1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.9
6 * The "info source" command now displays the producer string if it was
7 present in the debug info. This typically includes the compiler version
8 and may include things like its command line arguments.
12 ** gdb.Objfile objects have a new attribute "username",
13 which is the name of the objfile as specified by the user,
14 without, for example, resolving symlinks.
18 maint print symbol-cache
19 Print the contents of the symbol cache.
21 maint print symbol-cache-statistics
22 Print statistics of symbol cache usage.
24 maint flush-symbol-cache
25 Flush the contents of the symbol cache.
29 Start branch trace recording using Branch Trace Store (BTS) format.
35 Set the maximum number of candidates to be considered during
36 completion. The default value is 200. This limit allows GDB
37 to avoid generating large completion lists, the computation of
38 which can cause the debugger to become temporarily unresponsive.
40 maint set symbol-cache-size
41 maint show symbol-cache-size
42 Control the size of the symbol cache.
44 set|show record btrace bts buffer-size
45 Set and show the size of the ring buffer used for branch tracing in
47 The obtained size may differ from the requested size. Use "info
48 record" to see the obtained buffer size.
50 * The command 'thread apply all' can now support new option '-ascending'
51 to call its specified command for all threads in ascending order.
53 * Python/Guile scripting
55 ** GDB now supports auto-loading of Python/Guile scripts contained in the
56 special section named `.debug_gdb_scripts'.
60 qXfer:btrace-conf:read
61 Return the branch trace configuration for the current thread.
64 Set the requested ring buffer size for branch tracing in BTS format.
66 * The info record command now shows the recording format and the
67 branch tracing configuration for the current thread when using
68 the btrace record target.
69 For the BTS format, it shows the ring buffer size.
71 *** Changes in GDB 7.9
73 * GDB now supports hardware watchpoints on x86 GNU Hurd.
77 ** You can now access frame registers from Python scripts.
78 ** New attribute 'producer' for gdb.Symtab objects.
79 ** gdb.Objfile objects have a new attribute "progspace",
80 which is the gdb.Progspace object of the containing program space.
81 ** gdb.Objfile objects have a new attribute "owner".
82 ** gdb.Objfile objects have a new attribute "build_id",
83 which is the build ID generated when the file was built.
84 ** gdb.Objfile objects have a new method "add_separate_debug_file".
85 ** A new event "gdb.clear_objfiles" has been added, triggered when
86 selecting a new file to debug.
87 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
88 ** New function gdb.lookup_objfile.
90 New events which are triggered when GDB modifies the state of the
93 ** gdb.events.inferior_call_pre: Function call is about to be made.
94 ** gdb.events.inferior_call_post: Function call has just been made.
95 ** gdb.events.memory_changed: A memory location has been altered.
96 ** gdb.events.register_changed: A register has been altered.
98 * New Python-based convenience functions:
100 ** $_caller_is(name [, number_of_frames])
101 ** $_caller_matches(regexp [, number_of_frames])
102 ** $_any_caller_is(name [, number_of_frames])
103 ** $_any_caller_matches(regexp [, number_of_frames])
105 * GDB now supports the compilation and injection of source code into
106 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
107 to compile the source code to object code, and if successful, inject
108 and execute that code within the current context of the inferior.
109 Currently the C language is supported. The commands used to
110 interface with this new feature are:
112 compile code [-raw|-r] [--] [source code]
113 compile file [-raw|-r] filename
117 demangle [-l language] [--] name
118 Demangle "name" in the specified language, or the current language
119 if elided. This command is renamed from the "maint demangle" command.
120 The latter is kept as a no-op to avoid "maint demangle" being interpreted
121 as "maint demangler-warning".
123 queue-signal signal-name-or-number
124 Queue a signal to be delivered to the thread when it is resumed.
126 add-auto-load-scripts-directory directory
127 Add entries to the list of directories from which to load auto-loaded
130 maint print user-registers
131 List all currently available "user" registers.
133 compile code [-r|-raw] [--] [source code]
134 Compile, inject, and execute in the inferior the executable object
135 code produced by compiling the provided source code.
137 compile file [-r|-raw] filename
138 Compile and inject into the inferior the executable object code
139 produced by compiling the source code stored in the filename
142 * On resume, GDB now always passes the signal the program had stopped
143 for to the thread the signal was sent to, even if the user changed
144 threads before resuming. Previously GDB would often (but not
145 always) deliver the signal to the thread that happens to be current
148 * Conversely, the "signal" command now consistently delivers the
149 requested signal to the current thread. GDB now asks for
150 confirmation if the program had stopped for a signal and the user
151 switched threads meanwhile.
153 * "breakpoint always-inserted" modes "off" and "auto" merged.
155 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
156 won't remove breakpoints from the target until all threads stop,
157 even in non-stop mode. The "auto" mode has been removed, and "off"
158 is now the default mode.
162 set debug symbol-lookup
163 show debug symbol-lookup
164 Control display of debugging info regarding symbol lookup.
168 ** The -list-thread-groups command outputs an exit-code field for
169 inferiors that have exited.
173 MIPS SDE mips*-sde*-elf*
177 Support for these obsolete configurations has been removed.
179 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
180 SGI Irix-5.x mips-*-irix5*
181 SGI Irix-6.x mips-*-irix6*
182 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
183 VAX running Ultrix vax-*-ultrix*
185 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
186 and "assf"), have been removed. Use the "sharedlibrary" command, or
187 its alias "share", instead.
189 *** Changes in GDB 7.8
191 * New command line options
194 This is an alias for the --data-directory option.
196 * GDB supports printing and modifying of variable length automatic arrays
197 as specified in ISO C99.
199 * The ARM simulator now supports instruction level tracing
200 with or without disassembly.
204 GDB now has support for scripting using Guile. Whether this is
205 available is determined at configure time.
206 Guile version 2.0 or greater is required.
207 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
209 * New commands (for set/show, see "New options" below)
213 Invoke CODE by passing it to the Guile interpreter.
217 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
219 info auto-load guile-scripts [regexp]
220 Print the list of automatically loaded Guile scripts.
222 * The source command is now capable of sourcing Guile scripts.
223 This feature is dependent on the debugger being built with Guile support.
227 set print symbol-loading (off|brief|full)
228 show print symbol-loading
229 Control whether to print informational messages when loading symbol
230 information for a file. The default is "full", but when debugging
231 programs with large numbers of shared libraries the amount of output
234 set guile print-stack (none|message|full)
235 show guile print-stack
236 Show a stack trace when an error is encountered in a Guile script.
238 set auto-load guile-scripts (on|off)
239 show auto-load guile-scripts
240 Control auto-loading of Guile script files.
242 maint ada set ignore-descriptive-types (on|off)
243 maint ada show ignore-descriptive-types
244 Control whether the debugger should ignore descriptive types in Ada
245 programs. The default is not to ignore the descriptive types. See
246 the user manual for more details on descriptive types and the intended
247 usage of this option.
249 set auto-connect-native-target
251 Control whether GDB is allowed to automatically connect to the
252 native target for the run, attach, etc. commands when not connected
253 to any target yet. See also "target native" below.
255 set record btrace replay-memory-access (read-only|read-write)
256 show record btrace replay-memory-access
257 Control what memory accesses are allowed during replay.
259 maint set target-async (on|off)
260 maint show target-async
261 This controls whether GDB targets operate in synchronous or
262 asynchronous mode. Normally the default is asynchronous, if it is
263 available; but this can be changed to more easily debug problems
264 occurring only in synchronous mode.
266 set mi-async (on|off)
268 Control whether MI asynchronous mode is preferred. This supersedes
269 "set target-async" of previous GDB versions.
271 * "set target-async" is deprecated as a CLI option and is now an alias
272 for "set mi-async" (only puts MI into async mode).
274 * Background execution commands (e.g., "c&", "s&", etc.) are now
275 possible ``out of the box'' if the target supports them. Previously
276 the user would need to explicitly enable the possibility with the
277 "set target-async on" command.
279 * New features in the GDB remote stub, GDBserver
281 ** New option --debug-format=option1[,option2,...] allows one to add
282 additional text to each output. At present only timestamps
283 are supported: --debug-format=timestamps.
284 Timestamps can also be turned on with the
285 "monitor set debug-format timestamps" command from GDB.
287 * The 'record instruction-history' command now starts counting instructions
288 at one. This also affects the instruction ranges reported by the
289 'record function-call-history' command when given the /i modifier.
291 * The command 'record function-call-history' supports a new modifier '/c' to
292 indent the function names based on their call stack depth.
293 The fields for the '/i' and '/l' modifier have been reordered.
294 The source line range is now prefixed with 'at'.
295 The instruction range is now prefixed with 'inst'.
296 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
297 "record instruction-history" and "list" commands.
299 * The ranges given as arguments to the 'record function-call-history' and
300 'record instruction-history' commands are now inclusive.
302 * The btrace record target now supports the 'record goto' command.
303 For locations inside the execution trace, the back trace is computed
304 based on the information stored in the execution trace.
306 * The btrace record target supports limited reverse execution and replay.
307 The target does not record data and therefore does not allow reading
310 * The "catch syscall" command now works on s390*-linux* targets.
312 * The "compare-sections" command is no longer specific to target
313 remote. It now works with all targets.
315 * All native targets are now consistently called "native".
316 Consequently, the "target child", "target GNU", "target djgpp",
317 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
318 commands have been replaced with "target native". The QNX/NTO port
319 leaves the "procfs" target in place and adds a "native" target for
320 consistency with other ports. The impact on users should be minimal
321 as these commands previously either throwed an error, or were
322 no-ops. The target's name is visible in the output of the following
323 commands: "help target", "info target", "info files", "maint print
326 * The "target native" command now connects to the native target. This
327 can be used to launch native programs even when "set
328 auto-connect-native-target" is set to off.
330 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
332 * Support for Intel(R) AVX-512 registers on GNU/Linux.
333 Support displaying and modifying Intel(R) AVX-512 registers
334 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
338 qXfer:btrace:read's annex
339 The qXfer:btrace:read packet supports a new annex 'delta' to read
340 branch trace incrementally.
344 ** Valid Python operations on gdb.Value objects representing
345 structs/classes invoke the corresponding overloaded operators if
347 ** New `Xmethods' feature in the Python API. Xmethods are
348 additional methods or replacements for existing methods of a C++
349 class. This feature is useful for those cases where a method
350 defined in C++ source code could be inlined or optimized out by
351 the compiler, making it unavailable to GDB.
354 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
356 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
357 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
358 its alias "share", instead.
360 * The commands "set remotebaud" and "show remotebaud" are no longer
361 supported. Use "set serial baud" and "show serial baud" (respectively)
366 ** A new option "-gdb-set mi-async" replaces "-gdb-set
367 target-async". The latter is left as a deprecated alias of the
368 former for backward compatibility. If the target supports it,
369 CLI background execution commands are now always possible by
370 default, independently of whether the frontend stated a
371 preference for asynchronous execution with "-gdb-set mi-async".
372 Previously "-gdb-set target-async off" affected both MI execution
373 commands and CLI execution commands.
375 *** Changes in GDB 7.7
377 * Improved support for process record-replay and reverse debugging on
378 arm*-linux* targets. Support for thumb32 and syscall instruction
379 recording has been added.
381 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
383 * GDB now supports Fission DWP file format version 2.
384 http://gcc.gnu.org/wiki/DebugFission
386 * New convenience function "$_isvoid", to check whether an expression
387 is void. A void expression is an expression where the type of the
388 result is "void". For example, some convenience variables may be
389 "void" when evaluated (e.g., "$_exitcode" before the execution of
390 the program being debugged; or an undefined convenience variable).
391 Another example, when calling a function whose return type is
394 * The "maintenance print objfiles" command now takes an optional regexp.
396 * The "catch syscall" command now works on arm*-linux* targets.
398 * GDB now consistently shows "<not saved>" when printing values of
399 registers the debug info indicates have not been saved in the frame
400 and there's nowhere to retrieve them from
401 (callee-saved/call-clobbered registers):
406 (gdb) info registers rax
409 Before, the former would print "<optimized out>", and the latter
410 "*value not available*".
412 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
417 ** Frame filters and frame decorators have been added.
418 ** Temporary breakpoints are now supported.
419 ** Line tables representation has been added.
420 ** New attribute 'parent_type' for gdb.Field objects.
421 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
422 ** New attribute 'name' for gdb.Type objects.
426 Nios II ELF nios2*-*-elf
427 Nios II GNU/Linux nios2*-*-linux
428 Texas Instruments MSP430 msp430*-*-elf
430 * Removed native configurations
432 Support for these a.out NetBSD and OpenBSD obsolete configurations has
433 been removed. ELF variants of these configurations are kept supported.
435 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
436 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
437 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
438 i[34567]86-*-openbsd3.[0-3]
439 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
440 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
441 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
445 Like "catch throw", but catches a re-thrown exception.
447 Renamed from old "maint check-symtabs".
449 Perform consistency checks on symtabs.
451 Expand symtabs matching an optional regexp.
454 Display the details of GDB configure-time options.
456 maint set|show per-command
457 maint set|show per-command space
458 maint set|show per-command time
459 maint set|show per-command symtab
460 Enable display of per-command gdb resource usage.
462 remove-symbol-file FILENAME
463 remove-symbol-file -a ADDRESS
464 Remove a symbol file added via add-symbol-file. The file to remove
465 can be identified by its filename or by an address that lies within
466 the boundaries of this symbol file in memory.
469 info exceptions REGEXP
470 Display the list of Ada exceptions defined in the program being
471 debugged. If provided, only the exceptions whose names match REGEXP
476 set debug symfile off|on
478 Control display of debugging info regarding reading symbol files and
479 symbol tables within those files
481 set print raw frame-arguments
482 show print raw frame-arguments
483 Set/show whether to print frame arguments in raw mode,
484 disregarding any defined pretty-printers.
486 set remote trace-status-packet
487 show remote trace-status-packet
488 Set/show the use of remote protocol qTStatus packet.
492 Control display of debugging messages related to Nios II targets.
496 Control whether target-assisted range stepping is enabled.
498 set startup-with-shell
499 show startup-with-shell
500 Specifies whether Unix child processes are started via a shell or
505 Use the target memory cache for accesses to the code segment. This
506 improves performance of remote debugging (particularly disassembly).
508 * You can now use a literal value 'unlimited' for options that
509 interpret 0 or -1 as meaning "unlimited". E.g., "set
510 trace-buffer-size unlimited" is now an alias for "set
511 trace-buffer-size -1" and "set height unlimited" is now an alias for
514 * The "set debug symtab-create" debugging option of GDB has been changed to
515 accept a verbosity level. 0 means "off", 1 provides basic debugging
516 output, and values of 2 or greater provides more verbose output.
518 * New command-line options
520 Display the details of GDB configure-time options.
522 * The command 'tsave' can now support new option '-ctf' to save trace
523 buffer in Common Trace Format.
525 * Newly installed $prefix/bin/gcore acts as a shell interface for the
528 * GDB now implements the the C++ 'typeid' operator.
530 * The new convenience variable $_exception holds the exception being
531 thrown or caught at an exception-related catchpoint.
533 * The exception-related catchpoints, like "catch throw", now accept a
534 regular expression which can be used to filter exceptions by type.
536 * The new convenience variable $_exitsignal is automatically set to
537 the terminating signal number when the program being debugged dies
538 due to an uncaught signal.
542 ** All MI commands now accept an optional "--language" option.
543 Support for this feature can be verified by using the "-list-features"
544 command, which should contain "language-option".
546 ** The new command -info-gdb-mi-command allows the user to determine
547 whether a GDB/MI command is supported or not.
549 ** The "^error" result record returned when trying to execute an undefined
550 GDB/MI command now provides a variable named "code" whose content is the
551 "undefined-command" error code. Support for this feature can be verified
552 by using the "-list-features" command, which should contain
553 "undefined-command-error-code".
555 ** The -trace-save MI command can optionally save trace buffer in Common
558 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
560 ** The command -data-list-register-values now accepts an optional
561 "--skip-unavailable" option. When used, only the available registers
564 ** The new command -trace-frame-collected dumps collected variables,
565 computed expressions, tvars, memory and registers in a traceframe.
567 ** The commands -stack-list-locals, -stack-list-arguments and
568 -stack-list-variables now accept an option "--skip-unavailable".
569 When used, only the available locals or arguments are displayed.
571 ** The -exec-run command now accepts an optional "--start" option.
572 When used, the command follows the same semantics as the "start"
573 command, stopping the program's execution at the start of its
574 main subprogram. Support for this feature can be verified using
575 the "-list-features" command, which should contain
576 "exec-run-start-option".
578 ** The new commands -catch-assert and -catch-exceptions insert
579 catchpoints stopping the program when Ada exceptions are raised.
581 ** The new command -info-ada-exceptions provides the equivalent of
582 the new "info exceptions" command.
584 * New system-wide configuration scripts
585 A GDB installation now provides scripts suitable for use as system-wide
586 configuration scripts for the following systems:
590 * GDB now supports target-assigned range stepping with remote targets.
591 This improves the performance of stepping source lines by reducing
592 the number of control packets from/to GDB. See "New remote packets"
595 * GDB now understands the element 'tvar' in the XML traceframe info.
596 It has the id of the collected trace state variables.
598 * On S/390 targets that provide the transactional-execution feature,
599 the program interruption transaction diagnostic block (TDB) is now
600 represented as a number of additional "registers" in GDB.
606 The vCont packet supports a new 'r' action, that tells the remote
607 stub to step through an address range itself, without GDB
608 involvemement at each single-step.
610 qXfer:libraries-svr4:read's annex
611 The previously unused annex of the qXfer:libraries-svr4:read packet
612 is now used to support passing an argument list. The remote stub
613 reports support for this argument list to GDB's qSupported query.
614 The defined arguments are "start" and "prev", used to reduce work
615 necessary for library list updating, resulting in significant
618 * New features in the GDB remote stub, GDBserver
620 ** GDBserver now supports target-assisted range stepping. Currently
621 enabled on x86/x86_64 GNU/Linux targets.
623 ** GDBserver now adds element 'tvar' in the XML in the reply to
624 'qXfer:traceframe-info:read'. It has the id of the collected
625 trace state variables.
627 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
630 * New 'z' formatter for printing and examining memory, this displays the
631 value as hexadecimal zero padded on the left to the size of the type.
633 * GDB can now use Windows x64 unwinding data.
635 * The "set remotebaud" command has been replaced by "set serial baud".
636 Similarly, "show remotebaud" has been replaced by "show serial baud".
637 The "set remotebaud" and "show remotebaud" commands are still available
638 to provide backward compatibility with older versions of GDB.
640 *** Changes in GDB 7.6
642 * Target record has been renamed to record-full.
643 Record/replay is now enabled with the "record full" command.
644 This also affects settings that are associated with full record/replay
645 that have been moved from "set/show record" to "set/show record full":
647 set|show record full insn-number-max
648 set|show record full stop-at-limit
649 set|show record full memory-query
651 * A new record target "record-btrace" has been added. The new target
652 uses hardware support to record the control-flow of a process. It
653 does not support replaying the execution, but it implements the
654 below new commands for investigating the recorded execution log.
655 This new recording method can be enabled using:
659 The "record-btrace" target is only available on Intel Atom processors
660 and requires a Linux kernel 2.6.32 or later.
662 * Two new commands have been added for record/replay to give information
663 about the recorded execution without having to replay the execution.
664 The commands are only supported by "record btrace".
666 record instruction-history prints the execution history at
667 instruction granularity
669 record function-call-history prints the execution history at
672 * New native configurations
674 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
675 FreeBSD/powerpc powerpc*-*-freebsd
676 x86_64/Cygwin x86_64-*-cygwin*
677 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
681 ARM AArch64 aarch64*-*-elf
682 ARM AArch64 GNU/Linux aarch64*-*-linux
683 Lynx 178 PowerPC powerpc-*-lynx*178
684 x86_64/Cygwin x86_64-*-cygwin*
685 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
687 * If the configured location of system.gdbinit file (as given by the
688 --with-system-gdbinit option at configure time) is in the
689 data-directory (as specified by --with-gdb-datadir at configure
690 time) or in one of its subdirectories, then GDB will look for the
691 system-wide init file in the directory specified by the
692 --data-directory command-line option.
694 * New command line options:
696 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
697 other initialization files, unlike -nx which disables all of them.
699 * Removed command line options
701 -epoch This was used by the gdb mode in Epoch, an ancient fork of
704 * The 'ptype' and 'whatis' commands now accept an argument to control
707 * 'info proc' now works on some core files.
711 ** Vectors can be created with gdb.Type.vector.
713 ** Python's atexit.register now works in GDB.
715 ** Types can be pretty-printed via a Python API.
717 ** Python 3 is now supported (in addition to Python 2.4 or later)
719 ** New class gdb.Architecture exposes GDB's internal representation
720 of architecture in the Python API.
722 ** New method Frame.architecture returns the gdb.Architecture object
723 corresponding to the frame's architecture.
725 * New Python-based convenience functions:
727 ** $_memeq(buf1, buf2, length)
728 ** $_streq(str1, str2)
730 ** $_regex(str, regex)
732 * The 'cd' command now defaults to using '~' (the home directory) if not
735 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
736 default for GCC since November 2000.
738 * The command 'forward-search' can now be abbreviated as 'fo'.
740 * The command 'info tracepoints' can now display 'installed on target'
741 or 'not installed on target' for each non-pending location of tracepoint.
743 * New configure options
745 --enable-libmcheck/--disable-libmcheck
746 By default, development versions are built with -lmcheck on hosts
747 that support it, in order to help track memory corruption issues.
748 Release versions, on the other hand, are built without -lmcheck
749 by default. The --enable-libmcheck/--disable-libmcheck configure
750 options allow the user to override that default.
751 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
752 This configure option allows the user to build GDB with
753 libbabeltrace using which GDB can read Common Trace Format data.
755 * New commands (for set/show, see "New options" below)
758 Catch signals. This is similar to "handle", but allows commands and
759 conditions to be attached.
762 List the BFDs known to GDB.
764 python-interactive [command]
766 Start a Python interactive prompt, or evaluate the optional command
767 and print the result of expressions.
770 "py" is a new alias for "python".
772 enable type-printer [name]...
773 disable type-printer [name]...
774 Enable or disable type printers.
778 ** For the Renesas Super-H architecture, the "regs" command has been removed
779 (has been deprecated in GDB 7.5), and "info all-registers" should be used
784 set print type methods (on|off)
785 show print type methods
786 Control whether method declarations are displayed by "ptype".
787 The default is to show them.
789 set print type typedefs (on|off)
790 show print type typedefs
791 Control whether typedef definitions are displayed by "ptype".
792 The default is to show them.
794 set filename-display basename|relative|absolute
795 show filename-display
796 Control the way in which filenames is displayed.
797 The default is "relative", which preserves previous behavior.
799 set trace-buffer-size
800 show trace-buffer-size
801 Request target to change the size of trace buffer.
803 set remote trace-buffer-size-packet auto|on|off
804 show remote trace-buffer-size-packet
805 Control the use of the remote protocol `QTBuffer:size' packet.
809 Control display of debugging messages related to ARM AArch64.
812 set debug coff-pe-read
813 show debug coff-pe-read
814 Control display of debugging messages related to reading of COFF/PE
819 Control display of debugging messages related to Mach-O symbols
822 set debug notification
823 show debug notification
824 Control display of debugging info for async remote notification.
828 ** Command parameter changes are now notified using new async record
829 "=cmd-param-changed".
830 ** Trace frame changes caused by command "tfind" are now notified using
831 new async record "=traceframe-changed".
832 ** The creation, deletion and modification of trace state variables
833 are now notified using new async records "=tsv-created",
834 "=tsv-deleted" and "=tsv-modified".
835 ** The start and stop of process record are now notified using new
836 async record "=record-started" and "=record-stopped".
837 ** Memory changes are now notified using new async record
839 ** The data-disassemble command response will include a "fullname" field
840 containing the absolute file name when source has been requested.
841 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
842 command, to allow pattern filling of memory areas.
843 ** New commands "-catch-load"/"-catch-unload" added for intercepting
844 library load/unload events.
845 ** The response to breakpoint commands and breakpoint async records
846 includes an "installed" field containing a boolean state about each
847 non-pending tracepoint location is whether installed on target or not.
848 ** Output of the "-trace-status" command includes a "trace-file" field
849 containing the name of the trace file being examined. This field is
850 optional, and only present when examining a trace file.
851 ** The "fullname" field is now always present along with the "file" field,
852 even if the file cannot be found by GDB.
854 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
855 You must have the LZMA library available when configuring GDB for this
856 feature to be enabled. For more information, see:
857 http://fedoraproject.org/wiki/Features/MiniDebugInfo
862 Set the size of trace buffer. The remote stub reports support for this
863 packet to gdb's qSupported query.
866 Enable Branch Trace Store (BTS)-based branch tracing for the current
867 thread. The remote stub reports support for this packet to gdb's
871 Disable branch tracing for the current thread. The remote stub reports
872 support for this packet to gdb's qSupported query.
875 Read the traced branches for the current thread. The remote stub
876 reports support for this packet to gdb's qSupported query.
878 *** Changes in GDB 7.5
880 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
881 for more x32 ABI info.
883 * GDB now supports access to MIPS DSP registers on Linux targets.
885 * GDB now supports debugging microMIPS binaries.
887 * The "info os" command on GNU/Linux can now display information on
888 several new classes of objects managed by the operating system:
889 "info os procgroups" lists process groups
890 "info os files" lists file descriptors
891 "info os sockets" lists internet-domain sockets
892 "info os shm" lists shared-memory regions
893 "info os semaphores" lists semaphores
894 "info os msg" lists message queues
895 "info os modules" lists loaded kernel modules
897 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
898 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
899 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
900 options and inspect the probe arguments using the new $_probe_arg family
901 of convenience variables. You can obtain more information about SystemTap
902 in <http://sourceware.org/systemtap/>.
904 * GDB now supports reversible debugging on ARM, it allows you to
905 debug basic ARM and THUMB instructions, and provides
906 record/replay support.
908 * The option "symbol-reloading" has been deleted as it is no longer used.
912 ** GDB commands implemented in Python can now be put in command class
915 ** The "maint set python print-stack on|off" is now deleted.
917 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
918 apply "flag enum"-style pretty-printing to any enum.
920 ** gdb.lookup_symbol can now work when there is no current frame.
922 ** gdb.Symbol now has a 'line' attribute, holding the line number in
923 the source at which the symbol was defined.
925 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
926 method 'value'. The former indicates whether the symbol needs a
927 frame in order to compute its value, and the latter computes the
930 ** A new method 'referenced_value' on gdb.Value objects which can
931 dereference pointer as well as C++ reference values.
933 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
934 which return the global and static blocks (as gdb.Block objects),
935 of the underlying symbol table, respectively.
937 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
938 object associated with a PC value.
940 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
941 of the address range occupied by code for the current source line.
943 * Go language support.
944 GDB now supports debugging programs written in the Go programming
947 * GDBserver now supports stdio connections.
948 E.g. (gdb) target remote | ssh myhost gdbserver - hello
950 * The binary "gdbtui" can no longer be built or installed.
951 Use "gdb -tui" instead.
953 * GDB will now print "flag" enums specially. A flag enum is one where
954 all the enumerator values have no bits in common when pairwise
955 "and"ed. When printing a value whose type is a flag enum, GDB will
956 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
957 (gdb) print (enum E) 3
960 * The filename part of a linespec will now match trailing components
961 of a source file name. For example, "break gcc/expr.c:1000" will
962 now set a breakpoint in build/gcc/expr.c, but not
965 * The "info proc" and "generate-core-file" commands will now also
966 work on remote targets connected to GDBserver on Linux.
968 * The command "info catch" has been removed. It has been disabled
971 * The "catch exception" and "catch assert" commands now accept
972 a condition at the end of the command, much like the "break"
973 command does. For instance:
975 (gdb) catch exception Constraint_Error if Barrier = True
977 Previously, it was possible to add a condition to such catchpoints,
978 but it had to be done as a second step, after the catchpoint had been
979 created, using the "condition" command.
981 * The "info static-tracepoint-marker" command will now also work on
982 native Linux targets with in-process agent.
984 * GDB can now set breakpoints on inlined functions.
986 * The .gdb_index section has been updated to include symbols for
987 inlined functions. GDB will ignore older .gdb_index sections by
988 default, which could cause symbol files to be loaded more slowly
989 until their .gdb_index sections can be recreated. The new command
990 "set use-deprecated-index-sections on" will cause GDB to use any older
991 .gdb_index sections it finds. This will restore performance, but the
992 ability to set breakpoints on inlined functions will be lost in symbol
993 files with older .gdb_index sections.
995 The .gdb_index section has also been updated to record more information
996 about each symbol. This speeds up the "info variables", "info functions"
997 and "info types" commands when used with programs having the .gdb_index
998 section, as well as speeding up debugging with shared libraries using
999 the .gdb_index section.
1001 * Ada support for GDB/MI Variable Objects has been added.
1003 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1008 ** New command -info-os is the MI equivalent of "info os".
1010 ** Output logs ("set logging" and related) now include MI output.
1014 ** "set use-deprecated-index-sections on|off"
1015 "show use-deprecated-index-sections on|off"
1016 Controls the use of deprecated .gdb_index sections.
1018 ** "catch load" and "catch unload" can be used to stop when a shared
1019 library is loaded or unloaded, respectively.
1021 ** "enable count" can be used to auto-disable a breakpoint after
1024 ** "info vtbl" can be used to show the virtual method tables for
1025 C++ and Java objects.
1027 ** "explore" and its sub commands "explore value" and "explore type"
1028 can be used to recursively explore values and types of
1029 expressions. These commands are available only if GDB is
1030 configured with '--with-python'.
1032 ** "info auto-load" shows status of all kinds of auto-loaded files,
1033 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1034 sequences of commands files, "info auto-load python-scripts"
1035 shows status of auto-loading Python script files,
1036 "info auto-load local-gdbinit" shows status of loading init file
1037 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1038 status of inferior specific thread debugging shared library loading.
1040 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1041 and "show auto-load-scripts" commands have been deprecated, use their
1042 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1043 and "show auto-load python-scripts" counterparts instead.
1045 ** "dprintf location,format,args..." creates a dynamic printf, which
1046 is basically a breakpoint that does a printf and immediately
1047 resumes your program's execution, so it is like a printf that you
1048 can insert dynamically at runtime instead of at compiletime.
1050 ** "set print symbol"
1052 Controls whether GDB attempts to display the symbol, if any,
1053 corresponding to addresses it prints. This defaults to "on", but
1054 you can set it to "off" to restore GDB's previous behavior.
1056 * Deprecated commands
1058 ** For the Renesas Super-H architecture, the "regs" command has been
1059 deprecated, and "info all-registers" should be used instead.
1063 Renesas RL78 rl78-*-elf
1064 HP OpenVMS ia64 ia64-hp-openvms*
1066 * GDBserver supports evaluation of breakpoint conditions. When
1067 support is advertised by GDBserver, GDB may be told to send the
1068 breakpoint conditions in bytecode form to GDBserver. GDBserver
1069 will only report the breakpoint trigger to GDB when its condition
1074 set mips compression
1075 show mips compression
1076 Select the compressed ISA encoding used in functions that have no symbol
1077 information available. The encoding can be set to either of:
1080 and is updated automatically from ELF file flags if available.
1082 set breakpoint condition-evaluation
1083 show breakpoint condition-evaluation
1084 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1085 GDBserver ("target"). Default option "auto" chooses the most efficient
1087 This option can improve debugger efficiency depending on the speed of the
1091 Disable auto-loading globally.
1094 Show auto-loading setting of all kinds of auto-loaded files.
1096 set auto-load gdb-scripts on|off
1097 show auto-load gdb-scripts
1098 Control auto-loading of GDB canned sequences of commands files.
1100 set auto-load python-scripts on|off
1101 show auto-load python-scripts
1102 Control auto-loading of Python script files.
1104 set auto-load local-gdbinit on|off
1105 show auto-load local-gdbinit
1106 Control loading of init file (.gdbinit) from current directory.
1108 set auto-load libthread-db on|off
1109 show auto-load libthread-db
1110 Control auto-loading of inferior specific thread debugging shared library.
1112 set auto-load scripts-directory <dir1>[:<dir2>...]
1113 show auto-load scripts-directory
1114 Set a list of directories from which to load auto-loaded scripts.
1115 Automatically loaded Python scripts and GDB scripts are located in one
1116 of the directories listed by this option.
1117 The delimiter (':' above) may differ according to the host platform.
1119 set auto-load safe-path <dir1>[:<dir2>...]
1120 show auto-load safe-path
1121 Set a list of directories from which it is safe to auto-load files.
1122 The delimiter (':' above) may differ according to the host platform.
1124 set debug auto-load on|off
1125 show debug auto-load
1126 Control display of debugging info for auto-loading the files above.
1128 set dprintf-style gdb|call|agent
1130 Control the way in which a dynamic printf is performed; "gdb"
1131 requests a GDB printf command, while "call" causes dprintf to call a
1132 function in the inferior. "agent" requests that the target agent
1133 (such as GDBserver) do the printing.
1135 set dprintf-function <expr>
1136 show dprintf-function
1137 set dprintf-channel <expr>
1138 show dprintf-channel
1139 Set the function and optional first argument to the call when using
1140 the "call" style of dynamic printf.
1142 set disconnected-dprintf on|off
1143 show disconnected-dprintf
1144 Control whether agent-style dynamic printfs continue to be in effect
1145 after GDB disconnects.
1147 * New configure options
1149 --with-auto-load-dir
1150 Configure default value for the 'set auto-load scripts-directory'
1151 setting above. It defaults to '$debugdir:$datadir/auto-load',
1152 $debugdir representing global debugging info directories (available
1153 via 'show debug-file-directory') and $datadir representing GDB's data
1154 directory (available via 'show data-directory').
1156 --with-auto-load-safe-path
1157 Configure default value for the 'set auto-load safe-path' setting
1158 above. It defaults to the --with-auto-load-dir setting.
1160 --without-auto-load-safe-path
1161 Set 'set auto-load safe-path' to '/', effectively disabling this
1164 * New remote packets
1166 z0/z1 conditional breakpoints extension
1168 The z0/z1 breakpoint insertion packets have been extended to carry
1169 a list of conditional expressions over to the remote stub depending on the
1170 condition evaluation mode. The use of this extension can be controlled
1171 via the "set remote conditional-breakpoints-packet" command.
1175 Specify the signals which the remote stub may pass to the debugged
1176 program without GDB involvement.
1178 * New command line options
1180 --init-command=FILE, -ix Like --command, -x but execute it
1181 before loading inferior.
1182 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1183 execute it before loading inferior.
1185 *** Changes in GDB 7.4
1187 * GDB now handles ambiguous linespecs more consistently; the existing
1188 FILE:LINE support has been expanded to other types of linespecs. A
1189 breakpoint will now be set on all matching locations in all
1190 inferiors, and locations will be added or removed according to
1193 * GDB now allows you to skip uninteresting functions and files when
1194 stepping with the "skip function" and "skip file" commands.
1196 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1197 and "show remote hardware-watchpoint-length-limit". These allows to
1198 set or show the maximum length limit (in bytes) of a remote
1199 target hardware watchpoint.
1201 This allows e.g. to use "unlimited" hardware watchpoints with the
1202 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1203 watchpoints are slower than real hardware watchpoints but are
1204 significantly faster than gdb software watchpoints.
1208 ** The register_pretty_printer function in module gdb.printing now takes
1209 an optional `replace' argument. If True, the new printer replaces any
1212 ** The "maint set python print-stack on|off" command has been
1213 deprecated and will be deleted in GDB 7.5.
1214 A new command: "set python print-stack none|full|message" has
1215 replaced it. Additionally, the default for "print-stack" is
1216 now "message", which just prints the error message without
1219 ** A prompt substitution hook (prompt_hook) is now available to the
1222 ** A new Python module, gdb.prompt has been added to the GDB Python
1223 modules library. This module provides functionality for
1224 escape sequences in prompts (used by set/show
1225 extended-prompt). These escape sequences are replaced by their
1226 corresponding value.
1228 ** Python commands and convenience-functions located in
1229 'data-directory'/python/gdb/command and
1230 'data-directory'/python/gdb/function are now automatically loaded
1233 ** Blocks now provide four new attributes. global_block and
1234 static_block will return the global and static blocks
1235 respectively. is_static and is_global are boolean attributes
1236 that indicate if the block is one of those two types.
1238 ** Symbols now provide the "type" attribute, the type of the symbol.
1240 ** The "gdb.breakpoint" function has been deprecated in favor of
1243 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1244 of a function. This class is based on the "finish" command
1245 available in the CLI.
1247 ** Type objects for struct and union types now allow access to
1248 the fields using standard Python dictionary (mapping) methods.
1249 For example, "some_type['myfield']" now works, as does
1250 "some_type.items()".
1252 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1255 ** A new function, "deep_items" has been added to the gdb.types
1256 module in the GDB Python modules library. This function returns
1257 an iterator over the fields of a struct or union type. Unlike
1258 the standard Python "iteritems" method, it will recursively traverse
1259 any anonymous fields.
1263 ** "*stopped" events can report several new "reason"s, such as
1266 ** Breakpoint changes are now notified using new async records, like
1267 "=breakpoint-modified".
1269 ** New command -ada-task-info.
1271 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1272 $sdir specifies the default system locations of shared libraries.
1273 $pdir specifies the directory where the libpthread used by the application
1276 GDB no longer looks in $sdir and $pdir after it has searched the directories
1277 mentioned in libthread-db-search-path. If you want to search those
1278 directories, they must be specified in libthread-db-search-path.
1279 The default value of libthread-db-search-path on GNU/Linux and Solaris
1280 systems is now "$sdir:$pdir".
1282 $pdir is not supported by gdbserver, it is currently ignored.
1283 $sdir is supported by gdbserver.
1285 * New configure option --with-iconv-bin.
1286 When using the internationalization support like the one in the GNU C
1287 library, GDB will invoke the "iconv" program to get a list of supported
1288 character sets. If this program lives in a non-standard location, one can
1289 use this option to specify where to find it.
1291 * When natively debugging programs on PowerPC BookE processors running
1292 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1293 watchpoints, which specify a mask in addition to an address to watch.
1294 The mask specifies that some bits of an address (the bits which are
1295 reset in the mask) should be ignored when matching the address accessed
1296 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1297 section in the user manual for more details.
1299 * The new option --once causes GDBserver to stop listening for connections once
1300 the first connection is made. The listening port used by GDBserver will
1301 become available after that.
1303 * New commands "info macros" and "alias" have been added.
1305 * New function parameters suffix @entry specifies value of function parameter
1306 at the time the function got called. Entry values are available only since
1312 "!" is now an alias of the "shell" command.
1313 Note that no space is needed between "!" and SHELL COMMAND.
1317 watch EXPRESSION mask MASK_VALUE
1318 The watch command now supports the mask argument which allows creation
1319 of masked watchpoints, if the current architecture supports this feature.
1321 info auto-load-scripts [REGEXP]
1322 This command was formerly named "maintenance print section-scripts".
1323 It is now generally useful and is no longer a maintenance-only command.
1325 info macro [-all] [--] MACRO
1326 The info macro command has new options `-all' and `--'. The first for
1327 printing all definitions of a macro. The second for explicitly specifying
1328 the end of arguments and the beginning of the macro name in case the macro
1329 name starts with a hyphen.
1331 collect[/s] EXPRESSIONS
1332 The tracepoint collect command now takes an optional modifier "/s"
1333 that directs it to dereference pointer-to-character types and
1334 collect the bytes of memory up to a zero byte. The behavior is
1335 similar to what you see when you use the regular print command on a
1336 string. An optional integer following the "/s" sets a bound on the
1337 number of bytes that will be collected.
1340 The trace start command now interprets any supplied arguments as a
1341 note to be recorded with the trace run, with an effect similar to
1342 setting the variable trace-notes.
1345 The trace stop command now interprets any arguments as a note to be
1346 mentioned along with the tstatus report that the trace was stopped
1347 with a command. The effect is similar to setting the variable
1350 * Tracepoints can now be enabled and disabled at any time after a trace
1351 experiment has been started using the standard "enable" and "disable"
1352 commands. It is now possible to start a trace experiment with no enabled
1353 tracepoints; GDB will display a warning, but will allow the experiment to
1354 begin, assuming that tracepoints will be enabled as needed while the trace
1357 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1358 locations with 4-byte instructions, when they were previously
1359 limited to locations with instructions of 5 bytes or longer.
1363 set debug dwarf2-read
1364 show debug dwarf2-read
1365 Turns on or off display of debugging messages related to reading
1366 DWARF debug info. The default is off.
1368 set debug symtab-create
1369 show debug symtab-create
1370 Turns on or off display of debugging messages related to symbol table
1371 creation. The default is off.
1374 show extended-prompt
1375 Set the GDB prompt, and allow escape sequences to be inserted to
1376 display miscellaneous information (see 'help set extended-prompt'
1377 for the list of sequences). This prompt (and any information
1378 accessed through the escape sequences) is updated every time the
1379 prompt is displayed.
1381 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1382 show print entry-values
1383 Set printing of frame argument values at function entry. In some cases
1384 GDB can determine the value of function argument which was passed by the
1385 function caller, even if the value was modified inside the called function.
1387 set debug entry-values
1388 show debug entry-values
1389 Control display of debugging info for determining frame argument values at
1390 function entry and virtual tail call frames.
1392 set basenames-may-differ
1393 show basenames-may-differ
1394 Set whether a source file may have multiple base names.
1395 (A "base name" is the name of a file with the directory part removed.
1396 Example: The base name of "/home/user/hello.c" is "hello.c".)
1397 If set, GDB will canonicalize file names (e.g., expand symlinks)
1398 before comparing them. Canonicalization is an expensive operation,
1399 but it allows the same file be known by more than one base name.
1400 If not set (the default), all source files are assumed to have just
1401 one base name, and gdb will do file name comparisons more efficiently.
1407 Set a user name and notes for the current and any future trace runs.
1408 This is useful for long-running and/or disconnected traces, to
1409 inform others (or yourself) as to who is running the trace, supply
1410 contact information, or otherwise explain what is going on.
1412 set trace-stop-notes
1413 show trace-stop-notes
1414 Set a note attached to the trace run, that is displayed when the
1415 trace has been stopped by a tstop command. This is useful for
1416 instance as an explanation, if you are stopping a trace run that was
1417 started by someone else.
1419 * New remote packets
1423 Dynamically enable a tracepoint in a started trace experiment.
1427 Dynamically disable a tracepoint in a started trace experiment.
1431 Set the user and notes of the trace run.
1435 Query the current status of a tracepoint.
1439 Query the minimum length of instruction at which a fast tracepoint may
1442 * Dcache size (number of lines) and line-size are now runtime-configurable
1443 via "set dcache line" and "set dcache line-size" commands.
1447 Texas Instruments TMS320C6x tic6x-*-*
1451 Renesas RL78 rl78-*-elf
1453 *** Changes in GDB 7.3.1
1455 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1457 *** Changes in GDB 7.3
1459 * GDB has a new command: "thread find [REGEXP]".
1460 It finds the thread id whose name, target id, or thread extra info
1461 matches the given regular expression.
1463 * The "catch syscall" command now works on mips*-linux* targets.
1465 * The -data-disassemble MI command now supports modes 2 and 3 for
1466 dumping the instruction opcodes.
1468 * New command line options
1470 -data-directory DIR Specify DIR as the "data-directory".
1471 This is mostly for testing purposes.
1473 * The "maint set python auto-load on|off" command has been renamed to
1474 "set auto-load-scripts on|off".
1476 * GDB has a new command: "set directories".
1477 It is like the "dir" command except that it replaces the
1478 source path list instead of augmenting it.
1480 * GDB now understands thread names.
1482 On GNU/Linux, "info threads" will display the thread name as set by
1483 prctl or pthread_setname_np.
1485 There is also a new command, "thread name", which can be used to
1486 assign a name internally for GDB to display.
1489 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1490 has been integrated into GDB.
1494 ** The function gdb.Write now accepts an optional keyword 'stream'.
1495 This keyword, when provided, will direct the output to either
1496 stdout, stderr, or GDB's logging output.
1498 ** Parameters can now be be sub-classed in Python, and in particular
1499 you may implement the get_set_doc and get_show_doc functions.
1500 This improves how Parameter set/show documentation is processed
1501 and allows for more dynamic content.
1503 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1504 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1505 have an is_valid method.
1507 ** Breakpoints can now be sub-classed in Python, and in particular
1508 you may implement a 'stop' function that is executed each time
1509 the inferior reaches that breakpoint.
1511 ** New function gdb.lookup_global_symbol looks up a global symbol.
1513 ** GDB values in Python are now callable if the value represents a
1514 function. For example, if 'some_value' represents a function that
1515 takes two integer parameters and returns a value, you can call
1516 that function like so:
1518 result = some_value (10,20)
1520 ** Module gdb.types has been added.
1521 It contains a collection of utilities for working with gdb.Types objects:
1522 get_basic_type, has_field, make_enum_dict.
1524 ** Module gdb.printing has been added.
1525 It contains utilities for writing and registering pretty-printers.
1526 New classes: PrettyPrinter, SubPrettyPrinter,
1527 RegexpCollectionPrettyPrinter.
1528 New function: register_pretty_printer.
1530 ** New commands "info pretty-printers", "enable pretty-printer" and
1531 "disable pretty-printer" have been added.
1533 ** gdb.parameter("directories") is now available.
1535 ** New function gdb.newest_frame returns the newest frame in the
1538 ** The gdb.InferiorThread class has a new "name" attribute. This
1539 holds the thread's name.
1541 ** Python Support for Inferior events.
1542 Python scripts can add observers to be notified of events
1543 occurring in the process being debugged.
1544 The following events are currently supported:
1545 - gdb.events.cont Continue event.
1546 - gdb.events.exited Inferior exited event.
1547 - gdb.events.stop Signal received, and Breakpoint hit events.
1551 ** GDB now puts template parameters in scope when debugging in an
1552 instantiation. For example, if you have:
1554 template<int X> int func (void) { return X; }
1556 then if you step into func<5>, "print X" will show "5". This
1557 feature requires proper debuginfo support from the compiler; it
1558 was added to GCC 4.5.
1560 ** The motion commands "next", "finish", "until", and "advance" now
1561 work better when exceptions are thrown. In particular, GDB will
1562 no longer lose control of the inferior; instead, the GDB will
1563 stop the inferior at the point at which the exception is caught.
1564 This functionality requires a change in the exception handling
1565 code that was introduced in GCC 4.5.
1567 * GDB now follows GCC's rules on accessing volatile objects when
1568 reading or writing target state during expression evaluation.
1569 One notable difference to prior behavior is that "print x = 0"
1570 no longer generates a read of x; the value of the assignment is
1571 now always taken directly from the value being assigned.
1573 * GDB now has some support for using labels in the program's source in
1574 linespecs. For instance, you can use "advance label" to continue
1575 execution to a label.
1577 * GDB now has support for reading and writing a new .gdb_index
1578 section. This section holds a fast index of DWARF debugging
1579 information and can be used to greatly speed up GDB startup and
1580 operation. See the documentation for `save gdb-index' for details.
1582 * The "watch" command now accepts an optional "-location" argument.
1583 When used, this causes GDB to watch the memory referred to by the
1584 expression. Such a watchpoint is never deleted due to it going out
1587 * GDB now supports thread debugging of core dumps on GNU/Linux.
1589 GDB now activates thread debugging using the libthread_db library
1590 when debugging GNU/Linux core dumps, similarly to when debugging
1591 live processes. As a result, when debugging a core dump file, GDB
1592 is now able to display pthread_t ids of threads. For example, "info
1593 threads" shows the same output as when debugging the process when it
1594 was live. In earlier releases, you'd see something like this:
1597 * 1 LWP 6780 main () at main.c:10
1599 While now you see this:
1602 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1604 It is also now possible to inspect TLS variables when debugging core
1607 When debugging a core dump generated on a machine other than the one
1608 used to run GDB, you may need to point GDB at the correct
1609 libthread_db library with the "set libthread-db-search-path"
1610 command. See the user manual for more details on this command.
1612 * When natively debugging programs on PowerPC BookE processors running
1613 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1614 which stop execution of the inferior whenever it executes an instruction
1615 at any address within the specified range. See the "PowerPC Embedded"
1616 section in the user manual for more details.
1618 * New features in the GDB remote stub, GDBserver
1620 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1621 and i686 LynxOS (version 5.x).
1623 ** GDBserver is now supported on Blackfin Linux.
1625 * New native configurations
1627 ia64 HP-UX ia64-*-hpux*
1631 Analog Devices, Inc. Blackfin Processor bfin-*
1633 * Ada task switching is now supported on sparc-elf targets when
1634 debugging a program using the Ravenscar Profile. For more information,
1635 see the "Tasking Support when using the Ravenscar Profile" section
1636 in the GDB user manual.
1638 * Guile support was removed.
1640 * New features in the GNU simulator
1642 ** The --map-info flag lists all known core mappings.
1644 ** CFI flashes may be simulated via the "cfi" device.
1646 *** Changes in GDB 7.2
1648 * Shared library support for remote targets by default
1650 When GDB is configured for a generic, non-OS specific target, like
1651 for example, --target=arm-eabi or one of the many *-*-elf targets,
1652 GDB now queries remote stubs for loaded shared libraries using the
1653 `qXfer:libraries:read' packet. Previously, shared library support
1654 was always disabled for such configurations.
1658 ** Argument Dependent Lookup (ADL)
1660 In C++ ADL lookup directs function search to the namespaces of its
1661 arguments even if the namespace has not been imported.
1671 Here the compiler will search for `foo' in the namespace of 'b'
1672 and find A::foo. GDB now supports this. This construct is commonly
1673 used in the Standard Template Library for operators.
1675 ** Improved User Defined Operator Support
1677 In addition to member operators, GDB now supports lookup of operators
1678 defined in a namespace and imported with a `using' directive, operators
1679 defined in the global scope, operators imported implicitly from an
1680 anonymous namespace, and the ADL operators mentioned in the previous
1682 GDB now also supports proper overload resolution for all the previously
1683 mentioned flavors of operators.
1685 ** static const class members
1687 Printing of static const class members that are initialized in the
1688 class definition has been fixed.
1690 * Windows Thread Information Block access.
1692 On Windows targets, GDB now supports displaying the Windows Thread
1693 Information Block (TIB) structure. This structure is visible either
1694 by using the new command `info w32 thread-information-block' or, by
1695 dereferencing the new convenience variable named `$_tlb', a
1696 thread-specific pointer to the TIB. This feature is also supported
1697 when remote debugging using GDBserver.
1699 * Static tracepoints
1701 Static tracepoints are calls in the user program into a tracing
1702 library. One such library is a port of the LTTng kernel tracer to
1703 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1704 When debugging with GDBserver, GDB now supports combining the GDB
1705 tracepoint machinery with such libraries. For example: the user can
1706 use GDB to probe a static tracepoint marker (a call from the user
1707 program into the tracing library) with the new "strace" command (see
1708 "New commands" below). This creates a "static tracepoint" in the
1709 breakpoint list, that can be manipulated with the same feature set
1710 as fast and regular tracepoints. E.g., collect registers, local and
1711 global variables, collect trace state variables, and define
1712 tracepoint conditions. In addition, the user can collect extra
1713 static tracepoint marker specific data, by collecting the new
1714 $_sdata internal variable. When analyzing the trace buffer, you can
1715 inspect $_sdata like any other variable available to GDB. For more
1716 information, see the "Tracepoints" chapter in GDB user manual. New
1717 remote packets have been defined to support static tracepoints, see
1718 the "New remote packets" section below.
1720 * Better reconstruction of tracepoints after disconnected tracing
1722 GDB will attempt to download the original source form of tracepoint
1723 definitions when starting a trace run, and then will upload these
1724 upon reconnection to the target, resulting in a more accurate
1725 reconstruction of the tracepoints that are in use on the target.
1729 You can now exercise direct control over the ways that GDB can
1730 affect your program. For instance, you can disallow the setting of
1731 breakpoints, so that the program can run continuously (assuming
1732 non-stop mode). In addition, the "observer" variable is available
1733 to switch all of the different controls; in observer mode, GDB
1734 cannot affect the target's behavior at all, which is useful for
1735 tasks like diagnosing live systems in the field.
1737 * The new convenience variable $_thread holds the number of the
1740 * New remote packets
1744 Return the address of the Windows Thread Information Block of a given thread.
1748 In response to several of the tracepoint packets, the target may now
1749 also respond with a number of intermediate `qRelocInsn' request
1750 packets before the final result packet, to have GDB handle
1751 relocating an instruction to execute at a different address. This
1752 is particularly useful for stubs that support fast tracepoints. GDB
1753 reports support for this feature in the qSupported packet.
1757 List static tracepoint markers in the target program.
1761 List static tracepoint markers at a given address in the target
1764 qXfer:statictrace:read
1766 Read the static trace data collected (by a `collect $_sdata'
1767 tracepoint action). The remote stub reports support for this packet
1768 to gdb's qSupported query.
1772 Send the current settings of GDB's permission flags.
1776 Send part of the source (textual) form of a tracepoint definition,
1777 which includes location, conditional, and action list.
1779 * The source command now accepts a -s option to force searching for the
1780 script in the source search path even if the script name specifies
1783 * New features in the GDB remote stub, GDBserver
1785 - GDBserver now support tracepoints (including fast tracepoints, and
1786 static tracepoints). The feature is currently supported by the
1787 i386-linux and amd64-linux builds. See the "Tracepoints support
1788 in gdbserver" section in the manual for more information.
1790 GDBserver JIT compiles the tracepoint's conditional agent
1791 expression bytecode into native code whenever possible for low
1792 overhead dynamic tracepoints conditionals. For such tracepoints,
1793 an expression that examines program state is evaluated when the
1794 tracepoint is reached, in order to determine whether to capture
1795 trace data. If the condition is simple and false, processing the
1796 tracepoint finishes very quickly and no data is gathered.
1798 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1799 for static tracepoints support.
1801 - GDBserver now supports x86_64 Windows 64-bit debugging.
1803 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1804 it understands register description.
1806 * The --batch flag now disables pagination and queries.
1808 * X86 general purpose registers
1810 GDB now supports reading/writing byte, word and double-word x86
1811 general purpose registers directly. This means you can use, say,
1812 $ah or $ax to refer, respectively, to the byte register AH and
1813 16-bit word register AX that are actually portions of the 32-bit
1814 register EAX or 64-bit register RAX.
1816 * The `commands' command now accepts a range of breakpoints to modify.
1817 A plain `commands' following a command that creates multiple
1818 breakpoints affects all the breakpoints set by that command. This
1819 applies to breakpoints set by `rbreak', and also applies when a
1820 single `break' command creates multiple breakpoints (e.g.,
1821 breakpoints on overloaded c++ functions).
1823 * The `rbreak' command now accepts a filename specification as part of
1824 its argument, limiting the functions selected by the regex to those
1825 in the specified file.
1827 * Support for remote debugging Windows and SymbianOS shared libraries
1828 from Unix hosts has been improved. Non Windows GDB builds now can
1829 understand target reported file names that follow MS-DOS based file
1830 system semantics, such as file names that include drive letters and
1831 use the backslash character as directory separator. This makes it
1832 possible to transparently use the "set sysroot" and "set
1833 solib-search-path" on Unix hosts to point as host copies of the
1834 target's shared libraries. See the new command "set
1835 target-file-system-kind" described below, and the "Commands to
1836 specify files" section in the user manual for more information.
1840 eval template, expressions...
1841 Convert the values of one or more expressions under the control
1842 of the string template to a command line, and call it.
1844 set target-file-system-kind unix|dos-based|auto
1845 show target-file-system-kind
1846 Set or show the assumed file system kind for target reported file
1849 save breakpoints <filename>
1850 Save all current breakpoint definitions to a file suitable for use
1851 in a later debugging session. To read the saved breakpoint
1852 definitions, use the `source' command.
1854 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1857 info static-tracepoint-markers
1858 Display information about static tracepoint markers in the target.
1860 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1861 Define a static tracepoint by probing a marker at the given
1862 function, line, address, or marker ID.
1866 Enable and disable observer mode.
1868 set may-write-registers on|off
1869 set may-write-memory on|off
1870 set may-insert-breakpoints on|off
1871 set may-insert-tracepoints on|off
1872 set may-insert-fast-tracepoints on|off
1873 set may-interrupt on|off
1874 Set individual permissions for GDB effects on the target. Note that
1875 some of these settings can have undesirable or surprising
1876 consequences, particularly when changed in the middle of a session.
1877 For instance, disabling the writing of memory can prevent
1878 breakpoints from being inserted, cause single-stepping to fail, or
1879 even crash your program, if you disable after breakpoints have been
1880 inserted. However, GDB should not crash.
1882 set record memory-query on|off
1883 show record memory-query
1884 Control whether to stop the inferior if memory changes caused
1885 by an instruction cannot be recorded.
1890 The disassemble command now supports "start,+length" form of two arguments.
1894 ** GDB now provides a new directory location, called the python directory,
1895 where Python scripts written for GDB can be installed. The location
1896 of that directory is <data-directory>/python, where <data-directory>
1897 is the GDB data directory. For more details, see section `Scripting
1898 GDB using Python' in the manual.
1900 ** The GDB Python API now has access to breakpoints, symbols, symbol
1901 tables, program spaces, inferiors, threads and frame's code blocks.
1902 Additionally, GDB Parameters can now be created from the API, and
1903 manipulated via set/show in the CLI.
1905 ** New functions gdb.target_charset, gdb.target_wide_charset,
1906 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1908 ** New exception gdb.GdbError.
1910 ** Pretty-printers are now also looked up in the current program space.
1912 ** Pretty-printers can now be individually enabled and disabled.
1914 ** GDB now looks for names of Python scripts to auto-load in a
1915 special section named `.debug_gdb_scripts', in addition to looking
1916 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1918 * Tracepoint actions were unified with breakpoint commands. In particular,
1919 there are no longer differences in "info break" output for breakpoints and
1920 tracepoints and the "commands" command can be used for both tracepoints and
1921 regular breakpoints.
1925 ARM Symbian arm*-*-symbianelf*
1927 * D language support.
1928 GDB now supports debugging programs written in the D programming
1931 * GDB now supports the extended ptrace interface for PowerPC which is
1932 available since Linux kernel version 2.6.34. This automatically enables
1933 any hardware breakpoints and additional hardware watchpoints available in
1934 the processor. The old ptrace interface exposes just one hardware
1935 watchpoint and no hardware breakpoints.
1937 * GDB is now able to use the Data Value Compare (DVC) register available on
1938 embedded PowerPC processors to implement in hardware simple watchpoint
1939 conditions of the form:
1941 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1943 This works in native GDB running on Linux kernels with the extended ptrace
1944 interface mentioned above.
1946 *** Changes in GDB 7.1
1950 ** Namespace Support
1952 GDB now supports importing of namespaces in C++. This enables the
1953 user to inspect variables from imported namespaces. Support for
1954 namepace aliasing has also been added. So, if a namespace is
1955 aliased in the current scope (e.g. namepace C=A; ) the user can
1956 print variables using the alias (e.g. (gdb) print C::x).
1960 All known bugs relating to the printing of virtual base class were
1961 fixed. It is now possible to call overloaded static methods using a
1966 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1967 and reinterpret_cast<> are now handled by the C++ expression parser.
1971 Xilinx MicroBlaze microblaze-*-*
1976 Xilinx MicroBlaze microblaze
1979 * Multi-program debugging.
1981 GDB now has support for multi-program (a.k.a. multi-executable or
1982 multi-exec) debugging. This allows for debugging multiple inferiors
1983 simultaneously each running a different program under the same GDB
1984 session. See "Debugging Multiple Inferiors and Programs" in the
1985 manual for more information. This implied some user visible changes
1986 in the multi-inferior support. For example, "info inferiors" now
1987 lists inferiors that are not running yet or that have exited
1988 already. See also "New commands" and "New options" below.
1990 * New tracing features
1992 GDB's tracepoint facility now includes several new features:
1994 ** Trace state variables
1996 GDB tracepoints now include support for trace state variables, which
1997 are variables managed by the target agent during a tracing
1998 experiment. They are useful for tracepoints that trigger each
1999 other, so for instance one tracepoint can count hits in a variable,
2000 and then a second tracepoint has a condition that is true when the
2001 count reaches a particular value. Trace state variables share the
2002 $-syntax of GDB convenience variables, and can appear in both
2003 tracepoint actions and condition expressions. Use the "tvariable"
2004 command to create, and "info tvariables" to view; see "Trace State
2005 Variables" in the manual for more detail.
2009 GDB now includes an option for defining fast tracepoints, which
2010 targets may implement more efficiently, such as by installing a jump
2011 into the target agent rather than a trap instruction. The resulting
2012 speedup can be by two orders of magnitude or more, although the
2013 tradeoff is that some program locations on some target architectures
2014 might not allow fast tracepoint installation, for instance if the
2015 instruction to be replaced is shorter than the jump. To request a
2016 fast tracepoint, use the "ftrace" command, with syntax identical to
2017 the regular trace command.
2019 ** Disconnected tracing
2021 It is now possible to detach GDB from the target while it is running
2022 a trace experiment, then reconnect later to see how the experiment
2023 is going. In addition, a new variable disconnected-tracing lets you
2024 tell the target agent whether to continue running a trace if the
2025 connection is lost unexpectedly.
2029 GDB now has the ability to save the trace buffer into a file, and
2030 then use that file as a target, similarly to you can do with
2031 corefiles. You can select trace frames, print data that was
2032 collected in them, and use tstatus to display the state of the
2033 tracing run at the moment that it was saved. To create a trace
2034 file, use "tsave <filename>", and to use it, do "target tfile
2037 ** Circular trace buffer
2039 You can ask the target agent to handle the trace buffer as a
2040 circular buffer, discarding the oldest trace frames to make room for
2041 newer ones, by setting circular-trace-buffer to on. This feature may
2042 not be available for all target agents.
2047 The disassemble command, when invoked with two arguments, now requires
2048 the arguments to be comma-separated.
2051 The info variables command now displays variable definitions. Files
2052 which only declare a variable are not shown.
2055 The source command is now capable of sourcing Python scripts.
2056 This feature is dependent on the debugger being build with Python
2059 Related to this enhancement is also the introduction of a new command
2060 "set script-extension" (see below).
2062 * New commands (for set/show, see "New options" below)
2064 record save [<FILENAME>]
2065 Save a file (in core file format) containing the process record
2066 execution log for replay debugging at a later time.
2068 record restore <FILENAME>
2069 Restore the process record execution log that was saved at an
2070 earlier time, for replay debugging.
2072 add-inferior [-copies <N>] [-exec <FILENAME>]
2075 clone-inferior [-copies <N>] [ID]
2076 Make a new inferior ready to execute the same program another
2077 inferior has loaded.
2082 maint info program-spaces
2083 List the program spaces loaded into GDB.
2085 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2086 show remote interrupt-sequence
2087 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2088 as the sequence to the remote target in order to interrupt the execution.
2089 Ctrl-C is a default. Some system prefers BREAK which is high level of
2090 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2091 Magic SysRq g. It is BREAK signal and character 'g'.
2093 set remote interrupt-on-connect [on | off]
2094 show remote interrupt-on-connect
2095 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2096 remote target when gdb connects to it. This is needed when you debug
2099 set remotebreak [on | off]
2101 Deprecated. Use "set/show remote interrupt-sequence" instead.
2103 tvariable $NAME [ = EXP ]
2104 Create or modify a trace state variable.
2107 List trace state variables and their values.
2109 delete tvariable $NAME ...
2110 Delete one or more trace state variables.
2113 Evaluate the given expressions without collecting anything into the
2114 trace buffer. (Valid in tracepoint actions only.)
2116 ftrace FN / FILE:LINE / *ADDR
2117 Define a fast tracepoint at the given function, line, or address.
2119 * New expression syntax
2121 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2122 GDB now parses 0b101010 identically with 42.
2126 set follow-exec-mode new|same
2127 show follow-exec-mode
2128 Control whether GDB reuses the same inferior across an exec call or
2129 creates a new one. This is useful to be able to restart the old
2130 executable after the inferior having done an exec call.
2132 set default-collect EXPR, ...
2133 show default-collect
2134 Define a list of expressions to be collected at each tracepoint.
2135 This is a useful way to ensure essential items are not overlooked,
2136 such as registers or a critical global variable.
2138 set disconnected-tracing
2139 show disconnected-tracing
2140 If set to 1, the target is instructed to continue tracing if it
2141 loses its connection to GDB. If 0, the target is to stop tracing
2144 set circular-trace-buffer
2145 show circular-trace-buffer
2146 If set to on, the target is instructed to use a circular trace buffer
2147 and discard the oldest trace frames instead of stopping the trace due
2148 to a full trace buffer. If set to off, the trace stops when the buffer
2149 fills up. Some targets may not support this.
2151 set script-extension off|soft|strict
2152 show script-extension
2153 If set to "off", the debugger does not perform any script language
2154 recognition, and all sourced files are assumed to be GDB scripts.
2155 If set to "soft" (the default), files are sourced according to
2156 filename extension, falling back to GDB scripts if the first
2158 If set to "strict", files are sourced according to filename extension.
2160 set ada trust-PAD-over-XVS on|off
2161 show ada trust-PAD-over-XVS
2162 If off, activate a workaround against a bug in the debugging information
2163 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2164 the GCC sources for more information about the GNAT encoding and
2165 PAD types in particular). It is always safe to set this option to
2166 off, but this introduces a slight performance penalty. The default
2169 * Python API Improvements
2171 ** GDB provides the new class gdb.LazyString. This is useful in
2172 some pretty-printing cases. The new method gdb.Value.lazy_string
2173 provides a simple way to create objects of this type.
2175 ** The fields returned by gdb.Type.fields now have an
2176 `is_base_class' attribute.
2178 ** The new method gdb.Type.range returns the range of an array type.
2180 ** The new method gdb.parse_and_eval can be used to parse and
2181 evaluate an expression.
2183 * New remote packets
2186 Define a trace state variable.
2189 Get the current value of a trace state variable.
2192 Set desired tracing behavior upon disconnection.
2195 Set the trace buffer to be linear or circular.
2198 Get data about the tracepoints currently in use.
2202 Process record now works correctly with hardware watchpoints.
2204 Multiple bug fixes have been made to the mips-irix port, making it
2205 much more reliable. In particular:
2206 - Debugging threaded applications is now possible again. Previously,
2207 GDB would hang while starting the program, or while waiting for
2208 the program to stop at a breakpoint.
2209 - Attaching to a running process no longer hangs.
2210 - An error occurring while loading a core file has been fixed.
2211 - Changing the value of the PC register now works again. This fixes
2212 problems observed when using the "jump" command, or when calling
2213 a function from GDB, or even when assigning a new value to $pc.
2214 - With the "finish" and "return" commands, the return value for functions
2215 returning a small array is now correctly printed.
2216 - It is now possible to break on shared library code which gets executed
2217 during a shared library init phase (code executed while executing
2218 their .init section). Previously, the breakpoint would have no effect.
2219 - GDB is now able to backtrace through the signal handler for
2220 non-threaded programs.
2222 PIE (Position Independent Executable) programs debugging is now supported.
2223 This includes debugging execution of PIC (Position Independent Code) shared
2224 libraries although for that, it should be possible to run such libraries as an
2227 *** Changes in GDB 7.0
2229 * GDB now has an interface for JIT compilation. Applications that
2230 dynamically generate code can create symbol files in memory and register
2231 them with GDB. For users, the feature should work transparently, and
2232 for JIT developers, the interface is documented in the GDB manual in the
2233 "JIT Compilation Interface" chapter.
2235 * Tracepoints may now be conditional. The syntax is as for
2236 breakpoints; either an "if" clause appended to the "trace" command,
2237 or the "condition" command is available. GDB sends the condition to
2238 the target for evaluation using the same bytecode format as is used
2239 for tracepoint actions.
2241 * The disassemble command now supports: an optional /r modifier, print the
2242 raw instructions in hex as well as in symbolic form, and an optional /m
2243 modifier to print mixed source+assembly.
2245 * Process record and replay
2247 In a architecture environment that supports ``process record and
2248 replay'', ``process record and replay'' target can record a log of
2249 the process execution, and replay it with both forward and reverse
2252 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2253 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2254 set execution-direction {forward|reverse}, for targets that support
2257 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2258 feature is available with a native GDB running on kernel version
2261 * GDB now has support for multi-byte and wide character sets on the
2262 target. Strings whose character type is wchar_t, char16_t, or
2263 char32_t are now correctly printed. GDB supports wide- and unicode-
2264 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2265 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2266 `printf'. This feature requires iconv to work properly; if your
2267 system does not have a working iconv, GDB can use GNU libiconv. See
2268 the installation instructions for more information.
2270 * GDB now supports automatic retrieval of shared library files from
2271 remote targets. To use this feature, specify a system root that begins
2272 with the `remote:' prefix, either via the `set sysroot' command or via
2273 the `--with-sysroot' configure-time option.
2275 * "info sharedlibrary" now takes an optional regex of libraries to show,
2276 and it now reports if a shared library has no debugging information.
2278 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2279 now complete on file names.
2281 * When completing in expressions, gdb will attempt to limit
2282 completions to allowable structure or union fields, where appropriate.
2283 For instance, consider:
2285 # struct example { int f1; double f2; };
2286 # struct example variable;
2289 If the user types TAB at the end of this command line, the available
2290 completions will be "f1" and "f2".
2292 * Inlined functions are now supported. They show up in backtraces, and
2293 the "step", "next", and "finish" commands handle them automatically.
2295 * GDB now supports the token-splicing (##) and stringification (#)
2296 operators when expanding macros. It also supports variable-arity
2299 * GDB now supports inspecting extra signal information, exported by
2300 the new $_siginfo convenience variable. The feature is currently
2301 implemented on linux ARM, i386 and amd64.
2303 * GDB can now display the VFP floating point registers and NEON vector
2304 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2305 can provide these registers (requires Linux 2.6.30 or later). Remote
2306 and simulator targets may also provide them.
2308 * New remote packets
2311 Search memory for a sequence of bytes.
2314 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2315 operation over reliable transport links. Use of this packet is
2316 controlled by the `set remote noack-packet' command.
2319 Kill the process with the specified process ID. Use this in preference
2320 to `k' when multiprocess protocol extensions are supported.
2323 Obtains additional operating system information
2327 Read or write additional signal information.
2329 * Removed remote protocol undocumented extension
2331 An undocumented extension to the remote protocol's `S' stop reply
2332 packet that permited the stub to pass a process id was removed.
2333 Remote servers should use the `T' stop reply packet instead.
2335 * GDB now supports multiple function calling conventions according to the
2336 DWARF-2 DW_AT_calling_convention function attribute.
2338 * The SH target utilizes the aforementioned change to distinguish between gcc
2339 and Renesas calling convention. It also adds the new CLI commands
2340 `set/show sh calling-convention'.
2342 * GDB can now read compressed debug sections, as produced by GNU gold
2343 with the --compress-debug-sections=zlib flag.
2345 * 64-bit core files are now supported on AIX.
2347 * Thread switching is now supported on Tru64.
2349 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2350 which will be allocated using malloc later in program execution.
2352 * The qXfer:libraries:read remote procotol packet now allows passing a
2353 list of section offsets.
2355 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2356 conditions handling signals delivered during attach or thread creation
2357 have also been fixed.
2359 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2360 From the user's standpoint, all unqualified instances of True and False
2361 are treated as the standard definitions, regardless of context.
2363 * GDB now parses C++ symbol and type names more flexibly. For
2366 template<typename T> class C { };
2369 GDB will now correctly handle all of:
2371 ptype C<char const *>
2372 ptype C<char const*>
2373 ptype C<const char *>
2374 ptype C<const char*>
2376 * New features in the GDB remote stub, gdbserver
2378 - The "--wrapper" command-line argument tells gdbserver to use a
2379 wrapper program to launch programs for debugging.
2381 - On PowerPC and S/390 targets, it is now possible to use a single
2382 gdbserver executable to debug both 32-bit and 64-bit programs.
2383 (This requires gdbserver itself to be built as a 64-bit executable.)
2385 - gdbserver uses the new noack protocol mode for TCP connections to
2386 reduce communications latency, if also supported and enabled in GDB.
2388 - Support for the sparc64-linux-gnu target is now included in
2391 - The amd64-linux build of gdbserver now supports debugging both
2392 32-bit and 64-bit programs.
2394 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2395 now support hardware watchpoints, and will use them automatically
2400 GDB now has support for scripting using Python. Whether this is
2401 available is determined at configure time.
2403 New GDB commands can now be written in Python.
2405 * Ada tasking support
2407 Ada tasks can now be inspected in GDB. The following commands have
2411 Print the list of Ada tasks.
2413 Print detailed information about task number N.
2415 Print the task number of the current task.
2417 Switch the context of debugging to task number N.
2419 * Support for user-defined prefixed commands. The "define" command can
2420 add new commands to existing prefixes, e.g. "target".
2422 * Multi-inferior, multi-process debugging.
2424 GDB now has generalized support for multi-inferior debugging. See
2425 "Debugging Multiple Inferiors" in the manual for more information.
2426 Although availability still depends on target support, the command
2427 set is more uniform now. The GNU/Linux specific multi-forks support
2428 has been migrated to this new framework. This implied some user
2429 visible changes; see "New commands" and also "Removed commands"
2432 * Target descriptions can now describe the target OS ABI. See the
2433 "Target Description Format" section in the user manual for more
2436 * Target descriptions can now describe "compatible" architectures
2437 to indicate that the target can execute applications for a different
2438 architecture in addition to those for the main target architecture.
2439 See the "Target Description Format" section in the user manual for
2442 * Multi-architecture debugging.
2444 GDB now includes general supports for debugging applications on
2445 hybrid systems that use more than one single processor architecture
2446 at the same time. Each such hybrid architecture still requires
2447 specific support to be added. The only hybrid architecture supported
2448 in this version of GDB is the Cell Broadband Engine.
2450 * GDB now supports integrated debugging of Cell/B.E. applications that
2451 use both the PPU and SPU architectures. To enable support for hybrid
2452 Cell/B.E. debugging, you need to configure GDB to support both the
2453 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2454 --enable-targets configure option.
2456 * Non-stop mode debugging.
2458 For some targets, GDB now supports an optional mode of operation in
2459 which you can examine stopped threads while other threads continue
2460 to execute freely. This is referred to as non-stop mode, with the
2461 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2462 section in the user manual for more information.
2464 To be able to support remote non-stop debugging, a remote stub needs
2465 to implement the non-stop mode remote protocol extensions, as
2466 described in the "Remote Non-Stop" section of the user manual. The
2467 GDB remote stub, gdbserver, has been adjusted to support these
2468 extensions on linux targets.
2470 * New commands (for set/show, see "New options" below)
2472 catch syscall [NAME(S) | NUMBER(S)]
2473 Catch system calls. Arguments, which should be names of system
2474 calls or their numbers, mean catch only those syscalls. Without
2475 arguments, every syscall will be caught. When the inferior issues
2476 any of the specified syscalls, GDB will stop and announce the system
2477 call, both when it is called and when its call returns. This
2478 feature is currently available with a native GDB running on the
2479 Linux Kernel, under the following architectures: x86, x86_64,
2480 PowerPC and PowerPC64.
2482 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2484 Search memory for a sequence of bytes.
2486 maint set python print-stack
2487 maint show python print-stack
2488 Show a stack trace when an error is encountered in a Python script.
2491 Invoke CODE by passing it to the Python interpreter.
2496 These allow macros to be defined, undefined, and listed
2500 Show operating system information about processes.
2503 List the inferiors currently under GDB's control.
2506 Switch focus to inferior number NUM.
2509 Detach from inferior number NUM.
2512 Kill inferior number NUM.
2516 set spu stop-on-load
2517 show spu stop-on-load
2518 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2520 set spu auto-flush-cache
2521 show spu auto-flush-cache
2522 Control whether to automatically flush the software-managed cache
2523 during Cell/B.E. debugging.
2525 set sh calling-convention
2526 show sh calling-convention
2527 Control the calling convention used when calling SH target functions.
2530 show debug timestamp
2531 Control display of timestamps with GDB debugging output.
2533 set disassemble-next-line
2534 show disassemble-next-line
2535 Control display of disassembled source lines or instructions when
2538 set remote noack-packet
2539 show remote noack-packet
2540 Set/show the use of remote protocol QStartNoAckMode packet. See above
2541 under "New remote packets."
2543 set remote query-attached-packet
2544 show remote query-attached-packet
2545 Control use of remote protocol `qAttached' (query-attached) packet.
2547 set remote read-siginfo-object
2548 show remote read-siginfo-object
2549 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2552 set remote write-siginfo-object
2553 show remote write-siginfo-object
2554 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2557 set remote reverse-continue
2558 show remote reverse-continue
2559 Control use of remote protocol 'bc' (reverse-continue) packet.
2561 set remote reverse-step
2562 show remote reverse-step
2563 Control use of remote protocol 'bs' (reverse-step) packet.
2565 set displaced-stepping
2566 show displaced-stepping
2567 Control displaced stepping mode. Displaced stepping is a way to
2568 single-step over breakpoints without removing them from the debuggee.
2569 Also known as "out-of-line single-stepping".
2572 show debug displaced
2573 Control display of debugging info for displaced stepping.
2575 maint set internal-error
2576 maint show internal-error
2577 Control what GDB does when an internal error is detected.
2579 maint set internal-warning
2580 maint show internal-warning
2581 Control what GDB does when an internal warning is detected.
2586 Use a wrapper program to launch programs for debugging.
2588 set multiple-symbols (all|ask|cancel)
2589 show multiple-symbols
2590 The value of this variable can be changed to adjust the debugger behavior
2591 when an expression or a breakpoint location contains an ambiguous symbol
2592 name (an overloaded function name, for instance).
2594 set breakpoint always-inserted
2595 show breakpoint always-inserted
2596 Keep breakpoints always inserted in the target, as opposed to inserting
2597 them when resuming the target, and removing them when the target stops.
2598 This option can improve debugger performance on slow remote targets.
2600 set arm fallback-mode (arm|thumb|auto)
2601 show arm fallback-mode
2602 set arm force-mode (arm|thumb|auto)
2604 These commands control how ARM GDB determines whether instructions
2605 are ARM or Thumb. The default for both settings is auto, which uses
2606 the current CPSR value for instructions without symbols; previous
2607 versions of GDB behaved as if "set arm fallback-mode arm".
2609 set disable-randomization
2610 show disable-randomization
2611 Standalone programs run with the virtual address space randomization enabled
2612 by default on some platforms. This option keeps the addresses stable across
2613 multiple debugging sessions.
2617 Control whether other threads are stopped or not when some thread hits
2622 Requests that asynchronous execution is enabled in the target, if available.
2623 In this case, it's possible to resume target in the background, and interact
2624 with GDB while the target is running. "show target-async" displays the
2625 current state of asynchronous execution of the target.
2627 set target-wide-charset
2628 show target-wide-charset
2629 The target-wide-charset is the name of the character set that GDB
2630 uses when printing characters whose type is wchar_t.
2632 set tcp auto-retry (on|off)
2634 set tcp connect-timeout
2635 show tcp connect-timeout
2636 These commands allow GDB to retry failed TCP connections to a remote stub
2637 with a specified timeout period; this is useful if the stub is launched
2638 in parallel with GDB but may not be ready to accept connections immediately.
2640 set libthread-db-search-path
2641 show libthread-db-search-path
2642 Control list of directories which GDB will search for appropriate
2645 set schedule-multiple (on|off)
2646 show schedule-multiple
2647 Allow GDB to resume all threads of all processes or only threads of
2648 the current process.
2652 Use more aggressive caching for accesses to the stack. This improves
2653 performance of remote debugging (particularly backtraces) without
2654 affecting correctness.
2656 set interactive-mode (on|off|auto)
2657 show interactive-mode
2658 Control whether GDB runs in interactive mode (on) or not (off).
2659 When in interactive mode, GDB waits for the user to answer all
2660 queries. Otherwise, GDB does not wait and assumes the default
2661 answer. When set to auto (the default), GDB determines which
2662 mode to use based on the stdin settings.
2667 For program forks, this is replaced by the new more generic `info
2668 inferiors' command. To list checkpoints, you can still use the
2669 `info checkpoints' command, which was an alias for the `info forks'
2673 Replaced by the new `inferior' command. To switch between
2674 checkpoints, you can still use the `restart' command, which was an
2675 alias for the `fork' command.
2678 This is removed, since some targets don't have a notion of
2679 processes. To switch between processes, you can still use the
2680 `inferior' command using GDB's own inferior number.
2683 For program forks, this is replaced by the new more generic `kill
2684 inferior' command. To delete a checkpoint, you can still use the
2685 `delete checkpoint' command, which was an alias for the `delete
2689 For program forks, this is replaced by the new more generic `detach
2690 inferior' command. To detach a checkpoint, you can still use the
2691 `detach checkpoint' command, which was an alias for the `detach
2694 * New native configurations
2696 x86/x86_64 Darwin i[34567]86-*-darwin*
2698 x86_64 MinGW x86_64-*-mingw*
2702 Lattice Mico32 lm32-*
2703 x86 DICOS i[34567]86-*-dicos*
2704 x86_64 DICOS x86_64-*-dicos*
2707 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2708 (mingw32ce) debugging.
2714 These commands were actually not implemented on any target.
2716 *** Changes in GDB 6.8
2718 * New native configurations
2720 NetBSD/hppa hppa*-*netbsd*
2721 Xtensa GNU/Linux xtensa*-*-linux*
2725 NetBSD/hppa hppa*-*-netbsd*
2726 Xtensa GNU/Lunux xtensa*-*-linux*
2728 * Change in command line behavior -- corefiles vs. process ids.
2730 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2731 attaching to process NUMBER fails, GDB no longer attempts to open a
2732 core file named NUMBER. Attaching to a program using the -c option
2733 is no longer supported. Instead, use the '-p' or '--pid' options.
2735 * GDB can now be built as a native debugger for debugging Windows x86
2736 (mingw32) Portable Executable (PE) programs.
2738 * Pending breakpoints no longer change their number when their address
2741 * GDB now supports breakpoints with multiple locations,
2742 including breakpoints on C++ constructors, inside C++ templates,
2743 and in inlined functions.
2745 * GDB's ability to debug optimized code has been improved. GDB more
2746 accurately identifies function bodies and lexical blocks that occupy
2747 more than one contiguous range of addresses.
2749 * Target descriptions can now describe registers for PowerPC.
2751 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2752 registers on PowerPC targets.
2754 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2755 targets even when the libthread_db library is not available.
2757 * The GDB remote stub, gdbserver, now supports the new file transfer
2758 commands (remote put, remote get, and remote delete).
2760 * The GDB remote stub, gdbserver, now supports run and attach in
2761 extended-remote mode.
2763 * hppa*64*-*-hpux11* target broken
2764 The debugger is unable to start a program and fails with the following
2765 error: "Error trying to get information about dynamic linker".
2766 The gdb-6.7 release is also affected.
2768 * GDB now supports the --enable-targets= configure option to allow
2769 building a single GDB executable that supports multiple remote
2770 target architectures.
2772 * GDB now supports debugging C and C++ programs which use the
2773 Decimal Floating Point extension. In addition, the PowerPC target
2774 now has a set of pseudo-registers to inspect decimal float values
2775 stored in two consecutive float registers.
2777 * The -break-insert MI command can optionally create pending
2780 * Improved support for debugging Ada
2781 Many improvements to the Ada language support have been made. These
2783 - Better support for Ada2005 interface types
2784 - Improved handling of arrays and slices in general
2785 - Better support for Taft-amendment types
2786 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2788 - Improved command completion in Ada
2791 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2796 set print frame-arguments (all|scalars|none)
2797 show print frame-arguments
2798 The value of this variable can be changed to control which argument
2799 values should be printed by the debugger when displaying a frame.
2804 Transfer files to and from a remote target, and delete remote files.
2811 Transfer files to and from a remote target, and delete remote files.
2813 * New remote packets
2820 Open, close, read, write, and delete files on the remote system.
2823 Attach to an existing process on the remote system, in extended-remote
2827 Run a new process on the remote system, in extended-remote mode.
2829 *** Changes in GDB 6.7
2831 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2832 bfd, libiberty and opcodes, as revealed by static analysis donated by
2833 Coverity, Inc. (http://scan.coverity.com).
2835 * When looking up multiply-defined global symbols, GDB will now prefer the
2836 symbol definition in the current shared library if it was built using the
2837 -Bsymbolic linker option.
2839 * When the Text User Interface (TUI) is not configured, GDB will now
2840 recognize the -tui command-line option and print a message that the TUI
2843 * The GDB remote stub, gdbserver, now has lower overhead for high
2844 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2846 * GDB for MIPS targets now autodetects whether a remote target provides
2847 32-bit or 64-bit register values.
2849 * Support for C++ member pointers has been improved.
2851 * GDB now understands XML target descriptions, which specify the
2852 target's overall architecture. GDB can read a description from
2853 a local file or over the remote serial protocol.
2855 * Vectors of single-byte data use a new integer type which is not
2856 automatically displayed as character or string data.
2858 * The /s format now works with the print command. It displays
2859 arrays of single-byte integers and pointers to single-byte integers
2862 * Target descriptions can now describe target-specific registers,
2863 for architectures which have implemented the support (currently
2864 only ARM, M68K, and MIPS).
2866 * GDB and the GDB remote stub, gdbserver, now support the XScale
2869 * The GDB remote stub, gdbserver, has been updated to support
2870 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2871 has been rewritten to use the standard GDB remote protocol.
2873 * GDB can now step into C++ functions which are called through thunks.
2875 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2877 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2878 layout. It also supports a TextSeg= and DataSeg= response when only
2879 segment base addresses (rather than offsets) are available.
2881 * The /i format now outputs any trailing branch delay slot instructions
2882 immediately following the last instruction within the count specified.
2884 * The GDB remote protocol "T" stop reply packet now supports a
2885 "library" response. Combined with the new "qXfer:libraries:read"
2886 packet, this response allows GDB to debug shared libraries on targets
2887 where the operating system manages the list of loaded libraries (e.g.
2888 Windows and SymbianOS).
2890 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2891 (DLLs) on Windows and Windows CE targets.
2893 * GDB now supports a faster verification that a .debug file matches its binary
2894 according to its build-id signature, if the signature is present.
2900 Enable or disable hardware flow control (RTS/CTS) on the serial port
2901 when debugging using remote targets.
2903 set mem inaccessible-by-default
2904 show mem inaccessible-by-default
2905 If the target supplies a memory map, for instance via the remote
2906 protocol's "qXfer:memory-map:read" packet, setting this variable
2907 prevents GDB from accessing memory outside the memory map. This
2908 is useful for targets with memory mapped registers or which react
2909 badly to accesses of unmapped address space.
2911 set breakpoint auto-hw
2912 show breakpoint auto-hw
2913 If the target supplies a memory map, for instance via the remote
2914 protocol's "qXfer:memory-map:read" packet, setting this variable
2915 lets GDB use hardware breakpoints automatically for memory regions
2916 where it can not use software breakpoints. This covers both the
2917 "break" command and internal breakpoints used for other commands
2918 including "next" and "finish".
2921 catch exception unhandled
2922 Stop the program execution when Ada exceptions are raised.
2925 Stop the program execution when an Ada assertion failed.
2929 Set an alternate system root for target files. This is a more
2930 general version of "set solib-absolute-prefix", which is now
2931 an alias to "set sysroot".
2934 Provide extended SPU facility status information. This set of
2935 commands is available only when debugging the Cell/B.E. SPU
2938 * New native configurations
2940 OpenBSD/sh sh*-*openbsd*
2943 unset tdesc filename
2945 Use the specified local file as an XML target description, and do
2946 not query the target for its built-in description.
2950 OpenBSD/sh sh*-*-openbsd*
2951 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2952 Toshiba Media Processor mep-elf
2954 * New remote packets
2957 Ignore the specified signals; pass them directly to the debugged program
2958 without stopping other threads or reporting them to GDB.
2960 qXfer:features:read:
2961 Read an XML target description from the target, which describes its
2966 Read or write contents of an spufs file on the target system. These
2967 packets are available only on the Cell/B.E. SPU architecture.
2969 qXfer:libraries:read:
2970 Report the loaded shared libraries. Combined with new "T" packet
2971 response, this packet allows GDB to debug shared libraries on
2972 targets where the operating system manages the list of loaded
2973 libraries (e.g. Windows and SymbianOS).
2977 Support for these obsolete configurations has been removed.
2985 i[34567]86-*-lynxos*
2986 i[34567]86-*-netware*
2987 i[34567]86-*-sco3.2v5*
2988 i[34567]86-*-sco3.2v4*
2990 i[34567]86-*-sysv4.2*
2993 i[34567]86-*-unixware2*
2994 i[34567]86-*-unixware*
3003 * Other removed features
3010 Various m68k-only ROM monitors.
3017 Various Renesas ROM monitors and debugging interfaces for SH and
3022 Support for a Macraigor serial interface to on-chip debugging.
3023 GDB does not directly support the newer parallel or USB
3028 A debug information format. The predecessor to DWARF 2 and
3029 DWARF 3, which are still supported.
3031 Support for the HP aCC compiler on HP-UX/PA-RISC
3033 SOM-encapsulated symbolic debugging information, automatic
3034 invocation of pxdb, and the aCC custom C++ ABI. This does not
3035 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3036 with aCC can still be debugged on an assembly level.
3038 MIPS ".pdr" sections
3040 A MIPS-specific format used to describe stack frame layout
3041 in debugging information.
3045 GDB could work with an older version of Guile to debug
3046 the interpreter and Scheme programs running in it.
3048 set mips stack-arg-size
3049 set mips saved-gpreg-size
3051 Use "set mips abi" to control parameter passing for MIPS.
3053 *** Changes in GDB 6.6
3058 Cell Broadband Engine SPU spu-elf
3060 * GDB can now be configured as a cross-debugger targeting native Windows
3061 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3062 running on a Windows system over TCP/IP to debug Windows programs.
3064 * The GDB remote stub, gdbserver, has been updated to support Windows and
3065 Cygwin debugging. Both single-threaded and multi-threaded programs are
3068 * The "set trust-readonly-sections" command works again. This command was
3069 broken in GDB 6.3, 6.4, and 6.5.
3071 * The "load" command now supports writing to flash memory, if the remote
3072 stub provides the required support.
3074 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3075 longer requires symbolic debug information (e.g. DWARF-2).
3080 unset substitute-path
3081 show substitute-path
3082 Manage a list of substitution rules that GDB uses to rewrite the name
3083 of the directories where the sources are located. This can be useful
3084 for instance when the sources were moved to a different location
3085 between compilation and debugging.
3089 Print each CLI command as it is executed. Each command is prefixed with
3090 a number of `+' symbols representing the nesting depth.
3091 The source command now has a `-v' option to enable the same feature.
3095 The ARM Demon monitor support (RDP protocol, "target rdp").
3097 Kernel Object Display, an embedded debugging feature which only worked with
3098 an obsolete version of Cisco IOS.
3100 The 'set download-write-size' and 'show download-write-size' commands.
3102 * New remote packets
3105 Tell a stub about GDB client features, and request remote target features.
3106 The first feature implemented is PacketSize, which allows the target to
3107 specify the size of packets it can handle - to minimize the number of
3108 packets required and improve performance when connected to a remote
3112 Fetch an OS auxilliary vector from the remote stub. This packet is a
3113 more efficient replacement for qPart:auxv:read.
3115 qXfer:memory-map:read:
3116 Fetch a memory map from the remote stub, including information about
3117 RAM, ROM, and flash memory devices.
3122 Erase and program a flash memory device.
3124 * Removed remote packets
3127 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3128 used it, and only gdbserver implemented it.
3130 *** Changes in GDB 6.5
3134 Renesas M32C/M16C m32c-elf
3136 Morpho Technologies ms1 ms1-elf
3140 init-if-undefined Initialize a convenience variable, but
3141 only if it doesn't already have a value.
3143 The following commands are presently only implemented for native GNU/Linux:
3145 checkpoint Save a snapshot of the program state.
3147 restart <n> Return the program state to a
3148 previously saved state.
3150 info checkpoints List currently saved checkpoints.
3152 delete-checkpoint <n> Delete a previously saved checkpoint.
3154 set|show detach-on-fork Tell gdb whether to detach from a newly
3155 forked process, or to keep debugging it.
3157 info forks List forks of the user program that
3158 are available to be debugged.
3160 fork <n> Switch to debugging one of several
3161 forks of the user program that are
3162 available to be debugged.
3164 delete-fork <n> Delete a fork from the list of forks
3165 that are available to be debugged (and
3166 kill the forked process).
3168 detach-fork <n> Delete a fork from the list of forks
3169 that are available to be debugged (and
3170 allow the process to continue).
3174 Morpho Technologies ms2 ms1-elf
3176 * Improved Windows host support
3178 GDB now builds as a cross debugger hosted on i686-mingw32, including
3179 native console support, and remote communications using either
3180 network sockets or serial ports.
3182 * Improved Modula-2 language support
3184 GDB can now print most types in the Modula-2 syntax. This includes:
3185 basic types, set types, record types, enumerated types, range types,
3186 pointer types and ARRAY types. Procedure var parameters are correctly
3187 printed and hexadecimal addresses and character constants are also
3188 written in the Modula-2 syntax. Best results can be obtained by using
3189 GNU Modula-2 together with the -gdwarf-2 command line option.
3193 The ARM rdi-share module.
3195 The Netware NLM debug server.
3197 *** Changes in GDB 6.4
3199 * New native configurations
3201 OpenBSD/arm arm*-*-openbsd*
3202 OpenBSD/mips64 mips64-*-openbsd*
3206 Morpho Technologies ms1 ms1-elf
3208 * New command line options
3210 --batch-silent As for --batch, but totally silent.
3211 --return-child-result The debugger will exist with the same value
3212 the child (debugged) program exited with.
3213 --eval-command COMMAND, -ex COMMAND
3214 Execute a single GDB CLI command. This may be
3215 specified multiple times and in conjunction
3216 with the --command (-x) option.
3218 * Deprecated commands removed
3220 The following commands, that were deprecated in 2000, have been
3224 set|show arm disassembly-flavor set|show arm disassembler
3225 othernames set arm disassembler
3226 set|show remotedebug set|show debug remote
3227 set|show archdebug set|show debug arch
3228 set|show eventdebug set|show debug event
3231 * New BSD user-level threads support
3233 It is now possible to debug programs using the user-level threads
3234 library on OpenBSD and FreeBSD. Currently supported (target)
3237 FreeBSD/amd64 x86_64-*-freebsd*
3238 FreeBSD/i386 i386-*-freebsd*
3239 OpenBSD/i386 i386-*-openbsd*
3241 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3242 are not yet supported.
3244 * New support for Matsushita MN10300 w/sim added
3245 (Work in progress). mn10300-elf.
3247 * REMOVED configurations and files
3249 VxWorks and the XDR protocol *-*-vxworks
3250 Motorola MCORE mcore-*-*
3251 National Semiconductor NS32000 ns32k-*-*
3253 * New "set print array-indexes" command
3255 After turning this setting "on", GDB prints the index of each element
3256 when displaying arrays. The default is "off" to preserve the previous
3259 * VAX floating point support
3261 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3263 * User-defined command support
3265 In addition to using $arg0..$arg9 for argument passing, it is now possible
3266 to use $argc to determine now many arguments have been passed. See the
3267 section on user-defined commands in the user manual for more information.
3269 *** Changes in GDB 6.3:
3271 * New command line option
3273 GDB now accepts -l followed by a number to set the timeout for remote
3276 * GDB works with GCC -feliminate-dwarf2-dups
3278 GDB now supports a more compact representation of DWARF-2 debug
3279 information using DW_FORM_ref_addr references. These are produced
3280 by GCC with the option -feliminate-dwarf2-dups and also by some
3281 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3282 to use -feliminate-dwarf2-dups.
3284 * Internationalization
3286 When supported by the host system, GDB will be built with
3287 internationalization (libintl). The task of marking up the sources is
3288 continued, we're looking forward to our first translation.
3292 Initial support for debugging programs compiled with the GNAT
3293 implementation of the Ada programming language has been integrated
3294 into GDB. In this release, support is limited to expression evaluation.
3296 * New native configurations
3298 GNU/Linux/m32r m32r-*-linux-gnu
3302 GDB's remote protocol now includes support for the 'p' packet. This
3303 packet is used to fetch individual registers from a remote inferior.
3305 * END-OF-LIFE registers[] compatibility module
3307 GDB's internal register infrastructure has been completely rewritten.
3308 The new infrastructure making possible the implementation of key new
3309 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3312 GDB 6.3 will be the last release to include the the registers[]
3313 compatibility module that allowed out-of-date configurations to
3314 continue to work. This change directly impacts the following
3324 powerpc bdm protocol
3326 Unless there is activity to revive these configurations, they will be
3327 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3329 * OBSOLETE configurations and files
3331 Configurations that have been declared obsolete in this release have
3332 been commented out. Unless there is activity to revive these
3333 configurations, the next release of GDB will have their sources
3334 permanently REMOVED.
3343 *** Changes in GDB 6.2.1:
3345 * MIPS `break main; run' gave an heuristic-fence-post warning
3347 When attempting to run even a simple program, a warning about
3348 heuristic-fence-post being hit would be reported. This problem has
3351 * MIPS IRIX 'long double' crashed GDB
3353 When examining a long double variable, GDB would get a segmentation
3354 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3355 IRIX long double values).
3359 A bug in the VAX stack code was causing problems with the "next"
3360 command. This problem has been fixed.
3362 *** Changes in GDB 6.2:
3364 * Fix for ``many threads''
3366 On GNU/Linux systems that use the NPTL threads library, a program
3367 rapidly creating and deleting threads would confuse GDB leading to the
3370 ptrace: No such process.
3371 thread_db_get_info: cannot get thread info: generic error
3373 This problem has been fixed.
3375 * "-async" and "-noasync" options removed.
3377 Support for the broken "-noasync" option has been removed (it caused
3380 * New ``start'' command.
3382 This command runs the program until the begining of the main procedure.
3384 * New BSD Kernel Data Access Library (libkvm) interface
3386 Using ``target kvm'' it is now possible to debug kernel core dumps and
3387 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3388 platforms. Currently supported (native-only) configurations are:
3390 FreeBSD/amd64 x86_64-*-freebsd*
3391 FreeBSD/i386 i?86-*-freebsd*
3392 NetBSD/i386 i?86-*-netbsd*
3393 NetBSD/m68k m68*-*-netbsd*
3394 NetBSD/sparc sparc-*-netbsd*
3395 OpenBSD/amd64 x86_64-*-openbsd*
3396 OpenBSD/i386 i?86-*-openbsd*
3397 OpenBSD/m68k m68*-openbsd*
3398 OpenBSD/sparc sparc-*-openbsd*
3400 * Signal trampoline code overhauled
3402 Many generic problems with GDB's signal handling code have been fixed.
3403 These include: backtraces through non-contiguous stacks; recognition
3404 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3405 call; backtrace through a signal trampoline; step into and out of
3406 signal handlers; and single-stepping in the signal trampoline.
3408 Please note that kernel bugs are a limiting factor here. These
3409 features have been shown to work on an s390 GNU/Linux system that
3410 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3412 * Cygwin support for DWARF 2 added.
3414 * New native configurations
3416 GNU/Linux/hppa hppa*-*-linux*
3417 OpenBSD/hppa hppa*-*-openbsd*
3418 OpenBSD/m68k m68*-*-openbsd*
3419 OpenBSD/m88k m88*-*-openbsd*
3420 OpenBSD/powerpc powerpc-*-openbsd*
3421 NetBSD/vax vax-*-netbsd*
3422 OpenBSD/vax vax-*-openbsd*
3424 * END-OF-LIFE frame compatibility module
3426 GDB's internal frame infrastructure has been completely rewritten.
3427 The new infrastructure making it possible to support key new features
3428 including DWARF 2 Call Frame Information. To aid in the task of
3429 migrating old configurations to this new infrastructure, a
3430 compatibility module, that allowed old configurations to continue to
3431 work, was also included.
3433 GDB 6.2 will be the last release to include this frame compatibility
3434 module. This change directly impacts the following configurations:
3444 Unless there is activity to revive these configurations, they will be
3445 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3447 * REMOVED configurations and files
3449 Sun 3, running SunOS 3 m68*-*-sunos3*
3450 Sun 3, running SunOS 4 m68*-*-sunos4*
3451 Sun 2, running SunOS 3 m68000-*-sunos3*
3452 Sun 2, running SunOS 4 m68000-*-sunos4*
3453 Motorola 680x0 running LynxOS m68*-*-lynxos*
3454 AT&T 3b1/Unix pc m68*-att-*
3455 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3456 decstation mips-dec-* mips-little-*
3457 riscos mips-*-riscos* mips-*-sysv*
3458 sonymips mips-sony-*
3459 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3461 *** Changes in GDB 6.1.1:
3463 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3465 The TUI (Text-mode User Interface) is now built as part of a default
3466 GDB configuration. It is enabled by either selecting the TUI with the
3467 command line option "-i=tui" or by running the separate "gdbtui"
3468 program. For more information on the TUI, see the manual "Debugging
3471 * Pending breakpoint support (also included in GDB 6.1)
3473 Support has been added to allow you to specify breakpoints in shared
3474 libraries that have not yet been loaded. If a breakpoint location
3475 cannot be found, and the "breakpoint pending" option is set to auto,
3476 GDB queries you if you wish to make the breakpoint pending on a future
3477 shared-library load. If and when GDB resolves the breakpoint symbol,
3478 the pending breakpoint is removed as one or more regular breakpoints
3481 Pending breakpoints are very useful for GCJ Java debugging.
3483 * Fixed ISO-C build problems
3485 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3486 non ISO-C code that stopped them being built using a more strict ISO-C
3487 compiler (e.g., IBM's C compiler).
3489 * Fixed build problem on IRIX 5
3491 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3492 wasn't able to compile compile on an IRIX 5 system.
3494 * Added execute permission to gdb/gdbserver/configure
3496 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3497 permission. This bug would cause configure to fail on a number of
3498 systems (Solaris, IRIX). Ref: server/519.
3500 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3502 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3503 has been updated to use constant array sizes.
3505 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3507 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3508 its generated DWARF Call Frame Info. This encoding was causing GDB to
3509 panic, that panic has been fixed. Ref: gdb/1628.
3511 * Fixed a problem when examining parameters in shared library code.
3513 When examining parameters in optimized shared library code generated
3514 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3515 not available''. GDB now correctly displays the variable's value.
3517 *** Changes in GDB 6.1:
3519 * Removed --with-mmalloc
3521 Support for the mmalloc memory manager has been removed, as it
3522 conflicted with the internal gdb byte cache.
3524 * Changes in AMD64 configurations
3526 The AMD64 target now includes the %cs and %ss registers. As a result
3527 the AMD64 remote protocol has changed; this affects the floating-point
3528 and SSE registers. If you rely on those registers for your debugging,
3529 you should upgrade gdbserver on the remote side.
3531 * Revised SPARC target
3533 The SPARC target has been completely revised, incorporating the
3534 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3535 support for LynxOS and SunOS 4 has been dropped. Calling functions
3536 from within GDB on operating systems with a non-executable stack
3537 (Solaris, OpenBSD) now works.
3541 GDB has a new C++ demangler which does a better job on the mangled
3542 names generated by current versions of g++. It also runs faster, so
3543 with this and other changes gdb should now start faster on large C++
3546 * DWARF 2 Location Expressions
3548 GDB support for location expressions has been extended to support function
3549 arguments and frame bases. Older versions of GDB could crash when they
3552 * C++ nested types and namespaces
3554 GDB's support for nested types and namespaces in C++ has been
3555 improved, especially if you use the DWARF 2 debugging format. (This
3556 is the default for recent versions of GCC on most platforms.)
3557 Specifically, if you have a class "Inner" defined within a class or
3558 namespace "Outer", then GDB realizes that the class's name is
3559 "Outer::Inner", not simply "Inner". This should greatly reduce the
3560 frequency of complaints about not finding RTTI symbols. In addition,
3561 if you are stopped at inside of a function defined within a namespace,
3562 GDB modifies its name lookup accordingly.
3564 * New native configurations
3566 NetBSD/amd64 x86_64-*-netbsd*
3567 OpenBSD/amd64 x86_64-*-openbsd*
3568 OpenBSD/alpha alpha*-*-openbsd*
3569 OpenBSD/sparc sparc-*-openbsd*
3570 OpenBSD/sparc64 sparc64-*-openbsd*
3572 * New debugging protocols
3574 M32R with SDI protocol m32r-*-elf*
3576 * "set prompt-escape-char" command deleted.
3578 The command "set prompt-escape-char" has been deleted. This command,
3579 and its very obscure effet on GDB's prompt, was never documented,
3580 tested, nor mentioned in the NEWS file.
3582 * OBSOLETE configurations and files
3584 Configurations that have been declared obsolete in this release have
3585 been commented out. Unless there is activity to revive these
3586 configurations, the next release of GDB will have their sources
3587 permanently REMOVED.
3589 Sun 3, running SunOS 3 m68*-*-sunos3*
3590 Sun 3, running SunOS 4 m68*-*-sunos4*
3591 Sun 2, running SunOS 3 m68000-*-sunos3*
3592 Sun 2, running SunOS 4 m68000-*-sunos4*
3593 Motorola 680x0 running LynxOS m68*-*-lynxos*
3594 AT&T 3b1/Unix pc m68*-att-*
3595 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3596 decstation mips-dec-* mips-little-*
3597 riscos mips-*-riscos* mips-*-sysv*
3598 sonymips mips-sony-*
3599 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3601 * REMOVED configurations and files
3603 SGI Irix-4.x mips-sgi-irix4 or iris4
3604 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3605 Z8000 simulator z8k-zilog-none or z8ksim
3606 Matsushita MN10200 w/simulator mn10200-*-*
3607 H8/500 simulator h8500-hitachi-hms or h8500hms
3608 HP/PA running BSD hppa*-*-bsd*
3609 HP/PA running OSF/1 hppa*-*-osf*
3610 HP/PA Pro target hppa*-*-pro*
3611 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3612 386BSD i[3456]86-*-bsd*
3613 Sequent family i[3456]86-sequent-sysv4*
3614 i[3456]86-sequent-sysv*
3615 i[3456]86-sequent-bsd*
3616 SPARC running LynxOS sparc-*-lynxos*
3617 SPARC running SunOS 4 sparc-*-sunos4*
3618 Tsqware Sparclet sparclet-*-*
3619 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3621 *** Changes in GDB 6.0:
3625 Support for debugging the Objective-C programming language has been
3626 integrated into GDB.
3628 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3630 DWARF 2's Call Frame Information makes available compiler generated
3631 information that more exactly describes the program's run-time stack.
3632 By using this information, GDB is able to provide more robust stack
3635 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3636 have been updated to use a new backtrace mechanism which includes
3637 DWARF 2 CFI support.
3641 GDB's remote protocol has been extended to include support for hosted
3642 file I/O (where the remote target uses GDB's file system). See GDB's
3643 remote protocol documentation for details.
3645 * All targets using the new architecture framework.
3647 All of GDB's targets have been updated to use the new internal
3648 architecture framework. The way is now open for future GDB releases
3649 to include cross-architecture native debugging support (i386 on amd64,
3652 * GNU/Linux's Thread Local Storage (TLS)
3654 GDB now includes support for for the GNU/Linux implementation of
3655 per-thread variables.
3657 * GNU/Linux's Native POSIX Thread Library (NPTL)
3659 GDB's thread code has been updated to work with either the new
3660 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3662 * Separate debug info.
3664 GDB, in conjunction with BINUTILS, now supports a mechanism for
3665 automatically loading debug information from a separate file. Instead
3666 of shipping full debug and non-debug versions of system libraries,
3667 system integrators can now instead ship just the stripped libraries
3668 and optional debug files.
3670 * DWARF 2 Location Expressions
3672 DWARF 2 Location Expressions allow the compiler to more completely
3673 describe the location of variables (even in optimized code) to the
3676 GDB now includes preliminary support for location expressions (support
3677 for DW_OP_piece is still missing).
3681 A number of long standing bugs that caused GDB to die while starting a
3682 Java application have been fixed. GDB's Java support is now
3683 considered "useable".
3685 * GNU/Linux support for fork, vfork, and exec.
3687 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3688 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3691 * GDB supports logging output to a file
3693 There are two new commands, "set logging" and "show logging", which can be
3694 used to capture GDB's output to a file.
3696 * The meaning of "detach" has changed for gdbserver
3698 The "detach" command will now resume the application, as documented. To
3699 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3702 * d10v, m68hc11 `regs' command deprecated
3704 The `info registers' command has been updated so that it displays the
3705 registers using a format identical to the old `regs' command.
3709 A new command, "maint set profile on/off", has been added. This command can
3710 be used to enable or disable profiling while running GDB, to profile a
3711 session or a set of commands. In addition there is a new configure switch,
3712 "--enable-profiling", which will cause GDB to be compiled with profiling
3713 data, for more informative profiling results.
3715 * Default MI syntax changed to "mi2".
3717 The default MI (machine interface) syntax, enabled by the command line
3718 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3719 "mi1", can be enabled by specifying the option "-i=mi1".
3721 Support for the original "mi0" syntax (included in GDB 5.0) has been
3724 Fix for gdb/192: removed extraneous space when displaying frame level.
3725 Fix for gdb/672: update changelist is now output in mi list format.
3726 Fix for gdb/702: a -var-assign that updates the value now shows up
3727 in a subsequent -var-update.
3729 * New native configurations.
3731 FreeBSD/amd64 x86_64-*-freebsd*
3733 * Multi-arched targets.
3735 HP/PA HPUX11 hppa*-*-hpux*
3736 Renesas M32R/D w/simulator m32r-*-elf*
3738 * OBSOLETE configurations and files
3740 Configurations that have been declared obsolete in this release have
3741 been commented out. Unless there is activity to revive these
3742 configurations, the next release of GDB will have their sources
3743 permanently REMOVED.
3745 Z8000 simulator z8k-zilog-none or z8ksim
3746 Matsushita MN10200 w/simulator mn10200-*-*
3747 H8/500 simulator h8500-hitachi-hms or h8500hms
3748 HP/PA running BSD hppa*-*-bsd*
3749 HP/PA running OSF/1 hppa*-*-osf*
3750 HP/PA Pro target hppa*-*-pro*
3751 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3752 Sequent family i[3456]86-sequent-sysv4*
3753 i[3456]86-sequent-sysv*
3754 i[3456]86-sequent-bsd*
3755 Tsqware Sparclet sparclet-*-*
3756 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3758 * REMOVED configurations and files
3761 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3762 IBM AIX PS/2 i[3456]86-*-aix
3763 i386 running Mach 3.0 i[3456]86-*-mach3*
3764 i386 running Mach i[3456]86-*-mach*
3765 i386 running OSF/1 i[3456]86-*osf1mk*
3766 HP/Apollo 68k Family m68*-apollo*-sysv*,
3768 m68*-hp-bsd*, m68*-hp-hpux*
3769 Argonaut Risc Chip (ARC) arc-*-*
3770 Mitsubishi D30V d30v-*-*
3771 Fujitsu FR30 fr30-*-elf*
3772 OS/9000 i[34]86-*-os9k
3773 I960 with MON960 i960-*-coff
3775 * MIPS $fp behavior changed
3777 The convenience variable $fp, for the MIPS, now consistently returns
3778 the address of the current frame's base. Previously, depending on the
3779 context, $fp could refer to either $sp or the current frame's base
3780 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3781 The GNU Source-Level Debugger''.
3783 *** Changes in GDB 5.3:
3785 * GNU/Linux shared library multi-threaded performance improved.
3787 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3788 `/proc', in preference to `ptrace' for memory reads. This may result
3789 in an improvement in the start-up time of multi-threaded, shared
3790 library applications when run under GDB. One GDB user writes: ``loads
3791 shared libs like mad''.
3793 * ``gdbserver'' now supports multi-threaded applications on some targets
3795 Support for debugging multi-threaded applications which use
3796 the GNU/Linux LinuxThreads package has been added for
3797 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3798 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3800 * GDB now supports C/C++ preprocessor macros.
3802 GDB now expands preprocessor macro invocations in C/C++ expressions,
3803 and provides various commands for showing macro definitions and how
3806 The new command `macro expand EXPRESSION' expands any macro
3807 invocations in expression, and shows the result.
3809 The new command `show macro MACRO-NAME' shows the definition of the
3810 macro named MACRO-NAME, and where it was defined.
3812 Most compilers don't include information about macros in the debugging
3813 information by default. In GCC 3.1, for example, you need to compile
3814 your program with the options `-gdwarf-2 -g3'. If the macro
3815 information is present in the executable, GDB will read it.
3817 * Multi-arched targets.
3819 DEC Alpha (partial) alpha*-*-*
3820 DEC VAX (partial) vax-*-*
3822 National Semiconductor NS32000 (partial) ns32k-*-*
3823 Motorola 68000 (partial) m68k-*-*
3824 Motorola MCORE mcore-*-*
3828 Fujitsu FRV architecture added by Red Hat frv*-*-*
3831 * New native configurations
3833 Alpha NetBSD alpha*-*-netbsd*
3834 SH NetBSD sh*-*-netbsdelf*
3835 MIPS NetBSD mips*-*-netbsd*
3836 UltraSPARC NetBSD sparc64-*-netbsd*
3838 * OBSOLETE configurations and files
3840 Configurations that have been declared obsolete in this release have
3841 been commented out. Unless there is activity to revive these
3842 configurations, the next release of GDB will have their sources
3843 permanently REMOVED.
3845 Mitsubishi D30V d30v-*-*
3846 OS/9000 i[34]86-*-os9k
3847 IBM AIX PS/2 i[3456]86-*-aix
3848 Fujitsu FR30 fr30-*-elf*
3849 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3850 Argonaut Risc Chip (ARC) arc-*-*
3851 i386 running Mach 3.0 i[3456]86-*-mach3*
3852 i386 running Mach i[3456]86-*-mach*
3853 i386 running OSF/1 i[3456]86-*osf1mk*
3854 HP/Apollo 68k Family m68*-apollo*-sysv*,
3856 m68*-hp-bsd*, m68*-hp-hpux*
3857 I960 with MON960 i960-*-coff
3859 * OBSOLETE languages
3861 CHILL, a Pascal like language used by telecommunications companies.
3863 * REMOVED configurations and files
3865 AMD 29k family via UDI a29k-amd-udi, udi29k
3866 A29K VxWorks a29k-*-vxworks
3867 AMD 29000 embedded, using EBMON a29k-none-none
3868 AMD 29000 embedded with COFF a29k-none-coff
3869 AMD 29000 embedded with a.out a29k-none-aout
3871 testsuite/gdb.hp/gdb.threads-hp/ directory
3873 * New command "set max-user-call-depth <nnn>"
3875 This command allows the user to limit the call depth of user-defined
3876 commands. The default is 1024.
3878 * Changes in FreeBSD/i386 native debugging.
3880 Support for the "generate-core-file" has been added.
3882 * New commands "dump", "append", and "restore".
3884 These commands allow data to be copied from target memory
3885 to a bfd-format or binary file (dump and append), and back
3886 from a file into memory (restore).
3888 * Improved "next/step" support on multi-processor Alpha Tru64.
3890 The previous single-step mechanism could cause unpredictable problems,
3891 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3892 of a software single-step mechanism prevents this.
3894 *** Changes in GDB 5.2.1:
3902 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3903 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3904 Fix, by Joel Brobecker imported from mainline.
3906 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3907 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3908 Fix, by Fred Fish, imported from mainline.
3910 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3911 Surprisingly enough, it works now.
3912 By Michal Ludvig, imported from mainline.
3914 i386 hardware watchpoint support:
3915 avoid misses on second run for some targets.
3916 By Pierre Muller, imported from mainline.
3918 *** Changes in GDB 5.2:
3920 * New command "set trust-readonly-sections on[off]".
3922 This command is a hint that tells gdb that read-only sections
3923 really are read-only (ie. that their contents will not change).
3924 In this mode, gdb will go to the object file rather than the
3925 target to read memory from read-only sections (such as ".text").
3926 This can be a significant performance improvement on some
3927 (notably embedded) targets.
3929 * New command "generate-core-file" (or "gcore").
3931 This new gdb command allows the user to drop a core file of the child
3932 process state at any time. So far it's been implemented only for
3933 GNU/Linux and Solaris, but should be relatively easily ported to other
3934 hosts. Argument is core file name (defaults to core.<pid>).
3936 * New command line option
3938 GDB now accepts --pid or -p followed by a process id.
3940 * Change in command line behavior -- corefiles vs. process ids.
3942 There is a subtle behavior in the way in which GDB handles
3943 command line arguments. The first non-flag argument is always
3944 a program to debug, but the second non-flag argument may either
3945 be a corefile or a process id. Previously, GDB would attempt to
3946 open the second argument as a corefile, and if that failed, would
3947 issue a superfluous error message and then attempt to attach it as
3948 a process. Now, if the second argument begins with a non-digit,
3949 it will be treated as a corefile. If it begins with a digit,
3950 GDB will attempt to attach it as a process, and if no such process
3951 is found, will then attempt to open it as a corefile.
3953 * Changes in ARM configurations.
3955 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3956 configuration is fully multi-arch.
3958 * New native configurations
3960 ARM NetBSD arm*-*-netbsd*
3961 x86 OpenBSD i[3456]86-*-openbsd*
3962 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3963 Sparc64 running FreeBSD sparc64-*-freebsd*
3967 Sanyo XStormy16 xstormy16-elf
3969 * OBSOLETE configurations and files
3971 Configurations that have been declared obsolete in this release have
3972 been commented out. Unless there is activity to revive these
3973 configurations, the next release of GDB will have their sources
3974 permanently REMOVED.
3976 AMD 29k family via UDI a29k-amd-udi, udi29k
3977 A29K VxWorks a29k-*-vxworks
3978 AMD 29000 embedded, using EBMON a29k-none-none
3979 AMD 29000 embedded with COFF a29k-none-coff
3980 AMD 29000 embedded with a.out a29k-none-aout
3982 testsuite/gdb.hp/gdb.threads-hp/ directory
3984 * REMOVED configurations and files
3986 TI TMS320C80 tic80-*-*
3988 PowerPC Solaris powerpcle-*-solaris*
3989 PowerPC Windows NT powerpcle-*-cygwin32
3990 PowerPC Netware powerpc-*-netware*
3991 Harris/CXUX m88k m88*-harris-cxux*
3992 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3993 ns32k-utek-sysv* ns32k-utek-*
3994 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3995 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3996 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3997 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3998 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4000 * Changes to command line processing
4002 The new `--args' feature can be used to specify command-line arguments
4003 for the inferior from gdb's command line.
4005 * Changes to key bindings
4007 There is a new `operate-and-get-next' function bound to `C-o'.
4009 *** Changes in GDB 5.1.1
4011 Fix compile problem on DJGPP.
4013 Fix a problem with floating-point registers on the i386 being
4016 Fix to stop GDB crashing on .debug_str debug info.
4018 Numerous documentation fixes.
4020 Numerous testsuite fixes.
4022 *** Changes in GDB 5.1:
4024 * New native configurations
4026 Alpha FreeBSD alpha*-*-freebsd*
4027 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4028 MIPS GNU/Linux mips*-*-linux*
4029 MIPS SGI Irix 6.x mips*-sgi-irix6*
4030 ia64 AIX ia64-*-aix*
4031 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4035 Motorola 68HC11 and 68HC12 m68hc11-elf
4037 UltraSparc running GNU/Linux sparc64-*-linux*
4039 * OBSOLETE configurations and files
4041 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4042 Harris/CXUX m88k m88*-harris-cxux*
4043 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4044 ns32k-utek-sysv* ns32k-utek-*
4045 TI TMS320C80 tic80-*-*
4047 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4048 PowerPC Solaris powerpcle-*-solaris*
4049 PowerPC Windows NT powerpcle-*-cygwin32
4050 PowerPC Netware powerpc-*-netware*
4051 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4052 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4053 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4054 Apple Macintosh (MPW) host N/A
4056 stuff.c (Program to stuff files into a specially prepared space in kdb)
4057 kdb-start.c (Main loop for the standalone kernel debugger)
4059 Configurations that have been declared obsolete in this release have
4060 been commented out. Unless there is activity to revive these
4061 configurations, the next release of GDB will have their sources
4062 permanently REMOVED.
4064 * REMOVED configurations and files
4066 Altos 3068 m68*-altos-*
4067 Convex c1-*-*, c2-*-*
4069 ARM RISCix arm-*-* (as host)
4073 * GDB has been converted to ISO C.
4075 GDB's source code has been converted to ISO C. In particular, the
4076 sources are fully protoized, and rely on standard headers being
4081 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4083 * The MI enabled by default.
4085 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4086 revised and enabled by default. Packages which use GDB as a debugging
4087 engine behind a UI or another front end are encouraged to switch to
4088 using the GDB/MI interface, instead of the old annotations interface
4089 which is now deprecated.
4091 * Support for debugging Pascal programs.
4093 GDB now includes support for debugging Pascal programs. The following
4094 main features are supported:
4096 - Pascal-specific data types such as sets;
4098 - automatic recognition of Pascal sources based on file-name
4101 - Pascal-style display of data types, variables, and functions;
4103 - a Pascal expression parser.
4105 However, some important features are not yet supported.
4107 - Pascal string operations are not supported at all;
4109 - there are some problems with boolean types;
4111 - Pascal type hexadecimal constants are not supported
4112 because they conflict with the internal variables format;
4114 - support for Pascal objects and classes is not full yet;
4116 - unlike Pascal, GDB is case-sensitive for symbol names.
4118 * Changes in completion.
4120 Commands such as `shell', `run' and `set args', which pass arguments
4121 to inferior programs, now complete on file names, similar to what
4122 users expect at the shell prompt.
4124 Commands which accept locations, such as `disassemble', `print',
4125 `breakpoint', `until', etc. now complete on filenames as well as
4126 program symbols. Thus, if you type "break foob TAB", and the source
4127 files linked into the programs include `foobar.c', that file name will
4128 be one of the candidates for completion. However, file names are not
4129 considered for completion after you typed a colon that delimits a file
4130 name from a name of a function in that file, as in "break foo.c:bar".
4132 `set demangle-style' completes on available demangling styles.
4134 * New platform-independent commands:
4136 It is now possible to define a post-hook for a command as well as a
4137 hook that runs before the command. For more details, see the
4138 documentation of `hookpost' in the GDB manual.
4140 * Changes in GNU/Linux native debugging.
4142 Support for debugging multi-threaded programs has been completely
4143 revised for all platforms except m68k and sparc. You can now debug as
4144 many threads as your system allows you to have.
4146 Attach/detach is supported for multi-threaded programs.
4148 Support for SSE registers was added for x86. This doesn't work for
4149 multi-threaded programs though.
4151 * Changes in MIPS configurations.
4153 Multi-arch support is enabled for all MIPS configurations.
4155 GDB can now be built as native debugger on SGI Irix 6.x systems for
4156 debugging n32 executables. (Debugging 64-bit executables is not yet
4159 * Unified support for hardware watchpoints in all x86 configurations.
4161 Most (if not all) native x86 configurations support hardware-assisted
4162 breakpoints and watchpoints in a unified manner. This support
4163 implements debug register sharing between watchpoints, which allows to
4164 put a virtually infinite number of watchpoints on the same address,
4165 and also supports watching regions up to 16 bytes with several debug
4168 The new maintenance command `maintenance show-debug-regs' toggles
4169 debugging print-outs in functions that insert, remove, and test
4170 watchpoints and hardware breakpoints.
4172 * Changes in the DJGPP native configuration.
4174 New command ``info dos sysinfo'' displays assorted information about
4175 the CPU, OS, memory, and DPMI server.
4177 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4178 display information about segment descriptors stored in GDT, LDT, and
4181 New commands ``info dos pde'' and ``info dos pte'' display entries
4182 from Page Directory and Page Tables (for now works with CWSDPMI only).
4183 New command ``info dos address-pte'' displays the Page Table entry for
4184 a given linear address.
4186 GDB can now pass command lines longer than 126 characters to the
4187 program being debugged (requires an update to the libdbg.a library
4188 which is part of the DJGPP development kit).
4190 DWARF2 debug info is now supported.
4192 It is now possible to `step' and `next' through calls to `longjmp'.
4194 * Changes in documentation.
4196 All GDB documentation was converted to GFDL, the GNU Free
4197 Documentation License.
4199 Tracepoints-related commands are now fully documented in the GDB
4202 TUI, the Text-mode User Interface, is now documented in the manual.
4204 Tracepoints-related commands are now fully documented in the GDB
4207 The "GDB Internals" manual now has an index. It also includes
4208 documentation of `ui_out' functions, GDB coding standards, x86
4209 hardware watchpoints, and memory region attributes.
4211 * GDB's version number moved to ``version.in''
4213 The Makefile variable VERSION has been replaced by the file
4214 ``version.in''. People creating GDB distributions should update the
4215 contents of this file.
4219 GUD support is now a standard part of the EMACS distribution.
4221 *** Changes in GDB 5.0:
4223 * Improved support for debugging FP programs on x86 targets
4225 Unified and much-improved support for debugging floating-point
4226 programs on all x86 targets. In particular, ``info float'' now
4227 displays the FP registers in the same format on all x86 targets, with
4228 greater level of detail.
4230 * Improvements and bugfixes in hardware-assisted watchpoints
4232 It is now possible to watch array elements, struct members, and
4233 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4234 on x86 targets no longer erroneously trigger when the address is
4237 * Improvements in the native DJGPP version of GDB
4239 The distribution now includes all the scripts and auxiliary files
4240 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4241 machines ``out of the box''.
4243 The DJGPP version can now debug programs that use signals. It is
4244 possible to catch signals that happened in the debuggee, deliver
4245 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4246 would kill the program being debugged.) Programs that hook hardware
4247 interrupts (keyboard, timer, etc.) can also be debugged.
4249 It is now possible to debug DJGPP programs that redirect their
4250 standard handles or switch them to raw (as opposed to cooked) mode, or
4251 even close them. The command ``run < foo > bar'' works as expected,
4252 and ``info terminal'' reports useful information about the debuggee's
4253 terminal, including raw/cooked mode, redirection, etc.
4255 The DJGPP version now uses termios functions for console I/O, which
4256 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4259 DOS-style file names with drive letters are now fully supported by
4262 It is now possible to debug DJGPP programs that switch their working
4263 directory. It is also possible to rerun the debuggee any number of
4264 times without restarting GDB; thus, you can use the same setup,
4265 breakpoints, etc. for many debugging sessions.
4267 * New native configurations
4269 ARM GNU/Linux arm*-*-linux*
4270 PowerPC GNU/Linux powerpc-*-linux*
4274 Motorola MCore mcore-*-*
4275 x86 VxWorks i[3456]86-*-vxworks*
4276 PowerPC VxWorks powerpc-*-vxworks*
4277 TI TMS320C80 tic80-*-*
4279 * OBSOLETE configurations
4281 Altos 3068 m68*-altos-*
4282 Convex c1-*-*, c2-*-*
4284 ARM RISCix arm-*-* (as host)
4287 Configurations that have been declared obsolete will be commented out,
4288 but the code will be left in place. If there is no activity to revive
4289 these configurations before the next release of GDB, the sources will
4290 be permanently REMOVED.
4292 * Gould support removed
4294 Support for the Gould PowerNode and NP1 has been removed.
4296 * New features for SVR4
4298 On SVR4 native platforms (such as Solaris), if you attach to a process
4299 without first loading a symbol file, GDB will now attempt to locate and
4300 load symbols from the running process's executable file.
4302 * Many C++ enhancements
4304 C++ support has been greatly improved. Overload resolution now works properly
4305 in almost all cases. RTTI support is on the way.
4307 * Remote targets can connect to a sub-program
4309 A popen(3) style serial-device has been added. This device starts a
4310 sub-process (such as a stand-alone simulator) and then communicates
4311 with that. The sub-program to run is specified using the syntax
4312 ``|<program> <args>'' vis:
4314 (gdb) set remotedebug 1
4315 (gdb) target extended-remote |mn10300-elf-sim program-args
4317 * MIPS 64 remote protocol
4319 A long standing bug in the mips64 remote protocol where by GDB
4320 expected certain 32 bit registers (ex SR) to be transfered as 32
4321 instead of 64 bits has been fixed.
4323 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4324 added to provide backward compatibility with older versions of GDB.
4326 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4328 The command ``set remotebinarydownload'' command has been replaced by
4329 ``set remote X-packet''. Other commands in ``set remote'' family
4330 include ``set remote P-packet''.
4332 * Breakpoint commands accept ranges.
4334 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4335 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4336 ``tracepoint passcount'' also accepts a range of tracepoints.
4338 * ``apropos'' command added.
4340 The ``apropos'' command searches through command names and
4341 documentation strings, printing out matches, making it much easier to
4342 try to find a command that does what you are looking for.
4346 A new machine oriented interface (MI) has been added to GDB. This
4347 interface is designed for debug environments running GDB as a separate
4348 process. This is part of the long term libGDB project. See the
4349 "GDB/MI" chapter of the GDB manual for further information. It can be
4350 enabled by configuring with:
4352 .../configure --enable-gdbmi
4354 *** Changes in GDB-4.18:
4356 * New native configurations
4358 HP-UX 10.20 hppa*-*-hpux10.20
4359 HP-UX 11.x hppa*-*-hpux11.0*
4360 M68K GNU/Linux m68*-*-linux*
4364 Fujitsu FR30 fr30-*-elf*
4365 Intel StrongARM strongarm-*-*
4366 Mitsubishi D30V d30v-*-*
4368 * OBSOLETE configurations
4370 Gould PowerNode, NP1 np1-*-*, pn-*-*
4372 Configurations that have been declared obsolete will be commented out,
4373 but the code will be left in place. If there is no activity to revive
4374 these configurations before the next release of GDB, the sources will
4375 be permanently REMOVED.
4379 As a compatibility experiment, GDB's source files buildsym.h and
4380 buildsym.c have been converted to pure standard C, no longer
4381 containing any K&R compatibility code. We believe that all systems in
4382 use today either come with a standard C compiler, or have a GCC port
4383 available. If this is not true, please report the affected
4384 configuration to bug-gdb@gnu.org immediately. See the README file for
4385 information about getting a standard C compiler if you don't have one
4390 GDB now uses readline 2.2.
4392 * set extension-language
4394 You can now control the mapping between filename extensions and source
4395 languages by using the `set extension-language' command. For instance,
4396 you can ask GDB to treat .c files as C++ by saying
4397 set extension-language .c c++
4398 The command `info extensions' lists all of the recognized extensions
4399 and their associated languages.
4401 * Setting processor type for PowerPC and RS/6000
4403 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4404 you can use the `set processor' command to specify what variant of the
4405 PowerPC family you are debugging. The command
4409 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4410 following PowerPC and RS6000 variants:
4412 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4413 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4415 403GC IBM PowerPC 403GC
4416 505 Motorola PowerPC 505
4417 860 Motorola PowerPC 860 or 850
4418 601 Motorola PowerPC 601
4419 602 Motorola PowerPC 602
4420 603 Motorola/IBM PowerPC 603 or 603e
4421 604 Motorola PowerPC 604 or 604e
4422 750 Motorola/IBM PowerPC 750 or 750
4424 At the moment, this command just tells GDB what to name the
4425 special-purpose processor registers. Since almost all the affected
4426 registers are inaccessible to user-level programs, this command is
4427 only useful for remote debugging in its present form.
4431 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4432 more extensive support for HP-UX. Added features include shared
4433 library support, kernel threads and hardware watchpoints for 11.00,
4434 support for HP's ANSI C and C++ compilers, and a compatibility mode
4435 for xdb and dbx commands.
4439 HP's donation includes the new concept of catchpoints, which is a
4440 generalization of the old catch command. On HP-UX, it is now possible
4441 to catch exec, fork, and vfork, as well as library loading.
4443 This means that the existing catch command has changed; its first
4444 argument now specifies the type of catch to be set up. See the
4445 output of "help catch" for a list of catchpoint types.
4447 * Debugging across forks
4449 On HP-UX, you can choose which process to debug when a fork() happens
4454 HP has donated a curses-based terminal user interface (TUI). To get
4455 it, build with --enable-tui. Although this can be enabled for any
4456 configuration, at present it only works for native HP debugging.
4458 * GDB remote protocol additions
4460 A new protocol packet 'X' that writes binary data is now available.
4461 Default behavior is to try 'X', then drop back to 'M' if the stub
4462 fails to respond. The settable variable `remotebinarydownload'
4463 allows explicit control over the use of 'X'.
4465 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4466 full 64-bit address. The command
4468 set remoteaddresssize 32
4470 can be used to revert to the old behaviour. For existing remote stubs
4471 the change should not be noticed, as the additional address information
4474 In order to assist in debugging stubs, you may use the maintenance
4475 command `packet' to send any text string to the stub. For instance,
4477 maint packet heythere
4479 sends the packet "$heythere#<checksum>". Note that it is very easy to
4480 disrupt a debugging session by sending the wrong packet at the wrong
4483 The compare-sections command allows you to compare section data on the
4484 target to what is in the executable file without uploading or
4485 downloading, by comparing CRC checksums.
4487 * Tracing can collect general expressions
4489 You may now collect general expressions at tracepoints. This requires
4490 further additions to the target-side stub; see tracepoint.c and
4491 doc/agentexpr.texi for further details.
4493 * mask-address variable for Mips
4495 For Mips targets, you may control the zeroing of the upper 32 bits of
4496 a 64-bit address by entering `set mask-address on'. This is mainly
4497 of interest to users of embedded R4xxx and R5xxx processors.
4499 * Higher serial baud rates
4501 GDB's serial code now allows you to specify baud rates 57600, 115200,
4502 230400, and 460800 baud. (Note that your host system may not be able
4503 to achieve all of these rates.)
4507 The i960 configuration now includes an initial implementation of a
4508 builtin simulator, contributed by Jim Wilson.
4511 *** Changes in GDB-4.17:
4513 * New native configurations
4515 Alpha GNU/Linux alpha*-*-linux*
4516 Unixware 2.x i[3456]86-unixware2*
4517 Irix 6.x mips*-sgi-irix6*
4518 PowerPC GNU/Linux powerpc-*-linux*
4519 PowerPC Solaris powerpcle-*-solaris*
4520 Sparc GNU/Linux sparc-*-linux*
4521 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4525 Argonaut Risc Chip (ARC) arc-*-*
4526 Hitachi H8/300S h8300*-*-*
4527 Matsushita MN10200 w/simulator mn10200-*-*
4528 Matsushita MN10300 w/simulator mn10300-*-*
4529 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4530 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4531 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4532 Mitsubishi D10V w/simulator d10v-*-*
4533 Mitsubishi M32R/D w/simulator m32r-*-elf*
4534 Tsqware Sparclet sparclet-*-*
4535 NEC V850 w/simulator v850-*-*
4537 * New debugging protocols
4539 ARM with RDI protocol arm*-*-*
4540 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4541 DDB and LSI variants of PMON protocol mips*-*-*
4542 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4543 PowerPC with SDS protocol powerpc{,le}-*-eabi
4544 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4548 All configurations can now understand and use the DWARF 2 debugging
4549 format. The choice is automatic, if the symbol file contains DWARF 2
4554 GDB now includes basic Java language support. This support is
4555 only useful with Java compilers that produce native machine code.
4557 * solib-absolute-prefix and solib-search-path
4559 For SunOS and SVR4 shared libraries, you may now set the prefix for
4560 loading absolute shared library symbol files, and the search path for
4561 locating non-absolute shared library symbol files.
4563 * Live range splitting
4565 GDB can now effectively debug code for which GCC has performed live
4566 range splitting as part of its optimization. See gdb/doc/LRS for
4567 more details on the expected format of the stabs information.
4571 GDB's support for the GNU Hurd, including thread debugging, has been
4572 updated to work with current versions of the Hurd.
4576 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4577 instruction set. ARM GDB automatically detects when Thumb
4578 instructions are in use, and adjusts disassembly and backtracing
4583 GDB's MIPS target configurations now handle the MIP16 16-bit
4588 GDB now includes support for overlays; if an executable has been
4589 linked such that multiple sections are based at the same address, GDB
4590 will decide which section to use for symbolic info. You can choose to
4591 control the decision manually, using overlay commands, or implement
4592 additional target-side support and use "overlay load-target" to bring
4593 in the overlay mapping. Do "help overlay" for more detail.
4597 The command "info symbol <address>" displays information about
4598 the symbol at the specified address.
4602 The standard remote protocol now includes an extension that allows
4603 asynchronous collection and display of trace data. This requires
4604 extensive support in the target-side debugging stub. Tracing mode
4605 includes a new interaction mode in GDB and new commands: see the
4606 file tracepoint.c for more details.
4610 Configurations for embedded MIPS now include a simulator contributed
4611 by Cygnus Solutions. The simulator supports the instruction sets
4612 of most MIPS variants.
4616 Sparc configurations may now include the ERC32 simulator contributed
4617 by the European Space Agency. The simulator is not built into
4618 Sparc targets by default; configure with --enable-sim to include it.
4622 For target configurations that may include multiple variants of a
4623 basic architecture (such as MIPS and SH), you may now set the
4624 architecture explicitly. "set arch" sets, "info arch" lists
4625 the possible architectures.
4627 *** Changes in GDB-4.16:
4629 * New native configurations
4631 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4632 M68K NetBSD m68k-*-netbsd*
4633 PowerPC AIX 4.x powerpc-*-aix*
4634 PowerPC MacOS powerpc-*-macos*
4635 PowerPC Windows NT powerpcle-*-cygwin32
4636 RS/6000 AIX 4.x rs6000-*-aix4*
4640 ARM with RDP protocol arm-*-*
4641 I960 with MON960 i960-*-coff
4642 MIPS VxWorks mips*-*-vxworks*
4643 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4644 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4646 Matra Sparclet sparclet-*-*
4650 The powerpc-eabi configuration now includes the PSIM simulator,
4651 contributed by Andrew Cagney, with assistance from Mike Meissner.
4652 PSIM is a very elaborate model of the PowerPC, including not only
4653 basic instruction set execution, but also details of execution unit
4654 performance and I/O hardware. See sim/ppc/README for more details.
4658 GDB now works with Solaris 2.5.
4660 * Windows 95/NT native
4662 GDB will now work as a native debugger on Windows 95 and Windows NT.
4663 To build it from source, you must use the "gnu-win32" environment,
4664 which uses a DLL to emulate enough of Unix to run the GNU tools.
4665 Further information, binaries, and sources are available at
4666 ftp.cygnus.com, under pub/gnu-win32.
4668 * dont-repeat command
4670 If a user-defined command includes the command `dont-repeat', then the
4671 command will not be repeated if the user just types return. This is
4672 useful if the command is time-consuming to run, so that accidental
4673 extra keystrokes don't run the same command many times.
4675 * Send break instead of ^C
4677 The standard remote protocol now includes an option to send a break
4678 rather than a ^C to the target in order to interrupt it. By default,
4679 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4681 * Remote protocol timeout
4683 The standard remote protocol includes a new variable `remotetimeout'
4684 that allows you to set the number of seconds before GDB gives up trying
4685 to read from the target. The default value is 2.
4687 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4689 By default GDB will automatically keep track of objects as they are
4690 loaded and unloaded by the dynamic linker. By using the command `set
4691 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4692 when shared library events occur, thus allowing you to set breakpoints
4693 in shared libraries which are explicitly loaded by the inferior.
4695 Note this feature does not work on hpux8. On hpux9 you must link
4696 /usr/lib/end.o into your program. This feature should work
4697 automatically on hpux10.
4699 * Irix 5.x hardware watchpoint support
4701 Irix 5 configurations now support the use of hardware watchpoints.
4703 * Mips protocol "SYN garbage limit"
4705 When debugging a Mips target using the `target mips' protocol, you
4706 may set the number of characters that GDB will ignore by setting
4707 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4708 every character. The default value is 1050.
4710 * Recording and replaying remote debug sessions
4712 If you set `remotelogfile' to the name of a file, gdb will write to it
4713 a recording of a remote debug session. This recording may then be
4714 replayed back to gdb using "gdbreplay". See gdbserver/README for
4715 details. This is useful when you have a problem with GDB while doing
4716 remote debugging; you can make a recording of the session and send it
4717 to someone else, who can then recreate the problem.
4719 * Speedups for remote debugging
4721 GDB includes speedups for downloading and stepping MIPS systems using
4722 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4723 and more efficient S-record downloading.
4725 * Memory use reductions and statistics collection
4727 GDB now uses less memory and reports statistics about memory usage.
4728 Try the `maint print statistics' command, for example.
4730 *** Changes in GDB-4.15:
4732 * Psymtabs for XCOFF
4734 The symbol reader for AIX GDB now uses partial symbol tables. This
4735 can greatly improve startup time, especially for large executables.
4737 * Remote targets use caching
4739 Remote targets now use a data cache to speed up communication with the
4740 remote side. The data cache could lead to incorrect results because
4741 it doesn't know about volatile variables, thus making it impossible to
4742 debug targets which use memory mapped I/O devices. `set remotecache
4743 off' turns the the data cache off.
4745 * Remote targets may have threads
4747 The standard remote protocol now includes support for multiple threads
4748 in the target system, using new protocol commands 'H' and 'T'. See
4749 gdb/remote.c for details.
4753 If GDB is configured with `--enable-netrom', then it will include
4754 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4755 acts as though it is a bank of ROM on the target board, but you can
4756 write into it over the network. GDB's support consists only of
4757 support for fast loading into the emulated ROM; to debug, you must use
4758 another protocol, such as standard remote protocol. The usual
4759 sequence is something like
4761 target nrom <netrom-hostname>
4763 target remote <netrom-hostname>:1235
4767 GDB now includes support for the Apple Macintosh, as a host only. It
4768 may be run as either an MPW tool or as a standalone application, and
4769 it can debug through the serial port. All the usual GDB commands are
4770 available, but to the target command, you must supply "serial" as the
4771 device type instead of "/dev/ttyXX". See mpw-README in the main
4772 directory for more information on how to build. The MPW configuration
4773 scripts */mpw-config.in support only a few targets, and only the
4774 mips-idt-ecoff target has been tested.
4778 GDB configuration now uses autoconf. This is not user-visible,
4779 but does simplify configuration and building.
4783 GDB now supports hpux10.
4785 *** Changes in GDB-4.14:
4787 * New native configurations
4789 x86 FreeBSD i[345]86-*-freebsd
4790 x86 NetBSD i[345]86-*-netbsd
4791 NS32k NetBSD ns32k-*-netbsd
4792 Sparc NetBSD sparc-*-netbsd
4796 A29K VxWorks a29k-*-vxworks
4797 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4798 CPU32 EST-300 emulator m68*-*-est*
4799 PowerPC ELF powerpc-*-elf
4802 * Alpha OSF/1 support for procfs
4804 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4805 possible to attach to running processes. As the mounting of the /proc
4806 filesystem is optional on the Alpha, GDB automatically determines
4807 the availability of /proc during startup. This can lead to problems
4808 if /proc is unmounted after GDB has been started.
4810 * Arguments to user-defined commands
4812 User commands may accept up to 10 arguments separated by whitespace.
4813 Arguments are accessed within the user command via $arg0..$arg9. A
4816 print $arg0 + $arg1 + $arg2
4818 To execute the command use:
4821 Defines the command "adder" which prints the sum of its three arguments.
4822 Note the arguments are text substitutions, so they may reference variables,
4823 use complex expressions, or even perform inferior function calls.
4825 * New `if' and `while' commands
4827 This makes it possible to write more sophisticated user-defined
4828 commands. Both commands take a single argument, which is the
4829 expression to evaluate, and must be followed by the commands to
4830 execute, one per line, if the expression is nonzero, the list being
4831 terminated by the word `end'. The `if' command list may include an
4832 `else' word, which causes the following commands to be executed only
4833 if the expression is zero.
4835 * Fortran source language mode
4837 GDB now includes partial support for Fortran 77. It will recognize
4838 Fortran programs and can evaluate a subset of Fortran expressions, but
4839 variables and functions may not be handled correctly. GDB will work
4840 with G77, but does not yet know much about symbols emitted by other
4843 * Better HPUX support
4845 Most debugging facilities now work on dynamic executables for HPPAs
4846 running hpux9 or later. You can attach to running dynamically linked
4847 processes, but by default the dynamic libraries will be read-only, so
4848 for instance you won't be able to put breakpoints in them. To change
4849 that behavior do the following before running the program:
4855 This will cause the libraries to be mapped private and read-write.
4856 To revert to the normal behavior, do this:
4862 You cannot set breakpoints or examine data in the library until after
4863 the library is loaded if the function/data symbols do not have
4866 GDB can now also read debug symbols produced by the HP C compiler on
4867 HPPAs (sorry, no C++, Fortran or 68k support).
4869 * Target byte order now dynamically selectable
4871 You can choose which byte order to use with a target system, via the
4872 commands "set endian big" and "set endian little", and you can see the
4873 current setting by using "show endian". You can also give the command
4874 "set endian auto", in which case GDB will use the byte order
4875 associated with the executable. Currently, only embedded MIPS
4876 configurations support dynamic selection of target byte order.
4878 * New DOS host serial code
4880 This version uses DPMI interrupts to handle buffered I/O, so you
4881 no longer need to run asynctsr when debugging boards connected to
4884 *** Changes in GDB-4.13:
4886 * New "complete" command
4888 This lists all the possible completions for the rest of the line, if it
4889 were to be given as a command itself. This is intended for use by emacs.
4891 * Trailing space optional in prompt
4893 "set prompt" no longer adds a space for you after the prompt you set. This
4894 allows you to set a prompt which ends in a space or one that does not.
4896 * Breakpoint hit counts
4898 "info break" now displays a count of the number of times the breakpoint
4899 has been hit. This is especially useful in conjunction with "ignore"; you
4900 can ignore a large number of breakpoint hits, look at the breakpoint info
4901 to see how many times the breakpoint was hit, then run again, ignoring one
4902 less than that number, and this will get you quickly to the last hit of
4905 * Ability to stop printing at NULL character
4907 "set print null-stop" will cause GDB to stop printing the characters of
4908 an array when the first NULL is encountered. This is useful when large
4909 arrays actually contain only short strings.
4911 * Shared library breakpoints
4913 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4914 breakpoints in shared libraries before the executable is run.
4916 * Hardware watchpoints
4918 There is a new hardware breakpoint for the watch command for sparclite
4919 targets. See gdb/sparclite/hw_breakpoint.note.
4921 Hardware watchpoints are also now supported under GNU/Linux.
4925 Annotations have been added. These are for use with graphical interfaces,
4926 and are still experimental. Currently only gdba.el uses these.
4928 * Improved Irix 5 support
4930 GDB now works properly with Irix 5.2.
4932 * Improved HPPA support
4934 GDB now works properly with the latest GCC and GAS.
4936 * New native configurations
4938 Sequent PTX4 i[34]86-sequent-ptx4
4939 HPPA running OSF/1 hppa*-*-osf*
4940 Atari TT running SVR4 m68*-*-sysv4*
4941 RS/6000 LynxOS rs6000-*-lynxos*
4945 OS/9000 i[34]86-*-os9k
4946 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4949 * Hitachi SH7000 and E7000-PC ICE support
4951 There is now support for communicating with the Hitachi E7000-PC ICE.
4952 This is available automatically when GDB is configured for the SH.
4956 As usual, a variety of small fixes and improvements, both generic
4957 and configuration-specific. See the ChangeLog for more detail.
4959 *** Changes in GDB-4.12:
4961 * Irix 5 is now supported
4965 GDB-4.12 on the HPPA has a number of changes which make it unable
4966 to debug the output from the currently released versions of GCC and
4967 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4968 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4969 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4972 *** Changes in GDB-4.11:
4974 * User visible changes:
4978 The "set remotedebug" option is now consistent between the mips remote
4979 target, remote targets using the gdb-specific protocol, UDI (AMD's
4980 debug protocol for the 29k) and the 88k bug monitor. It is now an
4981 integer specifying a debug level (normally 0 or 1, but 2 means more
4982 debugging info for the mips target).
4984 * DEC Alpha native support
4986 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4987 debug info, but GDB works fairly well with the DEC compiler and should
4988 work with a future GCC release. See the README file for a few
4989 Alpha-specific notes.
4991 * Preliminary thread implementation
4993 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4995 * LynxOS native and target support for 386
4997 This release has been hosted on LynxOS 2.2, and also can be configured
4998 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5001 * Improvements in C++ mangling/demangling.
5003 This release has much better g++ debugging, specifically in name
5004 mangling/demangling, virtual function calls, print virtual table,
5005 call methods, ...etc.
5007 *** Changes in GDB-4.10:
5009 * User visible changes:
5011 Remote debugging using the GDB-specific (`target remote') protocol now
5012 supports the `load' command. This is only useful if you have some
5013 other way of getting the stub to the target system, and you can put it
5014 somewhere in memory where it won't get clobbered by the download.
5016 Filename completion now works.
5018 When run under emacs mode, the "info line" command now causes the
5019 arrow to point to the line specified. Also, "info line" prints
5020 addresses in symbolic form (as well as hex).
5022 All vxworks based targets now support a user settable option, called
5023 vxworks-timeout. This option represents the number of seconds gdb
5024 should wait for responses to rpc's. You might want to use this if
5025 your vxworks target is, perhaps, a slow software simulator or happens
5026 to be on the far side of a thin network line.
5030 This release contains support for using a DEC alpha as a GDB host for
5031 cross debugging. Native alpha debugging is not supported yet.
5034 *** Changes in GDB-4.9:
5038 This is the first GDB release which is accompanied by a matching testsuite.
5039 The testsuite requires installation of dejagnu, which should be available
5040 via ftp from most sites that carry GNU software.
5044 'Cfront' style demangling has had its name changed to 'ARM' style, to
5045 emphasize that it was written from the specifications in the C++ Annotated
5046 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5047 disclaimers, it still generated too much confusion with users attempting to
5048 use gdb with AT&T cfront.
5052 GDB now uses a standard remote interface to a simulator library.
5053 So far, the library contains simulators for the Zilog Z8001/2, the
5054 Hitachi H8/300, H8/500 and Super-H.
5056 * New targets supported
5058 H8/300 simulator h8300-hitachi-hms or h8300hms
5059 H8/500 simulator h8500-hitachi-hms or h8500hms
5060 SH simulator sh-hitachi-hms or sh
5061 Z8000 simulator z8k-zilog-none or z8ksim
5062 IDT MIPS board over serial line mips-idt-ecoff
5064 Cross-debugging to GO32 targets is supported. It requires a custom
5065 version of the i386-stub.c module which is integrated with the
5066 GO32 memory extender.
5068 * New remote protocols
5070 MIPS remote debugging protocol.
5072 * New source languages supported
5074 This version includes preliminary support for Chill, a Pascal like language
5075 used by telecommunications companies. Chill support is also being integrated
5076 into the GNU compiler, but we don't know when it will be publically available.
5079 *** Changes in GDB-4.8:
5081 * HP Precision Architecture supported
5083 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5084 version of this support was available as a set of patches from the
5085 University of Utah. GDB does not support debugging of programs
5086 compiled with the HP compiler, because HP will not document their file
5087 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5088 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5090 Many problems in the preliminary version have been fixed.
5092 * Faster and better demangling
5094 We have improved template demangling and fixed numerous bugs in the GNU style
5095 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5096 character types (wchar_t) are now supported. Demangling of each symbol is now
5097 only done once, and is cached when the symbol table for a file is read in.
5098 This results in a small increase in memory usage for C programs, a moderate
5099 increase in memory usage for C++ programs, and a fantastic speedup in
5102 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5103 from the specifications in the Annotated Reference Manual, which AT&T's
5104 compiler does not actually implement.
5106 * G++ multiple inheritance compiler problem
5108 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5109 inheritance lattices was reworked to properly discover ambiguities. We
5110 recently found an example which causes this new algorithm to fail in a
5111 very subtle way, producing bad debug information for those classes.
5112 The file 'gcc.patch' (in this directory) can be applied to gcc to
5113 circumvent the problem. A future GCC release will contain a complete
5116 The previous G++ debug info problem (mentioned below for the gdb-4.7
5117 release) is fixed in gcc version 2.3.2.
5119 * Improved configure script
5121 The `configure' script will now attempt to guess your system type if
5122 you don't supply a host system type. The old scheme of supplying a
5123 host system triplet is preferable over using this. All the magic is
5124 done in the new `config.guess' script. Examine it for details.
5126 We have also brought our configure script much more in line with the FSF's
5127 version. It now supports the --with-xxx options. In particular,
5128 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5129 The resulting GDB will not be able to read arbitrary object file formats --
5130 only the format ``expected'' to be used on the configured target system.
5131 We hope to make this the default in a future release.
5133 * Documentation improvements
5135 There's new internal documentation on how to modify GDB, and how to
5136 produce clean changes to the code. We implore people to read it
5137 before submitting changes.
5139 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5140 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5141 `info' files are also provided. To build `info' files from scratch,
5142 you will need the latest `makeinfo' release, which will be available in
5143 a future texinfo-X.Y release.
5145 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5146 We're not sure exactly which versions have this problem, but it has
5147 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5148 or better. If that isn't possible, there is a patch in
5149 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5150 around this problem.
5154 GDB now supports array constants that can be used in expressions typed in by
5155 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5156 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5159 The new directory `gdb/sparclite' contains a program that demonstrates
5160 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5162 * New native hosts supported
5164 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5165 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5167 * New targets supported
5169 AMD 29k family via UDI a29k-amd-udi or udi29k
5171 * New file formats supported
5173 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5174 HPUX core files, and SCO 3.2v2 core files.
5178 Attaching to processes now works again; thanks for the many bug reports.
5180 We have also stomped on a bunch of core dumps caused by
5181 printf_filtered("%s") problems.
5183 We eliminated a copyright problem on the rpc and ptrace header files
5184 for VxWorks, which was discovered at the last minute during the 4.7
5185 release. You should now be able to build a VxWorks GDB.
5187 You can now interrupt gdb while an attached process is running. This
5188 will cause the attached process to stop, and give control back to GDB.
5190 We fixed problems caused by using too many file descriptors
5191 for reading symbols from object files and libraries. This was
5192 especially a problem for programs that used many (~100) shared
5195 The `step' command now only enters a subroutine if there is line number
5196 information for the subroutine. Otherwise it acts like the `next'
5197 command. Previously, `step' would enter subroutines if there was
5198 any debugging information about the routine. This avoids problems
5199 when using `cc -g1' on MIPS machines.
5201 * Internal improvements
5203 GDB's internal interfaces have been improved to make it easier to support
5204 debugging of multiple languages in the future.
5206 GDB now uses a common structure for symbol information internally.
5207 Minimal symbols (derived from linkage symbols in object files), partial
5208 symbols (from a quick scan of debug information), and full symbols
5209 contain a common subset of information, making it easier to write
5210 shared code that handles any of them.
5212 * New command line options
5214 We now accept --silent as an alias for --quiet.
5218 The memory-mapped-malloc library is now licensed under the GNU Library
5219 General Public License.
5221 *** Changes in GDB-4.7:
5223 * Host/native/target split
5225 GDB has had some major internal surgery to untangle the support for
5226 hosts and remote targets. Now, when you configure GDB for a remote
5227 target, it will no longer load in all of the support for debugging
5228 local programs on the host. When fully completed and tested, this will
5229 ensure that arbitrary host/target combinations are possible.
5231 The primary conceptual shift is to separate the non-portable code in
5232 GDB into three categories. Host specific code is required any time GDB
5233 is compiled on that host, regardless of the target. Target specific
5234 code relates to the peculiarities of the target, but can be compiled on
5235 any host. Native specific code is everything else: it can only be
5236 built when the host and target are the same system. Child process
5237 handling and core file support are two common `native' examples.
5239 GDB's use of /proc for controlling Unix child processes is now cleaner.
5240 It has been split out into a single module under the `target_ops' vector,
5241 plus two native-dependent functions for each system that uses /proc.
5243 * New hosts supported
5245 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5246 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5247 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5249 * New targets supported
5251 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5252 68030 and CPU32 m68030-*-*, m68332-*-*
5254 * New native hosts supported
5256 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5257 (386bsd is not well tested yet)
5258 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5260 * New file formats supported
5262 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5263 supports reading of `a.out.adobe' object files, which are an a.out
5264 format extended with minimal information about multiple sections.
5268 `show copying' is the same as the old `info copying'.
5269 `show warranty' is the same as `info warrantee'.
5270 These were renamed for consistency. The old commands continue to work.
5272 `info handle' is a new alias for `info signals'.
5274 You can now define pre-command hooks, which attach arbitrary command
5275 scripts to any command. The commands in the hook will be executed
5276 prior to the user's command. You can also create a hook which will be
5277 executed whenever the program stops. See gdb.texinfo.
5281 We now deal with Cfront style name mangling, and can even extract type
5282 info from mangled symbols. GDB can automatically figure out which
5283 symbol mangling style your C++ compiler uses.
5285 Calling of methods and virtual functions has been improved as well.
5289 The crash that occured when debugging Sun Ansi-C compiled binaries is
5290 fixed. This was due to mishandling of the extra N_SO stabs output
5293 We also finally got Ultrix 4.2 running in house, and fixed core file
5294 support, with help from a dozen people on the net.
5296 John M. Farrell discovered that the reason that single-stepping was so
5297 slow on all of the Mips based platforms (primarily SGI and DEC) was
5298 that we were trying to demangle and lookup a symbol used for internal
5299 purposes on every instruction that was being stepped through. Changing
5300 the name of that symbol so that it couldn't be mistaken for a C++
5301 mangled symbol sped things up a great deal.
5303 Rich Pixley sped up symbol lookups in general by getting much smarter
5304 about when C++ symbol mangling is necessary. This should make symbol
5305 completion (TAB on the command line) much faster. It's not as fast as
5306 we'd like, but it's significantly faster than gdb-4.6.
5310 A new user controllable variable 'call_scratch_address' can
5311 specify the location of a scratch area to be used when GDB
5312 calls a function in the target. This is necessary because the
5313 usual method of putting the scratch area on the stack does not work
5314 in systems that have separate instruction and data spaces.
5316 We integrated changes to support the 29k UDI (Universal Debugger
5317 Interface), but discovered at the last minute that we didn't have all
5318 of the appropriate copyright paperwork. We are working with AMD to
5319 resolve this, and hope to have it available soon.
5323 We have sped up the remote serial line protocol, especially for targets
5324 with lots of registers. It now supports a new `expedited status' ('T')
5325 message which can be used in place of the existing 'S' status message.
5326 This allows the remote stub to send only the registers that GDB
5327 needs to make a quick decision about single-stepping or conditional
5328 breakpoints, eliminating the need to fetch the entire register set for
5329 each instruction being stepped through.
5331 The GDB remote serial protocol now implements a write-through cache for
5332 registers, only re-reading the registers if the target has run.
5334 There is also a new remote serial stub for SPARC processors. You can
5335 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5336 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5337 processor with a serial port.
5341 Configure.in files have become much easier to read and modify. A new
5342 `table driven' format makes it more obvious what configurations are
5343 supported, and what files each one uses.
5347 There is a new opcodes library which will eventually contain all of the
5348 disassembly routines and opcode tables. At present, it only contains
5349 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5350 disassembler (binutils/objdump) to share these routines.
5352 The libiberty library is now copylefted under the GNU Library General
5353 Public License. This allows more liberal use, and was done so libg++
5354 can use it. This makes no difference to GDB, since the Library License
5355 grants all the rights from the General Public License.
5359 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5360 reference to the stabs symbol info used by the debugger. It is (as far
5361 as we know) the only published document on this fascinating topic. We
5362 encourage you to read it, compare it to the stabs information on your
5363 system, and send improvements on the document in general (to
5364 bug-gdb@prep.ai.mit.edu).
5366 And, of course, many bugs have been fixed.
5369 *** Changes in GDB-4.6:
5371 * Better support for C++ function names
5373 GDB now accepts as input the "demangled form" of C++ overloaded function
5374 names and member function names, and can do command completion on such names
5375 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5376 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5377 Make use of command completion, it is your friend.
5379 GDB also now accepts a variety of C++ mangled symbol formats. They are
5380 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5381 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5382 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5383 for the list of formats.
5385 * G++ symbol mangling problem
5387 Recent versions of gcc have a bug in how they emit debugging information for
5388 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5389 directory) can be applied to gcc to fix the problem. Alternatively, if you
5390 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5391 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5392 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5395 * New 'maintenance' command
5397 All of the commands related to hacking GDB internals have been moved out of
5398 the main command set, and now live behind the 'maintenance' command. This
5399 can also be abbreviated as 'mt'. The following changes were made:
5401 dump-me -> maintenance dump-me
5402 info all-breakpoints -> maintenance info breakpoints
5403 printmsyms -> maintenance print msyms
5404 printobjfiles -> maintenance print objfiles
5405 printpsyms -> maintenance print psymbols
5406 printsyms -> maintenance print symbols
5408 The following commands are new:
5410 maintenance demangle Call internal GDB demangler routine to
5411 demangle a C++ link name and prints the result.
5412 maintenance print type Print a type chain for a given symbol
5414 * Change to .gdbinit file processing
5416 We now read the $HOME/.gdbinit file before processing the argv arguments
5417 (e.g. reading symbol files or core files). This allows global parameters to
5418 be set, which will apply during the symbol reading. The ./.gdbinit is still
5419 read after argv processing.
5421 * New hosts supported
5423 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5425 GNU/Linux support i386-unknown-linux or linux
5427 We are also including code to support the HP/PA running BSD and HPUX. This
5428 is almost guaranteed not to work, as we didn't have time to test or build it
5429 for this release. We are including it so that the more adventurous (or
5430 masochistic) of you can play with it. We also had major problems with the
5431 fact that the compiler that we got from HP doesn't support the -g option.
5434 * New targets supported
5436 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5438 * More smarts about finding #include files
5440 GDB now remembers the compilation directory for all include files, and for
5441 all files from which C is generated (like yacc and lex sources). This
5442 greatly improves GDB's ability to find yacc/lex sources, and include files,
5443 especially if you are debugging your program from a directory different from
5444 the one that contains your sources.
5446 We also fixed a bug which caused difficulty with listing and setting
5447 breakpoints in include files which contain C code. (In the past, you had to
5448 try twice in order to list an include file that you hadn't looked at before.)
5450 * Interesting infernals change
5452 GDB now deals with arbitrary numbers of sections, where the symbols for each
5453 section must be relocated relative to that section's landing place in the
5454 target's address space. This work was needed to support ELF with embedded
5455 stabs used by Solaris-2.0.
5457 * Bug fixes (of course!)
5459 There have been loads of fixes for the following things:
5460 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5461 i960, stabs, DOS(GO32), procfs, etc...
5463 See the ChangeLog for details.
5465 *** Changes in GDB-4.5:
5467 * New machines supported (host and target)
5469 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5471 SGI Irix-4.x mips-sgi-irix4 or iris4
5473 * New malloc package
5475 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5476 Mmalloc is capable of handling mutiple heaps of memory. It is also
5477 capable of saving a heap to a file, and then mapping it back in later.
5478 This can be used to greatly speedup the startup of GDB by using a
5479 pre-parsed symbol table which lives in a mmalloc managed heap. For
5480 more details, please read mmalloc/mmalloc.texi.
5484 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5485 'help info proc' for details.
5487 * MIPS ecoff symbol table format
5489 The code that reads MIPS symbol table format is now supported on all hosts.
5490 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5493 * File name changes for MS-DOS
5495 Many files in the config directories have been renamed to make it easier to
5496 support GDB on MS-DOSe systems (which have very restrictive file name
5497 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5498 environment) is close to working but has some remaining problems. Note
5499 that debugging of DOS programs is not supported, due to limitations
5500 in the ``operating system'', but it can be used to host cross-debugging.
5502 * Cross byte order fixes
5504 Many fixes have been made to support cross debugging of Sparc and MIPS
5505 targets from hosts whose byte order differs.
5507 * New -mapped and -readnow options
5509 If memory-mapped files are available on your system through the 'mmap'
5510 system call, you can use the -mapped option on the `file' or
5511 `symbol-file' commands to cause GDB to write the symbols from your
5512 program into a reusable file. If the program you are debugging is
5513 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5514 Future GDB debugging sessions will notice the presence of this file,
5515 and will quickly map in symbol information from it, rather than reading
5516 the symbol table from the executable program. Using the '-mapped'
5517 option in a GDB `file' or `symbol-file' command has the same effect as
5518 starting GDB with the '-mapped' command-line option.
5520 You can cause GDB to read the entire symbol table immediately by using
5521 the '-readnow' option with any of the commands that load symbol table
5522 information (or on the GDB command line). This makes the command
5523 slower, but makes future operations faster.
5525 The -mapped and -readnow options are typically combined in order to
5526 build a `fred.syms' file that contains complete symbol information.
5527 A simple GDB invocation to do nothing but build a `.syms' file for future
5530 gdb -batch -nx -mapped -readnow programname
5532 The `.syms' file is specific to the host machine on which GDB is run.
5533 It holds an exact image of GDB's internal symbol table. It cannot be
5534 shared across multiple host platforms.
5536 * longjmp() handling
5538 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5539 siglongjmp() without losing control. This feature has not yet been ported to
5540 all systems. It currently works on many 386 platforms, all MIPS-based
5541 platforms (SGI, DECstation, etc), and Sun3/4.
5545 Preliminary work has been put in to support the new Solaris OS from Sun. At
5546 this time, it can control and debug processes, but it is not capable of
5551 As always, many many bug fixes. The major areas were with g++, and mipsread.
5552 People using the MIPS-based platforms should experience fewer mysterious
5553 crashes and trashed symbol tables.
5555 *** Changes in GDB-4.4:
5557 * New machines supported (host and target)
5559 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5561 BSD Reno on Vax vax-dec-bsd
5562 Ultrix on Vax vax-dec-ultrix
5564 * New machines supported (target)
5566 AMD 29000 embedded, using EBMON a29k-none-none
5570 GDB continues to improve its handling of C++. `References' work better.
5571 The demangler has also been improved, and now deals with symbols mangled as
5572 per the Annotated C++ Reference Guide.
5574 GDB also now handles `stabs' symbol information embedded in MIPS
5575 `ecoff' symbol tables. Since the ecoff format was not easily
5576 extensible to handle new languages such as C++, this appeared to be a
5577 good way to put C++ debugging info into MIPS binaries. This option
5578 will be supported in the GNU C compiler, version 2, when it is
5581 * New features for SVR4
5583 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5584 shared libraries. Debugging dynamically linked programs should present
5585 only minor differences from debugging statically linked programs.
5587 The `info proc' command will print out information about any process
5588 on an SVR4 system (including the one you are debugging). At the moment,
5589 it prints the address mappings of the process.
5591 If you bring up GDB on another SVR4 system, please send mail to
5592 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5594 * Better dynamic linking support in SunOS
5596 Reading symbols from shared libraries which contain debugging symbols
5597 now works properly. However, there remain issues such as automatic
5598 skipping of `transfer vector' code during function calls, which
5599 make it harder to debug code in a shared library, than to debug the
5600 same code linked statically.
5604 GDB is now using the latest `getopt' routines from the FSF. This
5605 version accepts the -- prefix for options with long names. GDB will
5606 continue to accept the old forms (-option and +option) as well.
5607 Various single letter abbreviations for options have been explicity
5608 added to the option table so that they won't get overshadowed in the
5609 future by other options that begin with the same letter.
5613 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5614 Many assorted bugs have been handled. Many more remain to be handled.
5615 See the various ChangeLog files (primarily in gdb and bfd) for details.
5618 *** Changes in GDB-4.3:
5620 * New machines supported (host and target)
5622 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5623 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5624 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5626 * Almost SCO Unix support
5628 We had hoped to support:
5629 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5630 (except for core file support), but we discovered very late in the release
5631 that it has problems with process groups that render gdb unusable. Sorry
5632 about that. I encourage people to fix it and post the fixes.
5634 * Preliminary ELF and DWARF support
5636 GDB can read ELF object files on System V Release 4, and can handle
5637 debugging records for C, in DWARF format, in ELF files. This support
5638 is preliminary. If you bring up GDB on another SVR4 system, please
5639 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5644 GDB now uses the latest `readline' library. One user-visible change
5645 is that two tabs will list possible command completions, which previously
5646 required typing M-? (meta-question mark, or ESC ?).
5650 The `stepi' bug that many of you noticed has been squashed.
5651 Many bugs in C++ have been handled. Many more remain to be handled.
5652 See the various ChangeLog files (primarily in gdb and bfd) for details.
5654 * State of the MIPS world (in case you wondered):
5656 GDB can understand the symbol tables emitted by the compilers
5657 supplied by most vendors of MIPS-based machines, including DEC. These
5658 symbol tables are in a format that essentially nobody else uses.
5660 Some versions of gcc come with an assembler post-processor called
5661 mips-tfile. This program is required if you want to do source-level
5662 debugging of gcc-compiled programs. I believe FSF does not ship
5663 mips-tfile with gcc version 1, but it will eventually come with gcc
5666 Debugging of g++ output remains a problem. g++ version 1.xx does not
5667 really support it at all. (If you're lucky, you should be able to get
5668 line numbers and stack traces to work, but no parameters or local
5669 variables.) With some work it should be possible to improve the
5672 When gcc version 2 is released, you will have somewhat better luck.
5673 However, even then you will get confusing results for inheritance and
5676 We will eventually provide full debugging of g++ output on
5677 DECstations. This will probably involve some kind of stabs-in-ecoff
5678 encapulation, but the details have not been worked out yet.
5681 *** Changes in GDB-4.2:
5683 * Improved configuration
5685 Only one copy of `configure' exists now, and it is not self-modifying.
5686 Porting BFD is simpler.
5690 The `step' and `next' commands now only stop at the first instruction
5691 of a source line. This prevents the multiple stops that used to occur
5692 in switch statements, for-loops, etc. `Step' continues to stop if a
5693 function that has debugging information is called within the line.
5697 Lots of small bugs fixed. More remain.
5699 * New host supported (not target)
5701 Intel 386 PC clone running Mach i386-none-mach
5704 *** Changes in GDB-4.1:
5706 * Multiple source language support
5708 GDB now has internal scaffolding to handle several source languages.
5709 It determines the type of each source file from its filename extension,
5710 and will switch expression parsing and number formatting to match the
5711 language of the function in the currently selected stack frame.
5712 You can also specifically set the language to be used, with
5713 `set language c' or `set language modula-2'.
5717 GDB now has preliminary support for the GNU Modula-2 compiler,
5718 currently under development at the State University of New York at
5719 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5720 continue through the fall of 1991 and into 1992.
5722 Other Modula-2 compilers are currently not supported, and attempting to
5723 debug programs compiled with them will likely result in an error as the
5724 symbol table is read. Feel free to work on it, though!
5726 There are hooks in GDB for strict type checking and range checking,
5727 in the `Modula-2 philosophy', but they do not currently work.
5731 GDB can now write to executable and core files (e.g. patch
5732 a variable's value). You must turn this switch on, specify
5733 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5734 by assigning a new value to a variable. Modifications take
5737 * Automatic SunOS shared library reading
5739 When you run your program, GDB automatically determines where its
5740 shared libraries (if any) have been loaded, and reads their symbols.
5741 The `share' command is no longer needed. This also works when
5742 examining core files.
5746 You can specify the number of lines that the `list' command shows.
5749 * New machines supported (host and target)
5751 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5752 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5753 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5755 * New hosts supported (not targets)
5757 IBM RT/PC: romp-ibm-aix or rtpc
5759 * New targets supported (not hosts)
5761 AMD 29000 embedded with COFF a29k-none-coff
5762 AMD 29000 embedded with a.out a29k-none-aout
5763 Ultracomputer remote kernel debug a29k-nyu-kern
5765 * New remote interfaces
5771 *** Changes in GDB-4.0:
5775 Wide output is wrapped at good places to make the output more readable.
5777 Gdb now supports cross-debugging from a host machine of one type to a
5778 target machine of another type. Communication with the target system
5779 is over serial lines. The ``target'' command handles connecting to the
5780 remote system; the ``load'' command will download a program into the
5781 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5782 also supports debugging of realtime processes running under VxWorks,
5783 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5784 stub on the target system.
5786 New CPUs supported include the AMD 29000 and Intel 960.
5788 GDB now reads object files and symbol tables via a ``binary file''
5789 library, which allows a single copy of GDB to debug programs of multiple
5790 object file types such as a.out and coff.
5792 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5793 refcard.dvi and refcard.ps are available to format it).
5796 * Control-Variable user interface simplified
5798 All variables that control the operation of the debugger can be set
5799 by the ``set'' command, and displayed by the ``show'' command.
5801 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5802 ``Show prompt'' produces the response:
5803 Gdb's prompt is new-gdb=>.
5805 What follows are the NEW set commands. The command ``help set'' will
5806 print a complete list of old and new set commands. ``help set FOO''
5807 will give a longer description of the variable FOO. ``show'' will show
5808 all of the variable descriptions and their current settings.
5810 confirm on/off: Enables warning questions for operations that are
5811 hard to recover from, e.g. rerunning the program while
5812 it is already running. Default is ON.
5814 editing on/off: Enables EMACS style command line editing
5815 of input. Previous lines can be recalled with
5816 control-P, the current line can be edited with control-B,
5817 you can search for commands with control-R, etc.
5820 history filename NAME: NAME is where the gdb command history
5821 will be stored. The default is .gdb_history,
5822 or the value of the environment variable
5825 history size N: The size, in commands, of the command history. The
5826 default is 256, or the value of the environment variable
5829 history save on/off: If this value is set to ON, the history file will
5830 be saved after exiting gdb. If set to OFF, the
5831 file will not be saved. The default is OFF.
5833 history expansion on/off: If this value is set to ON, then csh-like
5834 history expansion will be performed on
5835 command line input. The default is OFF.
5837 radix N: Sets the default radix for input and output. It can be set
5838 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5839 in the current radix, so "set radix 10" is always a no-op.
5841 height N: This integer value is the number of lines on a page. Default
5842 is 24, the current `stty rows'' setting, or the ``li#''
5843 setting from the termcap entry matching the environment
5846 width N: This integer value is the number of characters on a line.
5847 Default is 80, the current `stty cols'' setting, or the ``co#''
5848 setting from the termcap entry matching the environment
5851 Note: ``set screensize'' is obsolete. Use ``set height'' and
5852 ``set width'' instead.
5854 print address on/off: Print memory addresses in various command displays,
5855 such as stack traces and structure values. Gdb looks
5856 more ``symbolic'' if you turn this off; it looks more
5857 ``machine level'' with it on. Default is ON.
5859 print array on/off: Prettyprint arrays. New convenient format! Default
5862 print demangle on/off: Print C++ symbols in "source" form if on,
5865 print asm-demangle on/off: Same, for assembler level printouts
5868 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5871 * Support for Epoch Environment.
5873 The epoch environment is a version of Emacs v18 with windowing. One
5874 new command, ``inspect'', is identical to ``print'', except that if you
5875 are running in the epoch environment, the value is printed in its own
5879 * Support for Shared Libraries
5881 GDB can now debug programs and core files that use SunOS shared libraries.
5882 Symbols from a shared library cannot be referenced
5883 before the shared library has been linked with the program (this
5884 happens after you type ``run'' and before the function main() is entered).
5885 At any time after this linking (including when examining core files
5886 from dynamically linked programs), gdb reads the symbols from each
5887 shared library when you type the ``sharedlibrary'' command.
5888 It can be abbreviated ``share''.
5890 sharedlibrary REGEXP: Load shared object library symbols for files
5891 matching a unix regular expression. No argument
5892 indicates to load symbols for all shared libraries.
5894 info sharedlibrary: Status of loaded shared libraries.
5899 A watchpoint stops execution of a program whenever the value of an
5900 expression changes. Checking for this slows down execution
5901 tremendously whenever you are in the scope of the expression, but is
5902 quite useful for catching tough ``bit-spreader'' or pointer misuse
5903 problems. Some machines such as the 386 have hardware for doing this
5904 more quickly, and future versions of gdb will use this hardware.
5906 watch EXP: Set a watchpoint (breakpoint) for an expression.
5908 info watchpoints: Information about your watchpoints.
5910 delete N: Deletes watchpoint number N (same as breakpoints).
5911 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5912 enable N: Re-enables watchpoint number N (same as breakpoints).
5915 * C++ multiple inheritance
5917 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5920 * C++ exception handling
5922 Gdb now supports limited C++ exception handling. Besides the existing
5923 ability to breakpoint on an exception handler, gdb can breakpoint on
5924 the raising of an exception (before the stack is peeled back to the
5927 catch FOO: If there is a FOO exception handler in the dynamic scope,
5928 set a breakpoint to catch exceptions which may be raised there.
5929 Multiple exceptions (``catch foo bar baz'') may be caught.
5931 info catch: Lists all exceptions which may be caught in the
5932 current stack frame.
5935 * Minor command changes
5937 The command ``call func (arg, arg, ...)'' now acts like the print
5938 command, except it does not print or save a value if the function's result
5939 is void. This is similar to dbx usage.
5941 The ``up'' and ``down'' commands now always print the frame they end up
5942 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5943 frames without printing.
5945 * New directory command
5947 'dir' now adds directories to the FRONT of the source search path.
5948 The path starts off empty. Source files that contain debug information
5949 about the directory in which they were compiled can be found even
5950 with an empty path; Sun CC and GCC include this information. If GDB can't
5951 find your source file in the current directory, type "dir .".
5953 * Configuring GDB for compilation
5955 For normal use, type ``./configure host''. See README or gdb.texinfo
5958 GDB now handles cross debugging. If you are remotely debugging between
5959 two different machines, type ``./configure host -target=targ''.
5960 Host is the machine where GDB will run; targ is the machine
5961 where the program that you are debugging will run.
projects / external / binutils.git / blob