1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.9
6 * GDB now honors the content of the file /proc/PID/coredump_filter
7 (PID is the process ID) on GNU/Linux systems. This file can be used
8 to specify the types of memory mappings that will be included in a
9 corefile. For more information, please refer to the manual page of
10 "core(5)". GDB also has a new command: "set use-coredump-filter
11 on|off". It allows to set whether GDB will read the content of the
12 /proc/PID/coredump_filter file when generating a corefile.
14 * The "info os" command on GNU/Linux can now display information on
16 "info os cpus" Listing of all cpus/cores on the system
18 * GDB has two new commands: "set serial parity odd|even|none" and
19 "show serial parity". These allows to set or show parity for the
22 * The "info source" command now displays the producer string if it was
23 present in the debug info. This typically includes the compiler version
24 and may include things like its command line arguments.
26 * The "info dll", an alias of the "info sharedlibrary" command,
27 is now available on all platforms.
29 * Directory names supplied to the "set sysroot" commands may be
30 prefixed with "target:" to tell GDB to access shared libraries from
31 the target system, be it local or remote. This replaces the prefix
32 "remote:". The default sysroot has been changed from "" to
33 "target:". "remote:" is automatically converted to "target:" for
34 backward compatibility.
36 * The system root specified by "set sysroot" will be prepended to the
37 filename of the main executable (if reported to GDB as absolute by
38 the operating system) when starting processes remotely, and when
39 attaching to already-running local or remote processes.
41 * GDB now supports automatic location and retrieval of executable
42 files from remote targets. Remote debugging can now be initiated
43 using only a "target remote" or "target extended-remote" command
44 (no "set sysroot" or "file" commands are required). See "New remote
47 * The "dump" command now supports verilog hex format.
49 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
53 ** gdb.Objfile objects have a new attribute "username",
54 which is the name of the objfile as specified by the user,
55 without, for example, resolving symlinks.
56 ** You can now write frame unwinders in Python.
57 ** gdb.Type objects have a new method "optimized_out",
58 returning optimized out gdb.Value instance of this type.
59 ** Xmethods can now specify a result type.
60 ** gdb.Value objects have new methods "reference_value" and
61 "const_value" which return a reference to the value and a
62 "const" version of the value respectively.
66 maint print symbol-cache
67 Print the contents of the symbol cache.
69 maint print symbol-cache-statistics
70 Print statistics of symbol cache usage.
72 maint flush-symbol-cache
73 Flush the contents of the symbol cache.
77 Start branch trace recording using Branch Trace Store (BTS) format.
83 Set the maximum number of candidates to be considered during
84 completion. The default value is 200. This limit allows GDB
85 to avoid generating large completion lists, the computation of
86 which can cause the debugger to become temporarily unresponsive.
88 maint set symbol-cache-size
89 maint show symbol-cache-size
90 Control the size of the symbol cache.
92 set|show record btrace bts buffer-size
93 Set and show the size of the ring buffer used for branch tracing in
95 The obtained size may differ from the requested size. Use "info
96 record" to see the obtained buffer size.
98 * The command 'thread apply all' can now support new option '-ascending'
99 to call its specified command for all threads in ascending order.
101 * Python/Guile scripting
103 ** GDB now supports auto-loading of Python/Guile scripts contained in the
104 special section named `.debug_gdb_scripts'.
108 qXfer:btrace-conf:read
109 Return the branch trace configuration for the current thread.
111 Qbtrace-conf:bts:size
112 Set the requested ring buffer size for branch tracing in BTS format.
115 Indicates a memory breakpoint instruction was executed, irrespective
116 of whether it was GDB that planted the breakpoint or the breakpoint
117 is hardcoded in the program. This is required for correct non-stop
121 Indicates the target stopped for a hardware breakpoint. This is
122 required for correct non-stop mode operation.
125 Return information about files on the remote system.
128 Return the full absolute name of the file that was executed to
129 create a process running on the remote system.
132 Indicates that a fork system call was executed.
135 Indicates that a vfork system call was executed.
137 vforkdone stop reason
138 Indicates that a vfork child of the specified process has executed
139 an exec or exit, allowing the vfork parent to resume execution.
141 fork-events and vfork-events features in qSupported
142 The qSupported packet allows GDB to request support for fork and
143 vfork events using new 'gdbfeatures' fork-events and vfork-events,
144 and the qSupported response can contain the corresponding
145 'stubfeatures'. Set and show commands can be used to display
146 whether these features are enabled.
148 * Extended-remote fork events
150 ** GDB now has support for fork events on extended-remote Linux
151 targets. For targets with Linux kernels 2.5.60 and later, this
152 enables follow-fork-mode and detach-on-fork for both fork and
153 vfork, as well as fork and vfork catchpoints.
155 * The info record command now shows the recording format and the
156 branch tracing configuration for the current thread when using
157 the btrace record target.
158 For the BTS format, it shows the ring buffer size.
160 * GDB now has support for DTrace USDT (Userland Static Defined
161 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
163 * GDB now supports access to vector registers on S/390 GNU/Linux
166 * Removed command line options
168 -xdb HP-UX XDB compatibility mode.
170 * Removed targets and native configurations
172 HP/PA running HP-UX hppa*-*-hpux*
173 Itanium running HP-UX ia64-*-hpux*
175 *** Changes in GDB 7.9
177 * GDB now supports hardware watchpoints on x86 GNU Hurd.
181 ** You can now access frame registers from Python scripts.
182 ** New attribute 'producer' for gdb.Symtab objects.
183 ** gdb.Objfile objects have a new attribute "progspace",
184 which is the gdb.Progspace object of the containing program space.
185 ** gdb.Objfile objects have a new attribute "owner".
186 ** gdb.Objfile objects have a new attribute "build_id",
187 which is the build ID generated when the file was built.
188 ** gdb.Objfile objects have a new method "add_separate_debug_file".
189 ** A new event "gdb.clear_objfiles" has been added, triggered when
190 selecting a new file to debug.
191 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
192 ** New function gdb.lookup_objfile.
194 New events which are triggered when GDB modifies the state of the
197 ** gdb.events.inferior_call_pre: Function call is about to be made.
198 ** gdb.events.inferior_call_post: Function call has just been made.
199 ** gdb.events.memory_changed: A memory location has been altered.
200 ** gdb.events.register_changed: A register has been altered.
202 * New Python-based convenience functions:
204 ** $_caller_is(name [, number_of_frames])
205 ** $_caller_matches(regexp [, number_of_frames])
206 ** $_any_caller_is(name [, number_of_frames])
207 ** $_any_caller_matches(regexp [, number_of_frames])
209 * GDB now supports the compilation and injection of source code into
210 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
211 to compile the source code to object code, and if successful, inject
212 and execute that code within the current context of the inferior.
213 Currently the C language is supported. The commands used to
214 interface with this new feature are:
216 compile code [-raw|-r] [--] [source code]
217 compile file [-raw|-r] filename
221 demangle [-l language] [--] name
222 Demangle "name" in the specified language, or the current language
223 if elided. This command is renamed from the "maint demangle" command.
224 The latter is kept as a no-op to avoid "maint demangle" being interpreted
225 as "maint demangler-warning".
227 queue-signal signal-name-or-number
228 Queue a signal to be delivered to the thread when it is resumed.
230 add-auto-load-scripts-directory directory
231 Add entries to the list of directories from which to load auto-loaded
234 maint print user-registers
235 List all currently available "user" registers.
237 compile code [-r|-raw] [--] [source code]
238 Compile, inject, and execute in the inferior the executable object
239 code produced by compiling the provided source code.
241 compile file [-r|-raw] filename
242 Compile and inject into the inferior the executable object code
243 produced by compiling the source code stored in the filename
246 * On resume, GDB now always passes the signal the program had stopped
247 for to the thread the signal was sent to, even if the user changed
248 threads before resuming. Previously GDB would often (but not
249 always) deliver the signal to the thread that happens to be current
252 * Conversely, the "signal" command now consistently delivers the
253 requested signal to the current thread. GDB now asks for
254 confirmation if the program had stopped for a signal and the user
255 switched threads meanwhile.
257 * "breakpoint always-inserted" modes "off" and "auto" merged.
259 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
260 won't remove breakpoints from the target until all threads stop,
261 even in non-stop mode. The "auto" mode has been removed, and "off"
262 is now the default mode.
266 set debug symbol-lookup
267 show debug symbol-lookup
268 Control display of debugging info regarding symbol lookup.
272 ** The -list-thread-groups command outputs an exit-code field for
273 inferiors that have exited.
277 MIPS SDE mips*-sde*-elf*
281 Support for these obsolete configurations has been removed.
283 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
284 SGI Irix-5.x mips-*-irix5*
285 SGI Irix-6.x mips-*-irix6*
286 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
287 VAX running Ultrix vax-*-ultrix*
289 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
290 and "assf"), have been removed. Use the "sharedlibrary" command, or
291 its alias "share", instead.
293 *** Changes in GDB 7.8
295 * New command line options
298 This is an alias for the --data-directory option.
300 * GDB supports printing and modifying of variable length automatic arrays
301 as specified in ISO C99.
303 * The ARM simulator now supports instruction level tracing
304 with or without disassembly.
308 GDB now has support for scripting using Guile. Whether this is
309 available is determined at configure time.
310 Guile version 2.0 or greater is required.
311 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
313 * New commands (for set/show, see "New options" below)
317 Invoke CODE by passing it to the Guile interpreter.
321 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
323 info auto-load guile-scripts [regexp]
324 Print the list of automatically loaded Guile scripts.
326 * The source command is now capable of sourcing Guile scripts.
327 This feature is dependent on the debugger being built with Guile support.
331 set print symbol-loading (off|brief|full)
332 show print symbol-loading
333 Control whether to print informational messages when loading symbol
334 information for a file. The default is "full", but when debugging
335 programs with large numbers of shared libraries the amount of output
338 set guile print-stack (none|message|full)
339 show guile print-stack
340 Show a stack trace when an error is encountered in a Guile script.
342 set auto-load guile-scripts (on|off)
343 show auto-load guile-scripts
344 Control auto-loading of Guile script files.
346 maint ada set ignore-descriptive-types (on|off)
347 maint ada show ignore-descriptive-types
348 Control whether the debugger should ignore descriptive types in Ada
349 programs. The default is not to ignore the descriptive types. See
350 the user manual for more details on descriptive types and the intended
351 usage of this option.
353 set auto-connect-native-target
355 Control whether GDB is allowed to automatically connect to the
356 native target for the run, attach, etc. commands when not connected
357 to any target yet. See also "target native" below.
359 set record btrace replay-memory-access (read-only|read-write)
360 show record btrace replay-memory-access
361 Control what memory accesses are allowed during replay.
363 maint set target-async (on|off)
364 maint show target-async
365 This controls whether GDB targets operate in synchronous or
366 asynchronous mode. Normally the default is asynchronous, if it is
367 available; but this can be changed to more easily debug problems
368 occurring only in synchronous mode.
370 set mi-async (on|off)
372 Control whether MI asynchronous mode is preferred. This supersedes
373 "set target-async" of previous GDB versions.
375 * "set target-async" is deprecated as a CLI option and is now an alias
376 for "set mi-async" (only puts MI into async mode).
378 * Background execution commands (e.g., "c&", "s&", etc.) are now
379 possible ``out of the box'' if the target supports them. Previously
380 the user would need to explicitly enable the possibility with the
381 "set target-async on" command.
383 * New features in the GDB remote stub, GDBserver
385 ** New option --debug-format=option1[,option2,...] allows one to add
386 additional text to each output. At present only timestamps
387 are supported: --debug-format=timestamps.
388 Timestamps can also be turned on with the
389 "monitor set debug-format timestamps" command from GDB.
391 * The 'record instruction-history' command now starts counting instructions
392 at one. This also affects the instruction ranges reported by the
393 'record function-call-history' command when given the /i modifier.
395 * The command 'record function-call-history' supports a new modifier '/c' to
396 indent the function names based on their call stack depth.
397 The fields for the '/i' and '/l' modifier have been reordered.
398 The source line range is now prefixed with 'at'.
399 The instruction range is now prefixed with 'inst'.
400 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
401 "record instruction-history" and "list" commands.
403 * The ranges given as arguments to the 'record function-call-history' and
404 'record instruction-history' commands are now inclusive.
406 * The btrace record target now supports the 'record goto' command.
407 For locations inside the execution trace, the back trace is computed
408 based on the information stored in the execution trace.
410 * The btrace record target supports limited reverse execution and replay.
411 The target does not record data and therefore does not allow reading
414 * The "catch syscall" command now works on s390*-linux* targets.
416 * The "compare-sections" command is no longer specific to target
417 remote. It now works with all targets.
419 * All native targets are now consistently called "native".
420 Consequently, the "target child", "target GNU", "target djgpp",
421 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
422 commands have been replaced with "target native". The QNX/NTO port
423 leaves the "procfs" target in place and adds a "native" target for
424 consistency with other ports. The impact on users should be minimal
425 as these commands previously either throwed an error, or were
426 no-ops. The target's name is visible in the output of the following
427 commands: "help target", "info target", "info files", "maint print
430 * The "target native" command now connects to the native target. This
431 can be used to launch native programs even when "set
432 auto-connect-native-target" is set to off.
434 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
436 * Support for Intel(R) AVX-512 registers on GNU/Linux.
437 Support displaying and modifying Intel(R) AVX-512 registers
438 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
442 qXfer:btrace:read's annex
443 The qXfer:btrace:read packet supports a new annex 'delta' to read
444 branch trace incrementally.
448 ** Valid Python operations on gdb.Value objects representing
449 structs/classes invoke the corresponding overloaded operators if
451 ** New `Xmethods' feature in the Python API. Xmethods are
452 additional methods or replacements for existing methods of a C++
453 class. This feature is useful for those cases where a method
454 defined in C++ source code could be inlined or optimized out by
455 the compiler, making it unavailable to GDB.
458 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
460 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
461 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
462 its alias "share", instead.
464 * The commands "set remotebaud" and "show remotebaud" are no longer
465 supported. Use "set serial baud" and "show serial baud" (respectively)
470 ** A new option "-gdb-set mi-async" replaces "-gdb-set
471 target-async". The latter is left as a deprecated alias of the
472 former for backward compatibility. If the target supports it,
473 CLI background execution commands are now always possible by
474 default, independently of whether the frontend stated a
475 preference for asynchronous execution with "-gdb-set mi-async".
476 Previously "-gdb-set target-async off" affected both MI execution
477 commands and CLI execution commands.
479 *** Changes in GDB 7.7
481 * Improved support for process record-replay and reverse debugging on
482 arm*-linux* targets. Support for thumb32 and syscall instruction
483 recording has been added.
485 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
487 * GDB now supports Fission DWP file format version 2.
488 http://gcc.gnu.org/wiki/DebugFission
490 * New convenience function "$_isvoid", to check whether an expression
491 is void. A void expression is an expression where the type of the
492 result is "void". For example, some convenience variables may be
493 "void" when evaluated (e.g., "$_exitcode" before the execution of
494 the program being debugged; or an undefined convenience variable).
495 Another example, when calling a function whose return type is
498 * The "maintenance print objfiles" command now takes an optional regexp.
500 * The "catch syscall" command now works on arm*-linux* targets.
502 * GDB now consistently shows "<not saved>" when printing values of
503 registers the debug info indicates have not been saved in the frame
504 and there's nowhere to retrieve them from
505 (callee-saved/call-clobbered registers):
510 (gdb) info registers rax
513 Before, the former would print "<optimized out>", and the latter
514 "*value not available*".
516 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
521 ** Frame filters and frame decorators have been added.
522 ** Temporary breakpoints are now supported.
523 ** Line tables representation has been added.
524 ** New attribute 'parent_type' for gdb.Field objects.
525 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
526 ** New attribute 'name' for gdb.Type objects.
530 Nios II ELF nios2*-*-elf
531 Nios II GNU/Linux nios2*-*-linux
532 Texas Instruments MSP430 msp430*-*-elf
534 * Removed native configurations
536 Support for these a.out NetBSD and OpenBSD obsolete configurations has
537 been removed. ELF variants of these configurations are kept supported.
539 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
540 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
541 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
542 i[34567]86-*-openbsd3.[0-3]
543 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
544 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
545 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
549 Like "catch throw", but catches a re-thrown exception.
551 Renamed from old "maint check-symtabs".
553 Perform consistency checks on symtabs.
555 Expand symtabs matching an optional regexp.
558 Display the details of GDB configure-time options.
560 maint set|show per-command
561 maint set|show per-command space
562 maint set|show per-command time
563 maint set|show per-command symtab
564 Enable display of per-command gdb resource usage.
566 remove-symbol-file FILENAME
567 remove-symbol-file -a ADDRESS
568 Remove a symbol file added via add-symbol-file. The file to remove
569 can be identified by its filename or by an address that lies within
570 the boundaries of this symbol file in memory.
573 info exceptions REGEXP
574 Display the list of Ada exceptions defined in the program being
575 debugged. If provided, only the exceptions whose names match REGEXP
580 set debug symfile off|on
582 Control display of debugging info regarding reading symbol files and
583 symbol tables within those files
585 set print raw frame-arguments
586 show print raw frame-arguments
587 Set/show whether to print frame arguments in raw mode,
588 disregarding any defined pretty-printers.
590 set remote trace-status-packet
591 show remote trace-status-packet
592 Set/show the use of remote protocol qTStatus packet.
596 Control display of debugging messages related to Nios II targets.
600 Control whether target-assisted range stepping is enabled.
602 set startup-with-shell
603 show startup-with-shell
604 Specifies whether Unix child processes are started via a shell or
609 Use the target memory cache for accesses to the code segment. This
610 improves performance of remote debugging (particularly disassembly).
612 * You can now use a literal value 'unlimited' for options that
613 interpret 0 or -1 as meaning "unlimited". E.g., "set
614 trace-buffer-size unlimited" is now an alias for "set
615 trace-buffer-size -1" and "set height unlimited" is now an alias for
618 * The "set debug symtab-create" debugging option of GDB has been changed to
619 accept a verbosity level. 0 means "off", 1 provides basic debugging
620 output, and values of 2 or greater provides more verbose output.
622 * New command-line options
624 Display the details of GDB configure-time options.
626 * The command 'tsave' can now support new option '-ctf' to save trace
627 buffer in Common Trace Format.
629 * Newly installed $prefix/bin/gcore acts as a shell interface for the
632 * GDB now implements the the C++ 'typeid' operator.
634 * The new convenience variable $_exception holds the exception being
635 thrown or caught at an exception-related catchpoint.
637 * The exception-related catchpoints, like "catch throw", now accept a
638 regular expression which can be used to filter exceptions by type.
640 * The new convenience variable $_exitsignal is automatically set to
641 the terminating signal number when the program being debugged dies
642 due to an uncaught signal.
646 ** All MI commands now accept an optional "--language" option.
647 Support for this feature can be verified by using the "-list-features"
648 command, which should contain "language-option".
650 ** The new command -info-gdb-mi-command allows the user to determine
651 whether a GDB/MI command is supported or not.
653 ** The "^error" result record returned when trying to execute an undefined
654 GDB/MI command now provides a variable named "code" whose content is the
655 "undefined-command" error code. Support for this feature can be verified
656 by using the "-list-features" command, which should contain
657 "undefined-command-error-code".
659 ** The -trace-save MI command can optionally save trace buffer in Common
662 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
664 ** The command -data-list-register-values now accepts an optional
665 "--skip-unavailable" option. When used, only the available registers
668 ** The new command -trace-frame-collected dumps collected variables,
669 computed expressions, tvars, memory and registers in a traceframe.
671 ** The commands -stack-list-locals, -stack-list-arguments and
672 -stack-list-variables now accept an option "--skip-unavailable".
673 When used, only the available locals or arguments are displayed.
675 ** The -exec-run command now accepts an optional "--start" option.
676 When used, the command follows the same semantics as the "start"
677 command, stopping the program's execution at the start of its
678 main subprogram. Support for this feature can be verified using
679 the "-list-features" command, which should contain
680 "exec-run-start-option".
682 ** The new commands -catch-assert and -catch-exceptions insert
683 catchpoints stopping the program when Ada exceptions are raised.
685 ** The new command -info-ada-exceptions provides the equivalent of
686 the new "info exceptions" command.
688 * New system-wide configuration scripts
689 A GDB installation now provides scripts suitable for use as system-wide
690 configuration scripts for the following systems:
694 * GDB now supports target-assigned range stepping with remote targets.
695 This improves the performance of stepping source lines by reducing
696 the number of control packets from/to GDB. See "New remote packets"
699 * GDB now understands the element 'tvar' in the XML traceframe info.
700 It has the id of the collected trace state variables.
702 * On S/390 targets that provide the transactional-execution feature,
703 the program interruption transaction diagnostic block (TDB) is now
704 represented as a number of additional "registers" in GDB.
710 The vCont packet supports a new 'r' action, that tells the remote
711 stub to step through an address range itself, without GDB
712 involvemement at each single-step.
714 qXfer:libraries-svr4:read's annex
715 The previously unused annex of the qXfer:libraries-svr4:read packet
716 is now used to support passing an argument list. The remote stub
717 reports support for this argument list to GDB's qSupported query.
718 The defined arguments are "start" and "prev", used to reduce work
719 necessary for library list updating, resulting in significant
722 * New features in the GDB remote stub, GDBserver
724 ** GDBserver now supports target-assisted range stepping. Currently
725 enabled on x86/x86_64 GNU/Linux targets.
727 ** GDBserver now adds element 'tvar' in the XML in the reply to
728 'qXfer:traceframe-info:read'. It has the id of the collected
729 trace state variables.
731 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
734 * New 'z' formatter for printing and examining memory, this displays the
735 value as hexadecimal zero padded on the left to the size of the type.
737 * GDB can now use Windows x64 unwinding data.
739 * The "set remotebaud" command has been replaced by "set serial baud".
740 Similarly, "show remotebaud" has been replaced by "show serial baud".
741 The "set remotebaud" and "show remotebaud" commands are still available
742 to provide backward compatibility with older versions of GDB.
744 *** Changes in GDB 7.6
746 * Target record has been renamed to record-full.
747 Record/replay is now enabled with the "record full" command.
748 This also affects settings that are associated with full record/replay
749 that have been moved from "set/show record" to "set/show record full":
751 set|show record full insn-number-max
752 set|show record full stop-at-limit
753 set|show record full memory-query
755 * A new record target "record-btrace" has been added. The new target
756 uses hardware support to record the control-flow of a process. It
757 does not support replaying the execution, but it implements the
758 below new commands for investigating the recorded execution log.
759 This new recording method can be enabled using:
763 The "record-btrace" target is only available on Intel Atom processors
764 and requires a Linux kernel 2.6.32 or later.
766 * Two new commands have been added for record/replay to give information
767 about the recorded execution without having to replay the execution.
768 The commands are only supported by "record btrace".
770 record instruction-history prints the execution history at
771 instruction granularity
773 record function-call-history prints the execution history at
776 * New native configurations
778 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
779 FreeBSD/powerpc powerpc*-*-freebsd
780 x86_64/Cygwin x86_64-*-cygwin*
781 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
785 ARM AArch64 aarch64*-*-elf
786 ARM AArch64 GNU/Linux aarch64*-*-linux
787 Lynx 178 PowerPC powerpc-*-lynx*178
788 x86_64/Cygwin x86_64-*-cygwin*
789 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
791 * If the configured location of system.gdbinit file (as given by the
792 --with-system-gdbinit option at configure time) is in the
793 data-directory (as specified by --with-gdb-datadir at configure
794 time) or in one of its subdirectories, then GDB will look for the
795 system-wide init file in the directory specified by the
796 --data-directory command-line option.
798 * New command line options:
800 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
801 other initialization files, unlike -nx which disables all of them.
803 * Removed command line options
805 -epoch This was used by the gdb mode in Epoch, an ancient fork of
808 * The 'ptype' and 'whatis' commands now accept an argument to control
811 * 'info proc' now works on some core files.
815 ** Vectors can be created with gdb.Type.vector.
817 ** Python's atexit.register now works in GDB.
819 ** Types can be pretty-printed via a Python API.
821 ** Python 3 is now supported (in addition to Python 2.4 or later)
823 ** New class gdb.Architecture exposes GDB's internal representation
824 of architecture in the Python API.
826 ** New method Frame.architecture returns the gdb.Architecture object
827 corresponding to the frame's architecture.
829 * New Python-based convenience functions:
831 ** $_memeq(buf1, buf2, length)
832 ** $_streq(str1, str2)
834 ** $_regex(str, regex)
836 * The 'cd' command now defaults to using '~' (the home directory) if not
839 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
840 default for GCC since November 2000.
842 * The command 'forward-search' can now be abbreviated as 'fo'.
844 * The command 'info tracepoints' can now display 'installed on target'
845 or 'not installed on target' for each non-pending location of tracepoint.
847 * New configure options
849 --enable-libmcheck/--disable-libmcheck
850 By default, development versions are built with -lmcheck on hosts
851 that support it, in order to help track memory corruption issues.
852 Release versions, on the other hand, are built without -lmcheck
853 by default. The --enable-libmcheck/--disable-libmcheck configure
854 options allow the user to override that default.
855 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
856 This configure option allows the user to build GDB with
857 libbabeltrace using which GDB can read Common Trace Format data.
859 * New commands (for set/show, see "New options" below)
862 Catch signals. This is similar to "handle", but allows commands and
863 conditions to be attached.
866 List the BFDs known to GDB.
868 python-interactive [command]
870 Start a Python interactive prompt, or evaluate the optional command
871 and print the result of expressions.
874 "py" is a new alias for "python".
876 enable type-printer [name]...
877 disable type-printer [name]...
878 Enable or disable type printers.
882 ** For the Renesas Super-H architecture, the "regs" command has been removed
883 (has been deprecated in GDB 7.5), and "info all-registers" should be used
888 set print type methods (on|off)
889 show print type methods
890 Control whether method declarations are displayed by "ptype".
891 The default is to show them.
893 set print type typedefs (on|off)
894 show print type typedefs
895 Control whether typedef definitions are displayed by "ptype".
896 The default is to show them.
898 set filename-display basename|relative|absolute
899 show filename-display
900 Control the way in which filenames is displayed.
901 The default is "relative", which preserves previous behavior.
903 set trace-buffer-size
904 show trace-buffer-size
905 Request target to change the size of trace buffer.
907 set remote trace-buffer-size-packet auto|on|off
908 show remote trace-buffer-size-packet
909 Control the use of the remote protocol `QTBuffer:size' packet.
913 Control display of debugging messages related to ARM AArch64.
916 set debug coff-pe-read
917 show debug coff-pe-read
918 Control display of debugging messages related to reading of COFF/PE
923 Control display of debugging messages related to Mach-O symbols
926 set debug notification
927 show debug notification
928 Control display of debugging info for async remote notification.
932 ** Command parameter changes are now notified using new async record
933 "=cmd-param-changed".
934 ** Trace frame changes caused by command "tfind" are now notified using
935 new async record "=traceframe-changed".
936 ** The creation, deletion and modification of trace state variables
937 are now notified using new async records "=tsv-created",
938 "=tsv-deleted" and "=tsv-modified".
939 ** The start and stop of process record are now notified using new
940 async record "=record-started" and "=record-stopped".
941 ** Memory changes are now notified using new async record
943 ** The data-disassemble command response will include a "fullname" field
944 containing the absolute file name when source has been requested.
945 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
946 command, to allow pattern filling of memory areas.
947 ** New commands "-catch-load"/"-catch-unload" added for intercepting
948 library load/unload events.
949 ** The response to breakpoint commands and breakpoint async records
950 includes an "installed" field containing a boolean state about each
951 non-pending tracepoint location is whether installed on target or not.
952 ** Output of the "-trace-status" command includes a "trace-file" field
953 containing the name of the trace file being examined. This field is
954 optional, and only present when examining a trace file.
955 ** The "fullname" field is now always present along with the "file" field,
956 even if the file cannot be found by GDB.
958 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
959 You must have the LZMA library available when configuring GDB for this
960 feature to be enabled. For more information, see:
961 http://fedoraproject.org/wiki/Features/MiniDebugInfo
966 Set the size of trace buffer. The remote stub reports support for this
967 packet to gdb's qSupported query.
970 Enable Branch Trace Store (BTS)-based branch tracing for the current
971 thread. The remote stub reports support for this packet to gdb's
975 Disable branch tracing for the current thread. The remote stub reports
976 support for this packet to gdb's qSupported query.
979 Read the traced branches for the current thread. The remote stub
980 reports support for this packet to gdb's qSupported query.
982 *** Changes in GDB 7.5
984 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
985 for more x32 ABI info.
987 * GDB now supports access to MIPS DSP registers on Linux targets.
989 * GDB now supports debugging microMIPS binaries.
991 * The "info os" command on GNU/Linux can now display information on
992 several new classes of objects managed by the operating system:
993 "info os procgroups" lists process groups
994 "info os files" lists file descriptors
995 "info os sockets" lists internet-domain sockets
996 "info os shm" lists shared-memory regions
997 "info os semaphores" lists semaphores
998 "info os msg" lists message queues
999 "info os modules" lists loaded kernel modules
1001 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1002 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1003 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1004 options and inspect the probe arguments using the new $_probe_arg family
1005 of convenience variables. You can obtain more information about SystemTap
1006 in <http://sourceware.org/systemtap/>.
1008 * GDB now supports reversible debugging on ARM, it allows you to
1009 debug basic ARM and THUMB instructions, and provides
1010 record/replay support.
1012 * The option "symbol-reloading" has been deleted as it is no longer used.
1016 ** GDB commands implemented in Python can now be put in command class
1019 ** The "maint set python print-stack on|off" is now deleted.
1021 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1022 apply "flag enum"-style pretty-printing to any enum.
1024 ** gdb.lookup_symbol can now work when there is no current frame.
1026 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1027 the source at which the symbol was defined.
1029 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1030 method 'value'. The former indicates whether the symbol needs a
1031 frame in order to compute its value, and the latter computes the
1034 ** A new method 'referenced_value' on gdb.Value objects which can
1035 dereference pointer as well as C++ reference values.
1037 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1038 which return the global and static blocks (as gdb.Block objects),
1039 of the underlying symbol table, respectively.
1041 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1042 object associated with a PC value.
1044 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1045 of the address range occupied by code for the current source line.
1047 * Go language support.
1048 GDB now supports debugging programs written in the Go programming
1051 * GDBserver now supports stdio connections.
1052 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1054 * The binary "gdbtui" can no longer be built or installed.
1055 Use "gdb -tui" instead.
1057 * GDB will now print "flag" enums specially. A flag enum is one where
1058 all the enumerator values have no bits in common when pairwise
1059 "and"ed. When printing a value whose type is a flag enum, GDB will
1060 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1061 (gdb) print (enum E) 3
1064 * The filename part of a linespec will now match trailing components
1065 of a source file name. For example, "break gcc/expr.c:1000" will
1066 now set a breakpoint in build/gcc/expr.c, but not
1067 build/libcpp/expr.c.
1069 * The "info proc" and "generate-core-file" commands will now also
1070 work on remote targets connected to GDBserver on Linux.
1072 * The command "info catch" has been removed. It has been disabled
1073 since December 2007.
1075 * The "catch exception" and "catch assert" commands now accept
1076 a condition at the end of the command, much like the "break"
1077 command does. For instance:
1079 (gdb) catch exception Constraint_Error if Barrier = True
1081 Previously, it was possible to add a condition to such catchpoints,
1082 but it had to be done as a second step, after the catchpoint had been
1083 created, using the "condition" command.
1085 * The "info static-tracepoint-marker" command will now also work on
1086 native Linux targets with in-process agent.
1088 * GDB can now set breakpoints on inlined functions.
1090 * The .gdb_index section has been updated to include symbols for
1091 inlined functions. GDB will ignore older .gdb_index sections by
1092 default, which could cause symbol files to be loaded more slowly
1093 until their .gdb_index sections can be recreated. The new command
1094 "set use-deprecated-index-sections on" will cause GDB to use any older
1095 .gdb_index sections it finds. This will restore performance, but the
1096 ability to set breakpoints on inlined functions will be lost in symbol
1097 files with older .gdb_index sections.
1099 The .gdb_index section has also been updated to record more information
1100 about each symbol. This speeds up the "info variables", "info functions"
1101 and "info types" commands when used with programs having the .gdb_index
1102 section, as well as speeding up debugging with shared libraries using
1103 the .gdb_index section.
1105 * Ada support for GDB/MI Variable Objects has been added.
1107 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1112 ** New command -info-os is the MI equivalent of "info os".
1114 ** Output logs ("set logging" and related) now include MI output.
1118 ** "set use-deprecated-index-sections on|off"
1119 "show use-deprecated-index-sections on|off"
1120 Controls the use of deprecated .gdb_index sections.
1122 ** "catch load" and "catch unload" can be used to stop when a shared
1123 library is loaded or unloaded, respectively.
1125 ** "enable count" can be used to auto-disable a breakpoint after
1128 ** "info vtbl" can be used to show the virtual method tables for
1129 C++ and Java objects.
1131 ** "explore" and its sub commands "explore value" and "explore type"
1132 can be used to recursively explore values and types of
1133 expressions. These commands are available only if GDB is
1134 configured with '--with-python'.
1136 ** "info auto-load" shows status of all kinds of auto-loaded files,
1137 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1138 sequences of commands files, "info auto-load python-scripts"
1139 shows status of auto-loading Python script files,
1140 "info auto-load local-gdbinit" shows status of loading init file
1141 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1142 status of inferior specific thread debugging shared library loading.
1144 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1145 and "show auto-load-scripts" commands have been deprecated, use their
1146 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1147 and "show auto-load python-scripts" counterparts instead.
1149 ** "dprintf location,format,args..." creates a dynamic printf, which
1150 is basically a breakpoint that does a printf and immediately
1151 resumes your program's execution, so it is like a printf that you
1152 can insert dynamically at runtime instead of at compiletime.
1154 ** "set print symbol"
1156 Controls whether GDB attempts to display the symbol, if any,
1157 corresponding to addresses it prints. This defaults to "on", but
1158 you can set it to "off" to restore GDB's previous behavior.
1160 * Deprecated commands
1162 ** For the Renesas Super-H architecture, the "regs" command has been
1163 deprecated, and "info all-registers" should be used instead.
1167 Renesas RL78 rl78-*-elf
1168 HP OpenVMS ia64 ia64-hp-openvms*
1170 * GDBserver supports evaluation of breakpoint conditions. When
1171 support is advertised by GDBserver, GDB may be told to send the
1172 breakpoint conditions in bytecode form to GDBserver. GDBserver
1173 will only report the breakpoint trigger to GDB when its condition
1178 set mips compression
1179 show mips compression
1180 Select the compressed ISA encoding used in functions that have no symbol
1181 information available. The encoding can be set to either of:
1184 and is updated automatically from ELF file flags if available.
1186 set breakpoint condition-evaluation
1187 show breakpoint condition-evaluation
1188 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1189 GDBserver ("target"). Default option "auto" chooses the most efficient
1191 This option can improve debugger efficiency depending on the speed of the
1195 Disable auto-loading globally.
1198 Show auto-loading setting of all kinds of auto-loaded files.
1200 set auto-load gdb-scripts on|off
1201 show auto-load gdb-scripts
1202 Control auto-loading of GDB canned sequences of commands files.
1204 set auto-load python-scripts on|off
1205 show auto-load python-scripts
1206 Control auto-loading of Python script files.
1208 set auto-load local-gdbinit on|off
1209 show auto-load local-gdbinit
1210 Control loading of init file (.gdbinit) from current directory.
1212 set auto-load libthread-db on|off
1213 show auto-load libthread-db
1214 Control auto-loading of inferior specific thread debugging shared library.
1216 set auto-load scripts-directory <dir1>[:<dir2>...]
1217 show auto-load scripts-directory
1218 Set a list of directories from which to load auto-loaded scripts.
1219 Automatically loaded Python scripts and GDB scripts are located in one
1220 of the directories listed by this option.
1221 The delimiter (':' above) may differ according to the host platform.
1223 set auto-load safe-path <dir1>[:<dir2>...]
1224 show auto-load safe-path
1225 Set a list of directories from which it is safe to auto-load files.
1226 The delimiter (':' above) may differ according to the host platform.
1228 set debug auto-load on|off
1229 show debug auto-load
1230 Control display of debugging info for auto-loading the files above.
1232 set dprintf-style gdb|call|agent
1234 Control the way in which a dynamic printf is performed; "gdb"
1235 requests a GDB printf command, while "call" causes dprintf to call a
1236 function in the inferior. "agent" requests that the target agent
1237 (such as GDBserver) do the printing.
1239 set dprintf-function <expr>
1240 show dprintf-function
1241 set dprintf-channel <expr>
1242 show dprintf-channel
1243 Set the function and optional first argument to the call when using
1244 the "call" style of dynamic printf.
1246 set disconnected-dprintf on|off
1247 show disconnected-dprintf
1248 Control whether agent-style dynamic printfs continue to be in effect
1249 after GDB disconnects.
1251 * New configure options
1253 --with-auto-load-dir
1254 Configure default value for the 'set auto-load scripts-directory'
1255 setting above. It defaults to '$debugdir:$datadir/auto-load',
1256 $debugdir representing global debugging info directories (available
1257 via 'show debug-file-directory') and $datadir representing GDB's data
1258 directory (available via 'show data-directory').
1260 --with-auto-load-safe-path
1261 Configure default value for the 'set auto-load safe-path' setting
1262 above. It defaults to the --with-auto-load-dir setting.
1264 --without-auto-load-safe-path
1265 Set 'set auto-load safe-path' to '/', effectively disabling this
1268 * New remote packets
1270 z0/z1 conditional breakpoints extension
1272 The z0/z1 breakpoint insertion packets have been extended to carry
1273 a list of conditional expressions over to the remote stub depending on the
1274 condition evaluation mode. The use of this extension can be controlled
1275 via the "set remote conditional-breakpoints-packet" command.
1279 Specify the signals which the remote stub may pass to the debugged
1280 program without GDB involvement.
1282 * New command line options
1284 --init-command=FILE, -ix Like --command, -x but execute it
1285 before loading inferior.
1286 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1287 execute it before loading inferior.
1289 *** Changes in GDB 7.4
1291 * GDB now handles ambiguous linespecs more consistently; the existing
1292 FILE:LINE support has been expanded to other types of linespecs. A
1293 breakpoint will now be set on all matching locations in all
1294 inferiors, and locations will be added or removed according to
1297 * GDB now allows you to skip uninteresting functions and files when
1298 stepping with the "skip function" and "skip file" commands.
1300 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1301 and "show remote hardware-watchpoint-length-limit". These allows to
1302 set or show the maximum length limit (in bytes) of a remote
1303 target hardware watchpoint.
1305 This allows e.g. to use "unlimited" hardware watchpoints with the
1306 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1307 watchpoints are slower than real hardware watchpoints but are
1308 significantly faster than gdb software watchpoints.
1312 ** The register_pretty_printer function in module gdb.printing now takes
1313 an optional `replace' argument. If True, the new printer replaces any
1316 ** The "maint set python print-stack on|off" command has been
1317 deprecated and will be deleted in GDB 7.5.
1318 A new command: "set python print-stack none|full|message" has
1319 replaced it. Additionally, the default for "print-stack" is
1320 now "message", which just prints the error message without
1323 ** A prompt substitution hook (prompt_hook) is now available to the
1326 ** A new Python module, gdb.prompt has been added to the GDB Python
1327 modules library. This module provides functionality for
1328 escape sequences in prompts (used by set/show
1329 extended-prompt). These escape sequences are replaced by their
1330 corresponding value.
1332 ** Python commands and convenience-functions located in
1333 'data-directory'/python/gdb/command and
1334 'data-directory'/python/gdb/function are now automatically loaded
1337 ** Blocks now provide four new attributes. global_block and
1338 static_block will return the global and static blocks
1339 respectively. is_static and is_global are boolean attributes
1340 that indicate if the block is one of those two types.
1342 ** Symbols now provide the "type" attribute, the type of the symbol.
1344 ** The "gdb.breakpoint" function has been deprecated in favor of
1347 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1348 of a function. This class is based on the "finish" command
1349 available in the CLI.
1351 ** Type objects for struct and union types now allow access to
1352 the fields using standard Python dictionary (mapping) methods.
1353 For example, "some_type['myfield']" now works, as does
1354 "some_type.items()".
1356 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1359 ** A new function, "deep_items" has been added to the gdb.types
1360 module in the GDB Python modules library. This function returns
1361 an iterator over the fields of a struct or union type. Unlike
1362 the standard Python "iteritems" method, it will recursively traverse
1363 any anonymous fields.
1367 ** "*stopped" events can report several new "reason"s, such as
1370 ** Breakpoint changes are now notified using new async records, like
1371 "=breakpoint-modified".
1373 ** New command -ada-task-info.
1375 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1376 $sdir specifies the default system locations of shared libraries.
1377 $pdir specifies the directory where the libpthread used by the application
1380 GDB no longer looks in $sdir and $pdir after it has searched the directories
1381 mentioned in libthread-db-search-path. If you want to search those
1382 directories, they must be specified in libthread-db-search-path.
1383 The default value of libthread-db-search-path on GNU/Linux and Solaris
1384 systems is now "$sdir:$pdir".
1386 $pdir is not supported by gdbserver, it is currently ignored.
1387 $sdir is supported by gdbserver.
1389 * New configure option --with-iconv-bin.
1390 When using the internationalization support like the one in the GNU C
1391 library, GDB will invoke the "iconv" program to get a list of supported
1392 character sets. If this program lives in a non-standard location, one can
1393 use this option to specify where to find it.
1395 * When natively debugging programs on PowerPC BookE processors running
1396 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1397 watchpoints, which specify a mask in addition to an address to watch.
1398 The mask specifies that some bits of an address (the bits which are
1399 reset in the mask) should be ignored when matching the address accessed
1400 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1401 section in the user manual for more details.
1403 * The new option --once causes GDBserver to stop listening for connections once
1404 the first connection is made. The listening port used by GDBserver will
1405 become available after that.
1407 * New commands "info macros" and "alias" have been added.
1409 * New function parameters suffix @entry specifies value of function parameter
1410 at the time the function got called. Entry values are available only since
1416 "!" is now an alias of the "shell" command.
1417 Note that no space is needed between "!" and SHELL COMMAND.
1421 watch EXPRESSION mask MASK_VALUE
1422 The watch command now supports the mask argument which allows creation
1423 of masked watchpoints, if the current architecture supports this feature.
1425 info auto-load-scripts [REGEXP]
1426 This command was formerly named "maintenance print section-scripts".
1427 It is now generally useful and is no longer a maintenance-only command.
1429 info macro [-all] [--] MACRO
1430 The info macro command has new options `-all' and `--'. The first for
1431 printing all definitions of a macro. The second for explicitly specifying
1432 the end of arguments and the beginning of the macro name in case the macro
1433 name starts with a hyphen.
1435 collect[/s] EXPRESSIONS
1436 The tracepoint collect command now takes an optional modifier "/s"
1437 that directs it to dereference pointer-to-character types and
1438 collect the bytes of memory up to a zero byte. The behavior is
1439 similar to what you see when you use the regular print command on a
1440 string. An optional integer following the "/s" sets a bound on the
1441 number of bytes that will be collected.
1444 The trace start command now interprets any supplied arguments as a
1445 note to be recorded with the trace run, with an effect similar to
1446 setting the variable trace-notes.
1449 The trace stop command now interprets any arguments as a note to be
1450 mentioned along with the tstatus report that the trace was stopped
1451 with a command. The effect is similar to setting the variable
1454 * Tracepoints can now be enabled and disabled at any time after a trace
1455 experiment has been started using the standard "enable" and "disable"
1456 commands. It is now possible to start a trace experiment with no enabled
1457 tracepoints; GDB will display a warning, but will allow the experiment to
1458 begin, assuming that tracepoints will be enabled as needed while the trace
1461 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1462 locations with 4-byte instructions, when they were previously
1463 limited to locations with instructions of 5 bytes or longer.
1467 set debug dwarf2-read
1468 show debug dwarf2-read
1469 Turns on or off display of debugging messages related to reading
1470 DWARF debug info. The default is off.
1472 set debug symtab-create
1473 show debug symtab-create
1474 Turns on or off display of debugging messages related to symbol table
1475 creation. The default is off.
1478 show extended-prompt
1479 Set the GDB prompt, and allow escape sequences to be inserted to
1480 display miscellaneous information (see 'help set extended-prompt'
1481 for the list of sequences). This prompt (and any information
1482 accessed through the escape sequences) is updated every time the
1483 prompt is displayed.
1485 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1486 show print entry-values
1487 Set printing of frame argument values at function entry. In some cases
1488 GDB can determine the value of function argument which was passed by the
1489 function caller, even if the value was modified inside the called function.
1491 set debug entry-values
1492 show debug entry-values
1493 Control display of debugging info for determining frame argument values at
1494 function entry and virtual tail call frames.
1496 set basenames-may-differ
1497 show basenames-may-differ
1498 Set whether a source file may have multiple base names.
1499 (A "base name" is the name of a file with the directory part removed.
1500 Example: The base name of "/home/user/hello.c" is "hello.c".)
1501 If set, GDB will canonicalize file names (e.g., expand symlinks)
1502 before comparing them. Canonicalization is an expensive operation,
1503 but it allows the same file be known by more than one base name.
1504 If not set (the default), all source files are assumed to have just
1505 one base name, and gdb will do file name comparisons more efficiently.
1511 Set a user name and notes for the current and any future trace runs.
1512 This is useful for long-running and/or disconnected traces, to
1513 inform others (or yourself) as to who is running the trace, supply
1514 contact information, or otherwise explain what is going on.
1516 set trace-stop-notes
1517 show trace-stop-notes
1518 Set a note attached to the trace run, that is displayed when the
1519 trace has been stopped by a tstop command. This is useful for
1520 instance as an explanation, if you are stopping a trace run that was
1521 started by someone else.
1523 * New remote packets
1527 Dynamically enable a tracepoint in a started trace experiment.
1531 Dynamically disable a tracepoint in a started trace experiment.
1535 Set the user and notes of the trace run.
1539 Query the current status of a tracepoint.
1543 Query the minimum length of instruction at which a fast tracepoint may
1546 * Dcache size (number of lines) and line-size are now runtime-configurable
1547 via "set dcache line" and "set dcache line-size" commands.
1551 Texas Instruments TMS320C6x tic6x-*-*
1555 Renesas RL78 rl78-*-elf
1557 *** Changes in GDB 7.3.1
1559 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1561 *** Changes in GDB 7.3
1563 * GDB has a new command: "thread find [REGEXP]".
1564 It finds the thread id whose name, target id, or thread extra info
1565 matches the given regular expression.
1567 * The "catch syscall" command now works on mips*-linux* targets.
1569 * The -data-disassemble MI command now supports modes 2 and 3 for
1570 dumping the instruction opcodes.
1572 * New command line options
1574 -data-directory DIR Specify DIR as the "data-directory".
1575 This is mostly for testing purposes.
1577 * The "maint set python auto-load on|off" command has been renamed to
1578 "set auto-load-scripts on|off".
1580 * GDB has a new command: "set directories".
1581 It is like the "dir" command except that it replaces the
1582 source path list instead of augmenting it.
1584 * GDB now understands thread names.
1586 On GNU/Linux, "info threads" will display the thread name as set by
1587 prctl or pthread_setname_np.
1589 There is also a new command, "thread name", which can be used to
1590 assign a name internally for GDB to display.
1593 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1594 has been integrated into GDB.
1598 ** The function gdb.Write now accepts an optional keyword 'stream'.
1599 This keyword, when provided, will direct the output to either
1600 stdout, stderr, or GDB's logging output.
1602 ** Parameters can now be be sub-classed in Python, and in particular
1603 you may implement the get_set_doc and get_show_doc functions.
1604 This improves how Parameter set/show documentation is processed
1605 and allows for more dynamic content.
1607 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1608 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1609 have an is_valid method.
1611 ** Breakpoints can now be sub-classed in Python, and in particular
1612 you may implement a 'stop' function that is executed each time
1613 the inferior reaches that breakpoint.
1615 ** New function gdb.lookup_global_symbol looks up a global symbol.
1617 ** GDB values in Python are now callable if the value represents a
1618 function. For example, if 'some_value' represents a function that
1619 takes two integer parameters and returns a value, you can call
1620 that function like so:
1622 result = some_value (10,20)
1624 ** Module gdb.types has been added.
1625 It contains a collection of utilities for working with gdb.Types objects:
1626 get_basic_type, has_field, make_enum_dict.
1628 ** Module gdb.printing has been added.
1629 It contains utilities for writing and registering pretty-printers.
1630 New classes: PrettyPrinter, SubPrettyPrinter,
1631 RegexpCollectionPrettyPrinter.
1632 New function: register_pretty_printer.
1634 ** New commands "info pretty-printers", "enable pretty-printer" and
1635 "disable pretty-printer" have been added.
1637 ** gdb.parameter("directories") is now available.
1639 ** New function gdb.newest_frame returns the newest frame in the
1642 ** The gdb.InferiorThread class has a new "name" attribute. This
1643 holds the thread's name.
1645 ** Python Support for Inferior events.
1646 Python scripts can add observers to be notified of events
1647 occurring in the process being debugged.
1648 The following events are currently supported:
1649 - gdb.events.cont Continue event.
1650 - gdb.events.exited Inferior exited event.
1651 - gdb.events.stop Signal received, and Breakpoint hit events.
1655 ** GDB now puts template parameters in scope when debugging in an
1656 instantiation. For example, if you have:
1658 template<int X> int func (void) { return X; }
1660 then if you step into func<5>, "print X" will show "5". This
1661 feature requires proper debuginfo support from the compiler; it
1662 was added to GCC 4.5.
1664 ** The motion commands "next", "finish", "until", and "advance" now
1665 work better when exceptions are thrown. In particular, GDB will
1666 no longer lose control of the inferior; instead, the GDB will
1667 stop the inferior at the point at which the exception is caught.
1668 This functionality requires a change in the exception handling
1669 code that was introduced in GCC 4.5.
1671 * GDB now follows GCC's rules on accessing volatile objects when
1672 reading or writing target state during expression evaluation.
1673 One notable difference to prior behavior is that "print x = 0"
1674 no longer generates a read of x; the value of the assignment is
1675 now always taken directly from the value being assigned.
1677 * GDB now has some support for using labels in the program's source in
1678 linespecs. For instance, you can use "advance label" to continue
1679 execution to a label.
1681 * GDB now has support for reading and writing a new .gdb_index
1682 section. This section holds a fast index of DWARF debugging
1683 information and can be used to greatly speed up GDB startup and
1684 operation. See the documentation for `save gdb-index' for details.
1686 * The "watch" command now accepts an optional "-location" argument.
1687 When used, this causes GDB to watch the memory referred to by the
1688 expression. Such a watchpoint is never deleted due to it going out
1691 * GDB now supports thread debugging of core dumps on GNU/Linux.
1693 GDB now activates thread debugging using the libthread_db library
1694 when debugging GNU/Linux core dumps, similarly to when debugging
1695 live processes. As a result, when debugging a core dump file, GDB
1696 is now able to display pthread_t ids of threads. For example, "info
1697 threads" shows the same output as when debugging the process when it
1698 was live. In earlier releases, you'd see something like this:
1701 * 1 LWP 6780 main () at main.c:10
1703 While now you see this:
1706 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1708 It is also now possible to inspect TLS variables when debugging core
1711 When debugging a core dump generated on a machine other than the one
1712 used to run GDB, you may need to point GDB at the correct
1713 libthread_db library with the "set libthread-db-search-path"
1714 command. See the user manual for more details on this command.
1716 * When natively debugging programs on PowerPC BookE processors running
1717 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1718 which stop execution of the inferior whenever it executes an instruction
1719 at any address within the specified range. See the "PowerPC Embedded"
1720 section in the user manual for more details.
1722 * New features in the GDB remote stub, GDBserver
1724 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1725 and i686 LynxOS (version 5.x).
1727 ** GDBserver is now supported on Blackfin Linux.
1729 * New native configurations
1731 ia64 HP-UX ia64-*-hpux*
1735 Analog Devices, Inc. Blackfin Processor bfin-*
1737 * Ada task switching is now supported on sparc-elf targets when
1738 debugging a program using the Ravenscar Profile. For more information,
1739 see the "Tasking Support when using the Ravenscar Profile" section
1740 in the GDB user manual.
1742 * Guile support was removed.
1744 * New features in the GNU simulator
1746 ** The --map-info flag lists all known core mappings.
1748 ** CFI flashes may be simulated via the "cfi" device.
1750 *** Changes in GDB 7.2
1752 * Shared library support for remote targets by default
1754 When GDB is configured for a generic, non-OS specific target, like
1755 for example, --target=arm-eabi or one of the many *-*-elf targets,
1756 GDB now queries remote stubs for loaded shared libraries using the
1757 `qXfer:libraries:read' packet. Previously, shared library support
1758 was always disabled for such configurations.
1762 ** Argument Dependent Lookup (ADL)
1764 In C++ ADL lookup directs function search to the namespaces of its
1765 arguments even if the namespace has not been imported.
1775 Here the compiler will search for `foo' in the namespace of 'b'
1776 and find A::foo. GDB now supports this. This construct is commonly
1777 used in the Standard Template Library for operators.
1779 ** Improved User Defined Operator Support
1781 In addition to member operators, GDB now supports lookup of operators
1782 defined in a namespace and imported with a `using' directive, operators
1783 defined in the global scope, operators imported implicitly from an
1784 anonymous namespace, and the ADL operators mentioned in the previous
1786 GDB now also supports proper overload resolution for all the previously
1787 mentioned flavors of operators.
1789 ** static const class members
1791 Printing of static const class members that are initialized in the
1792 class definition has been fixed.
1794 * Windows Thread Information Block access.
1796 On Windows targets, GDB now supports displaying the Windows Thread
1797 Information Block (TIB) structure. This structure is visible either
1798 by using the new command `info w32 thread-information-block' or, by
1799 dereferencing the new convenience variable named `$_tlb', a
1800 thread-specific pointer to the TIB. This feature is also supported
1801 when remote debugging using GDBserver.
1803 * Static tracepoints
1805 Static tracepoints are calls in the user program into a tracing
1806 library. One such library is a port of the LTTng kernel tracer to
1807 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1808 When debugging with GDBserver, GDB now supports combining the GDB
1809 tracepoint machinery with such libraries. For example: the user can
1810 use GDB to probe a static tracepoint marker (a call from the user
1811 program into the tracing library) with the new "strace" command (see
1812 "New commands" below). This creates a "static tracepoint" in the
1813 breakpoint list, that can be manipulated with the same feature set
1814 as fast and regular tracepoints. E.g., collect registers, local and
1815 global variables, collect trace state variables, and define
1816 tracepoint conditions. In addition, the user can collect extra
1817 static tracepoint marker specific data, by collecting the new
1818 $_sdata internal variable. When analyzing the trace buffer, you can
1819 inspect $_sdata like any other variable available to GDB. For more
1820 information, see the "Tracepoints" chapter in GDB user manual. New
1821 remote packets have been defined to support static tracepoints, see
1822 the "New remote packets" section below.
1824 * Better reconstruction of tracepoints after disconnected tracing
1826 GDB will attempt to download the original source form of tracepoint
1827 definitions when starting a trace run, and then will upload these
1828 upon reconnection to the target, resulting in a more accurate
1829 reconstruction of the tracepoints that are in use on the target.
1833 You can now exercise direct control over the ways that GDB can
1834 affect your program. For instance, you can disallow the setting of
1835 breakpoints, so that the program can run continuously (assuming
1836 non-stop mode). In addition, the "observer" variable is available
1837 to switch all of the different controls; in observer mode, GDB
1838 cannot affect the target's behavior at all, which is useful for
1839 tasks like diagnosing live systems in the field.
1841 * The new convenience variable $_thread holds the number of the
1844 * New remote packets
1848 Return the address of the Windows Thread Information Block of a given thread.
1852 In response to several of the tracepoint packets, the target may now
1853 also respond with a number of intermediate `qRelocInsn' request
1854 packets before the final result packet, to have GDB handle
1855 relocating an instruction to execute at a different address. This
1856 is particularly useful for stubs that support fast tracepoints. GDB
1857 reports support for this feature in the qSupported packet.
1861 List static tracepoint markers in the target program.
1865 List static tracepoint markers at a given address in the target
1868 qXfer:statictrace:read
1870 Read the static trace data collected (by a `collect $_sdata'
1871 tracepoint action). The remote stub reports support for this packet
1872 to gdb's qSupported query.
1876 Send the current settings of GDB's permission flags.
1880 Send part of the source (textual) form of a tracepoint definition,
1881 which includes location, conditional, and action list.
1883 * The source command now accepts a -s option to force searching for the
1884 script in the source search path even if the script name specifies
1887 * New features in the GDB remote stub, GDBserver
1889 - GDBserver now support tracepoints (including fast tracepoints, and
1890 static tracepoints). The feature is currently supported by the
1891 i386-linux and amd64-linux builds. See the "Tracepoints support
1892 in gdbserver" section in the manual for more information.
1894 GDBserver JIT compiles the tracepoint's conditional agent
1895 expression bytecode into native code whenever possible for low
1896 overhead dynamic tracepoints conditionals. For such tracepoints,
1897 an expression that examines program state is evaluated when the
1898 tracepoint is reached, in order to determine whether to capture
1899 trace data. If the condition is simple and false, processing the
1900 tracepoint finishes very quickly and no data is gathered.
1902 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1903 for static tracepoints support.
1905 - GDBserver now supports x86_64 Windows 64-bit debugging.
1907 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1908 it understands register description.
1910 * The --batch flag now disables pagination and queries.
1912 * X86 general purpose registers
1914 GDB now supports reading/writing byte, word and double-word x86
1915 general purpose registers directly. This means you can use, say,
1916 $ah or $ax to refer, respectively, to the byte register AH and
1917 16-bit word register AX that are actually portions of the 32-bit
1918 register EAX or 64-bit register RAX.
1920 * The `commands' command now accepts a range of breakpoints to modify.
1921 A plain `commands' following a command that creates multiple
1922 breakpoints affects all the breakpoints set by that command. This
1923 applies to breakpoints set by `rbreak', and also applies when a
1924 single `break' command creates multiple breakpoints (e.g.,
1925 breakpoints on overloaded c++ functions).
1927 * The `rbreak' command now accepts a filename specification as part of
1928 its argument, limiting the functions selected by the regex to those
1929 in the specified file.
1931 * Support for remote debugging Windows and SymbianOS shared libraries
1932 from Unix hosts has been improved. Non Windows GDB builds now can
1933 understand target reported file names that follow MS-DOS based file
1934 system semantics, such as file names that include drive letters and
1935 use the backslash character as directory separator. This makes it
1936 possible to transparently use the "set sysroot" and "set
1937 solib-search-path" on Unix hosts to point as host copies of the
1938 target's shared libraries. See the new command "set
1939 target-file-system-kind" described below, and the "Commands to
1940 specify files" section in the user manual for more information.
1944 eval template, expressions...
1945 Convert the values of one or more expressions under the control
1946 of the string template to a command line, and call it.
1948 set target-file-system-kind unix|dos-based|auto
1949 show target-file-system-kind
1950 Set or show the assumed file system kind for target reported file
1953 save breakpoints <filename>
1954 Save all current breakpoint definitions to a file suitable for use
1955 in a later debugging session. To read the saved breakpoint
1956 definitions, use the `source' command.
1958 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1961 info static-tracepoint-markers
1962 Display information about static tracepoint markers in the target.
1964 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1965 Define a static tracepoint by probing a marker at the given
1966 function, line, address, or marker ID.
1970 Enable and disable observer mode.
1972 set may-write-registers on|off
1973 set may-write-memory on|off
1974 set may-insert-breakpoints on|off
1975 set may-insert-tracepoints on|off
1976 set may-insert-fast-tracepoints on|off
1977 set may-interrupt on|off
1978 Set individual permissions for GDB effects on the target. Note that
1979 some of these settings can have undesirable or surprising
1980 consequences, particularly when changed in the middle of a session.
1981 For instance, disabling the writing of memory can prevent
1982 breakpoints from being inserted, cause single-stepping to fail, or
1983 even crash your program, if you disable after breakpoints have been
1984 inserted. However, GDB should not crash.
1986 set record memory-query on|off
1987 show record memory-query
1988 Control whether to stop the inferior if memory changes caused
1989 by an instruction cannot be recorded.
1994 The disassemble command now supports "start,+length" form of two arguments.
1998 ** GDB now provides a new directory location, called the python directory,
1999 where Python scripts written for GDB can be installed. The location
2000 of that directory is <data-directory>/python, where <data-directory>
2001 is the GDB data directory. For more details, see section `Scripting
2002 GDB using Python' in the manual.
2004 ** The GDB Python API now has access to breakpoints, symbols, symbol
2005 tables, program spaces, inferiors, threads and frame's code blocks.
2006 Additionally, GDB Parameters can now be created from the API, and
2007 manipulated via set/show in the CLI.
2009 ** New functions gdb.target_charset, gdb.target_wide_charset,
2010 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2012 ** New exception gdb.GdbError.
2014 ** Pretty-printers are now also looked up in the current program space.
2016 ** Pretty-printers can now be individually enabled and disabled.
2018 ** GDB now looks for names of Python scripts to auto-load in a
2019 special section named `.debug_gdb_scripts', in addition to looking
2020 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2022 * Tracepoint actions were unified with breakpoint commands. In particular,
2023 there are no longer differences in "info break" output for breakpoints and
2024 tracepoints and the "commands" command can be used for both tracepoints and
2025 regular breakpoints.
2029 ARM Symbian arm*-*-symbianelf*
2031 * D language support.
2032 GDB now supports debugging programs written in the D programming
2035 * GDB now supports the extended ptrace interface for PowerPC which is
2036 available since Linux kernel version 2.6.34. This automatically enables
2037 any hardware breakpoints and additional hardware watchpoints available in
2038 the processor. The old ptrace interface exposes just one hardware
2039 watchpoint and no hardware breakpoints.
2041 * GDB is now able to use the Data Value Compare (DVC) register available on
2042 embedded PowerPC processors to implement in hardware simple watchpoint
2043 conditions of the form:
2045 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2047 This works in native GDB running on Linux kernels with the extended ptrace
2048 interface mentioned above.
2050 *** Changes in GDB 7.1
2054 ** Namespace Support
2056 GDB now supports importing of namespaces in C++. This enables the
2057 user to inspect variables from imported namespaces. Support for
2058 namepace aliasing has also been added. So, if a namespace is
2059 aliased in the current scope (e.g. namepace C=A; ) the user can
2060 print variables using the alias (e.g. (gdb) print C::x).
2064 All known bugs relating to the printing of virtual base class were
2065 fixed. It is now possible to call overloaded static methods using a
2070 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2071 and reinterpret_cast<> are now handled by the C++ expression parser.
2075 Xilinx MicroBlaze microblaze-*-*
2080 Xilinx MicroBlaze microblaze
2083 * Multi-program debugging.
2085 GDB now has support for multi-program (a.k.a. multi-executable or
2086 multi-exec) debugging. This allows for debugging multiple inferiors
2087 simultaneously each running a different program under the same GDB
2088 session. See "Debugging Multiple Inferiors and Programs" in the
2089 manual for more information. This implied some user visible changes
2090 in the multi-inferior support. For example, "info inferiors" now
2091 lists inferiors that are not running yet or that have exited
2092 already. See also "New commands" and "New options" below.
2094 * New tracing features
2096 GDB's tracepoint facility now includes several new features:
2098 ** Trace state variables
2100 GDB tracepoints now include support for trace state variables, which
2101 are variables managed by the target agent during a tracing
2102 experiment. They are useful for tracepoints that trigger each
2103 other, so for instance one tracepoint can count hits in a variable,
2104 and then a second tracepoint has a condition that is true when the
2105 count reaches a particular value. Trace state variables share the
2106 $-syntax of GDB convenience variables, and can appear in both
2107 tracepoint actions and condition expressions. Use the "tvariable"
2108 command to create, and "info tvariables" to view; see "Trace State
2109 Variables" in the manual for more detail.
2113 GDB now includes an option for defining fast tracepoints, which
2114 targets may implement more efficiently, such as by installing a jump
2115 into the target agent rather than a trap instruction. The resulting
2116 speedup can be by two orders of magnitude or more, although the
2117 tradeoff is that some program locations on some target architectures
2118 might not allow fast tracepoint installation, for instance if the
2119 instruction to be replaced is shorter than the jump. To request a
2120 fast tracepoint, use the "ftrace" command, with syntax identical to
2121 the regular trace command.
2123 ** Disconnected tracing
2125 It is now possible to detach GDB from the target while it is running
2126 a trace experiment, then reconnect later to see how the experiment
2127 is going. In addition, a new variable disconnected-tracing lets you
2128 tell the target agent whether to continue running a trace if the
2129 connection is lost unexpectedly.
2133 GDB now has the ability to save the trace buffer into a file, and
2134 then use that file as a target, similarly to you can do with
2135 corefiles. You can select trace frames, print data that was
2136 collected in them, and use tstatus to display the state of the
2137 tracing run at the moment that it was saved. To create a trace
2138 file, use "tsave <filename>", and to use it, do "target tfile
2141 ** Circular trace buffer
2143 You can ask the target agent to handle the trace buffer as a
2144 circular buffer, discarding the oldest trace frames to make room for
2145 newer ones, by setting circular-trace-buffer to on. This feature may
2146 not be available for all target agents.
2151 The disassemble command, when invoked with two arguments, now requires
2152 the arguments to be comma-separated.
2155 The info variables command now displays variable definitions. Files
2156 which only declare a variable are not shown.
2159 The source command is now capable of sourcing Python scripts.
2160 This feature is dependent on the debugger being build with Python
2163 Related to this enhancement is also the introduction of a new command
2164 "set script-extension" (see below).
2166 * New commands (for set/show, see "New options" below)
2168 record save [<FILENAME>]
2169 Save a file (in core file format) containing the process record
2170 execution log for replay debugging at a later time.
2172 record restore <FILENAME>
2173 Restore the process record execution log that was saved at an
2174 earlier time, for replay debugging.
2176 add-inferior [-copies <N>] [-exec <FILENAME>]
2179 clone-inferior [-copies <N>] [ID]
2180 Make a new inferior ready to execute the same program another
2181 inferior has loaded.
2186 maint info program-spaces
2187 List the program spaces loaded into GDB.
2189 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2190 show remote interrupt-sequence
2191 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2192 as the sequence to the remote target in order to interrupt the execution.
2193 Ctrl-C is a default. Some system prefers BREAK which is high level of
2194 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2195 Magic SysRq g. It is BREAK signal and character 'g'.
2197 set remote interrupt-on-connect [on | off]
2198 show remote interrupt-on-connect
2199 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2200 remote target when gdb connects to it. This is needed when you debug
2203 set remotebreak [on | off]
2205 Deprecated. Use "set/show remote interrupt-sequence" instead.
2207 tvariable $NAME [ = EXP ]
2208 Create or modify a trace state variable.
2211 List trace state variables and their values.
2213 delete tvariable $NAME ...
2214 Delete one or more trace state variables.
2217 Evaluate the given expressions without collecting anything into the
2218 trace buffer. (Valid in tracepoint actions only.)
2220 ftrace FN / FILE:LINE / *ADDR
2221 Define a fast tracepoint at the given function, line, or address.
2223 * New expression syntax
2225 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2226 GDB now parses 0b101010 identically with 42.
2230 set follow-exec-mode new|same
2231 show follow-exec-mode
2232 Control whether GDB reuses the same inferior across an exec call or
2233 creates a new one. This is useful to be able to restart the old
2234 executable after the inferior having done an exec call.
2236 set default-collect EXPR, ...
2237 show default-collect
2238 Define a list of expressions to be collected at each tracepoint.
2239 This is a useful way to ensure essential items are not overlooked,
2240 such as registers or a critical global variable.
2242 set disconnected-tracing
2243 show disconnected-tracing
2244 If set to 1, the target is instructed to continue tracing if it
2245 loses its connection to GDB. If 0, the target is to stop tracing
2248 set circular-trace-buffer
2249 show circular-trace-buffer
2250 If set to on, the target is instructed to use a circular trace buffer
2251 and discard the oldest trace frames instead of stopping the trace due
2252 to a full trace buffer. If set to off, the trace stops when the buffer
2253 fills up. Some targets may not support this.
2255 set script-extension off|soft|strict
2256 show script-extension
2257 If set to "off", the debugger does not perform any script language
2258 recognition, and all sourced files are assumed to be GDB scripts.
2259 If set to "soft" (the default), files are sourced according to
2260 filename extension, falling back to GDB scripts if the first
2262 If set to "strict", files are sourced according to filename extension.
2264 set ada trust-PAD-over-XVS on|off
2265 show ada trust-PAD-over-XVS
2266 If off, activate a workaround against a bug in the debugging information
2267 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2268 the GCC sources for more information about the GNAT encoding and
2269 PAD types in particular). It is always safe to set this option to
2270 off, but this introduces a slight performance penalty. The default
2273 * Python API Improvements
2275 ** GDB provides the new class gdb.LazyString. This is useful in
2276 some pretty-printing cases. The new method gdb.Value.lazy_string
2277 provides a simple way to create objects of this type.
2279 ** The fields returned by gdb.Type.fields now have an
2280 `is_base_class' attribute.
2282 ** The new method gdb.Type.range returns the range of an array type.
2284 ** The new method gdb.parse_and_eval can be used to parse and
2285 evaluate an expression.
2287 * New remote packets
2290 Define a trace state variable.
2293 Get the current value of a trace state variable.
2296 Set desired tracing behavior upon disconnection.
2299 Set the trace buffer to be linear or circular.
2302 Get data about the tracepoints currently in use.
2306 Process record now works correctly with hardware watchpoints.
2308 Multiple bug fixes have been made to the mips-irix port, making it
2309 much more reliable. In particular:
2310 - Debugging threaded applications is now possible again. Previously,
2311 GDB would hang while starting the program, or while waiting for
2312 the program to stop at a breakpoint.
2313 - Attaching to a running process no longer hangs.
2314 - An error occurring while loading a core file has been fixed.
2315 - Changing the value of the PC register now works again. This fixes
2316 problems observed when using the "jump" command, or when calling
2317 a function from GDB, or even when assigning a new value to $pc.
2318 - With the "finish" and "return" commands, the return value for functions
2319 returning a small array is now correctly printed.
2320 - It is now possible to break on shared library code which gets executed
2321 during a shared library init phase (code executed while executing
2322 their .init section). Previously, the breakpoint would have no effect.
2323 - GDB is now able to backtrace through the signal handler for
2324 non-threaded programs.
2326 PIE (Position Independent Executable) programs debugging is now supported.
2327 This includes debugging execution of PIC (Position Independent Code) shared
2328 libraries although for that, it should be possible to run such libraries as an
2331 *** Changes in GDB 7.0
2333 * GDB now has an interface for JIT compilation. Applications that
2334 dynamically generate code can create symbol files in memory and register
2335 them with GDB. For users, the feature should work transparently, and
2336 for JIT developers, the interface is documented in the GDB manual in the
2337 "JIT Compilation Interface" chapter.
2339 * Tracepoints may now be conditional. The syntax is as for
2340 breakpoints; either an "if" clause appended to the "trace" command,
2341 or the "condition" command is available. GDB sends the condition to
2342 the target for evaluation using the same bytecode format as is used
2343 for tracepoint actions.
2345 * The disassemble command now supports: an optional /r modifier, print the
2346 raw instructions in hex as well as in symbolic form, and an optional /m
2347 modifier to print mixed source+assembly.
2349 * Process record and replay
2351 In a architecture environment that supports ``process record and
2352 replay'', ``process record and replay'' target can record a log of
2353 the process execution, and replay it with both forward and reverse
2356 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2357 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2358 set execution-direction {forward|reverse}, for targets that support
2361 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2362 feature is available with a native GDB running on kernel version
2365 * GDB now has support for multi-byte and wide character sets on the
2366 target. Strings whose character type is wchar_t, char16_t, or
2367 char32_t are now correctly printed. GDB supports wide- and unicode-
2368 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2369 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2370 `printf'. This feature requires iconv to work properly; if your
2371 system does not have a working iconv, GDB can use GNU libiconv. See
2372 the installation instructions for more information.
2374 * GDB now supports automatic retrieval of shared library files from
2375 remote targets. To use this feature, specify a system root that begins
2376 with the `remote:' prefix, either via the `set sysroot' command or via
2377 the `--with-sysroot' configure-time option.
2379 * "info sharedlibrary" now takes an optional regex of libraries to show,
2380 and it now reports if a shared library has no debugging information.
2382 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2383 now complete on file names.
2385 * When completing in expressions, gdb will attempt to limit
2386 completions to allowable structure or union fields, where appropriate.
2387 For instance, consider:
2389 # struct example { int f1; double f2; };
2390 # struct example variable;
2393 If the user types TAB at the end of this command line, the available
2394 completions will be "f1" and "f2".
2396 * Inlined functions are now supported. They show up in backtraces, and
2397 the "step", "next", and "finish" commands handle them automatically.
2399 * GDB now supports the token-splicing (##) and stringification (#)
2400 operators when expanding macros. It also supports variable-arity
2403 * GDB now supports inspecting extra signal information, exported by
2404 the new $_siginfo convenience variable. The feature is currently
2405 implemented on linux ARM, i386 and amd64.
2407 * GDB can now display the VFP floating point registers and NEON vector
2408 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2409 can provide these registers (requires Linux 2.6.30 or later). Remote
2410 and simulator targets may also provide them.
2412 * New remote packets
2415 Search memory for a sequence of bytes.
2418 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2419 operation over reliable transport links. Use of this packet is
2420 controlled by the `set remote noack-packet' command.
2423 Kill the process with the specified process ID. Use this in preference
2424 to `k' when multiprocess protocol extensions are supported.
2427 Obtains additional operating system information
2431 Read or write additional signal information.
2433 * Removed remote protocol undocumented extension
2435 An undocumented extension to the remote protocol's `S' stop reply
2436 packet that permited the stub to pass a process id was removed.
2437 Remote servers should use the `T' stop reply packet instead.
2439 * GDB now supports multiple function calling conventions according to the
2440 DWARF-2 DW_AT_calling_convention function attribute.
2442 * The SH target utilizes the aforementioned change to distinguish between gcc
2443 and Renesas calling convention. It also adds the new CLI commands
2444 `set/show sh calling-convention'.
2446 * GDB can now read compressed debug sections, as produced by GNU gold
2447 with the --compress-debug-sections=zlib flag.
2449 * 64-bit core files are now supported on AIX.
2451 * Thread switching is now supported on Tru64.
2453 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2454 which will be allocated using malloc later in program execution.
2456 * The qXfer:libraries:read remote procotol packet now allows passing a
2457 list of section offsets.
2459 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2460 conditions handling signals delivered during attach or thread creation
2461 have also been fixed.
2463 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2464 From the user's standpoint, all unqualified instances of True and False
2465 are treated as the standard definitions, regardless of context.
2467 * GDB now parses C++ symbol and type names more flexibly. For
2470 template<typename T> class C { };
2473 GDB will now correctly handle all of:
2475 ptype C<char const *>
2476 ptype C<char const*>
2477 ptype C<const char *>
2478 ptype C<const char*>
2480 * New features in the GDB remote stub, gdbserver
2482 - The "--wrapper" command-line argument tells gdbserver to use a
2483 wrapper program to launch programs for debugging.
2485 - On PowerPC and S/390 targets, it is now possible to use a single
2486 gdbserver executable to debug both 32-bit and 64-bit programs.
2487 (This requires gdbserver itself to be built as a 64-bit executable.)
2489 - gdbserver uses the new noack protocol mode for TCP connections to
2490 reduce communications latency, if also supported and enabled in GDB.
2492 - Support for the sparc64-linux-gnu target is now included in
2495 - The amd64-linux build of gdbserver now supports debugging both
2496 32-bit and 64-bit programs.
2498 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2499 now support hardware watchpoints, and will use them automatically
2504 GDB now has support for scripting using Python. Whether this is
2505 available is determined at configure time.
2507 New GDB commands can now be written in Python.
2509 * Ada tasking support
2511 Ada tasks can now be inspected in GDB. The following commands have
2515 Print the list of Ada tasks.
2517 Print detailed information about task number N.
2519 Print the task number of the current task.
2521 Switch the context of debugging to task number N.
2523 * Support for user-defined prefixed commands. The "define" command can
2524 add new commands to existing prefixes, e.g. "target".
2526 * Multi-inferior, multi-process debugging.
2528 GDB now has generalized support for multi-inferior debugging. See
2529 "Debugging Multiple Inferiors" in the manual for more information.
2530 Although availability still depends on target support, the command
2531 set is more uniform now. The GNU/Linux specific multi-forks support
2532 has been migrated to this new framework. This implied some user
2533 visible changes; see "New commands" and also "Removed commands"
2536 * Target descriptions can now describe the target OS ABI. See the
2537 "Target Description Format" section in the user manual for more
2540 * Target descriptions can now describe "compatible" architectures
2541 to indicate that the target can execute applications for a different
2542 architecture in addition to those for the main target architecture.
2543 See the "Target Description Format" section in the user manual for
2546 * Multi-architecture debugging.
2548 GDB now includes general supports for debugging applications on
2549 hybrid systems that use more than one single processor architecture
2550 at the same time. Each such hybrid architecture still requires
2551 specific support to be added. The only hybrid architecture supported
2552 in this version of GDB is the Cell Broadband Engine.
2554 * GDB now supports integrated debugging of Cell/B.E. applications that
2555 use both the PPU and SPU architectures. To enable support for hybrid
2556 Cell/B.E. debugging, you need to configure GDB to support both the
2557 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2558 --enable-targets configure option.
2560 * Non-stop mode debugging.
2562 For some targets, GDB now supports an optional mode of operation in
2563 which you can examine stopped threads while other threads continue
2564 to execute freely. This is referred to as non-stop mode, with the
2565 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2566 section in the user manual for more information.
2568 To be able to support remote non-stop debugging, a remote stub needs
2569 to implement the non-stop mode remote protocol extensions, as
2570 described in the "Remote Non-Stop" section of the user manual. The
2571 GDB remote stub, gdbserver, has been adjusted to support these
2572 extensions on linux targets.
2574 * New commands (for set/show, see "New options" below)
2576 catch syscall [NAME(S) | NUMBER(S)]
2577 Catch system calls. Arguments, which should be names of system
2578 calls or their numbers, mean catch only those syscalls. Without
2579 arguments, every syscall will be caught. When the inferior issues
2580 any of the specified syscalls, GDB will stop and announce the system
2581 call, both when it is called and when its call returns. This
2582 feature is currently available with a native GDB running on the
2583 Linux Kernel, under the following architectures: x86, x86_64,
2584 PowerPC and PowerPC64.
2586 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2588 Search memory for a sequence of bytes.
2590 maint set python print-stack
2591 maint show python print-stack
2592 Show a stack trace when an error is encountered in a Python script.
2595 Invoke CODE by passing it to the Python interpreter.
2600 These allow macros to be defined, undefined, and listed
2604 Show operating system information about processes.
2607 List the inferiors currently under GDB's control.
2610 Switch focus to inferior number NUM.
2613 Detach from inferior number NUM.
2616 Kill inferior number NUM.
2620 set spu stop-on-load
2621 show spu stop-on-load
2622 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2624 set spu auto-flush-cache
2625 show spu auto-flush-cache
2626 Control whether to automatically flush the software-managed cache
2627 during Cell/B.E. debugging.
2629 set sh calling-convention
2630 show sh calling-convention
2631 Control the calling convention used when calling SH target functions.
2634 show debug timestamp
2635 Control display of timestamps with GDB debugging output.
2637 set disassemble-next-line
2638 show disassemble-next-line
2639 Control display of disassembled source lines or instructions when
2642 set remote noack-packet
2643 show remote noack-packet
2644 Set/show the use of remote protocol QStartNoAckMode packet. See above
2645 under "New remote packets."
2647 set remote query-attached-packet
2648 show remote query-attached-packet
2649 Control use of remote protocol `qAttached' (query-attached) packet.
2651 set remote read-siginfo-object
2652 show remote read-siginfo-object
2653 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2656 set remote write-siginfo-object
2657 show remote write-siginfo-object
2658 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2661 set remote reverse-continue
2662 show remote reverse-continue
2663 Control use of remote protocol 'bc' (reverse-continue) packet.
2665 set remote reverse-step
2666 show remote reverse-step
2667 Control use of remote protocol 'bs' (reverse-step) packet.
2669 set displaced-stepping
2670 show displaced-stepping
2671 Control displaced stepping mode. Displaced stepping is a way to
2672 single-step over breakpoints without removing them from the debuggee.
2673 Also known as "out-of-line single-stepping".
2676 show debug displaced
2677 Control display of debugging info for displaced stepping.
2679 maint set internal-error
2680 maint show internal-error
2681 Control what GDB does when an internal error is detected.
2683 maint set internal-warning
2684 maint show internal-warning
2685 Control what GDB does when an internal warning is detected.
2690 Use a wrapper program to launch programs for debugging.
2692 set multiple-symbols (all|ask|cancel)
2693 show multiple-symbols
2694 The value of this variable can be changed to adjust the debugger behavior
2695 when an expression or a breakpoint location contains an ambiguous symbol
2696 name (an overloaded function name, for instance).
2698 set breakpoint always-inserted
2699 show breakpoint always-inserted
2700 Keep breakpoints always inserted in the target, as opposed to inserting
2701 them when resuming the target, and removing them when the target stops.
2702 This option can improve debugger performance on slow remote targets.
2704 set arm fallback-mode (arm|thumb|auto)
2705 show arm fallback-mode
2706 set arm force-mode (arm|thumb|auto)
2708 These commands control how ARM GDB determines whether instructions
2709 are ARM or Thumb. The default for both settings is auto, which uses
2710 the current CPSR value for instructions without symbols; previous
2711 versions of GDB behaved as if "set arm fallback-mode arm".
2713 set disable-randomization
2714 show disable-randomization
2715 Standalone programs run with the virtual address space randomization enabled
2716 by default on some platforms. This option keeps the addresses stable across
2717 multiple debugging sessions.
2721 Control whether other threads are stopped or not when some thread hits
2726 Requests that asynchronous execution is enabled in the target, if available.
2727 In this case, it's possible to resume target in the background, and interact
2728 with GDB while the target is running. "show target-async" displays the
2729 current state of asynchronous execution of the target.
2731 set target-wide-charset
2732 show target-wide-charset
2733 The target-wide-charset is the name of the character set that GDB
2734 uses when printing characters whose type is wchar_t.
2736 set tcp auto-retry (on|off)
2738 set tcp connect-timeout
2739 show tcp connect-timeout
2740 These commands allow GDB to retry failed TCP connections to a remote stub
2741 with a specified timeout period; this is useful if the stub is launched
2742 in parallel with GDB but may not be ready to accept connections immediately.
2744 set libthread-db-search-path
2745 show libthread-db-search-path
2746 Control list of directories which GDB will search for appropriate
2749 set schedule-multiple (on|off)
2750 show schedule-multiple
2751 Allow GDB to resume all threads of all processes or only threads of
2752 the current process.
2756 Use more aggressive caching for accesses to the stack. This improves
2757 performance of remote debugging (particularly backtraces) without
2758 affecting correctness.
2760 set interactive-mode (on|off|auto)
2761 show interactive-mode
2762 Control whether GDB runs in interactive mode (on) or not (off).
2763 When in interactive mode, GDB waits for the user to answer all
2764 queries. Otherwise, GDB does not wait and assumes the default
2765 answer. When set to auto (the default), GDB determines which
2766 mode to use based on the stdin settings.
2771 For program forks, this is replaced by the new more generic `info
2772 inferiors' command. To list checkpoints, you can still use the
2773 `info checkpoints' command, which was an alias for the `info forks'
2777 Replaced by the new `inferior' command. To switch between
2778 checkpoints, you can still use the `restart' command, which was an
2779 alias for the `fork' command.
2782 This is removed, since some targets don't have a notion of
2783 processes. To switch between processes, you can still use the
2784 `inferior' command using GDB's own inferior number.
2787 For program forks, this is replaced by the new more generic `kill
2788 inferior' command. To delete a checkpoint, you can still use the
2789 `delete checkpoint' command, which was an alias for the `delete
2793 For program forks, this is replaced by the new more generic `detach
2794 inferior' command. To detach a checkpoint, you can still use the
2795 `detach checkpoint' command, which was an alias for the `detach
2798 * New native configurations
2800 x86/x86_64 Darwin i[34567]86-*-darwin*
2802 x86_64 MinGW x86_64-*-mingw*
2806 Lattice Mico32 lm32-*
2807 x86 DICOS i[34567]86-*-dicos*
2808 x86_64 DICOS x86_64-*-dicos*
2811 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2812 (mingw32ce) debugging.
2818 These commands were actually not implemented on any target.
2820 *** Changes in GDB 6.8
2822 * New native configurations
2824 NetBSD/hppa hppa*-*netbsd*
2825 Xtensa GNU/Linux xtensa*-*-linux*
2829 NetBSD/hppa hppa*-*-netbsd*
2830 Xtensa GNU/Lunux xtensa*-*-linux*
2832 * Change in command line behavior -- corefiles vs. process ids.
2834 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2835 attaching to process NUMBER fails, GDB no longer attempts to open a
2836 core file named NUMBER. Attaching to a program using the -c option
2837 is no longer supported. Instead, use the '-p' or '--pid' options.
2839 * GDB can now be built as a native debugger for debugging Windows x86
2840 (mingw32) Portable Executable (PE) programs.
2842 * Pending breakpoints no longer change their number when their address
2845 * GDB now supports breakpoints with multiple locations,
2846 including breakpoints on C++ constructors, inside C++ templates,
2847 and in inlined functions.
2849 * GDB's ability to debug optimized code has been improved. GDB more
2850 accurately identifies function bodies and lexical blocks that occupy
2851 more than one contiguous range of addresses.
2853 * Target descriptions can now describe registers for PowerPC.
2855 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2856 registers on PowerPC targets.
2858 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2859 targets even when the libthread_db library is not available.
2861 * The GDB remote stub, gdbserver, now supports the new file transfer
2862 commands (remote put, remote get, and remote delete).
2864 * The GDB remote stub, gdbserver, now supports run and attach in
2865 extended-remote mode.
2867 * hppa*64*-*-hpux11* target broken
2868 The debugger is unable to start a program and fails with the following
2869 error: "Error trying to get information about dynamic linker".
2870 The gdb-6.7 release is also affected.
2872 * GDB now supports the --enable-targets= configure option to allow
2873 building a single GDB executable that supports multiple remote
2874 target architectures.
2876 * GDB now supports debugging C and C++ programs which use the
2877 Decimal Floating Point extension. In addition, the PowerPC target
2878 now has a set of pseudo-registers to inspect decimal float values
2879 stored in two consecutive float registers.
2881 * The -break-insert MI command can optionally create pending
2884 * Improved support for debugging Ada
2885 Many improvements to the Ada language support have been made. These
2887 - Better support for Ada2005 interface types
2888 - Improved handling of arrays and slices in general
2889 - Better support for Taft-amendment types
2890 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2892 - Improved command completion in Ada
2895 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2900 set print frame-arguments (all|scalars|none)
2901 show print frame-arguments
2902 The value of this variable can be changed to control which argument
2903 values should be printed by the debugger when displaying a frame.
2908 Transfer files to and from a remote target, and delete remote files.
2915 Transfer files to and from a remote target, and delete remote files.
2917 * New remote packets
2924 Open, close, read, write, and delete files on the remote system.
2927 Attach to an existing process on the remote system, in extended-remote
2931 Run a new process on the remote system, in extended-remote mode.
2933 *** Changes in GDB 6.7
2935 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2936 bfd, libiberty and opcodes, as revealed by static analysis donated by
2937 Coverity, Inc. (http://scan.coverity.com).
2939 * When looking up multiply-defined global symbols, GDB will now prefer the
2940 symbol definition in the current shared library if it was built using the
2941 -Bsymbolic linker option.
2943 * When the Text User Interface (TUI) is not configured, GDB will now
2944 recognize the -tui command-line option and print a message that the TUI
2947 * The GDB remote stub, gdbserver, now has lower overhead for high
2948 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2950 * GDB for MIPS targets now autodetects whether a remote target provides
2951 32-bit or 64-bit register values.
2953 * Support for C++ member pointers has been improved.
2955 * GDB now understands XML target descriptions, which specify the
2956 target's overall architecture. GDB can read a description from
2957 a local file or over the remote serial protocol.
2959 * Vectors of single-byte data use a new integer type which is not
2960 automatically displayed as character or string data.
2962 * The /s format now works with the print command. It displays
2963 arrays of single-byte integers and pointers to single-byte integers
2966 * Target descriptions can now describe target-specific registers,
2967 for architectures which have implemented the support (currently
2968 only ARM, M68K, and MIPS).
2970 * GDB and the GDB remote stub, gdbserver, now support the XScale
2973 * The GDB remote stub, gdbserver, has been updated to support
2974 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2975 has been rewritten to use the standard GDB remote protocol.
2977 * GDB can now step into C++ functions which are called through thunks.
2979 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2981 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2982 layout. It also supports a TextSeg= and DataSeg= response when only
2983 segment base addresses (rather than offsets) are available.
2985 * The /i format now outputs any trailing branch delay slot instructions
2986 immediately following the last instruction within the count specified.
2988 * The GDB remote protocol "T" stop reply packet now supports a
2989 "library" response. Combined with the new "qXfer:libraries:read"
2990 packet, this response allows GDB to debug shared libraries on targets
2991 where the operating system manages the list of loaded libraries (e.g.
2992 Windows and SymbianOS).
2994 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2995 (DLLs) on Windows and Windows CE targets.
2997 * GDB now supports a faster verification that a .debug file matches its binary
2998 according to its build-id signature, if the signature is present.
3004 Enable or disable hardware flow control (RTS/CTS) on the serial port
3005 when debugging using remote targets.
3007 set mem inaccessible-by-default
3008 show mem inaccessible-by-default
3009 If the target supplies a memory map, for instance via the remote
3010 protocol's "qXfer:memory-map:read" packet, setting this variable
3011 prevents GDB from accessing memory outside the memory map. This
3012 is useful for targets with memory mapped registers or which react
3013 badly to accesses of unmapped address space.
3015 set breakpoint auto-hw
3016 show breakpoint auto-hw
3017 If the target supplies a memory map, for instance via the remote
3018 protocol's "qXfer:memory-map:read" packet, setting this variable
3019 lets GDB use hardware breakpoints automatically for memory regions
3020 where it can not use software breakpoints. This covers both the
3021 "break" command and internal breakpoints used for other commands
3022 including "next" and "finish".
3025 catch exception unhandled
3026 Stop the program execution when Ada exceptions are raised.
3029 Stop the program execution when an Ada assertion failed.
3033 Set an alternate system root for target files. This is a more
3034 general version of "set solib-absolute-prefix", which is now
3035 an alias to "set sysroot".
3038 Provide extended SPU facility status information. This set of
3039 commands is available only when debugging the Cell/B.E. SPU
3042 * New native configurations
3044 OpenBSD/sh sh*-*openbsd*
3047 unset tdesc filename
3049 Use the specified local file as an XML target description, and do
3050 not query the target for its built-in description.
3054 OpenBSD/sh sh*-*-openbsd*
3055 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3056 Toshiba Media Processor mep-elf
3058 * New remote packets
3061 Ignore the specified signals; pass them directly to the debugged program
3062 without stopping other threads or reporting them to GDB.
3064 qXfer:features:read:
3065 Read an XML target description from the target, which describes its
3070 Read or write contents of an spufs file on the target system. These
3071 packets are available only on the Cell/B.E. SPU architecture.
3073 qXfer:libraries:read:
3074 Report the loaded shared libraries. Combined with new "T" packet
3075 response, this packet allows GDB to debug shared libraries on
3076 targets where the operating system manages the list of loaded
3077 libraries (e.g. Windows and SymbianOS).
3081 Support for these obsolete configurations has been removed.
3089 i[34567]86-*-lynxos*
3090 i[34567]86-*-netware*
3091 i[34567]86-*-sco3.2v5*
3092 i[34567]86-*-sco3.2v4*
3094 i[34567]86-*-sysv4.2*
3097 i[34567]86-*-unixware2*
3098 i[34567]86-*-unixware*
3107 * Other removed features
3114 Various m68k-only ROM monitors.
3121 Various Renesas ROM monitors and debugging interfaces for SH and
3126 Support for a Macraigor serial interface to on-chip debugging.
3127 GDB does not directly support the newer parallel or USB
3132 A debug information format. The predecessor to DWARF 2 and
3133 DWARF 3, which are still supported.
3135 Support for the HP aCC compiler on HP-UX/PA-RISC
3137 SOM-encapsulated symbolic debugging information, automatic
3138 invocation of pxdb, and the aCC custom C++ ABI. This does not
3139 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3140 with aCC can still be debugged on an assembly level.
3142 MIPS ".pdr" sections
3144 A MIPS-specific format used to describe stack frame layout
3145 in debugging information.
3149 GDB could work with an older version of Guile to debug
3150 the interpreter and Scheme programs running in it.
3152 set mips stack-arg-size
3153 set mips saved-gpreg-size
3155 Use "set mips abi" to control parameter passing for MIPS.
3157 *** Changes in GDB 6.6
3162 Cell Broadband Engine SPU spu-elf
3164 * GDB can now be configured as a cross-debugger targeting native Windows
3165 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3166 running on a Windows system over TCP/IP to debug Windows programs.
3168 * The GDB remote stub, gdbserver, has been updated to support Windows and
3169 Cygwin debugging. Both single-threaded and multi-threaded programs are
3172 * The "set trust-readonly-sections" command works again. This command was
3173 broken in GDB 6.3, 6.4, and 6.5.
3175 * The "load" command now supports writing to flash memory, if the remote
3176 stub provides the required support.
3178 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3179 longer requires symbolic debug information (e.g. DWARF-2).
3184 unset substitute-path
3185 show substitute-path
3186 Manage a list of substitution rules that GDB uses to rewrite the name
3187 of the directories where the sources are located. This can be useful
3188 for instance when the sources were moved to a different location
3189 between compilation and debugging.
3193 Print each CLI command as it is executed. Each command is prefixed with
3194 a number of `+' symbols representing the nesting depth.
3195 The source command now has a `-v' option to enable the same feature.
3199 The ARM Demon monitor support (RDP protocol, "target rdp").
3201 Kernel Object Display, an embedded debugging feature which only worked with
3202 an obsolete version of Cisco IOS.
3204 The 'set download-write-size' and 'show download-write-size' commands.
3206 * New remote packets
3209 Tell a stub about GDB client features, and request remote target features.
3210 The first feature implemented is PacketSize, which allows the target to
3211 specify the size of packets it can handle - to minimize the number of
3212 packets required and improve performance when connected to a remote
3216 Fetch an OS auxilliary vector from the remote stub. This packet is a
3217 more efficient replacement for qPart:auxv:read.
3219 qXfer:memory-map:read:
3220 Fetch a memory map from the remote stub, including information about
3221 RAM, ROM, and flash memory devices.
3226 Erase and program a flash memory device.
3228 * Removed remote packets
3231 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3232 used it, and only gdbserver implemented it.
3234 *** Changes in GDB 6.5
3238 Renesas M32C/M16C m32c-elf
3240 Morpho Technologies ms1 ms1-elf
3244 init-if-undefined Initialize a convenience variable, but
3245 only if it doesn't already have a value.
3247 The following commands are presently only implemented for native GNU/Linux:
3249 checkpoint Save a snapshot of the program state.
3251 restart <n> Return the program state to a
3252 previously saved state.
3254 info checkpoints List currently saved checkpoints.
3256 delete-checkpoint <n> Delete a previously saved checkpoint.
3258 set|show detach-on-fork Tell gdb whether to detach from a newly
3259 forked process, or to keep debugging it.
3261 info forks List forks of the user program that
3262 are available to be debugged.
3264 fork <n> Switch to debugging one of several
3265 forks of the user program that are
3266 available to be debugged.
3268 delete-fork <n> Delete a fork from the list of forks
3269 that are available to be debugged (and
3270 kill the forked process).
3272 detach-fork <n> Delete a fork from the list of forks
3273 that are available to be debugged (and
3274 allow the process to continue).
3278 Morpho Technologies ms2 ms1-elf
3280 * Improved Windows host support
3282 GDB now builds as a cross debugger hosted on i686-mingw32, including
3283 native console support, and remote communications using either
3284 network sockets or serial ports.
3286 * Improved Modula-2 language support
3288 GDB can now print most types in the Modula-2 syntax. This includes:
3289 basic types, set types, record types, enumerated types, range types,
3290 pointer types and ARRAY types. Procedure var parameters are correctly
3291 printed and hexadecimal addresses and character constants are also
3292 written in the Modula-2 syntax. Best results can be obtained by using
3293 GNU Modula-2 together with the -gdwarf-2 command line option.
3297 The ARM rdi-share module.
3299 The Netware NLM debug server.
3301 *** Changes in GDB 6.4
3303 * New native configurations
3305 OpenBSD/arm arm*-*-openbsd*
3306 OpenBSD/mips64 mips64-*-openbsd*
3310 Morpho Technologies ms1 ms1-elf
3312 * New command line options
3314 --batch-silent As for --batch, but totally silent.
3315 --return-child-result The debugger will exist with the same value
3316 the child (debugged) program exited with.
3317 --eval-command COMMAND, -ex COMMAND
3318 Execute a single GDB CLI command. This may be
3319 specified multiple times and in conjunction
3320 with the --command (-x) option.
3322 * Deprecated commands removed
3324 The following commands, that were deprecated in 2000, have been
3328 set|show arm disassembly-flavor set|show arm disassembler
3329 othernames set arm disassembler
3330 set|show remotedebug set|show debug remote
3331 set|show archdebug set|show debug arch
3332 set|show eventdebug set|show debug event
3335 * New BSD user-level threads support
3337 It is now possible to debug programs using the user-level threads
3338 library on OpenBSD and FreeBSD. Currently supported (target)
3341 FreeBSD/amd64 x86_64-*-freebsd*
3342 FreeBSD/i386 i386-*-freebsd*
3343 OpenBSD/i386 i386-*-openbsd*
3345 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3346 are not yet supported.
3348 * New support for Matsushita MN10300 w/sim added
3349 (Work in progress). mn10300-elf.
3351 * REMOVED configurations and files
3353 VxWorks and the XDR protocol *-*-vxworks
3354 Motorola MCORE mcore-*-*
3355 National Semiconductor NS32000 ns32k-*-*
3357 * New "set print array-indexes" command
3359 After turning this setting "on", GDB prints the index of each element
3360 when displaying arrays. The default is "off" to preserve the previous
3363 * VAX floating point support
3365 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3367 * User-defined command support
3369 In addition to using $arg0..$arg9 for argument passing, it is now possible
3370 to use $argc to determine now many arguments have been passed. See the
3371 section on user-defined commands in the user manual for more information.
3373 *** Changes in GDB 6.3:
3375 * New command line option
3377 GDB now accepts -l followed by a number to set the timeout for remote
3380 * GDB works with GCC -feliminate-dwarf2-dups
3382 GDB now supports a more compact representation of DWARF-2 debug
3383 information using DW_FORM_ref_addr references. These are produced
3384 by GCC with the option -feliminate-dwarf2-dups and also by some
3385 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3386 to use -feliminate-dwarf2-dups.
3388 * Internationalization
3390 When supported by the host system, GDB will be built with
3391 internationalization (libintl). The task of marking up the sources is
3392 continued, we're looking forward to our first translation.
3396 Initial support for debugging programs compiled with the GNAT
3397 implementation of the Ada programming language has been integrated
3398 into GDB. In this release, support is limited to expression evaluation.
3400 * New native configurations
3402 GNU/Linux/m32r m32r-*-linux-gnu
3406 GDB's remote protocol now includes support for the 'p' packet. This
3407 packet is used to fetch individual registers from a remote inferior.
3409 * END-OF-LIFE registers[] compatibility module
3411 GDB's internal register infrastructure has been completely rewritten.
3412 The new infrastructure making possible the implementation of key new
3413 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3416 GDB 6.3 will be the last release to include the the registers[]
3417 compatibility module that allowed out-of-date configurations to
3418 continue to work. This change directly impacts the following
3428 powerpc bdm protocol
3430 Unless there is activity to revive these configurations, they will be
3431 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3433 * OBSOLETE configurations and files
3435 Configurations that have been declared obsolete in this release have
3436 been commented out. Unless there is activity to revive these
3437 configurations, the next release of GDB will have their sources
3438 permanently REMOVED.
3447 *** Changes in GDB 6.2.1:
3449 * MIPS `break main; run' gave an heuristic-fence-post warning
3451 When attempting to run even a simple program, a warning about
3452 heuristic-fence-post being hit would be reported. This problem has
3455 * MIPS IRIX 'long double' crashed GDB
3457 When examining a long double variable, GDB would get a segmentation
3458 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3459 IRIX long double values).
3463 A bug in the VAX stack code was causing problems with the "next"
3464 command. This problem has been fixed.
3466 *** Changes in GDB 6.2:
3468 * Fix for ``many threads''
3470 On GNU/Linux systems that use the NPTL threads library, a program
3471 rapidly creating and deleting threads would confuse GDB leading to the
3474 ptrace: No such process.
3475 thread_db_get_info: cannot get thread info: generic error
3477 This problem has been fixed.
3479 * "-async" and "-noasync" options removed.
3481 Support for the broken "-noasync" option has been removed (it caused
3484 * New ``start'' command.
3486 This command runs the program until the begining of the main procedure.
3488 * New BSD Kernel Data Access Library (libkvm) interface
3490 Using ``target kvm'' it is now possible to debug kernel core dumps and
3491 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3492 platforms. Currently supported (native-only) configurations are:
3494 FreeBSD/amd64 x86_64-*-freebsd*
3495 FreeBSD/i386 i?86-*-freebsd*
3496 NetBSD/i386 i?86-*-netbsd*
3497 NetBSD/m68k m68*-*-netbsd*
3498 NetBSD/sparc sparc-*-netbsd*
3499 OpenBSD/amd64 x86_64-*-openbsd*
3500 OpenBSD/i386 i?86-*-openbsd*
3501 OpenBSD/m68k m68*-openbsd*
3502 OpenBSD/sparc sparc-*-openbsd*
3504 * Signal trampoline code overhauled
3506 Many generic problems with GDB's signal handling code have been fixed.
3507 These include: backtraces through non-contiguous stacks; recognition
3508 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3509 call; backtrace through a signal trampoline; step into and out of
3510 signal handlers; and single-stepping in the signal trampoline.
3512 Please note that kernel bugs are a limiting factor here. These
3513 features have been shown to work on an s390 GNU/Linux system that
3514 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3516 * Cygwin support for DWARF 2 added.
3518 * New native configurations
3520 GNU/Linux/hppa hppa*-*-linux*
3521 OpenBSD/hppa hppa*-*-openbsd*
3522 OpenBSD/m68k m68*-*-openbsd*
3523 OpenBSD/m88k m88*-*-openbsd*
3524 OpenBSD/powerpc powerpc-*-openbsd*
3525 NetBSD/vax vax-*-netbsd*
3526 OpenBSD/vax vax-*-openbsd*
3528 * END-OF-LIFE frame compatibility module
3530 GDB's internal frame infrastructure has been completely rewritten.
3531 The new infrastructure making it possible to support key new features
3532 including DWARF 2 Call Frame Information. To aid in the task of
3533 migrating old configurations to this new infrastructure, a
3534 compatibility module, that allowed old configurations to continue to
3535 work, was also included.
3537 GDB 6.2 will be the last release to include this frame compatibility
3538 module. This change directly impacts the following configurations:
3548 Unless there is activity to revive these configurations, they will be
3549 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3551 * REMOVED configurations and files
3553 Sun 3, running SunOS 3 m68*-*-sunos3*
3554 Sun 3, running SunOS 4 m68*-*-sunos4*
3555 Sun 2, running SunOS 3 m68000-*-sunos3*
3556 Sun 2, running SunOS 4 m68000-*-sunos4*
3557 Motorola 680x0 running LynxOS m68*-*-lynxos*
3558 AT&T 3b1/Unix pc m68*-att-*
3559 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3560 decstation mips-dec-* mips-little-*
3561 riscos mips-*-riscos* mips-*-sysv*
3562 sonymips mips-sony-*
3563 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3565 *** Changes in GDB 6.1.1:
3567 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3569 The TUI (Text-mode User Interface) is now built as part of a default
3570 GDB configuration. It is enabled by either selecting the TUI with the
3571 command line option "-i=tui" or by running the separate "gdbtui"
3572 program. For more information on the TUI, see the manual "Debugging
3575 * Pending breakpoint support (also included in GDB 6.1)
3577 Support has been added to allow you to specify breakpoints in shared
3578 libraries that have not yet been loaded. If a breakpoint location
3579 cannot be found, and the "breakpoint pending" option is set to auto,
3580 GDB queries you if you wish to make the breakpoint pending on a future
3581 shared-library load. If and when GDB resolves the breakpoint symbol,
3582 the pending breakpoint is removed as one or more regular breakpoints
3585 Pending breakpoints are very useful for GCJ Java debugging.
3587 * Fixed ISO-C build problems
3589 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3590 non ISO-C code that stopped them being built using a more strict ISO-C
3591 compiler (e.g., IBM's C compiler).
3593 * Fixed build problem on IRIX 5
3595 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3596 wasn't able to compile compile on an IRIX 5 system.
3598 * Added execute permission to gdb/gdbserver/configure
3600 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3601 permission. This bug would cause configure to fail on a number of
3602 systems (Solaris, IRIX). Ref: server/519.
3604 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3606 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3607 has been updated to use constant array sizes.
3609 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3611 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3612 its generated DWARF Call Frame Info. This encoding was causing GDB to
3613 panic, that panic has been fixed. Ref: gdb/1628.
3615 * Fixed a problem when examining parameters in shared library code.
3617 When examining parameters in optimized shared library code generated
3618 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3619 not available''. GDB now correctly displays the variable's value.
3621 *** Changes in GDB 6.1:
3623 * Removed --with-mmalloc
3625 Support for the mmalloc memory manager has been removed, as it
3626 conflicted with the internal gdb byte cache.
3628 * Changes in AMD64 configurations
3630 The AMD64 target now includes the %cs and %ss registers. As a result
3631 the AMD64 remote protocol has changed; this affects the floating-point
3632 and SSE registers. If you rely on those registers for your debugging,
3633 you should upgrade gdbserver on the remote side.
3635 * Revised SPARC target
3637 The SPARC target has been completely revised, incorporating the
3638 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3639 support for LynxOS and SunOS 4 has been dropped. Calling functions
3640 from within GDB on operating systems with a non-executable stack
3641 (Solaris, OpenBSD) now works.
3645 GDB has a new C++ demangler which does a better job on the mangled
3646 names generated by current versions of g++. It also runs faster, so
3647 with this and other changes gdb should now start faster on large C++
3650 * DWARF 2 Location Expressions
3652 GDB support for location expressions has been extended to support function
3653 arguments and frame bases. Older versions of GDB could crash when they
3656 * C++ nested types and namespaces
3658 GDB's support for nested types and namespaces in C++ has been
3659 improved, especially if you use the DWARF 2 debugging format. (This
3660 is the default for recent versions of GCC on most platforms.)
3661 Specifically, if you have a class "Inner" defined within a class or
3662 namespace "Outer", then GDB realizes that the class's name is
3663 "Outer::Inner", not simply "Inner". This should greatly reduce the
3664 frequency of complaints about not finding RTTI symbols. In addition,
3665 if you are stopped at inside of a function defined within a namespace,
3666 GDB modifies its name lookup accordingly.
3668 * New native configurations
3670 NetBSD/amd64 x86_64-*-netbsd*
3671 OpenBSD/amd64 x86_64-*-openbsd*
3672 OpenBSD/alpha alpha*-*-openbsd*
3673 OpenBSD/sparc sparc-*-openbsd*
3674 OpenBSD/sparc64 sparc64-*-openbsd*
3676 * New debugging protocols
3678 M32R with SDI protocol m32r-*-elf*
3680 * "set prompt-escape-char" command deleted.
3682 The command "set prompt-escape-char" has been deleted. This command,
3683 and its very obscure effet on GDB's prompt, was never documented,
3684 tested, nor mentioned in the NEWS file.
3686 * OBSOLETE configurations and files
3688 Configurations that have been declared obsolete in this release have
3689 been commented out. Unless there is activity to revive these
3690 configurations, the next release of GDB will have their sources
3691 permanently REMOVED.
3693 Sun 3, running SunOS 3 m68*-*-sunos3*
3694 Sun 3, running SunOS 4 m68*-*-sunos4*
3695 Sun 2, running SunOS 3 m68000-*-sunos3*
3696 Sun 2, running SunOS 4 m68000-*-sunos4*
3697 Motorola 680x0 running LynxOS m68*-*-lynxos*
3698 AT&T 3b1/Unix pc m68*-att-*
3699 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3700 decstation mips-dec-* mips-little-*
3701 riscos mips-*-riscos* mips-*-sysv*
3702 sonymips mips-sony-*
3703 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3705 * REMOVED configurations and files
3707 SGI Irix-4.x mips-sgi-irix4 or iris4
3708 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3709 Z8000 simulator z8k-zilog-none or z8ksim
3710 Matsushita MN10200 w/simulator mn10200-*-*
3711 H8/500 simulator h8500-hitachi-hms or h8500hms
3712 HP/PA running BSD hppa*-*-bsd*
3713 HP/PA running OSF/1 hppa*-*-osf*
3714 HP/PA Pro target hppa*-*-pro*
3715 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3716 386BSD i[3456]86-*-bsd*
3717 Sequent family i[3456]86-sequent-sysv4*
3718 i[3456]86-sequent-sysv*
3719 i[3456]86-sequent-bsd*
3720 SPARC running LynxOS sparc-*-lynxos*
3721 SPARC running SunOS 4 sparc-*-sunos4*
3722 Tsqware Sparclet sparclet-*-*
3723 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3725 *** Changes in GDB 6.0:
3729 Support for debugging the Objective-C programming language has been
3730 integrated into GDB.
3732 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3734 DWARF 2's Call Frame Information makes available compiler generated
3735 information that more exactly describes the program's run-time stack.
3736 By using this information, GDB is able to provide more robust stack
3739 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3740 have been updated to use a new backtrace mechanism which includes
3741 DWARF 2 CFI support.
3745 GDB's remote protocol has been extended to include support for hosted
3746 file I/O (where the remote target uses GDB's file system). See GDB's
3747 remote protocol documentation for details.
3749 * All targets using the new architecture framework.
3751 All of GDB's targets have been updated to use the new internal
3752 architecture framework. The way is now open for future GDB releases
3753 to include cross-architecture native debugging support (i386 on amd64,
3756 * GNU/Linux's Thread Local Storage (TLS)
3758 GDB now includes support for for the GNU/Linux implementation of
3759 per-thread variables.
3761 * GNU/Linux's Native POSIX Thread Library (NPTL)
3763 GDB's thread code has been updated to work with either the new
3764 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3766 * Separate debug info.
3768 GDB, in conjunction with BINUTILS, now supports a mechanism for
3769 automatically loading debug information from a separate file. Instead
3770 of shipping full debug and non-debug versions of system libraries,
3771 system integrators can now instead ship just the stripped libraries
3772 and optional debug files.
3774 * DWARF 2 Location Expressions
3776 DWARF 2 Location Expressions allow the compiler to more completely
3777 describe the location of variables (even in optimized code) to the
3780 GDB now includes preliminary support for location expressions (support
3781 for DW_OP_piece is still missing).
3785 A number of long standing bugs that caused GDB to die while starting a
3786 Java application have been fixed. GDB's Java support is now
3787 considered "useable".
3789 * GNU/Linux support for fork, vfork, and exec.
3791 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3792 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3795 * GDB supports logging output to a file
3797 There are two new commands, "set logging" and "show logging", which can be
3798 used to capture GDB's output to a file.
3800 * The meaning of "detach" has changed for gdbserver
3802 The "detach" command will now resume the application, as documented. To
3803 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3806 * d10v, m68hc11 `regs' command deprecated
3808 The `info registers' command has been updated so that it displays the
3809 registers using a format identical to the old `regs' command.
3813 A new command, "maint set profile on/off", has been added. This command can
3814 be used to enable or disable profiling while running GDB, to profile a
3815 session or a set of commands. In addition there is a new configure switch,
3816 "--enable-profiling", which will cause GDB to be compiled with profiling
3817 data, for more informative profiling results.
3819 * Default MI syntax changed to "mi2".
3821 The default MI (machine interface) syntax, enabled by the command line
3822 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3823 "mi1", can be enabled by specifying the option "-i=mi1".
3825 Support for the original "mi0" syntax (included in GDB 5.0) has been
3828 Fix for gdb/192: removed extraneous space when displaying frame level.
3829 Fix for gdb/672: update changelist is now output in mi list format.
3830 Fix for gdb/702: a -var-assign that updates the value now shows up
3831 in a subsequent -var-update.
3833 * New native configurations.
3835 FreeBSD/amd64 x86_64-*-freebsd*
3837 * Multi-arched targets.
3839 HP/PA HPUX11 hppa*-*-hpux*
3840 Renesas M32R/D w/simulator m32r-*-elf*
3842 * OBSOLETE configurations and files
3844 Configurations that have been declared obsolete in this release have
3845 been commented out. Unless there is activity to revive these
3846 configurations, the next release of GDB will have their sources
3847 permanently REMOVED.
3849 Z8000 simulator z8k-zilog-none or z8ksim
3850 Matsushita MN10200 w/simulator mn10200-*-*
3851 H8/500 simulator h8500-hitachi-hms or h8500hms
3852 HP/PA running BSD hppa*-*-bsd*
3853 HP/PA running OSF/1 hppa*-*-osf*
3854 HP/PA Pro target hppa*-*-pro*
3855 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3856 Sequent family i[3456]86-sequent-sysv4*
3857 i[3456]86-sequent-sysv*
3858 i[3456]86-sequent-bsd*
3859 Tsqware Sparclet sparclet-*-*
3860 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3862 * REMOVED configurations and files
3865 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3866 IBM AIX PS/2 i[3456]86-*-aix
3867 i386 running Mach 3.0 i[3456]86-*-mach3*
3868 i386 running Mach i[3456]86-*-mach*
3869 i386 running OSF/1 i[3456]86-*osf1mk*
3870 HP/Apollo 68k Family m68*-apollo*-sysv*,
3872 m68*-hp-bsd*, m68*-hp-hpux*
3873 Argonaut Risc Chip (ARC) arc-*-*
3874 Mitsubishi D30V d30v-*-*
3875 Fujitsu FR30 fr30-*-elf*
3876 OS/9000 i[34]86-*-os9k
3877 I960 with MON960 i960-*-coff
3879 * MIPS $fp behavior changed
3881 The convenience variable $fp, for the MIPS, now consistently returns
3882 the address of the current frame's base. Previously, depending on the
3883 context, $fp could refer to either $sp or the current frame's base
3884 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3885 The GNU Source-Level Debugger''.
3887 *** Changes in GDB 5.3:
3889 * GNU/Linux shared library multi-threaded performance improved.
3891 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3892 `/proc', in preference to `ptrace' for memory reads. This may result
3893 in an improvement in the start-up time of multi-threaded, shared
3894 library applications when run under GDB. One GDB user writes: ``loads
3895 shared libs like mad''.
3897 * ``gdbserver'' now supports multi-threaded applications on some targets
3899 Support for debugging multi-threaded applications which use
3900 the GNU/Linux LinuxThreads package has been added for
3901 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3902 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3904 * GDB now supports C/C++ preprocessor macros.
3906 GDB now expands preprocessor macro invocations in C/C++ expressions,
3907 and provides various commands for showing macro definitions and how
3910 The new command `macro expand EXPRESSION' expands any macro
3911 invocations in expression, and shows the result.
3913 The new command `show macro MACRO-NAME' shows the definition of the
3914 macro named MACRO-NAME, and where it was defined.
3916 Most compilers don't include information about macros in the debugging
3917 information by default. In GCC 3.1, for example, you need to compile
3918 your program with the options `-gdwarf-2 -g3'. If the macro
3919 information is present in the executable, GDB will read it.
3921 * Multi-arched targets.
3923 DEC Alpha (partial) alpha*-*-*
3924 DEC VAX (partial) vax-*-*
3926 National Semiconductor NS32000 (partial) ns32k-*-*
3927 Motorola 68000 (partial) m68k-*-*
3928 Motorola MCORE mcore-*-*
3932 Fujitsu FRV architecture added by Red Hat frv*-*-*
3935 * New native configurations
3937 Alpha NetBSD alpha*-*-netbsd*
3938 SH NetBSD sh*-*-netbsdelf*
3939 MIPS NetBSD mips*-*-netbsd*
3940 UltraSPARC NetBSD sparc64-*-netbsd*
3942 * OBSOLETE configurations and files
3944 Configurations that have been declared obsolete in this release have
3945 been commented out. Unless there is activity to revive these
3946 configurations, the next release of GDB will have their sources
3947 permanently REMOVED.
3949 Mitsubishi D30V d30v-*-*
3950 OS/9000 i[34]86-*-os9k
3951 IBM AIX PS/2 i[3456]86-*-aix
3952 Fujitsu FR30 fr30-*-elf*
3953 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3954 Argonaut Risc Chip (ARC) arc-*-*
3955 i386 running Mach 3.0 i[3456]86-*-mach3*
3956 i386 running Mach i[3456]86-*-mach*
3957 i386 running OSF/1 i[3456]86-*osf1mk*
3958 HP/Apollo 68k Family m68*-apollo*-sysv*,
3960 m68*-hp-bsd*, m68*-hp-hpux*
3961 I960 with MON960 i960-*-coff
3963 * OBSOLETE languages
3965 CHILL, a Pascal like language used by telecommunications companies.
3967 * REMOVED configurations and files
3969 AMD 29k family via UDI a29k-amd-udi, udi29k
3970 A29K VxWorks a29k-*-vxworks
3971 AMD 29000 embedded, using EBMON a29k-none-none
3972 AMD 29000 embedded with COFF a29k-none-coff
3973 AMD 29000 embedded with a.out a29k-none-aout
3975 testsuite/gdb.hp/gdb.threads-hp/ directory
3977 * New command "set max-user-call-depth <nnn>"
3979 This command allows the user to limit the call depth of user-defined
3980 commands. The default is 1024.
3982 * Changes in FreeBSD/i386 native debugging.
3984 Support for the "generate-core-file" has been added.
3986 * New commands "dump", "append", and "restore".
3988 These commands allow data to be copied from target memory
3989 to a bfd-format or binary file (dump and append), and back
3990 from a file into memory (restore).
3992 * Improved "next/step" support on multi-processor Alpha Tru64.
3994 The previous single-step mechanism could cause unpredictable problems,
3995 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3996 of a software single-step mechanism prevents this.
3998 *** Changes in GDB 5.2.1:
4006 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4007 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4008 Fix, by Joel Brobecker imported from mainline.
4010 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4011 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4012 Fix, by Fred Fish, imported from mainline.
4014 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4015 Surprisingly enough, it works now.
4016 By Michal Ludvig, imported from mainline.
4018 i386 hardware watchpoint support:
4019 avoid misses on second run for some targets.
4020 By Pierre Muller, imported from mainline.
4022 *** Changes in GDB 5.2:
4024 * New command "set trust-readonly-sections on[off]".
4026 This command is a hint that tells gdb that read-only sections
4027 really are read-only (ie. that their contents will not change).
4028 In this mode, gdb will go to the object file rather than the
4029 target to read memory from read-only sections (such as ".text").
4030 This can be a significant performance improvement on some
4031 (notably embedded) targets.
4033 * New command "generate-core-file" (or "gcore").
4035 This new gdb command allows the user to drop a core file of the child
4036 process state at any time. So far it's been implemented only for
4037 GNU/Linux and Solaris, but should be relatively easily ported to other
4038 hosts. Argument is core file name (defaults to core.<pid>).
4040 * New command line option
4042 GDB now accepts --pid or -p followed by a process id.
4044 * Change in command line behavior -- corefiles vs. process ids.
4046 There is a subtle behavior in the way in which GDB handles
4047 command line arguments. The first non-flag argument is always
4048 a program to debug, but the second non-flag argument may either
4049 be a corefile or a process id. Previously, GDB would attempt to
4050 open the second argument as a corefile, and if that failed, would
4051 issue a superfluous error message and then attempt to attach it as
4052 a process. Now, if the second argument begins with a non-digit,
4053 it will be treated as a corefile. If it begins with a digit,
4054 GDB will attempt to attach it as a process, and if no such process
4055 is found, will then attempt to open it as a corefile.
4057 * Changes in ARM configurations.
4059 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4060 configuration is fully multi-arch.
4062 * New native configurations
4064 ARM NetBSD arm*-*-netbsd*
4065 x86 OpenBSD i[3456]86-*-openbsd*
4066 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4067 Sparc64 running FreeBSD sparc64-*-freebsd*
4071 Sanyo XStormy16 xstormy16-elf
4073 * OBSOLETE configurations and files
4075 Configurations that have been declared obsolete in this release have
4076 been commented out. Unless there is activity to revive these
4077 configurations, the next release of GDB will have their sources
4078 permanently REMOVED.
4080 AMD 29k family via UDI a29k-amd-udi, udi29k
4081 A29K VxWorks a29k-*-vxworks
4082 AMD 29000 embedded, using EBMON a29k-none-none
4083 AMD 29000 embedded with COFF a29k-none-coff
4084 AMD 29000 embedded with a.out a29k-none-aout
4086 testsuite/gdb.hp/gdb.threads-hp/ directory
4088 * REMOVED configurations and files
4090 TI TMS320C80 tic80-*-*
4092 PowerPC Solaris powerpcle-*-solaris*
4093 PowerPC Windows NT powerpcle-*-cygwin32
4094 PowerPC Netware powerpc-*-netware*
4095 Harris/CXUX m88k m88*-harris-cxux*
4096 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4097 ns32k-utek-sysv* ns32k-utek-*
4098 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4099 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4100 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4101 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4102 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4104 * Changes to command line processing
4106 The new `--args' feature can be used to specify command-line arguments
4107 for the inferior from gdb's command line.
4109 * Changes to key bindings
4111 There is a new `operate-and-get-next' function bound to `C-o'.
4113 *** Changes in GDB 5.1.1
4115 Fix compile problem on DJGPP.
4117 Fix a problem with floating-point registers on the i386 being
4120 Fix to stop GDB crashing on .debug_str debug info.
4122 Numerous documentation fixes.
4124 Numerous testsuite fixes.
4126 *** Changes in GDB 5.1:
4128 * New native configurations
4130 Alpha FreeBSD alpha*-*-freebsd*
4131 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4132 MIPS GNU/Linux mips*-*-linux*
4133 MIPS SGI Irix 6.x mips*-sgi-irix6*
4134 ia64 AIX ia64-*-aix*
4135 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4139 Motorola 68HC11 and 68HC12 m68hc11-elf
4141 UltraSparc running GNU/Linux sparc64-*-linux*
4143 * OBSOLETE configurations and files
4145 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4146 Harris/CXUX m88k m88*-harris-cxux*
4147 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4148 ns32k-utek-sysv* ns32k-utek-*
4149 TI TMS320C80 tic80-*-*
4151 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4152 PowerPC Solaris powerpcle-*-solaris*
4153 PowerPC Windows NT powerpcle-*-cygwin32
4154 PowerPC Netware powerpc-*-netware*
4155 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4156 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4157 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4158 Apple Macintosh (MPW) host N/A
4160 stuff.c (Program to stuff files into a specially prepared space in kdb)
4161 kdb-start.c (Main loop for the standalone kernel debugger)
4163 Configurations that have been declared obsolete in this release have
4164 been commented out. Unless there is activity to revive these
4165 configurations, the next release of GDB will have their sources
4166 permanently REMOVED.
4168 * REMOVED configurations and files
4170 Altos 3068 m68*-altos-*
4171 Convex c1-*-*, c2-*-*
4173 ARM RISCix arm-*-* (as host)
4177 * GDB has been converted to ISO C.
4179 GDB's source code has been converted to ISO C. In particular, the
4180 sources are fully protoized, and rely on standard headers being
4185 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4187 * The MI enabled by default.
4189 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4190 revised and enabled by default. Packages which use GDB as a debugging
4191 engine behind a UI or another front end are encouraged to switch to
4192 using the GDB/MI interface, instead of the old annotations interface
4193 which is now deprecated.
4195 * Support for debugging Pascal programs.
4197 GDB now includes support for debugging Pascal programs. The following
4198 main features are supported:
4200 - Pascal-specific data types such as sets;
4202 - automatic recognition of Pascal sources based on file-name
4205 - Pascal-style display of data types, variables, and functions;
4207 - a Pascal expression parser.
4209 However, some important features are not yet supported.
4211 - Pascal string operations are not supported at all;
4213 - there are some problems with boolean types;
4215 - Pascal type hexadecimal constants are not supported
4216 because they conflict with the internal variables format;
4218 - support for Pascal objects and classes is not full yet;
4220 - unlike Pascal, GDB is case-sensitive for symbol names.
4222 * Changes in completion.
4224 Commands such as `shell', `run' and `set args', which pass arguments
4225 to inferior programs, now complete on file names, similar to what
4226 users expect at the shell prompt.
4228 Commands which accept locations, such as `disassemble', `print',
4229 `breakpoint', `until', etc. now complete on filenames as well as
4230 program symbols. Thus, if you type "break foob TAB", and the source
4231 files linked into the programs include `foobar.c', that file name will
4232 be one of the candidates for completion. However, file names are not
4233 considered for completion after you typed a colon that delimits a file
4234 name from a name of a function in that file, as in "break foo.c:bar".
4236 `set demangle-style' completes on available demangling styles.
4238 * New platform-independent commands:
4240 It is now possible to define a post-hook for a command as well as a
4241 hook that runs before the command. For more details, see the
4242 documentation of `hookpost' in the GDB manual.
4244 * Changes in GNU/Linux native debugging.
4246 Support for debugging multi-threaded programs has been completely
4247 revised for all platforms except m68k and sparc. You can now debug as
4248 many threads as your system allows you to have.
4250 Attach/detach is supported for multi-threaded programs.
4252 Support for SSE registers was added for x86. This doesn't work for
4253 multi-threaded programs though.
4255 * Changes in MIPS configurations.
4257 Multi-arch support is enabled for all MIPS configurations.
4259 GDB can now be built as native debugger on SGI Irix 6.x systems for
4260 debugging n32 executables. (Debugging 64-bit executables is not yet
4263 * Unified support for hardware watchpoints in all x86 configurations.
4265 Most (if not all) native x86 configurations support hardware-assisted
4266 breakpoints and watchpoints in a unified manner. This support
4267 implements debug register sharing between watchpoints, which allows to
4268 put a virtually infinite number of watchpoints on the same address,
4269 and also supports watching regions up to 16 bytes with several debug
4272 The new maintenance command `maintenance show-debug-regs' toggles
4273 debugging print-outs in functions that insert, remove, and test
4274 watchpoints and hardware breakpoints.
4276 * Changes in the DJGPP native configuration.
4278 New command ``info dos sysinfo'' displays assorted information about
4279 the CPU, OS, memory, and DPMI server.
4281 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4282 display information about segment descriptors stored in GDT, LDT, and
4285 New commands ``info dos pde'' and ``info dos pte'' display entries
4286 from Page Directory and Page Tables (for now works with CWSDPMI only).
4287 New command ``info dos address-pte'' displays the Page Table entry for
4288 a given linear address.
4290 GDB can now pass command lines longer than 126 characters to the
4291 program being debugged (requires an update to the libdbg.a library
4292 which is part of the DJGPP development kit).
4294 DWARF2 debug info is now supported.
4296 It is now possible to `step' and `next' through calls to `longjmp'.
4298 * Changes in documentation.
4300 All GDB documentation was converted to GFDL, the GNU Free
4301 Documentation License.
4303 Tracepoints-related commands are now fully documented in the GDB
4306 TUI, the Text-mode User Interface, is now documented in the manual.
4308 Tracepoints-related commands are now fully documented in the GDB
4311 The "GDB Internals" manual now has an index. It also includes
4312 documentation of `ui_out' functions, GDB coding standards, x86
4313 hardware watchpoints, and memory region attributes.
4315 * GDB's version number moved to ``version.in''
4317 The Makefile variable VERSION has been replaced by the file
4318 ``version.in''. People creating GDB distributions should update the
4319 contents of this file.
4323 GUD support is now a standard part of the EMACS distribution.
4325 *** Changes in GDB 5.0:
4327 * Improved support for debugging FP programs on x86 targets
4329 Unified and much-improved support for debugging floating-point
4330 programs on all x86 targets. In particular, ``info float'' now
4331 displays the FP registers in the same format on all x86 targets, with
4332 greater level of detail.
4334 * Improvements and bugfixes in hardware-assisted watchpoints
4336 It is now possible to watch array elements, struct members, and
4337 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4338 on x86 targets no longer erroneously trigger when the address is
4341 * Improvements in the native DJGPP version of GDB
4343 The distribution now includes all the scripts and auxiliary files
4344 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4345 machines ``out of the box''.
4347 The DJGPP version can now debug programs that use signals. It is
4348 possible to catch signals that happened in the debuggee, deliver
4349 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4350 would kill the program being debugged.) Programs that hook hardware
4351 interrupts (keyboard, timer, etc.) can also be debugged.
4353 It is now possible to debug DJGPP programs that redirect their
4354 standard handles or switch them to raw (as opposed to cooked) mode, or
4355 even close them. The command ``run < foo > bar'' works as expected,
4356 and ``info terminal'' reports useful information about the debuggee's
4357 terminal, including raw/cooked mode, redirection, etc.
4359 The DJGPP version now uses termios functions for console I/O, which
4360 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4363 DOS-style file names with drive letters are now fully supported by
4366 It is now possible to debug DJGPP programs that switch their working
4367 directory. It is also possible to rerun the debuggee any number of
4368 times without restarting GDB; thus, you can use the same setup,
4369 breakpoints, etc. for many debugging sessions.
4371 * New native configurations
4373 ARM GNU/Linux arm*-*-linux*
4374 PowerPC GNU/Linux powerpc-*-linux*
4378 Motorola MCore mcore-*-*
4379 x86 VxWorks i[3456]86-*-vxworks*
4380 PowerPC VxWorks powerpc-*-vxworks*
4381 TI TMS320C80 tic80-*-*
4383 * OBSOLETE configurations
4385 Altos 3068 m68*-altos-*
4386 Convex c1-*-*, c2-*-*
4388 ARM RISCix arm-*-* (as host)
4391 Configurations that have been declared obsolete will be commented out,
4392 but the code will be left in place. If there is no activity to revive
4393 these configurations before the next release of GDB, the sources will
4394 be permanently REMOVED.
4396 * Gould support removed
4398 Support for the Gould PowerNode and NP1 has been removed.
4400 * New features for SVR4
4402 On SVR4 native platforms (such as Solaris), if you attach to a process
4403 without first loading a symbol file, GDB will now attempt to locate and
4404 load symbols from the running process's executable file.
4406 * Many C++ enhancements
4408 C++ support has been greatly improved. Overload resolution now works properly
4409 in almost all cases. RTTI support is on the way.
4411 * Remote targets can connect to a sub-program
4413 A popen(3) style serial-device has been added. This device starts a
4414 sub-process (such as a stand-alone simulator) and then communicates
4415 with that. The sub-program to run is specified using the syntax
4416 ``|<program> <args>'' vis:
4418 (gdb) set remotedebug 1
4419 (gdb) target extended-remote |mn10300-elf-sim program-args
4421 * MIPS 64 remote protocol
4423 A long standing bug in the mips64 remote protocol where by GDB
4424 expected certain 32 bit registers (ex SR) to be transfered as 32
4425 instead of 64 bits has been fixed.
4427 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4428 added to provide backward compatibility with older versions of GDB.
4430 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4432 The command ``set remotebinarydownload'' command has been replaced by
4433 ``set remote X-packet''. Other commands in ``set remote'' family
4434 include ``set remote P-packet''.
4436 * Breakpoint commands accept ranges.
4438 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4439 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4440 ``tracepoint passcount'' also accepts a range of tracepoints.
4442 * ``apropos'' command added.
4444 The ``apropos'' command searches through command names and
4445 documentation strings, printing out matches, making it much easier to
4446 try to find a command that does what you are looking for.
4450 A new machine oriented interface (MI) has been added to GDB. This
4451 interface is designed for debug environments running GDB as a separate
4452 process. This is part of the long term libGDB project. See the
4453 "GDB/MI" chapter of the GDB manual for further information. It can be
4454 enabled by configuring with:
4456 .../configure --enable-gdbmi
4458 *** Changes in GDB-4.18:
4460 * New native configurations
4462 HP-UX 10.20 hppa*-*-hpux10.20
4463 HP-UX 11.x hppa*-*-hpux11.0*
4464 M68K GNU/Linux m68*-*-linux*
4468 Fujitsu FR30 fr30-*-elf*
4469 Intel StrongARM strongarm-*-*
4470 Mitsubishi D30V d30v-*-*
4472 * OBSOLETE configurations
4474 Gould PowerNode, NP1 np1-*-*, pn-*-*
4476 Configurations that have been declared obsolete will be commented out,
4477 but the code will be left in place. If there is no activity to revive
4478 these configurations before the next release of GDB, the sources will
4479 be permanently REMOVED.
4483 As a compatibility experiment, GDB's source files buildsym.h and
4484 buildsym.c have been converted to pure standard C, no longer
4485 containing any K&R compatibility code. We believe that all systems in
4486 use today either come with a standard C compiler, or have a GCC port
4487 available. If this is not true, please report the affected
4488 configuration to bug-gdb@gnu.org immediately. See the README file for
4489 information about getting a standard C compiler if you don't have one
4494 GDB now uses readline 2.2.
4496 * set extension-language
4498 You can now control the mapping between filename extensions and source
4499 languages by using the `set extension-language' command. For instance,
4500 you can ask GDB to treat .c files as C++ by saying
4501 set extension-language .c c++
4502 The command `info extensions' lists all of the recognized extensions
4503 and their associated languages.
4505 * Setting processor type for PowerPC and RS/6000
4507 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4508 you can use the `set processor' command to specify what variant of the
4509 PowerPC family you are debugging. The command
4513 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4514 following PowerPC and RS6000 variants:
4516 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4517 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4519 403GC IBM PowerPC 403GC
4520 505 Motorola PowerPC 505
4521 860 Motorola PowerPC 860 or 850
4522 601 Motorola PowerPC 601
4523 602 Motorola PowerPC 602
4524 603 Motorola/IBM PowerPC 603 or 603e
4525 604 Motorola PowerPC 604 or 604e
4526 750 Motorola/IBM PowerPC 750 or 750
4528 At the moment, this command just tells GDB what to name the
4529 special-purpose processor registers. Since almost all the affected
4530 registers are inaccessible to user-level programs, this command is
4531 only useful for remote debugging in its present form.
4535 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4536 more extensive support for HP-UX. Added features include shared
4537 library support, kernel threads and hardware watchpoints for 11.00,
4538 support for HP's ANSI C and C++ compilers, and a compatibility mode
4539 for xdb and dbx commands.
4543 HP's donation includes the new concept of catchpoints, which is a
4544 generalization of the old catch command. On HP-UX, it is now possible
4545 to catch exec, fork, and vfork, as well as library loading.
4547 This means that the existing catch command has changed; its first
4548 argument now specifies the type of catch to be set up. See the
4549 output of "help catch" for a list of catchpoint types.
4551 * Debugging across forks
4553 On HP-UX, you can choose which process to debug when a fork() happens
4558 HP has donated a curses-based terminal user interface (TUI). To get
4559 it, build with --enable-tui. Although this can be enabled for any
4560 configuration, at present it only works for native HP debugging.
4562 * GDB remote protocol additions
4564 A new protocol packet 'X' that writes binary data is now available.
4565 Default behavior is to try 'X', then drop back to 'M' if the stub
4566 fails to respond. The settable variable `remotebinarydownload'
4567 allows explicit control over the use of 'X'.
4569 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4570 full 64-bit address. The command
4572 set remoteaddresssize 32
4574 can be used to revert to the old behaviour. For existing remote stubs
4575 the change should not be noticed, as the additional address information
4578 In order to assist in debugging stubs, you may use the maintenance
4579 command `packet' to send any text string to the stub. For instance,
4581 maint packet heythere
4583 sends the packet "$heythere#<checksum>". Note that it is very easy to
4584 disrupt a debugging session by sending the wrong packet at the wrong
4587 The compare-sections command allows you to compare section data on the
4588 target to what is in the executable file without uploading or
4589 downloading, by comparing CRC checksums.
4591 * Tracing can collect general expressions
4593 You may now collect general expressions at tracepoints. This requires
4594 further additions to the target-side stub; see tracepoint.c and
4595 doc/agentexpr.texi for further details.
4597 * mask-address variable for Mips
4599 For Mips targets, you may control the zeroing of the upper 32 bits of
4600 a 64-bit address by entering `set mask-address on'. This is mainly
4601 of interest to users of embedded R4xxx and R5xxx processors.
4603 * Higher serial baud rates
4605 GDB's serial code now allows you to specify baud rates 57600, 115200,
4606 230400, and 460800 baud. (Note that your host system may not be able
4607 to achieve all of these rates.)
4611 The i960 configuration now includes an initial implementation of a
4612 builtin simulator, contributed by Jim Wilson.
4615 *** Changes in GDB-4.17:
4617 * New native configurations
4619 Alpha GNU/Linux alpha*-*-linux*
4620 Unixware 2.x i[3456]86-unixware2*
4621 Irix 6.x mips*-sgi-irix6*
4622 PowerPC GNU/Linux powerpc-*-linux*
4623 PowerPC Solaris powerpcle-*-solaris*
4624 Sparc GNU/Linux sparc-*-linux*
4625 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4629 Argonaut Risc Chip (ARC) arc-*-*
4630 Hitachi H8/300S h8300*-*-*
4631 Matsushita MN10200 w/simulator mn10200-*-*
4632 Matsushita MN10300 w/simulator mn10300-*-*
4633 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4634 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4635 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4636 Mitsubishi D10V w/simulator d10v-*-*
4637 Mitsubishi M32R/D w/simulator m32r-*-elf*
4638 Tsqware Sparclet sparclet-*-*
4639 NEC V850 w/simulator v850-*-*
4641 * New debugging protocols
4643 ARM with RDI protocol arm*-*-*
4644 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4645 DDB and LSI variants of PMON protocol mips*-*-*
4646 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4647 PowerPC with SDS protocol powerpc{,le}-*-eabi
4648 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4652 All configurations can now understand and use the DWARF 2 debugging
4653 format. The choice is automatic, if the symbol file contains DWARF 2
4658 GDB now includes basic Java language support. This support is
4659 only useful with Java compilers that produce native machine code.
4661 * solib-absolute-prefix and solib-search-path
4663 For SunOS and SVR4 shared libraries, you may now set the prefix for
4664 loading absolute shared library symbol files, and the search path for
4665 locating non-absolute shared library symbol files.
4667 * Live range splitting
4669 GDB can now effectively debug code for which GCC has performed live
4670 range splitting as part of its optimization. See gdb/doc/LRS for
4671 more details on the expected format of the stabs information.
4675 GDB's support for the GNU Hurd, including thread debugging, has been
4676 updated to work with current versions of the Hurd.
4680 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4681 instruction set. ARM GDB automatically detects when Thumb
4682 instructions are in use, and adjusts disassembly and backtracing
4687 GDB's MIPS target configurations now handle the MIP16 16-bit
4692 GDB now includes support for overlays; if an executable has been
4693 linked such that multiple sections are based at the same address, GDB
4694 will decide which section to use for symbolic info. You can choose to
4695 control the decision manually, using overlay commands, or implement
4696 additional target-side support and use "overlay load-target" to bring
4697 in the overlay mapping. Do "help overlay" for more detail.
4701 The command "info symbol <address>" displays information about
4702 the symbol at the specified address.
4706 The standard remote protocol now includes an extension that allows
4707 asynchronous collection and display of trace data. This requires
4708 extensive support in the target-side debugging stub. Tracing mode
4709 includes a new interaction mode in GDB and new commands: see the
4710 file tracepoint.c for more details.
4714 Configurations for embedded MIPS now include a simulator contributed
4715 by Cygnus Solutions. The simulator supports the instruction sets
4716 of most MIPS variants.
4720 Sparc configurations may now include the ERC32 simulator contributed
4721 by the European Space Agency. The simulator is not built into
4722 Sparc targets by default; configure with --enable-sim to include it.
4726 For target configurations that may include multiple variants of a
4727 basic architecture (such as MIPS and SH), you may now set the
4728 architecture explicitly. "set arch" sets, "info arch" lists
4729 the possible architectures.
4731 *** Changes in GDB-4.16:
4733 * New native configurations
4735 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4736 M68K NetBSD m68k-*-netbsd*
4737 PowerPC AIX 4.x powerpc-*-aix*
4738 PowerPC MacOS powerpc-*-macos*
4739 PowerPC Windows NT powerpcle-*-cygwin32
4740 RS/6000 AIX 4.x rs6000-*-aix4*
4744 ARM with RDP protocol arm-*-*
4745 I960 with MON960 i960-*-coff
4746 MIPS VxWorks mips*-*-vxworks*
4747 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4748 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4750 Matra Sparclet sparclet-*-*
4754 The powerpc-eabi configuration now includes the PSIM simulator,
4755 contributed by Andrew Cagney, with assistance from Mike Meissner.
4756 PSIM is a very elaborate model of the PowerPC, including not only
4757 basic instruction set execution, but also details of execution unit
4758 performance and I/O hardware. See sim/ppc/README for more details.
4762 GDB now works with Solaris 2.5.
4764 * Windows 95/NT native
4766 GDB will now work as a native debugger on Windows 95 and Windows NT.
4767 To build it from source, you must use the "gnu-win32" environment,
4768 which uses a DLL to emulate enough of Unix to run the GNU tools.
4769 Further information, binaries, and sources are available at
4770 ftp.cygnus.com, under pub/gnu-win32.
4772 * dont-repeat command
4774 If a user-defined command includes the command `dont-repeat', then the
4775 command will not be repeated if the user just types return. This is
4776 useful if the command is time-consuming to run, so that accidental
4777 extra keystrokes don't run the same command many times.
4779 * Send break instead of ^C
4781 The standard remote protocol now includes an option to send a break
4782 rather than a ^C to the target in order to interrupt it. By default,
4783 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4785 * Remote protocol timeout
4787 The standard remote protocol includes a new variable `remotetimeout'
4788 that allows you to set the number of seconds before GDB gives up trying
4789 to read from the target. The default value is 2.
4791 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4793 By default GDB will automatically keep track of objects as they are
4794 loaded and unloaded by the dynamic linker. By using the command `set
4795 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4796 when shared library events occur, thus allowing you to set breakpoints
4797 in shared libraries which are explicitly loaded by the inferior.
4799 Note this feature does not work on hpux8. On hpux9 you must link
4800 /usr/lib/end.o into your program. This feature should work
4801 automatically on hpux10.
4803 * Irix 5.x hardware watchpoint support
4805 Irix 5 configurations now support the use of hardware watchpoints.
4807 * Mips protocol "SYN garbage limit"
4809 When debugging a Mips target using the `target mips' protocol, you
4810 may set the number of characters that GDB will ignore by setting
4811 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4812 every character. The default value is 1050.
4814 * Recording and replaying remote debug sessions
4816 If you set `remotelogfile' to the name of a file, gdb will write to it
4817 a recording of a remote debug session. This recording may then be
4818 replayed back to gdb using "gdbreplay". See gdbserver/README for
4819 details. This is useful when you have a problem with GDB while doing
4820 remote debugging; you can make a recording of the session and send it
4821 to someone else, who can then recreate the problem.
4823 * Speedups for remote debugging
4825 GDB includes speedups for downloading and stepping MIPS systems using
4826 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4827 and more efficient S-record downloading.
4829 * Memory use reductions and statistics collection
4831 GDB now uses less memory and reports statistics about memory usage.
4832 Try the `maint print statistics' command, for example.
4834 *** Changes in GDB-4.15:
4836 * Psymtabs for XCOFF
4838 The symbol reader for AIX GDB now uses partial symbol tables. This
4839 can greatly improve startup time, especially for large executables.
4841 * Remote targets use caching
4843 Remote targets now use a data cache to speed up communication with the
4844 remote side. The data cache could lead to incorrect results because
4845 it doesn't know about volatile variables, thus making it impossible to
4846 debug targets which use memory mapped I/O devices. `set remotecache
4847 off' turns the the data cache off.
4849 * Remote targets may have threads
4851 The standard remote protocol now includes support for multiple threads
4852 in the target system, using new protocol commands 'H' and 'T'. See
4853 gdb/remote.c for details.
4857 If GDB is configured with `--enable-netrom', then it will include
4858 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4859 acts as though it is a bank of ROM on the target board, but you can
4860 write into it over the network. GDB's support consists only of
4861 support for fast loading into the emulated ROM; to debug, you must use
4862 another protocol, such as standard remote protocol. The usual
4863 sequence is something like
4865 target nrom <netrom-hostname>
4867 target remote <netrom-hostname>:1235
4871 GDB now includes support for the Apple Macintosh, as a host only. It
4872 may be run as either an MPW tool or as a standalone application, and
4873 it can debug through the serial port. All the usual GDB commands are
4874 available, but to the target command, you must supply "serial" as the
4875 device type instead of "/dev/ttyXX". See mpw-README in the main
4876 directory for more information on how to build. The MPW configuration
4877 scripts */mpw-config.in support only a few targets, and only the
4878 mips-idt-ecoff target has been tested.
4882 GDB configuration now uses autoconf. This is not user-visible,
4883 but does simplify configuration and building.
4887 GDB now supports hpux10.
4889 *** Changes in GDB-4.14:
4891 * New native configurations
4893 x86 FreeBSD i[345]86-*-freebsd
4894 x86 NetBSD i[345]86-*-netbsd
4895 NS32k NetBSD ns32k-*-netbsd
4896 Sparc NetBSD sparc-*-netbsd
4900 A29K VxWorks a29k-*-vxworks
4901 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4902 CPU32 EST-300 emulator m68*-*-est*
4903 PowerPC ELF powerpc-*-elf
4906 * Alpha OSF/1 support for procfs
4908 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4909 possible to attach to running processes. As the mounting of the /proc
4910 filesystem is optional on the Alpha, GDB automatically determines
4911 the availability of /proc during startup. This can lead to problems
4912 if /proc is unmounted after GDB has been started.
4914 * Arguments to user-defined commands
4916 User commands may accept up to 10 arguments separated by whitespace.
4917 Arguments are accessed within the user command via $arg0..$arg9. A
4920 print $arg0 + $arg1 + $arg2
4922 To execute the command use:
4925 Defines the command "adder" which prints the sum of its three arguments.
4926 Note the arguments are text substitutions, so they may reference variables,
4927 use complex expressions, or even perform inferior function calls.
4929 * New `if' and `while' commands
4931 This makes it possible to write more sophisticated user-defined
4932 commands. Both commands take a single argument, which is the
4933 expression to evaluate, and must be followed by the commands to
4934 execute, one per line, if the expression is nonzero, the list being
4935 terminated by the word `end'. The `if' command list may include an
4936 `else' word, which causes the following commands to be executed only
4937 if the expression is zero.
4939 * Fortran source language mode
4941 GDB now includes partial support for Fortran 77. It will recognize
4942 Fortran programs and can evaluate a subset of Fortran expressions, but
4943 variables and functions may not be handled correctly. GDB will work
4944 with G77, but does not yet know much about symbols emitted by other
4947 * Better HPUX support
4949 Most debugging facilities now work on dynamic executables for HPPAs
4950 running hpux9 or later. You can attach to running dynamically linked
4951 processes, but by default the dynamic libraries will be read-only, so
4952 for instance you won't be able to put breakpoints in them. To change
4953 that behavior do the following before running the program:
4959 This will cause the libraries to be mapped private and read-write.
4960 To revert to the normal behavior, do this:
4966 You cannot set breakpoints or examine data in the library until after
4967 the library is loaded if the function/data symbols do not have
4970 GDB can now also read debug symbols produced by the HP C compiler on
4971 HPPAs (sorry, no C++, Fortran or 68k support).
4973 * Target byte order now dynamically selectable
4975 You can choose which byte order to use with a target system, via the
4976 commands "set endian big" and "set endian little", and you can see the
4977 current setting by using "show endian". You can also give the command
4978 "set endian auto", in which case GDB will use the byte order
4979 associated with the executable. Currently, only embedded MIPS
4980 configurations support dynamic selection of target byte order.
4982 * New DOS host serial code
4984 This version uses DPMI interrupts to handle buffered I/O, so you
4985 no longer need to run asynctsr when debugging boards connected to
4988 *** Changes in GDB-4.13:
4990 * New "complete" command
4992 This lists all the possible completions for the rest of the line, if it
4993 were to be given as a command itself. This is intended for use by emacs.
4995 * Trailing space optional in prompt
4997 "set prompt" no longer adds a space for you after the prompt you set. This
4998 allows you to set a prompt which ends in a space or one that does not.
5000 * Breakpoint hit counts
5002 "info break" now displays a count of the number of times the breakpoint
5003 has been hit. This is especially useful in conjunction with "ignore"; you
5004 can ignore a large number of breakpoint hits, look at the breakpoint info
5005 to see how many times the breakpoint was hit, then run again, ignoring one
5006 less than that number, and this will get you quickly to the last hit of
5009 * Ability to stop printing at NULL character
5011 "set print null-stop" will cause GDB to stop printing the characters of
5012 an array when the first NULL is encountered. This is useful when large
5013 arrays actually contain only short strings.
5015 * Shared library breakpoints
5017 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5018 breakpoints in shared libraries before the executable is run.
5020 * Hardware watchpoints
5022 There is a new hardware breakpoint for the watch command for sparclite
5023 targets. See gdb/sparclite/hw_breakpoint.note.
5025 Hardware watchpoints are also now supported under GNU/Linux.
5029 Annotations have been added. These are for use with graphical interfaces,
5030 and are still experimental. Currently only gdba.el uses these.
5032 * Improved Irix 5 support
5034 GDB now works properly with Irix 5.2.
5036 * Improved HPPA support
5038 GDB now works properly with the latest GCC and GAS.
5040 * New native configurations
5042 Sequent PTX4 i[34]86-sequent-ptx4
5043 HPPA running OSF/1 hppa*-*-osf*
5044 Atari TT running SVR4 m68*-*-sysv4*
5045 RS/6000 LynxOS rs6000-*-lynxos*
5049 OS/9000 i[34]86-*-os9k
5050 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5053 * Hitachi SH7000 and E7000-PC ICE support
5055 There is now support for communicating with the Hitachi E7000-PC ICE.
5056 This is available automatically when GDB is configured for the SH.
5060 As usual, a variety of small fixes and improvements, both generic
5061 and configuration-specific. See the ChangeLog for more detail.
5063 *** Changes in GDB-4.12:
5065 * Irix 5 is now supported
5069 GDB-4.12 on the HPPA has a number of changes which make it unable
5070 to debug the output from the currently released versions of GCC and
5071 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5072 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5073 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5076 *** Changes in GDB-4.11:
5078 * User visible changes:
5082 The "set remotedebug" option is now consistent between the mips remote
5083 target, remote targets using the gdb-specific protocol, UDI (AMD's
5084 debug protocol for the 29k) and the 88k bug monitor. It is now an
5085 integer specifying a debug level (normally 0 or 1, but 2 means more
5086 debugging info for the mips target).
5088 * DEC Alpha native support
5090 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5091 debug info, but GDB works fairly well with the DEC compiler and should
5092 work with a future GCC release. See the README file for a few
5093 Alpha-specific notes.
5095 * Preliminary thread implementation
5097 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5099 * LynxOS native and target support for 386
5101 This release has been hosted on LynxOS 2.2, and also can be configured
5102 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5105 * Improvements in C++ mangling/demangling.
5107 This release has much better g++ debugging, specifically in name
5108 mangling/demangling, virtual function calls, print virtual table,
5109 call methods, ...etc.
5111 *** Changes in GDB-4.10:
5113 * User visible changes:
5115 Remote debugging using the GDB-specific (`target remote') protocol now
5116 supports the `load' command. This is only useful if you have some
5117 other way of getting the stub to the target system, and you can put it
5118 somewhere in memory where it won't get clobbered by the download.
5120 Filename completion now works.
5122 When run under emacs mode, the "info line" command now causes the
5123 arrow to point to the line specified. Also, "info line" prints
5124 addresses in symbolic form (as well as hex).
5126 All vxworks based targets now support a user settable option, called
5127 vxworks-timeout. This option represents the number of seconds gdb
5128 should wait for responses to rpc's. You might want to use this if
5129 your vxworks target is, perhaps, a slow software simulator or happens
5130 to be on the far side of a thin network line.
5134 This release contains support for using a DEC alpha as a GDB host for
5135 cross debugging. Native alpha debugging is not supported yet.
5138 *** Changes in GDB-4.9:
5142 This is the first GDB release which is accompanied by a matching testsuite.
5143 The testsuite requires installation of dejagnu, which should be available
5144 via ftp from most sites that carry GNU software.
5148 'Cfront' style demangling has had its name changed to 'ARM' style, to
5149 emphasize that it was written from the specifications in the C++ Annotated
5150 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5151 disclaimers, it still generated too much confusion with users attempting to
5152 use gdb with AT&T cfront.
5156 GDB now uses a standard remote interface to a simulator library.
5157 So far, the library contains simulators for the Zilog Z8001/2, the
5158 Hitachi H8/300, H8/500 and Super-H.
5160 * New targets supported
5162 H8/300 simulator h8300-hitachi-hms or h8300hms
5163 H8/500 simulator h8500-hitachi-hms or h8500hms
5164 SH simulator sh-hitachi-hms or sh
5165 Z8000 simulator z8k-zilog-none or z8ksim
5166 IDT MIPS board over serial line mips-idt-ecoff
5168 Cross-debugging to GO32 targets is supported. It requires a custom
5169 version of the i386-stub.c module which is integrated with the
5170 GO32 memory extender.
5172 * New remote protocols
5174 MIPS remote debugging protocol.
5176 * New source languages supported
5178 This version includes preliminary support for Chill, a Pascal like language
5179 used by telecommunications companies. Chill support is also being integrated
5180 into the GNU compiler, but we don't know when it will be publically available.
5183 *** Changes in GDB-4.8:
5185 * HP Precision Architecture supported
5187 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5188 version of this support was available as a set of patches from the
5189 University of Utah. GDB does not support debugging of programs
5190 compiled with the HP compiler, because HP will not document their file
5191 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5192 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5194 Many problems in the preliminary version have been fixed.
5196 * Faster and better demangling
5198 We have improved template demangling and fixed numerous bugs in the GNU style
5199 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5200 character types (wchar_t) are now supported. Demangling of each symbol is now
5201 only done once, and is cached when the symbol table for a file is read in.
5202 This results in a small increase in memory usage for C programs, a moderate
5203 increase in memory usage for C++ programs, and a fantastic speedup in
5206 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5207 from the specifications in the Annotated Reference Manual, which AT&T's
5208 compiler does not actually implement.
5210 * G++ multiple inheritance compiler problem
5212 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5213 inheritance lattices was reworked to properly discover ambiguities. We
5214 recently found an example which causes this new algorithm to fail in a
5215 very subtle way, producing bad debug information for those classes.
5216 The file 'gcc.patch' (in this directory) can be applied to gcc to
5217 circumvent the problem. A future GCC release will contain a complete
5220 The previous G++ debug info problem (mentioned below for the gdb-4.7
5221 release) is fixed in gcc version 2.3.2.
5223 * Improved configure script
5225 The `configure' script will now attempt to guess your system type if
5226 you don't supply a host system type. The old scheme of supplying a
5227 host system triplet is preferable over using this. All the magic is
5228 done in the new `config.guess' script. Examine it for details.
5230 We have also brought our configure script much more in line with the FSF's
5231 version. It now supports the --with-xxx options. In particular,
5232 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5233 The resulting GDB will not be able to read arbitrary object file formats --
5234 only the format ``expected'' to be used on the configured target system.
5235 We hope to make this the default in a future release.
5237 * Documentation improvements
5239 There's new internal documentation on how to modify GDB, and how to
5240 produce clean changes to the code. We implore people to read it
5241 before submitting changes.
5243 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5244 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5245 `info' files are also provided. To build `info' files from scratch,
5246 you will need the latest `makeinfo' release, which will be available in
5247 a future texinfo-X.Y release.
5249 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5250 We're not sure exactly which versions have this problem, but it has
5251 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5252 or better. If that isn't possible, there is a patch in
5253 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5254 around this problem.
5258 GDB now supports array constants that can be used in expressions typed in by
5259 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5260 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5263 The new directory `gdb/sparclite' contains a program that demonstrates
5264 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5266 * New native hosts supported
5268 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5269 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5271 * New targets supported
5273 AMD 29k family via UDI a29k-amd-udi or udi29k
5275 * New file formats supported
5277 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5278 HPUX core files, and SCO 3.2v2 core files.
5282 Attaching to processes now works again; thanks for the many bug reports.
5284 We have also stomped on a bunch of core dumps caused by
5285 printf_filtered("%s") problems.
5287 We eliminated a copyright problem on the rpc and ptrace header files
5288 for VxWorks, which was discovered at the last minute during the 4.7
5289 release. You should now be able to build a VxWorks GDB.
5291 You can now interrupt gdb while an attached process is running. This
5292 will cause the attached process to stop, and give control back to GDB.
5294 We fixed problems caused by using too many file descriptors
5295 for reading symbols from object files and libraries. This was
5296 especially a problem for programs that used many (~100) shared
5299 The `step' command now only enters a subroutine if there is line number
5300 information for the subroutine. Otherwise it acts like the `next'
5301 command. Previously, `step' would enter subroutines if there was
5302 any debugging information about the routine. This avoids problems
5303 when using `cc -g1' on MIPS machines.
5305 * Internal improvements
5307 GDB's internal interfaces have been improved to make it easier to support
5308 debugging of multiple languages in the future.
5310 GDB now uses a common structure for symbol information internally.
5311 Minimal symbols (derived from linkage symbols in object files), partial
5312 symbols (from a quick scan of debug information), and full symbols
5313 contain a common subset of information, making it easier to write
5314 shared code that handles any of them.
5316 * New command line options
5318 We now accept --silent as an alias for --quiet.
5322 The memory-mapped-malloc library is now licensed under the GNU Library
5323 General Public License.
5325 *** Changes in GDB-4.7:
5327 * Host/native/target split
5329 GDB has had some major internal surgery to untangle the support for
5330 hosts and remote targets. Now, when you configure GDB for a remote
5331 target, it will no longer load in all of the support for debugging
5332 local programs on the host. When fully completed and tested, this will
5333 ensure that arbitrary host/target combinations are possible.
5335 The primary conceptual shift is to separate the non-portable code in
5336 GDB into three categories. Host specific code is required any time GDB
5337 is compiled on that host, regardless of the target. Target specific
5338 code relates to the peculiarities of the target, but can be compiled on
5339 any host. Native specific code is everything else: it can only be
5340 built when the host and target are the same system. Child process
5341 handling and core file support are two common `native' examples.
5343 GDB's use of /proc for controlling Unix child processes is now cleaner.
5344 It has been split out into a single module under the `target_ops' vector,
5345 plus two native-dependent functions for each system that uses /proc.
5347 * New hosts supported
5349 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5350 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5351 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5353 * New targets supported
5355 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5356 68030 and CPU32 m68030-*-*, m68332-*-*
5358 * New native hosts supported
5360 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5361 (386bsd is not well tested yet)
5362 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5364 * New file formats supported
5366 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5367 supports reading of `a.out.adobe' object files, which are an a.out
5368 format extended with minimal information about multiple sections.
5372 `show copying' is the same as the old `info copying'.
5373 `show warranty' is the same as `info warrantee'.
5374 These were renamed for consistency. The old commands continue to work.
5376 `info handle' is a new alias for `info signals'.
5378 You can now define pre-command hooks, which attach arbitrary command
5379 scripts to any command. The commands in the hook will be executed
5380 prior to the user's command. You can also create a hook which will be
5381 executed whenever the program stops. See gdb.texinfo.
5385 We now deal with Cfront style name mangling, and can even extract type
5386 info from mangled symbols. GDB can automatically figure out which
5387 symbol mangling style your C++ compiler uses.
5389 Calling of methods and virtual functions has been improved as well.
5393 The crash that occured when debugging Sun Ansi-C compiled binaries is
5394 fixed. This was due to mishandling of the extra N_SO stabs output
5397 We also finally got Ultrix 4.2 running in house, and fixed core file
5398 support, with help from a dozen people on the net.
5400 John M. Farrell discovered that the reason that single-stepping was so
5401 slow on all of the Mips based platforms (primarily SGI and DEC) was
5402 that we were trying to demangle and lookup a symbol used for internal
5403 purposes on every instruction that was being stepped through. Changing
5404 the name of that symbol so that it couldn't be mistaken for a C++
5405 mangled symbol sped things up a great deal.
5407 Rich Pixley sped up symbol lookups in general by getting much smarter
5408 about when C++ symbol mangling is necessary. This should make symbol
5409 completion (TAB on the command line) much faster. It's not as fast as
5410 we'd like, but it's significantly faster than gdb-4.6.
5414 A new user controllable variable 'call_scratch_address' can
5415 specify the location of a scratch area to be used when GDB
5416 calls a function in the target. This is necessary because the
5417 usual method of putting the scratch area on the stack does not work
5418 in systems that have separate instruction and data spaces.
5420 We integrated changes to support the 29k UDI (Universal Debugger
5421 Interface), but discovered at the last minute that we didn't have all
5422 of the appropriate copyright paperwork. We are working with AMD to
5423 resolve this, and hope to have it available soon.
5427 We have sped up the remote serial line protocol, especially for targets
5428 with lots of registers. It now supports a new `expedited status' ('T')
5429 message which can be used in place of the existing 'S' status message.
5430 This allows the remote stub to send only the registers that GDB
5431 needs to make a quick decision about single-stepping or conditional
5432 breakpoints, eliminating the need to fetch the entire register set for
5433 each instruction being stepped through.
5435 The GDB remote serial protocol now implements a write-through cache for
5436 registers, only re-reading the registers if the target has run.
5438 There is also a new remote serial stub for SPARC processors. You can
5439 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5440 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5441 processor with a serial port.
5445 Configure.in files have become much easier to read and modify. A new
5446 `table driven' format makes it more obvious what configurations are
5447 supported, and what files each one uses.
5451 There is a new opcodes library which will eventually contain all of the
5452 disassembly routines and opcode tables. At present, it only contains
5453 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5454 disassembler (binutils/objdump) to share these routines.
5456 The libiberty library is now copylefted under the GNU Library General
5457 Public License. This allows more liberal use, and was done so libg++
5458 can use it. This makes no difference to GDB, since the Library License
5459 grants all the rights from the General Public License.
5463 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5464 reference to the stabs symbol info used by the debugger. It is (as far
5465 as we know) the only published document on this fascinating topic. We
5466 encourage you to read it, compare it to the stabs information on your
5467 system, and send improvements on the document in general (to
5468 bug-gdb@prep.ai.mit.edu).
5470 And, of course, many bugs have been fixed.
5473 *** Changes in GDB-4.6:
5475 * Better support for C++ function names
5477 GDB now accepts as input the "demangled form" of C++ overloaded function
5478 names and member function names, and can do command completion on such names
5479 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5480 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5481 Make use of command completion, it is your friend.
5483 GDB also now accepts a variety of C++ mangled symbol formats. They are
5484 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5485 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5486 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5487 for the list of formats.
5489 * G++ symbol mangling problem
5491 Recent versions of gcc have a bug in how they emit debugging information for
5492 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5493 directory) can be applied to gcc to fix the problem. Alternatively, if you
5494 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5495 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5496 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5499 * New 'maintenance' command
5501 All of the commands related to hacking GDB internals have been moved out of
5502 the main command set, and now live behind the 'maintenance' command. This
5503 can also be abbreviated as 'mt'. The following changes were made:
5505 dump-me -> maintenance dump-me
5506 info all-breakpoints -> maintenance info breakpoints
5507 printmsyms -> maintenance print msyms
5508 printobjfiles -> maintenance print objfiles
5509 printpsyms -> maintenance print psymbols
5510 printsyms -> maintenance print symbols
5512 The following commands are new:
5514 maintenance demangle Call internal GDB demangler routine to
5515 demangle a C++ link name and prints the result.
5516 maintenance print type Print a type chain for a given symbol
5518 * Change to .gdbinit file processing
5520 We now read the $HOME/.gdbinit file before processing the argv arguments
5521 (e.g. reading symbol files or core files). This allows global parameters to
5522 be set, which will apply during the symbol reading. The ./.gdbinit is still
5523 read after argv processing.
5525 * New hosts supported
5527 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5529 GNU/Linux support i386-unknown-linux or linux
5531 We are also including code to support the HP/PA running BSD and HPUX. This
5532 is almost guaranteed not to work, as we didn't have time to test or build it
5533 for this release. We are including it so that the more adventurous (or
5534 masochistic) of you can play with it. We also had major problems with the
5535 fact that the compiler that we got from HP doesn't support the -g option.
5538 * New targets supported
5540 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5542 * More smarts about finding #include files
5544 GDB now remembers the compilation directory for all include files, and for
5545 all files from which C is generated (like yacc and lex sources). This
5546 greatly improves GDB's ability to find yacc/lex sources, and include files,
5547 especially if you are debugging your program from a directory different from
5548 the one that contains your sources.
5550 We also fixed a bug which caused difficulty with listing and setting
5551 breakpoints in include files which contain C code. (In the past, you had to
5552 try twice in order to list an include file that you hadn't looked at before.)
5554 * Interesting infernals change
5556 GDB now deals with arbitrary numbers of sections, where the symbols for each
5557 section must be relocated relative to that section's landing place in the
5558 target's address space. This work was needed to support ELF with embedded
5559 stabs used by Solaris-2.0.
5561 * Bug fixes (of course!)
5563 There have been loads of fixes for the following things:
5564 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5565 i960, stabs, DOS(GO32), procfs, etc...
5567 See the ChangeLog for details.
5569 *** Changes in GDB-4.5:
5571 * New machines supported (host and target)
5573 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5575 SGI Irix-4.x mips-sgi-irix4 or iris4
5577 * New malloc package
5579 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5580 Mmalloc is capable of handling mutiple heaps of memory. It is also
5581 capable of saving a heap to a file, and then mapping it back in later.
5582 This can be used to greatly speedup the startup of GDB by using a
5583 pre-parsed symbol table which lives in a mmalloc managed heap. For
5584 more details, please read mmalloc/mmalloc.texi.
5588 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5589 'help info proc' for details.
5591 * MIPS ecoff symbol table format
5593 The code that reads MIPS symbol table format is now supported on all hosts.
5594 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5597 * File name changes for MS-DOS
5599 Many files in the config directories have been renamed to make it easier to
5600 support GDB on MS-DOSe systems (which have very restrictive file name
5601 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5602 environment) is close to working but has some remaining problems. Note
5603 that debugging of DOS programs is not supported, due to limitations
5604 in the ``operating system'', but it can be used to host cross-debugging.
5606 * Cross byte order fixes
5608 Many fixes have been made to support cross debugging of Sparc and MIPS
5609 targets from hosts whose byte order differs.
5611 * New -mapped and -readnow options
5613 If memory-mapped files are available on your system through the 'mmap'
5614 system call, you can use the -mapped option on the `file' or
5615 `symbol-file' commands to cause GDB to write the symbols from your
5616 program into a reusable file. If the program you are debugging is
5617 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5618 Future GDB debugging sessions will notice the presence of this file,
5619 and will quickly map in symbol information from it, rather than reading
5620 the symbol table from the executable program. Using the '-mapped'
5621 option in a GDB `file' or `symbol-file' command has the same effect as
5622 starting GDB with the '-mapped' command-line option.
5624 You can cause GDB to read the entire symbol table immediately by using
5625 the '-readnow' option with any of the commands that load symbol table
5626 information (or on the GDB command line). This makes the command
5627 slower, but makes future operations faster.
5629 The -mapped and -readnow options are typically combined in order to
5630 build a `fred.syms' file that contains complete symbol information.
5631 A simple GDB invocation to do nothing but build a `.syms' file for future
5634 gdb -batch -nx -mapped -readnow programname
5636 The `.syms' file is specific to the host machine on which GDB is run.
5637 It holds an exact image of GDB's internal symbol table. It cannot be
5638 shared across multiple host platforms.
5640 * longjmp() handling
5642 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5643 siglongjmp() without losing control. This feature has not yet been ported to
5644 all systems. It currently works on many 386 platforms, all MIPS-based
5645 platforms (SGI, DECstation, etc), and Sun3/4.
5649 Preliminary work has been put in to support the new Solaris OS from Sun. At
5650 this time, it can control and debug processes, but it is not capable of
5655 As always, many many bug fixes. The major areas were with g++, and mipsread.
5656 People using the MIPS-based platforms should experience fewer mysterious
5657 crashes and trashed symbol tables.
5659 *** Changes in GDB-4.4:
5661 * New machines supported (host and target)
5663 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5665 BSD Reno on Vax vax-dec-bsd
5666 Ultrix on Vax vax-dec-ultrix
5668 * New machines supported (target)
5670 AMD 29000 embedded, using EBMON a29k-none-none
5674 GDB continues to improve its handling of C++. `References' work better.
5675 The demangler has also been improved, and now deals with symbols mangled as
5676 per the Annotated C++ Reference Guide.
5678 GDB also now handles `stabs' symbol information embedded in MIPS
5679 `ecoff' symbol tables. Since the ecoff format was not easily
5680 extensible to handle new languages such as C++, this appeared to be a
5681 good way to put C++ debugging info into MIPS binaries. This option
5682 will be supported in the GNU C compiler, version 2, when it is
5685 * New features for SVR4
5687 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5688 shared libraries. Debugging dynamically linked programs should present
5689 only minor differences from debugging statically linked programs.
5691 The `info proc' command will print out information about any process
5692 on an SVR4 system (including the one you are debugging). At the moment,
5693 it prints the address mappings of the process.
5695 If you bring up GDB on another SVR4 system, please send mail to
5696 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5698 * Better dynamic linking support in SunOS
5700 Reading symbols from shared libraries which contain debugging symbols
5701 now works properly. However, there remain issues such as automatic
5702 skipping of `transfer vector' code during function calls, which
5703 make it harder to debug code in a shared library, than to debug the
5704 same code linked statically.
5708 GDB is now using the latest `getopt' routines from the FSF. This
5709 version accepts the -- prefix for options with long names. GDB will
5710 continue to accept the old forms (-option and +option) as well.
5711 Various single letter abbreviations for options have been explicity
5712 added to the option table so that they won't get overshadowed in the
5713 future by other options that begin with the same letter.
5717 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5718 Many assorted bugs have been handled. Many more remain to be handled.
5719 See the various ChangeLog files (primarily in gdb and bfd) for details.
5722 *** Changes in GDB-4.3:
5724 * New machines supported (host and target)
5726 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5727 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5728 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5730 * Almost SCO Unix support
5732 We had hoped to support:
5733 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5734 (except for core file support), but we discovered very late in the release
5735 that it has problems with process groups that render gdb unusable. Sorry
5736 about that. I encourage people to fix it and post the fixes.
5738 * Preliminary ELF and DWARF support
5740 GDB can read ELF object files on System V Release 4, and can handle
5741 debugging records for C, in DWARF format, in ELF files. This support
5742 is preliminary. If you bring up GDB on another SVR4 system, please
5743 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5748 GDB now uses the latest `readline' library. One user-visible change
5749 is that two tabs will list possible command completions, which previously
5750 required typing M-? (meta-question mark, or ESC ?).
5754 The `stepi' bug that many of you noticed has been squashed.
5755 Many bugs in C++ have been handled. Many more remain to be handled.
5756 See the various ChangeLog files (primarily in gdb and bfd) for details.
5758 * State of the MIPS world (in case you wondered):
5760 GDB can understand the symbol tables emitted by the compilers
5761 supplied by most vendors of MIPS-based machines, including DEC. These
5762 symbol tables are in a format that essentially nobody else uses.
5764 Some versions of gcc come with an assembler post-processor called
5765 mips-tfile. This program is required if you want to do source-level
5766 debugging of gcc-compiled programs. I believe FSF does not ship
5767 mips-tfile with gcc version 1, but it will eventually come with gcc
5770 Debugging of g++ output remains a problem. g++ version 1.xx does not
5771 really support it at all. (If you're lucky, you should be able to get
5772 line numbers and stack traces to work, but no parameters or local
5773 variables.) With some work it should be possible to improve the
5776 When gcc version 2 is released, you will have somewhat better luck.
5777 However, even then you will get confusing results for inheritance and
5780 We will eventually provide full debugging of g++ output on
5781 DECstations. This will probably involve some kind of stabs-in-ecoff
5782 encapulation, but the details have not been worked out yet.
5785 *** Changes in GDB-4.2:
5787 * Improved configuration
5789 Only one copy of `configure' exists now, and it is not self-modifying.
5790 Porting BFD is simpler.
5794 The `step' and `next' commands now only stop at the first instruction
5795 of a source line. This prevents the multiple stops that used to occur
5796 in switch statements, for-loops, etc. `Step' continues to stop if a
5797 function that has debugging information is called within the line.
5801 Lots of small bugs fixed. More remain.
5803 * New host supported (not target)
5805 Intel 386 PC clone running Mach i386-none-mach
5808 *** Changes in GDB-4.1:
5810 * Multiple source language support
5812 GDB now has internal scaffolding to handle several source languages.
5813 It determines the type of each source file from its filename extension,
5814 and will switch expression parsing and number formatting to match the
5815 language of the function in the currently selected stack frame.
5816 You can also specifically set the language to be used, with
5817 `set language c' or `set language modula-2'.
5821 GDB now has preliminary support for the GNU Modula-2 compiler,
5822 currently under development at the State University of New York at
5823 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5824 continue through the fall of 1991 and into 1992.
5826 Other Modula-2 compilers are currently not supported, and attempting to
5827 debug programs compiled with them will likely result in an error as the
5828 symbol table is read. Feel free to work on it, though!
5830 There are hooks in GDB for strict type checking and range checking,
5831 in the `Modula-2 philosophy', but they do not currently work.
5835 GDB can now write to executable and core files (e.g. patch
5836 a variable's value). You must turn this switch on, specify
5837 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5838 by assigning a new value to a variable. Modifications take
5841 * Automatic SunOS shared library reading
5843 When you run your program, GDB automatically determines where its
5844 shared libraries (if any) have been loaded, and reads their symbols.
5845 The `share' command is no longer needed. This also works when
5846 examining core files.
5850 You can specify the number of lines that the `list' command shows.
5853 * New machines supported (host and target)
5855 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5856 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5857 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5859 * New hosts supported (not targets)
5861 IBM RT/PC: romp-ibm-aix or rtpc
5863 * New targets supported (not hosts)
5865 AMD 29000 embedded with COFF a29k-none-coff
5866 AMD 29000 embedded with a.out a29k-none-aout
5867 Ultracomputer remote kernel debug a29k-nyu-kern
5869 * New remote interfaces
5875 *** Changes in GDB-4.0:
5879 Wide output is wrapped at good places to make the output more readable.
5881 Gdb now supports cross-debugging from a host machine of one type to a
5882 target machine of another type. Communication with the target system
5883 is over serial lines. The ``target'' command handles connecting to the
5884 remote system; the ``load'' command will download a program into the
5885 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5886 also supports debugging of realtime processes running under VxWorks,
5887 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5888 stub on the target system.
5890 New CPUs supported include the AMD 29000 and Intel 960.
5892 GDB now reads object files and symbol tables via a ``binary file''
5893 library, which allows a single copy of GDB to debug programs of multiple
5894 object file types such as a.out and coff.
5896 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5897 refcard.dvi and refcard.ps are available to format it).
5900 * Control-Variable user interface simplified
5902 All variables that control the operation of the debugger can be set
5903 by the ``set'' command, and displayed by the ``show'' command.
5905 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5906 ``Show prompt'' produces the response:
5907 Gdb's prompt is new-gdb=>.
5909 What follows are the NEW set commands. The command ``help set'' will
5910 print a complete list of old and new set commands. ``help set FOO''
5911 will give a longer description of the variable FOO. ``show'' will show
5912 all of the variable descriptions and their current settings.
5914 confirm on/off: Enables warning questions for operations that are
5915 hard to recover from, e.g. rerunning the program while
5916 it is already running. Default is ON.
5918 editing on/off: Enables EMACS style command line editing
5919 of input. Previous lines can be recalled with
5920 control-P, the current line can be edited with control-B,
5921 you can search for commands with control-R, etc.
5924 history filename NAME: NAME is where the gdb command history
5925 will be stored. The default is .gdb_history,
5926 or the value of the environment variable
5929 history size N: The size, in commands, of the command history. The
5930 default is 256, or the value of the environment variable
5933 history save on/off: If this value is set to ON, the history file will
5934 be saved after exiting gdb. If set to OFF, the
5935 file will not be saved. The default is OFF.
5937 history expansion on/off: If this value is set to ON, then csh-like
5938 history expansion will be performed on
5939 command line input. The default is OFF.
5941 radix N: Sets the default radix for input and output. It can be set
5942 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5943 in the current radix, so "set radix 10" is always a no-op.
5945 height N: This integer value is the number of lines on a page. Default
5946 is 24, the current `stty rows'' setting, or the ``li#''
5947 setting from the termcap entry matching the environment
5950 width N: This integer value is the number of characters on a line.
5951 Default is 80, the current `stty cols'' setting, or the ``co#''
5952 setting from the termcap entry matching the environment
5955 Note: ``set screensize'' is obsolete. Use ``set height'' and
5956 ``set width'' instead.
5958 print address on/off: Print memory addresses in various command displays,
5959 such as stack traces and structure values. Gdb looks
5960 more ``symbolic'' if you turn this off; it looks more
5961 ``machine level'' with it on. Default is ON.
5963 print array on/off: Prettyprint arrays. New convenient format! Default
5966 print demangle on/off: Print C++ symbols in "source" form if on,
5969 print asm-demangle on/off: Same, for assembler level printouts
5972 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5975 * Support for Epoch Environment.
5977 The epoch environment is a version of Emacs v18 with windowing. One
5978 new command, ``inspect'', is identical to ``print'', except that if you
5979 are running in the epoch environment, the value is printed in its own
5983 * Support for Shared Libraries
5985 GDB can now debug programs and core files that use SunOS shared libraries.
5986 Symbols from a shared library cannot be referenced
5987 before the shared library has been linked with the program (this
5988 happens after you type ``run'' and before the function main() is entered).
5989 At any time after this linking (including when examining core files
5990 from dynamically linked programs), gdb reads the symbols from each
5991 shared library when you type the ``sharedlibrary'' command.
5992 It can be abbreviated ``share''.
5994 sharedlibrary REGEXP: Load shared object library symbols for files
5995 matching a unix regular expression. No argument
5996 indicates to load symbols for all shared libraries.
5998 info sharedlibrary: Status of loaded shared libraries.
6003 A watchpoint stops execution of a program whenever the value of an
6004 expression changes. Checking for this slows down execution
6005 tremendously whenever you are in the scope of the expression, but is
6006 quite useful for catching tough ``bit-spreader'' or pointer misuse
6007 problems. Some machines such as the 386 have hardware for doing this
6008 more quickly, and future versions of gdb will use this hardware.
6010 watch EXP: Set a watchpoint (breakpoint) for an expression.
6012 info watchpoints: Information about your watchpoints.
6014 delete N: Deletes watchpoint number N (same as breakpoints).
6015 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6016 enable N: Re-enables watchpoint number N (same as breakpoints).
6019 * C++ multiple inheritance
6021 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6024 * C++ exception handling
6026 Gdb now supports limited C++ exception handling. Besides the existing
6027 ability to breakpoint on an exception handler, gdb can breakpoint on
6028 the raising of an exception (before the stack is peeled back to the
6031 catch FOO: If there is a FOO exception handler in the dynamic scope,
6032 set a breakpoint to catch exceptions which may be raised there.
6033 Multiple exceptions (``catch foo bar baz'') may be caught.
6035 info catch: Lists all exceptions which may be caught in the
6036 current stack frame.
6039 * Minor command changes
6041 The command ``call func (arg, arg, ...)'' now acts like the print
6042 command, except it does not print or save a value if the function's result
6043 is void. This is similar to dbx usage.
6045 The ``up'' and ``down'' commands now always print the frame they end up
6046 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6047 frames without printing.
6049 * New directory command
6051 'dir' now adds directories to the FRONT of the source search path.
6052 The path starts off empty. Source files that contain debug information
6053 about the directory in which they were compiled can be found even
6054 with an empty path; Sun CC and GCC include this information. If GDB can't
6055 find your source file in the current directory, type "dir .".
6057 * Configuring GDB for compilation
6059 For normal use, type ``./configure host''. See README or gdb.texinfo
6062 GDB now handles cross debugging. If you are remotely debugging between
6063 two different machines, type ``./configure host -target=targ''.
6064 Host is the machine where GDB will run; targ is the machine
6065 where the program that you are debugging will run.