1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.9
7 * GDB now honors the content of the file /proc/PID/coredump_filter
8 (PID is the process ID) on GNU/Linux systems. This file can be used
9 to specify the types of memory mappings that will be included in a
10 corefile. For more information, please refer to the manual page of
11 "core(5)". GDB also has a new command: "set use-coredump-filter
12 on|off". It allows to set whether GDB will read the content of the
13 /proc/PID/coredump_filter file when generating a corefile.
15 * The "info os" command on GNU/Linux can now display information on
17 "info os cpus" Listing of all cpus/cores on the system
19 * GDB has two new commands: "set serial parity odd|even|none" and
20 "show serial parity". These allows to set or show parity for the
23 * The "info source" command now displays the producer string if it was
24 present in the debug info. This typically includes the compiler version
25 and may include things like its command line arguments.
27 * Directory names supplied to the "set sysroot" commands may be
28 prefixed with "target:" to tell GDB to access shared libraries from
29 the target system, be it local or remote. This replaces the prefix
30 "remote:". The default sysroot has been changed from "" to
31 "target:". "remote:" is automatically converted to "target:" for
32 backward compatibility.
34 * The system root specified by "set sysroot" will be prepended to the
35 filename of the main executable (if reported to GDB as absolute by
36 the operating system) when starting processes remotely, and when
37 attaching to already-running local or remote processes.
41 ** gdb.Objfile objects have a new attribute "username",
42 which is the name of the objfile as specified by the user,
43 without, for example, resolving symlinks.
44 ** You can now write frame unwinders in Python.
48 maint print symbol-cache
49 Print the contents of the symbol cache.
51 maint print symbol-cache-statistics
52 Print statistics of symbol cache usage.
54 maint flush-symbol-cache
55 Flush the contents of the symbol cache.
59 Start branch trace recording using Branch Trace Store (BTS) format.
65 Set the maximum number of candidates to be considered during
66 completion. The default value is 200. This limit allows GDB
67 to avoid generating large completion lists, the computation of
68 which can cause the debugger to become temporarily unresponsive.
70 maint set symbol-cache-size
71 maint show symbol-cache-size
72 Control the size of the symbol cache.
74 set|show record btrace bts buffer-size
75 Set and show the size of the ring buffer used for branch tracing in
77 The obtained size may differ from the requested size. Use "info
78 record" to see the obtained buffer size.
80 * The command 'thread apply all' can now support new option '-ascending'
81 to call its specified command for all threads in ascending order.
83 * Python/Guile scripting
85 ** GDB now supports auto-loading of Python/Guile scripts contained in the
86 special section named `.debug_gdb_scripts'.
90 qXfer:btrace-conf:read
91 Return the branch trace configuration for the current thread.
94 Set the requested ring buffer size for branch tracing in BTS format.
97 Indicates a memory breakpoint instruction was executed, irrespective
98 of whether it was GDB that planted the breakpoint or the breakpoint
99 is hardcoded in the program. This is required for correct non-stop
103 Indicates the target stopped for a hardware breakpoint. This is
104 required for correct non-stop mode operation.
107 Return information about files on the remote system.
110 Return the full absolute name of the file that was executed to
111 create a process running on the remote system.
113 * The info record command now shows the recording format and the
114 branch tracing configuration for the current thread when using
115 the btrace record target.
116 For the BTS format, it shows the ring buffer size.
118 * GDB now has support for DTrace USDT (Userland Static Defined
119 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
121 * GDB now supports access to vector registers on S/390 GNU/Linux
124 * Removed command line options
126 -xdb HP-UX XDB compatibility mode.
128 * Removed targets and native configurations
130 HP/PA running HP-UX hppa*-*-hpux*
131 Itanium running HP-UX ia64-*-hpux*
133 *** Changes in GDB 7.9
135 * GDB now supports hardware watchpoints on x86 GNU Hurd.
139 ** You can now access frame registers from Python scripts.
140 ** New attribute 'producer' for gdb.Symtab objects.
141 ** gdb.Objfile objects have a new attribute "progspace",
142 which is the gdb.Progspace object of the containing program space.
143 ** gdb.Objfile objects have a new attribute "owner".
144 ** gdb.Objfile objects have a new attribute "build_id",
145 which is the build ID generated when the file was built.
146 ** gdb.Objfile objects have a new method "add_separate_debug_file".
147 ** A new event "gdb.clear_objfiles" has been added, triggered when
148 selecting a new file to debug.
149 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
150 ** New function gdb.lookup_objfile.
152 New events which are triggered when GDB modifies the state of the
155 ** gdb.events.inferior_call_pre: Function call is about to be made.
156 ** gdb.events.inferior_call_post: Function call has just been made.
157 ** gdb.events.memory_changed: A memory location has been altered.
158 ** gdb.events.register_changed: A register has been altered.
160 * New Python-based convenience functions:
162 ** $_caller_is(name [, number_of_frames])
163 ** $_caller_matches(regexp [, number_of_frames])
164 ** $_any_caller_is(name [, number_of_frames])
165 ** $_any_caller_matches(regexp [, number_of_frames])
167 * GDB now supports the compilation and injection of source code into
168 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
169 to compile the source code to object code, and if successful, inject
170 and execute that code within the current context of the inferior.
171 Currently the C language is supported. The commands used to
172 interface with this new feature are:
174 compile code [-raw|-r] [--] [source code]
175 compile file [-raw|-r] filename
179 demangle [-l language] [--] name
180 Demangle "name" in the specified language, or the current language
181 if elided. This command is renamed from the "maint demangle" command.
182 The latter is kept as a no-op to avoid "maint demangle" being interpreted
183 as "maint demangler-warning".
185 queue-signal signal-name-or-number
186 Queue a signal to be delivered to the thread when it is resumed.
188 add-auto-load-scripts-directory directory
189 Add entries to the list of directories from which to load auto-loaded
192 maint print user-registers
193 List all currently available "user" registers.
195 compile code [-r|-raw] [--] [source code]
196 Compile, inject, and execute in the inferior the executable object
197 code produced by compiling the provided source code.
199 compile file [-r|-raw] filename
200 Compile and inject into the inferior the executable object code
201 produced by compiling the source code stored in the filename
204 * On resume, GDB now always passes the signal the program had stopped
205 for to the thread the signal was sent to, even if the user changed
206 threads before resuming. Previously GDB would often (but not
207 always) deliver the signal to the thread that happens to be current
210 * Conversely, the "signal" command now consistently delivers the
211 requested signal to the current thread. GDB now asks for
212 confirmation if the program had stopped for a signal and the user
213 switched threads meanwhile.
215 * "breakpoint always-inserted" modes "off" and "auto" merged.
217 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
218 won't remove breakpoints from the target until all threads stop,
219 even in non-stop mode. The "auto" mode has been removed, and "off"
220 is now the default mode.
224 set debug symbol-lookup
225 show debug symbol-lookup
226 Control display of debugging info regarding symbol lookup.
230 ** The -list-thread-groups command outputs an exit-code field for
231 inferiors that have exited.
235 MIPS SDE mips*-sde*-elf*
239 Support for these obsolete configurations has been removed.
241 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
242 SGI Irix-5.x mips-*-irix5*
243 SGI Irix-6.x mips-*-irix6*
244 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
245 VAX running Ultrix vax-*-ultrix*
247 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
248 and "assf"), have been removed. Use the "sharedlibrary" command, or
249 its alias "share", instead.
251 *** Changes in GDB 7.8
253 * New command line options
256 This is an alias for the --data-directory option.
258 * GDB supports printing and modifying of variable length automatic arrays
259 as specified in ISO C99.
261 * The ARM simulator now supports instruction level tracing
262 with or without disassembly.
266 GDB now has support for scripting using Guile. Whether this is
267 available is determined at configure time.
268 Guile version 2.0 or greater is required.
269 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
271 * New commands (for set/show, see "New options" below)
275 Invoke CODE by passing it to the Guile interpreter.
279 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
281 info auto-load guile-scripts [regexp]
282 Print the list of automatically loaded Guile scripts.
284 * The source command is now capable of sourcing Guile scripts.
285 This feature is dependent on the debugger being built with Guile support.
289 set print symbol-loading (off|brief|full)
290 show print symbol-loading
291 Control whether to print informational messages when loading symbol
292 information for a file. The default is "full", but when debugging
293 programs with large numbers of shared libraries the amount of output
296 set guile print-stack (none|message|full)
297 show guile print-stack
298 Show a stack trace when an error is encountered in a Guile script.
300 set auto-load guile-scripts (on|off)
301 show auto-load guile-scripts
302 Control auto-loading of Guile script files.
304 maint ada set ignore-descriptive-types (on|off)
305 maint ada show ignore-descriptive-types
306 Control whether the debugger should ignore descriptive types in Ada
307 programs. The default is not to ignore the descriptive types. See
308 the user manual for more details on descriptive types and the intended
309 usage of this option.
311 set auto-connect-native-target
313 Control whether GDB is allowed to automatically connect to the
314 native target for the run, attach, etc. commands when not connected
315 to any target yet. See also "target native" below.
317 set record btrace replay-memory-access (read-only|read-write)
318 show record btrace replay-memory-access
319 Control what memory accesses are allowed during replay.
321 maint set target-async (on|off)
322 maint show target-async
323 This controls whether GDB targets operate in synchronous or
324 asynchronous mode. Normally the default is asynchronous, if it is
325 available; but this can be changed to more easily debug problems
326 occurring only in synchronous mode.
328 set mi-async (on|off)
330 Control whether MI asynchronous mode is preferred. This supersedes
331 "set target-async" of previous GDB versions.
333 * "set target-async" is deprecated as a CLI option and is now an alias
334 for "set mi-async" (only puts MI into async mode).
336 * Background execution commands (e.g., "c&", "s&", etc.) are now
337 possible ``out of the box'' if the target supports them. Previously
338 the user would need to explicitly enable the possibility with the
339 "set target-async on" command.
341 * New features in the GDB remote stub, GDBserver
343 ** New option --debug-format=option1[,option2,...] allows one to add
344 additional text to each output. At present only timestamps
345 are supported: --debug-format=timestamps.
346 Timestamps can also be turned on with the
347 "monitor set debug-format timestamps" command from GDB.
349 * The 'record instruction-history' command now starts counting instructions
350 at one. This also affects the instruction ranges reported by the
351 'record function-call-history' command when given the /i modifier.
353 * The command 'record function-call-history' supports a new modifier '/c' to
354 indent the function names based on their call stack depth.
355 The fields for the '/i' and '/l' modifier have been reordered.
356 The source line range is now prefixed with 'at'.
357 The instruction range is now prefixed with 'inst'.
358 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
359 "record instruction-history" and "list" commands.
361 * The ranges given as arguments to the 'record function-call-history' and
362 'record instruction-history' commands are now inclusive.
364 * The btrace record target now supports the 'record goto' command.
365 For locations inside the execution trace, the back trace is computed
366 based on the information stored in the execution trace.
368 * The btrace record target supports limited reverse execution and replay.
369 The target does not record data and therefore does not allow reading
372 * The "catch syscall" command now works on s390*-linux* targets.
374 * The "compare-sections" command is no longer specific to target
375 remote. It now works with all targets.
377 * All native targets are now consistently called "native".
378 Consequently, the "target child", "target GNU", "target djgpp",
379 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
380 commands have been replaced with "target native". The QNX/NTO port
381 leaves the "procfs" target in place and adds a "native" target for
382 consistency with other ports. The impact on users should be minimal
383 as these commands previously either throwed an error, or were
384 no-ops. The target's name is visible in the output of the following
385 commands: "help target", "info target", "info files", "maint print
388 * The "target native" command now connects to the native target. This
389 can be used to launch native programs even when "set
390 auto-connect-native-target" is set to off.
392 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
394 * Support for Intel(R) AVX-512 registers on GNU/Linux.
395 Support displaying and modifying Intel(R) AVX-512 registers
396 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
400 qXfer:btrace:read's annex
401 The qXfer:btrace:read packet supports a new annex 'delta' to read
402 branch trace incrementally.
406 ** Valid Python operations on gdb.Value objects representing
407 structs/classes invoke the corresponding overloaded operators if
409 ** New `Xmethods' feature in the Python API. Xmethods are
410 additional methods or replacements for existing methods of a C++
411 class. This feature is useful for those cases where a method
412 defined in C++ source code could be inlined or optimized out by
413 the compiler, making it unavailable to GDB.
416 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
418 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
419 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
420 its alias "share", instead.
422 * The commands "set remotebaud" and "show remotebaud" are no longer
423 supported. Use "set serial baud" and "show serial baud" (respectively)
428 ** A new option "-gdb-set mi-async" replaces "-gdb-set
429 target-async". The latter is left as a deprecated alias of the
430 former for backward compatibility. If the target supports it,
431 CLI background execution commands are now always possible by
432 default, independently of whether the frontend stated a
433 preference for asynchronous execution with "-gdb-set mi-async".
434 Previously "-gdb-set target-async off" affected both MI execution
435 commands and CLI execution commands.
437 *** Changes in GDB 7.7
439 * Improved support for process record-replay and reverse debugging on
440 arm*-linux* targets. Support for thumb32 and syscall instruction
441 recording has been added.
443 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
445 * GDB now supports Fission DWP file format version 2.
446 http://gcc.gnu.org/wiki/DebugFission
448 * New convenience function "$_isvoid", to check whether an expression
449 is void. A void expression is an expression where the type of the
450 result is "void". For example, some convenience variables may be
451 "void" when evaluated (e.g., "$_exitcode" before the execution of
452 the program being debugged; or an undefined convenience variable).
453 Another example, when calling a function whose return type is
456 * The "maintenance print objfiles" command now takes an optional regexp.
458 * The "catch syscall" command now works on arm*-linux* targets.
460 * GDB now consistently shows "<not saved>" when printing values of
461 registers the debug info indicates have not been saved in the frame
462 and there's nowhere to retrieve them from
463 (callee-saved/call-clobbered registers):
468 (gdb) info registers rax
471 Before, the former would print "<optimized out>", and the latter
472 "*value not available*".
474 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
479 ** Frame filters and frame decorators have been added.
480 ** Temporary breakpoints are now supported.
481 ** Line tables representation has been added.
482 ** New attribute 'parent_type' for gdb.Field objects.
483 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
484 ** New attribute 'name' for gdb.Type objects.
488 Nios II ELF nios2*-*-elf
489 Nios II GNU/Linux nios2*-*-linux
490 Texas Instruments MSP430 msp430*-*-elf
492 * Removed native configurations
494 Support for these a.out NetBSD and OpenBSD obsolete configurations has
495 been removed. ELF variants of these configurations are kept supported.
497 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
498 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
499 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
500 i[34567]86-*-openbsd3.[0-3]
501 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
502 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
503 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
507 Like "catch throw", but catches a re-thrown exception.
509 Renamed from old "maint check-symtabs".
511 Perform consistency checks on symtabs.
513 Expand symtabs matching an optional regexp.
516 Display the details of GDB configure-time options.
518 maint set|show per-command
519 maint set|show per-command space
520 maint set|show per-command time
521 maint set|show per-command symtab
522 Enable display of per-command gdb resource usage.
524 remove-symbol-file FILENAME
525 remove-symbol-file -a ADDRESS
526 Remove a symbol file added via add-symbol-file. The file to remove
527 can be identified by its filename or by an address that lies within
528 the boundaries of this symbol file in memory.
531 info exceptions REGEXP
532 Display the list of Ada exceptions defined in the program being
533 debugged. If provided, only the exceptions whose names match REGEXP
538 set debug symfile off|on
540 Control display of debugging info regarding reading symbol files and
541 symbol tables within those files
543 set print raw frame-arguments
544 show print raw frame-arguments
545 Set/show whether to print frame arguments in raw mode,
546 disregarding any defined pretty-printers.
548 set remote trace-status-packet
549 show remote trace-status-packet
550 Set/show the use of remote protocol qTStatus packet.
554 Control display of debugging messages related to Nios II targets.
558 Control whether target-assisted range stepping is enabled.
560 set startup-with-shell
561 show startup-with-shell
562 Specifies whether Unix child processes are started via a shell or
567 Use the target memory cache for accesses to the code segment. This
568 improves performance of remote debugging (particularly disassembly).
570 * You can now use a literal value 'unlimited' for options that
571 interpret 0 or -1 as meaning "unlimited". E.g., "set
572 trace-buffer-size unlimited" is now an alias for "set
573 trace-buffer-size -1" and "set height unlimited" is now an alias for
576 * The "set debug symtab-create" debugging option of GDB has been changed to
577 accept a verbosity level. 0 means "off", 1 provides basic debugging
578 output, and values of 2 or greater provides more verbose output.
580 * New command-line options
582 Display the details of GDB configure-time options.
584 * The command 'tsave' can now support new option '-ctf' to save trace
585 buffer in Common Trace Format.
587 * Newly installed $prefix/bin/gcore acts as a shell interface for the
590 * GDB now implements the the C++ 'typeid' operator.
592 * The new convenience variable $_exception holds the exception being
593 thrown or caught at an exception-related catchpoint.
595 * The exception-related catchpoints, like "catch throw", now accept a
596 regular expression which can be used to filter exceptions by type.
598 * The new convenience variable $_exitsignal is automatically set to
599 the terminating signal number when the program being debugged dies
600 due to an uncaught signal.
604 ** All MI commands now accept an optional "--language" option.
605 Support for this feature can be verified by using the "-list-features"
606 command, which should contain "language-option".
608 ** The new command -info-gdb-mi-command allows the user to determine
609 whether a GDB/MI command is supported or not.
611 ** The "^error" result record returned when trying to execute an undefined
612 GDB/MI command now provides a variable named "code" whose content is the
613 "undefined-command" error code. Support for this feature can be verified
614 by using the "-list-features" command, which should contain
615 "undefined-command-error-code".
617 ** The -trace-save MI command can optionally save trace buffer in Common
620 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
622 ** The command -data-list-register-values now accepts an optional
623 "--skip-unavailable" option. When used, only the available registers
626 ** The new command -trace-frame-collected dumps collected variables,
627 computed expressions, tvars, memory and registers in a traceframe.
629 ** The commands -stack-list-locals, -stack-list-arguments and
630 -stack-list-variables now accept an option "--skip-unavailable".
631 When used, only the available locals or arguments are displayed.
633 ** The -exec-run command now accepts an optional "--start" option.
634 When used, the command follows the same semantics as the "start"
635 command, stopping the program's execution at the start of its
636 main subprogram. Support for this feature can be verified using
637 the "-list-features" command, which should contain
638 "exec-run-start-option".
640 ** The new commands -catch-assert and -catch-exceptions insert
641 catchpoints stopping the program when Ada exceptions are raised.
643 ** The new command -info-ada-exceptions provides the equivalent of
644 the new "info exceptions" command.
646 * New system-wide configuration scripts
647 A GDB installation now provides scripts suitable for use as system-wide
648 configuration scripts for the following systems:
652 * GDB now supports target-assigned range stepping with remote targets.
653 This improves the performance of stepping source lines by reducing
654 the number of control packets from/to GDB. See "New remote packets"
657 * GDB now understands the element 'tvar' in the XML traceframe info.
658 It has the id of the collected trace state variables.
660 * On S/390 targets that provide the transactional-execution feature,
661 the program interruption transaction diagnostic block (TDB) is now
662 represented as a number of additional "registers" in GDB.
668 The vCont packet supports a new 'r' action, that tells the remote
669 stub to step through an address range itself, without GDB
670 involvemement at each single-step.
672 qXfer:libraries-svr4:read's annex
673 The previously unused annex of the qXfer:libraries-svr4:read packet
674 is now used to support passing an argument list. The remote stub
675 reports support for this argument list to GDB's qSupported query.
676 The defined arguments are "start" and "prev", used to reduce work
677 necessary for library list updating, resulting in significant
680 * New features in the GDB remote stub, GDBserver
682 ** GDBserver now supports target-assisted range stepping. Currently
683 enabled on x86/x86_64 GNU/Linux targets.
685 ** GDBserver now adds element 'tvar' in the XML in the reply to
686 'qXfer:traceframe-info:read'. It has the id of the collected
687 trace state variables.
689 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
692 * New 'z' formatter for printing and examining memory, this displays the
693 value as hexadecimal zero padded on the left to the size of the type.
695 * GDB can now use Windows x64 unwinding data.
697 * The "set remotebaud" command has been replaced by "set serial baud".
698 Similarly, "show remotebaud" has been replaced by "show serial baud".
699 The "set remotebaud" and "show remotebaud" commands are still available
700 to provide backward compatibility with older versions of GDB.
702 *** Changes in GDB 7.6
704 * Target record has been renamed to record-full.
705 Record/replay is now enabled with the "record full" command.
706 This also affects settings that are associated with full record/replay
707 that have been moved from "set/show record" to "set/show record full":
709 set|show record full insn-number-max
710 set|show record full stop-at-limit
711 set|show record full memory-query
713 * A new record target "record-btrace" has been added. The new target
714 uses hardware support to record the control-flow of a process. It
715 does not support replaying the execution, but it implements the
716 below new commands for investigating the recorded execution log.
717 This new recording method can be enabled using:
721 The "record-btrace" target is only available on Intel Atom processors
722 and requires a Linux kernel 2.6.32 or later.
724 * Two new commands have been added for record/replay to give information
725 about the recorded execution without having to replay the execution.
726 The commands are only supported by "record btrace".
728 record instruction-history prints the execution history at
729 instruction granularity
731 record function-call-history prints the execution history at
734 * New native configurations
736 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
737 FreeBSD/powerpc powerpc*-*-freebsd
738 x86_64/Cygwin x86_64-*-cygwin*
739 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
743 ARM AArch64 aarch64*-*-elf
744 ARM AArch64 GNU/Linux aarch64*-*-linux
745 Lynx 178 PowerPC powerpc-*-lynx*178
746 x86_64/Cygwin x86_64-*-cygwin*
747 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
749 * If the configured location of system.gdbinit file (as given by the
750 --with-system-gdbinit option at configure time) is in the
751 data-directory (as specified by --with-gdb-datadir at configure
752 time) or in one of its subdirectories, then GDB will look for the
753 system-wide init file in the directory specified by the
754 --data-directory command-line option.
756 * New command line options:
758 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
759 other initialization files, unlike -nx which disables all of them.
761 * Removed command line options
763 -epoch This was used by the gdb mode in Epoch, an ancient fork of
766 * The 'ptype' and 'whatis' commands now accept an argument to control
769 * 'info proc' now works on some core files.
773 ** Vectors can be created with gdb.Type.vector.
775 ** Python's atexit.register now works in GDB.
777 ** Types can be pretty-printed via a Python API.
779 ** Python 3 is now supported (in addition to Python 2.4 or later)
781 ** New class gdb.Architecture exposes GDB's internal representation
782 of architecture in the Python API.
784 ** New method Frame.architecture returns the gdb.Architecture object
785 corresponding to the frame's architecture.
787 * New Python-based convenience functions:
789 ** $_memeq(buf1, buf2, length)
790 ** $_streq(str1, str2)
792 ** $_regex(str, regex)
794 * The 'cd' command now defaults to using '~' (the home directory) if not
797 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
798 default for GCC since November 2000.
800 * The command 'forward-search' can now be abbreviated as 'fo'.
802 * The command 'info tracepoints' can now display 'installed on target'
803 or 'not installed on target' for each non-pending location of tracepoint.
805 * New configure options
807 --enable-libmcheck/--disable-libmcheck
808 By default, development versions are built with -lmcheck on hosts
809 that support it, in order to help track memory corruption issues.
810 Release versions, on the other hand, are built without -lmcheck
811 by default. The --enable-libmcheck/--disable-libmcheck configure
812 options allow the user to override that default.
813 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
814 This configure option allows the user to build GDB with
815 libbabeltrace using which GDB can read Common Trace Format data.
817 * New commands (for set/show, see "New options" below)
820 Catch signals. This is similar to "handle", but allows commands and
821 conditions to be attached.
824 List the BFDs known to GDB.
826 python-interactive [command]
828 Start a Python interactive prompt, or evaluate the optional command
829 and print the result of expressions.
832 "py" is a new alias for "python".
834 enable type-printer [name]...
835 disable type-printer [name]...
836 Enable or disable type printers.
840 ** For the Renesas Super-H architecture, the "regs" command has been removed
841 (has been deprecated in GDB 7.5), and "info all-registers" should be used
846 set print type methods (on|off)
847 show print type methods
848 Control whether method declarations are displayed by "ptype".
849 The default is to show them.
851 set print type typedefs (on|off)
852 show print type typedefs
853 Control whether typedef definitions are displayed by "ptype".
854 The default is to show them.
856 set filename-display basename|relative|absolute
857 show filename-display
858 Control the way in which filenames is displayed.
859 The default is "relative", which preserves previous behavior.
861 set trace-buffer-size
862 show trace-buffer-size
863 Request target to change the size of trace buffer.
865 set remote trace-buffer-size-packet auto|on|off
866 show remote trace-buffer-size-packet
867 Control the use of the remote protocol `QTBuffer:size' packet.
871 Control display of debugging messages related to ARM AArch64.
874 set debug coff-pe-read
875 show debug coff-pe-read
876 Control display of debugging messages related to reading of COFF/PE
881 Control display of debugging messages related to Mach-O symbols
884 set debug notification
885 show debug notification
886 Control display of debugging info for async remote notification.
890 ** Command parameter changes are now notified using new async record
891 "=cmd-param-changed".
892 ** Trace frame changes caused by command "tfind" are now notified using
893 new async record "=traceframe-changed".
894 ** The creation, deletion and modification of trace state variables
895 are now notified using new async records "=tsv-created",
896 "=tsv-deleted" and "=tsv-modified".
897 ** The start and stop of process record are now notified using new
898 async record "=record-started" and "=record-stopped".
899 ** Memory changes are now notified using new async record
901 ** The data-disassemble command response will include a "fullname" field
902 containing the absolute file name when source has been requested.
903 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
904 command, to allow pattern filling of memory areas.
905 ** New commands "-catch-load"/"-catch-unload" added for intercepting
906 library load/unload events.
907 ** The response to breakpoint commands and breakpoint async records
908 includes an "installed" field containing a boolean state about each
909 non-pending tracepoint location is whether installed on target or not.
910 ** Output of the "-trace-status" command includes a "trace-file" field
911 containing the name of the trace file being examined. This field is
912 optional, and only present when examining a trace file.
913 ** The "fullname" field is now always present along with the "file" field,
914 even if the file cannot be found by GDB.
916 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
917 You must have the LZMA library available when configuring GDB for this
918 feature to be enabled. For more information, see:
919 http://fedoraproject.org/wiki/Features/MiniDebugInfo
924 Set the size of trace buffer. The remote stub reports support for this
925 packet to gdb's qSupported query.
928 Enable Branch Trace Store (BTS)-based branch tracing for the current
929 thread. The remote stub reports support for this packet to gdb's
933 Disable branch tracing for the current thread. The remote stub reports
934 support for this packet to gdb's qSupported query.
937 Read the traced branches for the current thread. The remote stub
938 reports support for this packet to gdb's qSupported query.
940 *** Changes in GDB 7.5
942 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
943 for more x32 ABI info.
945 * GDB now supports access to MIPS DSP registers on Linux targets.
947 * GDB now supports debugging microMIPS binaries.
949 * The "info os" command on GNU/Linux can now display information on
950 several new classes of objects managed by the operating system:
951 "info os procgroups" lists process groups
952 "info os files" lists file descriptors
953 "info os sockets" lists internet-domain sockets
954 "info os shm" lists shared-memory regions
955 "info os semaphores" lists semaphores
956 "info os msg" lists message queues
957 "info os modules" lists loaded kernel modules
959 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
960 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
961 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
962 options and inspect the probe arguments using the new $_probe_arg family
963 of convenience variables. You can obtain more information about SystemTap
964 in <http://sourceware.org/systemtap/>.
966 * GDB now supports reversible debugging on ARM, it allows you to
967 debug basic ARM and THUMB instructions, and provides
968 record/replay support.
970 * The option "symbol-reloading" has been deleted as it is no longer used.
974 ** GDB commands implemented in Python can now be put in command class
977 ** The "maint set python print-stack on|off" is now deleted.
979 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
980 apply "flag enum"-style pretty-printing to any enum.
982 ** gdb.lookup_symbol can now work when there is no current frame.
984 ** gdb.Symbol now has a 'line' attribute, holding the line number in
985 the source at which the symbol was defined.
987 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
988 method 'value'. The former indicates whether the symbol needs a
989 frame in order to compute its value, and the latter computes the
992 ** A new method 'referenced_value' on gdb.Value objects which can
993 dereference pointer as well as C++ reference values.
995 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
996 which return the global and static blocks (as gdb.Block objects),
997 of the underlying symbol table, respectively.
999 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1000 object associated with a PC value.
1002 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1003 of the address range occupied by code for the current source line.
1005 * Go language support.
1006 GDB now supports debugging programs written in the Go programming
1009 * GDBserver now supports stdio connections.
1010 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1012 * The binary "gdbtui" can no longer be built or installed.
1013 Use "gdb -tui" instead.
1015 * GDB will now print "flag" enums specially. A flag enum is one where
1016 all the enumerator values have no bits in common when pairwise
1017 "and"ed. When printing a value whose type is a flag enum, GDB will
1018 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1019 (gdb) print (enum E) 3
1022 * The filename part of a linespec will now match trailing components
1023 of a source file name. For example, "break gcc/expr.c:1000" will
1024 now set a breakpoint in build/gcc/expr.c, but not
1025 build/libcpp/expr.c.
1027 * The "info proc" and "generate-core-file" commands will now also
1028 work on remote targets connected to GDBserver on Linux.
1030 * The command "info catch" has been removed. It has been disabled
1031 since December 2007.
1033 * The "catch exception" and "catch assert" commands now accept
1034 a condition at the end of the command, much like the "break"
1035 command does. For instance:
1037 (gdb) catch exception Constraint_Error if Barrier = True
1039 Previously, it was possible to add a condition to such catchpoints,
1040 but it had to be done as a second step, after the catchpoint had been
1041 created, using the "condition" command.
1043 * The "info static-tracepoint-marker" command will now also work on
1044 native Linux targets with in-process agent.
1046 * GDB can now set breakpoints on inlined functions.
1048 * The .gdb_index section has been updated to include symbols for
1049 inlined functions. GDB will ignore older .gdb_index sections by
1050 default, which could cause symbol files to be loaded more slowly
1051 until their .gdb_index sections can be recreated. The new command
1052 "set use-deprecated-index-sections on" will cause GDB to use any older
1053 .gdb_index sections it finds. This will restore performance, but the
1054 ability to set breakpoints on inlined functions will be lost in symbol
1055 files with older .gdb_index sections.
1057 The .gdb_index section has also been updated to record more information
1058 about each symbol. This speeds up the "info variables", "info functions"
1059 and "info types" commands when used with programs having the .gdb_index
1060 section, as well as speeding up debugging with shared libraries using
1061 the .gdb_index section.
1063 * Ada support for GDB/MI Variable Objects has been added.
1065 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1070 ** New command -info-os is the MI equivalent of "info os".
1072 ** Output logs ("set logging" and related) now include MI output.
1076 ** "set use-deprecated-index-sections on|off"
1077 "show use-deprecated-index-sections on|off"
1078 Controls the use of deprecated .gdb_index sections.
1080 ** "catch load" and "catch unload" can be used to stop when a shared
1081 library is loaded or unloaded, respectively.
1083 ** "enable count" can be used to auto-disable a breakpoint after
1086 ** "info vtbl" can be used to show the virtual method tables for
1087 C++ and Java objects.
1089 ** "explore" and its sub commands "explore value" and "explore type"
1090 can be used to recursively explore values and types of
1091 expressions. These commands are available only if GDB is
1092 configured with '--with-python'.
1094 ** "info auto-load" shows status of all kinds of auto-loaded files,
1095 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1096 sequences of commands files, "info auto-load python-scripts"
1097 shows status of auto-loading Python script files,
1098 "info auto-load local-gdbinit" shows status of loading init file
1099 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1100 status of inferior specific thread debugging shared library loading.
1102 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1103 and "show auto-load-scripts" commands have been deprecated, use their
1104 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1105 and "show auto-load python-scripts" counterparts instead.
1107 ** "dprintf location,format,args..." creates a dynamic printf, which
1108 is basically a breakpoint that does a printf and immediately
1109 resumes your program's execution, so it is like a printf that you
1110 can insert dynamically at runtime instead of at compiletime.
1112 ** "set print symbol"
1114 Controls whether GDB attempts to display the symbol, if any,
1115 corresponding to addresses it prints. This defaults to "on", but
1116 you can set it to "off" to restore GDB's previous behavior.
1118 * Deprecated commands
1120 ** For the Renesas Super-H architecture, the "regs" command has been
1121 deprecated, and "info all-registers" should be used instead.
1125 Renesas RL78 rl78-*-elf
1126 HP OpenVMS ia64 ia64-hp-openvms*
1128 * GDBserver supports evaluation of breakpoint conditions. When
1129 support is advertised by GDBserver, GDB may be told to send the
1130 breakpoint conditions in bytecode form to GDBserver. GDBserver
1131 will only report the breakpoint trigger to GDB when its condition
1136 set mips compression
1137 show mips compression
1138 Select the compressed ISA encoding used in functions that have no symbol
1139 information available. The encoding can be set to either of:
1142 and is updated automatically from ELF file flags if available.
1144 set breakpoint condition-evaluation
1145 show breakpoint condition-evaluation
1146 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1147 GDBserver ("target"). Default option "auto" chooses the most efficient
1149 This option can improve debugger efficiency depending on the speed of the
1153 Disable auto-loading globally.
1156 Show auto-loading setting of all kinds of auto-loaded files.
1158 set auto-load gdb-scripts on|off
1159 show auto-load gdb-scripts
1160 Control auto-loading of GDB canned sequences of commands files.
1162 set auto-load python-scripts on|off
1163 show auto-load python-scripts
1164 Control auto-loading of Python script files.
1166 set auto-load local-gdbinit on|off
1167 show auto-load local-gdbinit
1168 Control loading of init file (.gdbinit) from current directory.
1170 set auto-load libthread-db on|off
1171 show auto-load libthread-db
1172 Control auto-loading of inferior specific thread debugging shared library.
1174 set auto-load scripts-directory <dir1>[:<dir2>...]
1175 show auto-load scripts-directory
1176 Set a list of directories from which to load auto-loaded scripts.
1177 Automatically loaded Python scripts and GDB scripts are located in one
1178 of the directories listed by this option.
1179 The delimiter (':' above) may differ according to the host platform.
1181 set auto-load safe-path <dir1>[:<dir2>...]
1182 show auto-load safe-path
1183 Set a list of directories from which it is safe to auto-load files.
1184 The delimiter (':' above) may differ according to the host platform.
1186 set debug auto-load on|off
1187 show debug auto-load
1188 Control display of debugging info for auto-loading the files above.
1190 set dprintf-style gdb|call|agent
1192 Control the way in which a dynamic printf is performed; "gdb"
1193 requests a GDB printf command, while "call" causes dprintf to call a
1194 function in the inferior. "agent" requests that the target agent
1195 (such as GDBserver) do the printing.
1197 set dprintf-function <expr>
1198 show dprintf-function
1199 set dprintf-channel <expr>
1200 show dprintf-channel
1201 Set the function and optional first argument to the call when using
1202 the "call" style of dynamic printf.
1204 set disconnected-dprintf on|off
1205 show disconnected-dprintf
1206 Control whether agent-style dynamic printfs continue to be in effect
1207 after GDB disconnects.
1209 * New configure options
1211 --with-auto-load-dir
1212 Configure default value for the 'set auto-load scripts-directory'
1213 setting above. It defaults to '$debugdir:$datadir/auto-load',
1214 $debugdir representing global debugging info directories (available
1215 via 'show debug-file-directory') and $datadir representing GDB's data
1216 directory (available via 'show data-directory').
1218 --with-auto-load-safe-path
1219 Configure default value for the 'set auto-load safe-path' setting
1220 above. It defaults to the --with-auto-load-dir setting.
1222 --without-auto-load-safe-path
1223 Set 'set auto-load safe-path' to '/', effectively disabling this
1226 * New remote packets
1228 z0/z1 conditional breakpoints extension
1230 The z0/z1 breakpoint insertion packets have been extended to carry
1231 a list of conditional expressions over to the remote stub depending on the
1232 condition evaluation mode. The use of this extension can be controlled
1233 via the "set remote conditional-breakpoints-packet" command.
1237 Specify the signals which the remote stub may pass to the debugged
1238 program without GDB involvement.
1240 * New command line options
1242 --init-command=FILE, -ix Like --command, -x but execute it
1243 before loading inferior.
1244 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1245 execute it before loading inferior.
1247 *** Changes in GDB 7.4
1249 * GDB now handles ambiguous linespecs more consistently; the existing
1250 FILE:LINE support has been expanded to other types of linespecs. A
1251 breakpoint will now be set on all matching locations in all
1252 inferiors, and locations will be added or removed according to
1255 * GDB now allows you to skip uninteresting functions and files when
1256 stepping with the "skip function" and "skip file" commands.
1258 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1259 and "show remote hardware-watchpoint-length-limit". These allows to
1260 set or show the maximum length limit (in bytes) of a remote
1261 target hardware watchpoint.
1263 This allows e.g. to use "unlimited" hardware watchpoints with the
1264 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1265 watchpoints are slower than real hardware watchpoints but are
1266 significantly faster than gdb software watchpoints.
1270 ** The register_pretty_printer function in module gdb.printing now takes
1271 an optional `replace' argument. If True, the new printer replaces any
1274 ** The "maint set python print-stack on|off" command has been
1275 deprecated and will be deleted in GDB 7.5.
1276 A new command: "set python print-stack none|full|message" has
1277 replaced it. Additionally, the default for "print-stack" is
1278 now "message", which just prints the error message without
1281 ** A prompt substitution hook (prompt_hook) is now available to the
1284 ** A new Python module, gdb.prompt has been added to the GDB Python
1285 modules library. This module provides functionality for
1286 escape sequences in prompts (used by set/show
1287 extended-prompt). These escape sequences are replaced by their
1288 corresponding value.
1290 ** Python commands and convenience-functions located in
1291 'data-directory'/python/gdb/command and
1292 'data-directory'/python/gdb/function are now automatically loaded
1295 ** Blocks now provide four new attributes. global_block and
1296 static_block will return the global and static blocks
1297 respectively. is_static and is_global are boolean attributes
1298 that indicate if the block is one of those two types.
1300 ** Symbols now provide the "type" attribute, the type of the symbol.
1302 ** The "gdb.breakpoint" function has been deprecated in favor of
1305 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1306 of a function. This class is based on the "finish" command
1307 available in the CLI.
1309 ** Type objects for struct and union types now allow access to
1310 the fields using standard Python dictionary (mapping) methods.
1311 For example, "some_type['myfield']" now works, as does
1312 "some_type.items()".
1314 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1317 ** A new function, "deep_items" has been added to the gdb.types
1318 module in the GDB Python modules library. This function returns
1319 an iterator over the fields of a struct or union type. Unlike
1320 the standard Python "iteritems" method, it will recursively traverse
1321 any anonymous fields.
1325 ** "*stopped" events can report several new "reason"s, such as
1328 ** Breakpoint changes are now notified using new async records, like
1329 "=breakpoint-modified".
1331 ** New command -ada-task-info.
1333 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1334 $sdir specifies the default system locations of shared libraries.
1335 $pdir specifies the directory where the libpthread used by the application
1338 GDB no longer looks in $sdir and $pdir after it has searched the directories
1339 mentioned in libthread-db-search-path. If you want to search those
1340 directories, they must be specified in libthread-db-search-path.
1341 The default value of libthread-db-search-path on GNU/Linux and Solaris
1342 systems is now "$sdir:$pdir".
1344 $pdir is not supported by gdbserver, it is currently ignored.
1345 $sdir is supported by gdbserver.
1347 * New configure option --with-iconv-bin.
1348 When using the internationalization support like the one in the GNU C
1349 library, GDB will invoke the "iconv" program to get a list of supported
1350 character sets. If this program lives in a non-standard location, one can
1351 use this option to specify where to find it.
1353 * When natively debugging programs on PowerPC BookE processors running
1354 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1355 watchpoints, which specify a mask in addition to an address to watch.
1356 The mask specifies that some bits of an address (the bits which are
1357 reset in the mask) should be ignored when matching the address accessed
1358 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1359 section in the user manual for more details.
1361 * The new option --once causes GDBserver to stop listening for connections once
1362 the first connection is made. The listening port used by GDBserver will
1363 become available after that.
1365 * New commands "info macros" and "alias" have been added.
1367 * New function parameters suffix @entry specifies value of function parameter
1368 at the time the function got called. Entry values are available only since
1374 "!" is now an alias of the "shell" command.
1375 Note that no space is needed between "!" and SHELL COMMAND.
1379 watch EXPRESSION mask MASK_VALUE
1380 The watch command now supports the mask argument which allows creation
1381 of masked watchpoints, if the current architecture supports this feature.
1383 info auto-load-scripts [REGEXP]
1384 This command was formerly named "maintenance print section-scripts".
1385 It is now generally useful and is no longer a maintenance-only command.
1387 info macro [-all] [--] MACRO
1388 The info macro command has new options `-all' and `--'. The first for
1389 printing all definitions of a macro. The second for explicitly specifying
1390 the end of arguments and the beginning of the macro name in case the macro
1391 name starts with a hyphen.
1393 collect[/s] EXPRESSIONS
1394 The tracepoint collect command now takes an optional modifier "/s"
1395 that directs it to dereference pointer-to-character types and
1396 collect the bytes of memory up to a zero byte. The behavior is
1397 similar to what you see when you use the regular print command on a
1398 string. An optional integer following the "/s" sets a bound on the
1399 number of bytes that will be collected.
1402 The trace start command now interprets any supplied arguments as a
1403 note to be recorded with the trace run, with an effect similar to
1404 setting the variable trace-notes.
1407 The trace stop command now interprets any arguments as a note to be
1408 mentioned along with the tstatus report that the trace was stopped
1409 with a command. The effect is similar to setting the variable
1412 * Tracepoints can now be enabled and disabled at any time after a trace
1413 experiment has been started using the standard "enable" and "disable"
1414 commands. It is now possible to start a trace experiment with no enabled
1415 tracepoints; GDB will display a warning, but will allow the experiment to
1416 begin, assuming that tracepoints will be enabled as needed while the trace
1419 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1420 locations with 4-byte instructions, when they were previously
1421 limited to locations with instructions of 5 bytes or longer.
1425 set debug dwarf2-read
1426 show debug dwarf2-read
1427 Turns on or off display of debugging messages related to reading
1428 DWARF debug info. The default is off.
1430 set debug symtab-create
1431 show debug symtab-create
1432 Turns on or off display of debugging messages related to symbol table
1433 creation. The default is off.
1436 show extended-prompt
1437 Set the GDB prompt, and allow escape sequences to be inserted to
1438 display miscellaneous information (see 'help set extended-prompt'
1439 for the list of sequences). This prompt (and any information
1440 accessed through the escape sequences) is updated every time the
1441 prompt is displayed.
1443 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1444 show print entry-values
1445 Set printing of frame argument values at function entry. In some cases
1446 GDB can determine the value of function argument which was passed by the
1447 function caller, even if the value was modified inside the called function.
1449 set debug entry-values
1450 show debug entry-values
1451 Control display of debugging info for determining frame argument values at
1452 function entry and virtual tail call frames.
1454 set basenames-may-differ
1455 show basenames-may-differ
1456 Set whether a source file may have multiple base names.
1457 (A "base name" is the name of a file with the directory part removed.
1458 Example: The base name of "/home/user/hello.c" is "hello.c".)
1459 If set, GDB will canonicalize file names (e.g., expand symlinks)
1460 before comparing them. Canonicalization is an expensive operation,
1461 but it allows the same file be known by more than one base name.
1462 If not set (the default), all source files are assumed to have just
1463 one base name, and gdb will do file name comparisons more efficiently.
1469 Set a user name and notes for the current and any future trace runs.
1470 This is useful for long-running and/or disconnected traces, to
1471 inform others (or yourself) as to who is running the trace, supply
1472 contact information, or otherwise explain what is going on.
1474 set trace-stop-notes
1475 show trace-stop-notes
1476 Set a note attached to the trace run, that is displayed when the
1477 trace has been stopped by a tstop command. This is useful for
1478 instance as an explanation, if you are stopping a trace run that was
1479 started by someone else.
1481 * New remote packets
1485 Dynamically enable a tracepoint in a started trace experiment.
1489 Dynamically disable a tracepoint in a started trace experiment.
1493 Set the user and notes of the trace run.
1497 Query the current status of a tracepoint.
1501 Query the minimum length of instruction at which a fast tracepoint may
1504 * Dcache size (number of lines) and line-size are now runtime-configurable
1505 via "set dcache line" and "set dcache line-size" commands.
1509 Texas Instruments TMS320C6x tic6x-*-*
1513 Renesas RL78 rl78-*-elf
1515 *** Changes in GDB 7.3.1
1517 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1519 *** Changes in GDB 7.3
1521 * GDB has a new command: "thread find [REGEXP]".
1522 It finds the thread id whose name, target id, or thread extra info
1523 matches the given regular expression.
1525 * The "catch syscall" command now works on mips*-linux* targets.
1527 * The -data-disassemble MI command now supports modes 2 and 3 for
1528 dumping the instruction opcodes.
1530 * New command line options
1532 -data-directory DIR Specify DIR as the "data-directory".
1533 This is mostly for testing purposes.
1535 * The "maint set python auto-load on|off" command has been renamed to
1536 "set auto-load-scripts on|off".
1538 * GDB has a new command: "set directories".
1539 It is like the "dir" command except that it replaces the
1540 source path list instead of augmenting it.
1542 * GDB now understands thread names.
1544 On GNU/Linux, "info threads" will display the thread name as set by
1545 prctl or pthread_setname_np.
1547 There is also a new command, "thread name", which can be used to
1548 assign a name internally for GDB to display.
1551 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1552 has been integrated into GDB.
1556 ** The function gdb.Write now accepts an optional keyword 'stream'.
1557 This keyword, when provided, will direct the output to either
1558 stdout, stderr, or GDB's logging output.
1560 ** Parameters can now be be sub-classed in Python, and in particular
1561 you may implement the get_set_doc and get_show_doc functions.
1562 This improves how Parameter set/show documentation is processed
1563 and allows for more dynamic content.
1565 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1566 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1567 have an is_valid method.
1569 ** Breakpoints can now be sub-classed in Python, and in particular
1570 you may implement a 'stop' function that is executed each time
1571 the inferior reaches that breakpoint.
1573 ** New function gdb.lookup_global_symbol looks up a global symbol.
1575 ** GDB values in Python are now callable if the value represents a
1576 function. For example, if 'some_value' represents a function that
1577 takes two integer parameters and returns a value, you can call
1578 that function like so:
1580 result = some_value (10,20)
1582 ** Module gdb.types has been added.
1583 It contains a collection of utilities for working with gdb.Types objects:
1584 get_basic_type, has_field, make_enum_dict.
1586 ** Module gdb.printing has been added.
1587 It contains utilities for writing and registering pretty-printers.
1588 New classes: PrettyPrinter, SubPrettyPrinter,
1589 RegexpCollectionPrettyPrinter.
1590 New function: register_pretty_printer.
1592 ** New commands "info pretty-printers", "enable pretty-printer" and
1593 "disable pretty-printer" have been added.
1595 ** gdb.parameter("directories") is now available.
1597 ** New function gdb.newest_frame returns the newest frame in the
1600 ** The gdb.InferiorThread class has a new "name" attribute. This
1601 holds the thread's name.
1603 ** Python Support for Inferior events.
1604 Python scripts can add observers to be notified of events
1605 occurring in the process being debugged.
1606 The following events are currently supported:
1607 - gdb.events.cont Continue event.
1608 - gdb.events.exited Inferior exited event.
1609 - gdb.events.stop Signal received, and Breakpoint hit events.
1613 ** GDB now puts template parameters in scope when debugging in an
1614 instantiation. For example, if you have:
1616 template<int X> int func (void) { return X; }
1618 then if you step into func<5>, "print X" will show "5". This
1619 feature requires proper debuginfo support from the compiler; it
1620 was added to GCC 4.5.
1622 ** The motion commands "next", "finish", "until", and "advance" now
1623 work better when exceptions are thrown. In particular, GDB will
1624 no longer lose control of the inferior; instead, the GDB will
1625 stop the inferior at the point at which the exception is caught.
1626 This functionality requires a change in the exception handling
1627 code that was introduced in GCC 4.5.
1629 * GDB now follows GCC's rules on accessing volatile objects when
1630 reading or writing target state during expression evaluation.
1631 One notable difference to prior behavior is that "print x = 0"
1632 no longer generates a read of x; the value of the assignment is
1633 now always taken directly from the value being assigned.
1635 * GDB now has some support for using labels in the program's source in
1636 linespecs. For instance, you can use "advance label" to continue
1637 execution to a label.
1639 * GDB now has support for reading and writing a new .gdb_index
1640 section. This section holds a fast index of DWARF debugging
1641 information and can be used to greatly speed up GDB startup and
1642 operation. See the documentation for `save gdb-index' for details.
1644 * The "watch" command now accepts an optional "-location" argument.
1645 When used, this causes GDB to watch the memory referred to by the
1646 expression. Such a watchpoint is never deleted due to it going out
1649 * GDB now supports thread debugging of core dumps on GNU/Linux.
1651 GDB now activates thread debugging using the libthread_db library
1652 when debugging GNU/Linux core dumps, similarly to when debugging
1653 live processes. As a result, when debugging a core dump file, GDB
1654 is now able to display pthread_t ids of threads. For example, "info
1655 threads" shows the same output as when debugging the process when it
1656 was live. In earlier releases, you'd see something like this:
1659 * 1 LWP 6780 main () at main.c:10
1661 While now you see this:
1664 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1666 It is also now possible to inspect TLS variables when debugging core
1669 When debugging a core dump generated on a machine other than the one
1670 used to run GDB, you may need to point GDB at the correct
1671 libthread_db library with the "set libthread-db-search-path"
1672 command. See the user manual for more details on this command.
1674 * When natively debugging programs on PowerPC BookE processors running
1675 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1676 which stop execution of the inferior whenever it executes an instruction
1677 at any address within the specified range. See the "PowerPC Embedded"
1678 section in the user manual for more details.
1680 * New features in the GDB remote stub, GDBserver
1682 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1683 and i686 LynxOS (version 5.x).
1685 ** GDBserver is now supported on Blackfin Linux.
1687 * New native configurations
1689 ia64 HP-UX ia64-*-hpux*
1693 Analog Devices, Inc. Blackfin Processor bfin-*
1695 * Ada task switching is now supported on sparc-elf targets when
1696 debugging a program using the Ravenscar Profile. For more information,
1697 see the "Tasking Support when using the Ravenscar Profile" section
1698 in the GDB user manual.
1700 * Guile support was removed.
1702 * New features in the GNU simulator
1704 ** The --map-info flag lists all known core mappings.
1706 ** CFI flashes may be simulated via the "cfi" device.
1708 *** Changes in GDB 7.2
1710 * Shared library support for remote targets by default
1712 When GDB is configured for a generic, non-OS specific target, like
1713 for example, --target=arm-eabi or one of the many *-*-elf targets,
1714 GDB now queries remote stubs for loaded shared libraries using the
1715 `qXfer:libraries:read' packet. Previously, shared library support
1716 was always disabled for such configurations.
1720 ** Argument Dependent Lookup (ADL)
1722 In C++ ADL lookup directs function search to the namespaces of its
1723 arguments even if the namespace has not been imported.
1733 Here the compiler will search for `foo' in the namespace of 'b'
1734 and find A::foo. GDB now supports this. This construct is commonly
1735 used in the Standard Template Library for operators.
1737 ** Improved User Defined Operator Support
1739 In addition to member operators, GDB now supports lookup of operators
1740 defined in a namespace and imported with a `using' directive, operators
1741 defined in the global scope, operators imported implicitly from an
1742 anonymous namespace, and the ADL operators mentioned in the previous
1744 GDB now also supports proper overload resolution for all the previously
1745 mentioned flavors of operators.
1747 ** static const class members
1749 Printing of static const class members that are initialized in the
1750 class definition has been fixed.
1752 * Windows Thread Information Block access.
1754 On Windows targets, GDB now supports displaying the Windows Thread
1755 Information Block (TIB) structure. This structure is visible either
1756 by using the new command `info w32 thread-information-block' or, by
1757 dereferencing the new convenience variable named `$_tlb', a
1758 thread-specific pointer to the TIB. This feature is also supported
1759 when remote debugging using GDBserver.
1761 * Static tracepoints
1763 Static tracepoints are calls in the user program into a tracing
1764 library. One such library is a port of the LTTng kernel tracer to
1765 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1766 When debugging with GDBserver, GDB now supports combining the GDB
1767 tracepoint machinery with such libraries. For example: the user can
1768 use GDB to probe a static tracepoint marker (a call from the user
1769 program into the tracing library) with the new "strace" command (see
1770 "New commands" below). This creates a "static tracepoint" in the
1771 breakpoint list, that can be manipulated with the same feature set
1772 as fast and regular tracepoints. E.g., collect registers, local and
1773 global variables, collect trace state variables, and define
1774 tracepoint conditions. In addition, the user can collect extra
1775 static tracepoint marker specific data, by collecting the new
1776 $_sdata internal variable. When analyzing the trace buffer, you can
1777 inspect $_sdata like any other variable available to GDB. For more
1778 information, see the "Tracepoints" chapter in GDB user manual. New
1779 remote packets have been defined to support static tracepoints, see
1780 the "New remote packets" section below.
1782 * Better reconstruction of tracepoints after disconnected tracing
1784 GDB will attempt to download the original source form of tracepoint
1785 definitions when starting a trace run, and then will upload these
1786 upon reconnection to the target, resulting in a more accurate
1787 reconstruction of the tracepoints that are in use on the target.
1791 You can now exercise direct control over the ways that GDB can
1792 affect your program. For instance, you can disallow the setting of
1793 breakpoints, so that the program can run continuously (assuming
1794 non-stop mode). In addition, the "observer" variable is available
1795 to switch all of the different controls; in observer mode, GDB
1796 cannot affect the target's behavior at all, which is useful for
1797 tasks like diagnosing live systems in the field.
1799 * The new convenience variable $_thread holds the number of the
1802 * New remote packets
1806 Return the address of the Windows Thread Information Block of a given thread.
1810 In response to several of the tracepoint packets, the target may now
1811 also respond with a number of intermediate `qRelocInsn' request
1812 packets before the final result packet, to have GDB handle
1813 relocating an instruction to execute at a different address. This
1814 is particularly useful for stubs that support fast tracepoints. GDB
1815 reports support for this feature in the qSupported packet.
1819 List static tracepoint markers in the target program.
1823 List static tracepoint markers at a given address in the target
1826 qXfer:statictrace:read
1828 Read the static trace data collected (by a `collect $_sdata'
1829 tracepoint action). The remote stub reports support for this packet
1830 to gdb's qSupported query.
1834 Send the current settings of GDB's permission flags.
1838 Send part of the source (textual) form of a tracepoint definition,
1839 which includes location, conditional, and action list.
1841 * The source command now accepts a -s option to force searching for the
1842 script in the source search path even if the script name specifies
1845 * New features in the GDB remote stub, GDBserver
1847 - GDBserver now support tracepoints (including fast tracepoints, and
1848 static tracepoints). The feature is currently supported by the
1849 i386-linux and amd64-linux builds. See the "Tracepoints support
1850 in gdbserver" section in the manual for more information.
1852 GDBserver JIT compiles the tracepoint's conditional agent
1853 expression bytecode into native code whenever possible for low
1854 overhead dynamic tracepoints conditionals. For such tracepoints,
1855 an expression that examines program state is evaluated when the
1856 tracepoint is reached, in order to determine whether to capture
1857 trace data. If the condition is simple and false, processing the
1858 tracepoint finishes very quickly and no data is gathered.
1860 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1861 for static tracepoints support.
1863 - GDBserver now supports x86_64 Windows 64-bit debugging.
1865 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1866 it understands register description.
1868 * The --batch flag now disables pagination and queries.
1870 * X86 general purpose registers
1872 GDB now supports reading/writing byte, word and double-word x86
1873 general purpose registers directly. This means you can use, say,
1874 $ah or $ax to refer, respectively, to the byte register AH and
1875 16-bit word register AX that are actually portions of the 32-bit
1876 register EAX or 64-bit register RAX.
1878 * The `commands' command now accepts a range of breakpoints to modify.
1879 A plain `commands' following a command that creates multiple
1880 breakpoints affects all the breakpoints set by that command. This
1881 applies to breakpoints set by `rbreak', and also applies when a
1882 single `break' command creates multiple breakpoints (e.g.,
1883 breakpoints on overloaded c++ functions).
1885 * The `rbreak' command now accepts a filename specification as part of
1886 its argument, limiting the functions selected by the regex to those
1887 in the specified file.
1889 * Support for remote debugging Windows and SymbianOS shared libraries
1890 from Unix hosts has been improved. Non Windows GDB builds now can
1891 understand target reported file names that follow MS-DOS based file
1892 system semantics, such as file names that include drive letters and
1893 use the backslash character as directory separator. This makes it
1894 possible to transparently use the "set sysroot" and "set
1895 solib-search-path" on Unix hosts to point as host copies of the
1896 target's shared libraries. See the new command "set
1897 target-file-system-kind" described below, and the "Commands to
1898 specify files" section in the user manual for more information.
1902 eval template, expressions...
1903 Convert the values of one or more expressions under the control
1904 of the string template to a command line, and call it.
1906 set target-file-system-kind unix|dos-based|auto
1907 show target-file-system-kind
1908 Set or show the assumed file system kind for target reported file
1911 save breakpoints <filename>
1912 Save all current breakpoint definitions to a file suitable for use
1913 in a later debugging session. To read the saved breakpoint
1914 definitions, use the `source' command.
1916 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1919 info static-tracepoint-markers
1920 Display information about static tracepoint markers in the target.
1922 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1923 Define a static tracepoint by probing a marker at the given
1924 function, line, address, or marker ID.
1928 Enable and disable observer mode.
1930 set may-write-registers on|off
1931 set may-write-memory on|off
1932 set may-insert-breakpoints on|off
1933 set may-insert-tracepoints on|off
1934 set may-insert-fast-tracepoints on|off
1935 set may-interrupt on|off
1936 Set individual permissions for GDB effects on the target. Note that
1937 some of these settings can have undesirable or surprising
1938 consequences, particularly when changed in the middle of a session.
1939 For instance, disabling the writing of memory can prevent
1940 breakpoints from being inserted, cause single-stepping to fail, or
1941 even crash your program, if you disable after breakpoints have been
1942 inserted. However, GDB should not crash.
1944 set record memory-query on|off
1945 show record memory-query
1946 Control whether to stop the inferior if memory changes caused
1947 by an instruction cannot be recorded.
1952 The disassemble command now supports "start,+length" form of two arguments.
1956 ** GDB now provides a new directory location, called the python directory,
1957 where Python scripts written for GDB can be installed. The location
1958 of that directory is <data-directory>/python, where <data-directory>
1959 is the GDB data directory. For more details, see section `Scripting
1960 GDB using Python' in the manual.
1962 ** The GDB Python API now has access to breakpoints, symbols, symbol
1963 tables, program spaces, inferiors, threads and frame's code blocks.
1964 Additionally, GDB Parameters can now be created from the API, and
1965 manipulated via set/show in the CLI.
1967 ** New functions gdb.target_charset, gdb.target_wide_charset,
1968 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1970 ** New exception gdb.GdbError.
1972 ** Pretty-printers are now also looked up in the current program space.
1974 ** Pretty-printers can now be individually enabled and disabled.
1976 ** GDB now looks for names of Python scripts to auto-load in a
1977 special section named `.debug_gdb_scripts', in addition to looking
1978 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1980 * Tracepoint actions were unified with breakpoint commands. In particular,
1981 there are no longer differences in "info break" output for breakpoints and
1982 tracepoints and the "commands" command can be used for both tracepoints and
1983 regular breakpoints.
1987 ARM Symbian arm*-*-symbianelf*
1989 * D language support.
1990 GDB now supports debugging programs written in the D programming
1993 * GDB now supports the extended ptrace interface for PowerPC which is
1994 available since Linux kernel version 2.6.34. This automatically enables
1995 any hardware breakpoints and additional hardware watchpoints available in
1996 the processor. The old ptrace interface exposes just one hardware
1997 watchpoint and no hardware breakpoints.
1999 * GDB is now able to use the Data Value Compare (DVC) register available on
2000 embedded PowerPC processors to implement in hardware simple watchpoint
2001 conditions of the form:
2003 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2005 This works in native GDB running on Linux kernels with the extended ptrace
2006 interface mentioned above.
2008 *** Changes in GDB 7.1
2012 ** Namespace Support
2014 GDB now supports importing of namespaces in C++. This enables the
2015 user to inspect variables from imported namespaces. Support for
2016 namepace aliasing has also been added. So, if a namespace is
2017 aliased in the current scope (e.g. namepace C=A; ) the user can
2018 print variables using the alias (e.g. (gdb) print C::x).
2022 All known bugs relating to the printing of virtual base class were
2023 fixed. It is now possible to call overloaded static methods using a
2028 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2029 and reinterpret_cast<> are now handled by the C++ expression parser.
2033 Xilinx MicroBlaze microblaze-*-*
2038 Xilinx MicroBlaze microblaze
2041 * Multi-program debugging.
2043 GDB now has support for multi-program (a.k.a. multi-executable or
2044 multi-exec) debugging. This allows for debugging multiple inferiors
2045 simultaneously each running a different program under the same GDB
2046 session. See "Debugging Multiple Inferiors and Programs" in the
2047 manual for more information. This implied some user visible changes
2048 in the multi-inferior support. For example, "info inferiors" now
2049 lists inferiors that are not running yet or that have exited
2050 already. See also "New commands" and "New options" below.
2052 * New tracing features
2054 GDB's tracepoint facility now includes several new features:
2056 ** Trace state variables
2058 GDB tracepoints now include support for trace state variables, which
2059 are variables managed by the target agent during a tracing
2060 experiment. They are useful for tracepoints that trigger each
2061 other, so for instance one tracepoint can count hits in a variable,
2062 and then a second tracepoint has a condition that is true when the
2063 count reaches a particular value. Trace state variables share the
2064 $-syntax of GDB convenience variables, and can appear in both
2065 tracepoint actions and condition expressions. Use the "tvariable"
2066 command to create, and "info tvariables" to view; see "Trace State
2067 Variables" in the manual for more detail.
2071 GDB now includes an option for defining fast tracepoints, which
2072 targets may implement more efficiently, such as by installing a jump
2073 into the target agent rather than a trap instruction. The resulting
2074 speedup can be by two orders of magnitude or more, although the
2075 tradeoff is that some program locations on some target architectures
2076 might not allow fast tracepoint installation, for instance if the
2077 instruction to be replaced is shorter than the jump. To request a
2078 fast tracepoint, use the "ftrace" command, with syntax identical to
2079 the regular trace command.
2081 ** Disconnected tracing
2083 It is now possible to detach GDB from the target while it is running
2084 a trace experiment, then reconnect later to see how the experiment
2085 is going. In addition, a new variable disconnected-tracing lets you
2086 tell the target agent whether to continue running a trace if the
2087 connection is lost unexpectedly.
2091 GDB now has the ability to save the trace buffer into a file, and
2092 then use that file as a target, similarly to you can do with
2093 corefiles. You can select trace frames, print data that was
2094 collected in them, and use tstatus to display the state of the
2095 tracing run at the moment that it was saved. To create a trace
2096 file, use "tsave <filename>", and to use it, do "target tfile
2099 ** Circular trace buffer
2101 You can ask the target agent to handle the trace buffer as a
2102 circular buffer, discarding the oldest trace frames to make room for
2103 newer ones, by setting circular-trace-buffer to on. This feature may
2104 not be available for all target agents.
2109 The disassemble command, when invoked with two arguments, now requires
2110 the arguments to be comma-separated.
2113 The info variables command now displays variable definitions. Files
2114 which only declare a variable are not shown.
2117 The source command is now capable of sourcing Python scripts.
2118 This feature is dependent on the debugger being build with Python
2121 Related to this enhancement is also the introduction of a new command
2122 "set script-extension" (see below).
2124 * New commands (for set/show, see "New options" below)
2126 record save [<FILENAME>]
2127 Save a file (in core file format) containing the process record
2128 execution log for replay debugging at a later time.
2130 record restore <FILENAME>
2131 Restore the process record execution log that was saved at an
2132 earlier time, for replay debugging.
2134 add-inferior [-copies <N>] [-exec <FILENAME>]
2137 clone-inferior [-copies <N>] [ID]
2138 Make a new inferior ready to execute the same program another
2139 inferior has loaded.
2144 maint info program-spaces
2145 List the program spaces loaded into GDB.
2147 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2148 show remote interrupt-sequence
2149 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2150 as the sequence to the remote target in order to interrupt the execution.
2151 Ctrl-C is a default. Some system prefers BREAK which is high level of
2152 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2153 Magic SysRq g. It is BREAK signal and character 'g'.
2155 set remote interrupt-on-connect [on | off]
2156 show remote interrupt-on-connect
2157 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2158 remote target when gdb connects to it. This is needed when you debug
2161 set remotebreak [on | off]
2163 Deprecated. Use "set/show remote interrupt-sequence" instead.
2165 tvariable $NAME [ = EXP ]
2166 Create or modify a trace state variable.
2169 List trace state variables and their values.
2171 delete tvariable $NAME ...
2172 Delete one or more trace state variables.
2175 Evaluate the given expressions without collecting anything into the
2176 trace buffer. (Valid in tracepoint actions only.)
2178 ftrace FN / FILE:LINE / *ADDR
2179 Define a fast tracepoint at the given function, line, or address.
2181 * New expression syntax
2183 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2184 GDB now parses 0b101010 identically with 42.
2188 set follow-exec-mode new|same
2189 show follow-exec-mode
2190 Control whether GDB reuses the same inferior across an exec call or
2191 creates a new one. This is useful to be able to restart the old
2192 executable after the inferior having done an exec call.
2194 set default-collect EXPR, ...
2195 show default-collect
2196 Define a list of expressions to be collected at each tracepoint.
2197 This is a useful way to ensure essential items are not overlooked,
2198 such as registers or a critical global variable.
2200 set disconnected-tracing
2201 show disconnected-tracing
2202 If set to 1, the target is instructed to continue tracing if it
2203 loses its connection to GDB. If 0, the target is to stop tracing
2206 set circular-trace-buffer
2207 show circular-trace-buffer
2208 If set to on, the target is instructed to use a circular trace buffer
2209 and discard the oldest trace frames instead of stopping the trace due
2210 to a full trace buffer. If set to off, the trace stops when the buffer
2211 fills up. Some targets may not support this.
2213 set script-extension off|soft|strict
2214 show script-extension
2215 If set to "off", the debugger does not perform any script language
2216 recognition, and all sourced files are assumed to be GDB scripts.
2217 If set to "soft" (the default), files are sourced according to
2218 filename extension, falling back to GDB scripts if the first
2220 If set to "strict", files are sourced according to filename extension.
2222 set ada trust-PAD-over-XVS on|off
2223 show ada trust-PAD-over-XVS
2224 If off, activate a workaround against a bug in the debugging information
2225 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2226 the GCC sources for more information about the GNAT encoding and
2227 PAD types in particular). It is always safe to set this option to
2228 off, but this introduces a slight performance penalty. The default
2231 * Python API Improvements
2233 ** GDB provides the new class gdb.LazyString. This is useful in
2234 some pretty-printing cases. The new method gdb.Value.lazy_string
2235 provides a simple way to create objects of this type.
2237 ** The fields returned by gdb.Type.fields now have an
2238 `is_base_class' attribute.
2240 ** The new method gdb.Type.range returns the range of an array type.
2242 ** The new method gdb.parse_and_eval can be used to parse and
2243 evaluate an expression.
2245 * New remote packets
2248 Define a trace state variable.
2251 Get the current value of a trace state variable.
2254 Set desired tracing behavior upon disconnection.
2257 Set the trace buffer to be linear or circular.
2260 Get data about the tracepoints currently in use.
2264 Process record now works correctly with hardware watchpoints.
2266 Multiple bug fixes have been made to the mips-irix port, making it
2267 much more reliable. In particular:
2268 - Debugging threaded applications is now possible again. Previously,
2269 GDB would hang while starting the program, or while waiting for
2270 the program to stop at a breakpoint.
2271 - Attaching to a running process no longer hangs.
2272 - An error occurring while loading a core file has been fixed.
2273 - Changing the value of the PC register now works again. This fixes
2274 problems observed when using the "jump" command, or when calling
2275 a function from GDB, or even when assigning a new value to $pc.
2276 - With the "finish" and "return" commands, the return value for functions
2277 returning a small array is now correctly printed.
2278 - It is now possible to break on shared library code which gets executed
2279 during a shared library init phase (code executed while executing
2280 their .init section). Previously, the breakpoint would have no effect.
2281 - GDB is now able to backtrace through the signal handler for
2282 non-threaded programs.
2284 PIE (Position Independent Executable) programs debugging is now supported.
2285 This includes debugging execution of PIC (Position Independent Code) shared
2286 libraries although for that, it should be possible to run such libraries as an
2289 *** Changes in GDB 7.0
2291 * GDB now has an interface for JIT compilation. Applications that
2292 dynamically generate code can create symbol files in memory and register
2293 them with GDB. For users, the feature should work transparently, and
2294 for JIT developers, the interface is documented in the GDB manual in the
2295 "JIT Compilation Interface" chapter.
2297 * Tracepoints may now be conditional. The syntax is as for
2298 breakpoints; either an "if" clause appended to the "trace" command,
2299 or the "condition" command is available. GDB sends the condition to
2300 the target for evaluation using the same bytecode format as is used
2301 for tracepoint actions.
2303 * The disassemble command now supports: an optional /r modifier, print the
2304 raw instructions in hex as well as in symbolic form, and an optional /m
2305 modifier to print mixed source+assembly.
2307 * Process record and replay
2309 In a architecture environment that supports ``process record and
2310 replay'', ``process record and replay'' target can record a log of
2311 the process execution, and replay it with both forward and reverse
2314 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2315 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2316 set execution-direction {forward|reverse}, for targets that support
2319 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2320 feature is available with a native GDB running on kernel version
2323 * GDB now has support for multi-byte and wide character sets on the
2324 target. Strings whose character type is wchar_t, char16_t, or
2325 char32_t are now correctly printed. GDB supports wide- and unicode-
2326 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2327 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2328 `printf'. This feature requires iconv to work properly; if your
2329 system does not have a working iconv, GDB can use GNU libiconv. See
2330 the installation instructions for more information.
2332 * GDB now supports automatic retrieval of shared library files from
2333 remote targets. To use this feature, specify a system root that begins
2334 with the `remote:' prefix, either via the `set sysroot' command or via
2335 the `--with-sysroot' configure-time option.
2337 * "info sharedlibrary" now takes an optional regex of libraries to show,
2338 and it now reports if a shared library has no debugging information.
2340 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2341 now complete on file names.
2343 * When completing in expressions, gdb will attempt to limit
2344 completions to allowable structure or union fields, where appropriate.
2345 For instance, consider:
2347 # struct example { int f1; double f2; };
2348 # struct example variable;
2351 If the user types TAB at the end of this command line, the available
2352 completions will be "f1" and "f2".
2354 * Inlined functions are now supported. They show up in backtraces, and
2355 the "step", "next", and "finish" commands handle them automatically.
2357 * GDB now supports the token-splicing (##) and stringification (#)
2358 operators when expanding macros. It also supports variable-arity
2361 * GDB now supports inspecting extra signal information, exported by
2362 the new $_siginfo convenience variable. The feature is currently
2363 implemented on linux ARM, i386 and amd64.
2365 * GDB can now display the VFP floating point registers and NEON vector
2366 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2367 can provide these registers (requires Linux 2.6.30 or later). Remote
2368 and simulator targets may also provide them.
2370 * New remote packets
2373 Search memory for a sequence of bytes.
2376 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2377 operation over reliable transport links. Use of this packet is
2378 controlled by the `set remote noack-packet' command.
2381 Kill the process with the specified process ID. Use this in preference
2382 to `k' when multiprocess protocol extensions are supported.
2385 Obtains additional operating system information
2389 Read or write additional signal information.
2391 * Removed remote protocol undocumented extension
2393 An undocumented extension to the remote protocol's `S' stop reply
2394 packet that permited the stub to pass a process id was removed.
2395 Remote servers should use the `T' stop reply packet instead.
2397 * GDB now supports multiple function calling conventions according to the
2398 DWARF-2 DW_AT_calling_convention function attribute.
2400 * The SH target utilizes the aforementioned change to distinguish between gcc
2401 and Renesas calling convention. It also adds the new CLI commands
2402 `set/show sh calling-convention'.
2404 * GDB can now read compressed debug sections, as produced by GNU gold
2405 with the --compress-debug-sections=zlib flag.
2407 * 64-bit core files are now supported on AIX.
2409 * Thread switching is now supported on Tru64.
2411 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2412 which will be allocated using malloc later in program execution.
2414 * The qXfer:libraries:read remote procotol packet now allows passing a
2415 list of section offsets.
2417 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2418 conditions handling signals delivered during attach or thread creation
2419 have also been fixed.
2421 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2422 From the user's standpoint, all unqualified instances of True and False
2423 are treated as the standard definitions, regardless of context.
2425 * GDB now parses C++ symbol and type names more flexibly. For
2428 template<typename T> class C { };
2431 GDB will now correctly handle all of:
2433 ptype C<char const *>
2434 ptype C<char const*>
2435 ptype C<const char *>
2436 ptype C<const char*>
2438 * New features in the GDB remote stub, gdbserver
2440 - The "--wrapper" command-line argument tells gdbserver to use a
2441 wrapper program to launch programs for debugging.
2443 - On PowerPC and S/390 targets, it is now possible to use a single
2444 gdbserver executable to debug both 32-bit and 64-bit programs.
2445 (This requires gdbserver itself to be built as a 64-bit executable.)
2447 - gdbserver uses the new noack protocol mode for TCP connections to
2448 reduce communications latency, if also supported and enabled in GDB.
2450 - Support for the sparc64-linux-gnu target is now included in
2453 - The amd64-linux build of gdbserver now supports debugging both
2454 32-bit and 64-bit programs.
2456 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2457 now support hardware watchpoints, and will use them automatically
2462 GDB now has support for scripting using Python. Whether this is
2463 available is determined at configure time.
2465 New GDB commands can now be written in Python.
2467 * Ada tasking support
2469 Ada tasks can now be inspected in GDB. The following commands have
2473 Print the list of Ada tasks.
2475 Print detailed information about task number N.
2477 Print the task number of the current task.
2479 Switch the context of debugging to task number N.
2481 * Support for user-defined prefixed commands. The "define" command can
2482 add new commands to existing prefixes, e.g. "target".
2484 * Multi-inferior, multi-process debugging.
2486 GDB now has generalized support for multi-inferior debugging. See
2487 "Debugging Multiple Inferiors" in the manual for more information.
2488 Although availability still depends on target support, the command
2489 set is more uniform now. The GNU/Linux specific multi-forks support
2490 has been migrated to this new framework. This implied some user
2491 visible changes; see "New commands" and also "Removed commands"
2494 * Target descriptions can now describe the target OS ABI. See the
2495 "Target Description Format" section in the user manual for more
2498 * Target descriptions can now describe "compatible" architectures
2499 to indicate that the target can execute applications for a different
2500 architecture in addition to those for the main target architecture.
2501 See the "Target Description Format" section in the user manual for
2504 * Multi-architecture debugging.
2506 GDB now includes general supports for debugging applications on
2507 hybrid systems that use more than one single processor architecture
2508 at the same time. Each such hybrid architecture still requires
2509 specific support to be added. The only hybrid architecture supported
2510 in this version of GDB is the Cell Broadband Engine.
2512 * GDB now supports integrated debugging of Cell/B.E. applications that
2513 use both the PPU and SPU architectures. To enable support for hybrid
2514 Cell/B.E. debugging, you need to configure GDB to support both the
2515 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2516 --enable-targets configure option.
2518 * Non-stop mode debugging.
2520 For some targets, GDB now supports an optional mode of operation in
2521 which you can examine stopped threads while other threads continue
2522 to execute freely. This is referred to as non-stop mode, with the
2523 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2524 section in the user manual for more information.
2526 To be able to support remote non-stop debugging, a remote stub needs
2527 to implement the non-stop mode remote protocol extensions, as
2528 described in the "Remote Non-Stop" section of the user manual. The
2529 GDB remote stub, gdbserver, has been adjusted to support these
2530 extensions on linux targets.
2532 * New commands (for set/show, see "New options" below)
2534 catch syscall [NAME(S) | NUMBER(S)]
2535 Catch system calls. Arguments, which should be names of system
2536 calls or their numbers, mean catch only those syscalls. Without
2537 arguments, every syscall will be caught. When the inferior issues
2538 any of the specified syscalls, GDB will stop and announce the system
2539 call, both when it is called and when its call returns. This
2540 feature is currently available with a native GDB running on the
2541 Linux Kernel, under the following architectures: x86, x86_64,
2542 PowerPC and PowerPC64.
2544 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2546 Search memory for a sequence of bytes.
2548 maint set python print-stack
2549 maint show python print-stack
2550 Show a stack trace when an error is encountered in a Python script.
2553 Invoke CODE by passing it to the Python interpreter.
2558 These allow macros to be defined, undefined, and listed
2562 Show operating system information about processes.
2565 List the inferiors currently under GDB's control.
2568 Switch focus to inferior number NUM.
2571 Detach from inferior number NUM.
2574 Kill inferior number NUM.
2578 set spu stop-on-load
2579 show spu stop-on-load
2580 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2582 set spu auto-flush-cache
2583 show spu auto-flush-cache
2584 Control whether to automatically flush the software-managed cache
2585 during Cell/B.E. debugging.
2587 set sh calling-convention
2588 show sh calling-convention
2589 Control the calling convention used when calling SH target functions.
2592 show debug timestamp
2593 Control display of timestamps with GDB debugging output.
2595 set disassemble-next-line
2596 show disassemble-next-line
2597 Control display of disassembled source lines or instructions when
2600 set remote noack-packet
2601 show remote noack-packet
2602 Set/show the use of remote protocol QStartNoAckMode packet. See above
2603 under "New remote packets."
2605 set remote query-attached-packet
2606 show remote query-attached-packet
2607 Control use of remote protocol `qAttached' (query-attached) packet.
2609 set remote read-siginfo-object
2610 show remote read-siginfo-object
2611 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2614 set remote write-siginfo-object
2615 show remote write-siginfo-object
2616 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2619 set remote reverse-continue
2620 show remote reverse-continue
2621 Control use of remote protocol 'bc' (reverse-continue) packet.
2623 set remote reverse-step
2624 show remote reverse-step
2625 Control use of remote protocol 'bs' (reverse-step) packet.
2627 set displaced-stepping
2628 show displaced-stepping
2629 Control displaced stepping mode. Displaced stepping is a way to
2630 single-step over breakpoints without removing them from the debuggee.
2631 Also known as "out-of-line single-stepping".
2634 show debug displaced
2635 Control display of debugging info for displaced stepping.
2637 maint set internal-error
2638 maint show internal-error
2639 Control what GDB does when an internal error is detected.
2641 maint set internal-warning
2642 maint show internal-warning
2643 Control what GDB does when an internal warning is detected.
2648 Use a wrapper program to launch programs for debugging.
2650 set multiple-symbols (all|ask|cancel)
2651 show multiple-symbols
2652 The value of this variable can be changed to adjust the debugger behavior
2653 when an expression or a breakpoint location contains an ambiguous symbol
2654 name (an overloaded function name, for instance).
2656 set breakpoint always-inserted
2657 show breakpoint always-inserted
2658 Keep breakpoints always inserted in the target, as opposed to inserting
2659 them when resuming the target, and removing them when the target stops.
2660 This option can improve debugger performance on slow remote targets.
2662 set arm fallback-mode (arm|thumb|auto)
2663 show arm fallback-mode
2664 set arm force-mode (arm|thumb|auto)
2666 These commands control how ARM GDB determines whether instructions
2667 are ARM or Thumb. The default for both settings is auto, which uses
2668 the current CPSR value for instructions without symbols; previous
2669 versions of GDB behaved as if "set arm fallback-mode arm".
2671 set disable-randomization
2672 show disable-randomization
2673 Standalone programs run with the virtual address space randomization enabled
2674 by default on some platforms. This option keeps the addresses stable across
2675 multiple debugging sessions.
2679 Control whether other threads are stopped or not when some thread hits
2684 Requests that asynchronous execution is enabled in the target, if available.
2685 In this case, it's possible to resume target in the background, and interact
2686 with GDB while the target is running. "show target-async" displays the
2687 current state of asynchronous execution of the target.
2689 set target-wide-charset
2690 show target-wide-charset
2691 The target-wide-charset is the name of the character set that GDB
2692 uses when printing characters whose type is wchar_t.
2694 set tcp auto-retry (on|off)
2696 set tcp connect-timeout
2697 show tcp connect-timeout
2698 These commands allow GDB to retry failed TCP connections to a remote stub
2699 with a specified timeout period; this is useful if the stub is launched
2700 in parallel with GDB but may not be ready to accept connections immediately.
2702 set libthread-db-search-path
2703 show libthread-db-search-path
2704 Control list of directories which GDB will search for appropriate
2707 set schedule-multiple (on|off)
2708 show schedule-multiple
2709 Allow GDB to resume all threads of all processes or only threads of
2710 the current process.
2714 Use more aggressive caching for accesses to the stack. This improves
2715 performance of remote debugging (particularly backtraces) without
2716 affecting correctness.
2718 set interactive-mode (on|off|auto)
2719 show interactive-mode
2720 Control whether GDB runs in interactive mode (on) or not (off).
2721 When in interactive mode, GDB waits for the user to answer all
2722 queries. Otherwise, GDB does not wait and assumes the default
2723 answer. When set to auto (the default), GDB determines which
2724 mode to use based on the stdin settings.
2729 For program forks, this is replaced by the new more generic `info
2730 inferiors' command. To list checkpoints, you can still use the
2731 `info checkpoints' command, which was an alias for the `info forks'
2735 Replaced by the new `inferior' command. To switch between
2736 checkpoints, you can still use the `restart' command, which was an
2737 alias for the `fork' command.
2740 This is removed, since some targets don't have a notion of
2741 processes. To switch between processes, you can still use the
2742 `inferior' command using GDB's own inferior number.
2745 For program forks, this is replaced by the new more generic `kill
2746 inferior' command. To delete a checkpoint, you can still use the
2747 `delete checkpoint' command, which was an alias for the `delete
2751 For program forks, this is replaced by the new more generic `detach
2752 inferior' command. To detach a checkpoint, you can still use the
2753 `detach checkpoint' command, which was an alias for the `detach
2756 * New native configurations
2758 x86/x86_64 Darwin i[34567]86-*-darwin*
2760 x86_64 MinGW x86_64-*-mingw*
2764 Lattice Mico32 lm32-*
2765 x86 DICOS i[34567]86-*-dicos*
2766 x86_64 DICOS x86_64-*-dicos*
2769 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2770 (mingw32ce) debugging.
2776 These commands were actually not implemented on any target.
2778 *** Changes in GDB 6.8
2780 * New native configurations
2782 NetBSD/hppa hppa*-*netbsd*
2783 Xtensa GNU/Linux xtensa*-*-linux*
2787 NetBSD/hppa hppa*-*-netbsd*
2788 Xtensa GNU/Lunux xtensa*-*-linux*
2790 * Change in command line behavior -- corefiles vs. process ids.
2792 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2793 attaching to process NUMBER fails, GDB no longer attempts to open a
2794 core file named NUMBER. Attaching to a program using the -c option
2795 is no longer supported. Instead, use the '-p' or '--pid' options.
2797 * GDB can now be built as a native debugger for debugging Windows x86
2798 (mingw32) Portable Executable (PE) programs.
2800 * Pending breakpoints no longer change their number when their address
2803 * GDB now supports breakpoints with multiple locations,
2804 including breakpoints on C++ constructors, inside C++ templates,
2805 and in inlined functions.
2807 * GDB's ability to debug optimized code has been improved. GDB more
2808 accurately identifies function bodies and lexical blocks that occupy
2809 more than one contiguous range of addresses.
2811 * Target descriptions can now describe registers for PowerPC.
2813 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2814 registers on PowerPC targets.
2816 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2817 targets even when the libthread_db library is not available.
2819 * The GDB remote stub, gdbserver, now supports the new file transfer
2820 commands (remote put, remote get, and remote delete).
2822 * The GDB remote stub, gdbserver, now supports run and attach in
2823 extended-remote mode.
2825 * hppa*64*-*-hpux11* target broken
2826 The debugger is unable to start a program and fails with the following
2827 error: "Error trying to get information about dynamic linker".
2828 The gdb-6.7 release is also affected.
2830 * GDB now supports the --enable-targets= configure option to allow
2831 building a single GDB executable that supports multiple remote
2832 target architectures.
2834 * GDB now supports debugging C and C++ programs which use the
2835 Decimal Floating Point extension. In addition, the PowerPC target
2836 now has a set of pseudo-registers to inspect decimal float values
2837 stored in two consecutive float registers.
2839 * The -break-insert MI command can optionally create pending
2842 * Improved support for debugging Ada
2843 Many improvements to the Ada language support have been made. These
2845 - Better support for Ada2005 interface types
2846 - Improved handling of arrays and slices in general
2847 - Better support for Taft-amendment types
2848 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2850 - Improved command completion in Ada
2853 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2858 set print frame-arguments (all|scalars|none)
2859 show print frame-arguments
2860 The value of this variable can be changed to control which argument
2861 values should be printed by the debugger when displaying a frame.
2866 Transfer files to and from a remote target, and delete remote files.
2873 Transfer files to and from a remote target, and delete remote files.
2875 * New remote packets
2882 Open, close, read, write, and delete files on the remote system.
2885 Attach to an existing process on the remote system, in extended-remote
2889 Run a new process on the remote system, in extended-remote mode.
2891 *** Changes in GDB 6.7
2893 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2894 bfd, libiberty and opcodes, as revealed by static analysis donated by
2895 Coverity, Inc. (http://scan.coverity.com).
2897 * When looking up multiply-defined global symbols, GDB will now prefer the
2898 symbol definition in the current shared library if it was built using the
2899 -Bsymbolic linker option.
2901 * When the Text User Interface (TUI) is not configured, GDB will now
2902 recognize the -tui command-line option and print a message that the TUI
2905 * The GDB remote stub, gdbserver, now has lower overhead for high
2906 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2908 * GDB for MIPS targets now autodetects whether a remote target provides
2909 32-bit or 64-bit register values.
2911 * Support for C++ member pointers has been improved.
2913 * GDB now understands XML target descriptions, which specify the
2914 target's overall architecture. GDB can read a description from
2915 a local file or over the remote serial protocol.
2917 * Vectors of single-byte data use a new integer type which is not
2918 automatically displayed as character or string data.
2920 * The /s format now works with the print command. It displays
2921 arrays of single-byte integers and pointers to single-byte integers
2924 * Target descriptions can now describe target-specific registers,
2925 for architectures which have implemented the support (currently
2926 only ARM, M68K, and MIPS).
2928 * GDB and the GDB remote stub, gdbserver, now support the XScale
2931 * The GDB remote stub, gdbserver, has been updated to support
2932 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2933 has been rewritten to use the standard GDB remote protocol.
2935 * GDB can now step into C++ functions which are called through thunks.
2937 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2939 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2940 layout. It also supports a TextSeg= and DataSeg= response when only
2941 segment base addresses (rather than offsets) are available.
2943 * The /i format now outputs any trailing branch delay slot instructions
2944 immediately following the last instruction within the count specified.
2946 * The GDB remote protocol "T" stop reply packet now supports a
2947 "library" response. Combined with the new "qXfer:libraries:read"
2948 packet, this response allows GDB to debug shared libraries on targets
2949 where the operating system manages the list of loaded libraries (e.g.
2950 Windows and SymbianOS).
2952 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2953 (DLLs) on Windows and Windows CE targets.
2955 * GDB now supports a faster verification that a .debug file matches its binary
2956 according to its build-id signature, if the signature is present.
2962 Enable or disable hardware flow control (RTS/CTS) on the serial port
2963 when debugging using remote targets.
2965 set mem inaccessible-by-default
2966 show mem inaccessible-by-default
2967 If the target supplies a memory map, for instance via the remote
2968 protocol's "qXfer:memory-map:read" packet, setting this variable
2969 prevents GDB from accessing memory outside the memory map. This
2970 is useful for targets with memory mapped registers or which react
2971 badly to accesses of unmapped address space.
2973 set breakpoint auto-hw
2974 show breakpoint auto-hw
2975 If the target supplies a memory map, for instance via the remote
2976 protocol's "qXfer:memory-map:read" packet, setting this variable
2977 lets GDB use hardware breakpoints automatically for memory regions
2978 where it can not use software breakpoints. This covers both the
2979 "break" command and internal breakpoints used for other commands
2980 including "next" and "finish".
2983 catch exception unhandled
2984 Stop the program execution when Ada exceptions are raised.
2987 Stop the program execution when an Ada assertion failed.
2991 Set an alternate system root for target files. This is a more
2992 general version of "set solib-absolute-prefix", which is now
2993 an alias to "set sysroot".
2996 Provide extended SPU facility status information. This set of
2997 commands is available only when debugging the Cell/B.E. SPU
3000 * New native configurations
3002 OpenBSD/sh sh*-*openbsd*
3005 unset tdesc filename
3007 Use the specified local file as an XML target description, and do
3008 not query the target for its built-in description.
3012 OpenBSD/sh sh*-*-openbsd*
3013 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3014 Toshiba Media Processor mep-elf
3016 * New remote packets
3019 Ignore the specified signals; pass them directly to the debugged program
3020 without stopping other threads or reporting them to GDB.
3022 qXfer:features:read:
3023 Read an XML target description from the target, which describes its
3028 Read or write contents of an spufs file on the target system. These
3029 packets are available only on the Cell/B.E. SPU architecture.
3031 qXfer:libraries:read:
3032 Report the loaded shared libraries. Combined with new "T" packet
3033 response, this packet allows GDB to debug shared libraries on
3034 targets where the operating system manages the list of loaded
3035 libraries (e.g. Windows and SymbianOS).
3039 Support for these obsolete configurations has been removed.
3047 i[34567]86-*-lynxos*
3048 i[34567]86-*-netware*
3049 i[34567]86-*-sco3.2v5*
3050 i[34567]86-*-sco3.2v4*
3052 i[34567]86-*-sysv4.2*
3055 i[34567]86-*-unixware2*
3056 i[34567]86-*-unixware*
3065 * Other removed features
3072 Various m68k-only ROM monitors.
3079 Various Renesas ROM monitors and debugging interfaces for SH and
3084 Support for a Macraigor serial interface to on-chip debugging.
3085 GDB does not directly support the newer parallel or USB
3090 A debug information format. The predecessor to DWARF 2 and
3091 DWARF 3, which are still supported.
3093 Support for the HP aCC compiler on HP-UX/PA-RISC
3095 SOM-encapsulated symbolic debugging information, automatic
3096 invocation of pxdb, and the aCC custom C++ ABI. This does not
3097 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3098 with aCC can still be debugged on an assembly level.
3100 MIPS ".pdr" sections
3102 A MIPS-specific format used to describe stack frame layout
3103 in debugging information.
3107 GDB could work with an older version of Guile to debug
3108 the interpreter and Scheme programs running in it.
3110 set mips stack-arg-size
3111 set mips saved-gpreg-size
3113 Use "set mips abi" to control parameter passing for MIPS.
3115 *** Changes in GDB 6.6
3120 Cell Broadband Engine SPU spu-elf
3122 * GDB can now be configured as a cross-debugger targeting native Windows
3123 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3124 running on a Windows system over TCP/IP to debug Windows programs.
3126 * The GDB remote stub, gdbserver, has been updated to support Windows and
3127 Cygwin debugging. Both single-threaded and multi-threaded programs are
3130 * The "set trust-readonly-sections" command works again. This command was
3131 broken in GDB 6.3, 6.4, and 6.5.
3133 * The "load" command now supports writing to flash memory, if the remote
3134 stub provides the required support.
3136 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3137 longer requires symbolic debug information (e.g. DWARF-2).
3142 unset substitute-path
3143 show substitute-path
3144 Manage a list of substitution rules that GDB uses to rewrite the name
3145 of the directories where the sources are located. This can be useful
3146 for instance when the sources were moved to a different location
3147 between compilation and debugging.
3151 Print each CLI command as it is executed. Each command is prefixed with
3152 a number of `+' symbols representing the nesting depth.
3153 The source command now has a `-v' option to enable the same feature.
3157 The ARM Demon monitor support (RDP protocol, "target rdp").
3159 Kernel Object Display, an embedded debugging feature which only worked with
3160 an obsolete version of Cisco IOS.
3162 The 'set download-write-size' and 'show download-write-size' commands.
3164 * New remote packets
3167 Tell a stub about GDB client features, and request remote target features.
3168 The first feature implemented is PacketSize, which allows the target to
3169 specify the size of packets it can handle - to minimize the number of
3170 packets required and improve performance when connected to a remote
3174 Fetch an OS auxilliary vector from the remote stub. This packet is a
3175 more efficient replacement for qPart:auxv:read.
3177 qXfer:memory-map:read:
3178 Fetch a memory map from the remote stub, including information about
3179 RAM, ROM, and flash memory devices.
3184 Erase and program a flash memory device.
3186 * Removed remote packets
3189 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3190 used it, and only gdbserver implemented it.
3192 *** Changes in GDB 6.5
3196 Renesas M32C/M16C m32c-elf
3198 Morpho Technologies ms1 ms1-elf
3202 init-if-undefined Initialize a convenience variable, but
3203 only if it doesn't already have a value.
3205 The following commands are presently only implemented for native GNU/Linux:
3207 checkpoint Save a snapshot of the program state.
3209 restart <n> Return the program state to a
3210 previously saved state.
3212 info checkpoints List currently saved checkpoints.
3214 delete-checkpoint <n> Delete a previously saved checkpoint.
3216 set|show detach-on-fork Tell gdb whether to detach from a newly
3217 forked process, or to keep debugging it.
3219 info forks List forks of the user program that
3220 are available to be debugged.
3222 fork <n> Switch to debugging one of several
3223 forks of the user program that are
3224 available to be debugged.
3226 delete-fork <n> Delete a fork from the list of forks
3227 that are available to be debugged (and
3228 kill the forked process).
3230 detach-fork <n> Delete a fork from the list of forks
3231 that are available to be debugged (and
3232 allow the process to continue).
3236 Morpho Technologies ms2 ms1-elf
3238 * Improved Windows host support
3240 GDB now builds as a cross debugger hosted on i686-mingw32, including
3241 native console support, and remote communications using either
3242 network sockets or serial ports.
3244 * Improved Modula-2 language support
3246 GDB can now print most types in the Modula-2 syntax. This includes:
3247 basic types, set types, record types, enumerated types, range types,
3248 pointer types and ARRAY types. Procedure var parameters are correctly
3249 printed and hexadecimal addresses and character constants are also
3250 written in the Modula-2 syntax. Best results can be obtained by using
3251 GNU Modula-2 together with the -gdwarf-2 command line option.
3255 The ARM rdi-share module.
3257 The Netware NLM debug server.
3259 *** Changes in GDB 6.4
3261 * New native configurations
3263 OpenBSD/arm arm*-*-openbsd*
3264 OpenBSD/mips64 mips64-*-openbsd*
3268 Morpho Technologies ms1 ms1-elf
3270 * New command line options
3272 --batch-silent As for --batch, but totally silent.
3273 --return-child-result The debugger will exist with the same value
3274 the child (debugged) program exited with.
3275 --eval-command COMMAND, -ex COMMAND
3276 Execute a single GDB CLI command. This may be
3277 specified multiple times and in conjunction
3278 with the --command (-x) option.
3280 * Deprecated commands removed
3282 The following commands, that were deprecated in 2000, have been
3286 set|show arm disassembly-flavor set|show arm disassembler
3287 othernames set arm disassembler
3288 set|show remotedebug set|show debug remote
3289 set|show archdebug set|show debug arch
3290 set|show eventdebug set|show debug event
3293 * New BSD user-level threads support
3295 It is now possible to debug programs using the user-level threads
3296 library on OpenBSD and FreeBSD. Currently supported (target)
3299 FreeBSD/amd64 x86_64-*-freebsd*
3300 FreeBSD/i386 i386-*-freebsd*
3301 OpenBSD/i386 i386-*-openbsd*
3303 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3304 are not yet supported.
3306 * New support for Matsushita MN10300 w/sim added
3307 (Work in progress). mn10300-elf.
3309 * REMOVED configurations and files
3311 VxWorks and the XDR protocol *-*-vxworks
3312 Motorola MCORE mcore-*-*
3313 National Semiconductor NS32000 ns32k-*-*
3315 * New "set print array-indexes" command
3317 After turning this setting "on", GDB prints the index of each element
3318 when displaying arrays. The default is "off" to preserve the previous
3321 * VAX floating point support
3323 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3325 * User-defined command support
3327 In addition to using $arg0..$arg9 for argument passing, it is now possible
3328 to use $argc to determine now many arguments have been passed. See the
3329 section on user-defined commands in the user manual for more information.
3331 *** Changes in GDB 6.3:
3333 * New command line option
3335 GDB now accepts -l followed by a number to set the timeout for remote
3338 * GDB works with GCC -feliminate-dwarf2-dups
3340 GDB now supports a more compact representation of DWARF-2 debug
3341 information using DW_FORM_ref_addr references. These are produced
3342 by GCC with the option -feliminate-dwarf2-dups and also by some
3343 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3344 to use -feliminate-dwarf2-dups.
3346 * Internationalization
3348 When supported by the host system, GDB will be built with
3349 internationalization (libintl). The task of marking up the sources is
3350 continued, we're looking forward to our first translation.
3354 Initial support for debugging programs compiled with the GNAT
3355 implementation of the Ada programming language has been integrated
3356 into GDB. In this release, support is limited to expression evaluation.
3358 * New native configurations
3360 GNU/Linux/m32r m32r-*-linux-gnu
3364 GDB's remote protocol now includes support for the 'p' packet. This
3365 packet is used to fetch individual registers from a remote inferior.
3367 * END-OF-LIFE registers[] compatibility module
3369 GDB's internal register infrastructure has been completely rewritten.
3370 The new infrastructure making possible the implementation of key new
3371 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3374 GDB 6.3 will be the last release to include the the registers[]
3375 compatibility module that allowed out-of-date configurations to
3376 continue to work. This change directly impacts the following
3386 powerpc bdm protocol
3388 Unless there is activity to revive these configurations, they will be
3389 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3391 * OBSOLETE configurations and files
3393 Configurations that have been declared obsolete in this release have
3394 been commented out. Unless there is activity to revive these
3395 configurations, the next release of GDB will have their sources
3396 permanently REMOVED.
3405 *** Changes in GDB 6.2.1:
3407 * MIPS `break main; run' gave an heuristic-fence-post warning
3409 When attempting to run even a simple program, a warning about
3410 heuristic-fence-post being hit would be reported. This problem has
3413 * MIPS IRIX 'long double' crashed GDB
3415 When examining a long double variable, GDB would get a segmentation
3416 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3417 IRIX long double values).
3421 A bug in the VAX stack code was causing problems with the "next"
3422 command. This problem has been fixed.
3424 *** Changes in GDB 6.2:
3426 * Fix for ``many threads''
3428 On GNU/Linux systems that use the NPTL threads library, a program
3429 rapidly creating and deleting threads would confuse GDB leading to the
3432 ptrace: No such process.
3433 thread_db_get_info: cannot get thread info: generic error
3435 This problem has been fixed.
3437 * "-async" and "-noasync" options removed.
3439 Support for the broken "-noasync" option has been removed (it caused
3442 * New ``start'' command.
3444 This command runs the program until the begining of the main procedure.
3446 * New BSD Kernel Data Access Library (libkvm) interface
3448 Using ``target kvm'' it is now possible to debug kernel core dumps and
3449 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3450 platforms. Currently supported (native-only) configurations are:
3452 FreeBSD/amd64 x86_64-*-freebsd*
3453 FreeBSD/i386 i?86-*-freebsd*
3454 NetBSD/i386 i?86-*-netbsd*
3455 NetBSD/m68k m68*-*-netbsd*
3456 NetBSD/sparc sparc-*-netbsd*
3457 OpenBSD/amd64 x86_64-*-openbsd*
3458 OpenBSD/i386 i?86-*-openbsd*
3459 OpenBSD/m68k m68*-openbsd*
3460 OpenBSD/sparc sparc-*-openbsd*
3462 * Signal trampoline code overhauled
3464 Many generic problems with GDB's signal handling code have been fixed.
3465 These include: backtraces through non-contiguous stacks; recognition
3466 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3467 call; backtrace through a signal trampoline; step into and out of
3468 signal handlers; and single-stepping in the signal trampoline.
3470 Please note that kernel bugs are a limiting factor here. These
3471 features have been shown to work on an s390 GNU/Linux system that
3472 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3474 * Cygwin support for DWARF 2 added.
3476 * New native configurations
3478 GNU/Linux/hppa hppa*-*-linux*
3479 OpenBSD/hppa hppa*-*-openbsd*
3480 OpenBSD/m68k m68*-*-openbsd*
3481 OpenBSD/m88k m88*-*-openbsd*
3482 OpenBSD/powerpc powerpc-*-openbsd*
3483 NetBSD/vax vax-*-netbsd*
3484 OpenBSD/vax vax-*-openbsd*
3486 * END-OF-LIFE frame compatibility module
3488 GDB's internal frame infrastructure has been completely rewritten.
3489 The new infrastructure making it possible to support key new features
3490 including DWARF 2 Call Frame Information. To aid in the task of
3491 migrating old configurations to this new infrastructure, a
3492 compatibility module, that allowed old configurations to continue to
3493 work, was also included.
3495 GDB 6.2 will be the last release to include this frame compatibility
3496 module. This change directly impacts the following configurations:
3506 Unless there is activity to revive these configurations, they will be
3507 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3509 * REMOVED configurations and files
3511 Sun 3, running SunOS 3 m68*-*-sunos3*
3512 Sun 3, running SunOS 4 m68*-*-sunos4*
3513 Sun 2, running SunOS 3 m68000-*-sunos3*
3514 Sun 2, running SunOS 4 m68000-*-sunos4*
3515 Motorola 680x0 running LynxOS m68*-*-lynxos*
3516 AT&T 3b1/Unix pc m68*-att-*
3517 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3518 decstation mips-dec-* mips-little-*
3519 riscos mips-*-riscos* mips-*-sysv*
3520 sonymips mips-sony-*
3521 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3523 *** Changes in GDB 6.1.1:
3525 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3527 The TUI (Text-mode User Interface) is now built as part of a default
3528 GDB configuration. It is enabled by either selecting the TUI with the
3529 command line option "-i=tui" or by running the separate "gdbtui"
3530 program. For more information on the TUI, see the manual "Debugging
3533 * Pending breakpoint support (also included in GDB 6.1)
3535 Support has been added to allow you to specify breakpoints in shared
3536 libraries that have not yet been loaded. If a breakpoint location
3537 cannot be found, and the "breakpoint pending" option is set to auto,
3538 GDB queries you if you wish to make the breakpoint pending on a future
3539 shared-library load. If and when GDB resolves the breakpoint symbol,
3540 the pending breakpoint is removed as one or more regular breakpoints
3543 Pending breakpoints are very useful for GCJ Java debugging.
3545 * Fixed ISO-C build problems
3547 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3548 non ISO-C code that stopped them being built using a more strict ISO-C
3549 compiler (e.g., IBM's C compiler).
3551 * Fixed build problem on IRIX 5
3553 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3554 wasn't able to compile compile on an IRIX 5 system.
3556 * Added execute permission to gdb/gdbserver/configure
3558 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3559 permission. This bug would cause configure to fail on a number of
3560 systems (Solaris, IRIX). Ref: server/519.
3562 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3564 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3565 has been updated to use constant array sizes.
3567 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3569 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3570 its generated DWARF Call Frame Info. This encoding was causing GDB to
3571 panic, that panic has been fixed. Ref: gdb/1628.
3573 * Fixed a problem when examining parameters in shared library code.
3575 When examining parameters in optimized shared library code generated
3576 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3577 not available''. GDB now correctly displays the variable's value.
3579 *** Changes in GDB 6.1:
3581 * Removed --with-mmalloc
3583 Support for the mmalloc memory manager has been removed, as it
3584 conflicted with the internal gdb byte cache.
3586 * Changes in AMD64 configurations
3588 The AMD64 target now includes the %cs and %ss registers. As a result
3589 the AMD64 remote protocol has changed; this affects the floating-point
3590 and SSE registers. If you rely on those registers for your debugging,
3591 you should upgrade gdbserver on the remote side.
3593 * Revised SPARC target
3595 The SPARC target has been completely revised, incorporating the
3596 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3597 support for LynxOS and SunOS 4 has been dropped. Calling functions
3598 from within GDB on operating systems with a non-executable stack
3599 (Solaris, OpenBSD) now works.
3603 GDB has a new C++ demangler which does a better job on the mangled
3604 names generated by current versions of g++. It also runs faster, so
3605 with this and other changes gdb should now start faster on large C++
3608 * DWARF 2 Location Expressions
3610 GDB support for location expressions has been extended to support function
3611 arguments and frame bases. Older versions of GDB could crash when they
3614 * C++ nested types and namespaces
3616 GDB's support for nested types and namespaces in C++ has been
3617 improved, especially if you use the DWARF 2 debugging format. (This
3618 is the default for recent versions of GCC on most platforms.)
3619 Specifically, if you have a class "Inner" defined within a class or
3620 namespace "Outer", then GDB realizes that the class's name is
3621 "Outer::Inner", not simply "Inner". This should greatly reduce the
3622 frequency of complaints about not finding RTTI symbols. In addition,
3623 if you are stopped at inside of a function defined within a namespace,
3624 GDB modifies its name lookup accordingly.
3626 * New native configurations
3628 NetBSD/amd64 x86_64-*-netbsd*
3629 OpenBSD/amd64 x86_64-*-openbsd*
3630 OpenBSD/alpha alpha*-*-openbsd*
3631 OpenBSD/sparc sparc-*-openbsd*
3632 OpenBSD/sparc64 sparc64-*-openbsd*
3634 * New debugging protocols
3636 M32R with SDI protocol m32r-*-elf*
3638 * "set prompt-escape-char" command deleted.
3640 The command "set prompt-escape-char" has been deleted. This command,
3641 and its very obscure effet on GDB's prompt, was never documented,
3642 tested, nor mentioned in the NEWS file.
3644 * OBSOLETE configurations and files
3646 Configurations that have been declared obsolete in this release have
3647 been commented out. Unless there is activity to revive these
3648 configurations, the next release of GDB will have their sources
3649 permanently REMOVED.
3651 Sun 3, running SunOS 3 m68*-*-sunos3*
3652 Sun 3, running SunOS 4 m68*-*-sunos4*
3653 Sun 2, running SunOS 3 m68000-*-sunos3*
3654 Sun 2, running SunOS 4 m68000-*-sunos4*
3655 Motorola 680x0 running LynxOS m68*-*-lynxos*
3656 AT&T 3b1/Unix pc m68*-att-*
3657 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3658 decstation mips-dec-* mips-little-*
3659 riscos mips-*-riscos* mips-*-sysv*
3660 sonymips mips-sony-*
3661 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3663 * REMOVED configurations and files
3665 SGI Irix-4.x mips-sgi-irix4 or iris4
3666 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3667 Z8000 simulator z8k-zilog-none or z8ksim
3668 Matsushita MN10200 w/simulator mn10200-*-*
3669 H8/500 simulator h8500-hitachi-hms or h8500hms
3670 HP/PA running BSD hppa*-*-bsd*
3671 HP/PA running OSF/1 hppa*-*-osf*
3672 HP/PA Pro target hppa*-*-pro*
3673 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3674 386BSD i[3456]86-*-bsd*
3675 Sequent family i[3456]86-sequent-sysv4*
3676 i[3456]86-sequent-sysv*
3677 i[3456]86-sequent-bsd*
3678 SPARC running LynxOS sparc-*-lynxos*
3679 SPARC running SunOS 4 sparc-*-sunos4*
3680 Tsqware Sparclet sparclet-*-*
3681 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3683 *** Changes in GDB 6.0:
3687 Support for debugging the Objective-C programming language has been
3688 integrated into GDB.
3690 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3692 DWARF 2's Call Frame Information makes available compiler generated
3693 information that more exactly describes the program's run-time stack.
3694 By using this information, GDB is able to provide more robust stack
3697 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3698 have been updated to use a new backtrace mechanism which includes
3699 DWARF 2 CFI support.
3703 GDB's remote protocol has been extended to include support for hosted
3704 file I/O (where the remote target uses GDB's file system). See GDB's
3705 remote protocol documentation for details.
3707 * All targets using the new architecture framework.
3709 All of GDB's targets have been updated to use the new internal
3710 architecture framework. The way is now open for future GDB releases
3711 to include cross-architecture native debugging support (i386 on amd64,
3714 * GNU/Linux's Thread Local Storage (TLS)
3716 GDB now includes support for for the GNU/Linux implementation of
3717 per-thread variables.
3719 * GNU/Linux's Native POSIX Thread Library (NPTL)
3721 GDB's thread code has been updated to work with either the new
3722 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3724 * Separate debug info.
3726 GDB, in conjunction with BINUTILS, now supports a mechanism for
3727 automatically loading debug information from a separate file. Instead
3728 of shipping full debug and non-debug versions of system libraries,
3729 system integrators can now instead ship just the stripped libraries
3730 and optional debug files.
3732 * DWARF 2 Location Expressions
3734 DWARF 2 Location Expressions allow the compiler to more completely
3735 describe the location of variables (even in optimized code) to the
3738 GDB now includes preliminary support for location expressions (support
3739 for DW_OP_piece is still missing).
3743 A number of long standing bugs that caused GDB to die while starting a
3744 Java application have been fixed. GDB's Java support is now
3745 considered "useable".
3747 * GNU/Linux support for fork, vfork, and exec.
3749 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3750 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3753 * GDB supports logging output to a file
3755 There are two new commands, "set logging" and "show logging", which can be
3756 used to capture GDB's output to a file.
3758 * The meaning of "detach" has changed for gdbserver
3760 The "detach" command will now resume the application, as documented. To
3761 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3764 * d10v, m68hc11 `regs' command deprecated
3766 The `info registers' command has been updated so that it displays the
3767 registers using a format identical to the old `regs' command.
3771 A new command, "maint set profile on/off", has been added. This command can
3772 be used to enable or disable profiling while running GDB, to profile a
3773 session or a set of commands. In addition there is a new configure switch,
3774 "--enable-profiling", which will cause GDB to be compiled with profiling
3775 data, for more informative profiling results.
3777 * Default MI syntax changed to "mi2".
3779 The default MI (machine interface) syntax, enabled by the command line
3780 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3781 "mi1", can be enabled by specifying the option "-i=mi1".
3783 Support for the original "mi0" syntax (included in GDB 5.0) has been
3786 Fix for gdb/192: removed extraneous space when displaying frame level.
3787 Fix for gdb/672: update changelist is now output in mi list format.
3788 Fix for gdb/702: a -var-assign that updates the value now shows up
3789 in a subsequent -var-update.
3791 * New native configurations.
3793 FreeBSD/amd64 x86_64-*-freebsd*
3795 * Multi-arched targets.
3797 HP/PA HPUX11 hppa*-*-hpux*
3798 Renesas M32R/D w/simulator m32r-*-elf*
3800 * OBSOLETE configurations and files
3802 Configurations that have been declared obsolete in this release have
3803 been commented out. Unless there is activity to revive these
3804 configurations, the next release of GDB will have their sources
3805 permanently REMOVED.
3807 Z8000 simulator z8k-zilog-none or z8ksim
3808 Matsushita MN10200 w/simulator mn10200-*-*
3809 H8/500 simulator h8500-hitachi-hms or h8500hms
3810 HP/PA running BSD hppa*-*-bsd*
3811 HP/PA running OSF/1 hppa*-*-osf*
3812 HP/PA Pro target hppa*-*-pro*
3813 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3814 Sequent family i[3456]86-sequent-sysv4*
3815 i[3456]86-sequent-sysv*
3816 i[3456]86-sequent-bsd*
3817 Tsqware Sparclet sparclet-*-*
3818 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3820 * REMOVED configurations and files
3823 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3824 IBM AIX PS/2 i[3456]86-*-aix
3825 i386 running Mach 3.0 i[3456]86-*-mach3*
3826 i386 running Mach i[3456]86-*-mach*
3827 i386 running OSF/1 i[3456]86-*osf1mk*
3828 HP/Apollo 68k Family m68*-apollo*-sysv*,
3830 m68*-hp-bsd*, m68*-hp-hpux*
3831 Argonaut Risc Chip (ARC) arc-*-*
3832 Mitsubishi D30V d30v-*-*
3833 Fujitsu FR30 fr30-*-elf*
3834 OS/9000 i[34]86-*-os9k
3835 I960 with MON960 i960-*-coff
3837 * MIPS $fp behavior changed
3839 The convenience variable $fp, for the MIPS, now consistently returns
3840 the address of the current frame's base. Previously, depending on the
3841 context, $fp could refer to either $sp or the current frame's base
3842 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3843 The GNU Source-Level Debugger''.
3845 *** Changes in GDB 5.3:
3847 * GNU/Linux shared library multi-threaded performance improved.
3849 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3850 `/proc', in preference to `ptrace' for memory reads. This may result
3851 in an improvement in the start-up time of multi-threaded, shared
3852 library applications when run under GDB. One GDB user writes: ``loads
3853 shared libs like mad''.
3855 * ``gdbserver'' now supports multi-threaded applications on some targets
3857 Support for debugging multi-threaded applications which use
3858 the GNU/Linux LinuxThreads package has been added for
3859 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3860 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3862 * GDB now supports C/C++ preprocessor macros.
3864 GDB now expands preprocessor macro invocations in C/C++ expressions,
3865 and provides various commands for showing macro definitions and how
3868 The new command `macro expand EXPRESSION' expands any macro
3869 invocations in expression, and shows the result.
3871 The new command `show macro MACRO-NAME' shows the definition of the
3872 macro named MACRO-NAME, and where it was defined.
3874 Most compilers don't include information about macros in the debugging
3875 information by default. In GCC 3.1, for example, you need to compile
3876 your program with the options `-gdwarf-2 -g3'. If the macro
3877 information is present in the executable, GDB will read it.
3879 * Multi-arched targets.
3881 DEC Alpha (partial) alpha*-*-*
3882 DEC VAX (partial) vax-*-*
3884 National Semiconductor NS32000 (partial) ns32k-*-*
3885 Motorola 68000 (partial) m68k-*-*
3886 Motorola MCORE mcore-*-*
3890 Fujitsu FRV architecture added by Red Hat frv*-*-*
3893 * New native configurations
3895 Alpha NetBSD alpha*-*-netbsd*
3896 SH NetBSD sh*-*-netbsdelf*
3897 MIPS NetBSD mips*-*-netbsd*
3898 UltraSPARC NetBSD sparc64-*-netbsd*
3900 * OBSOLETE configurations and files
3902 Configurations that have been declared obsolete in this release have
3903 been commented out. Unless there is activity to revive these
3904 configurations, the next release of GDB will have their sources
3905 permanently REMOVED.
3907 Mitsubishi D30V d30v-*-*
3908 OS/9000 i[34]86-*-os9k
3909 IBM AIX PS/2 i[3456]86-*-aix
3910 Fujitsu FR30 fr30-*-elf*
3911 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3912 Argonaut Risc Chip (ARC) arc-*-*
3913 i386 running Mach 3.0 i[3456]86-*-mach3*
3914 i386 running Mach i[3456]86-*-mach*
3915 i386 running OSF/1 i[3456]86-*osf1mk*
3916 HP/Apollo 68k Family m68*-apollo*-sysv*,
3918 m68*-hp-bsd*, m68*-hp-hpux*
3919 I960 with MON960 i960-*-coff
3921 * OBSOLETE languages
3923 CHILL, a Pascal like language used by telecommunications companies.
3925 * REMOVED configurations and files
3927 AMD 29k family via UDI a29k-amd-udi, udi29k
3928 A29K VxWorks a29k-*-vxworks
3929 AMD 29000 embedded, using EBMON a29k-none-none
3930 AMD 29000 embedded with COFF a29k-none-coff
3931 AMD 29000 embedded with a.out a29k-none-aout
3933 testsuite/gdb.hp/gdb.threads-hp/ directory
3935 * New command "set max-user-call-depth <nnn>"
3937 This command allows the user to limit the call depth of user-defined
3938 commands. The default is 1024.
3940 * Changes in FreeBSD/i386 native debugging.
3942 Support for the "generate-core-file" has been added.
3944 * New commands "dump", "append", and "restore".
3946 These commands allow data to be copied from target memory
3947 to a bfd-format or binary file (dump and append), and back
3948 from a file into memory (restore).
3950 * Improved "next/step" support on multi-processor Alpha Tru64.
3952 The previous single-step mechanism could cause unpredictable problems,
3953 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3954 of a software single-step mechanism prevents this.
3956 *** Changes in GDB 5.2.1:
3964 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3965 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3966 Fix, by Joel Brobecker imported from mainline.
3968 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3969 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3970 Fix, by Fred Fish, imported from mainline.
3972 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3973 Surprisingly enough, it works now.
3974 By Michal Ludvig, imported from mainline.
3976 i386 hardware watchpoint support:
3977 avoid misses on second run for some targets.
3978 By Pierre Muller, imported from mainline.
3980 *** Changes in GDB 5.2:
3982 * New command "set trust-readonly-sections on[off]".
3984 This command is a hint that tells gdb that read-only sections
3985 really are read-only (ie. that their contents will not change).
3986 In this mode, gdb will go to the object file rather than the
3987 target to read memory from read-only sections (such as ".text").
3988 This can be a significant performance improvement on some
3989 (notably embedded) targets.
3991 * New command "generate-core-file" (or "gcore").
3993 This new gdb command allows the user to drop a core file of the child
3994 process state at any time. So far it's been implemented only for
3995 GNU/Linux and Solaris, but should be relatively easily ported to other
3996 hosts. Argument is core file name (defaults to core.<pid>).
3998 * New command line option
4000 GDB now accepts --pid or -p followed by a process id.
4002 * Change in command line behavior -- corefiles vs. process ids.
4004 There is a subtle behavior in the way in which GDB handles
4005 command line arguments. The first non-flag argument is always
4006 a program to debug, but the second non-flag argument may either
4007 be a corefile or a process id. Previously, GDB would attempt to
4008 open the second argument as a corefile, and if that failed, would
4009 issue a superfluous error message and then attempt to attach it as
4010 a process. Now, if the second argument begins with a non-digit,
4011 it will be treated as a corefile. If it begins with a digit,
4012 GDB will attempt to attach it as a process, and if no such process
4013 is found, will then attempt to open it as a corefile.
4015 * Changes in ARM configurations.
4017 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4018 configuration is fully multi-arch.
4020 * New native configurations
4022 ARM NetBSD arm*-*-netbsd*
4023 x86 OpenBSD i[3456]86-*-openbsd*
4024 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4025 Sparc64 running FreeBSD sparc64-*-freebsd*
4029 Sanyo XStormy16 xstormy16-elf
4031 * OBSOLETE configurations and files
4033 Configurations that have been declared obsolete in this release have
4034 been commented out. Unless there is activity to revive these
4035 configurations, the next release of GDB will have their sources
4036 permanently REMOVED.
4038 AMD 29k family via UDI a29k-amd-udi, udi29k
4039 A29K VxWorks a29k-*-vxworks
4040 AMD 29000 embedded, using EBMON a29k-none-none
4041 AMD 29000 embedded with COFF a29k-none-coff
4042 AMD 29000 embedded with a.out a29k-none-aout
4044 testsuite/gdb.hp/gdb.threads-hp/ directory
4046 * REMOVED configurations and files
4048 TI TMS320C80 tic80-*-*
4050 PowerPC Solaris powerpcle-*-solaris*
4051 PowerPC Windows NT powerpcle-*-cygwin32
4052 PowerPC Netware powerpc-*-netware*
4053 Harris/CXUX m88k m88*-harris-cxux*
4054 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4055 ns32k-utek-sysv* ns32k-utek-*
4056 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4057 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4058 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4059 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4060 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4062 * Changes to command line processing
4064 The new `--args' feature can be used to specify command-line arguments
4065 for the inferior from gdb's command line.
4067 * Changes to key bindings
4069 There is a new `operate-and-get-next' function bound to `C-o'.
4071 *** Changes in GDB 5.1.1
4073 Fix compile problem on DJGPP.
4075 Fix a problem with floating-point registers on the i386 being
4078 Fix to stop GDB crashing on .debug_str debug info.
4080 Numerous documentation fixes.
4082 Numerous testsuite fixes.
4084 *** Changes in GDB 5.1:
4086 * New native configurations
4088 Alpha FreeBSD alpha*-*-freebsd*
4089 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4090 MIPS GNU/Linux mips*-*-linux*
4091 MIPS SGI Irix 6.x mips*-sgi-irix6*
4092 ia64 AIX ia64-*-aix*
4093 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4097 Motorola 68HC11 and 68HC12 m68hc11-elf
4099 UltraSparc running GNU/Linux sparc64-*-linux*
4101 * OBSOLETE configurations and files
4103 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4104 Harris/CXUX m88k m88*-harris-cxux*
4105 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4106 ns32k-utek-sysv* ns32k-utek-*
4107 TI TMS320C80 tic80-*-*
4109 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4110 PowerPC Solaris powerpcle-*-solaris*
4111 PowerPC Windows NT powerpcle-*-cygwin32
4112 PowerPC Netware powerpc-*-netware*
4113 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4114 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4115 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4116 Apple Macintosh (MPW) host N/A
4118 stuff.c (Program to stuff files into a specially prepared space in kdb)
4119 kdb-start.c (Main loop for the standalone kernel debugger)
4121 Configurations that have been declared obsolete in this release have
4122 been commented out. Unless there is activity to revive these
4123 configurations, the next release of GDB will have their sources
4124 permanently REMOVED.
4126 * REMOVED configurations and files
4128 Altos 3068 m68*-altos-*
4129 Convex c1-*-*, c2-*-*
4131 ARM RISCix arm-*-* (as host)
4135 * GDB has been converted to ISO C.
4137 GDB's source code has been converted to ISO C. In particular, the
4138 sources are fully protoized, and rely on standard headers being
4143 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4145 * The MI enabled by default.
4147 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4148 revised and enabled by default. Packages which use GDB as a debugging
4149 engine behind a UI or another front end are encouraged to switch to
4150 using the GDB/MI interface, instead of the old annotations interface
4151 which is now deprecated.
4153 * Support for debugging Pascal programs.
4155 GDB now includes support for debugging Pascal programs. The following
4156 main features are supported:
4158 - Pascal-specific data types such as sets;
4160 - automatic recognition of Pascal sources based on file-name
4163 - Pascal-style display of data types, variables, and functions;
4165 - a Pascal expression parser.
4167 However, some important features are not yet supported.
4169 - Pascal string operations are not supported at all;
4171 - there are some problems with boolean types;
4173 - Pascal type hexadecimal constants are not supported
4174 because they conflict with the internal variables format;
4176 - support for Pascal objects and classes is not full yet;
4178 - unlike Pascal, GDB is case-sensitive for symbol names.
4180 * Changes in completion.
4182 Commands such as `shell', `run' and `set args', which pass arguments
4183 to inferior programs, now complete on file names, similar to what
4184 users expect at the shell prompt.
4186 Commands which accept locations, such as `disassemble', `print',
4187 `breakpoint', `until', etc. now complete on filenames as well as
4188 program symbols. Thus, if you type "break foob TAB", and the source
4189 files linked into the programs include `foobar.c', that file name will
4190 be one of the candidates for completion. However, file names are not
4191 considered for completion after you typed a colon that delimits a file
4192 name from a name of a function in that file, as in "break foo.c:bar".
4194 `set demangle-style' completes on available demangling styles.
4196 * New platform-independent commands:
4198 It is now possible to define a post-hook for a command as well as a
4199 hook that runs before the command. For more details, see the
4200 documentation of `hookpost' in the GDB manual.
4202 * Changes in GNU/Linux native debugging.
4204 Support for debugging multi-threaded programs has been completely
4205 revised for all platforms except m68k and sparc. You can now debug as
4206 many threads as your system allows you to have.
4208 Attach/detach is supported for multi-threaded programs.
4210 Support for SSE registers was added for x86. This doesn't work for
4211 multi-threaded programs though.
4213 * Changes in MIPS configurations.
4215 Multi-arch support is enabled for all MIPS configurations.
4217 GDB can now be built as native debugger on SGI Irix 6.x systems for
4218 debugging n32 executables. (Debugging 64-bit executables is not yet
4221 * Unified support for hardware watchpoints in all x86 configurations.
4223 Most (if not all) native x86 configurations support hardware-assisted
4224 breakpoints and watchpoints in a unified manner. This support
4225 implements debug register sharing between watchpoints, which allows to
4226 put a virtually infinite number of watchpoints on the same address,
4227 and also supports watching regions up to 16 bytes with several debug
4230 The new maintenance command `maintenance show-debug-regs' toggles
4231 debugging print-outs in functions that insert, remove, and test
4232 watchpoints and hardware breakpoints.
4234 * Changes in the DJGPP native configuration.
4236 New command ``info dos sysinfo'' displays assorted information about
4237 the CPU, OS, memory, and DPMI server.
4239 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4240 display information about segment descriptors stored in GDT, LDT, and
4243 New commands ``info dos pde'' and ``info dos pte'' display entries
4244 from Page Directory and Page Tables (for now works with CWSDPMI only).
4245 New command ``info dos address-pte'' displays the Page Table entry for
4246 a given linear address.
4248 GDB can now pass command lines longer than 126 characters to the
4249 program being debugged (requires an update to the libdbg.a library
4250 which is part of the DJGPP development kit).
4252 DWARF2 debug info is now supported.
4254 It is now possible to `step' and `next' through calls to `longjmp'.
4256 * Changes in documentation.
4258 All GDB documentation was converted to GFDL, the GNU Free
4259 Documentation License.
4261 Tracepoints-related commands are now fully documented in the GDB
4264 TUI, the Text-mode User Interface, is now documented in the manual.
4266 Tracepoints-related commands are now fully documented in the GDB
4269 The "GDB Internals" manual now has an index. It also includes
4270 documentation of `ui_out' functions, GDB coding standards, x86
4271 hardware watchpoints, and memory region attributes.
4273 * GDB's version number moved to ``version.in''
4275 The Makefile variable VERSION has been replaced by the file
4276 ``version.in''. People creating GDB distributions should update the
4277 contents of this file.
4281 GUD support is now a standard part of the EMACS distribution.
4283 *** Changes in GDB 5.0:
4285 * Improved support for debugging FP programs on x86 targets
4287 Unified and much-improved support for debugging floating-point
4288 programs on all x86 targets. In particular, ``info float'' now
4289 displays the FP registers in the same format on all x86 targets, with
4290 greater level of detail.
4292 * Improvements and bugfixes in hardware-assisted watchpoints
4294 It is now possible to watch array elements, struct members, and
4295 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4296 on x86 targets no longer erroneously trigger when the address is
4299 * Improvements in the native DJGPP version of GDB
4301 The distribution now includes all the scripts and auxiliary files
4302 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4303 machines ``out of the box''.
4305 The DJGPP version can now debug programs that use signals. It is
4306 possible to catch signals that happened in the debuggee, deliver
4307 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4308 would kill the program being debugged.) Programs that hook hardware
4309 interrupts (keyboard, timer, etc.) can also be debugged.
4311 It is now possible to debug DJGPP programs that redirect their
4312 standard handles or switch them to raw (as opposed to cooked) mode, or
4313 even close them. The command ``run < foo > bar'' works as expected,
4314 and ``info terminal'' reports useful information about the debuggee's
4315 terminal, including raw/cooked mode, redirection, etc.
4317 The DJGPP version now uses termios functions for console I/O, which
4318 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4321 DOS-style file names with drive letters are now fully supported by
4324 It is now possible to debug DJGPP programs that switch their working
4325 directory. It is also possible to rerun the debuggee any number of
4326 times without restarting GDB; thus, you can use the same setup,
4327 breakpoints, etc. for many debugging sessions.
4329 * New native configurations
4331 ARM GNU/Linux arm*-*-linux*
4332 PowerPC GNU/Linux powerpc-*-linux*
4336 Motorola MCore mcore-*-*
4337 x86 VxWorks i[3456]86-*-vxworks*
4338 PowerPC VxWorks powerpc-*-vxworks*
4339 TI TMS320C80 tic80-*-*
4341 * OBSOLETE configurations
4343 Altos 3068 m68*-altos-*
4344 Convex c1-*-*, c2-*-*
4346 ARM RISCix arm-*-* (as host)
4349 Configurations that have been declared obsolete will be commented out,
4350 but the code will be left in place. If there is no activity to revive
4351 these configurations before the next release of GDB, the sources will
4352 be permanently REMOVED.
4354 * Gould support removed
4356 Support for the Gould PowerNode and NP1 has been removed.
4358 * New features for SVR4
4360 On SVR4 native platforms (such as Solaris), if you attach to a process
4361 without first loading a symbol file, GDB will now attempt to locate and
4362 load symbols from the running process's executable file.
4364 * Many C++ enhancements
4366 C++ support has been greatly improved. Overload resolution now works properly
4367 in almost all cases. RTTI support is on the way.
4369 * Remote targets can connect to a sub-program
4371 A popen(3) style serial-device has been added. This device starts a
4372 sub-process (such as a stand-alone simulator) and then communicates
4373 with that. The sub-program to run is specified using the syntax
4374 ``|<program> <args>'' vis:
4376 (gdb) set remotedebug 1
4377 (gdb) target extended-remote |mn10300-elf-sim program-args
4379 * MIPS 64 remote protocol
4381 A long standing bug in the mips64 remote protocol where by GDB
4382 expected certain 32 bit registers (ex SR) to be transfered as 32
4383 instead of 64 bits has been fixed.
4385 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4386 added to provide backward compatibility with older versions of GDB.
4388 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4390 The command ``set remotebinarydownload'' command has been replaced by
4391 ``set remote X-packet''. Other commands in ``set remote'' family
4392 include ``set remote P-packet''.
4394 * Breakpoint commands accept ranges.
4396 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4397 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4398 ``tracepoint passcount'' also accepts a range of tracepoints.
4400 * ``apropos'' command added.
4402 The ``apropos'' command searches through command names and
4403 documentation strings, printing out matches, making it much easier to
4404 try to find a command that does what you are looking for.
4408 A new machine oriented interface (MI) has been added to GDB. This
4409 interface is designed for debug environments running GDB as a separate
4410 process. This is part of the long term libGDB project. See the
4411 "GDB/MI" chapter of the GDB manual for further information. It can be
4412 enabled by configuring with:
4414 .../configure --enable-gdbmi
4416 *** Changes in GDB-4.18:
4418 * New native configurations
4420 HP-UX 10.20 hppa*-*-hpux10.20
4421 HP-UX 11.x hppa*-*-hpux11.0*
4422 M68K GNU/Linux m68*-*-linux*
4426 Fujitsu FR30 fr30-*-elf*
4427 Intel StrongARM strongarm-*-*
4428 Mitsubishi D30V d30v-*-*
4430 * OBSOLETE configurations
4432 Gould PowerNode, NP1 np1-*-*, pn-*-*
4434 Configurations that have been declared obsolete will be commented out,
4435 but the code will be left in place. If there is no activity to revive
4436 these configurations before the next release of GDB, the sources will
4437 be permanently REMOVED.
4441 As a compatibility experiment, GDB's source files buildsym.h and
4442 buildsym.c have been converted to pure standard C, no longer
4443 containing any K&R compatibility code. We believe that all systems in
4444 use today either come with a standard C compiler, or have a GCC port
4445 available. If this is not true, please report the affected
4446 configuration to bug-gdb@gnu.org immediately. See the README file for
4447 information about getting a standard C compiler if you don't have one
4452 GDB now uses readline 2.2.
4454 * set extension-language
4456 You can now control the mapping between filename extensions and source
4457 languages by using the `set extension-language' command. For instance,
4458 you can ask GDB to treat .c files as C++ by saying
4459 set extension-language .c c++
4460 The command `info extensions' lists all of the recognized extensions
4461 and their associated languages.
4463 * Setting processor type for PowerPC and RS/6000
4465 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4466 you can use the `set processor' command to specify what variant of the
4467 PowerPC family you are debugging. The command
4471 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4472 following PowerPC and RS6000 variants:
4474 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4475 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4477 403GC IBM PowerPC 403GC
4478 505 Motorola PowerPC 505
4479 860 Motorola PowerPC 860 or 850
4480 601 Motorola PowerPC 601
4481 602 Motorola PowerPC 602
4482 603 Motorola/IBM PowerPC 603 or 603e
4483 604 Motorola PowerPC 604 or 604e
4484 750 Motorola/IBM PowerPC 750 or 750
4486 At the moment, this command just tells GDB what to name the
4487 special-purpose processor registers. Since almost all the affected
4488 registers are inaccessible to user-level programs, this command is
4489 only useful for remote debugging in its present form.
4493 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4494 more extensive support for HP-UX. Added features include shared
4495 library support, kernel threads and hardware watchpoints for 11.00,
4496 support for HP's ANSI C and C++ compilers, and a compatibility mode
4497 for xdb and dbx commands.
4501 HP's donation includes the new concept of catchpoints, which is a
4502 generalization of the old catch command. On HP-UX, it is now possible
4503 to catch exec, fork, and vfork, as well as library loading.
4505 This means that the existing catch command has changed; its first
4506 argument now specifies the type of catch to be set up. See the
4507 output of "help catch" for a list of catchpoint types.
4509 * Debugging across forks
4511 On HP-UX, you can choose which process to debug when a fork() happens
4516 HP has donated a curses-based terminal user interface (TUI). To get
4517 it, build with --enable-tui. Although this can be enabled for any
4518 configuration, at present it only works for native HP debugging.
4520 * GDB remote protocol additions
4522 A new protocol packet 'X' that writes binary data is now available.
4523 Default behavior is to try 'X', then drop back to 'M' if the stub
4524 fails to respond. The settable variable `remotebinarydownload'
4525 allows explicit control over the use of 'X'.
4527 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4528 full 64-bit address. The command
4530 set remoteaddresssize 32
4532 can be used to revert to the old behaviour. For existing remote stubs
4533 the change should not be noticed, as the additional address information
4536 In order to assist in debugging stubs, you may use the maintenance
4537 command `packet' to send any text string to the stub. For instance,
4539 maint packet heythere
4541 sends the packet "$heythere#<checksum>". Note that it is very easy to
4542 disrupt a debugging session by sending the wrong packet at the wrong
4545 The compare-sections command allows you to compare section data on the
4546 target to what is in the executable file without uploading or
4547 downloading, by comparing CRC checksums.
4549 * Tracing can collect general expressions
4551 You may now collect general expressions at tracepoints. This requires
4552 further additions to the target-side stub; see tracepoint.c and
4553 doc/agentexpr.texi for further details.
4555 * mask-address variable for Mips
4557 For Mips targets, you may control the zeroing of the upper 32 bits of
4558 a 64-bit address by entering `set mask-address on'. This is mainly
4559 of interest to users of embedded R4xxx and R5xxx processors.
4561 * Higher serial baud rates
4563 GDB's serial code now allows you to specify baud rates 57600, 115200,
4564 230400, and 460800 baud. (Note that your host system may not be able
4565 to achieve all of these rates.)
4569 The i960 configuration now includes an initial implementation of a
4570 builtin simulator, contributed by Jim Wilson.
4573 *** Changes in GDB-4.17:
4575 * New native configurations
4577 Alpha GNU/Linux alpha*-*-linux*
4578 Unixware 2.x i[3456]86-unixware2*
4579 Irix 6.x mips*-sgi-irix6*
4580 PowerPC GNU/Linux powerpc-*-linux*
4581 PowerPC Solaris powerpcle-*-solaris*
4582 Sparc GNU/Linux sparc-*-linux*
4583 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4587 Argonaut Risc Chip (ARC) arc-*-*
4588 Hitachi H8/300S h8300*-*-*
4589 Matsushita MN10200 w/simulator mn10200-*-*
4590 Matsushita MN10300 w/simulator mn10300-*-*
4591 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4592 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4593 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4594 Mitsubishi D10V w/simulator d10v-*-*
4595 Mitsubishi M32R/D w/simulator m32r-*-elf*
4596 Tsqware Sparclet sparclet-*-*
4597 NEC V850 w/simulator v850-*-*
4599 * New debugging protocols
4601 ARM with RDI protocol arm*-*-*
4602 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4603 DDB and LSI variants of PMON protocol mips*-*-*
4604 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4605 PowerPC with SDS protocol powerpc{,le}-*-eabi
4606 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4610 All configurations can now understand and use the DWARF 2 debugging
4611 format. The choice is automatic, if the symbol file contains DWARF 2
4616 GDB now includes basic Java language support. This support is
4617 only useful with Java compilers that produce native machine code.
4619 * solib-absolute-prefix and solib-search-path
4621 For SunOS and SVR4 shared libraries, you may now set the prefix for
4622 loading absolute shared library symbol files, and the search path for
4623 locating non-absolute shared library symbol files.
4625 * Live range splitting
4627 GDB can now effectively debug code for which GCC has performed live
4628 range splitting as part of its optimization. See gdb/doc/LRS for
4629 more details on the expected format of the stabs information.
4633 GDB's support for the GNU Hurd, including thread debugging, has been
4634 updated to work with current versions of the Hurd.
4638 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4639 instruction set. ARM GDB automatically detects when Thumb
4640 instructions are in use, and adjusts disassembly and backtracing
4645 GDB's MIPS target configurations now handle the MIP16 16-bit
4650 GDB now includes support for overlays; if an executable has been
4651 linked such that multiple sections are based at the same address, GDB
4652 will decide which section to use for symbolic info. You can choose to
4653 control the decision manually, using overlay commands, or implement
4654 additional target-side support and use "overlay load-target" to bring
4655 in the overlay mapping. Do "help overlay" for more detail.
4659 The command "info symbol <address>" displays information about
4660 the symbol at the specified address.
4664 The standard remote protocol now includes an extension that allows
4665 asynchronous collection and display of trace data. This requires
4666 extensive support in the target-side debugging stub. Tracing mode
4667 includes a new interaction mode in GDB and new commands: see the
4668 file tracepoint.c for more details.
4672 Configurations for embedded MIPS now include a simulator contributed
4673 by Cygnus Solutions. The simulator supports the instruction sets
4674 of most MIPS variants.
4678 Sparc configurations may now include the ERC32 simulator contributed
4679 by the European Space Agency. The simulator is not built into
4680 Sparc targets by default; configure with --enable-sim to include it.
4684 For target configurations that may include multiple variants of a
4685 basic architecture (such as MIPS and SH), you may now set the
4686 architecture explicitly. "set arch" sets, "info arch" lists
4687 the possible architectures.
4689 *** Changes in GDB-4.16:
4691 * New native configurations
4693 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4694 M68K NetBSD m68k-*-netbsd*
4695 PowerPC AIX 4.x powerpc-*-aix*
4696 PowerPC MacOS powerpc-*-macos*
4697 PowerPC Windows NT powerpcle-*-cygwin32
4698 RS/6000 AIX 4.x rs6000-*-aix4*
4702 ARM with RDP protocol arm-*-*
4703 I960 with MON960 i960-*-coff
4704 MIPS VxWorks mips*-*-vxworks*
4705 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4706 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4708 Matra Sparclet sparclet-*-*
4712 The powerpc-eabi configuration now includes the PSIM simulator,
4713 contributed by Andrew Cagney, with assistance from Mike Meissner.
4714 PSIM is a very elaborate model of the PowerPC, including not only
4715 basic instruction set execution, but also details of execution unit
4716 performance and I/O hardware. See sim/ppc/README for more details.
4720 GDB now works with Solaris 2.5.
4722 * Windows 95/NT native
4724 GDB will now work as a native debugger on Windows 95 and Windows NT.
4725 To build it from source, you must use the "gnu-win32" environment,
4726 which uses a DLL to emulate enough of Unix to run the GNU tools.
4727 Further information, binaries, and sources are available at
4728 ftp.cygnus.com, under pub/gnu-win32.
4730 * dont-repeat command
4732 If a user-defined command includes the command `dont-repeat', then the
4733 command will not be repeated if the user just types return. This is
4734 useful if the command is time-consuming to run, so that accidental
4735 extra keystrokes don't run the same command many times.
4737 * Send break instead of ^C
4739 The standard remote protocol now includes an option to send a break
4740 rather than a ^C to the target in order to interrupt it. By default,
4741 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4743 * Remote protocol timeout
4745 The standard remote protocol includes a new variable `remotetimeout'
4746 that allows you to set the number of seconds before GDB gives up trying
4747 to read from the target. The default value is 2.
4749 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4751 By default GDB will automatically keep track of objects as they are
4752 loaded and unloaded by the dynamic linker. By using the command `set
4753 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4754 when shared library events occur, thus allowing you to set breakpoints
4755 in shared libraries which are explicitly loaded by the inferior.
4757 Note this feature does not work on hpux8. On hpux9 you must link
4758 /usr/lib/end.o into your program. This feature should work
4759 automatically on hpux10.
4761 * Irix 5.x hardware watchpoint support
4763 Irix 5 configurations now support the use of hardware watchpoints.
4765 * Mips protocol "SYN garbage limit"
4767 When debugging a Mips target using the `target mips' protocol, you
4768 may set the number of characters that GDB will ignore by setting
4769 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4770 every character. The default value is 1050.
4772 * Recording and replaying remote debug sessions
4774 If you set `remotelogfile' to the name of a file, gdb will write to it
4775 a recording of a remote debug session. This recording may then be
4776 replayed back to gdb using "gdbreplay". See gdbserver/README for
4777 details. This is useful when you have a problem with GDB while doing
4778 remote debugging; you can make a recording of the session and send it
4779 to someone else, who can then recreate the problem.
4781 * Speedups for remote debugging
4783 GDB includes speedups for downloading and stepping MIPS systems using
4784 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4785 and more efficient S-record downloading.
4787 * Memory use reductions and statistics collection
4789 GDB now uses less memory and reports statistics about memory usage.
4790 Try the `maint print statistics' command, for example.
4792 *** Changes in GDB-4.15:
4794 * Psymtabs for XCOFF
4796 The symbol reader for AIX GDB now uses partial symbol tables. This
4797 can greatly improve startup time, especially for large executables.
4799 * Remote targets use caching
4801 Remote targets now use a data cache to speed up communication with the
4802 remote side. The data cache could lead to incorrect results because
4803 it doesn't know about volatile variables, thus making it impossible to
4804 debug targets which use memory mapped I/O devices. `set remotecache
4805 off' turns the the data cache off.
4807 * Remote targets may have threads
4809 The standard remote protocol now includes support for multiple threads
4810 in the target system, using new protocol commands 'H' and 'T'. See
4811 gdb/remote.c for details.
4815 If GDB is configured with `--enable-netrom', then it will include
4816 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4817 acts as though it is a bank of ROM on the target board, but you can
4818 write into it over the network. GDB's support consists only of
4819 support for fast loading into the emulated ROM; to debug, you must use
4820 another protocol, such as standard remote protocol. The usual
4821 sequence is something like
4823 target nrom <netrom-hostname>
4825 target remote <netrom-hostname>:1235
4829 GDB now includes support for the Apple Macintosh, as a host only. It
4830 may be run as either an MPW tool or as a standalone application, and
4831 it can debug through the serial port. All the usual GDB commands are
4832 available, but to the target command, you must supply "serial" as the
4833 device type instead of "/dev/ttyXX". See mpw-README in the main
4834 directory for more information on how to build. The MPW configuration
4835 scripts */mpw-config.in support only a few targets, and only the
4836 mips-idt-ecoff target has been tested.
4840 GDB configuration now uses autoconf. This is not user-visible,
4841 but does simplify configuration and building.
4845 GDB now supports hpux10.
4847 *** Changes in GDB-4.14:
4849 * New native configurations
4851 x86 FreeBSD i[345]86-*-freebsd
4852 x86 NetBSD i[345]86-*-netbsd
4853 NS32k NetBSD ns32k-*-netbsd
4854 Sparc NetBSD sparc-*-netbsd
4858 A29K VxWorks a29k-*-vxworks
4859 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4860 CPU32 EST-300 emulator m68*-*-est*
4861 PowerPC ELF powerpc-*-elf
4864 * Alpha OSF/1 support for procfs
4866 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4867 possible to attach to running processes. As the mounting of the /proc
4868 filesystem is optional on the Alpha, GDB automatically determines
4869 the availability of /proc during startup. This can lead to problems
4870 if /proc is unmounted after GDB has been started.
4872 * Arguments to user-defined commands
4874 User commands may accept up to 10 arguments separated by whitespace.
4875 Arguments are accessed within the user command via $arg0..$arg9. A
4878 print $arg0 + $arg1 + $arg2
4880 To execute the command use:
4883 Defines the command "adder" which prints the sum of its three arguments.
4884 Note the arguments are text substitutions, so they may reference variables,
4885 use complex expressions, or even perform inferior function calls.
4887 * New `if' and `while' commands
4889 This makes it possible to write more sophisticated user-defined
4890 commands. Both commands take a single argument, which is the
4891 expression to evaluate, and must be followed by the commands to
4892 execute, one per line, if the expression is nonzero, the list being
4893 terminated by the word `end'. The `if' command list may include an
4894 `else' word, which causes the following commands to be executed only
4895 if the expression is zero.
4897 * Fortran source language mode
4899 GDB now includes partial support for Fortran 77. It will recognize
4900 Fortran programs and can evaluate a subset of Fortran expressions, but
4901 variables and functions may not be handled correctly. GDB will work
4902 with G77, but does not yet know much about symbols emitted by other
4905 * Better HPUX support
4907 Most debugging facilities now work on dynamic executables for HPPAs
4908 running hpux9 or later. You can attach to running dynamically linked
4909 processes, but by default the dynamic libraries will be read-only, so
4910 for instance you won't be able to put breakpoints in them. To change
4911 that behavior do the following before running the program:
4917 This will cause the libraries to be mapped private and read-write.
4918 To revert to the normal behavior, do this:
4924 You cannot set breakpoints or examine data in the library until after
4925 the library is loaded if the function/data symbols do not have
4928 GDB can now also read debug symbols produced by the HP C compiler on
4929 HPPAs (sorry, no C++, Fortran or 68k support).
4931 * Target byte order now dynamically selectable
4933 You can choose which byte order to use with a target system, via the
4934 commands "set endian big" and "set endian little", and you can see the
4935 current setting by using "show endian". You can also give the command
4936 "set endian auto", in which case GDB will use the byte order
4937 associated with the executable. Currently, only embedded MIPS
4938 configurations support dynamic selection of target byte order.
4940 * New DOS host serial code
4942 This version uses DPMI interrupts to handle buffered I/O, so you
4943 no longer need to run asynctsr when debugging boards connected to
4946 *** Changes in GDB-4.13:
4948 * New "complete" command
4950 This lists all the possible completions for the rest of the line, if it
4951 were to be given as a command itself. This is intended for use by emacs.
4953 * Trailing space optional in prompt
4955 "set prompt" no longer adds a space for you after the prompt you set. This
4956 allows you to set a prompt which ends in a space or one that does not.
4958 * Breakpoint hit counts
4960 "info break" now displays a count of the number of times the breakpoint
4961 has been hit. This is especially useful in conjunction with "ignore"; you
4962 can ignore a large number of breakpoint hits, look at the breakpoint info
4963 to see how many times the breakpoint was hit, then run again, ignoring one
4964 less than that number, and this will get you quickly to the last hit of
4967 * Ability to stop printing at NULL character
4969 "set print null-stop" will cause GDB to stop printing the characters of
4970 an array when the first NULL is encountered. This is useful when large
4971 arrays actually contain only short strings.
4973 * Shared library breakpoints
4975 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4976 breakpoints in shared libraries before the executable is run.
4978 * Hardware watchpoints
4980 There is a new hardware breakpoint for the watch command for sparclite
4981 targets. See gdb/sparclite/hw_breakpoint.note.
4983 Hardware watchpoints are also now supported under GNU/Linux.
4987 Annotations have been added. These are for use with graphical interfaces,
4988 and are still experimental. Currently only gdba.el uses these.
4990 * Improved Irix 5 support
4992 GDB now works properly with Irix 5.2.
4994 * Improved HPPA support
4996 GDB now works properly with the latest GCC and GAS.
4998 * New native configurations
5000 Sequent PTX4 i[34]86-sequent-ptx4
5001 HPPA running OSF/1 hppa*-*-osf*
5002 Atari TT running SVR4 m68*-*-sysv4*
5003 RS/6000 LynxOS rs6000-*-lynxos*
5007 OS/9000 i[34]86-*-os9k
5008 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5011 * Hitachi SH7000 and E7000-PC ICE support
5013 There is now support for communicating with the Hitachi E7000-PC ICE.
5014 This is available automatically when GDB is configured for the SH.
5018 As usual, a variety of small fixes and improvements, both generic
5019 and configuration-specific. See the ChangeLog for more detail.
5021 *** Changes in GDB-4.12:
5023 * Irix 5 is now supported
5027 GDB-4.12 on the HPPA has a number of changes which make it unable
5028 to debug the output from the currently released versions of GCC and
5029 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5030 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5031 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5034 *** Changes in GDB-4.11:
5036 * User visible changes:
5040 The "set remotedebug" option is now consistent between the mips remote
5041 target, remote targets using the gdb-specific protocol, UDI (AMD's
5042 debug protocol for the 29k) and the 88k bug monitor. It is now an
5043 integer specifying a debug level (normally 0 or 1, but 2 means more
5044 debugging info for the mips target).
5046 * DEC Alpha native support
5048 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5049 debug info, but GDB works fairly well with the DEC compiler and should
5050 work with a future GCC release. See the README file for a few
5051 Alpha-specific notes.
5053 * Preliminary thread implementation
5055 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5057 * LynxOS native and target support for 386
5059 This release has been hosted on LynxOS 2.2, and also can be configured
5060 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5063 * Improvements in C++ mangling/demangling.
5065 This release has much better g++ debugging, specifically in name
5066 mangling/demangling, virtual function calls, print virtual table,
5067 call methods, ...etc.
5069 *** Changes in GDB-4.10:
5071 * User visible changes:
5073 Remote debugging using the GDB-specific (`target remote') protocol now
5074 supports the `load' command. This is only useful if you have some
5075 other way of getting the stub to the target system, and you can put it
5076 somewhere in memory where it won't get clobbered by the download.
5078 Filename completion now works.
5080 When run under emacs mode, the "info line" command now causes the
5081 arrow to point to the line specified. Also, "info line" prints
5082 addresses in symbolic form (as well as hex).
5084 All vxworks based targets now support a user settable option, called
5085 vxworks-timeout. This option represents the number of seconds gdb
5086 should wait for responses to rpc's. You might want to use this if
5087 your vxworks target is, perhaps, a slow software simulator or happens
5088 to be on the far side of a thin network line.
5092 This release contains support for using a DEC alpha as a GDB host for
5093 cross debugging. Native alpha debugging is not supported yet.
5096 *** Changes in GDB-4.9:
5100 This is the first GDB release which is accompanied by a matching testsuite.
5101 The testsuite requires installation of dejagnu, which should be available
5102 via ftp from most sites that carry GNU software.
5106 'Cfront' style demangling has had its name changed to 'ARM' style, to
5107 emphasize that it was written from the specifications in the C++ Annotated
5108 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5109 disclaimers, it still generated too much confusion with users attempting to
5110 use gdb with AT&T cfront.
5114 GDB now uses a standard remote interface to a simulator library.
5115 So far, the library contains simulators for the Zilog Z8001/2, the
5116 Hitachi H8/300, H8/500 and Super-H.
5118 * New targets supported
5120 H8/300 simulator h8300-hitachi-hms or h8300hms
5121 H8/500 simulator h8500-hitachi-hms or h8500hms
5122 SH simulator sh-hitachi-hms or sh
5123 Z8000 simulator z8k-zilog-none or z8ksim
5124 IDT MIPS board over serial line mips-idt-ecoff
5126 Cross-debugging to GO32 targets is supported. It requires a custom
5127 version of the i386-stub.c module which is integrated with the
5128 GO32 memory extender.
5130 * New remote protocols
5132 MIPS remote debugging protocol.
5134 * New source languages supported
5136 This version includes preliminary support for Chill, a Pascal like language
5137 used by telecommunications companies. Chill support is also being integrated
5138 into the GNU compiler, but we don't know when it will be publically available.
5141 *** Changes in GDB-4.8:
5143 * HP Precision Architecture supported
5145 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5146 version of this support was available as a set of patches from the
5147 University of Utah. GDB does not support debugging of programs
5148 compiled with the HP compiler, because HP will not document their file
5149 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5150 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5152 Many problems in the preliminary version have been fixed.
5154 * Faster and better demangling
5156 We have improved template demangling and fixed numerous bugs in the GNU style
5157 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5158 character types (wchar_t) are now supported. Demangling of each symbol is now
5159 only done once, and is cached when the symbol table for a file is read in.
5160 This results in a small increase in memory usage for C programs, a moderate
5161 increase in memory usage for C++ programs, and a fantastic speedup in
5164 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5165 from the specifications in the Annotated Reference Manual, which AT&T's
5166 compiler does not actually implement.
5168 * G++ multiple inheritance compiler problem
5170 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5171 inheritance lattices was reworked to properly discover ambiguities. We
5172 recently found an example which causes this new algorithm to fail in a
5173 very subtle way, producing bad debug information for those classes.
5174 The file 'gcc.patch' (in this directory) can be applied to gcc to
5175 circumvent the problem. A future GCC release will contain a complete
5178 The previous G++ debug info problem (mentioned below for the gdb-4.7
5179 release) is fixed in gcc version 2.3.2.
5181 * Improved configure script
5183 The `configure' script will now attempt to guess your system type if
5184 you don't supply a host system type. The old scheme of supplying a
5185 host system triplet is preferable over using this. All the magic is
5186 done in the new `config.guess' script. Examine it for details.
5188 We have also brought our configure script much more in line with the FSF's
5189 version. It now supports the --with-xxx options. In particular,
5190 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5191 The resulting GDB will not be able to read arbitrary object file formats --
5192 only the format ``expected'' to be used on the configured target system.
5193 We hope to make this the default in a future release.
5195 * Documentation improvements
5197 There's new internal documentation on how to modify GDB, and how to
5198 produce clean changes to the code. We implore people to read it
5199 before submitting changes.
5201 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5202 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5203 `info' files are also provided. To build `info' files from scratch,
5204 you will need the latest `makeinfo' release, which will be available in
5205 a future texinfo-X.Y release.
5207 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5208 We're not sure exactly which versions have this problem, but it has
5209 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5210 or better. If that isn't possible, there is a patch in
5211 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5212 around this problem.
5216 GDB now supports array constants that can be used in expressions typed in by
5217 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5218 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5221 The new directory `gdb/sparclite' contains a program that demonstrates
5222 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5224 * New native hosts supported
5226 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5227 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5229 * New targets supported
5231 AMD 29k family via UDI a29k-amd-udi or udi29k
5233 * New file formats supported
5235 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5236 HPUX core files, and SCO 3.2v2 core files.
5240 Attaching to processes now works again; thanks for the many bug reports.
5242 We have also stomped on a bunch of core dumps caused by
5243 printf_filtered("%s") problems.
5245 We eliminated a copyright problem on the rpc and ptrace header files
5246 for VxWorks, which was discovered at the last minute during the 4.7
5247 release. You should now be able to build a VxWorks GDB.
5249 You can now interrupt gdb while an attached process is running. This
5250 will cause the attached process to stop, and give control back to GDB.
5252 We fixed problems caused by using too many file descriptors
5253 for reading symbols from object files and libraries. This was
5254 especially a problem for programs that used many (~100) shared
5257 The `step' command now only enters a subroutine if there is line number
5258 information for the subroutine. Otherwise it acts like the `next'
5259 command. Previously, `step' would enter subroutines if there was
5260 any debugging information about the routine. This avoids problems
5261 when using `cc -g1' on MIPS machines.
5263 * Internal improvements
5265 GDB's internal interfaces have been improved to make it easier to support
5266 debugging of multiple languages in the future.
5268 GDB now uses a common structure for symbol information internally.
5269 Minimal symbols (derived from linkage symbols in object files), partial
5270 symbols (from a quick scan of debug information), and full symbols
5271 contain a common subset of information, making it easier to write
5272 shared code that handles any of them.
5274 * New command line options
5276 We now accept --silent as an alias for --quiet.
5280 The memory-mapped-malloc library is now licensed under the GNU Library
5281 General Public License.
5283 *** Changes in GDB-4.7:
5285 * Host/native/target split
5287 GDB has had some major internal surgery to untangle the support for
5288 hosts and remote targets. Now, when you configure GDB for a remote
5289 target, it will no longer load in all of the support for debugging
5290 local programs on the host. When fully completed and tested, this will
5291 ensure that arbitrary host/target combinations are possible.
5293 The primary conceptual shift is to separate the non-portable code in
5294 GDB into three categories. Host specific code is required any time GDB
5295 is compiled on that host, regardless of the target. Target specific
5296 code relates to the peculiarities of the target, but can be compiled on
5297 any host. Native specific code is everything else: it can only be
5298 built when the host and target are the same system. Child process
5299 handling and core file support are two common `native' examples.
5301 GDB's use of /proc for controlling Unix child processes is now cleaner.
5302 It has been split out into a single module under the `target_ops' vector,
5303 plus two native-dependent functions for each system that uses /proc.
5305 * New hosts supported
5307 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5308 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5309 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5311 * New targets supported
5313 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5314 68030 and CPU32 m68030-*-*, m68332-*-*
5316 * New native hosts supported
5318 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5319 (386bsd is not well tested yet)
5320 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5322 * New file formats supported
5324 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5325 supports reading of `a.out.adobe' object files, which are an a.out
5326 format extended with minimal information about multiple sections.
5330 `show copying' is the same as the old `info copying'.
5331 `show warranty' is the same as `info warrantee'.
5332 These were renamed for consistency. The old commands continue to work.
5334 `info handle' is a new alias for `info signals'.
5336 You can now define pre-command hooks, which attach arbitrary command
5337 scripts to any command. The commands in the hook will be executed
5338 prior to the user's command. You can also create a hook which will be
5339 executed whenever the program stops. See gdb.texinfo.
5343 We now deal with Cfront style name mangling, and can even extract type
5344 info from mangled symbols. GDB can automatically figure out which
5345 symbol mangling style your C++ compiler uses.
5347 Calling of methods and virtual functions has been improved as well.
5351 The crash that occured when debugging Sun Ansi-C compiled binaries is
5352 fixed. This was due to mishandling of the extra N_SO stabs output
5355 We also finally got Ultrix 4.2 running in house, and fixed core file
5356 support, with help from a dozen people on the net.
5358 John M. Farrell discovered that the reason that single-stepping was so
5359 slow on all of the Mips based platforms (primarily SGI and DEC) was
5360 that we were trying to demangle and lookup a symbol used for internal
5361 purposes on every instruction that was being stepped through. Changing
5362 the name of that symbol so that it couldn't be mistaken for a C++
5363 mangled symbol sped things up a great deal.
5365 Rich Pixley sped up symbol lookups in general by getting much smarter
5366 about when C++ symbol mangling is necessary. This should make symbol
5367 completion (TAB on the command line) much faster. It's not as fast as
5368 we'd like, but it's significantly faster than gdb-4.6.
5372 A new user controllable variable 'call_scratch_address' can
5373 specify the location of a scratch area to be used when GDB
5374 calls a function in the target. This is necessary because the
5375 usual method of putting the scratch area on the stack does not work
5376 in systems that have separate instruction and data spaces.
5378 We integrated changes to support the 29k UDI (Universal Debugger
5379 Interface), but discovered at the last minute that we didn't have all
5380 of the appropriate copyright paperwork. We are working with AMD to
5381 resolve this, and hope to have it available soon.
5385 We have sped up the remote serial line protocol, especially for targets
5386 with lots of registers. It now supports a new `expedited status' ('T')
5387 message which can be used in place of the existing 'S' status message.
5388 This allows the remote stub to send only the registers that GDB
5389 needs to make a quick decision about single-stepping or conditional
5390 breakpoints, eliminating the need to fetch the entire register set for
5391 each instruction being stepped through.
5393 The GDB remote serial protocol now implements a write-through cache for
5394 registers, only re-reading the registers if the target has run.
5396 There is also a new remote serial stub for SPARC processors. You can
5397 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5398 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5399 processor with a serial port.
5403 Configure.in files have become much easier to read and modify. A new
5404 `table driven' format makes it more obvious what configurations are
5405 supported, and what files each one uses.
5409 There is a new opcodes library which will eventually contain all of the
5410 disassembly routines and opcode tables. At present, it only contains
5411 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5412 disassembler (binutils/objdump) to share these routines.
5414 The libiberty library is now copylefted under the GNU Library General
5415 Public License. This allows more liberal use, and was done so libg++
5416 can use it. This makes no difference to GDB, since the Library License
5417 grants all the rights from the General Public License.
5421 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5422 reference to the stabs symbol info used by the debugger. It is (as far
5423 as we know) the only published document on this fascinating topic. We
5424 encourage you to read it, compare it to the stabs information on your
5425 system, and send improvements on the document in general (to
5426 bug-gdb@prep.ai.mit.edu).
5428 And, of course, many bugs have been fixed.
5431 *** Changes in GDB-4.6:
5433 * Better support for C++ function names
5435 GDB now accepts as input the "demangled form" of C++ overloaded function
5436 names and member function names, and can do command completion on such names
5437 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5438 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5439 Make use of command completion, it is your friend.
5441 GDB also now accepts a variety of C++ mangled symbol formats. They are
5442 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5443 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5444 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5445 for the list of formats.
5447 * G++ symbol mangling problem
5449 Recent versions of gcc have a bug in how they emit debugging information for
5450 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5451 directory) can be applied to gcc to fix the problem. Alternatively, if you
5452 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5453 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5454 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5457 * New 'maintenance' command
5459 All of the commands related to hacking GDB internals have been moved out of
5460 the main command set, and now live behind the 'maintenance' command. This
5461 can also be abbreviated as 'mt'. The following changes were made:
5463 dump-me -> maintenance dump-me
5464 info all-breakpoints -> maintenance info breakpoints
5465 printmsyms -> maintenance print msyms
5466 printobjfiles -> maintenance print objfiles
5467 printpsyms -> maintenance print psymbols
5468 printsyms -> maintenance print symbols
5470 The following commands are new:
5472 maintenance demangle Call internal GDB demangler routine to
5473 demangle a C++ link name and prints the result.
5474 maintenance print type Print a type chain for a given symbol
5476 * Change to .gdbinit file processing
5478 We now read the $HOME/.gdbinit file before processing the argv arguments
5479 (e.g. reading symbol files or core files). This allows global parameters to
5480 be set, which will apply during the symbol reading. The ./.gdbinit is still
5481 read after argv processing.
5483 * New hosts supported
5485 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5487 GNU/Linux support i386-unknown-linux or linux
5489 We are also including code to support the HP/PA running BSD and HPUX. This
5490 is almost guaranteed not to work, as we didn't have time to test or build it
5491 for this release. We are including it so that the more adventurous (or
5492 masochistic) of you can play with it. We also had major problems with the
5493 fact that the compiler that we got from HP doesn't support the -g option.
5496 * New targets supported
5498 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5500 * More smarts about finding #include files
5502 GDB now remembers the compilation directory for all include files, and for
5503 all files from which C is generated (like yacc and lex sources). This
5504 greatly improves GDB's ability to find yacc/lex sources, and include files,
5505 especially if you are debugging your program from a directory different from
5506 the one that contains your sources.
5508 We also fixed a bug which caused difficulty with listing and setting
5509 breakpoints in include files which contain C code. (In the past, you had to
5510 try twice in order to list an include file that you hadn't looked at before.)
5512 * Interesting infernals change
5514 GDB now deals with arbitrary numbers of sections, where the symbols for each
5515 section must be relocated relative to that section's landing place in the
5516 target's address space. This work was needed to support ELF with embedded
5517 stabs used by Solaris-2.0.
5519 * Bug fixes (of course!)
5521 There have been loads of fixes for the following things:
5522 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5523 i960, stabs, DOS(GO32), procfs, etc...
5525 See the ChangeLog for details.
5527 *** Changes in GDB-4.5:
5529 * New machines supported (host and target)
5531 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5533 SGI Irix-4.x mips-sgi-irix4 or iris4
5535 * New malloc package
5537 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5538 Mmalloc is capable of handling mutiple heaps of memory. It is also
5539 capable of saving a heap to a file, and then mapping it back in later.
5540 This can be used to greatly speedup the startup of GDB by using a
5541 pre-parsed symbol table which lives in a mmalloc managed heap. For
5542 more details, please read mmalloc/mmalloc.texi.
5546 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5547 'help info proc' for details.
5549 * MIPS ecoff symbol table format
5551 The code that reads MIPS symbol table format is now supported on all hosts.
5552 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5555 * File name changes for MS-DOS
5557 Many files in the config directories have been renamed to make it easier to
5558 support GDB on MS-DOSe systems (which have very restrictive file name
5559 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5560 environment) is close to working but has some remaining problems. Note
5561 that debugging of DOS programs is not supported, due to limitations
5562 in the ``operating system'', but it can be used to host cross-debugging.
5564 * Cross byte order fixes
5566 Many fixes have been made to support cross debugging of Sparc and MIPS
5567 targets from hosts whose byte order differs.
5569 * New -mapped and -readnow options
5571 If memory-mapped files are available on your system through the 'mmap'
5572 system call, you can use the -mapped option on the `file' or
5573 `symbol-file' commands to cause GDB to write the symbols from your
5574 program into a reusable file. If the program you are debugging is
5575 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5576 Future GDB debugging sessions will notice the presence of this file,
5577 and will quickly map in symbol information from it, rather than reading
5578 the symbol table from the executable program. Using the '-mapped'
5579 option in a GDB `file' or `symbol-file' command has the same effect as
5580 starting GDB with the '-mapped' command-line option.
5582 You can cause GDB to read the entire symbol table immediately by using
5583 the '-readnow' option with any of the commands that load symbol table
5584 information (or on the GDB command line). This makes the command
5585 slower, but makes future operations faster.
5587 The -mapped and -readnow options are typically combined in order to
5588 build a `fred.syms' file that contains complete symbol information.
5589 A simple GDB invocation to do nothing but build a `.syms' file for future
5592 gdb -batch -nx -mapped -readnow programname
5594 The `.syms' file is specific to the host machine on which GDB is run.
5595 It holds an exact image of GDB's internal symbol table. It cannot be
5596 shared across multiple host platforms.
5598 * longjmp() handling
5600 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5601 siglongjmp() without losing control. This feature has not yet been ported to
5602 all systems. It currently works on many 386 platforms, all MIPS-based
5603 platforms (SGI, DECstation, etc), and Sun3/4.
5607 Preliminary work has been put in to support the new Solaris OS from Sun. At
5608 this time, it can control and debug processes, but it is not capable of
5613 As always, many many bug fixes. The major areas were with g++, and mipsread.
5614 People using the MIPS-based platforms should experience fewer mysterious
5615 crashes and trashed symbol tables.
5617 *** Changes in GDB-4.4:
5619 * New machines supported (host and target)
5621 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5623 BSD Reno on Vax vax-dec-bsd
5624 Ultrix on Vax vax-dec-ultrix
5626 * New machines supported (target)
5628 AMD 29000 embedded, using EBMON a29k-none-none
5632 GDB continues to improve its handling of C++. `References' work better.
5633 The demangler has also been improved, and now deals with symbols mangled as
5634 per the Annotated C++ Reference Guide.
5636 GDB also now handles `stabs' symbol information embedded in MIPS
5637 `ecoff' symbol tables. Since the ecoff format was not easily
5638 extensible to handle new languages such as C++, this appeared to be a
5639 good way to put C++ debugging info into MIPS binaries. This option
5640 will be supported in the GNU C compiler, version 2, when it is
5643 * New features for SVR4
5645 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5646 shared libraries. Debugging dynamically linked programs should present
5647 only minor differences from debugging statically linked programs.
5649 The `info proc' command will print out information about any process
5650 on an SVR4 system (including the one you are debugging). At the moment,
5651 it prints the address mappings of the process.
5653 If you bring up GDB on another SVR4 system, please send mail to
5654 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5656 * Better dynamic linking support in SunOS
5658 Reading symbols from shared libraries which contain debugging symbols
5659 now works properly. However, there remain issues such as automatic
5660 skipping of `transfer vector' code during function calls, which
5661 make it harder to debug code in a shared library, than to debug the
5662 same code linked statically.
5666 GDB is now using the latest `getopt' routines from the FSF. This
5667 version accepts the -- prefix for options with long names. GDB will
5668 continue to accept the old forms (-option and +option) as well.
5669 Various single letter abbreviations for options have been explicity
5670 added to the option table so that they won't get overshadowed in the
5671 future by other options that begin with the same letter.
5675 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5676 Many assorted bugs have been handled. Many more remain to be handled.
5677 See the various ChangeLog files (primarily in gdb and bfd) for details.
5680 *** Changes in GDB-4.3:
5682 * New machines supported (host and target)
5684 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5685 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5686 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5688 * Almost SCO Unix support
5690 We had hoped to support:
5691 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5692 (except for core file support), but we discovered very late in the release
5693 that it has problems with process groups that render gdb unusable. Sorry
5694 about that. I encourage people to fix it and post the fixes.
5696 * Preliminary ELF and DWARF support
5698 GDB can read ELF object files on System V Release 4, and can handle
5699 debugging records for C, in DWARF format, in ELF files. This support
5700 is preliminary. If you bring up GDB on another SVR4 system, please
5701 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5706 GDB now uses the latest `readline' library. One user-visible change
5707 is that two tabs will list possible command completions, which previously
5708 required typing M-? (meta-question mark, or ESC ?).
5712 The `stepi' bug that many of you noticed has been squashed.
5713 Many bugs in C++ have been handled. Many more remain to be handled.
5714 See the various ChangeLog files (primarily in gdb and bfd) for details.
5716 * State of the MIPS world (in case you wondered):
5718 GDB can understand the symbol tables emitted by the compilers
5719 supplied by most vendors of MIPS-based machines, including DEC. These
5720 symbol tables are in a format that essentially nobody else uses.
5722 Some versions of gcc come with an assembler post-processor called
5723 mips-tfile. This program is required if you want to do source-level
5724 debugging of gcc-compiled programs. I believe FSF does not ship
5725 mips-tfile with gcc version 1, but it will eventually come with gcc
5728 Debugging of g++ output remains a problem. g++ version 1.xx does not
5729 really support it at all. (If you're lucky, you should be able to get
5730 line numbers and stack traces to work, but no parameters or local
5731 variables.) With some work it should be possible to improve the
5734 When gcc version 2 is released, you will have somewhat better luck.
5735 However, even then you will get confusing results for inheritance and
5738 We will eventually provide full debugging of g++ output on
5739 DECstations. This will probably involve some kind of stabs-in-ecoff
5740 encapulation, but the details have not been worked out yet.
5743 *** Changes in GDB-4.2:
5745 * Improved configuration
5747 Only one copy of `configure' exists now, and it is not self-modifying.
5748 Porting BFD is simpler.
5752 The `step' and `next' commands now only stop at the first instruction
5753 of a source line. This prevents the multiple stops that used to occur
5754 in switch statements, for-loops, etc. `Step' continues to stop if a
5755 function that has debugging information is called within the line.
5759 Lots of small bugs fixed. More remain.
5761 * New host supported (not target)
5763 Intel 386 PC clone running Mach i386-none-mach
5766 *** Changes in GDB-4.1:
5768 * Multiple source language support
5770 GDB now has internal scaffolding to handle several source languages.
5771 It determines the type of each source file from its filename extension,
5772 and will switch expression parsing and number formatting to match the
5773 language of the function in the currently selected stack frame.
5774 You can also specifically set the language to be used, with
5775 `set language c' or `set language modula-2'.
5779 GDB now has preliminary support for the GNU Modula-2 compiler,
5780 currently under development at the State University of New York at
5781 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5782 continue through the fall of 1991 and into 1992.
5784 Other Modula-2 compilers are currently not supported, and attempting to
5785 debug programs compiled with them will likely result in an error as the
5786 symbol table is read. Feel free to work on it, though!
5788 There are hooks in GDB for strict type checking and range checking,
5789 in the `Modula-2 philosophy', but they do not currently work.
5793 GDB can now write to executable and core files (e.g. patch
5794 a variable's value). You must turn this switch on, specify
5795 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5796 by assigning a new value to a variable. Modifications take
5799 * Automatic SunOS shared library reading
5801 When you run your program, GDB automatically determines where its
5802 shared libraries (if any) have been loaded, and reads their symbols.
5803 The `share' command is no longer needed. This also works when
5804 examining core files.
5808 You can specify the number of lines that the `list' command shows.
5811 * New machines supported (host and target)
5813 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5814 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5815 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5817 * New hosts supported (not targets)
5819 IBM RT/PC: romp-ibm-aix or rtpc
5821 * New targets supported (not hosts)
5823 AMD 29000 embedded with COFF a29k-none-coff
5824 AMD 29000 embedded with a.out a29k-none-aout
5825 Ultracomputer remote kernel debug a29k-nyu-kern
5827 * New remote interfaces
5833 *** Changes in GDB-4.0:
5837 Wide output is wrapped at good places to make the output more readable.
5839 Gdb now supports cross-debugging from a host machine of one type to a
5840 target machine of another type. Communication with the target system
5841 is over serial lines. The ``target'' command handles connecting to the
5842 remote system; the ``load'' command will download a program into the
5843 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5844 also supports debugging of realtime processes running under VxWorks,
5845 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5846 stub on the target system.
5848 New CPUs supported include the AMD 29000 and Intel 960.
5850 GDB now reads object files and symbol tables via a ``binary file''
5851 library, which allows a single copy of GDB to debug programs of multiple
5852 object file types such as a.out and coff.
5854 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5855 refcard.dvi and refcard.ps are available to format it).
5858 * Control-Variable user interface simplified
5860 All variables that control the operation of the debugger can be set
5861 by the ``set'' command, and displayed by the ``show'' command.
5863 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5864 ``Show prompt'' produces the response:
5865 Gdb's prompt is new-gdb=>.
5867 What follows are the NEW set commands. The command ``help set'' will
5868 print a complete list of old and new set commands. ``help set FOO''
5869 will give a longer description of the variable FOO. ``show'' will show
5870 all of the variable descriptions and their current settings.
5872 confirm on/off: Enables warning questions for operations that are
5873 hard to recover from, e.g. rerunning the program while
5874 it is already running. Default is ON.
5876 editing on/off: Enables EMACS style command line editing
5877 of input. Previous lines can be recalled with
5878 control-P, the current line can be edited with control-B,
5879 you can search for commands with control-R, etc.
5882 history filename NAME: NAME is where the gdb command history
5883 will be stored. The default is .gdb_history,
5884 or the value of the environment variable
5887 history size N: The size, in commands, of the command history. The
5888 default is 256, or the value of the environment variable
5891 history save on/off: If this value is set to ON, the history file will
5892 be saved after exiting gdb. If set to OFF, the
5893 file will not be saved. The default is OFF.
5895 history expansion on/off: If this value is set to ON, then csh-like
5896 history expansion will be performed on
5897 command line input. The default is OFF.
5899 radix N: Sets the default radix for input and output. It can be set
5900 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5901 in the current radix, so "set radix 10" is always a no-op.
5903 height N: This integer value is the number of lines on a page. Default
5904 is 24, the current `stty rows'' setting, or the ``li#''
5905 setting from the termcap entry matching the environment
5908 width N: This integer value is the number of characters on a line.
5909 Default is 80, the current `stty cols'' setting, or the ``co#''
5910 setting from the termcap entry matching the environment
5913 Note: ``set screensize'' is obsolete. Use ``set height'' and
5914 ``set width'' instead.
5916 print address on/off: Print memory addresses in various command displays,
5917 such as stack traces and structure values. Gdb looks
5918 more ``symbolic'' if you turn this off; it looks more
5919 ``machine level'' with it on. Default is ON.
5921 print array on/off: Prettyprint arrays. New convenient format! Default
5924 print demangle on/off: Print C++ symbols in "source" form if on,
5927 print asm-demangle on/off: Same, for assembler level printouts
5930 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5933 * Support for Epoch Environment.
5935 The epoch environment is a version of Emacs v18 with windowing. One
5936 new command, ``inspect'', is identical to ``print'', except that if you
5937 are running in the epoch environment, the value is printed in its own
5941 * Support for Shared Libraries
5943 GDB can now debug programs and core files that use SunOS shared libraries.
5944 Symbols from a shared library cannot be referenced
5945 before the shared library has been linked with the program (this
5946 happens after you type ``run'' and before the function main() is entered).
5947 At any time after this linking (including when examining core files
5948 from dynamically linked programs), gdb reads the symbols from each
5949 shared library when you type the ``sharedlibrary'' command.
5950 It can be abbreviated ``share''.
5952 sharedlibrary REGEXP: Load shared object library symbols for files
5953 matching a unix regular expression. No argument
5954 indicates to load symbols for all shared libraries.
5956 info sharedlibrary: Status of loaded shared libraries.
5961 A watchpoint stops execution of a program whenever the value of an
5962 expression changes. Checking for this slows down execution
5963 tremendously whenever you are in the scope of the expression, but is
5964 quite useful for catching tough ``bit-spreader'' or pointer misuse
5965 problems. Some machines such as the 386 have hardware for doing this
5966 more quickly, and future versions of gdb will use this hardware.
5968 watch EXP: Set a watchpoint (breakpoint) for an expression.
5970 info watchpoints: Information about your watchpoints.
5972 delete N: Deletes watchpoint number N (same as breakpoints).
5973 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5974 enable N: Re-enables watchpoint number N (same as breakpoints).
5977 * C++ multiple inheritance
5979 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5982 * C++ exception handling
5984 Gdb now supports limited C++ exception handling. Besides the existing
5985 ability to breakpoint on an exception handler, gdb can breakpoint on
5986 the raising of an exception (before the stack is peeled back to the
5989 catch FOO: If there is a FOO exception handler in the dynamic scope,
5990 set a breakpoint to catch exceptions which may be raised there.
5991 Multiple exceptions (``catch foo bar baz'') may be caught.
5993 info catch: Lists all exceptions which may be caught in the
5994 current stack frame.
5997 * Minor command changes
5999 The command ``call func (arg, arg, ...)'' now acts like the print
6000 command, except it does not print or save a value if the function's result
6001 is void. This is similar to dbx usage.
6003 The ``up'' and ``down'' commands now always print the frame they end up
6004 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6005 frames without printing.
6007 * New directory command
6009 'dir' now adds directories to the FRONT of the source search path.
6010 The path starts off empty. Source files that contain debug information
6011 about the directory in which they were compiled can be found even
6012 with an empty path; Sun CC and GCC include this information. If GDB can't
6013 find your source file in the current directory, type "dir .".
6015 * Configuring GDB for compilation
6017 For normal use, type ``./configure host''. See README or gdb.texinfo
6020 GDB now handles cross debugging. If you are remotely debugging between
6021 two different machines, type ``./configure host -target=targ''.
6022 Host is the machine where GDB will run; targ is the machine
6023 where the program that you are debugging will run.