1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.9
7 * GDB now honors the content of the file /proc/PID/coredump_filter
8 (PID is the process ID) on GNU/Linux systems. This file can be used
9 to specify the types of memory mappings that will be included in a
10 corefile. For more information, please refer to the manual page of
11 "core(5)". GDB also has a new command: "set use-coredump-filter
12 on|off". It allows to set whether GDB will read the content of the
13 /proc/PID/coredump_filter file when generating a corefile.
15 * The "info os" command on GNU/Linux can now display information on
17 "info os cpus" Listing of all cpus/cores on the system
19 * GDB has two new commands: "set serial parity odd|even|none" and
20 "show serial parity". These allows to set or show parity for the
23 * The "info source" command now displays the producer string if it was
24 present in the debug info. This typically includes the compiler version
25 and may include things like its command line arguments.
27 * Directory names supplied to the "set sysroot" commands may be
28 prefixed with "target:" to tell GDB to access shared libraries from
29 the target system, be it local or remote. This replaces the prefix
30 "remote:". The default sysroot has been changed from "" to
31 "target:". "remote:" is automatically converted to "target:" for
32 backward compatibility.
34 * The system root specified by "set sysroot" will be prepended to the
35 filename of the main executable (if reported to GDB as absolute by
36 the operating system) when starting processes remotely, and when
37 attaching to already-running local or remote processes.
41 ** gdb.Objfile objects have a new attribute "username",
42 which is the name of the objfile as specified by the user,
43 without, for example, resolving symlinks.
44 ** You can now write frame unwinders in Python.
48 maint print symbol-cache
49 Print the contents of the symbol cache.
51 maint print symbol-cache-statistics
52 Print statistics of symbol cache usage.
54 maint flush-symbol-cache
55 Flush the contents of the symbol cache.
59 Start branch trace recording using Branch Trace Store (BTS) format.
65 Set the maximum number of candidates to be considered during
66 completion. The default value is 200. This limit allows GDB
67 to avoid generating large completion lists, the computation of
68 which can cause the debugger to become temporarily unresponsive.
70 maint set symbol-cache-size
71 maint show symbol-cache-size
72 Control the size of the symbol cache.
74 set|show record btrace bts buffer-size
75 Set and show the size of the ring buffer used for branch tracing in
77 The obtained size may differ from the requested size. Use "info
78 record" to see the obtained buffer size.
80 * The command 'thread apply all' can now support new option '-ascending'
81 to call its specified command for all threads in ascending order.
83 * Python/Guile scripting
85 ** GDB now supports auto-loading of Python/Guile scripts contained in the
86 special section named `.debug_gdb_scripts'.
90 qXfer:btrace-conf:read
91 Return the branch trace configuration for the current thread.
94 Set the requested ring buffer size for branch tracing in BTS format.
97 Indicates a memory breakpoint instruction was executed, irrespective
98 of whether it was GDB that planted the breakpoint or the breakpoint
99 is hardcoded in the program. This is required for correct non-stop
103 Indicates the target stopped for a hardware breakpoint. This is
104 required for correct non-stop mode operation.
107 Return information about files on the remote system.
109 * The info record command now shows the recording format and the
110 branch tracing configuration for the current thread when using
111 the btrace record target.
112 For the BTS format, it shows the ring buffer size.
114 * GDB now has support for DTrace USDT (Userland Static Defined
115 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
117 * GDB now supports access to vector registers on S/390 GNU/Linux
120 * Removed command line options
122 -xdb HP-UX XDB compatibility mode.
124 * Removed targets and native configurations
126 HP/PA running HP-UX hppa*-*-hpux*
127 Itanium running HP-UX ia64-*-hpux*
129 *** Changes in GDB 7.9
131 * GDB now supports hardware watchpoints on x86 GNU Hurd.
135 ** You can now access frame registers from Python scripts.
136 ** New attribute 'producer' for gdb.Symtab objects.
137 ** gdb.Objfile objects have a new attribute "progspace",
138 which is the gdb.Progspace object of the containing program space.
139 ** gdb.Objfile objects have a new attribute "owner".
140 ** gdb.Objfile objects have a new attribute "build_id",
141 which is the build ID generated when the file was built.
142 ** gdb.Objfile objects have a new method "add_separate_debug_file".
143 ** A new event "gdb.clear_objfiles" has been added, triggered when
144 selecting a new file to debug.
145 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
146 ** New function gdb.lookup_objfile.
148 New events which are triggered when GDB modifies the state of the
151 ** gdb.events.inferior_call_pre: Function call is about to be made.
152 ** gdb.events.inferior_call_post: Function call has just been made.
153 ** gdb.events.memory_changed: A memory location has been altered.
154 ** gdb.events.register_changed: A register has been altered.
156 * New Python-based convenience functions:
158 ** $_caller_is(name [, number_of_frames])
159 ** $_caller_matches(regexp [, number_of_frames])
160 ** $_any_caller_is(name [, number_of_frames])
161 ** $_any_caller_matches(regexp [, number_of_frames])
163 * GDB now supports the compilation and injection of source code into
164 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
165 to compile the source code to object code, and if successful, inject
166 and execute that code within the current context of the inferior.
167 Currently the C language is supported. The commands used to
168 interface with this new feature are:
170 compile code [-raw|-r] [--] [source code]
171 compile file [-raw|-r] filename
175 demangle [-l language] [--] name
176 Demangle "name" in the specified language, or the current language
177 if elided. This command is renamed from the "maint demangle" command.
178 The latter is kept as a no-op to avoid "maint demangle" being interpreted
179 as "maint demangler-warning".
181 queue-signal signal-name-or-number
182 Queue a signal to be delivered to the thread when it is resumed.
184 add-auto-load-scripts-directory directory
185 Add entries to the list of directories from which to load auto-loaded
188 maint print user-registers
189 List all currently available "user" registers.
191 compile code [-r|-raw] [--] [source code]
192 Compile, inject, and execute in the inferior the executable object
193 code produced by compiling the provided source code.
195 compile file [-r|-raw] filename
196 Compile and inject into the inferior the executable object code
197 produced by compiling the source code stored in the filename
200 * On resume, GDB now always passes the signal the program had stopped
201 for to the thread the signal was sent to, even if the user changed
202 threads before resuming. Previously GDB would often (but not
203 always) deliver the signal to the thread that happens to be current
206 * Conversely, the "signal" command now consistently delivers the
207 requested signal to the current thread. GDB now asks for
208 confirmation if the program had stopped for a signal and the user
209 switched threads meanwhile.
211 * "breakpoint always-inserted" modes "off" and "auto" merged.
213 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
214 won't remove breakpoints from the target until all threads stop,
215 even in non-stop mode. The "auto" mode has been removed, and "off"
216 is now the default mode.
220 set debug symbol-lookup
221 show debug symbol-lookup
222 Control display of debugging info regarding symbol lookup.
226 ** The -list-thread-groups command outputs an exit-code field for
227 inferiors that have exited.
231 MIPS SDE mips*-sde*-elf*
235 Support for these obsolete configurations has been removed.
237 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
238 SGI Irix-5.x mips-*-irix5*
239 SGI Irix-6.x mips-*-irix6*
240 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
241 VAX running Ultrix vax-*-ultrix*
243 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
244 and "assf"), have been removed. Use the "sharedlibrary" command, or
245 its alias "share", instead.
247 *** Changes in GDB 7.8
249 * New command line options
252 This is an alias for the --data-directory option.
254 * GDB supports printing and modifying of variable length automatic arrays
255 as specified in ISO C99.
257 * The ARM simulator now supports instruction level tracing
258 with or without disassembly.
262 GDB now has support for scripting using Guile. Whether this is
263 available is determined at configure time.
264 Guile version 2.0 or greater is required.
265 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
267 * New commands (for set/show, see "New options" below)
271 Invoke CODE by passing it to the Guile interpreter.
275 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
277 info auto-load guile-scripts [regexp]
278 Print the list of automatically loaded Guile scripts.
280 * The source command is now capable of sourcing Guile scripts.
281 This feature is dependent on the debugger being built with Guile support.
285 set print symbol-loading (off|brief|full)
286 show print symbol-loading
287 Control whether to print informational messages when loading symbol
288 information for a file. The default is "full", but when debugging
289 programs with large numbers of shared libraries the amount of output
292 set guile print-stack (none|message|full)
293 show guile print-stack
294 Show a stack trace when an error is encountered in a Guile script.
296 set auto-load guile-scripts (on|off)
297 show auto-load guile-scripts
298 Control auto-loading of Guile script files.
300 maint ada set ignore-descriptive-types (on|off)
301 maint ada show ignore-descriptive-types
302 Control whether the debugger should ignore descriptive types in Ada
303 programs. The default is not to ignore the descriptive types. See
304 the user manual for more details on descriptive types and the intended
305 usage of this option.
307 set auto-connect-native-target
309 Control whether GDB is allowed to automatically connect to the
310 native target for the run, attach, etc. commands when not connected
311 to any target yet. See also "target native" below.
313 set record btrace replay-memory-access (read-only|read-write)
314 show record btrace replay-memory-access
315 Control what memory accesses are allowed during replay.
317 maint set target-async (on|off)
318 maint show target-async
319 This controls whether GDB targets operate in synchronous or
320 asynchronous mode. Normally the default is asynchronous, if it is
321 available; but this can be changed to more easily debug problems
322 occurring only in synchronous mode.
324 set mi-async (on|off)
326 Control whether MI asynchronous mode is preferred. This supersedes
327 "set target-async" of previous GDB versions.
329 * "set target-async" is deprecated as a CLI option and is now an alias
330 for "set mi-async" (only puts MI into async mode).
332 * Background execution commands (e.g., "c&", "s&", etc.) are now
333 possible ``out of the box'' if the target supports them. Previously
334 the user would need to explicitly enable the possibility with the
335 "set target-async on" command.
337 * New features in the GDB remote stub, GDBserver
339 ** New option --debug-format=option1[,option2,...] allows one to add
340 additional text to each output. At present only timestamps
341 are supported: --debug-format=timestamps.
342 Timestamps can also be turned on with the
343 "monitor set debug-format timestamps" command from GDB.
345 * The 'record instruction-history' command now starts counting instructions
346 at one. This also affects the instruction ranges reported by the
347 'record function-call-history' command when given the /i modifier.
349 * The command 'record function-call-history' supports a new modifier '/c' to
350 indent the function names based on their call stack depth.
351 The fields for the '/i' and '/l' modifier have been reordered.
352 The source line range is now prefixed with 'at'.
353 The instruction range is now prefixed with 'inst'.
354 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
355 "record instruction-history" and "list" commands.
357 * The ranges given as arguments to the 'record function-call-history' and
358 'record instruction-history' commands are now inclusive.
360 * The btrace record target now supports the 'record goto' command.
361 For locations inside the execution trace, the back trace is computed
362 based on the information stored in the execution trace.
364 * The btrace record target supports limited reverse execution and replay.
365 The target does not record data and therefore does not allow reading
368 * The "catch syscall" command now works on s390*-linux* targets.
370 * The "compare-sections" command is no longer specific to target
371 remote. It now works with all targets.
373 * All native targets are now consistently called "native".
374 Consequently, the "target child", "target GNU", "target djgpp",
375 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
376 commands have been replaced with "target native". The QNX/NTO port
377 leaves the "procfs" target in place and adds a "native" target for
378 consistency with other ports. The impact on users should be minimal
379 as these commands previously either throwed an error, or were
380 no-ops. The target's name is visible in the output of the following
381 commands: "help target", "info target", "info files", "maint print
384 * The "target native" command now connects to the native target. This
385 can be used to launch native programs even when "set
386 auto-connect-native-target" is set to off.
388 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
390 * Support for Intel(R) AVX-512 registers on GNU/Linux.
391 Support displaying and modifying Intel(R) AVX-512 registers
392 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
396 qXfer:btrace:read's annex
397 The qXfer:btrace:read packet supports a new annex 'delta' to read
398 branch trace incrementally.
402 ** Valid Python operations on gdb.Value objects representing
403 structs/classes invoke the corresponding overloaded operators if
405 ** New `Xmethods' feature in the Python API. Xmethods are
406 additional methods or replacements for existing methods of a C++
407 class. This feature is useful for those cases where a method
408 defined in C++ source code could be inlined or optimized out by
409 the compiler, making it unavailable to GDB.
412 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
414 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
415 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
416 its alias "share", instead.
418 * The commands "set remotebaud" and "show remotebaud" are no longer
419 supported. Use "set serial baud" and "show serial baud" (respectively)
424 ** A new option "-gdb-set mi-async" replaces "-gdb-set
425 target-async". The latter is left as a deprecated alias of the
426 former for backward compatibility. If the target supports it,
427 CLI background execution commands are now always possible by
428 default, independently of whether the frontend stated a
429 preference for asynchronous execution with "-gdb-set mi-async".
430 Previously "-gdb-set target-async off" affected both MI execution
431 commands and CLI execution commands.
433 *** Changes in GDB 7.7
435 * Improved support for process record-replay and reverse debugging on
436 arm*-linux* targets. Support for thumb32 and syscall instruction
437 recording has been added.
439 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
441 * GDB now supports Fission DWP file format version 2.
442 http://gcc.gnu.org/wiki/DebugFission
444 * New convenience function "$_isvoid", to check whether an expression
445 is void. A void expression is an expression where the type of the
446 result is "void". For example, some convenience variables may be
447 "void" when evaluated (e.g., "$_exitcode" before the execution of
448 the program being debugged; or an undefined convenience variable).
449 Another example, when calling a function whose return type is
452 * The "maintenance print objfiles" command now takes an optional regexp.
454 * The "catch syscall" command now works on arm*-linux* targets.
456 * GDB now consistently shows "<not saved>" when printing values of
457 registers the debug info indicates have not been saved in the frame
458 and there's nowhere to retrieve them from
459 (callee-saved/call-clobbered registers):
464 (gdb) info registers rax
467 Before, the former would print "<optimized out>", and the latter
468 "*value not available*".
470 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
475 ** Frame filters and frame decorators have been added.
476 ** Temporary breakpoints are now supported.
477 ** Line tables representation has been added.
478 ** New attribute 'parent_type' for gdb.Field objects.
479 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
480 ** New attribute 'name' for gdb.Type objects.
484 Nios II ELF nios2*-*-elf
485 Nios II GNU/Linux nios2*-*-linux
486 Texas Instruments MSP430 msp430*-*-elf
488 * Removed native configurations
490 Support for these a.out NetBSD and OpenBSD obsolete configurations has
491 been removed. ELF variants of these configurations are kept supported.
493 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
494 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
495 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
496 i[34567]86-*-openbsd3.[0-3]
497 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
498 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
499 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
503 Like "catch throw", but catches a re-thrown exception.
505 Renamed from old "maint check-symtabs".
507 Perform consistency checks on symtabs.
509 Expand symtabs matching an optional regexp.
512 Display the details of GDB configure-time options.
514 maint set|show per-command
515 maint set|show per-command space
516 maint set|show per-command time
517 maint set|show per-command symtab
518 Enable display of per-command gdb resource usage.
520 remove-symbol-file FILENAME
521 remove-symbol-file -a ADDRESS
522 Remove a symbol file added via add-symbol-file. The file to remove
523 can be identified by its filename or by an address that lies within
524 the boundaries of this symbol file in memory.
527 info exceptions REGEXP
528 Display the list of Ada exceptions defined in the program being
529 debugged. If provided, only the exceptions whose names match REGEXP
534 set debug symfile off|on
536 Control display of debugging info regarding reading symbol files and
537 symbol tables within those files
539 set print raw frame-arguments
540 show print raw frame-arguments
541 Set/show whether to print frame arguments in raw mode,
542 disregarding any defined pretty-printers.
544 set remote trace-status-packet
545 show remote trace-status-packet
546 Set/show the use of remote protocol qTStatus packet.
550 Control display of debugging messages related to Nios II targets.
554 Control whether target-assisted range stepping is enabled.
556 set startup-with-shell
557 show startup-with-shell
558 Specifies whether Unix child processes are started via a shell or
563 Use the target memory cache for accesses to the code segment. This
564 improves performance of remote debugging (particularly disassembly).
566 * You can now use a literal value 'unlimited' for options that
567 interpret 0 or -1 as meaning "unlimited". E.g., "set
568 trace-buffer-size unlimited" is now an alias for "set
569 trace-buffer-size -1" and "set height unlimited" is now an alias for
572 * The "set debug symtab-create" debugging option of GDB has been changed to
573 accept a verbosity level. 0 means "off", 1 provides basic debugging
574 output, and values of 2 or greater provides more verbose output.
576 * New command-line options
578 Display the details of GDB configure-time options.
580 * The command 'tsave' can now support new option '-ctf' to save trace
581 buffer in Common Trace Format.
583 * Newly installed $prefix/bin/gcore acts as a shell interface for the
586 * GDB now implements the the C++ 'typeid' operator.
588 * The new convenience variable $_exception holds the exception being
589 thrown or caught at an exception-related catchpoint.
591 * The exception-related catchpoints, like "catch throw", now accept a
592 regular expression which can be used to filter exceptions by type.
594 * The new convenience variable $_exitsignal is automatically set to
595 the terminating signal number when the program being debugged dies
596 due to an uncaught signal.
600 ** All MI commands now accept an optional "--language" option.
601 Support for this feature can be verified by using the "-list-features"
602 command, which should contain "language-option".
604 ** The new command -info-gdb-mi-command allows the user to determine
605 whether a GDB/MI command is supported or not.
607 ** The "^error" result record returned when trying to execute an undefined
608 GDB/MI command now provides a variable named "code" whose content is the
609 "undefined-command" error code. Support for this feature can be verified
610 by using the "-list-features" command, which should contain
611 "undefined-command-error-code".
613 ** The -trace-save MI command can optionally save trace buffer in Common
616 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
618 ** The command -data-list-register-values now accepts an optional
619 "--skip-unavailable" option. When used, only the available registers
622 ** The new command -trace-frame-collected dumps collected variables,
623 computed expressions, tvars, memory and registers in a traceframe.
625 ** The commands -stack-list-locals, -stack-list-arguments and
626 -stack-list-variables now accept an option "--skip-unavailable".
627 When used, only the available locals or arguments are displayed.
629 ** The -exec-run command now accepts an optional "--start" option.
630 When used, the command follows the same semantics as the "start"
631 command, stopping the program's execution at the start of its
632 main subprogram. Support for this feature can be verified using
633 the "-list-features" command, which should contain
634 "exec-run-start-option".
636 ** The new commands -catch-assert and -catch-exceptions insert
637 catchpoints stopping the program when Ada exceptions are raised.
639 ** The new command -info-ada-exceptions provides the equivalent of
640 the new "info exceptions" command.
642 * New system-wide configuration scripts
643 A GDB installation now provides scripts suitable for use as system-wide
644 configuration scripts for the following systems:
648 * GDB now supports target-assigned range stepping with remote targets.
649 This improves the performance of stepping source lines by reducing
650 the number of control packets from/to GDB. See "New remote packets"
653 * GDB now understands the element 'tvar' in the XML traceframe info.
654 It has the id of the collected trace state variables.
656 * On S/390 targets that provide the transactional-execution feature,
657 the program interruption transaction diagnostic block (TDB) is now
658 represented as a number of additional "registers" in GDB.
664 The vCont packet supports a new 'r' action, that tells the remote
665 stub to step through an address range itself, without GDB
666 involvemement at each single-step.
668 qXfer:libraries-svr4:read's annex
669 The previously unused annex of the qXfer:libraries-svr4:read packet
670 is now used to support passing an argument list. The remote stub
671 reports support for this argument list to GDB's qSupported query.
672 The defined arguments are "start" and "prev", used to reduce work
673 necessary for library list updating, resulting in significant
676 * New features in the GDB remote stub, GDBserver
678 ** GDBserver now supports target-assisted range stepping. Currently
679 enabled on x86/x86_64 GNU/Linux targets.
681 ** GDBserver now adds element 'tvar' in the XML in the reply to
682 'qXfer:traceframe-info:read'. It has the id of the collected
683 trace state variables.
685 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
688 * New 'z' formatter for printing and examining memory, this displays the
689 value as hexadecimal zero padded on the left to the size of the type.
691 * GDB can now use Windows x64 unwinding data.
693 * The "set remotebaud" command has been replaced by "set serial baud".
694 Similarly, "show remotebaud" has been replaced by "show serial baud".
695 The "set remotebaud" and "show remotebaud" commands are still available
696 to provide backward compatibility with older versions of GDB.
698 *** Changes in GDB 7.6
700 * Target record has been renamed to record-full.
701 Record/replay is now enabled with the "record full" command.
702 This also affects settings that are associated with full record/replay
703 that have been moved from "set/show record" to "set/show record full":
705 set|show record full insn-number-max
706 set|show record full stop-at-limit
707 set|show record full memory-query
709 * A new record target "record-btrace" has been added. The new target
710 uses hardware support to record the control-flow of a process. It
711 does not support replaying the execution, but it implements the
712 below new commands for investigating the recorded execution log.
713 This new recording method can be enabled using:
717 The "record-btrace" target is only available on Intel Atom processors
718 and requires a Linux kernel 2.6.32 or later.
720 * Two new commands have been added for record/replay to give information
721 about the recorded execution without having to replay the execution.
722 The commands are only supported by "record btrace".
724 record instruction-history prints the execution history at
725 instruction granularity
727 record function-call-history prints the execution history at
730 * New native configurations
732 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
733 FreeBSD/powerpc powerpc*-*-freebsd
734 x86_64/Cygwin x86_64-*-cygwin*
735 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
739 ARM AArch64 aarch64*-*-elf
740 ARM AArch64 GNU/Linux aarch64*-*-linux
741 Lynx 178 PowerPC powerpc-*-lynx*178
742 x86_64/Cygwin x86_64-*-cygwin*
743 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
745 * If the configured location of system.gdbinit file (as given by the
746 --with-system-gdbinit option at configure time) is in the
747 data-directory (as specified by --with-gdb-datadir at configure
748 time) or in one of its subdirectories, then GDB will look for the
749 system-wide init file in the directory specified by the
750 --data-directory command-line option.
752 * New command line options:
754 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
755 other initialization files, unlike -nx which disables all of them.
757 * Removed command line options
759 -epoch This was used by the gdb mode in Epoch, an ancient fork of
762 * The 'ptype' and 'whatis' commands now accept an argument to control
765 * 'info proc' now works on some core files.
769 ** Vectors can be created with gdb.Type.vector.
771 ** Python's atexit.register now works in GDB.
773 ** Types can be pretty-printed via a Python API.
775 ** Python 3 is now supported (in addition to Python 2.4 or later)
777 ** New class gdb.Architecture exposes GDB's internal representation
778 of architecture in the Python API.
780 ** New method Frame.architecture returns the gdb.Architecture object
781 corresponding to the frame's architecture.
783 * New Python-based convenience functions:
785 ** $_memeq(buf1, buf2, length)
786 ** $_streq(str1, str2)
788 ** $_regex(str, regex)
790 * The 'cd' command now defaults to using '~' (the home directory) if not
793 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
794 default for GCC since November 2000.
796 * The command 'forward-search' can now be abbreviated as 'fo'.
798 * The command 'info tracepoints' can now display 'installed on target'
799 or 'not installed on target' for each non-pending location of tracepoint.
801 * New configure options
803 --enable-libmcheck/--disable-libmcheck
804 By default, development versions are built with -lmcheck on hosts
805 that support it, in order to help track memory corruption issues.
806 Release versions, on the other hand, are built without -lmcheck
807 by default. The --enable-libmcheck/--disable-libmcheck configure
808 options allow the user to override that default.
809 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
810 This configure option allows the user to build GDB with
811 libbabeltrace using which GDB can read Common Trace Format data.
813 * New commands (for set/show, see "New options" below)
816 Catch signals. This is similar to "handle", but allows commands and
817 conditions to be attached.
820 List the BFDs known to GDB.
822 python-interactive [command]
824 Start a Python interactive prompt, or evaluate the optional command
825 and print the result of expressions.
828 "py" is a new alias for "python".
830 enable type-printer [name]...
831 disable type-printer [name]...
832 Enable or disable type printers.
836 ** For the Renesas Super-H architecture, the "regs" command has been removed
837 (has been deprecated in GDB 7.5), and "info all-registers" should be used
842 set print type methods (on|off)
843 show print type methods
844 Control whether method declarations are displayed by "ptype".
845 The default is to show them.
847 set print type typedefs (on|off)
848 show print type typedefs
849 Control whether typedef definitions are displayed by "ptype".
850 The default is to show them.
852 set filename-display basename|relative|absolute
853 show filename-display
854 Control the way in which filenames is displayed.
855 The default is "relative", which preserves previous behavior.
857 set trace-buffer-size
858 show trace-buffer-size
859 Request target to change the size of trace buffer.
861 set remote trace-buffer-size-packet auto|on|off
862 show remote trace-buffer-size-packet
863 Control the use of the remote protocol `QTBuffer:size' packet.
867 Control display of debugging messages related to ARM AArch64.
870 set debug coff-pe-read
871 show debug coff-pe-read
872 Control display of debugging messages related to reading of COFF/PE
877 Control display of debugging messages related to Mach-O symbols
880 set debug notification
881 show debug notification
882 Control display of debugging info for async remote notification.
886 ** Command parameter changes are now notified using new async record
887 "=cmd-param-changed".
888 ** Trace frame changes caused by command "tfind" are now notified using
889 new async record "=traceframe-changed".
890 ** The creation, deletion and modification of trace state variables
891 are now notified using new async records "=tsv-created",
892 "=tsv-deleted" and "=tsv-modified".
893 ** The start and stop of process record are now notified using new
894 async record "=record-started" and "=record-stopped".
895 ** Memory changes are now notified using new async record
897 ** The data-disassemble command response will include a "fullname" field
898 containing the absolute file name when source has been requested.
899 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
900 command, to allow pattern filling of memory areas.
901 ** New commands "-catch-load"/"-catch-unload" added for intercepting
902 library load/unload events.
903 ** The response to breakpoint commands and breakpoint async records
904 includes an "installed" field containing a boolean state about each
905 non-pending tracepoint location is whether installed on target or not.
906 ** Output of the "-trace-status" command includes a "trace-file" field
907 containing the name of the trace file being examined. This field is
908 optional, and only present when examining a trace file.
909 ** The "fullname" field is now always present along with the "file" field,
910 even if the file cannot be found by GDB.
912 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
913 You must have the LZMA library available when configuring GDB for this
914 feature to be enabled. For more information, see:
915 http://fedoraproject.org/wiki/Features/MiniDebugInfo
920 Set the size of trace buffer. The remote stub reports support for this
921 packet to gdb's qSupported query.
924 Enable Branch Trace Store (BTS)-based branch tracing for the current
925 thread. The remote stub reports support for this packet to gdb's
929 Disable branch tracing for the current thread. The remote stub reports
930 support for this packet to gdb's qSupported query.
933 Read the traced branches for the current thread. The remote stub
934 reports support for this packet to gdb's qSupported query.
936 *** Changes in GDB 7.5
938 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
939 for more x32 ABI info.
941 * GDB now supports access to MIPS DSP registers on Linux targets.
943 * GDB now supports debugging microMIPS binaries.
945 * The "info os" command on GNU/Linux can now display information on
946 several new classes of objects managed by the operating system:
947 "info os procgroups" lists process groups
948 "info os files" lists file descriptors
949 "info os sockets" lists internet-domain sockets
950 "info os shm" lists shared-memory regions
951 "info os semaphores" lists semaphores
952 "info os msg" lists message queues
953 "info os modules" lists loaded kernel modules
955 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
956 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
957 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
958 options and inspect the probe arguments using the new $_probe_arg family
959 of convenience variables. You can obtain more information about SystemTap
960 in <http://sourceware.org/systemtap/>.
962 * GDB now supports reversible debugging on ARM, it allows you to
963 debug basic ARM and THUMB instructions, and provides
964 record/replay support.
966 * The option "symbol-reloading" has been deleted as it is no longer used.
970 ** GDB commands implemented in Python can now be put in command class
973 ** The "maint set python print-stack on|off" is now deleted.
975 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
976 apply "flag enum"-style pretty-printing to any enum.
978 ** gdb.lookup_symbol can now work when there is no current frame.
980 ** gdb.Symbol now has a 'line' attribute, holding the line number in
981 the source at which the symbol was defined.
983 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
984 method 'value'. The former indicates whether the symbol needs a
985 frame in order to compute its value, and the latter computes the
988 ** A new method 'referenced_value' on gdb.Value objects which can
989 dereference pointer as well as C++ reference values.
991 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
992 which return the global and static blocks (as gdb.Block objects),
993 of the underlying symbol table, respectively.
995 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
996 object associated with a PC value.
998 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
999 of the address range occupied by code for the current source line.
1001 * Go language support.
1002 GDB now supports debugging programs written in the Go programming
1005 * GDBserver now supports stdio connections.
1006 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1008 * The binary "gdbtui" can no longer be built or installed.
1009 Use "gdb -tui" instead.
1011 * GDB will now print "flag" enums specially. A flag enum is one where
1012 all the enumerator values have no bits in common when pairwise
1013 "and"ed. When printing a value whose type is a flag enum, GDB will
1014 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1015 (gdb) print (enum E) 3
1018 * The filename part of a linespec will now match trailing components
1019 of a source file name. For example, "break gcc/expr.c:1000" will
1020 now set a breakpoint in build/gcc/expr.c, but not
1021 build/libcpp/expr.c.
1023 * The "info proc" and "generate-core-file" commands will now also
1024 work on remote targets connected to GDBserver on Linux.
1026 * The command "info catch" has been removed. It has been disabled
1027 since December 2007.
1029 * The "catch exception" and "catch assert" commands now accept
1030 a condition at the end of the command, much like the "break"
1031 command does. For instance:
1033 (gdb) catch exception Constraint_Error if Barrier = True
1035 Previously, it was possible to add a condition to such catchpoints,
1036 but it had to be done as a second step, after the catchpoint had been
1037 created, using the "condition" command.
1039 * The "info static-tracepoint-marker" command will now also work on
1040 native Linux targets with in-process agent.
1042 * GDB can now set breakpoints on inlined functions.
1044 * The .gdb_index section has been updated to include symbols for
1045 inlined functions. GDB will ignore older .gdb_index sections by
1046 default, which could cause symbol files to be loaded more slowly
1047 until their .gdb_index sections can be recreated. The new command
1048 "set use-deprecated-index-sections on" will cause GDB to use any older
1049 .gdb_index sections it finds. This will restore performance, but the
1050 ability to set breakpoints on inlined functions will be lost in symbol
1051 files with older .gdb_index sections.
1053 The .gdb_index section has also been updated to record more information
1054 about each symbol. This speeds up the "info variables", "info functions"
1055 and "info types" commands when used with programs having the .gdb_index
1056 section, as well as speeding up debugging with shared libraries using
1057 the .gdb_index section.
1059 * Ada support for GDB/MI Variable Objects has been added.
1061 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1066 ** New command -info-os is the MI equivalent of "info os".
1068 ** Output logs ("set logging" and related) now include MI output.
1072 ** "set use-deprecated-index-sections on|off"
1073 "show use-deprecated-index-sections on|off"
1074 Controls the use of deprecated .gdb_index sections.
1076 ** "catch load" and "catch unload" can be used to stop when a shared
1077 library is loaded or unloaded, respectively.
1079 ** "enable count" can be used to auto-disable a breakpoint after
1082 ** "info vtbl" can be used to show the virtual method tables for
1083 C++ and Java objects.
1085 ** "explore" and its sub commands "explore value" and "explore type"
1086 can be used to recursively explore values and types of
1087 expressions. These commands are available only if GDB is
1088 configured with '--with-python'.
1090 ** "info auto-load" shows status of all kinds of auto-loaded files,
1091 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1092 sequences of commands files, "info auto-load python-scripts"
1093 shows status of auto-loading Python script files,
1094 "info auto-load local-gdbinit" shows status of loading init file
1095 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1096 status of inferior specific thread debugging shared library loading.
1098 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1099 and "show auto-load-scripts" commands have been deprecated, use their
1100 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1101 and "show auto-load python-scripts" counterparts instead.
1103 ** "dprintf location,format,args..." creates a dynamic printf, which
1104 is basically a breakpoint that does a printf and immediately
1105 resumes your program's execution, so it is like a printf that you
1106 can insert dynamically at runtime instead of at compiletime.
1108 ** "set print symbol"
1110 Controls whether GDB attempts to display the symbol, if any,
1111 corresponding to addresses it prints. This defaults to "on", but
1112 you can set it to "off" to restore GDB's previous behavior.
1114 * Deprecated commands
1116 ** For the Renesas Super-H architecture, the "regs" command has been
1117 deprecated, and "info all-registers" should be used instead.
1121 Renesas RL78 rl78-*-elf
1122 HP OpenVMS ia64 ia64-hp-openvms*
1124 * GDBserver supports evaluation of breakpoint conditions. When
1125 support is advertised by GDBserver, GDB may be told to send the
1126 breakpoint conditions in bytecode form to GDBserver. GDBserver
1127 will only report the breakpoint trigger to GDB when its condition
1132 set mips compression
1133 show mips compression
1134 Select the compressed ISA encoding used in functions that have no symbol
1135 information available. The encoding can be set to either of:
1138 and is updated automatically from ELF file flags if available.
1140 set breakpoint condition-evaluation
1141 show breakpoint condition-evaluation
1142 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1143 GDBserver ("target"). Default option "auto" chooses the most efficient
1145 This option can improve debugger efficiency depending on the speed of the
1149 Disable auto-loading globally.
1152 Show auto-loading setting of all kinds of auto-loaded files.
1154 set auto-load gdb-scripts on|off
1155 show auto-load gdb-scripts
1156 Control auto-loading of GDB canned sequences of commands files.
1158 set auto-load python-scripts on|off
1159 show auto-load python-scripts
1160 Control auto-loading of Python script files.
1162 set auto-load local-gdbinit on|off
1163 show auto-load local-gdbinit
1164 Control loading of init file (.gdbinit) from current directory.
1166 set auto-load libthread-db on|off
1167 show auto-load libthread-db
1168 Control auto-loading of inferior specific thread debugging shared library.
1170 set auto-load scripts-directory <dir1>[:<dir2>...]
1171 show auto-load scripts-directory
1172 Set a list of directories from which to load auto-loaded scripts.
1173 Automatically loaded Python scripts and GDB scripts are located in one
1174 of the directories listed by this option.
1175 The delimiter (':' above) may differ according to the host platform.
1177 set auto-load safe-path <dir1>[:<dir2>...]
1178 show auto-load safe-path
1179 Set a list of directories from which it is safe to auto-load files.
1180 The delimiter (':' above) may differ according to the host platform.
1182 set debug auto-load on|off
1183 show debug auto-load
1184 Control display of debugging info for auto-loading the files above.
1186 set dprintf-style gdb|call|agent
1188 Control the way in which a dynamic printf is performed; "gdb"
1189 requests a GDB printf command, while "call" causes dprintf to call a
1190 function in the inferior. "agent" requests that the target agent
1191 (such as GDBserver) do the printing.
1193 set dprintf-function <expr>
1194 show dprintf-function
1195 set dprintf-channel <expr>
1196 show dprintf-channel
1197 Set the function and optional first argument to the call when using
1198 the "call" style of dynamic printf.
1200 set disconnected-dprintf on|off
1201 show disconnected-dprintf
1202 Control whether agent-style dynamic printfs continue to be in effect
1203 after GDB disconnects.
1205 * New configure options
1207 --with-auto-load-dir
1208 Configure default value for the 'set auto-load scripts-directory'
1209 setting above. It defaults to '$debugdir:$datadir/auto-load',
1210 $debugdir representing global debugging info directories (available
1211 via 'show debug-file-directory') and $datadir representing GDB's data
1212 directory (available via 'show data-directory').
1214 --with-auto-load-safe-path
1215 Configure default value for the 'set auto-load safe-path' setting
1216 above. It defaults to the --with-auto-load-dir setting.
1218 --without-auto-load-safe-path
1219 Set 'set auto-load safe-path' to '/', effectively disabling this
1222 * New remote packets
1224 z0/z1 conditional breakpoints extension
1226 The z0/z1 breakpoint insertion packets have been extended to carry
1227 a list of conditional expressions over to the remote stub depending on the
1228 condition evaluation mode. The use of this extension can be controlled
1229 via the "set remote conditional-breakpoints-packet" command.
1233 Specify the signals which the remote stub may pass to the debugged
1234 program without GDB involvement.
1236 * New command line options
1238 --init-command=FILE, -ix Like --command, -x but execute it
1239 before loading inferior.
1240 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1241 execute it before loading inferior.
1243 *** Changes in GDB 7.4
1245 * GDB now handles ambiguous linespecs more consistently; the existing
1246 FILE:LINE support has been expanded to other types of linespecs. A
1247 breakpoint will now be set on all matching locations in all
1248 inferiors, and locations will be added or removed according to
1251 * GDB now allows you to skip uninteresting functions and files when
1252 stepping with the "skip function" and "skip file" commands.
1254 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1255 and "show remote hardware-watchpoint-length-limit". These allows to
1256 set or show the maximum length limit (in bytes) of a remote
1257 target hardware watchpoint.
1259 This allows e.g. to use "unlimited" hardware watchpoints with the
1260 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1261 watchpoints are slower than real hardware watchpoints but are
1262 significantly faster than gdb software watchpoints.
1266 ** The register_pretty_printer function in module gdb.printing now takes
1267 an optional `replace' argument. If True, the new printer replaces any
1270 ** The "maint set python print-stack on|off" command has been
1271 deprecated and will be deleted in GDB 7.5.
1272 A new command: "set python print-stack none|full|message" has
1273 replaced it. Additionally, the default for "print-stack" is
1274 now "message", which just prints the error message without
1277 ** A prompt substitution hook (prompt_hook) is now available to the
1280 ** A new Python module, gdb.prompt has been added to the GDB Python
1281 modules library. This module provides functionality for
1282 escape sequences in prompts (used by set/show
1283 extended-prompt). These escape sequences are replaced by their
1284 corresponding value.
1286 ** Python commands and convenience-functions located in
1287 'data-directory'/python/gdb/command and
1288 'data-directory'/python/gdb/function are now automatically loaded
1291 ** Blocks now provide four new attributes. global_block and
1292 static_block will return the global and static blocks
1293 respectively. is_static and is_global are boolean attributes
1294 that indicate if the block is one of those two types.
1296 ** Symbols now provide the "type" attribute, the type of the symbol.
1298 ** The "gdb.breakpoint" function has been deprecated in favor of
1301 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1302 of a function. This class is based on the "finish" command
1303 available in the CLI.
1305 ** Type objects for struct and union types now allow access to
1306 the fields using standard Python dictionary (mapping) methods.
1307 For example, "some_type['myfield']" now works, as does
1308 "some_type.items()".
1310 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1313 ** A new function, "deep_items" has been added to the gdb.types
1314 module in the GDB Python modules library. This function returns
1315 an iterator over the fields of a struct or union type. Unlike
1316 the standard Python "iteritems" method, it will recursively traverse
1317 any anonymous fields.
1321 ** "*stopped" events can report several new "reason"s, such as
1324 ** Breakpoint changes are now notified using new async records, like
1325 "=breakpoint-modified".
1327 ** New command -ada-task-info.
1329 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1330 $sdir specifies the default system locations of shared libraries.
1331 $pdir specifies the directory where the libpthread used by the application
1334 GDB no longer looks in $sdir and $pdir after it has searched the directories
1335 mentioned in libthread-db-search-path. If you want to search those
1336 directories, they must be specified in libthread-db-search-path.
1337 The default value of libthread-db-search-path on GNU/Linux and Solaris
1338 systems is now "$sdir:$pdir".
1340 $pdir is not supported by gdbserver, it is currently ignored.
1341 $sdir is supported by gdbserver.
1343 * New configure option --with-iconv-bin.
1344 When using the internationalization support like the one in the GNU C
1345 library, GDB will invoke the "iconv" program to get a list of supported
1346 character sets. If this program lives in a non-standard location, one can
1347 use this option to specify where to find it.
1349 * When natively debugging programs on PowerPC BookE processors running
1350 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1351 watchpoints, which specify a mask in addition to an address to watch.
1352 The mask specifies that some bits of an address (the bits which are
1353 reset in the mask) should be ignored when matching the address accessed
1354 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1355 section in the user manual for more details.
1357 * The new option --once causes GDBserver to stop listening for connections once
1358 the first connection is made. The listening port used by GDBserver will
1359 become available after that.
1361 * New commands "info macros" and "alias" have been added.
1363 * New function parameters suffix @entry specifies value of function parameter
1364 at the time the function got called. Entry values are available only since
1370 "!" is now an alias of the "shell" command.
1371 Note that no space is needed between "!" and SHELL COMMAND.
1375 watch EXPRESSION mask MASK_VALUE
1376 The watch command now supports the mask argument which allows creation
1377 of masked watchpoints, if the current architecture supports this feature.
1379 info auto-load-scripts [REGEXP]
1380 This command was formerly named "maintenance print section-scripts".
1381 It is now generally useful and is no longer a maintenance-only command.
1383 info macro [-all] [--] MACRO
1384 The info macro command has new options `-all' and `--'. The first for
1385 printing all definitions of a macro. The second for explicitly specifying
1386 the end of arguments and the beginning of the macro name in case the macro
1387 name starts with a hyphen.
1389 collect[/s] EXPRESSIONS
1390 The tracepoint collect command now takes an optional modifier "/s"
1391 that directs it to dereference pointer-to-character types and
1392 collect the bytes of memory up to a zero byte. The behavior is
1393 similar to what you see when you use the regular print command on a
1394 string. An optional integer following the "/s" sets a bound on the
1395 number of bytes that will be collected.
1398 The trace start command now interprets any supplied arguments as a
1399 note to be recorded with the trace run, with an effect similar to
1400 setting the variable trace-notes.
1403 The trace stop command now interprets any arguments as a note to be
1404 mentioned along with the tstatus report that the trace was stopped
1405 with a command. The effect is similar to setting the variable
1408 * Tracepoints can now be enabled and disabled at any time after a trace
1409 experiment has been started using the standard "enable" and "disable"
1410 commands. It is now possible to start a trace experiment with no enabled
1411 tracepoints; GDB will display a warning, but will allow the experiment to
1412 begin, assuming that tracepoints will be enabled as needed while the trace
1415 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1416 locations with 4-byte instructions, when they were previously
1417 limited to locations with instructions of 5 bytes or longer.
1421 set debug dwarf2-read
1422 show debug dwarf2-read
1423 Turns on or off display of debugging messages related to reading
1424 DWARF debug info. The default is off.
1426 set debug symtab-create
1427 show debug symtab-create
1428 Turns on or off display of debugging messages related to symbol table
1429 creation. The default is off.
1432 show extended-prompt
1433 Set the GDB prompt, and allow escape sequences to be inserted to
1434 display miscellaneous information (see 'help set extended-prompt'
1435 for the list of sequences). This prompt (and any information
1436 accessed through the escape sequences) is updated every time the
1437 prompt is displayed.
1439 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1440 show print entry-values
1441 Set printing of frame argument values at function entry. In some cases
1442 GDB can determine the value of function argument which was passed by the
1443 function caller, even if the value was modified inside the called function.
1445 set debug entry-values
1446 show debug entry-values
1447 Control display of debugging info for determining frame argument values at
1448 function entry and virtual tail call frames.
1450 set basenames-may-differ
1451 show basenames-may-differ
1452 Set whether a source file may have multiple base names.
1453 (A "base name" is the name of a file with the directory part removed.
1454 Example: The base name of "/home/user/hello.c" is "hello.c".)
1455 If set, GDB will canonicalize file names (e.g., expand symlinks)
1456 before comparing them. Canonicalization is an expensive operation,
1457 but it allows the same file be known by more than one base name.
1458 If not set (the default), all source files are assumed to have just
1459 one base name, and gdb will do file name comparisons more efficiently.
1465 Set a user name and notes for the current and any future trace runs.
1466 This is useful for long-running and/or disconnected traces, to
1467 inform others (or yourself) as to who is running the trace, supply
1468 contact information, or otherwise explain what is going on.
1470 set trace-stop-notes
1471 show trace-stop-notes
1472 Set a note attached to the trace run, that is displayed when the
1473 trace has been stopped by a tstop command. This is useful for
1474 instance as an explanation, if you are stopping a trace run that was
1475 started by someone else.
1477 * New remote packets
1481 Dynamically enable a tracepoint in a started trace experiment.
1485 Dynamically disable a tracepoint in a started trace experiment.
1489 Set the user and notes of the trace run.
1493 Query the current status of a tracepoint.
1497 Query the minimum length of instruction at which a fast tracepoint may
1500 * Dcache size (number of lines) and line-size are now runtime-configurable
1501 via "set dcache line" and "set dcache line-size" commands.
1505 Texas Instruments TMS320C6x tic6x-*-*
1509 Renesas RL78 rl78-*-elf
1511 *** Changes in GDB 7.3.1
1513 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1515 *** Changes in GDB 7.3
1517 * GDB has a new command: "thread find [REGEXP]".
1518 It finds the thread id whose name, target id, or thread extra info
1519 matches the given regular expression.
1521 * The "catch syscall" command now works on mips*-linux* targets.
1523 * The -data-disassemble MI command now supports modes 2 and 3 for
1524 dumping the instruction opcodes.
1526 * New command line options
1528 -data-directory DIR Specify DIR as the "data-directory".
1529 This is mostly for testing purposes.
1531 * The "maint set python auto-load on|off" command has been renamed to
1532 "set auto-load-scripts on|off".
1534 * GDB has a new command: "set directories".
1535 It is like the "dir" command except that it replaces the
1536 source path list instead of augmenting it.
1538 * GDB now understands thread names.
1540 On GNU/Linux, "info threads" will display the thread name as set by
1541 prctl or pthread_setname_np.
1543 There is also a new command, "thread name", which can be used to
1544 assign a name internally for GDB to display.
1547 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1548 has been integrated into GDB.
1552 ** The function gdb.Write now accepts an optional keyword 'stream'.
1553 This keyword, when provided, will direct the output to either
1554 stdout, stderr, or GDB's logging output.
1556 ** Parameters can now be be sub-classed in Python, and in particular
1557 you may implement the get_set_doc and get_show_doc functions.
1558 This improves how Parameter set/show documentation is processed
1559 and allows for more dynamic content.
1561 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1562 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1563 have an is_valid method.
1565 ** Breakpoints can now be sub-classed in Python, and in particular
1566 you may implement a 'stop' function that is executed each time
1567 the inferior reaches that breakpoint.
1569 ** New function gdb.lookup_global_symbol looks up a global symbol.
1571 ** GDB values in Python are now callable if the value represents a
1572 function. For example, if 'some_value' represents a function that
1573 takes two integer parameters and returns a value, you can call
1574 that function like so:
1576 result = some_value (10,20)
1578 ** Module gdb.types has been added.
1579 It contains a collection of utilities for working with gdb.Types objects:
1580 get_basic_type, has_field, make_enum_dict.
1582 ** Module gdb.printing has been added.
1583 It contains utilities for writing and registering pretty-printers.
1584 New classes: PrettyPrinter, SubPrettyPrinter,
1585 RegexpCollectionPrettyPrinter.
1586 New function: register_pretty_printer.
1588 ** New commands "info pretty-printers", "enable pretty-printer" and
1589 "disable pretty-printer" have been added.
1591 ** gdb.parameter("directories") is now available.
1593 ** New function gdb.newest_frame returns the newest frame in the
1596 ** The gdb.InferiorThread class has a new "name" attribute. This
1597 holds the thread's name.
1599 ** Python Support for Inferior events.
1600 Python scripts can add observers to be notified of events
1601 occurring in the process being debugged.
1602 The following events are currently supported:
1603 - gdb.events.cont Continue event.
1604 - gdb.events.exited Inferior exited event.
1605 - gdb.events.stop Signal received, and Breakpoint hit events.
1609 ** GDB now puts template parameters in scope when debugging in an
1610 instantiation. For example, if you have:
1612 template<int X> int func (void) { return X; }
1614 then if you step into func<5>, "print X" will show "5". This
1615 feature requires proper debuginfo support from the compiler; it
1616 was added to GCC 4.5.
1618 ** The motion commands "next", "finish", "until", and "advance" now
1619 work better when exceptions are thrown. In particular, GDB will
1620 no longer lose control of the inferior; instead, the GDB will
1621 stop the inferior at the point at which the exception is caught.
1622 This functionality requires a change in the exception handling
1623 code that was introduced in GCC 4.5.
1625 * GDB now follows GCC's rules on accessing volatile objects when
1626 reading or writing target state during expression evaluation.
1627 One notable difference to prior behavior is that "print x = 0"
1628 no longer generates a read of x; the value of the assignment is
1629 now always taken directly from the value being assigned.
1631 * GDB now has some support for using labels in the program's source in
1632 linespecs. For instance, you can use "advance label" to continue
1633 execution to a label.
1635 * GDB now has support for reading and writing a new .gdb_index
1636 section. This section holds a fast index of DWARF debugging
1637 information and can be used to greatly speed up GDB startup and
1638 operation. See the documentation for `save gdb-index' for details.
1640 * The "watch" command now accepts an optional "-location" argument.
1641 When used, this causes GDB to watch the memory referred to by the
1642 expression. Such a watchpoint is never deleted due to it going out
1645 * GDB now supports thread debugging of core dumps on GNU/Linux.
1647 GDB now activates thread debugging using the libthread_db library
1648 when debugging GNU/Linux core dumps, similarly to when debugging
1649 live processes. As a result, when debugging a core dump file, GDB
1650 is now able to display pthread_t ids of threads. For example, "info
1651 threads" shows the same output as when debugging the process when it
1652 was live. In earlier releases, you'd see something like this:
1655 * 1 LWP 6780 main () at main.c:10
1657 While now you see this:
1660 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1662 It is also now possible to inspect TLS variables when debugging core
1665 When debugging a core dump generated on a machine other than the one
1666 used to run GDB, you may need to point GDB at the correct
1667 libthread_db library with the "set libthread-db-search-path"
1668 command. See the user manual for more details on this command.
1670 * When natively debugging programs on PowerPC BookE processors running
1671 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1672 which stop execution of the inferior whenever it executes an instruction
1673 at any address within the specified range. See the "PowerPC Embedded"
1674 section in the user manual for more details.
1676 * New features in the GDB remote stub, GDBserver
1678 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1679 and i686 LynxOS (version 5.x).
1681 ** GDBserver is now supported on Blackfin Linux.
1683 * New native configurations
1685 ia64 HP-UX ia64-*-hpux*
1689 Analog Devices, Inc. Blackfin Processor bfin-*
1691 * Ada task switching is now supported on sparc-elf targets when
1692 debugging a program using the Ravenscar Profile. For more information,
1693 see the "Tasking Support when using the Ravenscar Profile" section
1694 in the GDB user manual.
1696 * Guile support was removed.
1698 * New features in the GNU simulator
1700 ** The --map-info flag lists all known core mappings.
1702 ** CFI flashes may be simulated via the "cfi" device.
1704 *** Changes in GDB 7.2
1706 * Shared library support for remote targets by default
1708 When GDB is configured for a generic, non-OS specific target, like
1709 for example, --target=arm-eabi or one of the many *-*-elf targets,
1710 GDB now queries remote stubs for loaded shared libraries using the
1711 `qXfer:libraries:read' packet. Previously, shared library support
1712 was always disabled for such configurations.
1716 ** Argument Dependent Lookup (ADL)
1718 In C++ ADL lookup directs function search to the namespaces of its
1719 arguments even if the namespace has not been imported.
1729 Here the compiler will search for `foo' in the namespace of 'b'
1730 and find A::foo. GDB now supports this. This construct is commonly
1731 used in the Standard Template Library for operators.
1733 ** Improved User Defined Operator Support
1735 In addition to member operators, GDB now supports lookup of operators
1736 defined in a namespace and imported with a `using' directive, operators
1737 defined in the global scope, operators imported implicitly from an
1738 anonymous namespace, and the ADL operators mentioned in the previous
1740 GDB now also supports proper overload resolution for all the previously
1741 mentioned flavors of operators.
1743 ** static const class members
1745 Printing of static const class members that are initialized in the
1746 class definition has been fixed.
1748 * Windows Thread Information Block access.
1750 On Windows targets, GDB now supports displaying the Windows Thread
1751 Information Block (TIB) structure. This structure is visible either
1752 by using the new command `info w32 thread-information-block' or, by
1753 dereferencing the new convenience variable named `$_tlb', a
1754 thread-specific pointer to the TIB. This feature is also supported
1755 when remote debugging using GDBserver.
1757 * Static tracepoints
1759 Static tracepoints are calls in the user program into a tracing
1760 library. One such library is a port of the LTTng kernel tracer to
1761 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1762 When debugging with GDBserver, GDB now supports combining the GDB
1763 tracepoint machinery with such libraries. For example: the user can
1764 use GDB to probe a static tracepoint marker (a call from the user
1765 program into the tracing library) with the new "strace" command (see
1766 "New commands" below). This creates a "static tracepoint" in the
1767 breakpoint list, that can be manipulated with the same feature set
1768 as fast and regular tracepoints. E.g., collect registers, local and
1769 global variables, collect trace state variables, and define
1770 tracepoint conditions. In addition, the user can collect extra
1771 static tracepoint marker specific data, by collecting the new
1772 $_sdata internal variable. When analyzing the trace buffer, you can
1773 inspect $_sdata like any other variable available to GDB. For more
1774 information, see the "Tracepoints" chapter in GDB user manual. New
1775 remote packets have been defined to support static tracepoints, see
1776 the "New remote packets" section below.
1778 * Better reconstruction of tracepoints after disconnected tracing
1780 GDB will attempt to download the original source form of tracepoint
1781 definitions when starting a trace run, and then will upload these
1782 upon reconnection to the target, resulting in a more accurate
1783 reconstruction of the tracepoints that are in use on the target.
1787 You can now exercise direct control over the ways that GDB can
1788 affect your program. For instance, you can disallow the setting of
1789 breakpoints, so that the program can run continuously (assuming
1790 non-stop mode). In addition, the "observer" variable is available
1791 to switch all of the different controls; in observer mode, GDB
1792 cannot affect the target's behavior at all, which is useful for
1793 tasks like diagnosing live systems in the field.
1795 * The new convenience variable $_thread holds the number of the
1798 * New remote packets
1802 Return the address of the Windows Thread Information Block of a given thread.
1806 In response to several of the tracepoint packets, the target may now
1807 also respond with a number of intermediate `qRelocInsn' request
1808 packets before the final result packet, to have GDB handle
1809 relocating an instruction to execute at a different address. This
1810 is particularly useful for stubs that support fast tracepoints. GDB
1811 reports support for this feature in the qSupported packet.
1815 List static tracepoint markers in the target program.
1819 List static tracepoint markers at a given address in the target
1822 qXfer:statictrace:read
1824 Read the static trace data collected (by a `collect $_sdata'
1825 tracepoint action). The remote stub reports support for this packet
1826 to gdb's qSupported query.
1830 Send the current settings of GDB's permission flags.
1834 Send part of the source (textual) form of a tracepoint definition,
1835 which includes location, conditional, and action list.
1837 * The source command now accepts a -s option to force searching for the
1838 script in the source search path even if the script name specifies
1841 * New features in the GDB remote stub, GDBserver
1843 - GDBserver now support tracepoints (including fast tracepoints, and
1844 static tracepoints). The feature is currently supported by the
1845 i386-linux and amd64-linux builds. See the "Tracepoints support
1846 in gdbserver" section in the manual for more information.
1848 GDBserver JIT compiles the tracepoint's conditional agent
1849 expression bytecode into native code whenever possible for low
1850 overhead dynamic tracepoints conditionals. For such tracepoints,
1851 an expression that examines program state is evaluated when the
1852 tracepoint is reached, in order to determine whether to capture
1853 trace data. If the condition is simple and false, processing the
1854 tracepoint finishes very quickly and no data is gathered.
1856 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1857 for static tracepoints support.
1859 - GDBserver now supports x86_64 Windows 64-bit debugging.
1861 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1862 it understands register description.
1864 * The --batch flag now disables pagination and queries.
1866 * X86 general purpose registers
1868 GDB now supports reading/writing byte, word and double-word x86
1869 general purpose registers directly. This means you can use, say,
1870 $ah or $ax to refer, respectively, to the byte register AH and
1871 16-bit word register AX that are actually portions of the 32-bit
1872 register EAX or 64-bit register RAX.
1874 * The `commands' command now accepts a range of breakpoints to modify.
1875 A plain `commands' following a command that creates multiple
1876 breakpoints affects all the breakpoints set by that command. This
1877 applies to breakpoints set by `rbreak', and also applies when a
1878 single `break' command creates multiple breakpoints (e.g.,
1879 breakpoints on overloaded c++ functions).
1881 * The `rbreak' command now accepts a filename specification as part of
1882 its argument, limiting the functions selected by the regex to those
1883 in the specified file.
1885 * Support for remote debugging Windows and SymbianOS shared libraries
1886 from Unix hosts has been improved. Non Windows GDB builds now can
1887 understand target reported file names that follow MS-DOS based file
1888 system semantics, such as file names that include drive letters and
1889 use the backslash character as directory separator. This makes it
1890 possible to transparently use the "set sysroot" and "set
1891 solib-search-path" on Unix hosts to point as host copies of the
1892 target's shared libraries. See the new command "set
1893 target-file-system-kind" described below, and the "Commands to
1894 specify files" section in the user manual for more information.
1898 eval template, expressions...
1899 Convert the values of one or more expressions under the control
1900 of the string template to a command line, and call it.
1902 set target-file-system-kind unix|dos-based|auto
1903 show target-file-system-kind
1904 Set or show the assumed file system kind for target reported file
1907 save breakpoints <filename>
1908 Save all current breakpoint definitions to a file suitable for use
1909 in a later debugging session. To read the saved breakpoint
1910 definitions, use the `source' command.
1912 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1915 info static-tracepoint-markers
1916 Display information about static tracepoint markers in the target.
1918 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1919 Define a static tracepoint by probing a marker at the given
1920 function, line, address, or marker ID.
1924 Enable and disable observer mode.
1926 set may-write-registers on|off
1927 set may-write-memory on|off
1928 set may-insert-breakpoints on|off
1929 set may-insert-tracepoints on|off
1930 set may-insert-fast-tracepoints on|off
1931 set may-interrupt on|off
1932 Set individual permissions for GDB effects on the target. Note that
1933 some of these settings can have undesirable or surprising
1934 consequences, particularly when changed in the middle of a session.
1935 For instance, disabling the writing of memory can prevent
1936 breakpoints from being inserted, cause single-stepping to fail, or
1937 even crash your program, if you disable after breakpoints have been
1938 inserted. However, GDB should not crash.
1940 set record memory-query on|off
1941 show record memory-query
1942 Control whether to stop the inferior if memory changes caused
1943 by an instruction cannot be recorded.
1948 The disassemble command now supports "start,+length" form of two arguments.
1952 ** GDB now provides a new directory location, called the python directory,
1953 where Python scripts written for GDB can be installed. The location
1954 of that directory is <data-directory>/python, where <data-directory>
1955 is the GDB data directory. For more details, see section `Scripting
1956 GDB using Python' in the manual.
1958 ** The GDB Python API now has access to breakpoints, symbols, symbol
1959 tables, program spaces, inferiors, threads and frame's code blocks.
1960 Additionally, GDB Parameters can now be created from the API, and
1961 manipulated via set/show in the CLI.
1963 ** New functions gdb.target_charset, gdb.target_wide_charset,
1964 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1966 ** New exception gdb.GdbError.
1968 ** Pretty-printers are now also looked up in the current program space.
1970 ** Pretty-printers can now be individually enabled and disabled.
1972 ** GDB now looks for names of Python scripts to auto-load in a
1973 special section named `.debug_gdb_scripts', in addition to looking
1974 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1976 * Tracepoint actions were unified with breakpoint commands. In particular,
1977 there are no longer differences in "info break" output for breakpoints and
1978 tracepoints and the "commands" command can be used for both tracepoints and
1979 regular breakpoints.
1983 ARM Symbian arm*-*-symbianelf*
1985 * D language support.
1986 GDB now supports debugging programs written in the D programming
1989 * GDB now supports the extended ptrace interface for PowerPC which is
1990 available since Linux kernel version 2.6.34. This automatically enables
1991 any hardware breakpoints and additional hardware watchpoints available in
1992 the processor. The old ptrace interface exposes just one hardware
1993 watchpoint and no hardware breakpoints.
1995 * GDB is now able to use the Data Value Compare (DVC) register available on
1996 embedded PowerPC processors to implement in hardware simple watchpoint
1997 conditions of the form:
1999 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2001 This works in native GDB running on Linux kernels with the extended ptrace
2002 interface mentioned above.
2004 *** Changes in GDB 7.1
2008 ** Namespace Support
2010 GDB now supports importing of namespaces in C++. This enables the
2011 user to inspect variables from imported namespaces. Support for
2012 namepace aliasing has also been added. So, if a namespace is
2013 aliased in the current scope (e.g. namepace C=A; ) the user can
2014 print variables using the alias (e.g. (gdb) print C::x).
2018 All known bugs relating to the printing of virtual base class were
2019 fixed. It is now possible to call overloaded static methods using a
2024 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2025 and reinterpret_cast<> are now handled by the C++ expression parser.
2029 Xilinx MicroBlaze microblaze-*-*
2034 Xilinx MicroBlaze microblaze
2037 * Multi-program debugging.
2039 GDB now has support for multi-program (a.k.a. multi-executable or
2040 multi-exec) debugging. This allows for debugging multiple inferiors
2041 simultaneously each running a different program under the same GDB
2042 session. See "Debugging Multiple Inferiors and Programs" in the
2043 manual for more information. This implied some user visible changes
2044 in the multi-inferior support. For example, "info inferiors" now
2045 lists inferiors that are not running yet or that have exited
2046 already. See also "New commands" and "New options" below.
2048 * New tracing features
2050 GDB's tracepoint facility now includes several new features:
2052 ** Trace state variables
2054 GDB tracepoints now include support for trace state variables, which
2055 are variables managed by the target agent during a tracing
2056 experiment. They are useful for tracepoints that trigger each
2057 other, so for instance one tracepoint can count hits in a variable,
2058 and then a second tracepoint has a condition that is true when the
2059 count reaches a particular value. Trace state variables share the
2060 $-syntax of GDB convenience variables, and can appear in both
2061 tracepoint actions and condition expressions. Use the "tvariable"
2062 command to create, and "info tvariables" to view; see "Trace State
2063 Variables" in the manual for more detail.
2067 GDB now includes an option for defining fast tracepoints, which
2068 targets may implement more efficiently, such as by installing a jump
2069 into the target agent rather than a trap instruction. The resulting
2070 speedup can be by two orders of magnitude or more, although the
2071 tradeoff is that some program locations on some target architectures
2072 might not allow fast tracepoint installation, for instance if the
2073 instruction to be replaced is shorter than the jump. To request a
2074 fast tracepoint, use the "ftrace" command, with syntax identical to
2075 the regular trace command.
2077 ** Disconnected tracing
2079 It is now possible to detach GDB from the target while it is running
2080 a trace experiment, then reconnect later to see how the experiment
2081 is going. In addition, a new variable disconnected-tracing lets you
2082 tell the target agent whether to continue running a trace if the
2083 connection is lost unexpectedly.
2087 GDB now has the ability to save the trace buffer into a file, and
2088 then use that file as a target, similarly to you can do with
2089 corefiles. You can select trace frames, print data that was
2090 collected in them, and use tstatus to display the state of the
2091 tracing run at the moment that it was saved. To create a trace
2092 file, use "tsave <filename>", and to use it, do "target tfile
2095 ** Circular trace buffer
2097 You can ask the target agent to handle the trace buffer as a
2098 circular buffer, discarding the oldest trace frames to make room for
2099 newer ones, by setting circular-trace-buffer to on. This feature may
2100 not be available for all target agents.
2105 The disassemble command, when invoked with two arguments, now requires
2106 the arguments to be comma-separated.
2109 The info variables command now displays variable definitions. Files
2110 which only declare a variable are not shown.
2113 The source command is now capable of sourcing Python scripts.
2114 This feature is dependent on the debugger being build with Python
2117 Related to this enhancement is also the introduction of a new command
2118 "set script-extension" (see below).
2120 * New commands (for set/show, see "New options" below)
2122 record save [<FILENAME>]
2123 Save a file (in core file format) containing the process record
2124 execution log for replay debugging at a later time.
2126 record restore <FILENAME>
2127 Restore the process record execution log that was saved at an
2128 earlier time, for replay debugging.
2130 add-inferior [-copies <N>] [-exec <FILENAME>]
2133 clone-inferior [-copies <N>] [ID]
2134 Make a new inferior ready to execute the same program another
2135 inferior has loaded.
2140 maint info program-spaces
2141 List the program spaces loaded into GDB.
2143 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2144 show remote interrupt-sequence
2145 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2146 as the sequence to the remote target in order to interrupt the execution.
2147 Ctrl-C is a default. Some system prefers BREAK which is high level of
2148 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2149 Magic SysRq g. It is BREAK signal and character 'g'.
2151 set remote interrupt-on-connect [on | off]
2152 show remote interrupt-on-connect
2153 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2154 remote target when gdb connects to it. This is needed when you debug
2157 set remotebreak [on | off]
2159 Deprecated. Use "set/show remote interrupt-sequence" instead.
2161 tvariable $NAME [ = EXP ]
2162 Create or modify a trace state variable.
2165 List trace state variables and their values.
2167 delete tvariable $NAME ...
2168 Delete one or more trace state variables.
2171 Evaluate the given expressions without collecting anything into the
2172 trace buffer. (Valid in tracepoint actions only.)
2174 ftrace FN / FILE:LINE / *ADDR
2175 Define a fast tracepoint at the given function, line, or address.
2177 * New expression syntax
2179 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2180 GDB now parses 0b101010 identically with 42.
2184 set follow-exec-mode new|same
2185 show follow-exec-mode
2186 Control whether GDB reuses the same inferior across an exec call or
2187 creates a new one. This is useful to be able to restart the old
2188 executable after the inferior having done an exec call.
2190 set default-collect EXPR, ...
2191 show default-collect
2192 Define a list of expressions to be collected at each tracepoint.
2193 This is a useful way to ensure essential items are not overlooked,
2194 such as registers or a critical global variable.
2196 set disconnected-tracing
2197 show disconnected-tracing
2198 If set to 1, the target is instructed to continue tracing if it
2199 loses its connection to GDB. If 0, the target is to stop tracing
2202 set circular-trace-buffer
2203 show circular-trace-buffer
2204 If set to on, the target is instructed to use a circular trace buffer
2205 and discard the oldest trace frames instead of stopping the trace due
2206 to a full trace buffer. If set to off, the trace stops when the buffer
2207 fills up. Some targets may not support this.
2209 set script-extension off|soft|strict
2210 show script-extension
2211 If set to "off", the debugger does not perform any script language
2212 recognition, and all sourced files are assumed to be GDB scripts.
2213 If set to "soft" (the default), files are sourced according to
2214 filename extension, falling back to GDB scripts if the first
2216 If set to "strict", files are sourced according to filename extension.
2218 set ada trust-PAD-over-XVS on|off
2219 show ada trust-PAD-over-XVS
2220 If off, activate a workaround against a bug in the debugging information
2221 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2222 the GCC sources for more information about the GNAT encoding and
2223 PAD types in particular). It is always safe to set this option to
2224 off, but this introduces a slight performance penalty. The default
2227 * Python API Improvements
2229 ** GDB provides the new class gdb.LazyString. This is useful in
2230 some pretty-printing cases. The new method gdb.Value.lazy_string
2231 provides a simple way to create objects of this type.
2233 ** The fields returned by gdb.Type.fields now have an
2234 `is_base_class' attribute.
2236 ** The new method gdb.Type.range returns the range of an array type.
2238 ** The new method gdb.parse_and_eval can be used to parse and
2239 evaluate an expression.
2241 * New remote packets
2244 Define a trace state variable.
2247 Get the current value of a trace state variable.
2250 Set desired tracing behavior upon disconnection.
2253 Set the trace buffer to be linear or circular.
2256 Get data about the tracepoints currently in use.
2260 Process record now works correctly with hardware watchpoints.
2262 Multiple bug fixes have been made to the mips-irix port, making it
2263 much more reliable. In particular:
2264 - Debugging threaded applications is now possible again. Previously,
2265 GDB would hang while starting the program, or while waiting for
2266 the program to stop at a breakpoint.
2267 - Attaching to a running process no longer hangs.
2268 - An error occurring while loading a core file has been fixed.
2269 - Changing the value of the PC register now works again. This fixes
2270 problems observed when using the "jump" command, or when calling
2271 a function from GDB, or even when assigning a new value to $pc.
2272 - With the "finish" and "return" commands, the return value for functions
2273 returning a small array is now correctly printed.
2274 - It is now possible to break on shared library code which gets executed
2275 during a shared library init phase (code executed while executing
2276 their .init section). Previously, the breakpoint would have no effect.
2277 - GDB is now able to backtrace through the signal handler for
2278 non-threaded programs.
2280 PIE (Position Independent Executable) programs debugging is now supported.
2281 This includes debugging execution of PIC (Position Independent Code) shared
2282 libraries although for that, it should be possible to run such libraries as an
2285 *** Changes in GDB 7.0
2287 * GDB now has an interface for JIT compilation. Applications that
2288 dynamically generate code can create symbol files in memory and register
2289 them with GDB. For users, the feature should work transparently, and
2290 for JIT developers, the interface is documented in the GDB manual in the
2291 "JIT Compilation Interface" chapter.
2293 * Tracepoints may now be conditional. The syntax is as for
2294 breakpoints; either an "if" clause appended to the "trace" command,
2295 or the "condition" command is available. GDB sends the condition to
2296 the target for evaluation using the same bytecode format as is used
2297 for tracepoint actions.
2299 * The disassemble command now supports: an optional /r modifier, print the
2300 raw instructions in hex as well as in symbolic form, and an optional /m
2301 modifier to print mixed source+assembly.
2303 * Process record and replay
2305 In a architecture environment that supports ``process record and
2306 replay'', ``process record and replay'' target can record a log of
2307 the process execution, and replay it with both forward and reverse
2310 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2311 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2312 set execution-direction {forward|reverse}, for targets that support
2315 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2316 feature is available with a native GDB running on kernel version
2319 * GDB now has support for multi-byte and wide character sets on the
2320 target. Strings whose character type is wchar_t, char16_t, or
2321 char32_t are now correctly printed. GDB supports wide- and unicode-
2322 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2323 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2324 `printf'. This feature requires iconv to work properly; if your
2325 system does not have a working iconv, GDB can use GNU libiconv. See
2326 the installation instructions for more information.
2328 * GDB now supports automatic retrieval of shared library files from
2329 remote targets. To use this feature, specify a system root that begins
2330 with the `remote:' prefix, either via the `set sysroot' command or via
2331 the `--with-sysroot' configure-time option.
2333 * "info sharedlibrary" now takes an optional regex of libraries to show,
2334 and it now reports if a shared library has no debugging information.
2336 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2337 now complete on file names.
2339 * When completing in expressions, gdb will attempt to limit
2340 completions to allowable structure or union fields, where appropriate.
2341 For instance, consider:
2343 # struct example { int f1; double f2; };
2344 # struct example variable;
2347 If the user types TAB at the end of this command line, the available
2348 completions will be "f1" and "f2".
2350 * Inlined functions are now supported. They show up in backtraces, and
2351 the "step", "next", and "finish" commands handle them automatically.
2353 * GDB now supports the token-splicing (##) and stringification (#)
2354 operators when expanding macros. It also supports variable-arity
2357 * GDB now supports inspecting extra signal information, exported by
2358 the new $_siginfo convenience variable. The feature is currently
2359 implemented on linux ARM, i386 and amd64.
2361 * GDB can now display the VFP floating point registers and NEON vector
2362 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2363 can provide these registers (requires Linux 2.6.30 or later). Remote
2364 and simulator targets may also provide them.
2366 * New remote packets
2369 Search memory for a sequence of bytes.
2372 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2373 operation over reliable transport links. Use of this packet is
2374 controlled by the `set remote noack-packet' command.
2377 Kill the process with the specified process ID. Use this in preference
2378 to `k' when multiprocess protocol extensions are supported.
2381 Obtains additional operating system information
2385 Read or write additional signal information.
2387 * Removed remote protocol undocumented extension
2389 An undocumented extension to the remote protocol's `S' stop reply
2390 packet that permited the stub to pass a process id was removed.
2391 Remote servers should use the `T' stop reply packet instead.
2393 * GDB now supports multiple function calling conventions according to the
2394 DWARF-2 DW_AT_calling_convention function attribute.
2396 * The SH target utilizes the aforementioned change to distinguish between gcc
2397 and Renesas calling convention. It also adds the new CLI commands
2398 `set/show sh calling-convention'.
2400 * GDB can now read compressed debug sections, as produced by GNU gold
2401 with the --compress-debug-sections=zlib flag.
2403 * 64-bit core files are now supported on AIX.
2405 * Thread switching is now supported on Tru64.
2407 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2408 which will be allocated using malloc later in program execution.
2410 * The qXfer:libraries:read remote procotol packet now allows passing a
2411 list of section offsets.
2413 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2414 conditions handling signals delivered during attach or thread creation
2415 have also been fixed.
2417 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2418 From the user's standpoint, all unqualified instances of True and False
2419 are treated as the standard definitions, regardless of context.
2421 * GDB now parses C++ symbol and type names more flexibly. For
2424 template<typename T> class C { };
2427 GDB will now correctly handle all of:
2429 ptype C<char const *>
2430 ptype C<char const*>
2431 ptype C<const char *>
2432 ptype C<const char*>
2434 * New features in the GDB remote stub, gdbserver
2436 - The "--wrapper" command-line argument tells gdbserver to use a
2437 wrapper program to launch programs for debugging.
2439 - On PowerPC and S/390 targets, it is now possible to use a single
2440 gdbserver executable to debug both 32-bit and 64-bit programs.
2441 (This requires gdbserver itself to be built as a 64-bit executable.)
2443 - gdbserver uses the new noack protocol mode for TCP connections to
2444 reduce communications latency, if also supported and enabled in GDB.
2446 - Support for the sparc64-linux-gnu target is now included in
2449 - The amd64-linux build of gdbserver now supports debugging both
2450 32-bit and 64-bit programs.
2452 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2453 now support hardware watchpoints, and will use them automatically
2458 GDB now has support for scripting using Python. Whether this is
2459 available is determined at configure time.
2461 New GDB commands can now be written in Python.
2463 * Ada tasking support
2465 Ada tasks can now be inspected in GDB. The following commands have
2469 Print the list of Ada tasks.
2471 Print detailed information about task number N.
2473 Print the task number of the current task.
2475 Switch the context of debugging to task number N.
2477 * Support for user-defined prefixed commands. The "define" command can
2478 add new commands to existing prefixes, e.g. "target".
2480 * Multi-inferior, multi-process debugging.
2482 GDB now has generalized support for multi-inferior debugging. See
2483 "Debugging Multiple Inferiors" in the manual for more information.
2484 Although availability still depends on target support, the command
2485 set is more uniform now. The GNU/Linux specific multi-forks support
2486 has been migrated to this new framework. This implied some user
2487 visible changes; see "New commands" and also "Removed commands"
2490 * Target descriptions can now describe the target OS ABI. See the
2491 "Target Description Format" section in the user manual for more
2494 * Target descriptions can now describe "compatible" architectures
2495 to indicate that the target can execute applications for a different
2496 architecture in addition to those for the main target architecture.
2497 See the "Target Description Format" section in the user manual for
2500 * Multi-architecture debugging.
2502 GDB now includes general supports for debugging applications on
2503 hybrid systems that use more than one single processor architecture
2504 at the same time. Each such hybrid architecture still requires
2505 specific support to be added. The only hybrid architecture supported
2506 in this version of GDB is the Cell Broadband Engine.
2508 * GDB now supports integrated debugging of Cell/B.E. applications that
2509 use both the PPU and SPU architectures. To enable support for hybrid
2510 Cell/B.E. debugging, you need to configure GDB to support both the
2511 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2512 --enable-targets configure option.
2514 * Non-stop mode debugging.
2516 For some targets, GDB now supports an optional mode of operation in
2517 which you can examine stopped threads while other threads continue
2518 to execute freely. This is referred to as non-stop mode, with the
2519 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2520 section in the user manual for more information.
2522 To be able to support remote non-stop debugging, a remote stub needs
2523 to implement the non-stop mode remote protocol extensions, as
2524 described in the "Remote Non-Stop" section of the user manual. The
2525 GDB remote stub, gdbserver, has been adjusted to support these
2526 extensions on linux targets.
2528 * New commands (for set/show, see "New options" below)
2530 catch syscall [NAME(S) | NUMBER(S)]
2531 Catch system calls. Arguments, which should be names of system
2532 calls or their numbers, mean catch only those syscalls. Without
2533 arguments, every syscall will be caught. When the inferior issues
2534 any of the specified syscalls, GDB will stop and announce the system
2535 call, both when it is called and when its call returns. This
2536 feature is currently available with a native GDB running on the
2537 Linux Kernel, under the following architectures: x86, x86_64,
2538 PowerPC and PowerPC64.
2540 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2542 Search memory for a sequence of bytes.
2544 maint set python print-stack
2545 maint show python print-stack
2546 Show a stack trace when an error is encountered in a Python script.
2549 Invoke CODE by passing it to the Python interpreter.
2554 These allow macros to be defined, undefined, and listed
2558 Show operating system information about processes.
2561 List the inferiors currently under GDB's control.
2564 Switch focus to inferior number NUM.
2567 Detach from inferior number NUM.
2570 Kill inferior number NUM.
2574 set spu stop-on-load
2575 show spu stop-on-load
2576 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2578 set spu auto-flush-cache
2579 show spu auto-flush-cache
2580 Control whether to automatically flush the software-managed cache
2581 during Cell/B.E. debugging.
2583 set sh calling-convention
2584 show sh calling-convention
2585 Control the calling convention used when calling SH target functions.
2588 show debug timestamp
2589 Control display of timestamps with GDB debugging output.
2591 set disassemble-next-line
2592 show disassemble-next-line
2593 Control display of disassembled source lines or instructions when
2596 set remote noack-packet
2597 show remote noack-packet
2598 Set/show the use of remote protocol QStartNoAckMode packet. See above
2599 under "New remote packets."
2601 set remote query-attached-packet
2602 show remote query-attached-packet
2603 Control use of remote protocol `qAttached' (query-attached) packet.
2605 set remote read-siginfo-object
2606 show remote read-siginfo-object
2607 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2610 set remote write-siginfo-object
2611 show remote write-siginfo-object
2612 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2615 set remote reverse-continue
2616 show remote reverse-continue
2617 Control use of remote protocol 'bc' (reverse-continue) packet.
2619 set remote reverse-step
2620 show remote reverse-step
2621 Control use of remote protocol 'bs' (reverse-step) packet.
2623 set displaced-stepping
2624 show displaced-stepping
2625 Control displaced stepping mode. Displaced stepping is a way to
2626 single-step over breakpoints without removing them from the debuggee.
2627 Also known as "out-of-line single-stepping".
2630 show debug displaced
2631 Control display of debugging info for displaced stepping.
2633 maint set internal-error
2634 maint show internal-error
2635 Control what GDB does when an internal error is detected.
2637 maint set internal-warning
2638 maint show internal-warning
2639 Control what GDB does when an internal warning is detected.
2644 Use a wrapper program to launch programs for debugging.
2646 set multiple-symbols (all|ask|cancel)
2647 show multiple-symbols
2648 The value of this variable can be changed to adjust the debugger behavior
2649 when an expression or a breakpoint location contains an ambiguous symbol
2650 name (an overloaded function name, for instance).
2652 set breakpoint always-inserted
2653 show breakpoint always-inserted
2654 Keep breakpoints always inserted in the target, as opposed to inserting
2655 them when resuming the target, and removing them when the target stops.
2656 This option can improve debugger performance on slow remote targets.
2658 set arm fallback-mode (arm|thumb|auto)
2659 show arm fallback-mode
2660 set arm force-mode (arm|thumb|auto)
2662 These commands control how ARM GDB determines whether instructions
2663 are ARM or Thumb. The default for both settings is auto, which uses
2664 the current CPSR value for instructions without symbols; previous
2665 versions of GDB behaved as if "set arm fallback-mode arm".
2667 set disable-randomization
2668 show disable-randomization
2669 Standalone programs run with the virtual address space randomization enabled
2670 by default on some platforms. This option keeps the addresses stable across
2671 multiple debugging sessions.
2675 Control whether other threads are stopped or not when some thread hits
2680 Requests that asynchronous execution is enabled in the target, if available.
2681 In this case, it's possible to resume target in the background, and interact
2682 with GDB while the target is running. "show target-async" displays the
2683 current state of asynchronous execution of the target.
2685 set target-wide-charset
2686 show target-wide-charset
2687 The target-wide-charset is the name of the character set that GDB
2688 uses when printing characters whose type is wchar_t.
2690 set tcp auto-retry (on|off)
2692 set tcp connect-timeout
2693 show tcp connect-timeout
2694 These commands allow GDB to retry failed TCP connections to a remote stub
2695 with a specified timeout period; this is useful if the stub is launched
2696 in parallel with GDB but may not be ready to accept connections immediately.
2698 set libthread-db-search-path
2699 show libthread-db-search-path
2700 Control list of directories which GDB will search for appropriate
2703 set schedule-multiple (on|off)
2704 show schedule-multiple
2705 Allow GDB to resume all threads of all processes or only threads of
2706 the current process.
2710 Use more aggressive caching for accesses to the stack. This improves
2711 performance of remote debugging (particularly backtraces) without
2712 affecting correctness.
2714 set interactive-mode (on|off|auto)
2715 show interactive-mode
2716 Control whether GDB runs in interactive mode (on) or not (off).
2717 When in interactive mode, GDB waits for the user to answer all
2718 queries. Otherwise, GDB does not wait and assumes the default
2719 answer. When set to auto (the default), GDB determines which
2720 mode to use based on the stdin settings.
2725 For program forks, this is replaced by the new more generic `info
2726 inferiors' command. To list checkpoints, you can still use the
2727 `info checkpoints' command, which was an alias for the `info forks'
2731 Replaced by the new `inferior' command. To switch between
2732 checkpoints, you can still use the `restart' command, which was an
2733 alias for the `fork' command.
2736 This is removed, since some targets don't have a notion of
2737 processes. To switch between processes, you can still use the
2738 `inferior' command using GDB's own inferior number.
2741 For program forks, this is replaced by the new more generic `kill
2742 inferior' command. To delete a checkpoint, you can still use the
2743 `delete checkpoint' command, which was an alias for the `delete
2747 For program forks, this is replaced by the new more generic `detach
2748 inferior' command. To detach a checkpoint, you can still use the
2749 `detach checkpoint' command, which was an alias for the `detach
2752 * New native configurations
2754 x86/x86_64 Darwin i[34567]86-*-darwin*
2756 x86_64 MinGW x86_64-*-mingw*
2760 Lattice Mico32 lm32-*
2761 x86 DICOS i[34567]86-*-dicos*
2762 x86_64 DICOS x86_64-*-dicos*
2765 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2766 (mingw32ce) debugging.
2772 These commands were actually not implemented on any target.
2774 *** Changes in GDB 6.8
2776 * New native configurations
2778 NetBSD/hppa hppa*-*netbsd*
2779 Xtensa GNU/Linux xtensa*-*-linux*
2783 NetBSD/hppa hppa*-*-netbsd*
2784 Xtensa GNU/Lunux xtensa*-*-linux*
2786 * Change in command line behavior -- corefiles vs. process ids.
2788 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2789 attaching to process NUMBER fails, GDB no longer attempts to open a
2790 core file named NUMBER. Attaching to a program using the -c option
2791 is no longer supported. Instead, use the '-p' or '--pid' options.
2793 * GDB can now be built as a native debugger for debugging Windows x86
2794 (mingw32) Portable Executable (PE) programs.
2796 * Pending breakpoints no longer change their number when their address
2799 * GDB now supports breakpoints with multiple locations,
2800 including breakpoints on C++ constructors, inside C++ templates,
2801 and in inlined functions.
2803 * GDB's ability to debug optimized code has been improved. GDB more
2804 accurately identifies function bodies and lexical blocks that occupy
2805 more than one contiguous range of addresses.
2807 * Target descriptions can now describe registers for PowerPC.
2809 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2810 registers on PowerPC targets.
2812 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2813 targets even when the libthread_db library is not available.
2815 * The GDB remote stub, gdbserver, now supports the new file transfer
2816 commands (remote put, remote get, and remote delete).
2818 * The GDB remote stub, gdbserver, now supports run and attach in
2819 extended-remote mode.
2821 * hppa*64*-*-hpux11* target broken
2822 The debugger is unable to start a program and fails with the following
2823 error: "Error trying to get information about dynamic linker".
2824 The gdb-6.7 release is also affected.
2826 * GDB now supports the --enable-targets= configure option to allow
2827 building a single GDB executable that supports multiple remote
2828 target architectures.
2830 * GDB now supports debugging C and C++ programs which use the
2831 Decimal Floating Point extension. In addition, the PowerPC target
2832 now has a set of pseudo-registers to inspect decimal float values
2833 stored in two consecutive float registers.
2835 * The -break-insert MI command can optionally create pending
2838 * Improved support for debugging Ada
2839 Many improvements to the Ada language support have been made. These
2841 - Better support for Ada2005 interface types
2842 - Improved handling of arrays and slices in general
2843 - Better support for Taft-amendment types
2844 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2846 - Improved command completion in Ada
2849 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2854 set print frame-arguments (all|scalars|none)
2855 show print frame-arguments
2856 The value of this variable can be changed to control which argument
2857 values should be printed by the debugger when displaying a frame.
2862 Transfer files to and from a remote target, and delete remote files.
2869 Transfer files to and from a remote target, and delete remote files.
2871 * New remote packets
2878 Open, close, read, write, and delete files on the remote system.
2881 Attach to an existing process on the remote system, in extended-remote
2885 Run a new process on the remote system, in extended-remote mode.
2887 *** Changes in GDB 6.7
2889 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2890 bfd, libiberty and opcodes, as revealed by static analysis donated by
2891 Coverity, Inc. (http://scan.coverity.com).
2893 * When looking up multiply-defined global symbols, GDB will now prefer the
2894 symbol definition in the current shared library if it was built using the
2895 -Bsymbolic linker option.
2897 * When the Text User Interface (TUI) is not configured, GDB will now
2898 recognize the -tui command-line option and print a message that the TUI
2901 * The GDB remote stub, gdbserver, now has lower overhead for high
2902 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2904 * GDB for MIPS targets now autodetects whether a remote target provides
2905 32-bit or 64-bit register values.
2907 * Support for C++ member pointers has been improved.
2909 * GDB now understands XML target descriptions, which specify the
2910 target's overall architecture. GDB can read a description from
2911 a local file or over the remote serial protocol.
2913 * Vectors of single-byte data use a new integer type which is not
2914 automatically displayed as character or string data.
2916 * The /s format now works with the print command. It displays
2917 arrays of single-byte integers and pointers to single-byte integers
2920 * Target descriptions can now describe target-specific registers,
2921 for architectures which have implemented the support (currently
2922 only ARM, M68K, and MIPS).
2924 * GDB and the GDB remote stub, gdbserver, now support the XScale
2927 * The GDB remote stub, gdbserver, has been updated to support
2928 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2929 has been rewritten to use the standard GDB remote protocol.
2931 * GDB can now step into C++ functions which are called through thunks.
2933 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2935 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2936 layout. It also supports a TextSeg= and DataSeg= response when only
2937 segment base addresses (rather than offsets) are available.
2939 * The /i format now outputs any trailing branch delay slot instructions
2940 immediately following the last instruction within the count specified.
2942 * The GDB remote protocol "T" stop reply packet now supports a
2943 "library" response. Combined with the new "qXfer:libraries:read"
2944 packet, this response allows GDB to debug shared libraries on targets
2945 where the operating system manages the list of loaded libraries (e.g.
2946 Windows and SymbianOS).
2948 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2949 (DLLs) on Windows and Windows CE targets.
2951 * GDB now supports a faster verification that a .debug file matches its binary
2952 according to its build-id signature, if the signature is present.
2958 Enable or disable hardware flow control (RTS/CTS) on the serial port
2959 when debugging using remote targets.
2961 set mem inaccessible-by-default
2962 show mem inaccessible-by-default
2963 If the target supplies a memory map, for instance via the remote
2964 protocol's "qXfer:memory-map:read" packet, setting this variable
2965 prevents GDB from accessing memory outside the memory map. This
2966 is useful for targets with memory mapped registers or which react
2967 badly to accesses of unmapped address space.
2969 set breakpoint auto-hw
2970 show breakpoint auto-hw
2971 If the target supplies a memory map, for instance via the remote
2972 protocol's "qXfer:memory-map:read" packet, setting this variable
2973 lets GDB use hardware breakpoints automatically for memory regions
2974 where it can not use software breakpoints. This covers both the
2975 "break" command and internal breakpoints used for other commands
2976 including "next" and "finish".
2979 catch exception unhandled
2980 Stop the program execution when Ada exceptions are raised.
2983 Stop the program execution when an Ada assertion failed.
2987 Set an alternate system root for target files. This is a more
2988 general version of "set solib-absolute-prefix", which is now
2989 an alias to "set sysroot".
2992 Provide extended SPU facility status information. This set of
2993 commands is available only when debugging the Cell/B.E. SPU
2996 * New native configurations
2998 OpenBSD/sh sh*-*openbsd*
3001 unset tdesc filename
3003 Use the specified local file as an XML target description, and do
3004 not query the target for its built-in description.
3008 OpenBSD/sh sh*-*-openbsd*
3009 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3010 Toshiba Media Processor mep-elf
3012 * New remote packets
3015 Ignore the specified signals; pass them directly to the debugged program
3016 without stopping other threads or reporting them to GDB.
3018 qXfer:features:read:
3019 Read an XML target description from the target, which describes its
3024 Read or write contents of an spufs file on the target system. These
3025 packets are available only on the Cell/B.E. SPU architecture.
3027 qXfer:libraries:read:
3028 Report the loaded shared libraries. Combined with new "T" packet
3029 response, this packet allows GDB to debug shared libraries on
3030 targets where the operating system manages the list of loaded
3031 libraries (e.g. Windows and SymbianOS).
3035 Support for these obsolete configurations has been removed.
3043 i[34567]86-*-lynxos*
3044 i[34567]86-*-netware*
3045 i[34567]86-*-sco3.2v5*
3046 i[34567]86-*-sco3.2v4*
3048 i[34567]86-*-sysv4.2*
3051 i[34567]86-*-unixware2*
3052 i[34567]86-*-unixware*
3061 * Other removed features
3068 Various m68k-only ROM monitors.
3075 Various Renesas ROM monitors and debugging interfaces for SH and
3080 Support for a Macraigor serial interface to on-chip debugging.
3081 GDB does not directly support the newer parallel or USB
3086 A debug information format. The predecessor to DWARF 2 and
3087 DWARF 3, which are still supported.
3089 Support for the HP aCC compiler on HP-UX/PA-RISC
3091 SOM-encapsulated symbolic debugging information, automatic
3092 invocation of pxdb, and the aCC custom C++ ABI. This does not
3093 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3094 with aCC can still be debugged on an assembly level.
3096 MIPS ".pdr" sections
3098 A MIPS-specific format used to describe stack frame layout
3099 in debugging information.
3103 GDB could work with an older version of Guile to debug
3104 the interpreter and Scheme programs running in it.
3106 set mips stack-arg-size
3107 set mips saved-gpreg-size
3109 Use "set mips abi" to control parameter passing for MIPS.
3111 *** Changes in GDB 6.6
3116 Cell Broadband Engine SPU spu-elf
3118 * GDB can now be configured as a cross-debugger targeting native Windows
3119 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3120 running on a Windows system over TCP/IP to debug Windows programs.
3122 * The GDB remote stub, gdbserver, has been updated to support Windows and
3123 Cygwin debugging. Both single-threaded and multi-threaded programs are
3126 * The "set trust-readonly-sections" command works again. This command was
3127 broken in GDB 6.3, 6.4, and 6.5.
3129 * The "load" command now supports writing to flash memory, if the remote
3130 stub provides the required support.
3132 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3133 longer requires symbolic debug information (e.g. DWARF-2).
3138 unset substitute-path
3139 show substitute-path
3140 Manage a list of substitution rules that GDB uses to rewrite the name
3141 of the directories where the sources are located. This can be useful
3142 for instance when the sources were moved to a different location
3143 between compilation and debugging.
3147 Print each CLI command as it is executed. Each command is prefixed with
3148 a number of `+' symbols representing the nesting depth.
3149 The source command now has a `-v' option to enable the same feature.
3153 The ARM Demon monitor support (RDP protocol, "target rdp").
3155 Kernel Object Display, an embedded debugging feature which only worked with
3156 an obsolete version of Cisco IOS.
3158 The 'set download-write-size' and 'show download-write-size' commands.
3160 * New remote packets
3163 Tell a stub about GDB client features, and request remote target features.
3164 The first feature implemented is PacketSize, which allows the target to
3165 specify the size of packets it can handle - to minimize the number of
3166 packets required and improve performance when connected to a remote
3170 Fetch an OS auxilliary vector from the remote stub. This packet is a
3171 more efficient replacement for qPart:auxv:read.
3173 qXfer:memory-map:read:
3174 Fetch a memory map from the remote stub, including information about
3175 RAM, ROM, and flash memory devices.
3180 Erase and program a flash memory device.
3182 * Removed remote packets
3185 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3186 used it, and only gdbserver implemented it.
3188 *** Changes in GDB 6.5
3192 Renesas M32C/M16C m32c-elf
3194 Morpho Technologies ms1 ms1-elf
3198 init-if-undefined Initialize a convenience variable, but
3199 only if it doesn't already have a value.
3201 The following commands are presently only implemented for native GNU/Linux:
3203 checkpoint Save a snapshot of the program state.
3205 restart <n> Return the program state to a
3206 previously saved state.
3208 info checkpoints List currently saved checkpoints.
3210 delete-checkpoint <n> Delete a previously saved checkpoint.
3212 set|show detach-on-fork Tell gdb whether to detach from a newly
3213 forked process, or to keep debugging it.
3215 info forks List forks of the user program that
3216 are available to be debugged.
3218 fork <n> Switch to debugging one of several
3219 forks of the user program that are
3220 available to be debugged.
3222 delete-fork <n> Delete a fork from the list of forks
3223 that are available to be debugged (and
3224 kill the forked process).
3226 detach-fork <n> Delete a fork from the list of forks
3227 that are available to be debugged (and
3228 allow the process to continue).
3232 Morpho Technologies ms2 ms1-elf
3234 * Improved Windows host support
3236 GDB now builds as a cross debugger hosted on i686-mingw32, including
3237 native console support, and remote communications using either
3238 network sockets or serial ports.
3240 * Improved Modula-2 language support
3242 GDB can now print most types in the Modula-2 syntax. This includes:
3243 basic types, set types, record types, enumerated types, range types,
3244 pointer types and ARRAY types. Procedure var parameters are correctly
3245 printed and hexadecimal addresses and character constants are also
3246 written in the Modula-2 syntax. Best results can be obtained by using
3247 GNU Modula-2 together with the -gdwarf-2 command line option.
3251 The ARM rdi-share module.
3253 The Netware NLM debug server.
3255 *** Changes in GDB 6.4
3257 * New native configurations
3259 OpenBSD/arm arm*-*-openbsd*
3260 OpenBSD/mips64 mips64-*-openbsd*
3264 Morpho Technologies ms1 ms1-elf
3266 * New command line options
3268 --batch-silent As for --batch, but totally silent.
3269 --return-child-result The debugger will exist with the same value
3270 the child (debugged) program exited with.
3271 --eval-command COMMAND, -ex COMMAND
3272 Execute a single GDB CLI command. This may be
3273 specified multiple times and in conjunction
3274 with the --command (-x) option.
3276 * Deprecated commands removed
3278 The following commands, that were deprecated in 2000, have been
3282 set|show arm disassembly-flavor set|show arm disassembler
3283 othernames set arm disassembler
3284 set|show remotedebug set|show debug remote
3285 set|show archdebug set|show debug arch
3286 set|show eventdebug set|show debug event
3289 * New BSD user-level threads support
3291 It is now possible to debug programs using the user-level threads
3292 library on OpenBSD and FreeBSD. Currently supported (target)
3295 FreeBSD/amd64 x86_64-*-freebsd*
3296 FreeBSD/i386 i386-*-freebsd*
3297 OpenBSD/i386 i386-*-openbsd*
3299 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3300 are not yet supported.
3302 * New support for Matsushita MN10300 w/sim added
3303 (Work in progress). mn10300-elf.
3305 * REMOVED configurations and files
3307 VxWorks and the XDR protocol *-*-vxworks
3308 Motorola MCORE mcore-*-*
3309 National Semiconductor NS32000 ns32k-*-*
3311 * New "set print array-indexes" command
3313 After turning this setting "on", GDB prints the index of each element
3314 when displaying arrays. The default is "off" to preserve the previous
3317 * VAX floating point support
3319 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3321 * User-defined command support
3323 In addition to using $arg0..$arg9 for argument passing, it is now possible
3324 to use $argc to determine now many arguments have been passed. See the
3325 section on user-defined commands in the user manual for more information.
3327 *** Changes in GDB 6.3:
3329 * New command line option
3331 GDB now accepts -l followed by a number to set the timeout for remote
3334 * GDB works with GCC -feliminate-dwarf2-dups
3336 GDB now supports a more compact representation of DWARF-2 debug
3337 information using DW_FORM_ref_addr references. These are produced
3338 by GCC with the option -feliminate-dwarf2-dups and also by some
3339 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3340 to use -feliminate-dwarf2-dups.
3342 * Internationalization
3344 When supported by the host system, GDB will be built with
3345 internationalization (libintl). The task of marking up the sources is
3346 continued, we're looking forward to our first translation.
3350 Initial support for debugging programs compiled with the GNAT
3351 implementation of the Ada programming language has been integrated
3352 into GDB. In this release, support is limited to expression evaluation.
3354 * New native configurations
3356 GNU/Linux/m32r m32r-*-linux-gnu
3360 GDB's remote protocol now includes support for the 'p' packet. This
3361 packet is used to fetch individual registers from a remote inferior.
3363 * END-OF-LIFE registers[] compatibility module
3365 GDB's internal register infrastructure has been completely rewritten.
3366 The new infrastructure making possible the implementation of key new
3367 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3370 GDB 6.3 will be the last release to include the the registers[]
3371 compatibility module that allowed out-of-date configurations to
3372 continue to work. This change directly impacts the following
3382 powerpc bdm protocol
3384 Unless there is activity to revive these configurations, they will be
3385 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3387 * OBSOLETE configurations and files
3389 Configurations that have been declared obsolete in this release have
3390 been commented out. Unless there is activity to revive these
3391 configurations, the next release of GDB will have their sources
3392 permanently REMOVED.
3401 *** Changes in GDB 6.2.1:
3403 * MIPS `break main; run' gave an heuristic-fence-post warning
3405 When attempting to run even a simple program, a warning about
3406 heuristic-fence-post being hit would be reported. This problem has
3409 * MIPS IRIX 'long double' crashed GDB
3411 When examining a long double variable, GDB would get a segmentation
3412 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3413 IRIX long double values).
3417 A bug in the VAX stack code was causing problems with the "next"
3418 command. This problem has been fixed.
3420 *** Changes in GDB 6.2:
3422 * Fix for ``many threads''
3424 On GNU/Linux systems that use the NPTL threads library, a program
3425 rapidly creating and deleting threads would confuse GDB leading to the
3428 ptrace: No such process.
3429 thread_db_get_info: cannot get thread info: generic error
3431 This problem has been fixed.
3433 * "-async" and "-noasync" options removed.
3435 Support for the broken "-noasync" option has been removed (it caused
3438 * New ``start'' command.
3440 This command runs the program until the begining of the main procedure.
3442 * New BSD Kernel Data Access Library (libkvm) interface
3444 Using ``target kvm'' it is now possible to debug kernel core dumps and
3445 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3446 platforms. Currently supported (native-only) configurations are:
3448 FreeBSD/amd64 x86_64-*-freebsd*
3449 FreeBSD/i386 i?86-*-freebsd*
3450 NetBSD/i386 i?86-*-netbsd*
3451 NetBSD/m68k m68*-*-netbsd*
3452 NetBSD/sparc sparc-*-netbsd*
3453 OpenBSD/amd64 x86_64-*-openbsd*
3454 OpenBSD/i386 i?86-*-openbsd*
3455 OpenBSD/m68k m68*-openbsd*
3456 OpenBSD/sparc sparc-*-openbsd*
3458 * Signal trampoline code overhauled
3460 Many generic problems with GDB's signal handling code have been fixed.
3461 These include: backtraces through non-contiguous stacks; recognition
3462 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3463 call; backtrace through a signal trampoline; step into and out of
3464 signal handlers; and single-stepping in the signal trampoline.
3466 Please note that kernel bugs are a limiting factor here. These
3467 features have been shown to work on an s390 GNU/Linux system that
3468 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3470 * Cygwin support for DWARF 2 added.
3472 * New native configurations
3474 GNU/Linux/hppa hppa*-*-linux*
3475 OpenBSD/hppa hppa*-*-openbsd*
3476 OpenBSD/m68k m68*-*-openbsd*
3477 OpenBSD/m88k m88*-*-openbsd*
3478 OpenBSD/powerpc powerpc-*-openbsd*
3479 NetBSD/vax vax-*-netbsd*
3480 OpenBSD/vax vax-*-openbsd*
3482 * END-OF-LIFE frame compatibility module
3484 GDB's internal frame infrastructure has been completely rewritten.
3485 The new infrastructure making it possible to support key new features
3486 including DWARF 2 Call Frame Information. To aid in the task of
3487 migrating old configurations to this new infrastructure, a
3488 compatibility module, that allowed old configurations to continue to
3489 work, was also included.
3491 GDB 6.2 will be the last release to include this frame compatibility
3492 module. This change directly impacts the following configurations:
3502 Unless there is activity to revive these configurations, they will be
3503 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3505 * REMOVED configurations and files
3507 Sun 3, running SunOS 3 m68*-*-sunos3*
3508 Sun 3, running SunOS 4 m68*-*-sunos4*
3509 Sun 2, running SunOS 3 m68000-*-sunos3*
3510 Sun 2, running SunOS 4 m68000-*-sunos4*
3511 Motorola 680x0 running LynxOS m68*-*-lynxos*
3512 AT&T 3b1/Unix pc m68*-att-*
3513 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3514 decstation mips-dec-* mips-little-*
3515 riscos mips-*-riscos* mips-*-sysv*
3516 sonymips mips-sony-*
3517 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3519 *** Changes in GDB 6.1.1:
3521 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3523 The TUI (Text-mode User Interface) is now built as part of a default
3524 GDB configuration. It is enabled by either selecting the TUI with the
3525 command line option "-i=tui" or by running the separate "gdbtui"
3526 program. For more information on the TUI, see the manual "Debugging
3529 * Pending breakpoint support (also included in GDB 6.1)
3531 Support has been added to allow you to specify breakpoints in shared
3532 libraries that have not yet been loaded. If a breakpoint location
3533 cannot be found, and the "breakpoint pending" option is set to auto,
3534 GDB queries you if you wish to make the breakpoint pending on a future
3535 shared-library load. If and when GDB resolves the breakpoint symbol,
3536 the pending breakpoint is removed as one or more regular breakpoints
3539 Pending breakpoints are very useful for GCJ Java debugging.
3541 * Fixed ISO-C build problems
3543 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3544 non ISO-C code that stopped them being built using a more strict ISO-C
3545 compiler (e.g., IBM's C compiler).
3547 * Fixed build problem on IRIX 5
3549 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3550 wasn't able to compile compile on an IRIX 5 system.
3552 * Added execute permission to gdb/gdbserver/configure
3554 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3555 permission. This bug would cause configure to fail on a number of
3556 systems (Solaris, IRIX). Ref: server/519.
3558 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3560 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3561 has been updated to use constant array sizes.
3563 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3565 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3566 its generated DWARF Call Frame Info. This encoding was causing GDB to
3567 panic, that panic has been fixed. Ref: gdb/1628.
3569 * Fixed a problem when examining parameters in shared library code.
3571 When examining parameters in optimized shared library code generated
3572 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3573 not available''. GDB now correctly displays the variable's value.
3575 *** Changes in GDB 6.1:
3577 * Removed --with-mmalloc
3579 Support for the mmalloc memory manager has been removed, as it
3580 conflicted with the internal gdb byte cache.
3582 * Changes in AMD64 configurations
3584 The AMD64 target now includes the %cs and %ss registers. As a result
3585 the AMD64 remote protocol has changed; this affects the floating-point
3586 and SSE registers. If you rely on those registers for your debugging,
3587 you should upgrade gdbserver on the remote side.
3589 * Revised SPARC target
3591 The SPARC target has been completely revised, incorporating the
3592 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3593 support for LynxOS and SunOS 4 has been dropped. Calling functions
3594 from within GDB on operating systems with a non-executable stack
3595 (Solaris, OpenBSD) now works.
3599 GDB has a new C++ demangler which does a better job on the mangled
3600 names generated by current versions of g++. It also runs faster, so
3601 with this and other changes gdb should now start faster on large C++
3604 * DWARF 2 Location Expressions
3606 GDB support for location expressions has been extended to support function
3607 arguments and frame bases. Older versions of GDB could crash when they
3610 * C++ nested types and namespaces
3612 GDB's support for nested types and namespaces in C++ has been
3613 improved, especially if you use the DWARF 2 debugging format. (This
3614 is the default for recent versions of GCC on most platforms.)
3615 Specifically, if you have a class "Inner" defined within a class or
3616 namespace "Outer", then GDB realizes that the class's name is
3617 "Outer::Inner", not simply "Inner". This should greatly reduce the
3618 frequency of complaints about not finding RTTI symbols. In addition,
3619 if you are stopped at inside of a function defined within a namespace,
3620 GDB modifies its name lookup accordingly.
3622 * New native configurations
3624 NetBSD/amd64 x86_64-*-netbsd*
3625 OpenBSD/amd64 x86_64-*-openbsd*
3626 OpenBSD/alpha alpha*-*-openbsd*
3627 OpenBSD/sparc sparc-*-openbsd*
3628 OpenBSD/sparc64 sparc64-*-openbsd*
3630 * New debugging protocols
3632 M32R with SDI protocol m32r-*-elf*
3634 * "set prompt-escape-char" command deleted.
3636 The command "set prompt-escape-char" has been deleted. This command,
3637 and its very obscure effet on GDB's prompt, was never documented,
3638 tested, nor mentioned in the NEWS file.
3640 * OBSOLETE configurations and files
3642 Configurations that have been declared obsolete in this release have
3643 been commented out. Unless there is activity to revive these
3644 configurations, the next release of GDB will have their sources
3645 permanently REMOVED.
3647 Sun 3, running SunOS 3 m68*-*-sunos3*
3648 Sun 3, running SunOS 4 m68*-*-sunos4*
3649 Sun 2, running SunOS 3 m68000-*-sunos3*
3650 Sun 2, running SunOS 4 m68000-*-sunos4*
3651 Motorola 680x0 running LynxOS m68*-*-lynxos*
3652 AT&T 3b1/Unix pc m68*-att-*
3653 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3654 decstation mips-dec-* mips-little-*
3655 riscos mips-*-riscos* mips-*-sysv*
3656 sonymips mips-sony-*
3657 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3659 * REMOVED configurations and files
3661 SGI Irix-4.x mips-sgi-irix4 or iris4
3662 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3663 Z8000 simulator z8k-zilog-none or z8ksim
3664 Matsushita MN10200 w/simulator mn10200-*-*
3665 H8/500 simulator h8500-hitachi-hms or h8500hms
3666 HP/PA running BSD hppa*-*-bsd*
3667 HP/PA running OSF/1 hppa*-*-osf*
3668 HP/PA Pro target hppa*-*-pro*
3669 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3670 386BSD i[3456]86-*-bsd*
3671 Sequent family i[3456]86-sequent-sysv4*
3672 i[3456]86-sequent-sysv*
3673 i[3456]86-sequent-bsd*
3674 SPARC running LynxOS sparc-*-lynxos*
3675 SPARC running SunOS 4 sparc-*-sunos4*
3676 Tsqware Sparclet sparclet-*-*
3677 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3679 *** Changes in GDB 6.0:
3683 Support for debugging the Objective-C programming language has been
3684 integrated into GDB.
3686 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3688 DWARF 2's Call Frame Information makes available compiler generated
3689 information that more exactly describes the program's run-time stack.
3690 By using this information, GDB is able to provide more robust stack
3693 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3694 have been updated to use a new backtrace mechanism which includes
3695 DWARF 2 CFI support.
3699 GDB's remote protocol has been extended to include support for hosted
3700 file I/O (where the remote target uses GDB's file system). See GDB's
3701 remote protocol documentation for details.
3703 * All targets using the new architecture framework.
3705 All of GDB's targets have been updated to use the new internal
3706 architecture framework. The way is now open for future GDB releases
3707 to include cross-architecture native debugging support (i386 on amd64,
3710 * GNU/Linux's Thread Local Storage (TLS)
3712 GDB now includes support for for the GNU/Linux implementation of
3713 per-thread variables.
3715 * GNU/Linux's Native POSIX Thread Library (NPTL)
3717 GDB's thread code has been updated to work with either the new
3718 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3720 * Separate debug info.
3722 GDB, in conjunction with BINUTILS, now supports a mechanism for
3723 automatically loading debug information from a separate file. Instead
3724 of shipping full debug and non-debug versions of system libraries,
3725 system integrators can now instead ship just the stripped libraries
3726 and optional debug files.
3728 * DWARF 2 Location Expressions
3730 DWARF 2 Location Expressions allow the compiler to more completely
3731 describe the location of variables (even in optimized code) to the
3734 GDB now includes preliminary support for location expressions (support
3735 for DW_OP_piece is still missing).
3739 A number of long standing bugs that caused GDB to die while starting a
3740 Java application have been fixed. GDB's Java support is now
3741 considered "useable".
3743 * GNU/Linux support for fork, vfork, and exec.
3745 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3746 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3749 * GDB supports logging output to a file
3751 There are two new commands, "set logging" and "show logging", which can be
3752 used to capture GDB's output to a file.
3754 * The meaning of "detach" has changed for gdbserver
3756 The "detach" command will now resume the application, as documented. To
3757 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3760 * d10v, m68hc11 `regs' command deprecated
3762 The `info registers' command has been updated so that it displays the
3763 registers using a format identical to the old `regs' command.
3767 A new command, "maint set profile on/off", has been added. This command can
3768 be used to enable or disable profiling while running GDB, to profile a
3769 session or a set of commands. In addition there is a new configure switch,
3770 "--enable-profiling", which will cause GDB to be compiled with profiling
3771 data, for more informative profiling results.
3773 * Default MI syntax changed to "mi2".
3775 The default MI (machine interface) syntax, enabled by the command line
3776 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3777 "mi1", can be enabled by specifying the option "-i=mi1".
3779 Support for the original "mi0" syntax (included in GDB 5.0) has been
3782 Fix for gdb/192: removed extraneous space when displaying frame level.
3783 Fix for gdb/672: update changelist is now output in mi list format.
3784 Fix for gdb/702: a -var-assign that updates the value now shows up
3785 in a subsequent -var-update.
3787 * New native configurations.
3789 FreeBSD/amd64 x86_64-*-freebsd*
3791 * Multi-arched targets.
3793 HP/PA HPUX11 hppa*-*-hpux*
3794 Renesas M32R/D w/simulator m32r-*-elf*
3796 * OBSOLETE configurations and files
3798 Configurations that have been declared obsolete in this release have
3799 been commented out. Unless there is activity to revive these
3800 configurations, the next release of GDB will have their sources
3801 permanently REMOVED.
3803 Z8000 simulator z8k-zilog-none or z8ksim
3804 Matsushita MN10200 w/simulator mn10200-*-*
3805 H8/500 simulator h8500-hitachi-hms or h8500hms
3806 HP/PA running BSD hppa*-*-bsd*
3807 HP/PA running OSF/1 hppa*-*-osf*
3808 HP/PA Pro target hppa*-*-pro*
3809 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3810 Sequent family i[3456]86-sequent-sysv4*
3811 i[3456]86-sequent-sysv*
3812 i[3456]86-sequent-bsd*
3813 Tsqware Sparclet sparclet-*-*
3814 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3816 * REMOVED configurations and files
3819 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3820 IBM AIX PS/2 i[3456]86-*-aix
3821 i386 running Mach 3.0 i[3456]86-*-mach3*
3822 i386 running Mach i[3456]86-*-mach*
3823 i386 running OSF/1 i[3456]86-*osf1mk*
3824 HP/Apollo 68k Family m68*-apollo*-sysv*,
3826 m68*-hp-bsd*, m68*-hp-hpux*
3827 Argonaut Risc Chip (ARC) arc-*-*
3828 Mitsubishi D30V d30v-*-*
3829 Fujitsu FR30 fr30-*-elf*
3830 OS/9000 i[34]86-*-os9k
3831 I960 with MON960 i960-*-coff
3833 * MIPS $fp behavior changed
3835 The convenience variable $fp, for the MIPS, now consistently returns
3836 the address of the current frame's base. Previously, depending on the
3837 context, $fp could refer to either $sp or the current frame's base
3838 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3839 The GNU Source-Level Debugger''.
3841 *** Changes in GDB 5.3:
3843 * GNU/Linux shared library multi-threaded performance improved.
3845 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3846 `/proc', in preference to `ptrace' for memory reads. This may result
3847 in an improvement in the start-up time of multi-threaded, shared
3848 library applications when run under GDB. One GDB user writes: ``loads
3849 shared libs like mad''.
3851 * ``gdbserver'' now supports multi-threaded applications on some targets
3853 Support for debugging multi-threaded applications which use
3854 the GNU/Linux LinuxThreads package has been added for
3855 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3856 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3858 * GDB now supports C/C++ preprocessor macros.
3860 GDB now expands preprocessor macro invocations in C/C++ expressions,
3861 and provides various commands for showing macro definitions and how
3864 The new command `macro expand EXPRESSION' expands any macro
3865 invocations in expression, and shows the result.
3867 The new command `show macro MACRO-NAME' shows the definition of the
3868 macro named MACRO-NAME, and where it was defined.
3870 Most compilers don't include information about macros in the debugging
3871 information by default. In GCC 3.1, for example, you need to compile
3872 your program with the options `-gdwarf-2 -g3'. If the macro
3873 information is present in the executable, GDB will read it.
3875 * Multi-arched targets.
3877 DEC Alpha (partial) alpha*-*-*
3878 DEC VAX (partial) vax-*-*
3880 National Semiconductor NS32000 (partial) ns32k-*-*
3881 Motorola 68000 (partial) m68k-*-*
3882 Motorola MCORE mcore-*-*
3886 Fujitsu FRV architecture added by Red Hat frv*-*-*
3889 * New native configurations
3891 Alpha NetBSD alpha*-*-netbsd*
3892 SH NetBSD sh*-*-netbsdelf*
3893 MIPS NetBSD mips*-*-netbsd*
3894 UltraSPARC NetBSD sparc64-*-netbsd*
3896 * OBSOLETE configurations and files
3898 Configurations that have been declared obsolete in this release have
3899 been commented out. Unless there is activity to revive these
3900 configurations, the next release of GDB will have their sources
3901 permanently REMOVED.
3903 Mitsubishi D30V d30v-*-*
3904 OS/9000 i[34]86-*-os9k
3905 IBM AIX PS/2 i[3456]86-*-aix
3906 Fujitsu FR30 fr30-*-elf*
3907 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3908 Argonaut Risc Chip (ARC) arc-*-*
3909 i386 running Mach 3.0 i[3456]86-*-mach3*
3910 i386 running Mach i[3456]86-*-mach*
3911 i386 running OSF/1 i[3456]86-*osf1mk*
3912 HP/Apollo 68k Family m68*-apollo*-sysv*,
3914 m68*-hp-bsd*, m68*-hp-hpux*
3915 I960 with MON960 i960-*-coff
3917 * OBSOLETE languages
3919 CHILL, a Pascal like language used by telecommunications companies.
3921 * REMOVED configurations and files
3923 AMD 29k family via UDI a29k-amd-udi, udi29k
3924 A29K VxWorks a29k-*-vxworks
3925 AMD 29000 embedded, using EBMON a29k-none-none
3926 AMD 29000 embedded with COFF a29k-none-coff
3927 AMD 29000 embedded with a.out a29k-none-aout
3929 testsuite/gdb.hp/gdb.threads-hp/ directory
3931 * New command "set max-user-call-depth <nnn>"
3933 This command allows the user to limit the call depth of user-defined
3934 commands. The default is 1024.
3936 * Changes in FreeBSD/i386 native debugging.
3938 Support for the "generate-core-file" has been added.
3940 * New commands "dump", "append", and "restore".
3942 These commands allow data to be copied from target memory
3943 to a bfd-format or binary file (dump and append), and back
3944 from a file into memory (restore).
3946 * Improved "next/step" support on multi-processor Alpha Tru64.
3948 The previous single-step mechanism could cause unpredictable problems,
3949 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3950 of a software single-step mechanism prevents this.
3952 *** Changes in GDB 5.2.1:
3960 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3961 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3962 Fix, by Joel Brobecker imported from mainline.
3964 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3965 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3966 Fix, by Fred Fish, imported from mainline.
3968 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3969 Surprisingly enough, it works now.
3970 By Michal Ludvig, imported from mainline.
3972 i386 hardware watchpoint support:
3973 avoid misses on second run for some targets.
3974 By Pierre Muller, imported from mainline.
3976 *** Changes in GDB 5.2:
3978 * New command "set trust-readonly-sections on[off]".
3980 This command is a hint that tells gdb that read-only sections
3981 really are read-only (ie. that their contents will not change).
3982 In this mode, gdb will go to the object file rather than the
3983 target to read memory from read-only sections (such as ".text").
3984 This can be a significant performance improvement on some
3985 (notably embedded) targets.
3987 * New command "generate-core-file" (or "gcore").
3989 This new gdb command allows the user to drop a core file of the child
3990 process state at any time. So far it's been implemented only for
3991 GNU/Linux and Solaris, but should be relatively easily ported to other
3992 hosts. Argument is core file name (defaults to core.<pid>).
3994 * New command line option
3996 GDB now accepts --pid or -p followed by a process id.
3998 * Change in command line behavior -- corefiles vs. process ids.
4000 There is a subtle behavior in the way in which GDB handles
4001 command line arguments. The first non-flag argument is always
4002 a program to debug, but the second non-flag argument may either
4003 be a corefile or a process id. Previously, GDB would attempt to
4004 open the second argument as a corefile, and if that failed, would
4005 issue a superfluous error message and then attempt to attach it as
4006 a process. Now, if the second argument begins with a non-digit,
4007 it will be treated as a corefile. If it begins with a digit,
4008 GDB will attempt to attach it as a process, and if no such process
4009 is found, will then attempt to open it as a corefile.
4011 * Changes in ARM configurations.
4013 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4014 configuration is fully multi-arch.
4016 * New native configurations
4018 ARM NetBSD arm*-*-netbsd*
4019 x86 OpenBSD i[3456]86-*-openbsd*
4020 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4021 Sparc64 running FreeBSD sparc64-*-freebsd*
4025 Sanyo XStormy16 xstormy16-elf
4027 * OBSOLETE configurations and files
4029 Configurations that have been declared obsolete in this release have
4030 been commented out. Unless there is activity to revive these
4031 configurations, the next release of GDB will have their sources
4032 permanently REMOVED.
4034 AMD 29k family via UDI a29k-amd-udi, udi29k
4035 A29K VxWorks a29k-*-vxworks
4036 AMD 29000 embedded, using EBMON a29k-none-none
4037 AMD 29000 embedded with COFF a29k-none-coff
4038 AMD 29000 embedded with a.out a29k-none-aout
4040 testsuite/gdb.hp/gdb.threads-hp/ directory
4042 * REMOVED configurations and files
4044 TI TMS320C80 tic80-*-*
4046 PowerPC Solaris powerpcle-*-solaris*
4047 PowerPC Windows NT powerpcle-*-cygwin32
4048 PowerPC Netware powerpc-*-netware*
4049 Harris/CXUX m88k m88*-harris-cxux*
4050 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4051 ns32k-utek-sysv* ns32k-utek-*
4052 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4053 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4054 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4055 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4056 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4058 * Changes to command line processing
4060 The new `--args' feature can be used to specify command-line arguments
4061 for the inferior from gdb's command line.
4063 * Changes to key bindings
4065 There is a new `operate-and-get-next' function bound to `C-o'.
4067 *** Changes in GDB 5.1.1
4069 Fix compile problem on DJGPP.
4071 Fix a problem with floating-point registers on the i386 being
4074 Fix to stop GDB crashing on .debug_str debug info.
4076 Numerous documentation fixes.
4078 Numerous testsuite fixes.
4080 *** Changes in GDB 5.1:
4082 * New native configurations
4084 Alpha FreeBSD alpha*-*-freebsd*
4085 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4086 MIPS GNU/Linux mips*-*-linux*
4087 MIPS SGI Irix 6.x mips*-sgi-irix6*
4088 ia64 AIX ia64-*-aix*
4089 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4093 Motorola 68HC11 and 68HC12 m68hc11-elf
4095 UltraSparc running GNU/Linux sparc64-*-linux*
4097 * OBSOLETE configurations and files
4099 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4100 Harris/CXUX m88k m88*-harris-cxux*
4101 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4102 ns32k-utek-sysv* ns32k-utek-*
4103 TI TMS320C80 tic80-*-*
4105 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4106 PowerPC Solaris powerpcle-*-solaris*
4107 PowerPC Windows NT powerpcle-*-cygwin32
4108 PowerPC Netware powerpc-*-netware*
4109 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4110 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4111 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4112 Apple Macintosh (MPW) host N/A
4114 stuff.c (Program to stuff files into a specially prepared space in kdb)
4115 kdb-start.c (Main loop for the standalone kernel debugger)
4117 Configurations that have been declared obsolete in this release have
4118 been commented out. Unless there is activity to revive these
4119 configurations, the next release of GDB will have their sources
4120 permanently REMOVED.
4122 * REMOVED configurations and files
4124 Altos 3068 m68*-altos-*
4125 Convex c1-*-*, c2-*-*
4127 ARM RISCix arm-*-* (as host)
4131 * GDB has been converted to ISO C.
4133 GDB's source code has been converted to ISO C. In particular, the
4134 sources are fully protoized, and rely on standard headers being
4139 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4141 * The MI enabled by default.
4143 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4144 revised and enabled by default. Packages which use GDB as a debugging
4145 engine behind a UI or another front end are encouraged to switch to
4146 using the GDB/MI interface, instead of the old annotations interface
4147 which is now deprecated.
4149 * Support for debugging Pascal programs.
4151 GDB now includes support for debugging Pascal programs. The following
4152 main features are supported:
4154 - Pascal-specific data types such as sets;
4156 - automatic recognition of Pascal sources based on file-name
4159 - Pascal-style display of data types, variables, and functions;
4161 - a Pascal expression parser.
4163 However, some important features are not yet supported.
4165 - Pascal string operations are not supported at all;
4167 - there are some problems with boolean types;
4169 - Pascal type hexadecimal constants are not supported
4170 because they conflict with the internal variables format;
4172 - support for Pascal objects and classes is not full yet;
4174 - unlike Pascal, GDB is case-sensitive for symbol names.
4176 * Changes in completion.
4178 Commands such as `shell', `run' and `set args', which pass arguments
4179 to inferior programs, now complete on file names, similar to what
4180 users expect at the shell prompt.
4182 Commands which accept locations, such as `disassemble', `print',
4183 `breakpoint', `until', etc. now complete on filenames as well as
4184 program symbols. Thus, if you type "break foob TAB", and the source
4185 files linked into the programs include `foobar.c', that file name will
4186 be one of the candidates for completion. However, file names are not
4187 considered for completion after you typed a colon that delimits a file
4188 name from a name of a function in that file, as in "break foo.c:bar".
4190 `set demangle-style' completes on available demangling styles.
4192 * New platform-independent commands:
4194 It is now possible to define a post-hook for a command as well as a
4195 hook that runs before the command. For more details, see the
4196 documentation of `hookpost' in the GDB manual.
4198 * Changes in GNU/Linux native debugging.
4200 Support for debugging multi-threaded programs has been completely
4201 revised for all platforms except m68k and sparc. You can now debug as
4202 many threads as your system allows you to have.
4204 Attach/detach is supported for multi-threaded programs.
4206 Support for SSE registers was added for x86. This doesn't work for
4207 multi-threaded programs though.
4209 * Changes in MIPS configurations.
4211 Multi-arch support is enabled for all MIPS configurations.
4213 GDB can now be built as native debugger on SGI Irix 6.x systems for
4214 debugging n32 executables. (Debugging 64-bit executables is not yet
4217 * Unified support for hardware watchpoints in all x86 configurations.
4219 Most (if not all) native x86 configurations support hardware-assisted
4220 breakpoints and watchpoints in a unified manner. This support
4221 implements debug register sharing between watchpoints, which allows to
4222 put a virtually infinite number of watchpoints on the same address,
4223 and also supports watching regions up to 16 bytes with several debug
4226 The new maintenance command `maintenance show-debug-regs' toggles
4227 debugging print-outs in functions that insert, remove, and test
4228 watchpoints and hardware breakpoints.
4230 * Changes in the DJGPP native configuration.
4232 New command ``info dos sysinfo'' displays assorted information about
4233 the CPU, OS, memory, and DPMI server.
4235 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4236 display information about segment descriptors stored in GDT, LDT, and
4239 New commands ``info dos pde'' and ``info dos pte'' display entries
4240 from Page Directory and Page Tables (for now works with CWSDPMI only).
4241 New command ``info dos address-pte'' displays the Page Table entry for
4242 a given linear address.
4244 GDB can now pass command lines longer than 126 characters to the
4245 program being debugged (requires an update to the libdbg.a library
4246 which is part of the DJGPP development kit).
4248 DWARF2 debug info is now supported.
4250 It is now possible to `step' and `next' through calls to `longjmp'.
4252 * Changes in documentation.
4254 All GDB documentation was converted to GFDL, the GNU Free
4255 Documentation License.
4257 Tracepoints-related commands are now fully documented in the GDB
4260 TUI, the Text-mode User Interface, is now documented in the manual.
4262 Tracepoints-related commands are now fully documented in the GDB
4265 The "GDB Internals" manual now has an index. It also includes
4266 documentation of `ui_out' functions, GDB coding standards, x86
4267 hardware watchpoints, and memory region attributes.
4269 * GDB's version number moved to ``version.in''
4271 The Makefile variable VERSION has been replaced by the file
4272 ``version.in''. People creating GDB distributions should update the
4273 contents of this file.
4277 GUD support is now a standard part of the EMACS distribution.
4279 *** Changes in GDB 5.0:
4281 * Improved support for debugging FP programs on x86 targets
4283 Unified and much-improved support for debugging floating-point
4284 programs on all x86 targets. In particular, ``info float'' now
4285 displays the FP registers in the same format on all x86 targets, with
4286 greater level of detail.
4288 * Improvements and bugfixes in hardware-assisted watchpoints
4290 It is now possible to watch array elements, struct members, and
4291 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4292 on x86 targets no longer erroneously trigger when the address is
4295 * Improvements in the native DJGPP version of GDB
4297 The distribution now includes all the scripts and auxiliary files
4298 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4299 machines ``out of the box''.
4301 The DJGPP version can now debug programs that use signals. It is
4302 possible to catch signals that happened in the debuggee, deliver
4303 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4304 would kill the program being debugged.) Programs that hook hardware
4305 interrupts (keyboard, timer, etc.) can also be debugged.
4307 It is now possible to debug DJGPP programs that redirect their
4308 standard handles or switch them to raw (as opposed to cooked) mode, or
4309 even close them. The command ``run < foo > bar'' works as expected,
4310 and ``info terminal'' reports useful information about the debuggee's
4311 terminal, including raw/cooked mode, redirection, etc.
4313 The DJGPP version now uses termios functions for console I/O, which
4314 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4317 DOS-style file names with drive letters are now fully supported by
4320 It is now possible to debug DJGPP programs that switch their working
4321 directory. It is also possible to rerun the debuggee any number of
4322 times without restarting GDB; thus, you can use the same setup,
4323 breakpoints, etc. for many debugging sessions.
4325 * New native configurations
4327 ARM GNU/Linux arm*-*-linux*
4328 PowerPC GNU/Linux powerpc-*-linux*
4332 Motorola MCore mcore-*-*
4333 x86 VxWorks i[3456]86-*-vxworks*
4334 PowerPC VxWorks powerpc-*-vxworks*
4335 TI TMS320C80 tic80-*-*
4337 * OBSOLETE configurations
4339 Altos 3068 m68*-altos-*
4340 Convex c1-*-*, c2-*-*
4342 ARM RISCix arm-*-* (as host)
4345 Configurations that have been declared obsolete will be commented out,
4346 but the code will be left in place. If there is no activity to revive
4347 these configurations before the next release of GDB, the sources will
4348 be permanently REMOVED.
4350 * Gould support removed
4352 Support for the Gould PowerNode and NP1 has been removed.
4354 * New features for SVR4
4356 On SVR4 native platforms (such as Solaris), if you attach to a process
4357 without first loading a symbol file, GDB will now attempt to locate and
4358 load symbols from the running process's executable file.
4360 * Many C++ enhancements
4362 C++ support has been greatly improved. Overload resolution now works properly
4363 in almost all cases. RTTI support is on the way.
4365 * Remote targets can connect to a sub-program
4367 A popen(3) style serial-device has been added. This device starts a
4368 sub-process (such as a stand-alone simulator) and then communicates
4369 with that. The sub-program to run is specified using the syntax
4370 ``|<program> <args>'' vis:
4372 (gdb) set remotedebug 1
4373 (gdb) target extended-remote |mn10300-elf-sim program-args
4375 * MIPS 64 remote protocol
4377 A long standing bug in the mips64 remote protocol where by GDB
4378 expected certain 32 bit registers (ex SR) to be transfered as 32
4379 instead of 64 bits has been fixed.
4381 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4382 added to provide backward compatibility with older versions of GDB.
4384 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4386 The command ``set remotebinarydownload'' command has been replaced by
4387 ``set remote X-packet''. Other commands in ``set remote'' family
4388 include ``set remote P-packet''.
4390 * Breakpoint commands accept ranges.
4392 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4393 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4394 ``tracepoint passcount'' also accepts a range of tracepoints.
4396 * ``apropos'' command added.
4398 The ``apropos'' command searches through command names and
4399 documentation strings, printing out matches, making it much easier to
4400 try to find a command that does what you are looking for.
4404 A new machine oriented interface (MI) has been added to GDB. This
4405 interface is designed for debug environments running GDB as a separate
4406 process. This is part of the long term libGDB project. See the
4407 "GDB/MI" chapter of the GDB manual for further information. It can be
4408 enabled by configuring with:
4410 .../configure --enable-gdbmi
4412 *** Changes in GDB-4.18:
4414 * New native configurations
4416 HP-UX 10.20 hppa*-*-hpux10.20
4417 HP-UX 11.x hppa*-*-hpux11.0*
4418 M68K GNU/Linux m68*-*-linux*
4422 Fujitsu FR30 fr30-*-elf*
4423 Intel StrongARM strongarm-*-*
4424 Mitsubishi D30V d30v-*-*
4426 * OBSOLETE configurations
4428 Gould PowerNode, NP1 np1-*-*, pn-*-*
4430 Configurations that have been declared obsolete will be commented out,
4431 but the code will be left in place. If there is no activity to revive
4432 these configurations before the next release of GDB, the sources will
4433 be permanently REMOVED.
4437 As a compatibility experiment, GDB's source files buildsym.h and
4438 buildsym.c have been converted to pure standard C, no longer
4439 containing any K&R compatibility code. We believe that all systems in
4440 use today either come with a standard C compiler, or have a GCC port
4441 available. If this is not true, please report the affected
4442 configuration to bug-gdb@gnu.org immediately. See the README file for
4443 information about getting a standard C compiler if you don't have one
4448 GDB now uses readline 2.2.
4450 * set extension-language
4452 You can now control the mapping between filename extensions and source
4453 languages by using the `set extension-language' command. For instance,
4454 you can ask GDB to treat .c files as C++ by saying
4455 set extension-language .c c++
4456 The command `info extensions' lists all of the recognized extensions
4457 and their associated languages.
4459 * Setting processor type for PowerPC and RS/6000
4461 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4462 you can use the `set processor' command to specify what variant of the
4463 PowerPC family you are debugging. The command
4467 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4468 following PowerPC and RS6000 variants:
4470 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4471 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4473 403GC IBM PowerPC 403GC
4474 505 Motorola PowerPC 505
4475 860 Motorola PowerPC 860 or 850
4476 601 Motorola PowerPC 601
4477 602 Motorola PowerPC 602
4478 603 Motorola/IBM PowerPC 603 or 603e
4479 604 Motorola PowerPC 604 or 604e
4480 750 Motorola/IBM PowerPC 750 or 750
4482 At the moment, this command just tells GDB what to name the
4483 special-purpose processor registers. Since almost all the affected
4484 registers are inaccessible to user-level programs, this command is
4485 only useful for remote debugging in its present form.
4489 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4490 more extensive support for HP-UX. Added features include shared
4491 library support, kernel threads and hardware watchpoints for 11.00,
4492 support for HP's ANSI C and C++ compilers, and a compatibility mode
4493 for xdb and dbx commands.
4497 HP's donation includes the new concept of catchpoints, which is a
4498 generalization of the old catch command. On HP-UX, it is now possible
4499 to catch exec, fork, and vfork, as well as library loading.
4501 This means that the existing catch command has changed; its first
4502 argument now specifies the type of catch to be set up. See the
4503 output of "help catch" for a list of catchpoint types.
4505 * Debugging across forks
4507 On HP-UX, you can choose which process to debug when a fork() happens
4512 HP has donated a curses-based terminal user interface (TUI). To get
4513 it, build with --enable-tui. Although this can be enabled for any
4514 configuration, at present it only works for native HP debugging.
4516 * GDB remote protocol additions
4518 A new protocol packet 'X' that writes binary data is now available.
4519 Default behavior is to try 'X', then drop back to 'M' if the stub
4520 fails to respond. The settable variable `remotebinarydownload'
4521 allows explicit control over the use of 'X'.
4523 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4524 full 64-bit address. The command
4526 set remoteaddresssize 32
4528 can be used to revert to the old behaviour. For existing remote stubs
4529 the change should not be noticed, as the additional address information
4532 In order to assist in debugging stubs, you may use the maintenance
4533 command `packet' to send any text string to the stub. For instance,
4535 maint packet heythere
4537 sends the packet "$heythere#<checksum>". Note that it is very easy to
4538 disrupt a debugging session by sending the wrong packet at the wrong
4541 The compare-sections command allows you to compare section data on the
4542 target to what is in the executable file without uploading or
4543 downloading, by comparing CRC checksums.
4545 * Tracing can collect general expressions
4547 You may now collect general expressions at tracepoints. This requires
4548 further additions to the target-side stub; see tracepoint.c and
4549 doc/agentexpr.texi for further details.
4551 * mask-address variable for Mips
4553 For Mips targets, you may control the zeroing of the upper 32 bits of
4554 a 64-bit address by entering `set mask-address on'. This is mainly
4555 of interest to users of embedded R4xxx and R5xxx processors.
4557 * Higher serial baud rates
4559 GDB's serial code now allows you to specify baud rates 57600, 115200,
4560 230400, and 460800 baud. (Note that your host system may not be able
4561 to achieve all of these rates.)
4565 The i960 configuration now includes an initial implementation of a
4566 builtin simulator, contributed by Jim Wilson.
4569 *** Changes in GDB-4.17:
4571 * New native configurations
4573 Alpha GNU/Linux alpha*-*-linux*
4574 Unixware 2.x i[3456]86-unixware2*
4575 Irix 6.x mips*-sgi-irix6*
4576 PowerPC GNU/Linux powerpc-*-linux*
4577 PowerPC Solaris powerpcle-*-solaris*
4578 Sparc GNU/Linux sparc-*-linux*
4579 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4583 Argonaut Risc Chip (ARC) arc-*-*
4584 Hitachi H8/300S h8300*-*-*
4585 Matsushita MN10200 w/simulator mn10200-*-*
4586 Matsushita MN10300 w/simulator mn10300-*-*
4587 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4588 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4589 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4590 Mitsubishi D10V w/simulator d10v-*-*
4591 Mitsubishi M32R/D w/simulator m32r-*-elf*
4592 Tsqware Sparclet sparclet-*-*
4593 NEC V850 w/simulator v850-*-*
4595 * New debugging protocols
4597 ARM with RDI protocol arm*-*-*
4598 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4599 DDB and LSI variants of PMON protocol mips*-*-*
4600 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4601 PowerPC with SDS protocol powerpc{,le}-*-eabi
4602 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4606 All configurations can now understand and use the DWARF 2 debugging
4607 format. The choice is automatic, if the symbol file contains DWARF 2
4612 GDB now includes basic Java language support. This support is
4613 only useful with Java compilers that produce native machine code.
4615 * solib-absolute-prefix and solib-search-path
4617 For SunOS and SVR4 shared libraries, you may now set the prefix for
4618 loading absolute shared library symbol files, and the search path for
4619 locating non-absolute shared library symbol files.
4621 * Live range splitting
4623 GDB can now effectively debug code for which GCC has performed live
4624 range splitting as part of its optimization. See gdb/doc/LRS for
4625 more details on the expected format of the stabs information.
4629 GDB's support for the GNU Hurd, including thread debugging, has been
4630 updated to work with current versions of the Hurd.
4634 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4635 instruction set. ARM GDB automatically detects when Thumb
4636 instructions are in use, and adjusts disassembly and backtracing
4641 GDB's MIPS target configurations now handle the MIP16 16-bit
4646 GDB now includes support for overlays; if an executable has been
4647 linked such that multiple sections are based at the same address, GDB
4648 will decide which section to use for symbolic info. You can choose to
4649 control the decision manually, using overlay commands, or implement
4650 additional target-side support and use "overlay load-target" to bring
4651 in the overlay mapping. Do "help overlay" for more detail.
4655 The command "info symbol <address>" displays information about
4656 the symbol at the specified address.
4660 The standard remote protocol now includes an extension that allows
4661 asynchronous collection and display of trace data. This requires
4662 extensive support in the target-side debugging stub. Tracing mode
4663 includes a new interaction mode in GDB and new commands: see the
4664 file tracepoint.c for more details.
4668 Configurations for embedded MIPS now include a simulator contributed
4669 by Cygnus Solutions. The simulator supports the instruction sets
4670 of most MIPS variants.
4674 Sparc configurations may now include the ERC32 simulator contributed
4675 by the European Space Agency. The simulator is not built into
4676 Sparc targets by default; configure with --enable-sim to include it.
4680 For target configurations that may include multiple variants of a
4681 basic architecture (such as MIPS and SH), you may now set the
4682 architecture explicitly. "set arch" sets, "info arch" lists
4683 the possible architectures.
4685 *** Changes in GDB-4.16:
4687 * New native configurations
4689 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4690 M68K NetBSD m68k-*-netbsd*
4691 PowerPC AIX 4.x powerpc-*-aix*
4692 PowerPC MacOS powerpc-*-macos*
4693 PowerPC Windows NT powerpcle-*-cygwin32
4694 RS/6000 AIX 4.x rs6000-*-aix4*
4698 ARM with RDP protocol arm-*-*
4699 I960 with MON960 i960-*-coff
4700 MIPS VxWorks mips*-*-vxworks*
4701 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4702 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4704 Matra Sparclet sparclet-*-*
4708 The powerpc-eabi configuration now includes the PSIM simulator,
4709 contributed by Andrew Cagney, with assistance from Mike Meissner.
4710 PSIM is a very elaborate model of the PowerPC, including not only
4711 basic instruction set execution, but also details of execution unit
4712 performance and I/O hardware. See sim/ppc/README for more details.
4716 GDB now works with Solaris 2.5.
4718 * Windows 95/NT native
4720 GDB will now work as a native debugger on Windows 95 and Windows NT.
4721 To build it from source, you must use the "gnu-win32" environment,
4722 which uses a DLL to emulate enough of Unix to run the GNU tools.
4723 Further information, binaries, and sources are available at
4724 ftp.cygnus.com, under pub/gnu-win32.
4726 * dont-repeat command
4728 If a user-defined command includes the command `dont-repeat', then the
4729 command will not be repeated if the user just types return. This is
4730 useful if the command is time-consuming to run, so that accidental
4731 extra keystrokes don't run the same command many times.
4733 * Send break instead of ^C
4735 The standard remote protocol now includes an option to send a break
4736 rather than a ^C to the target in order to interrupt it. By default,
4737 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4739 * Remote protocol timeout
4741 The standard remote protocol includes a new variable `remotetimeout'
4742 that allows you to set the number of seconds before GDB gives up trying
4743 to read from the target. The default value is 2.
4745 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4747 By default GDB will automatically keep track of objects as they are
4748 loaded and unloaded by the dynamic linker. By using the command `set
4749 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4750 when shared library events occur, thus allowing you to set breakpoints
4751 in shared libraries which are explicitly loaded by the inferior.
4753 Note this feature does not work on hpux8. On hpux9 you must link
4754 /usr/lib/end.o into your program. This feature should work
4755 automatically on hpux10.
4757 * Irix 5.x hardware watchpoint support
4759 Irix 5 configurations now support the use of hardware watchpoints.
4761 * Mips protocol "SYN garbage limit"
4763 When debugging a Mips target using the `target mips' protocol, you
4764 may set the number of characters that GDB will ignore by setting
4765 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4766 every character. The default value is 1050.
4768 * Recording and replaying remote debug sessions
4770 If you set `remotelogfile' to the name of a file, gdb will write to it
4771 a recording of a remote debug session. This recording may then be
4772 replayed back to gdb using "gdbreplay". See gdbserver/README for
4773 details. This is useful when you have a problem with GDB while doing
4774 remote debugging; you can make a recording of the session and send it
4775 to someone else, who can then recreate the problem.
4777 * Speedups for remote debugging
4779 GDB includes speedups for downloading and stepping MIPS systems using
4780 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4781 and more efficient S-record downloading.
4783 * Memory use reductions and statistics collection
4785 GDB now uses less memory and reports statistics about memory usage.
4786 Try the `maint print statistics' command, for example.
4788 *** Changes in GDB-4.15:
4790 * Psymtabs for XCOFF
4792 The symbol reader for AIX GDB now uses partial symbol tables. This
4793 can greatly improve startup time, especially for large executables.
4795 * Remote targets use caching
4797 Remote targets now use a data cache to speed up communication with the
4798 remote side. The data cache could lead to incorrect results because
4799 it doesn't know about volatile variables, thus making it impossible to
4800 debug targets which use memory mapped I/O devices. `set remotecache
4801 off' turns the the data cache off.
4803 * Remote targets may have threads
4805 The standard remote protocol now includes support for multiple threads
4806 in the target system, using new protocol commands 'H' and 'T'. See
4807 gdb/remote.c for details.
4811 If GDB is configured with `--enable-netrom', then it will include
4812 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4813 acts as though it is a bank of ROM on the target board, but you can
4814 write into it over the network. GDB's support consists only of
4815 support for fast loading into the emulated ROM; to debug, you must use
4816 another protocol, such as standard remote protocol. The usual
4817 sequence is something like
4819 target nrom <netrom-hostname>
4821 target remote <netrom-hostname>:1235
4825 GDB now includes support for the Apple Macintosh, as a host only. It
4826 may be run as either an MPW tool or as a standalone application, and
4827 it can debug through the serial port. All the usual GDB commands are
4828 available, but to the target command, you must supply "serial" as the
4829 device type instead of "/dev/ttyXX". See mpw-README in the main
4830 directory for more information on how to build. The MPW configuration
4831 scripts */mpw-config.in support only a few targets, and only the
4832 mips-idt-ecoff target has been tested.
4836 GDB configuration now uses autoconf. This is not user-visible,
4837 but does simplify configuration and building.
4841 GDB now supports hpux10.
4843 *** Changes in GDB-4.14:
4845 * New native configurations
4847 x86 FreeBSD i[345]86-*-freebsd
4848 x86 NetBSD i[345]86-*-netbsd
4849 NS32k NetBSD ns32k-*-netbsd
4850 Sparc NetBSD sparc-*-netbsd
4854 A29K VxWorks a29k-*-vxworks
4855 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4856 CPU32 EST-300 emulator m68*-*-est*
4857 PowerPC ELF powerpc-*-elf
4860 * Alpha OSF/1 support for procfs
4862 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4863 possible to attach to running processes. As the mounting of the /proc
4864 filesystem is optional on the Alpha, GDB automatically determines
4865 the availability of /proc during startup. This can lead to problems
4866 if /proc is unmounted after GDB has been started.
4868 * Arguments to user-defined commands
4870 User commands may accept up to 10 arguments separated by whitespace.
4871 Arguments are accessed within the user command via $arg0..$arg9. A
4874 print $arg0 + $arg1 + $arg2
4876 To execute the command use:
4879 Defines the command "adder" which prints the sum of its three arguments.
4880 Note the arguments are text substitutions, so they may reference variables,
4881 use complex expressions, or even perform inferior function calls.
4883 * New `if' and `while' commands
4885 This makes it possible to write more sophisticated user-defined
4886 commands. Both commands take a single argument, which is the
4887 expression to evaluate, and must be followed by the commands to
4888 execute, one per line, if the expression is nonzero, the list being
4889 terminated by the word `end'. The `if' command list may include an
4890 `else' word, which causes the following commands to be executed only
4891 if the expression is zero.
4893 * Fortran source language mode
4895 GDB now includes partial support for Fortran 77. It will recognize
4896 Fortran programs and can evaluate a subset of Fortran expressions, but
4897 variables and functions may not be handled correctly. GDB will work
4898 with G77, but does not yet know much about symbols emitted by other
4901 * Better HPUX support
4903 Most debugging facilities now work on dynamic executables for HPPAs
4904 running hpux9 or later. You can attach to running dynamically linked
4905 processes, but by default the dynamic libraries will be read-only, so
4906 for instance you won't be able to put breakpoints in them. To change
4907 that behavior do the following before running the program:
4913 This will cause the libraries to be mapped private and read-write.
4914 To revert to the normal behavior, do this:
4920 You cannot set breakpoints or examine data in the library until after
4921 the library is loaded if the function/data symbols do not have
4924 GDB can now also read debug symbols produced by the HP C compiler on
4925 HPPAs (sorry, no C++, Fortran or 68k support).
4927 * Target byte order now dynamically selectable
4929 You can choose which byte order to use with a target system, via the
4930 commands "set endian big" and "set endian little", and you can see the
4931 current setting by using "show endian". You can also give the command
4932 "set endian auto", in which case GDB will use the byte order
4933 associated with the executable. Currently, only embedded MIPS
4934 configurations support dynamic selection of target byte order.
4936 * New DOS host serial code
4938 This version uses DPMI interrupts to handle buffered I/O, so you
4939 no longer need to run asynctsr when debugging boards connected to
4942 *** Changes in GDB-4.13:
4944 * New "complete" command
4946 This lists all the possible completions for the rest of the line, if it
4947 were to be given as a command itself. This is intended for use by emacs.
4949 * Trailing space optional in prompt
4951 "set prompt" no longer adds a space for you after the prompt you set. This
4952 allows you to set a prompt which ends in a space or one that does not.
4954 * Breakpoint hit counts
4956 "info break" now displays a count of the number of times the breakpoint
4957 has been hit. This is especially useful in conjunction with "ignore"; you
4958 can ignore a large number of breakpoint hits, look at the breakpoint info
4959 to see how many times the breakpoint was hit, then run again, ignoring one
4960 less than that number, and this will get you quickly to the last hit of
4963 * Ability to stop printing at NULL character
4965 "set print null-stop" will cause GDB to stop printing the characters of
4966 an array when the first NULL is encountered. This is useful when large
4967 arrays actually contain only short strings.
4969 * Shared library breakpoints
4971 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4972 breakpoints in shared libraries before the executable is run.
4974 * Hardware watchpoints
4976 There is a new hardware breakpoint for the watch command for sparclite
4977 targets. See gdb/sparclite/hw_breakpoint.note.
4979 Hardware watchpoints are also now supported under GNU/Linux.
4983 Annotations have been added. These are for use with graphical interfaces,
4984 and are still experimental. Currently only gdba.el uses these.
4986 * Improved Irix 5 support
4988 GDB now works properly with Irix 5.2.
4990 * Improved HPPA support
4992 GDB now works properly with the latest GCC and GAS.
4994 * New native configurations
4996 Sequent PTX4 i[34]86-sequent-ptx4
4997 HPPA running OSF/1 hppa*-*-osf*
4998 Atari TT running SVR4 m68*-*-sysv4*
4999 RS/6000 LynxOS rs6000-*-lynxos*
5003 OS/9000 i[34]86-*-os9k
5004 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5007 * Hitachi SH7000 and E7000-PC ICE support
5009 There is now support for communicating with the Hitachi E7000-PC ICE.
5010 This is available automatically when GDB is configured for the SH.
5014 As usual, a variety of small fixes and improvements, both generic
5015 and configuration-specific. See the ChangeLog for more detail.
5017 *** Changes in GDB-4.12:
5019 * Irix 5 is now supported
5023 GDB-4.12 on the HPPA has a number of changes which make it unable
5024 to debug the output from the currently released versions of GCC and
5025 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5026 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5027 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5030 *** Changes in GDB-4.11:
5032 * User visible changes:
5036 The "set remotedebug" option is now consistent between the mips remote
5037 target, remote targets using the gdb-specific protocol, UDI (AMD's
5038 debug protocol for the 29k) and the 88k bug monitor. It is now an
5039 integer specifying a debug level (normally 0 or 1, but 2 means more
5040 debugging info for the mips target).
5042 * DEC Alpha native support
5044 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5045 debug info, but GDB works fairly well with the DEC compiler and should
5046 work with a future GCC release. See the README file for a few
5047 Alpha-specific notes.
5049 * Preliminary thread implementation
5051 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5053 * LynxOS native and target support for 386
5055 This release has been hosted on LynxOS 2.2, and also can be configured
5056 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5059 * Improvements in C++ mangling/demangling.
5061 This release has much better g++ debugging, specifically in name
5062 mangling/demangling, virtual function calls, print virtual table,
5063 call methods, ...etc.
5065 *** Changes in GDB-4.10:
5067 * User visible changes:
5069 Remote debugging using the GDB-specific (`target remote') protocol now
5070 supports the `load' command. This is only useful if you have some
5071 other way of getting the stub to the target system, and you can put it
5072 somewhere in memory where it won't get clobbered by the download.
5074 Filename completion now works.
5076 When run under emacs mode, the "info line" command now causes the
5077 arrow to point to the line specified. Also, "info line" prints
5078 addresses in symbolic form (as well as hex).
5080 All vxworks based targets now support a user settable option, called
5081 vxworks-timeout. This option represents the number of seconds gdb
5082 should wait for responses to rpc's. You might want to use this if
5083 your vxworks target is, perhaps, a slow software simulator or happens
5084 to be on the far side of a thin network line.
5088 This release contains support for using a DEC alpha as a GDB host for
5089 cross debugging. Native alpha debugging is not supported yet.
5092 *** Changes in GDB-4.9:
5096 This is the first GDB release which is accompanied by a matching testsuite.
5097 The testsuite requires installation of dejagnu, which should be available
5098 via ftp from most sites that carry GNU software.
5102 'Cfront' style demangling has had its name changed to 'ARM' style, to
5103 emphasize that it was written from the specifications in the C++ Annotated
5104 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5105 disclaimers, it still generated too much confusion with users attempting to
5106 use gdb with AT&T cfront.
5110 GDB now uses a standard remote interface to a simulator library.
5111 So far, the library contains simulators for the Zilog Z8001/2, the
5112 Hitachi H8/300, H8/500 and Super-H.
5114 * New targets supported
5116 H8/300 simulator h8300-hitachi-hms or h8300hms
5117 H8/500 simulator h8500-hitachi-hms or h8500hms
5118 SH simulator sh-hitachi-hms or sh
5119 Z8000 simulator z8k-zilog-none or z8ksim
5120 IDT MIPS board over serial line mips-idt-ecoff
5122 Cross-debugging to GO32 targets is supported. It requires a custom
5123 version of the i386-stub.c module which is integrated with the
5124 GO32 memory extender.
5126 * New remote protocols
5128 MIPS remote debugging protocol.
5130 * New source languages supported
5132 This version includes preliminary support for Chill, a Pascal like language
5133 used by telecommunications companies. Chill support is also being integrated
5134 into the GNU compiler, but we don't know when it will be publically available.
5137 *** Changes in GDB-4.8:
5139 * HP Precision Architecture supported
5141 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5142 version of this support was available as a set of patches from the
5143 University of Utah. GDB does not support debugging of programs
5144 compiled with the HP compiler, because HP will not document their file
5145 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5146 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5148 Many problems in the preliminary version have been fixed.
5150 * Faster and better demangling
5152 We have improved template demangling and fixed numerous bugs in the GNU style
5153 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5154 character types (wchar_t) are now supported. Demangling of each symbol is now
5155 only done once, and is cached when the symbol table for a file is read in.
5156 This results in a small increase in memory usage for C programs, a moderate
5157 increase in memory usage for C++ programs, and a fantastic speedup in
5160 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5161 from the specifications in the Annotated Reference Manual, which AT&T's
5162 compiler does not actually implement.
5164 * G++ multiple inheritance compiler problem
5166 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5167 inheritance lattices was reworked to properly discover ambiguities. We
5168 recently found an example which causes this new algorithm to fail in a
5169 very subtle way, producing bad debug information for those classes.
5170 The file 'gcc.patch' (in this directory) can be applied to gcc to
5171 circumvent the problem. A future GCC release will contain a complete
5174 The previous G++ debug info problem (mentioned below for the gdb-4.7
5175 release) is fixed in gcc version 2.3.2.
5177 * Improved configure script
5179 The `configure' script will now attempt to guess your system type if
5180 you don't supply a host system type. The old scheme of supplying a
5181 host system triplet is preferable over using this. All the magic is
5182 done in the new `config.guess' script. Examine it for details.
5184 We have also brought our configure script much more in line with the FSF's
5185 version. It now supports the --with-xxx options. In particular,
5186 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5187 The resulting GDB will not be able to read arbitrary object file formats --
5188 only the format ``expected'' to be used on the configured target system.
5189 We hope to make this the default in a future release.
5191 * Documentation improvements
5193 There's new internal documentation on how to modify GDB, and how to
5194 produce clean changes to the code. We implore people to read it
5195 before submitting changes.
5197 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5198 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5199 `info' files are also provided. To build `info' files from scratch,
5200 you will need the latest `makeinfo' release, which will be available in
5201 a future texinfo-X.Y release.
5203 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5204 We're not sure exactly which versions have this problem, but it has
5205 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5206 or better. If that isn't possible, there is a patch in
5207 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5208 around this problem.
5212 GDB now supports array constants that can be used in expressions typed in by
5213 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5214 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5217 The new directory `gdb/sparclite' contains a program that demonstrates
5218 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5220 * New native hosts supported
5222 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5223 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5225 * New targets supported
5227 AMD 29k family via UDI a29k-amd-udi or udi29k
5229 * New file formats supported
5231 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5232 HPUX core files, and SCO 3.2v2 core files.
5236 Attaching to processes now works again; thanks for the many bug reports.
5238 We have also stomped on a bunch of core dumps caused by
5239 printf_filtered("%s") problems.
5241 We eliminated a copyright problem on the rpc and ptrace header files
5242 for VxWorks, which was discovered at the last minute during the 4.7
5243 release. You should now be able to build a VxWorks GDB.
5245 You can now interrupt gdb while an attached process is running. This
5246 will cause the attached process to stop, and give control back to GDB.
5248 We fixed problems caused by using too many file descriptors
5249 for reading symbols from object files and libraries. This was
5250 especially a problem for programs that used many (~100) shared
5253 The `step' command now only enters a subroutine if there is line number
5254 information for the subroutine. Otherwise it acts like the `next'
5255 command. Previously, `step' would enter subroutines if there was
5256 any debugging information about the routine. This avoids problems
5257 when using `cc -g1' on MIPS machines.
5259 * Internal improvements
5261 GDB's internal interfaces have been improved to make it easier to support
5262 debugging of multiple languages in the future.
5264 GDB now uses a common structure for symbol information internally.
5265 Minimal symbols (derived from linkage symbols in object files), partial
5266 symbols (from a quick scan of debug information), and full symbols
5267 contain a common subset of information, making it easier to write
5268 shared code that handles any of them.
5270 * New command line options
5272 We now accept --silent as an alias for --quiet.
5276 The memory-mapped-malloc library is now licensed under the GNU Library
5277 General Public License.
5279 *** Changes in GDB-4.7:
5281 * Host/native/target split
5283 GDB has had some major internal surgery to untangle the support for
5284 hosts and remote targets. Now, when you configure GDB for a remote
5285 target, it will no longer load in all of the support for debugging
5286 local programs on the host. When fully completed and tested, this will
5287 ensure that arbitrary host/target combinations are possible.
5289 The primary conceptual shift is to separate the non-portable code in
5290 GDB into three categories. Host specific code is required any time GDB
5291 is compiled on that host, regardless of the target. Target specific
5292 code relates to the peculiarities of the target, but can be compiled on
5293 any host. Native specific code is everything else: it can only be
5294 built when the host and target are the same system. Child process
5295 handling and core file support are two common `native' examples.
5297 GDB's use of /proc for controlling Unix child processes is now cleaner.
5298 It has been split out into a single module under the `target_ops' vector,
5299 plus two native-dependent functions for each system that uses /proc.
5301 * New hosts supported
5303 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5304 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5305 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5307 * New targets supported
5309 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5310 68030 and CPU32 m68030-*-*, m68332-*-*
5312 * New native hosts supported
5314 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5315 (386bsd is not well tested yet)
5316 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5318 * New file formats supported
5320 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5321 supports reading of `a.out.adobe' object files, which are an a.out
5322 format extended with minimal information about multiple sections.
5326 `show copying' is the same as the old `info copying'.
5327 `show warranty' is the same as `info warrantee'.
5328 These were renamed for consistency. The old commands continue to work.
5330 `info handle' is a new alias for `info signals'.
5332 You can now define pre-command hooks, which attach arbitrary command
5333 scripts to any command. The commands in the hook will be executed
5334 prior to the user's command. You can also create a hook which will be
5335 executed whenever the program stops. See gdb.texinfo.
5339 We now deal with Cfront style name mangling, and can even extract type
5340 info from mangled symbols. GDB can automatically figure out which
5341 symbol mangling style your C++ compiler uses.
5343 Calling of methods and virtual functions has been improved as well.
5347 The crash that occured when debugging Sun Ansi-C compiled binaries is
5348 fixed. This was due to mishandling of the extra N_SO stabs output
5351 We also finally got Ultrix 4.2 running in house, and fixed core file
5352 support, with help from a dozen people on the net.
5354 John M. Farrell discovered that the reason that single-stepping was so
5355 slow on all of the Mips based platforms (primarily SGI and DEC) was
5356 that we were trying to demangle and lookup a symbol used for internal
5357 purposes on every instruction that was being stepped through. Changing
5358 the name of that symbol so that it couldn't be mistaken for a C++
5359 mangled symbol sped things up a great deal.
5361 Rich Pixley sped up symbol lookups in general by getting much smarter
5362 about when C++ symbol mangling is necessary. This should make symbol
5363 completion (TAB on the command line) much faster. It's not as fast as
5364 we'd like, but it's significantly faster than gdb-4.6.
5368 A new user controllable variable 'call_scratch_address' can
5369 specify the location of a scratch area to be used when GDB
5370 calls a function in the target. This is necessary because the
5371 usual method of putting the scratch area on the stack does not work
5372 in systems that have separate instruction and data spaces.
5374 We integrated changes to support the 29k UDI (Universal Debugger
5375 Interface), but discovered at the last minute that we didn't have all
5376 of the appropriate copyright paperwork. We are working with AMD to
5377 resolve this, and hope to have it available soon.
5381 We have sped up the remote serial line protocol, especially for targets
5382 with lots of registers. It now supports a new `expedited status' ('T')
5383 message which can be used in place of the existing 'S' status message.
5384 This allows the remote stub to send only the registers that GDB
5385 needs to make a quick decision about single-stepping or conditional
5386 breakpoints, eliminating the need to fetch the entire register set for
5387 each instruction being stepped through.
5389 The GDB remote serial protocol now implements a write-through cache for
5390 registers, only re-reading the registers if the target has run.
5392 There is also a new remote serial stub for SPARC processors. You can
5393 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5394 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5395 processor with a serial port.
5399 Configure.in files have become much easier to read and modify. A new
5400 `table driven' format makes it more obvious what configurations are
5401 supported, and what files each one uses.
5405 There is a new opcodes library which will eventually contain all of the
5406 disassembly routines and opcode tables. At present, it only contains
5407 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5408 disassembler (binutils/objdump) to share these routines.
5410 The libiberty library is now copylefted under the GNU Library General
5411 Public License. This allows more liberal use, and was done so libg++
5412 can use it. This makes no difference to GDB, since the Library License
5413 grants all the rights from the General Public License.
5417 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5418 reference to the stabs symbol info used by the debugger. It is (as far
5419 as we know) the only published document on this fascinating topic. We
5420 encourage you to read it, compare it to the stabs information on your
5421 system, and send improvements on the document in general (to
5422 bug-gdb@prep.ai.mit.edu).
5424 And, of course, many bugs have been fixed.
5427 *** Changes in GDB-4.6:
5429 * Better support for C++ function names
5431 GDB now accepts as input the "demangled form" of C++ overloaded function
5432 names and member function names, and can do command completion on such names
5433 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5434 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5435 Make use of command completion, it is your friend.
5437 GDB also now accepts a variety of C++ mangled symbol formats. They are
5438 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5439 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5440 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5441 for the list of formats.
5443 * G++ symbol mangling problem
5445 Recent versions of gcc have a bug in how they emit debugging information for
5446 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5447 directory) can be applied to gcc to fix the problem. Alternatively, if you
5448 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5449 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5450 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5453 * New 'maintenance' command
5455 All of the commands related to hacking GDB internals have been moved out of
5456 the main command set, and now live behind the 'maintenance' command. This
5457 can also be abbreviated as 'mt'. The following changes were made:
5459 dump-me -> maintenance dump-me
5460 info all-breakpoints -> maintenance info breakpoints
5461 printmsyms -> maintenance print msyms
5462 printobjfiles -> maintenance print objfiles
5463 printpsyms -> maintenance print psymbols
5464 printsyms -> maintenance print symbols
5466 The following commands are new:
5468 maintenance demangle Call internal GDB demangler routine to
5469 demangle a C++ link name and prints the result.
5470 maintenance print type Print a type chain for a given symbol
5472 * Change to .gdbinit file processing
5474 We now read the $HOME/.gdbinit file before processing the argv arguments
5475 (e.g. reading symbol files or core files). This allows global parameters to
5476 be set, which will apply during the symbol reading. The ./.gdbinit is still
5477 read after argv processing.
5479 * New hosts supported
5481 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5483 GNU/Linux support i386-unknown-linux or linux
5485 We are also including code to support the HP/PA running BSD and HPUX. This
5486 is almost guaranteed not to work, as we didn't have time to test or build it
5487 for this release. We are including it so that the more adventurous (or
5488 masochistic) of you can play with it. We also had major problems with the
5489 fact that the compiler that we got from HP doesn't support the -g option.
5492 * New targets supported
5494 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5496 * More smarts about finding #include files
5498 GDB now remembers the compilation directory for all include files, and for
5499 all files from which C is generated (like yacc and lex sources). This
5500 greatly improves GDB's ability to find yacc/lex sources, and include files,
5501 especially if you are debugging your program from a directory different from
5502 the one that contains your sources.
5504 We also fixed a bug which caused difficulty with listing and setting
5505 breakpoints in include files which contain C code. (In the past, you had to
5506 try twice in order to list an include file that you hadn't looked at before.)
5508 * Interesting infernals change
5510 GDB now deals with arbitrary numbers of sections, where the symbols for each
5511 section must be relocated relative to that section's landing place in the
5512 target's address space. This work was needed to support ELF with embedded
5513 stabs used by Solaris-2.0.
5515 * Bug fixes (of course!)
5517 There have been loads of fixes for the following things:
5518 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5519 i960, stabs, DOS(GO32), procfs, etc...
5521 See the ChangeLog for details.
5523 *** Changes in GDB-4.5:
5525 * New machines supported (host and target)
5527 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5529 SGI Irix-4.x mips-sgi-irix4 or iris4
5531 * New malloc package
5533 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5534 Mmalloc is capable of handling mutiple heaps of memory. It is also
5535 capable of saving a heap to a file, and then mapping it back in later.
5536 This can be used to greatly speedup the startup of GDB by using a
5537 pre-parsed symbol table which lives in a mmalloc managed heap. For
5538 more details, please read mmalloc/mmalloc.texi.
5542 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5543 'help info proc' for details.
5545 * MIPS ecoff symbol table format
5547 The code that reads MIPS symbol table format is now supported on all hosts.
5548 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5551 * File name changes for MS-DOS
5553 Many files in the config directories have been renamed to make it easier to
5554 support GDB on MS-DOSe systems (which have very restrictive file name
5555 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5556 environment) is close to working but has some remaining problems. Note
5557 that debugging of DOS programs is not supported, due to limitations
5558 in the ``operating system'', but it can be used to host cross-debugging.
5560 * Cross byte order fixes
5562 Many fixes have been made to support cross debugging of Sparc and MIPS
5563 targets from hosts whose byte order differs.
5565 * New -mapped and -readnow options
5567 If memory-mapped files are available on your system through the 'mmap'
5568 system call, you can use the -mapped option on the `file' or
5569 `symbol-file' commands to cause GDB to write the symbols from your
5570 program into a reusable file. If the program you are debugging is
5571 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5572 Future GDB debugging sessions will notice the presence of this file,
5573 and will quickly map in symbol information from it, rather than reading
5574 the symbol table from the executable program. Using the '-mapped'
5575 option in a GDB `file' or `symbol-file' command has the same effect as
5576 starting GDB with the '-mapped' command-line option.
5578 You can cause GDB to read the entire symbol table immediately by using
5579 the '-readnow' option with any of the commands that load symbol table
5580 information (or on the GDB command line). This makes the command
5581 slower, but makes future operations faster.
5583 The -mapped and -readnow options are typically combined in order to
5584 build a `fred.syms' file that contains complete symbol information.
5585 A simple GDB invocation to do nothing but build a `.syms' file for future
5588 gdb -batch -nx -mapped -readnow programname
5590 The `.syms' file is specific to the host machine on which GDB is run.
5591 It holds an exact image of GDB's internal symbol table. It cannot be
5592 shared across multiple host platforms.
5594 * longjmp() handling
5596 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5597 siglongjmp() without losing control. This feature has not yet been ported to
5598 all systems. It currently works on many 386 platforms, all MIPS-based
5599 platforms (SGI, DECstation, etc), and Sun3/4.
5603 Preliminary work has been put in to support the new Solaris OS from Sun. At
5604 this time, it can control and debug processes, but it is not capable of
5609 As always, many many bug fixes. The major areas were with g++, and mipsread.
5610 People using the MIPS-based platforms should experience fewer mysterious
5611 crashes and trashed symbol tables.
5613 *** Changes in GDB-4.4:
5615 * New machines supported (host and target)
5617 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5619 BSD Reno on Vax vax-dec-bsd
5620 Ultrix on Vax vax-dec-ultrix
5622 * New machines supported (target)
5624 AMD 29000 embedded, using EBMON a29k-none-none
5628 GDB continues to improve its handling of C++. `References' work better.
5629 The demangler has also been improved, and now deals with symbols mangled as
5630 per the Annotated C++ Reference Guide.
5632 GDB also now handles `stabs' symbol information embedded in MIPS
5633 `ecoff' symbol tables. Since the ecoff format was not easily
5634 extensible to handle new languages such as C++, this appeared to be a
5635 good way to put C++ debugging info into MIPS binaries. This option
5636 will be supported in the GNU C compiler, version 2, when it is
5639 * New features for SVR4
5641 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5642 shared libraries. Debugging dynamically linked programs should present
5643 only minor differences from debugging statically linked programs.
5645 The `info proc' command will print out information about any process
5646 on an SVR4 system (including the one you are debugging). At the moment,
5647 it prints the address mappings of the process.
5649 If you bring up GDB on another SVR4 system, please send mail to
5650 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5652 * Better dynamic linking support in SunOS
5654 Reading symbols from shared libraries which contain debugging symbols
5655 now works properly. However, there remain issues such as automatic
5656 skipping of `transfer vector' code during function calls, which
5657 make it harder to debug code in a shared library, than to debug the
5658 same code linked statically.
5662 GDB is now using the latest `getopt' routines from the FSF. This
5663 version accepts the -- prefix for options with long names. GDB will
5664 continue to accept the old forms (-option and +option) as well.
5665 Various single letter abbreviations for options have been explicity
5666 added to the option table so that they won't get overshadowed in the
5667 future by other options that begin with the same letter.
5671 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5672 Many assorted bugs have been handled. Many more remain to be handled.
5673 See the various ChangeLog files (primarily in gdb and bfd) for details.
5676 *** Changes in GDB-4.3:
5678 * New machines supported (host and target)
5680 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5681 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5682 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5684 * Almost SCO Unix support
5686 We had hoped to support:
5687 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5688 (except for core file support), but we discovered very late in the release
5689 that it has problems with process groups that render gdb unusable. Sorry
5690 about that. I encourage people to fix it and post the fixes.
5692 * Preliminary ELF and DWARF support
5694 GDB can read ELF object files on System V Release 4, and can handle
5695 debugging records for C, in DWARF format, in ELF files. This support
5696 is preliminary. If you bring up GDB on another SVR4 system, please
5697 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5702 GDB now uses the latest `readline' library. One user-visible change
5703 is that two tabs will list possible command completions, which previously
5704 required typing M-? (meta-question mark, or ESC ?).
5708 The `stepi' bug that many of you noticed has been squashed.
5709 Many bugs in C++ have been handled. Many more remain to be handled.
5710 See the various ChangeLog files (primarily in gdb and bfd) for details.
5712 * State of the MIPS world (in case you wondered):
5714 GDB can understand the symbol tables emitted by the compilers
5715 supplied by most vendors of MIPS-based machines, including DEC. These
5716 symbol tables are in a format that essentially nobody else uses.
5718 Some versions of gcc come with an assembler post-processor called
5719 mips-tfile. This program is required if you want to do source-level
5720 debugging of gcc-compiled programs. I believe FSF does not ship
5721 mips-tfile with gcc version 1, but it will eventually come with gcc
5724 Debugging of g++ output remains a problem. g++ version 1.xx does not
5725 really support it at all. (If you're lucky, you should be able to get
5726 line numbers and stack traces to work, but no parameters or local
5727 variables.) With some work it should be possible to improve the
5730 When gcc version 2 is released, you will have somewhat better luck.
5731 However, even then you will get confusing results for inheritance and
5734 We will eventually provide full debugging of g++ output on
5735 DECstations. This will probably involve some kind of stabs-in-ecoff
5736 encapulation, but the details have not been worked out yet.
5739 *** Changes in GDB-4.2:
5741 * Improved configuration
5743 Only one copy of `configure' exists now, and it is not self-modifying.
5744 Porting BFD is simpler.
5748 The `step' and `next' commands now only stop at the first instruction
5749 of a source line. This prevents the multiple stops that used to occur
5750 in switch statements, for-loops, etc. `Step' continues to stop if a
5751 function that has debugging information is called within the line.
5755 Lots of small bugs fixed. More remain.
5757 * New host supported (not target)
5759 Intel 386 PC clone running Mach i386-none-mach
5762 *** Changes in GDB-4.1:
5764 * Multiple source language support
5766 GDB now has internal scaffolding to handle several source languages.
5767 It determines the type of each source file from its filename extension,
5768 and will switch expression parsing and number formatting to match the
5769 language of the function in the currently selected stack frame.
5770 You can also specifically set the language to be used, with
5771 `set language c' or `set language modula-2'.
5775 GDB now has preliminary support for the GNU Modula-2 compiler,
5776 currently under development at the State University of New York at
5777 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5778 continue through the fall of 1991 and into 1992.
5780 Other Modula-2 compilers are currently not supported, and attempting to
5781 debug programs compiled with them will likely result in an error as the
5782 symbol table is read. Feel free to work on it, though!
5784 There are hooks in GDB for strict type checking and range checking,
5785 in the `Modula-2 philosophy', but they do not currently work.
5789 GDB can now write to executable and core files (e.g. patch
5790 a variable's value). You must turn this switch on, specify
5791 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5792 by assigning a new value to a variable. Modifications take
5795 * Automatic SunOS shared library reading
5797 When you run your program, GDB automatically determines where its
5798 shared libraries (if any) have been loaded, and reads their symbols.
5799 The `share' command is no longer needed. This also works when
5800 examining core files.
5804 You can specify the number of lines that the `list' command shows.
5807 * New machines supported (host and target)
5809 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5810 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5811 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5813 * New hosts supported (not targets)
5815 IBM RT/PC: romp-ibm-aix or rtpc
5817 * New targets supported (not hosts)
5819 AMD 29000 embedded with COFF a29k-none-coff
5820 AMD 29000 embedded with a.out a29k-none-aout
5821 Ultracomputer remote kernel debug a29k-nyu-kern
5823 * New remote interfaces
5829 *** Changes in GDB-4.0:
5833 Wide output is wrapped at good places to make the output more readable.
5835 Gdb now supports cross-debugging from a host machine of one type to a
5836 target machine of another type. Communication with the target system
5837 is over serial lines. The ``target'' command handles connecting to the
5838 remote system; the ``load'' command will download a program into the
5839 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5840 also supports debugging of realtime processes running under VxWorks,
5841 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5842 stub on the target system.
5844 New CPUs supported include the AMD 29000 and Intel 960.
5846 GDB now reads object files and symbol tables via a ``binary file''
5847 library, which allows a single copy of GDB to debug programs of multiple
5848 object file types such as a.out and coff.
5850 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5851 refcard.dvi and refcard.ps are available to format it).
5854 * Control-Variable user interface simplified
5856 All variables that control the operation of the debugger can be set
5857 by the ``set'' command, and displayed by the ``show'' command.
5859 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5860 ``Show prompt'' produces the response:
5861 Gdb's prompt is new-gdb=>.
5863 What follows are the NEW set commands. The command ``help set'' will
5864 print a complete list of old and new set commands. ``help set FOO''
5865 will give a longer description of the variable FOO. ``show'' will show
5866 all of the variable descriptions and their current settings.
5868 confirm on/off: Enables warning questions for operations that are
5869 hard to recover from, e.g. rerunning the program while
5870 it is already running. Default is ON.
5872 editing on/off: Enables EMACS style command line editing
5873 of input. Previous lines can be recalled with
5874 control-P, the current line can be edited with control-B,
5875 you can search for commands with control-R, etc.
5878 history filename NAME: NAME is where the gdb command history
5879 will be stored. The default is .gdb_history,
5880 or the value of the environment variable
5883 history size N: The size, in commands, of the command history. The
5884 default is 256, or the value of the environment variable
5887 history save on/off: If this value is set to ON, the history file will
5888 be saved after exiting gdb. If set to OFF, the
5889 file will not be saved. The default is OFF.
5891 history expansion on/off: If this value is set to ON, then csh-like
5892 history expansion will be performed on
5893 command line input. The default is OFF.
5895 radix N: Sets the default radix for input and output. It can be set
5896 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5897 in the current radix, so "set radix 10" is always a no-op.
5899 height N: This integer value is the number of lines on a page. Default
5900 is 24, the current `stty rows'' setting, or the ``li#''
5901 setting from the termcap entry matching the environment
5904 width N: This integer value is the number of characters on a line.
5905 Default is 80, the current `stty cols'' setting, or the ``co#''
5906 setting from the termcap entry matching the environment
5909 Note: ``set screensize'' is obsolete. Use ``set height'' and
5910 ``set width'' instead.
5912 print address on/off: Print memory addresses in various command displays,
5913 such as stack traces and structure values. Gdb looks
5914 more ``symbolic'' if you turn this off; it looks more
5915 ``machine level'' with it on. Default is ON.
5917 print array on/off: Prettyprint arrays. New convenient format! Default
5920 print demangle on/off: Print C++ symbols in "source" form if on,
5923 print asm-demangle on/off: Same, for assembler level printouts
5926 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5929 * Support for Epoch Environment.
5931 The epoch environment is a version of Emacs v18 with windowing. One
5932 new command, ``inspect'', is identical to ``print'', except that if you
5933 are running in the epoch environment, the value is printed in its own
5937 * Support for Shared Libraries
5939 GDB can now debug programs and core files that use SunOS shared libraries.
5940 Symbols from a shared library cannot be referenced
5941 before the shared library has been linked with the program (this
5942 happens after you type ``run'' and before the function main() is entered).
5943 At any time after this linking (including when examining core files
5944 from dynamically linked programs), gdb reads the symbols from each
5945 shared library when you type the ``sharedlibrary'' command.
5946 It can be abbreviated ``share''.
5948 sharedlibrary REGEXP: Load shared object library symbols for files
5949 matching a unix regular expression. No argument
5950 indicates to load symbols for all shared libraries.
5952 info sharedlibrary: Status of loaded shared libraries.
5957 A watchpoint stops execution of a program whenever the value of an
5958 expression changes. Checking for this slows down execution
5959 tremendously whenever you are in the scope of the expression, but is
5960 quite useful for catching tough ``bit-spreader'' or pointer misuse
5961 problems. Some machines such as the 386 have hardware for doing this
5962 more quickly, and future versions of gdb will use this hardware.
5964 watch EXP: Set a watchpoint (breakpoint) for an expression.
5966 info watchpoints: Information about your watchpoints.
5968 delete N: Deletes watchpoint number N (same as breakpoints).
5969 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5970 enable N: Re-enables watchpoint number N (same as breakpoints).
5973 * C++ multiple inheritance
5975 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5978 * C++ exception handling
5980 Gdb now supports limited C++ exception handling. Besides the existing
5981 ability to breakpoint on an exception handler, gdb can breakpoint on
5982 the raising of an exception (before the stack is peeled back to the
5985 catch FOO: If there is a FOO exception handler in the dynamic scope,
5986 set a breakpoint to catch exceptions which may be raised there.
5987 Multiple exceptions (``catch foo bar baz'') may be caught.
5989 info catch: Lists all exceptions which may be caught in the
5990 current stack frame.
5993 * Minor command changes
5995 The command ``call func (arg, arg, ...)'' now acts like the print
5996 command, except it does not print or save a value if the function's result
5997 is void. This is similar to dbx usage.
5999 The ``up'' and ``down'' commands now always print the frame they end up
6000 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6001 frames without printing.
6003 * New directory command
6005 'dir' now adds directories to the FRONT of the source search path.
6006 The path starts off empty. Source files that contain debug information
6007 about the directory in which they were compiled can be found even
6008 with an empty path; Sun CC and GCC include this information. If GDB can't
6009 find your source file in the current directory, type "dir .".
6011 * Configuring GDB for compilation
6013 For normal use, type ``./configure host''. See README or gdb.texinfo
6016 GDB now handles cross debugging. If you are remotely debugging between
6017 two different machines, type ``./configure host -target=targ''.
6018 Host is the machine where GDB will run; targ is the machine
6019 where the program that you are debugging will run.