: Print memory addresses in various command displays,
4363 such as stack traces and structure values. Gdb looks
4364 more ``symbolic'' if you turn this off; it looks more
4365 ``machine level'' with it on. Default is ON.
4367 print array on/off: Prettyprint arrays. New convenient format! Default
4370 print demangle on/off: Print C++ symbols in "source" form if on,
4373 print asm-demangle on/off: Same, for assembler level printouts
4376 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4379 * Support for Epoch Environment.
4381 The epoch environment is a version of Emacs v18 with windowing. One
4382 new command, ``inspect'', is identical to ``print'', except that if you
4383 are running in the epoch environment, the value is printed in its own
4387 * Support for Shared Libraries
4389 GDB can now debug programs and core files that use SunOS shared libraries.
4390 Symbols from a shared library cannot be referenced
4391 before the shared library has been linked with the program (this
4392 happens after you type ``run'' and before the function main() is entered).
4393 At any time after this linking (including when examining core files
4394 from dynamically linked programs), gdb reads the symbols from each
4395 shared library when you type the ``sharedlibrary'' command.
4396 It can be abbreviated ``share''.
4398 sharedlibrary REGEXP: Load shared object library symbols for files
4399 matching a unix regular expression. No argument
4400 indicates to load symbols for all shared libraries.
4402 info sharedlibrary: Status of loaded shared libraries.
4407 A watchpoint stops execution of a program whenever the value of an
4408 expression changes. Checking for this slows down execution
4409 tremendously whenever you are in the scope of the expression, but is
4410 quite useful for catching tough ``bit-spreader'' or pointer misuse
4411 problems. Some machines such as the 386 have hardware for doing this
4412 more quickly, and future versions of gdb will use this hardware.
4414 watch EXP: Set a watchpoint (breakpoint) for an expression.
4416 info watchpoints: Information about your watchpoints.
4418 delete N: Deletes watchpoint number N (same as breakpoints).
4419 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4420 enable N: Re-enables watchpoint number N (same as breakpoints).
4423 * C++ multiple inheritance
4425 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4428 * C++ exception handling
4430 Gdb now supports limited C++ exception handling. Besides the existing
4431 ability to breakpoint on an exception handler, gdb can breakpoint on
4432 the raising of an exception (before the stack is peeled back to the
4435 catch FOO: If there is a FOO exception handler in the dynamic scope,
4436 set a breakpoint to catch exceptions which may be raised there.
4437 Multiple exceptions (``catch foo bar baz'') may be caught.
4439 info catch: Lists all exceptions which may be caught in the
4440 current stack frame.
4443 * Minor command changes
4445 The command ``call func (arg, arg, ...)'' now acts like the print
4446 command, except it does not print or save a value if the function's result
4447 is void. This is similar to dbx usage.
4449 The ``up'' and ``down'' commands now always print the frame they end up
4450 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4451 frames without printing.
4453 * New directory command
4455 'dir' now adds directories to the FRONT of the source search path.
4456 The path starts off empty. Source files that contain debug information
4457 about the directory in which they were compiled can be found even
4458 with an empty path; Sun CC and GCC include this information. If GDB can't
4459 find your source file in the current directory, type "dir .".
4461 * Configuring GDB for compilation
4463 For normal use, type ``./configure host''. See README or gdb.texinfo
4466 GDB now handles cross debugging. If you are remotely debugging between
4467 two different machines, type ``./configure host -target=targ''.
4468 Host is the machine where GDB will run; targ is the machine
4469 where the program that you are debugging will run.