1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.10
6 * Record btrace now supports non-stop mode.
8 * Support for tracepoints on aarch64-linux was added in GDBserver.
10 * The 'record instruction-history' command now indicates speculative execution
11 when using the Intel(R) Processor Trace recording format.
13 * GDB now allows users to specify explicit locations, bypassing
14 the linespec parser. This feature is also available to GDB/MI
17 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
18 GDB now is able to debug both AArch64 applications and ARM applications
21 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
22 including JIT compiling fast tracepoint's conditional expression bytecode
25 * GDB now supports displaced stepping on AArch64 GNU/Linux.
27 * "info threads", "info inferiors", "info display", "info checkpoints"
28 and "maint info program-spaces" now list the corresponding items in
29 ascending ID order, for consistency with all other "info" commands.
33 maint set target-non-stop (on|off|auto)
34 maint show target-non-stop
35 Control whether GDB targets always operate in non-stop mode even if
36 "set non-stop" is "off". The default is "auto", meaning non-stop
37 mode is enabled if supported by the target.
40 maint show bfd-sharing
41 Control the reuse of bfd objects.
45 Control display of debugging info regarding bfd caching.
47 set remote multiprocess-extensions-packet
48 show remote multiprocess-extensions-packet
49 Set/show the use of the remote protocol multiprocess extensions.
51 * The "disassemble" command accepts a new modifier: /s.
52 It prints mixed source+disassembly like /m with two differences:
53 - disassembled instructions are now printed in program order, and
54 - and source for all relevant files is now printed.
55 The "/m" option is now considered deprecated: its "source-centric"
56 output hasn't proved useful in practice.
58 * The "record instruction-history" command accepts a new modifier: /s.
59 It behaves exactly like /m and prints mixed source+disassembly.
61 * The "set scheduler-locking" command supports a new mode "replay".
62 It behaves like "off" in record mode and like "on" in replay mode.
64 * Support for various ROM monitors has been removed:
66 target dbug dBUG ROM monitor for Motorola ColdFire
67 target picobug Motorola picobug monitor
68 target dink32 DINK32 ROM monitor for PowerPC
69 target m32r Renesas M32R/D ROM monitor
70 target mon2000 mon2000 ROM monitor
71 target ppcbug PPCBUG ROM monitor for PowerPC
73 * Support for reading/writing memory and extracting values on architectures
74 whose memory is addressable in units of any integral multiple of 8 bits.
79 Indicates that an exec system call was executed.
81 exec-events feature in qSupported
82 The qSupported packet allows GDB to request support for exec
83 events using the new 'gdbfeature' exec-event, and the qSupported
84 response can contain the corresponding 'stubfeature'. Set and
85 show commands can be used to display whether these features are enabled.
87 * Extended-remote exec events
89 ** GDB now has support for exec events on extended-remote Linux targets.
90 For such targets with Linux kernels 2.5.46 and later, this enables
91 follow-exec-mode and exec catchpoints.
93 set remote exec-event-feature-packet
94 show remote exec-event-feature-packet
95 Set/show the use of the remote exec event feature.
97 *** Changes in GDB 7.10
99 * Support for process record-replay and reverse debugging on aarch64*-linux*
100 targets has been added. GDB now supports recording of A64 instruction set
101 including advance SIMD instructions.
103 * Support for Sun's version of the "stabs" debug file format has been removed.
105 * GDB now honors the content of the file /proc/PID/coredump_filter
106 (PID is the process ID) on GNU/Linux systems. This file can be used
107 to specify the types of memory mappings that will be included in a
108 corefile. For more information, please refer to the manual page of
109 "core(5)". GDB also has a new command: "set use-coredump-filter
110 on|off". It allows to set whether GDB will read the content of the
111 /proc/PID/coredump_filter file when generating a corefile.
113 * The "info os" command on GNU/Linux can now display information on
115 "info os cpus" Listing of all cpus/cores on the system
117 * GDB has two new commands: "set serial parity odd|even|none" and
118 "show serial parity". These allows to set or show parity for the
121 * The "info source" command now displays the producer string if it was
122 present in the debug info. This typically includes the compiler version
123 and may include things like its command line arguments.
125 * The "info dll", an alias of the "info sharedlibrary" command,
126 is now available on all platforms.
128 * Directory names supplied to the "set sysroot" commands may be
129 prefixed with "target:" to tell GDB to access shared libraries from
130 the target system, be it local or remote. This replaces the prefix
131 "remote:". The default sysroot has been changed from "" to
132 "target:". "remote:" is automatically converted to "target:" for
133 backward compatibility.
135 * The system root specified by "set sysroot" will be prepended to the
136 filename of the main executable (if reported to GDB as absolute by
137 the operating system) when starting processes remotely, and when
138 attaching to already-running local or remote processes.
140 * GDB now supports automatic location and retrieval of executable
141 files from remote targets. Remote debugging can now be initiated
142 using only a "target remote" or "target extended-remote" command
143 (no "set sysroot" or "file" commands are required). See "New remote
146 * The "dump" command now supports verilog hex format.
148 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
150 * On GNU/Linux, GDB and gdbserver are now able to access executable
151 and shared library files without a "set sysroot" command when
152 attaching to processes running in different mount namespaces from
153 the debugger. This makes it possible to attach to processes in
154 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
155 See "New remote packets" below.
157 * The "tui reg" command now provides completion for all of the
158 available register groups, including target specific groups.
160 * The HISTSIZE environment variable is no longer read when determining
161 the size of GDB's command history. GDB now instead reads the dedicated
162 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
163 disables truncation of command history. Non-numeric values of GDBHISTSIZE
168 ** Memory ports can now be unbuffered.
172 ** gdb.Objfile objects have a new attribute "username",
173 which is the name of the objfile as specified by the user,
174 without, for example, resolving symlinks.
175 ** You can now write frame unwinders in Python.
176 ** gdb.Type objects have a new method "optimized_out",
177 returning optimized out gdb.Value instance of this type.
178 ** gdb.Value objects have new methods "reference_value" and
179 "const_value" which return a reference to the value and a
180 "const" version of the value respectively.
184 maint print symbol-cache
185 Print the contents of the symbol cache.
187 maint print symbol-cache-statistics
188 Print statistics of symbol cache usage.
190 maint flush-symbol-cache
191 Flush the contents of the symbol cache.
195 Start branch trace recording using Branch Trace Store (BTS) format.
198 Evaluate expression by using the compiler and print result.
202 Explicit commands for enabling and disabling tui mode.
205 set mpx bound on i386 and amd64
206 Support for bound table investigation on Intel(R) MPX enabled applications.
210 Start branch trace recording using Intel(R) Processor Trace format.
213 Print information about branch tracing internals.
215 maint btrace packet-history
216 Print the raw branch tracing data.
218 maint btrace clear-packet-history
219 Discard the stored raw branch tracing data.
222 Discard all branch tracing data. It will be fetched and processed
223 anew by the next "record" command.
228 Renamed from "set debug dwarf2-die".
230 Renamed from "show debug dwarf2-die".
233 Renamed from "set debug dwarf2-read".
234 show debug dwarf-read
235 Renamed from "show debug dwarf2-read".
237 maint set dwarf always-disassemble
238 Renamed from "maint set dwarf2 always-disassemble".
239 maint show dwarf always-disassemble
240 Renamed from "maint show dwarf2 always-disassemble".
242 maint set dwarf max-cache-age
243 Renamed from "maint set dwarf2 max-cache-age".
244 maint show dwarf max-cache-age
245 Renamed from "maint show dwarf2 max-cache-age".
248 show debug dwarf-line
249 Control display of debugging info regarding DWARF line processing.
253 Set the maximum number of candidates to be considered during
254 completion. The default value is 200. This limit allows GDB
255 to avoid generating large completion lists, the computation of
256 which can cause the debugger to become temporarily unresponsive.
258 set history remove-duplicates
259 show history remove-duplicates
260 Control the removal of duplicate history entries.
262 maint set symbol-cache-size
263 maint show symbol-cache-size
264 Control the size of the symbol cache.
266 set|show record btrace bts buffer-size
267 Set and show the size of the ring buffer used for branch tracing in
269 The obtained size may differ from the requested size. Use "info
270 record" to see the obtained buffer size.
272 set debug linux-namespaces
273 show debug linux-namespaces
274 Control display of debugging info regarding Linux namespaces.
276 set|show record btrace pt buffer-size
277 Set and show the size of the ring buffer used for branch tracing in
278 Intel(R) Processor Trace format.
279 The obtained size may differ from the requested size. Use "info
280 record" to see the obtained buffer size.
282 maint set|show btrace pt skip-pad
283 Set and show whether PAD packets are skipped when computing the
286 * The command 'thread apply all' can now support new option '-ascending'
287 to call its specified command for all threads in ascending order.
289 * Python/Guile scripting
291 ** GDB now supports auto-loading of Python/Guile scripts contained in the
292 special section named `.debug_gdb_scripts'.
296 qXfer:btrace-conf:read
297 Return the branch trace configuration for the current thread.
299 Qbtrace-conf:bts:size
300 Set the requested ring buffer size for branch tracing in BTS format.
303 Enable Intel(R) Procesor Trace-based branch tracing for the current
304 process. The remote stub reports support for this packet to GDB's
308 Set the requested ring buffer size for branch tracing in Intel(R) Processor
312 Indicates a memory breakpoint instruction was executed, irrespective
313 of whether it was GDB that planted the breakpoint or the breakpoint
314 is hardcoded in the program. This is required for correct non-stop
318 Indicates the target stopped for a hardware breakpoint. This is
319 required for correct non-stop mode operation.
322 Return information about files on the remote system.
325 Return the full absolute name of the file that was executed to
326 create a process running on the remote system.
329 Select the filesystem on which vFile: operations with filename
330 arguments will operate. This is required for GDB to be able to
331 access files on remote targets where the remote stub does not
332 share a common filesystem with the inferior(s).
335 Indicates that a fork system call was executed.
338 Indicates that a vfork system call was executed.
340 vforkdone stop reason
341 Indicates that a vfork child of the specified process has executed
342 an exec or exit, allowing the vfork parent to resume execution.
344 fork-events and vfork-events features in qSupported
345 The qSupported packet allows GDB to request support for fork and
346 vfork events using new 'gdbfeatures' fork-events and vfork-events,
347 and the qSupported response can contain the corresponding
348 'stubfeatures'. Set and show commands can be used to display
349 whether these features are enabled.
351 * Extended-remote fork events
353 ** GDB now has support for fork events on extended-remote Linux
354 targets. For targets with Linux kernels 2.5.60 and later, this
355 enables follow-fork-mode and detach-on-fork for both fork and
356 vfork, as well as fork and vfork catchpoints.
358 * The info record command now shows the recording format and the
359 branch tracing configuration for the current thread when using
360 the btrace record target.
361 For the BTS format, it shows the ring buffer size.
363 * GDB now has support for DTrace USDT (Userland Static Defined
364 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
366 * GDB now supports access to vector registers on S/390 GNU/Linux
369 * Removed command line options
371 -xdb HP-UX XDB compatibility mode.
373 * Removed targets and native configurations
375 HP/PA running HP-UX hppa*-*-hpux*
376 Itanium running HP-UX ia64-*-hpux*
378 * New configure options
381 This configure option allows the user to build GDB with support for
382 Intel(R) Processor Trace (default: auto). This requires libipt.
384 --with-libipt-prefix=PATH
385 Specify the path to the version of libipt that GDB should use.
386 $PATH/include should contain the intel-pt.h header and
387 $PATH/lib should contain the libipt.so library.
389 *** Changes in GDB 7.9.1
393 ** Xmethods can now specify a result type.
395 *** Changes in GDB 7.9
397 * GDB now supports hardware watchpoints on x86 GNU Hurd.
401 ** You can now access frame registers from Python scripts.
402 ** New attribute 'producer' for gdb.Symtab objects.
403 ** gdb.Objfile objects have a new attribute "progspace",
404 which is the gdb.Progspace object of the containing program space.
405 ** gdb.Objfile objects have a new attribute "owner".
406 ** gdb.Objfile objects have a new attribute "build_id",
407 which is the build ID generated when the file was built.
408 ** gdb.Objfile objects have a new method "add_separate_debug_file".
409 ** A new event "gdb.clear_objfiles" has been added, triggered when
410 selecting a new file to debug.
411 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
412 ** New function gdb.lookup_objfile.
414 New events which are triggered when GDB modifies the state of the
417 ** gdb.events.inferior_call_pre: Function call is about to be made.
418 ** gdb.events.inferior_call_post: Function call has just been made.
419 ** gdb.events.memory_changed: A memory location has been altered.
420 ** gdb.events.register_changed: A register has been altered.
422 * New Python-based convenience functions:
424 ** $_caller_is(name [, number_of_frames])
425 ** $_caller_matches(regexp [, number_of_frames])
426 ** $_any_caller_is(name [, number_of_frames])
427 ** $_any_caller_matches(regexp [, number_of_frames])
429 * GDB now supports the compilation and injection of source code into
430 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
431 to compile the source code to object code, and if successful, inject
432 and execute that code within the current context of the inferior.
433 Currently the C language is supported. The commands used to
434 interface with this new feature are:
436 compile code [-raw|-r] [--] [source code]
437 compile file [-raw|-r] filename
441 demangle [-l language] [--] name
442 Demangle "name" in the specified language, or the current language
443 if elided. This command is renamed from the "maint demangle" command.
444 The latter is kept as a no-op to avoid "maint demangle" being interpreted
445 as "maint demangler-warning".
447 queue-signal signal-name-or-number
448 Queue a signal to be delivered to the thread when it is resumed.
450 add-auto-load-scripts-directory directory
451 Add entries to the list of directories from which to load auto-loaded
454 maint print user-registers
455 List all currently available "user" registers.
457 compile code [-r|-raw] [--] [source code]
458 Compile, inject, and execute in the inferior the executable object
459 code produced by compiling the provided source code.
461 compile file [-r|-raw] filename
462 Compile and inject into the inferior the executable object code
463 produced by compiling the source code stored in the filename
466 * On resume, GDB now always passes the signal the program had stopped
467 for to the thread the signal was sent to, even if the user changed
468 threads before resuming. Previously GDB would often (but not
469 always) deliver the signal to the thread that happens to be current
472 * Conversely, the "signal" command now consistently delivers the
473 requested signal to the current thread. GDB now asks for
474 confirmation if the program had stopped for a signal and the user
475 switched threads meanwhile.
477 * "breakpoint always-inserted" modes "off" and "auto" merged.
479 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
480 won't remove breakpoints from the target until all threads stop,
481 even in non-stop mode. The "auto" mode has been removed, and "off"
482 is now the default mode.
486 set debug symbol-lookup
487 show debug symbol-lookup
488 Control display of debugging info regarding symbol lookup.
492 ** The -list-thread-groups command outputs an exit-code field for
493 inferiors that have exited.
497 MIPS SDE mips*-sde*-elf*
501 Support for these obsolete configurations has been removed.
503 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
504 SGI Irix-5.x mips-*-irix5*
505 SGI Irix-6.x mips-*-irix6*
506 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
507 VAX running Ultrix vax-*-ultrix*
509 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
510 and "assf"), have been removed. Use the "sharedlibrary" command, or
511 its alias "share", instead.
513 *** Changes in GDB 7.8
515 * New command line options
518 This is an alias for the --data-directory option.
520 * GDB supports printing and modifying of variable length automatic arrays
521 as specified in ISO C99.
523 * The ARM simulator now supports instruction level tracing
524 with or without disassembly.
528 GDB now has support for scripting using Guile. Whether this is
529 available is determined at configure time.
530 Guile version 2.0 or greater is required.
531 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
533 * New commands (for set/show, see "New options" below)
537 Invoke CODE by passing it to the Guile interpreter.
541 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
543 info auto-load guile-scripts [regexp]
544 Print the list of automatically loaded Guile scripts.
546 * The source command is now capable of sourcing Guile scripts.
547 This feature is dependent on the debugger being built with Guile support.
551 set print symbol-loading (off|brief|full)
552 show print symbol-loading
553 Control whether to print informational messages when loading symbol
554 information for a file. The default is "full", but when debugging
555 programs with large numbers of shared libraries the amount of output
558 set guile print-stack (none|message|full)
559 show guile print-stack
560 Show a stack trace when an error is encountered in a Guile script.
562 set auto-load guile-scripts (on|off)
563 show auto-load guile-scripts
564 Control auto-loading of Guile script files.
566 maint ada set ignore-descriptive-types (on|off)
567 maint ada show ignore-descriptive-types
568 Control whether the debugger should ignore descriptive types in Ada
569 programs. The default is not to ignore the descriptive types. See
570 the user manual for more details on descriptive types and the intended
571 usage of this option.
573 set auto-connect-native-target
575 Control whether GDB is allowed to automatically connect to the
576 native target for the run, attach, etc. commands when not connected
577 to any target yet. See also "target native" below.
579 set record btrace replay-memory-access (read-only|read-write)
580 show record btrace replay-memory-access
581 Control what memory accesses are allowed during replay.
583 maint set target-async (on|off)
584 maint show target-async
585 This controls whether GDB targets operate in synchronous or
586 asynchronous mode. Normally the default is asynchronous, if it is
587 available; but this can be changed to more easily debug problems
588 occurring only in synchronous mode.
590 set mi-async (on|off)
592 Control whether MI asynchronous mode is preferred. This supersedes
593 "set target-async" of previous GDB versions.
595 * "set target-async" is deprecated as a CLI option and is now an alias
596 for "set mi-async" (only puts MI into async mode).
598 * Background execution commands (e.g., "c&", "s&", etc.) are now
599 possible ``out of the box'' if the target supports them. Previously
600 the user would need to explicitly enable the possibility with the
601 "set target-async on" command.
603 * New features in the GDB remote stub, GDBserver
605 ** New option --debug-format=option1[,option2,...] allows one to add
606 additional text to each output. At present only timestamps
607 are supported: --debug-format=timestamps.
608 Timestamps can also be turned on with the
609 "monitor set debug-format timestamps" command from GDB.
611 * The 'record instruction-history' command now starts counting instructions
612 at one. This also affects the instruction ranges reported by the
613 'record function-call-history' command when given the /i modifier.
615 * The command 'record function-call-history' supports a new modifier '/c' to
616 indent the function names based on their call stack depth.
617 The fields for the '/i' and '/l' modifier have been reordered.
618 The source line range is now prefixed with 'at'.
619 The instruction range is now prefixed with 'inst'.
620 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
621 "record instruction-history" and "list" commands.
623 * The ranges given as arguments to the 'record function-call-history' and
624 'record instruction-history' commands are now inclusive.
626 * The btrace record target now supports the 'record goto' command.
627 For locations inside the execution trace, the back trace is computed
628 based on the information stored in the execution trace.
630 * The btrace record target supports limited reverse execution and replay.
631 The target does not record data and therefore does not allow reading
634 * The "catch syscall" command now works on s390*-linux* targets.
636 * The "compare-sections" command is no longer specific to target
637 remote. It now works with all targets.
639 * All native targets are now consistently called "native".
640 Consequently, the "target child", "target GNU", "target djgpp",
641 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
642 commands have been replaced with "target native". The QNX/NTO port
643 leaves the "procfs" target in place and adds a "native" target for
644 consistency with other ports. The impact on users should be minimal
645 as these commands previously either throwed an error, or were
646 no-ops. The target's name is visible in the output of the following
647 commands: "help target", "info target", "info files", "maint print
650 * The "target native" command now connects to the native target. This
651 can be used to launch native programs even when "set
652 auto-connect-native-target" is set to off.
654 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
656 * Support for Intel(R) AVX-512 registers on GNU/Linux.
657 Support displaying and modifying Intel(R) AVX-512 registers
658 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
662 qXfer:btrace:read's annex
663 The qXfer:btrace:read packet supports a new annex 'delta' to read
664 branch trace incrementally.
668 ** Valid Python operations on gdb.Value objects representing
669 structs/classes invoke the corresponding overloaded operators if
671 ** New `Xmethods' feature in the Python API. Xmethods are
672 additional methods or replacements for existing methods of a C++
673 class. This feature is useful for those cases where a method
674 defined in C++ source code could be inlined or optimized out by
675 the compiler, making it unavailable to GDB.
678 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
680 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
681 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
682 its alias "share", instead.
684 * The commands "set remotebaud" and "show remotebaud" are no longer
685 supported. Use "set serial baud" and "show serial baud" (respectively)
690 ** A new option "-gdb-set mi-async" replaces "-gdb-set
691 target-async". The latter is left as a deprecated alias of the
692 former for backward compatibility. If the target supports it,
693 CLI background execution commands are now always possible by
694 default, independently of whether the frontend stated a
695 preference for asynchronous execution with "-gdb-set mi-async".
696 Previously "-gdb-set target-async off" affected both MI execution
697 commands and CLI execution commands.
699 *** Changes in GDB 7.7
701 * Improved support for process record-replay and reverse debugging on
702 arm*-linux* targets. Support for thumb32 and syscall instruction
703 recording has been added.
705 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
707 * GDB now supports Fission DWP file format version 2.
708 http://gcc.gnu.org/wiki/DebugFission
710 * New convenience function "$_isvoid", to check whether an expression
711 is void. A void expression is an expression where the type of the
712 result is "void". For example, some convenience variables may be
713 "void" when evaluated (e.g., "$_exitcode" before the execution of
714 the program being debugged; or an undefined convenience variable).
715 Another example, when calling a function whose return type is
718 * The "maintenance print objfiles" command now takes an optional regexp.
720 * The "catch syscall" command now works on arm*-linux* targets.
722 * GDB now consistently shows "<not saved>" when printing values of
723 registers the debug info indicates have not been saved in the frame
724 and there's nowhere to retrieve them from
725 (callee-saved/call-clobbered registers):
730 (gdb) info registers rax
733 Before, the former would print "<optimized out>", and the latter
734 "*value not available*".
736 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
741 ** Frame filters and frame decorators have been added.
742 ** Temporary breakpoints are now supported.
743 ** Line tables representation has been added.
744 ** New attribute 'parent_type' for gdb.Field objects.
745 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
746 ** New attribute 'name' for gdb.Type objects.
750 Nios II ELF nios2*-*-elf
751 Nios II GNU/Linux nios2*-*-linux
752 Texas Instruments MSP430 msp430*-*-elf
754 * Removed native configurations
756 Support for these a.out NetBSD and OpenBSD obsolete configurations has
757 been removed. ELF variants of these configurations are kept supported.
759 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
760 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
761 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
762 i[34567]86-*-openbsd3.[0-3]
763 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
764 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
765 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
769 Like "catch throw", but catches a re-thrown exception.
771 Renamed from old "maint check-symtabs".
773 Perform consistency checks on symtabs.
775 Expand symtabs matching an optional regexp.
778 Display the details of GDB configure-time options.
780 maint set|show per-command
781 maint set|show per-command space
782 maint set|show per-command time
783 maint set|show per-command symtab
784 Enable display of per-command gdb resource usage.
786 remove-symbol-file FILENAME
787 remove-symbol-file -a ADDRESS
788 Remove a symbol file added via add-symbol-file. The file to remove
789 can be identified by its filename or by an address that lies within
790 the boundaries of this symbol file in memory.
793 info exceptions REGEXP
794 Display the list of Ada exceptions defined in the program being
795 debugged. If provided, only the exceptions whose names match REGEXP
800 set debug symfile off|on
802 Control display of debugging info regarding reading symbol files and
803 symbol tables within those files
805 set print raw frame-arguments
806 show print raw frame-arguments
807 Set/show whether to print frame arguments in raw mode,
808 disregarding any defined pretty-printers.
810 set remote trace-status-packet
811 show remote trace-status-packet
812 Set/show the use of remote protocol qTStatus packet.
816 Control display of debugging messages related to Nios II targets.
820 Control whether target-assisted range stepping is enabled.
822 set startup-with-shell
823 show startup-with-shell
824 Specifies whether Unix child processes are started via a shell or
829 Use the target memory cache for accesses to the code segment. This
830 improves performance of remote debugging (particularly disassembly).
832 * You can now use a literal value 'unlimited' for options that
833 interpret 0 or -1 as meaning "unlimited". E.g., "set
834 trace-buffer-size unlimited" is now an alias for "set
835 trace-buffer-size -1" and "set height unlimited" is now an alias for
838 * The "set debug symtab-create" debugging option of GDB has been changed to
839 accept a verbosity level. 0 means "off", 1 provides basic debugging
840 output, and values of 2 or greater provides more verbose output.
842 * New command-line options
844 Display the details of GDB configure-time options.
846 * The command 'tsave' can now support new option '-ctf' to save trace
847 buffer in Common Trace Format.
849 * Newly installed $prefix/bin/gcore acts as a shell interface for the
852 * GDB now implements the the C++ 'typeid' operator.
854 * The new convenience variable $_exception holds the exception being
855 thrown or caught at an exception-related catchpoint.
857 * The exception-related catchpoints, like "catch throw", now accept a
858 regular expression which can be used to filter exceptions by type.
860 * The new convenience variable $_exitsignal is automatically set to
861 the terminating signal number when the program being debugged dies
862 due to an uncaught signal.
866 ** All MI commands now accept an optional "--language" option.
867 Support for this feature can be verified by using the "-list-features"
868 command, which should contain "language-option".
870 ** The new command -info-gdb-mi-command allows the user to determine
871 whether a GDB/MI command is supported or not.
873 ** The "^error" result record returned when trying to execute an undefined
874 GDB/MI command now provides a variable named "code" whose content is the
875 "undefined-command" error code. Support for this feature can be verified
876 by using the "-list-features" command, which should contain
877 "undefined-command-error-code".
879 ** The -trace-save MI command can optionally save trace buffer in Common
882 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
884 ** The command -data-list-register-values now accepts an optional
885 "--skip-unavailable" option. When used, only the available registers
888 ** The new command -trace-frame-collected dumps collected variables,
889 computed expressions, tvars, memory and registers in a traceframe.
891 ** The commands -stack-list-locals, -stack-list-arguments and
892 -stack-list-variables now accept an option "--skip-unavailable".
893 When used, only the available locals or arguments are displayed.
895 ** The -exec-run command now accepts an optional "--start" option.
896 When used, the command follows the same semantics as the "start"
897 command, stopping the program's execution at the start of its
898 main subprogram. Support for this feature can be verified using
899 the "-list-features" command, which should contain
900 "exec-run-start-option".
902 ** The new commands -catch-assert and -catch-exceptions insert
903 catchpoints stopping the program when Ada exceptions are raised.
905 ** The new command -info-ada-exceptions provides the equivalent of
906 the new "info exceptions" command.
908 * New system-wide configuration scripts
909 A GDB installation now provides scripts suitable for use as system-wide
910 configuration scripts for the following systems:
914 * GDB now supports target-assigned range stepping with remote targets.
915 This improves the performance of stepping source lines by reducing
916 the number of control packets from/to GDB. See "New remote packets"
919 * GDB now understands the element 'tvar' in the XML traceframe info.
920 It has the id of the collected trace state variables.
922 * On S/390 targets that provide the transactional-execution feature,
923 the program interruption transaction diagnostic block (TDB) is now
924 represented as a number of additional "registers" in GDB.
930 The vCont packet supports a new 'r' action, that tells the remote
931 stub to step through an address range itself, without GDB
932 involvemement at each single-step.
934 qXfer:libraries-svr4:read's annex
935 The previously unused annex of the qXfer:libraries-svr4:read packet
936 is now used to support passing an argument list. The remote stub
937 reports support for this argument list to GDB's qSupported query.
938 The defined arguments are "start" and "prev", used to reduce work
939 necessary for library list updating, resulting in significant
942 * New features in the GDB remote stub, GDBserver
944 ** GDBserver now supports target-assisted range stepping. Currently
945 enabled on x86/x86_64 GNU/Linux targets.
947 ** GDBserver now adds element 'tvar' in the XML in the reply to
948 'qXfer:traceframe-info:read'. It has the id of the collected
949 trace state variables.
951 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
954 * New 'z' formatter for printing and examining memory, this displays the
955 value as hexadecimal zero padded on the left to the size of the type.
957 * GDB can now use Windows x64 unwinding data.
959 * The "set remotebaud" command has been replaced by "set serial baud".
960 Similarly, "show remotebaud" has been replaced by "show serial baud".
961 The "set remotebaud" and "show remotebaud" commands are still available
962 to provide backward compatibility with older versions of GDB.
964 *** Changes in GDB 7.6
966 * Target record has been renamed to record-full.
967 Record/replay is now enabled with the "record full" command.
968 This also affects settings that are associated with full record/replay
969 that have been moved from "set/show record" to "set/show record full":
971 set|show record full insn-number-max
972 set|show record full stop-at-limit
973 set|show record full memory-query
975 * A new record target "record-btrace" has been added. The new target
976 uses hardware support to record the control-flow of a process. It
977 does not support replaying the execution, but it implements the
978 below new commands for investigating the recorded execution log.
979 This new recording method can be enabled using:
983 The "record-btrace" target is only available on Intel Atom processors
984 and requires a Linux kernel 2.6.32 or later.
986 * Two new commands have been added for record/replay to give information
987 about the recorded execution without having to replay the execution.
988 The commands are only supported by "record btrace".
990 record instruction-history prints the execution history at
991 instruction granularity
993 record function-call-history prints the execution history at
996 * New native configurations
998 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
999 FreeBSD/powerpc powerpc*-*-freebsd
1000 x86_64/Cygwin x86_64-*-cygwin*
1001 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1005 ARM AArch64 aarch64*-*-elf
1006 ARM AArch64 GNU/Linux aarch64*-*-linux
1007 Lynx 178 PowerPC powerpc-*-lynx*178
1008 x86_64/Cygwin x86_64-*-cygwin*
1009 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1011 * If the configured location of system.gdbinit file (as given by the
1012 --with-system-gdbinit option at configure time) is in the
1013 data-directory (as specified by --with-gdb-datadir at configure
1014 time) or in one of its subdirectories, then GDB will look for the
1015 system-wide init file in the directory specified by the
1016 --data-directory command-line option.
1018 * New command line options:
1020 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1021 other initialization files, unlike -nx which disables all of them.
1023 * Removed command line options
1025 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1028 * The 'ptype' and 'whatis' commands now accept an argument to control
1031 * 'info proc' now works on some core files.
1035 ** Vectors can be created with gdb.Type.vector.
1037 ** Python's atexit.register now works in GDB.
1039 ** Types can be pretty-printed via a Python API.
1041 ** Python 3 is now supported (in addition to Python 2.4 or later)
1043 ** New class gdb.Architecture exposes GDB's internal representation
1044 of architecture in the Python API.
1046 ** New method Frame.architecture returns the gdb.Architecture object
1047 corresponding to the frame's architecture.
1049 * New Python-based convenience functions:
1051 ** $_memeq(buf1, buf2, length)
1052 ** $_streq(str1, str2)
1054 ** $_regex(str, regex)
1056 * The 'cd' command now defaults to using '~' (the home directory) if not
1059 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1060 default for GCC since November 2000.
1062 * The command 'forward-search' can now be abbreviated as 'fo'.
1064 * The command 'info tracepoints' can now display 'installed on target'
1065 or 'not installed on target' for each non-pending location of tracepoint.
1067 * New configure options
1069 --enable-libmcheck/--disable-libmcheck
1070 By default, development versions are built with -lmcheck on hosts
1071 that support it, in order to help track memory corruption issues.
1072 Release versions, on the other hand, are built without -lmcheck
1073 by default. The --enable-libmcheck/--disable-libmcheck configure
1074 options allow the user to override that default.
1075 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1076 This configure option allows the user to build GDB with
1077 libbabeltrace using which GDB can read Common Trace Format data.
1079 * New commands (for set/show, see "New options" below)
1082 Catch signals. This is similar to "handle", but allows commands and
1083 conditions to be attached.
1086 List the BFDs known to GDB.
1088 python-interactive [command]
1090 Start a Python interactive prompt, or evaluate the optional command
1091 and print the result of expressions.
1094 "py" is a new alias for "python".
1096 enable type-printer [name]...
1097 disable type-printer [name]...
1098 Enable or disable type printers.
1102 ** For the Renesas Super-H architecture, the "regs" command has been removed
1103 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1108 set print type methods (on|off)
1109 show print type methods
1110 Control whether method declarations are displayed by "ptype".
1111 The default is to show them.
1113 set print type typedefs (on|off)
1114 show print type typedefs
1115 Control whether typedef definitions are displayed by "ptype".
1116 The default is to show them.
1118 set filename-display basename|relative|absolute
1119 show filename-display
1120 Control the way in which filenames is displayed.
1121 The default is "relative", which preserves previous behavior.
1123 set trace-buffer-size
1124 show trace-buffer-size
1125 Request target to change the size of trace buffer.
1127 set remote trace-buffer-size-packet auto|on|off
1128 show remote trace-buffer-size-packet
1129 Control the use of the remote protocol `QTBuffer:size' packet.
1133 Control display of debugging messages related to ARM AArch64.
1136 set debug coff-pe-read
1137 show debug coff-pe-read
1138 Control display of debugging messages related to reading of COFF/PE
1143 Control display of debugging messages related to Mach-O symbols
1146 set debug notification
1147 show debug notification
1148 Control display of debugging info for async remote notification.
1152 ** Command parameter changes are now notified using new async record
1153 "=cmd-param-changed".
1154 ** Trace frame changes caused by command "tfind" are now notified using
1155 new async record "=traceframe-changed".
1156 ** The creation, deletion and modification of trace state variables
1157 are now notified using new async records "=tsv-created",
1158 "=tsv-deleted" and "=tsv-modified".
1159 ** The start and stop of process record are now notified using new
1160 async record "=record-started" and "=record-stopped".
1161 ** Memory changes are now notified using new async record
1163 ** The data-disassemble command response will include a "fullname" field
1164 containing the absolute file name when source has been requested.
1165 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1166 command, to allow pattern filling of memory areas.
1167 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1168 library load/unload events.
1169 ** The response to breakpoint commands and breakpoint async records
1170 includes an "installed" field containing a boolean state about each
1171 non-pending tracepoint location is whether installed on target or not.
1172 ** Output of the "-trace-status" command includes a "trace-file" field
1173 containing the name of the trace file being examined. This field is
1174 optional, and only present when examining a trace file.
1175 ** The "fullname" field is now always present along with the "file" field,
1176 even if the file cannot be found by GDB.
1178 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1179 You must have the LZMA library available when configuring GDB for this
1180 feature to be enabled. For more information, see:
1181 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1183 * New remote packets
1186 Set the size of trace buffer. The remote stub reports support for this
1187 packet to gdb's qSupported query.
1190 Enable Branch Trace Store (BTS)-based branch tracing for the current
1191 thread. The remote stub reports support for this packet to gdb's
1195 Disable branch tracing for the current thread. The remote stub reports
1196 support for this packet to gdb's qSupported query.
1199 Read the traced branches for the current thread. The remote stub
1200 reports support for this packet to gdb's qSupported query.
1202 *** Changes in GDB 7.5
1204 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1205 for more x32 ABI info.
1207 * GDB now supports access to MIPS DSP registers on Linux targets.
1209 * GDB now supports debugging microMIPS binaries.
1211 * The "info os" command on GNU/Linux can now display information on
1212 several new classes of objects managed by the operating system:
1213 "info os procgroups" lists process groups
1214 "info os files" lists file descriptors
1215 "info os sockets" lists internet-domain sockets
1216 "info os shm" lists shared-memory regions
1217 "info os semaphores" lists semaphores
1218 "info os msg" lists message queues
1219 "info os modules" lists loaded kernel modules
1221 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1222 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1223 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1224 options and inspect the probe arguments using the new $_probe_arg family
1225 of convenience variables. You can obtain more information about SystemTap
1226 in <http://sourceware.org/systemtap/>.
1228 * GDB now supports reversible debugging on ARM, it allows you to
1229 debug basic ARM and THUMB instructions, and provides
1230 record/replay support.
1232 * The option "symbol-reloading" has been deleted as it is no longer used.
1236 ** GDB commands implemented in Python can now be put in command class
1239 ** The "maint set python print-stack on|off" is now deleted.
1241 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1242 apply "flag enum"-style pretty-printing to any enum.
1244 ** gdb.lookup_symbol can now work when there is no current frame.
1246 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1247 the source at which the symbol was defined.
1249 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1250 method 'value'. The former indicates whether the symbol needs a
1251 frame in order to compute its value, and the latter computes the
1254 ** A new method 'referenced_value' on gdb.Value objects which can
1255 dereference pointer as well as C++ reference values.
1257 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1258 which return the global and static blocks (as gdb.Block objects),
1259 of the underlying symbol table, respectively.
1261 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1262 object associated with a PC value.
1264 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1265 of the address range occupied by code for the current source line.
1267 * Go language support.
1268 GDB now supports debugging programs written in the Go programming
1271 * GDBserver now supports stdio connections.
1272 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1274 * The binary "gdbtui" can no longer be built or installed.
1275 Use "gdb -tui" instead.
1277 * GDB will now print "flag" enums specially. A flag enum is one where
1278 all the enumerator values have no bits in common when pairwise
1279 "and"ed. When printing a value whose type is a flag enum, GDB will
1280 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1281 (gdb) print (enum E) 3
1284 * The filename part of a linespec will now match trailing components
1285 of a source file name. For example, "break gcc/expr.c:1000" will
1286 now set a breakpoint in build/gcc/expr.c, but not
1287 build/libcpp/expr.c.
1289 * The "info proc" and "generate-core-file" commands will now also
1290 work on remote targets connected to GDBserver on Linux.
1292 * The command "info catch" has been removed. It has been disabled
1293 since December 2007.
1295 * The "catch exception" and "catch assert" commands now accept
1296 a condition at the end of the command, much like the "break"
1297 command does. For instance:
1299 (gdb) catch exception Constraint_Error if Barrier = True
1301 Previously, it was possible to add a condition to such catchpoints,
1302 but it had to be done as a second step, after the catchpoint had been
1303 created, using the "condition" command.
1305 * The "info static-tracepoint-marker" command will now also work on
1306 native Linux targets with in-process agent.
1308 * GDB can now set breakpoints on inlined functions.
1310 * The .gdb_index section has been updated to include symbols for
1311 inlined functions. GDB will ignore older .gdb_index sections by
1312 default, which could cause symbol files to be loaded more slowly
1313 until their .gdb_index sections can be recreated. The new command
1314 "set use-deprecated-index-sections on" will cause GDB to use any older
1315 .gdb_index sections it finds. This will restore performance, but the
1316 ability to set breakpoints on inlined functions will be lost in symbol
1317 files with older .gdb_index sections.
1319 The .gdb_index section has also been updated to record more information
1320 about each symbol. This speeds up the "info variables", "info functions"
1321 and "info types" commands when used with programs having the .gdb_index
1322 section, as well as speeding up debugging with shared libraries using
1323 the .gdb_index section.
1325 * Ada support for GDB/MI Variable Objects has been added.
1327 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1332 ** New command -info-os is the MI equivalent of "info os".
1334 ** Output logs ("set logging" and related) now include MI output.
1338 ** "set use-deprecated-index-sections on|off"
1339 "show use-deprecated-index-sections on|off"
1340 Controls the use of deprecated .gdb_index sections.
1342 ** "catch load" and "catch unload" can be used to stop when a shared
1343 library is loaded or unloaded, respectively.
1345 ** "enable count" can be used to auto-disable a breakpoint after
1348 ** "info vtbl" can be used to show the virtual method tables for
1349 C++ and Java objects.
1351 ** "explore" and its sub commands "explore value" and "explore type"
1352 can be used to recursively explore values and types of
1353 expressions. These commands are available only if GDB is
1354 configured with '--with-python'.
1356 ** "info auto-load" shows status of all kinds of auto-loaded files,
1357 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1358 sequences of commands files, "info auto-load python-scripts"
1359 shows status of auto-loading Python script files,
1360 "info auto-load local-gdbinit" shows status of loading init file
1361 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1362 status of inferior specific thread debugging shared library loading.
1364 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1365 and "show auto-load-scripts" commands have been deprecated, use their
1366 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1367 and "show auto-load python-scripts" counterparts instead.
1369 ** "dprintf location,format,args..." creates a dynamic printf, which
1370 is basically a breakpoint that does a printf and immediately
1371 resumes your program's execution, so it is like a printf that you
1372 can insert dynamically at runtime instead of at compiletime.
1374 ** "set print symbol"
1376 Controls whether GDB attempts to display the symbol, if any,
1377 corresponding to addresses it prints. This defaults to "on", but
1378 you can set it to "off" to restore GDB's previous behavior.
1380 * Deprecated commands
1382 ** For the Renesas Super-H architecture, the "regs" command has been
1383 deprecated, and "info all-registers" should be used instead.
1387 Renesas RL78 rl78-*-elf
1388 HP OpenVMS ia64 ia64-hp-openvms*
1390 * GDBserver supports evaluation of breakpoint conditions. When
1391 support is advertised by GDBserver, GDB may be told to send the
1392 breakpoint conditions in bytecode form to GDBserver. GDBserver
1393 will only report the breakpoint trigger to GDB when its condition
1398 set mips compression
1399 show mips compression
1400 Select the compressed ISA encoding used in functions that have no symbol
1401 information available. The encoding can be set to either of:
1404 and is updated automatically from ELF file flags if available.
1406 set breakpoint condition-evaluation
1407 show breakpoint condition-evaluation
1408 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1409 GDBserver ("target"). Default option "auto" chooses the most efficient
1411 This option can improve debugger efficiency depending on the speed of the
1415 Disable auto-loading globally.
1418 Show auto-loading setting of all kinds of auto-loaded files.
1420 set auto-load gdb-scripts on|off
1421 show auto-load gdb-scripts
1422 Control auto-loading of GDB canned sequences of commands files.
1424 set auto-load python-scripts on|off
1425 show auto-load python-scripts
1426 Control auto-loading of Python script files.
1428 set auto-load local-gdbinit on|off
1429 show auto-load local-gdbinit
1430 Control loading of init file (.gdbinit) from current directory.
1432 set auto-load libthread-db on|off
1433 show auto-load libthread-db
1434 Control auto-loading of inferior specific thread debugging shared library.
1436 set auto-load scripts-directory <dir1>[:<dir2>...]
1437 show auto-load scripts-directory
1438 Set a list of directories from which to load auto-loaded scripts.
1439 Automatically loaded Python scripts and GDB scripts are located in one
1440 of the directories listed by this option.
1441 The delimiter (':' above) may differ according to the host platform.
1443 set auto-load safe-path <dir1>[:<dir2>...]
1444 show auto-load safe-path
1445 Set a list of directories from which it is safe to auto-load files.
1446 The delimiter (':' above) may differ according to the host platform.
1448 set debug auto-load on|off
1449 show debug auto-load
1450 Control display of debugging info for auto-loading the files above.
1452 set dprintf-style gdb|call|agent
1454 Control the way in which a dynamic printf is performed; "gdb"
1455 requests a GDB printf command, while "call" causes dprintf to call a
1456 function in the inferior. "agent" requests that the target agent
1457 (such as GDBserver) do the printing.
1459 set dprintf-function <expr>
1460 show dprintf-function
1461 set dprintf-channel <expr>
1462 show dprintf-channel
1463 Set the function and optional first argument to the call when using
1464 the "call" style of dynamic printf.
1466 set disconnected-dprintf on|off
1467 show disconnected-dprintf
1468 Control whether agent-style dynamic printfs continue to be in effect
1469 after GDB disconnects.
1471 * New configure options
1473 --with-auto-load-dir
1474 Configure default value for the 'set auto-load scripts-directory'
1475 setting above. It defaults to '$debugdir:$datadir/auto-load',
1476 $debugdir representing global debugging info directories (available
1477 via 'show debug-file-directory') and $datadir representing GDB's data
1478 directory (available via 'show data-directory').
1480 --with-auto-load-safe-path
1481 Configure default value for the 'set auto-load safe-path' setting
1482 above. It defaults to the --with-auto-load-dir setting.
1484 --without-auto-load-safe-path
1485 Set 'set auto-load safe-path' to '/', effectively disabling this
1488 * New remote packets
1490 z0/z1 conditional breakpoints extension
1492 The z0/z1 breakpoint insertion packets have been extended to carry
1493 a list of conditional expressions over to the remote stub depending on the
1494 condition evaluation mode. The use of this extension can be controlled
1495 via the "set remote conditional-breakpoints-packet" command.
1499 Specify the signals which the remote stub may pass to the debugged
1500 program without GDB involvement.
1502 * New command line options
1504 --init-command=FILE, -ix Like --command, -x but execute it
1505 before loading inferior.
1506 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1507 execute it before loading inferior.
1509 *** Changes in GDB 7.4
1511 * GDB now handles ambiguous linespecs more consistently; the existing
1512 FILE:LINE support has been expanded to other types of linespecs. A
1513 breakpoint will now be set on all matching locations in all
1514 inferiors, and locations will be added or removed according to
1517 * GDB now allows you to skip uninteresting functions and files when
1518 stepping with the "skip function" and "skip file" commands.
1520 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1521 and "show remote hardware-watchpoint-length-limit". These allows to
1522 set or show the maximum length limit (in bytes) of a remote
1523 target hardware watchpoint.
1525 This allows e.g. to use "unlimited" hardware watchpoints with the
1526 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1527 watchpoints are slower than real hardware watchpoints but are
1528 significantly faster than gdb software watchpoints.
1532 ** The register_pretty_printer function in module gdb.printing now takes
1533 an optional `replace' argument. If True, the new printer replaces any
1536 ** The "maint set python print-stack on|off" command has been
1537 deprecated and will be deleted in GDB 7.5.
1538 A new command: "set python print-stack none|full|message" has
1539 replaced it. Additionally, the default for "print-stack" is
1540 now "message", which just prints the error message without
1543 ** A prompt substitution hook (prompt_hook) is now available to the
1546 ** A new Python module, gdb.prompt has been added to the GDB Python
1547 modules library. This module provides functionality for
1548 escape sequences in prompts (used by set/show
1549 extended-prompt). These escape sequences are replaced by their
1550 corresponding value.
1552 ** Python commands and convenience-functions located in
1553 'data-directory'/python/gdb/command and
1554 'data-directory'/python/gdb/function are now automatically loaded
1557 ** Blocks now provide four new attributes. global_block and
1558 static_block will return the global and static blocks
1559 respectively. is_static and is_global are boolean attributes
1560 that indicate if the block is one of those two types.
1562 ** Symbols now provide the "type" attribute, the type of the symbol.
1564 ** The "gdb.breakpoint" function has been deprecated in favor of
1567 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1568 of a function. This class is based on the "finish" command
1569 available in the CLI.
1571 ** Type objects for struct and union types now allow access to
1572 the fields using standard Python dictionary (mapping) methods.
1573 For example, "some_type['myfield']" now works, as does
1574 "some_type.items()".
1576 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1579 ** A new function, "deep_items" has been added to the gdb.types
1580 module in the GDB Python modules library. This function returns
1581 an iterator over the fields of a struct or union type. Unlike
1582 the standard Python "iteritems" method, it will recursively traverse
1583 any anonymous fields.
1587 ** "*stopped" events can report several new "reason"s, such as
1590 ** Breakpoint changes are now notified using new async records, like
1591 "=breakpoint-modified".
1593 ** New command -ada-task-info.
1595 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1596 $sdir specifies the default system locations of shared libraries.
1597 $pdir specifies the directory where the libpthread used by the application
1600 GDB no longer looks in $sdir and $pdir after it has searched the directories
1601 mentioned in libthread-db-search-path. If you want to search those
1602 directories, they must be specified in libthread-db-search-path.
1603 The default value of libthread-db-search-path on GNU/Linux and Solaris
1604 systems is now "$sdir:$pdir".
1606 $pdir is not supported by gdbserver, it is currently ignored.
1607 $sdir is supported by gdbserver.
1609 * New configure option --with-iconv-bin.
1610 When using the internationalization support like the one in the GNU C
1611 library, GDB will invoke the "iconv" program to get a list of supported
1612 character sets. If this program lives in a non-standard location, one can
1613 use this option to specify where to find it.
1615 * When natively debugging programs on PowerPC BookE processors running
1616 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1617 watchpoints, which specify a mask in addition to an address to watch.
1618 The mask specifies that some bits of an address (the bits which are
1619 reset in the mask) should be ignored when matching the address accessed
1620 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1621 section in the user manual for more details.
1623 * The new option --once causes GDBserver to stop listening for connections once
1624 the first connection is made. The listening port used by GDBserver will
1625 become available after that.
1627 * New commands "info macros" and "alias" have been added.
1629 * New function parameters suffix @entry specifies value of function parameter
1630 at the time the function got called. Entry values are available only since
1636 "!" is now an alias of the "shell" command.
1637 Note that no space is needed between "!" and SHELL COMMAND.
1641 watch EXPRESSION mask MASK_VALUE
1642 The watch command now supports the mask argument which allows creation
1643 of masked watchpoints, if the current architecture supports this feature.
1645 info auto-load-scripts [REGEXP]
1646 This command was formerly named "maintenance print section-scripts".
1647 It is now generally useful and is no longer a maintenance-only command.
1649 info macro [-all] [--] MACRO
1650 The info macro command has new options `-all' and `--'. The first for
1651 printing all definitions of a macro. The second for explicitly specifying
1652 the end of arguments and the beginning of the macro name in case the macro
1653 name starts with a hyphen.
1655 collect[/s] EXPRESSIONS
1656 The tracepoint collect command now takes an optional modifier "/s"
1657 that directs it to dereference pointer-to-character types and
1658 collect the bytes of memory up to a zero byte. The behavior is
1659 similar to what you see when you use the regular print command on a
1660 string. An optional integer following the "/s" sets a bound on the
1661 number of bytes that will be collected.
1664 The trace start command now interprets any supplied arguments as a
1665 note to be recorded with the trace run, with an effect similar to
1666 setting the variable trace-notes.
1669 The trace stop command now interprets any arguments as a note to be
1670 mentioned along with the tstatus report that the trace was stopped
1671 with a command. The effect is similar to setting the variable
1674 * Tracepoints can now be enabled and disabled at any time after a trace
1675 experiment has been started using the standard "enable" and "disable"
1676 commands. It is now possible to start a trace experiment with no enabled
1677 tracepoints; GDB will display a warning, but will allow the experiment to
1678 begin, assuming that tracepoints will be enabled as needed while the trace
1681 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1682 locations with 4-byte instructions, when they were previously
1683 limited to locations with instructions of 5 bytes or longer.
1687 set debug dwarf2-read
1688 show debug dwarf2-read
1689 Turns on or off display of debugging messages related to reading
1690 DWARF debug info. The default is off.
1692 set debug symtab-create
1693 show debug symtab-create
1694 Turns on or off display of debugging messages related to symbol table
1695 creation. The default is off.
1698 show extended-prompt
1699 Set the GDB prompt, and allow escape sequences to be inserted to
1700 display miscellaneous information (see 'help set extended-prompt'
1701 for the list of sequences). This prompt (and any information
1702 accessed through the escape sequences) is updated every time the
1703 prompt is displayed.
1705 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1706 show print entry-values
1707 Set printing of frame argument values at function entry. In some cases
1708 GDB can determine the value of function argument which was passed by the
1709 function caller, even if the value was modified inside the called function.
1711 set debug entry-values
1712 show debug entry-values
1713 Control display of debugging info for determining frame argument values at
1714 function entry and virtual tail call frames.
1716 set basenames-may-differ
1717 show basenames-may-differ
1718 Set whether a source file may have multiple base names.
1719 (A "base name" is the name of a file with the directory part removed.
1720 Example: The base name of "/home/user/hello.c" is "hello.c".)
1721 If set, GDB will canonicalize file names (e.g., expand symlinks)
1722 before comparing them. Canonicalization is an expensive operation,
1723 but it allows the same file be known by more than one base name.
1724 If not set (the default), all source files are assumed to have just
1725 one base name, and gdb will do file name comparisons more efficiently.
1731 Set a user name and notes for the current and any future trace runs.
1732 This is useful for long-running and/or disconnected traces, to
1733 inform others (or yourself) as to who is running the trace, supply
1734 contact information, or otherwise explain what is going on.
1736 set trace-stop-notes
1737 show trace-stop-notes
1738 Set a note attached to the trace run, that is displayed when the
1739 trace has been stopped by a tstop command. This is useful for
1740 instance as an explanation, if you are stopping a trace run that was
1741 started by someone else.
1743 * New remote packets
1747 Dynamically enable a tracepoint in a started trace experiment.
1751 Dynamically disable a tracepoint in a started trace experiment.
1755 Set the user and notes of the trace run.
1759 Query the current status of a tracepoint.
1763 Query the minimum length of instruction at which a fast tracepoint may
1766 * Dcache size (number of lines) and line-size are now runtime-configurable
1767 via "set dcache line" and "set dcache line-size" commands.
1771 Texas Instruments TMS320C6x tic6x-*-*
1775 Renesas RL78 rl78-*-elf
1777 *** Changes in GDB 7.3.1
1779 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1781 *** Changes in GDB 7.3
1783 * GDB has a new command: "thread find [REGEXP]".
1784 It finds the thread id whose name, target id, or thread extra info
1785 matches the given regular expression.
1787 * The "catch syscall" command now works on mips*-linux* targets.
1789 * The -data-disassemble MI command now supports modes 2 and 3 for
1790 dumping the instruction opcodes.
1792 * New command line options
1794 -data-directory DIR Specify DIR as the "data-directory".
1795 This is mostly for testing purposes.
1797 * The "maint set python auto-load on|off" command has been renamed to
1798 "set auto-load-scripts on|off".
1800 * GDB has a new command: "set directories".
1801 It is like the "dir" command except that it replaces the
1802 source path list instead of augmenting it.
1804 * GDB now understands thread names.
1806 On GNU/Linux, "info threads" will display the thread name as set by
1807 prctl or pthread_setname_np.
1809 There is also a new command, "thread name", which can be used to
1810 assign a name internally for GDB to display.
1813 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1814 has been integrated into GDB.
1818 ** The function gdb.Write now accepts an optional keyword 'stream'.
1819 This keyword, when provided, will direct the output to either
1820 stdout, stderr, or GDB's logging output.
1822 ** Parameters can now be be sub-classed in Python, and in particular
1823 you may implement the get_set_doc and get_show_doc functions.
1824 This improves how Parameter set/show documentation is processed
1825 and allows for more dynamic content.
1827 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1828 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1829 have an is_valid method.
1831 ** Breakpoints can now be sub-classed in Python, and in particular
1832 you may implement a 'stop' function that is executed each time
1833 the inferior reaches that breakpoint.
1835 ** New function gdb.lookup_global_symbol looks up a global symbol.
1837 ** GDB values in Python are now callable if the value represents a
1838 function. For example, if 'some_value' represents a function that
1839 takes two integer parameters and returns a value, you can call
1840 that function like so:
1842 result = some_value (10,20)
1844 ** Module gdb.types has been added.
1845 It contains a collection of utilities for working with gdb.Types objects:
1846 get_basic_type, has_field, make_enum_dict.
1848 ** Module gdb.printing has been added.
1849 It contains utilities for writing and registering pretty-printers.
1850 New classes: PrettyPrinter, SubPrettyPrinter,
1851 RegexpCollectionPrettyPrinter.
1852 New function: register_pretty_printer.
1854 ** New commands "info pretty-printers", "enable pretty-printer" and
1855 "disable pretty-printer" have been added.
1857 ** gdb.parameter("directories") is now available.
1859 ** New function gdb.newest_frame returns the newest frame in the
1862 ** The gdb.InferiorThread class has a new "name" attribute. This
1863 holds the thread's name.
1865 ** Python Support for Inferior events.
1866 Python scripts can add observers to be notified of events
1867 occurring in the process being debugged.
1868 The following events are currently supported:
1869 - gdb.events.cont Continue event.
1870 - gdb.events.exited Inferior exited event.
1871 - gdb.events.stop Signal received, and Breakpoint hit events.
1875 ** GDB now puts template parameters in scope when debugging in an
1876 instantiation. For example, if you have:
1878 template<int X> int func (void) { return X; }
1880 then if you step into func<5>, "print X" will show "5". This
1881 feature requires proper debuginfo support from the compiler; it
1882 was added to GCC 4.5.
1884 ** The motion commands "next", "finish", "until", and "advance" now
1885 work better when exceptions are thrown. In particular, GDB will
1886 no longer lose control of the inferior; instead, the GDB will
1887 stop the inferior at the point at which the exception is caught.
1888 This functionality requires a change in the exception handling
1889 code that was introduced in GCC 4.5.
1891 * GDB now follows GCC's rules on accessing volatile objects when
1892 reading or writing target state during expression evaluation.
1893 One notable difference to prior behavior is that "print x = 0"
1894 no longer generates a read of x; the value of the assignment is
1895 now always taken directly from the value being assigned.
1897 * GDB now has some support for using labels in the program's source in
1898 linespecs. For instance, you can use "advance label" to continue
1899 execution to a label.
1901 * GDB now has support for reading and writing a new .gdb_index
1902 section. This section holds a fast index of DWARF debugging
1903 information and can be used to greatly speed up GDB startup and
1904 operation. See the documentation for `save gdb-index' for details.
1906 * The "watch" command now accepts an optional "-location" argument.
1907 When used, this causes GDB to watch the memory referred to by the
1908 expression. Such a watchpoint is never deleted due to it going out
1911 * GDB now supports thread debugging of core dumps on GNU/Linux.
1913 GDB now activates thread debugging using the libthread_db library
1914 when debugging GNU/Linux core dumps, similarly to when debugging
1915 live processes. As a result, when debugging a core dump file, GDB
1916 is now able to display pthread_t ids of threads. For example, "info
1917 threads" shows the same output as when debugging the process when it
1918 was live. In earlier releases, you'd see something like this:
1921 * 1 LWP 6780 main () at main.c:10
1923 While now you see this:
1926 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1928 It is also now possible to inspect TLS variables when debugging core
1931 When debugging a core dump generated on a machine other than the one
1932 used to run GDB, you may need to point GDB at the correct
1933 libthread_db library with the "set libthread-db-search-path"
1934 command. See the user manual for more details on this command.
1936 * When natively debugging programs on PowerPC BookE processors running
1937 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1938 which stop execution of the inferior whenever it executes an instruction
1939 at any address within the specified range. See the "PowerPC Embedded"
1940 section in the user manual for more details.
1942 * New features in the GDB remote stub, GDBserver
1944 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1945 and i686 LynxOS (version 5.x).
1947 ** GDBserver is now supported on Blackfin Linux.
1949 * New native configurations
1951 ia64 HP-UX ia64-*-hpux*
1955 Analog Devices, Inc. Blackfin Processor bfin-*
1957 * Ada task switching is now supported on sparc-elf targets when
1958 debugging a program using the Ravenscar Profile. For more information,
1959 see the "Tasking Support when using the Ravenscar Profile" section
1960 in the GDB user manual.
1962 * Guile support was removed.
1964 * New features in the GNU simulator
1966 ** The --map-info flag lists all known core mappings.
1968 ** CFI flashes may be simulated via the "cfi" device.
1970 *** Changes in GDB 7.2
1972 * Shared library support for remote targets by default
1974 When GDB is configured for a generic, non-OS specific target, like
1975 for example, --target=arm-eabi or one of the many *-*-elf targets,
1976 GDB now queries remote stubs for loaded shared libraries using the
1977 `qXfer:libraries:read' packet. Previously, shared library support
1978 was always disabled for such configurations.
1982 ** Argument Dependent Lookup (ADL)
1984 In C++ ADL lookup directs function search to the namespaces of its
1985 arguments even if the namespace has not been imported.
1995 Here the compiler will search for `foo' in the namespace of 'b'
1996 and find A::foo. GDB now supports this. This construct is commonly
1997 used in the Standard Template Library for operators.
1999 ** Improved User Defined Operator Support
2001 In addition to member operators, GDB now supports lookup of operators
2002 defined in a namespace and imported with a `using' directive, operators
2003 defined in the global scope, operators imported implicitly from an
2004 anonymous namespace, and the ADL operators mentioned in the previous
2006 GDB now also supports proper overload resolution for all the previously
2007 mentioned flavors of operators.
2009 ** static const class members
2011 Printing of static const class members that are initialized in the
2012 class definition has been fixed.
2014 * Windows Thread Information Block access.
2016 On Windows targets, GDB now supports displaying the Windows Thread
2017 Information Block (TIB) structure. This structure is visible either
2018 by using the new command `info w32 thread-information-block' or, by
2019 dereferencing the new convenience variable named `$_tlb', a
2020 thread-specific pointer to the TIB. This feature is also supported
2021 when remote debugging using GDBserver.
2023 * Static tracepoints
2025 Static tracepoints are calls in the user program into a tracing
2026 library. One such library is a port of the LTTng kernel tracer to
2027 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2028 When debugging with GDBserver, GDB now supports combining the GDB
2029 tracepoint machinery with such libraries. For example: the user can
2030 use GDB to probe a static tracepoint marker (a call from the user
2031 program into the tracing library) with the new "strace" command (see
2032 "New commands" below). This creates a "static tracepoint" in the
2033 breakpoint list, that can be manipulated with the same feature set
2034 as fast and regular tracepoints. E.g., collect registers, local and
2035 global variables, collect trace state variables, and define
2036 tracepoint conditions. In addition, the user can collect extra
2037 static tracepoint marker specific data, by collecting the new
2038 $_sdata internal variable. When analyzing the trace buffer, you can
2039 inspect $_sdata like any other variable available to GDB. For more
2040 information, see the "Tracepoints" chapter in GDB user manual. New
2041 remote packets have been defined to support static tracepoints, see
2042 the "New remote packets" section below.
2044 * Better reconstruction of tracepoints after disconnected tracing
2046 GDB will attempt to download the original source form of tracepoint
2047 definitions when starting a trace run, and then will upload these
2048 upon reconnection to the target, resulting in a more accurate
2049 reconstruction of the tracepoints that are in use on the target.
2053 You can now exercise direct control over the ways that GDB can
2054 affect your program. For instance, you can disallow the setting of
2055 breakpoints, so that the program can run continuously (assuming
2056 non-stop mode). In addition, the "observer" variable is available
2057 to switch all of the different controls; in observer mode, GDB
2058 cannot affect the target's behavior at all, which is useful for
2059 tasks like diagnosing live systems in the field.
2061 * The new convenience variable $_thread holds the number of the
2064 * New remote packets
2068 Return the address of the Windows Thread Information Block of a given thread.
2072 In response to several of the tracepoint packets, the target may now
2073 also respond with a number of intermediate `qRelocInsn' request
2074 packets before the final result packet, to have GDB handle
2075 relocating an instruction to execute at a different address. This
2076 is particularly useful for stubs that support fast tracepoints. GDB
2077 reports support for this feature in the qSupported packet.
2081 List static tracepoint markers in the target program.
2085 List static tracepoint markers at a given address in the target
2088 qXfer:statictrace:read
2090 Read the static trace data collected (by a `collect $_sdata'
2091 tracepoint action). The remote stub reports support for this packet
2092 to gdb's qSupported query.
2096 Send the current settings of GDB's permission flags.
2100 Send part of the source (textual) form of a tracepoint definition,
2101 which includes location, conditional, and action list.
2103 * The source command now accepts a -s option to force searching for the
2104 script in the source search path even if the script name specifies
2107 * New features in the GDB remote stub, GDBserver
2109 - GDBserver now support tracepoints (including fast tracepoints, and
2110 static tracepoints). The feature is currently supported by the
2111 i386-linux and amd64-linux builds. See the "Tracepoints support
2112 in gdbserver" section in the manual for more information.
2114 GDBserver JIT compiles the tracepoint's conditional agent
2115 expression bytecode into native code whenever possible for low
2116 overhead dynamic tracepoints conditionals. For such tracepoints,
2117 an expression that examines program state is evaluated when the
2118 tracepoint is reached, in order to determine whether to capture
2119 trace data. If the condition is simple and false, processing the
2120 tracepoint finishes very quickly and no data is gathered.
2122 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2123 for static tracepoints support.
2125 - GDBserver now supports x86_64 Windows 64-bit debugging.
2127 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2128 it understands register description.
2130 * The --batch flag now disables pagination and queries.
2132 * X86 general purpose registers
2134 GDB now supports reading/writing byte, word and double-word x86
2135 general purpose registers directly. This means you can use, say,
2136 $ah or $ax to refer, respectively, to the byte register AH and
2137 16-bit word register AX that are actually portions of the 32-bit
2138 register EAX or 64-bit register RAX.
2140 * The `commands' command now accepts a range of breakpoints to modify.
2141 A plain `commands' following a command that creates multiple
2142 breakpoints affects all the breakpoints set by that command. This
2143 applies to breakpoints set by `rbreak', and also applies when a
2144 single `break' command creates multiple breakpoints (e.g.,
2145 breakpoints on overloaded c++ functions).
2147 * The `rbreak' command now accepts a filename specification as part of
2148 its argument, limiting the functions selected by the regex to those
2149 in the specified file.
2151 * Support for remote debugging Windows and SymbianOS shared libraries
2152 from Unix hosts has been improved. Non Windows GDB builds now can
2153 understand target reported file names that follow MS-DOS based file
2154 system semantics, such as file names that include drive letters and
2155 use the backslash character as directory separator. This makes it
2156 possible to transparently use the "set sysroot" and "set
2157 solib-search-path" on Unix hosts to point as host copies of the
2158 target's shared libraries. See the new command "set
2159 target-file-system-kind" described below, and the "Commands to
2160 specify files" section in the user manual for more information.
2164 eval template, expressions...
2165 Convert the values of one or more expressions under the control
2166 of the string template to a command line, and call it.
2168 set target-file-system-kind unix|dos-based|auto
2169 show target-file-system-kind
2170 Set or show the assumed file system kind for target reported file
2173 save breakpoints <filename>
2174 Save all current breakpoint definitions to a file suitable for use
2175 in a later debugging session. To read the saved breakpoint
2176 definitions, use the `source' command.
2178 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2181 info static-tracepoint-markers
2182 Display information about static tracepoint markers in the target.
2184 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2185 Define a static tracepoint by probing a marker at the given
2186 function, line, address, or marker ID.
2190 Enable and disable observer mode.
2192 set may-write-registers on|off
2193 set may-write-memory on|off
2194 set may-insert-breakpoints on|off
2195 set may-insert-tracepoints on|off
2196 set may-insert-fast-tracepoints on|off
2197 set may-interrupt on|off
2198 Set individual permissions for GDB effects on the target. Note that
2199 some of these settings can have undesirable or surprising
2200 consequences, particularly when changed in the middle of a session.
2201 For instance, disabling the writing of memory can prevent
2202 breakpoints from being inserted, cause single-stepping to fail, or
2203 even crash your program, if you disable after breakpoints have been
2204 inserted. However, GDB should not crash.
2206 set record memory-query on|off
2207 show record memory-query
2208 Control whether to stop the inferior if memory changes caused
2209 by an instruction cannot be recorded.
2214 The disassemble command now supports "start,+length" form of two arguments.
2218 ** GDB now provides a new directory location, called the python directory,
2219 where Python scripts written for GDB can be installed. The location
2220 of that directory is <data-directory>/python, where <data-directory>
2221 is the GDB data directory. For more details, see section `Scripting
2222 GDB using Python' in the manual.
2224 ** The GDB Python API now has access to breakpoints, symbols, symbol
2225 tables, program spaces, inferiors, threads and frame's code blocks.
2226 Additionally, GDB Parameters can now be created from the API, and
2227 manipulated via set/show in the CLI.
2229 ** New functions gdb.target_charset, gdb.target_wide_charset,
2230 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2232 ** New exception gdb.GdbError.
2234 ** Pretty-printers are now also looked up in the current program space.
2236 ** Pretty-printers can now be individually enabled and disabled.
2238 ** GDB now looks for names of Python scripts to auto-load in a
2239 special section named `.debug_gdb_scripts', in addition to looking
2240 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2242 * Tracepoint actions were unified with breakpoint commands. In particular,
2243 there are no longer differences in "info break" output for breakpoints and
2244 tracepoints and the "commands" command can be used for both tracepoints and
2245 regular breakpoints.
2249 ARM Symbian arm*-*-symbianelf*
2251 * D language support.
2252 GDB now supports debugging programs written in the D programming
2255 * GDB now supports the extended ptrace interface for PowerPC which is
2256 available since Linux kernel version 2.6.34. This automatically enables
2257 any hardware breakpoints and additional hardware watchpoints available in
2258 the processor. The old ptrace interface exposes just one hardware
2259 watchpoint and no hardware breakpoints.
2261 * GDB is now able to use the Data Value Compare (DVC) register available on
2262 embedded PowerPC processors to implement in hardware simple watchpoint
2263 conditions of the form:
2265 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2267 This works in native GDB running on Linux kernels with the extended ptrace
2268 interface mentioned above.
2270 *** Changes in GDB 7.1
2274 ** Namespace Support
2276 GDB now supports importing of namespaces in C++. This enables the
2277 user to inspect variables from imported namespaces. Support for
2278 namepace aliasing has also been added. So, if a namespace is
2279 aliased in the current scope (e.g. namepace C=A; ) the user can
2280 print variables using the alias (e.g. (gdb) print C::x).
2284 All known bugs relating to the printing of virtual base class were
2285 fixed. It is now possible to call overloaded static methods using a
2290 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2291 and reinterpret_cast<> are now handled by the C++ expression parser.
2295 Xilinx MicroBlaze microblaze-*-*
2300 Xilinx MicroBlaze microblaze
2303 * Multi-program debugging.
2305 GDB now has support for multi-program (a.k.a. multi-executable or
2306 multi-exec) debugging. This allows for debugging multiple inferiors
2307 simultaneously each running a different program under the same GDB
2308 session. See "Debugging Multiple Inferiors and Programs" in the
2309 manual for more information. This implied some user visible changes
2310 in the multi-inferior support. For example, "info inferiors" now
2311 lists inferiors that are not running yet or that have exited
2312 already. See also "New commands" and "New options" below.
2314 * New tracing features
2316 GDB's tracepoint facility now includes several new features:
2318 ** Trace state variables
2320 GDB tracepoints now include support for trace state variables, which
2321 are variables managed by the target agent during a tracing
2322 experiment. They are useful for tracepoints that trigger each
2323 other, so for instance one tracepoint can count hits in a variable,
2324 and then a second tracepoint has a condition that is true when the
2325 count reaches a particular value. Trace state variables share the
2326 $-syntax of GDB convenience variables, and can appear in both
2327 tracepoint actions and condition expressions. Use the "tvariable"
2328 command to create, and "info tvariables" to view; see "Trace State
2329 Variables" in the manual for more detail.
2333 GDB now includes an option for defining fast tracepoints, which
2334 targets may implement more efficiently, such as by installing a jump
2335 into the target agent rather than a trap instruction. The resulting
2336 speedup can be by two orders of magnitude or more, although the
2337 tradeoff is that some program locations on some target architectures
2338 might not allow fast tracepoint installation, for instance if the
2339 instruction to be replaced is shorter than the jump. To request a
2340 fast tracepoint, use the "ftrace" command, with syntax identical to
2341 the regular trace command.
2343 ** Disconnected tracing
2345 It is now possible to detach GDB from the target while it is running
2346 a trace experiment, then reconnect later to see how the experiment
2347 is going. In addition, a new variable disconnected-tracing lets you
2348 tell the target agent whether to continue running a trace if the
2349 connection is lost unexpectedly.
2353 GDB now has the ability to save the trace buffer into a file, and
2354 then use that file as a target, similarly to you can do with
2355 corefiles. You can select trace frames, print data that was
2356 collected in them, and use tstatus to display the state of the
2357 tracing run at the moment that it was saved. To create a trace
2358 file, use "tsave <filename>", and to use it, do "target tfile
2361 ** Circular trace buffer
2363 You can ask the target agent to handle the trace buffer as a
2364 circular buffer, discarding the oldest trace frames to make room for
2365 newer ones, by setting circular-trace-buffer to on. This feature may
2366 not be available for all target agents.
2371 The disassemble command, when invoked with two arguments, now requires
2372 the arguments to be comma-separated.
2375 The info variables command now displays variable definitions. Files
2376 which only declare a variable are not shown.
2379 The source command is now capable of sourcing Python scripts.
2380 This feature is dependent on the debugger being build with Python
2383 Related to this enhancement is also the introduction of a new command
2384 "set script-extension" (see below).
2386 * New commands (for set/show, see "New options" below)
2388 record save [<FILENAME>]
2389 Save a file (in core file format) containing the process record
2390 execution log for replay debugging at a later time.
2392 record restore <FILENAME>
2393 Restore the process record execution log that was saved at an
2394 earlier time, for replay debugging.
2396 add-inferior [-copies <N>] [-exec <FILENAME>]
2399 clone-inferior [-copies <N>] [ID]
2400 Make a new inferior ready to execute the same program another
2401 inferior has loaded.
2406 maint info program-spaces
2407 List the program spaces loaded into GDB.
2409 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2410 show remote interrupt-sequence
2411 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2412 as the sequence to the remote target in order to interrupt the execution.
2413 Ctrl-C is a default. Some system prefers BREAK which is high level of
2414 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2415 Magic SysRq g. It is BREAK signal and character 'g'.
2417 set remote interrupt-on-connect [on | off]
2418 show remote interrupt-on-connect
2419 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2420 remote target when gdb connects to it. This is needed when you debug
2423 set remotebreak [on | off]
2425 Deprecated. Use "set/show remote interrupt-sequence" instead.
2427 tvariable $NAME [ = EXP ]
2428 Create or modify a trace state variable.
2431 List trace state variables and their values.
2433 delete tvariable $NAME ...
2434 Delete one or more trace state variables.
2437 Evaluate the given expressions without collecting anything into the
2438 trace buffer. (Valid in tracepoint actions only.)
2440 ftrace FN / FILE:LINE / *ADDR
2441 Define a fast tracepoint at the given function, line, or address.
2443 * New expression syntax
2445 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2446 GDB now parses 0b101010 identically with 42.
2450 set follow-exec-mode new|same
2451 show follow-exec-mode
2452 Control whether GDB reuses the same inferior across an exec call or
2453 creates a new one. This is useful to be able to restart the old
2454 executable after the inferior having done an exec call.
2456 set default-collect EXPR, ...
2457 show default-collect
2458 Define a list of expressions to be collected at each tracepoint.
2459 This is a useful way to ensure essential items are not overlooked,
2460 such as registers or a critical global variable.
2462 set disconnected-tracing
2463 show disconnected-tracing
2464 If set to 1, the target is instructed to continue tracing if it
2465 loses its connection to GDB. If 0, the target is to stop tracing
2468 set circular-trace-buffer
2469 show circular-trace-buffer
2470 If set to on, the target is instructed to use a circular trace buffer
2471 and discard the oldest trace frames instead of stopping the trace due
2472 to a full trace buffer. If set to off, the trace stops when the buffer
2473 fills up. Some targets may not support this.
2475 set script-extension off|soft|strict
2476 show script-extension
2477 If set to "off", the debugger does not perform any script language
2478 recognition, and all sourced files are assumed to be GDB scripts.
2479 If set to "soft" (the default), files are sourced according to
2480 filename extension, falling back to GDB scripts if the first
2482 If set to "strict", files are sourced according to filename extension.
2484 set ada trust-PAD-over-XVS on|off
2485 show ada trust-PAD-over-XVS
2486 If off, activate a workaround against a bug in the debugging information
2487 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2488 the GCC sources for more information about the GNAT encoding and
2489 PAD types in particular). It is always safe to set this option to
2490 off, but this introduces a slight performance penalty. The default
2493 * Python API Improvements
2495 ** GDB provides the new class gdb.LazyString. This is useful in
2496 some pretty-printing cases. The new method gdb.Value.lazy_string
2497 provides a simple way to create objects of this type.
2499 ** The fields returned by gdb.Type.fields now have an
2500 `is_base_class' attribute.
2502 ** The new method gdb.Type.range returns the range of an array type.
2504 ** The new method gdb.parse_and_eval can be used to parse and
2505 evaluate an expression.
2507 * New remote packets
2510 Define a trace state variable.
2513 Get the current value of a trace state variable.
2516 Set desired tracing behavior upon disconnection.
2519 Set the trace buffer to be linear or circular.
2522 Get data about the tracepoints currently in use.
2526 Process record now works correctly with hardware watchpoints.
2528 Multiple bug fixes have been made to the mips-irix port, making it
2529 much more reliable. In particular:
2530 - Debugging threaded applications is now possible again. Previously,
2531 GDB would hang while starting the program, or while waiting for
2532 the program to stop at a breakpoint.
2533 - Attaching to a running process no longer hangs.
2534 - An error occurring while loading a core file has been fixed.
2535 - Changing the value of the PC register now works again. This fixes
2536 problems observed when using the "jump" command, or when calling
2537 a function from GDB, or even when assigning a new value to $pc.
2538 - With the "finish" and "return" commands, the return value for functions
2539 returning a small array is now correctly printed.
2540 - It is now possible to break on shared library code which gets executed
2541 during a shared library init phase (code executed while executing
2542 their .init section). Previously, the breakpoint would have no effect.
2543 - GDB is now able to backtrace through the signal handler for
2544 non-threaded programs.
2546 PIE (Position Independent Executable) programs debugging is now supported.
2547 This includes debugging execution of PIC (Position Independent Code) shared
2548 libraries although for that, it should be possible to run such libraries as an
2551 *** Changes in GDB 7.0
2553 * GDB now has an interface for JIT compilation. Applications that
2554 dynamically generate code can create symbol files in memory and register
2555 them with GDB. For users, the feature should work transparently, and
2556 for JIT developers, the interface is documented in the GDB manual in the
2557 "JIT Compilation Interface" chapter.
2559 * Tracepoints may now be conditional. The syntax is as for
2560 breakpoints; either an "if" clause appended to the "trace" command,
2561 or the "condition" command is available. GDB sends the condition to
2562 the target for evaluation using the same bytecode format as is used
2563 for tracepoint actions.
2565 * The disassemble command now supports: an optional /r modifier, print the
2566 raw instructions in hex as well as in symbolic form, and an optional /m
2567 modifier to print mixed source+assembly.
2569 * Process record and replay
2571 In a architecture environment that supports ``process record and
2572 replay'', ``process record and replay'' target can record a log of
2573 the process execution, and replay it with both forward and reverse
2576 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2577 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2578 set execution-direction {forward|reverse}, for targets that support
2581 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2582 feature is available with a native GDB running on kernel version
2585 * GDB now has support for multi-byte and wide character sets on the
2586 target. Strings whose character type is wchar_t, char16_t, or
2587 char32_t are now correctly printed. GDB supports wide- and unicode-
2588 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2589 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2590 `printf'. This feature requires iconv to work properly; if your
2591 system does not have a working iconv, GDB can use GNU libiconv. See
2592 the installation instructions for more information.
2594 * GDB now supports automatic retrieval of shared library files from
2595 remote targets. To use this feature, specify a system root that begins
2596 with the `remote:' prefix, either via the `set sysroot' command or via
2597 the `--with-sysroot' configure-time option.
2599 * "info sharedlibrary" now takes an optional regex of libraries to show,
2600 and it now reports if a shared library has no debugging information.
2602 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2603 now complete on file names.
2605 * When completing in expressions, gdb will attempt to limit
2606 completions to allowable structure or union fields, where appropriate.
2607 For instance, consider:
2609 # struct example { int f1; double f2; };
2610 # struct example variable;
2613 If the user types TAB at the end of this command line, the available
2614 completions will be "f1" and "f2".
2616 * Inlined functions are now supported. They show up in backtraces, and
2617 the "step", "next", and "finish" commands handle them automatically.
2619 * GDB now supports the token-splicing (##) and stringification (#)
2620 operators when expanding macros. It also supports variable-arity
2623 * GDB now supports inspecting extra signal information, exported by
2624 the new $_siginfo convenience variable. The feature is currently
2625 implemented on linux ARM, i386 and amd64.
2627 * GDB can now display the VFP floating point registers and NEON vector
2628 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2629 can provide these registers (requires Linux 2.6.30 or later). Remote
2630 and simulator targets may also provide them.
2632 * New remote packets
2635 Search memory for a sequence of bytes.
2638 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2639 operation over reliable transport links. Use of this packet is
2640 controlled by the `set remote noack-packet' command.
2643 Kill the process with the specified process ID. Use this in preference
2644 to `k' when multiprocess protocol extensions are supported.
2647 Obtains additional operating system information
2651 Read or write additional signal information.
2653 * Removed remote protocol undocumented extension
2655 An undocumented extension to the remote protocol's `S' stop reply
2656 packet that permited the stub to pass a process id was removed.
2657 Remote servers should use the `T' stop reply packet instead.
2659 * GDB now supports multiple function calling conventions according to the
2660 DWARF-2 DW_AT_calling_convention function attribute.
2662 * The SH target utilizes the aforementioned change to distinguish between gcc
2663 and Renesas calling convention. It also adds the new CLI commands
2664 `set/show sh calling-convention'.
2666 * GDB can now read compressed debug sections, as produced by GNU gold
2667 with the --compress-debug-sections=zlib flag.
2669 * 64-bit core files are now supported on AIX.
2671 * Thread switching is now supported on Tru64.
2673 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2674 which will be allocated using malloc later in program execution.
2676 * The qXfer:libraries:read remote procotol packet now allows passing a
2677 list of section offsets.
2679 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2680 conditions handling signals delivered during attach or thread creation
2681 have also been fixed.
2683 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2684 From the user's standpoint, all unqualified instances of True and False
2685 are treated as the standard definitions, regardless of context.
2687 * GDB now parses C++ symbol and type names more flexibly. For
2690 template<typename T> class C { };
2693 GDB will now correctly handle all of:
2695 ptype C<char const *>
2696 ptype C<char const*>
2697 ptype C<const char *>
2698 ptype C<const char*>
2700 * New features in the GDB remote stub, gdbserver
2702 - The "--wrapper" command-line argument tells gdbserver to use a
2703 wrapper program to launch programs for debugging.
2705 - On PowerPC and S/390 targets, it is now possible to use a single
2706 gdbserver executable to debug both 32-bit and 64-bit programs.
2707 (This requires gdbserver itself to be built as a 64-bit executable.)
2709 - gdbserver uses the new noack protocol mode for TCP connections to
2710 reduce communications latency, if also supported and enabled in GDB.
2712 - Support for the sparc64-linux-gnu target is now included in
2715 - The amd64-linux build of gdbserver now supports debugging both
2716 32-bit and 64-bit programs.
2718 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2719 now support hardware watchpoints, and will use them automatically
2724 GDB now has support for scripting using Python. Whether this is
2725 available is determined at configure time.
2727 New GDB commands can now be written in Python.
2729 * Ada tasking support
2731 Ada tasks can now be inspected in GDB. The following commands have
2735 Print the list of Ada tasks.
2737 Print detailed information about task number N.
2739 Print the task number of the current task.
2741 Switch the context of debugging to task number N.
2743 * Support for user-defined prefixed commands. The "define" command can
2744 add new commands to existing prefixes, e.g. "target".
2746 * Multi-inferior, multi-process debugging.
2748 GDB now has generalized support for multi-inferior debugging. See
2749 "Debugging Multiple Inferiors" in the manual for more information.
2750 Although availability still depends on target support, the command
2751 set is more uniform now. The GNU/Linux specific multi-forks support
2752 has been migrated to this new framework. This implied some user
2753 visible changes; see "New commands" and also "Removed commands"
2756 * Target descriptions can now describe the target OS ABI. See the
2757 "Target Description Format" section in the user manual for more
2760 * Target descriptions can now describe "compatible" architectures
2761 to indicate that the target can execute applications for a different
2762 architecture in addition to those for the main target architecture.
2763 See the "Target Description Format" section in the user manual for
2766 * Multi-architecture debugging.
2768 GDB now includes general supports for debugging applications on
2769 hybrid systems that use more than one single processor architecture
2770 at the same time. Each such hybrid architecture still requires
2771 specific support to be added. The only hybrid architecture supported
2772 in this version of GDB is the Cell Broadband Engine.
2774 * GDB now supports integrated debugging of Cell/B.E. applications that
2775 use both the PPU and SPU architectures. To enable support for hybrid
2776 Cell/B.E. debugging, you need to configure GDB to support both the
2777 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2778 --enable-targets configure option.
2780 * Non-stop mode debugging.
2782 For some targets, GDB now supports an optional mode of operation in
2783 which you can examine stopped threads while other threads continue
2784 to execute freely. This is referred to as non-stop mode, with the
2785 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2786 section in the user manual for more information.
2788 To be able to support remote non-stop debugging, a remote stub needs
2789 to implement the non-stop mode remote protocol extensions, as
2790 described in the "Remote Non-Stop" section of the user manual. The
2791 GDB remote stub, gdbserver, has been adjusted to support these
2792 extensions on linux targets.
2794 * New commands (for set/show, see "New options" below)
2796 catch syscall [NAME(S) | NUMBER(S)]
2797 Catch system calls. Arguments, which should be names of system
2798 calls or their numbers, mean catch only those syscalls. Without
2799 arguments, every syscall will be caught. When the inferior issues
2800 any of the specified syscalls, GDB will stop and announce the system
2801 call, both when it is called and when its call returns. This
2802 feature is currently available with a native GDB running on the
2803 Linux Kernel, under the following architectures: x86, x86_64,
2804 PowerPC and PowerPC64.
2806 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2808 Search memory for a sequence of bytes.
2810 maint set python print-stack
2811 maint show python print-stack
2812 Show a stack trace when an error is encountered in a Python script.
2815 Invoke CODE by passing it to the Python interpreter.
2820 These allow macros to be defined, undefined, and listed
2824 Show operating system information about processes.
2827 List the inferiors currently under GDB's control.
2830 Switch focus to inferior number NUM.
2833 Detach from inferior number NUM.
2836 Kill inferior number NUM.
2840 set spu stop-on-load
2841 show spu stop-on-load
2842 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2844 set spu auto-flush-cache
2845 show spu auto-flush-cache
2846 Control whether to automatically flush the software-managed cache
2847 during Cell/B.E. debugging.
2849 set sh calling-convention
2850 show sh calling-convention
2851 Control the calling convention used when calling SH target functions.
2854 show debug timestamp
2855 Control display of timestamps with GDB debugging output.
2857 set disassemble-next-line
2858 show disassemble-next-line
2859 Control display of disassembled source lines or instructions when
2862 set remote noack-packet
2863 show remote noack-packet
2864 Set/show the use of remote protocol QStartNoAckMode packet. See above
2865 under "New remote packets."
2867 set remote query-attached-packet
2868 show remote query-attached-packet
2869 Control use of remote protocol `qAttached' (query-attached) packet.
2871 set remote read-siginfo-object
2872 show remote read-siginfo-object
2873 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2876 set remote write-siginfo-object
2877 show remote write-siginfo-object
2878 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2881 set remote reverse-continue
2882 show remote reverse-continue
2883 Control use of remote protocol 'bc' (reverse-continue) packet.
2885 set remote reverse-step
2886 show remote reverse-step
2887 Control use of remote protocol 'bs' (reverse-step) packet.
2889 set displaced-stepping
2890 show displaced-stepping
2891 Control displaced stepping mode. Displaced stepping is a way to
2892 single-step over breakpoints without removing them from the debuggee.
2893 Also known as "out-of-line single-stepping".
2896 show debug displaced
2897 Control display of debugging info for displaced stepping.
2899 maint set internal-error
2900 maint show internal-error
2901 Control what GDB does when an internal error is detected.
2903 maint set internal-warning
2904 maint show internal-warning
2905 Control what GDB does when an internal warning is detected.
2910 Use a wrapper program to launch programs for debugging.
2912 set multiple-symbols (all|ask|cancel)
2913 show multiple-symbols
2914 The value of this variable can be changed to adjust the debugger behavior
2915 when an expression or a breakpoint location contains an ambiguous symbol
2916 name (an overloaded function name, for instance).
2918 set breakpoint always-inserted
2919 show breakpoint always-inserted
2920 Keep breakpoints always inserted in the target, as opposed to inserting
2921 them when resuming the target, and removing them when the target stops.
2922 This option can improve debugger performance on slow remote targets.
2924 set arm fallback-mode (arm|thumb|auto)
2925 show arm fallback-mode
2926 set arm force-mode (arm|thumb|auto)
2928 These commands control how ARM GDB determines whether instructions
2929 are ARM or Thumb. The default for both settings is auto, which uses
2930 the current CPSR value for instructions without symbols; previous
2931 versions of GDB behaved as if "set arm fallback-mode arm".
2933 set disable-randomization
2934 show disable-randomization
2935 Standalone programs run with the virtual address space randomization enabled
2936 by default on some platforms. This option keeps the addresses stable across
2937 multiple debugging sessions.
2941 Control whether other threads are stopped or not when some thread hits
2946 Requests that asynchronous execution is enabled in the target, if available.
2947 In this case, it's possible to resume target in the background, and interact
2948 with GDB while the target is running. "show target-async" displays the
2949 current state of asynchronous execution of the target.
2951 set target-wide-charset
2952 show target-wide-charset
2953 The target-wide-charset is the name of the character set that GDB
2954 uses when printing characters whose type is wchar_t.
2956 set tcp auto-retry (on|off)
2958 set tcp connect-timeout
2959 show tcp connect-timeout
2960 These commands allow GDB to retry failed TCP connections to a remote stub
2961 with a specified timeout period; this is useful if the stub is launched
2962 in parallel with GDB but may not be ready to accept connections immediately.
2964 set libthread-db-search-path
2965 show libthread-db-search-path
2966 Control list of directories which GDB will search for appropriate
2969 set schedule-multiple (on|off)
2970 show schedule-multiple
2971 Allow GDB to resume all threads of all processes or only threads of
2972 the current process.
2976 Use more aggressive caching for accesses to the stack. This improves
2977 performance of remote debugging (particularly backtraces) without
2978 affecting correctness.
2980 set interactive-mode (on|off|auto)
2981 show interactive-mode
2982 Control whether GDB runs in interactive mode (on) or not (off).
2983 When in interactive mode, GDB waits for the user to answer all
2984 queries. Otherwise, GDB does not wait and assumes the default
2985 answer. When set to auto (the default), GDB determines which
2986 mode to use based on the stdin settings.
2991 For program forks, this is replaced by the new more generic `info
2992 inferiors' command. To list checkpoints, you can still use the
2993 `info checkpoints' command, which was an alias for the `info forks'
2997 Replaced by the new `inferior' command. To switch between
2998 checkpoints, you can still use the `restart' command, which was an
2999 alias for the `fork' command.
3002 This is removed, since some targets don't have a notion of
3003 processes. To switch between processes, you can still use the
3004 `inferior' command using GDB's own inferior number.
3007 For program forks, this is replaced by the new more generic `kill
3008 inferior' command. To delete a checkpoint, you can still use the
3009 `delete checkpoint' command, which was an alias for the `delete
3013 For program forks, this is replaced by the new more generic `detach
3014 inferior' command. To detach a checkpoint, you can still use the
3015 `detach checkpoint' command, which was an alias for the `detach
3018 * New native configurations
3020 x86/x86_64 Darwin i[34567]86-*-darwin*
3022 x86_64 MinGW x86_64-*-mingw*
3026 Lattice Mico32 lm32-*
3027 x86 DICOS i[34567]86-*-dicos*
3028 x86_64 DICOS x86_64-*-dicos*
3031 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3032 (mingw32ce) debugging.
3038 These commands were actually not implemented on any target.
3040 *** Changes in GDB 6.8
3042 * New native configurations
3044 NetBSD/hppa hppa*-*netbsd*
3045 Xtensa GNU/Linux xtensa*-*-linux*
3049 NetBSD/hppa hppa*-*-netbsd*
3050 Xtensa GNU/Lunux xtensa*-*-linux*
3052 * Change in command line behavior -- corefiles vs. process ids.
3054 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3055 attaching to process NUMBER fails, GDB no longer attempts to open a
3056 core file named NUMBER. Attaching to a program using the -c option
3057 is no longer supported. Instead, use the '-p' or '--pid' options.
3059 * GDB can now be built as a native debugger for debugging Windows x86
3060 (mingw32) Portable Executable (PE) programs.
3062 * Pending breakpoints no longer change their number when their address
3065 * GDB now supports breakpoints with multiple locations,
3066 including breakpoints on C++ constructors, inside C++ templates,
3067 and in inlined functions.
3069 * GDB's ability to debug optimized code has been improved. GDB more
3070 accurately identifies function bodies and lexical blocks that occupy
3071 more than one contiguous range of addresses.
3073 * Target descriptions can now describe registers for PowerPC.
3075 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3076 registers on PowerPC targets.
3078 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3079 targets even when the libthread_db library is not available.
3081 * The GDB remote stub, gdbserver, now supports the new file transfer
3082 commands (remote put, remote get, and remote delete).
3084 * The GDB remote stub, gdbserver, now supports run and attach in
3085 extended-remote mode.
3087 * hppa*64*-*-hpux11* target broken
3088 The debugger is unable to start a program and fails with the following
3089 error: "Error trying to get information about dynamic linker".
3090 The gdb-6.7 release is also affected.
3092 * GDB now supports the --enable-targets= configure option to allow
3093 building a single GDB executable that supports multiple remote
3094 target architectures.
3096 * GDB now supports debugging C and C++ programs which use the
3097 Decimal Floating Point extension. In addition, the PowerPC target
3098 now has a set of pseudo-registers to inspect decimal float values
3099 stored in two consecutive float registers.
3101 * The -break-insert MI command can optionally create pending
3104 * Improved support for debugging Ada
3105 Many improvements to the Ada language support have been made. These
3107 - Better support for Ada2005 interface types
3108 - Improved handling of arrays and slices in general
3109 - Better support for Taft-amendment types
3110 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3112 - Improved command completion in Ada
3115 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3120 set print frame-arguments (all|scalars|none)
3121 show print frame-arguments
3122 The value of this variable can be changed to control which argument
3123 values should be printed by the debugger when displaying a frame.
3128 Transfer files to and from a remote target, and delete remote files.
3135 Transfer files to and from a remote target, and delete remote files.
3137 * New remote packets
3144 Open, close, read, write, and delete files on the remote system.
3147 Attach to an existing process on the remote system, in extended-remote
3151 Run a new process on the remote system, in extended-remote mode.
3153 *** Changes in GDB 6.7
3155 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3156 bfd, libiberty and opcodes, as revealed by static analysis donated by
3157 Coverity, Inc. (http://scan.coverity.com).
3159 * When looking up multiply-defined global symbols, GDB will now prefer the
3160 symbol definition in the current shared library if it was built using the
3161 -Bsymbolic linker option.
3163 * When the Text User Interface (TUI) is not configured, GDB will now
3164 recognize the -tui command-line option and print a message that the TUI
3167 * The GDB remote stub, gdbserver, now has lower overhead for high
3168 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3170 * GDB for MIPS targets now autodetects whether a remote target provides
3171 32-bit or 64-bit register values.
3173 * Support for C++ member pointers has been improved.
3175 * GDB now understands XML target descriptions, which specify the
3176 target's overall architecture. GDB can read a description from
3177 a local file or over the remote serial protocol.
3179 * Vectors of single-byte data use a new integer type which is not
3180 automatically displayed as character or string data.
3182 * The /s format now works with the print command. It displays
3183 arrays of single-byte integers and pointers to single-byte integers
3186 * Target descriptions can now describe target-specific registers,
3187 for architectures which have implemented the support (currently
3188 only ARM, M68K, and MIPS).
3190 * GDB and the GDB remote stub, gdbserver, now support the XScale
3193 * The GDB remote stub, gdbserver, has been updated to support
3194 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3195 has been rewritten to use the standard GDB remote protocol.
3197 * GDB can now step into C++ functions which are called through thunks.
3199 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3201 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3202 layout. It also supports a TextSeg= and DataSeg= response when only
3203 segment base addresses (rather than offsets) are available.
3205 * The /i format now outputs any trailing branch delay slot instructions
3206 immediately following the last instruction within the count specified.
3208 * The GDB remote protocol "T" stop reply packet now supports a
3209 "library" response. Combined with the new "qXfer:libraries:read"
3210 packet, this response allows GDB to debug shared libraries on targets
3211 where the operating system manages the list of loaded libraries (e.g.
3212 Windows and SymbianOS).
3214 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3215 (DLLs) on Windows and Windows CE targets.
3217 * GDB now supports a faster verification that a .debug file matches its binary
3218 according to its build-id signature, if the signature is present.
3224 Enable or disable hardware flow control (RTS/CTS) on the serial port
3225 when debugging using remote targets.
3227 set mem inaccessible-by-default
3228 show mem inaccessible-by-default
3229 If the target supplies a memory map, for instance via the remote
3230 protocol's "qXfer:memory-map:read" packet, setting this variable
3231 prevents GDB from accessing memory outside the memory map. This
3232 is useful for targets with memory mapped registers or which react
3233 badly to accesses of unmapped address space.
3235 set breakpoint auto-hw
3236 show breakpoint auto-hw
3237 If the target supplies a memory map, for instance via the remote
3238 protocol's "qXfer:memory-map:read" packet, setting this variable
3239 lets GDB use hardware breakpoints automatically for memory regions
3240 where it can not use software breakpoints. This covers both the
3241 "break" command and internal breakpoints used for other commands
3242 including "next" and "finish".
3245 catch exception unhandled
3246 Stop the program execution when Ada exceptions are raised.
3249 Stop the program execution when an Ada assertion failed.
3253 Set an alternate system root for target files. This is a more
3254 general version of "set solib-absolute-prefix", which is now
3255 an alias to "set sysroot".
3258 Provide extended SPU facility status information. This set of
3259 commands is available only when debugging the Cell/B.E. SPU
3262 * New native configurations
3264 OpenBSD/sh sh*-*openbsd*
3267 unset tdesc filename
3269 Use the specified local file as an XML target description, and do
3270 not query the target for its built-in description.
3274 OpenBSD/sh sh*-*-openbsd*
3275 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3276 Toshiba Media Processor mep-elf
3278 * New remote packets
3281 Ignore the specified signals; pass them directly to the debugged program
3282 without stopping other threads or reporting them to GDB.
3284 qXfer:features:read:
3285 Read an XML target description from the target, which describes its
3290 Read or write contents of an spufs file on the target system. These
3291 packets are available only on the Cell/B.E. SPU architecture.
3293 qXfer:libraries:read:
3294 Report the loaded shared libraries. Combined with new "T" packet
3295 response, this packet allows GDB to debug shared libraries on
3296 targets where the operating system manages the list of loaded
3297 libraries (e.g. Windows and SymbianOS).
3301 Support for these obsolete configurations has been removed.
3309 i[34567]86-*-lynxos*
3310 i[34567]86-*-netware*
3311 i[34567]86-*-sco3.2v5*
3312 i[34567]86-*-sco3.2v4*
3314 i[34567]86-*-sysv4.2*
3317 i[34567]86-*-unixware2*
3318 i[34567]86-*-unixware*
3327 * Other removed features
3334 Various m68k-only ROM monitors.
3341 Various Renesas ROM monitors and debugging interfaces for SH and
3346 Support for a Macraigor serial interface to on-chip debugging.
3347 GDB does not directly support the newer parallel or USB
3352 A debug information format. The predecessor to DWARF 2 and
3353 DWARF 3, which are still supported.
3355 Support for the HP aCC compiler on HP-UX/PA-RISC
3357 SOM-encapsulated symbolic debugging information, automatic
3358 invocation of pxdb, and the aCC custom C++ ABI. This does not
3359 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3360 with aCC can still be debugged on an assembly level.
3362 MIPS ".pdr" sections
3364 A MIPS-specific format used to describe stack frame layout
3365 in debugging information.
3369 GDB could work with an older version of Guile to debug
3370 the interpreter and Scheme programs running in it.
3372 set mips stack-arg-size
3373 set mips saved-gpreg-size
3375 Use "set mips abi" to control parameter passing for MIPS.
3377 *** Changes in GDB 6.6
3382 Cell Broadband Engine SPU spu-elf
3384 * GDB can now be configured as a cross-debugger targeting native Windows
3385 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3386 running on a Windows system over TCP/IP to debug Windows programs.
3388 * The GDB remote stub, gdbserver, has been updated to support Windows and
3389 Cygwin debugging. Both single-threaded and multi-threaded programs are
3392 * The "set trust-readonly-sections" command works again. This command was
3393 broken in GDB 6.3, 6.4, and 6.5.
3395 * The "load" command now supports writing to flash memory, if the remote
3396 stub provides the required support.
3398 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3399 longer requires symbolic debug information (e.g. DWARF-2).
3404 unset substitute-path
3405 show substitute-path
3406 Manage a list of substitution rules that GDB uses to rewrite the name
3407 of the directories where the sources are located. This can be useful
3408 for instance when the sources were moved to a different location
3409 between compilation and debugging.
3413 Print each CLI command as it is executed. Each command is prefixed with
3414 a number of `+' symbols representing the nesting depth.
3415 The source command now has a `-v' option to enable the same feature.
3419 The ARM Demon monitor support (RDP protocol, "target rdp").
3421 Kernel Object Display, an embedded debugging feature which only worked with
3422 an obsolete version of Cisco IOS.
3424 The 'set download-write-size' and 'show download-write-size' commands.
3426 * New remote packets
3429 Tell a stub about GDB client features, and request remote target features.
3430 The first feature implemented is PacketSize, which allows the target to
3431 specify the size of packets it can handle - to minimize the number of
3432 packets required and improve performance when connected to a remote
3436 Fetch an OS auxilliary vector from the remote stub. This packet is a
3437 more efficient replacement for qPart:auxv:read.
3439 qXfer:memory-map:read:
3440 Fetch a memory map from the remote stub, including information about
3441 RAM, ROM, and flash memory devices.
3446 Erase and program a flash memory device.
3448 * Removed remote packets
3451 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3452 used it, and only gdbserver implemented it.
3454 *** Changes in GDB 6.5
3458 Renesas M32C/M16C m32c-elf
3460 Morpho Technologies ms1 ms1-elf
3464 init-if-undefined Initialize a convenience variable, but
3465 only if it doesn't already have a value.
3467 The following commands are presently only implemented for native GNU/Linux:
3469 checkpoint Save a snapshot of the program state.
3471 restart <n> Return the program state to a
3472 previously saved state.
3474 info checkpoints List currently saved checkpoints.
3476 delete-checkpoint <n> Delete a previously saved checkpoint.
3478 set|show detach-on-fork Tell gdb whether to detach from a newly
3479 forked process, or to keep debugging it.
3481 info forks List forks of the user program that
3482 are available to be debugged.
3484 fork <n> Switch to debugging one of several
3485 forks of the user program that are
3486 available to be debugged.
3488 delete-fork <n> Delete a fork from the list of forks
3489 that are available to be debugged (and
3490 kill the forked process).
3492 detach-fork <n> Delete a fork from the list of forks
3493 that are available to be debugged (and
3494 allow the process to continue).
3498 Morpho Technologies ms2 ms1-elf
3500 * Improved Windows host support
3502 GDB now builds as a cross debugger hosted on i686-mingw32, including
3503 native console support, and remote communications using either
3504 network sockets or serial ports.
3506 * Improved Modula-2 language support
3508 GDB can now print most types in the Modula-2 syntax. This includes:
3509 basic types, set types, record types, enumerated types, range types,
3510 pointer types and ARRAY types. Procedure var parameters are correctly
3511 printed and hexadecimal addresses and character constants are also
3512 written in the Modula-2 syntax. Best results can be obtained by using
3513 GNU Modula-2 together with the -gdwarf-2 command line option.
3517 The ARM rdi-share module.
3519 The Netware NLM debug server.
3521 *** Changes in GDB 6.4
3523 * New native configurations
3525 OpenBSD/arm arm*-*-openbsd*
3526 OpenBSD/mips64 mips64-*-openbsd*
3530 Morpho Technologies ms1 ms1-elf
3532 * New command line options
3534 --batch-silent As for --batch, but totally silent.
3535 --return-child-result The debugger will exist with the same value
3536 the child (debugged) program exited with.
3537 --eval-command COMMAND, -ex COMMAND
3538 Execute a single GDB CLI command. This may be
3539 specified multiple times and in conjunction
3540 with the --command (-x) option.
3542 * Deprecated commands removed
3544 The following commands, that were deprecated in 2000, have been
3548 set|show arm disassembly-flavor set|show arm disassembler
3549 othernames set arm disassembler
3550 set|show remotedebug set|show debug remote
3551 set|show archdebug set|show debug arch
3552 set|show eventdebug set|show debug event
3555 * New BSD user-level threads support
3557 It is now possible to debug programs using the user-level threads
3558 library on OpenBSD and FreeBSD. Currently supported (target)
3561 FreeBSD/amd64 x86_64-*-freebsd*
3562 FreeBSD/i386 i386-*-freebsd*
3563 OpenBSD/i386 i386-*-openbsd*
3565 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3566 are not yet supported.
3568 * New support for Matsushita MN10300 w/sim added
3569 (Work in progress). mn10300-elf.
3571 * REMOVED configurations and files
3573 VxWorks and the XDR protocol *-*-vxworks
3574 Motorola MCORE mcore-*-*
3575 National Semiconductor NS32000 ns32k-*-*
3577 * New "set print array-indexes" command
3579 After turning this setting "on", GDB prints the index of each element
3580 when displaying arrays. The default is "off" to preserve the previous
3583 * VAX floating point support
3585 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3587 * User-defined command support
3589 In addition to using $arg0..$arg9 for argument passing, it is now possible
3590 to use $argc to determine now many arguments have been passed. See the
3591 section on user-defined commands in the user manual for more information.
3593 *** Changes in GDB 6.3:
3595 * New command line option
3597 GDB now accepts -l followed by a number to set the timeout for remote
3600 * GDB works with GCC -feliminate-dwarf2-dups
3602 GDB now supports a more compact representation of DWARF-2 debug
3603 information using DW_FORM_ref_addr references. These are produced
3604 by GCC with the option -feliminate-dwarf2-dups and also by some
3605 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3606 to use -feliminate-dwarf2-dups.
3608 * Internationalization
3610 When supported by the host system, GDB will be built with
3611 internationalization (libintl). The task of marking up the sources is
3612 continued, we're looking forward to our first translation.
3616 Initial support for debugging programs compiled with the GNAT
3617 implementation of the Ada programming language has been integrated
3618 into GDB. In this release, support is limited to expression evaluation.
3620 * New native configurations
3622 GNU/Linux/m32r m32r-*-linux-gnu
3626 GDB's remote protocol now includes support for the 'p' packet. This
3627 packet is used to fetch individual registers from a remote inferior.
3629 * END-OF-LIFE registers[] compatibility module
3631 GDB's internal register infrastructure has been completely rewritten.
3632 The new infrastructure making possible the implementation of key new
3633 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3636 GDB 6.3 will be the last release to include the the registers[]
3637 compatibility module that allowed out-of-date configurations to
3638 continue to work. This change directly impacts the following
3648 powerpc bdm protocol
3650 Unless there is activity to revive these configurations, they will be
3651 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3653 * OBSOLETE configurations and files
3655 Configurations that have been declared obsolete in this release have
3656 been commented out. Unless there is activity to revive these
3657 configurations, the next release of GDB will have their sources
3658 permanently REMOVED.
3667 *** Changes in GDB 6.2.1:
3669 * MIPS `break main; run' gave an heuristic-fence-post warning
3671 When attempting to run even a simple program, a warning about
3672 heuristic-fence-post being hit would be reported. This problem has
3675 * MIPS IRIX 'long double' crashed GDB
3677 When examining a long double variable, GDB would get a segmentation
3678 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3679 IRIX long double values).
3683 A bug in the VAX stack code was causing problems with the "next"
3684 command. This problem has been fixed.
3686 *** Changes in GDB 6.2:
3688 * Fix for ``many threads''
3690 On GNU/Linux systems that use the NPTL threads library, a program
3691 rapidly creating and deleting threads would confuse GDB leading to the
3694 ptrace: No such process.
3695 thread_db_get_info: cannot get thread info: generic error
3697 This problem has been fixed.
3699 * "-async" and "-noasync" options removed.
3701 Support for the broken "-noasync" option has been removed (it caused
3704 * New ``start'' command.
3706 This command runs the program until the begining of the main procedure.
3708 * New BSD Kernel Data Access Library (libkvm) interface
3710 Using ``target kvm'' it is now possible to debug kernel core dumps and
3711 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3712 platforms. Currently supported (native-only) configurations are:
3714 FreeBSD/amd64 x86_64-*-freebsd*
3715 FreeBSD/i386 i?86-*-freebsd*
3716 NetBSD/i386 i?86-*-netbsd*
3717 NetBSD/m68k m68*-*-netbsd*
3718 NetBSD/sparc sparc-*-netbsd*
3719 OpenBSD/amd64 x86_64-*-openbsd*
3720 OpenBSD/i386 i?86-*-openbsd*
3721 OpenBSD/m68k m68*-openbsd*
3722 OpenBSD/sparc sparc-*-openbsd*
3724 * Signal trampoline code overhauled
3726 Many generic problems with GDB's signal handling code have been fixed.
3727 These include: backtraces through non-contiguous stacks; recognition
3728 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3729 call; backtrace through a signal trampoline; step into and out of
3730 signal handlers; and single-stepping in the signal trampoline.
3732 Please note that kernel bugs are a limiting factor here. These
3733 features have been shown to work on an s390 GNU/Linux system that
3734 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3736 * Cygwin support for DWARF 2 added.
3738 * New native configurations
3740 GNU/Linux/hppa hppa*-*-linux*
3741 OpenBSD/hppa hppa*-*-openbsd*
3742 OpenBSD/m68k m68*-*-openbsd*
3743 OpenBSD/m88k m88*-*-openbsd*
3744 OpenBSD/powerpc powerpc-*-openbsd*
3745 NetBSD/vax vax-*-netbsd*
3746 OpenBSD/vax vax-*-openbsd*
3748 * END-OF-LIFE frame compatibility module
3750 GDB's internal frame infrastructure has been completely rewritten.
3751 The new infrastructure making it possible to support key new features
3752 including DWARF 2 Call Frame Information. To aid in the task of
3753 migrating old configurations to this new infrastructure, a
3754 compatibility module, that allowed old configurations to continue to
3755 work, was also included.
3757 GDB 6.2 will be the last release to include this frame compatibility
3758 module. This change directly impacts the following configurations:
3768 Unless there is activity to revive these configurations, they will be
3769 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3771 * REMOVED configurations and files
3773 Sun 3, running SunOS 3 m68*-*-sunos3*
3774 Sun 3, running SunOS 4 m68*-*-sunos4*
3775 Sun 2, running SunOS 3 m68000-*-sunos3*
3776 Sun 2, running SunOS 4 m68000-*-sunos4*
3777 Motorola 680x0 running LynxOS m68*-*-lynxos*
3778 AT&T 3b1/Unix pc m68*-att-*
3779 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3780 decstation mips-dec-* mips-little-*
3781 riscos mips-*-riscos* mips-*-sysv*
3782 sonymips mips-sony-*
3783 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3785 *** Changes in GDB 6.1.1:
3787 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3789 The TUI (Text-mode User Interface) is now built as part of a default
3790 GDB configuration. It is enabled by either selecting the TUI with the
3791 command line option "-i=tui" or by running the separate "gdbtui"
3792 program. For more information on the TUI, see the manual "Debugging
3795 * Pending breakpoint support (also included in GDB 6.1)
3797 Support has been added to allow you to specify breakpoints in shared
3798 libraries that have not yet been loaded. If a breakpoint location
3799 cannot be found, and the "breakpoint pending" option is set to auto,
3800 GDB queries you if you wish to make the breakpoint pending on a future
3801 shared-library load. If and when GDB resolves the breakpoint symbol,
3802 the pending breakpoint is removed as one or more regular breakpoints
3805 Pending breakpoints are very useful for GCJ Java debugging.
3807 * Fixed ISO-C build problems
3809 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3810 non ISO-C code that stopped them being built using a more strict ISO-C
3811 compiler (e.g., IBM's C compiler).
3813 * Fixed build problem on IRIX 5
3815 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3816 wasn't able to compile compile on an IRIX 5 system.
3818 * Added execute permission to gdb/gdbserver/configure
3820 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3821 permission. This bug would cause configure to fail on a number of
3822 systems (Solaris, IRIX). Ref: server/519.
3824 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3826 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3827 has been updated to use constant array sizes.
3829 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3831 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3832 its generated DWARF Call Frame Info. This encoding was causing GDB to
3833 panic, that panic has been fixed. Ref: gdb/1628.
3835 * Fixed a problem when examining parameters in shared library code.
3837 When examining parameters in optimized shared library code generated
3838 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3839 not available''. GDB now correctly displays the variable's value.
3841 *** Changes in GDB 6.1:
3843 * Removed --with-mmalloc
3845 Support for the mmalloc memory manager has been removed, as it
3846 conflicted with the internal gdb byte cache.
3848 * Changes in AMD64 configurations
3850 The AMD64 target now includes the %cs and %ss registers. As a result
3851 the AMD64 remote protocol has changed; this affects the floating-point
3852 and SSE registers. If you rely on those registers for your debugging,
3853 you should upgrade gdbserver on the remote side.
3855 * Revised SPARC target
3857 The SPARC target has been completely revised, incorporating the
3858 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3859 support for LynxOS and SunOS 4 has been dropped. Calling functions
3860 from within GDB on operating systems with a non-executable stack
3861 (Solaris, OpenBSD) now works.
3865 GDB has a new C++ demangler which does a better job on the mangled
3866 names generated by current versions of g++. It also runs faster, so
3867 with this and other changes gdb should now start faster on large C++
3870 * DWARF 2 Location Expressions
3872 GDB support for location expressions has been extended to support function
3873 arguments and frame bases. Older versions of GDB could crash when they
3876 * C++ nested types and namespaces
3878 GDB's support for nested types and namespaces in C++ has been
3879 improved, especially if you use the DWARF 2 debugging format. (This
3880 is the default for recent versions of GCC on most platforms.)
3881 Specifically, if you have a class "Inner" defined within a class or
3882 namespace "Outer", then GDB realizes that the class's name is
3883 "Outer::Inner", not simply "Inner". This should greatly reduce the
3884 frequency of complaints about not finding RTTI symbols. In addition,
3885 if you are stopped at inside of a function defined within a namespace,
3886 GDB modifies its name lookup accordingly.
3888 * New native configurations
3890 NetBSD/amd64 x86_64-*-netbsd*
3891 OpenBSD/amd64 x86_64-*-openbsd*
3892 OpenBSD/alpha alpha*-*-openbsd*
3893 OpenBSD/sparc sparc-*-openbsd*
3894 OpenBSD/sparc64 sparc64-*-openbsd*
3896 * New debugging protocols
3898 M32R with SDI protocol m32r-*-elf*
3900 * "set prompt-escape-char" command deleted.
3902 The command "set prompt-escape-char" has been deleted. This command,
3903 and its very obscure effet on GDB's prompt, was never documented,
3904 tested, nor mentioned in the NEWS file.
3906 * OBSOLETE configurations and files
3908 Configurations that have been declared obsolete in this release have
3909 been commented out. Unless there is activity to revive these
3910 configurations, the next release of GDB will have their sources
3911 permanently REMOVED.
3913 Sun 3, running SunOS 3 m68*-*-sunos3*
3914 Sun 3, running SunOS 4 m68*-*-sunos4*
3915 Sun 2, running SunOS 3 m68000-*-sunos3*
3916 Sun 2, running SunOS 4 m68000-*-sunos4*
3917 Motorola 680x0 running LynxOS m68*-*-lynxos*
3918 AT&T 3b1/Unix pc m68*-att-*
3919 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3920 decstation mips-dec-* mips-little-*
3921 riscos mips-*-riscos* mips-*-sysv*
3922 sonymips mips-sony-*
3923 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3925 * REMOVED configurations and files
3927 SGI Irix-4.x mips-sgi-irix4 or iris4
3928 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3929 Z8000 simulator z8k-zilog-none or z8ksim
3930 Matsushita MN10200 w/simulator mn10200-*-*
3931 H8/500 simulator h8500-hitachi-hms or h8500hms
3932 HP/PA running BSD hppa*-*-bsd*
3933 HP/PA running OSF/1 hppa*-*-osf*
3934 HP/PA Pro target hppa*-*-pro*
3935 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3936 386BSD i[3456]86-*-bsd*
3937 Sequent family i[3456]86-sequent-sysv4*
3938 i[3456]86-sequent-sysv*
3939 i[3456]86-sequent-bsd*
3940 SPARC running LynxOS sparc-*-lynxos*
3941 SPARC running SunOS 4 sparc-*-sunos4*
3942 Tsqware Sparclet sparclet-*-*
3943 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3945 *** Changes in GDB 6.0:
3949 Support for debugging the Objective-C programming language has been
3950 integrated into GDB.
3952 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3954 DWARF 2's Call Frame Information makes available compiler generated
3955 information that more exactly describes the program's run-time stack.
3956 By using this information, GDB is able to provide more robust stack
3959 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3960 have been updated to use a new backtrace mechanism which includes
3961 DWARF 2 CFI support.
3965 GDB's remote protocol has been extended to include support for hosted
3966 file I/O (where the remote target uses GDB's file system). See GDB's
3967 remote protocol documentation for details.
3969 * All targets using the new architecture framework.
3971 All of GDB's targets have been updated to use the new internal
3972 architecture framework. The way is now open for future GDB releases
3973 to include cross-architecture native debugging support (i386 on amd64,
3976 * GNU/Linux's Thread Local Storage (TLS)
3978 GDB now includes support for for the GNU/Linux implementation of
3979 per-thread variables.
3981 * GNU/Linux's Native POSIX Thread Library (NPTL)
3983 GDB's thread code has been updated to work with either the new
3984 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3986 * Separate debug info.
3988 GDB, in conjunction with BINUTILS, now supports a mechanism for
3989 automatically loading debug information from a separate file. Instead
3990 of shipping full debug and non-debug versions of system libraries,
3991 system integrators can now instead ship just the stripped libraries
3992 and optional debug files.
3994 * DWARF 2 Location Expressions
3996 DWARF 2 Location Expressions allow the compiler to more completely
3997 describe the location of variables (even in optimized code) to the
4000 GDB now includes preliminary support for location expressions (support
4001 for DW_OP_piece is still missing).
4005 A number of long standing bugs that caused GDB to die while starting a
4006 Java application have been fixed. GDB's Java support is now
4007 considered "useable".
4009 * GNU/Linux support for fork, vfork, and exec.
4011 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4012 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4015 * GDB supports logging output to a file
4017 There are two new commands, "set logging" and "show logging", which can be
4018 used to capture GDB's output to a file.
4020 * The meaning of "detach" has changed for gdbserver
4022 The "detach" command will now resume the application, as documented. To
4023 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4026 * d10v, m68hc11 `regs' command deprecated
4028 The `info registers' command has been updated so that it displays the
4029 registers using a format identical to the old `regs' command.
4033 A new command, "maint set profile on/off", has been added. This command can
4034 be used to enable or disable profiling while running GDB, to profile a
4035 session or a set of commands. In addition there is a new configure switch,
4036 "--enable-profiling", which will cause GDB to be compiled with profiling
4037 data, for more informative profiling results.
4039 * Default MI syntax changed to "mi2".
4041 The default MI (machine interface) syntax, enabled by the command line
4042 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4043 "mi1", can be enabled by specifying the option "-i=mi1".
4045 Support for the original "mi0" syntax (included in GDB 5.0) has been
4048 Fix for gdb/192: removed extraneous space when displaying frame level.
4049 Fix for gdb/672: update changelist is now output in mi list format.
4050 Fix for gdb/702: a -var-assign that updates the value now shows up
4051 in a subsequent -var-update.
4053 * New native configurations.
4055 FreeBSD/amd64 x86_64-*-freebsd*
4057 * Multi-arched targets.
4059 HP/PA HPUX11 hppa*-*-hpux*
4060 Renesas M32R/D w/simulator m32r-*-elf*
4062 * OBSOLETE configurations and files
4064 Configurations that have been declared obsolete in this release have
4065 been commented out. Unless there is activity to revive these
4066 configurations, the next release of GDB will have their sources
4067 permanently REMOVED.
4069 Z8000 simulator z8k-zilog-none or z8ksim
4070 Matsushita MN10200 w/simulator mn10200-*-*
4071 H8/500 simulator h8500-hitachi-hms or h8500hms
4072 HP/PA running BSD hppa*-*-bsd*
4073 HP/PA running OSF/1 hppa*-*-osf*
4074 HP/PA Pro target hppa*-*-pro*
4075 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4076 Sequent family i[3456]86-sequent-sysv4*
4077 i[3456]86-sequent-sysv*
4078 i[3456]86-sequent-bsd*
4079 Tsqware Sparclet sparclet-*-*
4080 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4082 * REMOVED configurations and files
4085 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4086 IBM AIX PS/2 i[3456]86-*-aix
4087 i386 running Mach 3.0 i[3456]86-*-mach3*
4088 i386 running Mach i[3456]86-*-mach*
4089 i386 running OSF/1 i[3456]86-*osf1mk*
4090 HP/Apollo 68k Family m68*-apollo*-sysv*,
4092 m68*-hp-bsd*, m68*-hp-hpux*
4093 Argonaut Risc Chip (ARC) arc-*-*
4094 Mitsubishi D30V d30v-*-*
4095 Fujitsu FR30 fr30-*-elf*
4096 OS/9000 i[34]86-*-os9k
4097 I960 with MON960 i960-*-coff
4099 * MIPS $fp behavior changed
4101 The convenience variable $fp, for the MIPS, now consistently returns
4102 the address of the current frame's base. Previously, depending on the
4103 context, $fp could refer to either $sp or the current frame's base
4104 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4105 The GNU Source-Level Debugger''.
4107 *** Changes in GDB 5.3:
4109 * GNU/Linux shared library multi-threaded performance improved.
4111 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4112 `/proc', in preference to `ptrace' for memory reads. This may result
4113 in an improvement in the start-up time of multi-threaded, shared
4114 library applications when run under GDB. One GDB user writes: ``loads
4115 shared libs like mad''.
4117 * ``gdbserver'' now supports multi-threaded applications on some targets
4119 Support for debugging multi-threaded applications which use
4120 the GNU/Linux LinuxThreads package has been added for
4121 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4122 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4124 * GDB now supports C/C++ preprocessor macros.
4126 GDB now expands preprocessor macro invocations in C/C++ expressions,
4127 and provides various commands for showing macro definitions and how
4130 The new command `macro expand EXPRESSION' expands any macro
4131 invocations in expression, and shows the result.
4133 The new command `show macro MACRO-NAME' shows the definition of the
4134 macro named MACRO-NAME, and where it was defined.
4136 Most compilers don't include information about macros in the debugging
4137 information by default. In GCC 3.1, for example, you need to compile
4138 your program with the options `-gdwarf-2 -g3'. If the macro
4139 information is present in the executable, GDB will read it.
4141 * Multi-arched targets.
4143 DEC Alpha (partial) alpha*-*-*
4144 DEC VAX (partial) vax-*-*
4146 National Semiconductor NS32000 (partial) ns32k-*-*
4147 Motorola 68000 (partial) m68k-*-*
4148 Motorola MCORE mcore-*-*
4152 Fujitsu FRV architecture added by Red Hat frv*-*-*
4155 * New native configurations
4157 Alpha NetBSD alpha*-*-netbsd*
4158 SH NetBSD sh*-*-netbsdelf*
4159 MIPS NetBSD mips*-*-netbsd*
4160 UltraSPARC NetBSD sparc64-*-netbsd*
4162 * OBSOLETE configurations and files
4164 Configurations that have been declared obsolete in this release have
4165 been commented out. Unless there is activity to revive these
4166 configurations, the next release of GDB will have their sources
4167 permanently REMOVED.
4169 Mitsubishi D30V d30v-*-*
4170 OS/9000 i[34]86-*-os9k
4171 IBM AIX PS/2 i[3456]86-*-aix
4172 Fujitsu FR30 fr30-*-elf*
4173 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4174 Argonaut Risc Chip (ARC) arc-*-*
4175 i386 running Mach 3.0 i[3456]86-*-mach3*
4176 i386 running Mach i[3456]86-*-mach*
4177 i386 running OSF/1 i[3456]86-*osf1mk*
4178 HP/Apollo 68k Family m68*-apollo*-sysv*,
4180 m68*-hp-bsd*, m68*-hp-hpux*
4181 I960 with MON960 i960-*-coff
4183 * OBSOLETE languages
4185 CHILL, a Pascal like language used by telecommunications companies.
4187 * REMOVED configurations and files
4189 AMD 29k family via UDI a29k-amd-udi, udi29k
4190 A29K VxWorks a29k-*-vxworks
4191 AMD 29000 embedded, using EBMON a29k-none-none
4192 AMD 29000 embedded with COFF a29k-none-coff
4193 AMD 29000 embedded with a.out a29k-none-aout
4195 testsuite/gdb.hp/gdb.threads-hp/ directory
4197 * New command "set max-user-call-depth <nnn>"
4199 This command allows the user to limit the call depth of user-defined
4200 commands. The default is 1024.
4202 * Changes in FreeBSD/i386 native debugging.
4204 Support for the "generate-core-file" has been added.
4206 * New commands "dump", "append", and "restore".
4208 These commands allow data to be copied from target memory
4209 to a bfd-format or binary file (dump and append), and back
4210 from a file into memory (restore).
4212 * Improved "next/step" support on multi-processor Alpha Tru64.
4214 The previous single-step mechanism could cause unpredictable problems,
4215 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4216 of a software single-step mechanism prevents this.
4218 *** Changes in GDB 5.2.1:
4226 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4227 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4228 Fix, by Joel Brobecker imported from mainline.
4230 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4231 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4232 Fix, by Fred Fish, imported from mainline.
4234 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4235 Surprisingly enough, it works now.
4236 By Michal Ludvig, imported from mainline.
4238 i386 hardware watchpoint support:
4239 avoid misses on second run for some targets.
4240 By Pierre Muller, imported from mainline.
4242 *** Changes in GDB 5.2:
4244 * New command "set trust-readonly-sections on[off]".
4246 This command is a hint that tells gdb that read-only sections
4247 really are read-only (ie. that their contents will not change).
4248 In this mode, gdb will go to the object file rather than the
4249 target to read memory from read-only sections (such as ".text").
4250 This can be a significant performance improvement on some
4251 (notably embedded) targets.
4253 * New command "generate-core-file" (or "gcore").
4255 This new gdb command allows the user to drop a core file of the child
4256 process state at any time. So far it's been implemented only for
4257 GNU/Linux and Solaris, but should be relatively easily ported to other
4258 hosts. Argument is core file name (defaults to core.<pid>).
4260 * New command line option
4262 GDB now accepts --pid or -p followed by a process id.
4264 * Change in command line behavior -- corefiles vs. process ids.
4266 There is a subtle behavior in the way in which GDB handles
4267 command line arguments. The first non-flag argument is always
4268 a program to debug, but the second non-flag argument may either
4269 be a corefile or a process id. Previously, GDB would attempt to
4270 open the second argument as a corefile, and if that failed, would
4271 issue a superfluous error message and then attempt to attach it as
4272 a process. Now, if the second argument begins with a non-digit,
4273 it will be treated as a corefile. If it begins with a digit,
4274 GDB will attempt to attach it as a process, and if no such process
4275 is found, will then attempt to open it as a corefile.
4277 * Changes in ARM configurations.
4279 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4280 configuration is fully multi-arch.
4282 * New native configurations
4284 ARM NetBSD arm*-*-netbsd*
4285 x86 OpenBSD i[3456]86-*-openbsd*
4286 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4287 Sparc64 running FreeBSD sparc64-*-freebsd*
4291 Sanyo XStormy16 xstormy16-elf
4293 * OBSOLETE configurations and files
4295 Configurations that have been declared obsolete in this release have
4296 been commented out. Unless there is activity to revive these
4297 configurations, the next release of GDB will have their sources
4298 permanently REMOVED.
4300 AMD 29k family via UDI a29k-amd-udi, udi29k
4301 A29K VxWorks a29k-*-vxworks
4302 AMD 29000 embedded, using EBMON a29k-none-none
4303 AMD 29000 embedded with COFF a29k-none-coff
4304 AMD 29000 embedded with a.out a29k-none-aout
4306 testsuite/gdb.hp/gdb.threads-hp/ directory
4308 * REMOVED configurations and files
4310 TI TMS320C80 tic80-*-*
4312 PowerPC Solaris powerpcle-*-solaris*
4313 PowerPC Windows NT powerpcle-*-cygwin32
4314 PowerPC Netware powerpc-*-netware*
4315 Harris/CXUX m88k m88*-harris-cxux*
4316 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4317 ns32k-utek-sysv* ns32k-utek-*
4318 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4319 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4320 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4321 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4322 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4324 * Changes to command line processing
4326 The new `--args' feature can be used to specify command-line arguments
4327 for the inferior from gdb's command line.
4329 * Changes to key bindings
4331 There is a new `operate-and-get-next' function bound to `C-o'.
4333 *** Changes in GDB 5.1.1
4335 Fix compile problem on DJGPP.
4337 Fix a problem with floating-point registers on the i386 being
4340 Fix to stop GDB crashing on .debug_str debug info.
4342 Numerous documentation fixes.
4344 Numerous testsuite fixes.
4346 *** Changes in GDB 5.1:
4348 * New native configurations
4350 Alpha FreeBSD alpha*-*-freebsd*
4351 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4352 MIPS GNU/Linux mips*-*-linux*
4353 MIPS SGI Irix 6.x mips*-sgi-irix6*
4354 ia64 AIX ia64-*-aix*
4355 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4359 Motorola 68HC11 and 68HC12 m68hc11-elf
4361 UltraSparc running GNU/Linux sparc64-*-linux*
4363 * OBSOLETE configurations and files
4365 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4366 Harris/CXUX m88k m88*-harris-cxux*
4367 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4368 ns32k-utek-sysv* ns32k-utek-*
4369 TI TMS320C80 tic80-*-*
4371 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4372 PowerPC Solaris powerpcle-*-solaris*
4373 PowerPC Windows NT powerpcle-*-cygwin32
4374 PowerPC Netware powerpc-*-netware*
4375 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4376 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4377 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4378 Apple Macintosh (MPW) host N/A
4380 stuff.c (Program to stuff files into a specially prepared space in kdb)
4381 kdb-start.c (Main loop for the standalone kernel debugger)
4383 Configurations that have been declared obsolete in this release have
4384 been commented out. Unless there is activity to revive these
4385 configurations, the next release of GDB will have their sources
4386 permanently REMOVED.
4388 * REMOVED configurations and files
4390 Altos 3068 m68*-altos-*
4391 Convex c1-*-*, c2-*-*
4393 ARM RISCix arm-*-* (as host)
4397 * GDB has been converted to ISO C.
4399 GDB's source code has been converted to ISO C. In particular, the
4400 sources are fully protoized, and rely on standard headers being
4405 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4407 * The MI enabled by default.
4409 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4410 revised and enabled by default. Packages which use GDB as a debugging
4411 engine behind a UI or another front end are encouraged to switch to
4412 using the GDB/MI interface, instead of the old annotations interface
4413 which is now deprecated.
4415 * Support for debugging Pascal programs.
4417 GDB now includes support for debugging Pascal programs. The following
4418 main features are supported:
4420 - Pascal-specific data types such as sets;
4422 - automatic recognition of Pascal sources based on file-name
4425 - Pascal-style display of data types, variables, and functions;
4427 - a Pascal expression parser.
4429 However, some important features are not yet supported.
4431 - Pascal string operations are not supported at all;
4433 - there are some problems with boolean types;
4435 - Pascal type hexadecimal constants are not supported
4436 because they conflict with the internal variables format;
4438 - support for Pascal objects and classes is not full yet;
4440 - unlike Pascal, GDB is case-sensitive for symbol names.
4442 * Changes in completion.
4444 Commands such as `shell', `run' and `set args', which pass arguments
4445 to inferior programs, now complete on file names, similar to what
4446 users expect at the shell prompt.
4448 Commands which accept locations, such as `disassemble', `print',
4449 `breakpoint', `until', etc. now complete on filenames as well as
4450 program symbols. Thus, if you type "break foob TAB", and the source
4451 files linked into the programs include `foobar.c', that file name will
4452 be one of the candidates for completion. However, file names are not
4453 considered for completion after you typed a colon that delimits a file
4454 name from a name of a function in that file, as in "break foo.c:bar".
4456 `set demangle-style' completes on available demangling styles.
4458 * New platform-independent commands:
4460 It is now possible to define a post-hook for a command as well as a
4461 hook that runs before the command. For more details, see the
4462 documentation of `hookpost' in the GDB manual.
4464 * Changes in GNU/Linux native debugging.
4466 Support for debugging multi-threaded programs has been completely
4467 revised for all platforms except m68k and sparc. You can now debug as
4468 many threads as your system allows you to have.
4470 Attach/detach is supported for multi-threaded programs.
4472 Support for SSE registers was added for x86. This doesn't work for
4473 multi-threaded programs though.
4475 * Changes in MIPS configurations.
4477 Multi-arch support is enabled for all MIPS configurations.
4479 GDB can now be built as native debugger on SGI Irix 6.x systems for
4480 debugging n32 executables. (Debugging 64-bit executables is not yet
4483 * Unified support for hardware watchpoints in all x86 configurations.
4485 Most (if not all) native x86 configurations support hardware-assisted
4486 breakpoints and watchpoints in a unified manner. This support
4487 implements debug register sharing between watchpoints, which allows to
4488 put a virtually infinite number of watchpoints on the same address,
4489 and also supports watching regions up to 16 bytes with several debug
4492 The new maintenance command `maintenance show-debug-regs' toggles
4493 debugging print-outs in functions that insert, remove, and test
4494 watchpoints and hardware breakpoints.
4496 * Changes in the DJGPP native configuration.
4498 New command ``info dos sysinfo'' displays assorted information about
4499 the CPU, OS, memory, and DPMI server.
4501 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4502 display information about segment descriptors stored in GDT, LDT, and
4505 New commands ``info dos pde'' and ``info dos pte'' display entries
4506 from Page Directory and Page Tables (for now works with CWSDPMI only).
4507 New command ``info dos address-pte'' displays the Page Table entry for
4508 a given linear address.
4510 GDB can now pass command lines longer than 126 characters to the
4511 program being debugged (requires an update to the libdbg.a library
4512 which is part of the DJGPP development kit).
4514 DWARF2 debug info is now supported.
4516 It is now possible to `step' and `next' through calls to `longjmp'.
4518 * Changes in documentation.
4520 All GDB documentation was converted to GFDL, the GNU Free
4521 Documentation License.
4523 Tracepoints-related commands are now fully documented in the GDB
4526 TUI, the Text-mode User Interface, is now documented in the manual.
4528 Tracepoints-related commands are now fully documented in the GDB
4531 The "GDB Internals" manual now has an index. It also includes
4532 documentation of `ui_out' functions, GDB coding standards, x86
4533 hardware watchpoints, and memory region attributes.
4535 * GDB's version number moved to ``version.in''
4537 The Makefile variable VERSION has been replaced by the file
4538 ``version.in''. People creating GDB distributions should update the
4539 contents of this file.
4543 GUD support is now a standard part of the EMACS distribution.
4545 *** Changes in GDB 5.0:
4547 * Improved support for debugging FP programs on x86 targets
4549 Unified and much-improved support for debugging floating-point
4550 programs on all x86 targets. In particular, ``info float'' now
4551 displays the FP registers in the same format on all x86 targets, with
4552 greater level of detail.
4554 * Improvements and bugfixes in hardware-assisted watchpoints
4556 It is now possible to watch array elements, struct members, and
4557 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4558 on x86 targets no longer erroneously trigger when the address is
4561 * Improvements in the native DJGPP version of GDB
4563 The distribution now includes all the scripts and auxiliary files
4564 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4565 machines ``out of the box''.
4567 The DJGPP version can now debug programs that use signals. It is
4568 possible to catch signals that happened in the debuggee, deliver
4569 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4570 would kill the program being debugged.) Programs that hook hardware
4571 interrupts (keyboard, timer, etc.) can also be debugged.
4573 It is now possible to debug DJGPP programs that redirect their
4574 standard handles or switch them to raw (as opposed to cooked) mode, or
4575 even close them. The command ``run < foo > bar'' works as expected,
4576 and ``info terminal'' reports useful information about the debuggee's
4577 terminal, including raw/cooked mode, redirection, etc.
4579 The DJGPP version now uses termios functions for console I/O, which
4580 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4583 DOS-style file names with drive letters are now fully supported by
4586 It is now possible to debug DJGPP programs that switch their working
4587 directory. It is also possible to rerun the debuggee any number of
4588 times without restarting GDB; thus, you can use the same setup,
4589 breakpoints, etc. for many debugging sessions.
4591 * New native configurations
4593 ARM GNU/Linux arm*-*-linux*
4594 PowerPC GNU/Linux powerpc-*-linux*
4598 Motorola MCore mcore-*-*
4599 x86 VxWorks i[3456]86-*-vxworks*
4600 PowerPC VxWorks powerpc-*-vxworks*
4601 TI TMS320C80 tic80-*-*
4603 * OBSOLETE configurations
4605 Altos 3068 m68*-altos-*
4606 Convex c1-*-*, c2-*-*
4608 ARM RISCix arm-*-* (as host)
4611 Configurations that have been declared obsolete will be commented out,
4612 but the code will be left in place. If there is no activity to revive
4613 these configurations before the next release of GDB, the sources will
4614 be permanently REMOVED.
4616 * Gould support removed
4618 Support for the Gould PowerNode and NP1 has been removed.
4620 * New features for SVR4
4622 On SVR4 native platforms (such as Solaris), if you attach to a process
4623 without first loading a symbol file, GDB will now attempt to locate and
4624 load symbols from the running process's executable file.
4626 * Many C++ enhancements
4628 C++ support has been greatly improved. Overload resolution now works properly
4629 in almost all cases. RTTI support is on the way.
4631 * Remote targets can connect to a sub-program
4633 A popen(3) style serial-device has been added. This device starts a
4634 sub-process (such as a stand-alone simulator) and then communicates
4635 with that. The sub-program to run is specified using the syntax
4636 ``|<program> <args>'' vis:
4638 (gdb) set remotedebug 1
4639 (gdb) target extended-remote |mn10300-elf-sim program-args
4641 * MIPS 64 remote protocol
4643 A long standing bug in the mips64 remote protocol where by GDB
4644 expected certain 32 bit registers (ex SR) to be transfered as 32
4645 instead of 64 bits has been fixed.
4647 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4648 added to provide backward compatibility with older versions of GDB.
4650 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4652 The command ``set remotebinarydownload'' command has been replaced by
4653 ``set remote X-packet''. Other commands in ``set remote'' family
4654 include ``set remote P-packet''.
4656 * Breakpoint commands accept ranges.
4658 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4659 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4660 ``tracepoint passcount'' also accepts a range of tracepoints.
4662 * ``apropos'' command added.
4664 The ``apropos'' command searches through command names and
4665 documentation strings, printing out matches, making it much easier to
4666 try to find a command that does what you are looking for.
4670 A new machine oriented interface (MI) has been added to GDB. This
4671 interface is designed for debug environments running GDB as a separate
4672 process. This is part of the long term libGDB project. See the
4673 "GDB/MI" chapter of the GDB manual for further information. It can be
4674 enabled by configuring with:
4676 .../configure --enable-gdbmi
4678 *** Changes in GDB-4.18:
4680 * New native configurations
4682 HP-UX 10.20 hppa*-*-hpux10.20
4683 HP-UX 11.x hppa*-*-hpux11.0*
4684 M68K GNU/Linux m68*-*-linux*
4688 Fujitsu FR30 fr30-*-elf*
4689 Intel StrongARM strongarm-*-*
4690 Mitsubishi D30V d30v-*-*
4692 * OBSOLETE configurations
4694 Gould PowerNode, NP1 np1-*-*, pn-*-*
4696 Configurations that have been declared obsolete will be commented out,
4697 but the code will be left in place. If there is no activity to revive
4698 these configurations before the next release of GDB, the sources will
4699 be permanently REMOVED.
4703 As a compatibility experiment, GDB's source files buildsym.h and
4704 buildsym.c have been converted to pure standard C, no longer
4705 containing any K&R compatibility code. We believe that all systems in
4706 use today either come with a standard C compiler, or have a GCC port
4707 available. If this is not true, please report the affected
4708 configuration to bug-gdb@gnu.org immediately. See the README file for
4709 information about getting a standard C compiler if you don't have one
4714 GDB now uses readline 2.2.
4716 * set extension-language
4718 You can now control the mapping between filename extensions and source
4719 languages by using the `set extension-language' command. For instance,
4720 you can ask GDB to treat .c files as C++ by saying
4721 set extension-language .c c++
4722 The command `info extensions' lists all of the recognized extensions
4723 and their associated languages.
4725 * Setting processor type for PowerPC and RS/6000
4727 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4728 you can use the `set processor' command to specify what variant of the
4729 PowerPC family you are debugging. The command
4733 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4734 following PowerPC and RS6000 variants:
4736 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4737 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4739 403GC IBM PowerPC 403GC
4740 505 Motorola PowerPC 505
4741 860 Motorola PowerPC 860 or 850
4742 601 Motorola PowerPC 601
4743 602 Motorola PowerPC 602
4744 603 Motorola/IBM PowerPC 603 or 603e
4745 604 Motorola PowerPC 604 or 604e
4746 750 Motorola/IBM PowerPC 750 or 750
4748 At the moment, this command just tells GDB what to name the
4749 special-purpose processor registers. Since almost all the affected
4750 registers are inaccessible to user-level programs, this command is
4751 only useful for remote debugging in its present form.
4755 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4756 more extensive support for HP-UX. Added features include shared
4757 library support, kernel threads and hardware watchpoints for 11.00,
4758 support for HP's ANSI C and C++ compilers, and a compatibility mode
4759 for xdb and dbx commands.
4763 HP's donation includes the new concept of catchpoints, which is a
4764 generalization of the old catch command. On HP-UX, it is now possible
4765 to catch exec, fork, and vfork, as well as library loading.
4767 This means that the existing catch command has changed; its first
4768 argument now specifies the type of catch to be set up. See the
4769 output of "help catch" for a list of catchpoint types.
4771 * Debugging across forks
4773 On HP-UX, you can choose which process to debug when a fork() happens
4778 HP has donated a curses-based terminal user interface (TUI). To get
4779 it, build with --enable-tui. Although this can be enabled for any
4780 configuration, at present it only works for native HP debugging.
4782 * GDB remote protocol additions
4784 A new protocol packet 'X' that writes binary data is now available.
4785 Default behavior is to try 'X', then drop back to 'M' if the stub
4786 fails to respond. The settable variable `remotebinarydownload'
4787 allows explicit control over the use of 'X'.
4789 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4790 full 64-bit address. The command
4792 set remoteaddresssize 32
4794 can be used to revert to the old behaviour. For existing remote stubs
4795 the change should not be noticed, as the additional address information
4798 In order to assist in debugging stubs, you may use the maintenance
4799 command `packet' to send any text string to the stub. For instance,
4801 maint packet heythere
4803 sends the packet "$heythere#<checksum>". Note that it is very easy to
4804 disrupt a debugging session by sending the wrong packet at the wrong
4807 The compare-sections command allows you to compare section data on the
4808 target to what is in the executable file without uploading or
4809 downloading, by comparing CRC checksums.
4811 * Tracing can collect general expressions
4813 You may now collect general expressions at tracepoints. This requires
4814 further additions to the target-side stub; see tracepoint.c and
4815 doc/agentexpr.texi for further details.
4817 * mask-address variable for Mips
4819 For Mips targets, you may control the zeroing of the upper 32 bits of
4820 a 64-bit address by entering `set mask-address on'. This is mainly
4821 of interest to users of embedded R4xxx and R5xxx processors.
4823 * Higher serial baud rates
4825 GDB's serial code now allows you to specify baud rates 57600, 115200,
4826 230400, and 460800 baud. (Note that your host system may not be able
4827 to achieve all of these rates.)
4831 The i960 configuration now includes an initial implementation of a
4832 builtin simulator, contributed by Jim Wilson.
4835 *** Changes in GDB-4.17:
4837 * New native configurations
4839 Alpha GNU/Linux alpha*-*-linux*
4840 Unixware 2.x i[3456]86-unixware2*
4841 Irix 6.x mips*-sgi-irix6*
4842 PowerPC GNU/Linux powerpc-*-linux*
4843 PowerPC Solaris powerpcle-*-solaris*
4844 Sparc GNU/Linux sparc-*-linux*
4845 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4849 Argonaut Risc Chip (ARC) arc-*-*
4850 Hitachi H8/300S h8300*-*-*
4851 Matsushita MN10200 w/simulator mn10200-*-*
4852 Matsushita MN10300 w/simulator mn10300-*-*
4853 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4854 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4855 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4856 Mitsubishi D10V w/simulator d10v-*-*
4857 Mitsubishi M32R/D w/simulator m32r-*-elf*
4858 Tsqware Sparclet sparclet-*-*
4859 NEC V850 w/simulator v850-*-*
4861 * New debugging protocols
4863 ARM with RDI protocol arm*-*-*
4864 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4865 DDB and LSI variants of PMON protocol mips*-*-*
4866 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4867 PowerPC with SDS protocol powerpc{,le}-*-eabi
4868 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4872 All configurations can now understand and use the DWARF 2 debugging
4873 format. The choice is automatic, if the symbol file contains DWARF 2
4878 GDB now includes basic Java language support. This support is
4879 only useful with Java compilers that produce native machine code.
4881 * solib-absolute-prefix and solib-search-path
4883 For SunOS and SVR4 shared libraries, you may now set the prefix for
4884 loading absolute shared library symbol files, and the search path for
4885 locating non-absolute shared library symbol files.
4887 * Live range splitting
4889 GDB can now effectively debug code for which GCC has performed live
4890 range splitting as part of its optimization. See gdb/doc/LRS for
4891 more details on the expected format of the stabs information.
4895 GDB's support for the GNU Hurd, including thread debugging, has been
4896 updated to work with current versions of the Hurd.
4900 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4901 instruction set. ARM GDB automatically detects when Thumb
4902 instructions are in use, and adjusts disassembly and backtracing
4907 GDB's MIPS target configurations now handle the MIP16 16-bit
4912 GDB now includes support for overlays; if an executable has been
4913 linked such that multiple sections are based at the same address, GDB
4914 will decide which section to use for symbolic info. You can choose to
4915 control the decision manually, using overlay commands, or implement
4916 additional target-side support and use "overlay load-target" to bring
4917 in the overlay mapping. Do "help overlay" for more detail.
4921 The command "info symbol <address>" displays information about
4922 the symbol at the specified address.
4926 The standard remote protocol now includes an extension that allows
4927 asynchronous collection and display of trace data. This requires
4928 extensive support in the target-side debugging stub. Tracing mode
4929 includes a new interaction mode in GDB and new commands: see the
4930 file tracepoint.c for more details.
4934 Configurations for embedded MIPS now include a simulator contributed
4935 by Cygnus Solutions. The simulator supports the instruction sets
4936 of most MIPS variants.
4940 Sparc configurations may now include the ERC32 simulator contributed
4941 by the European Space Agency. The simulator is not built into
4942 Sparc targets by default; configure with --enable-sim to include it.
4946 For target configurations that may include multiple variants of a
4947 basic architecture (such as MIPS and SH), you may now set the
4948 architecture explicitly. "set arch" sets, "info arch" lists
4949 the possible architectures.
4951 *** Changes in GDB-4.16:
4953 * New native configurations
4955 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4956 M68K NetBSD m68k-*-netbsd*
4957 PowerPC AIX 4.x powerpc-*-aix*
4958 PowerPC MacOS powerpc-*-macos*
4959 PowerPC Windows NT powerpcle-*-cygwin32
4960 RS/6000 AIX 4.x rs6000-*-aix4*
4964 ARM with RDP protocol arm-*-*
4965 I960 with MON960 i960-*-coff
4966 MIPS VxWorks mips*-*-vxworks*
4967 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4968 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4970 Matra Sparclet sparclet-*-*
4974 The powerpc-eabi configuration now includes the PSIM simulator,
4975 contributed by Andrew Cagney, with assistance from Mike Meissner.
4976 PSIM is a very elaborate model of the PowerPC, including not only
4977 basic instruction set execution, but also details of execution unit
4978 performance and I/O hardware. See sim/ppc/README for more details.
4982 GDB now works with Solaris 2.5.
4984 * Windows 95/NT native
4986 GDB will now work as a native debugger on Windows 95 and Windows NT.
4987 To build it from source, you must use the "gnu-win32" environment,
4988 which uses a DLL to emulate enough of Unix to run the GNU tools.
4989 Further information, binaries, and sources are available at
4990 ftp.cygnus.com, under pub/gnu-win32.
4992 * dont-repeat command
4994 If a user-defined command includes the command `dont-repeat', then the
4995 command will not be repeated if the user just types return. This is
4996 useful if the command is time-consuming to run, so that accidental
4997 extra keystrokes don't run the same command many times.
4999 * Send break instead of ^C
5001 The standard remote protocol now includes an option to send a break
5002 rather than a ^C to the target in order to interrupt it. By default,
5003 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5005 * Remote protocol timeout
5007 The standard remote protocol includes a new variable `remotetimeout'
5008 that allows you to set the number of seconds before GDB gives up trying
5009 to read from the target. The default value is 2.
5011 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5013 By default GDB will automatically keep track of objects as they are
5014 loaded and unloaded by the dynamic linker. By using the command `set
5015 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5016 when shared library events occur, thus allowing you to set breakpoints
5017 in shared libraries which are explicitly loaded by the inferior.
5019 Note this feature does not work on hpux8. On hpux9 you must link
5020 /usr/lib/end.o into your program. This feature should work
5021 automatically on hpux10.
5023 * Irix 5.x hardware watchpoint support
5025 Irix 5 configurations now support the use of hardware watchpoints.
5027 * Mips protocol "SYN garbage limit"
5029 When debugging a Mips target using the `target mips' protocol, you
5030 may set the number of characters that GDB will ignore by setting
5031 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5032 every character. The default value is 1050.
5034 * Recording and replaying remote debug sessions
5036 If you set `remotelogfile' to the name of a file, gdb will write to it
5037 a recording of a remote debug session. This recording may then be
5038 replayed back to gdb using "gdbreplay". See gdbserver/README for
5039 details. This is useful when you have a problem with GDB while doing
5040 remote debugging; you can make a recording of the session and send it
5041 to someone else, who can then recreate the problem.
5043 * Speedups for remote debugging
5045 GDB includes speedups for downloading and stepping MIPS systems using
5046 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5047 and more efficient S-record downloading.
5049 * Memory use reductions and statistics collection
5051 GDB now uses less memory and reports statistics about memory usage.
5052 Try the `maint print statistics' command, for example.
5054 *** Changes in GDB-4.15:
5056 * Psymtabs for XCOFF
5058 The symbol reader for AIX GDB now uses partial symbol tables. This
5059 can greatly improve startup time, especially for large executables.
5061 * Remote targets use caching
5063 Remote targets now use a data cache to speed up communication with the
5064 remote side. The data cache could lead to incorrect results because
5065 it doesn't know about volatile variables, thus making it impossible to
5066 debug targets which use memory mapped I/O devices. `set remotecache
5067 off' turns the the data cache off.
5069 * Remote targets may have threads
5071 The standard remote protocol now includes support for multiple threads
5072 in the target system, using new protocol commands 'H' and 'T'. See
5073 gdb/remote.c for details.
5077 If GDB is configured with `--enable-netrom', then it will include
5078 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5079 acts as though it is a bank of ROM on the target board, but you can
5080 write into it over the network. GDB's support consists only of
5081 support for fast loading into the emulated ROM; to debug, you must use
5082 another protocol, such as standard remote protocol. The usual
5083 sequence is something like
5085 target nrom <netrom-hostname>
5087 target remote <netrom-hostname>:1235
5091 GDB now includes support for the Apple Macintosh, as a host only. It
5092 may be run as either an MPW tool or as a standalone application, and
5093 it can debug through the serial port. All the usual GDB commands are
5094 available, but to the target command, you must supply "serial" as the
5095 device type instead of "/dev/ttyXX". See mpw-README in the main
5096 directory for more information on how to build. The MPW configuration
5097 scripts */mpw-config.in support only a few targets, and only the
5098 mips-idt-ecoff target has been tested.
5102 GDB configuration now uses autoconf. This is not user-visible,
5103 but does simplify configuration and building.
5107 GDB now supports hpux10.
5109 *** Changes in GDB-4.14:
5111 * New native configurations
5113 x86 FreeBSD i[345]86-*-freebsd
5114 x86 NetBSD i[345]86-*-netbsd
5115 NS32k NetBSD ns32k-*-netbsd
5116 Sparc NetBSD sparc-*-netbsd
5120 A29K VxWorks a29k-*-vxworks
5121 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5122 CPU32 EST-300 emulator m68*-*-est*
5123 PowerPC ELF powerpc-*-elf
5126 * Alpha OSF/1 support for procfs
5128 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5129 possible to attach to running processes. As the mounting of the /proc
5130 filesystem is optional on the Alpha, GDB automatically determines
5131 the availability of /proc during startup. This can lead to problems
5132 if /proc is unmounted after GDB has been started.
5134 * Arguments to user-defined commands
5136 User commands may accept up to 10 arguments separated by whitespace.
5137 Arguments are accessed within the user command via $arg0..$arg9. A
5140 print $arg0 + $arg1 + $arg2
5142 To execute the command use:
5145 Defines the command "adder" which prints the sum of its three arguments.
5146 Note the arguments are text substitutions, so they may reference variables,
5147 use complex expressions, or even perform inferior function calls.
5149 * New `if' and `while' commands
5151 This makes it possible to write more sophisticated user-defined
5152 commands. Both commands take a single argument, which is the
5153 expression to evaluate, and must be followed by the commands to
5154 execute, one per line, if the expression is nonzero, the list being
5155 terminated by the word `end'. The `if' command list may include an
5156 `else' word, which causes the following commands to be executed only
5157 if the expression is zero.
5159 * Fortran source language mode
5161 GDB now includes partial support for Fortran 77. It will recognize
5162 Fortran programs and can evaluate a subset of Fortran expressions, but
5163 variables and functions may not be handled correctly. GDB will work
5164 with G77, but does not yet know much about symbols emitted by other
5167 * Better HPUX support
5169 Most debugging facilities now work on dynamic executables for HPPAs
5170 running hpux9 or later. You can attach to running dynamically linked
5171 processes, but by default the dynamic libraries will be read-only, so
5172 for instance you won't be able to put breakpoints in them. To change
5173 that behavior do the following before running the program:
5179 This will cause the libraries to be mapped private and read-write.
5180 To revert to the normal behavior, do this:
5186 You cannot set breakpoints or examine data in the library until after
5187 the library is loaded if the function/data symbols do not have
5190 GDB can now also read debug symbols produced by the HP C compiler on
5191 HPPAs (sorry, no C++, Fortran or 68k support).
5193 * Target byte order now dynamically selectable
5195 You can choose which byte order to use with a target system, via the
5196 commands "set endian big" and "set endian little", and you can see the
5197 current setting by using "show endian". You can also give the command
5198 "set endian auto", in which case GDB will use the byte order
5199 associated with the executable. Currently, only embedded MIPS
5200 configurations support dynamic selection of target byte order.
5202 * New DOS host serial code
5204 This version uses DPMI interrupts to handle buffered I/O, so you
5205 no longer need to run asynctsr when debugging boards connected to
5208 *** Changes in GDB-4.13:
5210 * New "complete" command
5212 This lists all the possible completions for the rest of the line, if it
5213 were to be given as a command itself. This is intended for use by emacs.
5215 * Trailing space optional in prompt
5217 "set prompt" no longer adds a space for you after the prompt you set. This
5218 allows you to set a prompt which ends in a space or one that does not.
5220 * Breakpoint hit counts
5222 "info break" now displays a count of the number of times the breakpoint
5223 has been hit. This is especially useful in conjunction with "ignore"; you
5224 can ignore a large number of breakpoint hits, look at the breakpoint info
5225 to see how many times the breakpoint was hit, then run again, ignoring one
5226 less than that number, and this will get you quickly to the last hit of
5229 * Ability to stop printing at NULL character
5231 "set print null-stop" will cause GDB to stop printing the characters of
5232 an array when the first NULL is encountered. This is useful when large
5233 arrays actually contain only short strings.
5235 * Shared library breakpoints
5237 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5238 breakpoints in shared libraries before the executable is run.
5240 * Hardware watchpoints
5242 There is a new hardware breakpoint for the watch command for sparclite
5243 targets. See gdb/sparclite/hw_breakpoint.note.
5245 Hardware watchpoints are also now supported under GNU/Linux.
5249 Annotations have been added. These are for use with graphical interfaces,
5250 and are still experimental. Currently only gdba.el uses these.
5252 * Improved Irix 5 support
5254 GDB now works properly with Irix 5.2.
5256 * Improved HPPA support
5258 GDB now works properly with the latest GCC and GAS.
5260 * New native configurations
5262 Sequent PTX4 i[34]86-sequent-ptx4
5263 HPPA running OSF/1 hppa*-*-osf*
5264 Atari TT running SVR4 m68*-*-sysv4*
5265 RS/6000 LynxOS rs6000-*-lynxos*
5269 OS/9000 i[34]86-*-os9k
5270 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5273 * Hitachi SH7000 and E7000-PC ICE support
5275 There is now support for communicating with the Hitachi E7000-PC ICE.
5276 This is available automatically when GDB is configured for the SH.
5280 As usual, a variety of small fixes and improvements, both generic
5281 and configuration-specific. See the ChangeLog for more detail.
5283 *** Changes in GDB-4.12:
5285 * Irix 5 is now supported
5289 GDB-4.12 on the HPPA has a number of changes which make it unable
5290 to debug the output from the currently released versions of GCC and
5291 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5292 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5293 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5296 *** Changes in GDB-4.11:
5298 * User visible changes:
5302 The "set remotedebug" option is now consistent between the mips remote
5303 target, remote targets using the gdb-specific protocol, UDI (AMD's
5304 debug protocol for the 29k) and the 88k bug monitor. It is now an
5305 integer specifying a debug level (normally 0 or 1, but 2 means more
5306 debugging info for the mips target).
5308 * DEC Alpha native support
5310 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5311 debug info, but GDB works fairly well with the DEC compiler and should
5312 work with a future GCC release. See the README file for a few
5313 Alpha-specific notes.
5315 * Preliminary thread implementation
5317 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5319 * LynxOS native and target support for 386
5321 This release has been hosted on LynxOS 2.2, and also can be configured
5322 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5325 * Improvements in C++ mangling/demangling.
5327 This release has much better g++ debugging, specifically in name
5328 mangling/demangling, virtual function calls, print virtual table,
5329 call methods, ...etc.
5331 *** Changes in GDB-4.10:
5333 * User visible changes:
5335 Remote debugging using the GDB-specific (`target remote') protocol now
5336 supports the `load' command. This is only useful if you have some
5337 other way of getting the stub to the target system, and you can put it
5338 somewhere in memory where it won't get clobbered by the download.
5340 Filename completion now works.
5342 When run under emacs mode, the "info line" command now causes the
5343 arrow to point to the line specified. Also, "info line" prints
5344 addresses in symbolic form (as well as hex).
5346 All vxworks based targets now support a user settable option, called
5347 vxworks-timeout. This option represents the number of seconds gdb
5348 should wait for responses to rpc's. You might want to use this if
5349 your vxworks target is, perhaps, a slow software simulator or happens
5350 to be on the far side of a thin network line.
5354 This release contains support for using a DEC alpha as a GDB host for
5355 cross debugging. Native alpha debugging is not supported yet.
5358 *** Changes in GDB-4.9:
5362 This is the first GDB release which is accompanied by a matching testsuite.
5363 The testsuite requires installation of dejagnu, which should be available
5364 via ftp from most sites that carry GNU software.
5368 'Cfront' style demangling has had its name changed to 'ARM' style, to
5369 emphasize that it was written from the specifications in the C++ Annotated
5370 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5371 disclaimers, it still generated too much confusion with users attempting to
5372 use gdb with AT&T cfront.
5376 GDB now uses a standard remote interface to a simulator library.
5377 So far, the library contains simulators for the Zilog Z8001/2, the
5378 Hitachi H8/300, H8/500 and Super-H.
5380 * New targets supported
5382 H8/300 simulator h8300-hitachi-hms or h8300hms
5383 H8/500 simulator h8500-hitachi-hms or h8500hms
5384 SH simulator sh-hitachi-hms or sh
5385 Z8000 simulator z8k-zilog-none or z8ksim
5386 IDT MIPS board over serial line mips-idt-ecoff
5388 Cross-debugging to GO32 targets is supported. It requires a custom
5389 version of the i386-stub.c module which is integrated with the
5390 GO32 memory extender.
5392 * New remote protocols
5394 MIPS remote debugging protocol.
5396 * New source languages supported
5398 This version includes preliminary support for Chill, a Pascal like language
5399 used by telecommunications companies. Chill support is also being integrated
5400 into the GNU compiler, but we don't know when it will be publically available.
5403 *** Changes in GDB-4.8:
5405 * HP Precision Architecture supported
5407 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5408 version of this support was available as a set of patches from the
5409 University of Utah. GDB does not support debugging of programs
5410 compiled with the HP compiler, because HP will not document their file
5411 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5412 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5414 Many problems in the preliminary version have been fixed.
5416 * Faster and better demangling
5418 We have improved template demangling and fixed numerous bugs in the GNU style
5419 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5420 character types (wchar_t) are now supported. Demangling of each symbol is now
5421 only done once, and is cached when the symbol table for a file is read in.
5422 This results in a small increase in memory usage for C programs, a moderate
5423 increase in memory usage for C++ programs, and a fantastic speedup in
5426 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5427 from the specifications in the Annotated Reference Manual, which AT&T's
5428 compiler does not actually implement.
5430 * G++ multiple inheritance compiler problem
5432 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5433 inheritance lattices was reworked to properly discover ambiguities. We
5434 recently found an example which causes this new algorithm to fail in a
5435 very subtle way, producing bad debug information for those classes.
5436 The file 'gcc.patch' (in this directory) can be applied to gcc to
5437 circumvent the problem. A future GCC release will contain a complete
5440 The previous G++ debug info problem (mentioned below for the gdb-4.7
5441 release) is fixed in gcc version 2.3.2.
5443 * Improved configure script
5445 The `configure' script will now attempt to guess your system type if
5446 you don't supply a host system type. The old scheme of supplying a
5447 host system triplet is preferable over using this. All the magic is
5448 done in the new `config.guess' script. Examine it for details.
5450 We have also brought our configure script much more in line with the FSF's
5451 version. It now supports the --with-xxx options. In particular,
5452 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5453 The resulting GDB will not be able to read arbitrary object file formats --
5454 only the format ``expected'' to be used on the configured target system.
5455 We hope to make this the default in a future release.
5457 * Documentation improvements
5459 There's new internal documentation on how to modify GDB, and how to
5460 produce clean changes to the code. We implore people to read it
5461 before submitting changes.
5463 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5464 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5465 `info' files are also provided. To build `info' files from scratch,
5466 you will need the latest `makeinfo' release, which will be available in
5467 a future texinfo-X.Y release.
5469 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5470 We're not sure exactly which versions have this problem, but it has
5471 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5472 or better. If that isn't possible, there is a patch in
5473 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5474 around this problem.
5478 GDB now supports array constants that can be used in expressions typed in by
5479 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5480 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5483 The new directory `gdb/sparclite' contains a program that demonstrates
5484 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5486 * New native hosts supported
5488 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5489 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5491 * New targets supported
5493 AMD 29k family via UDI a29k-amd-udi or udi29k
5495 * New file formats supported
5497 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5498 HPUX core files, and SCO 3.2v2 core files.
5502 Attaching to processes now works again; thanks for the many bug reports.
5504 We have also stomped on a bunch of core dumps caused by
5505 printf_filtered("%s") problems.
5507 We eliminated a copyright problem on the rpc and ptrace header files
5508 for VxWorks, which was discovered at the last minute during the 4.7
5509 release. You should now be able to build a VxWorks GDB.
5511 You can now interrupt gdb while an attached process is running. This
5512 will cause the attached process to stop, and give control back to GDB.
5514 We fixed problems caused by using too many file descriptors
5515 for reading symbols from object files and libraries. This was
5516 especially a problem for programs that used many (~100) shared
5519 The `step' command now only enters a subroutine if there is line number
5520 information for the subroutine. Otherwise it acts like the `next'
5521 command. Previously, `step' would enter subroutines if there was
5522 any debugging information about the routine. This avoids problems
5523 when using `cc -g1' on MIPS machines.
5525 * Internal improvements
5527 GDB's internal interfaces have been improved to make it easier to support
5528 debugging of multiple languages in the future.
5530 GDB now uses a common structure for symbol information internally.
5531 Minimal symbols (derived from linkage symbols in object files), partial
5532 symbols (from a quick scan of debug information), and full symbols
5533 contain a common subset of information, making it easier to write
5534 shared code that handles any of them.
5536 * New command line options
5538 We now accept --silent as an alias for --quiet.
5542 The memory-mapped-malloc library is now licensed under the GNU Library
5543 General Public License.
5545 *** Changes in GDB-4.7:
5547 * Host/native/target split
5549 GDB has had some major internal surgery to untangle the support for
5550 hosts and remote targets. Now, when you configure GDB for a remote
5551 target, it will no longer load in all of the support for debugging
5552 local programs on the host. When fully completed and tested, this will
5553 ensure that arbitrary host/target combinations are possible.
5555 The primary conceptual shift is to separate the non-portable code in
5556 GDB into three categories. Host specific code is required any time GDB
5557 is compiled on that host, regardless of the target. Target specific
5558 code relates to the peculiarities of the target, but can be compiled on
5559 any host. Native specific code is everything else: it can only be
5560 built when the host and target are the same system. Child process
5561 handling and core file support are two common `native' examples.
5563 GDB's use of /proc for controlling Unix child processes is now cleaner.
5564 It has been split out into a single module under the `target_ops' vector,
5565 plus two native-dependent functions for each system that uses /proc.
5567 * New hosts supported
5569 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5570 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5571 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5573 * New targets supported
5575 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5576 68030 and CPU32 m68030-*-*, m68332-*-*
5578 * New native hosts supported
5580 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5581 (386bsd is not well tested yet)
5582 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5584 * New file formats supported
5586 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5587 supports reading of `a.out.adobe' object files, which are an a.out
5588 format extended with minimal information about multiple sections.
5592 `show copying' is the same as the old `info copying'.
5593 `show warranty' is the same as `info warrantee'.
5594 These were renamed for consistency. The old commands continue to work.
5596 `info handle' is a new alias for `info signals'.
5598 You can now define pre-command hooks, which attach arbitrary command
5599 scripts to any command. The commands in the hook will be executed
5600 prior to the user's command. You can also create a hook which will be
5601 executed whenever the program stops. See gdb.texinfo.
5605 We now deal with Cfront style name mangling, and can even extract type
5606 info from mangled symbols. GDB can automatically figure out which
5607 symbol mangling style your C++ compiler uses.
5609 Calling of methods and virtual functions has been improved as well.
5613 The crash that occured when debugging Sun Ansi-C compiled binaries is
5614 fixed. This was due to mishandling of the extra N_SO stabs output
5617 We also finally got Ultrix 4.2 running in house, and fixed core file
5618 support, with help from a dozen people on the net.
5620 John M. Farrell discovered that the reason that single-stepping was so
5621 slow on all of the Mips based platforms (primarily SGI and DEC) was
5622 that we were trying to demangle and lookup a symbol used for internal
5623 purposes on every instruction that was being stepped through. Changing
5624 the name of that symbol so that it couldn't be mistaken for a C++
5625 mangled symbol sped things up a great deal.
5627 Rich Pixley sped up symbol lookups in general by getting much smarter
5628 about when C++ symbol mangling is necessary. This should make symbol
5629 completion (TAB on the command line) much faster. It's not as fast as
5630 we'd like, but it's significantly faster than gdb-4.6.
5634 A new user controllable variable 'call_scratch_address' can
5635 specify the location of a scratch area to be used when GDB
5636 calls a function in the target. This is necessary because the
5637 usual method of putting the scratch area on the stack does not work
5638 in systems that have separate instruction and data spaces.
5640 We integrated changes to support the 29k UDI (Universal Debugger
5641 Interface), but discovered at the last minute that we didn't have all
5642 of the appropriate copyright paperwork. We are working with AMD to
5643 resolve this, and hope to have it available soon.
5647 We have sped up the remote serial line protocol, especially for targets
5648 with lots of registers. It now supports a new `expedited status' ('T')
5649 message which can be used in place of the existing 'S' status message.
5650 This allows the remote stub to send only the registers that GDB
5651 needs to make a quick decision about single-stepping or conditional
5652 breakpoints, eliminating the need to fetch the entire register set for
5653 each instruction being stepped through.
5655 The GDB remote serial protocol now implements a write-through cache for
5656 registers, only re-reading the registers if the target has run.
5658 There is also a new remote serial stub for SPARC processors. You can
5659 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5660 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5661 processor with a serial port.
5665 Configure.in files have become much easier to read and modify. A new
5666 `table driven' format makes it more obvious what configurations are
5667 supported, and what files each one uses.
5671 There is a new opcodes library which will eventually contain all of the
5672 disassembly routines and opcode tables. At present, it only contains
5673 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5674 disassembler (binutils/objdump) to share these routines.
5676 The libiberty library is now copylefted under the GNU Library General
5677 Public License. This allows more liberal use, and was done so libg++
5678 can use it. This makes no difference to GDB, since the Library License
5679 grants all the rights from the General Public License.
5683 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5684 reference to the stabs symbol info used by the debugger. It is (as far
5685 as we know) the only published document on this fascinating topic. We
5686 encourage you to read it, compare it to the stabs information on your
5687 system, and send improvements on the document in general (to
5688 bug-gdb@prep.ai.mit.edu).
5690 And, of course, many bugs have been fixed.
5693 *** Changes in GDB-4.6:
5695 * Better support for C++ function names
5697 GDB now accepts as input the "demangled form" of C++ overloaded function
5698 names and member function names, and can do command completion on such names
5699 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5700 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5701 Make use of command completion, it is your friend.
5703 GDB also now accepts a variety of C++ mangled symbol formats. They are
5704 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5705 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5706 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5707 for the list of formats.
5709 * G++ symbol mangling problem
5711 Recent versions of gcc have a bug in how they emit debugging information for
5712 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5713 directory) can be applied to gcc to fix the problem. Alternatively, if you
5714 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5715 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5716 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5719 * New 'maintenance' command
5721 All of the commands related to hacking GDB internals have been moved out of
5722 the main command set, and now live behind the 'maintenance' command. This
5723 can also be abbreviated as 'mt'. The following changes were made:
5725 dump-me -> maintenance dump-me
5726 info all-breakpoints -> maintenance info breakpoints
5727 printmsyms -> maintenance print msyms
5728 printobjfiles -> maintenance print objfiles
5729 printpsyms -> maintenance print psymbols
5730 printsyms -> maintenance print symbols
5732 The following commands are new:
5734 maintenance demangle Call internal GDB demangler routine to
5735 demangle a C++ link name and prints the result.
5736 maintenance print type Print a type chain for a given symbol
5738 * Change to .gdbinit file processing
5740 We now read the $HOME/.gdbinit file before processing the argv arguments
5741 (e.g. reading symbol files or core files). This allows global parameters to
5742 be set, which will apply during the symbol reading. The ./.gdbinit is still
5743 read after argv processing.
5745 * New hosts supported
5747 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5749 GNU/Linux support i386-unknown-linux or linux
5751 We are also including code to support the HP/PA running BSD and HPUX. This
5752 is almost guaranteed not to work, as we didn't have time to test or build it
5753 for this release. We are including it so that the more adventurous (or
5754 masochistic) of you can play with it. We also had major problems with the
5755 fact that the compiler that we got from HP doesn't support the -g option.
5758 * New targets supported
5760 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5762 * More smarts about finding #include files
5764 GDB now remembers the compilation directory for all include files, and for
5765 all files from which C is generated (like yacc and lex sources). This
5766 greatly improves GDB's ability to find yacc/lex sources, and include files,
5767 especially if you are debugging your program from a directory different from
5768 the one that contains your sources.
5770 We also fixed a bug which caused difficulty with listing and setting
5771 breakpoints in include files which contain C code. (In the past, you had to
5772 try twice in order to list an include file that you hadn't looked at before.)
5774 * Interesting infernals change
5776 GDB now deals with arbitrary numbers of sections, where the symbols for each
5777 section must be relocated relative to that section's landing place in the
5778 target's address space. This work was needed to support ELF with embedded
5779 stabs used by Solaris-2.0.
5781 * Bug fixes (of course!)
5783 There have been loads of fixes for the following things:
5784 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5785 i960, stabs, DOS(GO32), procfs, etc...
5787 See the ChangeLog for details.
5789 *** Changes in GDB-4.5:
5791 * New machines supported (host and target)
5793 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5795 SGI Irix-4.x mips-sgi-irix4 or iris4
5797 * New malloc package
5799 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5800 Mmalloc is capable of handling mutiple heaps of memory. It is also
5801 capable of saving a heap to a file, and then mapping it back in later.
5802 This can be used to greatly speedup the startup of GDB by using a
5803 pre-parsed symbol table which lives in a mmalloc managed heap. For
5804 more details, please read mmalloc/mmalloc.texi.
5808 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5809 'help info proc' for details.
5811 * MIPS ecoff symbol table format
5813 The code that reads MIPS symbol table format is now supported on all hosts.
5814 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5817 * File name changes for MS-DOS
5819 Many files in the config directories have been renamed to make it easier to
5820 support GDB on MS-DOSe systems (which have very restrictive file name
5821 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5822 environment) is close to working but has some remaining problems. Note
5823 that debugging of DOS programs is not supported, due to limitations
5824 in the ``operating system'', but it can be used to host cross-debugging.
5826 * Cross byte order fixes
5828 Many fixes have been made to support cross debugging of Sparc and MIPS
5829 targets from hosts whose byte order differs.
5831 * New -mapped and -readnow options
5833 If memory-mapped files are available on your system through the 'mmap'
5834 system call, you can use the -mapped option on the `file' or
5835 `symbol-file' commands to cause GDB to write the symbols from your
5836 program into a reusable file. If the program you are debugging is
5837 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5838 Future GDB debugging sessions will notice the presence of this file,
5839 and will quickly map in symbol information from it, rather than reading
5840 the symbol table from the executable program. Using the '-mapped'
5841 option in a GDB `file' or `symbol-file' command has the same effect as
5842 starting GDB with the '-mapped' command-line option.
5844 You can cause GDB to read the entire symbol table immediately by using
5845 the '-readnow' option with any of the commands that load symbol table
5846 information (or on the GDB command line). This makes the command
5847 slower, but makes future operations faster.
5849 The -mapped and -readnow options are typically combined in order to
5850 build a `fred.syms' file that contains complete symbol information.
5851 A simple GDB invocation to do nothing but build a `.syms' file for future
5854 gdb -batch -nx -mapped -readnow programname
5856 The `.syms' file is specific to the host machine on which GDB is run.
5857 It holds an exact image of GDB's internal symbol table. It cannot be
5858 shared across multiple host platforms.
5860 * longjmp() handling
5862 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5863 siglongjmp() without losing control. This feature has not yet been ported to
5864 all systems. It currently works on many 386 platforms, all MIPS-based
5865 platforms (SGI, DECstation, etc), and Sun3/4.
5869 Preliminary work has been put in to support the new Solaris OS from Sun. At
5870 this time, it can control and debug processes, but it is not capable of
5875 As always, many many bug fixes. The major areas were with g++, and mipsread.
5876 People using the MIPS-based platforms should experience fewer mysterious
5877 crashes and trashed symbol tables.
5879 *** Changes in GDB-4.4:
5881 * New machines supported (host and target)
5883 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5885 BSD Reno on Vax vax-dec-bsd
5886 Ultrix on Vax vax-dec-ultrix
5888 * New machines supported (target)
5890 AMD 29000 embedded, using EBMON a29k-none-none
5894 GDB continues to improve its handling of C++. `References' work better.
5895 The demangler has also been improved, and now deals with symbols mangled as
5896 per the Annotated C++ Reference Guide.
5898 GDB also now handles `stabs' symbol information embedded in MIPS
5899 `ecoff' symbol tables. Since the ecoff format was not easily
5900 extensible to handle new languages such as C++, this appeared to be a
5901 good way to put C++ debugging info into MIPS binaries. This option
5902 will be supported in the GNU C compiler, version 2, when it is
5905 * New features for SVR4
5907 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5908 shared libraries. Debugging dynamically linked programs should present
5909 only minor differences from debugging statically linked programs.
5911 The `info proc' command will print out information about any process
5912 on an SVR4 system (including the one you are debugging). At the moment,
5913 it prints the address mappings of the process.
5915 If you bring up GDB on another SVR4 system, please send mail to
5916 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5918 * Better dynamic linking support in SunOS
5920 Reading symbols from shared libraries which contain debugging symbols
5921 now works properly. However, there remain issues such as automatic
5922 skipping of `transfer vector' code during function calls, which
5923 make it harder to debug code in a shared library, than to debug the
5924 same code linked statically.
5928 GDB is now using the latest `getopt' routines from the FSF. This
5929 version accepts the -- prefix for options with long names. GDB will
5930 continue to accept the old forms (-option and +option) as well.
5931 Various single letter abbreviations for options have been explicity
5932 added to the option table so that they won't get overshadowed in the
5933 future by other options that begin with the same letter.
5937 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5938 Many assorted bugs have been handled. Many more remain to be handled.
5939 See the various ChangeLog files (primarily in gdb and bfd) for details.
5942 *** Changes in GDB-4.3:
5944 * New machines supported (host and target)
5946 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5947 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5948 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5950 * Almost SCO Unix support
5952 We had hoped to support:
5953 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5954 (except for core file support), but we discovered very late in the release
5955 that it has problems with process groups that render gdb unusable. Sorry
5956 about that. I encourage people to fix it and post the fixes.
5958 * Preliminary ELF and DWARF support
5960 GDB can read ELF object files on System V Release 4, and can handle
5961 debugging records for C, in DWARF format, in ELF files. This support
5962 is preliminary. If you bring up GDB on another SVR4 system, please
5963 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5968 GDB now uses the latest `readline' library. One user-visible change
5969 is that two tabs will list possible command completions, which previously
5970 required typing M-? (meta-question mark, or ESC ?).
5974 The `stepi' bug that many of you noticed has been squashed.
5975 Many bugs in C++ have been handled. Many more remain to be handled.
5976 See the various ChangeLog files (primarily in gdb and bfd) for details.
5978 * State of the MIPS world (in case you wondered):
5980 GDB can understand the symbol tables emitted by the compilers
5981 supplied by most vendors of MIPS-based machines, including DEC. These
5982 symbol tables are in a format that essentially nobody else uses.
5984 Some versions of gcc come with an assembler post-processor called
5985 mips-tfile. This program is required if you want to do source-level
5986 debugging of gcc-compiled programs. I believe FSF does not ship
5987 mips-tfile with gcc version 1, but it will eventually come with gcc
5990 Debugging of g++ output remains a problem. g++ version 1.xx does not
5991 really support it at all. (If you're lucky, you should be able to get
5992 line numbers and stack traces to work, but no parameters or local
5993 variables.) With some work it should be possible to improve the
5996 When gcc version 2 is released, you will have somewhat better luck.
5997 However, even then you will get confusing results for inheritance and
6000 We will eventually provide full debugging of g++ output on
6001 DECstations. This will probably involve some kind of stabs-in-ecoff
6002 encapulation, but the details have not been worked out yet.
6005 *** Changes in GDB-4.2:
6007 * Improved configuration
6009 Only one copy of `configure' exists now, and it is not self-modifying.
6010 Porting BFD is simpler.
6014 The `step' and `next' commands now only stop at the first instruction
6015 of a source line. This prevents the multiple stops that used to occur
6016 in switch statements, for-loops, etc. `Step' continues to stop if a
6017 function that has debugging information is called within the line.
6021 Lots of small bugs fixed. More remain.
6023 * New host supported (not target)
6025 Intel 386 PC clone running Mach i386-none-mach
6028 *** Changes in GDB-4.1:
6030 * Multiple source language support
6032 GDB now has internal scaffolding to handle several source languages.
6033 It determines the type of each source file from its filename extension,
6034 and will switch expression parsing and number formatting to match the
6035 language of the function in the currently selected stack frame.
6036 You can also specifically set the language to be used, with
6037 `set language c' or `set language modula-2'.
6041 GDB now has preliminary support for the GNU Modula-2 compiler,
6042 currently under development at the State University of New York at
6043 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6044 continue through the fall of 1991 and into 1992.
6046 Other Modula-2 compilers are currently not supported, and attempting to
6047 debug programs compiled with them will likely result in an error as the
6048 symbol table is read. Feel free to work on it, though!
6050 There are hooks in GDB for strict type checking and range checking,
6051 in the `Modula-2 philosophy', but they do not currently work.
6055 GDB can now write to executable and core files (e.g. patch
6056 a variable's value). You must turn this switch on, specify
6057 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6058 by assigning a new value to a variable. Modifications take
6061 * Automatic SunOS shared library reading
6063 When you run your program, GDB automatically determines where its
6064 shared libraries (if any) have been loaded, and reads their symbols.
6065 The `share' command is no longer needed. This also works when
6066 examining core files.
6070 You can specify the number of lines that the `list' command shows.
6073 * New machines supported (host and target)
6075 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6076 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6077 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6079 * New hosts supported (not targets)
6081 IBM RT/PC: romp-ibm-aix or rtpc
6083 * New targets supported (not hosts)
6085 AMD 29000 embedded with COFF a29k-none-coff
6086 AMD 29000 embedded with a.out a29k-none-aout
6087 Ultracomputer remote kernel debug a29k-nyu-kern
6089 * New remote interfaces
6095 *** Changes in GDB-4.0:
6099 Wide output is wrapped at good places to make the output more readable.
6101 Gdb now supports cross-debugging from a host machine of one type to a
6102 target machine of another type. Communication with the target system
6103 is over serial lines. The ``target'' command handles connecting to the
6104 remote system; the ``load'' command will download a program into the
6105 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6106 also supports debugging of realtime processes running under VxWorks,
6107 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6108 stub on the target system.
6110 New CPUs supported include the AMD 29000 and Intel 960.
6112 GDB now reads object files and symbol tables via a ``binary file''
6113 library, which allows a single copy of GDB to debug programs of multiple
6114 object file types such as a.out and coff.
6116 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6117 refcard.dvi and refcard.ps are available to format it).
6120 * Control-Variable user interface simplified
6122 All variables that control the operation of the debugger can be set
6123 by the ``set'' command, and displayed by the ``show'' command.
6125 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6126 ``Show prompt'' produces the response:
6127 Gdb's prompt is new-gdb=>.
6129 What follows are the NEW set commands. The command ``help set'' will
6130 print a complete list of old and new set commands. ``help set FOO''
6131 will give a longer description of the variable FOO. ``show'' will show
6132 all of the variable descriptions and their current settings.
6134 confirm on/off: Enables warning questions for operations that are
6135 hard to recover from, e.g. rerunning the program while
6136 it is already running. Default is ON.
6138 editing on/off: Enables EMACS style command line editing
6139 of input. Previous lines can be recalled with
6140 control-P, the current line can be edited with control-B,
6141 you can search for commands with control-R, etc.
6144 history filename NAME: NAME is where the gdb command history
6145 will be stored. The default is .gdb_history,
6146 or the value of the environment variable
6149 history size N: The size, in commands, of the command history. The
6150 default is 256, or the value of the environment variable
6153 history save on/off: If this value is set to ON, the history file will
6154 be saved after exiting gdb. If set to OFF, the
6155 file will not be saved. The default is OFF.
6157 history expansion on/off: If this value is set to ON, then csh-like
6158 history expansion will be performed on
6159 command line input. The default is OFF.
6161 radix N: Sets the default radix for input and output. It can be set
6162 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6163 in the current radix, so "set radix 10" is always a no-op.
6165 height N: This integer value is the number of lines on a page. Default
6166 is 24, the current `stty rows'' setting, or the ``li#''
6167 setting from the termcap entry matching the environment
6170 width N: This integer value is the number of characters on a line.
6171 Default is 80, the current `stty cols'' setting, or the ``co#''
6172 setting from the termcap entry matching the environment
6175 Note: ``set screensize'' is obsolete. Use ``set height'' and
6176 ``set width'' instead.
6178 print address on/off: Print memory addresses in various command displays,
6179 such as stack traces and structure values. Gdb looks
6180 more ``symbolic'' if you turn this off; it looks more
6181 ``machine level'' with it on. Default is ON.
6183 print array on/off: Prettyprint arrays. New convenient format! Default
6186 print demangle on/off: Print C++ symbols in "source" form if on,
6189 print asm-demangle on/off: Same, for assembler level printouts
6192 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6195 * Support for Epoch Environment.
6197 The epoch environment is a version of Emacs v18 with windowing. One
6198 new command, ``inspect'', is identical to ``print'', except that if you
6199 are running in the epoch environment, the value is printed in its own
6203 * Support for Shared Libraries
6205 GDB can now debug programs and core files that use SunOS shared libraries.
6206 Symbols from a shared library cannot be referenced
6207 before the shared library has been linked with the program (this
6208 happens after you type ``run'' and before the function main() is entered).
6209 At any time after this linking (including when examining core files
6210 from dynamically linked programs), gdb reads the symbols from each
6211 shared library when you type the ``sharedlibrary'' command.
6212 It can be abbreviated ``share''.
6214 sharedlibrary REGEXP: Load shared object library symbols for files
6215 matching a unix regular expression. No argument
6216 indicates to load symbols for all shared libraries.
6218 info sharedlibrary: Status of loaded shared libraries.
6223 A watchpoint stops execution of a program whenever the value of an
6224 expression changes. Checking for this slows down execution
6225 tremendously whenever you are in the scope of the expression, but is
6226 quite useful for catching tough ``bit-spreader'' or pointer misuse
6227 problems. Some machines such as the 386 have hardware for doing this
6228 more quickly, and future versions of gdb will use this hardware.
6230 watch EXP: Set a watchpoint (breakpoint) for an expression.
6232 info watchpoints: Information about your watchpoints.
6234 delete N: Deletes watchpoint number N (same as breakpoints).
6235 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6236 enable N: Re-enables watchpoint number N (same as breakpoints).
6239 * C++ multiple inheritance
6241 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6244 * C++ exception handling
6246 Gdb now supports limited C++ exception handling. Besides the existing
6247 ability to breakpoint on an exception handler, gdb can breakpoint on
6248 the raising of an exception (before the stack is peeled back to the
6251 catch FOO: If there is a FOO exception handler in the dynamic scope,
6252 set a breakpoint to catch exceptions which may be raised there.
6253 Multiple exceptions (``catch foo bar baz'') may be caught.
6255 info catch: Lists all exceptions which may be caught in the
6256 current stack frame.
6259 * Minor command changes
6261 The command ``call func (arg, arg, ...)'' now acts like the print
6262 command, except it does not print or save a value if the function's result
6263 is void. This is similar to dbx usage.
6265 The ``up'' and ``down'' commands now always print the frame they end up
6266 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6267 frames without printing.
6269 * New directory command
6271 'dir' now adds directories to the FRONT of the source search path.
6272 The path starts off empty. Source files that contain debug information
6273 about the directory in which they were compiled can be found even
6274 with an empty path; Sun CC and GCC include this information. If GDB can't
6275 find your source file in the current directory, type "dir .".
6277 * Configuring GDB for compilation
6279 For normal use, type ``./configure host''. See README or gdb.texinfo
6282 GDB now handles cross debugging. If you are remotely debugging between
6283 two different machines, type ``./configure host -target=targ''.
6284 Host is the machine where GDB will run; targ is the machine
6285 where the program that you are debugging will run.