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 * The command 'thread apply all' can now support new option '-ascending'
45 to call its specified command for all threads in ascending order.
47 * Python/Guile scripting
49 ** GDB now supports auto-loading of Python/Guile scripts contained in the
50 special section named `.debug_gdb_scripts'.
54 qXfer:btrace-conf:read
55 Return the branch trace configuration for the current thread.
57 *** Changes in GDB 7.9
59 * GDB now supports hardware watchpoints on x86 GNU Hurd.
63 ** You can now access frame registers from Python scripts.
64 ** New attribute 'producer' for gdb.Symtab objects.
65 ** gdb.Objfile objects have a new attribute "progspace",
66 which is the gdb.Progspace object of the containing program space.
67 ** gdb.Objfile objects have a new attribute "owner".
68 ** gdb.Objfile objects have a new attribute "build_id",
69 which is the build ID generated when the file was built.
70 ** gdb.Objfile objects have a new method "add_separate_debug_file".
71 ** A new event "gdb.clear_objfiles" has been added, triggered when
72 selecting a new file to debug.
73 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
74 ** New function gdb.lookup_objfile.
76 New events which are triggered when GDB modifies the state of the
79 ** gdb.events.inferior_call_pre: Function call is about to be made.
80 ** gdb.events.inferior_call_post: Function call has just been made.
81 ** gdb.events.memory_changed: A memory location has been altered.
82 ** gdb.events.register_changed: A register has been altered.
84 * New Python-based convenience functions:
86 ** $_caller_is(name [, number_of_frames])
87 ** $_caller_matches(regexp [, number_of_frames])
88 ** $_any_caller_is(name [, number_of_frames])
89 ** $_any_caller_matches(regexp [, number_of_frames])
91 * GDB now supports the compilation and injection of source code into
92 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
93 to compile the source code to object code, and if successful, inject
94 and execute that code within the current context of the inferior.
95 Currently the C language is supported. The commands used to
96 interface with this new feature are:
98 compile code [-raw|-r] [--] [source code]
99 compile file [-raw|-r] filename
103 demangle [-l language] [--] name
104 Demangle "name" in the specified language, or the current language
105 if elided. This command is renamed from the "maint demangle" command.
106 The latter is kept as a no-op to avoid "maint demangle" being interpreted
107 as "maint demangler-warning".
109 queue-signal signal-name-or-number
110 Queue a signal to be delivered to the thread when it is resumed.
112 add-auto-load-scripts-directory directory
113 Add entries to the list of directories from which to load auto-loaded
116 maint print user-registers
117 List all currently available "user" registers.
119 compile code [-r|-raw] [--] [source code]
120 Compile, inject, and execute in the inferior the executable object
121 code produced by compiling the provided source code.
123 compile file [-r|-raw] filename
124 Compile and inject into the inferior the executable object code
125 produced by compiling the source code stored in the filename
128 * On resume, GDB now always passes the signal the program had stopped
129 for to the thread the signal was sent to, even if the user changed
130 threads before resuming. Previously GDB would often (but not
131 always) deliver the signal to the thread that happens to be current
134 * Conversely, the "signal" command now consistently delivers the
135 requested signal to the current thread. GDB now asks for
136 confirmation if the program had stopped for a signal and the user
137 switched threads meanwhile.
139 * "breakpoint always-inserted" modes "off" and "auto" merged.
141 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
142 won't remove breakpoints from the target until all threads stop,
143 even in non-stop mode. The "auto" mode has been removed, and "off"
144 is now the default mode.
148 set debug symbol-lookup
149 show debug symbol-lookup
150 Control display of debugging info regarding symbol lookup.
154 ** The -list-thread-groups command outputs an exit-code field for
155 inferiors that have exited.
159 MIPS SDE mips*-sde*-elf*
163 Support for these obsolete configurations has been removed.
165 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
166 SGI Irix-5.x mips-*-irix5*
167 SGI Irix-6.x mips-*-irix6*
168 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
169 VAX running Ultrix vax-*-ultrix*
171 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
172 and "assf"), have been removed. Use the "sharedlibrary" command, or
173 its alias "share", instead.
175 *** Changes in GDB 7.8
177 * New command line options
180 This is an alias for the --data-directory option.
182 * GDB supports printing and modifying of variable length automatic arrays
183 as specified in ISO C99.
185 * The ARM simulator now supports instruction level tracing
186 with or without disassembly.
190 GDB now has support for scripting using Guile. Whether this is
191 available is determined at configure time.
192 Guile version 2.0 or greater is required.
193 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
195 * New commands (for set/show, see "New options" below)
199 Invoke CODE by passing it to the Guile interpreter.
203 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
205 info auto-load guile-scripts [regexp]
206 Print the list of automatically loaded Guile scripts.
208 * The source command is now capable of sourcing Guile scripts.
209 This feature is dependent on the debugger being built with Guile support.
213 set print symbol-loading (off|brief|full)
214 show print symbol-loading
215 Control whether to print informational messages when loading symbol
216 information for a file. The default is "full", but when debugging
217 programs with large numbers of shared libraries the amount of output
220 set guile print-stack (none|message|full)
221 show guile print-stack
222 Show a stack trace when an error is encountered in a Guile script.
224 set auto-load guile-scripts (on|off)
225 show auto-load guile-scripts
226 Control auto-loading of Guile script files.
228 maint ada set ignore-descriptive-types (on|off)
229 maint ada show ignore-descriptive-types
230 Control whether the debugger should ignore descriptive types in Ada
231 programs. The default is not to ignore the descriptive types. See
232 the user manual for more details on descriptive types and the intended
233 usage of this option.
235 set auto-connect-native-target
237 Control whether GDB is allowed to automatically connect to the
238 native target for the run, attach, etc. commands when not connected
239 to any target yet. See also "target native" below.
241 set record btrace replay-memory-access (read-only|read-write)
242 show record btrace replay-memory-access
243 Control what memory accesses are allowed during replay.
245 maint set target-async (on|off)
246 maint show target-async
247 This controls whether GDB targets operate in synchronous or
248 asynchronous mode. Normally the default is asynchronous, if it is
249 available; but this can be changed to more easily debug problems
250 occurring only in synchronous mode.
252 set mi-async (on|off)
254 Control whether MI asynchronous mode is preferred. This supersedes
255 "set target-async" of previous GDB versions.
257 * "set target-async" is deprecated as a CLI option and is now an alias
258 for "set mi-async" (only puts MI into async mode).
260 * Background execution commands (e.g., "c&", "s&", etc.) are now
261 possible ``out of the box'' if the target supports them. Previously
262 the user would need to explicitly enable the possibility with the
263 "set target-async on" command.
265 * New features in the GDB remote stub, GDBserver
267 ** New option --debug-format=option1[,option2,...] allows one to add
268 additional text to each output. At present only timestamps
269 are supported: --debug-format=timestamps.
270 Timestamps can also be turned on with the
271 "monitor set debug-format timestamps" command from GDB.
273 * The 'record instruction-history' command now starts counting instructions
274 at one. This also affects the instruction ranges reported by the
275 'record function-call-history' command when given the /i modifier.
277 * The command 'record function-call-history' supports a new modifier '/c' to
278 indent the function names based on their call stack depth.
279 The fields for the '/i' and '/l' modifier have been reordered.
280 The source line range is now prefixed with 'at'.
281 The instruction range is now prefixed with 'inst'.
282 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
283 "record instruction-history" and "list" commands.
285 * The ranges given as arguments to the 'record function-call-history' and
286 'record instruction-history' commands are now inclusive.
288 * The btrace record target now supports the 'record goto' command.
289 For locations inside the execution trace, the back trace is computed
290 based on the information stored in the execution trace.
292 * The btrace record target supports limited reverse execution and replay.
293 The target does not record data and therefore does not allow reading
296 * The "catch syscall" command now works on s390*-linux* targets.
298 * The "compare-sections" command is no longer specific to target
299 remote. It now works with all targets.
301 * All native targets are now consistently called "native".
302 Consequently, the "target child", "target GNU", "target djgpp",
303 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
304 commands have been replaced with "target native". The QNX/NTO port
305 leaves the "procfs" target in place and adds a "native" target for
306 consistency with other ports. The impact on users should be minimal
307 as these commands previously either throwed an error, or were
308 no-ops. The target's name is visible in the output of the following
309 commands: "help target", "info target", "info files", "maint print
312 * The "target native" command now connects to the native target. This
313 can be used to launch native programs even when "set
314 auto-connect-native-target" is set to off.
316 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
318 * Support for Intel(R) AVX-512 registers on GNU/Linux.
319 Support displaying and modifying Intel(R) AVX-512 registers
320 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
324 qXfer:btrace:read's annex
325 The qXfer:btrace:read packet supports a new annex 'delta' to read
326 branch trace incrementally.
330 ** Valid Python operations on gdb.Value objects representing
331 structs/classes invoke the corresponding overloaded operators if
333 ** New `Xmethods' feature in the Python API. Xmethods are
334 additional methods or replacements for existing methods of a C++
335 class. This feature is useful for those cases where a method
336 defined in C++ source code could be inlined or optimized out by
337 the compiler, making it unavailable to GDB.
340 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
342 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
343 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
344 its alias "share", instead.
346 * The commands "set remotebaud" and "show remotebaud" are no longer
347 supported. Use "set serial baud" and "show serial baud" (respectively)
352 ** A new option "-gdb-set mi-async" replaces "-gdb-set
353 target-async". The latter is left as a deprecated alias of the
354 former for backward compatibility. If the target supports it,
355 CLI background execution commands are now always possible by
356 default, independently of whether the frontend stated a
357 preference for asynchronous execution with "-gdb-set mi-async".
358 Previously "-gdb-set target-async off" affected both MI execution
359 commands and CLI execution commands.
361 *** Changes in GDB 7.7
363 * Improved support for process record-replay and reverse debugging on
364 arm*-linux* targets. Support for thumb32 and syscall instruction
365 recording has been added.
367 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
369 * GDB now supports Fission DWP file format version 2.
370 http://gcc.gnu.org/wiki/DebugFission
372 * New convenience function "$_isvoid", to check whether an expression
373 is void. A void expression is an expression where the type of the
374 result is "void". For example, some convenience variables may be
375 "void" when evaluated (e.g., "$_exitcode" before the execution of
376 the program being debugged; or an undefined convenience variable).
377 Another example, when calling a function whose return type is
380 * The "maintenance print objfiles" command now takes an optional regexp.
382 * The "catch syscall" command now works on arm*-linux* targets.
384 * GDB now consistently shows "<not saved>" when printing values of
385 registers the debug info indicates have not been saved in the frame
386 and there's nowhere to retrieve them from
387 (callee-saved/call-clobbered registers):
392 (gdb) info registers rax
395 Before, the former would print "<optimized out>", and the latter
396 "*value not available*".
398 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
403 ** Frame filters and frame decorators have been added.
404 ** Temporary breakpoints are now supported.
405 ** Line tables representation has been added.
406 ** New attribute 'parent_type' for gdb.Field objects.
407 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
408 ** New attribute 'name' for gdb.Type objects.
412 Nios II ELF nios2*-*-elf
413 Nios II GNU/Linux nios2*-*-linux
414 Texas Instruments MSP430 msp430*-*-elf
416 * Removed native configurations
418 Support for these a.out NetBSD and OpenBSD obsolete configurations has
419 been removed. ELF variants of these configurations are kept supported.
421 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
422 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
423 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
424 i[34567]86-*-openbsd3.[0-3]
425 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
426 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
427 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
431 Like "catch throw", but catches a re-thrown exception.
433 Renamed from old "maint check-symtabs".
435 Perform consistency checks on symtabs.
437 Expand symtabs matching an optional regexp.
440 Display the details of GDB configure-time options.
442 maint set|show per-command
443 maint set|show per-command space
444 maint set|show per-command time
445 maint set|show per-command symtab
446 Enable display of per-command gdb resource usage.
448 remove-symbol-file FILENAME
449 remove-symbol-file -a ADDRESS
450 Remove a symbol file added via add-symbol-file. The file to remove
451 can be identified by its filename or by an address that lies within
452 the boundaries of this symbol file in memory.
455 info exceptions REGEXP
456 Display the list of Ada exceptions defined in the program being
457 debugged. If provided, only the exceptions whose names match REGEXP
462 set debug symfile off|on
464 Control display of debugging info regarding reading symbol files and
465 symbol tables within those files
467 set print raw frame-arguments
468 show print raw frame-arguments
469 Set/show whether to print frame arguments in raw mode,
470 disregarding any defined pretty-printers.
472 set remote trace-status-packet
473 show remote trace-status-packet
474 Set/show the use of remote protocol qTStatus packet.
478 Control display of debugging messages related to Nios II targets.
482 Control whether target-assisted range stepping is enabled.
484 set startup-with-shell
485 show startup-with-shell
486 Specifies whether Unix child processes are started via a shell or
491 Use the target memory cache for accesses to the code segment. This
492 improves performance of remote debugging (particularly disassembly).
494 * You can now use a literal value 'unlimited' for options that
495 interpret 0 or -1 as meaning "unlimited". E.g., "set
496 trace-buffer-size unlimited" is now an alias for "set
497 trace-buffer-size -1" and "set height unlimited" is now an alias for
500 * The "set debug symtab-create" debugging option of GDB has been changed to
501 accept a verbosity level. 0 means "off", 1 provides basic debugging
502 output, and values of 2 or greater provides more verbose output.
504 * New command-line options
506 Display the details of GDB configure-time options.
508 * The command 'tsave' can now support new option '-ctf' to save trace
509 buffer in Common Trace Format.
511 * Newly installed $prefix/bin/gcore acts as a shell interface for the
514 * GDB now implements the the C++ 'typeid' operator.
516 * The new convenience variable $_exception holds the exception being
517 thrown or caught at an exception-related catchpoint.
519 * The exception-related catchpoints, like "catch throw", now accept a
520 regular expression which can be used to filter exceptions by type.
522 * The new convenience variable $_exitsignal is automatically set to
523 the terminating signal number when the program being debugged dies
524 due to an uncaught signal.
528 ** All MI commands now accept an optional "--language" option.
529 Support for this feature can be verified by using the "-list-features"
530 command, which should contain "language-option".
532 ** The new command -info-gdb-mi-command allows the user to determine
533 whether a GDB/MI command is supported or not.
535 ** The "^error" result record returned when trying to execute an undefined
536 GDB/MI command now provides a variable named "code" whose content is the
537 "undefined-command" error code. Support for this feature can be verified
538 by using the "-list-features" command, which should contain
539 "undefined-command-error-code".
541 ** The -trace-save MI command can optionally save trace buffer in Common
544 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
546 ** The command -data-list-register-values now accepts an optional
547 "--skip-unavailable" option. When used, only the available registers
550 ** The new command -trace-frame-collected dumps collected variables,
551 computed expressions, tvars, memory and registers in a traceframe.
553 ** The commands -stack-list-locals, -stack-list-arguments and
554 -stack-list-variables now accept an option "--skip-unavailable".
555 When used, only the available locals or arguments are displayed.
557 ** The -exec-run command now accepts an optional "--start" option.
558 When used, the command follows the same semantics as the "start"
559 command, stopping the program's execution at the start of its
560 main subprogram. Support for this feature can be verified using
561 the "-list-features" command, which should contain
562 "exec-run-start-option".
564 ** The new commands -catch-assert and -catch-exceptions insert
565 catchpoints stopping the program when Ada exceptions are raised.
567 ** The new command -info-ada-exceptions provides the equivalent of
568 the new "info exceptions" command.
570 * New system-wide configuration scripts
571 A GDB installation now provides scripts suitable for use as system-wide
572 configuration scripts for the following systems:
576 * GDB now supports target-assigned range stepping with remote targets.
577 This improves the performance of stepping source lines by reducing
578 the number of control packets from/to GDB. See "New remote packets"
581 * GDB now understands the element 'tvar' in the XML traceframe info.
582 It has the id of the collected trace state variables.
584 * On S/390 targets that provide the transactional-execution feature,
585 the program interruption transaction diagnostic block (TDB) is now
586 represented as a number of additional "registers" in GDB.
592 The vCont packet supports a new 'r' action, that tells the remote
593 stub to step through an address range itself, without GDB
594 involvemement at each single-step.
596 qXfer:libraries-svr4:read's annex
597 The previously unused annex of the qXfer:libraries-svr4:read packet
598 is now used to support passing an argument list. The remote stub
599 reports support for this argument list to GDB's qSupported query.
600 The defined arguments are "start" and "prev", used to reduce work
601 necessary for library list updating, resulting in significant
604 * New features in the GDB remote stub, GDBserver
606 ** GDBserver now supports target-assisted range stepping. Currently
607 enabled on x86/x86_64 GNU/Linux targets.
609 ** GDBserver now adds element 'tvar' in the XML in the reply to
610 'qXfer:traceframe-info:read'. It has the id of the collected
611 trace state variables.
613 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
616 * New 'z' formatter for printing and examining memory, this displays the
617 value as hexadecimal zero padded on the left to the size of the type.
619 * GDB can now use Windows x64 unwinding data.
621 * The "set remotebaud" command has been replaced by "set serial baud".
622 Similarly, "show remotebaud" has been replaced by "show serial baud".
623 The "set remotebaud" and "show remotebaud" commands are still available
624 to provide backward compatibility with older versions of GDB.
626 *** Changes in GDB 7.6
628 * Target record has been renamed to record-full.
629 Record/replay is now enabled with the "record full" command.
630 This also affects settings that are associated with full record/replay
631 that have been moved from "set/show record" to "set/show record full":
633 set|show record full insn-number-max
634 set|show record full stop-at-limit
635 set|show record full memory-query
637 * A new record target "record-btrace" has been added. The new target
638 uses hardware support to record the control-flow of a process. It
639 does not support replaying the execution, but it implements the
640 below new commands for investigating the recorded execution log.
641 This new recording method can be enabled using:
645 The "record-btrace" target is only available on Intel Atom processors
646 and requires a Linux kernel 2.6.32 or later.
648 * Two new commands have been added for record/replay to give information
649 about the recorded execution without having to replay the execution.
650 The commands are only supported by "record btrace".
652 record instruction-history prints the execution history at
653 instruction granularity
655 record function-call-history prints the execution history at
658 * New native configurations
660 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
661 FreeBSD/powerpc powerpc*-*-freebsd
662 x86_64/Cygwin x86_64-*-cygwin*
663 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
667 ARM AArch64 aarch64*-*-elf
668 ARM AArch64 GNU/Linux aarch64*-*-linux
669 Lynx 178 PowerPC powerpc-*-lynx*178
670 x86_64/Cygwin x86_64-*-cygwin*
671 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
673 * If the configured location of system.gdbinit file (as given by the
674 --with-system-gdbinit option at configure time) is in the
675 data-directory (as specified by --with-gdb-datadir at configure
676 time) or in one of its subdirectories, then GDB will look for the
677 system-wide init file in the directory specified by the
678 --data-directory command-line option.
680 * New command line options:
682 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
683 other initialization files, unlike -nx which disables all of them.
685 * Removed command line options
687 -epoch This was used by the gdb mode in Epoch, an ancient fork of
690 * The 'ptype' and 'whatis' commands now accept an argument to control
693 * 'info proc' now works on some core files.
697 ** Vectors can be created with gdb.Type.vector.
699 ** Python's atexit.register now works in GDB.
701 ** Types can be pretty-printed via a Python API.
703 ** Python 3 is now supported (in addition to Python 2.4 or later)
705 ** New class gdb.Architecture exposes GDB's internal representation
706 of architecture in the Python API.
708 ** New method Frame.architecture returns the gdb.Architecture object
709 corresponding to the frame's architecture.
711 * New Python-based convenience functions:
713 ** $_memeq(buf1, buf2, length)
714 ** $_streq(str1, str2)
716 ** $_regex(str, regex)
718 * The 'cd' command now defaults to using '~' (the home directory) if not
721 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
722 default for GCC since November 2000.
724 * The command 'forward-search' can now be abbreviated as 'fo'.
726 * The command 'info tracepoints' can now display 'installed on target'
727 or 'not installed on target' for each non-pending location of tracepoint.
729 * New configure options
731 --enable-libmcheck/--disable-libmcheck
732 By default, development versions are built with -lmcheck on hosts
733 that support it, in order to help track memory corruption issues.
734 Release versions, on the other hand, are built without -lmcheck
735 by default. The --enable-libmcheck/--disable-libmcheck configure
736 options allow the user to override that default.
737 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
738 This configure option allows the user to build GDB with
739 libbabeltrace using which GDB can read Common Trace Format data.
741 * New commands (for set/show, see "New options" below)
744 Catch signals. This is similar to "handle", but allows commands and
745 conditions to be attached.
748 List the BFDs known to GDB.
750 python-interactive [command]
752 Start a Python interactive prompt, or evaluate the optional command
753 and print the result of expressions.
756 "py" is a new alias for "python".
758 enable type-printer [name]...
759 disable type-printer [name]...
760 Enable or disable type printers.
764 ** For the Renesas Super-H architecture, the "regs" command has been removed
765 (has been deprecated in GDB 7.5), and "info all-registers" should be used
770 set print type methods (on|off)
771 show print type methods
772 Control whether method declarations are displayed by "ptype".
773 The default is to show them.
775 set print type typedefs (on|off)
776 show print type typedefs
777 Control whether typedef definitions are displayed by "ptype".
778 The default is to show them.
780 set filename-display basename|relative|absolute
781 show filename-display
782 Control the way in which filenames is displayed.
783 The default is "relative", which preserves previous behavior.
785 set trace-buffer-size
786 show trace-buffer-size
787 Request target to change the size of trace buffer.
789 set remote trace-buffer-size-packet auto|on|off
790 show remote trace-buffer-size-packet
791 Control the use of the remote protocol `QTBuffer:size' packet.
795 Control display of debugging messages related to ARM AArch64.
798 set debug coff-pe-read
799 show debug coff-pe-read
800 Control display of debugging messages related to reading of COFF/PE
805 Control display of debugging messages related to Mach-O symbols
808 set debug notification
809 show debug notification
810 Control display of debugging info for async remote notification.
814 ** Command parameter changes are now notified using new async record
815 "=cmd-param-changed".
816 ** Trace frame changes caused by command "tfind" are now notified using
817 new async record "=traceframe-changed".
818 ** The creation, deletion and modification of trace state variables
819 are now notified using new async records "=tsv-created",
820 "=tsv-deleted" and "=tsv-modified".
821 ** The start and stop of process record are now notified using new
822 async record "=record-started" and "=record-stopped".
823 ** Memory changes are now notified using new async record
825 ** The data-disassemble command response will include a "fullname" field
826 containing the absolute file name when source has been requested.
827 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
828 command, to allow pattern filling of memory areas.
829 ** New commands "-catch-load"/"-catch-unload" added for intercepting
830 library load/unload events.
831 ** The response to breakpoint commands and breakpoint async records
832 includes an "installed" field containing a boolean state about each
833 non-pending tracepoint location is whether installed on target or not.
834 ** Output of the "-trace-status" command includes a "trace-file" field
835 containing the name of the trace file being examined. This field is
836 optional, and only present when examining a trace file.
837 ** The "fullname" field is now always present along with the "file" field,
838 even if the file cannot be found by GDB.
840 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
841 You must have the LZMA library available when configuring GDB for this
842 feature to be enabled. For more information, see:
843 http://fedoraproject.org/wiki/Features/MiniDebugInfo
848 Set the size of trace buffer. The remote stub reports support for this
849 packet to gdb's qSupported query.
852 Enable Branch Trace Store (BTS)-based branch tracing for the current
853 thread. The remote stub reports support for this packet to gdb's
857 Disable branch tracing for the current thread. The remote stub reports
858 support for this packet to gdb's qSupported query.
861 Read the traced branches for the current thread. The remote stub
862 reports support for this packet to gdb's qSupported query.
864 *** Changes in GDB 7.5
866 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
867 for more x32 ABI info.
869 * GDB now supports access to MIPS DSP registers on Linux targets.
871 * GDB now supports debugging microMIPS binaries.
873 * The "info os" command on GNU/Linux can now display information on
874 several new classes of objects managed by the operating system:
875 "info os procgroups" lists process groups
876 "info os files" lists file descriptors
877 "info os sockets" lists internet-domain sockets
878 "info os shm" lists shared-memory regions
879 "info os semaphores" lists semaphores
880 "info os msg" lists message queues
881 "info os modules" lists loaded kernel modules
883 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
884 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
885 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
886 options and inspect the probe arguments using the new $_probe_arg family
887 of convenience variables. You can obtain more information about SystemTap
888 in <http://sourceware.org/systemtap/>.
890 * GDB now supports reversible debugging on ARM, it allows you to
891 debug basic ARM and THUMB instructions, and provides
892 record/replay support.
894 * The option "symbol-reloading" has been deleted as it is no longer used.
898 ** GDB commands implemented in Python can now be put in command class
901 ** The "maint set python print-stack on|off" is now deleted.
903 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
904 apply "flag enum"-style pretty-printing to any enum.
906 ** gdb.lookup_symbol can now work when there is no current frame.
908 ** gdb.Symbol now has a 'line' attribute, holding the line number in
909 the source at which the symbol was defined.
911 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
912 method 'value'. The former indicates whether the symbol needs a
913 frame in order to compute its value, and the latter computes the
916 ** A new method 'referenced_value' on gdb.Value objects which can
917 dereference pointer as well as C++ reference values.
919 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
920 which return the global and static blocks (as gdb.Block objects),
921 of the underlying symbol table, respectively.
923 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
924 object associated with a PC value.
926 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
927 of the address range occupied by code for the current source line.
929 * Go language support.
930 GDB now supports debugging programs written in the Go programming
933 * GDBserver now supports stdio connections.
934 E.g. (gdb) target remote | ssh myhost gdbserver - hello
936 * The binary "gdbtui" can no longer be built or installed.
937 Use "gdb -tui" instead.
939 * GDB will now print "flag" enums specially. A flag enum is one where
940 all the enumerator values have no bits in common when pairwise
941 "and"ed. When printing a value whose type is a flag enum, GDB will
942 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
943 (gdb) print (enum E) 3
946 * The filename part of a linespec will now match trailing components
947 of a source file name. For example, "break gcc/expr.c:1000" will
948 now set a breakpoint in build/gcc/expr.c, but not
951 * The "info proc" and "generate-core-file" commands will now also
952 work on remote targets connected to GDBserver on Linux.
954 * The command "info catch" has been removed. It has been disabled
957 * The "catch exception" and "catch assert" commands now accept
958 a condition at the end of the command, much like the "break"
959 command does. For instance:
961 (gdb) catch exception Constraint_Error if Barrier = True
963 Previously, it was possible to add a condition to such catchpoints,
964 but it had to be done as a second step, after the catchpoint had been
965 created, using the "condition" command.
967 * The "info static-tracepoint-marker" command will now also work on
968 native Linux targets with in-process agent.
970 * GDB can now set breakpoints on inlined functions.
972 * The .gdb_index section has been updated to include symbols for
973 inlined functions. GDB will ignore older .gdb_index sections by
974 default, which could cause symbol files to be loaded more slowly
975 until their .gdb_index sections can be recreated. The new command
976 "set use-deprecated-index-sections on" will cause GDB to use any older
977 .gdb_index sections it finds. This will restore performance, but the
978 ability to set breakpoints on inlined functions will be lost in symbol
979 files with older .gdb_index sections.
981 The .gdb_index section has also been updated to record more information
982 about each symbol. This speeds up the "info variables", "info functions"
983 and "info types" commands when used with programs having the .gdb_index
984 section, as well as speeding up debugging with shared libraries using
985 the .gdb_index section.
987 * Ada support for GDB/MI Variable Objects has been added.
989 * GDB can now support 'breakpoint always-inserted mode' in 'record'
994 ** New command -info-os is the MI equivalent of "info os".
996 ** Output logs ("set logging" and related) now include MI output.
1000 ** "set use-deprecated-index-sections on|off"
1001 "show use-deprecated-index-sections on|off"
1002 Controls the use of deprecated .gdb_index sections.
1004 ** "catch load" and "catch unload" can be used to stop when a shared
1005 library is loaded or unloaded, respectively.
1007 ** "enable count" can be used to auto-disable a breakpoint after
1010 ** "info vtbl" can be used to show the virtual method tables for
1011 C++ and Java objects.
1013 ** "explore" and its sub commands "explore value" and "explore type"
1014 can be used to recursively explore values and types of
1015 expressions. These commands are available only if GDB is
1016 configured with '--with-python'.
1018 ** "info auto-load" shows status of all kinds of auto-loaded files,
1019 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1020 sequences of commands files, "info auto-load python-scripts"
1021 shows status of auto-loading Python script files,
1022 "info auto-load local-gdbinit" shows status of loading init file
1023 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1024 status of inferior specific thread debugging shared library loading.
1026 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1027 and "show auto-load-scripts" commands have been deprecated, use their
1028 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1029 and "show auto-load python-scripts" counterparts instead.
1031 ** "dprintf location,format,args..." creates a dynamic printf, which
1032 is basically a breakpoint that does a printf and immediately
1033 resumes your program's execution, so it is like a printf that you
1034 can insert dynamically at runtime instead of at compiletime.
1036 ** "set print symbol"
1038 Controls whether GDB attempts to display the symbol, if any,
1039 corresponding to addresses it prints. This defaults to "on", but
1040 you can set it to "off" to restore GDB's previous behavior.
1042 * Deprecated commands
1044 ** For the Renesas Super-H architecture, the "regs" command has been
1045 deprecated, and "info all-registers" should be used instead.
1049 Renesas RL78 rl78-*-elf
1050 HP OpenVMS ia64 ia64-hp-openvms*
1052 * GDBserver supports evaluation of breakpoint conditions. When
1053 support is advertised by GDBserver, GDB may be told to send the
1054 breakpoint conditions in bytecode form to GDBserver. GDBserver
1055 will only report the breakpoint trigger to GDB when its condition
1060 set mips compression
1061 show mips compression
1062 Select the compressed ISA encoding used in functions that have no symbol
1063 information available. The encoding can be set to either of:
1066 and is updated automatically from ELF file flags if available.
1068 set breakpoint condition-evaluation
1069 show breakpoint condition-evaluation
1070 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1071 GDBserver ("target"). Default option "auto" chooses the most efficient
1073 This option can improve debugger efficiency depending on the speed of the
1077 Disable auto-loading globally.
1080 Show auto-loading setting of all kinds of auto-loaded files.
1082 set auto-load gdb-scripts on|off
1083 show auto-load gdb-scripts
1084 Control auto-loading of GDB canned sequences of commands files.
1086 set auto-load python-scripts on|off
1087 show auto-load python-scripts
1088 Control auto-loading of Python script files.
1090 set auto-load local-gdbinit on|off
1091 show auto-load local-gdbinit
1092 Control loading of init file (.gdbinit) from current directory.
1094 set auto-load libthread-db on|off
1095 show auto-load libthread-db
1096 Control auto-loading of inferior specific thread debugging shared library.
1098 set auto-load scripts-directory <dir1>[:<dir2>...]
1099 show auto-load scripts-directory
1100 Set a list of directories from which to load auto-loaded scripts.
1101 Automatically loaded Python scripts and GDB scripts are located in one
1102 of the directories listed by this option.
1103 The delimiter (':' above) may differ according to the host platform.
1105 set auto-load safe-path <dir1>[:<dir2>...]
1106 show auto-load safe-path
1107 Set a list of directories from which it is safe to auto-load files.
1108 The delimiter (':' above) may differ according to the host platform.
1110 set debug auto-load on|off
1111 show debug auto-load
1112 Control display of debugging info for auto-loading the files above.
1114 set dprintf-style gdb|call|agent
1116 Control the way in which a dynamic printf is performed; "gdb"
1117 requests a GDB printf command, while "call" causes dprintf to call a
1118 function in the inferior. "agent" requests that the target agent
1119 (such as GDBserver) do the printing.
1121 set dprintf-function <expr>
1122 show dprintf-function
1123 set dprintf-channel <expr>
1124 show dprintf-channel
1125 Set the function and optional first argument to the call when using
1126 the "call" style of dynamic printf.
1128 set disconnected-dprintf on|off
1129 show disconnected-dprintf
1130 Control whether agent-style dynamic printfs continue to be in effect
1131 after GDB disconnects.
1133 * New configure options
1135 --with-auto-load-dir
1136 Configure default value for the 'set auto-load scripts-directory'
1137 setting above. It defaults to '$debugdir:$datadir/auto-load',
1138 $debugdir representing global debugging info directories (available
1139 via 'show debug-file-directory') and $datadir representing GDB's data
1140 directory (available via 'show data-directory').
1142 --with-auto-load-safe-path
1143 Configure default value for the 'set auto-load safe-path' setting
1144 above. It defaults to the --with-auto-load-dir setting.
1146 --without-auto-load-safe-path
1147 Set 'set auto-load safe-path' to '/', effectively disabling this
1150 * New remote packets
1152 z0/z1 conditional breakpoints extension
1154 The z0/z1 breakpoint insertion packets have been extended to carry
1155 a list of conditional expressions over to the remote stub depending on the
1156 condition evaluation mode. The use of this extension can be controlled
1157 via the "set remote conditional-breakpoints-packet" command.
1161 Specify the signals which the remote stub may pass to the debugged
1162 program without GDB involvement.
1164 * New command line options
1166 --init-command=FILE, -ix Like --command, -x but execute it
1167 before loading inferior.
1168 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1169 execute it before loading inferior.
1171 *** Changes in GDB 7.4
1173 * GDB now handles ambiguous linespecs more consistently; the existing
1174 FILE:LINE support has been expanded to other types of linespecs. A
1175 breakpoint will now be set on all matching locations in all
1176 inferiors, and locations will be added or removed according to
1179 * GDB now allows you to skip uninteresting functions and files when
1180 stepping with the "skip function" and "skip file" commands.
1182 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1183 and "show remote hardware-watchpoint-length-limit". These allows to
1184 set or show the maximum length limit (in bytes) of a remote
1185 target hardware watchpoint.
1187 This allows e.g. to use "unlimited" hardware watchpoints with the
1188 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1189 watchpoints are slower than real hardware watchpoints but are
1190 significantly faster than gdb software watchpoints.
1194 ** The register_pretty_printer function in module gdb.printing now takes
1195 an optional `replace' argument. If True, the new printer replaces any
1198 ** The "maint set python print-stack on|off" command has been
1199 deprecated and will be deleted in GDB 7.5.
1200 A new command: "set python print-stack none|full|message" has
1201 replaced it. Additionally, the default for "print-stack" is
1202 now "message", which just prints the error message without
1205 ** A prompt substitution hook (prompt_hook) is now available to the
1208 ** A new Python module, gdb.prompt has been added to the GDB Python
1209 modules library. This module provides functionality for
1210 escape sequences in prompts (used by set/show
1211 extended-prompt). These escape sequences are replaced by their
1212 corresponding value.
1214 ** Python commands and convenience-functions located in
1215 'data-directory'/python/gdb/command and
1216 'data-directory'/python/gdb/function are now automatically loaded
1219 ** Blocks now provide four new attributes. global_block and
1220 static_block will return the global and static blocks
1221 respectively. is_static and is_global are boolean attributes
1222 that indicate if the block is one of those two types.
1224 ** Symbols now provide the "type" attribute, the type of the symbol.
1226 ** The "gdb.breakpoint" function has been deprecated in favor of
1229 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1230 of a function. This class is based on the "finish" command
1231 available in the CLI.
1233 ** Type objects for struct and union types now allow access to
1234 the fields using standard Python dictionary (mapping) methods.
1235 For example, "some_type['myfield']" now works, as does
1236 "some_type.items()".
1238 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1241 ** A new function, "deep_items" has been added to the gdb.types
1242 module in the GDB Python modules library. This function returns
1243 an iterator over the fields of a struct or union type. Unlike
1244 the standard Python "iteritems" method, it will recursively traverse
1245 any anonymous fields.
1249 ** "*stopped" events can report several new "reason"s, such as
1252 ** Breakpoint changes are now notified using new async records, like
1253 "=breakpoint-modified".
1255 ** New command -ada-task-info.
1257 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1258 $sdir specifies the default system locations of shared libraries.
1259 $pdir specifies the directory where the libpthread used by the application
1262 GDB no longer looks in $sdir and $pdir after it has searched the directories
1263 mentioned in libthread-db-search-path. If you want to search those
1264 directories, they must be specified in libthread-db-search-path.
1265 The default value of libthread-db-search-path on GNU/Linux and Solaris
1266 systems is now "$sdir:$pdir".
1268 $pdir is not supported by gdbserver, it is currently ignored.
1269 $sdir is supported by gdbserver.
1271 * New configure option --with-iconv-bin.
1272 When using the internationalization support like the one in the GNU C
1273 library, GDB will invoke the "iconv" program to get a list of supported
1274 character sets. If this program lives in a non-standard location, one can
1275 use this option to specify where to find it.
1277 * When natively debugging programs on PowerPC BookE processors running
1278 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1279 watchpoints, which specify a mask in addition to an address to watch.
1280 The mask specifies that some bits of an address (the bits which are
1281 reset in the mask) should be ignored when matching the address accessed
1282 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1283 section in the user manual for more details.
1285 * The new option --once causes GDBserver to stop listening for connections once
1286 the first connection is made. The listening port used by GDBserver will
1287 become available after that.
1289 * New commands "info macros" and "alias" have been added.
1291 * New function parameters suffix @entry specifies value of function parameter
1292 at the time the function got called. Entry values are available only since
1298 "!" is now an alias of the "shell" command.
1299 Note that no space is needed between "!" and SHELL COMMAND.
1303 watch EXPRESSION mask MASK_VALUE
1304 The watch command now supports the mask argument which allows creation
1305 of masked watchpoints, if the current architecture supports this feature.
1307 info auto-load-scripts [REGEXP]
1308 This command was formerly named "maintenance print section-scripts".
1309 It is now generally useful and is no longer a maintenance-only command.
1311 info macro [-all] [--] MACRO
1312 The info macro command has new options `-all' and `--'. The first for
1313 printing all definitions of a macro. The second for explicitly specifying
1314 the end of arguments and the beginning of the macro name in case the macro
1315 name starts with a hyphen.
1317 collect[/s] EXPRESSIONS
1318 The tracepoint collect command now takes an optional modifier "/s"
1319 that directs it to dereference pointer-to-character types and
1320 collect the bytes of memory up to a zero byte. The behavior is
1321 similar to what you see when you use the regular print command on a
1322 string. An optional integer following the "/s" sets a bound on the
1323 number of bytes that will be collected.
1326 The trace start command now interprets any supplied arguments as a
1327 note to be recorded with the trace run, with an effect similar to
1328 setting the variable trace-notes.
1331 The trace stop command now interprets any arguments as a note to be
1332 mentioned along with the tstatus report that the trace was stopped
1333 with a command. The effect is similar to setting the variable
1336 * Tracepoints can now be enabled and disabled at any time after a trace
1337 experiment has been started using the standard "enable" and "disable"
1338 commands. It is now possible to start a trace experiment with no enabled
1339 tracepoints; GDB will display a warning, but will allow the experiment to
1340 begin, assuming that tracepoints will be enabled as needed while the trace
1343 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1344 locations with 4-byte instructions, when they were previously
1345 limited to locations with instructions of 5 bytes or longer.
1349 set debug dwarf2-read
1350 show debug dwarf2-read
1351 Turns on or off display of debugging messages related to reading
1352 DWARF debug info. The default is off.
1354 set debug symtab-create
1355 show debug symtab-create
1356 Turns on or off display of debugging messages related to symbol table
1357 creation. The default is off.
1360 show extended-prompt
1361 Set the GDB prompt, and allow escape sequences to be inserted to
1362 display miscellaneous information (see 'help set extended-prompt'
1363 for the list of sequences). This prompt (and any information
1364 accessed through the escape sequences) is updated every time the
1365 prompt is displayed.
1367 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1368 show print entry-values
1369 Set printing of frame argument values at function entry. In some cases
1370 GDB can determine the value of function argument which was passed by the
1371 function caller, even if the value was modified inside the called function.
1373 set debug entry-values
1374 show debug entry-values
1375 Control display of debugging info for determining frame argument values at
1376 function entry and virtual tail call frames.
1378 set basenames-may-differ
1379 show basenames-may-differ
1380 Set whether a source file may have multiple base names.
1381 (A "base name" is the name of a file with the directory part removed.
1382 Example: The base name of "/home/user/hello.c" is "hello.c".)
1383 If set, GDB will canonicalize file names (e.g., expand symlinks)
1384 before comparing them. Canonicalization is an expensive operation,
1385 but it allows the same file be known by more than one base name.
1386 If not set (the default), all source files are assumed to have just
1387 one base name, and gdb will do file name comparisons more efficiently.
1393 Set a user name and notes for the current and any future trace runs.
1394 This is useful for long-running and/or disconnected traces, to
1395 inform others (or yourself) as to who is running the trace, supply
1396 contact information, or otherwise explain what is going on.
1398 set trace-stop-notes
1399 show trace-stop-notes
1400 Set a note attached to the trace run, that is displayed when the
1401 trace has been stopped by a tstop command. This is useful for
1402 instance as an explanation, if you are stopping a trace run that was
1403 started by someone else.
1405 * New remote packets
1409 Dynamically enable a tracepoint in a started trace experiment.
1413 Dynamically disable a tracepoint in a started trace experiment.
1417 Set the user and notes of the trace run.
1421 Query the current status of a tracepoint.
1425 Query the minimum length of instruction at which a fast tracepoint may
1428 * Dcache size (number of lines) and line-size are now runtime-configurable
1429 via "set dcache line" and "set dcache line-size" commands.
1433 Texas Instruments TMS320C6x tic6x-*-*
1437 Renesas RL78 rl78-*-elf
1439 *** Changes in GDB 7.3.1
1441 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1443 *** Changes in GDB 7.3
1445 * GDB has a new command: "thread find [REGEXP]".
1446 It finds the thread id whose name, target id, or thread extra info
1447 matches the given regular expression.
1449 * The "catch syscall" command now works on mips*-linux* targets.
1451 * The -data-disassemble MI command now supports modes 2 and 3 for
1452 dumping the instruction opcodes.
1454 * New command line options
1456 -data-directory DIR Specify DIR as the "data-directory".
1457 This is mostly for testing purposes.
1459 * The "maint set python auto-load on|off" command has been renamed to
1460 "set auto-load-scripts on|off".
1462 * GDB has a new command: "set directories".
1463 It is like the "dir" command except that it replaces the
1464 source path list instead of augmenting it.
1466 * GDB now understands thread names.
1468 On GNU/Linux, "info threads" will display the thread name as set by
1469 prctl or pthread_setname_np.
1471 There is also a new command, "thread name", which can be used to
1472 assign a name internally for GDB to display.
1475 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1476 has been integrated into GDB.
1480 ** The function gdb.Write now accepts an optional keyword 'stream'.
1481 This keyword, when provided, will direct the output to either
1482 stdout, stderr, or GDB's logging output.
1484 ** Parameters can now be be sub-classed in Python, and in particular
1485 you may implement the get_set_doc and get_show_doc functions.
1486 This improves how Parameter set/show documentation is processed
1487 and allows for more dynamic content.
1489 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1490 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1491 have an is_valid method.
1493 ** Breakpoints can now be sub-classed in Python, and in particular
1494 you may implement a 'stop' function that is executed each time
1495 the inferior reaches that breakpoint.
1497 ** New function gdb.lookup_global_symbol looks up a global symbol.
1499 ** GDB values in Python are now callable if the value represents a
1500 function. For example, if 'some_value' represents a function that
1501 takes two integer parameters and returns a value, you can call
1502 that function like so:
1504 result = some_value (10,20)
1506 ** Module gdb.types has been added.
1507 It contains a collection of utilities for working with gdb.Types objects:
1508 get_basic_type, has_field, make_enum_dict.
1510 ** Module gdb.printing has been added.
1511 It contains utilities for writing and registering pretty-printers.
1512 New classes: PrettyPrinter, SubPrettyPrinter,
1513 RegexpCollectionPrettyPrinter.
1514 New function: register_pretty_printer.
1516 ** New commands "info pretty-printers", "enable pretty-printer" and
1517 "disable pretty-printer" have been added.
1519 ** gdb.parameter("directories") is now available.
1521 ** New function gdb.newest_frame returns the newest frame in the
1524 ** The gdb.InferiorThread class has a new "name" attribute. This
1525 holds the thread's name.
1527 ** Python Support for Inferior events.
1528 Python scripts can add observers to be notified of events
1529 occurring in the process being debugged.
1530 The following events are currently supported:
1531 - gdb.events.cont Continue event.
1532 - gdb.events.exited Inferior exited event.
1533 - gdb.events.stop Signal received, and Breakpoint hit events.
1537 ** GDB now puts template parameters in scope when debugging in an
1538 instantiation. For example, if you have:
1540 template<int X> int func (void) { return X; }
1542 then if you step into func<5>, "print X" will show "5". This
1543 feature requires proper debuginfo support from the compiler; it
1544 was added to GCC 4.5.
1546 ** The motion commands "next", "finish", "until", and "advance" now
1547 work better when exceptions are thrown. In particular, GDB will
1548 no longer lose control of the inferior; instead, the GDB will
1549 stop the inferior at the point at which the exception is caught.
1550 This functionality requires a change in the exception handling
1551 code that was introduced in GCC 4.5.
1553 * GDB now follows GCC's rules on accessing volatile objects when
1554 reading or writing target state during expression evaluation.
1555 One notable difference to prior behavior is that "print x = 0"
1556 no longer generates a read of x; the value of the assignment is
1557 now always taken directly from the value being assigned.
1559 * GDB now has some support for using labels in the program's source in
1560 linespecs. For instance, you can use "advance label" to continue
1561 execution to a label.
1563 * GDB now has support for reading and writing a new .gdb_index
1564 section. This section holds a fast index of DWARF debugging
1565 information and can be used to greatly speed up GDB startup and
1566 operation. See the documentation for `save gdb-index' for details.
1568 * The "watch" command now accepts an optional "-location" argument.
1569 When used, this causes GDB to watch the memory referred to by the
1570 expression. Such a watchpoint is never deleted due to it going out
1573 * GDB now supports thread debugging of core dumps on GNU/Linux.
1575 GDB now activates thread debugging using the libthread_db library
1576 when debugging GNU/Linux core dumps, similarly to when debugging
1577 live processes. As a result, when debugging a core dump file, GDB
1578 is now able to display pthread_t ids of threads. For example, "info
1579 threads" shows the same output as when debugging the process when it
1580 was live. In earlier releases, you'd see something like this:
1583 * 1 LWP 6780 main () at main.c:10
1585 While now you see this:
1588 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1590 It is also now possible to inspect TLS variables when debugging core
1593 When debugging a core dump generated on a machine other than the one
1594 used to run GDB, you may need to point GDB at the correct
1595 libthread_db library with the "set libthread-db-search-path"
1596 command. See the user manual for more details on this command.
1598 * When natively debugging programs on PowerPC BookE processors running
1599 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1600 which stop execution of the inferior whenever it executes an instruction
1601 at any address within the specified range. See the "PowerPC Embedded"
1602 section in the user manual for more details.
1604 * New features in the GDB remote stub, GDBserver
1606 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1607 and i686 LynxOS (version 5.x).
1609 ** GDBserver is now supported on Blackfin Linux.
1611 * New native configurations
1613 ia64 HP-UX ia64-*-hpux*
1617 Analog Devices, Inc. Blackfin Processor bfin-*
1619 * Ada task switching is now supported on sparc-elf targets when
1620 debugging a program using the Ravenscar Profile. For more information,
1621 see the "Tasking Support when using the Ravenscar Profile" section
1622 in the GDB user manual.
1624 * Guile support was removed.
1626 * New features in the GNU simulator
1628 ** The --map-info flag lists all known core mappings.
1630 ** CFI flashes may be simulated via the "cfi" device.
1632 *** Changes in GDB 7.2
1634 * Shared library support for remote targets by default
1636 When GDB is configured for a generic, non-OS specific target, like
1637 for example, --target=arm-eabi or one of the many *-*-elf targets,
1638 GDB now queries remote stubs for loaded shared libraries using the
1639 `qXfer:libraries:read' packet. Previously, shared library support
1640 was always disabled for such configurations.
1644 ** Argument Dependent Lookup (ADL)
1646 In C++ ADL lookup directs function search to the namespaces of its
1647 arguments even if the namespace has not been imported.
1657 Here the compiler will search for `foo' in the namespace of 'b'
1658 and find A::foo. GDB now supports this. This construct is commonly
1659 used in the Standard Template Library for operators.
1661 ** Improved User Defined Operator Support
1663 In addition to member operators, GDB now supports lookup of operators
1664 defined in a namespace and imported with a `using' directive, operators
1665 defined in the global scope, operators imported implicitly from an
1666 anonymous namespace, and the ADL operators mentioned in the previous
1668 GDB now also supports proper overload resolution for all the previously
1669 mentioned flavors of operators.
1671 ** static const class members
1673 Printing of static const class members that are initialized in the
1674 class definition has been fixed.
1676 * Windows Thread Information Block access.
1678 On Windows targets, GDB now supports displaying the Windows Thread
1679 Information Block (TIB) structure. This structure is visible either
1680 by using the new command `info w32 thread-information-block' or, by
1681 dereferencing the new convenience variable named `$_tlb', a
1682 thread-specific pointer to the TIB. This feature is also supported
1683 when remote debugging using GDBserver.
1685 * Static tracepoints
1687 Static tracepoints are calls in the user program into a tracing
1688 library. One such library is a port of the LTTng kernel tracer to
1689 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1690 When debugging with GDBserver, GDB now supports combining the GDB
1691 tracepoint machinery with such libraries. For example: the user can
1692 use GDB to probe a static tracepoint marker (a call from the user
1693 program into the tracing library) with the new "strace" command (see
1694 "New commands" below). This creates a "static tracepoint" in the
1695 breakpoint list, that can be manipulated with the same feature set
1696 as fast and regular tracepoints. E.g., collect registers, local and
1697 global variables, collect trace state variables, and define
1698 tracepoint conditions. In addition, the user can collect extra
1699 static tracepoint marker specific data, by collecting the new
1700 $_sdata internal variable. When analyzing the trace buffer, you can
1701 inspect $_sdata like any other variable available to GDB. For more
1702 information, see the "Tracepoints" chapter in GDB user manual. New
1703 remote packets have been defined to support static tracepoints, see
1704 the "New remote packets" section below.
1706 * Better reconstruction of tracepoints after disconnected tracing
1708 GDB will attempt to download the original source form of tracepoint
1709 definitions when starting a trace run, and then will upload these
1710 upon reconnection to the target, resulting in a more accurate
1711 reconstruction of the tracepoints that are in use on the target.
1715 You can now exercise direct control over the ways that GDB can
1716 affect your program. For instance, you can disallow the setting of
1717 breakpoints, so that the program can run continuously (assuming
1718 non-stop mode). In addition, the "observer" variable is available
1719 to switch all of the different controls; in observer mode, GDB
1720 cannot affect the target's behavior at all, which is useful for
1721 tasks like diagnosing live systems in the field.
1723 * The new convenience variable $_thread holds the number of the
1726 * New remote packets
1730 Return the address of the Windows Thread Information Block of a given thread.
1734 In response to several of the tracepoint packets, the target may now
1735 also respond with a number of intermediate `qRelocInsn' request
1736 packets before the final result packet, to have GDB handle
1737 relocating an instruction to execute at a different address. This
1738 is particularly useful for stubs that support fast tracepoints. GDB
1739 reports support for this feature in the qSupported packet.
1743 List static tracepoint markers in the target program.
1747 List static tracepoint markers at a given address in the target
1750 qXfer:statictrace:read
1752 Read the static trace data collected (by a `collect $_sdata'
1753 tracepoint action). The remote stub reports support for this packet
1754 to gdb's qSupported query.
1758 Send the current settings of GDB's permission flags.
1762 Send part of the source (textual) form of a tracepoint definition,
1763 which includes location, conditional, and action list.
1765 * The source command now accepts a -s option to force searching for the
1766 script in the source search path even if the script name specifies
1769 * New features in the GDB remote stub, GDBserver
1771 - GDBserver now support tracepoints (including fast tracepoints, and
1772 static tracepoints). The feature is currently supported by the
1773 i386-linux and amd64-linux builds. See the "Tracepoints support
1774 in gdbserver" section in the manual for more information.
1776 GDBserver JIT compiles the tracepoint's conditional agent
1777 expression bytecode into native code whenever possible for low
1778 overhead dynamic tracepoints conditionals. For such tracepoints,
1779 an expression that examines program state is evaluated when the
1780 tracepoint is reached, in order to determine whether to capture
1781 trace data. If the condition is simple and false, processing the
1782 tracepoint finishes very quickly and no data is gathered.
1784 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1785 for static tracepoints support.
1787 - GDBserver now supports x86_64 Windows 64-bit debugging.
1789 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1790 it understands register description.
1792 * The --batch flag now disables pagination and queries.
1794 * X86 general purpose registers
1796 GDB now supports reading/writing byte, word and double-word x86
1797 general purpose registers directly. This means you can use, say,
1798 $ah or $ax to refer, respectively, to the byte register AH and
1799 16-bit word register AX that are actually portions of the 32-bit
1800 register EAX or 64-bit register RAX.
1802 * The `commands' command now accepts a range of breakpoints to modify.
1803 A plain `commands' following a command that creates multiple
1804 breakpoints affects all the breakpoints set by that command. This
1805 applies to breakpoints set by `rbreak', and also applies when a
1806 single `break' command creates multiple breakpoints (e.g.,
1807 breakpoints on overloaded c++ functions).
1809 * The `rbreak' command now accepts a filename specification as part of
1810 its argument, limiting the functions selected by the regex to those
1811 in the specified file.
1813 * Support for remote debugging Windows and SymbianOS shared libraries
1814 from Unix hosts has been improved. Non Windows GDB builds now can
1815 understand target reported file names that follow MS-DOS based file
1816 system semantics, such as file names that include drive letters and
1817 use the backslash character as directory separator. This makes it
1818 possible to transparently use the "set sysroot" and "set
1819 solib-search-path" on Unix hosts to point as host copies of the
1820 target's shared libraries. See the new command "set
1821 target-file-system-kind" described below, and the "Commands to
1822 specify files" section in the user manual for more information.
1826 eval template, expressions...
1827 Convert the values of one or more expressions under the control
1828 of the string template to a command line, and call it.
1830 set target-file-system-kind unix|dos-based|auto
1831 show target-file-system-kind
1832 Set or show the assumed file system kind for target reported file
1835 save breakpoints <filename>
1836 Save all current breakpoint definitions to a file suitable for use
1837 in a later debugging session. To read the saved breakpoint
1838 definitions, use the `source' command.
1840 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1843 info static-tracepoint-markers
1844 Display information about static tracepoint markers in the target.
1846 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1847 Define a static tracepoint by probing a marker at the given
1848 function, line, address, or marker ID.
1852 Enable and disable observer mode.
1854 set may-write-registers on|off
1855 set may-write-memory on|off
1856 set may-insert-breakpoints on|off
1857 set may-insert-tracepoints on|off
1858 set may-insert-fast-tracepoints on|off
1859 set may-interrupt on|off
1860 Set individual permissions for GDB effects on the target. Note that
1861 some of these settings can have undesirable or surprising
1862 consequences, particularly when changed in the middle of a session.
1863 For instance, disabling the writing of memory can prevent
1864 breakpoints from being inserted, cause single-stepping to fail, or
1865 even crash your program, if you disable after breakpoints have been
1866 inserted. However, GDB should not crash.
1868 set record memory-query on|off
1869 show record memory-query
1870 Control whether to stop the inferior if memory changes caused
1871 by an instruction cannot be recorded.
1876 The disassemble command now supports "start,+length" form of two arguments.
1880 ** GDB now provides a new directory location, called the python directory,
1881 where Python scripts written for GDB can be installed. The location
1882 of that directory is <data-directory>/python, where <data-directory>
1883 is the GDB data directory. For more details, see section `Scripting
1884 GDB using Python' in the manual.
1886 ** The GDB Python API now has access to breakpoints, symbols, symbol
1887 tables, program spaces, inferiors, threads and frame's code blocks.
1888 Additionally, GDB Parameters can now be created from the API, and
1889 manipulated via set/show in the CLI.
1891 ** New functions gdb.target_charset, gdb.target_wide_charset,
1892 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1894 ** New exception gdb.GdbError.
1896 ** Pretty-printers are now also looked up in the current program space.
1898 ** Pretty-printers can now be individually enabled and disabled.
1900 ** GDB now looks for names of Python scripts to auto-load in a
1901 special section named `.debug_gdb_scripts', in addition to looking
1902 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1904 * Tracepoint actions were unified with breakpoint commands. In particular,
1905 there are no longer differences in "info break" output for breakpoints and
1906 tracepoints and the "commands" command can be used for both tracepoints and
1907 regular breakpoints.
1911 ARM Symbian arm*-*-symbianelf*
1913 * D language support.
1914 GDB now supports debugging programs written in the D programming
1917 * GDB now supports the extended ptrace interface for PowerPC which is
1918 available since Linux kernel version 2.6.34. This automatically enables
1919 any hardware breakpoints and additional hardware watchpoints available in
1920 the processor. The old ptrace interface exposes just one hardware
1921 watchpoint and no hardware breakpoints.
1923 * GDB is now able to use the Data Value Compare (DVC) register available on
1924 embedded PowerPC processors to implement in hardware simple watchpoint
1925 conditions of the form:
1927 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1929 This works in native GDB running on Linux kernels with the extended ptrace
1930 interface mentioned above.
1932 *** Changes in GDB 7.1
1936 ** Namespace Support
1938 GDB now supports importing of namespaces in C++. This enables the
1939 user to inspect variables from imported namespaces. Support for
1940 namepace aliasing has also been added. So, if a namespace is
1941 aliased in the current scope (e.g. namepace C=A; ) the user can
1942 print variables using the alias (e.g. (gdb) print C::x).
1946 All known bugs relating to the printing of virtual base class were
1947 fixed. It is now possible to call overloaded static methods using a
1952 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1953 and reinterpret_cast<> are now handled by the C++ expression parser.
1957 Xilinx MicroBlaze microblaze-*-*
1962 Xilinx MicroBlaze microblaze
1965 * Multi-program debugging.
1967 GDB now has support for multi-program (a.k.a. multi-executable or
1968 multi-exec) debugging. This allows for debugging multiple inferiors
1969 simultaneously each running a different program under the same GDB
1970 session. See "Debugging Multiple Inferiors and Programs" in the
1971 manual for more information. This implied some user visible changes
1972 in the multi-inferior support. For example, "info inferiors" now
1973 lists inferiors that are not running yet or that have exited
1974 already. See also "New commands" and "New options" below.
1976 * New tracing features
1978 GDB's tracepoint facility now includes several new features:
1980 ** Trace state variables
1982 GDB tracepoints now include support for trace state variables, which
1983 are variables managed by the target agent during a tracing
1984 experiment. They are useful for tracepoints that trigger each
1985 other, so for instance one tracepoint can count hits in a variable,
1986 and then a second tracepoint has a condition that is true when the
1987 count reaches a particular value. Trace state variables share the
1988 $-syntax of GDB convenience variables, and can appear in both
1989 tracepoint actions and condition expressions. Use the "tvariable"
1990 command to create, and "info tvariables" to view; see "Trace State
1991 Variables" in the manual for more detail.
1995 GDB now includes an option for defining fast tracepoints, which
1996 targets may implement more efficiently, such as by installing a jump
1997 into the target agent rather than a trap instruction. The resulting
1998 speedup can be by two orders of magnitude or more, although the
1999 tradeoff is that some program locations on some target architectures
2000 might not allow fast tracepoint installation, for instance if the
2001 instruction to be replaced is shorter than the jump. To request a
2002 fast tracepoint, use the "ftrace" command, with syntax identical to
2003 the regular trace command.
2005 ** Disconnected tracing
2007 It is now possible to detach GDB from the target while it is running
2008 a trace experiment, then reconnect later to see how the experiment
2009 is going. In addition, a new variable disconnected-tracing lets you
2010 tell the target agent whether to continue running a trace if the
2011 connection is lost unexpectedly.
2015 GDB now has the ability to save the trace buffer into a file, and
2016 then use that file as a target, similarly to you can do with
2017 corefiles. You can select trace frames, print data that was
2018 collected in them, and use tstatus to display the state of the
2019 tracing run at the moment that it was saved. To create a trace
2020 file, use "tsave <filename>", and to use it, do "target tfile
2023 ** Circular trace buffer
2025 You can ask the target agent to handle the trace buffer as a
2026 circular buffer, discarding the oldest trace frames to make room for
2027 newer ones, by setting circular-trace-buffer to on. This feature may
2028 not be available for all target agents.
2033 The disassemble command, when invoked with two arguments, now requires
2034 the arguments to be comma-separated.
2037 The info variables command now displays variable definitions. Files
2038 which only declare a variable are not shown.
2041 The source command is now capable of sourcing Python scripts.
2042 This feature is dependent on the debugger being build with Python
2045 Related to this enhancement is also the introduction of a new command
2046 "set script-extension" (see below).
2048 * New commands (for set/show, see "New options" below)
2050 record save [<FILENAME>]
2051 Save a file (in core file format) containing the process record
2052 execution log for replay debugging at a later time.
2054 record restore <FILENAME>
2055 Restore the process record execution log that was saved at an
2056 earlier time, for replay debugging.
2058 add-inferior [-copies <N>] [-exec <FILENAME>]
2061 clone-inferior [-copies <N>] [ID]
2062 Make a new inferior ready to execute the same program another
2063 inferior has loaded.
2068 maint info program-spaces
2069 List the program spaces loaded into GDB.
2071 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2072 show remote interrupt-sequence
2073 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2074 as the sequence to the remote target in order to interrupt the execution.
2075 Ctrl-C is a default. Some system prefers BREAK which is high level of
2076 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2077 Magic SysRq g. It is BREAK signal and character 'g'.
2079 set remote interrupt-on-connect [on | off]
2080 show remote interrupt-on-connect
2081 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2082 remote target when gdb connects to it. This is needed when you debug
2085 set remotebreak [on | off]
2087 Deprecated. Use "set/show remote interrupt-sequence" instead.
2089 tvariable $NAME [ = EXP ]
2090 Create or modify a trace state variable.
2093 List trace state variables and their values.
2095 delete tvariable $NAME ...
2096 Delete one or more trace state variables.
2099 Evaluate the given expressions without collecting anything into the
2100 trace buffer. (Valid in tracepoint actions only.)
2102 ftrace FN / FILE:LINE / *ADDR
2103 Define a fast tracepoint at the given function, line, or address.
2105 * New expression syntax
2107 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2108 GDB now parses 0b101010 identically with 42.
2112 set follow-exec-mode new|same
2113 show follow-exec-mode
2114 Control whether GDB reuses the same inferior across an exec call or
2115 creates a new one. This is useful to be able to restart the old
2116 executable after the inferior having done an exec call.
2118 set default-collect EXPR, ...
2119 show default-collect
2120 Define a list of expressions to be collected at each tracepoint.
2121 This is a useful way to ensure essential items are not overlooked,
2122 such as registers or a critical global variable.
2124 set disconnected-tracing
2125 show disconnected-tracing
2126 If set to 1, the target is instructed to continue tracing if it
2127 loses its connection to GDB. If 0, the target is to stop tracing
2130 set circular-trace-buffer
2131 show circular-trace-buffer
2132 If set to on, the target is instructed to use a circular trace buffer
2133 and discard the oldest trace frames instead of stopping the trace due
2134 to a full trace buffer. If set to off, the trace stops when the buffer
2135 fills up. Some targets may not support this.
2137 set script-extension off|soft|strict
2138 show script-extension
2139 If set to "off", the debugger does not perform any script language
2140 recognition, and all sourced files are assumed to be GDB scripts.
2141 If set to "soft" (the default), files are sourced according to
2142 filename extension, falling back to GDB scripts if the first
2144 If set to "strict", files are sourced according to filename extension.
2146 set ada trust-PAD-over-XVS on|off
2147 show ada trust-PAD-over-XVS
2148 If off, activate a workaround against a bug in the debugging information
2149 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2150 the GCC sources for more information about the GNAT encoding and
2151 PAD types in particular). It is always safe to set this option to
2152 off, but this introduces a slight performance penalty. The default
2155 * Python API Improvements
2157 ** GDB provides the new class gdb.LazyString. This is useful in
2158 some pretty-printing cases. The new method gdb.Value.lazy_string
2159 provides a simple way to create objects of this type.
2161 ** The fields returned by gdb.Type.fields now have an
2162 `is_base_class' attribute.
2164 ** The new method gdb.Type.range returns the range of an array type.
2166 ** The new method gdb.parse_and_eval can be used to parse and
2167 evaluate an expression.
2169 * New remote packets
2172 Define a trace state variable.
2175 Get the current value of a trace state variable.
2178 Set desired tracing behavior upon disconnection.
2181 Set the trace buffer to be linear or circular.
2184 Get data about the tracepoints currently in use.
2188 Process record now works correctly with hardware watchpoints.
2190 Multiple bug fixes have been made to the mips-irix port, making it
2191 much more reliable. In particular:
2192 - Debugging threaded applications is now possible again. Previously,
2193 GDB would hang while starting the program, or while waiting for
2194 the program to stop at a breakpoint.
2195 - Attaching to a running process no longer hangs.
2196 - An error occurring while loading a core file has been fixed.
2197 - Changing the value of the PC register now works again. This fixes
2198 problems observed when using the "jump" command, or when calling
2199 a function from GDB, or even when assigning a new value to $pc.
2200 - With the "finish" and "return" commands, the return value for functions
2201 returning a small array is now correctly printed.
2202 - It is now possible to break on shared library code which gets executed
2203 during a shared library init phase (code executed while executing
2204 their .init section). Previously, the breakpoint would have no effect.
2205 - GDB is now able to backtrace through the signal handler for
2206 non-threaded programs.
2208 PIE (Position Independent Executable) programs debugging is now supported.
2209 This includes debugging execution of PIC (Position Independent Code) shared
2210 libraries although for that, it should be possible to run such libraries as an
2213 *** Changes in GDB 7.0
2215 * GDB now has an interface for JIT compilation. Applications that
2216 dynamically generate code can create symbol files in memory and register
2217 them with GDB. For users, the feature should work transparently, and
2218 for JIT developers, the interface is documented in the GDB manual in the
2219 "JIT Compilation Interface" chapter.
2221 * Tracepoints may now be conditional. The syntax is as for
2222 breakpoints; either an "if" clause appended to the "trace" command,
2223 or the "condition" command is available. GDB sends the condition to
2224 the target for evaluation using the same bytecode format as is used
2225 for tracepoint actions.
2227 * The disassemble command now supports: an optional /r modifier, print the
2228 raw instructions in hex as well as in symbolic form, and an optional /m
2229 modifier to print mixed source+assembly.
2231 * Process record and replay
2233 In a architecture environment that supports ``process record and
2234 replay'', ``process record and replay'' target can record a log of
2235 the process execution, and replay it with both forward and reverse
2238 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2239 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2240 set execution-direction {forward|reverse}, for targets that support
2243 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2244 feature is available with a native GDB running on kernel version
2247 * GDB now has support for multi-byte and wide character sets on the
2248 target. Strings whose character type is wchar_t, char16_t, or
2249 char32_t are now correctly printed. GDB supports wide- and unicode-
2250 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2251 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2252 `printf'. This feature requires iconv to work properly; if your
2253 system does not have a working iconv, GDB can use GNU libiconv. See
2254 the installation instructions for more information.
2256 * GDB now supports automatic retrieval of shared library files from
2257 remote targets. To use this feature, specify a system root that begins
2258 with the `remote:' prefix, either via the `set sysroot' command or via
2259 the `--with-sysroot' configure-time option.
2261 * "info sharedlibrary" now takes an optional regex of libraries to show,
2262 and it now reports if a shared library has no debugging information.
2264 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2265 now complete on file names.
2267 * When completing in expressions, gdb will attempt to limit
2268 completions to allowable structure or union fields, where appropriate.
2269 For instance, consider:
2271 # struct example { int f1; double f2; };
2272 # struct example variable;
2275 If the user types TAB at the end of this command line, the available
2276 completions will be "f1" and "f2".
2278 * Inlined functions are now supported. They show up in backtraces, and
2279 the "step", "next", and "finish" commands handle them automatically.
2281 * GDB now supports the token-splicing (##) and stringification (#)
2282 operators when expanding macros. It also supports variable-arity
2285 * GDB now supports inspecting extra signal information, exported by
2286 the new $_siginfo convenience variable. The feature is currently
2287 implemented on linux ARM, i386 and amd64.
2289 * GDB can now display the VFP floating point registers and NEON vector
2290 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2291 can provide these registers (requires Linux 2.6.30 or later). Remote
2292 and simulator targets may also provide them.
2294 * New remote packets
2297 Search memory for a sequence of bytes.
2300 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2301 operation over reliable transport links. Use of this packet is
2302 controlled by the `set remote noack-packet' command.
2305 Kill the process with the specified process ID. Use this in preference
2306 to `k' when multiprocess protocol extensions are supported.
2309 Obtains additional operating system information
2313 Read or write additional signal information.
2315 * Removed remote protocol undocumented extension
2317 An undocumented extension to the remote protocol's `S' stop reply
2318 packet that permited the stub to pass a process id was removed.
2319 Remote servers should use the `T' stop reply packet instead.
2321 * GDB now supports multiple function calling conventions according to the
2322 DWARF-2 DW_AT_calling_convention function attribute.
2324 * The SH target utilizes the aforementioned change to distinguish between gcc
2325 and Renesas calling convention. It also adds the new CLI commands
2326 `set/show sh calling-convention'.
2328 * GDB can now read compressed debug sections, as produced by GNU gold
2329 with the --compress-debug-sections=zlib flag.
2331 * 64-bit core files are now supported on AIX.
2333 * Thread switching is now supported on Tru64.
2335 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2336 which will be allocated using malloc later in program execution.
2338 * The qXfer:libraries:read remote procotol packet now allows passing a
2339 list of section offsets.
2341 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2342 conditions handling signals delivered during attach or thread creation
2343 have also been fixed.
2345 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2346 From the user's standpoint, all unqualified instances of True and False
2347 are treated as the standard definitions, regardless of context.
2349 * GDB now parses C++ symbol and type names more flexibly. For
2352 template<typename T> class C { };
2355 GDB will now correctly handle all of:
2357 ptype C<char const *>
2358 ptype C<char const*>
2359 ptype C<const char *>
2360 ptype C<const char*>
2362 * New features in the GDB remote stub, gdbserver
2364 - The "--wrapper" command-line argument tells gdbserver to use a
2365 wrapper program to launch programs for debugging.
2367 - On PowerPC and S/390 targets, it is now possible to use a single
2368 gdbserver executable to debug both 32-bit and 64-bit programs.
2369 (This requires gdbserver itself to be built as a 64-bit executable.)
2371 - gdbserver uses the new noack protocol mode for TCP connections to
2372 reduce communications latency, if also supported and enabled in GDB.
2374 - Support for the sparc64-linux-gnu target is now included in
2377 - The amd64-linux build of gdbserver now supports debugging both
2378 32-bit and 64-bit programs.
2380 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2381 now support hardware watchpoints, and will use them automatically
2386 GDB now has support for scripting using Python. Whether this is
2387 available is determined at configure time.
2389 New GDB commands can now be written in Python.
2391 * Ada tasking support
2393 Ada tasks can now be inspected in GDB. The following commands have
2397 Print the list of Ada tasks.
2399 Print detailed information about task number N.
2401 Print the task number of the current task.
2403 Switch the context of debugging to task number N.
2405 * Support for user-defined prefixed commands. The "define" command can
2406 add new commands to existing prefixes, e.g. "target".
2408 * Multi-inferior, multi-process debugging.
2410 GDB now has generalized support for multi-inferior debugging. See
2411 "Debugging Multiple Inferiors" in the manual for more information.
2412 Although availability still depends on target support, the command
2413 set is more uniform now. The GNU/Linux specific multi-forks support
2414 has been migrated to this new framework. This implied some user
2415 visible changes; see "New commands" and also "Removed commands"
2418 * Target descriptions can now describe the target OS ABI. See the
2419 "Target Description Format" section in the user manual for more
2422 * Target descriptions can now describe "compatible" architectures
2423 to indicate that the target can execute applications for a different
2424 architecture in addition to those for the main target architecture.
2425 See the "Target Description Format" section in the user manual for
2428 * Multi-architecture debugging.
2430 GDB now includes general supports for debugging applications on
2431 hybrid systems that use more than one single processor architecture
2432 at the same time. Each such hybrid architecture still requires
2433 specific support to be added. The only hybrid architecture supported
2434 in this version of GDB is the Cell Broadband Engine.
2436 * GDB now supports integrated debugging of Cell/B.E. applications that
2437 use both the PPU and SPU architectures. To enable support for hybrid
2438 Cell/B.E. debugging, you need to configure GDB to support both the
2439 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2440 --enable-targets configure option.
2442 * Non-stop mode debugging.
2444 For some targets, GDB now supports an optional mode of operation in
2445 which you can examine stopped threads while other threads continue
2446 to execute freely. This is referred to as non-stop mode, with the
2447 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2448 section in the user manual for more information.
2450 To be able to support remote non-stop debugging, a remote stub needs
2451 to implement the non-stop mode remote protocol extensions, as
2452 described in the "Remote Non-Stop" section of the user manual. The
2453 GDB remote stub, gdbserver, has been adjusted to support these
2454 extensions on linux targets.
2456 * New commands (for set/show, see "New options" below)
2458 catch syscall [NAME(S) | NUMBER(S)]
2459 Catch system calls. Arguments, which should be names of system
2460 calls or their numbers, mean catch only those syscalls. Without
2461 arguments, every syscall will be caught. When the inferior issues
2462 any of the specified syscalls, GDB will stop and announce the system
2463 call, both when it is called and when its call returns. This
2464 feature is currently available with a native GDB running on the
2465 Linux Kernel, under the following architectures: x86, x86_64,
2466 PowerPC and PowerPC64.
2468 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2470 Search memory for a sequence of bytes.
2472 maint set python print-stack
2473 maint show python print-stack
2474 Show a stack trace when an error is encountered in a Python script.
2477 Invoke CODE by passing it to the Python interpreter.
2482 These allow macros to be defined, undefined, and listed
2486 Show operating system information about processes.
2489 List the inferiors currently under GDB's control.
2492 Switch focus to inferior number NUM.
2495 Detach from inferior number NUM.
2498 Kill inferior number NUM.
2502 set spu stop-on-load
2503 show spu stop-on-load
2504 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2506 set spu auto-flush-cache
2507 show spu auto-flush-cache
2508 Control whether to automatically flush the software-managed cache
2509 during Cell/B.E. debugging.
2511 set sh calling-convention
2512 show sh calling-convention
2513 Control the calling convention used when calling SH target functions.
2516 show debug timestamp
2517 Control display of timestamps with GDB debugging output.
2519 set disassemble-next-line
2520 show disassemble-next-line
2521 Control display of disassembled source lines or instructions when
2524 set remote noack-packet
2525 show remote noack-packet
2526 Set/show the use of remote protocol QStartNoAckMode packet. See above
2527 under "New remote packets."
2529 set remote query-attached-packet
2530 show remote query-attached-packet
2531 Control use of remote protocol `qAttached' (query-attached) packet.
2533 set remote read-siginfo-object
2534 show remote read-siginfo-object
2535 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2538 set remote write-siginfo-object
2539 show remote write-siginfo-object
2540 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2543 set remote reverse-continue
2544 show remote reverse-continue
2545 Control use of remote protocol 'bc' (reverse-continue) packet.
2547 set remote reverse-step
2548 show remote reverse-step
2549 Control use of remote protocol 'bs' (reverse-step) packet.
2551 set displaced-stepping
2552 show displaced-stepping
2553 Control displaced stepping mode. Displaced stepping is a way to
2554 single-step over breakpoints without removing them from the debuggee.
2555 Also known as "out-of-line single-stepping".
2558 show debug displaced
2559 Control display of debugging info for displaced stepping.
2561 maint set internal-error
2562 maint show internal-error
2563 Control what GDB does when an internal error is detected.
2565 maint set internal-warning
2566 maint show internal-warning
2567 Control what GDB does when an internal warning is detected.
2572 Use a wrapper program to launch programs for debugging.
2574 set multiple-symbols (all|ask|cancel)
2575 show multiple-symbols
2576 The value of this variable can be changed to adjust the debugger behavior
2577 when an expression or a breakpoint location contains an ambiguous symbol
2578 name (an overloaded function name, for instance).
2580 set breakpoint always-inserted
2581 show breakpoint always-inserted
2582 Keep breakpoints always inserted in the target, as opposed to inserting
2583 them when resuming the target, and removing them when the target stops.
2584 This option can improve debugger performance on slow remote targets.
2586 set arm fallback-mode (arm|thumb|auto)
2587 show arm fallback-mode
2588 set arm force-mode (arm|thumb|auto)
2590 These commands control how ARM GDB determines whether instructions
2591 are ARM or Thumb. The default for both settings is auto, which uses
2592 the current CPSR value for instructions without symbols; previous
2593 versions of GDB behaved as if "set arm fallback-mode arm".
2595 set disable-randomization
2596 show disable-randomization
2597 Standalone programs run with the virtual address space randomization enabled
2598 by default on some platforms. This option keeps the addresses stable across
2599 multiple debugging sessions.
2603 Control whether other threads are stopped or not when some thread hits
2608 Requests that asynchronous execution is enabled in the target, if available.
2609 In this case, it's possible to resume target in the background, and interact
2610 with GDB while the target is running. "show target-async" displays the
2611 current state of asynchronous execution of the target.
2613 set target-wide-charset
2614 show target-wide-charset
2615 The target-wide-charset is the name of the character set that GDB
2616 uses when printing characters whose type is wchar_t.
2618 set tcp auto-retry (on|off)
2620 set tcp connect-timeout
2621 show tcp connect-timeout
2622 These commands allow GDB to retry failed TCP connections to a remote stub
2623 with a specified timeout period; this is useful if the stub is launched
2624 in parallel with GDB but may not be ready to accept connections immediately.
2626 set libthread-db-search-path
2627 show libthread-db-search-path
2628 Control list of directories which GDB will search for appropriate
2631 set schedule-multiple (on|off)
2632 show schedule-multiple
2633 Allow GDB to resume all threads of all processes or only threads of
2634 the current process.
2638 Use more aggressive caching for accesses to the stack. This improves
2639 performance of remote debugging (particularly backtraces) without
2640 affecting correctness.
2642 set interactive-mode (on|off|auto)
2643 show interactive-mode
2644 Control whether GDB runs in interactive mode (on) or not (off).
2645 When in interactive mode, GDB waits for the user to answer all
2646 queries. Otherwise, GDB does not wait and assumes the default
2647 answer. When set to auto (the default), GDB determines which
2648 mode to use based on the stdin settings.
2653 For program forks, this is replaced by the new more generic `info
2654 inferiors' command. To list checkpoints, you can still use the
2655 `info checkpoints' command, which was an alias for the `info forks'
2659 Replaced by the new `inferior' command. To switch between
2660 checkpoints, you can still use the `restart' command, which was an
2661 alias for the `fork' command.
2664 This is removed, since some targets don't have a notion of
2665 processes. To switch between processes, you can still use the
2666 `inferior' command using GDB's own inferior number.
2669 For program forks, this is replaced by the new more generic `kill
2670 inferior' command. To delete a checkpoint, you can still use the
2671 `delete checkpoint' command, which was an alias for the `delete
2675 For program forks, this is replaced by the new more generic `detach
2676 inferior' command. To detach a checkpoint, you can still use the
2677 `detach checkpoint' command, which was an alias for the `detach
2680 * New native configurations
2682 x86/x86_64 Darwin i[34567]86-*-darwin*
2684 x86_64 MinGW x86_64-*-mingw*
2688 Lattice Mico32 lm32-*
2689 x86 DICOS i[34567]86-*-dicos*
2690 x86_64 DICOS x86_64-*-dicos*
2693 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2694 (mingw32ce) debugging.
2700 These commands were actually not implemented on any target.
2702 *** Changes in GDB 6.8
2704 * New native configurations
2706 NetBSD/hppa hppa*-*netbsd*
2707 Xtensa GNU/Linux xtensa*-*-linux*
2711 NetBSD/hppa hppa*-*-netbsd*
2712 Xtensa GNU/Lunux xtensa*-*-linux*
2714 * Change in command line behavior -- corefiles vs. process ids.
2716 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2717 attaching to process NUMBER fails, GDB no longer attempts to open a
2718 core file named NUMBER. Attaching to a program using the -c option
2719 is no longer supported. Instead, use the '-p' or '--pid' options.
2721 * GDB can now be built as a native debugger for debugging Windows x86
2722 (mingw32) Portable Executable (PE) programs.
2724 * Pending breakpoints no longer change their number when their address
2727 * GDB now supports breakpoints with multiple locations,
2728 including breakpoints on C++ constructors, inside C++ templates,
2729 and in inlined functions.
2731 * GDB's ability to debug optimized code has been improved. GDB more
2732 accurately identifies function bodies and lexical blocks that occupy
2733 more than one contiguous range of addresses.
2735 * Target descriptions can now describe registers for PowerPC.
2737 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2738 registers on PowerPC targets.
2740 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2741 targets even when the libthread_db library is not available.
2743 * The GDB remote stub, gdbserver, now supports the new file transfer
2744 commands (remote put, remote get, and remote delete).
2746 * The GDB remote stub, gdbserver, now supports run and attach in
2747 extended-remote mode.
2749 * hppa*64*-*-hpux11* target broken
2750 The debugger is unable to start a program and fails with the following
2751 error: "Error trying to get information about dynamic linker".
2752 The gdb-6.7 release is also affected.
2754 * GDB now supports the --enable-targets= configure option to allow
2755 building a single GDB executable that supports multiple remote
2756 target architectures.
2758 * GDB now supports debugging C and C++ programs which use the
2759 Decimal Floating Point extension. In addition, the PowerPC target
2760 now has a set of pseudo-registers to inspect decimal float values
2761 stored in two consecutive float registers.
2763 * The -break-insert MI command can optionally create pending
2766 * Improved support for debugging Ada
2767 Many improvements to the Ada language support have been made. These
2769 - Better support for Ada2005 interface types
2770 - Improved handling of arrays and slices in general
2771 - Better support for Taft-amendment types
2772 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2774 - Improved command completion in Ada
2777 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2782 set print frame-arguments (all|scalars|none)
2783 show print frame-arguments
2784 The value of this variable can be changed to control which argument
2785 values should be printed by the debugger when displaying a frame.
2790 Transfer files to and from a remote target, and delete remote files.
2797 Transfer files to and from a remote target, and delete remote files.
2799 * New remote packets
2806 Open, close, read, write, and delete files on the remote system.
2809 Attach to an existing process on the remote system, in extended-remote
2813 Run a new process on the remote system, in extended-remote mode.
2815 *** Changes in GDB 6.7
2817 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2818 bfd, libiberty and opcodes, as revealed by static analysis donated by
2819 Coverity, Inc. (http://scan.coverity.com).
2821 * When looking up multiply-defined global symbols, GDB will now prefer the
2822 symbol definition in the current shared library if it was built using the
2823 -Bsymbolic linker option.
2825 * When the Text User Interface (TUI) is not configured, GDB will now
2826 recognize the -tui command-line option and print a message that the TUI
2829 * The GDB remote stub, gdbserver, now has lower overhead for high
2830 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2832 * GDB for MIPS targets now autodetects whether a remote target provides
2833 32-bit or 64-bit register values.
2835 * Support for C++ member pointers has been improved.
2837 * GDB now understands XML target descriptions, which specify the
2838 target's overall architecture. GDB can read a description from
2839 a local file or over the remote serial protocol.
2841 * Vectors of single-byte data use a new integer type which is not
2842 automatically displayed as character or string data.
2844 * The /s format now works with the print command. It displays
2845 arrays of single-byte integers and pointers to single-byte integers
2848 * Target descriptions can now describe target-specific registers,
2849 for architectures which have implemented the support (currently
2850 only ARM, M68K, and MIPS).
2852 * GDB and the GDB remote stub, gdbserver, now support the XScale
2855 * The GDB remote stub, gdbserver, has been updated to support
2856 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2857 has been rewritten to use the standard GDB remote protocol.
2859 * GDB can now step into C++ functions which are called through thunks.
2861 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2863 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2864 layout. It also supports a TextSeg= and DataSeg= response when only
2865 segment base addresses (rather than offsets) are available.
2867 * The /i format now outputs any trailing branch delay slot instructions
2868 immediately following the last instruction within the count specified.
2870 * The GDB remote protocol "T" stop reply packet now supports a
2871 "library" response. Combined with the new "qXfer:libraries:read"
2872 packet, this response allows GDB to debug shared libraries on targets
2873 where the operating system manages the list of loaded libraries (e.g.
2874 Windows and SymbianOS).
2876 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2877 (DLLs) on Windows and Windows CE targets.
2879 * GDB now supports a faster verification that a .debug file matches its binary
2880 according to its build-id signature, if the signature is present.
2886 Enable or disable hardware flow control (RTS/CTS) on the serial port
2887 when debugging using remote targets.
2889 set mem inaccessible-by-default
2890 show mem inaccessible-by-default
2891 If the target supplies a memory map, for instance via the remote
2892 protocol's "qXfer:memory-map:read" packet, setting this variable
2893 prevents GDB from accessing memory outside the memory map. This
2894 is useful for targets with memory mapped registers or which react
2895 badly to accesses of unmapped address space.
2897 set breakpoint auto-hw
2898 show breakpoint auto-hw
2899 If the target supplies a memory map, for instance via the remote
2900 protocol's "qXfer:memory-map:read" packet, setting this variable
2901 lets GDB use hardware breakpoints automatically for memory regions
2902 where it can not use software breakpoints. This covers both the
2903 "break" command and internal breakpoints used for other commands
2904 including "next" and "finish".
2907 catch exception unhandled
2908 Stop the program execution when Ada exceptions are raised.
2911 Stop the program execution when an Ada assertion failed.
2915 Set an alternate system root for target files. This is a more
2916 general version of "set solib-absolute-prefix", which is now
2917 an alias to "set sysroot".
2920 Provide extended SPU facility status information. This set of
2921 commands is available only when debugging the Cell/B.E. SPU
2924 * New native configurations
2926 OpenBSD/sh sh*-*openbsd*
2929 unset tdesc filename
2931 Use the specified local file as an XML target description, and do
2932 not query the target for its built-in description.
2936 OpenBSD/sh sh*-*-openbsd*
2937 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2938 Toshiba Media Processor mep-elf
2940 * New remote packets
2943 Ignore the specified signals; pass them directly to the debugged program
2944 without stopping other threads or reporting them to GDB.
2946 qXfer:features:read:
2947 Read an XML target description from the target, which describes its
2952 Read or write contents of an spufs file on the target system. These
2953 packets are available only on the Cell/B.E. SPU architecture.
2955 qXfer:libraries:read:
2956 Report the loaded shared libraries. Combined with new "T" packet
2957 response, this packet allows GDB to debug shared libraries on
2958 targets where the operating system manages the list of loaded
2959 libraries (e.g. Windows and SymbianOS).
2963 Support for these obsolete configurations has been removed.
2971 i[34567]86-*-lynxos*
2972 i[34567]86-*-netware*
2973 i[34567]86-*-sco3.2v5*
2974 i[34567]86-*-sco3.2v4*
2976 i[34567]86-*-sysv4.2*
2979 i[34567]86-*-unixware2*
2980 i[34567]86-*-unixware*
2989 * Other removed features
2996 Various m68k-only ROM monitors.
3003 Various Renesas ROM monitors and debugging interfaces for SH and
3008 Support for a Macraigor serial interface to on-chip debugging.
3009 GDB does not directly support the newer parallel or USB
3014 A debug information format. The predecessor to DWARF 2 and
3015 DWARF 3, which are still supported.
3017 Support for the HP aCC compiler on HP-UX/PA-RISC
3019 SOM-encapsulated symbolic debugging information, automatic
3020 invocation of pxdb, and the aCC custom C++ ABI. This does not
3021 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3022 with aCC can still be debugged on an assembly level.
3024 MIPS ".pdr" sections
3026 A MIPS-specific format used to describe stack frame layout
3027 in debugging information.
3031 GDB could work with an older version of Guile to debug
3032 the interpreter and Scheme programs running in it.
3034 set mips stack-arg-size
3035 set mips saved-gpreg-size
3037 Use "set mips abi" to control parameter passing for MIPS.
3039 *** Changes in GDB 6.6
3044 Cell Broadband Engine SPU spu-elf
3046 * GDB can now be configured as a cross-debugger targeting native Windows
3047 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3048 running on a Windows system over TCP/IP to debug Windows programs.
3050 * The GDB remote stub, gdbserver, has been updated to support Windows and
3051 Cygwin debugging. Both single-threaded and multi-threaded programs are
3054 * The "set trust-readonly-sections" command works again. This command was
3055 broken in GDB 6.3, 6.4, and 6.5.
3057 * The "load" command now supports writing to flash memory, if the remote
3058 stub provides the required support.
3060 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3061 longer requires symbolic debug information (e.g. DWARF-2).
3066 unset substitute-path
3067 show substitute-path
3068 Manage a list of substitution rules that GDB uses to rewrite the name
3069 of the directories where the sources are located. This can be useful
3070 for instance when the sources were moved to a different location
3071 between compilation and debugging.
3075 Print each CLI command as it is executed. Each command is prefixed with
3076 a number of `+' symbols representing the nesting depth.
3077 The source command now has a `-v' option to enable the same feature.
3081 The ARM Demon monitor support (RDP protocol, "target rdp").
3083 Kernel Object Display, an embedded debugging feature which only worked with
3084 an obsolete version of Cisco IOS.
3086 The 'set download-write-size' and 'show download-write-size' commands.
3088 * New remote packets
3091 Tell a stub about GDB client features, and request remote target features.
3092 The first feature implemented is PacketSize, which allows the target to
3093 specify the size of packets it can handle - to minimize the number of
3094 packets required and improve performance when connected to a remote
3098 Fetch an OS auxilliary vector from the remote stub. This packet is a
3099 more efficient replacement for qPart:auxv:read.
3101 qXfer:memory-map:read:
3102 Fetch a memory map from the remote stub, including information about
3103 RAM, ROM, and flash memory devices.
3108 Erase and program a flash memory device.
3110 * Removed remote packets
3113 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3114 used it, and only gdbserver implemented it.
3116 *** Changes in GDB 6.5
3120 Renesas M32C/M16C m32c-elf
3122 Morpho Technologies ms1 ms1-elf
3126 init-if-undefined Initialize a convenience variable, but
3127 only if it doesn't already have a value.
3129 The following commands are presently only implemented for native GNU/Linux:
3131 checkpoint Save a snapshot of the program state.
3133 restart <n> Return the program state to a
3134 previously saved state.
3136 info checkpoints List currently saved checkpoints.
3138 delete-checkpoint <n> Delete a previously saved checkpoint.
3140 set|show detach-on-fork Tell gdb whether to detach from a newly
3141 forked process, or to keep debugging it.
3143 info forks List forks of the user program that
3144 are available to be debugged.
3146 fork <n> Switch to debugging one of several
3147 forks of the user program that are
3148 available to be debugged.
3150 delete-fork <n> Delete a fork from the list of forks
3151 that are available to be debugged (and
3152 kill the forked process).
3154 detach-fork <n> Delete a fork from the list of forks
3155 that are available to be debugged (and
3156 allow the process to continue).
3160 Morpho Technologies ms2 ms1-elf
3162 * Improved Windows host support
3164 GDB now builds as a cross debugger hosted on i686-mingw32, including
3165 native console support, and remote communications using either
3166 network sockets or serial ports.
3168 * Improved Modula-2 language support
3170 GDB can now print most types in the Modula-2 syntax. This includes:
3171 basic types, set types, record types, enumerated types, range types,
3172 pointer types and ARRAY types. Procedure var parameters are correctly
3173 printed and hexadecimal addresses and character constants are also
3174 written in the Modula-2 syntax. Best results can be obtained by using
3175 GNU Modula-2 together with the -gdwarf-2 command line option.
3179 The ARM rdi-share module.
3181 The Netware NLM debug server.
3183 *** Changes in GDB 6.4
3185 * New native configurations
3187 OpenBSD/arm arm*-*-openbsd*
3188 OpenBSD/mips64 mips64-*-openbsd*
3192 Morpho Technologies ms1 ms1-elf
3194 * New command line options
3196 --batch-silent As for --batch, but totally silent.
3197 --return-child-result The debugger will exist with the same value
3198 the child (debugged) program exited with.
3199 --eval-command COMMAND, -ex COMMAND
3200 Execute a single GDB CLI command. This may be
3201 specified multiple times and in conjunction
3202 with the --command (-x) option.
3204 * Deprecated commands removed
3206 The following commands, that were deprecated in 2000, have been
3210 set|show arm disassembly-flavor set|show arm disassembler
3211 othernames set arm disassembler
3212 set|show remotedebug set|show debug remote
3213 set|show archdebug set|show debug arch
3214 set|show eventdebug set|show debug event
3217 * New BSD user-level threads support
3219 It is now possible to debug programs using the user-level threads
3220 library on OpenBSD and FreeBSD. Currently supported (target)
3223 FreeBSD/amd64 x86_64-*-freebsd*
3224 FreeBSD/i386 i386-*-freebsd*
3225 OpenBSD/i386 i386-*-openbsd*
3227 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3228 are not yet supported.
3230 * New support for Matsushita MN10300 w/sim added
3231 (Work in progress). mn10300-elf.
3233 * REMOVED configurations and files
3235 VxWorks and the XDR protocol *-*-vxworks
3236 Motorola MCORE mcore-*-*
3237 National Semiconductor NS32000 ns32k-*-*
3239 * New "set print array-indexes" command
3241 After turning this setting "on", GDB prints the index of each element
3242 when displaying arrays. The default is "off" to preserve the previous
3245 * VAX floating point support
3247 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3249 * User-defined command support
3251 In addition to using $arg0..$arg9 for argument passing, it is now possible
3252 to use $argc to determine now many arguments have been passed. See the
3253 section on user-defined commands in the user manual for more information.
3255 *** Changes in GDB 6.3:
3257 * New command line option
3259 GDB now accepts -l followed by a number to set the timeout for remote
3262 * GDB works with GCC -feliminate-dwarf2-dups
3264 GDB now supports a more compact representation of DWARF-2 debug
3265 information using DW_FORM_ref_addr references. These are produced
3266 by GCC with the option -feliminate-dwarf2-dups and also by some
3267 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3268 to use -feliminate-dwarf2-dups.
3270 * Internationalization
3272 When supported by the host system, GDB will be built with
3273 internationalization (libintl). The task of marking up the sources is
3274 continued, we're looking forward to our first translation.
3278 Initial support for debugging programs compiled with the GNAT
3279 implementation of the Ada programming language has been integrated
3280 into GDB. In this release, support is limited to expression evaluation.
3282 * New native configurations
3284 GNU/Linux/m32r m32r-*-linux-gnu
3288 GDB's remote protocol now includes support for the 'p' packet. This
3289 packet is used to fetch individual registers from a remote inferior.
3291 * END-OF-LIFE registers[] compatibility module
3293 GDB's internal register infrastructure has been completely rewritten.
3294 The new infrastructure making possible the implementation of key new
3295 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3298 GDB 6.3 will be the last release to include the the registers[]
3299 compatibility module that allowed out-of-date configurations to
3300 continue to work. This change directly impacts the following
3310 powerpc bdm protocol
3312 Unless there is activity to revive these configurations, they will be
3313 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3315 * OBSOLETE configurations and files
3317 Configurations that have been declared obsolete in this release have
3318 been commented out. Unless there is activity to revive these
3319 configurations, the next release of GDB will have their sources
3320 permanently REMOVED.
3329 *** Changes in GDB 6.2.1:
3331 * MIPS `break main; run' gave an heuristic-fence-post warning
3333 When attempting to run even a simple program, a warning about
3334 heuristic-fence-post being hit would be reported. This problem has
3337 * MIPS IRIX 'long double' crashed GDB
3339 When examining a long double variable, GDB would get a segmentation
3340 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3341 IRIX long double values).
3345 A bug in the VAX stack code was causing problems with the "next"
3346 command. This problem has been fixed.
3348 *** Changes in GDB 6.2:
3350 * Fix for ``many threads''
3352 On GNU/Linux systems that use the NPTL threads library, a program
3353 rapidly creating and deleting threads would confuse GDB leading to the
3356 ptrace: No such process.
3357 thread_db_get_info: cannot get thread info: generic error
3359 This problem has been fixed.
3361 * "-async" and "-noasync" options removed.
3363 Support for the broken "-noasync" option has been removed (it caused
3366 * New ``start'' command.
3368 This command runs the program until the begining of the main procedure.
3370 * New BSD Kernel Data Access Library (libkvm) interface
3372 Using ``target kvm'' it is now possible to debug kernel core dumps and
3373 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3374 platforms. Currently supported (native-only) configurations are:
3376 FreeBSD/amd64 x86_64-*-freebsd*
3377 FreeBSD/i386 i?86-*-freebsd*
3378 NetBSD/i386 i?86-*-netbsd*
3379 NetBSD/m68k m68*-*-netbsd*
3380 NetBSD/sparc sparc-*-netbsd*
3381 OpenBSD/amd64 x86_64-*-openbsd*
3382 OpenBSD/i386 i?86-*-openbsd*
3383 OpenBSD/m68k m68*-openbsd*
3384 OpenBSD/sparc sparc-*-openbsd*
3386 * Signal trampoline code overhauled
3388 Many generic problems with GDB's signal handling code have been fixed.
3389 These include: backtraces through non-contiguous stacks; recognition
3390 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3391 call; backtrace through a signal trampoline; step into and out of
3392 signal handlers; and single-stepping in the signal trampoline.
3394 Please note that kernel bugs are a limiting factor here. These
3395 features have been shown to work on an s390 GNU/Linux system that
3396 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3398 * Cygwin support for DWARF 2 added.
3400 * New native configurations
3402 GNU/Linux/hppa hppa*-*-linux*
3403 OpenBSD/hppa hppa*-*-openbsd*
3404 OpenBSD/m68k m68*-*-openbsd*
3405 OpenBSD/m88k m88*-*-openbsd*
3406 OpenBSD/powerpc powerpc-*-openbsd*
3407 NetBSD/vax vax-*-netbsd*
3408 OpenBSD/vax vax-*-openbsd*
3410 * END-OF-LIFE frame compatibility module
3412 GDB's internal frame infrastructure has been completely rewritten.
3413 The new infrastructure making it possible to support key new features
3414 including DWARF 2 Call Frame Information. To aid in the task of
3415 migrating old configurations to this new infrastructure, a
3416 compatibility module, that allowed old configurations to continue to
3417 work, was also included.
3419 GDB 6.2 will be the last release to include this frame compatibility
3420 module. This change directly impacts the following configurations:
3430 Unless there is activity to revive these configurations, they will be
3431 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3433 * REMOVED configurations and files
3435 Sun 3, running SunOS 3 m68*-*-sunos3*
3436 Sun 3, running SunOS 4 m68*-*-sunos4*
3437 Sun 2, running SunOS 3 m68000-*-sunos3*
3438 Sun 2, running SunOS 4 m68000-*-sunos4*
3439 Motorola 680x0 running LynxOS m68*-*-lynxos*
3440 AT&T 3b1/Unix pc m68*-att-*
3441 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3442 decstation mips-dec-* mips-little-*
3443 riscos mips-*-riscos* mips-*-sysv*
3444 sonymips mips-sony-*
3445 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3447 *** Changes in GDB 6.1.1:
3449 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3451 The TUI (Text-mode User Interface) is now built as part of a default
3452 GDB configuration. It is enabled by either selecting the TUI with the
3453 command line option "-i=tui" or by running the separate "gdbtui"
3454 program. For more information on the TUI, see the manual "Debugging
3457 * Pending breakpoint support (also included in GDB 6.1)
3459 Support has been added to allow you to specify breakpoints in shared
3460 libraries that have not yet been loaded. If a breakpoint location
3461 cannot be found, and the "breakpoint pending" option is set to auto,
3462 GDB queries you if you wish to make the breakpoint pending on a future
3463 shared-library load. If and when GDB resolves the breakpoint symbol,
3464 the pending breakpoint is removed as one or more regular breakpoints
3467 Pending breakpoints are very useful for GCJ Java debugging.
3469 * Fixed ISO-C build problems
3471 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3472 non ISO-C code that stopped them being built using a more strict ISO-C
3473 compiler (e.g., IBM's C compiler).
3475 * Fixed build problem on IRIX 5
3477 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3478 wasn't able to compile compile on an IRIX 5 system.
3480 * Added execute permission to gdb/gdbserver/configure
3482 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3483 permission. This bug would cause configure to fail on a number of
3484 systems (Solaris, IRIX). Ref: server/519.
3486 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3488 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3489 has been updated to use constant array sizes.
3491 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3493 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3494 its generated DWARF Call Frame Info. This encoding was causing GDB to
3495 panic, that panic has been fixed. Ref: gdb/1628.
3497 * Fixed a problem when examining parameters in shared library code.
3499 When examining parameters in optimized shared library code generated
3500 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3501 not available''. GDB now correctly displays the variable's value.
3503 *** Changes in GDB 6.1:
3505 * Removed --with-mmalloc
3507 Support for the mmalloc memory manager has been removed, as it
3508 conflicted with the internal gdb byte cache.
3510 * Changes in AMD64 configurations
3512 The AMD64 target now includes the %cs and %ss registers. As a result
3513 the AMD64 remote protocol has changed; this affects the floating-point
3514 and SSE registers. If you rely on those registers for your debugging,
3515 you should upgrade gdbserver on the remote side.
3517 * Revised SPARC target
3519 The SPARC target has been completely revised, incorporating the
3520 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3521 support for LynxOS and SunOS 4 has been dropped. Calling functions
3522 from within GDB on operating systems with a non-executable stack
3523 (Solaris, OpenBSD) now works.
3527 GDB has a new C++ demangler which does a better job on the mangled
3528 names generated by current versions of g++. It also runs faster, so
3529 with this and other changes gdb should now start faster on large C++
3532 * DWARF 2 Location Expressions
3534 GDB support for location expressions has been extended to support function
3535 arguments and frame bases. Older versions of GDB could crash when they
3538 * C++ nested types and namespaces
3540 GDB's support for nested types and namespaces in C++ has been
3541 improved, especially if you use the DWARF 2 debugging format. (This
3542 is the default for recent versions of GCC on most platforms.)
3543 Specifically, if you have a class "Inner" defined within a class or
3544 namespace "Outer", then GDB realizes that the class's name is
3545 "Outer::Inner", not simply "Inner". This should greatly reduce the
3546 frequency of complaints about not finding RTTI symbols. In addition,
3547 if you are stopped at inside of a function defined within a namespace,
3548 GDB modifies its name lookup accordingly.
3550 * New native configurations
3552 NetBSD/amd64 x86_64-*-netbsd*
3553 OpenBSD/amd64 x86_64-*-openbsd*
3554 OpenBSD/alpha alpha*-*-openbsd*
3555 OpenBSD/sparc sparc-*-openbsd*
3556 OpenBSD/sparc64 sparc64-*-openbsd*
3558 * New debugging protocols
3560 M32R with SDI protocol m32r-*-elf*
3562 * "set prompt-escape-char" command deleted.
3564 The command "set prompt-escape-char" has been deleted. This command,
3565 and its very obscure effet on GDB's prompt, was never documented,
3566 tested, nor mentioned in the NEWS file.
3568 * OBSOLETE configurations and files
3570 Configurations that have been declared obsolete in this release have
3571 been commented out. Unless there is activity to revive these
3572 configurations, the next release of GDB will have their sources
3573 permanently REMOVED.
3575 Sun 3, running SunOS 3 m68*-*-sunos3*
3576 Sun 3, running SunOS 4 m68*-*-sunos4*
3577 Sun 2, running SunOS 3 m68000-*-sunos3*
3578 Sun 2, running SunOS 4 m68000-*-sunos4*
3579 Motorola 680x0 running LynxOS m68*-*-lynxos*
3580 AT&T 3b1/Unix pc m68*-att-*
3581 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3582 decstation mips-dec-* mips-little-*
3583 riscos mips-*-riscos* mips-*-sysv*
3584 sonymips mips-sony-*
3585 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3587 * REMOVED configurations and files
3589 SGI Irix-4.x mips-sgi-irix4 or iris4
3590 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3591 Z8000 simulator z8k-zilog-none or z8ksim
3592 Matsushita MN10200 w/simulator mn10200-*-*
3593 H8/500 simulator h8500-hitachi-hms or h8500hms
3594 HP/PA running BSD hppa*-*-bsd*
3595 HP/PA running OSF/1 hppa*-*-osf*
3596 HP/PA Pro target hppa*-*-pro*
3597 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3598 386BSD i[3456]86-*-bsd*
3599 Sequent family i[3456]86-sequent-sysv4*
3600 i[3456]86-sequent-sysv*
3601 i[3456]86-sequent-bsd*
3602 SPARC running LynxOS sparc-*-lynxos*
3603 SPARC running SunOS 4 sparc-*-sunos4*
3604 Tsqware Sparclet sparclet-*-*
3605 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3607 *** Changes in GDB 6.0:
3611 Support for debugging the Objective-C programming language has been
3612 integrated into GDB.
3614 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3616 DWARF 2's Call Frame Information makes available compiler generated
3617 information that more exactly describes the program's run-time stack.
3618 By using this information, GDB is able to provide more robust stack
3621 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3622 have been updated to use a new backtrace mechanism which includes
3623 DWARF 2 CFI support.
3627 GDB's remote protocol has been extended to include support for hosted
3628 file I/O (where the remote target uses GDB's file system). See GDB's
3629 remote protocol documentation for details.
3631 * All targets using the new architecture framework.
3633 All of GDB's targets have been updated to use the new internal
3634 architecture framework. The way is now open for future GDB releases
3635 to include cross-architecture native debugging support (i386 on amd64,
3638 * GNU/Linux's Thread Local Storage (TLS)
3640 GDB now includes support for for the GNU/Linux implementation of
3641 per-thread variables.
3643 * GNU/Linux's Native POSIX Thread Library (NPTL)
3645 GDB's thread code has been updated to work with either the new
3646 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3648 * Separate debug info.
3650 GDB, in conjunction with BINUTILS, now supports a mechanism for
3651 automatically loading debug information from a separate file. Instead
3652 of shipping full debug and non-debug versions of system libraries,
3653 system integrators can now instead ship just the stripped libraries
3654 and optional debug files.
3656 * DWARF 2 Location Expressions
3658 DWARF 2 Location Expressions allow the compiler to more completely
3659 describe the location of variables (even in optimized code) to the
3662 GDB now includes preliminary support for location expressions (support
3663 for DW_OP_piece is still missing).
3667 A number of long standing bugs that caused GDB to die while starting a
3668 Java application have been fixed. GDB's Java support is now
3669 considered "useable".
3671 * GNU/Linux support for fork, vfork, and exec.
3673 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3674 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3677 * GDB supports logging output to a file
3679 There are two new commands, "set logging" and "show logging", which can be
3680 used to capture GDB's output to a file.
3682 * The meaning of "detach" has changed for gdbserver
3684 The "detach" command will now resume the application, as documented. To
3685 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3688 * d10v, m68hc11 `regs' command deprecated
3690 The `info registers' command has been updated so that it displays the
3691 registers using a format identical to the old `regs' command.
3695 A new command, "maint set profile on/off", has been added. This command can
3696 be used to enable or disable profiling while running GDB, to profile a
3697 session or a set of commands. In addition there is a new configure switch,
3698 "--enable-profiling", which will cause GDB to be compiled with profiling
3699 data, for more informative profiling results.
3701 * Default MI syntax changed to "mi2".
3703 The default MI (machine interface) syntax, enabled by the command line
3704 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3705 "mi1", can be enabled by specifying the option "-i=mi1".
3707 Support for the original "mi0" syntax (included in GDB 5.0) has been
3710 Fix for gdb/192: removed extraneous space when displaying frame level.
3711 Fix for gdb/672: update changelist is now output in mi list format.
3712 Fix for gdb/702: a -var-assign that updates the value now shows up
3713 in a subsequent -var-update.
3715 * New native configurations.
3717 FreeBSD/amd64 x86_64-*-freebsd*
3719 * Multi-arched targets.
3721 HP/PA HPUX11 hppa*-*-hpux*
3722 Renesas M32R/D w/simulator m32r-*-elf*
3724 * OBSOLETE configurations and files
3726 Configurations that have been declared obsolete in this release have
3727 been commented out. Unless there is activity to revive these
3728 configurations, the next release of GDB will have their sources
3729 permanently REMOVED.
3731 Z8000 simulator z8k-zilog-none or z8ksim
3732 Matsushita MN10200 w/simulator mn10200-*-*
3733 H8/500 simulator h8500-hitachi-hms or h8500hms
3734 HP/PA running BSD hppa*-*-bsd*
3735 HP/PA running OSF/1 hppa*-*-osf*
3736 HP/PA Pro target hppa*-*-pro*
3737 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3738 Sequent family i[3456]86-sequent-sysv4*
3739 i[3456]86-sequent-sysv*
3740 i[3456]86-sequent-bsd*
3741 Tsqware Sparclet sparclet-*-*
3742 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3744 * REMOVED configurations and files
3747 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3748 IBM AIX PS/2 i[3456]86-*-aix
3749 i386 running Mach 3.0 i[3456]86-*-mach3*
3750 i386 running Mach i[3456]86-*-mach*
3751 i386 running OSF/1 i[3456]86-*osf1mk*
3752 HP/Apollo 68k Family m68*-apollo*-sysv*,
3754 m68*-hp-bsd*, m68*-hp-hpux*
3755 Argonaut Risc Chip (ARC) arc-*-*
3756 Mitsubishi D30V d30v-*-*
3757 Fujitsu FR30 fr30-*-elf*
3758 OS/9000 i[34]86-*-os9k
3759 I960 with MON960 i960-*-coff
3761 * MIPS $fp behavior changed
3763 The convenience variable $fp, for the MIPS, now consistently returns
3764 the address of the current frame's base. Previously, depending on the
3765 context, $fp could refer to either $sp or the current frame's base
3766 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3767 The GNU Source-Level Debugger''.
3769 *** Changes in GDB 5.3:
3771 * GNU/Linux shared library multi-threaded performance improved.
3773 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3774 `/proc', in preference to `ptrace' for memory reads. This may result
3775 in an improvement in the start-up time of multi-threaded, shared
3776 library applications when run under GDB. One GDB user writes: ``loads
3777 shared libs like mad''.
3779 * ``gdbserver'' now supports multi-threaded applications on some targets
3781 Support for debugging multi-threaded applications which use
3782 the GNU/Linux LinuxThreads package has been added for
3783 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3784 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3786 * GDB now supports C/C++ preprocessor macros.
3788 GDB now expands preprocessor macro invocations in C/C++ expressions,
3789 and provides various commands for showing macro definitions and how
3792 The new command `macro expand EXPRESSION' expands any macro
3793 invocations in expression, and shows the result.
3795 The new command `show macro MACRO-NAME' shows the definition of the
3796 macro named MACRO-NAME, and where it was defined.
3798 Most compilers don't include information about macros in the debugging
3799 information by default. In GCC 3.1, for example, you need to compile
3800 your program with the options `-gdwarf-2 -g3'. If the macro
3801 information is present in the executable, GDB will read it.
3803 * Multi-arched targets.
3805 DEC Alpha (partial) alpha*-*-*
3806 DEC VAX (partial) vax-*-*
3808 National Semiconductor NS32000 (partial) ns32k-*-*
3809 Motorola 68000 (partial) m68k-*-*
3810 Motorola MCORE mcore-*-*
3814 Fujitsu FRV architecture added by Red Hat frv*-*-*
3817 * New native configurations
3819 Alpha NetBSD alpha*-*-netbsd*
3820 SH NetBSD sh*-*-netbsdelf*
3821 MIPS NetBSD mips*-*-netbsd*
3822 UltraSPARC NetBSD sparc64-*-netbsd*
3824 * OBSOLETE configurations and files
3826 Configurations that have been declared obsolete in this release have
3827 been commented out. Unless there is activity to revive these
3828 configurations, the next release of GDB will have their sources
3829 permanently REMOVED.
3831 Mitsubishi D30V d30v-*-*
3832 OS/9000 i[34]86-*-os9k
3833 IBM AIX PS/2 i[3456]86-*-aix
3834 Fujitsu FR30 fr30-*-elf*
3835 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3836 Argonaut Risc Chip (ARC) arc-*-*
3837 i386 running Mach 3.0 i[3456]86-*-mach3*
3838 i386 running Mach i[3456]86-*-mach*
3839 i386 running OSF/1 i[3456]86-*osf1mk*
3840 HP/Apollo 68k Family m68*-apollo*-sysv*,
3842 m68*-hp-bsd*, m68*-hp-hpux*
3843 I960 with MON960 i960-*-coff
3845 * OBSOLETE languages
3847 CHILL, a Pascal like language used by telecommunications companies.
3849 * REMOVED configurations and files
3851 AMD 29k family via UDI a29k-amd-udi, udi29k
3852 A29K VxWorks a29k-*-vxworks
3853 AMD 29000 embedded, using EBMON a29k-none-none
3854 AMD 29000 embedded with COFF a29k-none-coff
3855 AMD 29000 embedded with a.out a29k-none-aout
3857 testsuite/gdb.hp/gdb.threads-hp/ directory
3859 * New command "set max-user-call-depth <nnn>"
3861 This command allows the user to limit the call depth of user-defined
3862 commands. The default is 1024.
3864 * Changes in FreeBSD/i386 native debugging.
3866 Support for the "generate-core-file" has been added.
3868 * New commands "dump", "append", and "restore".
3870 These commands allow data to be copied from target memory
3871 to a bfd-format or binary file (dump and append), and back
3872 from a file into memory (restore).
3874 * Improved "next/step" support on multi-processor Alpha Tru64.
3876 The previous single-step mechanism could cause unpredictable problems,
3877 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3878 of a software single-step mechanism prevents this.
3880 *** Changes in GDB 5.2.1:
3888 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3889 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3890 Fix, by Joel Brobecker imported from mainline.
3892 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3893 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3894 Fix, by Fred Fish, imported from mainline.
3896 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3897 Surprisingly enough, it works now.
3898 By Michal Ludvig, imported from mainline.
3900 i386 hardware watchpoint support:
3901 avoid misses on second run for some targets.
3902 By Pierre Muller, imported from mainline.
3904 *** Changes in GDB 5.2:
3906 * New command "set trust-readonly-sections on[off]".
3908 This command is a hint that tells gdb that read-only sections
3909 really are read-only (ie. that their contents will not change).
3910 In this mode, gdb will go to the object file rather than the
3911 target to read memory from read-only sections (such as ".text").
3912 This can be a significant performance improvement on some
3913 (notably embedded) targets.
3915 * New command "generate-core-file" (or "gcore").
3917 This new gdb command allows the user to drop a core file of the child
3918 process state at any time. So far it's been implemented only for
3919 GNU/Linux and Solaris, but should be relatively easily ported to other
3920 hosts. Argument is core file name (defaults to core.<pid>).
3922 * New command line option
3924 GDB now accepts --pid or -p followed by a process id.
3926 * Change in command line behavior -- corefiles vs. process ids.
3928 There is a subtle behavior in the way in which GDB handles
3929 command line arguments. The first non-flag argument is always
3930 a program to debug, but the second non-flag argument may either
3931 be a corefile or a process id. Previously, GDB would attempt to
3932 open the second argument as a corefile, and if that failed, would
3933 issue a superfluous error message and then attempt to attach it as
3934 a process. Now, if the second argument begins with a non-digit,
3935 it will be treated as a corefile. If it begins with a digit,
3936 GDB will attempt to attach it as a process, and if no such process
3937 is found, will then attempt to open it as a corefile.
3939 * Changes in ARM configurations.
3941 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3942 configuration is fully multi-arch.
3944 * New native configurations
3946 ARM NetBSD arm*-*-netbsd*
3947 x86 OpenBSD i[3456]86-*-openbsd*
3948 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3949 Sparc64 running FreeBSD sparc64-*-freebsd*
3953 Sanyo XStormy16 xstormy16-elf
3955 * OBSOLETE configurations and files
3957 Configurations that have been declared obsolete in this release have
3958 been commented out. Unless there is activity to revive these
3959 configurations, the next release of GDB will have their sources
3960 permanently REMOVED.
3962 AMD 29k family via UDI a29k-amd-udi, udi29k
3963 A29K VxWorks a29k-*-vxworks
3964 AMD 29000 embedded, using EBMON a29k-none-none
3965 AMD 29000 embedded with COFF a29k-none-coff
3966 AMD 29000 embedded with a.out a29k-none-aout
3968 testsuite/gdb.hp/gdb.threads-hp/ directory
3970 * REMOVED configurations and files
3972 TI TMS320C80 tic80-*-*
3974 PowerPC Solaris powerpcle-*-solaris*
3975 PowerPC Windows NT powerpcle-*-cygwin32
3976 PowerPC Netware powerpc-*-netware*
3977 Harris/CXUX m88k m88*-harris-cxux*
3978 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3979 ns32k-utek-sysv* ns32k-utek-*
3980 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3981 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3982 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3983 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3984 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3986 * Changes to command line processing
3988 The new `--args' feature can be used to specify command-line arguments
3989 for the inferior from gdb's command line.
3991 * Changes to key bindings
3993 There is a new `operate-and-get-next' function bound to `C-o'.
3995 *** Changes in GDB 5.1.1
3997 Fix compile problem on DJGPP.
3999 Fix a problem with floating-point registers on the i386 being
4002 Fix to stop GDB crashing on .debug_str debug info.
4004 Numerous documentation fixes.
4006 Numerous testsuite fixes.
4008 *** Changes in GDB 5.1:
4010 * New native configurations
4012 Alpha FreeBSD alpha*-*-freebsd*
4013 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4014 MIPS GNU/Linux mips*-*-linux*
4015 MIPS SGI Irix 6.x mips*-sgi-irix6*
4016 ia64 AIX ia64-*-aix*
4017 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4021 Motorola 68HC11 and 68HC12 m68hc11-elf
4023 UltraSparc running GNU/Linux sparc64-*-linux*
4025 * OBSOLETE configurations and files
4027 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4028 Harris/CXUX m88k m88*-harris-cxux*
4029 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4030 ns32k-utek-sysv* ns32k-utek-*
4031 TI TMS320C80 tic80-*-*
4033 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4034 PowerPC Solaris powerpcle-*-solaris*
4035 PowerPC Windows NT powerpcle-*-cygwin32
4036 PowerPC Netware powerpc-*-netware*
4037 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4038 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4039 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4040 Apple Macintosh (MPW) host N/A
4042 stuff.c (Program to stuff files into a specially prepared space in kdb)
4043 kdb-start.c (Main loop for the standalone kernel debugger)
4045 Configurations that have been declared obsolete in this release have
4046 been commented out. Unless there is activity to revive these
4047 configurations, the next release of GDB will have their sources
4048 permanently REMOVED.
4050 * REMOVED configurations and files
4052 Altos 3068 m68*-altos-*
4053 Convex c1-*-*, c2-*-*
4055 ARM RISCix arm-*-* (as host)
4059 * GDB has been converted to ISO C.
4061 GDB's source code has been converted to ISO C. In particular, the
4062 sources are fully protoized, and rely on standard headers being
4067 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4069 * The MI enabled by default.
4071 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4072 revised and enabled by default. Packages which use GDB as a debugging
4073 engine behind a UI or another front end are encouraged to switch to
4074 using the GDB/MI interface, instead of the old annotations interface
4075 which is now deprecated.
4077 * Support for debugging Pascal programs.
4079 GDB now includes support for debugging Pascal programs. The following
4080 main features are supported:
4082 - Pascal-specific data types such as sets;
4084 - automatic recognition of Pascal sources based on file-name
4087 - Pascal-style display of data types, variables, and functions;
4089 - a Pascal expression parser.
4091 However, some important features are not yet supported.
4093 - Pascal string operations are not supported at all;
4095 - there are some problems with boolean types;
4097 - Pascal type hexadecimal constants are not supported
4098 because they conflict with the internal variables format;
4100 - support for Pascal objects and classes is not full yet;
4102 - unlike Pascal, GDB is case-sensitive for symbol names.
4104 * Changes in completion.
4106 Commands such as `shell', `run' and `set args', which pass arguments
4107 to inferior programs, now complete on file names, similar to what
4108 users expect at the shell prompt.
4110 Commands which accept locations, such as `disassemble', `print',
4111 `breakpoint', `until', etc. now complete on filenames as well as
4112 program symbols. Thus, if you type "break foob TAB", and the source
4113 files linked into the programs include `foobar.c', that file name will
4114 be one of the candidates for completion. However, file names are not
4115 considered for completion after you typed a colon that delimits a file
4116 name from a name of a function in that file, as in "break foo.c:bar".
4118 `set demangle-style' completes on available demangling styles.
4120 * New platform-independent commands:
4122 It is now possible to define a post-hook for a command as well as a
4123 hook that runs before the command. For more details, see the
4124 documentation of `hookpost' in the GDB manual.
4126 * Changes in GNU/Linux native debugging.
4128 Support for debugging multi-threaded programs has been completely
4129 revised for all platforms except m68k and sparc. You can now debug as
4130 many threads as your system allows you to have.
4132 Attach/detach is supported for multi-threaded programs.
4134 Support for SSE registers was added for x86. This doesn't work for
4135 multi-threaded programs though.
4137 * Changes in MIPS configurations.
4139 Multi-arch support is enabled for all MIPS configurations.
4141 GDB can now be built as native debugger on SGI Irix 6.x systems for
4142 debugging n32 executables. (Debugging 64-bit executables is not yet
4145 * Unified support for hardware watchpoints in all x86 configurations.
4147 Most (if not all) native x86 configurations support hardware-assisted
4148 breakpoints and watchpoints in a unified manner. This support
4149 implements debug register sharing between watchpoints, which allows to
4150 put a virtually infinite number of watchpoints on the same address,
4151 and also supports watching regions up to 16 bytes with several debug
4154 The new maintenance command `maintenance show-debug-regs' toggles
4155 debugging print-outs in functions that insert, remove, and test
4156 watchpoints and hardware breakpoints.
4158 * Changes in the DJGPP native configuration.
4160 New command ``info dos sysinfo'' displays assorted information about
4161 the CPU, OS, memory, and DPMI server.
4163 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4164 display information about segment descriptors stored in GDT, LDT, and
4167 New commands ``info dos pde'' and ``info dos pte'' display entries
4168 from Page Directory and Page Tables (for now works with CWSDPMI only).
4169 New command ``info dos address-pte'' displays the Page Table entry for
4170 a given linear address.
4172 GDB can now pass command lines longer than 126 characters to the
4173 program being debugged (requires an update to the libdbg.a library
4174 which is part of the DJGPP development kit).
4176 DWARF2 debug info is now supported.
4178 It is now possible to `step' and `next' through calls to `longjmp'.
4180 * Changes in documentation.
4182 All GDB documentation was converted to GFDL, the GNU Free
4183 Documentation License.
4185 Tracepoints-related commands are now fully documented in the GDB
4188 TUI, the Text-mode User Interface, is now documented in the manual.
4190 Tracepoints-related commands are now fully documented in the GDB
4193 The "GDB Internals" manual now has an index. It also includes
4194 documentation of `ui_out' functions, GDB coding standards, x86
4195 hardware watchpoints, and memory region attributes.
4197 * GDB's version number moved to ``version.in''
4199 The Makefile variable VERSION has been replaced by the file
4200 ``version.in''. People creating GDB distributions should update the
4201 contents of this file.
4205 GUD support is now a standard part of the EMACS distribution.
4207 *** Changes in GDB 5.0:
4209 * Improved support for debugging FP programs on x86 targets
4211 Unified and much-improved support for debugging floating-point
4212 programs on all x86 targets. In particular, ``info float'' now
4213 displays the FP registers in the same format on all x86 targets, with
4214 greater level of detail.
4216 * Improvements and bugfixes in hardware-assisted watchpoints
4218 It is now possible to watch array elements, struct members, and
4219 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4220 on x86 targets no longer erroneously trigger when the address is
4223 * Improvements in the native DJGPP version of GDB
4225 The distribution now includes all the scripts and auxiliary files
4226 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4227 machines ``out of the box''.
4229 The DJGPP version can now debug programs that use signals. It is
4230 possible to catch signals that happened in the debuggee, deliver
4231 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4232 would kill the program being debugged.) Programs that hook hardware
4233 interrupts (keyboard, timer, etc.) can also be debugged.
4235 It is now possible to debug DJGPP programs that redirect their
4236 standard handles or switch them to raw (as opposed to cooked) mode, or
4237 even close them. The command ``run < foo > bar'' works as expected,
4238 and ``info terminal'' reports useful information about the debuggee's
4239 terminal, including raw/cooked mode, redirection, etc.
4241 The DJGPP version now uses termios functions for console I/O, which
4242 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4245 DOS-style file names with drive letters are now fully supported by
4248 It is now possible to debug DJGPP programs that switch their working
4249 directory. It is also possible to rerun the debuggee any number of
4250 times without restarting GDB; thus, you can use the same setup,
4251 breakpoints, etc. for many debugging sessions.
4253 * New native configurations
4255 ARM GNU/Linux arm*-*-linux*
4256 PowerPC GNU/Linux powerpc-*-linux*
4260 Motorola MCore mcore-*-*
4261 x86 VxWorks i[3456]86-*-vxworks*
4262 PowerPC VxWorks powerpc-*-vxworks*
4263 TI TMS320C80 tic80-*-*
4265 * OBSOLETE configurations
4267 Altos 3068 m68*-altos-*
4268 Convex c1-*-*, c2-*-*
4270 ARM RISCix arm-*-* (as host)
4273 Configurations that have been declared obsolete will be commented out,
4274 but the code will be left in place. If there is no activity to revive
4275 these configurations before the next release of GDB, the sources will
4276 be permanently REMOVED.
4278 * Gould support removed
4280 Support for the Gould PowerNode and NP1 has been removed.
4282 * New features for SVR4
4284 On SVR4 native platforms (such as Solaris), if you attach to a process
4285 without first loading a symbol file, GDB will now attempt to locate and
4286 load symbols from the running process's executable file.
4288 * Many C++ enhancements
4290 C++ support has been greatly improved. Overload resolution now works properly
4291 in almost all cases. RTTI support is on the way.
4293 * Remote targets can connect to a sub-program
4295 A popen(3) style serial-device has been added. This device starts a
4296 sub-process (such as a stand-alone simulator) and then communicates
4297 with that. The sub-program to run is specified using the syntax
4298 ``|<program> <args>'' vis:
4300 (gdb) set remotedebug 1
4301 (gdb) target extended-remote |mn10300-elf-sim program-args
4303 * MIPS 64 remote protocol
4305 A long standing bug in the mips64 remote protocol where by GDB
4306 expected certain 32 bit registers (ex SR) to be transfered as 32
4307 instead of 64 bits has been fixed.
4309 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4310 added to provide backward compatibility with older versions of GDB.
4312 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4314 The command ``set remotebinarydownload'' command has been replaced by
4315 ``set remote X-packet''. Other commands in ``set remote'' family
4316 include ``set remote P-packet''.
4318 * Breakpoint commands accept ranges.
4320 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4321 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4322 ``tracepoint passcount'' also accepts a range of tracepoints.
4324 * ``apropos'' command added.
4326 The ``apropos'' command searches through command names and
4327 documentation strings, printing out matches, making it much easier to
4328 try to find a command that does what you are looking for.
4332 A new machine oriented interface (MI) has been added to GDB. This
4333 interface is designed for debug environments running GDB as a separate
4334 process. This is part of the long term libGDB project. See the
4335 "GDB/MI" chapter of the GDB manual for further information. It can be
4336 enabled by configuring with:
4338 .../configure --enable-gdbmi
4340 *** Changes in GDB-4.18:
4342 * New native configurations
4344 HP-UX 10.20 hppa*-*-hpux10.20
4345 HP-UX 11.x hppa*-*-hpux11.0*
4346 M68K GNU/Linux m68*-*-linux*
4350 Fujitsu FR30 fr30-*-elf*
4351 Intel StrongARM strongarm-*-*
4352 Mitsubishi D30V d30v-*-*
4354 * OBSOLETE configurations
4356 Gould PowerNode, NP1 np1-*-*, pn-*-*
4358 Configurations that have been declared obsolete will be commented out,
4359 but the code will be left in place. If there is no activity to revive
4360 these configurations before the next release of GDB, the sources will
4361 be permanently REMOVED.
4365 As a compatibility experiment, GDB's source files buildsym.h and
4366 buildsym.c have been converted to pure standard C, no longer
4367 containing any K&R compatibility code. We believe that all systems in
4368 use today either come with a standard C compiler, or have a GCC port
4369 available. If this is not true, please report the affected
4370 configuration to bug-gdb@gnu.org immediately. See the README file for
4371 information about getting a standard C compiler if you don't have one
4376 GDB now uses readline 2.2.
4378 * set extension-language
4380 You can now control the mapping between filename extensions and source
4381 languages by using the `set extension-language' command. For instance,
4382 you can ask GDB to treat .c files as C++ by saying
4383 set extension-language .c c++
4384 The command `info extensions' lists all of the recognized extensions
4385 and their associated languages.
4387 * Setting processor type for PowerPC and RS/6000
4389 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4390 you can use the `set processor' command to specify what variant of the
4391 PowerPC family you are debugging. The command
4395 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4396 following PowerPC and RS6000 variants:
4398 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4399 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4401 403GC IBM PowerPC 403GC
4402 505 Motorola PowerPC 505
4403 860 Motorola PowerPC 860 or 850
4404 601 Motorola PowerPC 601
4405 602 Motorola PowerPC 602
4406 603 Motorola/IBM PowerPC 603 or 603e
4407 604 Motorola PowerPC 604 or 604e
4408 750 Motorola/IBM PowerPC 750 or 750
4410 At the moment, this command just tells GDB what to name the
4411 special-purpose processor registers. Since almost all the affected
4412 registers are inaccessible to user-level programs, this command is
4413 only useful for remote debugging in its present form.
4417 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4418 more extensive support for HP-UX. Added features include shared
4419 library support, kernel threads and hardware watchpoints for 11.00,
4420 support for HP's ANSI C and C++ compilers, and a compatibility mode
4421 for xdb and dbx commands.
4425 HP's donation includes the new concept of catchpoints, which is a
4426 generalization of the old catch command. On HP-UX, it is now possible
4427 to catch exec, fork, and vfork, as well as library loading.
4429 This means that the existing catch command has changed; its first
4430 argument now specifies the type of catch to be set up. See the
4431 output of "help catch" for a list of catchpoint types.
4433 * Debugging across forks
4435 On HP-UX, you can choose which process to debug when a fork() happens
4440 HP has donated a curses-based terminal user interface (TUI). To get
4441 it, build with --enable-tui. Although this can be enabled for any
4442 configuration, at present it only works for native HP debugging.
4444 * GDB remote protocol additions
4446 A new protocol packet 'X' that writes binary data is now available.
4447 Default behavior is to try 'X', then drop back to 'M' if the stub
4448 fails to respond. The settable variable `remotebinarydownload'
4449 allows explicit control over the use of 'X'.
4451 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4452 full 64-bit address. The command
4454 set remoteaddresssize 32
4456 can be used to revert to the old behaviour. For existing remote stubs
4457 the change should not be noticed, as the additional address information
4460 In order to assist in debugging stubs, you may use the maintenance
4461 command `packet' to send any text string to the stub. For instance,
4463 maint packet heythere
4465 sends the packet "$heythere#<checksum>". Note that it is very easy to
4466 disrupt a debugging session by sending the wrong packet at the wrong
4469 The compare-sections command allows you to compare section data on the
4470 target to what is in the executable file without uploading or
4471 downloading, by comparing CRC checksums.
4473 * Tracing can collect general expressions
4475 You may now collect general expressions at tracepoints. This requires
4476 further additions to the target-side stub; see tracepoint.c and
4477 doc/agentexpr.texi for further details.
4479 * mask-address variable for Mips
4481 For Mips targets, you may control the zeroing of the upper 32 bits of
4482 a 64-bit address by entering `set mask-address on'. This is mainly
4483 of interest to users of embedded R4xxx and R5xxx processors.
4485 * Higher serial baud rates
4487 GDB's serial code now allows you to specify baud rates 57600, 115200,
4488 230400, and 460800 baud. (Note that your host system may not be able
4489 to achieve all of these rates.)
4493 The i960 configuration now includes an initial implementation of a
4494 builtin simulator, contributed by Jim Wilson.
4497 *** Changes in GDB-4.17:
4499 * New native configurations
4501 Alpha GNU/Linux alpha*-*-linux*
4502 Unixware 2.x i[3456]86-unixware2*
4503 Irix 6.x mips*-sgi-irix6*
4504 PowerPC GNU/Linux powerpc-*-linux*
4505 PowerPC Solaris powerpcle-*-solaris*
4506 Sparc GNU/Linux sparc-*-linux*
4507 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4511 Argonaut Risc Chip (ARC) arc-*-*
4512 Hitachi H8/300S h8300*-*-*
4513 Matsushita MN10200 w/simulator mn10200-*-*
4514 Matsushita MN10300 w/simulator mn10300-*-*
4515 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4516 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4517 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4518 Mitsubishi D10V w/simulator d10v-*-*
4519 Mitsubishi M32R/D w/simulator m32r-*-elf*
4520 Tsqware Sparclet sparclet-*-*
4521 NEC V850 w/simulator v850-*-*
4523 * New debugging protocols
4525 ARM with RDI protocol arm*-*-*
4526 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4527 DDB and LSI variants of PMON protocol mips*-*-*
4528 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4529 PowerPC with SDS protocol powerpc{,le}-*-eabi
4530 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4534 All configurations can now understand and use the DWARF 2 debugging
4535 format. The choice is automatic, if the symbol file contains DWARF 2
4540 GDB now includes basic Java language support. This support is
4541 only useful with Java compilers that produce native machine code.
4543 * solib-absolute-prefix and solib-search-path
4545 For SunOS and SVR4 shared libraries, you may now set the prefix for
4546 loading absolute shared library symbol files, and the search path for
4547 locating non-absolute shared library symbol files.
4549 * Live range splitting
4551 GDB can now effectively debug code for which GCC has performed live
4552 range splitting as part of its optimization. See gdb/doc/LRS for
4553 more details on the expected format of the stabs information.
4557 GDB's support for the GNU Hurd, including thread debugging, has been
4558 updated to work with current versions of the Hurd.
4562 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4563 instruction set. ARM GDB automatically detects when Thumb
4564 instructions are in use, and adjusts disassembly and backtracing
4569 GDB's MIPS target configurations now handle the MIP16 16-bit
4574 GDB now includes support for overlays; if an executable has been
4575 linked such that multiple sections are based at the same address, GDB
4576 will decide which section to use for symbolic info. You can choose to
4577 control the decision manually, using overlay commands, or implement
4578 additional target-side support and use "overlay load-target" to bring
4579 in the overlay mapping. Do "help overlay" for more detail.
4583 The command "info symbol <address>" displays information about
4584 the symbol at the specified address.
4588 The standard remote protocol now includes an extension that allows
4589 asynchronous collection and display of trace data. This requires
4590 extensive support in the target-side debugging stub. Tracing mode
4591 includes a new interaction mode in GDB and new commands: see the
4592 file tracepoint.c for more details.
4596 Configurations for embedded MIPS now include a simulator contributed
4597 by Cygnus Solutions. The simulator supports the instruction sets
4598 of most MIPS variants.
4602 Sparc configurations may now include the ERC32 simulator contributed
4603 by the European Space Agency. The simulator is not built into
4604 Sparc targets by default; configure with --enable-sim to include it.
4608 For target configurations that may include multiple variants of a
4609 basic architecture (such as MIPS and SH), you may now set the
4610 architecture explicitly. "set arch" sets, "info arch" lists
4611 the possible architectures.
4613 *** Changes in GDB-4.16:
4615 * New native configurations
4617 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4618 M68K NetBSD m68k-*-netbsd*
4619 PowerPC AIX 4.x powerpc-*-aix*
4620 PowerPC MacOS powerpc-*-macos*
4621 PowerPC Windows NT powerpcle-*-cygwin32
4622 RS/6000 AIX 4.x rs6000-*-aix4*
4626 ARM with RDP protocol arm-*-*
4627 I960 with MON960 i960-*-coff
4628 MIPS VxWorks mips*-*-vxworks*
4629 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4630 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4632 Matra Sparclet sparclet-*-*
4636 The powerpc-eabi configuration now includes the PSIM simulator,
4637 contributed by Andrew Cagney, with assistance from Mike Meissner.
4638 PSIM is a very elaborate model of the PowerPC, including not only
4639 basic instruction set execution, but also details of execution unit
4640 performance and I/O hardware. See sim/ppc/README for more details.
4644 GDB now works with Solaris 2.5.
4646 * Windows 95/NT native
4648 GDB will now work as a native debugger on Windows 95 and Windows NT.
4649 To build it from source, you must use the "gnu-win32" environment,
4650 which uses a DLL to emulate enough of Unix to run the GNU tools.
4651 Further information, binaries, and sources are available at
4652 ftp.cygnus.com, under pub/gnu-win32.
4654 * dont-repeat command
4656 If a user-defined command includes the command `dont-repeat', then the
4657 command will not be repeated if the user just types return. This is
4658 useful if the command is time-consuming to run, so that accidental
4659 extra keystrokes don't run the same command many times.
4661 * Send break instead of ^C
4663 The standard remote protocol now includes an option to send a break
4664 rather than a ^C to the target in order to interrupt it. By default,
4665 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4667 * Remote protocol timeout
4669 The standard remote protocol includes a new variable `remotetimeout'
4670 that allows you to set the number of seconds before GDB gives up trying
4671 to read from the target. The default value is 2.
4673 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4675 By default GDB will automatically keep track of objects as they are
4676 loaded and unloaded by the dynamic linker. By using the command `set
4677 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4678 when shared library events occur, thus allowing you to set breakpoints
4679 in shared libraries which are explicitly loaded by the inferior.
4681 Note this feature does not work on hpux8. On hpux9 you must link
4682 /usr/lib/end.o into your program. This feature should work
4683 automatically on hpux10.
4685 * Irix 5.x hardware watchpoint support
4687 Irix 5 configurations now support the use of hardware watchpoints.
4689 * Mips protocol "SYN garbage limit"
4691 When debugging a Mips target using the `target mips' protocol, you
4692 may set the number of characters that GDB will ignore by setting
4693 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4694 every character. The default value is 1050.
4696 * Recording and replaying remote debug sessions
4698 If you set `remotelogfile' to the name of a file, gdb will write to it
4699 a recording of a remote debug session. This recording may then be
4700 replayed back to gdb using "gdbreplay". See gdbserver/README for
4701 details. This is useful when you have a problem with GDB while doing
4702 remote debugging; you can make a recording of the session and send it
4703 to someone else, who can then recreate the problem.
4705 * Speedups for remote debugging
4707 GDB includes speedups for downloading and stepping MIPS systems using
4708 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4709 and more efficient S-record downloading.
4711 * Memory use reductions and statistics collection
4713 GDB now uses less memory and reports statistics about memory usage.
4714 Try the `maint print statistics' command, for example.
4716 *** Changes in GDB-4.15:
4718 * Psymtabs for XCOFF
4720 The symbol reader for AIX GDB now uses partial symbol tables. This
4721 can greatly improve startup time, especially for large executables.
4723 * Remote targets use caching
4725 Remote targets now use a data cache to speed up communication with the
4726 remote side. The data cache could lead to incorrect results because
4727 it doesn't know about volatile variables, thus making it impossible to
4728 debug targets which use memory mapped I/O devices. `set remotecache
4729 off' turns the the data cache off.
4731 * Remote targets may have threads
4733 The standard remote protocol now includes support for multiple threads
4734 in the target system, using new protocol commands 'H' and 'T'. See
4735 gdb/remote.c for details.
4739 If GDB is configured with `--enable-netrom', then it will include
4740 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4741 acts as though it is a bank of ROM on the target board, but you can
4742 write into it over the network. GDB's support consists only of
4743 support for fast loading into the emulated ROM; to debug, you must use
4744 another protocol, such as standard remote protocol. The usual
4745 sequence is something like
4747 target nrom <netrom-hostname>
4749 target remote <netrom-hostname>:1235
4753 GDB now includes support for the Apple Macintosh, as a host only. It
4754 may be run as either an MPW tool or as a standalone application, and
4755 it can debug through the serial port. All the usual GDB commands are
4756 available, but to the target command, you must supply "serial" as the
4757 device type instead of "/dev/ttyXX". See mpw-README in the main
4758 directory for more information on how to build. The MPW configuration
4759 scripts */mpw-config.in support only a few targets, and only the
4760 mips-idt-ecoff target has been tested.
4764 GDB configuration now uses autoconf. This is not user-visible,
4765 but does simplify configuration and building.
4769 GDB now supports hpux10.
4771 *** Changes in GDB-4.14:
4773 * New native configurations
4775 x86 FreeBSD i[345]86-*-freebsd
4776 x86 NetBSD i[345]86-*-netbsd
4777 NS32k NetBSD ns32k-*-netbsd
4778 Sparc NetBSD sparc-*-netbsd
4782 A29K VxWorks a29k-*-vxworks
4783 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4784 CPU32 EST-300 emulator m68*-*-est*
4785 PowerPC ELF powerpc-*-elf
4788 * Alpha OSF/1 support for procfs
4790 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4791 possible to attach to running processes. As the mounting of the /proc
4792 filesystem is optional on the Alpha, GDB automatically determines
4793 the availability of /proc during startup. This can lead to problems
4794 if /proc is unmounted after GDB has been started.
4796 * Arguments to user-defined commands
4798 User commands may accept up to 10 arguments separated by whitespace.
4799 Arguments are accessed within the user command via $arg0..$arg9. A
4802 print $arg0 + $arg1 + $arg2
4804 To execute the command use:
4807 Defines the command "adder" which prints the sum of its three arguments.
4808 Note the arguments are text substitutions, so they may reference variables,
4809 use complex expressions, or even perform inferior function calls.
4811 * New `if' and `while' commands
4813 This makes it possible to write more sophisticated user-defined
4814 commands. Both commands take a single argument, which is the
4815 expression to evaluate, and must be followed by the commands to
4816 execute, one per line, if the expression is nonzero, the list being
4817 terminated by the word `end'. The `if' command list may include an
4818 `else' word, which causes the following commands to be executed only
4819 if the expression is zero.
4821 * Fortran source language mode
4823 GDB now includes partial support for Fortran 77. It will recognize
4824 Fortran programs and can evaluate a subset of Fortran expressions, but
4825 variables and functions may not be handled correctly. GDB will work
4826 with G77, but does not yet know much about symbols emitted by other
4829 * Better HPUX support
4831 Most debugging facilities now work on dynamic executables for HPPAs
4832 running hpux9 or later. You can attach to running dynamically linked
4833 processes, but by default the dynamic libraries will be read-only, so
4834 for instance you won't be able to put breakpoints in them. To change
4835 that behavior do the following before running the program:
4841 This will cause the libraries to be mapped private and read-write.
4842 To revert to the normal behavior, do this:
4848 You cannot set breakpoints or examine data in the library until after
4849 the library is loaded if the function/data symbols do not have
4852 GDB can now also read debug symbols produced by the HP C compiler on
4853 HPPAs (sorry, no C++, Fortran or 68k support).
4855 * Target byte order now dynamically selectable
4857 You can choose which byte order to use with a target system, via the
4858 commands "set endian big" and "set endian little", and you can see the
4859 current setting by using "show endian". You can also give the command
4860 "set endian auto", in which case GDB will use the byte order
4861 associated with the executable. Currently, only embedded MIPS
4862 configurations support dynamic selection of target byte order.
4864 * New DOS host serial code
4866 This version uses DPMI interrupts to handle buffered I/O, so you
4867 no longer need to run asynctsr when debugging boards connected to
4870 *** Changes in GDB-4.13:
4872 * New "complete" command
4874 This lists all the possible completions for the rest of the line, if it
4875 were to be given as a command itself. This is intended for use by emacs.
4877 * Trailing space optional in prompt
4879 "set prompt" no longer adds a space for you after the prompt you set. This
4880 allows you to set a prompt which ends in a space or one that does not.
4882 * Breakpoint hit counts
4884 "info break" now displays a count of the number of times the breakpoint
4885 has been hit. This is especially useful in conjunction with "ignore"; you
4886 can ignore a large number of breakpoint hits, look at the breakpoint info
4887 to see how many times the breakpoint was hit, then run again, ignoring one
4888 less than that number, and this will get you quickly to the last hit of
4891 * Ability to stop printing at NULL character
4893 "set print null-stop" will cause GDB to stop printing the characters of
4894 an array when the first NULL is encountered. This is useful when large
4895 arrays actually contain only short strings.
4897 * Shared library breakpoints
4899 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4900 breakpoints in shared libraries before the executable is run.
4902 * Hardware watchpoints
4904 There is a new hardware breakpoint for the watch command for sparclite
4905 targets. See gdb/sparclite/hw_breakpoint.note.
4907 Hardware watchpoints are also now supported under GNU/Linux.
4911 Annotations have been added. These are for use with graphical interfaces,
4912 and are still experimental. Currently only gdba.el uses these.
4914 * Improved Irix 5 support
4916 GDB now works properly with Irix 5.2.
4918 * Improved HPPA support
4920 GDB now works properly with the latest GCC and GAS.
4922 * New native configurations
4924 Sequent PTX4 i[34]86-sequent-ptx4
4925 HPPA running OSF/1 hppa*-*-osf*
4926 Atari TT running SVR4 m68*-*-sysv4*
4927 RS/6000 LynxOS rs6000-*-lynxos*
4931 OS/9000 i[34]86-*-os9k
4932 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4935 * Hitachi SH7000 and E7000-PC ICE support
4937 There is now support for communicating with the Hitachi E7000-PC ICE.
4938 This is available automatically when GDB is configured for the SH.
4942 As usual, a variety of small fixes and improvements, both generic
4943 and configuration-specific. See the ChangeLog for more detail.
4945 *** Changes in GDB-4.12:
4947 * Irix 5 is now supported
4951 GDB-4.12 on the HPPA has a number of changes which make it unable
4952 to debug the output from the currently released versions of GCC and
4953 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4954 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4955 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4958 *** Changes in GDB-4.11:
4960 * User visible changes:
4964 The "set remotedebug" option is now consistent between the mips remote
4965 target, remote targets using the gdb-specific protocol, UDI (AMD's
4966 debug protocol for the 29k) and the 88k bug monitor. It is now an
4967 integer specifying a debug level (normally 0 or 1, but 2 means more
4968 debugging info for the mips target).
4970 * DEC Alpha native support
4972 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4973 debug info, but GDB works fairly well with the DEC compiler and should
4974 work with a future GCC release. See the README file for a few
4975 Alpha-specific notes.
4977 * Preliminary thread implementation
4979 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4981 * LynxOS native and target support for 386
4983 This release has been hosted on LynxOS 2.2, and also can be configured
4984 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4987 * Improvements in C++ mangling/demangling.
4989 This release has much better g++ debugging, specifically in name
4990 mangling/demangling, virtual function calls, print virtual table,
4991 call methods, ...etc.
4993 *** Changes in GDB-4.10:
4995 * User visible changes:
4997 Remote debugging using the GDB-specific (`target remote') protocol now
4998 supports the `load' command. This is only useful if you have some
4999 other way of getting the stub to the target system, and you can put it
5000 somewhere in memory where it won't get clobbered by the download.
5002 Filename completion now works.
5004 When run under emacs mode, the "info line" command now causes the
5005 arrow to point to the line specified. Also, "info line" prints
5006 addresses in symbolic form (as well as hex).
5008 All vxworks based targets now support a user settable option, called
5009 vxworks-timeout. This option represents the number of seconds gdb
5010 should wait for responses to rpc's. You might want to use this if
5011 your vxworks target is, perhaps, a slow software simulator or happens
5012 to be on the far side of a thin network line.
5016 This release contains support for using a DEC alpha as a GDB host for
5017 cross debugging. Native alpha debugging is not supported yet.
5020 *** Changes in GDB-4.9:
5024 This is the first GDB release which is accompanied by a matching testsuite.
5025 The testsuite requires installation of dejagnu, which should be available
5026 via ftp from most sites that carry GNU software.
5030 'Cfront' style demangling has had its name changed to 'ARM' style, to
5031 emphasize that it was written from the specifications in the C++ Annotated
5032 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5033 disclaimers, it still generated too much confusion with users attempting to
5034 use gdb with AT&T cfront.
5038 GDB now uses a standard remote interface to a simulator library.
5039 So far, the library contains simulators for the Zilog Z8001/2, the
5040 Hitachi H8/300, H8/500 and Super-H.
5042 * New targets supported
5044 H8/300 simulator h8300-hitachi-hms or h8300hms
5045 H8/500 simulator h8500-hitachi-hms or h8500hms
5046 SH simulator sh-hitachi-hms or sh
5047 Z8000 simulator z8k-zilog-none or z8ksim
5048 IDT MIPS board over serial line mips-idt-ecoff
5050 Cross-debugging to GO32 targets is supported. It requires a custom
5051 version of the i386-stub.c module which is integrated with the
5052 GO32 memory extender.
5054 * New remote protocols
5056 MIPS remote debugging protocol.
5058 * New source languages supported
5060 This version includes preliminary support for Chill, a Pascal like language
5061 used by telecommunications companies. Chill support is also being integrated
5062 into the GNU compiler, but we don't know when it will be publically available.
5065 *** Changes in GDB-4.8:
5067 * HP Precision Architecture supported
5069 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5070 version of this support was available as a set of patches from the
5071 University of Utah. GDB does not support debugging of programs
5072 compiled with the HP compiler, because HP will not document their file
5073 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5074 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5076 Many problems in the preliminary version have been fixed.
5078 * Faster and better demangling
5080 We have improved template demangling and fixed numerous bugs in the GNU style
5081 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5082 character types (wchar_t) are now supported. Demangling of each symbol is now
5083 only done once, and is cached when the symbol table for a file is read in.
5084 This results in a small increase in memory usage for C programs, a moderate
5085 increase in memory usage for C++ programs, and a fantastic speedup in
5088 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5089 from the specifications in the Annotated Reference Manual, which AT&T's
5090 compiler does not actually implement.
5092 * G++ multiple inheritance compiler problem
5094 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5095 inheritance lattices was reworked to properly discover ambiguities. We
5096 recently found an example which causes this new algorithm to fail in a
5097 very subtle way, producing bad debug information for those classes.
5098 The file 'gcc.patch' (in this directory) can be applied to gcc to
5099 circumvent the problem. A future GCC release will contain a complete
5102 The previous G++ debug info problem (mentioned below for the gdb-4.7
5103 release) is fixed in gcc version 2.3.2.
5105 * Improved configure script
5107 The `configure' script will now attempt to guess your system type if
5108 you don't supply a host system type. The old scheme of supplying a
5109 host system triplet is preferable over using this. All the magic is
5110 done in the new `config.guess' script. Examine it for details.
5112 We have also brought our configure script much more in line with the FSF's
5113 version. It now supports the --with-xxx options. In particular,
5114 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5115 The resulting GDB will not be able to read arbitrary object file formats --
5116 only the format ``expected'' to be used on the configured target system.
5117 We hope to make this the default in a future release.
5119 * Documentation improvements
5121 There's new internal documentation on how to modify GDB, and how to
5122 produce clean changes to the code. We implore people to read it
5123 before submitting changes.
5125 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5126 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5127 `info' files are also provided. To build `info' files from scratch,
5128 you will need the latest `makeinfo' release, which will be available in
5129 a future texinfo-X.Y release.
5131 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5132 We're not sure exactly which versions have this problem, but it has
5133 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5134 or better. If that isn't possible, there is a patch in
5135 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5136 around this problem.
5140 GDB now supports array constants that can be used in expressions typed in by
5141 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5142 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5145 The new directory `gdb/sparclite' contains a program that demonstrates
5146 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5148 * New native hosts supported
5150 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5151 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5153 * New targets supported
5155 AMD 29k family via UDI a29k-amd-udi or udi29k
5157 * New file formats supported
5159 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5160 HPUX core files, and SCO 3.2v2 core files.
5164 Attaching to processes now works again; thanks for the many bug reports.
5166 We have also stomped on a bunch of core dumps caused by
5167 printf_filtered("%s") problems.
5169 We eliminated a copyright problem on the rpc and ptrace header files
5170 for VxWorks, which was discovered at the last minute during the 4.7
5171 release. You should now be able to build a VxWorks GDB.
5173 You can now interrupt gdb while an attached process is running. This
5174 will cause the attached process to stop, and give control back to GDB.
5176 We fixed problems caused by using too many file descriptors
5177 for reading symbols from object files and libraries. This was
5178 especially a problem for programs that used many (~100) shared
5181 The `step' command now only enters a subroutine if there is line number
5182 information for the subroutine. Otherwise it acts like the `next'
5183 command. Previously, `step' would enter subroutines if there was
5184 any debugging information about the routine. This avoids problems
5185 when using `cc -g1' on MIPS machines.
5187 * Internal improvements
5189 GDB's internal interfaces have been improved to make it easier to support
5190 debugging of multiple languages in the future.
5192 GDB now uses a common structure for symbol information internally.
5193 Minimal symbols (derived from linkage symbols in object files), partial
5194 symbols (from a quick scan of debug information), and full symbols
5195 contain a common subset of information, making it easier to write
5196 shared code that handles any of them.
5198 * New command line options
5200 We now accept --silent as an alias for --quiet.
5204 The memory-mapped-malloc library is now licensed under the GNU Library
5205 General Public License.
5207 *** Changes in GDB-4.7:
5209 * Host/native/target split
5211 GDB has had some major internal surgery to untangle the support for
5212 hosts and remote targets. Now, when you configure GDB for a remote
5213 target, it will no longer load in all of the support for debugging
5214 local programs on the host. When fully completed and tested, this will
5215 ensure that arbitrary host/target combinations are possible.
5217 The primary conceptual shift is to separate the non-portable code in
5218 GDB into three categories. Host specific code is required any time GDB
5219 is compiled on that host, regardless of the target. Target specific
5220 code relates to the peculiarities of the target, but can be compiled on
5221 any host. Native specific code is everything else: it can only be
5222 built when the host and target are the same system. Child process
5223 handling and core file support are two common `native' examples.
5225 GDB's use of /proc for controlling Unix child processes is now cleaner.
5226 It has been split out into a single module under the `target_ops' vector,
5227 plus two native-dependent functions for each system that uses /proc.
5229 * New hosts supported
5231 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5232 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5233 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5235 * New targets supported
5237 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5238 68030 and CPU32 m68030-*-*, m68332-*-*
5240 * New native hosts supported
5242 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5243 (386bsd is not well tested yet)
5244 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5246 * New file formats supported
5248 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5249 supports reading of `a.out.adobe' object files, which are an a.out
5250 format extended with minimal information about multiple sections.
5254 `show copying' is the same as the old `info copying'.
5255 `show warranty' is the same as `info warrantee'.
5256 These were renamed for consistency. The old commands continue to work.
5258 `info handle' is a new alias for `info signals'.
5260 You can now define pre-command hooks, which attach arbitrary command
5261 scripts to any command. The commands in the hook will be executed
5262 prior to the user's command. You can also create a hook which will be
5263 executed whenever the program stops. See gdb.texinfo.
5267 We now deal with Cfront style name mangling, and can even extract type
5268 info from mangled symbols. GDB can automatically figure out which
5269 symbol mangling style your C++ compiler uses.
5271 Calling of methods and virtual functions has been improved as well.
5275 The crash that occured when debugging Sun Ansi-C compiled binaries is
5276 fixed. This was due to mishandling of the extra N_SO stabs output
5279 We also finally got Ultrix 4.2 running in house, and fixed core file
5280 support, with help from a dozen people on the net.
5282 John M. Farrell discovered that the reason that single-stepping was so
5283 slow on all of the Mips based platforms (primarily SGI and DEC) was
5284 that we were trying to demangle and lookup a symbol used for internal
5285 purposes on every instruction that was being stepped through. Changing
5286 the name of that symbol so that it couldn't be mistaken for a C++
5287 mangled symbol sped things up a great deal.
5289 Rich Pixley sped up symbol lookups in general by getting much smarter
5290 about when C++ symbol mangling is necessary. This should make symbol
5291 completion (TAB on the command line) much faster. It's not as fast as
5292 we'd like, but it's significantly faster than gdb-4.6.
5296 A new user controllable variable 'call_scratch_address' can
5297 specify the location of a scratch area to be used when GDB
5298 calls a function in the target. This is necessary because the
5299 usual method of putting the scratch area on the stack does not work
5300 in systems that have separate instruction and data spaces.
5302 We integrated changes to support the 29k UDI (Universal Debugger
5303 Interface), but discovered at the last minute that we didn't have all
5304 of the appropriate copyright paperwork. We are working with AMD to
5305 resolve this, and hope to have it available soon.
5309 We have sped up the remote serial line protocol, especially for targets
5310 with lots of registers. It now supports a new `expedited status' ('T')
5311 message which can be used in place of the existing 'S' status message.
5312 This allows the remote stub to send only the registers that GDB
5313 needs to make a quick decision about single-stepping or conditional
5314 breakpoints, eliminating the need to fetch the entire register set for
5315 each instruction being stepped through.
5317 The GDB remote serial protocol now implements a write-through cache for
5318 registers, only re-reading the registers if the target has run.
5320 There is also a new remote serial stub for SPARC processors. You can
5321 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5322 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5323 processor with a serial port.
5327 Configure.in files have become much easier to read and modify. A new
5328 `table driven' format makes it more obvious what configurations are
5329 supported, and what files each one uses.
5333 There is a new opcodes library which will eventually contain all of the
5334 disassembly routines and opcode tables. At present, it only contains
5335 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5336 disassembler (binutils/objdump) to share these routines.
5338 The libiberty library is now copylefted under the GNU Library General
5339 Public License. This allows more liberal use, and was done so libg++
5340 can use it. This makes no difference to GDB, since the Library License
5341 grants all the rights from the General Public License.
5345 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5346 reference to the stabs symbol info used by the debugger. It is (as far
5347 as we know) the only published document on this fascinating topic. We
5348 encourage you to read it, compare it to the stabs information on your
5349 system, and send improvements on the document in general (to
5350 bug-gdb@prep.ai.mit.edu).
5352 And, of course, many bugs have been fixed.
5355 *** Changes in GDB-4.6:
5357 * Better support for C++ function names
5359 GDB now accepts as input the "demangled form" of C++ overloaded function
5360 names and member function names, and can do command completion on such names
5361 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5362 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5363 Make use of command completion, it is your friend.
5365 GDB also now accepts a variety of C++ mangled symbol formats. They are
5366 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5367 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5368 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5369 for the list of formats.
5371 * G++ symbol mangling problem
5373 Recent versions of gcc have a bug in how they emit debugging information for
5374 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5375 directory) can be applied to gcc to fix the problem. Alternatively, if you
5376 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5377 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5378 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5381 * New 'maintenance' command
5383 All of the commands related to hacking GDB internals have been moved out of
5384 the main command set, and now live behind the 'maintenance' command. This
5385 can also be abbreviated as 'mt'. The following changes were made:
5387 dump-me -> maintenance dump-me
5388 info all-breakpoints -> maintenance info breakpoints
5389 printmsyms -> maintenance print msyms
5390 printobjfiles -> maintenance print objfiles
5391 printpsyms -> maintenance print psymbols
5392 printsyms -> maintenance print symbols
5394 The following commands are new:
5396 maintenance demangle Call internal GDB demangler routine to
5397 demangle a C++ link name and prints the result.
5398 maintenance print type Print a type chain for a given symbol
5400 * Change to .gdbinit file processing
5402 We now read the $HOME/.gdbinit file before processing the argv arguments
5403 (e.g. reading symbol files or core files). This allows global parameters to
5404 be set, which will apply during the symbol reading. The ./.gdbinit is still
5405 read after argv processing.
5407 * New hosts supported
5409 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5411 GNU/Linux support i386-unknown-linux or linux
5413 We are also including code to support the HP/PA running BSD and HPUX. This
5414 is almost guaranteed not to work, as we didn't have time to test or build it
5415 for this release. We are including it so that the more adventurous (or
5416 masochistic) of you can play with it. We also had major problems with the
5417 fact that the compiler that we got from HP doesn't support the -g option.
5420 * New targets supported
5422 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5424 * More smarts about finding #include files
5426 GDB now remembers the compilation directory for all include files, and for
5427 all files from which C is generated (like yacc and lex sources). This
5428 greatly improves GDB's ability to find yacc/lex sources, and include files,
5429 especially if you are debugging your program from a directory different from
5430 the one that contains your sources.
5432 We also fixed a bug which caused difficulty with listing and setting
5433 breakpoints in include files which contain C code. (In the past, you had to
5434 try twice in order to list an include file that you hadn't looked at before.)
5436 * Interesting infernals change
5438 GDB now deals with arbitrary numbers of sections, where the symbols for each
5439 section must be relocated relative to that section's landing place in the
5440 target's address space. This work was needed to support ELF with embedded
5441 stabs used by Solaris-2.0.
5443 * Bug fixes (of course!)
5445 There have been loads of fixes for the following things:
5446 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5447 i960, stabs, DOS(GO32), procfs, etc...
5449 See the ChangeLog for details.
5451 *** Changes in GDB-4.5:
5453 * New machines supported (host and target)
5455 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5457 SGI Irix-4.x mips-sgi-irix4 or iris4
5459 * New malloc package
5461 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5462 Mmalloc is capable of handling mutiple heaps of memory. It is also
5463 capable of saving a heap to a file, and then mapping it back in later.
5464 This can be used to greatly speedup the startup of GDB by using a
5465 pre-parsed symbol table which lives in a mmalloc managed heap. For
5466 more details, please read mmalloc/mmalloc.texi.
5470 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5471 'help info proc' for details.
5473 * MIPS ecoff symbol table format
5475 The code that reads MIPS symbol table format is now supported on all hosts.
5476 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5479 * File name changes for MS-DOS
5481 Many files in the config directories have been renamed to make it easier to
5482 support GDB on MS-DOSe systems (which have very restrictive file name
5483 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5484 environment) is close to working but has some remaining problems. Note
5485 that debugging of DOS programs is not supported, due to limitations
5486 in the ``operating system'', but it can be used to host cross-debugging.
5488 * Cross byte order fixes
5490 Many fixes have been made to support cross debugging of Sparc and MIPS
5491 targets from hosts whose byte order differs.
5493 * New -mapped and -readnow options
5495 If memory-mapped files are available on your system through the 'mmap'
5496 system call, you can use the -mapped option on the `file' or
5497 `symbol-file' commands to cause GDB to write the symbols from your
5498 program into a reusable file. If the program you are debugging is
5499 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5500 Future GDB debugging sessions will notice the presence of this file,
5501 and will quickly map in symbol information from it, rather than reading
5502 the symbol table from the executable program. Using the '-mapped'
5503 option in a GDB `file' or `symbol-file' command has the same effect as
5504 starting GDB with the '-mapped' command-line option.
5506 You can cause GDB to read the entire symbol table immediately by using
5507 the '-readnow' option with any of the commands that load symbol table
5508 information (or on the GDB command line). This makes the command
5509 slower, but makes future operations faster.
5511 The -mapped and -readnow options are typically combined in order to
5512 build a `fred.syms' file that contains complete symbol information.
5513 A simple GDB invocation to do nothing but build a `.syms' file for future
5516 gdb -batch -nx -mapped -readnow programname
5518 The `.syms' file is specific to the host machine on which GDB is run.
5519 It holds an exact image of GDB's internal symbol table. It cannot be
5520 shared across multiple host platforms.
5522 * longjmp() handling
5524 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5525 siglongjmp() without losing control. This feature has not yet been ported to
5526 all systems. It currently works on many 386 platforms, all MIPS-based
5527 platforms (SGI, DECstation, etc), and Sun3/4.
5531 Preliminary work has been put in to support the new Solaris OS from Sun. At
5532 this time, it can control and debug processes, but it is not capable of
5537 As always, many many bug fixes. The major areas were with g++, and mipsread.
5538 People using the MIPS-based platforms should experience fewer mysterious
5539 crashes and trashed symbol tables.
5541 *** Changes in GDB-4.4:
5543 * New machines supported (host and target)
5545 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5547 BSD Reno on Vax vax-dec-bsd
5548 Ultrix on Vax vax-dec-ultrix
5550 * New machines supported (target)
5552 AMD 29000 embedded, using EBMON a29k-none-none
5556 GDB continues to improve its handling of C++. `References' work better.
5557 The demangler has also been improved, and now deals with symbols mangled as
5558 per the Annotated C++ Reference Guide.
5560 GDB also now handles `stabs' symbol information embedded in MIPS
5561 `ecoff' symbol tables. Since the ecoff format was not easily
5562 extensible to handle new languages such as C++, this appeared to be a
5563 good way to put C++ debugging info into MIPS binaries. This option
5564 will be supported in the GNU C compiler, version 2, when it is
5567 * New features for SVR4
5569 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5570 shared libraries. Debugging dynamically linked programs should present
5571 only minor differences from debugging statically linked programs.
5573 The `info proc' command will print out information about any process
5574 on an SVR4 system (including the one you are debugging). At the moment,
5575 it prints the address mappings of the process.
5577 If you bring up GDB on another SVR4 system, please send mail to
5578 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5580 * Better dynamic linking support in SunOS
5582 Reading symbols from shared libraries which contain debugging symbols
5583 now works properly. However, there remain issues such as automatic
5584 skipping of `transfer vector' code during function calls, which
5585 make it harder to debug code in a shared library, than to debug the
5586 same code linked statically.
5590 GDB is now using the latest `getopt' routines from the FSF. This
5591 version accepts the -- prefix for options with long names. GDB will
5592 continue to accept the old forms (-option and +option) as well.
5593 Various single letter abbreviations for options have been explicity
5594 added to the option table so that they won't get overshadowed in the
5595 future by other options that begin with the same letter.
5599 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5600 Many assorted bugs have been handled. Many more remain to be handled.
5601 See the various ChangeLog files (primarily in gdb and bfd) for details.
5604 *** Changes in GDB-4.3:
5606 * New machines supported (host and target)
5608 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5609 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5610 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5612 * Almost SCO Unix support
5614 We had hoped to support:
5615 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5616 (except for core file support), but we discovered very late in the release
5617 that it has problems with process groups that render gdb unusable. Sorry
5618 about that. I encourage people to fix it and post the fixes.
5620 * Preliminary ELF and DWARF support
5622 GDB can read ELF object files on System V Release 4, and can handle
5623 debugging records for C, in DWARF format, in ELF files. This support
5624 is preliminary. If you bring up GDB on another SVR4 system, please
5625 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5630 GDB now uses the latest `readline' library. One user-visible change
5631 is that two tabs will list possible command completions, which previously
5632 required typing M-? (meta-question mark, or ESC ?).
5636 The `stepi' bug that many of you noticed has been squashed.
5637 Many bugs in C++ have been handled. Many more remain to be handled.
5638 See the various ChangeLog files (primarily in gdb and bfd) for details.
5640 * State of the MIPS world (in case you wondered):
5642 GDB can understand the symbol tables emitted by the compilers
5643 supplied by most vendors of MIPS-based machines, including DEC. These
5644 symbol tables are in a format that essentially nobody else uses.
5646 Some versions of gcc come with an assembler post-processor called
5647 mips-tfile. This program is required if you want to do source-level
5648 debugging of gcc-compiled programs. I believe FSF does not ship
5649 mips-tfile with gcc version 1, but it will eventually come with gcc
5652 Debugging of g++ output remains a problem. g++ version 1.xx does not
5653 really support it at all. (If you're lucky, you should be able to get
5654 line numbers and stack traces to work, but no parameters or local
5655 variables.) With some work it should be possible to improve the
5658 When gcc version 2 is released, you will have somewhat better luck.
5659 However, even then you will get confusing results for inheritance and
5662 We will eventually provide full debugging of g++ output on
5663 DECstations. This will probably involve some kind of stabs-in-ecoff
5664 encapulation, but the details have not been worked out yet.
5667 *** Changes in GDB-4.2:
5669 * Improved configuration
5671 Only one copy of `configure' exists now, and it is not self-modifying.
5672 Porting BFD is simpler.
5676 The `step' and `next' commands now only stop at the first instruction
5677 of a source line. This prevents the multiple stops that used to occur
5678 in switch statements, for-loops, etc. `Step' continues to stop if a
5679 function that has debugging information is called within the line.
5683 Lots of small bugs fixed. More remain.
5685 * New host supported (not target)
5687 Intel 386 PC clone running Mach i386-none-mach
5690 *** Changes in GDB-4.1:
5692 * Multiple source language support
5694 GDB now has internal scaffolding to handle several source languages.
5695 It determines the type of each source file from its filename extension,
5696 and will switch expression parsing and number formatting to match the
5697 language of the function in the currently selected stack frame.
5698 You can also specifically set the language to be used, with
5699 `set language c' or `set language modula-2'.
5703 GDB now has preliminary support for the GNU Modula-2 compiler,
5704 currently under development at the State University of New York at
5705 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5706 continue through the fall of 1991 and into 1992.
5708 Other Modula-2 compilers are currently not supported, and attempting to
5709 debug programs compiled with them will likely result in an error as the
5710 symbol table is read. Feel free to work on it, though!
5712 There are hooks in GDB for strict type checking and range checking,
5713 in the `Modula-2 philosophy', but they do not currently work.
5717 GDB can now write to executable and core files (e.g. patch
5718 a variable's value). You must turn this switch on, specify
5719 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5720 by assigning a new value to a variable. Modifications take
5723 * Automatic SunOS shared library reading
5725 When you run your program, GDB automatically determines where its
5726 shared libraries (if any) have been loaded, and reads their symbols.
5727 The `share' command is no longer needed. This also works when
5728 examining core files.
5732 You can specify the number of lines that the `list' command shows.
5735 * New machines supported (host and target)
5737 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5738 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5739 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5741 * New hosts supported (not targets)
5743 IBM RT/PC: romp-ibm-aix or rtpc
5745 * New targets supported (not hosts)
5747 AMD 29000 embedded with COFF a29k-none-coff
5748 AMD 29000 embedded with a.out a29k-none-aout
5749 Ultracomputer remote kernel debug a29k-nyu-kern
5751 * New remote interfaces
5757 *** Changes in GDB-4.0:
5761 Wide output is wrapped at good places to make the output more readable.
5763 Gdb now supports cross-debugging from a host machine of one type to a
5764 target machine of another type. Communication with the target system
5765 is over serial lines. The ``target'' command handles connecting to the
5766 remote system; the ``load'' command will download a program into the
5767 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5768 also supports debugging of realtime processes running under VxWorks,
5769 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5770 stub on the target system.
5772 New CPUs supported include the AMD 29000 and Intel 960.
5774 GDB now reads object files and symbol tables via a ``binary file''
5775 library, which allows a single copy of GDB to debug programs of multiple
5776 object file types such as a.out and coff.
5778 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5779 refcard.dvi and refcard.ps are available to format it).
5782 * Control-Variable user interface simplified
5784 All variables that control the operation of the debugger can be set
5785 by the ``set'' command, and displayed by the ``show'' command.
5787 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5788 ``Show prompt'' produces the response:
5789 Gdb's prompt is new-gdb=>.
5791 What follows are the NEW set commands. The command ``help set'' will
5792 print a complete list of old and new set commands. ``help set FOO''
5793 will give a longer description of the variable FOO. ``show'' will show
5794 all of the variable descriptions and their current settings.
5796 confirm on/off: Enables warning questions for operations that are
5797 hard to recover from, e.g. rerunning the program while
5798 it is already running. Default is ON.
5800 editing on/off: Enables EMACS style command line editing
5801 of input. Previous lines can be recalled with
5802 control-P, the current line can be edited with control-B,
5803 you can search for commands with control-R, etc.
5806 history filename NAME: NAME is where the gdb command history
5807 will be stored. The default is .gdb_history,
5808 or the value of the environment variable
5811 history size N: The size, in commands, of the command history. The
5812 default is 256, or the value of the environment variable
5815 history save on/off: If this value is set to ON, the history file will
5816 be saved after exiting gdb. If set to OFF, the
5817 file will not be saved. The default is OFF.
5819 history expansion on/off: If this value is set to ON, then csh-like
5820 history expansion will be performed on
5821 command line input. The default is OFF.
5823 radix N: Sets the default radix for input and output. It can be set
5824 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5825 in the current radix, so "set radix 10" is always a no-op.
5827 height N: This integer value is the number of lines on a page. Default
5828 is 24, the current `stty rows'' setting, or the ``li#''
5829 setting from the termcap entry matching the environment
5832 width N: This integer value is the number of characters on a line.
5833 Default is 80, the current `stty cols'' setting, or the ``co#''
5834 setting from the termcap entry matching the environment
5837 Note: ``set screensize'' is obsolete. Use ``set height'' and
5838 ``set width'' instead.
5840 print address on/off: Print memory addresses in various command displays,
5841 such as stack traces and structure values. Gdb looks
5842 more ``symbolic'' if you turn this off; it looks more
5843 ``machine level'' with it on. Default is ON.
5845 print array on/off: Prettyprint arrays. New convenient format! Default
5848 print demangle on/off: Print C++ symbols in "source" form if on,
5851 print asm-demangle on/off: Same, for assembler level printouts
5854 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5857 * Support for Epoch Environment.
5859 The epoch environment is a version of Emacs v18 with windowing. One
5860 new command, ``inspect'', is identical to ``print'', except that if you
5861 are running in the epoch environment, the value is printed in its own
5865 * Support for Shared Libraries
5867 GDB can now debug programs and core files that use SunOS shared libraries.
5868 Symbols from a shared library cannot be referenced
5869 before the shared library has been linked with the program (this
5870 happens after you type ``run'' and before the function main() is entered).
5871 At any time after this linking (including when examining core files
5872 from dynamically linked programs), gdb reads the symbols from each
5873 shared library when you type the ``sharedlibrary'' command.
5874 It can be abbreviated ``share''.
5876 sharedlibrary REGEXP: Load shared object library symbols for files
5877 matching a unix regular expression. No argument
5878 indicates to load symbols for all shared libraries.
5880 info sharedlibrary: Status of loaded shared libraries.
5885 A watchpoint stops execution of a program whenever the value of an
5886 expression changes. Checking for this slows down execution
5887 tremendously whenever you are in the scope of the expression, but is
5888 quite useful for catching tough ``bit-spreader'' or pointer misuse
5889 problems. Some machines such as the 386 have hardware for doing this
5890 more quickly, and future versions of gdb will use this hardware.
5892 watch EXP: Set a watchpoint (breakpoint) for an expression.
5894 info watchpoints: Information about your watchpoints.
5896 delete N: Deletes watchpoint number N (same as breakpoints).
5897 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5898 enable N: Re-enables watchpoint number N (same as breakpoints).
5901 * C++ multiple inheritance
5903 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5906 * C++ exception handling
5908 Gdb now supports limited C++ exception handling. Besides the existing
5909 ability to breakpoint on an exception handler, gdb can breakpoint on
5910 the raising of an exception (before the stack is peeled back to the
5913 catch FOO: If there is a FOO exception handler in the dynamic scope,
5914 set a breakpoint to catch exceptions which may be raised there.
5915 Multiple exceptions (``catch foo bar baz'') may be caught.
5917 info catch: Lists all exceptions which may be caught in the
5918 current stack frame.
5921 * Minor command changes
5923 The command ``call func (arg, arg, ...)'' now acts like the print
5924 command, except it does not print or save a value if the function's result
5925 is void. This is similar to dbx usage.
5927 The ``up'' and ``down'' commands now always print the frame they end up
5928 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5929 frames without printing.
5931 * New directory command
5933 'dir' now adds directories to the FRONT of the source search path.
5934 The path starts off empty. Source files that contain debug information
5935 about the directory in which they were compiled can be found even
5936 with an empty path; Sun CC and GCC include this information. If GDB can't
5937 find your source file in the current directory, type "dir .".
5939 * Configuring GDB for compilation
5941 For normal use, type ``./configure host''. See README or gdb.texinfo
5944 GDB now handles cross debugging. If you are remotely debugging between
5945 two different machines, type ``./configure host -target=targ''.
5946 Host is the machine where GDB will run; targ is the machine
5947 where the program that you are debugging will run.