1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.9
6 * GDB now honors the content of the file /proc/PID/coredump_filter
7 (PID is the process ID) on GNU/Linux systems. This file can be used
8 to specify the types of memory mappings that will be included in a
9 corefile. For more information, please refer to the manual page of
10 "core(5)". GDB also has a new command: "set use-coredump-filter
11 on|off". It allows to set whether GDB will read the content of the
12 /proc/PID/coredump_filter file when generating a corefile.
14 * The "info os" command on GNU/Linux can now display information on
16 "info os cpus" Listing of all cpus/cores on the system
18 * GDB has two new commands: "set serial parity odd|even|none" and
19 "show serial parity". These allows to set or show parity for the
22 * The "info source" command now displays the producer string if it was
23 present in the debug info. This typically includes the compiler version
24 and may include things like its command line arguments.
26 * The "info dll", an alias of the "info sharedlibrary" command,
27 is now available on all platforms.
29 * Directory names supplied to the "set sysroot" commands may be
30 prefixed with "target:" to tell GDB to access shared libraries from
31 the target system, be it local or remote. This replaces the prefix
32 "remote:". The default sysroot has been changed from "" to
33 "target:". "remote:" is automatically converted to "target:" for
34 backward compatibility.
36 * The system root specified by "set sysroot" will be prepended to the
37 filename of the main executable (if reported to GDB as absolute by
38 the operating system) when starting processes remotely, and when
39 attaching to already-running local or remote processes.
41 * GDB now supports automatic location and retrieval of executable
42 files from remote targets. Remote debugging can now be initiated
43 using only a "target remote" or "target extended-remote" command
44 (no "set sysroot" or "file" commands are required). See "New remote
47 * The "dump" command now supports verilog hex format.
49 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
53 ** gdb.Objfile objects have a new attribute "username",
54 which is the name of the objfile as specified by the user,
55 without, for example, resolving symlinks.
56 ** You can now write frame unwinders in Python.
57 ** gdb.Type objects have a new method "optimized_out",
58 returning optimized out gdb.Value instance of this type.
59 ** Xmethods can now specify a result type.
60 ** gdb.Value objects have new methods "reference_value" and
61 "const_value" which return a reference to the value and a
62 "const" version of the value respectively.
66 maint print symbol-cache
67 Print the contents of the symbol cache.
69 maint print symbol-cache-statistics
70 Print statistics of symbol cache usage.
72 maint flush-symbol-cache
73 Flush the contents of the symbol cache.
77 Start branch trace recording using Branch Trace Store (BTS) format.
83 Set the maximum number of candidates to be considered during
84 completion. The default value is 200. This limit allows GDB
85 to avoid generating large completion lists, the computation of
86 which can cause the debugger to become temporarily unresponsive.
88 maint set symbol-cache-size
89 maint show symbol-cache-size
90 Control the size of the symbol cache.
92 set|show record btrace bts buffer-size
93 Set and show the size of the ring buffer used for branch tracing in
95 The obtained size may differ from the requested size. Use "info
96 record" to see the obtained buffer size.
98 * The command 'thread apply all' can now support new option '-ascending'
99 to call its specified command for all threads in ascending order.
101 * Python/Guile scripting
103 ** GDB now supports auto-loading of Python/Guile scripts contained in the
104 special section named `.debug_gdb_scripts'.
108 qXfer:btrace-conf:read
109 Return the branch trace configuration for the current thread.
111 Qbtrace-conf:bts:size
112 Set the requested ring buffer size for branch tracing in BTS format.
115 Indicates a memory breakpoint instruction was executed, irrespective
116 of whether it was GDB that planted the breakpoint or the breakpoint
117 is hardcoded in the program. This is required for correct non-stop
121 Indicates the target stopped for a hardware breakpoint. This is
122 required for correct non-stop mode operation.
125 Return information about files on the remote system.
128 Return the full absolute name of the file that was executed to
129 create a process running on the remote system.
131 * The info record command now shows the recording format and the
132 branch tracing configuration for the current thread when using
133 the btrace record target.
134 For the BTS format, it shows the ring buffer size.
136 * GDB now has support for DTrace USDT (Userland Static Defined
137 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
139 * GDB now supports access to vector registers on S/390 GNU/Linux
142 * Removed command line options
144 -xdb HP-UX XDB compatibility mode.
146 * Removed targets and native configurations
148 HP/PA running HP-UX hppa*-*-hpux*
149 Itanium running HP-UX ia64-*-hpux*
151 *** Changes in GDB 7.9
153 * GDB now supports hardware watchpoints on x86 GNU Hurd.
157 ** You can now access frame registers from Python scripts.
158 ** New attribute 'producer' for gdb.Symtab objects.
159 ** gdb.Objfile objects have a new attribute "progspace",
160 which is the gdb.Progspace object of the containing program space.
161 ** gdb.Objfile objects have a new attribute "owner".
162 ** gdb.Objfile objects have a new attribute "build_id",
163 which is the build ID generated when the file was built.
164 ** gdb.Objfile objects have a new method "add_separate_debug_file".
165 ** A new event "gdb.clear_objfiles" has been added, triggered when
166 selecting a new file to debug.
167 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
168 ** New function gdb.lookup_objfile.
170 New events which are triggered when GDB modifies the state of the
173 ** gdb.events.inferior_call_pre: Function call is about to be made.
174 ** gdb.events.inferior_call_post: Function call has just been made.
175 ** gdb.events.memory_changed: A memory location has been altered.
176 ** gdb.events.register_changed: A register has been altered.
178 * New Python-based convenience functions:
180 ** $_caller_is(name [, number_of_frames])
181 ** $_caller_matches(regexp [, number_of_frames])
182 ** $_any_caller_is(name [, number_of_frames])
183 ** $_any_caller_matches(regexp [, number_of_frames])
185 * GDB now supports the compilation and injection of source code into
186 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
187 to compile the source code to object code, and if successful, inject
188 and execute that code within the current context of the inferior.
189 Currently the C language is supported. The commands used to
190 interface with this new feature are:
192 compile code [-raw|-r] [--] [source code]
193 compile file [-raw|-r] filename
197 demangle [-l language] [--] name
198 Demangle "name" in the specified language, or the current language
199 if elided. This command is renamed from the "maint demangle" command.
200 The latter is kept as a no-op to avoid "maint demangle" being interpreted
201 as "maint demangler-warning".
203 queue-signal signal-name-or-number
204 Queue a signal to be delivered to the thread when it is resumed.
206 add-auto-load-scripts-directory directory
207 Add entries to the list of directories from which to load auto-loaded
210 maint print user-registers
211 List all currently available "user" registers.
213 compile code [-r|-raw] [--] [source code]
214 Compile, inject, and execute in the inferior the executable object
215 code produced by compiling the provided source code.
217 compile file [-r|-raw] filename
218 Compile and inject into the inferior the executable object code
219 produced by compiling the source code stored in the filename
222 * On resume, GDB now always passes the signal the program had stopped
223 for to the thread the signal was sent to, even if the user changed
224 threads before resuming. Previously GDB would often (but not
225 always) deliver the signal to the thread that happens to be current
228 * Conversely, the "signal" command now consistently delivers the
229 requested signal to the current thread. GDB now asks for
230 confirmation if the program had stopped for a signal and the user
231 switched threads meanwhile.
233 * "breakpoint always-inserted" modes "off" and "auto" merged.
235 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
236 won't remove breakpoints from the target until all threads stop,
237 even in non-stop mode. The "auto" mode has been removed, and "off"
238 is now the default mode.
242 set debug symbol-lookup
243 show debug symbol-lookup
244 Control display of debugging info regarding symbol lookup.
248 ** The -list-thread-groups command outputs an exit-code field for
249 inferiors that have exited.
253 MIPS SDE mips*-sde*-elf*
257 Support for these obsolete configurations has been removed.
259 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
260 SGI Irix-5.x mips-*-irix5*
261 SGI Irix-6.x mips-*-irix6*
262 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
263 VAX running Ultrix vax-*-ultrix*
265 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
266 and "assf"), have been removed. Use the "sharedlibrary" command, or
267 its alias "share", instead.
269 *** Changes in GDB 7.8
271 * New command line options
274 This is an alias for the --data-directory option.
276 * GDB supports printing and modifying of variable length automatic arrays
277 as specified in ISO C99.
279 * The ARM simulator now supports instruction level tracing
280 with or without disassembly.
284 GDB now has support for scripting using Guile. Whether this is
285 available is determined at configure time.
286 Guile version 2.0 or greater is required.
287 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
289 * New commands (for set/show, see "New options" below)
293 Invoke CODE by passing it to the Guile interpreter.
297 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
299 info auto-load guile-scripts [regexp]
300 Print the list of automatically loaded Guile scripts.
302 * The source command is now capable of sourcing Guile scripts.
303 This feature is dependent on the debugger being built with Guile support.
307 set print symbol-loading (off|brief|full)
308 show print symbol-loading
309 Control whether to print informational messages when loading symbol
310 information for a file. The default is "full", but when debugging
311 programs with large numbers of shared libraries the amount of output
314 set guile print-stack (none|message|full)
315 show guile print-stack
316 Show a stack trace when an error is encountered in a Guile script.
318 set auto-load guile-scripts (on|off)
319 show auto-load guile-scripts
320 Control auto-loading of Guile script files.
322 maint ada set ignore-descriptive-types (on|off)
323 maint ada show ignore-descriptive-types
324 Control whether the debugger should ignore descriptive types in Ada
325 programs. The default is not to ignore the descriptive types. See
326 the user manual for more details on descriptive types and the intended
327 usage of this option.
329 set auto-connect-native-target
331 Control whether GDB is allowed to automatically connect to the
332 native target for the run, attach, etc. commands when not connected
333 to any target yet. See also "target native" below.
335 set record btrace replay-memory-access (read-only|read-write)
336 show record btrace replay-memory-access
337 Control what memory accesses are allowed during replay.
339 maint set target-async (on|off)
340 maint show target-async
341 This controls whether GDB targets operate in synchronous or
342 asynchronous mode. Normally the default is asynchronous, if it is
343 available; but this can be changed to more easily debug problems
344 occurring only in synchronous mode.
346 set mi-async (on|off)
348 Control whether MI asynchronous mode is preferred. This supersedes
349 "set target-async" of previous GDB versions.
351 * "set target-async" is deprecated as a CLI option and is now an alias
352 for "set mi-async" (only puts MI into async mode).
354 * Background execution commands (e.g., "c&", "s&", etc.) are now
355 possible ``out of the box'' if the target supports them. Previously
356 the user would need to explicitly enable the possibility with the
357 "set target-async on" command.
359 * New features in the GDB remote stub, GDBserver
361 ** New option --debug-format=option1[,option2,...] allows one to add
362 additional text to each output. At present only timestamps
363 are supported: --debug-format=timestamps.
364 Timestamps can also be turned on with the
365 "monitor set debug-format timestamps" command from GDB.
367 * The 'record instruction-history' command now starts counting instructions
368 at one. This also affects the instruction ranges reported by the
369 'record function-call-history' command when given the /i modifier.
371 * The command 'record function-call-history' supports a new modifier '/c' to
372 indent the function names based on their call stack depth.
373 The fields for the '/i' and '/l' modifier have been reordered.
374 The source line range is now prefixed with 'at'.
375 The instruction range is now prefixed with 'inst'.
376 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
377 "record instruction-history" and "list" commands.
379 * The ranges given as arguments to the 'record function-call-history' and
380 'record instruction-history' commands are now inclusive.
382 * The btrace record target now supports the 'record goto' command.
383 For locations inside the execution trace, the back trace is computed
384 based on the information stored in the execution trace.
386 * The btrace record target supports limited reverse execution and replay.
387 The target does not record data and therefore does not allow reading
390 * The "catch syscall" command now works on s390*-linux* targets.
392 * The "compare-sections" command is no longer specific to target
393 remote. It now works with all targets.
395 * All native targets are now consistently called "native".
396 Consequently, the "target child", "target GNU", "target djgpp",
397 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
398 commands have been replaced with "target native". The QNX/NTO port
399 leaves the "procfs" target in place and adds a "native" target for
400 consistency with other ports. The impact on users should be minimal
401 as these commands previously either throwed an error, or were
402 no-ops. The target's name is visible in the output of the following
403 commands: "help target", "info target", "info files", "maint print
406 * The "target native" command now connects to the native target. This
407 can be used to launch native programs even when "set
408 auto-connect-native-target" is set to off.
410 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
412 * Support for Intel(R) AVX-512 registers on GNU/Linux.
413 Support displaying and modifying Intel(R) AVX-512 registers
414 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
418 qXfer:btrace:read's annex
419 The qXfer:btrace:read packet supports a new annex 'delta' to read
420 branch trace incrementally.
424 ** Valid Python operations on gdb.Value objects representing
425 structs/classes invoke the corresponding overloaded operators if
427 ** New `Xmethods' feature in the Python API. Xmethods are
428 additional methods or replacements for existing methods of a C++
429 class. This feature is useful for those cases where a method
430 defined in C++ source code could be inlined or optimized out by
431 the compiler, making it unavailable to GDB.
434 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
436 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
437 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
438 its alias "share", instead.
440 * The commands "set remotebaud" and "show remotebaud" are no longer
441 supported. Use "set serial baud" and "show serial baud" (respectively)
446 ** A new option "-gdb-set mi-async" replaces "-gdb-set
447 target-async". The latter is left as a deprecated alias of the
448 former for backward compatibility. If the target supports it,
449 CLI background execution commands are now always possible by
450 default, independently of whether the frontend stated a
451 preference for asynchronous execution with "-gdb-set mi-async".
452 Previously "-gdb-set target-async off" affected both MI execution
453 commands and CLI execution commands.
455 *** Changes in GDB 7.7
457 * Improved support for process record-replay and reverse debugging on
458 arm*-linux* targets. Support for thumb32 and syscall instruction
459 recording has been added.
461 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
463 * GDB now supports Fission DWP file format version 2.
464 http://gcc.gnu.org/wiki/DebugFission
466 * New convenience function "$_isvoid", to check whether an expression
467 is void. A void expression is an expression where the type of the
468 result is "void". For example, some convenience variables may be
469 "void" when evaluated (e.g., "$_exitcode" before the execution of
470 the program being debugged; or an undefined convenience variable).
471 Another example, when calling a function whose return type is
474 * The "maintenance print objfiles" command now takes an optional regexp.
476 * The "catch syscall" command now works on arm*-linux* targets.
478 * GDB now consistently shows "<not saved>" when printing values of
479 registers the debug info indicates have not been saved in the frame
480 and there's nowhere to retrieve them from
481 (callee-saved/call-clobbered registers):
486 (gdb) info registers rax
489 Before, the former would print "<optimized out>", and the latter
490 "*value not available*".
492 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
497 ** Frame filters and frame decorators have been added.
498 ** Temporary breakpoints are now supported.
499 ** Line tables representation has been added.
500 ** New attribute 'parent_type' for gdb.Field objects.
501 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
502 ** New attribute 'name' for gdb.Type objects.
506 Nios II ELF nios2*-*-elf
507 Nios II GNU/Linux nios2*-*-linux
508 Texas Instruments MSP430 msp430*-*-elf
510 * Removed native configurations
512 Support for these a.out NetBSD and OpenBSD obsolete configurations has
513 been removed. ELF variants of these configurations are kept supported.
515 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
516 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
517 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
518 i[34567]86-*-openbsd3.[0-3]
519 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
520 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
521 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
525 Like "catch throw", but catches a re-thrown exception.
527 Renamed from old "maint check-symtabs".
529 Perform consistency checks on symtabs.
531 Expand symtabs matching an optional regexp.
534 Display the details of GDB configure-time options.
536 maint set|show per-command
537 maint set|show per-command space
538 maint set|show per-command time
539 maint set|show per-command symtab
540 Enable display of per-command gdb resource usage.
542 remove-symbol-file FILENAME
543 remove-symbol-file -a ADDRESS
544 Remove a symbol file added via add-symbol-file. The file to remove
545 can be identified by its filename or by an address that lies within
546 the boundaries of this symbol file in memory.
549 info exceptions REGEXP
550 Display the list of Ada exceptions defined in the program being
551 debugged. If provided, only the exceptions whose names match REGEXP
556 set debug symfile off|on
558 Control display of debugging info regarding reading symbol files and
559 symbol tables within those files
561 set print raw frame-arguments
562 show print raw frame-arguments
563 Set/show whether to print frame arguments in raw mode,
564 disregarding any defined pretty-printers.
566 set remote trace-status-packet
567 show remote trace-status-packet
568 Set/show the use of remote protocol qTStatus packet.
572 Control display of debugging messages related to Nios II targets.
576 Control whether target-assisted range stepping is enabled.
578 set startup-with-shell
579 show startup-with-shell
580 Specifies whether Unix child processes are started via a shell or
585 Use the target memory cache for accesses to the code segment. This
586 improves performance of remote debugging (particularly disassembly).
588 * You can now use a literal value 'unlimited' for options that
589 interpret 0 or -1 as meaning "unlimited". E.g., "set
590 trace-buffer-size unlimited" is now an alias for "set
591 trace-buffer-size -1" and "set height unlimited" is now an alias for
594 * The "set debug symtab-create" debugging option of GDB has been changed to
595 accept a verbosity level. 0 means "off", 1 provides basic debugging
596 output, and values of 2 or greater provides more verbose output.
598 * New command-line options
600 Display the details of GDB configure-time options.
602 * The command 'tsave' can now support new option '-ctf' to save trace
603 buffer in Common Trace Format.
605 * Newly installed $prefix/bin/gcore acts as a shell interface for the
608 * GDB now implements the the C++ 'typeid' operator.
610 * The new convenience variable $_exception holds the exception being
611 thrown or caught at an exception-related catchpoint.
613 * The exception-related catchpoints, like "catch throw", now accept a
614 regular expression which can be used to filter exceptions by type.
616 * The new convenience variable $_exitsignal is automatically set to
617 the terminating signal number when the program being debugged dies
618 due to an uncaught signal.
622 ** All MI commands now accept an optional "--language" option.
623 Support for this feature can be verified by using the "-list-features"
624 command, which should contain "language-option".
626 ** The new command -info-gdb-mi-command allows the user to determine
627 whether a GDB/MI command is supported or not.
629 ** The "^error" result record returned when trying to execute an undefined
630 GDB/MI command now provides a variable named "code" whose content is the
631 "undefined-command" error code. Support for this feature can be verified
632 by using the "-list-features" command, which should contain
633 "undefined-command-error-code".
635 ** The -trace-save MI command can optionally save trace buffer in Common
638 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
640 ** The command -data-list-register-values now accepts an optional
641 "--skip-unavailable" option. When used, only the available registers
644 ** The new command -trace-frame-collected dumps collected variables,
645 computed expressions, tvars, memory and registers in a traceframe.
647 ** The commands -stack-list-locals, -stack-list-arguments and
648 -stack-list-variables now accept an option "--skip-unavailable".
649 When used, only the available locals or arguments are displayed.
651 ** The -exec-run command now accepts an optional "--start" option.
652 When used, the command follows the same semantics as the "start"
653 command, stopping the program's execution at the start of its
654 main subprogram. Support for this feature can be verified using
655 the "-list-features" command, which should contain
656 "exec-run-start-option".
658 ** The new commands -catch-assert and -catch-exceptions insert
659 catchpoints stopping the program when Ada exceptions are raised.
661 ** The new command -info-ada-exceptions provides the equivalent of
662 the new "info exceptions" command.
664 * New system-wide configuration scripts
665 A GDB installation now provides scripts suitable for use as system-wide
666 configuration scripts for the following systems:
670 * GDB now supports target-assigned range stepping with remote targets.
671 This improves the performance of stepping source lines by reducing
672 the number of control packets from/to GDB. See "New remote packets"
675 * GDB now understands the element 'tvar' in the XML traceframe info.
676 It has the id of the collected trace state variables.
678 * On S/390 targets that provide the transactional-execution feature,
679 the program interruption transaction diagnostic block (TDB) is now
680 represented as a number of additional "registers" in GDB.
686 The vCont packet supports a new 'r' action, that tells the remote
687 stub to step through an address range itself, without GDB
688 involvemement at each single-step.
690 qXfer:libraries-svr4:read's annex
691 The previously unused annex of the qXfer:libraries-svr4:read packet
692 is now used to support passing an argument list. The remote stub
693 reports support for this argument list to GDB's qSupported query.
694 The defined arguments are "start" and "prev", used to reduce work
695 necessary for library list updating, resulting in significant
698 * New features in the GDB remote stub, GDBserver
700 ** GDBserver now supports target-assisted range stepping. Currently
701 enabled on x86/x86_64 GNU/Linux targets.
703 ** GDBserver now adds element 'tvar' in the XML in the reply to
704 'qXfer:traceframe-info:read'. It has the id of the collected
705 trace state variables.
707 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
710 * New 'z' formatter for printing and examining memory, this displays the
711 value as hexadecimal zero padded on the left to the size of the type.
713 * GDB can now use Windows x64 unwinding data.
715 * The "set remotebaud" command has been replaced by "set serial baud".
716 Similarly, "show remotebaud" has been replaced by "show serial baud".
717 The "set remotebaud" and "show remotebaud" commands are still available
718 to provide backward compatibility with older versions of GDB.
720 *** Changes in GDB 7.6
722 * Target record has been renamed to record-full.
723 Record/replay is now enabled with the "record full" command.
724 This also affects settings that are associated with full record/replay
725 that have been moved from "set/show record" to "set/show record full":
727 set|show record full insn-number-max
728 set|show record full stop-at-limit
729 set|show record full memory-query
731 * A new record target "record-btrace" has been added. The new target
732 uses hardware support to record the control-flow of a process. It
733 does not support replaying the execution, but it implements the
734 below new commands for investigating the recorded execution log.
735 This new recording method can be enabled using:
739 The "record-btrace" target is only available on Intel Atom processors
740 and requires a Linux kernel 2.6.32 or later.
742 * Two new commands have been added for record/replay to give information
743 about the recorded execution without having to replay the execution.
744 The commands are only supported by "record btrace".
746 record instruction-history prints the execution history at
747 instruction granularity
749 record function-call-history prints the execution history at
752 * New native configurations
754 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
755 FreeBSD/powerpc powerpc*-*-freebsd
756 x86_64/Cygwin x86_64-*-cygwin*
757 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
761 ARM AArch64 aarch64*-*-elf
762 ARM AArch64 GNU/Linux aarch64*-*-linux
763 Lynx 178 PowerPC powerpc-*-lynx*178
764 x86_64/Cygwin x86_64-*-cygwin*
765 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
767 * If the configured location of system.gdbinit file (as given by the
768 --with-system-gdbinit option at configure time) is in the
769 data-directory (as specified by --with-gdb-datadir at configure
770 time) or in one of its subdirectories, then GDB will look for the
771 system-wide init file in the directory specified by the
772 --data-directory command-line option.
774 * New command line options:
776 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
777 other initialization files, unlike -nx which disables all of them.
779 * Removed command line options
781 -epoch This was used by the gdb mode in Epoch, an ancient fork of
784 * The 'ptype' and 'whatis' commands now accept an argument to control
787 * 'info proc' now works on some core files.
791 ** Vectors can be created with gdb.Type.vector.
793 ** Python's atexit.register now works in GDB.
795 ** Types can be pretty-printed via a Python API.
797 ** Python 3 is now supported (in addition to Python 2.4 or later)
799 ** New class gdb.Architecture exposes GDB's internal representation
800 of architecture in the Python API.
802 ** New method Frame.architecture returns the gdb.Architecture object
803 corresponding to the frame's architecture.
805 * New Python-based convenience functions:
807 ** $_memeq(buf1, buf2, length)
808 ** $_streq(str1, str2)
810 ** $_regex(str, regex)
812 * The 'cd' command now defaults to using '~' (the home directory) if not
815 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
816 default for GCC since November 2000.
818 * The command 'forward-search' can now be abbreviated as 'fo'.
820 * The command 'info tracepoints' can now display 'installed on target'
821 or 'not installed on target' for each non-pending location of tracepoint.
823 * New configure options
825 --enable-libmcheck/--disable-libmcheck
826 By default, development versions are built with -lmcheck on hosts
827 that support it, in order to help track memory corruption issues.
828 Release versions, on the other hand, are built without -lmcheck
829 by default. The --enable-libmcheck/--disable-libmcheck configure
830 options allow the user to override that default.
831 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
832 This configure option allows the user to build GDB with
833 libbabeltrace using which GDB can read Common Trace Format data.
835 * New commands (for set/show, see "New options" below)
838 Catch signals. This is similar to "handle", but allows commands and
839 conditions to be attached.
842 List the BFDs known to GDB.
844 python-interactive [command]
846 Start a Python interactive prompt, or evaluate the optional command
847 and print the result of expressions.
850 "py" is a new alias for "python".
852 enable type-printer [name]...
853 disable type-printer [name]...
854 Enable or disable type printers.
858 ** For the Renesas Super-H architecture, the "regs" command has been removed
859 (has been deprecated in GDB 7.5), and "info all-registers" should be used
864 set print type methods (on|off)
865 show print type methods
866 Control whether method declarations are displayed by "ptype".
867 The default is to show them.
869 set print type typedefs (on|off)
870 show print type typedefs
871 Control whether typedef definitions are displayed by "ptype".
872 The default is to show them.
874 set filename-display basename|relative|absolute
875 show filename-display
876 Control the way in which filenames is displayed.
877 The default is "relative", which preserves previous behavior.
879 set trace-buffer-size
880 show trace-buffer-size
881 Request target to change the size of trace buffer.
883 set remote trace-buffer-size-packet auto|on|off
884 show remote trace-buffer-size-packet
885 Control the use of the remote protocol `QTBuffer:size' packet.
889 Control display of debugging messages related to ARM AArch64.
892 set debug coff-pe-read
893 show debug coff-pe-read
894 Control display of debugging messages related to reading of COFF/PE
899 Control display of debugging messages related to Mach-O symbols
902 set debug notification
903 show debug notification
904 Control display of debugging info for async remote notification.
908 ** Command parameter changes are now notified using new async record
909 "=cmd-param-changed".
910 ** Trace frame changes caused by command "tfind" are now notified using
911 new async record "=traceframe-changed".
912 ** The creation, deletion and modification of trace state variables
913 are now notified using new async records "=tsv-created",
914 "=tsv-deleted" and "=tsv-modified".
915 ** The start and stop of process record are now notified using new
916 async record "=record-started" and "=record-stopped".
917 ** Memory changes are now notified using new async record
919 ** The data-disassemble command response will include a "fullname" field
920 containing the absolute file name when source has been requested.
921 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
922 command, to allow pattern filling of memory areas.
923 ** New commands "-catch-load"/"-catch-unload" added for intercepting
924 library load/unload events.
925 ** The response to breakpoint commands and breakpoint async records
926 includes an "installed" field containing a boolean state about each
927 non-pending tracepoint location is whether installed on target or not.
928 ** Output of the "-trace-status" command includes a "trace-file" field
929 containing the name of the trace file being examined. This field is
930 optional, and only present when examining a trace file.
931 ** The "fullname" field is now always present along with the "file" field,
932 even if the file cannot be found by GDB.
934 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
935 You must have the LZMA library available when configuring GDB for this
936 feature to be enabled. For more information, see:
937 http://fedoraproject.org/wiki/Features/MiniDebugInfo
942 Set the size of trace buffer. The remote stub reports support for this
943 packet to gdb's qSupported query.
946 Enable Branch Trace Store (BTS)-based branch tracing for the current
947 thread. The remote stub reports support for this packet to gdb's
951 Disable branch tracing for the current thread. The remote stub reports
952 support for this packet to gdb's qSupported query.
955 Read the traced branches for the current thread. The remote stub
956 reports support for this packet to gdb's qSupported query.
958 *** Changes in GDB 7.5
960 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
961 for more x32 ABI info.
963 * GDB now supports access to MIPS DSP registers on Linux targets.
965 * GDB now supports debugging microMIPS binaries.
967 * The "info os" command on GNU/Linux can now display information on
968 several new classes of objects managed by the operating system:
969 "info os procgroups" lists process groups
970 "info os files" lists file descriptors
971 "info os sockets" lists internet-domain sockets
972 "info os shm" lists shared-memory regions
973 "info os semaphores" lists semaphores
974 "info os msg" lists message queues
975 "info os modules" lists loaded kernel modules
977 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
978 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
979 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
980 options and inspect the probe arguments using the new $_probe_arg family
981 of convenience variables. You can obtain more information about SystemTap
982 in <http://sourceware.org/systemtap/>.
984 * GDB now supports reversible debugging on ARM, it allows you to
985 debug basic ARM and THUMB instructions, and provides
986 record/replay support.
988 * The option "symbol-reloading" has been deleted as it is no longer used.
992 ** GDB commands implemented in Python can now be put in command class
995 ** The "maint set python print-stack on|off" is now deleted.
997 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
998 apply "flag enum"-style pretty-printing to any enum.
1000 ** gdb.lookup_symbol can now work when there is no current frame.
1002 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1003 the source at which the symbol was defined.
1005 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1006 method 'value'. The former indicates whether the symbol needs a
1007 frame in order to compute its value, and the latter computes the
1010 ** A new method 'referenced_value' on gdb.Value objects which can
1011 dereference pointer as well as C++ reference values.
1013 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1014 which return the global and static blocks (as gdb.Block objects),
1015 of the underlying symbol table, respectively.
1017 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1018 object associated with a PC value.
1020 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1021 of the address range occupied by code for the current source line.
1023 * Go language support.
1024 GDB now supports debugging programs written in the Go programming
1027 * GDBserver now supports stdio connections.
1028 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1030 * The binary "gdbtui" can no longer be built or installed.
1031 Use "gdb -tui" instead.
1033 * GDB will now print "flag" enums specially. A flag enum is one where
1034 all the enumerator values have no bits in common when pairwise
1035 "and"ed. When printing a value whose type is a flag enum, GDB will
1036 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1037 (gdb) print (enum E) 3
1040 * The filename part of a linespec will now match trailing components
1041 of a source file name. For example, "break gcc/expr.c:1000" will
1042 now set a breakpoint in build/gcc/expr.c, but not
1043 build/libcpp/expr.c.
1045 * The "info proc" and "generate-core-file" commands will now also
1046 work on remote targets connected to GDBserver on Linux.
1048 * The command "info catch" has been removed. It has been disabled
1049 since December 2007.
1051 * The "catch exception" and "catch assert" commands now accept
1052 a condition at the end of the command, much like the "break"
1053 command does. For instance:
1055 (gdb) catch exception Constraint_Error if Barrier = True
1057 Previously, it was possible to add a condition to such catchpoints,
1058 but it had to be done as a second step, after the catchpoint had been
1059 created, using the "condition" command.
1061 * The "info static-tracepoint-marker" command will now also work on
1062 native Linux targets with in-process agent.
1064 * GDB can now set breakpoints on inlined functions.
1066 * The .gdb_index section has been updated to include symbols for
1067 inlined functions. GDB will ignore older .gdb_index sections by
1068 default, which could cause symbol files to be loaded more slowly
1069 until their .gdb_index sections can be recreated. The new command
1070 "set use-deprecated-index-sections on" will cause GDB to use any older
1071 .gdb_index sections it finds. This will restore performance, but the
1072 ability to set breakpoints on inlined functions will be lost in symbol
1073 files with older .gdb_index sections.
1075 The .gdb_index section has also been updated to record more information
1076 about each symbol. This speeds up the "info variables", "info functions"
1077 and "info types" commands when used with programs having the .gdb_index
1078 section, as well as speeding up debugging with shared libraries using
1079 the .gdb_index section.
1081 * Ada support for GDB/MI Variable Objects has been added.
1083 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1088 ** New command -info-os is the MI equivalent of "info os".
1090 ** Output logs ("set logging" and related) now include MI output.
1094 ** "set use-deprecated-index-sections on|off"
1095 "show use-deprecated-index-sections on|off"
1096 Controls the use of deprecated .gdb_index sections.
1098 ** "catch load" and "catch unload" can be used to stop when a shared
1099 library is loaded or unloaded, respectively.
1101 ** "enable count" can be used to auto-disable a breakpoint after
1104 ** "info vtbl" can be used to show the virtual method tables for
1105 C++ and Java objects.
1107 ** "explore" and its sub commands "explore value" and "explore type"
1108 can be used to recursively explore values and types of
1109 expressions. These commands are available only if GDB is
1110 configured with '--with-python'.
1112 ** "info auto-load" shows status of all kinds of auto-loaded files,
1113 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1114 sequences of commands files, "info auto-load python-scripts"
1115 shows status of auto-loading Python script files,
1116 "info auto-load local-gdbinit" shows status of loading init file
1117 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1118 status of inferior specific thread debugging shared library loading.
1120 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1121 and "show auto-load-scripts" commands have been deprecated, use their
1122 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1123 and "show auto-load python-scripts" counterparts instead.
1125 ** "dprintf location,format,args..." creates a dynamic printf, which
1126 is basically a breakpoint that does a printf and immediately
1127 resumes your program's execution, so it is like a printf that you
1128 can insert dynamically at runtime instead of at compiletime.
1130 ** "set print symbol"
1132 Controls whether GDB attempts to display the symbol, if any,
1133 corresponding to addresses it prints. This defaults to "on", but
1134 you can set it to "off" to restore GDB's previous behavior.
1136 * Deprecated commands
1138 ** For the Renesas Super-H architecture, the "regs" command has been
1139 deprecated, and "info all-registers" should be used instead.
1143 Renesas RL78 rl78-*-elf
1144 HP OpenVMS ia64 ia64-hp-openvms*
1146 * GDBserver supports evaluation of breakpoint conditions. When
1147 support is advertised by GDBserver, GDB may be told to send the
1148 breakpoint conditions in bytecode form to GDBserver. GDBserver
1149 will only report the breakpoint trigger to GDB when its condition
1154 set mips compression
1155 show mips compression
1156 Select the compressed ISA encoding used in functions that have no symbol
1157 information available. The encoding can be set to either of:
1160 and is updated automatically from ELF file flags if available.
1162 set breakpoint condition-evaluation
1163 show breakpoint condition-evaluation
1164 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1165 GDBserver ("target"). Default option "auto" chooses the most efficient
1167 This option can improve debugger efficiency depending on the speed of the
1171 Disable auto-loading globally.
1174 Show auto-loading setting of all kinds of auto-loaded files.
1176 set auto-load gdb-scripts on|off
1177 show auto-load gdb-scripts
1178 Control auto-loading of GDB canned sequences of commands files.
1180 set auto-load python-scripts on|off
1181 show auto-load python-scripts
1182 Control auto-loading of Python script files.
1184 set auto-load local-gdbinit on|off
1185 show auto-load local-gdbinit
1186 Control loading of init file (.gdbinit) from current directory.
1188 set auto-load libthread-db on|off
1189 show auto-load libthread-db
1190 Control auto-loading of inferior specific thread debugging shared library.
1192 set auto-load scripts-directory <dir1>[:<dir2>...]
1193 show auto-load scripts-directory
1194 Set a list of directories from which to load auto-loaded scripts.
1195 Automatically loaded Python scripts and GDB scripts are located in one
1196 of the directories listed by this option.
1197 The delimiter (':' above) may differ according to the host platform.
1199 set auto-load safe-path <dir1>[:<dir2>...]
1200 show auto-load safe-path
1201 Set a list of directories from which it is safe to auto-load files.
1202 The delimiter (':' above) may differ according to the host platform.
1204 set debug auto-load on|off
1205 show debug auto-load
1206 Control display of debugging info for auto-loading the files above.
1208 set dprintf-style gdb|call|agent
1210 Control the way in which a dynamic printf is performed; "gdb"
1211 requests a GDB printf command, while "call" causes dprintf to call a
1212 function in the inferior. "agent" requests that the target agent
1213 (such as GDBserver) do the printing.
1215 set dprintf-function <expr>
1216 show dprintf-function
1217 set dprintf-channel <expr>
1218 show dprintf-channel
1219 Set the function and optional first argument to the call when using
1220 the "call" style of dynamic printf.
1222 set disconnected-dprintf on|off
1223 show disconnected-dprintf
1224 Control whether agent-style dynamic printfs continue to be in effect
1225 after GDB disconnects.
1227 * New configure options
1229 --with-auto-load-dir
1230 Configure default value for the 'set auto-load scripts-directory'
1231 setting above. It defaults to '$debugdir:$datadir/auto-load',
1232 $debugdir representing global debugging info directories (available
1233 via 'show debug-file-directory') and $datadir representing GDB's data
1234 directory (available via 'show data-directory').
1236 --with-auto-load-safe-path
1237 Configure default value for the 'set auto-load safe-path' setting
1238 above. It defaults to the --with-auto-load-dir setting.
1240 --without-auto-load-safe-path
1241 Set 'set auto-load safe-path' to '/', effectively disabling this
1244 * New remote packets
1246 z0/z1 conditional breakpoints extension
1248 The z0/z1 breakpoint insertion packets have been extended to carry
1249 a list of conditional expressions over to the remote stub depending on the
1250 condition evaluation mode. The use of this extension can be controlled
1251 via the "set remote conditional-breakpoints-packet" command.
1255 Specify the signals which the remote stub may pass to the debugged
1256 program without GDB involvement.
1258 * New command line options
1260 --init-command=FILE, -ix Like --command, -x but execute it
1261 before loading inferior.
1262 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1263 execute it before loading inferior.
1265 *** Changes in GDB 7.4
1267 * GDB now handles ambiguous linespecs more consistently; the existing
1268 FILE:LINE support has been expanded to other types of linespecs. A
1269 breakpoint will now be set on all matching locations in all
1270 inferiors, and locations will be added or removed according to
1273 * GDB now allows you to skip uninteresting functions and files when
1274 stepping with the "skip function" and "skip file" commands.
1276 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1277 and "show remote hardware-watchpoint-length-limit". These allows to
1278 set or show the maximum length limit (in bytes) of a remote
1279 target hardware watchpoint.
1281 This allows e.g. to use "unlimited" hardware watchpoints with the
1282 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1283 watchpoints are slower than real hardware watchpoints but are
1284 significantly faster than gdb software watchpoints.
1288 ** The register_pretty_printer function in module gdb.printing now takes
1289 an optional `replace' argument. If True, the new printer replaces any
1292 ** The "maint set python print-stack on|off" command has been
1293 deprecated and will be deleted in GDB 7.5.
1294 A new command: "set python print-stack none|full|message" has
1295 replaced it. Additionally, the default for "print-stack" is
1296 now "message", which just prints the error message without
1299 ** A prompt substitution hook (prompt_hook) is now available to the
1302 ** A new Python module, gdb.prompt has been added to the GDB Python
1303 modules library. This module provides functionality for
1304 escape sequences in prompts (used by set/show
1305 extended-prompt). These escape sequences are replaced by their
1306 corresponding value.
1308 ** Python commands and convenience-functions located in
1309 'data-directory'/python/gdb/command and
1310 'data-directory'/python/gdb/function are now automatically loaded
1313 ** Blocks now provide four new attributes. global_block and
1314 static_block will return the global and static blocks
1315 respectively. is_static and is_global are boolean attributes
1316 that indicate if the block is one of those two types.
1318 ** Symbols now provide the "type" attribute, the type of the symbol.
1320 ** The "gdb.breakpoint" function has been deprecated in favor of
1323 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1324 of a function. This class is based on the "finish" command
1325 available in the CLI.
1327 ** Type objects for struct and union types now allow access to
1328 the fields using standard Python dictionary (mapping) methods.
1329 For example, "some_type['myfield']" now works, as does
1330 "some_type.items()".
1332 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1335 ** A new function, "deep_items" has been added to the gdb.types
1336 module in the GDB Python modules library. This function returns
1337 an iterator over the fields of a struct or union type. Unlike
1338 the standard Python "iteritems" method, it will recursively traverse
1339 any anonymous fields.
1343 ** "*stopped" events can report several new "reason"s, such as
1346 ** Breakpoint changes are now notified using new async records, like
1347 "=breakpoint-modified".
1349 ** New command -ada-task-info.
1351 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1352 $sdir specifies the default system locations of shared libraries.
1353 $pdir specifies the directory where the libpthread used by the application
1356 GDB no longer looks in $sdir and $pdir after it has searched the directories
1357 mentioned in libthread-db-search-path. If you want to search those
1358 directories, they must be specified in libthread-db-search-path.
1359 The default value of libthread-db-search-path on GNU/Linux and Solaris
1360 systems is now "$sdir:$pdir".
1362 $pdir is not supported by gdbserver, it is currently ignored.
1363 $sdir is supported by gdbserver.
1365 * New configure option --with-iconv-bin.
1366 When using the internationalization support like the one in the GNU C
1367 library, GDB will invoke the "iconv" program to get a list of supported
1368 character sets. If this program lives in a non-standard location, one can
1369 use this option to specify where to find it.
1371 * When natively debugging programs on PowerPC BookE processors running
1372 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1373 watchpoints, which specify a mask in addition to an address to watch.
1374 The mask specifies that some bits of an address (the bits which are
1375 reset in the mask) should be ignored when matching the address accessed
1376 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1377 section in the user manual for more details.
1379 * The new option --once causes GDBserver to stop listening for connections once
1380 the first connection is made. The listening port used by GDBserver will
1381 become available after that.
1383 * New commands "info macros" and "alias" have been added.
1385 * New function parameters suffix @entry specifies value of function parameter
1386 at the time the function got called. Entry values are available only since
1392 "!" is now an alias of the "shell" command.
1393 Note that no space is needed between "!" and SHELL COMMAND.
1397 watch EXPRESSION mask MASK_VALUE
1398 The watch command now supports the mask argument which allows creation
1399 of masked watchpoints, if the current architecture supports this feature.
1401 info auto-load-scripts [REGEXP]
1402 This command was formerly named "maintenance print section-scripts".
1403 It is now generally useful and is no longer a maintenance-only command.
1405 info macro [-all] [--] MACRO
1406 The info macro command has new options `-all' and `--'. The first for
1407 printing all definitions of a macro. The second for explicitly specifying
1408 the end of arguments and the beginning of the macro name in case the macro
1409 name starts with a hyphen.
1411 collect[/s] EXPRESSIONS
1412 The tracepoint collect command now takes an optional modifier "/s"
1413 that directs it to dereference pointer-to-character types and
1414 collect the bytes of memory up to a zero byte. The behavior is
1415 similar to what you see when you use the regular print command on a
1416 string. An optional integer following the "/s" sets a bound on the
1417 number of bytes that will be collected.
1420 The trace start command now interprets any supplied arguments as a
1421 note to be recorded with the trace run, with an effect similar to
1422 setting the variable trace-notes.
1425 The trace stop command now interprets any arguments as a note to be
1426 mentioned along with the tstatus report that the trace was stopped
1427 with a command. The effect is similar to setting the variable
1430 * Tracepoints can now be enabled and disabled at any time after a trace
1431 experiment has been started using the standard "enable" and "disable"
1432 commands. It is now possible to start a trace experiment with no enabled
1433 tracepoints; GDB will display a warning, but will allow the experiment to
1434 begin, assuming that tracepoints will be enabled as needed while the trace
1437 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1438 locations with 4-byte instructions, when they were previously
1439 limited to locations with instructions of 5 bytes or longer.
1443 set debug dwarf2-read
1444 show debug dwarf2-read
1445 Turns on or off display of debugging messages related to reading
1446 DWARF debug info. The default is off.
1448 set debug symtab-create
1449 show debug symtab-create
1450 Turns on or off display of debugging messages related to symbol table
1451 creation. The default is off.
1454 show extended-prompt
1455 Set the GDB prompt, and allow escape sequences to be inserted to
1456 display miscellaneous information (see 'help set extended-prompt'
1457 for the list of sequences). This prompt (and any information
1458 accessed through the escape sequences) is updated every time the
1459 prompt is displayed.
1461 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1462 show print entry-values
1463 Set printing of frame argument values at function entry. In some cases
1464 GDB can determine the value of function argument which was passed by the
1465 function caller, even if the value was modified inside the called function.
1467 set debug entry-values
1468 show debug entry-values
1469 Control display of debugging info for determining frame argument values at
1470 function entry and virtual tail call frames.
1472 set basenames-may-differ
1473 show basenames-may-differ
1474 Set whether a source file may have multiple base names.
1475 (A "base name" is the name of a file with the directory part removed.
1476 Example: The base name of "/home/user/hello.c" is "hello.c".)
1477 If set, GDB will canonicalize file names (e.g., expand symlinks)
1478 before comparing them. Canonicalization is an expensive operation,
1479 but it allows the same file be known by more than one base name.
1480 If not set (the default), all source files are assumed to have just
1481 one base name, and gdb will do file name comparisons more efficiently.
1487 Set a user name and notes for the current and any future trace runs.
1488 This is useful for long-running and/or disconnected traces, to
1489 inform others (or yourself) as to who is running the trace, supply
1490 contact information, or otherwise explain what is going on.
1492 set trace-stop-notes
1493 show trace-stop-notes
1494 Set a note attached to the trace run, that is displayed when the
1495 trace has been stopped by a tstop command. This is useful for
1496 instance as an explanation, if you are stopping a trace run that was
1497 started by someone else.
1499 * New remote packets
1503 Dynamically enable a tracepoint in a started trace experiment.
1507 Dynamically disable a tracepoint in a started trace experiment.
1511 Set the user and notes of the trace run.
1515 Query the current status of a tracepoint.
1519 Query the minimum length of instruction at which a fast tracepoint may
1522 * Dcache size (number of lines) and line-size are now runtime-configurable
1523 via "set dcache line" and "set dcache line-size" commands.
1527 Texas Instruments TMS320C6x tic6x-*-*
1531 Renesas RL78 rl78-*-elf
1533 *** Changes in GDB 7.3.1
1535 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1537 *** Changes in GDB 7.3
1539 * GDB has a new command: "thread find [REGEXP]".
1540 It finds the thread id whose name, target id, or thread extra info
1541 matches the given regular expression.
1543 * The "catch syscall" command now works on mips*-linux* targets.
1545 * The -data-disassemble MI command now supports modes 2 and 3 for
1546 dumping the instruction opcodes.
1548 * New command line options
1550 -data-directory DIR Specify DIR as the "data-directory".
1551 This is mostly for testing purposes.
1553 * The "maint set python auto-load on|off" command has been renamed to
1554 "set auto-load-scripts on|off".
1556 * GDB has a new command: "set directories".
1557 It is like the "dir" command except that it replaces the
1558 source path list instead of augmenting it.
1560 * GDB now understands thread names.
1562 On GNU/Linux, "info threads" will display the thread name as set by
1563 prctl or pthread_setname_np.
1565 There is also a new command, "thread name", which can be used to
1566 assign a name internally for GDB to display.
1569 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1570 has been integrated into GDB.
1574 ** The function gdb.Write now accepts an optional keyword 'stream'.
1575 This keyword, when provided, will direct the output to either
1576 stdout, stderr, or GDB's logging output.
1578 ** Parameters can now be be sub-classed in Python, and in particular
1579 you may implement the get_set_doc and get_show_doc functions.
1580 This improves how Parameter set/show documentation is processed
1581 and allows for more dynamic content.
1583 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1584 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1585 have an is_valid method.
1587 ** Breakpoints can now be sub-classed in Python, and in particular
1588 you may implement a 'stop' function that is executed each time
1589 the inferior reaches that breakpoint.
1591 ** New function gdb.lookup_global_symbol looks up a global symbol.
1593 ** GDB values in Python are now callable if the value represents a
1594 function. For example, if 'some_value' represents a function that
1595 takes two integer parameters and returns a value, you can call
1596 that function like so:
1598 result = some_value (10,20)
1600 ** Module gdb.types has been added.
1601 It contains a collection of utilities for working with gdb.Types objects:
1602 get_basic_type, has_field, make_enum_dict.
1604 ** Module gdb.printing has been added.
1605 It contains utilities for writing and registering pretty-printers.
1606 New classes: PrettyPrinter, SubPrettyPrinter,
1607 RegexpCollectionPrettyPrinter.
1608 New function: register_pretty_printer.
1610 ** New commands "info pretty-printers", "enable pretty-printer" and
1611 "disable pretty-printer" have been added.
1613 ** gdb.parameter("directories") is now available.
1615 ** New function gdb.newest_frame returns the newest frame in the
1618 ** The gdb.InferiorThread class has a new "name" attribute. This
1619 holds the thread's name.
1621 ** Python Support for Inferior events.
1622 Python scripts can add observers to be notified of events
1623 occurring in the process being debugged.
1624 The following events are currently supported:
1625 - gdb.events.cont Continue event.
1626 - gdb.events.exited Inferior exited event.
1627 - gdb.events.stop Signal received, and Breakpoint hit events.
1631 ** GDB now puts template parameters in scope when debugging in an
1632 instantiation. For example, if you have:
1634 template<int X> int func (void) { return X; }
1636 then if you step into func<5>, "print X" will show "5". This
1637 feature requires proper debuginfo support from the compiler; it
1638 was added to GCC 4.5.
1640 ** The motion commands "next", "finish", "until", and "advance" now
1641 work better when exceptions are thrown. In particular, GDB will
1642 no longer lose control of the inferior; instead, the GDB will
1643 stop the inferior at the point at which the exception is caught.
1644 This functionality requires a change in the exception handling
1645 code that was introduced in GCC 4.5.
1647 * GDB now follows GCC's rules on accessing volatile objects when
1648 reading or writing target state during expression evaluation.
1649 One notable difference to prior behavior is that "print x = 0"
1650 no longer generates a read of x; the value of the assignment is
1651 now always taken directly from the value being assigned.
1653 * GDB now has some support for using labels in the program's source in
1654 linespecs. For instance, you can use "advance label" to continue
1655 execution to a label.
1657 * GDB now has support for reading and writing a new .gdb_index
1658 section. This section holds a fast index of DWARF debugging
1659 information and can be used to greatly speed up GDB startup and
1660 operation. See the documentation for `save gdb-index' for details.
1662 * The "watch" command now accepts an optional "-location" argument.
1663 When used, this causes GDB to watch the memory referred to by the
1664 expression. Such a watchpoint is never deleted due to it going out
1667 * GDB now supports thread debugging of core dumps on GNU/Linux.
1669 GDB now activates thread debugging using the libthread_db library
1670 when debugging GNU/Linux core dumps, similarly to when debugging
1671 live processes. As a result, when debugging a core dump file, GDB
1672 is now able to display pthread_t ids of threads. For example, "info
1673 threads" shows the same output as when debugging the process when it
1674 was live. In earlier releases, you'd see something like this:
1677 * 1 LWP 6780 main () at main.c:10
1679 While now you see this:
1682 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1684 It is also now possible to inspect TLS variables when debugging core
1687 When debugging a core dump generated on a machine other than the one
1688 used to run GDB, you may need to point GDB at the correct
1689 libthread_db library with the "set libthread-db-search-path"
1690 command. See the user manual for more details on this command.
1692 * When natively debugging programs on PowerPC BookE processors running
1693 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1694 which stop execution of the inferior whenever it executes an instruction
1695 at any address within the specified range. See the "PowerPC Embedded"
1696 section in the user manual for more details.
1698 * New features in the GDB remote stub, GDBserver
1700 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1701 and i686 LynxOS (version 5.x).
1703 ** GDBserver is now supported on Blackfin Linux.
1705 * New native configurations
1707 ia64 HP-UX ia64-*-hpux*
1711 Analog Devices, Inc. Blackfin Processor bfin-*
1713 * Ada task switching is now supported on sparc-elf targets when
1714 debugging a program using the Ravenscar Profile. For more information,
1715 see the "Tasking Support when using the Ravenscar Profile" section
1716 in the GDB user manual.
1718 * Guile support was removed.
1720 * New features in the GNU simulator
1722 ** The --map-info flag lists all known core mappings.
1724 ** CFI flashes may be simulated via the "cfi" device.
1726 *** Changes in GDB 7.2
1728 * Shared library support for remote targets by default
1730 When GDB is configured for a generic, non-OS specific target, like
1731 for example, --target=arm-eabi or one of the many *-*-elf targets,
1732 GDB now queries remote stubs for loaded shared libraries using the
1733 `qXfer:libraries:read' packet. Previously, shared library support
1734 was always disabled for such configurations.
1738 ** Argument Dependent Lookup (ADL)
1740 In C++ ADL lookup directs function search to the namespaces of its
1741 arguments even if the namespace has not been imported.
1751 Here the compiler will search for `foo' in the namespace of 'b'
1752 and find A::foo. GDB now supports this. This construct is commonly
1753 used in the Standard Template Library for operators.
1755 ** Improved User Defined Operator Support
1757 In addition to member operators, GDB now supports lookup of operators
1758 defined in a namespace and imported with a `using' directive, operators
1759 defined in the global scope, operators imported implicitly from an
1760 anonymous namespace, and the ADL operators mentioned in the previous
1762 GDB now also supports proper overload resolution for all the previously
1763 mentioned flavors of operators.
1765 ** static const class members
1767 Printing of static const class members that are initialized in the
1768 class definition has been fixed.
1770 * Windows Thread Information Block access.
1772 On Windows targets, GDB now supports displaying the Windows Thread
1773 Information Block (TIB) structure. This structure is visible either
1774 by using the new command `info w32 thread-information-block' or, by
1775 dereferencing the new convenience variable named `$_tlb', a
1776 thread-specific pointer to the TIB. This feature is also supported
1777 when remote debugging using GDBserver.
1779 * Static tracepoints
1781 Static tracepoints are calls in the user program into a tracing
1782 library. One such library is a port of the LTTng kernel tracer to
1783 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1784 When debugging with GDBserver, GDB now supports combining the GDB
1785 tracepoint machinery with such libraries. For example: the user can
1786 use GDB to probe a static tracepoint marker (a call from the user
1787 program into the tracing library) with the new "strace" command (see
1788 "New commands" below). This creates a "static tracepoint" in the
1789 breakpoint list, that can be manipulated with the same feature set
1790 as fast and regular tracepoints. E.g., collect registers, local and
1791 global variables, collect trace state variables, and define
1792 tracepoint conditions. In addition, the user can collect extra
1793 static tracepoint marker specific data, by collecting the new
1794 $_sdata internal variable. When analyzing the trace buffer, you can
1795 inspect $_sdata like any other variable available to GDB. For more
1796 information, see the "Tracepoints" chapter in GDB user manual. New
1797 remote packets have been defined to support static tracepoints, see
1798 the "New remote packets" section below.
1800 * Better reconstruction of tracepoints after disconnected tracing
1802 GDB will attempt to download the original source form of tracepoint
1803 definitions when starting a trace run, and then will upload these
1804 upon reconnection to the target, resulting in a more accurate
1805 reconstruction of the tracepoints that are in use on the target.
1809 You can now exercise direct control over the ways that GDB can
1810 affect your program. For instance, you can disallow the setting of
1811 breakpoints, so that the program can run continuously (assuming
1812 non-stop mode). In addition, the "observer" variable is available
1813 to switch all of the different controls; in observer mode, GDB
1814 cannot affect the target's behavior at all, which is useful for
1815 tasks like diagnosing live systems in the field.
1817 * The new convenience variable $_thread holds the number of the
1820 * New remote packets
1824 Return the address of the Windows Thread Information Block of a given thread.
1828 In response to several of the tracepoint packets, the target may now
1829 also respond with a number of intermediate `qRelocInsn' request
1830 packets before the final result packet, to have GDB handle
1831 relocating an instruction to execute at a different address. This
1832 is particularly useful for stubs that support fast tracepoints. GDB
1833 reports support for this feature in the qSupported packet.
1837 List static tracepoint markers in the target program.
1841 List static tracepoint markers at a given address in the target
1844 qXfer:statictrace:read
1846 Read the static trace data collected (by a `collect $_sdata'
1847 tracepoint action). The remote stub reports support for this packet
1848 to gdb's qSupported query.
1852 Send the current settings of GDB's permission flags.
1856 Send part of the source (textual) form of a tracepoint definition,
1857 which includes location, conditional, and action list.
1859 * The source command now accepts a -s option to force searching for the
1860 script in the source search path even if the script name specifies
1863 * New features in the GDB remote stub, GDBserver
1865 - GDBserver now support tracepoints (including fast tracepoints, and
1866 static tracepoints). The feature is currently supported by the
1867 i386-linux and amd64-linux builds. See the "Tracepoints support
1868 in gdbserver" section in the manual for more information.
1870 GDBserver JIT compiles the tracepoint's conditional agent
1871 expression bytecode into native code whenever possible for low
1872 overhead dynamic tracepoints conditionals. For such tracepoints,
1873 an expression that examines program state is evaluated when the
1874 tracepoint is reached, in order to determine whether to capture
1875 trace data. If the condition is simple and false, processing the
1876 tracepoint finishes very quickly and no data is gathered.
1878 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1879 for static tracepoints support.
1881 - GDBserver now supports x86_64 Windows 64-bit debugging.
1883 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1884 it understands register description.
1886 * The --batch flag now disables pagination and queries.
1888 * X86 general purpose registers
1890 GDB now supports reading/writing byte, word and double-word x86
1891 general purpose registers directly. This means you can use, say,
1892 $ah or $ax to refer, respectively, to the byte register AH and
1893 16-bit word register AX that are actually portions of the 32-bit
1894 register EAX or 64-bit register RAX.
1896 * The `commands' command now accepts a range of breakpoints to modify.
1897 A plain `commands' following a command that creates multiple
1898 breakpoints affects all the breakpoints set by that command. This
1899 applies to breakpoints set by `rbreak', and also applies when a
1900 single `break' command creates multiple breakpoints (e.g.,
1901 breakpoints on overloaded c++ functions).
1903 * The `rbreak' command now accepts a filename specification as part of
1904 its argument, limiting the functions selected by the regex to those
1905 in the specified file.
1907 * Support for remote debugging Windows and SymbianOS shared libraries
1908 from Unix hosts has been improved. Non Windows GDB builds now can
1909 understand target reported file names that follow MS-DOS based file
1910 system semantics, such as file names that include drive letters and
1911 use the backslash character as directory separator. This makes it
1912 possible to transparently use the "set sysroot" and "set
1913 solib-search-path" on Unix hosts to point as host copies of the
1914 target's shared libraries. See the new command "set
1915 target-file-system-kind" described below, and the "Commands to
1916 specify files" section in the user manual for more information.
1920 eval template, expressions...
1921 Convert the values of one or more expressions under the control
1922 of the string template to a command line, and call it.
1924 set target-file-system-kind unix|dos-based|auto
1925 show target-file-system-kind
1926 Set or show the assumed file system kind for target reported file
1929 save breakpoints <filename>
1930 Save all current breakpoint definitions to a file suitable for use
1931 in a later debugging session. To read the saved breakpoint
1932 definitions, use the `source' command.
1934 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1937 info static-tracepoint-markers
1938 Display information about static tracepoint markers in the target.
1940 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1941 Define a static tracepoint by probing a marker at the given
1942 function, line, address, or marker ID.
1946 Enable and disable observer mode.
1948 set may-write-registers on|off
1949 set may-write-memory on|off
1950 set may-insert-breakpoints on|off
1951 set may-insert-tracepoints on|off
1952 set may-insert-fast-tracepoints on|off
1953 set may-interrupt on|off
1954 Set individual permissions for GDB effects on the target. Note that
1955 some of these settings can have undesirable or surprising
1956 consequences, particularly when changed in the middle of a session.
1957 For instance, disabling the writing of memory can prevent
1958 breakpoints from being inserted, cause single-stepping to fail, or
1959 even crash your program, if you disable after breakpoints have been
1960 inserted. However, GDB should not crash.
1962 set record memory-query on|off
1963 show record memory-query
1964 Control whether to stop the inferior if memory changes caused
1965 by an instruction cannot be recorded.
1970 The disassemble command now supports "start,+length" form of two arguments.
1974 ** GDB now provides a new directory location, called the python directory,
1975 where Python scripts written for GDB can be installed. The location
1976 of that directory is <data-directory>/python, where <data-directory>
1977 is the GDB data directory. For more details, see section `Scripting
1978 GDB using Python' in the manual.
1980 ** The GDB Python API now has access to breakpoints, symbols, symbol
1981 tables, program spaces, inferiors, threads and frame's code blocks.
1982 Additionally, GDB Parameters can now be created from the API, and
1983 manipulated via set/show in the CLI.
1985 ** New functions gdb.target_charset, gdb.target_wide_charset,
1986 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1988 ** New exception gdb.GdbError.
1990 ** Pretty-printers are now also looked up in the current program space.
1992 ** Pretty-printers can now be individually enabled and disabled.
1994 ** GDB now looks for names of Python scripts to auto-load in a
1995 special section named `.debug_gdb_scripts', in addition to looking
1996 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1998 * Tracepoint actions were unified with breakpoint commands. In particular,
1999 there are no longer differences in "info break" output for breakpoints and
2000 tracepoints and the "commands" command can be used for both tracepoints and
2001 regular breakpoints.
2005 ARM Symbian arm*-*-symbianelf*
2007 * D language support.
2008 GDB now supports debugging programs written in the D programming
2011 * GDB now supports the extended ptrace interface for PowerPC which is
2012 available since Linux kernel version 2.6.34. This automatically enables
2013 any hardware breakpoints and additional hardware watchpoints available in
2014 the processor. The old ptrace interface exposes just one hardware
2015 watchpoint and no hardware breakpoints.
2017 * GDB is now able to use the Data Value Compare (DVC) register available on
2018 embedded PowerPC processors to implement in hardware simple watchpoint
2019 conditions of the form:
2021 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2023 This works in native GDB running on Linux kernels with the extended ptrace
2024 interface mentioned above.
2026 *** Changes in GDB 7.1
2030 ** Namespace Support
2032 GDB now supports importing of namespaces in C++. This enables the
2033 user to inspect variables from imported namespaces. Support for
2034 namepace aliasing has also been added. So, if a namespace is
2035 aliased in the current scope (e.g. namepace C=A; ) the user can
2036 print variables using the alias (e.g. (gdb) print C::x).
2040 All known bugs relating to the printing of virtual base class were
2041 fixed. It is now possible to call overloaded static methods using a
2046 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2047 and reinterpret_cast<> are now handled by the C++ expression parser.
2051 Xilinx MicroBlaze microblaze-*-*
2056 Xilinx MicroBlaze microblaze
2059 * Multi-program debugging.
2061 GDB now has support for multi-program (a.k.a. multi-executable or
2062 multi-exec) debugging. This allows for debugging multiple inferiors
2063 simultaneously each running a different program under the same GDB
2064 session. See "Debugging Multiple Inferiors and Programs" in the
2065 manual for more information. This implied some user visible changes
2066 in the multi-inferior support. For example, "info inferiors" now
2067 lists inferiors that are not running yet or that have exited
2068 already. See also "New commands" and "New options" below.
2070 * New tracing features
2072 GDB's tracepoint facility now includes several new features:
2074 ** Trace state variables
2076 GDB tracepoints now include support for trace state variables, which
2077 are variables managed by the target agent during a tracing
2078 experiment. They are useful for tracepoints that trigger each
2079 other, so for instance one tracepoint can count hits in a variable,
2080 and then a second tracepoint has a condition that is true when the
2081 count reaches a particular value. Trace state variables share the
2082 $-syntax of GDB convenience variables, and can appear in both
2083 tracepoint actions and condition expressions. Use the "tvariable"
2084 command to create, and "info tvariables" to view; see "Trace State
2085 Variables" in the manual for more detail.
2089 GDB now includes an option for defining fast tracepoints, which
2090 targets may implement more efficiently, such as by installing a jump
2091 into the target agent rather than a trap instruction. The resulting
2092 speedup can be by two orders of magnitude or more, although the
2093 tradeoff is that some program locations on some target architectures
2094 might not allow fast tracepoint installation, for instance if the
2095 instruction to be replaced is shorter than the jump. To request a
2096 fast tracepoint, use the "ftrace" command, with syntax identical to
2097 the regular trace command.
2099 ** Disconnected tracing
2101 It is now possible to detach GDB from the target while it is running
2102 a trace experiment, then reconnect later to see how the experiment
2103 is going. In addition, a new variable disconnected-tracing lets you
2104 tell the target agent whether to continue running a trace if the
2105 connection is lost unexpectedly.
2109 GDB now has the ability to save the trace buffer into a file, and
2110 then use that file as a target, similarly to you can do with
2111 corefiles. You can select trace frames, print data that was
2112 collected in them, and use tstatus to display the state of the
2113 tracing run at the moment that it was saved. To create a trace
2114 file, use "tsave <filename>", and to use it, do "target tfile
2117 ** Circular trace buffer
2119 You can ask the target agent to handle the trace buffer as a
2120 circular buffer, discarding the oldest trace frames to make room for
2121 newer ones, by setting circular-trace-buffer to on. This feature may
2122 not be available for all target agents.
2127 The disassemble command, when invoked with two arguments, now requires
2128 the arguments to be comma-separated.
2131 The info variables command now displays variable definitions. Files
2132 which only declare a variable are not shown.
2135 The source command is now capable of sourcing Python scripts.
2136 This feature is dependent on the debugger being build with Python
2139 Related to this enhancement is also the introduction of a new command
2140 "set script-extension" (see below).
2142 * New commands (for set/show, see "New options" below)
2144 record save [<FILENAME>]
2145 Save a file (in core file format) containing the process record
2146 execution log for replay debugging at a later time.
2148 record restore <FILENAME>
2149 Restore the process record execution log that was saved at an
2150 earlier time, for replay debugging.
2152 add-inferior [-copies <N>] [-exec <FILENAME>]
2155 clone-inferior [-copies <N>] [ID]
2156 Make a new inferior ready to execute the same program another
2157 inferior has loaded.
2162 maint info program-spaces
2163 List the program spaces loaded into GDB.
2165 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2166 show remote interrupt-sequence
2167 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2168 as the sequence to the remote target in order to interrupt the execution.
2169 Ctrl-C is a default. Some system prefers BREAK which is high level of
2170 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2171 Magic SysRq g. It is BREAK signal and character 'g'.
2173 set remote interrupt-on-connect [on | off]
2174 show remote interrupt-on-connect
2175 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2176 remote target when gdb connects to it. This is needed when you debug
2179 set remotebreak [on | off]
2181 Deprecated. Use "set/show remote interrupt-sequence" instead.
2183 tvariable $NAME [ = EXP ]
2184 Create or modify a trace state variable.
2187 List trace state variables and their values.
2189 delete tvariable $NAME ...
2190 Delete one or more trace state variables.
2193 Evaluate the given expressions without collecting anything into the
2194 trace buffer. (Valid in tracepoint actions only.)
2196 ftrace FN / FILE:LINE / *ADDR
2197 Define a fast tracepoint at the given function, line, or address.
2199 * New expression syntax
2201 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2202 GDB now parses 0b101010 identically with 42.
2206 set follow-exec-mode new|same
2207 show follow-exec-mode
2208 Control whether GDB reuses the same inferior across an exec call or
2209 creates a new one. This is useful to be able to restart the old
2210 executable after the inferior having done an exec call.
2212 set default-collect EXPR, ...
2213 show default-collect
2214 Define a list of expressions to be collected at each tracepoint.
2215 This is a useful way to ensure essential items are not overlooked,
2216 such as registers or a critical global variable.
2218 set disconnected-tracing
2219 show disconnected-tracing
2220 If set to 1, the target is instructed to continue tracing if it
2221 loses its connection to GDB. If 0, the target is to stop tracing
2224 set circular-trace-buffer
2225 show circular-trace-buffer
2226 If set to on, the target is instructed to use a circular trace buffer
2227 and discard the oldest trace frames instead of stopping the trace due
2228 to a full trace buffer. If set to off, the trace stops when the buffer
2229 fills up. Some targets may not support this.
2231 set script-extension off|soft|strict
2232 show script-extension
2233 If set to "off", the debugger does not perform any script language
2234 recognition, and all sourced files are assumed to be GDB scripts.
2235 If set to "soft" (the default), files are sourced according to
2236 filename extension, falling back to GDB scripts if the first
2238 If set to "strict", files are sourced according to filename extension.
2240 set ada trust-PAD-over-XVS on|off
2241 show ada trust-PAD-over-XVS
2242 If off, activate a workaround against a bug in the debugging information
2243 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2244 the GCC sources for more information about the GNAT encoding and
2245 PAD types in particular). It is always safe to set this option to
2246 off, but this introduces a slight performance penalty. The default
2249 * Python API Improvements
2251 ** GDB provides the new class gdb.LazyString. This is useful in
2252 some pretty-printing cases. The new method gdb.Value.lazy_string
2253 provides a simple way to create objects of this type.
2255 ** The fields returned by gdb.Type.fields now have an
2256 `is_base_class' attribute.
2258 ** The new method gdb.Type.range returns the range of an array type.
2260 ** The new method gdb.parse_and_eval can be used to parse and
2261 evaluate an expression.
2263 * New remote packets
2266 Define a trace state variable.
2269 Get the current value of a trace state variable.
2272 Set desired tracing behavior upon disconnection.
2275 Set the trace buffer to be linear or circular.
2278 Get data about the tracepoints currently in use.
2282 Process record now works correctly with hardware watchpoints.
2284 Multiple bug fixes have been made to the mips-irix port, making it
2285 much more reliable. In particular:
2286 - Debugging threaded applications is now possible again. Previously,
2287 GDB would hang while starting the program, or while waiting for
2288 the program to stop at a breakpoint.
2289 - Attaching to a running process no longer hangs.
2290 - An error occurring while loading a core file has been fixed.
2291 - Changing the value of the PC register now works again. This fixes
2292 problems observed when using the "jump" command, or when calling
2293 a function from GDB, or even when assigning a new value to $pc.
2294 - With the "finish" and "return" commands, the return value for functions
2295 returning a small array is now correctly printed.
2296 - It is now possible to break on shared library code which gets executed
2297 during a shared library init phase (code executed while executing
2298 their .init section). Previously, the breakpoint would have no effect.
2299 - GDB is now able to backtrace through the signal handler for
2300 non-threaded programs.
2302 PIE (Position Independent Executable) programs debugging is now supported.
2303 This includes debugging execution of PIC (Position Independent Code) shared
2304 libraries although for that, it should be possible to run such libraries as an
2307 *** Changes in GDB 7.0
2309 * GDB now has an interface for JIT compilation. Applications that
2310 dynamically generate code can create symbol files in memory and register
2311 them with GDB. For users, the feature should work transparently, and
2312 for JIT developers, the interface is documented in the GDB manual in the
2313 "JIT Compilation Interface" chapter.
2315 * Tracepoints may now be conditional. The syntax is as for
2316 breakpoints; either an "if" clause appended to the "trace" command,
2317 or the "condition" command is available. GDB sends the condition to
2318 the target for evaluation using the same bytecode format as is used
2319 for tracepoint actions.
2321 * The disassemble command now supports: an optional /r modifier, print the
2322 raw instructions in hex as well as in symbolic form, and an optional /m
2323 modifier to print mixed source+assembly.
2325 * Process record and replay
2327 In a architecture environment that supports ``process record and
2328 replay'', ``process record and replay'' target can record a log of
2329 the process execution, and replay it with both forward and reverse
2332 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2333 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2334 set execution-direction {forward|reverse}, for targets that support
2337 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2338 feature is available with a native GDB running on kernel version
2341 * GDB now has support for multi-byte and wide character sets on the
2342 target. Strings whose character type is wchar_t, char16_t, or
2343 char32_t are now correctly printed. GDB supports wide- and unicode-
2344 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2345 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2346 `printf'. This feature requires iconv to work properly; if your
2347 system does not have a working iconv, GDB can use GNU libiconv. See
2348 the installation instructions for more information.
2350 * GDB now supports automatic retrieval of shared library files from
2351 remote targets. To use this feature, specify a system root that begins
2352 with the `remote:' prefix, either via the `set sysroot' command or via
2353 the `--with-sysroot' configure-time option.
2355 * "info sharedlibrary" now takes an optional regex of libraries to show,
2356 and it now reports if a shared library has no debugging information.
2358 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2359 now complete on file names.
2361 * When completing in expressions, gdb will attempt to limit
2362 completions to allowable structure or union fields, where appropriate.
2363 For instance, consider:
2365 # struct example { int f1; double f2; };
2366 # struct example variable;
2369 If the user types TAB at the end of this command line, the available
2370 completions will be "f1" and "f2".
2372 * Inlined functions are now supported. They show up in backtraces, and
2373 the "step", "next", and "finish" commands handle them automatically.
2375 * GDB now supports the token-splicing (##) and stringification (#)
2376 operators when expanding macros. It also supports variable-arity
2379 * GDB now supports inspecting extra signal information, exported by
2380 the new $_siginfo convenience variable. The feature is currently
2381 implemented on linux ARM, i386 and amd64.
2383 * GDB can now display the VFP floating point registers and NEON vector
2384 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2385 can provide these registers (requires Linux 2.6.30 or later). Remote
2386 and simulator targets may also provide them.
2388 * New remote packets
2391 Search memory for a sequence of bytes.
2394 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2395 operation over reliable transport links. Use of this packet is
2396 controlled by the `set remote noack-packet' command.
2399 Kill the process with the specified process ID. Use this in preference
2400 to `k' when multiprocess protocol extensions are supported.
2403 Obtains additional operating system information
2407 Read or write additional signal information.
2409 * Removed remote protocol undocumented extension
2411 An undocumented extension to the remote protocol's `S' stop reply
2412 packet that permited the stub to pass a process id was removed.
2413 Remote servers should use the `T' stop reply packet instead.
2415 * GDB now supports multiple function calling conventions according to the
2416 DWARF-2 DW_AT_calling_convention function attribute.
2418 * The SH target utilizes the aforementioned change to distinguish between gcc
2419 and Renesas calling convention. It also adds the new CLI commands
2420 `set/show sh calling-convention'.
2422 * GDB can now read compressed debug sections, as produced by GNU gold
2423 with the --compress-debug-sections=zlib flag.
2425 * 64-bit core files are now supported on AIX.
2427 * Thread switching is now supported on Tru64.
2429 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2430 which will be allocated using malloc later in program execution.
2432 * The qXfer:libraries:read remote procotol packet now allows passing a
2433 list of section offsets.
2435 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2436 conditions handling signals delivered during attach or thread creation
2437 have also been fixed.
2439 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2440 From the user's standpoint, all unqualified instances of True and False
2441 are treated as the standard definitions, regardless of context.
2443 * GDB now parses C++ symbol and type names more flexibly. For
2446 template<typename T> class C { };
2449 GDB will now correctly handle all of:
2451 ptype C<char const *>
2452 ptype C<char const*>
2453 ptype C<const char *>
2454 ptype C<const char*>
2456 * New features in the GDB remote stub, gdbserver
2458 - The "--wrapper" command-line argument tells gdbserver to use a
2459 wrapper program to launch programs for debugging.
2461 - On PowerPC and S/390 targets, it is now possible to use a single
2462 gdbserver executable to debug both 32-bit and 64-bit programs.
2463 (This requires gdbserver itself to be built as a 64-bit executable.)
2465 - gdbserver uses the new noack protocol mode for TCP connections to
2466 reduce communications latency, if also supported and enabled in GDB.
2468 - Support for the sparc64-linux-gnu target is now included in
2471 - The amd64-linux build of gdbserver now supports debugging both
2472 32-bit and 64-bit programs.
2474 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2475 now support hardware watchpoints, and will use them automatically
2480 GDB now has support for scripting using Python. Whether this is
2481 available is determined at configure time.
2483 New GDB commands can now be written in Python.
2485 * Ada tasking support
2487 Ada tasks can now be inspected in GDB. The following commands have
2491 Print the list of Ada tasks.
2493 Print detailed information about task number N.
2495 Print the task number of the current task.
2497 Switch the context of debugging to task number N.
2499 * Support for user-defined prefixed commands. The "define" command can
2500 add new commands to existing prefixes, e.g. "target".
2502 * Multi-inferior, multi-process debugging.
2504 GDB now has generalized support for multi-inferior debugging. See
2505 "Debugging Multiple Inferiors" in the manual for more information.
2506 Although availability still depends on target support, the command
2507 set is more uniform now. The GNU/Linux specific multi-forks support
2508 has been migrated to this new framework. This implied some user
2509 visible changes; see "New commands" and also "Removed commands"
2512 * Target descriptions can now describe the target OS ABI. See the
2513 "Target Description Format" section in the user manual for more
2516 * Target descriptions can now describe "compatible" architectures
2517 to indicate that the target can execute applications for a different
2518 architecture in addition to those for the main target architecture.
2519 See the "Target Description Format" section in the user manual for
2522 * Multi-architecture debugging.
2524 GDB now includes general supports for debugging applications on
2525 hybrid systems that use more than one single processor architecture
2526 at the same time. Each such hybrid architecture still requires
2527 specific support to be added. The only hybrid architecture supported
2528 in this version of GDB is the Cell Broadband Engine.
2530 * GDB now supports integrated debugging of Cell/B.E. applications that
2531 use both the PPU and SPU architectures. To enable support for hybrid
2532 Cell/B.E. debugging, you need to configure GDB to support both the
2533 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2534 --enable-targets configure option.
2536 * Non-stop mode debugging.
2538 For some targets, GDB now supports an optional mode of operation in
2539 which you can examine stopped threads while other threads continue
2540 to execute freely. This is referred to as non-stop mode, with the
2541 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2542 section in the user manual for more information.
2544 To be able to support remote non-stop debugging, a remote stub needs
2545 to implement the non-stop mode remote protocol extensions, as
2546 described in the "Remote Non-Stop" section of the user manual. The
2547 GDB remote stub, gdbserver, has been adjusted to support these
2548 extensions on linux targets.
2550 * New commands (for set/show, see "New options" below)
2552 catch syscall [NAME(S) | NUMBER(S)]
2553 Catch system calls. Arguments, which should be names of system
2554 calls or their numbers, mean catch only those syscalls. Without
2555 arguments, every syscall will be caught. When the inferior issues
2556 any of the specified syscalls, GDB will stop and announce the system
2557 call, both when it is called and when its call returns. This
2558 feature is currently available with a native GDB running on the
2559 Linux Kernel, under the following architectures: x86, x86_64,
2560 PowerPC and PowerPC64.
2562 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2564 Search memory for a sequence of bytes.
2566 maint set python print-stack
2567 maint show python print-stack
2568 Show a stack trace when an error is encountered in a Python script.
2571 Invoke CODE by passing it to the Python interpreter.
2576 These allow macros to be defined, undefined, and listed
2580 Show operating system information about processes.
2583 List the inferiors currently under GDB's control.
2586 Switch focus to inferior number NUM.
2589 Detach from inferior number NUM.
2592 Kill inferior number NUM.
2596 set spu stop-on-load
2597 show spu stop-on-load
2598 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2600 set spu auto-flush-cache
2601 show spu auto-flush-cache
2602 Control whether to automatically flush the software-managed cache
2603 during Cell/B.E. debugging.
2605 set sh calling-convention
2606 show sh calling-convention
2607 Control the calling convention used when calling SH target functions.
2610 show debug timestamp
2611 Control display of timestamps with GDB debugging output.
2613 set disassemble-next-line
2614 show disassemble-next-line
2615 Control display of disassembled source lines or instructions when
2618 set remote noack-packet
2619 show remote noack-packet
2620 Set/show the use of remote protocol QStartNoAckMode packet. See above
2621 under "New remote packets."
2623 set remote query-attached-packet
2624 show remote query-attached-packet
2625 Control use of remote protocol `qAttached' (query-attached) packet.
2627 set remote read-siginfo-object
2628 show remote read-siginfo-object
2629 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2632 set remote write-siginfo-object
2633 show remote write-siginfo-object
2634 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2637 set remote reverse-continue
2638 show remote reverse-continue
2639 Control use of remote protocol 'bc' (reverse-continue) packet.
2641 set remote reverse-step
2642 show remote reverse-step
2643 Control use of remote protocol 'bs' (reverse-step) packet.
2645 set displaced-stepping
2646 show displaced-stepping
2647 Control displaced stepping mode. Displaced stepping is a way to
2648 single-step over breakpoints without removing them from the debuggee.
2649 Also known as "out-of-line single-stepping".
2652 show debug displaced
2653 Control display of debugging info for displaced stepping.
2655 maint set internal-error
2656 maint show internal-error
2657 Control what GDB does when an internal error is detected.
2659 maint set internal-warning
2660 maint show internal-warning
2661 Control what GDB does when an internal warning is detected.
2666 Use a wrapper program to launch programs for debugging.
2668 set multiple-symbols (all|ask|cancel)
2669 show multiple-symbols
2670 The value of this variable can be changed to adjust the debugger behavior
2671 when an expression or a breakpoint location contains an ambiguous symbol
2672 name (an overloaded function name, for instance).
2674 set breakpoint always-inserted
2675 show breakpoint always-inserted
2676 Keep breakpoints always inserted in the target, as opposed to inserting
2677 them when resuming the target, and removing them when the target stops.
2678 This option can improve debugger performance on slow remote targets.
2680 set arm fallback-mode (arm|thumb|auto)
2681 show arm fallback-mode
2682 set arm force-mode (arm|thumb|auto)
2684 These commands control how ARM GDB determines whether instructions
2685 are ARM or Thumb. The default for both settings is auto, which uses
2686 the current CPSR value for instructions without symbols; previous
2687 versions of GDB behaved as if "set arm fallback-mode arm".
2689 set disable-randomization
2690 show disable-randomization
2691 Standalone programs run with the virtual address space randomization enabled
2692 by default on some platforms. This option keeps the addresses stable across
2693 multiple debugging sessions.
2697 Control whether other threads are stopped or not when some thread hits
2702 Requests that asynchronous execution is enabled in the target, if available.
2703 In this case, it's possible to resume target in the background, and interact
2704 with GDB while the target is running. "show target-async" displays the
2705 current state of asynchronous execution of the target.
2707 set target-wide-charset
2708 show target-wide-charset
2709 The target-wide-charset is the name of the character set that GDB
2710 uses when printing characters whose type is wchar_t.
2712 set tcp auto-retry (on|off)
2714 set tcp connect-timeout
2715 show tcp connect-timeout
2716 These commands allow GDB to retry failed TCP connections to a remote stub
2717 with a specified timeout period; this is useful if the stub is launched
2718 in parallel with GDB but may not be ready to accept connections immediately.
2720 set libthread-db-search-path
2721 show libthread-db-search-path
2722 Control list of directories which GDB will search for appropriate
2725 set schedule-multiple (on|off)
2726 show schedule-multiple
2727 Allow GDB to resume all threads of all processes or only threads of
2728 the current process.
2732 Use more aggressive caching for accesses to the stack. This improves
2733 performance of remote debugging (particularly backtraces) without
2734 affecting correctness.
2736 set interactive-mode (on|off|auto)
2737 show interactive-mode
2738 Control whether GDB runs in interactive mode (on) or not (off).
2739 When in interactive mode, GDB waits for the user to answer all
2740 queries. Otherwise, GDB does not wait and assumes the default
2741 answer. When set to auto (the default), GDB determines which
2742 mode to use based on the stdin settings.
2747 For program forks, this is replaced by the new more generic `info
2748 inferiors' command. To list checkpoints, you can still use the
2749 `info checkpoints' command, which was an alias for the `info forks'
2753 Replaced by the new `inferior' command. To switch between
2754 checkpoints, you can still use the `restart' command, which was an
2755 alias for the `fork' command.
2758 This is removed, since some targets don't have a notion of
2759 processes. To switch between processes, you can still use the
2760 `inferior' command using GDB's own inferior number.
2763 For program forks, this is replaced by the new more generic `kill
2764 inferior' command. To delete a checkpoint, you can still use the
2765 `delete checkpoint' command, which was an alias for the `delete
2769 For program forks, this is replaced by the new more generic `detach
2770 inferior' command. To detach a checkpoint, you can still use the
2771 `detach checkpoint' command, which was an alias for the `detach
2774 * New native configurations
2776 x86/x86_64 Darwin i[34567]86-*-darwin*
2778 x86_64 MinGW x86_64-*-mingw*
2782 Lattice Mico32 lm32-*
2783 x86 DICOS i[34567]86-*-dicos*
2784 x86_64 DICOS x86_64-*-dicos*
2787 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2788 (mingw32ce) debugging.
2794 These commands were actually not implemented on any target.
2796 *** Changes in GDB 6.8
2798 * New native configurations
2800 NetBSD/hppa hppa*-*netbsd*
2801 Xtensa GNU/Linux xtensa*-*-linux*
2805 NetBSD/hppa hppa*-*-netbsd*
2806 Xtensa GNU/Lunux xtensa*-*-linux*
2808 * Change in command line behavior -- corefiles vs. process ids.
2810 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2811 attaching to process NUMBER fails, GDB no longer attempts to open a
2812 core file named NUMBER. Attaching to a program using the -c option
2813 is no longer supported. Instead, use the '-p' or '--pid' options.
2815 * GDB can now be built as a native debugger for debugging Windows x86
2816 (mingw32) Portable Executable (PE) programs.
2818 * Pending breakpoints no longer change their number when their address
2821 * GDB now supports breakpoints with multiple locations,
2822 including breakpoints on C++ constructors, inside C++ templates,
2823 and in inlined functions.
2825 * GDB's ability to debug optimized code has been improved. GDB more
2826 accurately identifies function bodies and lexical blocks that occupy
2827 more than one contiguous range of addresses.
2829 * Target descriptions can now describe registers for PowerPC.
2831 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2832 registers on PowerPC targets.
2834 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2835 targets even when the libthread_db library is not available.
2837 * The GDB remote stub, gdbserver, now supports the new file transfer
2838 commands (remote put, remote get, and remote delete).
2840 * The GDB remote stub, gdbserver, now supports run and attach in
2841 extended-remote mode.
2843 * hppa*64*-*-hpux11* target broken
2844 The debugger is unable to start a program and fails with the following
2845 error: "Error trying to get information about dynamic linker".
2846 The gdb-6.7 release is also affected.
2848 * GDB now supports the --enable-targets= configure option to allow
2849 building a single GDB executable that supports multiple remote
2850 target architectures.
2852 * GDB now supports debugging C and C++ programs which use the
2853 Decimal Floating Point extension. In addition, the PowerPC target
2854 now has a set of pseudo-registers to inspect decimal float values
2855 stored in two consecutive float registers.
2857 * The -break-insert MI command can optionally create pending
2860 * Improved support for debugging Ada
2861 Many improvements to the Ada language support have been made. These
2863 - Better support for Ada2005 interface types
2864 - Improved handling of arrays and slices in general
2865 - Better support for Taft-amendment types
2866 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2868 - Improved command completion in Ada
2871 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2876 set print frame-arguments (all|scalars|none)
2877 show print frame-arguments
2878 The value of this variable can be changed to control which argument
2879 values should be printed by the debugger when displaying a frame.
2884 Transfer files to and from a remote target, and delete remote files.
2891 Transfer files to and from a remote target, and delete remote files.
2893 * New remote packets
2900 Open, close, read, write, and delete files on the remote system.
2903 Attach to an existing process on the remote system, in extended-remote
2907 Run a new process on the remote system, in extended-remote mode.
2909 *** Changes in GDB 6.7
2911 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2912 bfd, libiberty and opcodes, as revealed by static analysis donated by
2913 Coverity, Inc. (http://scan.coverity.com).
2915 * When looking up multiply-defined global symbols, GDB will now prefer the
2916 symbol definition in the current shared library if it was built using the
2917 -Bsymbolic linker option.
2919 * When the Text User Interface (TUI) is not configured, GDB will now
2920 recognize the -tui command-line option and print a message that the TUI
2923 * The GDB remote stub, gdbserver, now has lower overhead for high
2924 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2926 * GDB for MIPS targets now autodetects whether a remote target provides
2927 32-bit or 64-bit register values.
2929 * Support for C++ member pointers has been improved.
2931 * GDB now understands XML target descriptions, which specify the
2932 target's overall architecture. GDB can read a description from
2933 a local file or over the remote serial protocol.
2935 * Vectors of single-byte data use a new integer type which is not
2936 automatically displayed as character or string data.
2938 * The /s format now works with the print command. It displays
2939 arrays of single-byte integers and pointers to single-byte integers
2942 * Target descriptions can now describe target-specific registers,
2943 for architectures which have implemented the support (currently
2944 only ARM, M68K, and MIPS).
2946 * GDB and the GDB remote stub, gdbserver, now support the XScale
2949 * The GDB remote stub, gdbserver, has been updated to support
2950 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2951 has been rewritten to use the standard GDB remote protocol.
2953 * GDB can now step into C++ functions which are called through thunks.
2955 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2957 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2958 layout. It also supports a TextSeg= and DataSeg= response when only
2959 segment base addresses (rather than offsets) are available.
2961 * The /i format now outputs any trailing branch delay slot instructions
2962 immediately following the last instruction within the count specified.
2964 * The GDB remote protocol "T" stop reply packet now supports a
2965 "library" response. Combined with the new "qXfer:libraries:read"
2966 packet, this response allows GDB to debug shared libraries on targets
2967 where the operating system manages the list of loaded libraries (e.g.
2968 Windows and SymbianOS).
2970 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2971 (DLLs) on Windows and Windows CE targets.
2973 * GDB now supports a faster verification that a .debug file matches its binary
2974 according to its build-id signature, if the signature is present.
2980 Enable or disable hardware flow control (RTS/CTS) on the serial port
2981 when debugging using remote targets.
2983 set mem inaccessible-by-default
2984 show mem inaccessible-by-default
2985 If the target supplies a memory map, for instance via the remote
2986 protocol's "qXfer:memory-map:read" packet, setting this variable
2987 prevents GDB from accessing memory outside the memory map. This
2988 is useful for targets with memory mapped registers or which react
2989 badly to accesses of unmapped address space.
2991 set breakpoint auto-hw
2992 show breakpoint auto-hw
2993 If the target supplies a memory map, for instance via the remote
2994 protocol's "qXfer:memory-map:read" packet, setting this variable
2995 lets GDB use hardware breakpoints automatically for memory regions
2996 where it can not use software breakpoints. This covers both the
2997 "break" command and internal breakpoints used for other commands
2998 including "next" and "finish".
3001 catch exception unhandled
3002 Stop the program execution when Ada exceptions are raised.
3005 Stop the program execution when an Ada assertion failed.
3009 Set an alternate system root for target files. This is a more
3010 general version of "set solib-absolute-prefix", which is now
3011 an alias to "set sysroot".
3014 Provide extended SPU facility status information. This set of
3015 commands is available only when debugging the Cell/B.E. SPU
3018 * New native configurations
3020 OpenBSD/sh sh*-*openbsd*
3023 unset tdesc filename
3025 Use the specified local file as an XML target description, and do
3026 not query the target for its built-in description.
3030 OpenBSD/sh sh*-*-openbsd*
3031 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3032 Toshiba Media Processor mep-elf
3034 * New remote packets
3037 Ignore the specified signals; pass them directly to the debugged program
3038 without stopping other threads or reporting them to GDB.
3040 qXfer:features:read:
3041 Read an XML target description from the target, which describes its
3046 Read or write contents of an spufs file on the target system. These
3047 packets are available only on the Cell/B.E. SPU architecture.
3049 qXfer:libraries:read:
3050 Report the loaded shared libraries. Combined with new "T" packet
3051 response, this packet allows GDB to debug shared libraries on
3052 targets where the operating system manages the list of loaded
3053 libraries (e.g. Windows and SymbianOS).
3057 Support for these obsolete configurations has been removed.
3065 i[34567]86-*-lynxos*
3066 i[34567]86-*-netware*
3067 i[34567]86-*-sco3.2v5*
3068 i[34567]86-*-sco3.2v4*
3070 i[34567]86-*-sysv4.2*
3073 i[34567]86-*-unixware2*
3074 i[34567]86-*-unixware*
3083 * Other removed features
3090 Various m68k-only ROM monitors.
3097 Various Renesas ROM monitors and debugging interfaces for SH and
3102 Support for a Macraigor serial interface to on-chip debugging.
3103 GDB does not directly support the newer parallel or USB
3108 A debug information format. The predecessor to DWARF 2 and
3109 DWARF 3, which are still supported.
3111 Support for the HP aCC compiler on HP-UX/PA-RISC
3113 SOM-encapsulated symbolic debugging information, automatic
3114 invocation of pxdb, and the aCC custom C++ ABI. This does not
3115 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3116 with aCC can still be debugged on an assembly level.
3118 MIPS ".pdr" sections
3120 A MIPS-specific format used to describe stack frame layout
3121 in debugging information.
3125 GDB could work with an older version of Guile to debug
3126 the interpreter and Scheme programs running in it.
3128 set mips stack-arg-size
3129 set mips saved-gpreg-size
3131 Use "set mips abi" to control parameter passing for MIPS.
3133 *** Changes in GDB 6.6
3138 Cell Broadband Engine SPU spu-elf
3140 * GDB can now be configured as a cross-debugger targeting native Windows
3141 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3142 running on a Windows system over TCP/IP to debug Windows programs.
3144 * The GDB remote stub, gdbserver, has been updated to support Windows and
3145 Cygwin debugging. Both single-threaded and multi-threaded programs are
3148 * The "set trust-readonly-sections" command works again. This command was
3149 broken in GDB 6.3, 6.4, and 6.5.
3151 * The "load" command now supports writing to flash memory, if the remote
3152 stub provides the required support.
3154 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3155 longer requires symbolic debug information (e.g. DWARF-2).
3160 unset substitute-path
3161 show substitute-path
3162 Manage a list of substitution rules that GDB uses to rewrite the name
3163 of the directories where the sources are located. This can be useful
3164 for instance when the sources were moved to a different location
3165 between compilation and debugging.
3169 Print each CLI command as it is executed. Each command is prefixed with
3170 a number of `+' symbols representing the nesting depth.
3171 The source command now has a `-v' option to enable the same feature.
3175 The ARM Demon monitor support (RDP protocol, "target rdp").
3177 Kernel Object Display, an embedded debugging feature which only worked with
3178 an obsolete version of Cisco IOS.
3180 The 'set download-write-size' and 'show download-write-size' commands.
3182 * New remote packets
3185 Tell a stub about GDB client features, and request remote target features.
3186 The first feature implemented is PacketSize, which allows the target to
3187 specify the size of packets it can handle - to minimize the number of
3188 packets required and improve performance when connected to a remote
3192 Fetch an OS auxilliary vector from the remote stub. This packet is a
3193 more efficient replacement for qPart:auxv:read.
3195 qXfer:memory-map:read:
3196 Fetch a memory map from the remote stub, including information about
3197 RAM, ROM, and flash memory devices.
3202 Erase and program a flash memory device.
3204 * Removed remote packets
3207 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3208 used it, and only gdbserver implemented it.
3210 *** Changes in GDB 6.5
3214 Renesas M32C/M16C m32c-elf
3216 Morpho Technologies ms1 ms1-elf
3220 init-if-undefined Initialize a convenience variable, but
3221 only if it doesn't already have a value.
3223 The following commands are presently only implemented for native GNU/Linux:
3225 checkpoint Save a snapshot of the program state.
3227 restart <n> Return the program state to a
3228 previously saved state.
3230 info checkpoints List currently saved checkpoints.
3232 delete-checkpoint <n> Delete a previously saved checkpoint.
3234 set|show detach-on-fork Tell gdb whether to detach from a newly
3235 forked process, or to keep debugging it.
3237 info forks List forks of the user program that
3238 are available to be debugged.
3240 fork <n> Switch to debugging one of several
3241 forks of the user program that are
3242 available to be debugged.
3244 delete-fork <n> Delete a fork from the list of forks
3245 that are available to be debugged (and
3246 kill the forked process).
3248 detach-fork <n> Delete a fork from the list of forks
3249 that are available to be debugged (and
3250 allow the process to continue).
3254 Morpho Technologies ms2 ms1-elf
3256 * Improved Windows host support
3258 GDB now builds as a cross debugger hosted on i686-mingw32, including
3259 native console support, and remote communications using either
3260 network sockets or serial ports.
3262 * Improved Modula-2 language support
3264 GDB can now print most types in the Modula-2 syntax. This includes:
3265 basic types, set types, record types, enumerated types, range types,
3266 pointer types and ARRAY types. Procedure var parameters are correctly
3267 printed and hexadecimal addresses and character constants are also
3268 written in the Modula-2 syntax. Best results can be obtained by using
3269 GNU Modula-2 together with the -gdwarf-2 command line option.
3273 The ARM rdi-share module.
3275 The Netware NLM debug server.
3277 *** Changes in GDB 6.4
3279 * New native configurations
3281 OpenBSD/arm arm*-*-openbsd*
3282 OpenBSD/mips64 mips64-*-openbsd*
3286 Morpho Technologies ms1 ms1-elf
3288 * New command line options
3290 --batch-silent As for --batch, but totally silent.
3291 --return-child-result The debugger will exist with the same value
3292 the child (debugged) program exited with.
3293 --eval-command COMMAND, -ex COMMAND
3294 Execute a single GDB CLI command. This may be
3295 specified multiple times and in conjunction
3296 with the --command (-x) option.
3298 * Deprecated commands removed
3300 The following commands, that were deprecated in 2000, have been
3304 set|show arm disassembly-flavor set|show arm disassembler
3305 othernames set arm disassembler
3306 set|show remotedebug set|show debug remote
3307 set|show archdebug set|show debug arch
3308 set|show eventdebug set|show debug event
3311 * New BSD user-level threads support
3313 It is now possible to debug programs using the user-level threads
3314 library on OpenBSD and FreeBSD. Currently supported (target)
3317 FreeBSD/amd64 x86_64-*-freebsd*
3318 FreeBSD/i386 i386-*-freebsd*
3319 OpenBSD/i386 i386-*-openbsd*
3321 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3322 are not yet supported.
3324 * New support for Matsushita MN10300 w/sim added
3325 (Work in progress). mn10300-elf.
3327 * REMOVED configurations and files
3329 VxWorks and the XDR protocol *-*-vxworks
3330 Motorola MCORE mcore-*-*
3331 National Semiconductor NS32000 ns32k-*-*
3333 * New "set print array-indexes" command
3335 After turning this setting "on", GDB prints the index of each element
3336 when displaying arrays. The default is "off" to preserve the previous
3339 * VAX floating point support
3341 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3343 * User-defined command support
3345 In addition to using $arg0..$arg9 for argument passing, it is now possible
3346 to use $argc to determine now many arguments have been passed. See the
3347 section on user-defined commands in the user manual for more information.
3349 *** Changes in GDB 6.3:
3351 * New command line option
3353 GDB now accepts -l followed by a number to set the timeout for remote
3356 * GDB works with GCC -feliminate-dwarf2-dups
3358 GDB now supports a more compact representation of DWARF-2 debug
3359 information using DW_FORM_ref_addr references. These are produced
3360 by GCC with the option -feliminate-dwarf2-dups and also by some
3361 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3362 to use -feliminate-dwarf2-dups.
3364 * Internationalization
3366 When supported by the host system, GDB will be built with
3367 internationalization (libintl). The task of marking up the sources is
3368 continued, we're looking forward to our first translation.
3372 Initial support for debugging programs compiled with the GNAT
3373 implementation of the Ada programming language has been integrated
3374 into GDB. In this release, support is limited to expression evaluation.
3376 * New native configurations
3378 GNU/Linux/m32r m32r-*-linux-gnu
3382 GDB's remote protocol now includes support for the 'p' packet. This
3383 packet is used to fetch individual registers from a remote inferior.
3385 * END-OF-LIFE registers[] compatibility module
3387 GDB's internal register infrastructure has been completely rewritten.
3388 The new infrastructure making possible the implementation of key new
3389 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3392 GDB 6.3 will be the last release to include the the registers[]
3393 compatibility module that allowed out-of-date configurations to
3394 continue to work. This change directly impacts the following
3404 powerpc bdm protocol
3406 Unless there is activity to revive these configurations, they will be
3407 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3409 * OBSOLETE configurations and files
3411 Configurations that have been declared obsolete in this release have
3412 been commented out. Unless there is activity to revive these
3413 configurations, the next release of GDB will have their sources
3414 permanently REMOVED.
3423 *** Changes in GDB 6.2.1:
3425 * MIPS `break main; run' gave an heuristic-fence-post warning
3427 When attempting to run even a simple program, a warning about
3428 heuristic-fence-post being hit would be reported. This problem has
3431 * MIPS IRIX 'long double' crashed GDB
3433 When examining a long double variable, GDB would get a segmentation
3434 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3435 IRIX long double values).
3439 A bug in the VAX stack code was causing problems with the "next"
3440 command. This problem has been fixed.
3442 *** Changes in GDB 6.2:
3444 * Fix for ``many threads''
3446 On GNU/Linux systems that use the NPTL threads library, a program
3447 rapidly creating and deleting threads would confuse GDB leading to the
3450 ptrace: No such process.
3451 thread_db_get_info: cannot get thread info: generic error
3453 This problem has been fixed.
3455 * "-async" and "-noasync" options removed.
3457 Support for the broken "-noasync" option has been removed (it caused
3460 * New ``start'' command.
3462 This command runs the program until the begining of the main procedure.
3464 * New BSD Kernel Data Access Library (libkvm) interface
3466 Using ``target kvm'' it is now possible to debug kernel core dumps and
3467 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3468 platforms. Currently supported (native-only) configurations are:
3470 FreeBSD/amd64 x86_64-*-freebsd*
3471 FreeBSD/i386 i?86-*-freebsd*
3472 NetBSD/i386 i?86-*-netbsd*
3473 NetBSD/m68k m68*-*-netbsd*
3474 NetBSD/sparc sparc-*-netbsd*
3475 OpenBSD/amd64 x86_64-*-openbsd*
3476 OpenBSD/i386 i?86-*-openbsd*
3477 OpenBSD/m68k m68*-openbsd*
3478 OpenBSD/sparc sparc-*-openbsd*
3480 * Signal trampoline code overhauled
3482 Many generic problems with GDB's signal handling code have been fixed.
3483 These include: backtraces through non-contiguous stacks; recognition
3484 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3485 call; backtrace through a signal trampoline; step into and out of
3486 signal handlers; and single-stepping in the signal trampoline.
3488 Please note that kernel bugs are a limiting factor here. These
3489 features have been shown to work on an s390 GNU/Linux system that
3490 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3492 * Cygwin support for DWARF 2 added.
3494 * New native configurations
3496 GNU/Linux/hppa hppa*-*-linux*
3497 OpenBSD/hppa hppa*-*-openbsd*
3498 OpenBSD/m68k m68*-*-openbsd*
3499 OpenBSD/m88k m88*-*-openbsd*
3500 OpenBSD/powerpc powerpc-*-openbsd*
3501 NetBSD/vax vax-*-netbsd*
3502 OpenBSD/vax vax-*-openbsd*
3504 * END-OF-LIFE frame compatibility module
3506 GDB's internal frame infrastructure has been completely rewritten.
3507 The new infrastructure making it possible to support key new features
3508 including DWARF 2 Call Frame Information. To aid in the task of
3509 migrating old configurations to this new infrastructure, a
3510 compatibility module, that allowed old configurations to continue to
3511 work, was also included.
3513 GDB 6.2 will be the last release to include this frame compatibility
3514 module. This change directly impacts the following configurations:
3524 Unless there is activity to revive these configurations, they will be
3525 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3527 * REMOVED configurations and files
3529 Sun 3, running SunOS 3 m68*-*-sunos3*
3530 Sun 3, running SunOS 4 m68*-*-sunos4*
3531 Sun 2, running SunOS 3 m68000-*-sunos3*
3532 Sun 2, running SunOS 4 m68000-*-sunos4*
3533 Motorola 680x0 running LynxOS m68*-*-lynxos*
3534 AT&T 3b1/Unix pc m68*-att-*
3535 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3536 decstation mips-dec-* mips-little-*
3537 riscos mips-*-riscos* mips-*-sysv*
3538 sonymips mips-sony-*
3539 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3541 *** Changes in GDB 6.1.1:
3543 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3545 The TUI (Text-mode User Interface) is now built as part of a default
3546 GDB configuration. It is enabled by either selecting the TUI with the
3547 command line option "-i=tui" or by running the separate "gdbtui"
3548 program. For more information on the TUI, see the manual "Debugging
3551 * Pending breakpoint support (also included in GDB 6.1)
3553 Support has been added to allow you to specify breakpoints in shared
3554 libraries that have not yet been loaded. If a breakpoint location
3555 cannot be found, and the "breakpoint pending" option is set to auto,
3556 GDB queries you if you wish to make the breakpoint pending on a future
3557 shared-library load. If and when GDB resolves the breakpoint symbol,
3558 the pending breakpoint is removed as one or more regular breakpoints
3561 Pending breakpoints are very useful for GCJ Java debugging.
3563 * Fixed ISO-C build problems
3565 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3566 non ISO-C code that stopped them being built using a more strict ISO-C
3567 compiler (e.g., IBM's C compiler).
3569 * Fixed build problem on IRIX 5
3571 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3572 wasn't able to compile compile on an IRIX 5 system.
3574 * Added execute permission to gdb/gdbserver/configure
3576 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3577 permission. This bug would cause configure to fail on a number of
3578 systems (Solaris, IRIX). Ref: server/519.
3580 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3582 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3583 has been updated to use constant array sizes.
3585 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3587 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3588 its generated DWARF Call Frame Info. This encoding was causing GDB to
3589 panic, that panic has been fixed. Ref: gdb/1628.
3591 * Fixed a problem when examining parameters in shared library code.
3593 When examining parameters in optimized shared library code generated
3594 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3595 not available''. GDB now correctly displays the variable's value.
3597 *** Changes in GDB 6.1:
3599 * Removed --with-mmalloc
3601 Support for the mmalloc memory manager has been removed, as it
3602 conflicted with the internal gdb byte cache.
3604 * Changes in AMD64 configurations
3606 The AMD64 target now includes the %cs and %ss registers. As a result
3607 the AMD64 remote protocol has changed; this affects the floating-point
3608 and SSE registers. If you rely on those registers for your debugging,
3609 you should upgrade gdbserver on the remote side.
3611 * Revised SPARC target
3613 The SPARC target has been completely revised, incorporating the
3614 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3615 support for LynxOS and SunOS 4 has been dropped. Calling functions
3616 from within GDB on operating systems with a non-executable stack
3617 (Solaris, OpenBSD) now works.
3621 GDB has a new C++ demangler which does a better job on the mangled
3622 names generated by current versions of g++. It also runs faster, so
3623 with this and other changes gdb should now start faster on large C++
3626 * DWARF 2 Location Expressions
3628 GDB support for location expressions has been extended to support function
3629 arguments and frame bases. Older versions of GDB could crash when they
3632 * C++ nested types and namespaces
3634 GDB's support for nested types and namespaces in C++ has been
3635 improved, especially if you use the DWARF 2 debugging format. (This
3636 is the default for recent versions of GCC on most platforms.)
3637 Specifically, if you have a class "Inner" defined within a class or
3638 namespace "Outer", then GDB realizes that the class's name is
3639 "Outer::Inner", not simply "Inner". This should greatly reduce the
3640 frequency of complaints about not finding RTTI symbols. In addition,
3641 if you are stopped at inside of a function defined within a namespace,
3642 GDB modifies its name lookup accordingly.
3644 * New native configurations
3646 NetBSD/amd64 x86_64-*-netbsd*
3647 OpenBSD/amd64 x86_64-*-openbsd*
3648 OpenBSD/alpha alpha*-*-openbsd*
3649 OpenBSD/sparc sparc-*-openbsd*
3650 OpenBSD/sparc64 sparc64-*-openbsd*
3652 * New debugging protocols
3654 M32R with SDI protocol m32r-*-elf*
3656 * "set prompt-escape-char" command deleted.
3658 The command "set prompt-escape-char" has been deleted. This command,
3659 and its very obscure effet on GDB's prompt, was never documented,
3660 tested, nor mentioned in the NEWS file.
3662 * OBSOLETE configurations and files
3664 Configurations that have been declared obsolete in this release have
3665 been commented out. Unless there is activity to revive these
3666 configurations, the next release of GDB will have their sources
3667 permanently REMOVED.
3669 Sun 3, running SunOS 3 m68*-*-sunos3*
3670 Sun 3, running SunOS 4 m68*-*-sunos4*
3671 Sun 2, running SunOS 3 m68000-*-sunos3*
3672 Sun 2, running SunOS 4 m68000-*-sunos4*
3673 Motorola 680x0 running LynxOS m68*-*-lynxos*
3674 AT&T 3b1/Unix pc m68*-att-*
3675 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3676 decstation mips-dec-* mips-little-*
3677 riscos mips-*-riscos* mips-*-sysv*
3678 sonymips mips-sony-*
3679 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3681 * REMOVED configurations and files
3683 SGI Irix-4.x mips-sgi-irix4 or iris4
3684 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3685 Z8000 simulator z8k-zilog-none or z8ksim
3686 Matsushita MN10200 w/simulator mn10200-*-*
3687 H8/500 simulator h8500-hitachi-hms or h8500hms
3688 HP/PA running BSD hppa*-*-bsd*
3689 HP/PA running OSF/1 hppa*-*-osf*
3690 HP/PA Pro target hppa*-*-pro*
3691 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3692 386BSD i[3456]86-*-bsd*
3693 Sequent family i[3456]86-sequent-sysv4*
3694 i[3456]86-sequent-sysv*
3695 i[3456]86-sequent-bsd*
3696 SPARC running LynxOS sparc-*-lynxos*
3697 SPARC running SunOS 4 sparc-*-sunos4*
3698 Tsqware Sparclet sparclet-*-*
3699 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3701 *** Changes in GDB 6.0:
3705 Support for debugging the Objective-C programming language has been
3706 integrated into GDB.
3708 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3710 DWARF 2's Call Frame Information makes available compiler generated
3711 information that more exactly describes the program's run-time stack.
3712 By using this information, GDB is able to provide more robust stack
3715 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3716 have been updated to use a new backtrace mechanism which includes
3717 DWARF 2 CFI support.
3721 GDB's remote protocol has been extended to include support for hosted
3722 file I/O (where the remote target uses GDB's file system). See GDB's
3723 remote protocol documentation for details.
3725 * All targets using the new architecture framework.
3727 All of GDB's targets have been updated to use the new internal
3728 architecture framework. The way is now open for future GDB releases
3729 to include cross-architecture native debugging support (i386 on amd64,
3732 * GNU/Linux's Thread Local Storage (TLS)
3734 GDB now includes support for for the GNU/Linux implementation of
3735 per-thread variables.
3737 * GNU/Linux's Native POSIX Thread Library (NPTL)
3739 GDB's thread code has been updated to work with either the new
3740 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3742 * Separate debug info.
3744 GDB, in conjunction with BINUTILS, now supports a mechanism for
3745 automatically loading debug information from a separate file. Instead
3746 of shipping full debug and non-debug versions of system libraries,
3747 system integrators can now instead ship just the stripped libraries
3748 and optional debug files.
3750 * DWARF 2 Location Expressions
3752 DWARF 2 Location Expressions allow the compiler to more completely
3753 describe the location of variables (even in optimized code) to the
3756 GDB now includes preliminary support for location expressions (support
3757 for DW_OP_piece is still missing).
3761 A number of long standing bugs that caused GDB to die while starting a
3762 Java application have been fixed. GDB's Java support is now
3763 considered "useable".
3765 * GNU/Linux support for fork, vfork, and exec.
3767 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3768 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3771 * GDB supports logging output to a file
3773 There are two new commands, "set logging" and "show logging", which can be
3774 used to capture GDB's output to a file.
3776 * The meaning of "detach" has changed for gdbserver
3778 The "detach" command will now resume the application, as documented. To
3779 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3782 * d10v, m68hc11 `regs' command deprecated
3784 The `info registers' command has been updated so that it displays the
3785 registers using a format identical to the old `regs' command.
3789 A new command, "maint set profile on/off", has been added. This command can
3790 be used to enable or disable profiling while running GDB, to profile a
3791 session or a set of commands. In addition there is a new configure switch,
3792 "--enable-profiling", which will cause GDB to be compiled with profiling
3793 data, for more informative profiling results.
3795 * Default MI syntax changed to "mi2".
3797 The default MI (machine interface) syntax, enabled by the command line
3798 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3799 "mi1", can be enabled by specifying the option "-i=mi1".
3801 Support for the original "mi0" syntax (included in GDB 5.0) has been
3804 Fix for gdb/192: removed extraneous space when displaying frame level.
3805 Fix for gdb/672: update changelist is now output in mi list format.
3806 Fix for gdb/702: a -var-assign that updates the value now shows up
3807 in a subsequent -var-update.
3809 * New native configurations.
3811 FreeBSD/amd64 x86_64-*-freebsd*
3813 * Multi-arched targets.
3815 HP/PA HPUX11 hppa*-*-hpux*
3816 Renesas M32R/D w/simulator m32r-*-elf*
3818 * OBSOLETE configurations and files
3820 Configurations that have been declared obsolete in this release have
3821 been commented out. Unless there is activity to revive these
3822 configurations, the next release of GDB will have their sources
3823 permanently REMOVED.
3825 Z8000 simulator z8k-zilog-none or z8ksim
3826 Matsushita MN10200 w/simulator mn10200-*-*
3827 H8/500 simulator h8500-hitachi-hms or h8500hms
3828 HP/PA running BSD hppa*-*-bsd*
3829 HP/PA running OSF/1 hppa*-*-osf*
3830 HP/PA Pro target hppa*-*-pro*
3831 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3832 Sequent family i[3456]86-sequent-sysv4*
3833 i[3456]86-sequent-sysv*
3834 i[3456]86-sequent-bsd*
3835 Tsqware Sparclet sparclet-*-*
3836 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3838 * REMOVED configurations and files
3841 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3842 IBM AIX PS/2 i[3456]86-*-aix
3843 i386 running Mach 3.0 i[3456]86-*-mach3*
3844 i386 running Mach i[3456]86-*-mach*
3845 i386 running OSF/1 i[3456]86-*osf1mk*
3846 HP/Apollo 68k Family m68*-apollo*-sysv*,
3848 m68*-hp-bsd*, m68*-hp-hpux*
3849 Argonaut Risc Chip (ARC) arc-*-*
3850 Mitsubishi D30V d30v-*-*
3851 Fujitsu FR30 fr30-*-elf*
3852 OS/9000 i[34]86-*-os9k
3853 I960 with MON960 i960-*-coff
3855 * MIPS $fp behavior changed
3857 The convenience variable $fp, for the MIPS, now consistently returns
3858 the address of the current frame's base. Previously, depending on the
3859 context, $fp could refer to either $sp or the current frame's base
3860 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3861 The GNU Source-Level Debugger''.
3863 *** Changes in GDB 5.3:
3865 * GNU/Linux shared library multi-threaded performance improved.
3867 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3868 `/proc', in preference to `ptrace' for memory reads. This may result
3869 in an improvement in the start-up time of multi-threaded, shared
3870 library applications when run under GDB. One GDB user writes: ``loads
3871 shared libs like mad''.
3873 * ``gdbserver'' now supports multi-threaded applications on some targets
3875 Support for debugging multi-threaded applications which use
3876 the GNU/Linux LinuxThreads package has been added for
3877 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3878 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3880 * GDB now supports C/C++ preprocessor macros.
3882 GDB now expands preprocessor macro invocations in C/C++ expressions,
3883 and provides various commands for showing macro definitions and how
3886 The new command `macro expand EXPRESSION' expands any macro
3887 invocations in expression, and shows the result.
3889 The new command `show macro MACRO-NAME' shows the definition of the
3890 macro named MACRO-NAME, and where it was defined.
3892 Most compilers don't include information about macros in the debugging
3893 information by default. In GCC 3.1, for example, you need to compile
3894 your program with the options `-gdwarf-2 -g3'. If the macro
3895 information is present in the executable, GDB will read it.
3897 * Multi-arched targets.
3899 DEC Alpha (partial) alpha*-*-*
3900 DEC VAX (partial) vax-*-*
3902 National Semiconductor NS32000 (partial) ns32k-*-*
3903 Motorola 68000 (partial) m68k-*-*
3904 Motorola MCORE mcore-*-*
3908 Fujitsu FRV architecture added by Red Hat frv*-*-*
3911 * New native configurations
3913 Alpha NetBSD alpha*-*-netbsd*
3914 SH NetBSD sh*-*-netbsdelf*
3915 MIPS NetBSD mips*-*-netbsd*
3916 UltraSPARC NetBSD sparc64-*-netbsd*
3918 * OBSOLETE configurations and files
3920 Configurations that have been declared obsolete in this release have
3921 been commented out. Unless there is activity to revive these
3922 configurations, the next release of GDB will have their sources
3923 permanently REMOVED.
3925 Mitsubishi D30V d30v-*-*
3926 OS/9000 i[34]86-*-os9k
3927 IBM AIX PS/2 i[3456]86-*-aix
3928 Fujitsu FR30 fr30-*-elf*
3929 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3930 Argonaut Risc Chip (ARC) arc-*-*
3931 i386 running Mach 3.0 i[3456]86-*-mach3*
3932 i386 running Mach i[3456]86-*-mach*
3933 i386 running OSF/1 i[3456]86-*osf1mk*
3934 HP/Apollo 68k Family m68*-apollo*-sysv*,
3936 m68*-hp-bsd*, m68*-hp-hpux*
3937 I960 with MON960 i960-*-coff
3939 * OBSOLETE languages
3941 CHILL, a Pascal like language used by telecommunications companies.
3943 * REMOVED configurations and files
3945 AMD 29k family via UDI a29k-amd-udi, udi29k
3946 A29K VxWorks a29k-*-vxworks
3947 AMD 29000 embedded, using EBMON a29k-none-none
3948 AMD 29000 embedded with COFF a29k-none-coff
3949 AMD 29000 embedded with a.out a29k-none-aout
3951 testsuite/gdb.hp/gdb.threads-hp/ directory
3953 * New command "set max-user-call-depth <nnn>"
3955 This command allows the user to limit the call depth of user-defined
3956 commands. The default is 1024.
3958 * Changes in FreeBSD/i386 native debugging.
3960 Support for the "generate-core-file" has been added.
3962 * New commands "dump", "append", and "restore".
3964 These commands allow data to be copied from target memory
3965 to a bfd-format or binary file (dump and append), and back
3966 from a file into memory (restore).
3968 * Improved "next/step" support on multi-processor Alpha Tru64.
3970 The previous single-step mechanism could cause unpredictable problems,
3971 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3972 of a software single-step mechanism prevents this.
3974 *** Changes in GDB 5.2.1:
3982 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3983 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3984 Fix, by Joel Brobecker imported from mainline.
3986 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3987 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3988 Fix, by Fred Fish, imported from mainline.
3990 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3991 Surprisingly enough, it works now.
3992 By Michal Ludvig, imported from mainline.
3994 i386 hardware watchpoint support:
3995 avoid misses on second run for some targets.
3996 By Pierre Muller, imported from mainline.
3998 *** Changes in GDB 5.2:
4000 * New command "set trust-readonly-sections on[off]".
4002 This command is a hint that tells gdb that read-only sections
4003 really are read-only (ie. that their contents will not change).
4004 In this mode, gdb will go to the object file rather than the
4005 target to read memory from read-only sections (such as ".text").
4006 This can be a significant performance improvement on some
4007 (notably embedded) targets.
4009 * New command "generate-core-file" (or "gcore").
4011 This new gdb command allows the user to drop a core file of the child
4012 process state at any time. So far it's been implemented only for
4013 GNU/Linux and Solaris, but should be relatively easily ported to other
4014 hosts. Argument is core file name (defaults to core.<pid>).
4016 * New command line option
4018 GDB now accepts --pid or -p followed by a process id.
4020 * Change in command line behavior -- corefiles vs. process ids.
4022 There is a subtle behavior in the way in which GDB handles
4023 command line arguments. The first non-flag argument is always
4024 a program to debug, but the second non-flag argument may either
4025 be a corefile or a process id. Previously, GDB would attempt to
4026 open the second argument as a corefile, and if that failed, would
4027 issue a superfluous error message and then attempt to attach it as
4028 a process. Now, if the second argument begins with a non-digit,
4029 it will be treated as a corefile. If it begins with a digit,
4030 GDB will attempt to attach it as a process, and if no such process
4031 is found, will then attempt to open it as a corefile.
4033 * Changes in ARM configurations.
4035 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4036 configuration is fully multi-arch.
4038 * New native configurations
4040 ARM NetBSD arm*-*-netbsd*
4041 x86 OpenBSD i[3456]86-*-openbsd*
4042 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4043 Sparc64 running FreeBSD sparc64-*-freebsd*
4047 Sanyo XStormy16 xstormy16-elf
4049 * OBSOLETE configurations and files
4051 Configurations that have been declared obsolete in this release have
4052 been commented out. Unless there is activity to revive these
4053 configurations, the next release of GDB will have their sources
4054 permanently REMOVED.
4056 AMD 29k family via UDI a29k-amd-udi, udi29k
4057 A29K VxWorks a29k-*-vxworks
4058 AMD 29000 embedded, using EBMON a29k-none-none
4059 AMD 29000 embedded with COFF a29k-none-coff
4060 AMD 29000 embedded with a.out a29k-none-aout
4062 testsuite/gdb.hp/gdb.threads-hp/ directory
4064 * REMOVED configurations and files
4066 TI TMS320C80 tic80-*-*
4068 PowerPC Solaris powerpcle-*-solaris*
4069 PowerPC Windows NT powerpcle-*-cygwin32
4070 PowerPC Netware powerpc-*-netware*
4071 Harris/CXUX m88k m88*-harris-cxux*
4072 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4073 ns32k-utek-sysv* ns32k-utek-*
4074 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4075 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4076 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4077 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4078 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4080 * Changes to command line processing
4082 The new `--args' feature can be used to specify command-line arguments
4083 for the inferior from gdb's command line.
4085 * Changes to key bindings
4087 There is a new `operate-and-get-next' function bound to `C-o'.
4089 *** Changes in GDB 5.1.1
4091 Fix compile problem on DJGPP.
4093 Fix a problem with floating-point registers on the i386 being
4096 Fix to stop GDB crashing on .debug_str debug info.
4098 Numerous documentation fixes.
4100 Numerous testsuite fixes.
4102 *** Changes in GDB 5.1:
4104 * New native configurations
4106 Alpha FreeBSD alpha*-*-freebsd*
4107 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4108 MIPS GNU/Linux mips*-*-linux*
4109 MIPS SGI Irix 6.x mips*-sgi-irix6*
4110 ia64 AIX ia64-*-aix*
4111 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4115 Motorola 68HC11 and 68HC12 m68hc11-elf
4117 UltraSparc running GNU/Linux sparc64-*-linux*
4119 * OBSOLETE configurations and files
4121 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4122 Harris/CXUX m88k m88*-harris-cxux*
4123 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4124 ns32k-utek-sysv* ns32k-utek-*
4125 TI TMS320C80 tic80-*-*
4127 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4128 PowerPC Solaris powerpcle-*-solaris*
4129 PowerPC Windows NT powerpcle-*-cygwin32
4130 PowerPC Netware powerpc-*-netware*
4131 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4132 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4133 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4134 Apple Macintosh (MPW) host N/A
4136 stuff.c (Program to stuff files into a specially prepared space in kdb)
4137 kdb-start.c (Main loop for the standalone kernel debugger)
4139 Configurations that have been declared obsolete in this release have
4140 been commented out. Unless there is activity to revive these
4141 configurations, the next release of GDB will have their sources
4142 permanently REMOVED.
4144 * REMOVED configurations and files
4146 Altos 3068 m68*-altos-*
4147 Convex c1-*-*, c2-*-*
4149 ARM RISCix arm-*-* (as host)
4153 * GDB has been converted to ISO C.
4155 GDB's source code has been converted to ISO C. In particular, the
4156 sources are fully protoized, and rely on standard headers being
4161 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4163 * The MI enabled by default.
4165 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4166 revised and enabled by default. Packages which use GDB as a debugging
4167 engine behind a UI or another front end are encouraged to switch to
4168 using the GDB/MI interface, instead of the old annotations interface
4169 which is now deprecated.
4171 * Support for debugging Pascal programs.
4173 GDB now includes support for debugging Pascal programs. The following
4174 main features are supported:
4176 - Pascal-specific data types such as sets;
4178 - automatic recognition of Pascal sources based on file-name
4181 - Pascal-style display of data types, variables, and functions;
4183 - a Pascal expression parser.
4185 However, some important features are not yet supported.
4187 - Pascal string operations are not supported at all;
4189 - there are some problems with boolean types;
4191 - Pascal type hexadecimal constants are not supported
4192 because they conflict with the internal variables format;
4194 - support for Pascal objects and classes is not full yet;
4196 - unlike Pascal, GDB is case-sensitive for symbol names.
4198 * Changes in completion.
4200 Commands such as `shell', `run' and `set args', which pass arguments
4201 to inferior programs, now complete on file names, similar to what
4202 users expect at the shell prompt.
4204 Commands which accept locations, such as `disassemble', `print',
4205 `breakpoint', `until', etc. now complete on filenames as well as
4206 program symbols. Thus, if you type "break foob TAB", and the source
4207 files linked into the programs include `foobar.c', that file name will
4208 be one of the candidates for completion. However, file names are not
4209 considered for completion after you typed a colon that delimits a file
4210 name from a name of a function in that file, as in "break foo.c:bar".
4212 `set demangle-style' completes on available demangling styles.
4214 * New platform-independent commands:
4216 It is now possible to define a post-hook for a command as well as a
4217 hook that runs before the command. For more details, see the
4218 documentation of `hookpost' in the GDB manual.
4220 * Changes in GNU/Linux native debugging.
4222 Support for debugging multi-threaded programs has been completely
4223 revised for all platforms except m68k and sparc. You can now debug as
4224 many threads as your system allows you to have.
4226 Attach/detach is supported for multi-threaded programs.
4228 Support for SSE registers was added for x86. This doesn't work for
4229 multi-threaded programs though.
4231 * Changes in MIPS configurations.
4233 Multi-arch support is enabled for all MIPS configurations.
4235 GDB can now be built as native debugger on SGI Irix 6.x systems for
4236 debugging n32 executables. (Debugging 64-bit executables is not yet
4239 * Unified support for hardware watchpoints in all x86 configurations.
4241 Most (if not all) native x86 configurations support hardware-assisted
4242 breakpoints and watchpoints in a unified manner. This support
4243 implements debug register sharing between watchpoints, which allows to
4244 put a virtually infinite number of watchpoints on the same address,
4245 and also supports watching regions up to 16 bytes with several debug
4248 The new maintenance command `maintenance show-debug-regs' toggles
4249 debugging print-outs in functions that insert, remove, and test
4250 watchpoints and hardware breakpoints.
4252 * Changes in the DJGPP native configuration.
4254 New command ``info dos sysinfo'' displays assorted information about
4255 the CPU, OS, memory, and DPMI server.
4257 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4258 display information about segment descriptors stored in GDT, LDT, and
4261 New commands ``info dos pde'' and ``info dos pte'' display entries
4262 from Page Directory and Page Tables (for now works with CWSDPMI only).
4263 New command ``info dos address-pte'' displays the Page Table entry for
4264 a given linear address.
4266 GDB can now pass command lines longer than 126 characters to the
4267 program being debugged (requires an update to the libdbg.a library
4268 which is part of the DJGPP development kit).
4270 DWARF2 debug info is now supported.
4272 It is now possible to `step' and `next' through calls to `longjmp'.
4274 * Changes in documentation.
4276 All GDB documentation was converted to GFDL, the GNU Free
4277 Documentation License.
4279 Tracepoints-related commands are now fully documented in the GDB
4282 TUI, the Text-mode User Interface, is now documented in the manual.
4284 Tracepoints-related commands are now fully documented in the GDB
4287 The "GDB Internals" manual now has an index. It also includes
4288 documentation of `ui_out' functions, GDB coding standards, x86
4289 hardware watchpoints, and memory region attributes.
4291 * GDB's version number moved to ``version.in''
4293 The Makefile variable VERSION has been replaced by the file
4294 ``version.in''. People creating GDB distributions should update the
4295 contents of this file.
4299 GUD support is now a standard part of the EMACS distribution.
4301 *** Changes in GDB 5.0:
4303 * Improved support for debugging FP programs on x86 targets
4305 Unified and much-improved support for debugging floating-point
4306 programs on all x86 targets. In particular, ``info float'' now
4307 displays the FP registers in the same format on all x86 targets, with
4308 greater level of detail.
4310 * Improvements and bugfixes in hardware-assisted watchpoints
4312 It is now possible to watch array elements, struct members, and
4313 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4314 on x86 targets no longer erroneously trigger when the address is
4317 * Improvements in the native DJGPP version of GDB
4319 The distribution now includes all the scripts and auxiliary files
4320 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4321 machines ``out of the box''.
4323 The DJGPP version can now debug programs that use signals. It is
4324 possible to catch signals that happened in the debuggee, deliver
4325 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4326 would kill the program being debugged.) Programs that hook hardware
4327 interrupts (keyboard, timer, etc.) can also be debugged.
4329 It is now possible to debug DJGPP programs that redirect their
4330 standard handles or switch them to raw (as opposed to cooked) mode, or
4331 even close them. The command ``run < foo > bar'' works as expected,
4332 and ``info terminal'' reports useful information about the debuggee's
4333 terminal, including raw/cooked mode, redirection, etc.
4335 The DJGPP version now uses termios functions for console I/O, which
4336 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4339 DOS-style file names with drive letters are now fully supported by
4342 It is now possible to debug DJGPP programs that switch their working
4343 directory. It is also possible to rerun the debuggee any number of
4344 times without restarting GDB; thus, you can use the same setup,
4345 breakpoints, etc. for many debugging sessions.
4347 * New native configurations
4349 ARM GNU/Linux arm*-*-linux*
4350 PowerPC GNU/Linux powerpc-*-linux*
4354 Motorola MCore mcore-*-*
4355 x86 VxWorks i[3456]86-*-vxworks*
4356 PowerPC VxWorks powerpc-*-vxworks*
4357 TI TMS320C80 tic80-*-*
4359 * OBSOLETE configurations
4361 Altos 3068 m68*-altos-*
4362 Convex c1-*-*, c2-*-*
4364 ARM RISCix arm-*-* (as host)
4367 Configurations that have been declared obsolete will be commented out,
4368 but the code will be left in place. If there is no activity to revive
4369 these configurations before the next release of GDB, the sources will
4370 be permanently REMOVED.
4372 * Gould support removed
4374 Support for the Gould PowerNode and NP1 has been removed.
4376 * New features for SVR4
4378 On SVR4 native platforms (such as Solaris), if you attach to a process
4379 without first loading a symbol file, GDB will now attempt to locate and
4380 load symbols from the running process's executable file.
4382 * Many C++ enhancements
4384 C++ support has been greatly improved. Overload resolution now works properly
4385 in almost all cases. RTTI support is on the way.
4387 * Remote targets can connect to a sub-program
4389 A popen(3) style serial-device has been added. This device starts a
4390 sub-process (such as a stand-alone simulator) and then communicates
4391 with that. The sub-program to run is specified using the syntax
4392 ``|<program> <args>'' vis:
4394 (gdb) set remotedebug 1
4395 (gdb) target extended-remote |mn10300-elf-sim program-args
4397 * MIPS 64 remote protocol
4399 A long standing bug in the mips64 remote protocol where by GDB
4400 expected certain 32 bit registers (ex SR) to be transfered as 32
4401 instead of 64 bits has been fixed.
4403 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4404 added to provide backward compatibility with older versions of GDB.
4406 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4408 The command ``set remotebinarydownload'' command has been replaced by
4409 ``set remote X-packet''. Other commands in ``set remote'' family
4410 include ``set remote P-packet''.
4412 * Breakpoint commands accept ranges.
4414 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4415 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4416 ``tracepoint passcount'' also accepts a range of tracepoints.
4418 * ``apropos'' command added.
4420 The ``apropos'' command searches through command names and
4421 documentation strings, printing out matches, making it much easier to
4422 try to find a command that does what you are looking for.
4426 A new machine oriented interface (MI) has been added to GDB. This
4427 interface is designed for debug environments running GDB as a separate
4428 process. This is part of the long term libGDB project. See the
4429 "GDB/MI" chapter of the GDB manual for further information. It can be
4430 enabled by configuring with:
4432 .../configure --enable-gdbmi
4434 *** Changes in GDB-4.18:
4436 * New native configurations
4438 HP-UX 10.20 hppa*-*-hpux10.20
4439 HP-UX 11.x hppa*-*-hpux11.0*
4440 M68K GNU/Linux m68*-*-linux*
4444 Fujitsu FR30 fr30-*-elf*
4445 Intel StrongARM strongarm-*-*
4446 Mitsubishi D30V d30v-*-*
4448 * OBSOLETE configurations
4450 Gould PowerNode, NP1 np1-*-*, pn-*-*
4452 Configurations that have been declared obsolete will be commented out,
4453 but the code will be left in place. If there is no activity to revive
4454 these configurations before the next release of GDB, the sources will
4455 be permanently REMOVED.
4459 As a compatibility experiment, GDB's source files buildsym.h and
4460 buildsym.c have been converted to pure standard C, no longer
4461 containing any K&R compatibility code. We believe that all systems in
4462 use today either come with a standard C compiler, or have a GCC port
4463 available. If this is not true, please report the affected
4464 configuration to bug-gdb@gnu.org immediately. See the README file for
4465 information about getting a standard C compiler if you don't have one
4470 GDB now uses readline 2.2.
4472 * set extension-language
4474 You can now control the mapping between filename extensions and source
4475 languages by using the `set extension-language' command. For instance,
4476 you can ask GDB to treat .c files as C++ by saying
4477 set extension-language .c c++
4478 The command `info extensions' lists all of the recognized extensions
4479 and their associated languages.
4481 * Setting processor type for PowerPC and RS/6000
4483 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4484 you can use the `set processor' command to specify what variant of the
4485 PowerPC family you are debugging. The command
4489 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4490 following PowerPC and RS6000 variants:
4492 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4493 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4495 403GC IBM PowerPC 403GC
4496 505 Motorola PowerPC 505
4497 860 Motorola PowerPC 860 or 850
4498 601 Motorola PowerPC 601
4499 602 Motorola PowerPC 602
4500 603 Motorola/IBM PowerPC 603 or 603e
4501 604 Motorola PowerPC 604 or 604e
4502 750 Motorola/IBM PowerPC 750 or 750
4504 At the moment, this command just tells GDB what to name the
4505 special-purpose processor registers. Since almost all the affected
4506 registers are inaccessible to user-level programs, this command is
4507 only useful for remote debugging in its present form.
4511 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4512 more extensive support for HP-UX. Added features include shared
4513 library support, kernel threads and hardware watchpoints for 11.00,
4514 support for HP's ANSI C and C++ compilers, and a compatibility mode
4515 for xdb and dbx commands.
4519 HP's donation includes the new concept of catchpoints, which is a
4520 generalization of the old catch command. On HP-UX, it is now possible
4521 to catch exec, fork, and vfork, as well as library loading.
4523 This means that the existing catch command has changed; its first
4524 argument now specifies the type of catch to be set up. See the
4525 output of "help catch" for a list of catchpoint types.
4527 * Debugging across forks
4529 On HP-UX, you can choose which process to debug when a fork() happens
4534 HP has donated a curses-based terminal user interface (TUI). To get
4535 it, build with --enable-tui. Although this can be enabled for any
4536 configuration, at present it only works for native HP debugging.
4538 * GDB remote protocol additions
4540 A new protocol packet 'X' that writes binary data is now available.
4541 Default behavior is to try 'X', then drop back to 'M' if the stub
4542 fails to respond. The settable variable `remotebinarydownload'
4543 allows explicit control over the use of 'X'.
4545 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4546 full 64-bit address. The command
4548 set remoteaddresssize 32
4550 can be used to revert to the old behaviour. For existing remote stubs
4551 the change should not be noticed, as the additional address information
4554 In order to assist in debugging stubs, you may use the maintenance
4555 command `packet' to send any text string to the stub. For instance,
4557 maint packet heythere
4559 sends the packet "$heythere#<checksum>". Note that it is very easy to
4560 disrupt a debugging session by sending the wrong packet at the wrong
4563 The compare-sections command allows you to compare section data on the
4564 target to what is in the executable file without uploading or
4565 downloading, by comparing CRC checksums.
4567 * Tracing can collect general expressions
4569 You may now collect general expressions at tracepoints. This requires
4570 further additions to the target-side stub; see tracepoint.c and
4571 doc/agentexpr.texi for further details.
4573 * mask-address variable for Mips
4575 For Mips targets, you may control the zeroing of the upper 32 bits of
4576 a 64-bit address by entering `set mask-address on'. This is mainly
4577 of interest to users of embedded R4xxx and R5xxx processors.
4579 * Higher serial baud rates
4581 GDB's serial code now allows you to specify baud rates 57600, 115200,
4582 230400, and 460800 baud. (Note that your host system may not be able
4583 to achieve all of these rates.)
4587 The i960 configuration now includes an initial implementation of a
4588 builtin simulator, contributed by Jim Wilson.
4591 *** Changes in GDB-4.17:
4593 * New native configurations
4595 Alpha GNU/Linux alpha*-*-linux*
4596 Unixware 2.x i[3456]86-unixware2*
4597 Irix 6.x mips*-sgi-irix6*
4598 PowerPC GNU/Linux powerpc-*-linux*
4599 PowerPC Solaris powerpcle-*-solaris*
4600 Sparc GNU/Linux sparc-*-linux*
4601 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4605 Argonaut Risc Chip (ARC) arc-*-*
4606 Hitachi H8/300S h8300*-*-*
4607 Matsushita MN10200 w/simulator mn10200-*-*
4608 Matsushita MN10300 w/simulator mn10300-*-*
4609 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4610 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4611 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4612 Mitsubishi D10V w/simulator d10v-*-*
4613 Mitsubishi M32R/D w/simulator m32r-*-elf*
4614 Tsqware Sparclet sparclet-*-*
4615 NEC V850 w/simulator v850-*-*
4617 * New debugging protocols
4619 ARM with RDI protocol arm*-*-*
4620 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4621 DDB and LSI variants of PMON protocol mips*-*-*
4622 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4623 PowerPC with SDS protocol powerpc{,le}-*-eabi
4624 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4628 All configurations can now understand and use the DWARF 2 debugging
4629 format. The choice is automatic, if the symbol file contains DWARF 2
4634 GDB now includes basic Java language support. This support is
4635 only useful with Java compilers that produce native machine code.
4637 * solib-absolute-prefix and solib-search-path
4639 For SunOS and SVR4 shared libraries, you may now set the prefix for
4640 loading absolute shared library symbol files, and the search path for
4641 locating non-absolute shared library symbol files.
4643 * Live range splitting
4645 GDB can now effectively debug code for which GCC has performed live
4646 range splitting as part of its optimization. See gdb/doc/LRS for
4647 more details on the expected format of the stabs information.
4651 GDB's support for the GNU Hurd, including thread debugging, has been
4652 updated to work with current versions of the Hurd.
4656 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4657 instruction set. ARM GDB automatically detects when Thumb
4658 instructions are in use, and adjusts disassembly and backtracing
4663 GDB's MIPS target configurations now handle the MIP16 16-bit
4668 GDB now includes support for overlays; if an executable has been
4669 linked such that multiple sections are based at the same address, GDB
4670 will decide which section to use for symbolic info. You can choose to
4671 control the decision manually, using overlay commands, or implement
4672 additional target-side support and use "overlay load-target" to bring
4673 in the overlay mapping. Do "help overlay" for more detail.
4677 The command "info symbol <address>" displays information about
4678 the symbol at the specified address.
4682 The standard remote protocol now includes an extension that allows
4683 asynchronous collection and display of trace data. This requires
4684 extensive support in the target-side debugging stub. Tracing mode
4685 includes a new interaction mode in GDB and new commands: see the
4686 file tracepoint.c for more details.
4690 Configurations for embedded MIPS now include a simulator contributed
4691 by Cygnus Solutions. The simulator supports the instruction sets
4692 of most MIPS variants.
4696 Sparc configurations may now include the ERC32 simulator contributed
4697 by the European Space Agency. The simulator is not built into
4698 Sparc targets by default; configure with --enable-sim to include it.
4702 For target configurations that may include multiple variants of a
4703 basic architecture (such as MIPS and SH), you may now set the
4704 architecture explicitly. "set arch" sets, "info arch" lists
4705 the possible architectures.
4707 *** Changes in GDB-4.16:
4709 * New native configurations
4711 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4712 M68K NetBSD m68k-*-netbsd*
4713 PowerPC AIX 4.x powerpc-*-aix*
4714 PowerPC MacOS powerpc-*-macos*
4715 PowerPC Windows NT powerpcle-*-cygwin32
4716 RS/6000 AIX 4.x rs6000-*-aix4*
4720 ARM with RDP protocol arm-*-*
4721 I960 with MON960 i960-*-coff
4722 MIPS VxWorks mips*-*-vxworks*
4723 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4724 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4726 Matra Sparclet sparclet-*-*
4730 The powerpc-eabi configuration now includes the PSIM simulator,
4731 contributed by Andrew Cagney, with assistance from Mike Meissner.
4732 PSIM is a very elaborate model of the PowerPC, including not only
4733 basic instruction set execution, but also details of execution unit
4734 performance and I/O hardware. See sim/ppc/README for more details.
4738 GDB now works with Solaris 2.5.
4740 * Windows 95/NT native
4742 GDB will now work as a native debugger on Windows 95 and Windows NT.
4743 To build it from source, you must use the "gnu-win32" environment,
4744 which uses a DLL to emulate enough of Unix to run the GNU tools.
4745 Further information, binaries, and sources are available at
4746 ftp.cygnus.com, under pub/gnu-win32.
4748 * dont-repeat command
4750 If a user-defined command includes the command `dont-repeat', then the
4751 command will not be repeated if the user just types return. This is
4752 useful if the command is time-consuming to run, so that accidental
4753 extra keystrokes don't run the same command many times.
4755 * Send break instead of ^C
4757 The standard remote protocol now includes an option to send a break
4758 rather than a ^C to the target in order to interrupt it. By default,
4759 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4761 * Remote protocol timeout
4763 The standard remote protocol includes a new variable `remotetimeout'
4764 that allows you to set the number of seconds before GDB gives up trying
4765 to read from the target. The default value is 2.
4767 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4769 By default GDB will automatically keep track of objects as they are
4770 loaded and unloaded by the dynamic linker. By using the command `set
4771 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4772 when shared library events occur, thus allowing you to set breakpoints
4773 in shared libraries which are explicitly loaded by the inferior.
4775 Note this feature does not work on hpux8. On hpux9 you must link
4776 /usr/lib/end.o into your program. This feature should work
4777 automatically on hpux10.
4779 * Irix 5.x hardware watchpoint support
4781 Irix 5 configurations now support the use of hardware watchpoints.
4783 * Mips protocol "SYN garbage limit"
4785 When debugging a Mips target using the `target mips' protocol, you
4786 may set the number of characters that GDB will ignore by setting
4787 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4788 every character. The default value is 1050.
4790 * Recording and replaying remote debug sessions
4792 If you set `remotelogfile' to the name of a file, gdb will write to it
4793 a recording of a remote debug session. This recording may then be
4794 replayed back to gdb using "gdbreplay". See gdbserver/README for
4795 details. This is useful when you have a problem with GDB while doing
4796 remote debugging; you can make a recording of the session and send it
4797 to someone else, who can then recreate the problem.
4799 * Speedups for remote debugging
4801 GDB includes speedups for downloading and stepping MIPS systems using
4802 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4803 and more efficient S-record downloading.
4805 * Memory use reductions and statistics collection
4807 GDB now uses less memory and reports statistics about memory usage.
4808 Try the `maint print statistics' command, for example.
4810 *** Changes in GDB-4.15:
4812 * Psymtabs for XCOFF
4814 The symbol reader for AIX GDB now uses partial symbol tables. This
4815 can greatly improve startup time, especially for large executables.
4817 * Remote targets use caching
4819 Remote targets now use a data cache to speed up communication with the
4820 remote side. The data cache could lead to incorrect results because
4821 it doesn't know about volatile variables, thus making it impossible to
4822 debug targets which use memory mapped I/O devices. `set remotecache
4823 off' turns the the data cache off.
4825 * Remote targets may have threads
4827 The standard remote protocol now includes support for multiple threads
4828 in the target system, using new protocol commands 'H' and 'T'. See
4829 gdb/remote.c for details.
4833 If GDB is configured with `--enable-netrom', then it will include
4834 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4835 acts as though it is a bank of ROM on the target board, but you can
4836 write into it over the network. GDB's support consists only of
4837 support for fast loading into the emulated ROM; to debug, you must use
4838 another protocol, such as standard remote protocol. The usual
4839 sequence is something like
4841 target nrom <netrom-hostname>
4843 target remote <netrom-hostname>:1235
4847 GDB now includes support for the Apple Macintosh, as a host only. It
4848 may be run as either an MPW tool or as a standalone application, and
4849 it can debug through the serial port. All the usual GDB commands are
4850 available, but to the target command, you must supply "serial" as the
4851 device type instead of "/dev/ttyXX". See mpw-README in the main
4852 directory for more information on how to build. The MPW configuration
4853 scripts */mpw-config.in support only a few targets, and only the
4854 mips-idt-ecoff target has been tested.
4858 GDB configuration now uses autoconf. This is not user-visible,
4859 but does simplify configuration and building.
4863 GDB now supports hpux10.
4865 *** Changes in GDB-4.14:
4867 * New native configurations
4869 x86 FreeBSD i[345]86-*-freebsd
4870 x86 NetBSD i[345]86-*-netbsd
4871 NS32k NetBSD ns32k-*-netbsd
4872 Sparc NetBSD sparc-*-netbsd
4876 A29K VxWorks a29k-*-vxworks
4877 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4878 CPU32 EST-300 emulator m68*-*-est*
4879 PowerPC ELF powerpc-*-elf
4882 * Alpha OSF/1 support for procfs
4884 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4885 possible to attach to running processes. As the mounting of the /proc
4886 filesystem is optional on the Alpha, GDB automatically determines
4887 the availability of /proc during startup. This can lead to problems
4888 if /proc is unmounted after GDB has been started.
4890 * Arguments to user-defined commands
4892 User commands may accept up to 10 arguments separated by whitespace.
4893 Arguments are accessed within the user command via $arg0..$arg9. A
4896 print $arg0 + $arg1 + $arg2
4898 To execute the command use:
4901 Defines the command "adder" which prints the sum of its three arguments.
4902 Note the arguments are text substitutions, so they may reference variables,
4903 use complex expressions, or even perform inferior function calls.
4905 * New `if' and `while' commands
4907 This makes it possible to write more sophisticated user-defined
4908 commands. Both commands take a single argument, which is the
4909 expression to evaluate, and must be followed by the commands to
4910 execute, one per line, if the expression is nonzero, the list being
4911 terminated by the word `end'. The `if' command list may include an
4912 `else' word, which causes the following commands to be executed only
4913 if the expression is zero.
4915 * Fortran source language mode
4917 GDB now includes partial support for Fortran 77. It will recognize
4918 Fortran programs and can evaluate a subset of Fortran expressions, but
4919 variables and functions may not be handled correctly. GDB will work
4920 with G77, but does not yet know much about symbols emitted by other
4923 * Better HPUX support
4925 Most debugging facilities now work on dynamic executables for HPPAs
4926 running hpux9 or later. You can attach to running dynamically linked
4927 processes, but by default the dynamic libraries will be read-only, so
4928 for instance you won't be able to put breakpoints in them. To change
4929 that behavior do the following before running the program:
4935 This will cause the libraries to be mapped private and read-write.
4936 To revert to the normal behavior, do this:
4942 You cannot set breakpoints or examine data in the library until after
4943 the library is loaded if the function/data symbols do not have
4946 GDB can now also read debug symbols produced by the HP C compiler on
4947 HPPAs (sorry, no C++, Fortran or 68k support).
4949 * Target byte order now dynamically selectable
4951 You can choose which byte order to use with a target system, via the
4952 commands "set endian big" and "set endian little", and you can see the
4953 current setting by using "show endian". You can also give the command
4954 "set endian auto", in which case GDB will use the byte order
4955 associated with the executable. Currently, only embedded MIPS
4956 configurations support dynamic selection of target byte order.
4958 * New DOS host serial code
4960 This version uses DPMI interrupts to handle buffered I/O, so you
4961 no longer need to run asynctsr when debugging boards connected to
4964 *** Changes in GDB-4.13:
4966 * New "complete" command
4968 This lists all the possible completions for the rest of the line, if it
4969 were to be given as a command itself. This is intended for use by emacs.
4971 * Trailing space optional in prompt
4973 "set prompt" no longer adds a space for you after the prompt you set. This
4974 allows you to set a prompt which ends in a space or one that does not.
4976 * Breakpoint hit counts
4978 "info break" now displays a count of the number of times the breakpoint
4979 has been hit. This is especially useful in conjunction with "ignore"; you
4980 can ignore a large number of breakpoint hits, look at the breakpoint info
4981 to see how many times the breakpoint was hit, then run again, ignoring one
4982 less than that number, and this will get you quickly to the last hit of
4985 * Ability to stop printing at NULL character
4987 "set print null-stop" will cause GDB to stop printing the characters of
4988 an array when the first NULL is encountered. This is useful when large
4989 arrays actually contain only short strings.
4991 * Shared library breakpoints
4993 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4994 breakpoints in shared libraries before the executable is run.
4996 * Hardware watchpoints
4998 There is a new hardware breakpoint for the watch command for sparclite
4999 targets. See gdb/sparclite/hw_breakpoint.note.
5001 Hardware watchpoints are also now supported under GNU/Linux.
5005 Annotations have been added. These are for use with graphical interfaces,
5006 and are still experimental. Currently only gdba.el uses these.
5008 * Improved Irix 5 support
5010 GDB now works properly with Irix 5.2.
5012 * Improved HPPA support
5014 GDB now works properly with the latest GCC and GAS.
5016 * New native configurations
5018 Sequent PTX4 i[34]86-sequent-ptx4
5019 HPPA running OSF/1 hppa*-*-osf*
5020 Atari TT running SVR4 m68*-*-sysv4*
5021 RS/6000 LynxOS rs6000-*-lynxos*
5025 OS/9000 i[34]86-*-os9k
5026 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5029 * Hitachi SH7000 and E7000-PC ICE support
5031 There is now support for communicating with the Hitachi E7000-PC ICE.
5032 This is available automatically when GDB is configured for the SH.
5036 As usual, a variety of small fixes and improvements, both generic
5037 and configuration-specific. See the ChangeLog for more detail.
5039 *** Changes in GDB-4.12:
5041 * Irix 5 is now supported
5045 GDB-4.12 on the HPPA has a number of changes which make it unable
5046 to debug the output from the currently released versions of GCC and
5047 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5048 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5049 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5052 *** Changes in GDB-4.11:
5054 * User visible changes:
5058 The "set remotedebug" option is now consistent between the mips remote
5059 target, remote targets using the gdb-specific protocol, UDI (AMD's
5060 debug protocol for the 29k) and the 88k bug monitor. It is now an
5061 integer specifying a debug level (normally 0 or 1, but 2 means more
5062 debugging info for the mips target).
5064 * DEC Alpha native support
5066 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5067 debug info, but GDB works fairly well with the DEC compiler and should
5068 work with a future GCC release. See the README file for a few
5069 Alpha-specific notes.
5071 * Preliminary thread implementation
5073 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5075 * LynxOS native and target support for 386
5077 This release has been hosted on LynxOS 2.2, and also can be configured
5078 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5081 * Improvements in C++ mangling/demangling.
5083 This release has much better g++ debugging, specifically in name
5084 mangling/demangling, virtual function calls, print virtual table,
5085 call methods, ...etc.
5087 *** Changes in GDB-4.10:
5089 * User visible changes:
5091 Remote debugging using the GDB-specific (`target remote') protocol now
5092 supports the `load' command. This is only useful if you have some
5093 other way of getting the stub to the target system, and you can put it
5094 somewhere in memory where it won't get clobbered by the download.
5096 Filename completion now works.
5098 When run under emacs mode, the "info line" command now causes the
5099 arrow to point to the line specified. Also, "info line" prints
5100 addresses in symbolic form (as well as hex).
5102 All vxworks based targets now support a user settable option, called
5103 vxworks-timeout. This option represents the number of seconds gdb
5104 should wait for responses to rpc's. You might want to use this if
5105 your vxworks target is, perhaps, a slow software simulator or happens
5106 to be on the far side of a thin network line.
5110 This release contains support for using a DEC alpha as a GDB host for
5111 cross debugging. Native alpha debugging is not supported yet.
5114 *** Changes in GDB-4.9:
5118 This is the first GDB release which is accompanied by a matching testsuite.
5119 The testsuite requires installation of dejagnu, which should be available
5120 via ftp from most sites that carry GNU software.
5124 'Cfront' style demangling has had its name changed to 'ARM' style, to
5125 emphasize that it was written from the specifications in the C++ Annotated
5126 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5127 disclaimers, it still generated too much confusion with users attempting to
5128 use gdb with AT&T cfront.
5132 GDB now uses a standard remote interface to a simulator library.
5133 So far, the library contains simulators for the Zilog Z8001/2, the
5134 Hitachi H8/300, H8/500 and Super-H.
5136 * New targets supported
5138 H8/300 simulator h8300-hitachi-hms or h8300hms
5139 H8/500 simulator h8500-hitachi-hms or h8500hms
5140 SH simulator sh-hitachi-hms or sh
5141 Z8000 simulator z8k-zilog-none or z8ksim
5142 IDT MIPS board over serial line mips-idt-ecoff
5144 Cross-debugging to GO32 targets is supported. It requires a custom
5145 version of the i386-stub.c module which is integrated with the
5146 GO32 memory extender.
5148 * New remote protocols
5150 MIPS remote debugging protocol.
5152 * New source languages supported
5154 This version includes preliminary support for Chill, a Pascal like language
5155 used by telecommunications companies. Chill support is also being integrated
5156 into the GNU compiler, but we don't know when it will be publically available.
5159 *** Changes in GDB-4.8:
5161 * HP Precision Architecture supported
5163 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5164 version of this support was available as a set of patches from the
5165 University of Utah. GDB does not support debugging of programs
5166 compiled with the HP compiler, because HP will not document their file
5167 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5168 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5170 Many problems in the preliminary version have been fixed.
5172 * Faster and better demangling
5174 We have improved template demangling and fixed numerous bugs in the GNU style
5175 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5176 character types (wchar_t) are now supported. Demangling of each symbol is now
5177 only done once, and is cached when the symbol table for a file is read in.
5178 This results in a small increase in memory usage for C programs, a moderate
5179 increase in memory usage for C++ programs, and a fantastic speedup in
5182 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5183 from the specifications in the Annotated Reference Manual, which AT&T's
5184 compiler does not actually implement.
5186 * G++ multiple inheritance compiler problem
5188 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5189 inheritance lattices was reworked to properly discover ambiguities. We
5190 recently found an example which causes this new algorithm to fail in a
5191 very subtle way, producing bad debug information for those classes.
5192 The file 'gcc.patch' (in this directory) can be applied to gcc to
5193 circumvent the problem. A future GCC release will contain a complete
5196 The previous G++ debug info problem (mentioned below for the gdb-4.7
5197 release) is fixed in gcc version 2.3.2.
5199 * Improved configure script
5201 The `configure' script will now attempt to guess your system type if
5202 you don't supply a host system type. The old scheme of supplying a
5203 host system triplet is preferable over using this. All the magic is
5204 done in the new `config.guess' script. Examine it for details.
5206 We have also brought our configure script much more in line with the FSF's
5207 version. It now supports the --with-xxx options. In particular,
5208 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5209 The resulting GDB will not be able to read arbitrary object file formats --
5210 only the format ``expected'' to be used on the configured target system.
5211 We hope to make this the default in a future release.
5213 * Documentation improvements
5215 There's new internal documentation on how to modify GDB, and how to
5216 produce clean changes to the code. We implore people to read it
5217 before submitting changes.
5219 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5220 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5221 `info' files are also provided. To build `info' files from scratch,
5222 you will need the latest `makeinfo' release, which will be available in
5223 a future texinfo-X.Y release.
5225 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5226 We're not sure exactly which versions have this problem, but it has
5227 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5228 or better. If that isn't possible, there is a patch in
5229 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5230 around this problem.
5234 GDB now supports array constants that can be used in expressions typed in by
5235 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5236 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5239 The new directory `gdb/sparclite' contains a program that demonstrates
5240 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5242 * New native hosts supported
5244 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5245 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5247 * New targets supported
5249 AMD 29k family via UDI a29k-amd-udi or udi29k
5251 * New file formats supported
5253 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5254 HPUX core files, and SCO 3.2v2 core files.
5258 Attaching to processes now works again; thanks for the many bug reports.
5260 We have also stomped on a bunch of core dumps caused by
5261 printf_filtered("%s") problems.
5263 We eliminated a copyright problem on the rpc and ptrace header files
5264 for VxWorks, which was discovered at the last minute during the 4.7
5265 release. You should now be able to build a VxWorks GDB.
5267 You can now interrupt gdb while an attached process is running. This
5268 will cause the attached process to stop, and give control back to GDB.
5270 We fixed problems caused by using too many file descriptors
5271 for reading symbols from object files and libraries. This was
5272 especially a problem for programs that used many (~100) shared
5275 The `step' command now only enters a subroutine if there is line number
5276 information for the subroutine. Otherwise it acts like the `next'
5277 command. Previously, `step' would enter subroutines if there was
5278 any debugging information about the routine. This avoids problems
5279 when using `cc -g1' on MIPS machines.
5281 * Internal improvements
5283 GDB's internal interfaces have been improved to make it easier to support
5284 debugging of multiple languages in the future.
5286 GDB now uses a common structure for symbol information internally.
5287 Minimal symbols (derived from linkage symbols in object files), partial
5288 symbols (from a quick scan of debug information), and full symbols
5289 contain a common subset of information, making it easier to write
5290 shared code that handles any of them.
5292 * New command line options
5294 We now accept --silent as an alias for --quiet.
5298 The memory-mapped-malloc library is now licensed under the GNU Library
5299 General Public License.
5301 *** Changes in GDB-4.7:
5303 * Host/native/target split
5305 GDB has had some major internal surgery to untangle the support for
5306 hosts and remote targets. Now, when you configure GDB for a remote
5307 target, it will no longer load in all of the support for debugging
5308 local programs on the host. When fully completed and tested, this will
5309 ensure that arbitrary host/target combinations are possible.
5311 The primary conceptual shift is to separate the non-portable code in
5312 GDB into three categories. Host specific code is required any time GDB
5313 is compiled on that host, regardless of the target. Target specific
5314 code relates to the peculiarities of the target, but can be compiled on
5315 any host. Native specific code is everything else: it can only be
5316 built when the host and target are the same system. Child process
5317 handling and core file support are two common `native' examples.
5319 GDB's use of /proc for controlling Unix child processes is now cleaner.
5320 It has been split out into a single module under the `target_ops' vector,
5321 plus two native-dependent functions for each system that uses /proc.
5323 * New hosts supported
5325 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5326 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5327 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5329 * New targets supported
5331 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5332 68030 and CPU32 m68030-*-*, m68332-*-*
5334 * New native hosts supported
5336 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5337 (386bsd is not well tested yet)
5338 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5340 * New file formats supported
5342 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5343 supports reading of `a.out.adobe' object files, which are an a.out
5344 format extended with minimal information about multiple sections.
5348 `show copying' is the same as the old `info copying'.
5349 `show warranty' is the same as `info warrantee'.
5350 These were renamed for consistency. The old commands continue to work.
5352 `info handle' is a new alias for `info signals'.
5354 You can now define pre-command hooks, which attach arbitrary command
5355 scripts to any command. The commands in the hook will be executed
5356 prior to the user's command. You can also create a hook which will be
5357 executed whenever the program stops. See gdb.texinfo.
5361 We now deal with Cfront style name mangling, and can even extract type
5362 info from mangled symbols. GDB can automatically figure out which
5363 symbol mangling style your C++ compiler uses.
5365 Calling of methods and virtual functions has been improved as well.
5369 The crash that occured when debugging Sun Ansi-C compiled binaries is
5370 fixed. This was due to mishandling of the extra N_SO stabs output
5373 We also finally got Ultrix 4.2 running in house, and fixed core file
5374 support, with help from a dozen people on the net.
5376 John M. Farrell discovered that the reason that single-stepping was so
5377 slow on all of the Mips based platforms (primarily SGI and DEC) was
5378 that we were trying to demangle and lookup a symbol used for internal
5379 purposes on every instruction that was being stepped through. Changing
5380 the name of that symbol so that it couldn't be mistaken for a C++
5381 mangled symbol sped things up a great deal.
5383 Rich Pixley sped up symbol lookups in general by getting much smarter
5384 about when C++ symbol mangling is necessary. This should make symbol
5385 completion (TAB on the command line) much faster. It's not as fast as
5386 we'd like, but it's significantly faster than gdb-4.6.
5390 A new user controllable variable 'call_scratch_address' can
5391 specify the location of a scratch area to be used when GDB
5392 calls a function in the target. This is necessary because the
5393 usual method of putting the scratch area on the stack does not work
5394 in systems that have separate instruction and data spaces.
5396 We integrated changes to support the 29k UDI (Universal Debugger
5397 Interface), but discovered at the last minute that we didn't have all
5398 of the appropriate copyright paperwork. We are working with AMD to
5399 resolve this, and hope to have it available soon.
5403 We have sped up the remote serial line protocol, especially for targets
5404 with lots of registers. It now supports a new `expedited status' ('T')
5405 message which can be used in place of the existing 'S' status message.
5406 This allows the remote stub to send only the registers that GDB
5407 needs to make a quick decision about single-stepping or conditional
5408 breakpoints, eliminating the need to fetch the entire register set for
5409 each instruction being stepped through.
5411 The GDB remote serial protocol now implements a write-through cache for
5412 registers, only re-reading the registers if the target has run.
5414 There is also a new remote serial stub for SPARC processors. You can
5415 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5416 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5417 processor with a serial port.
5421 Configure.in files have become much easier to read and modify. A new
5422 `table driven' format makes it more obvious what configurations are
5423 supported, and what files each one uses.
5427 There is a new opcodes library which will eventually contain all of the
5428 disassembly routines and opcode tables. At present, it only contains
5429 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5430 disassembler (binutils/objdump) to share these routines.
5432 The libiberty library is now copylefted under the GNU Library General
5433 Public License. This allows more liberal use, and was done so libg++
5434 can use it. This makes no difference to GDB, since the Library License
5435 grants all the rights from the General Public License.
5439 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5440 reference to the stabs symbol info used by the debugger. It is (as far
5441 as we know) the only published document on this fascinating topic. We
5442 encourage you to read it, compare it to the stabs information on your
5443 system, and send improvements on the document in general (to
5444 bug-gdb@prep.ai.mit.edu).
5446 And, of course, many bugs have been fixed.
5449 *** Changes in GDB-4.6:
5451 * Better support for C++ function names
5453 GDB now accepts as input the "demangled form" of C++ overloaded function
5454 names and member function names, and can do command completion on such names
5455 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5456 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5457 Make use of command completion, it is your friend.
5459 GDB also now accepts a variety of C++ mangled symbol formats. They are
5460 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5461 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5462 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5463 for the list of formats.
5465 * G++ symbol mangling problem
5467 Recent versions of gcc have a bug in how they emit debugging information for
5468 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5469 directory) can be applied to gcc to fix the problem. Alternatively, if you
5470 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5471 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5472 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5475 * New 'maintenance' command
5477 All of the commands related to hacking GDB internals have been moved out of
5478 the main command set, and now live behind the 'maintenance' command. This
5479 can also be abbreviated as 'mt'. The following changes were made:
5481 dump-me -> maintenance dump-me
5482 info all-breakpoints -> maintenance info breakpoints
5483 printmsyms -> maintenance print msyms
5484 printobjfiles -> maintenance print objfiles
5485 printpsyms -> maintenance print psymbols
5486 printsyms -> maintenance print symbols
5488 The following commands are new:
5490 maintenance demangle Call internal GDB demangler routine to
5491 demangle a C++ link name and prints the result.
5492 maintenance print type Print a type chain for a given symbol
5494 * Change to .gdbinit file processing
5496 We now read the $HOME/.gdbinit file before processing the argv arguments
5497 (e.g. reading symbol files or core files). This allows global parameters to
5498 be set, which will apply during the symbol reading. The ./.gdbinit is still
5499 read after argv processing.
5501 * New hosts supported
5503 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5505 GNU/Linux support i386-unknown-linux or linux
5507 We are also including code to support the HP/PA running BSD and HPUX. This
5508 is almost guaranteed not to work, as we didn't have time to test or build it
5509 for this release. We are including it so that the more adventurous (or
5510 masochistic) of you can play with it. We also had major problems with the
5511 fact that the compiler that we got from HP doesn't support the -g option.
5514 * New targets supported
5516 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5518 * More smarts about finding #include files
5520 GDB now remembers the compilation directory for all include files, and for
5521 all files from which C is generated (like yacc and lex sources). This
5522 greatly improves GDB's ability to find yacc/lex sources, and include files,
5523 especially if you are debugging your program from a directory different from
5524 the one that contains your sources.
5526 We also fixed a bug which caused difficulty with listing and setting
5527 breakpoints in include files which contain C code. (In the past, you had to
5528 try twice in order to list an include file that you hadn't looked at before.)
5530 * Interesting infernals change
5532 GDB now deals with arbitrary numbers of sections, where the symbols for each
5533 section must be relocated relative to that section's landing place in the
5534 target's address space. This work was needed to support ELF with embedded
5535 stabs used by Solaris-2.0.
5537 * Bug fixes (of course!)
5539 There have been loads of fixes for the following things:
5540 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5541 i960, stabs, DOS(GO32), procfs, etc...
5543 See the ChangeLog for details.
5545 *** Changes in GDB-4.5:
5547 * New machines supported (host and target)
5549 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5551 SGI Irix-4.x mips-sgi-irix4 or iris4
5553 * New malloc package
5555 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5556 Mmalloc is capable of handling mutiple heaps of memory. It is also
5557 capable of saving a heap to a file, and then mapping it back in later.
5558 This can be used to greatly speedup the startup of GDB by using a
5559 pre-parsed symbol table which lives in a mmalloc managed heap. For
5560 more details, please read mmalloc/mmalloc.texi.
5564 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5565 'help info proc' for details.
5567 * MIPS ecoff symbol table format
5569 The code that reads MIPS symbol table format is now supported on all hosts.
5570 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5573 * File name changes for MS-DOS
5575 Many files in the config directories have been renamed to make it easier to
5576 support GDB on MS-DOSe systems (which have very restrictive file name
5577 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5578 environment) is close to working but has some remaining problems. Note
5579 that debugging of DOS programs is not supported, due to limitations
5580 in the ``operating system'', but it can be used to host cross-debugging.
5582 * Cross byte order fixes
5584 Many fixes have been made to support cross debugging of Sparc and MIPS
5585 targets from hosts whose byte order differs.
5587 * New -mapped and -readnow options
5589 If memory-mapped files are available on your system through the 'mmap'
5590 system call, you can use the -mapped option on the `file' or
5591 `symbol-file' commands to cause GDB to write the symbols from your
5592 program into a reusable file. If the program you are debugging is
5593 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5594 Future GDB debugging sessions will notice the presence of this file,
5595 and will quickly map in symbol information from it, rather than reading
5596 the symbol table from the executable program. Using the '-mapped'
5597 option in a GDB `file' or `symbol-file' command has the same effect as
5598 starting GDB with the '-mapped' command-line option.
5600 You can cause GDB to read the entire symbol table immediately by using
5601 the '-readnow' option with any of the commands that load symbol table
5602 information (or on the GDB command line). This makes the command
5603 slower, but makes future operations faster.
5605 The -mapped and -readnow options are typically combined in order to
5606 build a `fred.syms' file that contains complete symbol information.
5607 A simple GDB invocation to do nothing but build a `.syms' file for future
5610 gdb -batch -nx -mapped -readnow programname
5612 The `.syms' file is specific to the host machine on which GDB is run.
5613 It holds an exact image of GDB's internal symbol table. It cannot be
5614 shared across multiple host platforms.
5616 * longjmp() handling
5618 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5619 siglongjmp() without losing control. This feature has not yet been ported to
5620 all systems. It currently works on many 386 platforms, all MIPS-based
5621 platforms (SGI, DECstation, etc), and Sun3/4.
5625 Preliminary work has been put in to support the new Solaris OS from Sun. At
5626 this time, it can control and debug processes, but it is not capable of
5631 As always, many many bug fixes. The major areas were with g++, and mipsread.
5632 People using the MIPS-based platforms should experience fewer mysterious
5633 crashes and trashed symbol tables.
5635 *** Changes in GDB-4.4:
5637 * New machines supported (host and target)
5639 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5641 BSD Reno on Vax vax-dec-bsd
5642 Ultrix on Vax vax-dec-ultrix
5644 * New machines supported (target)
5646 AMD 29000 embedded, using EBMON a29k-none-none
5650 GDB continues to improve its handling of C++. `References' work better.
5651 The demangler has also been improved, and now deals with symbols mangled as
5652 per the Annotated C++ Reference Guide.
5654 GDB also now handles `stabs' symbol information embedded in MIPS
5655 `ecoff' symbol tables. Since the ecoff format was not easily
5656 extensible to handle new languages such as C++, this appeared to be a
5657 good way to put C++ debugging info into MIPS binaries. This option
5658 will be supported in the GNU C compiler, version 2, when it is
5661 * New features for SVR4
5663 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5664 shared libraries. Debugging dynamically linked programs should present
5665 only minor differences from debugging statically linked programs.
5667 The `info proc' command will print out information about any process
5668 on an SVR4 system (including the one you are debugging). At the moment,
5669 it prints the address mappings of the process.
5671 If you bring up GDB on another SVR4 system, please send mail to
5672 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5674 * Better dynamic linking support in SunOS
5676 Reading symbols from shared libraries which contain debugging symbols
5677 now works properly. However, there remain issues such as automatic
5678 skipping of `transfer vector' code during function calls, which
5679 make it harder to debug code in a shared library, than to debug the
5680 same code linked statically.
5684 GDB is now using the latest `getopt' routines from the FSF. This
5685 version accepts the -- prefix for options with long names. GDB will
5686 continue to accept the old forms (-option and +option) as well.
5687 Various single letter abbreviations for options have been explicity
5688 added to the option table so that they won't get overshadowed in the
5689 future by other options that begin with the same letter.
5693 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5694 Many assorted bugs have been handled. Many more remain to be handled.
5695 See the various ChangeLog files (primarily in gdb and bfd) for details.
5698 *** Changes in GDB-4.3:
5700 * New machines supported (host and target)
5702 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5703 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5704 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5706 * Almost SCO Unix support
5708 We had hoped to support:
5709 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5710 (except for core file support), but we discovered very late in the release
5711 that it has problems with process groups that render gdb unusable. Sorry
5712 about that. I encourage people to fix it and post the fixes.
5714 * Preliminary ELF and DWARF support
5716 GDB can read ELF object files on System V Release 4, and can handle
5717 debugging records for C, in DWARF format, in ELF files. This support
5718 is preliminary. If you bring up GDB on another SVR4 system, please
5719 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5724 GDB now uses the latest `readline' library. One user-visible change
5725 is that two tabs will list possible command completions, which previously
5726 required typing M-? (meta-question mark, or ESC ?).
5730 The `stepi' bug that many of you noticed has been squashed.
5731 Many bugs in C++ have been handled. Many more remain to be handled.
5732 See the various ChangeLog files (primarily in gdb and bfd) for details.
5734 * State of the MIPS world (in case you wondered):
5736 GDB can understand the symbol tables emitted by the compilers
5737 supplied by most vendors of MIPS-based machines, including DEC. These
5738 symbol tables are in a format that essentially nobody else uses.
5740 Some versions of gcc come with an assembler post-processor called
5741 mips-tfile. This program is required if you want to do source-level
5742 debugging of gcc-compiled programs. I believe FSF does not ship
5743 mips-tfile with gcc version 1, but it will eventually come with gcc
5746 Debugging of g++ output remains a problem. g++ version 1.xx does not
5747 really support it at all. (If you're lucky, you should be able to get
5748 line numbers and stack traces to work, but no parameters or local
5749 variables.) With some work it should be possible to improve the
5752 When gcc version 2 is released, you will have somewhat better luck.
5753 However, even then you will get confusing results for inheritance and
5756 We will eventually provide full debugging of g++ output on
5757 DECstations. This will probably involve some kind of stabs-in-ecoff
5758 encapulation, but the details have not been worked out yet.
5761 *** Changes in GDB-4.2:
5763 * Improved configuration
5765 Only one copy of `configure' exists now, and it is not self-modifying.
5766 Porting BFD is simpler.
5770 The `step' and `next' commands now only stop at the first instruction
5771 of a source line. This prevents the multiple stops that used to occur
5772 in switch statements, for-loops, etc. `Step' continues to stop if a
5773 function that has debugging information is called within the line.
5777 Lots of small bugs fixed. More remain.
5779 * New host supported (not target)
5781 Intel 386 PC clone running Mach i386-none-mach
5784 *** Changes in GDB-4.1:
5786 * Multiple source language support
5788 GDB now has internal scaffolding to handle several source languages.
5789 It determines the type of each source file from its filename extension,
5790 and will switch expression parsing and number formatting to match the
5791 language of the function in the currently selected stack frame.
5792 You can also specifically set the language to be used, with
5793 `set language c' or `set language modula-2'.
5797 GDB now has preliminary support for the GNU Modula-2 compiler,
5798 currently under development at the State University of New York at
5799 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5800 continue through the fall of 1991 and into 1992.
5802 Other Modula-2 compilers are currently not supported, and attempting to
5803 debug programs compiled with them will likely result in an error as the
5804 symbol table is read. Feel free to work on it, though!
5806 There are hooks in GDB for strict type checking and range checking,
5807 in the `Modula-2 philosophy', but they do not currently work.
5811 GDB can now write to executable and core files (e.g. patch
5812 a variable's value). You must turn this switch on, specify
5813 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5814 by assigning a new value to a variable. Modifications take
5817 * Automatic SunOS shared library reading
5819 When you run your program, GDB automatically determines where its
5820 shared libraries (if any) have been loaded, and reads their symbols.
5821 The `share' command is no longer needed. This also works when
5822 examining core files.
5826 You can specify the number of lines that the `list' command shows.
5829 * New machines supported (host and target)
5831 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5832 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5833 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5835 * New hosts supported (not targets)
5837 IBM RT/PC: romp-ibm-aix or rtpc
5839 * New targets supported (not hosts)
5841 AMD 29000 embedded with COFF a29k-none-coff
5842 AMD 29000 embedded with a.out a29k-none-aout
5843 Ultracomputer remote kernel debug a29k-nyu-kern
5845 * New remote interfaces
5851 *** Changes in GDB-4.0:
5855 Wide output is wrapped at good places to make the output more readable.
5857 Gdb now supports cross-debugging from a host machine of one type to a
5858 target machine of another type. Communication with the target system
5859 is over serial lines. The ``target'' command handles connecting to the
5860 remote system; the ``load'' command will download a program into the
5861 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5862 also supports debugging of realtime processes running under VxWorks,
5863 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5864 stub on the target system.
5866 New CPUs supported include the AMD 29000 and Intel 960.
5868 GDB now reads object files and symbol tables via a ``binary file''
5869 library, which allows a single copy of GDB to debug programs of multiple
5870 object file types such as a.out and coff.
5872 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5873 refcard.dvi and refcard.ps are available to format it).
5876 * Control-Variable user interface simplified
5878 All variables that control the operation of the debugger can be set
5879 by the ``set'' command, and displayed by the ``show'' command.
5881 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5882 ``Show prompt'' produces the response:
5883 Gdb's prompt is new-gdb=>.
5885 What follows are the NEW set commands. The command ``help set'' will
5886 print a complete list of old and new set commands. ``help set FOO''
5887 will give a longer description of the variable FOO. ``show'' will show
5888 all of the variable descriptions and their current settings.
5890 confirm on/off: Enables warning questions for operations that are
5891 hard to recover from, e.g. rerunning the program while
5892 it is already running. Default is ON.
5894 editing on/off: Enables EMACS style command line editing
5895 of input. Previous lines can be recalled with
5896 control-P, the current line can be edited with control-B,
5897 you can search for commands with control-R, etc.
5900 history filename NAME: NAME is where the gdb command history
5901 will be stored. The default is .gdb_history,
5902 or the value of the environment variable
5905 history size N: The size, in commands, of the command history. The
5906 default is 256, or the value of the environment variable
5909 history save on/off: If this value is set to ON, the history file will
5910 be saved after exiting gdb. If set to OFF, the
5911 file will not be saved. The default is OFF.
5913 history expansion on/off: If this value is set to ON, then csh-like
5914 history expansion will be performed on
5915 command line input. The default is OFF.
5917 radix N: Sets the default radix for input and output. It can be set
5918 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5919 in the current radix, so "set radix 10" is always a no-op.
5921 height N: This integer value is the number of lines on a page. Default
5922 is 24, the current `stty rows'' setting, or the ``li#''
5923 setting from the termcap entry matching the environment
5926 width N: This integer value is the number of characters on a line.
5927 Default is 80, the current `stty cols'' setting, or the ``co#''
5928 setting from the termcap entry matching the environment
5931 Note: ``set screensize'' is obsolete. Use ``set height'' and
5932 ``set width'' instead.
5934 print address on/off: Print memory addresses in various command displays,
5935 such as stack traces and structure values. Gdb looks
5936 more ``symbolic'' if you turn this off; it looks more
5937 ``machine level'' with it on. Default is ON.
5939 print array on/off: Prettyprint arrays. New convenient format! Default
5942 print demangle on/off: Print C++ symbols in "source" form if on,
5945 print asm-demangle on/off: Same, for assembler level printouts
5948 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5951 * Support for Epoch Environment.
5953 The epoch environment is a version of Emacs v18 with windowing. One
5954 new command, ``inspect'', is identical to ``print'', except that if you
5955 are running in the epoch environment, the value is printed in its own
5959 * Support for Shared Libraries
5961 GDB can now debug programs and core files that use SunOS shared libraries.
5962 Symbols from a shared library cannot be referenced
5963 before the shared library has been linked with the program (this
5964 happens after you type ``run'' and before the function main() is entered).
5965 At any time after this linking (including when examining core files
5966 from dynamically linked programs), gdb reads the symbols from each
5967 shared library when you type the ``sharedlibrary'' command.
5968 It can be abbreviated ``share''.
5970 sharedlibrary REGEXP: Load shared object library symbols for files
5971 matching a unix regular expression. No argument
5972 indicates to load symbols for all shared libraries.
5974 info sharedlibrary: Status of loaded shared libraries.
5979 A watchpoint stops execution of a program whenever the value of an
5980 expression changes. Checking for this slows down execution
5981 tremendously whenever you are in the scope of the expression, but is
5982 quite useful for catching tough ``bit-spreader'' or pointer misuse
5983 problems. Some machines such as the 386 have hardware for doing this
5984 more quickly, and future versions of gdb will use this hardware.
5986 watch EXP: Set a watchpoint (breakpoint) for an expression.
5988 info watchpoints: Information about your watchpoints.
5990 delete N: Deletes watchpoint number N (same as breakpoints).
5991 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5992 enable N: Re-enables watchpoint number N (same as breakpoints).
5995 * C++ multiple inheritance
5997 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6000 * C++ exception handling
6002 Gdb now supports limited C++ exception handling. Besides the existing
6003 ability to breakpoint on an exception handler, gdb can breakpoint on
6004 the raising of an exception (before the stack is peeled back to the
6007 catch FOO: If there is a FOO exception handler in the dynamic scope,
6008 set a breakpoint to catch exceptions which may be raised there.
6009 Multiple exceptions (``catch foo bar baz'') may be caught.
6011 info catch: Lists all exceptions which may be caught in the
6012 current stack frame.
6015 * Minor command changes
6017 The command ``call func (arg, arg, ...)'' now acts like the print
6018 command, except it does not print or save a value if the function's result
6019 is void. This is similar to dbx usage.
6021 The ``up'' and ``down'' commands now always print the frame they end up
6022 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6023 frames without printing.
6025 * New directory command
6027 'dir' now adds directories to the FRONT of the source search path.
6028 The path starts off empty. Source files that contain debug information
6029 about the directory in which they were compiled can be found even
6030 with an empty path; Sun CC and GCC include this information. If GDB can't
6031 find your source file in the current directory, type "dir .".
6033 * Configuring GDB for compilation
6035 For normal use, type ``./configure host''. See README or gdb.texinfo
6038 GDB now handles cross debugging. If you are remotely debugging between
6039 two different machines, type ``./configure host -target=targ''.
6040 Host is the machine where GDB will run; targ is the machine
6041 where the program that you are debugging will run.
projects / external / binutils.git / blob