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 * Directory names supplied to the "set sysroot" commands may be
27 prefixed with "target:" to tell GDB to access shared libraries from
28 the target system, be it local or remote. This replaces the prefix
29 "remote:". The default sysroot has been changed from "" to
30 "target:". "remote:" is automatically converted to "target:" for
31 backward compatibility.
33 * The system root specified by "set sysroot" will be prepended to the
34 filename of the main executable (if reported to GDB as absolute by
35 the operating system) when starting processes remotely, and when
36 attaching to already-running local or remote processes.
38 * GDB now supports automatic location and retrieval of executable
39 files from remote targets. Remote debugging can now be initiated
40 using only a "target remote" or "target extended-remote" command
41 (no "set sysroot" or "file" commands are required). See "New remote
44 * The "dump" command now supports verilog hex format.
46 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
50 ** gdb.Objfile objects have a new attribute "username",
51 which is the name of the objfile as specified by the user,
52 without, for example, resolving symlinks.
53 ** You can now write frame unwinders in Python.
54 ** gdb.Type objects have a new method "optimized_out",
55 returning optimized out gdb.Value instance of this type.
56 ** Xmethods can now specify a result type.
60 maint print symbol-cache
61 Print the contents of the symbol cache.
63 maint print symbol-cache-statistics
64 Print statistics of symbol cache usage.
66 maint flush-symbol-cache
67 Flush the contents of the symbol cache.
71 Start branch trace recording using Branch Trace Store (BTS) format.
77 Set the maximum number of candidates to be considered during
78 completion. The default value is 200. This limit allows GDB
79 to avoid generating large completion lists, the computation of
80 which can cause the debugger to become temporarily unresponsive.
82 maint set symbol-cache-size
83 maint show symbol-cache-size
84 Control the size of the symbol cache.
86 set|show record btrace bts buffer-size
87 Set and show the size of the ring buffer used for branch tracing in
89 The obtained size may differ from the requested size. Use "info
90 record" to see the obtained buffer size.
92 * The command 'thread apply all' can now support new option '-ascending'
93 to call its specified command for all threads in ascending order.
95 * Python/Guile scripting
97 ** GDB now supports auto-loading of Python/Guile scripts contained in the
98 special section named `.debug_gdb_scripts'.
102 qXfer:btrace-conf:read
103 Return the branch trace configuration for the current thread.
105 Qbtrace-conf:bts:size
106 Set the requested ring buffer size for branch tracing in BTS format.
109 Indicates a memory breakpoint instruction was executed, irrespective
110 of whether it was GDB that planted the breakpoint or the breakpoint
111 is hardcoded in the program. This is required for correct non-stop
115 Indicates the target stopped for a hardware breakpoint. This is
116 required for correct non-stop mode operation.
119 Return information about files on the remote system.
122 Return the full absolute name of the file that was executed to
123 create a process running on the remote system.
125 * The info record command now shows the recording format and the
126 branch tracing configuration for the current thread when using
127 the btrace record target.
128 For the BTS format, it shows the ring buffer size.
130 * GDB now has support for DTrace USDT (Userland Static Defined
131 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
133 * GDB now supports access to vector registers on S/390 GNU/Linux
136 * Removed command line options
138 -xdb HP-UX XDB compatibility mode.
140 * Removed targets and native configurations
142 HP/PA running HP-UX hppa*-*-hpux*
143 Itanium running HP-UX ia64-*-hpux*
145 *** Changes in GDB 7.9
147 * GDB now supports hardware watchpoints on x86 GNU Hurd.
151 ** You can now access frame registers from Python scripts.
152 ** New attribute 'producer' for gdb.Symtab objects.
153 ** gdb.Objfile objects have a new attribute "progspace",
154 which is the gdb.Progspace object of the containing program space.
155 ** gdb.Objfile objects have a new attribute "owner".
156 ** gdb.Objfile objects have a new attribute "build_id",
157 which is the build ID generated when the file was built.
158 ** gdb.Objfile objects have a new method "add_separate_debug_file".
159 ** A new event "gdb.clear_objfiles" has been added, triggered when
160 selecting a new file to debug.
161 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
162 ** New function gdb.lookup_objfile.
164 New events which are triggered when GDB modifies the state of the
167 ** gdb.events.inferior_call_pre: Function call is about to be made.
168 ** gdb.events.inferior_call_post: Function call has just been made.
169 ** gdb.events.memory_changed: A memory location has been altered.
170 ** gdb.events.register_changed: A register has been altered.
172 * New Python-based convenience functions:
174 ** $_caller_is(name [, number_of_frames])
175 ** $_caller_matches(regexp [, number_of_frames])
176 ** $_any_caller_is(name [, number_of_frames])
177 ** $_any_caller_matches(regexp [, number_of_frames])
179 * GDB now supports the compilation and injection of source code into
180 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
181 to compile the source code to object code, and if successful, inject
182 and execute that code within the current context of the inferior.
183 Currently the C language is supported. The commands used to
184 interface with this new feature are:
186 compile code [-raw|-r] [--] [source code]
187 compile file [-raw|-r] filename
191 demangle [-l language] [--] name
192 Demangle "name" in the specified language, or the current language
193 if elided. This command is renamed from the "maint demangle" command.
194 The latter is kept as a no-op to avoid "maint demangle" being interpreted
195 as "maint demangler-warning".
197 queue-signal signal-name-or-number
198 Queue a signal to be delivered to the thread when it is resumed.
200 add-auto-load-scripts-directory directory
201 Add entries to the list of directories from which to load auto-loaded
204 maint print user-registers
205 List all currently available "user" registers.
207 compile code [-r|-raw] [--] [source code]
208 Compile, inject, and execute in the inferior the executable object
209 code produced by compiling the provided source code.
211 compile file [-r|-raw] filename
212 Compile and inject into the inferior the executable object code
213 produced by compiling the source code stored in the filename
216 * On resume, GDB now always passes the signal the program had stopped
217 for to the thread the signal was sent to, even if the user changed
218 threads before resuming. Previously GDB would often (but not
219 always) deliver the signal to the thread that happens to be current
222 * Conversely, the "signal" command now consistently delivers the
223 requested signal to the current thread. GDB now asks for
224 confirmation if the program had stopped for a signal and the user
225 switched threads meanwhile.
227 * "breakpoint always-inserted" modes "off" and "auto" merged.
229 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
230 won't remove breakpoints from the target until all threads stop,
231 even in non-stop mode. The "auto" mode has been removed, and "off"
232 is now the default mode.
236 set debug symbol-lookup
237 show debug symbol-lookup
238 Control display of debugging info regarding symbol lookup.
242 ** The -list-thread-groups command outputs an exit-code field for
243 inferiors that have exited.
247 MIPS SDE mips*-sde*-elf*
251 Support for these obsolete configurations has been removed.
253 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
254 SGI Irix-5.x mips-*-irix5*
255 SGI Irix-6.x mips-*-irix6*
256 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
257 VAX running Ultrix vax-*-ultrix*
259 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
260 and "assf"), have been removed. Use the "sharedlibrary" command, or
261 its alias "share", instead.
263 *** Changes in GDB 7.8
265 * New command line options
268 This is an alias for the --data-directory option.
270 * GDB supports printing and modifying of variable length automatic arrays
271 as specified in ISO C99.
273 * The ARM simulator now supports instruction level tracing
274 with or without disassembly.
278 GDB now has support for scripting using Guile. Whether this is
279 available is determined at configure time.
280 Guile version 2.0 or greater is required.
281 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
283 * New commands (for set/show, see "New options" below)
287 Invoke CODE by passing it to the Guile interpreter.
291 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
293 info auto-load guile-scripts [regexp]
294 Print the list of automatically loaded Guile scripts.
296 * The source command is now capable of sourcing Guile scripts.
297 This feature is dependent on the debugger being built with Guile support.
301 set print symbol-loading (off|brief|full)
302 show print symbol-loading
303 Control whether to print informational messages when loading symbol
304 information for a file. The default is "full", but when debugging
305 programs with large numbers of shared libraries the amount of output
308 set guile print-stack (none|message|full)
309 show guile print-stack
310 Show a stack trace when an error is encountered in a Guile script.
312 set auto-load guile-scripts (on|off)
313 show auto-load guile-scripts
314 Control auto-loading of Guile script files.
316 maint ada set ignore-descriptive-types (on|off)
317 maint ada show ignore-descriptive-types
318 Control whether the debugger should ignore descriptive types in Ada
319 programs. The default is not to ignore the descriptive types. See
320 the user manual for more details on descriptive types and the intended
321 usage of this option.
323 set auto-connect-native-target
325 Control whether GDB is allowed to automatically connect to the
326 native target for the run, attach, etc. commands when not connected
327 to any target yet. See also "target native" below.
329 set record btrace replay-memory-access (read-only|read-write)
330 show record btrace replay-memory-access
331 Control what memory accesses are allowed during replay.
333 maint set target-async (on|off)
334 maint show target-async
335 This controls whether GDB targets operate in synchronous or
336 asynchronous mode. Normally the default is asynchronous, if it is
337 available; but this can be changed to more easily debug problems
338 occurring only in synchronous mode.
340 set mi-async (on|off)
342 Control whether MI asynchronous mode is preferred. This supersedes
343 "set target-async" of previous GDB versions.
345 * "set target-async" is deprecated as a CLI option and is now an alias
346 for "set mi-async" (only puts MI into async mode).
348 * Background execution commands (e.g., "c&", "s&", etc.) are now
349 possible ``out of the box'' if the target supports them. Previously
350 the user would need to explicitly enable the possibility with the
351 "set target-async on" command.
353 * New features in the GDB remote stub, GDBserver
355 ** New option --debug-format=option1[,option2,...] allows one to add
356 additional text to each output. At present only timestamps
357 are supported: --debug-format=timestamps.
358 Timestamps can also be turned on with the
359 "monitor set debug-format timestamps" command from GDB.
361 * The 'record instruction-history' command now starts counting instructions
362 at one. This also affects the instruction ranges reported by the
363 'record function-call-history' command when given the /i modifier.
365 * The command 'record function-call-history' supports a new modifier '/c' to
366 indent the function names based on their call stack depth.
367 The fields for the '/i' and '/l' modifier have been reordered.
368 The source line range is now prefixed with 'at'.
369 The instruction range is now prefixed with 'inst'.
370 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
371 "record instruction-history" and "list" commands.
373 * The ranges given as arguments to the 'record function-call-history' and
374 'record instruction-history' commands are now inclusive.
376 * The btrace record target now supports the 'record goto' command.
377 For locations inside the execution trace, the back trace is computed
378 based on the information stored in the execution trace.
380 * The btrace record target supports limited reverse execution and replay.
381 The target does not record data and therefore does not allow reading
384 * The "catch syscall" command now works on s390*-linux* targets.
386 * The "compare-sections" command is no longer specific to target
387 remote. It now works with all targets.
389 * All native targets are now consistently called "native".
390 Consequently, the "target child", "target GNU", "target djgpp",
391 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
392 commands have been replaced with "target native". The QNX/NTO port
393 leaves the "procfs" target in place and adds a "native" target for
394 consistency with other ports. The impact on users should be minimal
395 as these commands previously either throwed an error, or were
396 no-ops. The target's name is visible in the output of the following
397 commands: "help target", "info target", "info files", "maint print
400 * The "target native" command now connects to the native target. This
401 can be used to launch native programs even when "set
402 auto-connect-native-target" is set to off.
404 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
406 * Support for Intel(R) AVX-512 registers on GNU/Linux.
407 Support displaying and modifying Intel(R) AVX-512 registers
408 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
412 qXfer:btrace:read's annex
413 The qXfer:btrace:read packet supports a new annex 'delta' to read
414 branch trace incrementally.
418 ** Valid Python operations on gdb.Value objects representing
419 structs/classes invoke the corresponding overloaded operators if
421 ** New `Xmethods' feature in the Python API. Xmethods are
422 additional methods or replacements for existing methods of a C++
423 class. This feature is useful for those cases where a method
424 defined in C++ source code could be inlined or optimized out by
425 the compiler, making it unavailable to GDB.
428 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
430 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
431 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
432 its alias "share", instead.
434 * The commands "set remotebaud" and "show remotebaud" are no longer
435 supported. Use "set serial baud" and "show serial baud" (respectively)
440 ** A new option "-gdb-set mi-async" replaces "-gdb-set
441 target-async". The latter is left as a deprecated alias of the
442 former for backward compatibility. If the target supports it,
443 CLI background execution commands are now always possible by
444 default, independently of whether the frontend stated a
445 preference for asynchronous execution with "-gdb-set mi-async".
446 Previously "-gdb-set target-async off" affected both MI execution
447 commands and CLI execution commands.
449 *** Changes in GDB 7.7
451 * Improved support for process record-replay and reverse debugging on
452 arm*-linux* targets. Support for thumb32 and syscall instruction
453 recording has been added.
455 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
457 * GDB now supports Fission DWP file format version 2.
458 http://gcc.gnu.org/wiki/DebugFission
460 * New convenience function "$_isvoid", to check whether an expression
461 is void. A void expression is an expression where the type of the
462 result is "void". For example, some convenience variables may be
463 "void" when evaluated (e.g., "$_exitcode" before the execution of
464 the program being debugged; or an undefined convenience variable).
465 Another example, when calling a function whose return type is
468 * The "maintenance print objfiles" command now takes an optional regexp.
470 * The "catch syscall" command now works on arm*-linux* targets.
472 * GDB now consistently shows "<not saved>" when printing values of
473 registers the debug info indicates have not been saved in the frame
474 and there's nowhere to retrieve them from
475 (callee-saved/call-clobbered registers):
480 (gdb) info registers rax
483 Before, the former would print "<optimized out>", and the latter
484 "*value not available*".
486 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
491 ** Frame filters and frame decorators have been added.
492 ** Temporary breakpoints are now supported.
493 ** Line tables representation has been added.
494 ** New attribute 'parent_type' for gdb.Field objects.
495 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
496 ** New attribute 'name' for gdb.Type objects.
500 Nios II ELF nios2*-*-elf
501 Nios II GNU/Linux nios2*-*-linux
502 Texas Instruments MSP430 msp430*-*-elf
504 * Removed native configurations
506 Support for these a.out NetBSD and OpenBSD obsolete configurations has
507 been removed. ELF variants of these configurations are kept supported.
509 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
510 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
511 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
512 i[34567]86-*-openbsd3.[0-3]
513 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
514 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
515 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
519 Like "catch throw", but catches a re-thrown exception.
521 Renamed from old "maint check-symtabs".
523 Perform consistency checks on symtabs.
525 Expand symtabs matching an optional regexp.
528 Display the details of GDB configure-time options.
530 maint set|show per-command
531 maint set|show per-command space
532 maint set|show per-command time
533 maint set|show per-command symtab
534 Enable display of per-command gdb resource usage.
536 remove-symbol-file FILENAME
537 remove-symbol-file -a ADDRESS
538 Remove a symbol file added via add-symbol-file. The file to remove
539 can be identified by its filename or by an address that lies within
540 the boundaries of this symbol file in memory.
543 info exceptions REGEXP
544 Display the list of Ada exceptions defined in the program being
545 debugged. If provided, only the exceptions whose names match REGEXP
550 set debug symfile off|on
552 Control display of debugging info regarding reading symbol files and
553 symbol tables within those files
555 set print raw frame-arguments
556 show print raw frame-arguments
557 Set/show whether to print frame arguments in raw mode,
558 disregarding any defined pretty-printers.
560 set remote trace-status-packet
561 show remote trace-status-packet
562 Set/show the use of remote protocol qTStatus packet.
566 Control display of debugging messages related to Nios II targets.
570 Control whether target-assisted range stepping is enabled.
572 set startup-with-shell
573 show startup-with-shell
574 Specifies whether Unix child processes are started via a shell or
579 Use the target memory cache for accesses to the code segment. This
580 improves performance of remote debugging (particularly disassembly).
582 * You can now use a literal value 'unlimited' for options that
583 interpret 0 or -1 as meaning "unlimited". E.g., "set
584 trace-buffer-size unlimited" is now an alias for "set
585 trace-buffer-size -1" and "set height unlimited" is now an alias for
588 * The "set debug symtab-create" debugging option of GDB has been changed to
589 accept a verbosity level. 0 means "off", 1 provides basic debugging
590 output, and values of 2 or greater provides more verbose output.
592 * New command-line options
594 Display the details of GDB configure-time options.
596 * The command 'tsave' can now support new option '-ctf' to save trace
597 buffer in Common Trace Format.
599 * Newly installed $prefix/bin/gcore acts as a shell interface for the
602 * GDB now implements the the C++ 'typeid' operator.
604 * The new convenience variable $_exception holds the exception being
605 thrown or caught at an exception-related catchpoint.
607 * The exception-related catchpoints, like "catch throw", now accept a
608 regular expression which can be used to filter exceptions by type.
610 * The new convenience variable $_exitsignal is automatically set to
611 the terminating signal number when the program being debugged dies
612 due to an uncaught signal.
616 ** All MI commands now accept an optional "--language" option.
617 Support for this feature can be verified by using the "-list-features"
618 command, which should contain "language-option".
620 ** The new command -info-gdb-mi-command allows the user to determine
621 whether a GDB/MI command is supported or not.
623 ** The "^error" result record returned when trying to execute an undefined
624 GDB/MI command now provides a variable named "code" whose content is the
625 "undefined-command" error code. Support for this feature can be verified
626 by using the "-list-features" command, which should contain
627 "undefined-command-error-code".
629 ** The -trace-save MI command can optionally save trace buffer in Common
632 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
634 ** The command -data-list-register-values now accepts an optional
635 "--skip-unavailable" option. When used, only the available registers
638 ** The new command -trace-frame-collected dumps collected variables,
639 computed expressions, tvars, memory and registers in a traceframe.
641 ** The commands -stack-list-locals, -stack-list-arguments and
642 -stack-list-variables now accept an option "--skip-unavailable".
643 When used, only the available locals or arguments are displayed.
645 ** The -exec-run command now accepts an optional "--start" option.
646 When used, the command follows the same semantics as the "start"
647 command, stopping the program's execution at the start of its
648 main subprogram. Support for this feature can be verified using
649 the "-list-features" command, which should contain
650 "exec-run-start-option".
652 ** The new commands -catch-assert and -catch-exceptions insert
653 catchpoints stopping the program when Ada exceptions are raised.
655 ** The new command -info-ada-exceptions provides the equivalent of
656 the new "info exceptions" command.
658 * New system-wide configuration scripts
659 A GDB installation now provides scripts suitable for use as system-wide
660 configuration scripts for the following systems:
664 * GDB now supports target-assigned range stepping with remote targets.
665 This improves the performance of stepping source lines by reducing
666 the number of control packets from/to GDB. See "New remote packets"
669 * GDB now understands the element 'tvar' in the XML traceframe info.
670 It has the id of the collected trace state variables.
672 * On S/390 targets that provide the transactional-execution feature,
673 the program interruption transaction diagnostic block (TDB) is now
674 represented as a number of additional "registers" in GDB.
680 The vCont packet supports a new 'r' action, that tells the remote
681 stub to step through an address range itself, without GDB
682 involvemement at each single-step.
684 qXfer:libraries-svr4:read's annex
685 The previously unused annex of the qXfer:libraries-svr4:read packet
686 is now used to support passing an argument list. The remote stub
687 reports support for this argument list to GDB's qSupported query.
688 The defined arguments are "start" and "prev", used to reduce work
689 necessary for library list updating, resulting in significant
692 * New features in the GDB remote stub, GDBserver
694 ** GDBserver now supports target-assisted range stepping. Currently
695 enabled on x86/x86_64 GNU/Linux targets.
697 ** GDBserver now adds element 'tvar' in the XML in the reply to
698 'qXfer:traceframe-info:read'. It has the id of the collected
699 trace state variables.
701 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
704 * New 'z' formatter for printing and examining memory, this displays the
705 value as hexadecimal zero padded on the left to the size of the type.
707 * GDB can now use Windows x64 unwinding data.
709 * The "set remotebaud" command has been replaced by "set serial baud".
710 Similarly, "show remotebaud" has been replaced by "show serial baud".
711 The "set remotebaud" and "show remotebaud" commands are still available
712 to provide backward compatibility with older versions of GDB.
714 *** Changes in GDB 7.6
716 * Target record has been renamed to record-full.
717 Record/replay is now enabled with the "record full" command.
718 This also affects settings that are associated with full record/replay
719 that have been moved from "set/show record" to "set/show record full":
721 set|show record full insn-number-max
722 set|show record full stop-at-limit
723 set|show record full memory-query
725 * A new record target "record-btrace" has been added. The new target
726 uses hardware support to record the control-flow of a process. It
727 does not support replaying the execution, but it implements the
728 below new commands for investigating the recorded execution log.
729 This new recording method can be enabled using:
733 The "record-btrace" target is only available on Intel Atom processors
734 and requires a Linux kernel 2.6.32 or later.
736 * Two new commands have been added for record/replay to give information
737 about the recorded execution without having to replay the execution.
738 The commands are only supported by "record btrace".
740 record instruction-history prints the execution history at
741 instruction granularity
743 record function-call-history prints the execution history at
746 * New native configurations
748 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
749 FreeBSD/powerpc powerpc*-*-freebsd
750 x86_64/Cygwin x86_64-*-cygwin*
751 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
755 ARM AArch64 aarch64*-*-elf
756 ARM AArch64 GNU/Linux aarch64*-*-linux
757 Lynx 178 PowerPC powerpc-*-lynx*178
758 x86_64/Cygwin x86_64-*-cygwin*
759 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
761 * If the configured location of system.gdbinit file (as given by the
762 --with-system-gdbinit option at configure time) is in the
763 data-directory (as specified by --with-gdb-datadir at configure
764 time) or in one of its subdirectories, then GDB will look for the
765 system-wide init file in the directory specified by the
766 --data-directory command-line option.
768 * New command line options:
770 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
771 other initialization files, unlike -nx which disables all of them.
773 * Removed command line options
775 -epoch This was used by the gdb mode in Epoch, an ancient fork of
778 * The 'ptype' and 'whatis' commands now accept an argument to control
781 * 'info proc' now works on some core files.
785 ** Vectors can be created with gdb.Type.vector.
787 ** Python's atexit.register now works in GDB.
789 ** Types can be pretty-printed via a Python API.
791 ** Python 3 is now supported (in addition to Python 2.4 or later)
793 ** New class gdb.Architecture exposes GDB's internal representation
794 of architecture in the Python API.
796 ** New method Frame.architecture returns the gdb.Architecture object
797 corresponding to the frame's architecture.
799 * New Python-based convenience functions:
801 ** $_memeq(buf1, buf2, length)
802 ** $_streq(str1, str2)
804 ** $_regex(str, regex)
806 * The 'cd' command now defaults to using '~' (the home directory) if not
809 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
810 default for GCC since November 2000.
812 * The command 'forward-search' can now be abbreviated as 'fo'.
814 * The command 'info tracepoints' can now display 'installed on target'
815 or 'not installed on target' for each non-pending location of tracepoint.
817 * New configure options
819 --enable-libmcheck/--disable-libmcheck
820 By default, development versions are built with -lmcheck on hosts
821 that support it, in order to help track memory corruption issues.
822 Release versions, on the other hand, are built without -lmcheck
823 by default. The --enable-libmcheck/--disable-libmcheck configure
824 options allow the user to override that default.
825 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
826 This configure option allows the user to build GDB with
827 libbabeltrace using which GDB can read Common Trace Format data.
829 * New commands (for set/show, see "New options" below)
832 Catch signals. This is similar to "handle", but allows commands and
833 conditions to be attached.
836 List the BFDs known to GDB.
838 python-interactive [command]
840 Start a Python interactive prompt, or evaluate the optional command
841 and print the result of expressions.
844 "py" is a new alias for "python".
846 enable type-printer [name]...
847 disable type-printer [name]...
848 Enable or disable type printers.
852 ** For the Renesas Super-H architecture, the "regs" command has been removed
853 (has been deprecated in GDB 7.5), and "info all-registers" should be used
858 set print type methods (on|off)
859 show print type methods
860 Control whether method declarations are displayed by "ptype".
861 The default is to show them.
863 set print type typedefs (on|off)
864 show print type typedefs
865 Control whether typedef definitions are displayed by "ptype".
866 The default is to show them.
868 set filename-display basename|relative|absolute
869 show filename-display
870 Control the way in which filenames is displayed.
871 The default is "relative", which preserves previous behavior.
873 set trace-buffer-size
874 show trace-buffer-size
875 Request target to change the size of trace buffer.
877 set remote trace-buffer-size-packet auto|on|off
878 show remote trace-buffer-size-packet
879 Control the use of the remote protocol `QTBuffer:size' packet.
883 Control display of debugging messages related to ARM AArch64.
886 set debug coff-pe-read
887 show debug coff-pe-read
888 Control display of debugging messages related to reading of COFF/PE
893 Control display of debugging messages related to Mach-O symbols
896 set debug notification
897 show debug notification
898 Control display of debugging info for async remote notification.
902 ** Command parameter changes are now notified using new async record
903 "=cmd-param-changed".
904 ** Trace frame changes caused by command "tfind" are now notified using
905 new async record "=traceframe-changed".
906 ** The creation, deletion and modification of trace state variables
907 are now notified using new async records "=tsv-created",
908 "=tsv-deleted" and "=tsv-modified".
909 ** The start and stop of process record are now notified using new
910 async record "=record-started" and "=record-stopped".
911 ** Memory changes are now notified using new async record
913 ** The data-disassemble command response will include a "fullname" field
914 containing the absolute file name when source has been requested.
915 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
916 command, to allow pattern filling of memory areas.
917 ** New commands "-catch-load"/"-catch-unload" added for intercepting
918 library load/unload events.
919 ** The response to breakpoint commands and breakpoint async records
920 includes an "installed" field containing a boolean state about each
921 non-pending tracepoint location is whether installed on target or not.
922 ** Output of the "-trace-status" command includes a "trace-file" field
923 containing the name of the trace file being examined. This field is
924 optional, and only present when examining a trace file.
925 ** The "fullname" field is now always present along with the "file" field,
926 even if the file cannot be found by GDB.
928 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
929 You must have the LZMA library available when configuring GDB for this
930 feature to be enabled. For more information, see:
931 http://fedoraproject.org/wiki/Features/MiniDebugInfo
936 Set the size of trace buffer. The remote stub reports support for this
937 packet to gdb's qSupported query.
940 Enable Branch Trace Store (BTS)-based branch tracing for the current
941 thread. The remote stub reports support for this packet to gdb's
945 Disable branch tracing for the current thread. The remote stub reports
946 support for this packet to gdb's qSupported query.
949 Read the traced branches for the current thread. The remote stub
950 reports support for this packet to gdb's qSupported query.
952 *** Changes in GDB 7.5
954 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
955 for more x32 ABI info.
957 * GDB now supports access to MIPS DSP registers on Linux targets.
959 * GDB now supports debugging microMIPS binaries.
961 * The "info os" command on GNU/Linux can now display information on
962 several new classes of objects managed by the operating system:
963 "info os procgroups" lists process groups
964 "info os files" lists file descriptors
965 "info os sockets" lists internet-domain sockets
966 "info os shm" lists shared-memory regions
967 "info os semaphores" lists semaphores
968 "info os msg" lists message queues
969 "info os modules" lists loaded kernel modules
971 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
972 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
973 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
974 options and inspect the probe arguments using the new $_probe_arg family
975 of convenience variables. You can obtain more information about SystemTap
976 in <http://sourceware.org/systemtap/>.
978 * GDB now supports reversible debugging on ARM, it allows you to
979 debug basic ARM and THUMB instructions, and provides
980 record/replay support.
982 * The option "symbol-reloading" has been deleted as it is no longer used.
986 ** GDB commands implemented in Python can now be put in command class
989 ** The "maint set python print-stack on|off" is now deleted.
991 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
992 apply "flag enum"-style pretty-printing to any enum.
994 ** gdb.lookup_symbol can now work when there is no current frame.
996 ** gdb.Symbol now has a 'line' attribute, holding the line number in
997 the source at which the symbol was defined.
999 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1000 method 'value'. The former indicates whether the symbol needs a
1001 frame in order to compute its value, and the latter computes the
1004 ** A new method 'referenced_value' on gdb.Value objects which can
1005 dereference pointer as well as C++ reference values.
1007 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1008 which return the global and static blocks (as gdb.Block objects),
1009 of the underlying symbol table, respectively.
1011 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1012 object associated with a PC value.
1014 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1015 of the address range occupied by code for the current source line.
1017 * Go language support.
1018 GDB now supports debugging programs written in the Go programming
1021 * GDBserver now supports stdio connections.
1022 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1024 * The binary "gdbtui" can no longer be built or installed.
1025 Use "gdb -tui" instead.
1027 * GDB will now print "flag" enums specially. A flag enum is one where
1028 all the enumerator values have no bits in common when pairwise
1029 "and"ed. When printing a value whose type is a flag enum, GDB will
1030 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1031 (gdb) print (enum E) 3
1034 * The filename part of a linespec will now match trailing components
1035 of a source file name. For example, "break gcc/expr.c:1000" will
1036 now set a breakpoint in build/gcc/expr.c, but not
1037 build/libcpp/expr.c.
1039 * The "info proc" and "generate-core-file" commands will now also
1040 work on remote targets connected to GDBserver on Linux.
1042 * The command "info catch" has been removed. It has been disabled
1043 since December 2007.
1045 * The "catch exception" and "catch assert" commands now accept
1046 a condition at the end of the command, much like the "break"
1047 command does. For instance:
1049 (gdb) catch exception Constraint_Error if Barrier = True
1051 Previously, it was possible to add a condition to such catchpoints,
1052 but it had to be done as a second step, after the catchpoint had been
1053 created, using the "condition" command.
1055 * The "info static-tracepoint-marker" command will now also work on
1056 native Linux targets with in-process agent.
1058 * GDB can now set breakpoints on inlined functions.
1060 * The .gdb_index section has been updated to include symbols for
1061 inlined functions. GDB will ignore older .gdb_index sections by
1062 default, which could cause symbol files to be loaded more slowly
1063 until their .gdb_index sections can be recreated. The new command
1064 "set use-deprecated-index-sections on" will cause GDB to use any older
1065 .gdb_index sections it finds. This will restore performance, but the
1066 ability to set breakpoints on inlined functions will be lost in symbol
1067 files with older .gdb_index sections.
1069 The .gdb_index section has also been updated to record more information
1070 about each symbol. This speeds up the "info variables", "info functions"
1071 and "info types" commands when used with programs having the .gdb_index
1072 section, as well as speeding up debugging with shared libraries using
1073 the .gdb_index section.
1075 * Ada support for GDB/MI Variable Objects has been added.
1077 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1082 ** New command -info-os is the MI equivalent of "info os".
1084 ** Output logs ("set logging" and related) now include MI output.
1088 ** "set use-deprecated-index-sections on|off"
1089 "show use-deprecated-index-sections on|off"
1090 Controls the use of deprecated .gdb_index sections.
1092 ** "catch load" and "catch unload" can be used to stop when a shared
1093 library is loaded or unloaded, respectively.
1095 ** "enable count" can be used to auto-disable a breakpoint after
1098 ** "info vtbl" can be used to show the virtual method tables for
1099 C++ and Java objects.
1101 ** "explore" and its sub commands "explore value" and "explore type"
1102 can be used to recursively explore values and types of
1103 expressions. These commands are available only if GDB is
1104 configured with '--with-python'.
1106 ** "info auto-load" shows status of all kinds of auto-loaded files,
1107 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1108 sequences of commands files, "info auto-load python-scripts"
1109 shows status of auto-loading Python script files,
1110 "info auto-load local-gdbinit" shows status of loading init file
1111 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1112 status of inferior specific thread debugging shared library loading.
1114 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1115 and "show auto-load-scripts" commands have been deprecated, use their
1116 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1117 and "show auto-load python-scripts" counterparts instead.
1119 ** "dprintf location,format,args..." creates a dynamic printf, which
1120 is basically a breakpoint that does a printf and immediately
1121 resumes your program's execution, so it is like a printf that you
1122 can insert dynamically at runtime instead of at compiletime.
1124 ** "set print symbol"
1126 Controls whether GDB attempts to display the symbol, if any,
1127 corresponding to addresses it prints. This defaults to "on", but
1128 you can set it to "off" to restore GDB's previous behavior.
1130 * Deprecated commands
1132 ** For the Renesas Super-H architecture, the "regs" command has been
1133 deprecated, and "info all-registers" should be used instead.
1137 Renesas RL78 rl78-*-elf
1138 HP OpenVMS ia64 ia64-hp-openvms*
1140 * GDBserver supports evaluation of breakpoint conditions. When
1141 support is advertised by GDBserver, GDB may be told to send the
1142 breakpoint conditions in bytecode form to GDBserver. GDBserver
1143 will only report the breakpoint trigger to GDB when its condition
1148 set mips compression
1149 show mips compression
1150 Select the compressed ISA encoding used in functions that have no symbol
1151 information available. The encoding can be set to either of:
1154 and is updated automatically from ELF file flags if available.
1156 set breakpoint condition-evaluation
1157 show breakpoint condition-evaluation
1158 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1159 GDBserver ("target"). Default option "auto" chooses the most efficient
1161 This option can improve debugger efficiency depending on the speed of the
1165 Disable auto-loading globally.
1168 Show auto-loading setting of all kinds of auto-loaded files.
1170 set auto-load gdb-scripts on|off
1171 show auto-load gdb-scripts
1172 Control auto-loading of GDB canned sequences of commands files.
1174 set auto-load python-scripts on|off
1175 show auto-load python-scripts
1176 Control auto-loading of Python script files.
1178 set auto-load local-gdbinit on|off
1179 show auto-load local-gdbinit
1180 Control loading of init file (.gdbinit) from current directory.
1182 set auto-load libthread-db on|off
1183 show auto-load libthread-db
1184 Control auto-loading of inferior specific thread debugging shared library.
1186 set auto-load scripts-directory <dir1>[:<dir2>...]
1187 show auto-load scripts-directory
1188 Set a list of directories from which to load auto-loaded scripts.
1189 Automatically loaded Python scripts and GDB scripts are located in one
1190 of the directories listed by this option.
1191 The delimiter (':' above) may differ according to the host platform.
1193 set auto-load safe-path <dir1>[:<dir2>...]
1194 show auto-load safe-path
1195 Set a list of directories from which it is safe to auto-load files.
1196 The delimiter (':' above) may differ according to the host platform.
1198 set debug auto-load on|off
1199 show debug auto-load
1200 Control display of debugging info for auto-loading the files above.
1202 set dprintf-style gdb|call|agent
1204 Control the way in which a dynamic printf is performed; "gdb"
1205 requests a GDB printf command, while "call" causes dprintf to call a
1206 function in the inferior. "agent" requests that the target agent
1207 (such as GDBserver) do the printing.
1209 set dprintf-function <expr>
1210 show dprintf-function
1211 set dprintf-channel <expr>
1212 show dprintf-channel
1213 Set the function and optional first argument to the call when using
1214 the "call" style of dynamic printf.
1216 set disconnected-dprintf on|off
1217 show disconnected-dprintf
1218 Control whether agent-style dynamic printfs continue to be in effect
1219 after GDB disconnects.
1221 * New configure options
1223 --with-auto-load-dir
1224 Configure default value for the 'set auto-load scripts-directory'
1225 setting above. It defaults to '$debugdir:$datadir/auto-load',
1226 $debugdir representing global debugging info directories (available
1227 via 'show debug-file-directory') and $datadir representing GDB's data
1228 directory (available via 'show data-directory').
1230 --with-auto-load-safe-path
1231 Configure default value for the 'set auto-load safe-path' setting
1232 above. It defaults to the --with-auto-load-dir setting.
1234 --without-auto-load-safe-path
1235 Set 'set auto-load safe-path' to '/', effectively disabling this
1238 * New remote packets
1240 z0/z1 conditional breakpoints extension
1242 The z0/z1 breakpoint insertion packets have been extended to carry
1243 a list of conditional expressions over to the remote stub depending on the
1244 condition evaluation mode. The use of this extension can be controlled
1245 via the "set remote conditional-breakpoints-packet" command.
1249 Specify the signals which the remote stub may pass to the debugged
1250 program without GDB involvement.
1252 * New command line options
1254 --init-command=FILE, -ix Like --command, -x but execute it
1255 before loading inferior.
1256 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1257 execute it before loading inferior.
1259 *** Changes in GDB 7.4
1261 * GDB now handles ambiguous linespecs more consistently; the existing
1262 FILE:LINE support has been expanded to other types of linespecs. A
1263 breakpoint will now be set on all matching locations in all
1264 inferiors, and locations will be added or removed according to
1267 * GDB now allows you to skip uninteresting functions and files when
1268 stepping with the "skip function" and "skip file" commands.
1270 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1271 and "show remote hardware-watchpoint-length-limit". These allows to
1272 set or show the maximum length limit (in bytes) of a remote
1273 target hardware watchpoint.
1275 This allows e.g. to use "unlimited" hardware watchpoints with the
1276 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1277 watchpoints are slower than real hardware watchpoints but are
1278 significantly faster than gdb software watchpoints.
1282 ** The register_pretty_printer function in module gdb.printing now takes
1283 an optional `replace' argument. If True, the new printer replaces any
1286 ** The "maint set python print-stack on|off" command has been
1287 deprecated and will be deleted in GDB 7.5.
1288 A new command: "set python print-stack none|full|message" has
1289 replaced it. Additionally, the default for "print-stack" is
1290 now "message", which just prints the error message without
1293 ** A prompt substitution hook (prompt_hook) is now available to the
1296 ** A new Python module, gdb.prompt has been added to the GDB Python
1297 modules library. This module provides functionality for
1298 escape sequences in prompts (used by set/show
1299 extended-prompt). These escape sequences are replaced by their
1300 corresponding value.
1302 ** Python commands and convenience-functions located in
1303 'data-directory'/python/gdb/command and
1304 'data-directory'/python/gdb/function are now automatically loaded
1307 ** Blocks now provide four new attributes. global_block and
1308 static_block will return the global and static blocks
1309 respectively. is_static and is_global are boolean attributes
1310 that indicate if the block is one of those two types.
1312 ** Symbols now provide the "type" attribute, the type of the symbol.
1314 ** The "gdb.breakpoint" function has been deprecated in favor of
1317 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1318 of a function. This class is based on the "finish" command
1319 available in the CLI.
1321 ** Type objects for struct and union types now allow access to
1322 the fields using standard Python dictionary (mapping) methods.
1323 For example, "some_type['myfield']" now works, as does
1324 "some_type.items()".
1326 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1329 ** A new function, "deep_items" has been added to the gdb.types
1330 module in the GDB Python modules library. This function returns
1331 an iterator over the fields of a struct or union type. Unlike
1332 the standard Python "iteritems" method, it will recursively traverse
1333 any anonymous fields.
1337 ** "*stopped" events can report several new "reason"s, such as
1340 ** Breakpoint changes are now notified using new async records, like
1341 "=breakpoint-modified".
1343 ** New command -ada-task-info.
1345 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1346 $sdir specifies the default system locations of shared libraries.
1347 $pdir specifies the directory where the libpthread used by the application
1350 GDB no longer looks in $sdir and $pdir after it has searched the directories
1351 mentioned in libthread-db-search-path. If you want to search those
1352 directories, they must be specified in libthread-db-search-path.
1353 The default value of libthread-db-search-path on GNU/Linux and Solaris
1354 systems is now "$sdir:$pdir".
1356 $pdir is not supported by gdbserver, it is currently ignored.
1357 $sdir is supported by gdbserver.
1359 * New configure option --with-iconv-bin.
1360 When using the internationalization support like the one in the GNU C
1361 library, GDB will invoke the "iconv" program to get a list of supported
1362 character sets. If this program lives in a non-standard location, one can
1363 use this option to specify where to find it.
1365 * When natively debugging programs on PowerPC BookE processors running
1366 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1367 watchpoints, which specify a mask in addition to an address to watch.
1368 The mask specifies that some bits of an address (the bits which are
1369 reset in the mask) should be ignored when matching the address accessed
1370 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1371 section in the user manual for more details.
1373 * The new option --once causes GDBserver to stop listening for connections once
1374 the first connection is made. The listening port used by GDBserver will
1375 become available after that.
1377 * New commands "info macros" and "alias" have been added.
1379 * New function parameters suffix @entry specifies value of function parameter
1380 at the time the function got called. Entry values are available only since
1386 "!" is now an alias of the "shell" command.
1387 Note that no space is needed between "!" and SHELL COMMAND.
1391 watch EXPRESSION mask MASK_VALUE
1392 The watch command now supports the mask argument which allows creation
1393 of masked watchpoints, if the current architecture supports this feature.
1395 info auto-load-scripts [REGEXP]
1396 This command was formerly named "maintenance print section-scripts".
1397 It is now generally useful and is no longer a maintenance-only command.
1399 info macro [-all] [--] MACRO
1400 The info macro command has new options `-all' and `--'. The first for
1401 printing all definitions of a macro. The second for explicitly specifying
1402 the end of arguments and the beginning of the macro name in case the macro
1403 name starts with a hyphen.
1405 collect[/s] EXPRESSIONS
1406 The tracepoint collect command now takes an optional modifier "/s"
1407 that directs it to dereference pointer-to-character types and
1408 collect the bytes of memory up to a zero byte. The behavior is
1409 similar to what you see when you use the regular print command on a
1410 string. An optional integer following the "/s" sets a bound on the
1411 number of bytes that will be collected.
1414 The trace start command now interprets any supplied arguments as a
1415 note to be recorded with the trace run, with an effect similar to
1416 setting the variable trace-notes.
1419 The trace stop command now interprets any arguments as a note to be
1420 mentioned along with the tstatus report that the trace was stopped
1421 with a command. The effect is similar to setting the variable
1424 * Tracepoints can now be enabled and disabled at any time after a trace
1425 experiment has been started using the standard "enable" and "disable"
1426 commands. It is now possible to start a trace experiment with no enabled
1427 tracepoints; GDB will display a warning, but will allow the experiment to
1428 begin, assuming that tracepoints will be enabled as needed while the trace
1431 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1432 locations with 4-byte instructions, when they were previously
1433 limited to locations with instructions of 5 bytes or longer.
1437 set debug dwarf2-read
1438 show debug dwarf2-read
1439 Turns on or off display of debugging messages related to reading
1440 DWARF debug info. The default is off.
1442 set debug symtab-create
1443 show debug symtab-create
1444 Turns on or off display of debugging messages related to symbol table
1445 creation. The default is off.
1448 show extended-prompt
1449 Set the GDB prompt, and allow escape sequences to be inserted to
1450 display miscellaneous information (see 'help set extended-prompt'
1451 for the list of sequences). This prompt (and any information
1452 accessed through the escape sequences) is updated every time the
1453 prompt is displayed.
1455 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1456 show print entry-values
1457 Set printing of frame argument values at function entry. In some cases
1458 GDB can determine the value of function argument which was passed by the
1459 function caller, even if the value was modified inside the called function.
1461 set debug entry-values
1462 show debug entry-values
1463 Control display of debugging info for determining frame argument values at
1464 function entry and virtual tail call frames.
1466 set basenames-may-differ
1467 show basenames-may-differ
1468 Set whether a source file may have multiple base names.
1469 (A "base name" is the name of a file with the directory part removed.
1470 Example: The base name of "/home/user/hello.c" is "hello.c".)
1471 If set, GDB will canonicalize file names (e.g., expand symlinks)
1472 before comparing them. Canonicalization is an expensive operation,
1473 but it allows the same file be known by more than one base name.
1474 If not set (the default), all source files are assumed to have just
1475 one base name, and gdb will do file name comparisons more efficiently.
1481 Set a user name and notes for the current and any future trace runs.
1482 This is useful for long-running and/or disconnected traces, to
1483 inform others (or yourself) as to who is running the trace, supply
1484 contact information, or otherwise explain what is going on.
1486 set trace-stop-notes
1487 show trace-stop-notes
1488 Set a note attached to the trace run, that is displayed when the
1489 trace has been stopped by a tstop command. This is useful for
1490 instance as an explanation, if you are stopping a trace run that was
1491 started by someone else.
1493 * New remote packets
1497 Dynamically enable a tracepoint in a started trace experiment.
1501 Dynamically disable a tracepoint in a started trace experiment.
1505 Set the user and notes of the trace run.
1509 Query the current status of a tracepoint.
1513 Query the minimum length of instruction at which a fast tracepoint may
1516 * Dcache size (number of lines) and line-size are now runtime-configurable
1517 via "set dcache line" and "set dcache line-size" commands.
1521 Texas Instruments TMS320C6x tic6x-*-*
1525 Renesas RL78 rl78-*-elf
1527 *** Changes in GDB 7.3.1
1529 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1531 *** Changes in GDB 7.3
1533 * GDB has a new command: "thread find [REGEXP]".
1534 It finds the thread id whose name, target id, or thread extra info
1535 matches the given regular expression.
1537 * The "catch syscall" command now works on mips*-linux* targets.
1539 * The -data-disassemble MI command now supports modes 2 and 3 for
1540 dumping the instruction opcodes.
1542 * New command line options
1544 -data-directory DIR Specify DIR as the "data-directory".
1545 This is mostly for testing purposes.
1547 * The "maint set python auto-load on|off" command has been renamed to
1548 "set auto-load-scripts on|off".
1550 * GDB has a new command: "set directories".
1551 It is like the "dir" command except that it replaces the
1552 source path list instead of augmenting it.
1554 * GDB now understands thread names.
1556 On GNU/Linux, "info threads" will display the thread name as set by
1557 prctl or pthread_setname_np.
1559 There is also a new command, "thread name", which can be used to
1560 assign a name internally for GDB to display.
1563 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1564 has been integrated into GDB.
1568 ** The function gdb.Write now accepts an optional keyword 'stream'.
1569 This keyword, when provided, will direct the output to either
1570 stdout, stderr, or GDB's logging output.
1572 ** Parameters can now be be sub-classed in Python, and in particular
1573 you may implement the get_set_doc and get_show_doc functions.
1574 This improves how Parameter set/show documentation is processed
1575 and allows for more dynamic content.
1577 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1578 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1579 have an is_valid method.
1581 ** Breakpoints can now be sub-classed in Python, and in particular
1582 you may implement a 'stop' function that is executed each time
1583 the inferior reaches that breakpoint.
1585 ** New function gdb.lookup_global_symbol looks up a global symbol.
1587 ** GDB values in Python are now callable if the value represents a
1588 function. For example, if 'some_value' represents a function that
1589 takes two integer parameters and returns a value, you can call
1590 that function like so:
1592 result = some_value (10,20)
1594 ** Module gdb.types has been added.
1595 It contains a collection of utilities for working with gdb.Types objects:
1596 get_basic_type, has_field, make_enum_dict.
1598 ** Module gdb.printing has been added.
1599 It contains utilities for writing and registering pretty-printers.
1600 New classes: PrettyPrinter, SubPrettyPrinter,
1601 RegexpCollectionPrettyPrinter.
1602 New function: register_pretty_printer.
1604 ** New commands "info pretty-printers", "enable pretty-printer" and
1605 "disable pretty-printer" have been added.
1607 ** gdb.parameter("directories") is now available.
1609 ** New function gdb.newest_frame returns the newest frame in the
1612 ** The gdb.InferiorThread class has a new "name" attribute. This
1613 holds the thread's name.
1615 ** Python Support for Inferior events.
1616 Python scripts can add observers to be notified of events
1617 occurring in the process being debugged.
1618 The following events are currently supported:
1619 - gdb.events.cont Continue event.
1620 - gdb.events.exited Inferior exited event.
1621 - gdb.events.stop Signal received, and Breakpoint hit events.
1625 ** GDB now puts template parameters in scope when debugging in an
1626 instantiation. For example, if you have:
1628 template<int X> int func (void) { return X; }
1630 then if you step into func<5>, "print X" will show "5". This
1631 feature requires proper debuginfo support from the compiler; it
1632 was added to GCC 4.5.
1634 ** The motion commands "next", "finish", "until", and "advance" now
1635 work better when exceptions are thrown. In particular, GDB will
1636 no longer lose control of the inferior; instead, the GDB will
1637 stop the inferior at the point at which the exception is caught.
1638 This functionality requires a change in the exception handling
1639 code that was introduced in GCC 4.5.
1641 * GDB now follows GCC's rules on accessing volatile objects when
1642 reading or writing target state during expression evaluation.
1643 One notable difference to prior behavior is that "print x = 0"
1644 no longer generates a read of x; the value of the assignment is
1645 now always taken directly from the value being assigned.
1647 * GDB now has some support for using labels in the program's source in
1648 linespecs. For instance, you can use "advance label" to continue
1649 execution to a label.
1651 * GDB now has support for reading and writing a new .gdb_index
1652 section. This section holds a fast index of DWARF debugging
1653 information and can be used to greatly speed up GDB startup and
1654 operation. See the documentation for `save gdb-index' for details.
1656 * The "watch" command now accepts an optional "-location" argument.
1657 When used, this causes GDB to watch the memory referred to by the
1658 expression. Such a watchpoint is never deleted due to it going out
1661 * GDB now supports thread debugging of core dumps on GNU/Linux.
1663 GDB now activates thread debugging using the libthread_db library
1664 when debugging GNU/Linux core dumps, similarly to when debugging
1665 live processes. As a result, when debugging a core dump file, GDB
1666 is now able to display pthread_t ids of threads. For example, "info
1667 threads" shows the same output as when debugging the process when it
1668 was live. In earlier releases, you'd see something like this:
1671 * 1 LWP 6780 main () at main.c:10
1673 While now you see this:
1676 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1678 It is also now possible to inspect TLS variables when debugging core
1681 When debugging a core dump generated on a machine other than the one
1682 used to run GDB, you may need to point GDB at the correct
1683 libthread_db library with the "set libthread-db-search-path"
1684 command. See the user manual for more details on this command.
1686 * When natively debugging programs on PowerPC BookE processors running
1687 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1688 which stop execution of the inferior whenever it executes an instruction
1689 at any address within the specified range. See the "PowerPC Embedded"
1690 section in the user manual for more details.
1692 * New features in the GDB remote stub, GDBserver
1694 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1695 and i686 LynxOS (version 5.x).
1697 ** GDBserver is now supported on Blackfin Linux.
1699 * New native configurations
1701 ia64 HP-UX ia64-*-hpux*
1705 Analog Devices, Inc. Blackfin Processor bfin-*
1707 * Ada task switching is now supported on sparc-elf targets when
1708 debugging a program using the Ravenscar Profile. For more information,
1709 see the "Tasking Support when using the Ravenscar Profile" section
1710 in the GDB user manual.
1712 * Guile support was removed.
1714 * New features in the GNU simulator
1716 ** The --map-info flag lists all known core mappings.
1718 ** CFI flashes may be simulated via the "cfi" device.
1720 *** Changes in GDB 7.2
1722 * Shared library support for remote targets by default
1724 When GDB is configured for a generic, non-OS specific target, like
1725 for example, --target=arm-eabi or one of the many *-*-elf targets,
1726 GDB now queries remote stubs for loaded shared libraries using the
1727 `qXfer:libraries:read' packet. Previously, shared library support
1728 was always disabled for such configurations.
1732 ** Argument Dependent Lookup (ADL)
1734 In C++ ADL lookup directs function search to the namespaces of its
1735 arguments even if the namespace has not been imported.
1745 Here the compiler will search for `foo' in the namespace of 'b'
1746 and find A::foo. GDB now supports this. This construct is commonly
1747 used in the Standard Template Library for operators.
1749 ** Improved User Defined Operator Support
1751 In addition to member operators, GDB now supports lookup of operators
1752 defined in a namespace and imported with a `using' directive, operators
1753 defined in the global scope, operators imported implicitly from an
1754 anonymous namespace, and the ADL operators mentioned in the previous
1756 GDB now also supports proper overload resolution for all the previously
1757 mentioned flavors of operators.
1759 ** static const class members
1761 Printing of static const class members that are initialized in the
1762 class definition has been fixed.
1764 * Windows Thread Information Block access.
1766 On Windows targets, GDB now supports displaying the Windows Thread
1767 Information Block (TIB) structure. This structure is visible either
1768 by using the new command `info w32 thread-information-block' or, by
1769 dereferencing the new convenience variable named `$_tlb', a
1770 thread-specific pointer to the TIB. This feature is also supported
1771 when remote debugging using GDBserver.
1773 * Static tracepoints
1775 Static tracepoints are calls in the user program into a tracing
1776 library. One such library is a port of the LTTng kernel tracer to
1777 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1778 When debugging with GDBserver, GDB now supports combining the GDB
1779 tracepoint machinery with such libraries. For example: the user can
1780 use GDB to probe a static tracepoint marker (a call from the user
1781 program into the tracing library) with the new "strace" command (see
1782 "New commands" below). This creates a "static tracepoint" in the
1783 breakpoint list, that can be manipulated with the same feature set
1784 as fast and regular tracepoints. E.g., collect registers, local and
1785 global variables, collect trace state variables, and define
1786 tracepoint conditions. In addition, the user can collect extra
1787 static tracepoint marker specific data, by collecting the new
1788 $_sdata internal variable. When analyzing the trace buffer, you can
1789 inspect $_sdata like any other variable available to GDB. For more
1790 information, see the "Tracepoints" chapter in GDB user manual. New
1791 remote packets have been defined to support static tracepoints, see
1792 the "New remote packets" section below.
1794 * Better reconstruction of tracepoints after disconnected tracing
1796 GDB will attempt to download the original source form of tracepoint
1797 definitions when starting a trace run, and then will upload these
1798 upon reconnection to the target, resulting in a more accurate
1799 reconstruction of the tracepoints that are in use on the target.
1803 You can now exercise direct control over the ways that GDB can
1804 affect your program. For instance, you can disallow the setting of
1805 breakpoints, so that the program can run continuously (assuming
1806 non-stop mode). In addition, the "observer" variable is available
1807 to switch all of the different controls; in observer mode, GDB
1808 cannot affect the target's behavior at all, which is useful for
1809 tasks like diagnosing live systems in the field.
1811 * The new convenience variable $_thread holds the number of the
1814 * New remote packets
1818 Return the address of the Windows Thread Information Block of a given thread.
1822 In response to several of the tracepoint packets, the target may now
1823 also respond with a number of intermediate `qRelocInsn' request
1824 packets before the final result packet, to have GDB handle
1825 relocating an instruction to execute at a different address. This
1826 is particularly useful for stubs that support fast tracepoints. GDB
1827 reports support for this feature in the qSupported packet.
1831 List static tracepoint markers in the target program.
1835 List static tracepoint markers at a given address in the target
1838 qXfer:statictrace:read
1840 Read the static trace data collected (by a `collect $_sdata'
1841 tracepoint action). The remote stub reports support for this packet
1842 to gdb's qSupported query.
1846 Send the current settings of GDB's permission flags.
1850 Send part of the source (textual) form of a tracepoint definition,
1851 which includes location, conditional, and action list.
1853 * The source command now accepts a -s option to force searching for the
1854 script in the source search path even if the script name specifies
1857 * New features in the GDB remote stub, GDBserver
1859 - GDBserver now support tracepoints (including fast tracepoints, and
1860 static tracepoints). The feature is currently supported by the
1861 i386-linux and amd64-linux builds. See the "Tracepoints support
1862 in gdbserver" section in the manual for more information.
1864 GDBserver JIT compiles the tracepoint's conditional agent
1865 expression bytecode into native code whenever possible for low
1866 overhead dynamic tracepoints conditionals. For such tracepoints,
1867 an expression that examines program state is evaluated when the
1868 tracepoint is reached, in order to determine whether to capture
1869 trace data. If the condition is simple and false, processing the
1870 tracepoint finishes very quickly and no data is gathered.
1872 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1873 for static tracepoints support.
1875 - GDBserver now supports x86_64 Windows 64-bit debugging.
1877 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1878 it understands register description.
1880 * The --batch flag now disables pagination and queries.
1882 * X86 general purpose registers
1884 GDB now supports reading/writing byte, word and double-word x86
1885 general purpose registers directly. This means you can use, say,
1886 $ah or $ax to refer, respectively, to the byte register AH and
1887 16-bit word register AX that are actually portions of the 32-bit
1888 register EAX or 64-bit register RAX.
1890 * The `commands' command now accepts a range of breakpoints to modify.
1891 A plain `commands' following a command that creates multiple
1892 breakpoints affects all the breakpoints set by that command. This
1893 applies to breakpoints set by `rbreak', and also applies when a
1894 single `break' command creates multiple breakpoints (e.g.,
1895 breakpoints on overloaded c++ functions).
1897 * The `rbreak' command now accepts a filename specification as part of
1898 its argument, limiting the functions selected by the regex to those
1899 in the specified file.
1901 * Support for remote debugging Windows and SymbianOS shared libraries
1902 from Unix hosts has been improved. Non Windows GDB builds now can
1903 understand target reported file names that follow MS-DOS based file
1904 system semantics, such as file names that include drive letters and
1905 use the backslash character as directory separator. This makes it
1906 possible to transparently use the "set sysroot" and "set
1907 solib-search-path" on Unix hosts to point as host copies of the
1908 target's shared libraries. See the new command "set
1909 target-file-system-kind" described below, and the "Commands to
1910 specify files" section in the user manual for more information.
1914 eval template, expressions...
1915 Convert the values of one or more expressions under the control
1916 of the string template to a command line, and call it.
1918 set target-file-system-kind unix|dos-based|auto
1919 show target-file-system-kind
1920 Set or show the assumed file system kind for target reported file
1923 save breakpoints <filename>
1924 Save all current breakpoint definitions to a file suitable for use
1925 in a later debugging session. To read the saved breakpoint
1926 definitions, use the `source' command.
1928 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1931 info static-tracepoint-markers
1932 Display information about static tracepoint markers in the target.
1934 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1935 Define a static tracepoint by probing a marker at the given
1936 function, line, address, or marker ID.
1940 Enable and disable observer mode.
1942 set may-write-registers on|off
1943 set may-write-memory on|off
1944 set may-insert-breakpoints on|off
1945 set may-insert-tracepoints on|off
1946 set may-insert-fast-tracepoints on|off
1947 set may-interrupt on|off
1948 Set individual permissions for GDB effects on the target. Note that
1949 some of these settings can have undesirable or surprising
1950 consequences, particularly when changed in the middle of a session.
1951 For instance, disabling the writing of memory can prevent
1952 breakpoints from being inserted, cause single-stepping to fail, or
1953 even crash your program, if you disable after breakpoints have been
1954 inserted. However, GDB should not crash.
1956 set record memory-query on|off
1957 show record memory-query
1958 Control whether to stop the inferior if memory changes caused
1959 by an instruction cannot be recorded.
1964 The disassemble command now supports "start,+length" form of two arguments.
1968 ** GDB now provides a new directory location, called the python directory,
1969 where Python scripts written for GDB can be installed. The location
1970 of that directory is <data-directory>/python, where <data-directory>
1971 is the GDB data directory. For more details, see section `Scripting
1972 GDB using Python' in the manual.
1974 ** The GDB Python API now has access to breakpoints, symbols, symbol
1975 tables, program spaces, inferiors, threads and frame's code blocks.
1976 Additionally, GDB Parameters can now be created from the API, and
1977 manipulated via set/show in the CLI.
1979 ** New functions gdb.target_charset, gdb.target_wide_charset,
1980 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1982 ** New exception gdb.GdbError.
1984 ** Pretty-printers are now also looked up in the current program space.
1986 ** Pretty-printers can now be individually enabled and disabled.
1988 ** GDB now looks for names of Python scripts to auto-load in a
1989 special section named `.debug_gdb_scripts', in addition to looking
1990 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1992 * Tracepoint actions were unified with breakpoint commands. In particular,
1993 there are no longer differences in "info break" output for breakpoints and
1994 tracepoints and the "commands" command can be used for both tracepoints and
1995 regular breakpoints.
1999 ARM Symbian arm*-*-symbianelf*
2001 * D language support.
2002 GDB now supports debugging programs written in the D programming
2005 * GDB now supports the extended ptrace interface for PowerPC which is
2006 available since Linux kernel version 2.6.34. This automatically enables
2007 any hardware breakpoints and additional hardware watchpoints available in
2008 the processor. The old ptrace interface exposes just one hardware
2009 watchpoint and no hardware breakpoints.
2011 * GDB is now able to use the Data Value Compare (DVC) register available on
2012 embedded PowerPC processors to implement in hardware simple watchpoint
2013 conditions of the form:
2015 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2017 This works in native GDB running on Linux kernels with the extended ptrace
2018 interface mentioned above.
2020 *** Changes in GDB 7.1
2024 ** Namespace Support
2026 GDB now supports importing of namespaces in C++. This enables the
2027 user to inspect variables from imported namespaces. Support for
2028 namepace aliasing has also been added. So, if a namespace is
2029 aliased in the current scope (e.g. namepace C=A; ) the user can
2030 print variables using the alias (e.g. (gdb) print C::x).
2034 All known bugs relating to the printing of virtual base class were
2035 fixed. It is now possible to call overloaded static methods using a
2040 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2041 and reinterpret_cast<> are now handled by the C++ expression parser.
2045 Xilinx MicroBlaze microblaze-*-*
2050 Xilinx MicroBlaze microblaze
2053 * Multi-program debugging.
2055 GDB now has support for multi-program (a.k.a. multi-executable or
2056 multi-exec) debugging. This allows for debugging multiple inferiors
2057 simultaneously each running a different program under the same GDB
2058 session. See "Debugging Multiple Inferiors and Programs" in the
2059 manual for more information. This implied some user visible changes
2060 in the multi-inferior support. For example, "info inferiors" now
2061 lists inferiors that are not running yet or that have exited
2062 already. See also "New commands" and "New options" below.
2064 * New tracing features
2066 GDB's tracepoint facility now includes several new features:
2068 ** Trace state variables
2070 GDB tracepoints now include support for trace state variables, which
2071 are variables managed by the target agent during a tracing
2072 experiment. They are useful for tracepoints that trigger each
2073 other, so for instance one tracepoint can count hits in a variable,
2074 and then a second tracepoint has a condition that is true when the
2075 count reaches a particular value. Trace state variables share the
2076 $-syntax of GDB convenience variables, and can appear in both
2077 tracepoint actions and condition expressions. Use the "tvariable"
2078 command to create, and "info tvariables" to view; see "Trace State
2079 Variables" in the manual for more detail.
2083 GDB now includes an option for defining fast tracepoints, which
2084 targets may implement more efficiently, such as by installing a jump
2085 into the target agent rather than a trap instruction. The resulting
2086 speedup can be by two orders of magnitude or more, although the
2087 tradeoff is that some program locations on some target architectures
2088 might not allow fast tracepoint installation, for instance if the
2089 instruction to be replaced is shorter than the jump. To request a
2090 fast tracepoint, use the "ftrace" command, with syntax identical to
2091 the regular trace command.
2093 ** Disconnected tracing
2095 It is now possible to detach GDB from the target while it is running
2096 a trace experiment, then reconnect later to see how the experiment
2097 is going. In addition, a new variable disconnected-tracing lets you
2098 tell the target agent whether to continue running a trace if the
2099 connection is lost unexpectedly.
2103 GDB now has the ability to save the trace buffer into a file, and
2104 then use that file as a target, similarly to you can do with
2105 corefiles. You can select trace frames, print data that was
2106 collected in them, and use tstatus to display the state of the
2107 tracing run at the moment that it was saved. To create a trace
2108 file, use "tsave <filename>", and to use it, do "target tfile
2111 ** Circular trace buffer
2113 You can ask the target agent to handle the trace buffer as a
2114 circular buffer, discarding the oldest trace frames to make room for
2115 newer ones, by setting circular-trace-buffer to on. This feature may
2116 not be available for all target agents.
2121 The disassemble command, when invoked with two arguments, now requires
2122 the arguments to be comma-separated.
2125 The info variables command now displays variable definitions. Files
2126 which only declare a variable are not shown.
2129 The source command is now capable of sourcing Python scripts.
2130 This feature is dependent on the debugger being build with Python
2133 Related to this enhancement is also the introduction of a new command
2134 "set script-extension" (see below).
2136 * New commands (for set/show, see "New options" below)
2138 record save [<FILENAME>]
2139 Save a file (in core file format) containing the process record
2140 execution log for replay debugging at a later time.
2142 record restore <FILENAME>
2143 Restore the process record execution log that was saved at an
2144 earlier time, for replay debugging.
2146 add-inferior [-copies <N>] [-exec <FILENAME>]
2149 clone-inferior [-copies <N>] [ID]
2150 Make a new inferior ready to execute the same program another
2151 inferior has loaded.
2156 maint info program-spaces
2157 List the program spaces loaded into GDB.
2159 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2160 show remote interrupt-sequence
2161 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2162 as the sequence to the remote target in order to interrupt the execution.
2163 Ctrl-C is a default. Some system prefers BREAK which is high level of
2164 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2165 Magic SysRq g. It is BREAK signal and character 'g'.
2167 set remote interrupt-on-connect [on | off]
2168 show remote interrupt-on-connect
2169 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2170 remote target when gdb connects to it. This is needed when you debug
2173 set remotebreak [on | off]
2175 Deprecated. Use "set/show remote interrupt-sequence" instead.
2177 tvariable $NAME [ = EXP ]
2178 Create or modify a trace state variable.
2181 List trace state variables and their values.
2183 delete tvariable $NAME ...
2184 Delete one or more trace state variables.
2187 Evaluate the given expressions without collecting anything into the
2188 trace buffer. (Valid in tracepoint actions only.)
2190 ftrace FN / FILE:LINE / *ADDR
2191 Define a fast tracepoint at the given function, line, or address.
2193 * New expression syntax
2195 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2196 GDB now parses 0b101010 identically with 42.
2200 set follow-exec-mode new|same
2201 show follow-exec-mode
2202 Control whether GDB reuses the same inferior across an exec call or
2203 creates a new one. This is useful to be able to restart the old
2204 executable after the inferior having done an exec call.
2206 set default-collect EXPR, ...
2207 show default-collect
2208 Define a list of expressions to be collected at each tracepoint.
2209 This is a useful way to ensure essential items are not overlooked,
2210 such as registers or a critical global variable.
2212 set disconnected-tracing
2213 show disconnected-tracing
2214 If set to 1, the target is instructed to continue tracing if it
2215 loses its connection to GDB. If 0, the target is to stop tracing
2218 set circular-trace-buffer
2219 show circular-trace-buffer
2220 If set to on, the target is instructed to use a circular trace buffer
2221 and discard the oldest trace frames instead of stopping the trace due
2222 to a full trace buffer. If set to off, the trace stops when the buffer
2223 fills up. Some targets may not support this.
2225 set script-extension off|soft|strict
2226 show script-extension
2227 If set to "off", the debugger does not perform any script language
2228 recognition, and all sourced files are assumed to be GDB scripts.
2229 If set to "soft" (the default), files are sourced according to
2230 filename extension, falling back to GDB scripts if the first
2232 If set to "strict", files are sourced according to filename extension.
2234 set ada trust-PAD-over-XVS on|off
2235 show ada trust-PAD-over-XVS
2236 If off, activate a workaround against a bug in the debugging information
2237 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2238 the GCC sources for more information about the GNAT encoding and
2239 PAD types in particular). It is always safe to set this option to
2240 off, but this introduces a slight performance penalty. The default
2243 * Python API Improvements
2245 ** GDB provides the new class gdb.LazyString. This is useful in
2246 some pretty-printing cases. The new method gdb.Value.lazy_string
2247 provides a simple way to create objects of this type.
2249 ** The fields returned by gdb.Type.fields now have an
2250 `is_base_class' attribute.
2252 ** The new method gdb.Type.range returns the range of an array type.
2254 ** The new method gdb.parse_and_eval can be used to parse and
2255 evaluate an expression.
2257 * New remote packets
2260 Define a trace state variable.
2263 Get the current value of a trace state variable.
2266 Set desired tracing behavior upon disconnection.
2269 Set the trace buffer to be linear or circular.
2272 Get data about the tracepoints currently in use.
2276 Process record now works correctly with hardware watchpoints.
2278 Multiple bug fixes have been made to the mips-irix port, making it
2279 much more reliable. In particular:
2280 - Debugging threaded applications is now possible again. Previously,
2281 GDB would hang while starting the program, or while waiting for
2282 the program to stop at a breakpoint.
2283 - Attaching to a running process no longer hangs.
2284 - An error occurring while loading a core file has been fixed.
2285 - Changing the value of the PC register now works again. This fixes
2286 problems observed when using the "jump" command, or when calling
2287 a function from GDB, or even when assigning a new value to $pc.
2288 - With the "finish" and "return" commands, the return value for functions
2289 returning a small array is now correctly printed.
2290 - It is now possible to break on shared library code which gets executed
2291 during a shared library init phase (code executed while executing
2292 their .init section). Previously, the breakpoint would have no effect.
2293 - GDB is now able to backtrace through the signal handler for
2294 non-threaded programs.
2296 PIE (Position Independent Executable) programs debugging is now supported.
2297 This includes debugging execution of PIC (Position Independent Code) shared
2298 libraries although for that, it should be possible to run such libraries as an
2301 *** Changes in GDB 7.0
2303 * GDB now has an interface for JIT compilation. Applications that
2304 dynamically generate code can create symbol files in memory and register
2305 them with GDB. For users, the feature should work transparently, and
2306 for JIT developers, the interface is documented in the GDB manual in the
2307 "JIT Compilation Interface" chapter.
2309 * Tracepoints may now be conditional. The syntax is as for
2310 breakpoints; either an "if" clause appended to the "trace" command,
2311 or the "condition" command is available. GDB sends the condition to
2312 the target for evaluation using the same bytecode format as is used
2313 for tracepoint actions.
2315 * The disassemble command now supports: an optional /r modifier, print the
2316 raw instructions in hex as well as in symbolic form, and an optional /m
2317 modifier to print mixed source+assembly.
2319 * Process record and replay
2321 In a architecture environment that supports ``process record and
2322 replay'', ``process record and replay'' target can record a log of
2323 the process execution, and replay it with both forward and reverse
2326 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2327 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2328 set execution-direction {forward|reverse}, for targets that support
2331 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2332 feature is available with a native GDB running on kernel version
2335 * GDB now has support for multi-byte and wide character sets on the
2336 target. Strings whose character type is wchar_t, char16_t, or
2337 char32_t are now correctly printed. GDB supports wide- and unicode-
2338 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2339 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2340 `printf'. This feature requires iconv to work properly; if your
2341 system does not have a working iconv, GDB can use GNU libiconv. See
2342 the installation instructions for more information.
2344 * GDB now supports automatic retrieval of shared library files from
2345 remote targets. To use this feature, specify a system root that begins
2346 with the `remote:' prefix, either via the `set sysroot' command or via
2347 the `--with-sysroot' configure-time option.
2349 * "info sharedlibrary" now takes an optional regex of libraries to show,
2350 and it now reports if a shared library has no debugging information.
2352 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2353 now complete on file names.
2355 * When completing in expressions, gdb will attempt to limit
2356 completions to allowable structure or union fields, where appropriate.
2357 For instance, consider:
2359 # struct example { int f1; double f2; };
2360 # struct example variable;
2363 If the user types TAB at the end of this command line, the available
2364 completions will be "f1" and "f2".
2366 * Inlined functions are now supported. They show up in backtraces, and
2367 the "step", "next", and "finish" commands handle them automatically.
2369 * GDB now supports the token-splicing (##) and stringification (#)
2370 operators when expanding macros. It also supports variable-arity
2373 * GDB now supports inspecting extra signal information, exported by
2374 the new $_siginfo convenience variable. The feature is currently
2375 implemented on linux ARM, i386 and amd64.
2377 * GDB can now display the VFP floating point registers and NEON vector
2378 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2379 can provide these registers (requires Linux 2.6.30 or later). Remote
2380 and simulator targets may also provide them.
2382 * New remote packets
2385 Search memory for a sequence of bytes.
2388 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2389 operation over reliable transport links. Use of this packet is
2390 controlled by the `set remote noack-packet' command.
2393 Kill the process with the specified process ID. Use this in preference
2394 to `k' when multiprocess protocol extensions are supported.
2397 Obtains additional operating system information
2401 Read or write additional signal information.
2403 * Removed remote protocol undocumented extension
2405 An undocumented extension to the remote protocol's `S' stop reply
2406 packet that permited the stub to pass a process id was removed.
2407 Remote servers should use the `T' stop reply packet instead.
2409 * GDB now supports multiple function calling conventions according to the
2410 DWARF-2 DW_AT_calling_convention function attribute.
2412 * The SH target utilizes the aforementioned change to distinguish between gcc
2413 and Renesas calling convention. It also adds the new CLI commands
2414 `set/show sh calling-convention'.
2416 * GDB can now read compressed debug sections, as produced by GNU gold
2417 with the --compress-debug-sections=zlib flag.
2419 * 64-bit core files are now supported on AIX.
2421 * Thread switching is now supported on Tru64.
2423 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2424 which will be allocated using malloc later in program execution.
2426 * The qXfer:libraries:read remote procotol packet now allows passing a
2427 list of section offsets.
2429 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2430 conditions handling signals delivered during attach or thread creation
2431 have also been fixed.
2433 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2434 From the user's standpoint, all unqualified instances of True and False
2435 are treated as the standard definitions, regardless of context.
2437 * GDB now parses C++ symbol and type names more flexibly. For
2440 template<typename T> class C { };
2443 GDB will now correctly handle all of:
2445 ptype C<char const *>
2446 ptype C<char const*>
2447 ptype C<const char *>
2448 ptype C<const char*>
2450 * New features in the GDB remote stub, gdbserver
2452 - The "--wrapper" command-line argument tells gdbserver to use a
2453 wrapper program to launch programs for debugging.
2455 - On PowerPC and S/390 targets, it is now possible to use a single
2456 gdbserver executable to debug both 32-bit and 64-bit programs.
2457 (This requires gdbserver itself to be built as a 64-bit executable.)
2459 - gdbserver uses the new noack protocol mode for TCP connections to
2460 reduce communications latency, if also supported and enabled in GDB.
2462 - Support for the sparc64-linux-gnu target is now included in
2465 - The amd64-linux build of gdbserver now supports debugging both
2466 32-bit and 64-bit programs.
2468 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2469 now support hardware watchpoints, and will use them automatically
2474 GDB now has support for scripting using Python. Whether this is
2475 available is determined at configure time.
2477 New GDB commands can now be written in Python.
2479 * Ada tasking support
2481 Ada tasks can now be inspected in GDB. The following commands have
2485 Print the list of Ada tasks.
2487 Print detailed information about task number N.
2489 Print the task number of the current task.
2491 Switch the context of debugging to task number N.
2493 * Support for user-defined prefixed commands. The "define" command can
2494 add new commands to existing prefixes, e.g. "target".
2496 * Multi-inferior, multi-process debugging.
2498 GDB now has generalized support for multi-inferior debugging. See
2499 "Debugging Multiple Inferiors" in the manual for more information.
2500 Although availability still depends on target support, the command
2501 set is more uniform now. The GNU/Linux specific multi-forks support
2502 has been migrated to this new framework. This implied some user
2503 visible changes; see "New commands" and also "Removed commands"
2506 * Target descriptions can now describe the target OS ABI. See the
2507 "Target Description Format" section in the user manual for more
2510 * Target descriptions can now describe "compatible" architectures
2511 to indicate that the target can execute applications for a different
2512 architecture in addition to those for the main target architecture.
2513 See the "Target Description Format" section in the user manual for
2516 * Multi-architecture debugging.
2518 GDB now includes general supports for debugging applications on
2519 hybrid systems that use more than one single processor architecture
2520 at the same time. Each such hybrid architecture still requires
2521 specific support to be added. The only hybrid architecture supported
2522 in this version of GDB is the Cell Broadband Engine.
2524 * GDB now supports integrated debugging of Cell/B.E. applications that
2525 use both the PPU and SPU architectures. To enable support for hybrid
2526 Cell/B.E. debugging, you need to configure GDB to support both the
2527 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2528 --enable-targets configure option.
2530 * Non-stop mode debugging.
2532 For some targets, GDB now supports an optional mode of operation in
2533 which you can examine stopped threads while other threads continue
2534 to execute freely. This is referred to as non-stop mode, with the
2535 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2536 section in the user manual for more information.
2538 To be able to support remote non-stop debugging, a remote stub needs
2539 to implement the non-stop mode remote protocol extensions, as
2540 described in the "Remote Non-Stop" section of the user manual. The
2541 GDB remote stub, gdbserver, has been adjusted to support these
2542 extensions on linux targets.
2544 * New commands (for set/show, see "New options" below)
2546 catch syscall [NAME(S) | NUMBER(S)]
2547 Catch system calls. Arguments, which should be names of system
2548 calls or their numbers, mean catch only those syscalls. Without
2549 arguments, every syscall will be caught. When the inferior issues
2550 any of the specified syscalls, GDB will stop and announce the system
2551 call, both when it is called and when its call returns. This
2552 feature is currently available with a native GDB running on the
2553 Linux Kernel, under the following architectures: x86, x86_64,
2554 PowerPC and PowerPC64.
2556 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2558 Search memory for a sequence of bytes.
2560 maint set python print-stack
2561 maint show python print-stack
2562 Show a stack trace when an error is encountered in a Python script.
2565 Invoke CODE by passing it to the Python interpreter.
2570 These allow macros to be defined, undefined, and listed
2574 Show operating system information about processes.
2577 List the inferiors currently under GDB's control.
2580 Switch focus to inferior number NUM.
2583 Detach from inferior number NUM.
2586 Kill inferior number NUM.
2590 set spu stop-on-load
2591 show spu stop-on-load
2592 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2594 set spu auto-flush-cache
2595 show spu auto-flush-cache
2596 Control whether to automatically flush the software-managed cache
2597 during Cell/B.E. debugging.
2599 set sh calling-convention
2600 show sh calling-convention
2601 Control the calling convention used when calling SH target functions.
2604 show debug timestamp
2605 Control display of timestamps with GDB debugging output.
2607 set disassemble-next-line
2608 show disassemble-next-line
2609 Control display of disassembled source lines or instructions when
2612 set remote noack-packet
2613 show remote noack-packet
2614 Set/show the use of remote protocol QStartNoAckMode packet. See above
2615 under "New remote packets."
2617 set remote query-attached-packet
2618 show remote query-attached-packet
2619 Control use of remote protocol `qAttached' (query-attached) packet.
2621 set remote read-siginfo-object
2622 show remote read-siginfo-object
2623 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2626 set remote write-siginfo-object
2627 show remote write-siginfo-object
2628 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2631 set remote reverse-continue
2632 show remote reverse-continue
2633 Control use of remote protocol 'bc' (reverse-continue) packet.
2635 set remote reverse-step
2636 show remote reverse-step
2637 Control use of remote protocol 'bs' (reverse-step) packet.
2639 set displaced-stepping
2640 show displaced-stepping
2641 Control displaced stepping mode. Displaced stepping is a way to
2642 single-step over breakpoints without removing them from the debuggee.
2643 Also known as "out-of-line single-stepping".
2646 show debug displaced
2647 Control display of debugging info for displaced stepping.
2649 maint set internal-error
2650 maint show internal-error
2651 Control what GDB does when an internal error is detected.
2653 maint set internal-warning
2654 maint show internal-warning
2655 Control what GDB does when an internal warning is detected.
2660 Use a wrapper program to launch programs for debugging.
2662 set multiple-symbols (all|ask|cancel)
2663 show multiple-symbols
2664 The value of this variable can be changed to adjust the debugger behavior
2665 when an expression or a breakpoint location contains an ambiguous symbol
2666 name (an overloaded function name, for instance).
2668 set breakpoint always-inserted
2669 show breakpoint always-inserted
2670 Keep breakpoints always inserted in the target, as opposed to inserting
2671 them when resuming the target, and removing them when the target stops.
2672 This option can improve debugger performance on slow remote targets.
2674 set arm fallback-mode (arm|thumb|auto)
2675 show arm fallback-mode
2676 set arm force-mode (arm|thumb|auto)
2678 These commands control how ARM GDB determines whether instructions
2679 are ARM or Thumb. The default for both settings is auto, which uses
2680 the current CPSR value for instructions without symbols; previous
2681 versions of GDB behaved as if "set arm fallback-mode arm".
2683 set disable-randomization
2684 show disable-randomization
2685 Standalone programs run with the virtual address space randomization enabled
2686 by default on some platforms. This option keeps the addresses stable across
2687 multiple debugging sessions.
2691 Control whether other threads are stopped or not when some thread hits
2696 Requests that asynchronous execution is enabled in the target, if available.
2697 In this case, it's possible to resume target in the background, and interact
2698 with GDB while the target is running. "show target-async" displays the
2699 current state of asynchronous execution of the target.
2701 set target-wide-charset
2702 show target-wide-charset
2703 The target-wide-charset is the name of the character set that GDB
2704 uses when printing characters whose type is wchar_t.
2706 set tcp auto-retry (on|off)
2708 set tcp connect-timeout
2709 show tcp connect-timeout
2710 These commands allow GDB to retry failed TCP connections to a remote stub
2711 with a specified timeout period; this is useful if the stub is launched
2712 in parallel with GDB but may not be ready to accept connections immediately.
2714 set libthread-db-search-path
2715 show libthread-db-search-path
2716 Control list of directories which GDB will search for appropriate
2719 set schedule-multiple (on|off)
2720 show schedule-multiple
2721 Allow GDB to resume all threads of all processes or only threads of
2722 the current process.
2726 Use more aggressive caching for accesses to the stack. This improves
2727 performance of remote debugging (particularly backtraces) without
2728 affecting correctness.
2730 set interactive-mode (on|off|auto)
2731 show interactive-mode
2732 Control whether GDB runs in interactive mode (on) or not (off).
2733 When in interactive mode, GDB waits for the user to answer all
2734 queries. Otherwise, GDB does not wait and assumes the default
2735 answer. When set to auto (the default), GDB determines which
2736 mode to use based on the stdin settings.
2741 For program forks, this is replaced by the new more generic `info
2742 inferiors' command. To list checkpoints, you can still use the
2743 `info checkpoints' command, which was an alias for the `info forks'
2747 Replaced by the new `inferior' command. To switch between
2748 checkpoints, you can still use the `restart' command, which was an
2749 alias for the `fork' command.
2752 This is removed, since some targets don't have a notion of
2753 processes. To switch between processes, you can still use the
2754 `inferior' command using GDB's own inferior number.
2757 For program forks, this is replaced by the new more generic `kill
2758 inferior' command. To delete a checkpoint, you can still use the
2759 `delete checkpoint' command, which was an alias for the `delete
2763 For program forks, this is replaced by the new more generic `detach
2764 inferior' command. To detach a checkpoint, you can still use the
2765 `detach checkpoint' command, which was an alias for the `detach
2768 * New native configurations
2770 x86/x86_64 Darwin i[34567]86-*-darwin*
2772 x86_64 MinGW x86_64-*-mingw*
2776 Lattice Mico32 lm32-*
2777 x86 DICOS i[34567]86-*-dicos*
2778 x86_64 DICOS x86_64-*-dicos*
2781 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2782 (mingw32ce) debugging.
2788 These commands were actually not implemented on any target.
2790 *** Changes in GDB 6.8
2792 * New native configurations
2794 NetBSD/hppa hppa*-*netbsd*
2795 Xtensa GNU/Linux xtensa*-*-linux*
2799 NetBSD/hppa hppa*-*-netbsd*
2800 Xtensa GNU/Lunux xtensa*-*-linux*
2802 * Change in command line behavior -- corefiles vs. process ids.
2804 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2805 attaching to process NUMBER fails, GDB no longer attempts to open a
2806 core file named NUMBER. Attaching to a program using the -c option
2807 is no longer supported. Instead, use the '-p' or '--pid' options.
2809 * GDB can now be built as a native debugger for debugging Windows x86
2810 (mingw32) Portable Executable (PE) programs.
2812 * Pending breakpoints no longer change their number when their address
2815 * GDB now supports breakpoints with multiple locations,
2816 including breakpoints on C++ constructors, inside C++ templates,
2817 and in inlined functions.
2819 * GDB's ability to debug optimized code has been improved. GDB more
2820 accurately identifies function bodies and lexical blocks that occupy
2821 more than one contiguous range of addresses.
2823 * Target descriptions can now describe registers for PowerPC.
2825 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2826 registers on PowerPC targets.
2828 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2829 targets even when the libthread_db library is not available.
2831 * The GDB remote stub, gdbserver, now supports the new file transfer
2832 commands (remote put, remote get, and remote delete).
2834 * The GDB remote stub, gdbserver, now supports run and attach in
2835 extended-remote mode.
2837 * hppa*64*-*-hpux11* target broken
2838 The debugger is unable to start a program and fails with the following
2839 error: "Error trying to get information about dynamic linker".
2840 The gdb-6.7 release is also affected.
2842 * GDB now supports the --enable-targets= configure option to allow
2843 building a single GDB executable that supports multiple remote
2844 target architectures.
2846 * GDB now supports debugging C and C++ programs which use the
2847 Decimal Floating Point extension. In addition, the PowerPC target
2848 now has a set of pseudo-registers to inspect decimal float values
2849 stored in two consecutive float registers.
2851 * The -break-insert MI command can optionally create pending
2854 * Improved support for debugging Ada
2855 Many improvements to the Ada language support have been made. These
2857 - Better support for Ada2005 interface types
2858 - Improved handling of arrays and slices in general
2859 - Better support for Taft-amendment types
2860 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2862 - Improved command completion in Ada
2865 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2870 set print frame-arguments (all|scalars|none)
2871 show print frame-arguments
2872 The value of this variable can be changed to control which argument
2873 values should be printed by the debugger when displaying a frame.
2878 Transfer files to and from a remote target, and delete remote files.
2885 Transfer files to and from a remote target, and delete remote files.
2887 * New remote packets
2894 Open, close, read, write, and delete files on the remote system.
2897 Attach to an existing process on the remote system, in extended-remote
2901 Run a new process on the remote system, in extended-remote mode.
2903 *** Changes in GDB 6.7
2905 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2906 bfd, libiberty and opcodes, as revealed by static analysis donated by
2907 Coverity, Inc. (http://scan.coverity.com).
2909 * When looking up multiply-defined global symbols, GDB will now prefer the
2910 symbol definition in the current shared library if it was built using the
2911 -Bsymbolic linker option.
2913 * When the Text User Interface (TUI) is not configured, GDB will now
2914 recognize the -tui command-line option and print a message that the TUI
2917 * The GDB remote stub, gdbserver, now has lower overhead for high
2918 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2920 * GDB for MIPS targets now autodetects whether a remote target provides
2921 32-bit or 64-bit register values.
2923 * Support for C++ member pointers has been improved.
2925 * GDB now understands XML target descriptions, which specify the
2926 target's overall architecture. GDB can read a description from
2927 a local file or over the remote serial protocol.
2929 * Vectors of single-byte data use a new integer type which is not
2930 automatically displayed as character or string data.
2932 * The /s format now works with the print command. It displays
2933 arrays of single-byte integers and pointers to single-byte integers
2936 * Target descriptions can now describe target-specific registers,
2937 for architectures which have implemented the support (currently
2938 only ARM, M68K, and MIPS).
2940 * GDB and the GDB remote stub, gdbserver, now support the XScale
2943 * The GDB remote stub, gdbserver, has been updated to support
2944 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2945 has been rewritten to use the standard GDB remote protocol.
2947 * GDB can now step into C++ functions which are called through thunks.
2949 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2951 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2952 layout. It also supports a TextSeg= and DataSeg= response when only
2953 segment base addresses (rather than offsets) are available.
2955 * The /i format now outputs any trailing branch delay slot instructions
2956 immediately following the last instruction within the count specified.
2958 * The GDB remote protocol "T" stop reply packet now supports a
2959 "library" response. Combined with the new "qXfer:libraries:read"
2960 packet, this response allows GDB to debug shared libraries on targets
2961 where the operating system manages the list of loaded libraries (e.g.
2962 Windows and SymbianOS).
2964 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2965 (DLLs) on Windows and Windows CE targets.
2967 * GDB now supports a faster verification that a .debug file matches its binary
2968 according to its build-id signature, if the signature is present.
2974 Enable or disable hardware flow control (RTS/CTS) on the serial port
2975 when debugging using remote targets.
2977 set mem inaccessible-by-default
2978 show mem inaccessible-by-default
2979 If the target supplies a memory map, for instance via the remote
2980 protocol's "qXfer:memory-map:read" packet, setting this variable
2981 prevents GDB from accessing memory outside the memory map. This
2982 is useful for targets with memory mapped registers or which react
2983 badly to accesses of unmapped address space.
2985 set breakpoint auto-hw
2986 show breakpoint auto-hw
2987 If the target supplies a memory map, for instance via the remote
2988 protocol's "qXfer:memory-map:read" packet, setting this variable
2989 lets GDB use hardware breakpoints automatically for memory regions
2990 where it can not use software breakpoints. This covers both the
2991 "break" command and internal breakpoints used for other commands
2992 including "next" and "finish".
2995 catch exception unhandled
2996 Stop the program execution when Ada exceptions are raised.
2999 Stop the program execution when an Ada assertion failed.
3003 Set an alternate system root for target files. This is a more
3004 general version of "set solib-absolute-prefix", which is now
3005 an alias to "set sysroot".
3008 Provide extended SPU facility status information. This set of
3009 commands is available only when debugging the Cell/B.E. SPU
3012 * New native configurations
3014 OpenBSD/sh sh*-*openbsd*
3017 unset tdesc filename
3019 Use the specified local file as an XML target description, and do
3020 not query the target for its built-in description.
3024 OpenBSD/sh sh*-*-openbsd*
3025 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3026 Toshiba Media Processor mep-elf
3028 * New remote packets
3031 Ignore the specified signals; pass them directly to the debugged program
3032 without stopping other threads or reporting them to GDB.
3034 qXfer:features:read:
3035 Read an XML target description from the target, which describes its
3040 Read or write contents of an spufs file on the target system. These
3041 packets are available only on the Cell/B.E. SPU architecture.
3043 qXfer:libraries:read:
3044 Report the loaded shared libraries. Combined with new "T" packet
3045 response, this packet allows GDB to debug shared libraries on
3046 targets where the operating system manages the list of loaded
3047 libraries (e.g. Windows and SymbianOS).
3051 Support for these obsolete configurations has been removed.
3059 i[34567]86-*-lynxos*
3060 i[34567]86-*-netware*
3061 i[34567]86-*-sco3.2v5*
3062 i[34567]86-*-sco3.2v4*
3064 i[34567]86-*-sysv4.2*
3067 i[34567]86-*-unixware2*
3068 i[34567]86-*-unixware*
3077 * Other removed features
3084 Various m68k-only ROM monitors.
3091 Various Renesas ROM monitors and debugging interfaces for SH and
3096 Support for a Macraigor serial interface to on-chip debugging.
3097 GDB does not directly support the newer parallel or USB
3102 A debug information format. The predecessor to DWARF 2 and
3103 DWARF 3, which are still supported.
3105 Support for the HP aCC compiler on HP-UX/PA-RISC
3107 SOM-encapsulated symbolic debugging information, automatic
3108 invocation of pxdb, and the aCC custom C++ ABI. This does not
3109 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3110 with aCC can still be debugged on an assembly level.
3112 MIPS ".pdr" sections
3114 A MIPS-specific format used to describe stack frame layout
3115 in debugging information.
3119 GDB could work with an older version of Guile to debug
3120 the interpreter and Scheme programs running in it.
3122 set mips stack-arg-size
3123 set mips saved-gpreg-size
3125 Use "set mips abi" to control parameter passing for MIPS.
3127 *** Changes in GDB 6.6
3132 Cell Broadband Engine SPU spu-elf
3134 * GDB can now be configured as a cross-debugger targeting native Windows
3135 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3136 running on a Windows system over TCP/IP to debug Windows programs.
3138 * The GDB remote stub, gdbserver, has been updated to support Windows and
3139 Cygwin debugging. Both single-threaded and multi-threaded programs are
3142 * The "set trust-readonly-sections" command works again. This command was
3143 broken in GDB 6.3, 6.4, and 6.5.
3145 * The "load" command now supports writing to flash memory, if the remote
3146 stub provides the required support.
3148 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3149 longer requires symbolic debug information (e.g. DWARF-2).
3154 unset substitute-path
3155 show substitute-path
3156 Manage a list of substitution rules that GDB uses to rewrite the name
3157 of the directories where the sources are located. This can be useful
3158 for instance when the sources were moved to a different location
3159 between compilation and debugging.
3163 Print each CLI command as it is executed. Each command is prefixed with
3164 a number of `+' symbols representing the nesting depth.
3165 The source command now has a `-v' option to enable the same feature.
3169 The ARM Demon monitor support (RDP protocol, "target rdp").
3171 Kernel Object Display, an embedded debugging feature which only worked with
3172 an obsolete version of Cisco IOS.
3174 The 'set download-write-size' and 'show download-write-size' commands.
3176 * New remote packets
3179 Tell a stub about GDB client features, and request remote target features.
3180 The first feature implemented is PacketSize, which allows the target to
3181 specify the size of packets it can handle - to minimize the number of
3182 packets required and improve performance when connected to a remote
3186 Fetch an OS auxilliary vector from the remote stub. This packet is a
3187 more efficient replacement for qPart:auxv:read.
3189 qXfer:memory-map:read:
3190 Fetch a memory map from the remote stub, including information about
3191 RAM, ROM, and flash memory devices.
3196 Erase and program a flash memory device.
3198 * Removed remote packets
3201 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3202 used it, and only gdbserver implemented it.
3204 *** Changes in GDB 6.5
3208 Renesas M32C/M16C m32c-elf
3210 Morpho Technologies ms1 ms1-elf
3214 init-if-undefined Initialize a convenience variable, but
3215 only if it doesn't already have a value.
3217 The following commands are presently only implemented for native GNU/Linux:
3219 checkpoint Save a snapshot of the program state.
3221 restart <n> Return the program state to a
3222 previously saved state.
3224 info checkpoints List currently saved checkpoints.
3226 delete-checkpoint <n> Delete a previously saved checkpoint.
3228 set|show detach-on-fork Tell gdb whether to detach from a newly
3229 forked process, or to keep debugging it.
3231 info forks List forks of the user program that
3232 are available to be debugged.
3234 fork <n> Switch to debugging one of several
3235 forks of the user program that are
3236 available to be debugged.
3238 delete-fork <n> Delete a fork from the list of forks
3239 that are available to be debugged (and
3240 kill the forked process).
3242 detach-fork <n> Delete a fork from the list of forks
3243 that are available to be debugged (and
3244 allow the process to continue).
3248 Morpho Technologies ms2 ms1-elf
3250 * Improved Windows host support
3252 GDB now builds as a cross debugger hosted on i686-mingw32, including
3253 native console support, and remote communications using either
3254 network sockets or serial ports.
3256 * Improved Modula-2 language support
3258 GDB can now print most types in the Modula-2 syntax. This includes:
3259 basic types, set types, record types, enumerated types, range types,
3260 pointer types and ARRAY types. Procedure var parameters are correctly
3261 printed and hexadecimal addresses and character constants are also
3262 written in the Modula-2 syntax. Best results can be obtained by using
3263 GNU Modula-2 together with the -gdwarf-2 command line option.
3267 The ARM rdi-share module.
3269 The Netware NLM debug server.
3271 *** Changes in GDB 6.4
3273 * New native configurations
3275 OpenBSD/arm arm*-*-openbsd*
3276 OpenBSD/mips64 mips64-*-openbsd*
3280 Morpho Technologies ms1 ms1-elf
3282 * New command line options
3284 --batch-silent As for --batch, but totally silent.
3285 --return-child-result The debugger will exist with the same value
3286 the child (debugged) program exited with.
3287 --eval-command COMMAND, -ex COMMAND
3288 Execute a single GDB CLI command. This may be
3289 specified multiple times and in conjunction
3290 with the --command (-x) option.
3292 * Deprecated commands removed
3294 The following commands, that were deprecated in 2000, have been
3298 set|show arm disassembly-flavor set|show arm disassembler
3299 othernames set arm disassembler
3300 set|show remotedebug set|show debug remote
3301 set|show archdebug set|show debug arch
3302 set|show eventdebug set|show debug event
3305 * New BSD user-level threads support
3307 It is now possible to debug programs using the user-level threads
3308 library on OpenBSD and FreeBSD. Currently supported (target)
3311 FreeBSD/amd64 x86_64-*-freebsd*
3312 FreeBSD/i386 i386-*-freebsd*
3313 OpenBSD/i386 i386-*-openbsd*
3315 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3316 are not yet supported.
3318 * New support for Matsushita MN10300 w/sim added
3319 (Work in progress). mn10300-elf.
3321 * REMOVED configurations and files
3323 VxWorks and the XDR protocol *-*-vxworks
3324 Motorola MCORE mcore-*-*
3325 National Semiconductor NS32000 ns32k-*-*
3327 * New "set print array-indexes" command
3329 After turning this setting "on", GDB prints the index of each element
3330 when displaying arrays. The default is "off" to preserve the previous
3333 * VAX floating point support
3335 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3337 * User-defined command support
3339 In addition to using $arg0..$arg9 for argument passing, it is now possible
3340 to use $argc to determine now many arguments have been passed. See the
3341 section on user-defined commands in the user manual for more information.
3343 *** Changes in GDB 6.3:
3345 * New command line option
3347 GDB now accepts -l followed by a number to set the timeout for remote
3350 * GDB works with GCC -feliminate-dwarf2-dups
3352 GDB now supports a more compact representation of DWARF-2 debug
3353 information using DW_FORM_ref_addr references. These are produced
3354 by GCC with the option -feliminate-dwarf2-dups and also by some
3355 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3356 to use -feliminate-dwarf2-dups.
3358 * Internationalization
3360 When supported by the host system, GDB will be built with
3361 internationalization (libintl). The task of marking up the sources is
3362 continued, we're looking forward to our first translation.
3366 Initial support for debugging programs compiled with the GNAT
3367 implementation of the Ada programming language has been integrated
3368 into GDB. In this release, support is limited to expression evaluation.
3370 * New native configurations
3372 GNU/Linux/m32r m32r-*-linux-gnu
3376 GDB's remote protocol now includes support for the 'p' packet. This
3377 packet is used to fetch individual registers from a remote inferior.
3379 * END-OF-LIFE registers[] compatibility module
3381 GDB's internal register infrastructure has been completely rewritten.
3382 The new infrastructure making possible the implementation of key new
3383 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3386 GDB 6.3 will be the last release to include the the registers[]
3387 compatibility module that allowed out-of-date configurations to
3388 continue to work. This change directly impacts the following
3398 powerpc bdm protocol
3400 Unless there is activity to revive these configurations, they will be
3401 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3403 * OBSOLETE configurations and files
3405 Configurations that have been declared obsolete in this release have
3406 been commented out. Unless there is activity to revive these
3407 configurations, the next release of GDB will have their sources
3408 permanently REMOVED.
3417 *** Changes in GDB 6.2.1:
3419 * MIPS `break main; run' gave an heuristic-fence-post warning
3421 When attempting to run even a simple program, a warning about
3422 heuristic-fence-post being hit would be reported. This problem has
3425 * MIPS IRIX 'long double' crashed GDB
3427 When examining a long double variable, GDB would get a segmentation
3428 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3429 IRIX long double values).
3433 A bug in the VAX stack code was causing problems with the "next"
3434 command. This problem has been fixed.
3436 *** Changes in GDB 6.2:
3438 * Fix for ``many threads''
3440 On GNU/Linux systems that use the NPTL threads library, a program
3441 rapidly creating and deleting threads would confuse GDB leading to the
3444 ptrace: No such process.
3445 thread_db_get_info: cannot get thread info: generic error
3447 This problem has been fixed.
3449 * "-async" and "-noasync" options removed.
3451 Support for the broken "-noasync" option has been removed (it caused
3454 * New ``start'' command.
3456 This command runs the program until the begining of the main procedure.
3458 * New BSD Kernel Data Access Library (libkvm) interface
3460 Using ``target kvm'' it is now possible to debug kernel core dumps and
3461 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3462 platforms. Currently supported (native-only) configurations are:
3464 FreeBSD/amd64 x86_64-*-freebsd*
3465 FreeBSD/i386 i?86-*-freebsd*
3466 NetBSD/i386 i?86-*-netbsd*
3467 NetBSD/m68k m68*-*-netbsd*
3468 NetBSD/sparc sparc-*-netbsd*
3469 OpenBSD/amd64 x86_64-*-openbsd*
3470 OpenBSD/i386 i?86-*-openbsd*
3471 OpenBSD/m68k m68*-openbsd*
3472 OpenBSD/sparc sparc-*-openbsd*
3474 * Signal trampoline code overhauled
3476 Many generic problems with GDB's signal handling code have been fixed.
3477 These include: backtraces through non-contiguous stacks; recognition
3478 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3479 call; backtrace through a signal trampoline; step into and out of
3480 signal handlers; and single-stepping in the signal trampoline.
3482 Please note that kernel bugs are a limiting factor here. These
3483 features have been shown to work on an s390 GNU/Linux system that
3484 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3486 * Cygwin support for DWARF 2 added.
3488 * New native configurations
3490 GNU/Linux/hppa hppa*-*-linux*
3491 OpenBSD/hppa hppa*-*-openbsd*
3492 OpenBSD/m68k m68*-*-openbsd*
3493 OpenBSD/m88k m88*-*-openbsd*
3494 OpenBSD/powerpc powerpc-*-openbsd*
3495 NetBSD/vax vax-*-netbsd*
3496 OpenBSD/vax vax-*-openbsd*
3498 * END-OF-LIFE frame compatibility module
3500 GDB's internal frame infrastructure has been completely rewritten.
3501 The new infrastructure making it possible to support key new features
3502 including DWARF 2 Call Frame Information. To aid in the task of
3503 migrating old configurations to this new infrastructure, a
3504 compatibility module, that allowed old configurations to continue to
3505 work, was also included.
3507 GDB 6.2 will be the last release to include this frame compatibility
3508 module. This change directly impacts the following configurations:
3518 Unless there is activity to revive these configurations, they will be
3519 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3521 * REMOVED configurations and files
3523 Sun 3, running SunOS 3 m68*-*-sunos3*
3524 Sun 3, running SunOS 4 m68*-*-sunos4*
3525 Sun 2, running SunOS 3 m68000-*-sunos3*
3526 Sun 2, running SunOS 4 m68000-*-sunos4*
3527 Motorola 680x0 running LynxOS m68*-*-lynxos*
3528 AT&T 3b1/Unix pc m68*-att-*
3529 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3530 decstation mips-dec-* mips-little-*
3531 riscos mips-*-riscos* mips-*-sysv*
3532 sonymips mips-sony-*
3533 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3535 *** Changes in GDB 6.1.1:
3537 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3539 The TUI (Text-mode User Interface) is now built as part of a default
3540 GDB configuration. It is enabled by either selecting the TUI with the
3541 command line option "-i=tui" or by running the separate "gdbtui"
3542 program. For more information on the TUI, see the manual "Debugging
3545 * Pending breakpoint support (also included in GDB 6.1)
3547 Support has been added to allow you to specify breakpoints in shared
3548 libraries that have not yet been loaded. If a breakpoint location
3549 cannot be found, and the "breakpoint pending" option is set to auto,
3550 GDB queries you if you wish to make the breakpoint pending on a future
3551 shared-library load. If and when GDB resolves the breakpoint symbol,
3552 the pending breakpoint is removed as one or more regular breakpoints
3555 Pending breakpoints are very useful for GCJ Java debugging.
3557 * Fixed ISO-C build problems
3559 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3560 non ISO-C code that stopped them being built using a more strict ISO-C
3561 compiler (e.g., IBM's C compiler).
3563 * Fixed build problem on IRIX 5
3565 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3566 wasn't able to compile compile on an IRIX 5 system.
3568 * Added execute permission to gdb/gdbserver/configure
3570 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3571 permission. This bug would cause configure to fail on a number of
3572 systems (Solaris, IRIX). Ref: server/519.
3574 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3576 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3577 has been updated to use constant array sizes.
3579 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3581 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3582 its generated DWARF Call Frame Info. This encoding was causing GDB to
3583 panic, that panic has been fixed. Ref: gdb/1628.
3585 * Fixed a problem when examining parameters in shared library code.
3587 When examining parameters in optimized shared library code generated
3588 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3589 not available''. GDB now correctly displays the variable's value.
3591 *** Changes in GDB 6.1:
3593 * Removed --with-mmalloc
3595 Support for the mmalloc memory manager has been removed, as it
3596 conflicted with the internal gdb byte cache.
3598 * Changes in AMD64 configurations
3600 The AMD64 target now includes the %cs and %ss registers. As a result
3601 the AMD64 remote protocol has changed; this affects the floating-point
3602 and SSE registers. If you rely on those registers for your debugging,
3603 you should upgrade gdbserver on the remote side.
3605 * Revised SPARC target
3607 The SPARC target has been completely revised, incorporating the
3608 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3609 support for LynxOS and SunOS 4 has been dropped. Calling functions
3610 from within GDB on operating systems with a non-executable stack
3611 (Solaris, OpenBSD) now works.
3615 GDB has a new C++ demangler which does a better job on the mangled
3616 names generated by current versions of g++. It also runs faster, so
3617 with this and other changes gdb should now start faster on large C++
3620 * DWARF 2 Location Expressions
3622 GDB support for location expressions has been extended to support function
3623 arguments and frame bases. Older versions of GDB could crash when they
3626 * C++ nested types and namespaces
3628 GDB's support for nested types and namespaces in C++ has been
3629 improved, especially if you use the DWARF 2 debugging format. (This
3630 is the default for recent versions of GCC on most platforms.)
3631 Specifically, if you have a class "Inner" defined within a class or
3632 namespace "Outer", then GDB realizes that the class's name is
3633 "Outer::Inner", not simply "Inner". This should greatly reduce the
3634 frequency of complaints about not finding RTTI symbols. In addition,
3635 if you are stopped at inside of a function defined within a namespace,
3636 GDB modifies its name lookup accordingly.
3638 * New native configurations
3640 NetBSD/amd64 x86_64-*-netbsd*
3641 OpenBSD/amd64 x86_64-*-openbsd*
3642 OpenBSD/alpha alpha*-*-openbsd*
3643 OpenBSD/sparc sparc-*-openbsd*
3644 OpenBSD/sparc64 sparc64-*-openbsd*
3646 * New debugging protocols
3648 M32R with SDI protocol m32r-*-elf*
3650 * "set prompt-escape-char" command deleted.
3652 The command "set prompt-escape-char" has been deleted. This command,
3653 and its very obscure effet on GDB's prompt, was never documented,
3654 tested, nor mentioned in the NEWS file.
3656 * OBSOLETE configurations and files
3658 Configurations that have been declared obsolete in this release have
3659 been commented out. Unless there is activity to revive these
3660 configurations, the next release of GDB will have their sources
3661 permanently REMOVED.
3663 Sun 3, running SunOS 3 m68*-*-sunos3*
3664 Sun 3, running SunOS 4 m68*-*-sunos4*
3665 Sun 2, running SunOS 3 m68000-*-sunos3*
3666 Sun 2, running SunOS 4 m68000-*-sunos4*
3667 Motorola 680x0 running LynxOS m68*-*-lynxos*
3668 AT&T 3b1/Unix pc m68*-att-*
3669 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3670 decstation mips-dec-* mips-little-*
3671 riscos mips-*-riscos* mips-*-sysv*
3672 sonymips mips-sony-*
3673 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3675 * REMOVED configurations and files
3677 SGI Irix-4.x mips-sgi-irix4 or iris4
3678 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3679 Z8000 simulator z8k-zilog-none or z8ksim
3680 Matsushita MN10200 w/simulator mn10200-*-*
3681 H8/500 simulator h8500-hitachi-hms or h8500hms
3682 HP/PA running BSD hppa*-*-bsd*
3683 HP/PA running OSF/1 hppa*-*-osf*
3684 HP/PA Pro target hppa*-*-pro*
3685 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3686 386BSD i[3456]86-*-bsd*
3687 Sequent family i[3456]86-sequent-sysv4*
3688 i[3456]86-sequent-sysv*
3689 i[3456]86-sequent-bsd*
3690 SPARC running LynxOS sparc-*-lynxos*
3691 SPARC running SunOS 4 sparc-*-sunos4*
3692 Tsqware Sparclet sparclet-*-*
3693 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3695 *** Changes in GDB 6.0:
3699 Support for debugging the Objective-C programming language has been
3700 integrated into GDB.
3702 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3704 DWARF 2's Call Frame Information makes available compiler generated
3705 information that more exactly describes the program's run-time stack.
3706 By using this information, GDB is able to provide more robust stack
3709 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3710 have been updated to use a new backtrace mechanism which includes
3711 DWARF 2 CFI support.
3715 GDB's remote protocol has been extended to include support for hosted
3716 file I/O (where the remote target uses GDB's file system). See GDB's
3717 remote protocol documentation for details.
3719 * All targets using the new architecture framework.
3721 All of GDB's targets have been updated to use the new internal
3722 architecture framework. The way is now open for future GDB releases
3723 to include cross-architecture native debugging support (i386 on amd64,
3726 * GNU/Linux's Thread Local Storage (TLS)
3728 GDB now includes support for for the GNU/Linux implementation of
3729 per-thread variables.
3731 * GNU/Linux's Native POSIX Thread Library (NPTL)
3733 GDB's thread code has been updated to work with either the new
3734 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3736 * Separate debug info.
3738 GDB, in conjunction with BINUTILS, now supports a mechanism for
3739 automatically loading debug information from a separate file. Instead
3740 of shipping full debug and non-debug versions of system libraries,
3741 system integrators can now instead ship just the stripped libraries
3742 and optional debug files.
3744 * DWARF 2 Location Expressions
3746 DWARF 2 Location Expressions allow the compiler to more completely
3747 describe the location of variables (even in optimized code) to the
3750 GDB now includes preliminary support for location expressions (support
3751 for DW_OP_piece is still missing).
3755 A number of long standing bugs that caused GDB to die while starting a
3756 Java application have been fixed. GDB's Java support is now
3757 considered "useable".
3759 * GNU/Linux support for fork, vfork, and exec.
3761 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3762 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3765 * GDB supports logging output to a file
3767 There are two new commands, "set logging" and "show logging", which can be
3768 used to capture GDB's output to a file.
3770 * The meaning of "detach" has changed for gdbserver
3772 The "detach" command will now resume the application, as documented. To
3773 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3776 * d10v, m68hc11 `regs' command deprecated
3778 The `info registers' command has been updated so that it displays the
3779 registers using a format identical to the old `regs' command.
3783 A new command, "maint set profile on/off", has been added. This command can
3784 be used to enable or disable profiling while running GDB, to profile a
3785 session or a set of commands. In addition there is a new configure switch,
3786 "--enable-profiling", which will cause GDB to be compiled with profiling
3787 data, for more informative profiling results.
3789 * Default MI syntax changed to "mi2".
3791 The default MI (machine interface) syntax, enabled by the command line
3792 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3793 "mi1", can be enabled by specifying the option "-i=mi1".
3795 Support for the original "mi0" syntax (included in GDB 5.0) has been
3798 Fix for gdb/192: removed extraneous space when displaying frame level.
3799 Fix for gdb/672: update changelist is now output in mi list format.
3800 Fix for gdb/702: a -var-assign that updates the value now shows up
3801 in a subsequent -var-update.
3803 * New native configurations.
3805 FreeBSD/amd64 x86_64-*-freebsd*
3807 * Multi-arched targets.
3809 HP/PA HPUX11 hppa*-*-hpux*
3810 Renesas M32R/D w/simulator m32r-*-elf*
3812 * OBSOLETE configurations and files
3814 Configurations that have been declared obsolete in this release have
3815 been commented out. Unless there is activity to revive these
3816 configurations, the next release of GDB will have their sources
3817 permanently REMOVED.
3819 Z8000 simulator z8k-zilog-none or z8ksim
3820 Matsushita MN10200 w/simulator mn10200-*-*
3821 H8/500 simulator h8500-hitachi-hms or h8500hms
3822 HP/PA running BSD hppa*-*-bsd*
3823 HP/PA running OSF/1 hppa*-*-osf*
3824 HP/PA Pro target hppa*-*-pro*
3825 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3826 Sequent family i[3456]86-sequent-sysv4*
3827 i[3456]86-sequent-sysv*
3828 i[3456]86-sequent-bsd*
3829 Tsqware Sparclet sparclet-*-*
3830 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3832 * REMOVED configurations and files
3835 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3836 IBM AIX PS/2 i[3456]86-*-aix
3837 i386 running Mach 3.0 i[3456]86-*-mach3*
3838 i386 running Mach i[3456]86-*-mach*
3839 i386 running OSF/1 i[3456]86-*osf1mk*
3840 HP/Apollo 68k Family m68*-apollo*-sysv*,
3842 m68*-hp-bsd*, m68*-hp-hpux*
3843 Argonaut Risc Chip (ARC) arc-*-*
3844 Mitsubishi D30V d30v-*-*
3845 Fujitsu FR30 fr30-*-elf*
3846 OS/9000 i[34]86-*-os9k
3847 I960 with MON960 i960-*-coff
3849 * MIPS $fp behavior changed
3851 The convenience variable $fp, for the MIPS, now consistently returns
3852 the address of the current frame's base. Previously, depending on the
3853 context, $fp could refer to either $sp or the current frame's base
3854 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3855 The GNU Source-Level Debugger''.
3857 *** Changes in GDB 5.3:
3859 * GNU/Linux shared library multi-threaded performance improved.
3861 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3862 `/proc', in preference to `ptrace' for memory reads. This may result
3863 in an improvement in the start-up time of multi-threaded, shared
3864 library applications when run under GDB. One GDB user writes: ``loads
3865 shared libs like mad''.
3867 * ``gdbserver'' now supports multi-threaded applications on some targets
3869 Support for debugging multi-threaded applications which use
3870 the GNU/Linux LinuxThreads package has been added for
3871 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3872 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3874 * GDB now supports C/C++ preprocessor macros.
3876 GDB now expands preprocessor macro invocations in C/C++ expressions,
3877 and provides various commands for showing macro definitions and how
3880 The new command `macro expand EXPRESSION' expands any macro
3881 invocations in expression, and shows the result.
3883 The new command `show macro MACRO-NAME' shows the definition of the
3884 macro named MACRO-NAME, and where it was defined.
3886 Most compilers don't include information about macros in the debugging
3887 information by default. In GCC 3.1, for example, you need to compile
3888 your program with the options `-gdwarf-2 -g3'. If the macro
3889 information is present in the executable, GDB will read it.
3891 * Multi-arched targets.
3893 DEC Alpha (partial) alpha*-*-*
3894 DEC VAX (partial) vax-*-*
3896 National Semiconductor NS32000 (partial) ns32k-*-*
3897 Motorola 68000 (partial) m68k-*-*
3898 Motorola MCORE mcore-*-*
3902 Fujitsu FRV architecture added by Red Hat frv*-*-*
3905 * New native configurations
3907 Alpha NetBSD alpha*-*-netbsd*
3908 SH NetBSD sh*-*-netbsdelf*
3909 MIPS NetBSD mips*-*-netbsd*
3910 UltraSPARC NetBSD sparc64-*-netbsd*
3912 * OBSOLETE configurations and files
3914 Configurations that have been declared obsolete in this release have
3915 been commented out. Unless there is activity to revive these
3916 configurations, the next release of GDB will have their sources
3917 permanently REMOVED.
3919 Mitsubishi D30V d30v-*-*
3920 OS/9000 i[34]86-*-os9k
3921 IBM AIX PS/2 i[3456]86-*-aix
3922 Fujitsu FR30 fr30-*-elf*
3923 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3924 Argonaut Risc Chip (ARC) arc-*-*
3925 i386 running Mach 3.0 i[3456]86-*-mach3*
3926 i386 running Mach i[3456]86-*-mach*
3927 i386 running OSF/1 i[3456]86-*osf1mk*
3928 HP/Apollo 68k Family m68*-apollo*-sysv*,
3930 m68*-hp-bsd*, m68*-hp-hpux*
3931 I960 with MON960 i960-*-coff
3933 * OBSOLETE languages
3935 CHILL, a Pascal like language used by telecommunications companies.
3937 * REMOVED configurations and files
3939 AMD 29k family via UDI a29k-amd-udi, udi29k
3940 A29K VxWorks a29k-*-vxworks
3941 AMD 29000 embedded, using EBMON a29k-none-none
3942 AMD 29000 embedded with COFF a29k-none-coff
3943 AMD 29000 embedded with a.out a29k-none-aout
3945 testsuite/gdb.hp/gdb.threads-hp/ directory
3947 * New command "set max-user-call-depth <nnn>"
3949 This command allows the user to limit the call depth of user-defined
3950 commands. The default is 1024.
3952 * Changes in FreeBSD/i386 native debugging.
3954 Support for the "generate-core-file" has been added.
3956 * New commands "dump", "append", and "restore".
3958 These commands allow data to be copied from target memory
3959 to a bfd-format or binary file (dump and append), and back
3960 from a file into memory (restore).
3962 * Improved "next/step" support on multi-processor Alpha Tru64.
3964 The previous single-step mechanism could cause unpredictable problems,
3965 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3966 of a software single-step mechanism prevents this.
3968 *** Changes in GDB 5.2.1:
3976 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3977 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3978 Fix, by Joel Brobecker imported from mainline.
3980 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3981 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3982 Fix, by Fred Fish, imported from mainline.
3984 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3985 Surprisingly enough, it works now.
3986 By Michal Ludvig, imported from mainline.
3988 i386 hardware watchpoint support:
3989 avoid misses on second run for some targets.
3990 By Pierre Muller, imported from mainline.
3992 *** Changes in GDB 5.2:
3994 * New command "set trust-readonly-sections on[off]".
3996 This command is a hint that tells gdb that read-only sections
3997 really are read-only (ie. that their contents will not change).
3998 In this mode, gdb will go to the object file rather than the
3999 target to read memory from read-only sections (such as ".text").
4000 This can be a significant performance improvement on some
4001 (notably embedded) targets.
4003 * New command "generate-core-file" (or "gcore").
4005 This new gdb command allows the user to drop a core file of the child
4006 process state at any time. So far it's been implemented only for
4007 GNU/Linux and Solaris, but should be relatively easily ported to other
4008 hosts. Argument is core file name (defaults to core.<pid>).
4010 * New command line option
4012 GDB now accepts --pid or -p followed by a process id.
4014 * Change in command line behavior -- corefiles vs. process ids.
4016 There is a subtle behavior in the way in which GDB handles
4017 command line arguments. The first non-flag argument is always
4018 a program to debug, but the second non-flag argument may either
4019 be a corefile or a process id. Previously, GDB would attempt to
4020 open the second argument as a corefile, and if that failed, would
4021 issue a superfluous error message and then attempt to attach it as
4022 a process. Now, if the second argument begins with a non-digit,
4023 it will be treated as a corefile. If it begins with a digit,
4024 GDB will attempt to attach it as a process, and if no such process
4025 is found, will then attempt to open it as a corefile.
4027 * Changes in ARM configurations.
4029 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4030 configuration is fully multi-arch.
4032 * New native configurations
4034 ARM NetBSD arm*-*-netbsd*
4035 x86 OpenBSD i[3456]86-*-openbsd*
4036 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4037 Sparc64 running FreeBSD sparc64-*-freebsd*
4041 Sanyo XStormy16 xstormy16-elf
4043 * OBSOLETE configurations and files
4045 Configurations that have been declared obsolete in this release have
4046 been commented out. Unless there is activity to revive these
4047 configurations, the next release of GDB will have their sources
4048 permanently REMOVED.
4050 AMD 29k family via UDI a29k-amd-udi, udi29k
4051 A29K VxWorks a29k-*-vxworks
4052 AMD 29000 embedded, using EBMON a29k-none-none
4053 AMD 29000 embedded with COFF a29k-none-coff
4054 AMD 29000 embedded with a.out a29k-none-aout
4056 testsuite/gdb.hp/gdb.threads-hp/ directory
4058 * REMOVED configurations and files
4060 TI TMS320C80 tic80-*-*
4062 PowerPC Solaris powerpcle-*-solaris*
4063 PowerPC Windows NT powerpcle-*-cygwin32
4064 PowerPC Netware powerpc-*-netware*
4065 Harris/CXUX m88k m88*-harris-cxux*
4066 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4067 ns32k-utek-sysv* ns32k-utek-*
4068 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4069 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4070 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4071 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4072 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4074 * Changes to command line processing
4076 The new `--args' feature can be used to specify command-line arguments
4077 for the inferior from gdb's command line.
4079 * Changes to key bindings
4081 There is a new `operate-and-get-next' function bound to `C-o'.
4083 *** Changes in GDB 5.1.1
4085 Fix compile problem on DJGPP.
4087 Fix a problem with floating-point registers on the i386 being
4090 Fix to stop GDB crashing on .debug_str debug info.
4092 Numerous documentation fixes.
4094 Numerous testsuite fixes.
4096 *** Changes in GDB 5.1:
4098 * New native configurations
4100 Alpha FreeBSD alpha*-*-freebsd*
4101 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4102 MIPS GNU/Linux mips*-*-linux*
4103 MIPS SGI Irix 6.x mips*-sgi-irix6*
4104 ia64 AIX ia64-*-aix*
4105 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4109 Motorola 68HC11 and 68HC12 m68hc11-elf
4111 UltraSparc running GNU/Linux sparc64-*-linux*
4113 * OBSOLETE configurations and files
4115 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4116 Harris/CXUX m88k m88*-harris-cxux*
4117 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4118 ns32k-utek-sysv* ns32k-utek-*
4119 TI TMS320C80 tic80-*-*
4121 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4122 PowerPC Solaris powerpcle-*-solaris*
4123 PowerPC Windows NT powerpcle-*-cygwin32
4124 PowerPC Netware powerpc-*-netware*
4125 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4126 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4127 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4128 Apple Macintosh (MPW) host N/A
4130 stuff.c (Program to stuff files into a specially prepared space in kdb)
4131 kdb-start.c (Main loop for the standalone kernel debugger)
4133 Configurations that have been declared obsolete in this release have
4134 been commented out. Unless there is activity to revive these
4135 configurations, the next release of GDB will have their sources
4136 permanently REMOVED.
4138 * REMOVED configurations and files
4140 Altos 3068 m68*-altos-*
4141 Convex c1-*-*, c2-*-*
4143 ARM RISCix arm-*-* (as host)
4147 * GDB has been converted to ISO C.
4149 GDB's source code has been converted to ISO C. In particular, the
4150 sources are fully protoized, and rely on standard headers being
4155 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4157 * The MI enabled by default.
4159 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4160 revised and enabled by default. Packages which use GDB as a debugging
4161 engine behind a UI or another front end are encouraged to switch to
4162 using the GDB/MI interface, instead of the old annotations interface
4163 which is now deprecated.
4165 * Support for debugging Pascal programs.
4167 GDB now includes support for debugging Pascal programs. The following
4168 main features are supported:
4170 - Pascal-specific data types such as sets;
4172 - automatic recognition of Pascal sources based on file-name
4175 - Pascal-style display of data types, variables, and functions;
4177 - a Pascal expression parser.
4179 However, some important features are not yet supported.
4181 - Pascal string operations are not supported at all;
4183 - there are some problems with boolean types;
4185 - Pascal type hexadecimal constants are not supported
4186 because they conflict with the internal variables format;
4188 - support for Pascal objects and classes is not full yet;
4190 - unlike Pascal, GDB is case-sensitive for symbol names.
4192 * Changes in completion.
4194 Commands such as `shell', `run' and `set args', which pass arguments
4195 to inferior programs, now complete on file names, similar to what
4196 users expect at the shell prompt.
4198 Commands which accept locations, such as `disassemble', `print',
4199 `breakpoint', `until', etc. now complete on filenames as well as
4200 program symbols. Thus, if you type "break foob TAB", and the source
4201 files linked into the programs include `foobar.c', that file name will
4202 be one of the candidates for completion. However, file names are not
4203 considered for completion after you typed a colon that delimits a file
4204 name from a name of a function in that file, as in "break foo.c:bar".
4206 `set demangle-style' completes on available demangling styles.
4208 * New platform-independent commands:
4210 It is now possible to define a post-hook for a command as well as a
4211 hook that runs before the command. For more details, see the
4212 documentation of `hookpost' in the GDB manual.
4214 * Changes in GNU/Linux native debugging.
4216 Support for debugging multi-threaded programs has been completely
4217 revised for all platforms except m68k and sparc. You can now debug as
4218 many threads as your system allows you to have.
4220 Attach/detach is supported for multi-threaded programs.
4222 Support for SSE registers was added for x86. This doesn't work for
4223 multi-threaded programs though.
4225 * Changes in MIPS configurations.
4227 Multi-arch support is enabled for all MIPS configurations.
4229 GDB can now be built as native debugger on SGI Irix 6.x systems for
4230 debugging n32 executables. (Debugging 64-bit executables is not yet
4233 * Unified support for hardware watchpoints in all x86 configurations.
4235 Most (if not all) native x86 configurations support hardware-assisted
4236 breakpoints and watchpoints in a unified manner. This support
4237 implements debug register sharing between watchpoints, which allows to
4238 put a virtually infinite number of watchpoints on the same address,
4239 and also supports watching regions up to 16 bytes with several debug
4242 The new maintenance command `maintenance show-debug-regs' toggles
4243 debugging print-outs in functions that insert, remove, and test
4244 watchpoints and hardware breakpoints.
4246 * Changes in the DJGPP native configuration.
4248 New command ``info dos sysinfo'' displays assorted information about
4249 the CPU, OS, memory, and DPMI server.
4251 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4252 display information about segment descriptors stored in GDT, LDT, and
4255 New commands ``info dos pde'' and ``info dos pte'' display entries
4256 from Page Directory and Page Tables (for now works with CWSDPMI only).
4257 New command ``info dos address-pte'' displays the Page Table entry for
4258 a given linear address.
4260 GDB can now pass command lines longer than 126 characters to the
4261 program being debugged (requires an update to the libdbg.a library
4262 which is part of the DJGPP development kit).
4264 DWARF2 debug info is now supported.
4266 It is now possible to `step' and `next' through calls to `longjmp'.
4268 * Changes in documentation.
4270 All GDB documentation was converted to GFDL, the GNU Free
4271 Documentation License.
4273 Tracepoints-related commands are now fully documented in the GDB
4276 TUI, the Text-mode User Interface, is now documented in the manual.
4278 Tracepoints-related commands are now fully documented in the GDB
4281 The "GDB Internals" manual now has an index. It also includes
4282 documentation of `ui_out' functions, GDB coding standards, x86
4283 hardware watchpoints, and memory region attributes.
4285 * GDB's version number moved to ``version.in''
4287 The Makefile variable VERSION has been replaced by the file
4288 ``version.in''. People creating GDB distributions should update the
4289 contents of this file.
4293 GUD support is now a standard part of the EMACS distribution.
4295 *** Changes in GDB 5.0:
4297 * Improved support for debugging FP programs on x86 targets
4299 Unified and much-improved support for debugging floating-point
4300 programs on all x86 targets. In particular, ``info float'' now
4301 displays the FP registers in the same format on all x86 targets, with
4302 greater level of detail.
4304 * Improvements and bugfixes in hardware-assisted watchpoints
4306 It is now possible to watch array elements, struct members, and
4307 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4308 on x86 targets no longer erroneously trigger when the address is
4311 * Improvements in the native DJGPP version of GDB
4313 The distribution now includes all the scripts and auxiliary files
4314 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4315 machines ``out of the box''.
4317 The DJGPP version can now debug programs that use signals. It is
4318 possible to catch signals that happened in the debuggee, deliver
4319 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4320 would kill the program being debugged.) Programs that hook hardware
4321 interrupts (keyboard, timer, etc.) can also be debugged.
4323 It is now possible to debug DJGPP programs that redirect their
4324 standard handles or switch them to raw (as opposed to cooked) mode, or
4325 even close them. The command ``run < foo > bar'' works as expected,
4326 and ``info terminal'' reports useful information about the debuggee's
4327 terminal, including raw/cooked mode, redirection, etc.
4329 The DJGPP version now uses termios functions for console I/O, which
4330 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4333 DOS-style file names with drive letters are now fully supported by
4336 It is now possible to debug DJGPP programs that switch their working
4337 directory. It is also possible to rerun the debuggee any number of
4338 times without restarting GDB; thus, you can use the same setup,
4339 breakpoints, etc. for many debugging sessions.
4341 * New native configurations
4343 ARM GNU/Linux arm*-*-linux*
4344 PowerPC GNU/Linux powerpc-*-linux*
4348 Motorola MCore mcore-*-*
4349 x86 VxWorks i[3456]86-*-vxworks*
4350 PowerPC VxWorks powerpc-*-vxworks*
4351 TI TMS320C80 tic80-*-*
4353 * OBSOLETE configurations
4355 Altos 3068 m68*-altos-*
4356 Convex c1-*-*, c2-*-*
4358 ARM RISCix arm-*-* (as host)
4361 Configurations that have been declared obsolete will be commented out,
4362 but the code will be left in place. If there is no activity to revive
4363 these configurations before the next release of GDB, the sources will
4364 be permanently REMOVED.
4366 * Gould support removed
4368 Support for the Gould PowerNode and NP1 has been removed.
4370 * New features for SVR4
4372 On SVR4 native platforms (such as Solaris), if you attach to a process
4373 without first loading a symbol file, GDB will now attempt to locate and
4374 load symbols from the running process's executable file.
4376 * Many C++ enhancements
4378 C++ support has been greatly improved. Overload resolution now works properly
4379 in almost all cases. RTTI support is on the way.
4381 * Remote targets can connect to a sub-program
4383 A popen(3) style serial-device has been added. This device starts a
4384 sub-process (such as a stand-alone simulator) and then communicates
4385 with that. The sub-program to run is specified using the syntax
4386 ``|<program> <args>'' vis:
4388 (gdb) set remotedebug 1
4389 (gdb) target extended-remote |mn10300-elf-sim program-args
4391 * MIPS 64 remote protocol
4393 A long standing bug in the mips64 remote protocol where by GDB
4394 expected certain 32 bit registers (ex SR) to be transfered as 32
4395 instead of 64 bits has been fixed.
4397 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4398 added to provide backward compatibility with older versions of GDB.
4400 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4402 The command ``set remotebinarydownload'' command has been replaced by
4403 ``set remote X-packet''. Other commands in ``set remote'' family
4404 include ``set remote P-packet''.
4406 * Breakpoint commands accept ranges.
4408 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4409 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4410 ``tracepoint passcount'' also accepts a range of tracepoints.
4412 * ``apropos'' command added.
4414 The ``apropos'' command searches through command names and
4415 documentation strings, printing out matches, making it much easier to
4416 try to find a command that does what you are looking for.
4420 A new machine oriented interface (MI) has been added to GDB. This
4421 interface is designed for debug environments running GDB as a separate
4422 process. This is part of the long term libGDB project. See the
4423 "GDB/MI" chapter of the GDB manual for further information. It can be
4424 enabled by configuring with:
4426 .../configure --enable-gdbmi
4428 *** Changes in GDB-4.18:
4430 * New native configurations
4432 HP-UX 10.20 hppa*-*-hpux10.20
4433 HP-UX 11.x hppa*-*-hpux11.0*
4434 M68K GNU/Linux m68*-*-linux*
4438 Fujitsu FR30 fr30-*-elf*
4439 Intel StrongARM strongarm-*-*
4440 Mitsubishi D30V d30v-*-*
4442 * OBSOLETE configurations
4444 Gould PowerNode, NP1 np1-*-*, pn-*-*
4446 Configurations that have been declared obsolete will be commented out,
4447 but the code will be left in place. If there is no activity to revive
4448 these configurations before the next release of GDB, the sources will
4449 be permanently REMOVED.
4453 As a compatibility experiment, GDB's source files buildsym.h and
4454 buildsym.c have been converted to pure standard C, no longer
4455 containing any K&R compatibility code. We believe that all systems in
4456 use today either come with a standard C compiler, or have a GCC port
4457 available. If this is not true, please report the affected
4458 configuration to bug-gdb@gnu.org immediately. See the README file for
4459 information about getting a standard C compiler if you don't have one
4464 GDB now uses readline 2.2.
4466 * set extension-language
4468 You can now control the mapping between filename extensions and source
4469 languages by using the `set extension-language' command. For instance,
4470 you can ask GDB to treat .c files as C++ by saying
4471 set extension-language .c c++
4472 The command `info extensions' lists all of the recognized extensions
4473 and their associated languages.
4475 * Setting processor type for PowerPC and RS/6000
4477 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4478 you can use the `set processor' command to specify what variant of the
4479 PowerPC family you are debugging. The command
4483 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4484 following PowerPC and RS6000 variants:
4486 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4487 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4489 403GC IBM PowerPC 403GC
4490 505 Motorola PowerPC 505
4491 860 Motorola PowerPC 860 or 850
4492 601 Motorola PowerPC 601
4493 602 Motorola PowerPC 602
4494 603 Motorola/IBM PowerPC 603 or 603e
4495 604 Motorola PowerPC 604 or 604e
4496 750 Motorola/IBM PowerPC 750 or 750
4498 At the moment, this command just tells GDB what to name the
4499 special-purpose processor registers. Since almost all the affected
4500 registers are inaccessible to user-level programs, this command is
4501 only useful for remote debugging in its present form.
4505 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4506 more extensive support for HP-UX. Added features include shared
4507 library support, kernel threads and hardware watchpoints for 11.00,
4508 support for HP's ANSI C and C++ compilers, and a compatibility mode
4509 for xdb and dbx commands.
4513 HP's donation includes the new concept of catchpoints, which is a
4514 generalization of the old catch command. On HP-UX, it is now possible
4515 to catch exec, fork, and vfork, as well as library loading.
4517 This means that the existing catch command has changed; its first
4518 argument now specifies the type of catch to be set up. See the
4519 output of "help catch" for a list of catchpoint types.
4521 * Debugging across forks
4523 On HP-UX, you can choose which process to debug when a fork() happens
4528 HP has donated a curses-based terminal user interface (TUI). To get
4529 it, build with --enable-tui. Although this can be enabled for any
4530 configuration, at present it only works for native HP debugging.
4532 * GDB remote protocol additions
4534 A new protocol packet 'X' that writes binary data is now available.
4535 Default behavior is to try 'X', then drop back to 'M' if the stub
4536 fails to respond. The settable variable `remotebinarydownload'
4537 allows explicit control over the use of 'X'.
4539 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4540 full 64-bit address. The command
4542 set remoteaddresssize 32
4544 can be used to revert to the old behaviour. For existing remote stubs
4545 the change should not be noticed, as the additional address information
4548 In order to assist in debugging stubs, you may use the maintenance
4549 command `packet' to send any text string to the stub. For instance,
4551 maint packet heythere
4553 sends the packet "$heythere#<checksum>". Note that it is very easy to
4554 disrupt a debugging session by sending the wrong packet at the wrong
4557 The compare-sections command allows you to compare section data on the
4558 target to what is in the executable file without uploading or
4559 downloading, by comparing CRC checksums.
4561 * Tracing can collect general expressions
4563 You may now collect general expressions at tracepoints. This requires
4564 further additions to the target-side stub; see tracepoint.c and
4565 doc/agentexpr.texi for further details.
4567 * mask-address variable for Mips
4569 For Mips targets, you may control the zeroing of the upper 32 bits of
4570 a 64-bit address by entering `set mask-address on'. This is mainly
4571 of interest to users of embedded R4xxx and R5xxx processors.
4573 * Higher serial baud rates
4575 GDB's serial code now allows you to specify baud rates 57600, 115200,
4576 230400, and 460800 baud. (Note that your host system may not be able
4577 to achieve all of these rates.)
4581 The i960 configuration now includes an initial implementation of a
4582 builtin simulator, contributed by Jim Wilson.
4585 *** Changes in GDB-4.17:
4587 * New native configurations
4589 Alpha GNU/Linux alpha*-*-linux*
4590 Unixware 2.x i[3456]86-unixware2*
4591 Irix 6.x mips*-sgi-irix6*
4592 PowerPC GNU/Linux powerpc-*-linux*
4593 PowerPC Solaris powerpcle-*-solaris*
4594 Sparc GNU/Linux sparc-*-linux*
4595 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4599 Argonaut Risc Chip (ARC) arc-*-*
4600 Hitachi H8/300S h8300*-*-*
4601 Matsushita MN10200 w/simulator mn10200-*-*
4602 Matsushita MN10300 w/simulator mn10300-*-*
4603 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4604 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4605 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4606 Mitsubishi D10V w/simulator d10v-*-*
4607 Mitsubishi M32R/D w/simulator m32r-*-elf*
4608 Tsqware Sparclet sparclet-*-*
4609 NEC V850 w/simulator v850-*-*
4611 * New debugging protocols
4613 ARM with RDI protocol arm*-*-*
4614 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4615 DDB and LSI variants of PMON protocol mips*-*-*
4616 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4617 PowerPC with SDS protocol powerpc{,le}-*-eabi
4618 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4622 All configurations can now understand and use the DWARF 2 debugging
4623 format. The choice is automatic, if the symbol file contains DWARF 2
4628 GDB now includes basic Java language support. This support is
4629 only useful with Java compilers that produce native machine code.
4631 * solib-absolute-prefix and solib-search-path
4633 For SunOS and SVR4 shared libraries, you may now set the prefix for
4634 loading absolute shared library symbol files, and the search path for
4635 locating non-absolute shared library symbol files.
4637 * Live range splitting
4639 GDB can now effectively debug code for which GCC has performed live
4640 range splitting as part of its optimization. See gdb/doc/LRS for
4641 more details on the expected format of the stabs information.
4645 GDB's support for the GNU Hurd, including thread debugging, has been
4646 updated to work with current versions of the Hurd.
4650 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4651 instruction set. ARM GDB automatically detects when Thumb
4652 instructions are in use, and adjusts disassembly and backtracing
4657 GDB's MIPS target configurations now handle the MIP16 16-bit
4662 GDB now includes support for overlays; if an executable has been
4663 linked such that multiple sections are based at the same address, GDB
4664 will decide which section to use for symbolic info. You can choose to
4665 control the decision manually, using overlay commands, or implement
4666 additional target-side support and use "overlay load-target" to bring
4667 in the overlay mapping. Do "help overlay" for more detail.
4671 The command "info symbol <address>" displays information about
4672 the symbol at the specified address.
4676 The standard remote protocol now includes an extension that allows
4677 asynchronous collection and display of trace data. This requires
4678 extensive support in the target-side debugging stub. Tracing mode
4679 includes a new interaction mode in GDB and new commands: see the
4680 file tracepoint.c for more details.
4684 Configurations for embedded MIPS now include a simulator contributed
4685 by Cygnus Solutions. The simulator supports the instruction sets
4686 of most MIPS variants.
4690 Sparc configurations may now include the ERC32 simulator contributed
4691 by the European Space Agency. The simulator is not built into
4692 Sparc targets by default; configure with --enable-sim to include it.
4696 For target configurations that may include multiple variants of a
4697 basic architecture (such as MIPS and SH), you may now set the
4698 architecture explicitly. "set arch" sets, "info arch" lists
4699 the possible architectures.
4701 *** Changes in GDB-4.16:
4703 * New native configurations
4705 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4706 M68K NetBSD m68k-*-netbsd*
4707 PowerPC AIX 4.x powerpc-*-aix*
4708 PowerPC MacOS powerpc-*-macos*
4709 PowerPC Windows NT powerpcle-*-cygwin32
4710 RS/6000 AIX 4.x rs6000-*-aix4*
4714 ARM with RDP protocol arm-*-*
4715 I960 with MON960 i960-*-coff
4716 MIPS VxWorks mips*-*-vxworks*
4717 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4718 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4720 Matra Sparclet sparclet-*-*
4724 The powerpc-eabi configuration now includes the PSIM simulator,
4725 contributed by Andrew Cagney, with assistance from Mike Meissner.
4726 PSIM is a very elaborate model of the PowerPC, including not only
4727 basic instruction set execution, but also details of execution unit
4728 performance and I/O hardware. See sim/ppc/README for more details.
4732 GDB now works with Solaris 2.5.
4734 * Windows 95/NT native
4736 GDB will now work as a native debugger on Windows 95 and Windows NT.
4737 To build it from source, you must use the "gnu-win32" environment,
4738 which uses a DLL to emulate enough of Unix to run the GNU tools.
4739 Further information, binaries, and sources are available at
4740 ftp.cygnus.com, under pub/gnu-win32.
4742 * dont-repeat command
4744 If a user-defined command includes the command `dont-repeat', then the
4745 command will not be repeated if the user just types return. This is
4746 useful if the command is time-consuming to run, so that accidental
4747 extra keystrokes don't run the same command many times.
4749 * Send break instead of ^C
4751 The standard remote protocol now includes an option to send a break
4752 rather than a ^C to the target in order to interrupt it. By default,
4753 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4755 * Remote protocol timeout
4757 The standard remote protocol includes a new variable `remotetimeout'
4758 that allows you to set the number of seconds before GDB gives up trying
4759 to read from the target. The default value is 2.
4761 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4763 By default GDB will automatically keep track of objects as they are
4764 loaded and unloaded by the dynamic linker. By using the command `set
4765 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4766 when shared library events occur, thus allowing you to set breakpoints
4767 in shared libraries which are explicitly loaded by the inferior.
4769 Note this feature does not work on hpux8. On hpux9 you must link
4770 /usr/lib/end.o into your program. This feature should work
4771 automatically on hpux10.
4773 * Irix 5.x hardware watchpoint support
4775 Irix 5 configurations now support the use of hardware watchpoints.
4777 * Mips protocol "SYN garbage limit"
4779 When debugging a Mips target using the `target mips' protocol, you
4780 may set the number of characters that GDB will ignore by setting
4781 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4782 every character. The default value is 1050.
4784 * Recording and replaying remote debug sessions
4786 If you set `remotelogfile' to the name of a file, gdb will write to it
4787 a recording of a remote debug session. This recording may then be
4788 replayed back to gdb using "gdbreplay". See gdbserver/README for
4789 details. This is useful when you have a problem with GDB while doing
4790 remote debugging; you can make a recording of the session and send it
4791 to someone else, who can then recreate the problem.
4793 * Speedups for remote debugging
4795 GDB includes speedups for downloading and stepping MIPS systems using
4796 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4797 and more efficient S-record downloading.
4799 * Memory use reductions and statistics collection
4801 GDB now uses less memory and reports statistics about memory usage.
4802 Try the `maint print statistics' command, for example.
4804 *** Changes in GDB-4.15:
4806 * Psymtabs for XCOFF
4808 The symbol reader for AIX GDB now uses partial symbol tables. This
4809 can greatly improve startup time, especially for large executables.
4811 * Remote targets use caching
4813 Remote targets now use a data cache to speed up communication with the
4814 remote side. The data cache could lead to incorrect results because
4815 it doesn't know about volatile variables, thus making it impossible to
4816 debug targets which use memory mapped I/O devices. `set remotecache
4817 off' turns the the data cache off.
4819 * Remote targets may have threads
4821 The standard remote protocol now includes support for multiple threads
4822 in the target system, using new protocol commands 'H' and 'T'. See
4823 gdb/remote.c for details.
4827 If GDB is configured with `--enable-netrom', then it will include
4828 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4829 acts as though it is a bank of ROM on the target board, but you can
4830 write into it over the network. GDB's support consists only of
4831 support for fast loading into the emulated ROM; to debug, you must use
4832 another protocol, such as standard remote protocol. The usual
4833 sequence is something like
4835 target nrom <netrom-hostname>
4837 target remote <netrom-hostname>:1235
4841 GDB now includes support for the Apple Macintosh, as a host only. It
4842 may be run as either an MPW tool or as a standalone application, and
4843 it can debug through the serial port. All the usual GDB commands are
4844 available, but to the target command, you must supply "serial" as the
4845 device type instead of "/dev/ttyXX". See mpw-README in the main
4846 directory for more information on how to build. The MPW configuration
4847 scripts */mpw-config.in support only a few targets, and only the
4848 mips-idt-ecoff target has been tested.
4852 GDB configuration now uses autoconf. This is not user-visible,
4853 but does simplify configuration and building.
4857 GDB now supports hpux10.
4859 *** Changes in GDB-4.14:
4861 * New native configurations
4863 x86 FreeBSD i[345]86-*-freebsd
4864 x86 NetBSD i[345]86-*-netbsd
4865 NS32k NetBSD ns32k-*-netbsd
4866 Sparc NetBSD sparc-*-netbsd
4870 A29K VxWorks a29k-*-vxworks
4871 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4872 CPU32 EST-300 emulator m68*-*-est*
4873 PowerPC ELF powerpc-*-elf
4876 * Alpha OSF/1 support for procfs
4878 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4879 possible to attach to running processes. As the mounting of the /proc
4880 filesystem is optional on the Alpha, GDB automatically determines
4881 the availability of /proc during startup. This can lead to problems
4882 if /proc is unmounted after GDB has been started.
4884 * Arguments to user-defined commands
4886 User commands may accept up to 10 arguments separated by whitespace.
4887 Arguments are accessed within the user command via $arg0..$arg9. A
4890 print $arg0 + $arg1 + $arg2
4892 To execute the command use:
4895 Defines the command "adder" which prints the sum of its three arguments.
4896 Note the arguments are text substitutions, so they may reference variables,
4897 use complex expressions, or even perform inferior function calls.
4899 * New `if' and `while' commands
4901 This makes it possible to write more sophisticated user-defined
4902 commands. Both commands take a single argument, which is the
4903 expression to evaluate, and must be followed by the commands to
4904 execute, one per line, if the expression is nonzero, the list being
4905 terminated by the word `end'. The `if' command list may include an
4906 `else' word, which causes the following commands to be executed only
4907 if the expression is zero.
4909 * Fortran source language mode
4911 GDB now includes partial support for Fortran 77. It will recognize
4912 Fortran programs and can evaluate a subset of Fortran expressions, but
4913 variables and functions may not be handled correctly. GDB will work
4914 with G77, but does not yet know much about symbols emitted by other
4917 * Better HPUX support
4919 Most debugging facilities now work on dynamic executables for HPPAs
4920 running hpux9 or later. You can attach to running dynamically linked
4921 processes, but by default the dynamic libraries will be read-only, so
4922 for instance you won't be able to put breakpoints in them. To change
4923 that behavior do the following before running the program:
4929 This will cause the libraries to be mapped private and read-write.
4930 To revert to the normal behavior, do this:
4936 You cannot set breakpoints or examine data in the library until after
4937 the library is loaded if the function/data symbols do not have
4940 GDB can now also read debug symbols produced by the HP C compiler on
4941 HPPAs (sorry, no C++, Fortran or 68k support).
4943 * Target byte order now dynamically selectable
4945 You can choose which byte order to use with a target system, via the
4946 commands "set endian big" and "set endian little", and you can see the
4947 current setting by using "show endian". You can also give the command
4948 "set endian auto", in which case GDB will use the byte order
4949 associated with the executable. Currently, only embedded MIPS
4950 configurations support dynamic selection of target byte order.
4952 * New DOS host serial code
4954 This version uses DPMI interrupts to handle buffered I/O, so you
4955 no longer need to run asynctsr when debugging boards connected to
4958 *** Changes in GDB-4.13:
4960 * New "complete" command
4962 This lists all the possible completions for the rest of the line, if it
4963 were to be given as a command itself. This is intended for use by emacs.
4965 * Trailing space optional in prompt
4967 "set prompt" no longer adds a space for you after the prompt you set. This
4968 allows you to set a prompt which ends in a space or one that does not.
4970 * Breakpoint hit counts
4972 "info break" now displays a count of the number of times the breakpoint
4973 has been hit. This is especially useful in conjunction with "ignore"; you
4974 can ignore a large number of breakpoint hits, look at the breakpoint info
4975 to see how many times the breakpoint was hit, then run again, ignoring one
4976 less than that number, and this will get you quickly to the last hit of
4979 * Ability to stop printing at NULL character
4981 "set print null-stop" will cause GDB to stop printing the characters of
4982 an array when the first NULL is encountered. This is useful when large
4983 arrays actually contain only short strings.
4985 * Shared library breakpoints
4987 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4988 breakpoints in shared libraries before the executable is run.
4990 * Hardware watchpoints
4992 There is a new hardware breakpoint for the watch command for sparclite
4993 targets. See gdb/sparclite/hw_breakpoint.note.
4995 Hardware watchpoints are also now supported under GNU/Linux.
4999 Annotations have been added. These are for use with graphical interfaces,
5000 and are still experimental. Currently only gdba.el uses these.
5002 * Improved Irix 5 support
5004 GDB now works properly with Irix 5.2.
5006 * Improved HPPA support
5008 GDB now works properly with the latest GCC and GAS.
5010 * New native configurations
5012 Sequent PTX4 i[34]86-sequent-ptx4
5013 HPPA running OSF/1 hppa*-*-osf*
5014 Atari TT running SVR4 m68*-*-sysv4*
5015 RS/6000 LynxOS rs6000-*-lynxos*
5019 OS/9000 i[34]86-*-os9k
5020 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5023 * Hitachi SH7000 and E7000-PC ICE support
5025 There is now support for communicating with the Hitachi E7000-PC ICE.
5026 This is available automatically when GDB is configured for the SH.
5030 As usual, a variety of small fixes and improvements, both generic
5031 and configuration-specific. See the ChangeLog for more detail.
5033 *** Changes in GDB-4.12:
5035 * Irix 5 is now supported
5039 GDB-4.12 on the HPPA has a number of changes which make it unable
5040 to debug the output from the currently released versions of GCC and
5041 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5042 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5043 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5046 *** Changes in GDB-4.11:
5048 * User visible changes:
5052 The "set remotedebug" option is now consistent between the mips remote
5053 target, remote targets using the gdb-specific protocol, UDI (AMD's
5054 debug protocol for the 29k) and the 88k bug monitor. It is now an
5055 integer specifying a debug level (normally 0 or 1, but 2 means more
5056 debugging info for the mips target).
5058 * DEC Alpha native support
5060 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5061 debug info, but GDB works fairly well with the DEC compiler and should
5062 work with a future GCC release. See the README file for a few
5063 Alpha-specific notes.
5065 * Preliminary thread implementation
5067 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5069 * LynxOS native and target support for 386
5071 This release has been hosted on LynxOS 2.2, and also can be configured
5072 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5075 * Improvements in C++ mangling/demangling.
5077 This release has much better g++ debugging, specifically in name
5078 mangling/demangling, virtual function calls, print virtual table,
5079 call methods, ...etc.
5081 *** Changes in GDB-4.10:
5083 * User visible changes:
5085 Remote debugging using the GDB-specific (`target remote') protocol now
5086 supports the `load' command. This is only useful if you have some
5087 other way of getting the stub to the target system, and you can put it
5088 somewhere in memory where it won't get clobbered by the download.
5090 Filename completion now works.
5092 When run under emacs mode, the "info line" command now causes the
5093 arrow to point to the line specified. Also, "info line" prints
5094 addresses in symbolic form (as well as hex).
5096 All vxworks based targets now support a user settable option, called
5097 vxworks-timeout. This option represents the number of seconds gdb
5098 should wait for responses to rpc's. You might want to use this if
5099 your vxworks target is, perhaps, a slow software simulator or happens
5100 to be on the far side of a thin network line.
5104 This release contains support for using a DEC alpha as a GDB host for
5105 cross debugging. Native alpha debugging is not supported yet.
5108 *** Changes in GDB-4.9:
5112 This is the first GDB release which is accompanied by a matching testsuite.
5113 The testsuite requires installation of dejagnu, which should be available
5114 via ftp from most sites that carry GNU software.
5118 'Cfront' style demangling has had its name changed to 'ARM' style, to
5119 emphasize that it was written from the specifications in the C++ Annotated
5120 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5121 disclaimers, it still generated too much confusion with users attempting to
5122 use gdb with AT&T cfront.
5126 GDB now uses a standard remote interface to a simulator library.
5127 So far, the library contains simulators for the Zilog Z8001/2, the
5128 Hitachi H8/300, H8/500 and Super-H.
5130 * New targets supported
5132 H8/300 simulator h8300-hitachi-hms or h8300hms
5133 H8/500 simulator h8500-hitachi-hms or h8500hms
5134 SH simulator sh-hitachi-hms or sh
5135 Z8000 simulator z8k-zilog-none or z8ksim
5136 IDT MIPS board over serial line mips-idt-ecoff
5138 Cross-debugging to GO32 targets is supported. It requires a custom
5139 version of the i386-stub.c module which is integrated with the
5140 GO32 memory extender.
5142 * New remote protocols
5144 MIPS remote debugging protocol.
5146 * New source languages supported
5148 This version includes preliminary support for Chill, a Pascal like language
5149 used by telecommunications companies. Chill support is also being integrated
5150 into the GNU compiler, but we don't know when it will be publically available.
5153 *** Changes in GDB-4.8:
5155 * HP Precision Architecture supported
5157 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5158 version of this support was available as a set of patches from the
5159 University of Utah. GDB does not support debugging of programs
5160 compiled with the HP compiler, because HP will not document their file
5161 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5162 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5164 Many problems in the preliminary version have been fixed.
5166 * Faster and better demangling
5168 We have improved template demangling and fixed numerous bugs in the GNU style
5169 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5170 character types (wchar_t) are now supported. Demangling of each symbol is now
5171 only done once, and is cached when the symbol table for a file is read in.
5172 This results in a small increase in memory usage for C programs, a moderate
5173 increase in memory usage for C++ programs, and a fantastic speedup in
5176 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5177 from the specifications in the Annotated Reference Manual, which AT&T's
5178 compiler does not actually implement.
5180 * G++ multiple inheritance compiler problem
5182 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5183 inheritance lattices was reworked to properly discover ambiguities. We
5184 recently found an example which causes this new algorithm to fail in a
5185 very subtle way, producing bad debug information for those classes.
5186 The file 'gcc.patch' (in this directory) can be applied to gcc to
5187 circumvent the problem. A future GCC release will contain a complete
5190 The previous G++ debug info problem (mentioned below for the gdb-4.7
5191 release) is fixed in gcc version 2.3.2.
5193 * Improved configure script
5195 The `configure' script will now attempt to guess your system type if
5196 you don't supply a host system type. The old scheme of supplying a
5197 host system triplet is preferable over using this. All the magic is
5198 done in the new `config.guess' script. Examine it for details.
5200 We have also brought our configure script much more in line with the FSF's
5201 version. It now supports the --with-xxx options. In particular,
5202 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5203 The resulting GDB will not be able to read arbitrary object file formats --
5204 only the format ``expected'' to be used on the configured target system.
5205 We hope to make this the default in a future release.
5207 * Documentation improvements
5209 There's new internal documentation on how to modify GDB, and how to
5210 produce clean changes to the code. We implore people to read it
5211 before submitting changes.
5213 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5214 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5215 `info' files are also provided. To build `info' files from scratch,
5216 you will need the latest `makeinfo' release, which will be available in
5217 a future texinfo-X.Y release.
5219 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5220 We're not sure exactly which versions have this problem, but it has
5221 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5222 or better. If that isn't possible, there is a patch in
5223 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5224 around this problem.
5228 GDB now supports array constants that can be used in expressions typed in by
5229 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5230 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5233 The new directory `gdb/sparclite' contains a program that demonstrates
5234 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5236 * New native hosts supported
5238 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5239 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5241 * New targets supported
5243 AMD 29k family via UDI a29k-amd-udi or udi29k
5245 * New file formats supported
5247 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5248 HPUX core files, and SCO 3.2v2 core files.
5252 Attaching to processes now works again; thanks for the many bug reports.
5254 We have also stomped on a bunch of core dumps caused by
5255 printf_filtered("%s") problems.
5257 We eliminated a copyright problem on the rpc and ptrace header files
5258 for VxWorks, which was discovered at the last minute during the 4.7
5259 release. You should now be able to build a VxWorks GDB.
5261 You can now interrupt gdb while an attached process is running. This
5262 will cause the attached process to stop, and give control back to GDB.
5264 We fixed problems caused by using too many file descriptors
5265 for reading symbols from object files and libraries. This was
5266 especially a problem for programs that used many (~100) shared
5269 The `step' command now only enters a subroutine if there is line number
5270 information for the subroutine. Otherwise it acts like the `next'
5271 command. Previously, `step' would enter subroutines if there was
5272 any debugging information about the routine. This avoids problems
5273 when using `cc -g1' on MIPS machines.
5275 * Internal improvements
5277 GDB's internal interfaces have been improved to make it easier to support
5278 debugging of multiple languages in the future.
5280 GDB now uses a common structure for symbol information internally.
5281 Minimal symbols (derived from linkage symbols in object files), partial
5282 symbols (from a quick scan of debug information), and full symbols
5283 contain a common subset of information, making it easier to write
5284 shared code that handles any of them.
5286 * New command line options
5288 We now accept --silent as an alias for --quiet.
5292 The memory-mapped-malloc library is now licensed under the GNU Library
5293 General Public License.
5295 *** Changes in GDB-4.7:
5297 * Host/native/target split
5299 GDB has had some major internal surgery to untangle the support for
5300 hosts and remote targets. Now, when you configure GDB for a remote
5301 target, it will no longer load in all of the support for debugging
5302 local programs on the host. When fully completed and tested, this will
5303 ensure that arbitrary host/target combinations are possible.
5305 The primary conceptual shift is to separate the non-portable code in
5306 GDB into three categories. Host specific code is required any time GDB
5307 is compiled on that host, regardless of the target. Target specific
5308 code relates to the peculiarities of the target, but can be compiled on
5309 any host. Native specific code is everything else: it can only be
5310 built when the host and target are the same system. Child process
5311 handling and core file support are two common `native' examples.
5313 GDB's use of /proc for controlling Unix child processes is now cleaner.
5314 It has been split out into a single module under the `target_ops' vector,
5315 plus two native-dependent functions for each system that uses /proc.
5317 * New hosts supported
5319 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5320 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5321 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5323 * New targets supported
5325 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5326 68030 and CPU32 m68030-*-*, m68332-*-*
5328 * New native hosts supported
5330 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5331 (386bsd is not well tested yet)
5332 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5334 * New file formats supported
5336 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5337 supports reading of `a.out.adobe' object files, which are an a.out
5338 format extended with minimal information about multiple sections.
5342 `show copying' is the same as the old `info copying'.
5343 `show warranty' is the same as `info warrantee'.
5344 These were renamed for consistency. The old commands continue to work.
5346 `info handle' is a new alias for `info signals'.
5348 You can now define pre-command hooks, which attach arbitrary command
5349 scripts to any command. The commands in the hook will be executed
5350 prior to the user's command. You can also create a hook which will be
5351 executed whenever the program stops. See gdb.texinfo.
5355 We now deal with Cfront style name mangling, and can even extract type
5356 info from mangled symbols. GDB can automatically figure out which
5357 symbol mangling style your C++ compiler uses.
5359 Calling of methods and virtual functions has been improved as well.
5363 The crash that occured when debugging Sun Ansi-C compiled binaries is
5364 fixed. This was due to mishandling of the extra N_SO stabs output
5367 We also finally got Ultrix 4.2 running in house, and fixed core file
5368 support, with help from a dozen people on the net.
5370 John M. Farrell discovered that the reason that single-stepping was so
5371 slow on all of the Mips based platforms (primarily SGI and DEC) was
5372 that we were trying to demangle and lookup a symbol used for internal
5373 purposes on every instruction that was being stepped through. Changing
5374 the name of that symbol so that it couldn't be mistaken for a C++
5375 mangled symbol sped things up a great deal.
5377 Rich Pixley sped up symbol lookups in general by getting much smarter
5378 about when C++ symbol mangling is necessary. This should make symbol
5379 completion (TAB on the command line) much faster. It's not as fast as
5380 we'd like, but it's significantly faster than gdb-4.6.
5384 A new user controllable variable 'call_scratch_address' can
5385 specify the location of a scratch area to be used when GDB
5386 calls a function in the target. This is necessary because the
5387 usual method of putting the scratch area on the stack does not work
5388 in systems that have separate instruction and data spaces.
5390 We integrated changes to support the 29k UDI (Universal Debugger
5391 Interface), but discovered at the last minute that we didn't have all
5392 of the appropriate copyright paperwork. We are working with AMD to
5393 resolve this, and hope to have it available soon.
5397 We have sped up the remote serial line protocol, especially for targets
5398 with lots of registers. It now supports a new `expedited status' ('T')
5399 message which can be used in place of the existing 'S' status message.
5400 This allows the remote stub to send only the registers that GDB
5401 needs to make a quick decision about single-stepping or conditional
5402 breakpoints, eliminating the need to fetch the entire register set for
5403 each instruction being stepped through.
5405 The GDB remote serial protocol now implements a write-through cache for
5406 registers, only re-reading the registers if the target has run.
5408 There is also a new remote serial stub for SPARC processors. You can
5409 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5410 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5411 processor with a serial port.
5415 Configure.in files have become much easier to read and modify. A new
5416 `table driven' format makes it more obvious what configurations are
5417 supported, and what files each one uses.
5421 There is a new opcodes library which will eventually contain all of the
5422 disassembly routines and opcode tables. At present, it only contains
5423 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5424 disassembler (binutils/objdump) to share these routines.
5426 The libiberty library is now copylefted under the GNU Library General
5427 Public License. This allows more liberal use, and was done so libg++
5428 can use it. This makes no difference to GDB, since the Library License
5429 grants all the rights from the General Public License.
5433 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5434 reference to the stabs symbol info used by the debugger. It is (as far
5435 as we know) the only published document on this fascinating topic. We
5436 encourage you to read it, compare it to the stabs information on your
5437 system, and send improvements on the document in general (to
5438 bug-gdb@prep.ai.mit.edu).
5440 And, of course, many bugs have been fixed.
5443 *** Changes in GDB-4.6:
5445 * Better support for C++ function names
5447 GDB now accepts as input the "demangled form" of C++ overloaded function
5448 names and member function names, and can do command completion on such names
5449 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5450 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5451 Make use of command completion, it is your friend.
5453 GDB also now accepts a variety of C++ mangled symbol formats. They are
5454 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5455 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5456 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5457 for the list of formats.
5459 * G++ symbol mangling problem
5461 Recent versions of gcc have a bug in how they emit debugging information for
5462 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5463 directory) can be applied to gcc to fix the problem. Alternatively, if you
5464 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5465 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5466 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5469 * New 'maintenance' command
5471 All of the commands related to hacking GDB internals have been moved out of
5472 the main command set, and now live behind the 'maintenance' command. This
5473 can also be abbreviated as 'mt'. The following changes were made:
5475 dump-me -> maintenance dump-me
5476 info all-breakpoints -> maintenance info breakpoints
5477 printmsyms -> maintenance print msyms
5478 printobjfiles -> maintenance print objfiles
5479 printpsyms -> maintenance print psymbols
5480 printsyms -> maintenance print symbols
5482 The following commands are new:
5484 maintenance demangle Call internal GDB demangler routine to
5485 demangle a C++ link name and prints the result.
5486 maintenance print type Print a type chain for a given symbol
5488 * Change to .gdbinit file processing
5490 We now read the $HOME/.gdbinit file before processing the argv arguments
5491 (e.g. reading symbol files or core files). This allows global parameters to
5492 be set, which will apply during the symbol reading. The ./.gdbinit is still
5493 read after argv processing.
5495 * New hosts supported
5497 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5499 GNU/Linux support i386-unknown-linux or linux
5501 We are also including code to support the HP/PA running BSD and HPUX. This
5502 is almost guaranteed not to work, as we didn't have time to test or build it
5503 for this release. We are including it so that the more adventurous (or
5504 masochistic) of you can play with it. We also had major problems with the
5505 fact that the compiler that we got from HP doesn't support the -g option.
5508 * New targets supported
5510 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5512 * More smarts about finding #include files
5514 GDB now remembers the compilation directory for all include files, and for
5515 all files from which C is generated (like yacc and lex sources). This
5516 greatly improves GDB's ability to find yacc/lex sources, and include files,
5517 especially if you are debugging your program from a directory different from
5518 the one that contains your sources.
5520 We also fixed a bug which caused difficulty with listing and setting
5521 breakpoints in include files which contain C code. (In the past, you had to
5522 try twice in order to list an include file that you hadn't looked at before.)
5524 * Interesting infernals change
5526 GDB now deals with arbitrary numbers of sections, where the symbols for each
5527 section must be relocated relative to that section's landing place in the
5528 target's address space. This work was needed to support ELF with embedded
5529 stabs used by Solaris-2.0.
5531 * Bug fixes (of course!)
5533 There have been loads of fixes for the following things:
5534 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5535 i960, stabs, DOS(GO32), procfs, etc...
5537 See the ChangeLog for details.
5539 *** Changes in GDB-4.5:
5541 * New machines supported (host and target)
5543 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5545 SGI Irix-4.x mips-sgi-irix4 or iris4
5547 * New malloc package
5549 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5550 Mmalloc is capable of handling mutiple heaps of memory. It is also
5551 capable of saving a heap to a file, and then mapping it back in later.
5552 This can be used to greatly speedup the startup of GDB by using a
5553 pre-parsed symbol table which lives in a mmalloc managed heap. For
5554 more details, please read mmalloc/mmalloc.texi.
5558 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5559 'help info proc' for details.
5561 * MIPS ecoff symbol table format
5563 The code that reads MIPS symbol table format is now supported on all hosts.
5564 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5567 * File name changes for MS-DOS
5569 Many files in the config directories have been renamed to make it easier to
5570 support GDB on MS-DOSe systems (which have very restrictive file name
5571 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5572 environment) is close to working but has some remaining problems. Note
5573 that debugging of DOS programs is not supported, due to limitations
5574 in the ``operating system'', but it can be used to host cross-debugging.
5576 * Cross byte order fixes
5578 Many fixes have been made to support cross debugging of Sparc and MIPS
5579 targets from hosts whose byte order differs.
5581 * New -mapped and -readnow options
5583 If memory-mapped files are available on your system through the 'mmap'
5584 system call, you can use the -mapped option on the `file' or
5585 `symbol-file' commands to cause GDB to write the symbols from your
5586 program into a reusable file. If the program you are debugging is
5587 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5588 Future GDB debugging sessions will notice the presence of this file,
5589 and will quickly map in symbol information from it, rather than reading
5590 the symbol table from the executable program. Using the '-mapped'
5591 option in a GDB `file' or `symbol-file' command has the same effect as
5592 starting GDB with the '-mapped' command-line option.
5594 You can cause GDB to read the entire symbol table immediately by using
5595 the '-readnow' option with any of the commands that load symbol table
5596 information (or on the GDB command line). This makes the command
5597 slower, but makes future operations faster.
5599 The -mapped and -readnow options are typically combined in order to
5600 build a `fred.syms' file that contains complete symbol information.
5601 A simple GDB invocation to do nothing but build a `.syms' file for future
5604 gdb -batch -nx -mapped -readnow programname
5606 The `.syms' file is specific to the host machine on which GDB is run.
5607 It holds an exact image of GDB's internal symbol table. It cannot be
5608 shared across multiple host platforms.
5610 * longjmp() handling
5612 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5613 siglongjmp() without losing control. This feature has not yet been ported to
5614 all systems. It currently works on many 386 platforms, all MIPS-based
5615 platforms (SGI, DECstation, etc), and Sun3/4.
5619 Preliminary work has been put in to support the new Solaris OS from Sun. At
5620 this time, it can control and debug processes, but it is not capable of
5625 As always, many many bug fixes. The major areas were with g++, and mipsread.
5626 People using the MIPS-based platforms should experience fewer mysterious
5627 crashes and trashed symbol tables.
5629 *** Changes in GDB-4.4:
5631 * New machines supported (host and target)
5633 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5635 BSD Reno on Vax vax-dec-bsd
5636 Ultrix on Vax vax-dec-ultrix
5638 * New machines supported (target)
5640 AMD 29000 embedded, using EBMON a29k-none-none
5644 GDB continues to improve its handling of C++. `References' work better.
5645 The demangler has also been improved, and now deals with symbols mangled as
5646 per the Annotated C++ Reference Guide.
5648 GDB also now handles `stabs' symbol information embedded in MIPS
5649 `ecoff' symbol tables. Since the ecoff format was not easily
5650 extensible to handle new languages such as C++, this appeared to be a
5651 good way to put C++ debugging info into MIPS binaries. This option
5652 will be supported in the GNU C compiler, version 2, when it is
5655 * New features for SVR4
5657 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5658 shared libraries. Debugging dynamically linked programs should present
5659 only minor differences from debugging statically linked programs.
5661 The `info proc' command will print out information about any process
5662 on an SVR4 system (including the one you are debugging). At the moment,
5663 it prints the address mappings of the process.
5665 If you bring up GDB on another SVR4 system, please send mail to
5666 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5668 * Better dynamic linking support in SunOS
5670 Reading symbols from shared libraries which contain debugging symbols
5671 now works properly. However, there remain issues such as automatic
5672 skipping of `transfer vector' code during function calls, which
5673 make it harder to debug code in a shared library, than to debug the
5674 same code linked statically.
5678 GDB is now using the latest `getopt' routines from the FSF. This
5679 version accepts the -- prefix for options with long names. GDB will
5680 continue to accept the old forms (-option and +option) as well.
5681 Various single letter abbreviations for options have been explicity
5682 added to the option table so that they won't get overshadowed in the
5683 future by other options that begin with the same letter.
5687 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5688 Many assorted bugs have been handled. Many more remain to be handled.
5689 See the various ChangeLog files (primarily in gdb and bfd) for details.
5692 *** Changes in GDB-4.3:
5694 * New machines supported (host and target)
5696 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5697 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5698 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5700 * Almost SCO Unix support
5702 We had hoped to support:
5703 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5704 (except for core file support), but we discovered very late in the release
5705 that it has problems with process groups that render gdb unusable. Sorry
5706 about that. I encourage people to fix it and post the fixes.
5708 * Preliminary ELF and DWARF support
5710 GDB can read ELF object files on System V Release 4, and can handle
5711 debugging records for C, in DWARF format, in ELF files. This support
5712 is preliminary. If you bring up GDB on another SVR4 system, please
5713 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5718 GDB now uses the latest `readline' library. One user-visible change
5719 is that two tabs will list possible command completions, which previously
5720 required typing M-? (meta-question mark, or ESC ?).
5724 The `stepi' bug that many of you noticed has been squashed.
5725 Many bugs in C++ have been handled. Many more remain to be handled.
5726 See the various ChangeLog files (primarily in gdb and bfd) for details.
5728 * State of the MIPS world (in case you wondered):
5730 GDB can understand the symbol tables emitted by the compilers
5731 supplied by most vendors of MIPS-based machines, including DEC. These
5732 symbol tables are in a format that essentially nobody else uses.
5734 Some versions of gcc come with an assembler post-processor called
5735 mips-tfile. This program is required if you want to do source-level
5736 debugging of gcc-compiled programs. I believe FSF does not ship
5737 mips-tfile with gcc version 1, but it will eventually come with gcc
5740 Debugging of g++ output remains a problem. g++ version 1.xx does not
5741 really support it at all. (If you're lucky, you should be able to get
5742 line numbers and stack traces to work, but no parameters or local
5743 variables.) With some work it should be possible to improve the
5746 When gcc version 2 is released, you will have somewhat better luck.
5747 However, even then you will get confusing results for inheritance and
5750 We will eventually provide full debugging of g++ output on
5751 DECstations. This will probably involve some kind of stabs-in-ecoff
5752 encapulation, but the details have not been worked out yet.
5755 *** Changes in GDB-4.2:
5757 * Improved configuration
5759 Only one copy of `configure' exists now, and it is not self-modifying.
5760 Porting BFD is simpler.
5764 The `step' and `next' commands now only stop at the first instruction
5765 of a source line. This prevents the multiple stops that used to occur
5766 in switch statements, for-loops, etc. `Step' continues to stop if a
5767 function that has debugging information is called within the line.
5771 Lots of small bugs fixed. More remain.
5773 * New host supported (not target)
5775 Intel 386 PC clone running Mach i386-none-mach
5778 *** Changes in GDB-4.1:
5780 * Multiple source language support
5782 GDB now has internal scaffolding to handle several source languages.
5783 It determines the type of each source file from its filename extension,
5784 and will switch expression parsing and number formatting to match the
5785 language of the function in the currently selected stack frame.
5786 You can also specifically set the language to be used, with
5787 `set language c' or `set language modula-2'.
5791 GDB now has preliminary support for the GNU Modula-2 compiler,
5792 currently under development at the State University of New York at
5793 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5794 continue through the fall of 1991 and into 1992.
5796 Other Modula-2 compilers are currently not supported, and attempting to
5797 debug programs compiled with them will likely result in an error as the
5798 symbol table is read. Feel free to work on it, though!
5800 There are hooks in GDB for strict type checking and range checking,
5801 in the `Modula-2 philosophy', but they do not currently work.
5805 GDB can now write to executable and core files (e.g. patch
5806 a variable's value). You must turn this switch on, specify
5807 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5808 by assigning a new value to a variable. Modifications take
5811 * Automatic SunOS shared library reading
5813 When you run your program, GDB automatically determines where its
5814 shared libraries (if any) have been loaded, and reads their symbols.
5815 The `share' command is no longer needed. This also works when
5816 examining core files.
5820 You can specify the number of lines that the `list' command shows.
5823 * New machines supported (host and target)
5825 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5826 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5827 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5829 * New hosts supported (not targets)
5831 IBM RT/PC: romp-ibm-aix or rtpc
5833 * New targets supported (not hosts)
5835 AMD 29000 embedded with COFF a29k-none-coff
5836 AMD 29000 embedded with a.out a29k-none-aout
5837 Ultracomputer remote kernel debug a29k-nyu-kern
5839 * New remote interfaces
5845 *** Changes in GDB-4.0:
5849 Wide output is wrapped at good places to make the output more readable.
5851 Gdb now supports cross-debugging from a host machine of one type to a
5852 target machine of another type. Communication with the target system
5853 is over serial lines. The ``target'' command handles connecting to the
5854 remote system; the ``load'' command will download a program into the
5855 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5856 also supports debugging of realtime processes running under VxWorks,
5857 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5858 stub on the target system.
5860 New CPUs supported include the AMD 29000 and Intel 960.
5862 GDB now reads object files and symbol tables via a ``binary file''
5863 library, which allows a single copy of GDB to debug programs of multiple
5864 object file types such as a.out and coff.
5866 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5867 refcard.dvi and refcard.ps are available to format it).
5870 * Control-Variable user interface simplified
5872 All variables that control the operation of the debugger can be set
5873 by the ``set'' command, and displayed by the ``show'' command.
5875 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5876 ``Show prompt'' produces the response:
5877 Gdb's prompt is new-gdb=>.
5879 What follows are the NEW set commands. The command ``help set'' will
5880 print a complete list of old and new set commands. ``help set FOO''
5881 will give a longer description of the variable FOO. ``show'' will show
5882 all of the variable descriptions and their current settings.
5884 confirm on/off: Enables warning questions for operations that are
5885 hard to recover from, e.g. rerunning the program while
5886 it is already running. Default is ON.
5888 editing on/off: Enables EMACS style command line editing
5889 of input. Previous lines can be recalled with
5890 control-P, the current line can be edited with control-B,
5891 you can search for commands with control-R, etc.
5894 history filename NAME: NAME is where the gdb command history
5895 will be stored. The default is .gdb_history,
5896 or the value of the environment variable
5899 history size N: The size, in commands, of the command history. The
5900 default is 256, or the value of the environment variable
5903 history save on/off: If this value is set to ON, the history file will
5904 be saved after exiting gdb. If set to OFF, the
5905 file will not be saved. The default is OFF.
5907 history expansion on/off: If this value is set to ON, then csh-like
5908 history expansion will be performed on
5909 command line input. The default is OFF.
5911 radix N: Sets the default radix for input and output. It can be set
5912 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5913 in the current radix, so "set radix 10" is always a no-op.
5915 height N: This integer value is the number of lines on a page. Default
5916 is 24, the current `stty rows'' setting, or the ``li#''
5917 setting from the termcap entry matching the environment
5920 width N: This integer value is the number of characters on a line.
5921 Default is 80, the current `stty cols'' setting, or the ``co#''
5922 setting from the termcap entry matching the environment
5925 Note: ``set screensize'' is obsolete. Use ``set height'' and
5926 ``set width'' instead.
5928 print address on/off: Print memory addresses in various command displays,
5929 such as stack traces and structure values. Gdb looks
5930 more ``symbolic'' if you turn this off; it looks more
5931 ``machine level'' with it on. Default is ON.
5933 print array on/off: Prettyprint arrays. New convenient format! Default
5936 print demangle on/off: Print C++ symbols in "source" form if on,
5939 print asm-demangle on/off: Same, for assembler level printouts
5942 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5945 * Support for Epoch Environment.
5947 The epoch environment is a version of Emacs v18 with windowing. One
5948 new command, ``inspect'', is identical to ``print'', except that if you
5949 are running in the epoch environment, the value is printed in its own
5953 * Support for Shared Libraries
5955 GDB can now debug programs and core files that use SunOS shared libraries.
5956 Symbols from a shared library cannot be referenced
5957 before the shared library has been linked with the program (this
5958 happens after you type ``run'' and before the function main() is entered).
5959 At any time after this linking (including when examining core files
5960 from dynamically linked programs), gdb reads the symbols from each
5961 shared library when you type the ``sharedlibrary'' command.
5962 It can be abbreviated ``share''.
5964 sharedlibrary REGEXP: Load shared object library symbols for files
5965 matching a unix regular expression. No argument
5966 indicates to load symbols for all shared libraries.
5968 info sharedlibrary: Status of loaded shared libraries.
5973 A watchpoint stops execution of a program whenever the value of an
5974 expression changes. Checking for this slows down execution
5975 tremendously whenever you are in the scope of the expression, but is
5976 quite useful for catching tough ``bit-spreader'' or pointer misuse
5977 problems. Some machines such as the 386 have hardware for doing this
5978 more quickly, and future versions of gdb will use this hardware.
5980 watch EXP: Set a watchpoint (breakpoint) for an expression.
5982 info watchpoints: Information about your watchpoints.
5984 delete N: Deletes watchpoint number N (same as breakpoints).
5985 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5986 enable N: Re-enables watchpoint number N (same as breakpoints).
5989 * C++ multiple inheritance
5991 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5994 * C++ exception handling
5996 Gdb now supports limited C++ exception handling. Besides the existing
5997 ability to breakpoint on an exception handler, gdb can breakpoint on
5998 the raising of an exception (before the stack is peeled back to the
6001 catch FOO: If there is a FOO exception handler in the dynamic scope,
6002 set a breakpoint to catch exceptions which may be raised there.
6003 Multiple exceptions (``catch foo bar baz'') may be caught.
6005 info catch: Lists all exceptions which may be caught in the
6006 current stack frame.
6009 * Minor command changes
6011 The command ``call func (arg, arg, ...)'' now acts like the print
6012 command, except it does not print or save a value if the function's result
6013 is void. This is similar to dbx usage.
6015 The ``up'' and ``down'' commands now always print the frame they end up
6016 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6017 frames without printing.
6019 * New directory command
6021 'dir' now adds directories to the FRONT of the source search path.
6022 The path starts off empty. Source files that contain debug information
6023 about the directory in which they were compiled can be found even
6024 with an empty path; Sun CC and GCC include this information. If GDB can't
6025 find your source file in the current directory, type "dir .".
6027 * Configuring GDB for compilation
6029 For normal use, type ``./configure host''. See README or gdb.texinfo
6032 GDB now handles cross debugging. If you are remotely debugging between
6033 two different machines, type ``./configure host -target=targ''.
6034 Host is the machine where GDB will run; targ is the machine
6035 where the program that you are debugging will run.