1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.9
6 * GDB now honors the content of the file /proc/PID/coredump_filter
7 (PID is the process ID) on GNU/Linux systems. This file can be used
8 to specify the types of memory mappings that will be included in a
9 corefile. For more information, please refer to the manual page of
10 "core(5)". GDB also has a new command: "set use-coredump-filter
11 on|off". It allows to set whether GDB will read the content of the
12 /proc/PID/coredump_filter file when generating a corefile.
14 * The "info os" command on GNU/Linux can now display information on
16 "info os cpus" Listing of all cpus/cores on the system
18 * GDB has two new commands: "set serial parity odd|even|none" and
19 "show serial parity". These allows to set or show parity for the
22 * The "info source" command now displays the producer string if it was
23 present in the debug info. This typically includes the compiler version
24 and may include things like its command line arguments.
26 * The "info dll", an alias of the "info sharedlibrary" command,
27 is now available on all platforms.
29 * Directory names supplied to the "set sysroot" commands may be
30 prefixed with "target:" to tell GDB to access shared libraries from
31 the target system, be it local or remote. This replaces the prefix
32 "remote:". The default sysroot has been changed from "" to
33 "target:". "remote:" is automatically converted to "target:" for
34 backward compatibility.
36 * The system root specified by "set sysroot" will be prepended to the
37 filename of the main executable (if reported to GDB as absolute by
38 the operating system) when starting processes remotely, and when
39 attaching to already-running local or remote processes.
41 * GDB now supports automatic location and retrieval of executable
42 files from remote targets. Remote debugging can now be initiated
43 using only a "target remote" or "target extended-remote" command
44 (no "set sysroot" or "file" commands are required). See "New remote
47 * The "dump" command now supports verilog hex format.
49 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
53 ** gdb.Objfile objects have a new attribute "username",
54 which is the name of the objfile as specified by the user,
55 without, for example, resolving symlinks.
56 ** You can now write frame unwinders in Python.
57 ** gdb.Type objects have a new method "optimized_out",
58 returning optimized out gdb.Value instance of this type.
59 ** Xmethods can now specify a result type.
63 maint print symbol-cache
64 Print the contents of the symbol cache.
66 maint print symbol-cache-statistics
67 Print statistics of symbol cache usage.
69 maint flush-symbol-cache
70 Flush the contents of the symbol cache.
74 Start branch trace recording using Branch Trace Store (BTS) format.
80 Set the maximum number of candidates to be considered during
81 completion. The default value is 200. This limit allows GDB
82 to avoid generating large completion lists, the computation of
83 which can cause the debugger to become temporarily unresponsive.
85 maint set symbol-cache-size
86 maint show symbol-cache-size
87 Control the size of the symbol cache.
89 set|show record btrace bts buffer-size
90 Set and show the size of the ring buffer used for branch tracing in
92 The obtained size may differ from the requested size. Use "info
93 record" to see the obtained buffer size.
95 * The command 'thread apply all' can now support new option '-ascending'
96 to call its specified command for all threads in ascending order.
98 * Python/Guile scripting
100 ** GDB now supports auto-loading of Python/Guile scripts contained in the
101 special section named `.debug_gdb_scripts'.
105 qXfer:btrace-conf:read
106 Return the branch trace configuration for the current thread.
108 Qbtrace-conf:bts:size
109 Set the requested ring buffer size for branch tracing in BTS format.
112 Indicates a memory breakpoint instruction was executed, irrespective
113 of whether it was GDB that planted the breakpoint or the breakpoint
114 is hardcoded in the program. This is required for correct non-stop
118 Indicates the target stopped for a hardware breakpoint. This is
119 required for correct non-stop mode operation.
122 Return information about files on the remote system.
125 Return the full absolute name of the file that was executed to
126 create a process running on the remote system.
128 * The info record command now shows the recording format and the
129 branch tracing configuration for the current thread when using
130 the btrace record target.
131 For the BTS format, it shows the ring buffer size.
133 * GDB now has support for DTrace USDT (Userland Static Defined
134 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
136 * GDB now supports access to vector registers on S/390 GNU/Linux
139 * Removed command line options
141 -xdb HP-UX XDB compatibility mode.
143 * Removed targets and native configurations
145 HP/PA running HP-UX hppa*-*-hpux*
146 Itanium running HP-UX ia64-*-hpux*
148 *** Changes in GDB 7.9
150 * GDB now supports hardware watchpoints on x86 GNU Hurd.
154 ** You can now access frame registers from Python scripts.
155 ** New attribute 'producer' for gdb.Symtab objects.
156 ** gdb.Objfile objects have a new attribute "progspace",
157 which is the gdb.Progspace object of the containing program space.
158 ** gdb.Objfile objects have a new attribute "owner".
159 ** gdb.Objfile objects have a new attribute "build_id",
160 which is the build ID generated when the file was built.
161 ** gdb.Objfile objects have a new method "add_separate_debug_file".
162 ** A new event "gdb.clear_objfiles" has been added, triggered when
163 selecting a new file to debug.
164 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
165 ** New function gdb.lookup_objfile.
167 New events which are triggered when GDB modifies the state of the
170 ** gdb.events.inferior_call_pre: Function call is about to be made.
171 ** gdb.events.inferior_call_post: Function call has just been made.
172 ** gdb.events.memory_changed: A memory location has been altered.
173 ** gdb.events.register_changed: A register has been altered.
175 * New Python-based convenience functions:
177 ** $_caller_is(name [, number_of_frames])
178 ** $_caller_matches(regexp [, number_of_frames])
179 ** $_any_caller_is(name [, number_of_frames])
180 ** $_any_caller_matches(regexp [, number_of_frames])
182 * GDB now supports the compilation and injection of source code into
183 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
184 to compile the source code to object code, and if successful, inject
185 and execute that code within the current context of the inferior.
186 Currently the C language is supported. The commands used to
187 interface with this new feature are:
189 compile code [-raw|-r] [--] [source code]
190 compile file [-raw|-r] filename
194 demangle [-l language] [--] name
195 Demangle "name" in the specified language, or the current language
196 if elided. This command is renamed from the "maint demangle" command.
197 The latter is kept as a no-op to avoid "maint demangle" being interpreted
198 as "maint demangler-warning".
200 queue-signal signal-name-or-number
201 Queue a signal to be delivered to the thread when it is resumed.
203 add-auto-load-scripts-directory directory
204 Add entries to the list of directories from which to load auto-loaded
207 maint print user-registers
208 List all currently available "user" registers.
210 compile code [-r|-raw] [--] [source code]
211 Compile, inject, and execute in the inferior the executable object
212 code produced by compiling the provided source code.
214 compile file [-r|-raw] filename
215 Compile and inject into the inferior the executable object code
216 produced by compiling the source code stored in the filename
219 * On resume, GDB now always passes the signal the program had stopped
220 for to the thread the signal was sent to, even if the user changed
221 threads before resuming. Previously GDB would often (but not
222 always) deliver the signal to the thread that happens to be current
225 * Conversely, the "signal" command now consistently delivers the
226 requested signal to the current thread. GDB now asks for
227 confirmation if the program had stopped for a signal and the user
228 switched threads meanwhile.
230 * "breakpoint always-inserted" modes "off" and "auto" merged.
232 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
233 won't remove breakpoints from the target until all threads stop,
234 even in non-stop mode. The "auto" mode has been removed, and "off"
235 is now the default mode.
239 set debug symbol-lookup
240 show debug symbol-lookup
241 Control display of debugging info regarding symbol lookup.
245 ** The -list-thread-groups command outputs an exit-code field for
246 inferiors that have exited.
250 MIPS SDE mips*-sde*-elf*
254 Support for these obsolete configurations has been removed.
256 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
257 SGI Irix-5.x mips-*-irix5*
258 SGI Irix-6.x mips-*-irix6*
259 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
260 VAX running Ultrix vax-*-ultrix*
262 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
263 and "assf"), have been removed. Use the "sharedlibrary" command, or
264 its alias "share", instead.
266 *** Changes in GDB 7.8
268 * New command line options
271 This is an alias for the --data-directory option.
273 * GDB supports printing and modifying of variable length automatic arrays
274 as specified in ISO C99.
276 * The ARM simulator now supports instruction level tracing
277 with or without disassembly.
281 GDB now has support for scripting using Guile. Whether this is
282 available is determined at configure time.
283 Guile version 2.0 or greater is required.
284 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
286 * New commands (for set/show, see "New options" below)
290 Invoke CODE by passing it to the Guile interpreter.
294 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
296 info auto-load guile-scripts [regexp]
297 Print the list of automatically loaded Guile scripts.
299 * The source command is now capable of sourcing Guile scripts.
300 This feature is dependent on the debugger being built with Guile support.
304 set print symbol-loading (off|brief|full)
305 show print symbol-loading
306 Control whether to print informational messages when loading symbol
307 information for a file. The default is "full", but when debugging
308 programs with large numbers of shared libraries the amount of output
311 set guile print-stack (none|message|full)
312 show guile print-stack
313 Show a stack trace when an error is encountered in a Guile script.
315 set auto-load guile-scripts (on|off)
316 show auto-load guile-scripts
317 Control auto-loading of Guile script files.
319 maint ada set ignore-descriptive-types (on|off)
320 maint ada show ignore-descriptive-types
321 Control whether the debugger should ignore descriptive types in Ada
322 programs. The default is not to ignore the descriptive types. See
323 the user manual for more details on descriptive types and the intended
324 usage of this option.
326 set auto-connect-native-target
328 Control whether GDB is allowed to automatically connect to the
329 native target for the run, attach, etc. commands when not connected
330 to any target yet. See also "target native" below.
332 set record btrace replay-memory-access (read-only|read-write)
333 show record btrace replay-memory-access
334 Control what memory accesses are allowed during replay.
336 maint set target-async (on|off)
337 maint show target-async
338 This controls whether GDB targets operate in synchronous or
339 asynchronous mode. Normally the default is asynchronous, if it is
340 available; but this can be changed to more easily debug problems
341 occurring only in synchronous mode.
343 set mi-async (on|off)
345 Control whether MI asynchronous mode is preferred. This supersedes
346 "set target-async" of previous GDB versions.
348 * "set target-async" is deprecated as a CLI option and is now an alias
349 for "set mi-async" (only puts MI into async mode).
351 * Background execution commands (e.g., "c&", "s&", etc.) are now
352 possible ``out of the box'' if the target supports them. Previously
353 the user would need to explicitly enable the possibility with the
354 "set target-async on" command.
356 * New features in the GDB remote stub, GDBserver
358 ** New option --debug-format=option1[,option2,...] allows one to add
359 additional text to each output. At present only timestamps
360 are supported: --debug-format=timestamps.
361 Timestamps can also be turned on with the
362 "monitor set debug-format timestamps" command from GDB.
364 * The 'record instruction-history' command now starts counting instructions
365 at one. This also affects the instruction ranges reported by the
366 'record function-call-history' command when given the /i modifier.
368 * The command 'record function-call-history' supports a new modifier '/c' to
369 indent the function names based on their call stack depth.
370 The fields for the '/i' and '/l' modifier have been reordered.
371 The source line range is now prefixed with 'at'.
372 The instruction range is now prefixed with 'inst'.
373 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
374 "record instruction-history" and "list" commands.
376 * The ranges given as arguments to the 'record function-call-history' and
377 'record instruction-history' commands are now inclusive.
379 * The btrace record target now supports the 'record goto' command.
380 For locations inside the execution trace, the back trace is computed
381 based on the information stored in the execution trace.
383 * The btrace record target supports limited reverse execution and replay.
384 The target does not record data and therefore does not allow reading
387 * The "catch syscall" command now works on s390*-linux* targets.
389 * The "compare-sections" command is no longer specific to target
390 remote. It now works with all targets.
392 * All native targets are now consistently called "native".
393 Consequently, the "target child", "target GNU", "target djgpp",
394 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
395 commands have been replaced with "target native". The QNX/NTO port
396 leaves the "procfs" target in place and adds a "native" target for
397 consistency with other ports. The impact on users should be minimal
398 as these commands previously either throwed an error, or were
399 no-ops. The target's name is visible in the output of the following
400 commands: "help target", "info target", "info files", "maint print
403 * The "target native" command now connects to the native target. This
404 can be used to launch native programs even when "set
405 auto-connect-native-target" is set to off.
407 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
409 * Support for Intel(R) AVX-512 registers on GNU/Linux.
410 Support displaying and modifying Intel(R) AVX-512 registers
411 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
415 qXfer:btrace:read's annex
416 The qXfer:btrace:read packet supports a new annex 'delta' to read
417 branch trace incrementally.
421 ** Valid Python operations on gdb.Value objects representing
422 structs/classes invoke the corresponding overloaded operators if
424 ** New `Xmethods' feature in the Python API. Xmethods are
425 additional methods or replacements for existing methods of a C++
426 class. This feature is useful for those cases where a method
427 defined in C++ source code could be inlined or optimized out by
428 the compiler, making it unavailable to GDB.
431 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
433 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
434 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
435 its alias "share", instead.
437 * The commands "set remotebaud" and "show remotebaud" are no longer
438 supported. Use "set serial baud" and "show serial baud" (respectively)
443 ** A new option "-gdb-set mi-async" replaces "-gdb-set
444 target-async". The latter is left as a deprecated alias of the
445 former for backward compatibility. If the target supports it,
446 CLI background execution commands are now always possible by
447 default, independently of whether the frontend stated a
448 preference for asynchronous execution with "-gdb-set mi-async".
449 Previously "-gdb-set target-async off" affected both MI execution
450 commands and CLI execution commands.
452 *** Changes in GDB 7.7
454 * Improved support for process record-replay and reverse debugging on
455 arm*-linux* targets. Support for thumb32 and syscall instruction
456 recording has been added.
458 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
460 * GDB now supports Fission DWP file format version 2.
461 http://gcc.gnu.org/wiki/DebugFission
463 * New convenience function "$_isvoid", to check whether an expression
464 is void. A void expression is an expression where the type of the
465 result is "void". For example, some convenience variables may be
466 "void" when evaluated (e.g., "$_exitcode" before the execution of
467 the program being debugged; or an undefined convenience variable).
468 Another example, when calling a function whose return type is
471 * The "maintenance print objfiles" command now takes an optional regexp.
473 * The "catch syscall" command now works on arm*-linux* targets.
475 * GDB now consistently shows "<not saved>" when printing values of
476 registers the debug info indicates have not been saved in the frame
477 and there's nowhere to retrieve them from
478 (callee-saved/call-clobbered registers):
483 (gdb) info registers rax
486 Before, the former would print "<optimized out>", and the latter
487 "*value not available*".
489 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
494 ** Frame filters and frame decorators have been added.
495 ** Temporary breakpoints are now supported.
496 ** Line tables representation has been added.
497 ** New attribute 'parent_type' for gdb.Field objects.
498 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
499 ** New attribute 'name' for gdb.Type objects.
503 Nios II ELF nios2*-*-elf
504 Nios II GNU/Linux nios2*-*-linux
505 Texas Instruments MSP430 msp430*-*-elf
507 * Removed native configurations
509 Support for these a.out NetBSD and OpenBSD obsolete configurations has
510 been removed. ELF variants of these configurations are kept supported.
512 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
513 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
514 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
515 i[34567]86-*-openbsd3.[0-3]
516 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
517 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
518 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
522 Like "catch throw", but catches a re-thrown exception.
524 Renamed from old "maint check-symtabs".
526 Perform consistency checks on symtabs.
528 Expand symtabs matching an optional regexp.
531 Display the details of GDB configure-time options.
533 maint set|show per-command
534 maint set|show per-command space
535 maint set|show per-command time
536 maint set|show per-command symtab
537 Enable display of per-command gdb resource usage.
539 remove-symbol-file FILENAME
540 remove-symbol-file -a ADDRESS
541 Remove a symbol file added via add-symbol-file. The file to remove
542 can be identified by its filename or by an address that lies within
543 the boundaries of this symbol file in memory.
546 info exceptions REGEXP
547 Display the list of Ada exceptions defined in the program being
548 debugged. If provided, only the exceptions whose names match REGEXP
553 set debug symfile off|on
555 Control display of debugging info regarding reading symbol files and
556 symbol tables within those files
558 set print raw frame-arguments
559 show print raw frame-arguments
560 Set/show whether to print frame arguments in raw mode,
561 disregarding any defined pretty-printers.
563 set remote trace-status-packet
564 show remote trace-status-packet
565 Set/show the use of remote protocol qTStatus packet.
569 Control display of debugging messages related to Nios II targets.
573 Control whether target-assisted range stepping is enabled.
575 set startup-with-shell
576 show startup-with-shell
577 Specifies whether Unix child processes are started via a shell or
582 Use the target memory cache for accesses to the code segment. This
583 improves performance of remote debugging (particularly disassembly).
585 * You can now use a literal value 'unlimited' for options that
586 interpret 0 or -1 as meaning "unlimited". E.g., "set
587 trace-buffer-size unlimited" is now an alias for "set
588 trace-buffer-size -1" and "set height unlimited" is now an alias for
591 * The "set debug symtab-create" debugging option of GDB has been changed to
592 accept a verbosity level. 0 means "off", 1 provides basic debugging
593 output, and values of 2 or greater provides more verbose output.
595 * New command-line options
597 Display the details of GDB configure-time options.
599 * The command 'tsave' can now support new option '-ctf' to save trace
600 buffer in Common Trace Format.
602 * Newly installed $prefix/bin/gcore acts as a shell interface for the
605 * GDB now implements the the C++ 'typeid' operator.
607 * The new convenience variable $_exception holds the exception being
608 thrown or caught at an exception-related catchpoint.
610 * The exception-related catchpoints, like "catch throw", now accept a
611 regular expression which can be used to filter exceptions by type.
613 * The new convenience variable $_exitsignal is automatically set to
614 the terminating signal number when the program being debugged dies
615 due to an uncaught signal.
619 ** All MI commands now accept an optional "--language" option.
620 Support for this feature can be verified by using the "-list-features"
621 command, which should contain "language-option".
623 ** The new command -info-gdb-mi-command allows the user to determine
624 whether a GDB/MI command is supported or not.
626 ** The "^error" result record returned when trying to execute an undefined
627 GDB/MI command now provides a variable named "code" whose content is the
628 "undefined-command" error code. Support for this feature can be verified
629 by using the "-list-features" command, which should contain
630 "undefined-command-error-code".
632 ** The -trace-save MI command can optionally save trace buffer in Common
635 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
637 ** The command -data-list-register-values now accepts an optional
638 "--skip-unavailable" option. When used, only the available registers
641 ** The new command -trace-frame-collected dumps collected variables,
642 computed expressions, tvars, memory and registers in a traceframe.
644 ** The commands -stack-list-locals, -stack-list-arguments and
645 -stack-list-variables now accept an option "--skip-unavailable".
646 When used, only the available locals or arguments are displayed.
648 ** The -exec-run command now accepts an optional "--start" option.
649 When used, the command follows the same semantics as the "start"
650 command, stopping the program's execution at the start of its
651 main subprogram. Support for this feature can be verified using
652 the "-list-features" command, which should contain
653 "exec-run-start-option".
655 ** The new commands -catch-assert and -catch-exceptions insert
656 catchpoints stopping the program when Ada exceptions are raised.
658 ** The new command -info-ada-exceptions provides the equivalent of
659 the new "info exceptions" command.
661 * New system-wide configuration scripts
662 A GDB installation now provides scripts suitable for use as system-wide
663 configuration scripts for the following systems:
667 * GDB now supports target-assigned range stepping with remote targets.
668 This improves the performance of stepping source lines by reducing
669 the number of control packets from/to GDB. See "New remote packets"
672 * GDB now understands the element 'tvar' in the XML traceframe info.
673 It has the id of the collected trace state variables.
675 * On S/390 targets that provide the transactional-execution feature,
676 the program interruption transaction diagnostic block (TDB) is now
677 represented as a number of additional "registers" in GDB.
683 The vCont packet supports a new 'r' action, that tells the remote
684 stub to step through an address range itself, without GDB
685 involvemement at each single-step.
687 qXfer:libraries-svr4:read's annex
688 The previously unused annex of the qXfer:libraries-svr4:read packet
689 is now used to support passing an argument list. The remote stub
690 reports support for this argument list to GDB's qSupported query.
691 The defined arguments are "start" and "prev", used to reduce work
692 necessary for library list updating, resulting in significant
695 * New features in the GDB remote stub, GDBserver
697 ** GDBserver now supports target-assisted range stepping. Currently
698 enabled on x86/x86_64 GNU/Linux targets.
700 ** GDBserver now adds element 'tvar' in the XML in the reply to
701 'qXfer:traceframe-info:read'. It has the id of the collected
702 trace state variables.
704 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
707 * New 'z' formatter for printing and examining memory, this displays the
708 value as hexadecimal zero padded on the left to the size of the type.
710 * GDB can now use Windows x64 unwinding data.
712 * The "set remotebaud" command has been replaced by "set serial baud".
713 Similarly, "show remotebaud" has been replaced by "show serial baud".
714 The "set remotebaud" and "show remotebaud" commands are still available
715 to provide backward compatibility with older versions of GDB.
717 *** Changes in GDB 7.6
719 * Target record has been renamed to record-full.
720 Record/replay is now enabled with the "record full" command.
721 This also affects settings that are associated with full record/replay
722 that have been moved from "set/show record" to "set/show record full":
724 set|show record full insn-number-max
725 set|show record full stop-at-limit
726 set|show record full memory-query
728 * A new record target "record-btrace" has been added. The new target
729 uses hardware support to record the control-flow of a process. It
730 does not support replaying the execution, but it implements the
731 below new commands for investigating the recorded execution log.
732 This new recording method can be enabled using:
736 The "record-btrace" target is only available on Intel Atom processors
737 and requires a Linux kernel 2.6.32 or later.
739 * Two new commands have been added for record/replay to give information
740 about the recorded execution without having to replay the execution.
741 The commands are only supported by "record btrace".
743 record instruction-history prints the execution history at
744 instruction granularity
746 record function-call-history prints the execution history at
749 * New native configurations
751 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
752 FreeBSD/powerpc powerpc*-*-freebsd
753 x86_64/Cygwin x86_64-*-cygwin*
754 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
758 ARM AArch64 aarch64*-*-elf
759 ARM AArch64 GNU/Linux aarch64*-*-linux
760 Lynx 178 PowerPC powerpc-*-lynx*178
761 x86_64/Cygwin x86_64-*-cygwin*
762 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
764 * If the configured location of system.gdbinit file (as given by the
765 --with-system-gdbinit option at configure time) is in the
766 data-directory (as specified by --with-gdb-datadir at configure
767 time) or in one of its subdirectories, then GDB will look for the
768 system-wide init file in the directory specified by the
769 --data-directory command-line option.
771 * New command line options:
773 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
774 other initialization files, unlike -nx which disables all of them.
776 * Removed command line options
778 -epoch This was used by the gdb mode in Epoch, an ancient fork of
781 * The 'ptype' and 'whatis' commands now accept an argument to control
784 * 'info proc' now works on some core files.
788 ** Vectors can be created with gdb.Type.vector.
790 ** Python's atexit.register now works in GDB.
792 ** Types can be pretty-printed via a Python API.
794 ** Python 3 is now supported (in addition to Python 2.4 or later)
796 ** New class gdb.Architecture exposes GDB's internal representation
797 of architecture in the Python API.
799 ** New method Frame.architecture returns the gdb.Architecture object
800 corresponding to the frame's architecture.
802 * New Python-based convenience functions:
804 ** $_memeq(buf1, buf2, length)
805 ** $_streq(str1, str2)
807 ** $_regex(str, regex)
809 * The 'cd' command now defaults to using '~' (the home directory) if not
812 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
813 default for GCC since November 2000.
815 * The command 'forward-search' can now be abbreviated as 'fo'.
817 * The command 'info tracepoints' can now display 'installed on target'
818 or 'not installed on target' for each non-pending location of tracepoint.
820 * New configure options
822 --enable-libmcheck/--disable-libmcheck
823 By default, development versions are built with -lmcheck on hosts
824 that support it, in order to help track memory corruption issues.
825 Release versions, on the other hand, are built without -lmcheck
826 by default. The --enable-libmcheck/--disable-libmcheck configure
827 options allow the user to override that default.
828 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
829 This configure option allows the user to build GDB with
830 libbabeltrace using which GDB can read Common Trace Format data.
832 * New commands (for set/show, see "New options" below)
835 Catch signals. This is similar to "handle", but allows commands and
836 conditions to be attached.
839 List the BFDs known to GDB.
841 python-interactive [command]
843 Start a Python interactive prompt, or evaluate the optional command
844 and print the result of expressions.
847 "py" is a new alias for "python".
849 enable type-printer [name]...
850 disable type-printer [name]...
851 Enable or disable type printers.
855 ** For the Renesas Super-H architecture, the "regs" command has been removed
856 (has been deprecated in GDB 7.5), and "info all-registers" should be used
861 set print type methods (on|off)
862 show print type methods
863 Control whether method declarations are displayed by "ptype".
864 The default is to show them.
866 set print type typedefs (on|off)
867 show print type typedefs
868 Control whether typedef definitions are displayed by "ptype".
869 The default is to show them.
871 set filename-display basename|relative|absolute
872 show filename-display
873 Control the way in which filenames is displayed.
874 The default is "relative", which preserves previous behavior.
876 set trace-buffer-size
877 show trace-buffer-size
878 Request target to change the size of trace buffer.
880 set remote trace-buffer-size-packet auto|on|off
881 show remote trace-buffer-size-packet
882 Control the use of the remote protocol `QTBuffer:size' packet.
886 Control display of debugging messages related to ARM AArch64.
889 set debug coff-pe-read
890 show debug coff-pe-read
891 Control display of debugging messages related to reading of COFF/PE
896 Control display of debugging messages related to Mach-O symbols
899 set debug notification
900 show debug notification
901 Control display of debugging info for async remote notification.
905 ** Command parameter changes are now notified using new async record
906 "=cmd-param-changed".
907 ** Trace frame changes caused by command "tfind" are now notified using
908 new async record "=traceframe-changed".
909 ** The creation, deletion and modification of trace state variables
910 are now notified using new async records "=tsv-created",
911 "=tsv-deleted" and "=tsv-modified".
912 ** The start and stop of process record are now notified using new
913 async record "=record-started" and "=record-stopped".
914 ** Memory changes are now notified using new async record
916 ** The data-disassemble command response will include a "fullname" field
917 containing the absolute file name when source has been requested.
918 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
919 command, to allow pattern filling of memory areas.
920 ** New commands "-catch-load"/"-catch-unload" added for intercepting
921 library load/unload events.
922 ** The response to breakpoint commands and breakpoint async records
923 includes an "installed" field containing a boolean state about each
924 non-pending tracepoint location is whether installed on target or not.
925 ** Output of the "-trace-status" command includes a "trace-file" field
926 containing the name of the trace file being examined. This field is
927 optional, and only present when examining a trace file.
928 ** The "fullname" field is now always present along with the "file" field,
929 even if the file cannot be found by GDB.
931 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
932 You must have the LZMA library available when configuring GDB for this
933 feature to be enabled. For more information, see:
934 http://fedoraproject.org/wiki/Features/MiniDebugInfo
939 Set the size of trace buffer. The remote stub reports support for this
940 packet to gdb's qSupported query.
943 Enable Branch Trace Store (BTS)-based branch tracing for the current
944 thread. The remote stub reports support for this packet to gdb's
948 Disable branch tracing for the current thread. The remote stub reports
949 support for this packet to gdb's qSupported query.
952 Read the traced branches for the current thread. The remote stub
953 reports support for this packet to gdb's qSupported query.
955 *** Changes in GDB 7.5
957 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
958 for more x32 ABI info.
960 * GDB now supports access to MIPS DSP registers on Linux targets.
962 * GDB now supports debugging microMIPS binaries.
964 * The "info os" command on GNU/Linux can now display information on
965 several new classes of objects managed by the operating system:
966 "info os procgroups" lists process groups
967 "info os files" lists file descriptors
968 "info os sockets" lists internet-domain sockets
969 "info os shm" lists shared-memory regions
970 "info os semaphores" lists semaphores
971 "info os msg" lists message queues
972 "info os modules" lists loaded kernel modules
974 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
975 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
976 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
977 options and inspect the probe arguments using the new $_probe_arg family
978 of convenience variables. You can obtain more information about SystemTap
979 in <http://sourceware.org/systemtap/>.
981 * GDB now supports reversible debugging on ARM, it allows you to
982 debug basic ARM and THUMB instructions, and provides
983 record/replay support.
985 * The option "symbol-reloading" has been deleted as it is no longer used.
989 ** GDB commands implemented in Python can now be put in command class
992 ** The "maint set python print-stack on|off" is now deleted.
994 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
995 apply "flag enum"-style pretty-printing to any enum.
997 ** gdb.lookup_symbol can now work when there is no current frame.
999 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1000 the source at which the symbol was defined.
1002 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1003 method 'value'. The former indicates whether the symbol needs a
1004 frame in order to compute its value, and the latter computes the
1007 ** A new method 'referenced_value' on gdb.Value objects which can
1008 dereference pointer as well as C++ reference values.
1010 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1011 which return the global and static blocks (as gdb.Block objects),
1012 of the underlying symbol table, respectively.
1014 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1015 object associated with a PC value.
1017 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1018 of the address range occupied by code for the current source line.
1020 * Go language support.
1021 GDB now supports debugging programs written in the Go programming
1024 * GDBserver now supports stdio connections.
1025 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1027 * The binary "gdbtui" can no longer be built or installed.
1028 Use "gdb -tui" instead.
1030 * GDB will now print "flag" enums specially. A flag enum is one where
1031 all the enumerator values have no bits in common when pairwise
1032 "and"ed. When printing a value whose type is a flag enum, GDB will
1033 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1034 (gdb) print (enum E) 3
1037 * The filename part of a linespec will now match trailing components
1038 of a source file name. For example, "break gcc/expr.c:1000" will
1039 now set a breakpoint in build/gcc/expr.c, but not
1040 build/libcpp/expr.c.
1042 * The "info proc" and "generate-core-file" commands will now also
1043 work on remote targets connected to GDBserver on Linux.
1045 * The command "info catch" has been removed. It has been disabled
1046 since December 2007.
1048 * The "catch exception" and "catch assert" commands now accept
1049 a condition at the end of the command, much like the "break"
1050 command does. For instance:
1052 (gdb) catch exception Constraint_Error if Barrier = True
1054 Previously, it was possible to add a condition to such catchpoints,
1055 but it had to be done as a second step, after the catchpoint had been
1056 created, using the "condition" command.
1058 * The "info static-tracepoint-marker" command will now also work on
1059 native Linux targets with in-process agent.
1061 * GDB can now set breakpoints on inlined functions.
1063 * The .gdb_index section has been updated to include symbols for
1064 inlined functions. GDB will ignore older .gdb_index sections by
1065 default, which could cause symbol files to be loaded more slowly
1066 until their .gdb_index sections can be recreated. The new command
1067 "set use-deprecated-index-sections on" will cause GDB to use any older
1068 .gdb_index sections it finds. This will restore performance, but the
1069 ability to set breakpoints on inlined functions will be lost in symbol
1070 files with older .gdb_index sections.
1072 The .gdb_index section has also been updated to record more information
1073 about each symbol. This speeds up the "info variables", "info functions"
1074 and "info types" commands when used with programs having the .gdb_index
1075 section, as well as speeding up debugging with shared libraries using
1076 the .gdb_index section.
1078 * Ada support for GDB/MI Variable Objects has been added.
1080 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1085 ** New command -info-os is the MI equivalent of "info os".
1087 ** Output logs ("set logging" and related) now include MI output.
1091 ** "set use-deprecated-index-sections on|off"
1092 "show use-deprecated-index-sections on|off"
1093 Controls the use of deprecated .gdb_index sections.
1095 ** "catch load" and "catch unload" can be used to stop when a shared
1096 library is loaded or unloaded, respectively.
1098 ** "enable count" can be used to auto-disable a breakpoint after
1101 ** "info vtbl" can be used to show the virtual method tables for
1102 C++ and Java objects.
1104 ** "explore" and its sub commands "explore value" and "explore type"
1105 can be used to recursively explore values and types of
1106 expressions. These commands are available only if GDB is
1107 configured with '--with-python'.
1109 ** "info auto-load" shows status of all kinds of auto-loaded files,
1110 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1111 sequences of commands files, "info auto-load python-scripts"
1112 shows status of auto-loading Python script files,
1113 "info auto-load local-gdbinit" shows status of loading init file
1114 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1115 status of inferior specific thread debugging shared library loading.
1117 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1118 and "show auto-load-scripts" commands have been deprecated, use their
1119 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1120 and "show auto-load python-scripts" counterparts instead.
1122 ** "dprintf location,format,args..." creates a dynamic printf, which
1123 is basically a breakpoint that does a printf and immediately
1124 resumes your program's execution, so it is like a printf that you
1125 can insert dynamically at runtime instead of at compiletime.
1127 ** "set print symbol"
1129 Controls whether GDB attempts to display the symbol, if any,
1130 corresponding to addresses it prints. This defaults to "on", but
1131 you can set it to "off" to restore GDB's previous behavior.
1133 * Deprecated commands
1135 ** For the Renesas Super-H architecture, the "regs" command has been
1136 deprecated, and "info all-registers" should be used instead.
1140 Renesas RL78 rl78-*-elf
1141 HP OpenVMS ia64 ia64-hp-openvms*
1143 * GDBserver supports evaluation of breakpoint conditions. When
1144 support is advertised by GDBserver, GDB may be told to send the
1145 breakpoint conditions in bytecode form to GDBserver. GDBserver
1146 will only report the breakpoint trigger to GDB when its condition
1151 set mips compression
1152 show mips compression
1153 Select the compressed ISA encoding used in functions that have no symbol
1154 information available. The encoding can be set to either of:
1157 and is updated automatically from ELF file flags if available.
1159 set breakpoint condition-evaluation
1160 show breakpoint condition-evaluation
1161 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1162 GDBserver ("target"). Default option "auto" chooses the most efficient
1164 This option can improve debugger efficiency depending on the speed of the
1168 Disable auto-loading globally.
1171 Show auto-loading setting of all kinds of auto-loaded files.
1173 set auto-load gdb-scripts on|off
1174 show auto-load gdb-scripts
1175 Control auto-loading of GDB canned sequences of commands files.
1177 set auto-load python-scripts on|off
1178 show auto-load python-scripts
1179 Control auto-loading of Python script files.
1181 set auto-load local-gdbinit on|off
1182 show auto-load local-gdbinit
1183 Control loading of init file (.gdbinit) from current directory.
1185 set auto-load libthread-db on|off
1186 show auto-load libthread-db
1187 Control auto-loading of inferior specific thread debugging shared library.
1189 set auto-load scripts-directory <dir1>[:<dir2>...]
1190 show auto-load scripts-directory
1191 Set a list of directories from which to load auto-loaded scripts.
1192 Automatically loaded Python scripts and GDB scripts are located in one
1193 of the directories listed by this option.
1194 The delimiter (':' above) may differ according to the host platform.
1196 set auto-load safe-path <dir1>[:<dir2>...]
1197 show auto-load safe-path
1198 Set a list of directories from which it is safe to auto-load files.
1199 The delimiter (':' above) may differ according to the host platform.
1201 set debug auto-load on|off
1202 show debug auto-load
1203 Control display of debugging info for auto-loading the files above.
1205 set dprintf-style gdb|call|agent
1207 Control the way in which a dynamic printf is performed; "gdb"
1208 requests a GDB printf command, while "call" causes dprintf to call a
1209 function in the inferior. "agent" requests that the target agent
1210 (such as GDBserver) do the printing.
1212 set dprintf-function <expr>
1213 show dprintf-function
1214 set dprintf-channel <expr>
1215 show dprintf-channel
1216 Set the function and optional first argument to the call when using
1217 the "call" style of dynamic printf.
1219 set disconnected-dprintf on|off
1220 show disconnected-dprintf
1221 Control whether agent-style dynamic printfs continue to be in effect
1222 after GDB disconnects.
1224 * New configure options
1226 --with-auto-load-dir
1227 Configure default value for the 'set auto-load scripts-directory'
1228 setting above. It defaults to '$debugdir:$datadir/auto-load',
1229 $debugdir representing global debugging info directories (available
1230 via 'show debug-file-directory') and $datadir representing GDB's data
1231 directory (available via 'show data-directory').
1233 --with-auto-load-safe-path
1234 Configure default value for the 'set auto-load safe-path' setting
1235 above. It defaults to the --with-auto-load-dir setting.
1237 --without-auto-load-safe-path
1238 Set 'set auto-load safe-path' to '/', effectively disabling this
1241 * New remote packets
1243 z0/z1 conditional breakpoints extension
1245 The z0/z1 breakpoint insertion packets have been extended to carry
1246 a list of conditional expressions over to the remote stub depending on the
1247 condition evaluation mode. The use of this extension can be controlled
1248 via the "set remote conditional-breakpoints-packet" command.
1252 Specify the signals which the remote stub may pass to the debugged
1253 program without GDB involvement.
1255 * New command line options
1257 --init-command=FILE, -ix Like --command, -x but execute it
1258 before loading inferior.
1259 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1260 execute it before loading inferior.
1262 *** Changes in GDB 7.4
1264 * GDB now handles ambiguous linespecs more consistently; the existing
1265 FILE:LINE support has been expanded to other types of linespecs. A
1266 breakpoint will now be set on all matching locations in all
1267 inferiors, and locations will be added or removed according to
1270 * GDB now allows you to skip uninteresting functions and files when
1271 stepping with the "skip function" and "skip file" commands.
1273 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1274 and "show remote hardware-watchpoint-length-limit". These allows to
1275 set or show the maximum length limit (in bytes) of a remote
1276 target hardware watchpoint.
1278 This allows e.g. to use "unlimited" hardware watchpoints with the
1279 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1280 watchpoints are slower than real hardware watchpoints but are
1281 significantly faster than gdb software watchpoints.
1285 ** The register_pretty_printer function in module gdb.printing now takes
1286 an optional `replace' argument. If True, the new printer replaces any
1289 ** The "maint set python print-stack on|off" command has been
1290 deprecated and will be deleted in GDB 7.5.
1291 A new command: "set python print-stack none|full|message" has
1292 replaced it. Additionally, the default for "print-stack" is
1293 now "message", which just prints the error message without
1296 ** A prompt substitution hook (prompt_hook) is now available to the
1299 ** A new Python module, gdb.prompt has been added to the GDB Python
1300 modules library. This module provides functionality for
1301 escape sequences in prompts (used by set/show
1302 extended-prompt). These escape sequences are replaced by their
1303 corresponding value.
1305 ** Python commands and convenience-functions located in
1306 'data-directory'/python/gdb/command and
1307 'data-directory'/python/gdb/function are now automatically loaded
1310 ** Blocks now provide four new attributes. global_block and
1311 static_block will return the global and static blocks
1312 respectively. is_static and is_global are boolean attributes
1313 that indicate if the block is one of those two types.
1315 ** Symbols now provide the "type" attribute, the type of the symbol.
1317 ** The "gdb.breakpoint" function has been deprecated in favor of
1320 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1321 of a function. This class is based on the "finish" command
1322 available in the CLI.
1324 ** Type objects for struct and union types now allow access to
1325 the fields using standard Python dictionary (mapping) methods.
1326 For example, "some_type['myfield']" now works, as does
1327 "some_type.items()".
1329 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1332 ** A new function, "deep_items" has been added to the gdb.types
1333 module in the GDB Python modules library. This function returns
1334 an iterator over the fields of a struct or union type. Unlike
1335 the standard Python "iteritems" method, it will recursively traverse
1336 any anonymous fields.
1340 ** "*stopped" events can report several new "reason"s, such as
1343 ** Breakpoint changes are now notified using new async records, like
1344 "=breakpoint-modified".
1346 ** New command -ada-task-info.
1348 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1349 $sdir specifies the default system locations of shared libraries.
1350 $pdir specifies the directory where the libpthread used by the application
1353 GDB no longer looks in $sdir and $pdir after it has searched the directories
1354 mentioned in libthread-db-search-path. If you want to search those
1355 directories, they must be specified in libthread-db-search-path.
1356 The default value of libthread-db-search-path on GNU/Linux and Solaris
1357 systems is now "$sdir:$pdir".
1359 $pdir is not supported by gdbserver, it is currently ignored.
1360 $sdir is supported by gdbserver.
1362 * New configure option --with-iconv-bin.
1363 When using the internationalization support like the one in the GNU C
1364 library, GDB will invoke the "iconv" program to get a list of supported
1365 character sets. If this program lives in a non-standard location, one can
1366 use this option to specify where to find it.
1368 * When natively debugging programs on PowerPC BookE processors running
1369 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1370 watchpoints, which specify a mask in addition to an address to watch.
1371 The mask specifies that some bits of an address (the bits which are
1372 reset in the mask) should be ignored when matching the address accessed
1373 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1374 section in the user manual for more details.
1376 * The new option --once causes GDBserver to stop listening for connections once
1377 the first connection is made. The listening port used by GDBserver will
1378 become available after that.
1380 * New commands "info macros" and "alias" have been added.
1382 * New function parameters suffix @entry specifies value of function parameter
1383 at the time the function got called. Entry values are available only since
1389 "!" is now an alias of the "shell" command.
1390 Note that no space is needed between "!" and SHELL COMMAND.
1394 watch EXPRESSION mask MASK_VALUE
1395 The watch command now supports the mask argument which allows creation
1396 of masked watchpoints, if the current architecture supports this feature.
1398 info auto-load-scripts [REGEXP]
1399 This command was formerly named "maintenance print section-scripts".
1400 It is now generally useful and is no longer a maintenance-only command.
1402 info macro [-all] [--] MACRO
1403 The info macro command has new options `-all' and `--'. The first for
1404 printing all definitions of a macro. The second for explicitly specifying
1405 the end of arguments and the beginning of the macro name in case the macro
1406 name starts with a hyphen.
1408 collect[/s] EXPRESSIONS
1409 The tracepoint collect command now takes an optional modifier "/s"
1410 that directs it to dereference pointer-to-character types and
1411 collect the bytes of memory up to a zero byte. The behavior is
1412 similar to what you see when you use the regular print command on a
1413 string. An optional integer following the "/s" sets a bound on the
1414 number of bytes that will be collected.
1417 The trace start command now interprets any supplied arguments as a
1418 note to be recorded with the trace run, with an effect similar to
1419 setting the variable trace-notes.
1422 The trace stop command now interprets any arguments as a note to be
1423 mentioned along with the tstatus report that the trace was stopped
1424 with a command. The effect is similar to setting the variable
1427 * Tracepoints can now be enabled and disabled at any time after a trace
1428 experiment has been started using the standard "enable" and "disable"
1429 commands. It is now possible to start a trace experiment with no enabled
1430 tracepoints; GDB will display a warning, but will allow the experiment to
1431 begin, assuming that tracepoints will be enabled as needed while the trace
1434 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1435 locations with 4-byte instructions, when they were previously
1436 limited to locations with instructions of 5 bytes or longer.
1440 set debug dwarf2-read
1441 show debug dwarf2-read
1442 Turns on or off display of debugging messages related to reading
1443 DWARF debug info. The default is off.
1445 set debug symtab-create
1446 show debug symtab-create
1447 Turns on or off display of debugging messages related to symbol table
1448 creation. The default is off.
1451 show extended-prompt
1452 Set the GDB prompt, and allow escape sequences to be inserted to
1453 display miscellaneous information (see 'help set extended-prompt'
1454 for the list of sequences). This prompt (and any information
1455 accessed through the escape sequences) is updated every time the
1456 prompt is displayed.
1458 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1459 show print entry-values
1460 Set printing of frame argument values at function entry. In some cases
1461 GDB can determine the value of function argument which was passed by the
1462 function caller, even if the value was modified inside the called function.
1464 set debug entry-values
1465 show debug entry-values
1466 Control display of debugging info for determining frame argument values at
1467 function entry and virtual tail call frames.
1469 set basenames-may-differ
1470 show basenames-may-differ
1471 Set whether a source file may have multiple base names.
1472 (A "base name" is the name of a file with the directory part removed.
1473 Example: The base name of "/home/user/hello.c" is "hello.c".)
1474 If set, GDB will canonicalize file names (e.g., expand symlinks)
1475 before comparing them. Canonicalization is an expensive operation,
1476 but it allows the same file be known by more than one base name.
1477 If not set (the default), all source files are assumed to have just
1478 one base name, and gdb will do file name comparisons more efficiently.
1484 Set a user name and notes for the current and any future trace runs.
1485 This is useful for long-running and/or disconnected traces, to
1486 inform others (or yourself) as to who is running the trace, supply
1487 contact information, or otherwise explain what is going on.
1489 set trace-stop-notes
1490 show trace-stop-notes
1491 Set a note attached to the trace run, that is displayed when the
1492 trace has been stopped by a tstop command. This is useful for
1493 instance as an explanation, if you are stopping a trace run that was
1494 started by someone else.
1496 * New remote packets
1500 Dynamically enable a tracepoint in a started trace experiment.
1504 Dynamically disable a tracepoint in a started trace experiment.
1508 Set the user and notes of the trace run.
1512 Query the current status of a tracepoint.
1516 Query the minimum length of instruction at which a fast tracepoint may
1519 * Dcache size (number of lines) and line-size are now runtime-configurable
1520 via "set dcache line" and "set dcache line-size" commands.
1524 Texas Instruments TMS320C6x tic6x-*-*
1528 Renesas RL78 rl78-*-elf
1530 *** Changes in GDB 7.3.1
1532 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1534 *** Changes in GDB 7.3
1536 * GDB has a new command: "thread find [REGEXP]".
1537 It finds the thread id whose name, target id, or thread extra info
1538 matches the given regular expression.
1540 * The "catch syscall" command now works on mips*-linux* targets.
1542 * The -data-disassemble MI command now supports modes 2 and 3 for
1543 dumping the instruction opcodes.
1545 * New command line options
1547 -data-directory DIR Specify DIR as the "data-directory".
1548 This is mostly for testing purposes.
1550 * The "maint set python auto-load on|off" command has been renamed to
1551 "set auto-load-scripts on|off".
1553 * GDB has a new command: "set directories".
1554 It is like the "dir" command except that it replaces the
1555 source path list instead of augmenting it.
1557 * GDB now understands thread names.
1559 On GNU/Linux, "info threads" will display the thread name as set by
1560 prctl or pthread_setname_np.
1562 There is also a new command, "thread name", which can be used to
1563 assign a name internally for GDB to display.
1566 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1567 has been integrated into GDB.
1571 ** The function gdb.Write now accepts an optional keyword 'stream'.
1572 This keyword, when provided, will direct the output to either
1573 stdout, stderr, or GDB's logging output.
1575 ** Parameters can now be be sub-classed in Python, and in particular
1576 you may implement the get_set_doc and get_show_doc functions.
1577 This improves how Parameter set/show documentation is processed
1578 and allows for more dynamic content.
1580 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1581 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1582 have an is_valid method.
1584 ** Breakpoints can now be sub-classed in Python, and in particular
1585 you may implement a 'stop' function that is executed each time
1586 the inferior reaches that breakpoint.
1588 ** New function gdb.lookup_global_symbol looks up a global symbol.
1590 ** GDB values in Python are now callable if the value represents a
1591 function. For example, if 'some_value' represents a function that
1592 takes two integer parameters and returns a value, you can call
1593 that function like so:
1595 result = some_value (10,20)
1597 ** Module gdb.types has been added.
1598 It contains a collection of utilities for working with gdb.Types objects:
1599 get_basic_type, has_field, make_enum_dict.
1601 ** Module gdb.printing has been added.
1602 It contains utilities for writing and registering pretty-printers.
1603 New classes: PrettyPrinter, SubPrettyPrinter,
1604 RegexpCollectionPrettyPrinter.
1605 New function: register_pretty_printer.
1607 ** New commands "info pretty-printers", "enable pretty-printer" and
1608 "disable pretty-printer" have been added.
1610 ** gdb.parameter("directories") is now available.
1612 ** New function gdb.newest_frame returns the newest frame in the
1615 ** The gdb.InferiorThread class has a new "name" attribute. This
1616 holds the thread's name.
1618 ** Python Support for Inferior events.
1619 Python scripts can add observers to be notified of events
1620 occurring in the process being debugged.
1621 The following events are currently supported:
1622 - gdb.events.cont Continue event.
1623 - gdb.events.exited Inferior exited event.
1624 - gdb.events.stop Signal received, and Breakpoint hit events.
1628 ** GDB now puts template parameters in scope when debugging in an
1629 instantiation. For example, if you have:
1631 template<int X> int func (void) { return X; }
1633 then if you step into func<5>, "print X" will show "5". This
1634 feature requires proper debuginfo support from the compiler; it
1635 was added to GCC 4.5.
1637 ** The motion commands "next", "finish", "until", and "advance" now
1638 work better when exceptions are thrown. In particular, GDB will
1639 no longer lose control of the inferior; instead, the GDB will
1640 stop the inferior at the point at which the exception is caught.
1641 This functionality requires a change in the exception handling
1642 code that was introduced in GCC 4.5.
1644 * GDB now follows GCC's rules on accessing volatile objects when
1645 reading or writing target state during expression evaluation.
1646 One notable difference to prior behavior is that "print x = 0"
1647 no longer generates a read of x; the value of the assignment is
1648 now always taken directly from the value being assigned.
1650 * GDB now has some support for using labels in the program's source in
1651 linespecs. For instance, you can use "advance label" to continue
1652 execution to a label.
1654 * GDB now has support for reading and writing a new .gdb_index
1655 section. This section holds a fast index of DWARF debugging
1656 information and can be used to greatly speed up GDB startup and
1657 operation. See the documentation for `save gdb-index' for details.
1659 * The "watch" command now accepts an optional "-location" argument.
1660 When used, this causes GDB to watch the memory referred to by the
1661 expression. Such a watchpoint is never deleted due to it going out
1664 * GDB now supports thread debugging of core dumps on GNU/Linux.
1666 GDB now activates thread debugging using the libthread_db library
1667 when debugging GNU/Linux core dumps, similarly to when debugging
1668 live processes. As a result, when debugging a core dump file, GDB
1669 is now able to display pthread_t ids of threads. For example, "info
1670 threads" shows the same output as when debugging the process when it
1671 was live. In earlier releases, you'd see something like this:
1674 * 1 LWP 6780 main () at main.c:10
1676 While now you see this:
1679 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1681 It is also now possible to inspect TLS variables when debugging core
1684 When debugging a core dump generated on a machine other than the one
1685 used to run GDB, you may need to point GDB at the correct
1686 libthread_db library with the "set libthread-db-search-path"
1687 command. See the user manual for more details on this command.
1689 * When natively debugging programs on PowerPC BookE processors running
1690 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1691 which stop execution of the inferior whenever it executes an instruction
1692 at any address within the specified range. See the "PowerPC Embedded"
1693 section in the user manual for more details.
1695 * New features in the GDB remote stub, GDBserver
1697 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1698 and i686 LynxOS (version 5.x).
1700 ** GDBserver is now supported on Blackfin Linux.
1702 * New native configurations
1704 ia64 HP-UX ia64-*-hpux*
1708 Analog Devices, Inc. Blackfin Processor bfin-*
1710 * Ada task switching is now supported on sparc-elf targets when
1711 debugging a program using the Ravenscar Profile. For more information,
1712 see the "Tasking Support when using the Ravenscar Profile" section
1713 in the GDB user manual.
1715 * Guile support was removed.
1717 * New features in the GNU simulator
1719 ** The --map-info flag lists all known core mappings.
1721 ** CFI flashes may be simulated via the "cfi" device.
1723 *** Changes in GDB 7.2
1725 * Shared library support for remote targets by default
1727 When GDB is configured for a generic, non-OS specific target, like
1728 for example, --target=arm-eabi or one of the many *-*-elf targets,
1729 GDB now queries remote stubs for loaded shared libraries using the
1730 `qXfer:libraries:read' packet. Previously, shared library support
1731 was always disabled for such configurations.
1735 ** Argument Dependent Lookup (ADL)
1737 In C++ ADL lookup directs function search to the namespaces of its
1738 arguments even if the namespace has not been imported.
1748 Here the compiler will search for `foo' in the namespace of 'b'
1749 and find A::foo. GDB now supports this. This construct is commonly
1750 used in the Standard Template Library for operators.
1752 ** Improved User Defined Operator Support
1754 In addition to member operators, GDB now supports lookup of operators
1755 defined in a namespace and imported with a `using' directive, operators
1756 defined in the global scope, operators imported implicitly from an
1757 anonymous namespace, and the ADL operators mentioned in the previous
1759 GDB now also supports proper overload resolution for all the previously
1760 mentioned flavors of operators.
1762 ** static const class members
1764 Printing of static const class members that are initialized in the
1765 class definition has been fixed.
1767 * Windows Thread Information Block access.
1769 On Windows targets, GDB now supports displaying the Windows Thread
1770 Information Block (TIB) structure. This structure is visible either
1771 by using the new command `info w32 thread-information-block' or, by
1772 dereferencing the new convenience variable named `$_tlb', a
1773 thread-specific pointer to the TIB. This feature is also supported
1774 when remote debugging using GDBserver.
1776 * Static tracepoints
1778 Static tracepoints are calls in the user program into a tracing
1779 library. One such library is a port of the LTTng kernel tracer to
1780 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1781 When debugging with GDBserver, GDB now supports combining the GDB
1782 tracepoint machinery with such libraries. For example: the user can
1783 use GDB to probe a static tracepoint marker (a call from the user
1784 program into the tracing library) with the new "strace" command (see
1785 "New commands" below). This creates a "static tracepoint" in the
1786 breakpoint list, that can be manipulated with the same feature set
1787 as fast and regular tracepoints. E.g., collect registers, local and
1788 global variables, collect trace state variables, and define
1789 tracepoint conditions. In addition, the user can collect extra
1790 static tracepoint marker specific data, by collecting the new
1791 $_sdata internal variable. When analyzing the trace buffer, you can
1792 inspect $_sdata like any other variable available to GDB. For more
1793 information, see the "Tracepoints" chapter in GDB user manual. New
1794 remote packets have been defined to support static tracepoints, see
1795 the "New remote packets" section below.
1797 * Better reconstruction of tracepoints after disconnected tracing
1799 GDB will attempt to download the original source form of tracepoint
1800 definitions when starting a trace run, and then will upload these
1801 upon reconnection to the target, resulting in a more accurate
1802 reconstruction of the tracepoints that are in use on the target.
1806 You can now exercise direct control over the ways that GDB can
1807 affect your program. For instance, you can disallow the setting of
1808 breakpoints, so that the program can run continuously (assuming
1809 non-stop mode). In addition, the "observer" variable is available
1810 to switch all of the different controls; in observer mode, GDB
1811 cannot affect the target's behavior at all, which is useful for
1812 tasks like diagnosing live systems in the field.
1814 * The new convenience variable $_thread holds the number of the
1817 * New remote packets
1821 Return the address of the Windows Thread Information Block of a given thread.
1825 In response to several of the tracepoint packets, the target may now
1826 also respond with a number of intermediate `qRelocInsn' request
1827 packets before the final result packet, to have GDB handle
1828 relocating an instruction to execute at a different address. This
1829 is particularly useful for stubs that support fast tracepoints. GDB
1830 reports support for this feature in the qSupported packet.
1834 List static tracepoint markers in the target program.
1838 List static tracepoint markers at a given address in the target
1841 qXfer:statictrace:read
1843 Read the static trace data collected (by a `collect $_sdata'
1844 tracepoint action). The remote stub reports support for this packet
1845 to gdb's qSupported query.
1849 Send the current settings of GDB's permission flags.
1853 Send part of the source (textual) form of a tracepoint definition,
1854 which includes location, conditional, and action list.
1856 * The source command now accepts a -s option to force searching for the
1857 script in the source search path even if the script name specifies
1860 * New features in the GDB remote stub, GDBserver
1862 - GDBserver now support tracepoints (including fast tracepoints, and
1863 static tracepoints). The feature is currently supported by the
1864 i386-linux and amd64-linux builds. See the "Tracepoints support
1865 in gdbserver" section in the manual for more information.
1867 GDBserver JIT compiles the tracepoint's conditional agent
1868 expression bytecode into native code whenever possible for low
1869 overhead dynamic tracepoints conditionals. For such tracepoints,
1870 an expression that examines program state is evaluated when the
1871 tracepoint is reached, in order to determine whether to capture
1872 trace data. If the condition is simple and false, processing the
1873 tracepoint finishes very quickly and no data is gathered.
1875 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1876 for static tracepoints support.
1878 - GDBserver now supports x86_64 Windows 64-bit debugging.
1880 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1881 it understands register description.
1883 * The --batch flag now disables pagination and queries.
1885 * X86 general purpose registers
1887 GDB now supports reading/writing byte, word and double-word x86
1888 general purpose registers directly. This means you can use, say,
1889 $ah or $ax to refer, respectively, to the byte register AH and
1890 16-bit word register AX that are actually portions of the 32-bit
1891 register EAX or 64-bit register RAX.
1893 * The `commands' command now accepts a range of breakpoints to modify.
1894 A plain `commands' following a command that creates multiple
1895 breakpoints affects all the breakpoints set by that command. This
1896 applies to breakpoints set by `rbreak', and also applies when a
1897 single `break' command creates multiple breakpoints (e.g.,
1898 breakpoints on overloaded c++ functions).
1900 * The `rbreak' command now accepts a filename specification as part of
1901 its argument, limiting the functions selected by the regex to those
1902 in the specified file.
1904 * Support for remote debugging Windows and SymbianOS shared libraries
1905 from Unix hosts has been improved. Non Windows GDB builds now can
1906 understand target reported file names that follow MS-DOS based file
1907 system semantics, such as file names that include drive letters and
1908 use the backslash character as directory separator. This makes it
1909 possible to transparently use the "set sysroot" and "set
1910 solib-search-path" on Unix hosts to point as host copies of the
1911 target's shared libraries. See the new command "set
1912 target-file-system-kind" described below, and the "Commands to
1913 specify files" section in the user manual for more information.
1917 eval template, expressions...
1918 Convert the values of one or more expressions under the control
1919 of the string template to a command line, and call it.
1921 set target-file-system-kind unix|dos-based|auto
1922 show target-file-system-kind
1923 Set or show the assumed file system kind for target reported file
1926 save breakpoints <filename>
1927 Save all current breakpoint definitions to a file suitable for use
1928 in a later debugging session. To read the saved breakpoint
1929 definitions, use the `source' command.
1931 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1934 info static-tracepoint-markers
1935 Display information about static tracepoint markers in the target.
1937 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1938 Define a static tracepoint by probing a marker at the given
1939 function, line, address, or marker ID.
1943 Enable and disable observer mode.
1945 set may-write-registers on|off
1946 set may-write-memory on|off
1947 set may-insert-breakpoints on|off
1948 set may-insert-tracepoints on|off
1949 set may-insert-fast-tracepoints on|off
1950 set may-interrupt on|off
1951 Set individual permissions for GDB effects on the target. Note that
1952 some of these settings can have undesirable or surprising
1953 consequences, particularly when changed in the middle of a session.
1954 For instance, disabling the writing of memory can prevent
1955 breakpoints from being inserted, cause single-stepping to fail, or
1956 even crash your program, if you disable after breakpoints have been
1957 inserted. However, GDB should not crash.
1959 set record memory-query on|off
1960 show record memory-query
1961 Control whether to stop the inferior if memory changes caused
1962 by an instruction cannot be recorded.
1967 The disassemble command now supports "start,+length" form of two arguments.
1971 ** GDB now provides a new directory location, called the python directory,
1972 where Python scripts written for GDB can be installed. The location
1973 of that directory is <data-directory>/python, where <data-directory>
1974 is the GDB data directory. For more details, see section `Scripting
1975 GDB using Python' in the manual.
1977 ** The GDB Python API now has access to breakpoints, symbols, symbol
1978 tables, program spaces, inferiors, threads and frame's code blocks.
1979 Additionally, GDB Parameters can now be created from the API, and
1980 manipulated via set/show in the CLI.
1982 ** New functions gdb.target_charset, gdb.target_wide_charset,
1983 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1985 ** New exception gdb.GdbError.
1987 ** Pretty-printers are now also looked up in the current program space.
1989 ** Pretty-printers can now be individually enabled and disabled.
1991 ** GDB now looks for names of Python scripts to auto-load in a
1992 special section named `.debug_gdb_scripts', in addition to looking
1993 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1995 * Tracepoint actions were unified with breakpoint commands. In particular,
1996 there are no longer differences in "info break" output for breakpoints and
1997 tracepoints and the "commands" command can be used for both tracepoints and
1998 regular breakpoints.
2002 ARM Symbian arm*-*-symbianelf*
2004 * D language support.
2005 GDB now supports debugging programs written in the D programming
2008 * GDB now supports the extended ptrace interface for PowerPC which is
2009 available since Linux kernel version 2.6.34. This automatically enables
2010 any hardware breakpoints and additional hardware watchpoints available in
2011 the processor. The old ptrace interface exposes just one hardware
2012 watchpoint and no hardware breakpoints.
2014 * GDB is now able to use the Data Value Compare (DVC) register available on
2015 embedded PowerPC processors to implement in hardware simple watchpoint
2016 conditions of the form:
2018 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2020 This works in native GDB running on Linux kernels with the extended ptrace
2021 interface mentioned above.
2023 *** Changes in GDB 7.1
2027 ** Namespace Support
2029 GDB now supports importing of namespaces in C++. This enables the
2030 user to inspect variables from imported namespaces. Support for
2031 namepace aliasing has also been added. So, if a namespace is
2032 aliased in the current scope (e.g. namepace C=A; ) the user can
2033 print variables using the alias (e.g. (gdb) print C::x).
2037 All known bugs relating to the printing of virtual base class were
2038 fixed. It is now possible to call overloaded static methods using a
2043 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2044 and reinterpret_cast<> are now handled by the C++ expression parser.
2048 Xilinx MicroBlaze microblaze-*-*
2053 Xilinx MicroBlaze microblaze
2056 * Multi-program debugging.
2058 GDB now has support for multi-program (a.k.a. multi-executable or
2059 multi-exec) debugging. This allows for debugging multiple inferiors
2060 simultaneously each running a different program under the same GDB
2061 session. See "Debugging Multiple Inferiors and Programs" in the
2062 manual for more information. This implied some user visible changes
2063 in the multi-inferior support. For example, "info inferiors" now
2064 lists inferiors that are not running yet or that have exited
2065 already. See also "New commands" and "New options" below.
2067 * New tracing features
2069 GDB's tracepoint facility now includes several new features:
2071 ** Trace state variables
2073 GDB tracepoints now include support for trace state variables, which
2074 are variables managed by the target agent during a tracing
2075 experiment. They are useful for tracepoints that trigger each
2076 other, so for instance one tracepoint can count hits in a variable,
2077 and then a second tracepoint has a condition that is true when the
2078 count reaches a particular value. Trace state variables share the
2079 $-syntax of GDB convenience variables, and can appear in both
2080 tracepoint actions and condition expressions. Use the "tvariable"
2081 command to create, and "info tvariables" to view; see "Trace State
2082 Variables" in the manual for more detail.
2086 GDB now includes an option for defining fast tracepoints, which
2087 targets may implement more efficiently, such as by installing a jump
2088 into the target agent rather than a trap instruction. The resulting
2089 speedup can be by two orders of magnitude or more, although the
2090 tradeoff is that some program locations on some target architectures
2091 might not allow fast tracepoint installation, for instance if the
2092 instruction to be replaced is shorter than the jump. To request a
2093 fast tracepoint, use the "ftrace" command, with syntax identical to
2094 the regular trace command.
2096 ** Disconnected tracing
2098 It is now possible to detach GDB from the target while it is running
2099 a trace experiment, then reconnect later to see how the experiment
2100 is going. In addition, a new variable disconnected-tracing lets you
2101 tell the target agent whether to continue running a trace if the
2102 connection is lost unexpectedly.
2106 GDB now has the ability to save the trace buffer into a file, and
2107 then use that file as a target, similarly to you can do with
2108 corefiles. You can select trace frames, print data that was
2109 collected in them, and use tstatus to display the state of the
2110 tracing run at the moment that it was saved. To create a trace
2111 file, use "tsave <filename>", and to use it, do "target tfile
2114 ** Circular trace buffer
2116 You can ask the target agent to handle the trace buffer as a
2117 circular buffer, discarding the oldest trace frames to make room for
2118 newer ones, by setting circular-trace-buffer to on. This feature may
2119 not be available for all target agents.
2124 The disassemble command, when invoked with two arguments, now requires
2125 the arguments to be comma-separated.
2128 The info variables command now displays variable definitions. Files
2129 which only declare a variable are not shown.
2132 The source command is now capable of sourcing Python scripts.
2133 This feature is dependent on the debugger being build with Python
2136 Related to this enhancement is also the introduction of a new command
2137 "set script-extension" (see below).
2139 * New commands (for set/show, see "New options" below)
2141 record save [<FILENAME>]
2142 Save a file (in core file format) containing the process record
2143 execution log for replay debugging at a later time.
2145 record restore <FILENAME>
2146 Restore the process record execution log that was saved at an
2147 earlier time, for replay debugging.
2149 add-inferior [-copies <N>] [-exec <FILENAME>]
2152 clone-inferior [-copies <N>] [ID]
2153 Make a new inferior ready to execute the same program another
2154 inferior has loaded.
2159 maint info program-spaces
2160 List the program spaces loaded into GDB.
2162 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2163 show remote interrupt-sequence
2164 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2165 as the sequence to the remote target in order to interrupt the execution.
2166 Ctrl-C is a default. Some system prefers BREAK which is high level of
2167 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2168 Magic SysRq g. It is BREAK signal and character 'g'.
2170 set remote interrupt-on-connect [on | off]
2171 show remote interrupt-on-connect
2172 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2173 remote target when gdb connects to it. This is needed when you debug
2176 set remotebreak [on | off]
2178 Deprecated. Use "set/show remote interrupt-sequence" instead.
2180 tvariable $NAME [ = EXP ]
2181 Create or modify a trace state variable.
2184 List trace state variables and their values.
2186 delete tvariable $NAME ...
2187 Delete one or more trace state variables.
2190 Evaluate the given expressions without collecting anything into the
2191 trace buffer. (Valid in tracepoint actions only.)
2193 ftrace FN / FILE:LINE / *ADDR
2194 Define a fast tracepoint at the given function, line, or address.
2196 * New expression syntax
2198 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2199 GDB now parses 0b101010 identically with 42.
2203 set follow-exec-mode new|same
2204 show follow-exec-mode
2205 Control whether GDB reuses the same inferior across an exec call or
2206 creates a new one. This is useful to be able to restart the old
2207 executable after the inferior having done an exec call.
2209 set default-collect EXPR, ...
2210 show default-collect
2211 Define a list of expressions to be collected at each tracepoint.
2212 This is a useful way to ensure essential items are not overlooked,
2213 such as registers or a critical global variable.
2215 set disconnected-tracing
2216 show disconnected-tracing
2217 If set to 1, the target is instructed to continue tracing if it
2218 loses its connection to GDB. If 0, the target is to stop tracing
2221 set circular-trace-buffer
2222 show circular-trace-buffer
2223 If set to on, the target is instructed to use a circular trace buffer
2224 and discard the oldest trace frames instead of stopping the trace due
2225 to a full trace buffer. If set to off, the trace stops when the buffer
2226 fills up. Some targets may not support this.
2228 set script-extension off|soft|strict
2229 show script-extension
2230 If set to "off", the debugger does not perform any script language
2231 recognition, and all sourced files are assumed to be GDB scripts.
2232 If set to "soft" (the default), files are sourced according to
2233 filename extension, falling back to GDB scripts if the first
2235 If set to "strict", files are sourced according to filename extension.
2237 set ada trust-PAD-over-XVS on|off
2238 show ada trust-PAD-over-XVS
2239 If off, activate a workaround against a bug in the debugging information
2240 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2241 the GCC sources for more information about the GNAT encoding and
2242 PAD types in particular). It is always safe to set this option to
2243 off, but this introduces a slight performance penalty. The default
2246 * Python API Improvements
2248 ** GDB provides the new class gdb.LazyString. This is useful in
2249 some pretty-printing cases. The new method gdb.Value.lazy_string
2250 provides a simple way to create objects of this type.
2252 ** The fields returned by gdb.Type.fields now have an
2253 `is_base_class' attribute.
2255 ** The new method gdb.Type.range returns the range of an array type.
2257 ** The new method gdb.parse_and_eval can be used to parse and
2258 evaluate an expression.
2260 * New remote packets
2263 Define a trace state variable.
2266 Get the current value of a trace state variable.
2269 Set desired tracing behavior upon disconnection.
2272 Set the trace buffer to be linear or circular.
2275 Get data about the tracepoints currently in use.
2279 Process record now works correctly with hardware watchpoints.
2281 Multiple bug fixes have been made to the mips-irix port, making it
2282 much more reliable. In particular:
2283 - Debugging threaded applications is now possible again. Previously,
2284 GDB would hang while starting the program, or while waiting for
2285 the program to stop at a breakpoint.
2286 - Attaching to a running process no longer hangs.
2287 - An error occurring while loading a core file has been fixed.
2288 - Changing the value of the PC register now works again. This fixes
2289 problems observed when using the "jump" command, or when calling
2290 a function from GDB, or even when assigning a new value to $pc.
2291 - With the "finish" and "return" commands, the return value for functions
2292 returning a small array is now correctly printed.
2293 - It is now possible to break on shared library code which gets executed
2294 during a shared library init phase (code executed while executing
2295 their .init section). Previously, the breakpoint would have no effect.
2296 - GDB is now able to backtrace through the signal handler for
2297 non-threaded programs.
2299 PIE (Position Independent Executable) programs debugging is now supported.
2300 This includes debugging execution of PIC (Position Independent Code) shared
2301 libraries although for that, it should be possible to run such libraries as an
2304 *** Changes in GDB 7.0
2306 * GDB now has an interface for JIT compilation. Applications that
2307 dynamically generate code can create symbol files in memory and register
2308 them with GDB. For users, the feature should work transparently, and
2309 for JIT developers, the interface is documented in the GDB manual in the
2310 "JIT Compilation Interface" chapter.
2312 * Tracepoints may now be conditional. The syntax is as for
2313 breakpoints; either an "if" clause appended to the "trace" command,
2314 or the "condition" command is available. GDB sends the condition to
2315 the target for evaluation using the same bytecode format as is used
2316 for tracepoint actions.
2318 * The disassemble command now supports: an optional /r modifier, print the
2319 raw instructions in hex as well as in symbolic form, and an optional /m
2320 modifier to print mixed source+assembly.
2322 * Process record and replay
2324 In a architecture environment that supports ``process record and
2325 replay'', ``process record and replay'' target can record a log of
2326 the process execution, and replay it with both forward and reverse
2329 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2330 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2331 set execution-direction {forward|reverse}, for targets that support
2334 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2335 feature is available with a native GDB running on kernel version
2338 * GDB now has support for multi-byte and wide character sets on the
2339 target. Strings whose character type is wchar_t, char16_t, or
2340 char32_t are now correctly printed. GDB supports wide- and unicode-
2341 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2342 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2343 `printf'. This feature requires iconv to work properly; if your
2344 system does not have a working iconv, GDB can use GNU libiconv. See
2345 the installation instructions for more information.
2347 * GDB now supports automatic retrieval of shared library files from
2348 remote targets. To use this feature, specify a system root that begins
2349 with the `remote:' prefix, either via the `set sysroot' command or via
2350 the `--with-sysroot' configure-time option.
2352 * "info sharedlibrary" now takes an optional regex of libraries to show,
2353 and it now reports if a shared library has no debugging information.
2355 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2356 now complete on file names.
2358 * When completing in expressions, gdb will attempt to limit
2359 completions to allowable structure or union fields, where appropriate.
2360 For instance, consider:
2362 # struct example { int f1; double f2; };
2363 # struct example variable;
2366 If the user types TAB at the end of this command line, the available
2367 completions will be "f1" and "f2".
2369 * Inlined functions are now supported. They show up in backtraces, and
2370 the "step", "next", and "finish" commands handle them automatically.
2372 * GDB now supports the token-splicing (##) and stringification (#)
2373 operators when expanding macros. It also supports variable-arity
2376 * GDB now supports inspecting extra signal information, exported by
2377 the new $_siginfo convenience variable. The feature is currently
2378 implemented on linux ARM, i386 and amd64.
2380 * GDB can now display the VFP floating point registers and NEON vector
2381 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2382 can provide these registers (requires Linux 2.6.30 or later). Remote
2383 and simulator targets may also provide them.
2385 * New remote packets
2388 Search memory for a sequence of bytes.
2391 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2392 operation over reliable transport links. Use of this packet is
2393 controlled by the `set remote noack-packet' command.
2396 Kill the process with the specified process ID. Use this in preference
2397 to `k' when multiprocess protocol extensions are supported.
2400 Obtains additional operating system information
2404 Read or write additional signal information.
2406 * Removed remote protocol undocumented extension
2408 An undocumented extension to the remote protocol's `S' stop reply
2409 packet that permited the stub to pass a process id was removed.
2410 Remote servers should use the `T' stop reply packet instead.
2412 * GDB now supports multiple function calling conventions according to the
2413 DWARF-2 DW_AT_calling_convention function attribute.
2415 * The SH target utilizes the aforementioned change to distinguish between gcc
2416 and Renesas calling convention. It also adds the new CLI commands
2417 `set/show sh calling-convention'.
2419 * GDB can now read compressed debug sections, as produced by GNU gold
2420 with the --compress-debug-sections=zlib flag.
2422 * 64-bit core files are now supported on AIX.
2424 * Thread switching is now supported on Tru64.
2426 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2427 which will be allocated using malloc later in program execution.
2429 * The qXfer:libraries:read remote procotol packet now allows passing a
2430 list of section offsets.
2432 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2433 conditions handling signals delivered during attach or thread creation
2434 have also been fixed.
2436 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2437 From the user's standpoint, all unqualified instances of True and False
2438 are treated as the standard definitions, regardless of context.
2440 * GDB now parses C++ symbol and type names more flexibly. For
2443 template<typename T> class C { };
2446 GDB will now correctly handle all of:
2448 ptype C<char const *>
2449 ptype C<char const*>
2450 ptype C<const char *>
2451 ptype C<const char*>
2453 * New features in the GDB remote stub, gdbserver
2455 - The "--wrapper" command-line argument tells gdbserver to use a
2456 wrapper program to launch programs for debugging.
2458 - On PowerPC and S/390 targets, it is now possible to use a single
2459 gdbserver executable to debug both 32-bit and 64-bit programs.
2460 (This requires gdbserver itself to be built as a 64-bit executable.)
2462 - gdbserver uses the new noack protocol mode for TCP connections to
2463 reduce communications latency, if also supported and enabled in GDB.
2465 - Support for the sparc64-linux-gnu target is now included in
2468 - The amd64-linux build of gdbserver now supports debugging both
2469 32-bit and 64-bit programs.
2471 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2472 now support hardware watchpoints, and will use them automatically
2477 GDB now has support for scripting using Python. Whether this is
2478 available is determined at configure time.
2480 New GDB commands can now be written in Python.
2482 * Ada tasking support
2484 Ada tasks can now be inspected in GDB. The following commands have
2488 Print the list of Ada tasks.
2490 Print detailed information about task number N.
2492 Print the task number of the current task.
2494 Switch the context of debugging to task number N.
2496 * Support for user-defined prefixed commands. The "define" command can
2497 add new commands to existing prefixes, e.g. "target".
2499 * Multi-inferior, multi-process debugging.
2501 GDB now has generalized support for multi-inferior debugging. See
2502 "Debugging Multiple Inferiors" in the manual for more information.
2503 Although availability still depends on target support, the command
2504 set is more uniform now. The GNU/Linux specific multi-forks support
2505 has been migrated to this new framework. This implied some user
2506 visible changes; see "New commands" and also "Removed commands"
2509 * Target descriptions can now describe the target OS ABI. See the
2510 "Target Description Format" section in the user manual for more
2513 * Target descriptions can now describe "compatible" architectures
2514 to indicate that the target can execute applications for a different
2515 architecture in addition to those for the main target architecture.
2516 See the "Target Description Format" section in the user manual for
2519 * Multi-architecture debugging.
2521 GDB now includes general supports for debugging applications on
2522 hybrid systems that use more than one single processor architecture
2523 at the same time. Each such hybrid architecture still requires
2524 specific support to be added. The only hybrid architecture supported
2525 in this version of GDB is the Cell Broadband Engine.
2527 * GDB now supports integrated debugging of Cell/B.E. applications that
2528 use both the PPU and SPU architectures. To enable support for hybrid
2529 Cell/B.E. debugging, you need to configure GDB to support both the
2530 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2531 --enable-targets configure option.
2533 * Non-stop mode debugging.
2535 For some targets, GDB now supports an optional mode of operation in
2536 which you can examine stopped threads while other threads continue
2537 to execute freely. This is referred to as non-stop mode, with the
2538 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2539 section in the user manual for more information.
2541 To be able to support remote non-stop debugging, a remote stub needs
2542 to implement the non-stop mode remote protocol extensions, as
2543 described in the "Remote Non-Stop" section of the user manual. The
2544 GDB remote stub, gdbserver, has been adjusted to support these
2545 extensions on linux targets.
2547 * New commands (for set/show, see "New options" below)
2549 catch syscall [NAME(S) | NUMBER(S)]
2550 Catch system calls. Arguments, which should be names of system
2551 calls or their numbers, mean catch only those syscalls. Without
2552 arguments, every syscall will be caught. When the inferior issues
2553 any of the specified syscalls, GDB will stop and announce the system
2554 call, both when it is called and when its call returns. This
2555 feature is currently available with a native GDB running on the
2556 Linux Kernel, under the following architectures: x86, x86_64,
2557 PowerPC and PowerPC64.
2559 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2561 Search memory for a sequence of bytes.
2563 maint set python print-stack
2564 maint show python print-stack
2565 Show a stack trace when an error is encountered in a Python script.
2568 Invoke CODE by passing it to the Python interpreter.
2573 These allow macros to be defined, undefined, and listed
2577 Show operating system information about processes.
2580 List the inferiors currently under GDB's control.
2583 Switch focus to inferior number NUM.
2586 Detach from inferior number NUM.
2589 Kill inferior number NUM.
2593 set spu stop-on-load
2594 show spu stop-on-load
2595 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2597 set spu auto-flush-cache
2598 show spu auto-flush-cache
2599 Control whether to automatically flush the software-managed cache
2600 during Cell/B.E. debugging.
2602 set sh calling-convention
2603 show sh calling-convention
2604 Control the calling convention used when calling SH target functions.
2607 show debug timestamp
2608 Control display of timestamps with GDB debugging output.
2610 set disassemble-next-line
2611 show disassemble-next-line
2612 Control display of disassembled source lines or instructions when
2615 set remote noack-packet
2616 show remote noack-packet
2617 Set/show the use of remote protocol QStartNoAckMode packet. See above
2618 under "New remote packets."
2620 set remote query-attached-packet
2621 show remote query-attached-packet
2622 Control use of remote protocol `qAttached' (query-attached) packet.
2624 set remote read-siginfo-object
2625 show remote read-siginfo-object
2626 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2629 set remote write-siginfo-object
2630 show remote write-siginfo-object
2631 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2634 set remote reverse-continue
2635 show remote reverse-continue
2636 Control use of remote protocol 'bc' (reverse-continue) packet.
2638 set remote reverse-step
2639 show remote reverse-step
2640 Control use of remote protocol 'bs' (reverse-step) packet.
2642 set displaced-stepping
2643 show displaced-stepping
2644 Control displaced stepping mode. Displaced stepping is a way to
2645 single-step over breakpoints without removing them from the debuggee.
2646 Also known as "out-of-line single-stepping".
2649 show debug displaced
2650 Control display of debugging info for displaced stepping.
2652 maint set internal-error
2653 maint show internal-error
2654 Control what GDB does when an internal error is detected.
2656 maint set internal-warning
2657 maint show internal-warning
2658 Control what GDB does when an internal warning is detected.
2663 Use a wrapper program to launch programs for debugging.
2665 set multiple-symbols (all|ask|cancel)
2666 show multiple-symbols
2667 The value of this variable can be changed to adjust the debugger behavior
2668 when an expression or a breakpoint location contains an ambiguous symbol
2669 name (an overloaded function name, for instance).
2671 set breakpoint always-inserted
2672 show breakpoint always-inserted
2673 Keep breakpoints always inserted in the target, as opposed to inserting
2674 them when resuming the target, and removing them when the target stops.
2675 This option can improve debugger performance on slow remote targets.
2677 set arm fallback-mode (arm|thumb|auto)
2678 show arm fallback-mode
2679 set arm force-mode (arm|thumb|auto)
2681 These commands control how ARM GDB determines whether instructions
2682 are ARM or Thumb. The default for both settings is auto, which uses
2683 the current CPSR value for instructions without symbols; previous
2684 versions of GDB behaved as if "set arm fallback-mode arm".
2686 set disable-randomization
2687 show disable-randomization
2688 Standalone programs run with the virtual address space randomization enabled
2689 by default on some platforms. This option keeps the addresses stable across
2690 multiple debugging sessions.
2694 Control whether other threads are stopped or not when some thread hits
2699 Requests that asynchronous execution is enabled in the target, if available.
2700 In this case, it's possible to resume target in the background, and interact
2701 with GDB while the target is running. "show target-async" displays the
2702 current state of asynchronous execution of the target.
2704 set target-wide-charset
2705 show target-wide-charset
2706 The target-wide-charset is the name of the character set that GDB
2707 uses when printing characters whose type is wchar_t.
2709 set tcp auto-retry (on|off)
2711 set tcp connect-timeout
2712 show tcp connect-timeout
2713 These commands allow GDB to retry failed TCP connections to a remote stub
2714 with a specified timeout period; this is useful if the stub is launched
2715 in parallel with GDB but may not be ready to accept connections immediately.
2717 set libthread-db-search-path
2718 show libthread-db-search-path
2719 Control list of directories which GDB will search for appropriate
2722 set schedule-multiple (on|off)
2723 show schedule-multiple
2724 Allow GDB to resume all threads of all processes or only threads of
2725 the current process.
2729 Use more aggressive caching for accesses to the stack. This improves
2730 performance of remote debugging (particularly backtraces) without
2731 affecting correctness.
2733 set interactive-mode (on|off|auto)
2734 show interactive-mode
2735 Control whether GDB runs in interactive mode (on) or not (off).
2736 When in interactive mode, GDB waits for the user to answer all
2737 queries. Otherwise, GDB does not wait and assumes the default
2738 answer. When set to auto (the default), GDB determines which
2739 mode to use based on the stdin settings.
2744 For program forks, this is replaced by the new more generic `info
2745 inferiors' command. To list checkpoints, you can still use the
2746 `info checkpoints' command, which was an alias for the `info forks'
2750 Replaced by the new `inferior' command. To switch between
2751 checkpoints, you can still use the `restart' command, which was an
2752 alias for the `fork' command.
2755 This is removed, since some targets don't have a notion of
2756 processes. To switch between processes, you can still use the
2757 `inferior' command using GDB's own inferior number.
2760 For program forks, this is replaced by the new more generic `kill
2761 inferior' command. To delete a checkpoint, you can still use the
2762 `delete checkpoint' command, which was an alias for the `delete
2766 For program forks, this is replaced by the new more generic `detach
2767 inferior' command. To detach a checkpoint, you can still use the
2768 `detach checkpoint' command, which was an alias for the `detach
2771 * New native configurations
2773 x86/x86_64 Darwin i[34567]86-*-darwin*
2775 x86_64 MinGW x86_64-*-mingw*
2779 Lattice Mico32 lm32-*
2780 x86 DICOS i[34567]86-*-dicos*
2781 x86_64 DICOS x86_64-*-dicos*
2784 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2785 (mingw32ce) debugging.
2791 These commands were actually not implemented on any target.
2793 *** Changes in GDB 6.8
2795 * New native configurations
2797 NetBSD/hppa hppa*-*netbsd*
2798 Xtensa GNU/Linux xtensa*-*-linux*
2802 NetBSD/hppa hppa*-*-netbsd*
2803 Xtensa GNU/Lunux xtensa*-*-linux*
2805 * Change in command line behavior -- corefiles vs. process ids.
2807 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2808 attaching to process NUMBER fails, GDB no longer attempts to open a
2809 core file named NUMBER. Attaching to a program using the -c option
2810 is no longer supported. Instead, use the '-p' or '--pid' options.
2812 * GDB can now be built as a native debugger for debugging Windows x86
2813 (mingw32) Portable Executable (PE) programs.
2815 * Pending breakpoints no longer change their number when their address
2818 * GDB now supports breakpoints with multiple locations,
2819 including breakpoints on C++ constructors, inside C++ templates,
2820 and in inlined functions.
2822 * GDB's ability to debug optimized code has been improved. GDB more
2823 accurately identifies function bodies and lexical blocks that occupy
2824 more than one contiguous range of addresses.
2826 * Target descriptions can now describe registers for PowerPC.
2828 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2829 registers on PowerPC targets.
2831 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2832 targets even when the libthread_db library is not available.
2834 * The GDB remote stub, gdbserver, now supports the new file transfer
2835 commands (remote put, remote get, and remote delete).
2837 * The GDB remote stub, gdbserver, now supports run and attach in
2838 extended-remote mode.
2840 * hppa*64*-*-hpux11* target broken
2841 The debugger is unable to start a program and fails with the following
2842 error: "Error trying to get information about dynamic linker".
2843 The gdb-6.7 release is also affected.
2845 * GDB now supports the --enable-targets= configure option to allow
2846 building a single GDB executable that supports multiple remote
2847 target architectures.
2849 * GDB now supports debugging C and C++ programs which use the
2850 Decimal Floating Point extension. In addition, the PowerPC target
2851 now has a set of pseudo-registers to inspect decimal float values
2852 stored in two consecutive float registers.
2854 * The -break-insert MI command can optionally create pending
2857 * Improved support for debugging Ada
2858 Many improvements to the Ada language support have been made. These
2860 - Better support for Ada2005 interface types
2861 - Improved handling of arrays and slices in general
2862 - Better support for Taft-amendment types
2863 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2865 - Improved command completion in Ada
2868 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2873 set print frame-arguments (all|scalars|none)
2874 show print frame-arguments
2875 The value of this variable can be changed to control which argument
2876 values should be printed by the debugger when displaying a frame.
2881 Transfer files to and from a remote target, and delete remote files.
2888 Transfer files to and from a remote target, and delete remote files.
2890 * New remote packets
2897 Open, close, read, write, and delete files on the remote system.
2900 Attach to an existing process on the remote system, in extended-remote
2904 Run a new process on the remote system, in extended-remote mode.
2906 *** Changes in GDB 6.7
2908 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2909 bfd, libiberty and opcodes, as revealed by static analysis donated by
2910 Coverity, Inc. (http://scan.coverity.com).
2912 * When looking up multiply-defined global symbols, GDB will now prefer the
2913 symbol definition in the current shared library if it was built using the
2914 -Bsymbolic linker option.
2916 * When the Text User Interface (TUI) is not configured, GDB will now
2917 recognize the -tui command-line option and print a message that the TUI
2920 * The GDB remote stub, gdbserver, now has lower overhead for high
2921 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2923 * GDB for MIPS targets now autodetects whether a remote target provides
2924 32-bit or 64-bit register values.
2926 * Support for C++ member pointers has been improved.
2928 * GDB now understands XML target descriptions, which specify the
2929 target's overall architecture. GDB can read a description from
2930 a local file or over the remote serial protocol.
2932 * Vectors of single-byte data use a new integer type which is not
2933 automatically displayed as character or string data.
2935 * The /s format now works with the print command. It displays
2936 arrays of single-byte integers and pointers to single-byte integers
2939 * Target descriptions can now describe target-specific registers,
2940 for architectures which have implemented the support (currently
2941 only ARM, M68K, and MIPS).
2943 * GDB and the GDB remote stub, gdbserver, now support the XScale
2946 * The GDB remote stub, gdbserver, has been updated to support
2947 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2948 has been rewritten to use the standard GDB remote protocol.
2950 * GDB can now step into C++ functions which are called through thunks.
2952 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2954 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2955 layout. It also supports a TextSeg= and DataSeg= response when only
2956 segment base addresses (rather than offsets) are available.
2958 * The /i format now outputs any trailing branch delay slot instructions
2959 immediately following the last instruction within the count specified.
2961 * The GDB remote protocol "T" stop reply packet now supports a
2962 "library" response. Combined with the new "qXfer:libraries:read"
2963 packet, this response allows GDB to debug shared libraries on targets
2964 where the operating system manages the list of loaded libraries (e.g.
2965 Windows and SymbianOS).
2967 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2968 (DLLs) on Windows and Windows CE targets.
2970 * GDB now supports a faster verification that a .debug file matches its binary
2971 according to its build-id signature, if the signature is present.
2977 Enable or disable hardware flow control (RTS/CTS) on the serial port
2978 when debugging using remote targets.
2980 set mem inaccessible-by-default
2981 show mem inaccessible-by-default
2982 If the target supplies a memory map, for instance via the remote
2983 protocol's "qXfer:memory-map:read" packet, setting this variable
2984 prevents GDB from accessing memory outside the memory map. This
2985 is useful for targets with memory mapped registers or which react
2986 badly to accesses of unmapped address space.
2988 set breakpoint auto-hw
2989 show breakpoint auto-hw
2990 If the target supplies a memory map, for instance via the remote
2991 protocol's "qXfer:memory-map:read" packet, setting this variable
2992 lets GDB use hardware breakpoints automatically for memory regions
2993 where it can not use software breakpoints. This covers both the
2994 "break" command and internal breakpoints used for other commands
2995 including "next" and "finish".
2998 catch exception unhandled
2999 Stop the program execution when Ada exceptions are raised.
3002 Stop the program execution when an Ada assertion failed.
3006 Set an alternate system root for target files. This is a more
3007 general version of "set solib-absolute-prefix", which is now
3008 an alias to "set sysroot".
3011 Provide extended SPU facility status information. This set of
3012 commands is available only when debugging the Cell/B.E. SPU
3015 * New native configurations
3017 OpenBSD/sh sh*-*openbsd*
3020 unset tdesc filename
3022 Use the specified local file as an XML target description, and do
3023 not query the target for its built-in description.
3027 OpenBSD/sh sh*-*-openbsd*
3028 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3029 Toshiba Media Processor mep-elf
3031 * New remote packets
3034 Ignore the specified signals; pass them directly to the debugged program
3035 without stopping other threads or reporting them to GDB.
3037 qXfer:features:read:
3038 Read an XML target description from the target, which describes its
3043 Read or write contents of an spufs file on the target system. These
3044 packets are available only on the Cell/B.E. SPU architecture.
3046 qXfer:libraries:read:
3047 Report the loaded shared libraries. Combined with new "T" packet
3048 response, this packet allows GDB to debug shared libraries on
3049 targets where the operating system manages the list of loaded
3050 libraries (e.g. Windows and SymbianOS).
3054 Support for these obsolete configurations has been removed.
3062 i[34567]86-*-lynxos*
3063 i[34567]86-*-netware*
3064 i[34567]86-*-sco3.2v5*
3065 i[34567]86-*-sco3.2v4*
3067 i[34567]86-*-sysv4.2*
3070 i[34567]86-*-unixware2*
3071 i[34567]86-*-unixware*
3080 * Other removed features
3087 Various m68k-only ROM monitors.
3094 Various Renesas ROM monitors and debugging interfaces for SH and
3099 Support for a Macraigor serial interface to on-chip debugging.
3100 GDB does not directly support the newer parallel or USB
3105 A debug information format. The predecessor to DWARF 2 and
3106 DWARF 3, which are still supported.
3108 Support for the HP aCC compiler on HP-UX/PA-RISC
3110 SOM-encapsulated symbolic debugging information, automatic
3111 invocation of pxdb, and the aCC custom C++ ABI. This does not
3112 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3113 with aCC can still be debugged on an assembly level.
3115 MIPS ".pdr" sections
3117 A MIPS-specific format used to describe stack frame layout
3118 in debugging information.
3122 GDB could work with an older version of Guile to debug
3123 the interpreter and Scheme programs running in it.
3125 set mips stack-arg-size
3126 set mips saved-gpreg-size
3128 Use "set mips abi" to control parameter passing for MIPS.
3130 *** Changes in GDB 6.6
3135 Cell Broadband Engine SPU spu-elf
3137 * GDB can now be configured as a cross-debugger targeting native Windows
3138 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3139 running on a Windows system over TCP/IP to debug Windows programs.
3141 * The GDB remote stub, gdbserver, has been updated to support Windows and
3142 Cygwin debugging. Both single-threaded and multi-threaded programs are
3145 * The "set trust-readonly-sections" command works again. This command was
3146 broken in GDB 6.3, 6.4, and 6.5.
3148 * The "load" command now supports writing to flash memory, if the remote
3149 stub provides the required support.
3151 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3152 longer requires symbolic debug information (e.g. DWARF-2).
3157 unset substitute-path
3158 show substitute-path
3159 Manage a list of substitution rules that GDB uses to rewrite the name
3160 of the directories where the sources are located. This can be useful
3161 for instance when the sources were moved to a different location
3162 between compilation and debugging.
3166 Print each CLI command as it is executed. Each command is prefixed with
3167 a number of `+' symbols representing the nesting depth.
3168 The source command now has a `-v' option to enable the same feature.
3172 The ARM Demon monitor support (RDP protocol, "target rdp").
3174 Kernel Object Display, an embedded debugging feature which only worked with
3175 an obsolete version of Cisco IOS.
3177 The 'set download-write-size' and 'show download-write-size' commands.
3179 * New remote packets
3182 Tell a stub about GDB client features, and request remote target features.
3183 The first feature implemented is PacketSize, which allows the target to
3184 specify the size of packets it can handle - to minimize the number of
3185 packets required and improve performance when connected to a remote
3189 Fetch an OS auxilliary vector from the remote stub. This packet is a
3190 more efficient replacement for qPart:auxv:read.
3192 qXfer:memory-map:read:
3193 Fetch a memory map from the remote stub, including information about
3194 RAM, ROM, and flash memory devices.
3199 Erase and program a flash memory device.
3201 * Removed remote packets
3204 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3205 used it, and only gdbserver implemented it.
3207 *** Changes in GDB 6.5
3211 Renesas M32C/M16C m32c-elf
3213 Morpho Technologies ms1 ms1-elf
3217 init-if-undefined Initialize a convenience variable, but
3218 only if it doesn't already have a value.
3220 The following commands are presently only implemented for native GNU/Linux:
3222 checkpoint Save a snapshot of the program state.
3224 restart <n> Return the program state to a
3225 previously saved state.
3227 info checkpoints List currently saved checkpoints.
3229 delete-checkpoint <n> Delete a previously saved checkpoint.
3231 set|show detach-on-fork Tell gdb whether to detach from a newly
3232 forked process, or to keep debugging it.
3234 info forks List forks of the user program that
3235 are available to be debugged.
3237 fork <n> Switch to debugging one of several
3238 forks of the user program that are
3239 available to be debugged.
3241 delete-fork <n> Delete a fork from the list of forks
3242 that are available to be debugged (and
3243 kill the forked process).
3245 detach-fork <n> Delete a fork from the list of forks
3246 that are available to be debugged (and
3247 allow the process to continue).
3251 Morpho Technologies ms2 ms1-elf
3253 * Improved Windows host support
3255 GDB now builds as a cross debugger hosted on i686-mingw32, including
3256 native console support, and remote communications using either
3257 network sockets or serial ports.
3259 * Improved Modula-2 language support
3261 GDB can now print most types in the Modula-2 syntax. This includes:
3262 basic types, set types, record types, enumerated types, range types,
3263 pointer types and ARRAY types. Procedure var parameters are correctly
3264 printed and hexadecimal addresses and character constants are also
3265 written in the Modula-2 syntax. Best results can be obtained by using
3266 GNU Modula-2 together with the -gdwarf-2 command line option.
3270 The ARM rdi-share module.
3272 The Netware NLM debug server.
3274 *** Changes in GDB 6.4
3276 * New native configurations
3278 OpenBSD/arm arm*-*-openbsd*
3279 OpenBSD/mips64 mips64-*-openbsd*
3283 Morpho Technologies ms1 ms1-elf
3285 * New command line options
3287 --batch-silent As for --batch, but totally silent.
3288 --return-child-result The debugger will exist with the same value
3289 the child (debugged) program exited with.
3290 --eval-command COMMAND, -ex COMMAND
3291 Execute a single GDB CLI command. This may be
3292 specified multiple times and in conjunction
3293 with the --command (-x) option.
3295 * Deprecated commands removed
3297 The following commands, that were deprecated in 2000, have been
3301 set|show arm disassembly-flavor set|show arm disassembler
3302 othernames set arm disassembler
3303 set|show remotedebug set|show debug remote
3304 set|show archdebug set|show debug arch
3305 set|show eventdebug set|show debug event
3308 * New BSD user-level threads support
3310 It is now possible to debug programs using the user-level threads
3311 library on OpenBSD and FreeBSD. Currently supported (target)
3314 FreeBSD/amd64 x86_64-*-freebsd*
3315 FreeBSD/i386 i386-*-freebsd*
3316 OpenBSD/i386 i386-*-openbsd*
3318 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3319 are not yet supported.
3321 * New support for Matsushita MN10300 w/sim added
3322 (Work in progress). mn10300-elf.
3324 * REMOVED configurations and files
3326 VxWorks and the XDR protocol *-*-vxworks
3327 Motorola MCORE mcore-*-*
3328 National Semiconductor NS32000 ns32k-*-*
3330 * New "set print array-indexes" command
3332 After turning this setting "on", GDB prints the index of each element
3333 when displaying arrays. The default is "off" to preserve the previous
3336 * VAX floating point support
3338 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3340 * User-defined command support
3342 In addition to using $arg0..$arg9 for argument passing, it is now possible
3343 to use $argc to determine now many arguments have been passed. See the
3344 section on user-defined commands in the user manual for more information.
3346 *** Changes in GDB 6.3:
3348 * New command line option
3350 GDB now accepts -l followed by a number to set the timeout for remote
3353 * GDB works with GCC -feliminate-dwarf2-dups
3355 GDB now supports a more compact representation of DWARF-2 debug
3356 information using DW_FORM_ref_addr references. These are produced
3357 by GCC with the option -feliminate-dwarf2-dups and also by some
3358 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3359 to use -feliminate-dwarf2-dups.
3361 * Internationalization
3363 When supported by the host system, GDB will be built with
3364 internationalization (libintl). The task of marking up the sources is
3365 continued, we're looking forward to our first translation.
3369 Initial support for debugging programs compiled with the GNAT
3370 implementation of the Ada programming language has been integrated
3371 into GDB. In this release, support is limited to expression evaluation.
3373 * New native configurations
3375 GNU/Linux/m32r m32r-*-linux-gnu
3379 GDB's remote protocol now includes support for the 'p' packet. This
3380 packet is used to fetch individual registers from a remote inferior.
3382 * END-OF-LIFE registers[] compatibility module
3384 GDB's internal register infrastructure has been completely rewritten.
3385 The new infrastructure making possible the implementation of key new
3386 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3389 GDB 6.3 will be the last release to include the the registers[]
3390 compatibility module that allowed out-of-date configurations to
3391 continue to work. This change directly impacts the following
3401 powerpc bdm protocol
3403 Unless there is activity to revive these configurations, they will be
3404 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3406 * OBSOLETE configurations and files
3408 Configurations that have been declared obsolete in this release have
3409 been commented out. Unless there is activity to revive these
3410 configurations, the next release of GDB will have their sources
3411 permanently REMOVED.
3420 *** Changes in GDB 6.2.1:
3422 * MIPS `break main; run' gave an heuristic-fence-post warning
3424 When attempting to run even a simple program, a warning about
3425 heuristic-fence-post being hit would be reported. This problem has
3428 * MIPS IRIX 'long double' crashed GDB
3430 When examining a long double variable, GDB would get a segmentation
3431 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3432 IRIX long double values).
3436 A bug in the VAX stack code was causing problems with the "next"
3437 command. This problem has been fixed.
3439 *** Changes in GDB 6.2:
3441 * Fix for ``many threads''
3443 On GNU/Linux systems that use the NPTL threads library, a program
3444 rapidly creating and deleting threads would confuse GDB leading to the
3447 ptrace: No such process.
3448 thread_db_get_info: cannot get thread info: generic error
3450 This problem has been fixed.
3452 * "-async" and "-noasync" options removed.
3454 Support for the broken "-noasync" option has been removed (it caused
3457 * New ``start'' command.
3459 This command runs the program until the begining of the main procedure.
3461 * New BSD Kernel Data Access Library (libkvm) interface
3463 Using ``target kvm'' it is now possible to debug kernel core dumps and
3464 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3465 platforms. Currently supported (native-only) configurations are:
3467 FreeBSD/amd64 x86_64-*-freebsd*
3468 FreeBSD/i386 i?86-*-freebsd*
3469 NetBSD/i386 i?86-*-netbsd*
3470 NetBSD/m68k m68*-*-netbsd*
3471 NetBSD/sparc sparc-*-netbsd*
3472 OpenBSD/amd64 x86_64-*-openbsd*
3473 OpenBSD/i386 i?86-*-openbsd*
3474 OpenBSD/m68k m68*-openbsd*
3475 OpenBSD/sparc sparc-*-openbsd*
3477 * Signal trampoline code overhauled
3479 Many generic problems with GDB's signal handling code have been fixed.
3480 These include: backtraces through non-contiguous stacks; recognition
3481 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3482 call; backtrace through a signal trampoline; step into and out of
3483 signal handlers; and single-stepping in the signal trampoline.
3485 Please note that kernel bugs are a limiting factor here. These
3486 features have been shown to work on an s390 GNU/Linux system that
3487 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3489 * Cygwin support for DWARF 2 added.
3491 * New native configurations
3493 GNU/Linux/hppa hppa*-*-linux*
3494 OpenBSD/hppa hppa*-*-openbsd*
3495 OpenBSD/m68k m68*-*-openbsd*
3496 OpenBSD/m88k m88*-*-openbsd*
3497 OpenBSD/powerpc powerpc-*-openbsd*
3498 NetBSD/vax vax-*-netbsd*
3499 OpenBSD/vax vax-*-openbsd*
3501 * END-OF-LIFE frame compatibility module
3503 GDB's internal frame infrastructure has been completely rewritten.
3504 The new infrastructure making it possible to support key new features
3505 including DWARF 2 Call Frame Information. To aid in the task of
3506 migrating old configurations to this new infrastructure, a
3507 compatibility module, that allowed old configurations to continue to
3508 work, was also included.
3510 GDB 6.2 will be the last release to include this frame compatibility
3511 module. This change directly impacts the following configurations:
3521 Unless there is activity to revive these configurations, they will be
3522 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3524 * REMOVED configurations and files
3526 Sun 3, running SunOS 3 m68*-*-sunos3*
3527 Sun 3, running SunOS 4 m68*-*-sunos4*
3528 Sun 2, running SunOS 3 m68000-*-sunos3*
3529 Sun 2, running SunOS 4 m68000-*-sunos4*
3530 Motorola 680x0 running LynxOS m68*-*-lynxos*
3531 AT&T 3b1/Unix pc m68*-att-*
3532 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3533 decstation mips-dec-* mips-little-*
3534 riscos mips-*-riscos* mips-*-sysv*
3535 sonymips mips-sony-*
3536 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3538 *** Changes in GDB 6.1.1:
3540 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3542 The TUI (Text-mode User Interface) is now built as part of a default
3543 GDB configuration. It is enabled by either selecting the TUI with the
3544 command line option "-i=tui" or by running the separate "gdbtui"
3545 program. For more information on the TUI, see the manual "Debugging
3548 * Pending breakpoint support (also included in GDB 6.1)
3550 Support has been added to allow you to specify breakpoints in shared
3551 libraries that have not yet been loaded. If a breakpoint location
3552 cannot be found, and the "breakpoint pending" option is set to auto,
3553 GDB queries you if you wish to make the breakpoint pending on a future
3554 shared-library load. If and when GDB resolves the breakpoint symbol,
3555 the pending breakpoint is removed as one or more regular breakpoints
3558 Pending breakpoints are very useful for GCJ Java debugging.
3560 * Fixed ISO-C build problems
3562 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3563 non ISO-C code that stopped them being built using a more strict ISO-C
3564 compiler (e.g., IBM's C compiler).
3566 * Fixed build problem on IRIX 5
3568 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3569 wasn't able to compile compile on an IRIX 5 system.
3571 * Added execute permission to gdb/gdbserver/configure
3573 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3574 permission. This bug would cause configure to fail on a number of
3575 systems (Solaris, IRIX). Ref: server/519.
3577 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3579 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3580 has been updated to use constant array sizes.
3582 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3584 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3585 its generated DWARF Call Frame Info. This encoding was causing GDB to
3586 panic, that panic has been fixed. Ref: gdb/1628.
3588 * Fixed a problem when examining parameters in shared library code.
3590 When examining parameters in optimized shared library code generated
3591 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3592 not available''. GDB now correctly displays the variable's value.
3594 *** Changes in GDB 6.1:
3596 * Removed --with-mmalloc
3598 Support for the mmalloc memory manager has been removed, as it
3599 conflicted with the internal gdb byte cache.
3601 * Changes in AMD64 configurations
3603 The AMD64 target now includes the %cs and %ss registers. As a result
3604 the AMD64 remote protocol has changed; this affects the floating-point
3605 and SSE registers. If you rely on those registers for your debugging,
3606 you should upgrade gdbserver on the remote side.
3608 * Revised SPARC target
3610 The SPARC target has been completely revised, incorporating the
3611 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3612 support for LynxOS and SunOS 4 has been dropped. Calling functions
3613 from within GDB on operating systems with a non-executable stack
3614 (Solaris, OpenBSD) now works.
3618 GDB has a new C++ demangler which does a better job on the mangled
3619 names generated by current versions of g++. It also runs faster, so
3620 with this and other changes gdb should now start faster on large C++
3623 * DWARF 2 Location Expressions
3625 GDB support for location expressions has been extended to support function
3626 arguments and frame bases. Older versions of GDB could crash when they
3629 * C++ nested types and namespaces
3631 GDB's support for nested types and namespaces in C++ has been
3632 improved, especially if you use the DWARF 2 debugging format. (This
3633 is the default for recent versions of GCC on most platforms.)
3634 Specifically, if you have a class "Inner" defined within a class or
3635 namespace "Outer", then GDB realizes that the class's name is
3636 "Outer::Inner", not simply "Inner". This should greatly reduce the
3637 frequency of complaints about not finding RTTI symbols. In addition,
3638 if you are stopped at inside of a function defined within a namespace,
3639 GDB modifies its name lookup accordingly.
3641 * New native configurations
3643 NetBSD/amd64 x86_64-*-netbsd*
3644 OpenBSD/amd64 x86_64-*-openbsd*
3645 OpenBSD/alpha alpha*-*-openbsd*
3646 OpenBSD/sparc sparc-*-openbsd*
3647 OpenBSD/sparc64 sparc64-*-openbsd*
3649 * New debugging protocols
3651 M32R with SDI protocol m32r-*-elf*
3653 * "set prompt-escape-char" command deleted.
3655 The command "set prompt-escape-char" has been deleted. This command,
3656 and its very obscure effet on GDB's prompt, was never documented,
3657 tested, nor mentioned in the NEWS file.
3659 * OBSOLETE configurations and files
3661 Configurations that have been declared obsolete in this release have
3662 been commented out. Unless there is activity to revive these
3663 configurations, the next release of GDB will have their sources
3664 permanently REMOVED.
3666 Sun 3, running SunOS 3 m68*-*-sunos3*
3667 Sun 3, running SunOS 4 m68*-*-sunos4*
3668 Sun 2, running SunOS 3 m68000-*-sunos3*
3669 Sun 2, running SunOS 4 m68000-*-sunos4*
3670 Motorola 680x0 running LynxOS m68*-*-lynxos*
3671 AT&T 3b1/Unix pc m68*-att-*
3672 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3673 decstation mips-dec-* mips-little-*
3674 riscos mips-*-riscos* mips-*-sysv*
3675 sonymips mips-sony-*
3676 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3678 * REMOVED configurations and files
3680 SGI Irix-4.x mips-sgi-irix4 or iris4
3681 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3682 Z8000 simulator z8k-zilog-none or z8ksim
3683 Matsushita MN10200 w/simulator mn10200-*-*
3684 H8/500 simulator h8500-hitachi-hms or h8500hms
3685 HP/PA running BSD hppa*-*-bsd*
3686 HP/PA running OSF/1 hppa*-*-osf*
3687 HP/PA Pro target hppa*-*-pro*
3688 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3689 386BSD i[3456]86-*-bsd*
3690 Sequent family i[3456]86-sequent-sysv4*
3691 i[3456]86-sequent-sysv*
3692 i[3456]86-sequent-bsd*
3693 SPARC running LynxOS sparc-*-lynxos*
3694 SPARC running SunOS 4 sparc-*-sunos4*
3695 Tsqware Sparclet sparclet-*-*
3696 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3698 *** Changes in GDB 6.0:
3702 Support for debugging the Objective-C programming language has been
3703 integrated into GDB.
3705 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3707 DWARF 2's Call Frame Information makes available compiler generated
3708 information that more exactly describes the program's run-time stack.
3709 By using this information, GDB is able to provide more robust stack
3712 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3713 have been updated to use a new backtrace mechanism which includes
3714 DWARF 2 CFI support.
3718 GDB's remote protocol has been extended to include support for hosted
3719 file I/O (where the remote target uses GDB's file system). See GDB's
3720 remote protocol documentation for details.
3722 * All targets using the new architecture framework.
3724 All of GDB's targets have been updated to use the new internal
3725 architecture framework. The way is now open for future GDB releases
3726 to include cross-architecture native debugging support (i386 on amd64,
3729 * GNU/Linux's Thread Local Storage (TLS)
3731 GDB now includes support for for the GNU/Linux implementation of
3732 per-thread variables.
3734 * GNU/Linux's Native POSIX Thread Library (NPTL)
3736 GDB's thread code has been updated to work with either the new
3737 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3739 * Separate debug info.
3741 GDB, in conjunction with BINUTILS, now supports a mechanism for
3742 automatically loading debug information from a separate file. Instead
3743 of shipping full debug and non-debug versions of system libraries,
3744 system integrators can now instead ship just the stripped libraries
3745 and optional debug files.
3747 * DWARF 2 Location Expressions
3749 DWARF 2 Location Expressions allow the compiler to more completely
3750 describe the location of variables (even in optimized code) to the
3753 GDB now includes preliminary support for location expressions (support
3754 for DW_OP_piece is still missing).
3758 A number of long standing bugs that caused GDB to die while starting a
3759 Java application have been fixed. GDB's Java support is now
3760 considered "useable".
3762 * GNU/Linux support for fork, vfork, and exec.
3764 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3765 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3768 * GDB supports logging output to a file
3770 There are two new commands, "set logging" and "show logging", which can be
3771 used to capture GDB's output to a file.
3773 * The meaning of "detach" has changed for gdbserver
3775 The "detach" command will now resume the application, as documented. To
3776 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3779 * d10v, m68hc11 `regs' command deprecated
3781 The `info registers' command has been updated so that it displays the
3782 registers using a format identical to the old `regs' command.
3786 A new command, "maint set profile on/off", has been added. This command can
3787 be used to enable or disable profiling while running GDB, to profile a
3788 session or a set of commands. In addition there is a new configure switch,
3789 "--enable-profiling", which will cause GDB to be compiled with profiling
3790 data, for more informative profiling results.
3792 * Default MI syntax changed to "mi2".
3794 The default MI (machine interface) syntax, enabled by the command line
3795 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3796 "mi1", can be enabled by specifying the option "-i=mi1".
3798 Support for the original "mi0" syntax (included in GDB 5.0) has been
3801 Fix for gdb/192: removed extraneous space when displaying frame level.
3802 Fix for gdb/672: update changelist is now output in mi list format.
3803 Fix for gdb/702: a -var-assign that updates the value now shows up
3804 in a subsequent -var-update.
3806 * New native configurations.
3808 FreeBSD/amd64 x86_64-*-freebsd*
3810 * Multi-arched targets.
3812 HP/PA HPUX11 hppa*-*-hpux*
3813 Renesas M32R/D w/simulator m32r-*-elf*
3815 * OBSOLETE configurations and files
3817 Configurations that have been declared obsolete in this release have
3818 been commented out. Unless there is activity to revive these
3819 configurations, the next release of GDB will have their sources
3820 permanently REMOVED.
3822 Z8000 simulator z8k-zilog-none or z8ksim
3823 Matsushita MN10200 w/simulator mn10200-*-*
3824 H8/500 simulator h8500-hitachi-hms or h8500hms
3825 HP/PA running BSD hppa*-*-bsd*
3826 HP/PA running OSF/1 hppa*-*-osf*
3827 HP/PA Pro target hppa*-*-pro*
3828 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3829 Sequent family i[3456]86-sequent-sysv4*
3830 i[3456]86-sequent-sysv*
3831 i[3456]86-sequent-bsd*
3832 Tsqware Sparclet sparclet-*-*
3833 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3835 * REMOVED configurations and files
3838 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3839 IBM AIX PS/2 i[3456]86-*-aix
3840 i386 running Mach 3.0 i[3456]86-*-mach3*
3841 i386 running Mach i[3456]86-*-mach*
3842 i386 running OSF/1 i[3456]86-*osf1mk*
3843 HP/Apollo 68k Family m68*-apollo*-sysv*,
3845 m68*-hp-bsd*, m68*-hp-hpux*
3846 Argonaut Risc Chip (ARC) arc-*-*
3847 Mitsubishi D30V d30v-*-*
3848 Fujitsu FR30 fr30-*-elf*
3849 OS/9000 i[34]86-*-os9k
3850 I960 with MON960 i960-*-coff
3852 * MIPS $fp behavior changed
3854 The convenience variable $fp, for the MIPS, now consistently returns
3855 the address of the current frame's base. Previously, depending on the
3856 context, $fp could refer to either $sp or the current frame's base
3857 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3858 The GNU Source-Level Debugger''.
3860 *** Changes in GDB 5.3:
3862 * GNU/Linux shared library multi-threaded performance improved.
3864 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3865 `/proc', in preference to `ptrace' for memory reads. This may result
3866 in an improvement in the start-up time of multi-threaded, shared
3867 library applications when run under GDB. One GDB user writes: ``loads
3868 shared libs like mad''.
3870 * ``gdbserver'' now supports multi-threaded applications on some targets
3872 Support for debugging multi-threaded applications which use
3873 the GNU/Linux LinuxThreads package has been added for
3874 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3875 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3877 * GDB now supports C/C++ preprocessor macros.
3879 GDB now expands preprocessor macro invocations in C/C++ expressions,
3880 and provides various commands for showing macro definitions and how
3883 The new command `macro expand EXPRESSION' expands any macro
3884 invocations in expression, and shows the result.
3886 The new command `show macro MACRO-NAME' shows the definition of the
3887 macro named MACRO-NAME, and where it was defined.
3889 Most compilers don't include information about macros in the debugging
3890 information by default. In GCC 3.1, for example, you need to compile
3891 your program with the options `-gdwarf-2 -g3'. If the macro
3892 information is present in the executable, GDB will read it.
3894 * Multi-arched targets.
3896 DEC Alpha (partial) alpha*-*-*
3897 DEC VAX (partial) vax-*-*
3899 National Semiconductor NS32000 (partial) ns32k-*-*
3900 Motorola 68000 (partial) m68k-*-*
3901 Motorola MCORE mcore-*-*
3905 Fujitsu FRV architecture added by Red Hat frv*-*-*
3908 * New native configurations
3910 Alpha NetBSD alpha*-*-netbsd*
3911 SH NetBSD sh*-*-netbsdelf*
3912 MIPS NetBSD mips*-*-netbsd*
3913 UltraSPARC NetBSD sparc64-*-netbsd*
3915 * OBSOLETE configurations and files
3917 Configurations that have been declared obsolete in this release have
3918 been commented out. Unless there is activity to revive these
3919 configurations, the next release of GDB will have their sources
3920 permanently REMOVED.
3922 Mitsubishi D30V d30v-*-*
3923 OS/9000 i[34]86-*-os9k
3924 IBM AIX PS/2 i[3456]86-*-aix
3925 Fujitsu FR30 fr30-*-elf*
3926 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3927 Argonaut Risc Chip (ARC) arc-*-*
3928 i386 running Mach 3.0 i[3456]86-*-mach3*
3929 i386 running Mach i[3456]86-*-mach*
3930 i386 running OSF/1 i[3456]86-*osf1mk*
3931 HP/Apollo 68k Family m68*-apollo*-sysv*,
3933 m68*-hp-bsd*, m68*-hp-hpux*
3934 I960 with MON960 i960-*-coff
3936 * OBSOLETE languages
3938 CHILL, a Pascal like language used by telecommunications companies.
3940 * REMOVED configurations and files
3942 AMD 29k family via UDI a29k-amd-udi, udi29k
3943 A29K VxWorks a29k-*-vxworks
3944 AMD 29000 embedded, using EBMON a29k-none-none
3945 AMD 29000 embedded with COFF a29k-none-coff
3946 AMD 29000 embedded with a.out a29k-none-aout
3948 testsuite/gdb.hp/gdb.threads-hp/ directory
3950 * New command "set max-user-call-depth <nnn>"
3952 This command allows the user to limit the call depth of user-defined
3953 commands. The default is 1024.
3955 * Changes in FreeBSD/i386 native debugging.
3957 Support for the "generate-core-file" has been added.
3959 * New commands "dump", "append", and "restore".
3961 These commands allow data to be copied from target memory
3962 to a bfd-format or binary file (dump and append), and back
3963 from a file into memory (restore).
3965 * Improved "next/step" support on multi-processor Alpha Tru64.
3967 The previous single-step mechanism could cause unpredictable problems,
3968 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3969 of a software single-step mechanism prevents this.
3971 *** Changes in GDB 5.2.1:
3979 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3980 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3981 Fix, by Joel Brobecker imported from mainline.
3983 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3984 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3985 Fix, by Fred Fish, imported from mainline.
3987 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3988 Surprisingly enough, it works now.
3989 By Michal Ludvig, imported from mainline.
3991 i386 hardware watchpoint support:
3992 avoid misses on second run for some targets.
3993 By Pierre Muller, imported from mainline.
3995 *** Changes in GDB 5.2:
3997 * New command "set trust-readonly-sections on[off]".
3999 This command is a hint that tells gdb that read-only sections
4000 really are read-only (ie. that their contents will not change).
4001 In this mode, gdb will go to the object file rather than the
4002 target to read memory from read-only sections (such as ".text").
4003 This can be a significant performance improvement on some
4004 (notably embedded) targets.
4006 * New command "generate-core-file" (or "gcore").
4008 This new gdb command allows the user to drop a core file of the child
4009 process state at any time. So far it's been implemented only for
4010 GNU/Linux and Solaris, but should be relatively easily ported to other
4011 hosts. Argument is core file name (defaults to core.<pid>).
4013 * New command line option
4015 GDB now accepts --pid or -p followed by a process id.
4017 * Change in command line behavior -- corefiles vs. process ids.
4019 There is a subtle behavior in the way in which GDB handles
4020 command line arguments. The first non-flag argument is always
4021 a program to debug, but the second non-flag argument may either
4022 be a corefile or a process id. Previously, GDB would attempt to
4023 open the second argument as a corefile, and if that failed, would
4024 issue a superfluous error message and then attempt to attach it as
4025 a process. Now, if the second argument begins with a non-digit,
4026 it will be treated as a corefile. If it begins with a digit,
4027 GDB will attempt to attach it as a process, and if no such process
4028 is found, will then attempt to open it as a corefile.
4030 * Changes in ARM configurations.
4032 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4033 configuration is fully multi-arch.
4035 * New native configurations
4037 ARM NetBSD arm*-*-netbsd*
4038 x86 OpenBSD i[3456]86-*-openbsd*
4039 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4040 Sparc64 running FreeBSD sparc64-*-freebsd*
4044 Sanyo XStormy16 xstormy16-elf
4046 * OBSOLETE configurations and files
4048 Configurations that have been declared obsolete in this release have
4049 been commented out. Unless there is activity to revive these
4050 configurations, the next release of GDB will have their sources
4051 permanently REMOVED.
4053 AMD 29k family via UDI a29k-amd-udi, udi29k
4054 A29K VxWorks a29k-*-vxworks
4055 AMD 29000 embedded, using EBMON a29k-none-none
4056 AMD 29000 embedded with COFF a29k-none-coff
4057 AMD 29000 embedded with a.out a29k-none-aout
4059 testsuite/gdb.hp/gdb.threads-hp/ directory
4061 * REMOVED configurations and files
4063 TI TMS320C80 tic80-*-*
4065 PowerPC Solaris powerpcle-*-solaris*
4066 PowerPC Windows NT powerpcle-*-cygwin32
4067 PowerPC Netware powerpc-*-netware*
4068 Harris/CXUX m88k m88*-harris-cxux*
4069 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4070 ns32k-utek-sysv* ns32k-utek-*
4071 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4072 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4073 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4074 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4075 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4077 * Changes to command line processing
4079 The new `--args' feature can be used to specify command-line arguments
4080 for the inferior from gdb's command line.
4082 * Changes to key bindings
4084 There is a new `operate-and-get-next' function bound to `C-o'.
4086 *** Changes in GDB 5.1.1
4088 Fix compile problem on DJGPP.
4090 Fix a problem with floating-point registers on the i386 being
4093 Fix to stop GDB crashing on .debug_str debug info.
4095 Numerous documentation fixes.
4097 Numerous testsuite fixes.
4099 *** Changes in GDB 5.1:
4101 * New native configurations
4103 Alpha FreeBSD alpha*-*-freebsd*
4104 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4105 MIPS GNU/Linux mips*-*-linux*
4106 MIPS SGI Irix 6.x mips*-sgi-irix6*
4107 ia64 AIX ia64-*-aix*
4108 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4112 Motorola 68HC11 and 68HC12 m68hc11-elf
4114 UltraSparc running GNU/Linux sparc64-*-linux*
4116 * OBSOLETE configurations and files
4118 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4119 Harris/CXUX m88k m88*-harris-cxux*
4120 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4121 ns32k-utek-sysv* ns32k-utek-*
4122 TI TMS320C80 tic80-*-*
4124 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4125 PowerPC Solaris powerpcle-*-solaris*
4126 PowerPC Windows NT powerpcle-*-cygwin32
4127 PowerPC Netware powerpc-*-netware*
4128 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4129 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4130 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4131 Apple Macintosh (MPW) host N/A
4133 stuff.c (Program to stuff files into a specially prepared space in kdb)
4134 kdb-start.c (Main loop for the standalone kernel debugger)
4136 Configurations that have been declared obsolete in this release have
4137 been commented out. Unless there is activity to revive these
4138 configurations, the next release of GDB will have their sources
4139 permanently REMOVED.
4141 * REMOVED configurations and files
4143 Altos 3068 m68*-altos-*
4144 Convex c1-*-*, c2-*-*
4146 ARM RISCix arm-*-* (as host)
4150 * GDB has been converted to ISO C.
4152 GDB's source code has been converted to ISO C. In particular, the
4153 sources are fully protoized, and rely on standard headers being
4158 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4160 * The MI enabled by default.
4162 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4163 revised and enabled by default. Packages which use GDB as a debugging
4164 engine behind a UI or another front end are encouraged to switch to
4165 using the GDB/MI interface, instead of the old annotations interface
4166 which is now deprecated.
4168 * Support for debugging Pascal programs.
4170 GDB now includes support for debugging Pascal programs. The following
4171 main features are supported:
4173 - Pascal-specific data types such as sets;
4175 - automatic recognition of Pascal sources based on file-name
4178 - Pascal-style display of data types, variables, and functions;
4180 - a Pascal expression parser.
4182 However, some important features are not yet supported.
4184 - Pascal string operations are not supported at all;
4186 - there are some problems with boolean types;
4188 - Pascal type hexadecimal constants are not supported
4189 because they conflict with the internal variables format;
4191 - support for Pascal objects and classes is not full yet;
4193 - unlike Pascal, GDB is case-sensitive for symbol names.
4195 * Changes in completion.
4197 Commands such as `shell', `run' and `set args', which pass arguments
4198 to inferior programs, now complete on file names, similar to what
4199 users expect at the shell prompt.
4201 Commands which accept locations, such as `disassemble', `print',
4202 `breakpoint', `until', etc. now complete on filenames as well as
4203 program symbols. Thus, if you type "break foob TAB", and the source
4204 files linked into the programs include `foobar.c', that file name will
4205 be one of the candidates for completion. However, file names are not
4206 considered for completion after you typed a colon that delimits a file
4207 name from a name of a function in that file, as in "break foo.c:bar".
4209 `set demangle-style' completes on available demangling styles.
4211 * New platform-independent commands:
4213 It is now possible to define a post-hook for a command as well as a
4214 hook that runs before the command. For more details, see the
4215 documentation of `hookpost' in the GDB manual.
4217 * Changes in GNU/Linux native debugging.
4219 Support for debugging multi-threaded programs has been completely
4220 revised for all platforms except m68k and sparc. You can now debug as
4221 many threads as your system allows you to have.
4223 Attach/detach is supported for multi-threaded programs.
4225 Support for SSE registers was added for x86. This doesn't work for
4226 multi-threaded programs though.
4228 * Changes in MIPS configurations.
4230 Multi-arch support is enabled for all MIPS configurations.
4232 GDB can now be built as native debugger on SGI Irix 6.x systems for
4233 debugging n32 executables. (Debugging 64-bit executables is not yet
4236 * Unified support for hardware watchpoints in all x86 configurations.
4238 Most (if not all) native x86 configurations support hardware-assisted
4239 breakpoints and watchpoints in a unified manner. This support
4240 implements debug register sharing between watchpoints, which allows to
4241 put a virtually infinite number of watchpoints on the same address,
4242 and also supports watching regions up to 16 bytes with several debug
4245 The new maintenance command `maintenance show-debug-regs' toggles
4246 debugging print-outs in functions that insert, remove, and test
4247 watchpoints and hardware breakpoints.
4249 * Changes in the DJGPP native configuration.
4251 New command ``info dos sysinfo'' displays assorted information about
4252 the CPU, OS, memory, and DPMI server.
4254 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4255 display information about segment descriptors stored in GDT, LDT, and
4258 New commands ``info dos pde'' and ``info dos pte'' display entries
4259 from Page Directory and Page Tables (for now works with CWSDPMI only).
4260 New command ``info dos address-pte'' displays the Page Table entry for
4261 a given linear address.
4263 GDB can now pass command lines longer than 126 characters to the
4264 program being debugged (requires an update to the libdbg.a library
4265 which is part of the DJGPP development kit).
4267 DWARF2 debug info is now supported.
4269 It is now possible to `step' and `next' through calls to `longjmp'.
4271 * Changes in documentation.
4273 All GDB documentation was converted to GFDL, the GNU Free
4274 Documentation License.
4276 Tracepoints-related commands are now fully documented in the GDB
4279 TUI, the Text-mode User Interface, is now documented in the manual.
4281 Tracepoints-related commands are now fully documented in the GDB
4284 The "GDB Internals" manual now has an index. It also includes
4285 documentation of `ui_out' functions, GDB coding standards, x86
4286 hardware watchpoints, and memory region attributes.
4288 * GDB's version number moved to ``version.in''
4290 The Makefile variable VERSION has been replaced by the file
4291 ``version.in''. People creating GDB distributions should update the
4292 contents of this file.
4296 GUD support is now a standard part of the EMACS distribution.
4298 *** Changes in GDB 5.0:
4300 * Improved support for debugging FP programs on x86 targets
4302 Unified and much-improved support for debugging floating-point
4303 programs on all x86 targets. In particular, ``info float'' now
4304 displays the FP registers in the same format on all x86 targets, with
4305 greater level of detail.
4307 * Improvements and bugfixes in hardware-assisted watchpoints
4309 It is now possible to watch array elements, struct members, and
4310 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4311 on x86 targets no longer erroneously trigger when the address is
4314 * Improvements in the native DJGPP version of GDB
4316 The distribution now includes all the scripts and auxiliary files
4317 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4318 machines ``out of the box''.
4320 The DJGPP version can now debug programs that use signals. It is
4321 possible to catch signals that happened in the debuggee, deliver
4322 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4323 would kill the program being debugged.) Programs that hook hardware
4324 interrupts (keyboard, timer, etc.) can also be debugged.
4326 It is now possible to debug DJGPP programs that redirect their
4327 standard handles or switch them to raw (as opposed to cooked) mode, or
4328 even close them. The command ``run < foo > bar'' works as expected,
4329 and ``info terminal'' reports useful information about the debuggee's
4330 terminal, including raw/cooked mode, redirection, etc.
4332 The DJGPP version now uses termios functions for console I/O, which
4333 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4336 DOS-style file names with drive letters are now fully supported by
4339 It is now possible to debug DJGPP programs that switch their working
4340 directory. It is also possible to rerun the debuggee any number of
4341 times without restarting GDB; thus, you can use the same setup,
4342 breakpoints, etc. for many debugging sessions.
4344 * New native configurations
4346 ARM GNU/Linux arm*-*-linux*
4347 PowerPC GNU/Linux powerpc-*-linux*
4351 Motorola MCore mcore-*-*
4352 x86 VxWorks i[3456]86-*-vxworks*
4353 PowerPC VxWorks powerpc-*-vxworks*
4354 TI TMS320C80 tic80-*-*
4356 * OBSOLETE configurations
4358 Altos 3068 m68*-altos-*
4359 Convex c1-*-*, c2-*-*
4361 ARM RISCix arm-*-* (as host)
4364 Configurations that have been declared obsolete will be commented out,
4365 but the code will be left in place. If there is no activity to revive
4366 these configurations before the next release of GDB, the sources will
4367 be permanently REMOVED.
4369 * Gould support removed
4371 Support for the Gould PowerNode and NP1 has been removed.
4373 * New features for SVR4
4375 On SVR4 native platforms (such as Solaris), if you attach to a process
4376 without first loading a symbol file, GDB will now attempt to locate and
4377 load symbols from the running process's executable file.
4379 * Many C++ enhancements
4381 C++ support has been greatly improved. Overload resolution now works properly
4382 in almost all cases. RTTI support is on the way.
4384 * Remote targets can connect to a sub-program
4386 A popen(3) style serial-device has been added. This device starts a
4387 sub-process (such as a stand-alone simulator) and then communicates
4388 with that. The sub-program to run is specified using the syntax
4389 ``|<program> <args>'' vis:
4391 (gdb) set remotedebug 1
4392 (gdb) target extended-remote |mn10300-elf-sim program-args
4394 * MIPS 64 remote protocol
4396 A long standing bug in the mips64 remote protocol where by GDB
4397 expected certain 32 bit registers (ex SR) to be transfered as 32
4398 instead of 64 bits has been fixed.
4400 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4401 added to provide backward compatibility with older versions of GDB.
4403 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4405 The command ``set remotebinarydownload'' command has been replaced by
4406 ``set remote X-packet''. Other commands in ``set remote'' family
4407 include ``set remote P-packet''.
4409 * Breakpoint commands accept ranges.
4411 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4412 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4413 ``tracepoint passcount'' also accepts a range of tracepoints.
4415 * ``apropos'' command added.
4417 The ``apropos'' command searches through command names and
4418 documentation strings, printing out matches, making it much easier to
4419 try to find a command that does what you are looking for.
4423 A new machine oriented interface (MI) has been added to GDB. This
4424 interface is designed for debug environments running GDB as a separate
4425 process. This is part of the long term libGDB project. See the
4426 "GDB/MI" chapter of the GDB manual for further information. It can be
4427 enabled by configuring with:
4429 .../configure --enable-gdbmi
4431 *** Changes in GDB-4.18:
4433 * New native configurations
4435 HP-UX 10.20 hppa*-*-hpux10.20
4436 HP-UX 11.x hppa*-*-hpux11.0*
4437 M68K GNU/Linux m68*-*-linux*
4441 Fujitsu FR30 fr30-*-elf*
4442 Intel StrongARM strongarm-*-*
4443 Mitsubishi D30V d30v-*-*
4445 * OBSOLETE configurations
4447 Gould PowerNode, NP1 np1-*-*, pn-*-*
4449 Configurations that have been declared obsolete will be commented out,
4450 but the code will be left in place. If there is no activity to revive
4451 these configurations before the next release of GDB, the sources will
4452 be permanently REMOVED.
4456 As a compatibility experiment, GDB's source files buildsym.h and
4457 buildsym.c have been converted to pure standard C, no longer
4458 containing any K&R compatibility code. We believe that all systems in
4459 use today either come with a standard C compiler, or have a GCC port
4460 available. If this is not true, please report the affected
4461 configuration to bug-gdb@gnu.org immediately. See the README file for
4462 information about getting a standard C compiler if you don't have one
4467 GDB now uses readline 2.2.
4469 * set extension-language
4471 You can now control the mapping between filename extensions and source
4472 languages by using the `set extension-language' command. For instance,
4473 you can ask GDB to treat .c files as C++ by saying
4474 set extension-language .c c++
4475 The command `info extensions' lists all of the recognized extensions
4476 and their associated languages.
4478 * Setting processor type for PowerPC and RS/6000
4480 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4481 you can use the `set processor' command to specify what variant of the
4482 PowerPC family you are debugging. The command
4486 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4487 following PowerPC and RS6000 variants:
4489 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4490 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4492 403GC IBM PowerPC 403GC
4493 505 Motorola PowerPC 505
4494 860 Motorola PowerPC 860 or 850
4495 601 Motorola PowerPC 601
4496 602 Motorola PowerPC 602
4497 603 Motorola/IBM PowerPC 603 or 603e
4498 604 Motorola PowerPC 604 or 604e
4499 750 Motorola/IBM PowerPC 750 or 750
4501 At the moment, this command just tells GDB what to name the
4502 special-purpose processor registers. Since almost all the affected
4503 registers are inaccessible to user-level programs, this command is
4504 only useful for remote debugging in its present form.
4508 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4509 more extensive support for HP-UX. Added features include shared
4510 library support, kernel threads and hardware watchpoints for 11.00,
4511 support for HP's ANSI C and C++ compilers, and a compatibility mode
4512 for xdb and dbx commands.
4516 HP's donation includes the new concept of catchpoints, which is a
4517 generalization of the old catch command. On HP-UX, it is now possible
4518 to catch exec, fork, and vfork, as well as library loading.
4520 This means that the existing catch command has changed; its first
4521 argument now specifies the type of catch to be set up. See the
4522 output of "help catch" for a list of catchpoint types.
4524 * Debugging across forks
4526 On HP-UX, you can choose which process to debug when a fork() happens
4531 HP has donated a curses-based terminal user interface (TUI). To get
4532 it, build with --enable-tui. Although this can be enabled for any
4533 configuration, at present it only works for native HP debugging.
4535 * GDB remote protocol additions
4537 A new protocol packet 'X' that writes binary data is now available.
4538 Default behavior is to try 'X', then drop back to 'M' if the stub
4539 fails to respond. The settable variable `remotebinarydownload'
4540 allows explicit control over the use of 'X'.
4542 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4543 full 64-bit address. The command
4545 set remoteaddresssize 32
4547 can be used to revert to the old behaviour. For existing remote stubs
4548 the change should not be noticed, as the additional address information
4551 In order to assist in debugging stubs, you may use the maintenance
4552 command `packet' to send any text string to the stub. For instance,
4554 maint packet heythere
4556 sends the packet "$heythere#<checksum>". Note that it is very easy to
4557 disrupt a debugging session by sending the wrong packet at the wrong
4560 The compare-sections command allows you to compare section data on the
4561 target to what is in the executable file without uploading or
4562 downloading, by comparing CRC checksums.
4564 * Tracing can collect general expressions
4566 You may now collect general expressions at tracepoints. This requires
4567 further additions to the target-side stub; see tracepoint.c and
4568 doc/agentexpr.texi for further details.
4570 * mask-address variable for Mips
4572 For Mips targets, you may control the zeroing of the upper 32 bits of
4573 a 64-bit address by entering `set mask-address on'. This is mainly
4574 of interest to users of embedded R4xxx and R5xxx processors.
4576 * Higher serial baud rates
4578 GDB's serial code now allows you to specify baud rates 57600, 115200,
4579 230400, and 460800 baud. (Note that your host system may not be able
4580 to achieve all of these rates.)
4584 The i960 configuration now includes an initial implementation of a
4585 builtin simulator, contributed by Jim Wilson.
4588 *** Changes in GDB-4.17:
4590 * New native configurations
4592 Alpha GNU/Linux alpha*-*-linux*
4593 Unixware 2.x i[3456]86-unixware2*
4594 Irix 6.x mips*-sgi-irix6*
4595 PowerPC GNU/Linux powerpc-*-linux*
4596 PowerPC Solaris powerpcle-*-solaris*
4597 Sparc GNU/Linux sparc-*-linux*
4598 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4602 Argonaut Risc Chip (ARC) arc-*-*
4603 Hitachi H8/300S h8300*-*-*
4604 Matsushita MN10200 w/simulator mn10200-*-*
4605 Matsushita MN10300 w/simulator mn10300-*-*
4606 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4607 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4608 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4609 Mitsubishi D10V w/simulator d10v-*-*
4610 Mitsubishi M32R/D w/simulator m32r-*-elf*
4611 Tsqware Sparclet sparclet-*-*
4612 NEC V850 w/simulator v850-*-*
4614 * New debugging protocols
4616 ARM with RDI protocol arm*-*-*
4617 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4618 DDB and LSI variants of PMON protocol mips*-*-*
4619 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4620 PowerPC with SDS protocol powerpc{,le}-*-eabi
4621 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4625 All configurations can now understand and use the DWARF 2 debugging
4626 format. The choice is automatic, if the symbol file contains DWARF 2
4631 GDB now includes basic Java language support. This support is
4632 only useful with Java compilers that produce native machine code.
4634 * solib-absolute-prefix and solib-search-path
4636 For SunOS and SVR4 shared libraries, you may now set the prefix for
4637 loading absolute shared library symbol files, and the search path for
4638 locating non-absolute shared library symbol files.
4640 * Live range splitting
4642 GDB can now effectively debug code for which GCC has performed live
4643 range splitting as part of its optimization. See gdb/doc/LRS for
4644 more details on the expected format of the stabs information.
4648 GDB's support for the GNU Hurd, including thread debugging, has been
4649 updated to work with current versions of the Hurd.
4653 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4654 instruction set. ARM GDB automatically detects when Thumb
4655 instructions are in use, and adjusts disassembly and backtracing
4660 GDB's MIPS target configurations now handle the MIP16 16-bit
4665 GDB now includes support for overlays; if an executable has been
4666 linked such that multiple sections are based at the same address, GDB
4667 will decide which section to use for symbolic info. You can choose to
4668 control the decision manually, using overlay commands, or implement
4669 additional target-side support and use "overlay load-target" to bring
4670 in the overlay mapping. Do "help overlay" for more detail.
4674 The command "info symbol <address>" displays information about
4675 the symbol at the specified address.
4679 The standard remote protocol now includes an extension that allows
4680 asynchronous collection and display of trace data. This requires
4681 extensive support in the target-side debugging stub. Tracing mode
4682 includes a new interaction mode in GDB and new commands: see the
4683 file tracepoint.c for more details.
4687 Configurations for embedded MIPS now include a simulator contributed
4688 by Cygnus Solutions. The simulator supports the instruction sets
4689 of most MIPS variants.
4693 Sparc configurations may now include the ERC32 simulator contributed
4694 by the European Space Agency. The simulator is not built into
4695 Sparc targets by default; configure with --enable-sim to include it.
4699 For target configurations that may include multiple variants of a
4700 basic architecture (such as MIPS and SH), you may now set the
4701 architecture explicitly. "set arch" sets, "info arch" lists
4702 the possible architectures.
4704 *** Changes in GDB-4.16:
4706 * New native configurations
4708 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4709 M68K NetBSD m68k-*-netbsd*
4710 PowerPC AIX 4.x powerpc-*-aix*
4711 PowerPC MacOS powerpc-*-macos*
4712 PowerPC Windows NT powerpcle-*-cygwin32
4713 RS/6000 AIX 4.x rs6000-*-aix4*
4717 ARM with RDP protocol arm-*-*
4718 I960 with MON960 i960-*-coff
4719 MIPS VxWorks mips*-*-vxworks*
4720 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4721 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4723 Matra Sparclet sparclet-*-*
4727 The powerpc-eabi configuration now includes the PSIM simulator,
4728 contributed by Andrew Cagney, with assistance from Mike Meissner.
4729 PSIM is a very elaborate model of the PowerPC, including not only
4730 basic instruction set execution, but also details of execution unit
4731 performance and I/O hardware. See sim/ppc/README for more details.
4735 GDB now works with Solaris 2.5.
4737 * Windows 95/NT native
4739 GDB will now work as a native debugger on Windows 95 and Windows NT.
4740 To build it from source, you must use the "gnu-win32" environment,
4741 which uses a DLL to emulate enough of Unix to run the GNU tools.
4742 Further information, binaries, and sources are available at
4743 ftp.cygnus.com, under pub/gnu-win32.
4745 * dont-repeat command
4747 If a user-defined command includes the command `dont-repeat', then the
4748 command will not be repeated if the user just types return. This is
4749 useful if the command is time-consuming to run, so that accidental
4750 extra keystrokes don't run the same command many times.
4752 * Send break instead of ^C
4754 The standard remote protocol now includes an option to send a break
4755 rather than a ^C to the target in order to interrupt it. By default,
4756 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4758 * Remote protocol timeout
4760 The standard remote protocol includes a new variable `remotetimeout'
4761 that allows you to set the number of seconds before GDB gives up trying
4762 to read from the target. The default value is 2.
4764 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4766 By default GDB will automatically keep track of objects as they are
4767 loaded and unloaded by the dynamic linker. By using the command `set
4768 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4769 when shared library events occur, thus allowing you to set breakpoints
4770 in shared libraries which are explicitly loaded by the inferior.
4772 Note this feature does not work on hpux8. On hpux9 you must link
4773 /usr/lib/end.o into your program. This feature should work
4774 automatically on hpux10.
4776 * Irix 5.x hardware watchpoint support
4778 Irix 5 configurations now support the use of hardware watchpoints.
4780 * Mips protocol "SYN garbage limit"
4782 When debugging a Mips target using the `target mips' protocol, you
4783 may set the number of characters that GDB will ignore by setting
4784 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4785 every character. The default value is 1050.
4787 * Recording and replaying remote debug sessions
4789 If you set `remotelogfile' to the name of a file, gdb will write to it
4790 a recording of a remote debug session. This recording may then be
4791 replayed back to gdb using "gdbreplay". See gdbserver/README for
4792 details. This is useful when you have a problem with GDB while doing
4793 remote debugging; you can make a recording of the session and send it
4794 to someone else, who can then recreate the problem.
4796 * Speedups for remote debugging
4798 GDB includes speedups for downloading and stepping MIPS systems using
4799 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4800 and more efficient S-record downloading.
4802 * Memory use reductions and statistics collection
4804 GDB now uses less memory and reports statistics about memory usage.
4805 Try the `maint print statistics' command, for example.
4807 *** Changes in GDB-4.15:
4809 * Psymtabs for XCOFF
4811 The symbol reader for AIX GDB now uses partial symbol tables. This
4812 can greatly improve startup time, especially for large executables.
4814 * Remote targets use caching
4816 Remote targets now use a data cache to speed up communication with the
4817 remote side. The data cache could lead to incorrect results because
4818 it doesn't know about volatile variables, thus making it impossible to
4819 debug targets which use memory mapped I/O devices. `set remotecache
4820 off' turns the the data cache off.
4822 * Remote targets may have threads
4824 The standard remote protocol now includes support for multiple threads
4825 in the target system, using new protocol commands 'H' and 'T'. See
4826 gdb/remote.c for details.
4830 If GDB is configured with `--enable-netrom', then it will include
4831 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4832 acts as though it is a bank of ROM on the target board, but you can
4833 write into it over the network. GDB's support consists only of
4834 support for fast loading into the emulated ROM; to debug, you must use
4835 another protocol, such as standard remote protocol. The usual
4836 sequence is something like
4838 target nrom <netrom-hostname>
4840 target remote <netrom-hostname>:1235
4844 GDB now includes support for the Apple Macintosh, as a host only. It
4845 may be run as either an MPW tool or as a standalone application, and
4846 it can debug through the serial port. All the usual GDB commands are
4847 available, but to the target command, you must supply "serial" as the
4848 device type instead of "/dev/ttyXX". See mpw-README in the main
4849 directory for more information on how to build. The MPW configuration
4850 scripts */mpw-config.in support only a few targets, and only the
4851 mips-idt-ecoff target has been tested.
4855 GDB configuration now uses autoconf. This is not user-visible,
4856 but does simplify configuration and building.
4860 GDB now supports hpux10.
4862 *** Changes in GDB-4.14:
4864 * New native configurations
4866 x86 FreeBSD i[345]86-*-freebsd
4867 x86 NetBSD i[345]86-*-netbsd
4868 NS32k NetBSD ns32k-*-netbsd
4869 Sparc NetBSD sparc-*-netbsd
4873 A29K VxWorks a29k-*-vxworks
4874 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4875 CPU32 EST-300 emulator m68*-*-est*
4876 PowerPC ELF powerpc-*-elf
4879 * Alpha OSF/1 support for procfs
4881 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4882 possible to attach to running processes. As the mounting of the /proc
4883 filesystem is optional on the Alpha, GDB automatically determines
4884 the availability of /proc during startup. This can lead to problems
4885 if /proc is unmounted after GDB has been started.
4887 * Arguments to user-defined commands
4889 User commands may accept up to 10 arguments separated by whitespace.
4890 Arguments are accessed within the user command via $arg0..$arg9. A
4893 print $arg0 + $arg1 + $arg2
4895 To execute the command use:
4898 Defines the command "adder" which prints the sum of its three arguments.
4899 Note the arguments are text substitutions, so they may reference variables,
4900 use complex expressions, or even perform inferior function calls.
4902 * New `if' and `while' commands
4904 This makes it possible to write more sophisticated user-defined
4905 commands. Both commands take a single argument, which is the
4906 expression to evaluate, and must be followed by the commands to
4907 execute, one per line, if the expression is nonzero, the list being
4908 terminated by the word `end'. The `if' command list may include an
4909 `else' word, which causes the following commands to be executed only
4910 if the expression is zero.
4912 * Fortran source language mode
4914 GDB now includes partial support for Fortran 77. It will recognize
4915 Fortran programs and can evaluate a subset of Fortran expressions, but
4916 variables and functions may not be handled correctly. GDB will work
4917 with G77, but does not yet know much about symbols emitted by other
4920 * Better HPUX support
4922 Most debugging facilities now work on dynamic executables for HPPAs
4923 running hpux9 or later. You can attach to running dynamically linked
4924 processes, but by default the dynamic libraries will be read-only, so
4925 for instance you won't be able to put breakpoints in them. To change
4926 that behavior do the following before running the program:
4932 This will cause the libraries to be mapped private and read-write.
4933 To revert to the normal behavior, do this:
4939 You cannot set breakpoints or examine data in the library until after
4940 the library is loaded if the function/data symbols do not have
4943 GDB can now also read debug symbols produced by the HP C compiler on
4944 HPPAs (sorry, no C++, Fortran or 68k support).
4946 * Target byte order now dynamically selectable
4948 You can choose which byte order to use with a target system, via the
4949 commands "set endian big" and "set endian little", and you can see the
4950 current setting by using "show endian". You can also give the command
4951 "set endian auto", in which case GDB will use the byte order
4952 associated with the executable. Currently, only embedded MIPS
4953 configurations support dynamic selection of target byte order.
4955 * New DOS host serial code
4957 This version uses DPMI interrupts to handle buffered I/O, so you
4958 no longer need to run asynctsr when debugging boards connected to
4961 *** Changes in GDB-4.13:
4963 * New "complete" command
4965 This lists all the possible completions for the rest of the line, if it
4966 were to be given as a command itself. This is intended for use by emacs.
4968 * Trailing space optional in prompt
4970 "set prompt" no longer adds a space for you after the prompt you set. This
4971 allows you to set a prompt which ends in a space or one that does not.
4973 * Breakpoint hit counts
4975 "info break" now displays a count of the number of times the breakpoint
4976 has been hit. This is especially useful in conjunction with "ignore"; you
4977 can ignore a large number of breakpoint hits, look at the breakpoint info
4978 to see how many times the breakpoint was hit, then run again, ignoring one
4979 less than that number, and this will get you quickly to the last hit of
4982 * Ability to stop printing at NULL character
4984 "set print null-stop" will cause GDB to stop printing the characters of
4985 an array when the first NULL is encountered. This is useful when large
4986 arrays actually contain only short strings.
4988 * Shared library breakpoints
4990 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4991 breakpoints in shared libraries before the executable is run.
4993 * Hardware watchpoints
4995 There is a new hardware breakpoint for the watch command for sparclite
4996 targets. See gdb/sparclite/hw_breakpoint.note.
4998 Hardware watchpoints are also now supported under GNU/Linux.
5002 Annotations have been added. These are for use with graphical interfaces,
5003 and are still experimental. Currently only gdba.el uses these.
5005 * Improved Irix 5 support
5007 GDB now works properly with Irix 5.2.
5009 * Improved HPPA support
5011 GDB now works properly with the latest GCC and GAS.
5013 * New native configurations
5015 Sequent PTX4 i[34]86-sequent-ptx4
5016 HPPA running OSF/1 hppa*-*-osf*
5017 Atari TT running SVR4 m68*-*-sysv4*
5018 RS/6000 LynxOS rs6000-*-lynxos*
5022 OS/9000 i[34]86-*-os9k
5023 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5026 * Hitachi SH7000 and E7000-PC ICE support
5028 There is now support for communicating with the Hitachi E7000-PC ICE.
5029 This is available automatically when GDB is configured for the SH.
5033 As usual, a variety of small fixes and improvements, both generic
5034 and configuration-specific. See the ChangeLog for more detail.
5036 *** Changes in GDB-4.12:
5038 * Irix 5 is now supported
5042 GDB-4.12 on the HPPA has a number of changes which make it unable
5043 to debug the output from the currently released versions of GCC and
5044 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5045 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5046 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5049 *** Changes in GDB-4.11:
5051 * User visible changes:
5055 The "set remotedebug" option is now consistent between the mips remote
5056 target, remote targets using the gdb-specific protocol, UDI (AMD's
5057 debug protocol for the 29k) and the 88k bug monitor. It is now an
5058 integer specifying a debug level (normally 0 or 1, but 2 means more
5059 debugging info for the mips target).
5061 * DEC Alpha native support
5063 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5064 debug info, but GDB works fairly well with the DEC compiler and should
5065 work with a future GCC release. See the README file for a few
5066 Alpha-specific notes.
5068 * Preliminary thread implementation
5070 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5072 * LynxOS native and target support for 386
5074 This release has been hosted on LynxOS 2.2, and also can be configured
5075 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5078 * Improvements in C++ mangling/demangling.
5080 This release has much better g++ debugging, specifically in name
5081 mangling/demangling, virtual function calls, print virtual table,
5082 call methods, ...etc.
5084 *** Changes in GDB-4.10:
5086 * User visible changes:
5088 Remote debugging using the GDB-specific (`target remote') protocol now
5089 supports the `load' command. This is only useful if you have some
5090 other way of getting the stub to the target system, and you can put it
5091 somewhere in memory where it won't get clobbered by the download.
5093 Filename completion now works.
5095 When run under emacs mode, the "info line" command now causes the
5096 arrow to point to the line specified. Also, "info line" prints
5097 addresses in symbolic form (as well as hex).
5099 All vxworks based targets now support a user settable option, called
5100 vxworks-timeout. This option represents the number of seconds gdb
5101 should wait for responses to rpc's. You might want to use this if
5102 your vxworks target is, perhaps, a slow software simulator or happens
5103 to be on the far side of a thin network line.
5107 This release contains support for using a DEC alpha as a GDB host for
5108 cross debugging. Native alpha debugging is not supported yet.
5111 *** Changes in GDB-4.9:
5115 This is the first GDB release which is accompanied by a matching testsuite.
5116 The testsuite requires installation of dejagnu, which should be available
5117 via ftp from most sites that carry GNU software.
5121 'Cfront' style demangling has had its name changed to 'ARM' style, to
5122 emphasize that it was written from the specifications in the C++ Annotated
5123 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5124 disclaimers, it still generated too much confusion with users attempting to
5125 use gdb with AT&T cfront.
5129 GDB now uses a standard remote interface to a simulator library.
5130 So far, the library contains simulators for the Zilog Z8001/2, the
5131 Hitachi H8/300, H8/500 and Super-H.
5133 * New targets supported
5135 H8/300 simulator h8300-hitachi-hms or h8300hms
5136 H8/500 simulator h8500-hitachi-hms or h8500hms
5137 SH simulator sh-hitachi-hms or sh
5138 Z8000 simulator z8k-zilog-none or z8ksim
5139 IDT MIPS board over serial line mips-idt-ecoff
5141 Cross-debugging to GO32 targets is supported. It requires a custom
5142 version of the i386-stub.c module which is integrated with the
5143 GO32 memory extender.
5145 * New remote protocols
5147 MIPS remote debugging protocol.
5149 * New source languages supported
5151 This version includes preliminary support for Chill, a Pascal like language
5152 used by telecommunications companies. Chill support is also being integrated
5153 into the GNU compiler, but we don't know when it will be publically available.
5156 *** Changes in GDB-4.8:
5158 * HP Precision Architecture supported
5160 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5161 version of this support was available as a set of patches from the
5162 University of Utah. GDB does not support debugging of programs
5163 compiled with the HP compiler, because HP will not document their file
5164 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5165 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5167 Many problems in the preliminary version have been fixed.
5169 * Faster and better demangling
5171 We have improved template demangling and fixed numerous bugs in the GNU style
5172 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5173 character types (wchar_t) are now supported. Demangling of each symbol is now
5174 only done once, and is cached when the symbol table for a file is read in.
5175 This results in a small increase in memory usage for C programs, a moderate
5176 increase in memory usage for C++ programs, and a fantastic speedup in
5179 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5180 from the specifications in the Annotated Reference Manual, which AT&T's
5181 compiler does not actually implement.
5183 * G++ multiple inheritance compiler problem
5185 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5186 inheritance lattices was reworked to properly discover ambiguities. We
5187 recently found an example which causes this new algorithm to fail in a
5188 very subtle way, producing bad debug information for those classes.
5189 The file 'gcc.patch' (in this directory) can be applied to gcc to
5190 circumvent the problem. A future GCC release will contain a complete
5193 The previous G++ debug info problem (mentioned below for the gdb-4.7
5194 release) is fixed in gcc version 2.3.2.
5196 * Improved configure script
5198 The `configure' script will now attempt to guess your system type if
5199 you don't supply a host system type. The old scheme of supplying a
5200 host system triplet is preferable over using this. All the magic is
5201 done in the new `config.guess' script. Examine it for details.
5203 We have also brought our configure script much more in line with the FSF's
5204 version. It now supports the --with-xxx options. In particular,
5205 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5206 The resulting GDB will not be able to read arbitrary object file formats --
5207 only the format ``expected'' to be used on the configured target system.
5208 We hope to make this the default in a future release.
5210 * Documentation improvements
5212 There's new internal documentation on how to modify GDB, and how to
5213 produce clean changes to the code. We implore people to read it
5214 before submitting changes.
5216 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5217 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5218 `info' files are also provided. To build `info' files from scratch,
5219 you will need the latest `makeinfo' release, which will be available in
5220 a future texinfo-X.Y release.
5222 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5223 We're not sure exactly which versions have this problem, but it has
5224 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5225 or better. If that isn't possible, there is a patch in
5226 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5227 around this problem.
5231 GDB now supports array constants that can be used in expressions typed in by
5232 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5233 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5236 The new directory `gdb/sparclite' contains a program that demonstrates
5237 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5239 * New native hosts supported
5241 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5242 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5244 * New targets supported
5246 AMD 29k family via UDI a29k-amd-udi or udi29k
5248 * New file formats supported
5250 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5251 HPUX core files, and SCO 3.2v2 core files.
5255 Attaching to processes now works again; thanks for the many bug reports.
5257 We have also stomped on a bunch of core dumps caused by
5258 printf_filtered("%s") problems.
5260 We eliminated a copyright problem on the rpc and ptrace header files
5261 for VxWorks, which was discovered at the last minute during the 4.7
5262 release. You should now be able to build a VxWorks GDB.
5264 You can now interrupt gdb while an attached process is running. This
5265 will cause the attached process to stop, and give control back to GDB.
5267 We fixed problems caused by using too many file descriptors
5268 for reading symbols from object files and libraries. This was
5269 especially a problem for programs that used many (~100) shared
5272 The `step' command now only enters a subroutine if there is line number
5273 information for the subroutine. Otherwise it acts like the `next'
5274 command. Previously, `step' would enter subroutines if there was
5275 any debugging information about the routine. This avoids problems
5276 when using `cc -g1' on MIPS machines.
5278 * Internal improvements
5280 GDB's internal interfaces have been improved to make it easier to support
5281 debugging of multiple languages in the future.
5283 GDB now uses a common structure for symbol information internally.
5284 Minimal symbols (derived from linkage symbols in object files), partial
5285 symbols (from a quick scan of debug information), and full symbols
5286 contain a common subset of information, making it easier to write
5287 shared code that handles any of them.
5289 * New command line options
5291 We now accept --silent as an alias for --quiet.
5295 The memory-mapped-malloc library is now licensed under the GNU Library
5296 General Public License.
5298 *** Changes in GDB-4.7:
5300 * Host/native/target split
5302 GDB has had some major internal surgery to untangle the support for
5303 hosts and remote targets. Now, when you configure GDB for a remote
5304 target, it will no longer load in all of the support for debugging
5305 local programs on the host. When fully completed and tested, this will
5306 ensure that arbitrary host/target combinations are possible.
5308 The primary conceptual shift is to separate the non-portable code in
5309 GDB into three categories. Host specific code is required any time GDB
5310 is compiled on that host, regardless of the target. Target specific
5311 code relates to the peculiarities of the target, but can be compiled on
5312 any host. Native specific code is everything else: it can only be
5313 built when the host and target are the same system. Child process
5314 handling and core file support are two common `native' examples.
5316 GDB's use of /proc for controlling Unix child processes is now cleaner.
5317 It has been split out into a single module under the `target_ops' vector,
5318 plus two native-dependent functions for each system that uses /proc.
5320 * New hosts supported
5322 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5323 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5324 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5326 * New targets supported
5328 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5329 68030 and CPU32 m68030-*-*, m68332-*-*
5331 * New native hosts supported
5333 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5334 (386bsd is not well tested yet)
5335 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5337 * New file formats supported
5339 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5340 supports reading of `a.out.adobe' object files, which are an a.out
5341 format extended with minimal information about multiple sections.
5345 `show copying' is the same as the old `info copying'.
5346 `show warranty' is the same as `info warrantee'.
5347 These were renamed for consistency. The old commands continue to work.
5349 `info handle' is a new alias for `info signals'.
5351 You can now define pre-command hooks, which attach arbitrary command
5352 scripts to any command. The commands in the hook will be executed
5353 prior to the user's command. You can also create a hook which will be
5354 executed whenever the program stops. See gdb.texinfo.
5358 We now deal with Cfront style name mangling, and can even extract type
5359 info from mangled symbols. GDB can automatically figure out which
5360 symbol mangling style your C++ compiler uses.
5362 Calling of methods and virtual functions has been improved as well.
5366 The crash that occured when debugging Sun Ansi-C compiled binaries is
5367 fixed. This was due to mishandling of the extra N_SO stabs output
5370 We also finally got Ultrix 4.2 running in house, and fixed core file
5371 support, with help from a dozen people on the net.
5373 John M. Farrell discovered that the reason that single-stepping was so
5374 slow on all of the Mips based platforms (primarily SGI and DEC) was
5375 that we were trying to demangle and lookup a symbol used for internal
5376 purposes on every instruction that was being stepped through. Changing
5377 the name of that symbol so that it couldn't be mistaken for a C++
5378 mangled symbol sped things up a great deal.
5380 Rich Pixley sped up symbol lookups in general by getting much smarter
5381 about when C++ symbol mangling is necessary. This should make symbol
5382 completion (TAB on the command line) much faster. It's not as fast as
5383 we'd like, but it's significantly faster than gdb-4.6.
5387 A new user controllable variable 'call_scratch_address' can
5388 specify the location of a scratch area to be used when GDB
5389 calls a function in the target. This is necessary because the
5390 usual method of putting the scratch area on the stack does not work
5391 in systems that have separate instruction and data spaces.
5393 We integrated changes to support the 29k UDI (Universal Debugger
5394 Interface), but discovered at the last minute that we didn't have all
5395 of the appropriate copyright paperwork. We are working with AMD to
5396 resolve this, and hope to have it available soon.
5400 We have sped up the remote serial line protocol, especially for targets
5401 with lots of registers. It now supports a new `expedited status' ('T')
5402 message which can be used in place of the existing 'S' status message.
5403 This allows the remote stub to send only the registers that GDB
5404 needs to make a quick decision about single-stepping or conditional
5405 breakpoints, eliminating the need to fetch the entire register set for
5406 each instruction being stepped through.
5408 The GDB remote serial protocol now implements a write-through cache for
5409 registers, only re-reading the registers if the target has run.
5411 There is also a new remote serial stub for SPARC processors. You can
5412 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5413 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5414 processor with a serial port.
5418 Configure.in files have become much easier to read and modify. A new
5419 `table driven' format makes it more obvious what configurations are
5420 supported, and what files each one uses.
5424 There is a new opcodes library which will eventually contain all of the
5425 disassembly routines and opcode tables. At present, it only contains
5426 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5427 disassembler (binutils/objdump) to share these routines.
5429 The libiberty library is now copylefted under the GNU Library General
5430 Public License. This allows more liberal use, and was done so libg++
5431 can use it. This makes no difference to GDB, since the Library License
5432 grants all the rights from the General Public License.
5436 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5437 reference to the stabs symbol info used by the debugger. It is (as far
5438 as we know) the only published document on this fascinating topic. We
5439 encourage you to read it, compare it to the stabs information on your
5440 system, and send improvements on the document in general (to
5441 bug-gdb@prep.ai.mit.edu).
5443 And, of course, many bugs have been fixed.
5446 *** Changes in GDB-4.6:
5448 * Better support for C++ function names
5450 GDB now accepts as input the "demangled form" of C++ overloaded function
5451 names and member function names, and can do command completion on such names
5452 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5453 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5454 Make use of command completion, it is your friend.
5456 GDB also now accepts a variety of C++ mangled symbol formats. They are
5457 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5458 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5459 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5460 for the list of formats.
5462 * G++ symbol mangling problem
5464 Recent versions of gcc have a bug in how they emit debugging information for
5465 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5466 directory) can be applied to gcc to fix the problem. Alternatively, if you
5467 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5468 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5469 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5472 * New 'maintenance' command
5474 All of the commands related to hacking GDB internals have been moved out of
5475 the main command set, and now live behind the 'maintenance' command. This
5476 can also be abbreviated as 'mt'. The following changes were made:
5478 dump-me -> maintenance dump-me
5479 info all-breakpoints -> maintenance info breakpoints
5480 printmsyms -> maintenance print msyms
5481 printobjfiles -> maintenance print objfiles
5482 printpsyms -> maintenance print psymbols
5483 printsyms -> maintenance print symbols
5485 The following commands are new:
5487 maintenance demangle Call internal GDB demangler routine to
5488 demangle a C++ link name and prints the result.
5489 maintenance print type Print a type chain for a given symbol
5491 * Change to .gdbinit file processing
5493 We now read the $HOME/.gdbinit file before processing the argv arguments
5494 (e.g. reading symbol files or core files). This allows global parameters to
5495 be set, which will apply during the symbol reading. The ./.gdbinit is still
5496 read after argv processing.
5498 * New hosts supported
5500 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5502 GNU/Linux support i386-unknown-linux or linux
5504 We are also including code to support the HP/PA running BSD and HPUX. This
5505 is almost guaranteed not to work, as we didn't have time to test or build it
5506 for this release. We are including it so that the more adventurous (or
5507 masochistic) of you can play with it. We also had major problems with the
5508 fact that the compiler that we got from HP doesn't support the -g option.
5511 * New targets supported
5513 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5515 * More smarts about finding #include files
5517 GDB now remembers the compilation directory for all include files, and for
5518 all files from which C is generated (like yacc and lex sources). This
5519 greatly improves GDB's ability to find yacc/lex sources, and include files,
5520 especially if you are debugging your program from a directory different from
5521 the one that contains your sources.
5523 We also fixed a bug which caused difficulty with listing and setting
5524 breakpoints in include files which contain C code. (In the past, you had to
5525 try twice in order to list an include file that you hadn't looked at before.)
5527 * Interesting infernals change
5529 GDB now deals with arbitrary numbers of sections, where the symbols for each
5530 section must be relocated relative to that section's landing place in the
5531 target's address space. This work was needed to support ELF with embedded
5532 stabs used by Solaris-2.0.
5534 * Bug fixes (of course!)
5536 There have been loads of fixes for the following things:
5537 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5538 i960, stabs, DOS(GO32), procfs, etc...
5540 See the ChangeLog for details.
5542 *** Changes in GDB-4.5:
5544 * New machines supported (host and target)
5546 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5548 SGI Irix-4.x mips-sgi-irix4 or iris4
5550 * New malloc package
5552 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5553 Mmalloc is capable of handling mutiple heaps of memory. It is also
5554 capable of saving a heap to a file, and then mapping it back in later.
5555 This can be used to greatly speedup the startup of GDB by using a
5556 pre-parsed symbol table which lives in a mmalloc managed heap. For
5557 more details, please read mmalloc/mmalloc.texi.
5561 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5562 'help info proc' for details.
5564 * MIPS ecoff symbol table format
5566 The code that reads MIPS symbol table format is now supported on all hosts.
5567 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5570 * File name changes for MS-DOS
5572 Many files in the config directories have been renamed to make it easier to
5573 support GDB on MS-DOSe systems (which have very restrictive file name
5574 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5575 environment) is close to working but has some remaining problems. Note
5576 that debugging of DOS programs is not supported, due to limitations
5577 in the ``operating system'', but it can be used to host cross-debugging.
5579 * Cross byte order fixes
5581 Many fixes have been made to support cross debugging of Sparc and MIPS
5582 targets from hosts whose byte order differs.
5584 * New -mapped and -readnow options
5586 If memory-mapped files are available on your system through the 'mmap'
5587 system call, you can use the -mapped option on the `file' or
5588 `symbol-file' commands to cause GDB to write the symbols from your
5589 program into a reusable file. If the program you are debugging is
5590 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5591 Future GDB debugging sessions will notice the presence of this file,
5592 and will quickly map in symbol information from it, rather than reading
5593 the symbol table from the executable program. Using the '-mapped'
5594 option in a GDB `file' or `symbol-file' command has the same effect as
5595 starting GDB with the '-mapped' command-line option.
5597 You can cause GDB to read the entire symbol table immediately by using
5598 the '-readnow' option with any of the commands that load symbol table
5599 information (or on the GDB command line). This makes the command
5600 slower, but makes future operations faster.
5602 The -mapped and -readnow options are typically combined in order to
5603 build a `fred.syms' file that contains complete symbol information.
5604 A simple GDB invocation to do nothing but build a `.syms' file for future
5607 gdb -batch -nx -mapped -readnow programname
5609 The `.syms' file is specific to the host machine on which GDB is run.
5610 It holds an exact image of GDB's internal symbol table. It cannot be
5611 shared across multiple host platforms.
5613 * longjmp() handling
5615 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5616 siglongjmp() without losing control. This feature has not yet been ported to
5617 all systems. It currently works on many 386 platforms, all MIPS-based
5618 platforms (SGI, DECstation, etc), and Sun3/4.
5622 Preliminary work has been put in to support the new Solaris OS from Sun. At
5623 this time, it can control and debug processes, but it is not capable of
5628 As always, many many bug fixes. The major areas were with g++, and mipsread.
5629 People using the MIPS-based platforms should experience fewer mysterious
5630 crashes and trashed symbol tables.
5632 *** Changes in GDB-4.4:
5634 * New machines supported (host and target)
5636 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5638 BSD Reno on Vax vax-dec-bsd
5639 Ultrix on Vax vax-dec-ultrix
5641 * New machines supported (target)
5643 AMD 29000 embedded, using EBMON a29k-none-none
5647 GDB continues to improve its handling of C++. `References' work better.
5648 The demangler has also been improved, and now deals with symbols mangled as
5649 per the Annotated C++ Reference Guide.
5651 GDB also now handles `stabs' symbol information embedded in MIPS
5652 `ecoff' symbol tables. Since the ecoff format was not easily
5653 extensible to handle new languages such as C++, this appeared to be a
5654 good way to put C++ debugging info into MIPS binaries. This option
5655 will be supported in the GNU C compiler, version 2, when it is
5658 * New features for SVR4
5660 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5661 shared libraries. Debugging dynamically linked programs should present
5662 only minor differences from debugging statically linked programs.
5664 The `info proc' command will print out information about any process
5665 on an SVR4 system (including the one you are debugging). At the moment,
5666 it prints the address mappings of the process.
5668 If you bring up GDB on another SVR4 system, please send mail to
5669 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5671 * Better dynamic linking support in SunOS
5673 Reading symbols from shared libraries which contain debugging symbols
5674 now works properly. However, there remain issues such as automatic
5675 skipping of `transfer vector' code during function calls, which
5676 make it harder to debug code in a shared library, than to debug the
5677 same code linked statically.
5681 GDB is now using the latest `getopt' routines from the FSF. This
5682 version accepts the -- prefix for options with long names. GDB will
5683 continue to accept the old forms (-option and +option) as well.
5684 Various single letter abbreviations for options have been explicity
5685 added to the option table so that they won't get overshadowed in the
5686 future by other options that begin with the same letter.
5690 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5691 Many assorted bugs have been handled. Many more remain to be handled.
5692 See the various ChangeLog files (primarily in gdb and bfd) for details.
5695 *** Changes in GDB-4.3:
5697 * New machines supported (host and target)
5699 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5700 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5701 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5703 * Almost SCO Unix support
5705 We had hoped to support:
5706 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5707 (except for core file support), but we discovered very late in the release
5708 that it has problems with process groups that render gdb unusable. Sorry
5709 about that. I encourage people to fix it and post the fixes.
5711 * Preliminary ELF and DWARF support
5713 GDB can read ELF object files on System V Release 4, and can handle
5714 debugging records for C, in DWARF format, in ELF files. This support
5715 is preliminary. If you bring up GDB on another SVR4 system, please
5716 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5721 GDB now uses the latest `readline' library. One user-visible change
5722 is that two tabs will list possible command completions, which previously
5723 required typing M-? (meta-question mark, or ESC ?).
5727 The `stepi' bug that many of you noticed has been squashed.
5728 Many bugs in C++ have been handled. Many more remain to be handled.
5729 See the various ChangeLog files (primarily in gdb and bfd) for details.
5731 * State of the MIPS world (in case you wondered):
5733 GDB can understand the symbol tables emitted by the compilers
5734 supplied by most vendors of MIPS-based machines, including DEC. These
5735 symbol tables are in a format that essentially nobody else uses.
5737 Some versions of gcc come with an assembler post-processor called
5738 mips-tfile. This program is required if you want to do source-level
5739 debugging of gcc-compiled programs. I believe FSF does not ship
5740 mips-tfile with gcc version 1, but it will eventually come with gcc
5743 Debugging of g++ output remains a problem. g++ version 1.xx does not
5744 really support it at all. (If you're lucky, you should be able to get
5745 line numbers and stack traces to work, but no parameters or local
5746 variables.) With some work it should be possible to improve the
5749 When gcc version 2 is released, you will have somewhat better luck.
5750 However, even then you will get confusing results for inheritance and
5753 We will eventually provide full debugging of g++ output on
5754 DECstations. This will probably involve some kind of stabs-in-ecoff
5755 encapulation, but the details have not been worked out yet.
5758 *** Changes in GDB-4.2:
5760 * Improved configuration
5762 Only one copy of `configure' exists now, and it is not self-modifying.
5763 Porting BFD is simpler.
5767 The `step' and `next' commands now only stop at the first instruction
5768 of a source line. This prevents the multiple stops that used to occur
5769 in switch statements, for-loops, etc. `Step' continues to stop if a
5770 function that has debugging information is called within the line.
5774 Lots of small bugs fixed. More remain.
5776 * New host supported (not target)
5778 Intel 386 PC clone running Mach i386-none-mach
5781 *** Changes in GDB-4.1:
5783 * Multiple source language support
5785 GDB now has internal scaffolding to handle several source languages.
5786 It determines the type of each source file from its filename extension,
5787 and will switch expression parsing and number formatting to match the
5788 language of the function in the currently selected stack frame.
5789 You can also specifically set the language to be used, with
5790 `set language c' or `set language modula-2'.
5794 GDB now has preliminary support for the GNU Modula-2 compiler,
5795 currently under development at the State University of New York at
5796 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5797 continue through the fall of 1991 and into 1992.
5799 Other Modula-2 compilers are currently not supported, and attempting to
5800 debug programs compiled with them will likely result in an error as the
5801 symbol table is read. Feel free to work on it, though!
5803 There are hooks in GDB for strict type checking and range checking,
5804 in the `Modula-2 philosophy', but they do not currently work.
5808 GDB can now write to executable and core files (e.g. patch
5809 a variable's value). You must turn this switch on, specify
5810 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5811 by assigning a new value to a variable. Modifications take
5814 * Automatic SunOS shared library reading
5816 When you run your program, GDB automatically determines where its
5817 shared libraries (if any) have been loaded, and reads their symbols.
5818 The `share' command is no longer needed. This also works when
5819 examining core files.
5823 You can specify the number of lines that the `list' command shows.
5826 * New machines supported (host and target)
5828 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5829 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5830 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5832 * New hosts supported (not targets)
5834 IBM RT/PC: romp-ibm-aix or rtpc
5836 * New targets supported (not hosts)
5838 AMD 29000 embedded with COFF a29k-none-coff
5839 AMD 29000 embedded with a.out a29k-none-aout
5840 Ultracomputer remote kernel debug a29k-nyu-kern
5842 * New remote interfaces
5848 *** Changes in GDB-4.0:
5852 Wide output is wrapped at good places to make the output more readable.
5854 Gdb now supports cross-debugging from a host machine of one type to a
5855 target machine of another type. Communication with the target system
5856 is over serial lines. The ``target'' command handles connecting to the
5857 remote system; the ``load'' command will download a program into the
5858 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5859 also supports debugging of realtime processes running under VxWorks,
5860 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5861 stub on the target system.
5863 New CPUs supported include the AMD 29000 and Intel 960.
5865 GDB now reads object files and symbol tables via a ``binary file''
5866 library, which allows a single copy of GDB to debug programs of multiple
5867 object file types such as a.out and coff.
5869 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5870 refcard.dvi and refcard.ps are available to format it).
5873 * Control-Variable user interface simplified
5875 All variables that control the operation of the debugger can be set
5876 by the ``set'' command, and displayed by the ``show'' command.
5878 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5879 ``Show prompt'' produces the response:
5880 Gdb's prompt is new-gdb=>.
5882 What follows are the NEW set commands. The command ``help set'' will
5883 print a complete list of old and new set commands. ``help set FOO''
5884 will give a longer description of the variable FOO. ``show'' will show
5885 all of the variable descriptions and their current settings.
5887 confirm on/off: Enables warning questions for operations that are
5888 hard to recover from, e.g. rerunning the program while
5889 it is already running. Default is ON.
5891 editing on/off: Enables EMACS style command line editing
5892 of input. Previous lines can be recalled with
5893 control-P, the current line can be edited with control-B,
5894 you can search for commands with control-R, etc.
5897 history filename NAME: NAME is where the gdb command history
5898 will be stored. The default is .gdb_history,
5899 or the value of the environment variable
5902 history size N: The size, in commands, of the command history. The
5903 default is 256, or the value of the environment variable
5906 history save on/off: If this value is set to ON, the history file will
5907 be saved after exiting gdb. If set to OFF, the
5908 file will not be saved. The default is OFF.
5910 history expansion on/off: If this value is set to ON, then csh-like
5911 history expansion will be performed on
5912 command line input. The default is OFF.
5914 radix N: Sets the default radix for input and output. It can be set
5915 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5916 in the current radix, so "set radix 10" is always a no-op.
5918 height N: This integer value is the number of lines on a page. Default
5919 is 24, the current `stty rows'' setting, or the ``li#''
5920 setting from the termcap entry matching the environment
5923 width N: This integer value is the number of characters on a line.
5924 Default is 80, the current `stty cols'' setting, or the ``co#''
5925 setting from the termcap entry matching the environment
5928 Note: ``set screensize'' is obsolete. Use ``set height'' and
5929 ``set width'' instead.
5931 print address on/off: Print memory addresses in various command displays,
5932 such as stack traces and structure values. Gdb looks
5933 more ``symbolic'' if you turn this off; it looks more
5934 ``machine level'' with it on. Default is ON.
5936 print array on/off: Prettyprint arrays. New convenient format! Default
5939 print demangle on/off: Print C++ symbols in "source" form if on,
5942 print asm-demangle on/off: Same, for assembler level printouts
5945 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5948 * Support for Epoch Environment.
5950 The epoch environment is a version of Emacs v18 with windowing. One
5951 new command, ``inspect'', is identical to ``print'', except that if you
5952 are running in the epoch environment, the value is printed in its own
5956 * Support for Shared Libraries
5958 GDB can now debug programs and core files that use SunOS shared libraries.
5959 Symbols from a shared library cannot be referenced
5960 before the shared library has been linked with the program (this
5961 happens after you type ``run'' and before the function main() is entered).
5962 At any time after this linking (including when examining core files
5963 from dynamically linked programs), gdb reads the symbols from each
5964 shared library when you type the ``sharedlibrary'' command.
5965 It can be abbreviated ``share''.
5967 sharedlibrary REGEXP: Load shared object library symbols for files
5968 matching a unix regular expression. No argument
5969 indicates to load symbols for all shared libraries.
5971 info sharedlibrary: Status of loaded shared libraries.
5976 A watchpoint stops execution of a program whenever the value of an
5977 expression changes. Checking for this slows down execution
5978 tremendously whenever you are in the scope of the expression, but is
5979 quite useful for catching tough ``bit-spreader'' or pointer misuse
5980 problems. Some machines such as the 386 have hardware for doing this
5981 more quickly, and future versions of gdb will use this hardware.
5983 watch EXP: Set a watchpoint (breakpoint) for an expression.
5985 info watchpoints: Information about your watchpoints.
5987 delete N: Deletes watchpoint number N (same as breakpoints).
5988 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5989 enable N: Re-enables watchpoint number N (same as breakpoints).
5992 * C++ multiple inheritance
5994 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5997 * C++ exception handling
5999 Gdb now supports limited C++ exception handling. Besides the existing
6000 ability to breakpoint on an exception handler, gdb can breakpoint on
6001 the raising of an exception (before the stack is peeled back to the
6004 catch FOO: If there is a FOO exception handler in the dynamic scope,
6005 set a breakpoint to catch exceptions which may be raised there.
6006 Multiple exceptions (``catch foo bar baz'') may be caught.
6008 info catch: Lists all exceptions which may be caught in the
6009 current stack frame.
6012 * Minor command changes
6014 The command ``call func (arg, arg, ...)'' now acts like the print
6015 command, except it does not print or save a value if the function's result
6016 is void. This is similar to dbx usage.
6018 The ``up'' and ``down'' commands now always print the frame they end up
6019 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6020 frames without printing.
6022 * New directory command
6024 'dir' now adds directories to the FRONT of the source search path.
6025 The path starts off empty. Source files that contain debug information
6026 about the directory in which they were compiled can be found even
6027 with an empty path; Sun CC and GCC include this information. If GDB can't
6028 find your source file in the current directory, type "dir .".
6030 * Configuring GDB for compilation
6032 For normal use, type ``./configure host''. See README or gdb.texinfo
6035 GDB now handles cross debugging. If you are remotely debugging between
6036 two different machines, type ``./configure host -target=targ''.
6037 Host is the machine where GDB will run; targ is the machine
6038 where the program that you are debugging will run.
projects / external / binutils.git / blob