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 * Thread names in remote protocol
99 The reply to qXfer:threads:read may now include a name attribute for each
102 *** Changes in GDB 7.10
104 * Support for process record-replay and reverse debugging on aarch64*-linux*
105 targets has been added. GDB now supports recording of A64 instruction set
106 including advance SIMD instructions.
108 * Support for Sun's version of the "stabs" debug file format has been removed.
110 * GDB now honors the content of the file /proc/PID/coredump_filter
111 (PID is the process ID) on GNU/Linux systems. This file can be used
112 to specify the types of memory mappings that will be included in a
113 corefile. For more information, please refer to the manual page of
114 "core(5)". GDB also has a new command: "set use-coredump-filter
115 on|off". It allows to set whether GDB will read the content of the
116 /proc/PID/coredump_filter file when generating a corefile.
118 * The "info os" command on GNU/Linux can now display information on
120 "info os cpus" Listing of all cpus/cores on the system
122 * GDB has two new commands: "set serial parity odd|even|none" and
123 "show serial parity". These allows to set or show parity for the
126 * The "info source" command now displays the producer string if it was
127 present in the debug info. This typically includes the compiler version
128 and may include things like its command line arguments.
130 * The "info dll", an alias of the "info sharedlibrary" command,
131 is now available on all platforms.
133 * Directory names supplied to the "set sysroot" commands may be
134 prefixed with "target:" to tell GDB to access shared libraries from
135 the target system, be it local or remote. This replaces the prefix
136 "remote:". The default sysroot has been changed from "" to
137 "target:". "remote:" is automatically converted to "target:" for
138 backward compatibility.
140 * The system root specified by "set sysroot" will be prepended to the
141 filename of the main executable (if reported to GDB as absolute by
142 the operating system) when starting processes remotely, and when
143 attaching to already-running local or remote processes.
145 * GDB now supports automatic location and retrieval of executable
146 files from remote targets. Remote debugging can now be initiated
147 using only a "target remote" or "target extended-remote" command
148 (no "set sysroot" or "file" commands are required). See "New remote
151 * The "dump" command now supports verilog hex format.
153 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
155 * On GNU/Linux, GDB and gdbserver are now able to access executable
156 and shared library files without a "set sysroot" command when
157 attaching to processes running in different mount namespaces from
158 the debugger. This makes it possible to attach to processes in
159 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
160 See "New remote packets" below.
162 * The "tui reg" command now provides completion for all of the
163 available register groups, including target specific groups.
165 * The HISTSIZE environment variable is no longer read when determining
166 the size of GDB's command history. GDB now instead reads the dedicated
167 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
168 disables truncation of command history. Non-numeric values of GDBHISTSIZE
173 ** Memory ports can now be unbuffered.
177 ** gdb.Objfile objects have a new attribute "username",
178 which is the name of the objfile as specified by the user,
179 without, for example, resolving symlinks.
180 ** You can now write frame unwinders in Python.
181 ** gdb.Type objects have a new method "optimized_out",
182 returning optimized out gdb.Value instance of this type.
183 ** gdb.Value objects have new methods "reference_value" and
184 "const_value" which return a reference to the value and a
185 "const" version of the value respectively.
189 maint print symbol-cache
190 Print the contents of the symbol cache.
192 maint print symbol-cache-statistics
193 Print statistics of symbol cache usage.
195 maint flush-symbol-cache
196 Flush the contents of the symbol cache.
200 Start branch trace recording using Branch Trace Store (BTS) format.
203 Evaluate expression by using the compiler and print result.
207 Explicit commands for enabling and disabling tui mode.
210 set mpx bound on i386 and amd64
211 Support for bound table investigation on Intel(R) MPX enabled applications.
215 Start branch trace recording using Intel(R) Processor Trace format.
218 Print information about branch tracing internals.
220 maint btrace packet-history
221 Print the raw branch tracing data.
223 maint btrace clear-packet-history
224 Discard the stored raw branch tracing data.
227 Discard all branch tracing data. It will be fetched and processed
228 anew by the next "record" command.
233 Renamed from "set debug dwarf2-die".
235 Renamed from "show debug dwarf2-die".
238 Renamed from "set debug dwarf2-read".
239 show debug dwarf-read
240 Renamed from "show debug dwarf2-read".
242 maint set dwarf always-disassemble
243 Renamed from "maint set dwarf2 always-disassemble".
244 maint show dwarf always-disassemble
245 Renamed from "maint show dwarf2 always-disassemble".
247 maint set dwarf max-cache-age
248 Renamed from "maint set dwarf2 max-cache-age".
249 maint show dwarf max-cache-age
250 Renamed from "maint show dwarf2 max-cache-age".
253 show debug dwarf-line
254 Control display of debugging info regarding DWARF line processing.
258 Set the maximum number of candidates to be considered during
259 completion. The default value is 200. This limit allows GDB
260 to avoid generating large completion lists, the computation of
261 which can cause the debugger to become temporarily unresponsive.
263 set history remove-duplicates
264 show history remove-duplicates
265 Control the removal of duplicate history entries.
267 maint set symbol-cache-size
268 maint show symbol-cache-size
269 Control the size of the symbol cache.
271 set|show record btrace bts buffer-size
272 Set and show the size of the ring buffer used for branch tracing in
274 The obtained size may differ from the requested size. Use "info
275 record" to see the obtained buffer size.
277 set debug linux-namespaces
278 show debug linux-namespaces
279 Control display of debugging info regarding Linux namespaces.
281 set|show record btrace pt buffer-size
282 Set and show the size of the ring buffer used for branch tracing in
283 Intel(R) Processor Trace format.
284 The obtained size may differ from the requested size. Use "info
285 record" to see the obtained buffer size.
287 maint set|show btrace pt skip-pad
288 Set and show whether PAD packets are skipped when computing the
291 * The command 'thread apply all' can now support new option '-ascending'
292 to call its specified command for all threads in ascending order.
294 * Python/Guile scripting
296 ** GDB now supports auto-loading of Python/Guile scripts contained in the
297 special section named `.debug_gdb_scripts'.
301 qXfer:btrace-conf:read
302 Return the branch trace configuration for the current thread.
304 Qbtrace-conf:bts:size
305 Set the requested ring buffer size for branch tracing in BTS format.
308 Enable Intel(R) Procesor Trace-based branch tracing for the current
309 process. The remote stub reports support for this packet to GDB's
313 Set the requested ring buffer size for branch tracing in Intel(R) Processor
317 Indicates a memory breakpoint instruction was executed, irrespective
318 of whether it was GDB that planted the breakpoint or the breakpoint
319 is hardcoded in the program. This is required for correct non-stop
323 Indicates the target stopped for a hardware breakpoint. This is
324 required for correct non-stop mode operation.
327 Return information about files on the remote system.
330 Return the full absolute name of the file that was executed to
331 create a process running on the remote system.
334 Select the filesystem on which vFile: operations with filename
335 arguments will operate. This is required for GDB to be able to
336 access files on remote targets where the remote stub does not
337 share a common filesystem with the inferior(s).
340 Indicates that a fork system call was executed.
343 Indicates that a vfork system call was executed.
345 vforkdone stop reason
346 Indicates that a vfork child of the specified process has executed
347 an exec or exit, allowing the vfork parent to resume execution.
349 fork-events and vfork-events features in qSupported
350 The qSupported packet allows GDB to request support for fork and
351 vfork events using new 'gdbfeatures' fork-events and vfork-events,
352 and the qSupported response can contain the corresponding
353 'stubfeatures'. Set and show commands can be used to display
354 whether these features are enabled.
356 * Extended-remote fork events
358 ** GDB now has support for fork events on extended-remote Linux
359 targets. For targets with Linux kernels 2.5.60 and later, this
360 enables follow-fork-mode and detach-on-fork for both fork and
361 vfork, as well as fork and vfork catchpoints.
363 * The info record command now shows the recording format and the
364 branch tracing configuration for the current thread when using
365 the btrace record target.
366 For the BTS format, it shows the ring buffer size.
368 * GDB now has support for DTrace USDT (Userland Static Defined
369 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
371 * GDB now supports access to vector registers on S/390 GNU/Linux
374 * Removed command line options
376 -xdb HP-UX XDB compatibility mode.
378 * Removed targets and native configurations
380 HP/PA running HP-UX hppa*-*-hpux*
381 Itanium running HP-UX ia64-*-hpux*
383 * New configure options
386 This configure option allows the user to build GDB with support for
387 Intel(R) Processor Trace (default: auto). This requires libipt.
389 --with-libipt-prefix=PATH
390 Specify the path to the version of libipt that GDB should use.
391 $PATH/include should contain the intel-pt.h header and
392 $PATH/lib should contain the libipt.so library.
394 *** Changes in GDB 7.9.1
398 ** Xmethods can now specify a result type.
400 *** Changes in GDB 7.9
402 * GDB now supports hardware watchpoints on x86 GNU Hurd.
406 ** You can now access frame registers from Python scripts.
407 ** New attribute 'producer' for gdb.Symtab objects.
408 ** gdb.Objfile objects have a new attribute "progspace",
409 which is the gdb.Progspace object of the containing program space.
410 ** gdb.Objfile objects have a new attribute "owner".
411 ** gdb.Objfile objects have a new attribute "build_id",
412 which is the build ID generated when the file was built.
413 ** gdb.Objfile objects have a new method "add_separate_debug_file".
414 ** A new event "gdb.clear_objfiles" has been added, triggered when
415 selecting a new file to debug.
416 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
417 ** New function gdb.lookup_objfile.
419 New events which are triggered when GDB modifies the state of the
422 ** gdb.events.inferior_call_pre: Function call is about to be made.
423 ** gdb.events.inferior_call_post: Function call has just been made.
424 ** gdb.events.memory_changed: A memory location has been altered.
425 ** gdb.events.register_changed: A register has been altered.
427 * New Python-based convenience functions:
429 ** $_caller_is(name [, number_of_frames])
430 ** $_caller_matches(regexp [, number_of_frames])
431 ** $_any_caller_is(name [, number_of_frames])
432 ** $_any_caller_matches(regexp [, number_of_frames])
434 * GDB now supports the compilation and injection of source code into
435 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
436 to compile the source code to object code, and if successful, inject
437 and execute that code within the current context of the inferior.
438 Currently the C language is supported. The commands used to
439 interface with this new feature are:
441 compile code [-raw|-r] [--] [source code]
442 compile file [-raw|-r] filename
446 demangle [-l language] [--] name
447 Demangle "name" in the specified language, or the current language
448 if elided. This command is renamed from the "maint demangle" command.
449 The latter is kept as a no-op to avoid "maint demangle" being interpreted
450 as "maint demangler-warning".
452 queue-signal signal-name-or-number
453 Queue a signal to be delivered to the thread when it is resumed.
455 add-auto-load-scripts-directory directory
456 Add entries to the list of directories from which to load auto-loaded
459 maint print user-registers
460 List all currently available "user" registers.
462 compile code [-r|-raw] [--] [source code]
463 Compile, inject, and execute in the inferior the executable object
464 code produced by compiling the provided source code.
466 compile file [-r|-raw] filename
467 Compile and inject into the inferior the executable object code
468 produced by compiling the source code stored in the filename
471 * On resume, GDB now always passes the signal the program had stopped
472 for to the thread the signal was sent to, even if the user changed
473 threads before resuming. Previously GDB would often (but not
474 always) deliver the signal to the thread that happens to be current
477 * Conversely, the "signal" command now consistently delivers the
478 requested signal to the current thread. GDB now asks for
479 confirmation if the program had stopped for a signal and the user
480 switched threads meanwhile.
482 * "breakpoint always-inserted" modes "off" and "auto" merged.
484 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
485 won't remove breakpoints from the target until all threads stop,
486 even in non-stop mode. The "auto" mode has been removed, and "off"
487 is now the default mode.
491 set debug symbol-lookup
492 show debug symbol-lookup
493 Control display of debugging info regarding symbol lookup.
497 ** The -list-thread-groups command outputs an exit-code field for
498 inferiors that have exited.
502 MIPS SDE mips*-sde*-elf*
506 Support for these obsolete configurations has been removed.
508 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
509 SGI Irix-5.x mips-*-irix5*
510 SGI Irix-6.x mips-*-irix6*
511 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
512 VAX running Ultrix vax-*-ultrix*
514 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
515 and "assf"), have been removed. Use the "sharedlibrary" command, or
516 its alias "share", instead.
518 *** Changes in GDB 7.8
520 * New command line options
523 This is an alias for the --data-directory option.
525 * GDB supports printing and modifying of variable length automatic arrays
526 as specified in ISO C99.
528 * The ARM simulator now supports instruction level tracing
529 with or without disassembly.
533 GDB now has support for scripting using Guile. Whether this is
534 available is determined at configure time.
535 Guile version 2.0 or greater is required.
536 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
538 * New commands (for set/show, see "New options" below)
542 Invoke CODE by passing it to the Guile interpreter.
546 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
548 info auto-load guile-scripts [regexp]
549 Print the list of automatically loaded Guile scripts.
551 * The source command is now capable of sourcing Guile scripts.
552 This feature is dependent on the debugger being built with Guile support.
556 set print symbol-loading (off|brief|full)
557 show print symbol-loading
558 Control whether to print informational messages when loading symbol
559 information for a file. The default is "full", but when debugging
560 programs with large numbers of shared libraries the amount of output
563 set guile print-stack (none|message|full)
564 show guile print-stack
565 Show a stack trace when an error is encountered in a Guile script.
567 set auto-load guile-scripts (on|off)
568 show auto-load guile-scripts
569 Control auto-loading of Guile script files.
571 maint ada set ignore-descriptive-types (on|off)
572 maint ada show ignore-descriptive-types
573 Control whether the debugger should ignore descriptive types in Ada
574 programs. The default is not to ignore the descriptive types. See
575 the user manual for more details on descriptive types and the intended
576 usage of this option.
578 set auto-connect-native-target
580 Control whether GDB is allowed to automatically connect to the
581 native target for the run, attach, etc. commands when not connected
582 to any target yet. See also "target native" below.
584 set record btrace replay-memory-access (read-only|read-write)
585 show record btrace replay-memory-access
586 Control what memory accesses are allowed during replay.
588 maint set target-async (on|off)
589 maint show target-async
590 This controls whether GDB targets operate in synchronous or
591 asynchronous mode. Normally the default is asynchronous, if it is
592 available; but this can be changed to more easily debug problems
593 occurring only in synchronous mode.
595 set mi-async (on|off)
597 Control whether MI asynchronous mode is preferred. This supersedes
598 "set target-async" of previous GDB versions.
600 * "set target-async" is deprecated as a CLI option and is now an alias
601 for "set mi-async" (only puts MI into async mode).
603 * Background execution commands (e.g., "c&", "s&", etc.) are now
604 possible ``out of the box'' if the target supports them. Previously
605 the user would need to explicitly enable the possibility with the
606 "set target-async on" command.
608 * New features in the GDB remote stub, GDBserver
610 ** New option --debug-format=option1[,option2,...] allows one to add
611 additional text to each output. At present only timestamps
612 are supported: --debug-format=timestamps.
613 Timestamps can also be turned on with the
614 "monitor set debug-format timestamps" command from GDB.
616 * The 'record instruction-history' command now starts counting instructions
617 at one. This also affects the instruction ranges reported by the
618 'record function-call-history' command when given the /i modifier.
620 * The command 'record function-call-history' supports a new modifier '/c' to
621 indent the function names based on their call stack depth.
622 The fields for the '/i' and '/l' modifier have been reordered.
623 The source line range is now prefixed with 'at'.
624 The instruction range is now prefixed with 'inst'.
625 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
626 "record instruction-history" and "list" commands.
628 * The ranges given as arguments to the 'record function-call-history' and
629 'record instruction-history' commands are now inclusive.
631 * The btrace record target now supports the 'record goto' command.
632 For locations inside the execution trace, the back trace is computed
633 based on the information stored in the execution trace.
635 * The btrace record target supports limited reverse execution and replay.
636 The target does not record data and therefore does not allow reading
639 * The "catch syscall" command now works on s390*-linux* targets.
641 * The "compare-sections" command is no longer specific to target
642 remote. It now works with all targets.
644 * All native targets are now consistently called "native".
645 Consequently, the "target child", "target GNU", "target djgpp",
646 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
647 commands have been replaced with "target native". The QNX/NTO port
648 leaves the "procfs" target in place and adds a "native" target for
649 consistency with other ports. The impact on users should be minimal
650 as these commands previously either throwed an error, or were
651 no-ops. The target's name is visible in the output of the following
652 commands: "help target", "info target", "info files", "maint print
655 * The "target native" command now connects to the native target. This
656 can be used to launch native programs even when "set
657 auto-connect-native-target" is set to off.
659 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
661 * Support for Intel(R) AVX-512 registers on GNU/Linux.
662 Support displaying and modifying Intel(R) AVX-512 registers
663 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
667 qXfer:btrace:read's annex
668 The qXfer:btrace:read packet supports a new annex 'delta' to read
669 branch trace incrementally.
673 ** Valid Python operations on gdb.Value objects representing
674 structs/classes invoke the corresponding overloaded operators if
676 ** New `Xmethods' feature in the Python API. Xmethods are
677 additional methods or replacements for existing methods of a C++
678 class. This feature is useful for those cases where a method
679 defined in C++ source code could be inlined or optimized out by
680 the compiler, making it unavailable to GDB.
683 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
685 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
686 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
687 its alias "share", instead.
689 * The commands "set remotebaud" and "show remotebaud" are no longer
690 supported. Use "set serial baud" and "show serial baud" (respectively)
695 ** A new option "-gdb-set mi-async" replaces "-gdb-set
696 target-async". The latter is left as a deprecated alias of the
697 former for backward compatibility. If the target supports it,
698 CLI background execution commands are now always possible by
699 default, independently of whether the frontend stated a
700 preference for asynchronous execution with "-gdb-set mi-async".
701 Previously "-gdb-set target-async off" affected both MI execution
702 commands and CLI execution commands.
704 *** Changes in GDB 7.7
706 * Improved support for process record-replay and reverse debugging on
707 arm*-linux* targets. Support for thumb32 and syscall instruction
708 recording has been added.
710 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
712 * GDB now supports Fission DWP file format version 2.
713 http://gcc.gnu.org/wiki/DebugFission
715 * New convenience function "$_isvoid", to check whether an expression
716 is void. A void expression is an expression where the type of the
717 result is "void". For example, some convenience variables may be
718 "void" when evaluated (e.g., "$_exitcode" before the execution of
719 the program being debugged; or an undefined convenience variable).
720 Another example, when calling a function whose return type is
723 * The "maintenance print objfiles" command now takes an optional regexp.
725 * The "catch syscall" command now works on arm*-linux* targets.
727 * GDB now consistently shows "<not saved>" when printing values of
728 registers the debug info indicates have not been saved in the frame
729 and there's nowhere to retrieve them from
730 (callee-saved/call-clobbered registers):
735 (gdb) info registers rax
738 Before, the former would print "<optimized out>", and the latter
739 "*value not available*".
741 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
746 ** Frame filters and frame decorators have been added.
747 ** Temporary breakpoints are now supported.
748 ** Line tables representation has been added.
749 ** New attribute 'parent_type' for gdb.Field objects.
750 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
751 ** New attribute 'name' for gdb.Type objects.
755 Nios II ELF nios2*-*-elf
756 Nios II GNU/Linux nios2*-*-linux
757 Texas Instruments MSP430 msp430*-*-elf
759 * Removed native configurations
761 Support for these a.out NetBSD and OpenBSD obsolete configurations has
762 been removed. ELF variants of these configurations are kept supported.
764 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
765 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
766 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
767 i[34567]86-*-openbsd3.[0-3]
768 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
769 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
770 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
774 Like "catch throw", but catches a re-thrown exception.
776 Renamed from old "maint check-symtabs".
778 Perform consistency checks on symtabs.
780 Expand symtabs matching an optional regexp.
783 Display the details of GDB configure-time options.
785 maint set|show per-command
786 maint set|show per-command space
787 maint set|show per-command time
788 maint set|show per-command symtab
789 Enable display of per-command gdb resource usage.
791 remove-symbol-file FILENAME
792 remove-symbol-file -a ADDRESS
793 Remove a symbol file added via add-symbol-file. The file to remove
794 can be identified by its filename or by an address that lies within
795 the boundaries of this symbol file in memory.
798 info exceptions REGEXP
799 Display the list of Ada exceptions defined in the program being
800 debugged. If provided, only the exceptions whose names match REGEXP
805 set debug symfile off|on
807 Control display of debugging info regarding reading symbol files and
808 symbol tables within those files
810 set print raw frame-arguments
811 show print raw frame-arguments
812 Set/show whether to print frame arguments in raw mode,
813 disregarding any defined pretty-printers.
815 set remote trace-status-packet
816 show remote trace-status-packet
817 Set/show the use of remote protocol qTStatus packet.
821 Control display of debugging messages related to Nios II targets.
825 Control whether target-assisted range stepping is enabled.
827 set startup-with-shell
828 show startup-with-shell
829 Specifies whether Unix child processes are started via a shell or
834 Use the target memory cache for accesses to the code segment. This
835 improves performance of remote debugging (particularly disassembly).
837 * You can now use a literal value 'unlimited' for options that
838 interpret 0 or -1 as meaning "unlimited". E.g., "set
839 trace-buffer-size unlimited" is now an alias for "set
840 trace-buffer-size -1" and "set height unlimited" is now an alias for
843 * The "set debug symtab-create" debugging option of GDB has been changed to
844 accept a verbosity level. 0 means "off", 1 provides basic debugging
845 output, and values of 2 or greater provides more verbose output.
847 * New command-line options
849 Display the details of GDB configure-time options.
851 * The command 'tsave' can now support new option '-ctf' to save trace
852 buffer in Common Trace Format.
854 * Newly installed $prefix/bin/gcore acts as a shell interface for the
857 * GDB now implements the the C++ 'typeid' operator.
859 * The new convenience variable $_exception holds the exception being
860 thrown or caught at an exception-related catchpoint.
862 * The exception-related catchpoints, like "catch throw", now accept a
863 regular expression which can be used to filter exceptions by type.
865 * The new convenience variable $_exitsignal is automatically set to
866 the terminating signal number when the program being debugged dies
867 due to an uncaught signal.
871 ** All MI commands now accept an optional "--language" option.
872 Support for this feature can be verified by using the "-list-features"
873 command, which should contain "language-option".
875 ** The new command -info-gdb-mi-command allows the user to determine
876 whether a GDB/MI command is supported or not.
878 ** The "^error" result record returned when trying to execute an undefined
879 GDB/MI command now provides a variable named "code" whose content is the
880 "undefined-command" error code. Support for this feature can be verified
881 by using the "-list-features" command, which should contain
882 "undefined-command-error-code".
884 ** The -trace-save MI command can optionally save trace buffer in Common
887 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
889 ** The command -data-list-register-values now accepts an optional
890 "--skip-unavailable" option. When used, only the available registers
893 ** The new command -trace-frame-collected dumps collected variables,
894 computed expressions, tvars, memory and registers in a traceframe.
896 ** The commands -stack-list-locals, -stack-list-arguments and
897 -stack-list-variables now accept an option "--skip-unavailable".
898 When used, only the available locals or arguments are displayed.
900 ** The -exec-run command now accepts an optional "--start" option.
901 When used, the command follows the same semantics as the "start"
902 command, stopping the program's execution at the start of its
903 main subprogram. Support for this feature can be verified using
904 the "-list-features" command, which should contain
905 "exec-run-start-option".
907 ** The new commands -catch-assert and -catch-exceptions insert
908 catchpoints stopping the program when Ada exceptions are raised.
910 ** The new command -info-ada-exceptions provides the equivalent of
911 the new "info exceptions" command.
913 * New system-wide configuration scripts
914 A GDB installation now provides scripts suitable for use as system-wide
915 configuration scripts for the following systems:
919 * GDB now supports target-assigned range stepping with remote targets.
920 This improves the performance of stepping source lines by reducing
921 the number of control packets from/to GDB. See "New remote packets"
924 * GDB now understands the element 'tvar' in the XML traceframe info.
925 It has the id of the collected trace state variables.
927 * On S/390 targets that provide the transactional-execution feature,
928 the program interruption transaction diagnostic block (TDB) is now
929 represented as a number of additional "registers" in GDB.
935 The vCont packet supports a new 'r' action, that tells the remote
936 stub to step through an address range itself, without GDB
937 involvemement at each single-step.
939 qXfer:libraries-svr4:read's annex
940 The previously unused annex of the qXfer:libraries-svr4:read packet
941 is now used to support passing an argument list. The remote stub
942 reports support for this argument list to GDB's qSupported query.
943 The defined arguments are "start" and "prev", used to reduce work
944 necessary for library list updating, resulting in significant
947 * New features in the GDB remote stub, GDBserver
949 ** GDBserver now supports target-assisted range stepping. Currently
950 enabled on x86/x86_64 GNU/Linux targets.
952 ** GDBserver now adds element 'tvar' in the XML in the reply to
953 'qXfer:traceframe-info:read'. It has the id of the collected
954 trace state variables.
956 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
959 * New 'z' formatter for printing and examining memory, this displays the
960 value as hexadecimal zero padded on the left to the size of the type.
962 * GDB can now use Windows x64 unwinding data.
964 * The "set remotebaud" command has been replaced by "set serial baud".
965 Similarly, "show remotebaud" has been replaced by "show serial baud".
966 The "set remotebaud" and "show remotebaud" commands are still available
967 to provide backward compatibility with older versions of GDB.
969 *** Changes in GDB 7.6
971 * Target record has been renamed to record-full.
972 Record/replay is now enabled with the "record full" command.
973 This also affects settings that are associated with full record/replay
974 that have been moved from "set/show record" to "set/show record full":
976 set|show record full insn-number-max
977 set|show record full stop-at-limit
978 set|show record full memory-query
980 * A new record target "record-btrace" has been added. The new target
981 uses hardware support to record the control-flow of a process. It
982 does not support replaying the execution, but it implements the
983 below new commands for investigating the recorded execution log.
984 This new recording method can be enabled using:
988 The "record-btrace" target is only available on Intel Atom processors
989 and requires a Linux kernel 2.6.32 or later.
991 * Two new commands have been added for record/replay to give information
992 about the recorded execution without having to replay the execution.
993 The commands are only supported by "record btrace".
995 record instruction-history prints the execution history at
996 instruction granularity
998 record function-call-history prints the execution history at
1001 * New native configurations
1003 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1004 FreeBSD/powerpc powerpc*-*-freebsd
1005 x86_64/Cygwin x86_64-*-cygwin*
1006 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1010 ARM AArch64 aarch64*-*-elf
1011 ARM AArch64 GNU/Linux aarch64*-*-linux
1012 Lynx 178 PowerPC powerpc-*-lynx*178
1013 x86_64/Cygwin x86_64-*-cygwin*
1014 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1016 * If the configured location of system.gdbinit file (as given by the
1017 --with-system-gdbinit option at configure time) is in the
1018 data-directory (as specified by --with-gdb-datadir at configure
1019 time) or in one of its subdirectories, then GDB will look for the
1020 system-wide init file in the directory specified by the
1021 --data-directory command-line option.
1023 * New command line options:
1025 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1026 other initialization files, unlike -nx which disables all of them.
1028 * Removed command line options
1030 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1033 * The 'ptype' and 'whatis' commands now accept an argument to control
1036 * 'info proc' now works on some core files.
1040 ** Vectors can be created with gdb.Type.vector.
1042 ** Python's atexit.register now works in GDB.
1044 ** Types can be pretty-printed via a Python API.
1046 ** Python 3 is now supported (in addition to Python 2.4 or later)
1048 ** New class gdb.Architecture exposes GDB's internal representation
1049 of architecture in the Python API.
1051 ** New method Frame.architecture returns the gdb.Architecture object
1052 corresponding to the frame's architecture.
1054 * New Python-based convenience functions:
1056 ** $_memeq(buf1, buf2, length)
1057 ** $_streq(str1, str2)
1059 ** $_regex(str, regex)
1061 * The 'cd' command now defaults to using '~' (the home directory) if not
1064 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1065 default for GCC since November 2000.
1067 * The command 'forward-search' can now be abbreviated as 'fo'.
1069 * The command 'info tracepoints' can now display 'installed on target'
1070 or 'not installed on target' for each non-pending location of tracepoint.
1072 * New configure options
1074 --enable-libmcheck/--disable-libmcheck
1075 By default, development versions are built with -lmcheck on hosts
1076 that support it, in order to help track memory corruption issues.
1077 Release versions, on the other hand, are built without -lmcheck
1078 by default. The --enable-libmcheck/--disable-libmcheck configure
1079 options allow the user to override that default.
1080 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1081 This configure option allows the user to build GDB with
1082 libbabeltrace using which GDB can read Common Trace Format data.
1084 * New commands (for set/show, see "New options" below)
1087 Catch signals. This is similar to "handle", but allows commands and
1088 conditions to be attached.
1091 List the BFDs known to GDB.
1093 python-interactive [command]
1095 Start a Python interactive prompt, or evaluate the optional command
1096 and print the result of expressions.
1099 "py" is a new alias for "python".
1101 enable type-printer [name]...
1102 disable type-printer [name]...
1103 Enable or disable type printers.
1107 ** For the Renesas Super-H architecture, the "regs" command has been removed
1108 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1113 set print type methods (on|off)
1114 show print type methods
1115 Control whether method declarations are displayed by "ptype".
1116 The default is to show them.
1118 set print type typedefs (on|off)
1119 show print type typedefs
1120 Control whether typedef definitions are displayed by "ptype".
1121 The default is to show them.
1123 set filename-display basename|relative|absolute
1124 show filename-display
1125 Control the way in which filenames is displayed.
1126 The default is "relative", which preserves previous behavior.
1128 set trace-buffer-size
1129 show trace-buffer-size
1130 Request target to change the size of trace buffer.
1132 set remote trace-buffer-size-packet auto|on|off
1133 show remote trace-buffer-size-packet
1134 Control the use of the remote protocol `QTBuffer:size' packet.
1138 Control display of debugging messages related to ARM AArch64.
1141 set debug coff-pe-read
1142 show debug coff-pe-read
1143 Control display of debugging messages related to reading of COFF/PE
1148 Control display of debugging messages related to Mach-O symbols
1151 set debug notification
1152 show debug notification
1153 Control display of debugging info for async remote notification.
1157 ** Command parameter changes are now notified using new async record
1158 "=cmd-param-changed".
1159 ** Trace frame changes caused by command "tfind" are now notified using
1160 new async record "=traceframe-changed".
1161 ** The creation, deletion and modification of trace state variables
1162 are now notified using new async records "=tsv-created",
1163 "=tsv-deleted" and "=tsv-modified".
1164 ** The start and stop of process record are now notified using new
1165 async record "=record-started" and "=record-stopped".
1166 ** Memory changes are now notified using new async record
1168 ** The data-disassemble command response will include a "fullname" field
1169 containing the absolute file name when source has been requested.
1170 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1171 command, to allow pattern filling of memory areas.
1172 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1173 library load/unload events.
1174 ** The response to breakpoint commands and breakpoint async records
1175 includes an "installed" field containing a boolean state about each
1176 non-pending tracepoint location is whether installed on target or not.
1177 ** Output of the "-trace-status" command includes a "trace-file" field
1178 containing the name of the trace file being examined. This field is
1179 optional, and only present when examining a trace file.
1180 ** The "fullname" field is now always present along with the "file" field,
1181 even if the file cannot be found by GDB.
1183 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1184 You must have the LZMA library available when configuring GDB for this
1185 feature to be enabled. For more information, see:
1186 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1188 * New remote packets
1191 Set the size of trace buffer. The remote stub reports support for this
1192 packet to gdb's qSupported query.
1195 Enable Branch Trace Store (BTS)-based branch tracing for the current
1196 thread. The remote stub reports support for this packet to gdb's
1200 Disable branch tracing for the current thread. The remote stub reports
1201 support for this packet to gdb's qSupported query.
1204 Read the traced branches for the current thread. The remote stub
1205 reports support for this packet to gdb's qSupported query.
1207 *** Changes in GDB 7.5
1209 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1210 for more x32 ABI info.
1212 * GDB now supports access to MIPS DSP registers on Linux targets.
1214 * GDB now supports debugging microMIPS binaries.
1216 * The "info os" command on GNU/Linux can now display information on
1217 several new classes of objects managed by the operating system:
1218 "info os procgroups" lists process groups
1219 "info os files" lists file descriptors
1220 "info os sockets" lists internet-domain sockets
1221 "info os shm" lists shared-memory regions
1222 "info os semaphores" lists semaphores
1223 "info os msg" lists message queues
1224 "info os modules" lists loaded kernel modules
1226 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1227 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1228 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1229 options and inspect the probe arguments using the new $_probe_arg family
1230 of convenience variables. You can obtain more information about SystemTap
1231 in <http://sourceware.org/systemtap/>.
1233 * GDB now supports reversible debugging on ARM, it allows you to
1234 debug basic ARM and THUMB instructions, and provides
1235 record/replay support.
1237 * The option "symbol-reloading" has been deleted as it is no longer used.
1241 ** GDB commands implemented in Python can now be put in command class
1244 ** The "maint set python print-stack on|off" is now deleted.
1246 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1247 apply "flag enum"-style pretty-printing to any enum.
1249 ** gdb.lookup_symbol can now work when there is no current frame.
1251 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1252 the source at which the symbol was defined.
1254 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1255 method 'value'. The former indicates whether the symbol needs a
1256 frame in order to compute its value, and the latter computes the
1259 ** A new method 'referenced_value' on gdb.Value objects which can
1260 dereference pointer as well as C++ reference values.
1262 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1263 which return the global and static blocks (as gdb.Block objects),
1264 of the underlying symbol table, respectively.
1266 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1267 object associated with a PC value.
1269 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1270 of the address range occupied by code for the current source line.
1272 * Go language support.
1273 GDB now supports debugging programs written in the Go programming
1276 * GDBserver now supports stdio connections.
1277 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1279 * The binary "gdbtui" can no longer be built or installed.
1280 Use "gdb -tui" instead.
1282 * GDB will now print "flag" enums specially. A flag enum is one where
1283 all the enumerator values have no bits in common when pairwise
1284 "and"ed. When printing a value whose type is a flag enum, GDB will
1285 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1286 (gdb) print (enum E) 3
1289 * The filename part of a linespec will now match trailing components
1290 of a source file name. For example, "break gcc/expr.c:1000" will
1291 now set a breakpoint in build/gcc/expr.c, but not
1292 build/libcpp/expr.c.
1294 * The "info proc" and "generate-core-file" commands will now also
1295 work on remote targets connected to GDBserver on Linux.
1297 * The command "info catch" has been removed. It has been disabled
1298 since December 2007.
1300 * The "catch exception" and "catch assert" commands now accept
1301 a condition at the end of the command, much like the "break"
1302 command does. For instance:
1304 (gdb) catch exception Constraint_Error if Barrier = True
1306 Previously, it was possible to add a condition to such catchpoints,
1307 but it had to be done as a second step, after the catchpoint had been
1308 created, using the "condition" command.
1310 * The "info static-tracepoint-marker" command will now also work on
1311 native Linux targets with in-process agent.
1313 * GDB can now set breakpoints on inlined functions.
1315 * The .gdb_index section has been updated to include symbols for
1316 inlined functions. GDB will ignore older .gdb_index sections by
1317 default, which could cause symbol files to be loaded more slowly
1318 until their .gdb_index sections can be recreated. The new command
1319 "set use-deprecated-index-sections on" will cause GDB to use any older
1320 .gdb_index sections it finds. This will restore performance, but the
1321 ability to set breakpoints on inlined functions will be lost in symbol
1322 files with older .gdb_index sections.
1324 The .gdb_index section has also been updated to record more information
1325 about each symbol. This speeds up the "info variables", "info functions"
1326 and "info types" commands when used with programs having the .gdb_index
1327 section, as well as speeding up debugging with shared libraries using
1328 the .gdb_index section.
1330 * Ada support for GDB/MI Variable Objects has been added.
1332 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1337 ** New command -info-os is the MI equivalent of "info os".
1339 ** Output logs ("set logging" and related) now include MI output.
1343 ** "set use-deprecated-index-sections on|off"
1344 "show use-deprecated-index-sections on|off"
1345 Controls the use of deprecated .gdb_index sections.
1347 ** "catch load" and "catch unload" can be used to stop when a shared
1348 library is loaded or unloaded, respectively.
1350 ** "enable count" can be used to auto-disable a breakpoint after
1353 ** "info vtbl" can be used to show the virtual method tables for
1354 C++ and Java objects.
1356 ** "explore" and its sub commands "explore value" and "explore type"
1357 can be used to recursively explore values and types of
1358 expressions. These commands are available only if GDB is
1359 configured with '--with-python'.
1361 ** "info auto-load" shows status of all kinds of auto-loaded files,
1362 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1363 sequences of commands files, "info auto-load python-scripts"
1364 shows status of auto-loading Python script files,
1365 "info auto-load local-gdbinit" shows status of loading init file
1366 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1367 status of inferior specific thread debugging shared library loading.
1369 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1370 and "show auto-load-scripts" commands have been deprecated, use their
1371 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1372 and "show auto-load python-scripts" counterparts instead.
1374 ** "dprintf location,format,args..." creates a dynamic printf, which
1375 is basically a breakpoint that does a printf and immediately
1376 resumes your program's execution, so it is like a printf that you
1377 can insert dynamically at runtime instead of at compiletime.
1379 ** "set print symbol"
1381 Controls whether GDB attempts to display the symbol, if any,
1382 corresponding to addresses it prints. This defaults to "on", but
1383 you can set it to "off" to restore GDB's previous behavior.
1385 * Deprecated commands
1387 ** For the Renesas Super-H architecture, the "regs" command has been
1388 deprecated, and "info all-registers" should be used instead.
1392 Renesas RL78 rl78-*-elf
1393 HP OpenVMS ia64 ia64-hp-openvms*
1395 * GDBserver supports evaluation of breakpoint conditions. When
1396 support is advertised by GDBserver, GDB may be told to send the
1397 breakpoint conditions in bytecode form to GDBserver. GDBserver
1398 will only report the breakpoint trigger to GDB when its condition
1403 set mips compression
1404 show mips compression
1405 Select the compressed ISA encoding used in functions that have no symbol
1406 information available. The encoding can be set to either of:
1409 and is updated automatically from ELF file flags if available.
1411 set breakpoint condition-evaluation
1412 show breakpoint condition-evaluation
1413 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1414 GDBserver ("target"). Default option "auto" chooses the most efficient
1416 This option can improve debugger efficiency depending on the speed of the
1420 Disable auto-loading globally.
1423 Show auto-loading setting of all kinds of auto-loaded files.
1425 set auto-load gdb-scripts on|off
1426 show auto-load gdb-scripts
1427 Control auto-loading of GDB canned sequences of commands files.
1429 set auto-load python-scripts on|off
1430 show auto-load python-scripts
1431 Control auto-loading of Python script files.
1433 set auto-load local-gdbinit on|off
1434 show auto-load local-gdbinit
1435 Control loading of init file (.gdbinit) from current directory.
1437 set auto-load libthread-db on|off
1438 show auto-load libthread-db
1439 Control auto-loading of inferior specific thread debugging shared library.
1441 set auto-load scripts-directory <dir1>[:<dir2>...]
1442 show auto-load scripts-directory
1443 Set a list of directories from which to load auto-loaded scripts.
1444 Automatically loaded Python scripts and GDB scripts are located in one
1445 of the directories listed by this option.
1446 The delimiter (':' above) may differ according to the host platform.
1448 set auto-load safe-path <dir1>[:<dir2>...]
1449 show auto-load safe-path
1450 Set a list of directories from which it is safe to auto-load files.
1451 The delimiter (':' above) may differ according to the host platform.
1453 set debug auto-load on|off
1454 show debug auto-load
1455 Control display of debugging info for auto-loading the files above.
1457 set dprintf-style gdb|call|agent
1459 Control the way in which a dynamic printf is performed; "gdb"
1460 requests a GDB printf command, while "call" causes dprintf to call a
1461 function in the inferior. "agent" requests that the target agent
1462 (such as GDBserver) do the printing.
1464 set dprintf-function <expr>
1465 show dprintf-function
1466 set dprintf-channel <expr>
1467 show dprintf-channel
1468 Set the function and optional first argument to the call when using
1469 the "call" style of dynamic printf.
1471 set disconnected-dprintf on|off
1472 show disconnected-dprintf
1473 Control whether agent-style dynamic printfs continue to be in effect
1474 after GDB disconnects.
1476 * New configure options
1478 --with-auto-load-dir
1479 Configure default value for the 'set auto-load scripts-directory'
1480 setting above. It defaults to '$debugdir:$datadir/auto-load',
1481 $debugdir representing global debugging info directories (available
1482 via 'show debug-file-directory') and $datadir representing GDB's data
1483 directory (available via 'show data-directory').
1485 --with-auto-load-safe-path
1486 Configure default value for the 'set auto-load safe-path' setting
1487 above. It defaults to the --with-auto-load-dir setting.
1489 --without-auto-load-safe-path
1490 Set 'set auto-load safe-path' to '/', effectively disabling this
1493 * New remote packets
1495 z0/z1 conditional breakpoints extension
1497 The z0/z1 breakpoint insertion packets have been extended to carry
1498 a list of conditional expressions over to the remote stub depending on the
1499 condition evaluation mode. The use of this extension can be controlled
1500 via the "set remote conditional-breakpoints-packet" command.
1504 Specify the signals which the remote stub may pass to the debugged
1505 program without GDB involvement.
1507 * New command line options
1509 --init-command=FILE, -ix Like --command, -x but execute it
1510 before loading inferior.
1511 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1512 execute it before loading inferior.
1514 *** Changes in GDB 7.4
1516 * GDB now handles ambiguous linespecs more consistently; the existing
1517 FILE:LINE support has been expanded to other types of linespecs. A
1518 breakpoint will now be set on all matching locations in all
1519 inferiors, and locations will be added or removed according to
1522 * GDB now allows you to skip uninteresting functions and files when
1523 stepping with the "skip function" and "skip file" commands.
1525 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1526 and "show remote hardware-watchpoint-length-limit". These allows to
1527 set or show the maximum length limit (in bytes) of a remote
1528 target hardware watchpoint.
1530 This allows e.g. to use "unlimited" hardware watchpoints with the
1531 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1532 watchpoints are slower than real hardware watchpoints but are
1533 significantly faster than gdb software watchpoints.
1537 ** The register_pretty_printer function in module gdb.printing now takes
1538 an optional `replace' argument. If True, the new printer replaces any
1541 ** The "maint set python print-stack on|off" command has been
1542 deprecated and will be deleted in GDB 7.5.
1543 A new command: "set python print-stack none|full|message" has
1544 replaced it. Additionally, the default for "print-stack" is
1545 now "message", which just prints the error message without
1548 ** A prompt substitution hook (prompt_hook) is now available to the
1551 ** A new Python module, gdb.prompt has been added to the GDB Python
1552 modules library. This module provides functionality for
1553 escape sequences in prompts (used by set/show
1554 extended-prompt). These escape sequences are replaced by their
1555 corresponding value.
1557 ** Python commands and convenience-functions located in
1558 'data-directory'/python/gdb/command and
1559 'data-directory'/python/gdb/function are now automatically loaded
1562 ** Blocks now provide four new attributes. global_block and
1563 static_block will return the global and static blocks
1564 respectively. is_static and is_global are boolean attributes
1565 that indicate if the block is one of those two types.
1567 ** Symbols now provide the "type" attribute, the type of the symbol.
1569 ** The "gdb.breakpoint" function has been deprecated in favor of
1572 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1573 of a function. This class is based on the "finish" command
1574 available in the CLI.
1576 ** Type objects for struct and union types now allow access to
1577 the fields using standard Python dictionary (mapping) methods.
1578 For example, "some_type['myfield']" now works, as does
1579 "some_type.items()".
1581 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1584 ** A new function, "deep_items" has been added to the gdb.types
1585 module in the GDB Python modules library. This function returns
1586 an iterator over the fields of a struct or union type. Unlike
1587 the standard Python "iteritems" method, it will recursively traverse
1588 any anonymous fields.
1592 ** "*stopped" events can report several new "reason"s, such as
1595 ** Breakpoint changes are now notified using new async records, like
1596 "=breakpoint-modified".
1598 ** New command -ada-task-info.
1600 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1601 $sdir specifies the default system locations of shared libraries.
1602 $pdir specifies the directory where the libpthread used by the application
1605 GDB no longer looks in $sdir and $pdir after it has searched the directories
1606 mentioned in libthread-db-search-path. If you want to search those
1607 directories, they must be specified in libthread-db-search-path.
1608 The default value of libthread-db-search-path on GNU/Linux and Solaris
1609 systems is now "$sdir:$pdir".
1611 $pdir is not supported by gdbserver, it is currently ignored.
1612 $sdir is supported by gdbserver.
1614 * New configure option --with-iconv-bin.
1615 When using the internationalization support like the one in the GNU C
1616 library, GDB will invoke the "iconv" program to get a list of supported
1617 character sets. If this program lives in a non-standard location, one can
1618 use this option to specify where to find it.
1620 * When natively debugging programs on PowerPC BookE processors running
1621 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1622 watchpoints, which specify a mask in addition to an address to watch.
1623 The mask specifies that some bits of an address (the bits which are
1624 reset in the mask) should be ignored when matching the address accessed
1625 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1626 section in the user manual for more details.
1628 * The new option --once causes GDBserver to stop listening for connections once
1629 the first connection is made. The listening port used by GDBserver will
1630 become available after that.
1632 * New commands "info macros" and "alias" have been added.
1634 * New function parameters suffix @entry specifies value of function parameter
1635 at the time the function got called. Entry values are available only since
1641 "!" is now an alias of the "shell" command.
1642 Note that no space is needed between "!" and SHELL COMMAND.
1646 watch EXPRESSION mask MASK_VALUE
1647 The watch command now supports the mask argument which allows creation
1648 of masked watchpoints, if the current architecture supports this feature.
1650 info auto-load-scripts [REGEXP]
1651 This command was formerly named "maintenance print section-scripts".
1652 It is now generally useful and is no longer a maintenance-only command.
1654 info macro [-all] [--] MACRO
1655 The info macro command has new options `-all' and `--'. The first for
1656 printing all definitions of a macro. The second for explicitly specifying
1657 the end of arguments and the beginning of the macro name in case the macro
1658 name starts with a hyphen.
1660 collect[/s] EXPRESSIONS
1661 The tracepoint collect command now takes an optional modifier "/s"
1662 that directs it to dereference pointer-to-character types and
1663 collect the bytes of memory up to a zero byte. The behavior is
1664 similar to what you see when you use the regular print command on a
1665 string. An optional integer following the "/s" sets a bound on the
1666 number of bytes that will be collected.
1669 The trace start command now interprets any supplied arguments as a
1670 note to be recorded with the trace run, with an effect similar to
1671 setting the variable trace-notes.
1674 The trace stop command now interprets any arguments as a note to be
1675 mentioned along with the tstatus report that the trace was stopped
1676 with a command. The effect is similar to setting the variable
1679 * Tracepoints can now be enabled and disabled at any time after a trace
1680 experiment has been started using the standard "enable" and "disable"
1681 commands. It is now possible to start a trace experiment with no enabled
1682 tracepoints; GDB will display a warning, but will allow the experiment to
1683 begin, assuming that tracepoints will be enabled as needed while the trace
1686 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1687 locations with 4-byte instructions, when they were previously
1688 limited to locations with instructions of 5 bytes or longer.
1692 set debug dwarf2-read
1693 show debug dwarf2-read
1694 Turns on or off display of debugging messages related to reading
1695 DWARF debug info. The default is off.
1697 set debug symtab-create
1698 show debug symtab-create
1699 Turns on or off display of debugging messages related to symbol table
1700 creation. The default is off.
1703 show extended-prompt
1704 Set the GDB prompt, and allow escape sequences to be inserted to
1705 display miscellaneous information (see 'help set extended-prompt'
1706 for the list of sequences). This prompt (and any information
1707 accessed through the escape sequences) is updated every time the
1708 prompt is displayed.
1710 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1711 show print entry-values
1712 Set printing of frame argument values at function entry. In some cases
1713 GDB can determine the value of function argument which was passed by the
1714 function caller, even if the value was modified inside the called function.
1716 set debug entry-values
1717 show debug entry-values
1718 Control display of debugging info for determining frame argument values at
1719 function entry and virtual tail call frames.
1721 set basenames-may-differ
1722 show basenames-may-differ
1723 Set whether a source file may have multiple base names.
1724 (A "base name" is the name of a file with the directory part removed.
1725 Example: The base name of "/home/user/hello.c" is "hello.c".)
1726 If set, GDB will canonicalize file names (e.g., expand symlinks)
1727 before comparing them. Canonicalization is an expensive operation,
1728 but it allows the same file be known by more than one base name.
1729 If not set (the default), all source files are assumed to have just
1730 one base name, and gdb will do file name comparisons more efficiently.
1736 Set a user name and notes for the current and any future trace runs.
1737 This is useful for long-running and/or disconnected traces, to
1738 inform others (or yourself) as to who is running the trace, supply
1739 contact information, or otherwise explain what is going on.
1741 set trace-stop-notes
1742 show trace-stop-notes
1743 Set a note attached to the trace run, that is displayed when the
1744 trace has been stopped by a tstop command. This is useful for
1745 instance as an explanation, if you are stopping a trace run that was
1746 started by someone else.
1748 * New remote packets
1752 Dynamically enable a tracepoint in a started trace experiment.
1756 Dynamically disable a tracepoint in a started trace experiment.
1760 Set the user and notes of the trace run.
1764 Query the current status of a tracepoint.
1768 Query the minimum length of instruction at which a fast tracepoint may
1771 * Dcache size (number of lines) and line-size are now runtime-configurable
1772 via "set dcache line" and "set dcache line-size" commands.
1776 Texas Instruments TMS320C6x tic6x-*-*
1780 Renesas RL78 rl78-*-elf
1782 *** Changes in GDB 7.3.1
1784 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1786 *** Changes in GDB 7.3
1788 * GDB has a new command: "thread find [REGEXP]".
1789 It finds the thread id whose name, target id, or thread extra info
1790 matches the given regular expression.
1792 * The "catch syscall" command now works on mips*-linux* targets.
1794 * The -data-disassemble MI command now supports modes 2 and 3 for
1795 dumping the instruction opcodes.
1797 * New command line options
1799 -data-directory DIR Specify DIR as the "data-directory".
1800 This is mostly for testing purposes.
1802 * The "maint set python auto-load on|off" command has been renamed to
1803 "set auto-load-scripts on|off".
1805 * GDB has a new command: "set directories".
1806 It is like the "dir" command except that it replaces the
1807 source path list instead of augmenting it.
1809 * GDB now understands thread names.
1811 On GNU/Linux, "info threads" will display the thread name as set by
1812 prctl or pthread_setname_np.
1814 There is also a new command, "thread name", which can be used to
1815 assign a name internally for GDB to display.
1818 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1819 has been integrated into GDB.
1823 ** The function gdb.Write now accepts an optional keyword 'stream'.
1824 This keyword, when provided, will direct the output to either
1825 stdout, stderr, or GDB's logging output.
1827 ** Parameters can now be be sub-classed in Python, and in particular
1828 you may implement the get_set_doc and get_show_doc functions.
1829 This improves how Parameter set/show documentation is processed
1830 and allows for more dynamic content.
1832 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1833 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1834 have an is_valid method.
1836 ** Breakpoints can now be sub-classed in Python, and in particular
1837 you may implement a 'stop' function that is executed each time
1838 the inferior reaches that breakpoint.
1840 ** New function gdb.lookup_global_symbol looks up a global symbol.
1842 ** GDB values in Python are now callable if the value represents a
1843 function. For example, if 'some_value' represents a function that
1844 takes two integer parameters and returns a value, you can call
1845 that function like so:
1847 result = some_value (10,20)
1849 ** Module gdb.types has been added.
1850 It contains a collection of utilities for working with gdb.Types objects:
1851 get_basic_type, has_field, make_enum_dict.
1853 ** Module gdb.printing has been added.
1854 It contains utilities for writing and registering pretty-printers.
1855 New classes: PrettyPrinter, SubPrettyPrinter,
1856 RegexpCollectionPrettyPrinter.
1857 New function: register_pretty_printer.
1859 ** New commands "info pretty-printers", "enable pretty-printer" and
1860 "disable pretty-printer" have been added.
1862 ** gdb.parameter("directories") is now available.
1864 ** New function gdb.newest_frame returns the newest frame in the
1867 ** The gdb.InferiorThread class has a new "name" attribute. This
1868 holds the thread's name.
1870 ** Python Support for Inferior events.
1871 Python scripts can add observers to be notified of events
1872 occurring in the process being debugged.
1873 The following events are currently supported:
1874 - gdb.events.cont Continue event.
1875 - gdb.events.exited Inferior exited event.
1876 - gdb.events.stop Signal received, and Breakpoint hit events.
1880 ** GDB now puts template parameters in scope when debugging in an
1881 instantiation. For example, if you have:
1883 template<int X> int func (void) { return X; }
1885 then if you step into func<5>, "print X" will show "5". This
1886 feature requires proper debuginfo support from the compiler; it
1887 was added to GCC 4.5.
1889 ** The motion commands "next", "finish", "until", and "advance" now
1890 work better when exceptions are thrown. In particular, GDB will
1891 no longer lose control of the inferior; instead, the GDB will
1892 stop the inferior at the point at which the exception is caught.
1893 This functionality requires a change in the exception handling
1894 code that was introduced in GCC 4.5.
1896 * GDB now follows GCC's rules on accessing volatile objects when
1897 reading or writing target state during expression evaluation.
1898 One notable difference to prior behavior is that "print x = 0"
1899 no longer generates a read of x; the value of the assignment is
1900 now always taken directly from the value being assigned.
1902 * GDB now has some support for using labels in the program's source in
1903 linespecs. For instance, you can use "advance label" to continue
1904 execution to a label.
1906 * GDB now has support for reading and writing a new .gdb_index
1907 section. This section holds a fast index of DWARF debugging
1908 information and can be used to greatly speed up GDB startup and
1909 operation. See the documentation for `save gdb-index' for details.
1911 * The "watch" command now accepts an optional "-location" argument.
1912 When used, this causes GDB to watch the memory referred to by the
1913 expression. Such a watchpoint is never deleted due to it going out
1916 * GDB now supports thread debugging of core dumps on GNU/Linux.
1918 GDB now activates thread debugging using the libthread_db library
1919 when debugging GNU/Linux core dumps, similarly to when debugging
1920 live processes. As a result, when debugging a core dump file, GDB
1921 is now able to display pthread_t ids of threads. For example, "info
1922 threads" shows the same output as when debugging the process when it
1923 was live. In earlier releases, you'd see something like this:
1926 * 1 LWP 6780 main () at main.c:10
1928 While now you see this:
1931 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1933 It is also now possible to inspect TLS variables when debugging core
1936 When debugging a core dump generated on a machine other than the one
1937 used to run GDB, you may need to point GDB at the correct
1938 libthread_db library with the "set libthread-db-search-path"
1939 command. See the user manual for more details on this command.
1941 * When natively debugging programs on PowerPC BookE processors running
1942 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1943 which stop execution of the inferior whenever it executes an instruction
1944 at any address within the specified range. See the "PowerPC Embedded"
1945 section in the user manual for more details.
1947 * New features in the GDB remote stub, GDBserver
1949 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1950 and i686 LynxOS (version 5.x).
1952 ** GDBserver is now supported on Blackfin Linux.
1954 * New native configurations
1956 ia64 HP-UX ia64-*-hpux*
1960 Analog Devices, Inc. Blackfin Processor bfin-*
1962 * Ada task switching is now supported on sparc-elf targets when
1963 debugging a program using the Ravenscar Profile. For more information,
1964 see the "Tasking Support when using the Ravenscar Profile" section
1965 in the GDB user manual.
1967 * Guile support was removed.
1969 * New features in the GNU simulator
1971 ** The --map-info flag lists all known core mappings.
1973 ** CFI flashes may be simulated via the "cfi" device.
1975 *** Changes in GDB 7.2
1977 * Shared library support for remote targets by default
1979 When GDB is configured for a generic, non-OS specific target, like
1980 for example, --target=arm-eabi or one of the many *-*-elf targets,
1981 GDB now queries remote stubs for loaded shared libraries using the
1982 `qXfer:libraries:read' packet. Previously, shared library support
1983 was always disabled for such configurations.
1987 ** Argument Dependent Lookup (ADL)
1989 In C++ ADL lookup directs function search to the namespaces of its
1990 arguments even if the namespace has not been imported.
2000 Here the compiler will search for `foo' in the namespace of 'b'
2001 and find A::foo. GDB now supports this. This construct is commonly
2002 used in the Standard Template Library for operators.
2004 ** Improved User Defined Operator Support
2006 In addition to member operators, GDB now supports lookup of operators
2007 defined in a namespace and imported with a `using' directive, operators
2008 defined in the global scope, operators imported implicitly from an
2009 anonymous namespace, and the ADL operators mentioned in the previous
2011 GDB now also supports proper overload resolution for all the previously
2012 mentioned flavors of operators.
2014 ** static const class members
2016 Printing of static const class members that are initialized in the
2017 class definition has been fixed.
2019 * Windows Thread Information Block access.
2021 On Windows targets, GDB now supports displaying the Windows Thread
2022 Information Block (TIB) structure. This structure is visible either
2023 by using the new command `info w32 thread-information-block' or, by
2024 dereferencing the new convenience variable named `$_tlb', a
2025 thread-specific pointer to the TIB. This feature is also supported
2026 when remote debugging using GDBserver.
2028 * Static tracepoints
2030 Static tracepoints are calls in the user program into a tracing
2031 library. One such library is a port of the LTTng kernel tracer to
2032 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2033 When debugging with GDBserver, GDB now supports combining the GDB
2034 tracepoint machinery with such libraries. For example: the user can
2035 use GDB to probe a static tracepoint marker (a call from the user
2036 program into the tracing library) with the new "strace" command (see
2037 "New commands" below). This creates a "static tracepoint" in the
2038 breakpoint list, that can be manipulated with the same feature set
2039 as fast and regular tracepoints. E.g., collect registers, local and
2040 global variables, collect trace state variables, and define
2041 tracepoint conditions. In addition, the user can collect extra
2042 static tracepoint marker specific data, by collecting the new
2043 $_sdata internal variable. When analyzing the trace buffer, you can
2044 inspect $_sdata like any other variable available to GDB. For more
2045 information, see the "Tracepoints" chapter in GDB user manual. New
2046 remote packets have been defined to support static tracepoints, see
2047 the "New remote packets" section below.
2049 * Better reconstruction of tracepoints after disconnected tracing
2051 GDB will attempt to download the original source form of tracepoint
2052 definitions when starting a trace run, and then will upload these
2053 upon reconnection to the target, resulting in a more accurate
2054 reconstruction of the tracepoints that are in use on the target.
2058 You can now exercise direct control over the ways that GDB can
2059 affect your program. For instance, you can disallow the setting of
2060 breakpoints, so that the program can run continuously (assuming
2061 non-stop mode). In addition, the "observer" variable is available
2062 to switch all of the different controls; in observer mode, GDB
2063 cannot affect the target's behavior at all, which is useful for
2064 tasks like diagnosing live systems in the field.
2066 * The new convenience variable $_thread holds the number of the
2069 * New remote packets
2073 Return the address of the Windows Thread Information Block of a given thread.
2077 In response to several of the tracepoint packets, the target may now
2078 also respond with a number of intermediate `qRelocInsn' request
2079 packets before the final result packet, to have GDB handle
2080 relocating an instruction to execute at a different address. This
2081 is particularly useful for stubs that support fast tracepoints. GDB
2082 reports support for this feature in the qSupported packet.
2086 List static tracepoint markers in the target program.
2090 List static tracepoint markers at a given address in the target
2093 qXfer:statictrace:read
2095 Read the static trace data collected (by a `collect $_sdata'
2096 tracepoint action). The remote stub reports support for this packet
2097 to gdb's qSupported query.
2101 Send the current settings of GDB's permission flags.
2105 Send part of the source (textual) form of a tracepoint definition,
2106 which includes location, conditional, and action list.
2108 * The source command now accepts a -s option to force searching for the
2109 script in the source search path even if the script name specifies
2112 * New features in the GDB remote stub, GDBserver
2114 - GDBserver now support tracepoints (including fast tracepoints, and
2115 static tracepoints). The feature is currently supported by the
2116 i386-linux and amd64-linux builds. See the "Tracepoints support
2117 in gdbserver" section in the manual for more information.
2119 GDBserver JIT compiles the tracepoint's conditional agent
2120 expression bytecode into native code whenever possible for low
2121 overhead dynamic tracepoints conditionals. For such tracepoints,
2122 an expression that examines program state is evaluated when the
2123 tracepoint is reached, in order to determine whether to capture
2124 trace data. If the condition is simple and false, processing the
2125 tracepoint finishes very quickly and no data is gathered.
2127 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2128 for static tracepoints support.
2130 - GDBserver now supports x86_64 Windows 64-bit debugging.
2132 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2133 it understands register description.
2135 * The --batch flag now disables pagination and queries.
2137 * X86 general purpose registers
2139 GDB now supports reading/writing byte, word and double-word x86
2140 general purpose registers directly. This means you can use, say,
2141 $ah or $ax to refer, respectively, to the byte register AH and
2142 16-bit word register AX that are actually portions of the 32-bit
2143 register EAX or 64-bit register RAX.
2145 * The `commands' command now accepts a range of breakpoints to modify.
2146 A plain `commands' following a command that creates multiple
2147 breakpoints affects all the breakpoints set by that command. This
2148 applies to breakpoints set by `rbreak', and also applies when a
2149 single `break' command creates multiple breakpoints (e.g.,
2150 breakpoints on overloaded c++ functions).
2152 * The `rbreak' command now accepts a filename specification as part of
2153 its argument, limiting the functions selected by the regex to those
2154 in the specified file.
2156 * Support for remote debugging Windows and SymbianOS shared libraries
2157 from Unix hosts has been improved. Non Windows GDB builds now can
2158 understand target reported file names that follow MS-DOS based file
2159 system semantics, such as file names that include drive letters and
2160 use the backslash character as directory separator. This makes it
2161 possible to transparently use the "set sysroot" and "set
2162 solib-search-path" on Unix hosts to point as host copies of the
2163 target's shared libraries. See the new command "set
2164 target-file-system-kind" described below, and the "Commands to
2165 specify files" section in the user manual for more information.
2169 eval template, expressions...
2170 Convert the values of one or more expressions under the control
2171 of the string template to a command line, and call it.
2173 set target-file-system-kind unix|dos-based|auto
2174 show target-file-system-kind
2175 Set or show the assumed file system kind for target reported file
2178 save breakpoints <filename>
2179 Save all current breakpoint definitions to a file suitable for use
2180 in a later debugging session. To read the saved breakpoint
2181 definitions, use the `source' command.
2183 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2186 info static-tracepoint-markers
2187 Display information about static tracepoint markers in the target.
2189 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2190 Define a static tracepoint by probing a marker at the given
2191 function, line, address, or marker ID.
2195 Enable and disable observer mode.
2197 set may-write-registers on|off
2198 set may-write-memory on|off
2199 set may-insert-breakpoints on|off
2200 set may-insert-tracepoints on|off
2201 set may-insert-fast-tracepoints on|off
2202 set may-interrupt on|off
2203 Set individual permissions for GDB effects on the target. Note that
2204 some of these settings can have undesirable or surprising
2205 consequences, particularly when changed in the middle of a session.
2206 For instance, disabling the writing of memory can prevent
2207 breakpoints from being inserted, cause single-stepping to fail, or
2208 even crash your program, if you disable after breakpoints have been
2209 inserted. However, GDB should not crash.
2211 set record memory-query on|off
2212 show record memory-query
2213 Control whether to stop the inferior if memory changes caused
2214 by an instruction cannot be recorded.
2219 The disassemble command now supports "start,+length" form of two arguments.
2223 ** GDB now provides a new directory location, called the python directory,
2224 where Python scripts written for GDB can be installed. The location
2225 of that directory is <data-directory>/python, where <data-directory>
2226 is the GDB data directory. For more details, see section `Scripting
2227 GDB using Python' in the manual.
2229 ** The GDB Python API now has access to breakpoints, symbols, symbol
2230 tables, program spaces, inferiors, threads and frame's code blocks.
2231 Additionally, GDB Parameters can now be created from the API, and
2232 manipulated via set/show in the CLI.
2234 ** New functions gdb.target_charset, gdb.target_wide_charset,
2235 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2237 ** New exception gdb.GdbError.
2239 ** Pretty-printers are now also looked up in the current program space.
2241 ** Pretty-printers can now be individually enabled and disabled.
2243 ** GDB now looks for names of Python scripts to auto-load in a
2244 special section named `.debug_gdb_scripts', in addition to looking
2245 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2247 * Tracepoint actions were unified with breakpoint commands. In particular,
2248 there are no longer differences in "info break" output for breakpoints and
2249 tracepoints and the "commands" command can be used for both tracepoints and
2250 regular breakpoints.
2254 ARM Symbian arm*-*-symbianelf*
2256 * D language support.
2257 GDB now supports debugging programs written in the D programming
2260 * GDB now supports the extended ptrace interface for PowerPC which is
2261 available since Linux kernel version 2.6.34. This automatically enables
2262 any hardware breakpoints and additional hardware watchpoints available in
2263 the processor. The old ptrace interface exposes just one hardware
2264 watchpoint and no hardware breakpoints.
2266 * GDB is now able to use the Data Value Compare (DVC) register available on
2267 embedded PowerPC processors to implement in hardware simple watchpoint
2268 conditions of the form:
2270 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2272 This works in native GDB running on Linux kernels with the extended ptrace
2273 interface mentioned above.
2275 *** Changes in GDB 7.1
2279 ** Namespace Support
2281 GDB now supports importing of namespaces in C++. This enables the
2282 user to inspect variables from imported namespaces. Support for
2283 namepace aliasing has also been added. So, if a namespace is
2284 aliased in the current scope (e.g. namepace C=A; ) the user can
2285 print variables using the alias (e.g. (gdb) print C::x).
2289 All known bugs relating to the printing of virtual base class were
2290 fixed. It is now possible to call overloaded static methods using a
2295 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2296 and reinterpret_cast<> are now handled by the C++ expression parser.
2300 Xilinx MicroBlaze microblaze-*-*
2305 Xilinx MicroBlaze microblaze
2308 * Multi-program debugging.
2310 GDB now has support for multi-program (a.k.a. multi-executable or
2311 multi-exec) debugging. This allows for debugging multiple inferiors
2312 simultaneously each running a different program under the same GDB
2313 session. See "Debugging Multiple Inferiors and Programs" in the
2314 manual for more information. This implied some user visible changes
2315 in the multi-inferior support. For example, "info inferiors" now
2316 lists inferiors that are not running yet or that have exited
2317 already. See also "New commands" and "New options" below.
2319 * New tracing features
2321 GDB's tracepoint facility now includes several new features:
2323 ** Trace state variables
2325 GDB tracepoints now include support for trace state variables, which
2326 are variables managed by the target agent during a tracing
2327 experiment. They are useful for tracepoints that trigger each
2328 other, so for instance one tracepoint can count hits in a variable,
2329 and then a second tracepoint has a condition that is true when the
2330 count reaches a particular value. Trace state variables share the
2331 $-syntax of GDB convenience variables, and can appear in both
2332 tracepoint actions and condition expressions. Use the "tvariable"
2333 command to create, and "info tvariables" to view; see "Trace State
2334 Variables" in the manual for more detail.
2338 GDB now includes an option for defining fast tracepoints, which
2339 targets may implement more efficiently, such as by installing a jump
2340 into the target agent rather than a trap instruction. The resulting
2341 speedup can be by two orders of magnitude or more, although the
2342 tradeoff is that some program locations on some target architectures
2343 might not allow fast tracepoint installation, for instance if the
2344 instruction to be replaced is shorter than the jump. To request a
2345 fast tracepoint, use the "ftrace" command, with syntax identical to
2346 the regular trace command.
2348 ** Disconnected tracing
2350 It is now possible to detach GDB from the target while it is running
2351 a trace experiment, then reconnect later to see how the experiment
2352 is going. In addition, a new variable disconnected-tracing lets you
2353 tell the target agent whether to continue running a trace if the
2354 connection is lost unexpectedly.
2358 GDB now has the ability to save the trace buffer into a file, and
2359 then use that file as a target, similarly to you can do with
2360 corefiles. You can select trace frames, print data that was
2361 collected in them, and use tstatus to display the state of the
2362 tracing run at the moment that it was saved. To create a trace
2363 file, use "tsave <filename>", and to use it, do "target tfile
2366 ** Circular trace buffer
2368 You can ask the target agent to handle the trace buffer as a
2369 circular buffer, discarding the oldest trace frames to make room for
2370 newer ones, by setting circular-trace-buffer to on. This feature may
2371 not be available for all target agents.
2376 The disassemble command, when invoked with two arguments, now requires
2377 the arguments to be comma-separated.
2380 The info variables command now displays variable definitions. Files
2381 which only declare a variable are not shown.
2384 The source command is now capable of sourcing Python scripts.
2385 This feature is dependent on the debugger being build with Python
2388 Related to this enhancement is also the introduction of a new command
2389 "set script-extension" (see below).
2391 * New commands (for set/show, see "New options" below)
2393 record save [<FILENAME>]
2394 Save a file (in core file format) containing the process record
2395 execution log for replay debugging at a later time.
2397 record restore <FILENAME>
2398 Restore the process record execution log that was saved at an
2399 earlier time, for replay debugging.
2401 add-inferior [-copies <N>] [-exec <FILENAME>]
2404 clone-inferior [-copies <N>] [ID]
2405 Make a new inferior ready to execute the same program another
2406 inferior has loaded.
2411 maint info program-spaces
2412 List the program spaces loaded into GDB.
2414 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2415 show remote interrupt-sequence
2416 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2417 as the sequence to the remote target in order to interrupt the execution.
2418 Ctrl-C is a default. Some system prefers BREAK which is high level of
2419 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2420 Magic SysRq g. It is BREAK signal and character 'g'.
2422 set remote interrupt-on-connect [on | off]
2423 show remote interrupt-on-connect
2424 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2425 remote target when gdb connects to it. This is needed when you debug
2428 set remotebreak [on | off]
2430 Deprecated. Use "set/show remote interrupt-sequence" instead.
2432 tvariable $NAME [ = EXP ]
2433 Create or modify a trace state variable.
2436 List trace state variables and their values.
2438 delete tvariable $NAME ...
2439 Delete one or more trace state variables.
2442 Evaluate the given expressions without collecting anything into the
2443 trace buffer. (Valid in tracepoint actions only.)
2445 ftrace FN / FILE:LINE / *ADDR
2446 Define a fast tracepoint at the given function, line, or address.
2448 * New expression syntax
2450 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2451 GDB now parses 0b101010 identically with 42.
2455 set follow-exec-mode new|same
2456 show follow-exec-mode
2457 Control whether GDB reuses the same inferior across an exec call or
2458 creates a new one. This is useful to be able to restart the old
2459 executable after the inferior having done an exec call.
2461 set default-collect EXPR, ...
2462 show default-collect
2463 Define a list of expressions to be collected at each tracepoint.
2464 This is a useful way to ensure essential items are not overlooked,
2465 such as registers or a critical global variable.
2467 set disconnected-tracing
2468 show disconnected-tracing
2469 If set to 1, the target is instructed to continue tracing if it
2470 loses its connection to GDB. If 0, the target is to stop tracing
2473 set circular-trace-buffer
2474 show circular-trace-buffer
2475 If set to on, the target is instructed to use a circular trace buffer
2476 and discard the oldest trace frames instead of stopping the trace due
2477 to a full trace buffer. If set to off, the trace stops when the buffer
2478 fills up. Some targets may not support this.
2480 set script-extension off|soft|strict
2481 show script-extension
2482 If set to "off", the debugger does not perform any script language
2483 recognition, and all sourced files are assumed to be GDB scripts.
2484 If set to "soft" (the default), files are sourced according to
2485 filename extension, falling back to GDB scripts if the first
2487 If set to "strict", files are sourced according to filename extension.
2489 set ada trust-PAD-over-XVS on|off
2490 show ada trust-PAD-over-XVS
2491 If off, activate a workaround against a bug in the debugging information
2492 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2493 the GCC sources for more information about the GNAT encoding and
2494 PAD types in particular). It is always safe to set this option to
2495 off, but this introduces a slight performance penalty. The default
2498 * Python API Improvements
2500 ** GDB provides the new class gdb.LazyString. This is useful in
2501 some pretty-printing cases. The new method gdb.Value.lazy_string
2502 provides a simple way to create objects of this type.
2504 ** The fields returned by gdb.Type.fields now have an
2505 `is_base_class' attribute.
2507 ** The new method gdb.Type.range returns the range of an array type.
2509 ** The new method gdb.parse_and_eval can be used to parse and
2510 evaluate an expression.
2512 * New remote packets
2515 Define a trace state variable.
2518 Get the current value of a trace state variable.
2521 Set desired tracing behavior upon disconnection.
2524 Set the trace buffer to be linear or circular.
2527 Get data about the tracepoints currently in use.
2531 Process record now works correctly with hardware watchpoints.
2533 Multiple bug fixes have been made to the mips-irix port, making it
2534 much more reliable. In particular:
2535 - Debugging threaded applications is now possible again. Previously,
2536 GDB would hang while starting the program, or while waiting for
2537 the program to stop at a breakpoint.
2538 - Attaching to a running process no longer hangs.
2539 - An error occurring while loading a core file has been fixed.
2540 - Changing the value of the PC register now works again. This fixes
2541 problems observed when using the "jump" command, or when calling
2542 a function from GDB, or even when assigning a new value to $pc.
2543 - With the "finish" and "return" commands, the return value for functions
2544 returning a small array is now correctly printed.
2545 - It is now possible to break on shared library code which gets executed
2546 during a shared library init phase (code executed while executing
2547 their .init section). Previously, the breakpoint would have no effect.
2548 - GDB is now able to backtrace through the signal handler for
2549 non-threaded programs.
2551 PIE (Position Independent Executable) programs debugging is now supported.
2552 This includes debugging execution of PIC (Position Independent Code) shared
2553 libraries although for that, it should be possible to run such libraries as an
2556 *** Changes in GDB 7.0
2558 * GDB now has an interface for JIT compilation. Applications that
2559 dynamically generate code can create symbol files in memory and register
2560 them with GDB. For users, the feature should work transparently, and
2561 for JIT developers, the interface is documented in the GDB manual in the
2562 "JIT Compilation Interface" chapter.
2564 * Tracepoints may now be conditional. The syntax is as for
2565 breakpoints; either an "if" clause appended to the "trace" command,
2566 or the "condition" command is available. GDB sends the condition to
2567 the target for evaluation using the same bytecode format as is used
2568 for tracepoint actions.
2570 * The disassemble command now supports: an optional /r modifier, print the
2571 raw instructions in hex as well as in symbolic form, and an optional /m
2572 modifier to print mixed source+assembly.
2574 * Process record and replay
2576 In a architecture environment that supports ``process record and
2577 replay'', ``process record and replay'' target can record a log of
2578 the process execution, and replay it with both forward and reverse
2581 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2582 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2583 set execution-direction {forward|reverse}, for targets that support
2586 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2587 feature is available with a native GDB running on kernel version
2590 * GDB now has support for multi-byte and wide character sets on the
2591 target. Strings whose character type is wchar_t, char16_t, or
2592 char32_t are now correctly printed. GDB supports wide- and unicode-
2593 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2594 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2595 `printf'. This feature requires iconv to work properly; if your
2596 system does not have a working iconv, GDB can use GNU libiconv. See
2597 the installation instructions for more information.
2599 * GDB now supports automatic retrieval of shared library files from
2600 remote targets. To use this feature, specify a system root that begins
2601 with the `remote:' prefix, either via the `set sysroot' command or via
2602 the `--with-sysroot' configure-time option.
2604 * "info sharedlibrary" now takes an optional regex of libraries to show,
2605 and it now reports if a shared library has no debugging information.
2607 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2608 now complete on file names.
2610 * When completing in expressions, gdb will attempt to limit
2611 completions to allowable structure or union fields, where appropriate.
2612 For instance, consider:
2614 # struct example { int f1; double f2; };
2615 # struct example variable;
2618 If the user types TAB at the end of this command line, the available
2619 completions will be "f1" and "f2".
2621 * Inlined functions are now supported. They show up in backtraces, and
2622 the "step", "next", and "finish" commands handle them automatically.
2624 * GDB now supports the token-splicing (##) and stringification (#)
2625 operators when expanding macros. It also supports variable-arity
2628 * GDB now supports inspecting extra signal information, exported by
2629 the new $_siginfo convenience variable. The feature is currently
2630 implemented on linux ARM, i386 and amd64.
2632 * GDB can now display the VFP floating point registers and NEON vector
2633 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2634 can provide these registers (requires Linux 2.6.30 or later). Remote
2635 and simulator targets may also provide them.
2637 * New remote packets
2640 Search memory for a sequence of bytes.
2643 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2644 operation over reliable transport links. Use of this packet is
2645 controlled by the `set remote noack-packet' command.
2648 Kill the process with the specified process ID. Use this in preference
2649 to `k' when multiprocess protocol extensions are supported.
2652 Obtains additional operating system information
2656 Read or write additional signal information.
2658 * Removed remote protocol undocumented extension
2660 An undocumented extension to the remote protocol's `S' stop reply
2661 packet that permited the stub to pass a process id was removed.
2662 Remote servers should use the `T' stop reply packet instead.
2664 * GDB now supports multiple function calling conventions according to the
2665 DWARF-2 DW_AT_calling_convention function attribute.
2667 * The SH target utilizes the aforementioned change to distinguish between gcc
2668 and Renesas calling convention. It also adds the new CLI commands
2669 `set/show sh calling-convention'.
2671 * GDB can now read compressed debug sections, as produced by GNU gold
2672 with the --compress-debug-sections=zlib flag.
2674 * 64-bit core files are now supported on AIX.
2676 * Thread switching is now supported on Tru64.
2678 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2679 which will be allocated using malloc later in program execution.
2681 * The qXfer:libraries:read remote procotol packet now allows passing a
2682 list of section offsets.
2684 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2685 conditions handling signals delivered during attach or thread creation
2686 have also been fixed.
2688 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2689 From the user's standpoint, all unqualified instances of True and False
2690 are treated as the standard definitions, regardless of context.
2692 * GDB now parses C++ symbol and type names more flexibly. For
2695 template<typename T> class C { };
2698 GDB will now correctly handle all of:
2700 ptype C<char const *>
2701 ptype C<char const*>
2702 ptype C<const char *>
2703 ptype C<const char*>
2705 * New features in the GDB remote stub, gdbserver
2707 - The "--wrapper" command-line argument tells gdbserver to use a
2708 wrapper program to launch programs for debugging.
2710 - On PowerPC and S/390 targets, it is now possible to use a single
2711 gdbserver executable to debug both 32-bit and 64-bit programs.
2712 (This requires gdbserver itself to be built as a 64-bit executable.)
2714 - gdbserver uses the new noack protocol mode for TCP connections to
2715 reduce communications latency, if also supported and enabled in GDB.
2717 - Support for the sparc64-linux-gnu target is now included in
2720 - The amd64-linux build of gdbserver now supports debugging both
2721 32-bit and 64-bit programs.
2723 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2724 now support hardware watchpoints, and will use them automatically
2729 GDB now has support for scripting using Python. Whether this is
2730 available is determined at configure time.
2732 New GDB commands can now be written in Python.
2734 * Ada tasking support
2736 Ada tasks can now be inspected in GDB. The following commands have
2740 Print the list of Ada tasks.
2742 Print detailed information about task number N.
2744 Print the task number of the current task.
2746 Switch the context of debugging to task number N.
2748 * Support for user-defined prefixed commands. The "define" command can
2749 add new commands to existing prefixes, e.g. "target".
2751 * Multi-inferior, multi-process debugging.
2753 GDB now has generalized support for multi-inferior debugging. See
2754 "Debugging Multiple Inferiors" in the manual for more information.
2755 Although availability still depends on target support, the command
2756 set is more uniform now. The GNU/Linux specific multi-forks support
2757 has been migrated to this new framework. This implied some user
2758 visible changes; see "New commands" and also "Removed commands"
2761 * Target descriptions can now describe the target OS ABI. See the
2762 "Target Description Format" section in the user manual for more
2765 * Target descriptions can now describe "compatible" architectures
2766 to indicate that the target can execute applications for a different
2767 architecture in addition to those for the main target architecture.
2768 See the "Target Description Format" section in the user manual for
2771 * Multi-architecture debugging.
2773 GDB now includes general supports for debugging applications on
2774 hybrid systems that use more than one single processor architecture
2775 at the same time. Each such hybrid architecture still requires
2776 specific support to be added. The only hybrid architecture supported
2777 in this version of GDB is the Cell Broadband Engine.
2779 * GDB now supports integrated debugging of Cell/B.E. applications that
2780 use both the PPU and SPU architectures. To enable support for hybrid
2781 Cell/B.E. debugging, you need to configure GDB to support both the
2782 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2783 --enable-targets configure option.
2785 * Non-stop mode debugging.
2787 For some targets, GDB now supports an optional mode of operation in
2788 which you can examine stopped threads while other threads continue
2789 to execute freely. This is referred to as non-stop mode, with the
2790 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2791 section in the user manual for more information.
2793 To be able to support remote non-stop debugging, a remote stub needs
2794 to implement the non-stop mode remote protocol extensions, as
2795 described in the "Remote Non-Stop" section of the user manual. The
2796 GDB remote stub, gdbserver, has been adjusted to support these
2797 extensions on linux targets.
2799 * New commands (for set/show, see "New options" below)
2801 catch syscall [NAME(S) | NUMBER(S)]
2802 Catch system calls. Arguments, which should be names of system
2803 calls or their numbers, mean catch only those syscalls. Without
2804 arguments, every syscall will be caught. When the inferior issues
2805 any of the specified syscalls, GDB will stop and announce the system
2806 call, both when it is called and when its call returns. This
2807 feature is currently available with a native GDB running on the
2808 Linux Kernel, under the following architectures: x86, x86_64,
2809 PowerPC and PowerPC64.
2811 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2813 Search memory for a sequence of bytes.
2815 maint set python print-stack
2816 maint show python print-stack
2817 Show a stack trace when an error is encountered in a Python script.
2820 Invoke CODE by passing it to the Python interpreter.
2825 These allow macros to be defined, undefined, and listed
2829 Show operating system information about processes.
2832 List the inferiors currently under GDB's control.
2835 Switch focus to inferior number NUM.
2838 Detach from inferior number NUM.
2841 Kill inferior number NUM.
2845 set spu stop-on-load
2846 show spu stop-on-load
2847 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2849 set spu auto-flush-cache
2850 show spu auto-flush-cache
2851 Control whether to automatically flush the software-managed cache
2852 during Cell/B.E. debugging.
2854 set sh calling-convention
2855 show sh calling-convention
2856 Control the calling convention used when calling SH target functions.
2859 show debug timestamp
2860 Control display of timestamps with GDB debugging output.
2862 set disassemble-next-line
2863 show disassemble-next-line
2864 Control display of disassembled source lines or instructions when
2867 set remote noack-packet
2868 show remote noack-packet
2869 Set/show the use of remote protocol QStartNoAckMode packet. See above
2870 under "New remote packets."
2872 set remote query-attached-packet
2873 show remote query-attached-packet
2874 Control use of remote protocol `qAttached' (query-attached) packet.
2876 set remote read-siginfo-object
2877 show remote read-siginfo-object
2878 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2881 set remote write-siginfo-object
2882 show remote write-siginfo-object
2883 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2886 set remote reverse-continue
2887 show remote reverse-continue
2888 Control use of remote protocol 'bc' (reverse-continue) packet.
2890 set remote reverse-step
2891 show remote reverse-step
2892 Control use of remote protocol 'bs' (reverse-step) packet.
2894 set displaced-stepping
2895 show displaced-stepping
2896 Control displaced stepping mode. Displaced stepping is a way to
2897 single-step over breakpoints without removing them from the debuggee.
2898 Also known as "out-of-line single-stepping".
2901 show debug displaced
2902 Control display of debugging info for displaced stepping.
2904 maint set internal-error
2905 maint show internal-error
2906 Control what GDB does when an internal error is detected.
2908 maint set internal-warning
2909 maint show internal-warning
2910 Control what GDB does when an internal warning is detected.
2915 Use a wrapper program to launch programs for debugging.
2917 set multiple-symbols (all|ask|cancel)
2918 show multiple-symbols
2919 The value of this variable can be changed to adjust the debugger behavior
2920 when an expression or a breakpoint location contains an ambiguous symbol
2921 name (an overloaded function name, for instance).
2923 set breakpoint always-inserted
2924 show breakpoint always-inserted
2925 Keep breakpoints always inserted in the target, as opposed to inserting
2926 them when resuming the target, and removing them when the target stops.
2927 This option can improve debugger performance on slow remote targets.
2929 set arm fallback-mode (arm|thumb|auto)
2930 show arm fallback-mode
2931 set arm force-mode (arm|thumb|auto)
2933 These commands control how ARM GDB determines whether instructions
2934 are ARM or Thumb. The default for both settings is auto, which uses
2935 the current CPSR value for instructions without symbols; previous
2936 versions of GDB behaved as if "set arm fallback-mode arm".
2938 set disable-randomization
2939 show disable-randomization
2940 Standalone programs run with the virtual address space randomization enabled
2941 by default on some platforms. This option keeps the addresses stable across
2942 multiple debugging sessions.
2946 Control whether other threads are stopped or not when some thread hits
2951 Requests that asynchronous execution is enabled in the target, if available.
2952 In this case, it's possible to resume target in the background, and interact
2953 with GDB while the target is running. "show target-async" displays the
2954 current state of asynchronous execution of the target.
2956 set target-wide-charset
2957 show target-wide-charset
2958 The target-wide-charset is the name of the character set that GDB
2959 uses when printing characters whose type is wchar_t.
2961 set tcp auto-retry (on|off)
2963 set tcp connect-timeout
2964 show tcp connect-timeout
2965 These commands allow GDB to retry failed TCP connections to a remote stub
2966 with a specified timeout period; this is useful if the stub is launched
2967 in parallel with GDB but may not be ready to accept connections immediately.
2969 set libthread-db-search-path
2970 show libthread-db-search-path
2971 Control list of directories which GDB will search for appropriate
2974 set schedule-multiple (on|off)
2975 show schedule-multiple
2976 Allow GDB to resume all threads of all processes or only threads of
2977 the current process.
2981 Use more aggressive caching for accesses to the stack. This improves
2982 performance of remote debugging (particularly backtraces) without
2983 affecting correctness.
2985 set interactive-mode (on|off|auto)
2986 show interactive-mode
2987 Control whether GDB runs in interactive mode (on) or not (off).
2988 When in interactive mode, GDB waits for the user to answer all
2989 queries. Otherwise, GDB does not wait and assumes the default
2990 answer. When set to auto (the default), GDB determines which
2991 mode to use based on the stdin settings.
2996 For program forks, this is replaced by the new more generic `info
2997 inferiors' command. To list checkpoints, you can still use the
2998 `info checkpoints' command, which was an alias for the `info forks'
3002 Replaced by the new `inferior' command. To switch between
3003 checkpoints, you can still use the `restart' command, which was an
3004 alias for the `fork' command.
3007 This is removed, since some targets don't have a notion of
3008 processes. To switch between processes, you can still use the
3009 `inferior' command using GDB's own inferior number.
3012 For program forks, this is replaced by the new more generic `kill
3013 inferior' command. To delete a checkpoint, you can still use the
3014 `delete checkpoint' command, which was an alias for the `delete
3018 For program forks, this is replaced by the new more generic `detach
3019 inferior' command. To detach a checkpoint, you can still use the
3020 `detach checkpoint' command, which was an alias for the `detach
3023 * New native configurations
3025 x86/x86_64 Darwin i[34567]86-*-darwin*
3027 x86_64 MinGW x86_64-*-mingw*
3031 Lattice Mico32 lm32-*
3032 x86 DICOS i[34567]86-*-dicos*
3033 x86_64 DICOS x86_64-*-dicos*
3036 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3037 (mingw32ce) debugging.
3043 These commands were actually not implemented on any target.
3045 *** Changes in GDB 6.8
3047 * New native configurations
3049 NetBSD/hppa hppa*-*netbsd*
3050 Xtensa GNU/Linux xtensa*-*-linux*
3054 NetBSD/hppa hppa*-*-netbsd*
3055 Xtensa GNU/Lunux xtensa*-*-linux*
3057 * Change in command line behavior -- corefiles vs. process ids.
3059 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3060 attaching to process NUMBER fails, GDB no longer attempts to open a
3061 core file named NUMBER. Attaching to a program using the -c option
3062 is no longer supported. Instead, use the '-p' or '--pid' options.
3064 * GDB can now be built as a native debugger for debugging Windows x86
3065 (mingw32) Portable Executable (PE) programs.
3067 * Pending breakpoints no longer change their number when their address
3070 * GDB now supports breakpoints with multiple locations,
3071 including breakpoints on C++ constructors, inside C++ templates,
3072 and in inlined functions.
3074 * GDB's ability to debug optimized code has been improved. GDB more
3075 accurately identifies function bodies and lexical blocks that occupy
3076 more than one contiguous range of addresses.
3078 * Target descriptions can now describe registers for PowerPC.
3080 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3081 registers on PowerPC targets.
3083 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3084 targets even when the libthread_db library is not available.
3086 * The GDB remote stub, gdbserver, now supports the new file transfer
3087 commands (remote put, remote get, and remote delete).
3089 * The GDB remote stub, gdbserver, now supports run and attach in
3090 extended-remote mode.
3092 * hppa*64*-*-hpux11* target broken
3093 The debugger is unable to start a program and fails with the following
3094 error: "Error trying to get information about dynamic linker".
3095 The gdb-6.7 release is also affected.
3097 * GDB now supports the --enable-targets= configure option to allow
3098 building a single GDB executable that supports multiple remote
3099 target architectures.
3101 * GDB now supports debugging C and C++ programs which use the
3102 Decimal Floating Point extension. In addition, the PowerPC target
3103 now has a set of pseudo-registers to inspect decimal float values
3104 stored in two consecutive float registers.
3106 * The -break-insert MI command can optionally create pending
3109 * Improved support for debugging Ada
3110 Many improvements to the Ada language support have been made. These
3112 - Better support for Ada2005 interface types
3113 - Improved handling of arrays and slices in general
3114 - Better support for Taft-amendment types
3115 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3117 - Improved command completion in Ada
3120 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3125 set print frame-arguments (all|scalars|none)
3126 show print frame-arguments
3127 The value of this variable can be changed to control which argument
3128 values should be printed by the debugger when displaying a frame.
3133 Transfer files to and from a remote target, and delete remote files.
3140 Transfer files to and from a remote target, and delete remote files.
3142 * New remote packets
3149 Open, close, read, write, and delete files on the remote system.
3152 Attach to an existing process on the remote system, in extended-remote
3156 Run a new process on the remote system, in extended-remote mode.
3158 *** Changes in GDB 6.7
3160 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3161 bfd, libiberty and opcodes, as revealed by static analysis donated by
3162 Coverity, Inc. (http://scan.coverity.com).
3164 * When looking up multiply-defined global symbols, GDB will now prefer the
3165 symbol definition in the current shared library if it was built using the
3166 -Bsymbolic linker option.
3168 * When the Text User Interface (TUI) is not configured, GDB will now
3169 recognize the -tui command-line option and print a message that the TUI
3172 * The GDB remote stub, gdbserver, now has lower overhead for high
3173 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3175 * GDB for MIPS targets now autodetects whether a remote target provides
3176 32-bit or 64-bit register values.
3178 * Support for C++ member pointers has been improved.
3180 * GDB now understands XML target descriptions, which specify the
3181 target's overall architecture. GDB can read a description from
3182 a local file or over the remote serial protocol.
3184 * Vectors of single-byte data use a new integer type which is not
3185 automatically displayed as character or string data.
3187 * The /s format now works with the print command. It displays
3188 arrays of single-byte integers and pointers to single-byte integers
3191 * Target descriptions can now describe target-specific registers,
3192 for architectures which have implemented the support (currently
3193 only ARM, M68K, and MIPS).
3195 * GDB and the GDB remote stub, gdbserver, now support the XScale
3198 * The GDB remote stub, gdbserver, has been updated to support
3199 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3200 has been rewritten to use the standard GDB remote protocol.
3202 * GDB can now step into C++ functions which are called through thunks.
3204 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3206 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3207 layout. It also supports a TextSeg= and DataSeg= response when only
3208 segment base addresses (rather than offsets) are available.
3210 * The /i format now outputs any trailing branch delay slot instructions
3211 immediately following the last instruction within the count specified.
3213 * The GDB remote protocol "T" stop reply packet now supports a
3214 "library" response. Combined with the new "qXfer:libraries:read"
3215 packet, this response allows GDB to debug shared libraries on targets
3216 where the operating system manages the list of loaded libraries (e.g.
3217 Windows and SymbianOS).
3219 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3220 (DLLs) on Windows and Windows CE targets.
3222 * GDB now supports a faster verification that a .debug file matches its binary
3223 according to its build-id signature, if the signature is present.
3229 Enable or disable hardware flow control (RTS/CTS) on the serial port
3230 when debugging using remote targets.
3232 set mem inaccessible-by-default
3233 show mem inaccessible-by-default
3234 If the target supplies a memory map, for instance via the remote
3235 protocol's "qXfer:memory-map:read" packet, setting this variable
3236 prevents GDB from accessing memory outside the memory map. This
3237 is useful for targets with memory mapped registers or which react
3238 badly to accesses of unmapped address space.
3240 set breakpoint auto-hw
3241 show breakpoint auto-hw
3242 If the target supplies a memory map, for instance via the remote
3243 protocol's "qXfer:memory-map:read" packet, setting this variable
3244 lets GDB use hardware breakpoints automatically for memory regions
3245 where it can not use software breakpoints. This covers both the
3246 "break" command and internal breakpoints used for other commands
3247 including "next" and "finish".
3250 catch exception unhandled
3251 Stop the program execution when Ada exceptions are raised.
3254 Stop the program execution when an Ada assertion failed.
3258 Set an alternate system root for target files. This is a more
3259 general version of "set solib-absolute-prefix", which is now
3260 an alias to "set sysroot".
3263 Provide extended SPU facility status information. This set of
3264 commands is available only when debugging the Cell/B.E. SPU
3267 * New native configurations
3269 OpenBSD/sh sh*-*openbsd*
3272 unset tdesc filename
3274 Use the specified local file as an XML target description, and do
3275 not query the target for its built-in description.
3279 OpenBSD/sh sh*-*-openbsd*
3280 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3281 Toshiba Media Processor mep-elf
3283 * New remote packets
3286 Ignore the specified signals; pass them directly to the debugged program
3287 without stopping other threads or reporting them to GDB.
3289 qXfer:features:read:
3290 Read an XML target description from the target, which describes its
3295 Read or write contents of an spufs file on the target system. These
3296 packets are available only on the Cell/B.E. SPU architecture.
3298 qXfer:libraries:read:
3299 Report the loaded shared libraries. Combined with new "T" packet
3300 response, this packet allows GDB to debug shared libraries on
3301 targets where the operating system manages the list of loaded
3302 libraries (e.g. Windows and SymbianOS).
3306 Support for these obsolete configurations has been removed.
3314 i[34567]86-*-lynxos*
3315 i[34567]86-*-netware*
3316 i[34567]86-*-sco3.2v5*
3317 i[34567]86-*-sco3.2v4*
3319 i[34567]86-*-sysv4.2*
3322 i[34567]86-*-unixware2*
3323 i[34567]86-*-unixware*
3332 * Other removed features
3339 Various m68k-only ROM monitors.
3346 Various Renesas ROM monitors and debugging interfaces for SH and
3351 Support for a Macraigor serial interface to on-chip debugging.
3352 GDB does not directly support the newer parallel or USB
3357 A debug information format. The predecessor to DWARF 2 and
3358 DWARF 3, which are still supported.
3360 Support for the HP aCC compiler on HP-UX/PA-RISC
3362 SOM-encapsulated symbolic debugging information, automatic
3363 invocation of pxdb, and the aCC custom C++ ABI. This does not
3364 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3365 with aCC can still be debugged on an assembly level.
3367 MIPS ".pdr" sections
3369 A MIPS-specific format used to describe stack frame layout
3370 in debugging information.
3374 GDB could work with an older version of Guile to debug
3375 the interpreter and Scheme programs running in it.
3377 set mips stack-arg-size
3378 set mips saved-gpreg-size
3380 Use "set mips abi" to control parameter passing for MIPS.
3382 *** Changes in GDB 6.6
3387 Cell Broadband Engine SPU spu-elf
3389 * GDB can now be configured as a cross-debugger targeting native Windows
3390 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3391 running on a Windows system over TCP/IP to debug Windows programs.
3393 * The GDB remote stub, gdbserver, has been updated to support Windows and
3394 Cygwin debugging. Both single-threaded and multi-threaded programs are
3397 * The "set trust-readonly-sections" command works again. This command was
3398 broken in GDB 6.3, 6.4, and 6.5.
3400 * The "load" command now supports writing to flash memory, if the remote
3401 stub provides the required support.
3403 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3404 longer requires symbolic debug information (e.g. DWARF-2).
3409 unset substitute-path
3410 show substitute-path
3411 Manage a list of substitution rules that GDB uses to rewrite the name
3412 of the directories where the sources are located. This can be useful
3413 for instance when the sources were moved to a different location
3414 between compilation and debugging.
3418 Print each CLI command as it is executed. Each command is prefixed with
3419 a number of `+' symbols representing the nesting depth.
3420 The source command now has a `-v' option to enable the same feature.
3424 The ARM Demon monitor support (RDP protocol, "target rdp").
3426 Kernel Object Display, an embedded debugging feature which only worked with
3427 an obsolete version of Cisco IOS.
3429 The 'set download-write-size' and 'show download-write-size' commands.
3431 * New remote packets
3434 Tell a stub about GDB client features, and request remote target features.
3435 The first feature implemented is PacketSize, which allows the target to
3436 specify the size of packets it can handle - to minimize the number of
3437 packets required and improve performance when connected to a remote
3441 Fetch an OS auxilliary vector from the remote stub. This packet is a
3442 more efficient replacement for qPart:auxv:read.
3444 qXfer:memory-map:read:
3445 Fetch a memory map from the remote stub, including information about
3446 RAM, ROM, and flash memory devices.
3451 Erase and program a flash memory device.
3453 * Removed remote packets
3456 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3457 used it, and only gdbserver implemented it.
3459 *** Changes in GDB 6.5
3463 Renesas M32C/M16C m32c-elf
3465 Morpho Technologies ms1 ms1-elf
3469 init-if-undefined Initialize a convenience variable, but
3470 only if it doesn't already have a value.
3472 The following commands are presently only implemented for native GNU/Linux:
3474 checkpoint Save a snapshot of the program state.
3476 restart <n> Return the program state to a
3477 previously saved state.
3479 info checkpoints List currently saved checkpoints.
3481 delete-checkpoint <n> Delete a previously saved checkpoint.
3483 set|show detach-on-fork Tell gdb whether to detach from a newly
3484 forked process, or to keep debugging it.
3486 info forks List forks of the user program that
3487 are available to be debugged.
3489 fork <n> Switch to debugging one of several
3490 forks of the user program that are
3491 available to be debugged.
3493 delete-fork <n> Delete a fork from the list of forks
3494 that are available to be debugged (and
3495 kill the forked process).
3497 detach-fork <n> Delete a fork from the list of forks
3498 that are available to be debugged (and
3499 allow the process to continue).
3503 Morpho Technologies ms2 ms1-elf
3505 * Improved Windows host support
3507 GDB now builds as a cross debugger hosted on i686-mingw32, including
3508 native console support, and remote communications using either
3509 network sockets or serial ports.
3511 * Improved Modula-2 language support
3513 GDB can now print most types in the Modula-2 syntax. This includes:
3514 basic types, set types, record types, enumerated types, range types,
3515 pointer types and ARRAY types. Procedure var parameters are correctly
3516 printed and hexadecimal addresses and character constants are also
3517 written in the Modula-2 syntax. Best results can be obtained by using
3518 GNU Modula-2 together with the -gdwarf-2 command line option.
3522 The ARM rdi-share module.
3524 The Netware NLM debug server.
3526 *** Changes in GDB 6.4
3528 * New native configurations
3530 OpenBSD/arm arm*-*-openbsd*
3531 OpenBSD/mips64 mips64-*-openbsd*
3535 Morpho Technologies ms1 ms1-elf
3537 * New command line options
3539 --batch-silent As for --batch, but totally silent.
3540 --return-child-result The debugger will exist with the same value
3541 the child (debugged) program exited with.
3542 --eval-command COMMAND, -ex COMMAND
3543 Execute a single GDB CLI command. This may be
3544 specified multiple times and in conjunction
3545 with the --command (-x) option.
3547 * Deprecated commands removed
3549 The following commands, that were deprecated in 2000, have been
3553 set|show arm disassembly-flavor set|show arm disassembler
3554 othernames set arm disassembler
3555 set|show remotedebug set|show debug remote
3556 set|show archdebug set|show debug arch
3557 set|show eventdebug set|show debug event
3560 * New BSD user-level threads support
3562 It is now possible to debug programs using the user-level threads
3563 library on OpenBSD and FreeBSD. Currently supported (target)
3566 FreeBSD/amd64 x86_64-*-freebsd*
3567 FreeBSD/i386 i386-*-freebsd*
3568 OpenBSD/i386 i386-*-openbsd*
3570 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3571 are not yet supported.
3573 * New support for Matsushita MN10300 w/sim added
3574 (Work in progress). mn10300-elf.
3576 * REMOVED configurations and files
3578 VxWorks and the XDR protocol *-*-vxworks
3579 Motorola MCORE mcore-*-*
3580 National Semiconductor NS32000 ns32k-*-*
3582 * New "set print array-indexes" command
3584 After turning this setting "on", GDB prints the index of each element
3585 when displaying arrays. The default is "off" to preserve the previous
3588 * VAX floating point support
3590 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3592 * User-defined command support
3594 In addition to using $arg0..$arg9 for argument passing, it is now possible
3595 to use $argc to determine now many arguments have been passed. See the
3596 section on user-defined commands in the user manual for more information.
3598 *** Changes in GDB 6.3:
3600 * New command line option
3602 GDB now accepts -l followed by a number to set the timeout for remote
3605 * GDB works with GCC -feliminate-dwarf2-dups
3607 GDB now supports a more compact representation of DWARF-2 debug
3608 information using DW_FORM_ref_addr references. These are produced
3609 by GCC with the option -feliminate-dwarf2-dups and also by some
3610 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3611 to use -feliminate-dwarf2-dups.
3613 * Internationalization
3615 When supported by the host system, GDB will be built with
3616 internationalization (libintl). The task of marking up the sources is
3617 continued, we're looking forward to our first translation.
3621 Initial support for debugging programs compiled with the GNAT
3622 implementation of the Ada programming language has been integrated
3623 into GDB. In this release, support is limited to expression evaluation.
3625 * New native configurations
3627 GNU/Linux/m32r m32r-*-linux-gnu
3631 GDB's remote protocol now includes support for the 'p' packet. This
3632 packet is used to fetch individual registers from a remote inferior.
3634 * END-OF-LIFE registers[] compatibility module
3636 GDB's internal register infrastructure has been completely rewritten.
3637 The new infrastructure making possible the implementation of key new
3638 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3641 GDB 6.3 will be the last release to include the the registers[]
3642 compatibility module that allowed out-of-date configurations to
3643 continue to work. This change directly impacts the following
3653 powerpc bdm protocol
3655 Unless there is activity to revive these configurations, they will be
3656 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3658 * OBSOLETE configurations and files
3660 Configurations that have been declared obsolete in this release have
3661 been commented out. Unless there is activity to revive these
3662 configurations, the next release of GDB will have their sources
3663 permanently REMOVED.
3672 *** Changes in GDB 6.2.1:
3674 * MIPS `break main; run' gave an heuristic-fence-post warning
3676 When attempting to run even a simple program, a warning about
3677 heuristic-fence-post being hit would be reported. This problem has
3680 * MIPS IRIX 'long double' crashed GDB
3682 When examining a long double variable, GDB would get a segmentation
3683 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3684 IRIX long double values).
3688 A bug in the VAX stack code was causing problems with the "next"
3689 command. This problem has been fixed.
3691 *** Changes in GDB 6.2:
3693 * Fix for ``many threads''
3695 On GNU/Linux systems that use the NPTL threads library, a program
3696 rapidly creating and deleting threads would confuse GDB leading to the
3699 ptrace: No such process.
3700 thread_db_get_info: cannot get thread info: generic error
3702 This problem has been fixed.
3704 * "-async" and "-noasync" options removed.
3706 Support for the broken "-noasync" option has been removed (it caused
3709 * New ``start'' command.
3711 This command runs the program until the begining of the main procedure.
3713 * New BSD Kernel Data Access Library (libkvm) interface
3715 Using ``target kvm'' it is now possible to debug kernel core dumps and
3716 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3717 platforms. Currently supported (native-only) configurations are:
3719 FreeBSD/amd64 x86_64-*-freebsd*
3720 FreeBSD/i386 i?86-*-freebsd*
3721 NetBSD/i386 i?86-*-netbsd*
3722 NetBSD/m68k m68*-*-netbsd*
3723 NetBSD/sparc sparc-*-netbsd*
3724 OpenBSD/amd64 x86_64-*-openbsd*
3725 OpenBSD/i386 i?86-*-openbsd*
3726 OpenBSD/m68k m68*-openbsd*
3727 OpenBSD/sparc sparc-*-openbsd*
3729 * Signal trampoline code overhauled
3731 Many generic problems with GDB's signal handling code have been fixed.
3732 These include: backtraces through non-contiguous stacks; recognition
3733 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3734 call; backtrace through a signal trampoline; step into and out of
3735 signal handlers; and single-stepping in the signal trampoline.
3737 Please note that kernel bugs are a limiting factor here. These
3738 features have been shown to work on an s390 GNU/Linux system that
3739 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3741 * Cygwin support for DWARF 2 added.
3743 * New native configurations
3745 GNU/Linux/hppa hppa*-*-linux*
3746 OpenBSD/hppa hppa*-*-openbsd*
3747 OpenBSD/m68k m68*-*-openbsd*
3748 OpenBSD/m88k m88*-*-openbsd*
3749 OpenBSD/powerpc powerpc-*-openbsd*
3750 NetBSD/vax vax-*-netbsd*
3751 OpenBSD/vax vax-*-openbsd*
3753 * END-OF-LIFE frame compatibility module
3755 GDB's internal frame infrastructure has been completely rewritten.
3756 The new infrastructure making it possible to support key new features
3757 including DWARF 2 Call Frame Information. To aid in the task of
3758 migrating old configurations to this new infrastructure, a
3759 compatibility module, that allowed old configurations to continue to
3760 work, was also included.
3762 GDB 6.2 will be the last release to include this frame compatibility
3763 module. This change directly impacts the following configurations:
3773 Unless there is activity to revive these configurations, they will be
3774 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3776 * REMOVED configurations and files
3778 Sun 3, running SunOS 3 m68*-*-sunos3*
3779 Sun 3, running SunOS 4 m68*-*-sunos4*
3780 Sun 2, running SunOS 3 m68000-*-sunos3*
3781 Sun 2, running SunOS 4 m68000-*-sunos4*
3782 Motorola 680x0 running LynxOS m68*-*-lynxos*
3783 AT&T 3b1/Unix pc m68*-att-*
3784 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3785 decstation mips-dec-* mips-little-*
3786 riscos mips-*-riscos* mips-*-sysv*
3787 sonymips mips-sony-*
3788 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3790 *** Changes in GDB 6.1.1:
3792 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3794 The TUI (Text-mode User Interface) is now built as part of a default
3795 GDB configuration. It is enabled by either selecting the TUI with the
3796 command line option "-i=tui" or by running the separate "gdbtui"
3797 program. For more information on the TUI, see the manual "Debugging
3800 * Pending breakpoint support (also included in GDB 6.1)
3802 Support has been added to allow you to specify breakpoints in shared
3803 libraries that have not yet been loaded. If a breakpoint location
3804 cannot be found, and the "breakpoint pending" option is set to auto,
3805 GDB queries you if you wish to make the breakpoint pending on a future
3806 shared-library load. If and when GDB resolves the breakpoint symbol,
3807 the pending breakpoint is removed as one or more regular breakpoints
3810 Pending breakpoints are very useful for GCJ Java debugging.
3812 * Fixed ISO-C build problems
3814 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3815 non ISO-C code that stopped them being built using a more strict ISO-C
3816 compiler (e.g., IBM's C compiler).
3818 * Fixed build problem on IRIX 5
3820 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3821 wasn't able to compile compile on an IRIX 5 system.
3823 * Added execute permission to gdb/gdbserver/configure
3825 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3826 permission. This bug would cause configure to fail on a number of
3827 systems (Solaris, IRIX). Ref: server/519.
3829 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3831 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3832 has been updated to use constant array sizes.
3834 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3836 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3837 its generated DWARF Call Frame Info. This encoding was causing GDB to
3838 panic, that panic has been fixed. Ref: gdb/1628.
3840 * Fixed a problem when examining parameters in shared library code.
3842 When examining parameters in optimized shared library code generated
3843 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3844 not available''. GDB now correctly displays the variable's value.
3846 *** Changes in GDB 6.1:
3848 * Removed --with-mmalloc
3850 Support for the mmalloc memory manager has been removed, as it
3851 conflicted with the internal gdb byte cache.
3853 * Changes in AMD64 configurations
3855 The AMD64 target now includes the %cs and %ss registers. As a result
3856 the AMD64 remote protocol has changed; this affects the floating-point
3857 and SSE registers. If you rely on those registers for your debugging,
3858 you should upgrade gdbserver on the remote side.
3860 * Revised SPARC target
3862 The SPARC target has been completely revised, incorporating the
3863 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3864 support for LynxOS and SunOS 4 has been dropped. Calling functions
3865 from within GDB on operating systems with a non-executable stack
3866 (Solaris, OpenBSD) now works.
3870 GDB has a new C++ demangler which does a better job on the mangled
3871 names generated by current versions of g++. It also runs faster, so
3872 with this and other changes gdb should now start faster on large C++
3875 * DWARF 2 Location Expressions
3877 GDB support for location expressions has been extended to support function
3878 arguments and frame bases. Older versions of GDB could crash when they
3881 * C++ nested types and namespaces
3883 GDB's support for nested types and namespaces in C++ has been
3884 improved, especially if you use the DWARF 2 debugging format. (This
3885 is the default for recent versions of GCC on most platforms.)
3886 Specifically, if you have a class "Inner" defined within a class or
3887 namespace "Outer", then GDB realizes that the class's name is
3888 "Outer::Inner", not simply "Inner". This should greatly reduce the
3889 frequency of complaints about not finding RTTI symbols. In addition,
3890 if you are stopped at inside of a function defined within a namespace,
3891 GDB modifies its name lookup accordingly.
3893 * New native configurations
3895 NetBSD/amd64 x86_64-*-netbsd*
3896 OpenBSD/amd64 x86_64-*-openbsd*
3897 OpenBSD/alpha alpha*-*-openbsd*
3898 OpenBSD/sparc sparc-*-openbsd*
3899 OpenBSD/sparc64 sparc64-*-openbsd*
3901 * New debugging protocols
3903 M32R with SDI protocol m32r-*-elf*
3905 * "set prompt-escape-char" command deleted.
3907 The command "set prompt-escape-char" has been deleted. This command,
3908 and its very obscure effet on GDB's prompt, was never documented,
3909 tested, nor mentioned in the NEWS file.
3911 * OBSOLETE configurations and files
3913 Configurations that have been declared obsolete in this release have
3914 been commented out. Unless there is activity to revive these
3915 configurations, the next release of GDB will have their sources
3916 permanently REMOVED.
3918 Sun 3, running SunOS 3 m68*-*-sunos3*
3919 Sun 3, running SunOS 4 m68*-*-sunos4*
3920 Sun 2, running SunOS 3 m68000-*-sunos3*
3921 Sun 2, running SunOS 4 m68000-*-sunos4*
3922 Motorola 680x0 running LynxOS m68*-*-lynxos*
3923 AT&T 3b1/Unix pc m68*-att-*
3924 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3925 decstation mips-dec-* mips-little-*
3926 riscos mips-*-riscos* mips-*-sysv*
3927 sonymips mips-sony-*
3928 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3930 * REMOVED configurations and files
3932 SGI Irix-4.x mips-sgi-irix4 or iris4
3933 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3934 Z8000 simulator z8k-zilog-none or z8ksim
3935 Matsushita MN10200 w/simulator mn10200-*-*
3936 H8/500 simulator h8500-hitachi-hms or h8500hms
3937 HP/PA running BSD hppa*-*-bsd*
3938 HP/PA running OSF/1 hppa*-*-osf*
3939 HP/PA Pro target hppa*-*-pro*
3940 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3941 386BSD i[3456]86-*-bsd*
3942 Sequent family i[3456]86-sequent-sysv4*
3943 i[3456]86-sequent-sysv*
3944 i[3456]86-sequent-bsd*
3945 SPARC running LynxOS sparc-*-lynxos*
3946 SPARC running SunOS 4 sparc-*-sunos4*
3947 Tsqware Sparclet sparclet-*-*
3948 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3950 *** Changes in GDB 6.0:
3954 Support for debugging the Objective-C programming language has been
3955 integrated into GDB.
3957 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3959 DWARF 2's Call Frame Information makes available compiler generated
3960 information that more exactly describes the program's run-time stack.
3961 By using this information, GDB is able to provide more robust stack
3964 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3965 have been updated to use a new backtrace mechanism which includes
3966 DWARF 2 CFI support.
3970 GDB's remote protocol has been extended to include support for hosted
3971 file I/O (where the remote target uses GDB's file system). See GDB's
3972 remote protocol documentation for details.
3974 * All targets using the new architecture framework.
3976 All of GDB's targets have been updated to use the new internal
3977 architecture framework. The way is now open for future GDB releases
3978 to include cross-architecture native debugging support (i386 on amd64,
3981 * GNU/Linux's Thread Local Storage (TLS)
3983 GDB now includes support for for the GNU/Linux implementation of
3984 per-thread variables.
3986 * GNU/Linux's Native POSIX Thread Library (NPTL)
3988 GDB's thread code has been updated to work with either the new
3989 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3991 * Separate debug info.
3993 GDB, in conjunction with BINUTILS, now supports a mechanism for
3994 automatically loading debug information from a separate file. Instead
3995 of shipping full debug and non-debug versions of system libraries,
3996 system integrators can now instead ship just the stripped libraries
3997 and optional debug files.
3999 * DWARF 2 Location Expressions
4001 DWARF 2 Location Expressions allow the compiler to more completely
4002 describe the location of variables (even in optimized code) to the
4005 GDB now includes preliminary support for location expressions (support
4006 for DW_OP_piece is still missing).
4010 A number of long standing bugs that caused GDB to die while starting a
4011 Java application have been fixed. GDB's Java support is now
4012 considered "useable".
4014 * GNU/Linux support for fork, vfork, and exec.
4016 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4017 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4020 * GDB supports logging output to a file
4022 There are two new commands, "set logging" and "show logging", which can be
4023 used to capture GDB's output to a file.
4025 * The meaning of "detach" has changed for gdbserver
4027 The "detach" command will now resume the application, as documented. To
4028 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4031 * d10v, m68hc11 `regs' command deprecated
4033 The `info registers' command has been updated so that it displays the
4034 registers using a format identical to the old `regs' command.
4038 A new command, "maint set profile on/off", has been added. This command can
4039 be used to enable or disable profiling while running GDB, to profile a
4040 session or a set of commands. In addition there is a new configure switch,
4041 "--enable-profiling", which will cause GDB to be compiled with profiling
4042 data, for more informative profiling results.
4044 * Default MI syntax changed to "mi2".
4046 The default MI (machine interface) syntax, enabled by the command line
4047 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4048 "mi1", can be enabled by specifying the option "-i=mi1".
4050 Support for the original "mi0" syntax (included in GDB 5.0) has been
4053 Fix for gdb/192: removed extraneous space when displaying frame level.
4054 Fix for gdb/672: update changelist is now output in mi list format.
4055 Fix for gdb/702: a -var-assign that updates the value now shows up
4056 in a subsequent -var-update.
4058 * New native configurations.
4060 FreeBSD/amd64 x86_64-*-freebsd*
4062 * Multi-arched targets.
4064 HP/PA HPUX11 hppa*-*-hpux*
4065 Renesas M32R/D w/simulator m32r-*-elf*
4067 * OBSOLETE configurations and files
4069 Configurations that have been declared obsolete in this release have
4070 been commented out. Unless there is activity to revive these
4071 configurations, the next release of GDB will have their sources
4072 permanently REMOVED.
4074 Z8000 simulator z8k-zilog-none or z8ksim
4075 Matsushita MN10200 w/simulator mn10200-*-*
4076 H8/500 simulator h8500-hitachi-hms or h8500hms
4077 HP/PA running BSD hppa*-*-bsd*
4078 HP/PA running OSF/1 hppa*-*-osf*
4079 HP/PA Pro target hppa*-*-pro*
4080 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4081 Sequent family i[3456]86-sequent-sysv4*
4082 i[3456]86-sequent-sysv*
4083 i[3456]86-sequent-bsd*
4084 Tsqware Sparclet sparclet-*-*
4085 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4087 * REMOVED configurations and files
4090 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4091 IBM AIX PS/2 i[3456]86-*-aix
4092 i386 running Mach 3.0 i[3456]86-*-mach3*
4093 i386 running Mach i[3456]86-*-mach*
4094 i386 running OSF/1 i[3456]86-*osf1mk*
4095 HP/Apollo 68k Family m68*-apollo*-sysv*,
4097 m68*-hp-bsd*, m68*-hp-hpux*
4098 Argonaut Risc Chip (ARC) arc-*-*
4099 Mitsubishi D30V d30v-*-*
4100 Fujitsu FR30 fr30-*-elf*
4101 OS/9000 i[34]86-*-os9k
4102 I960 with MON960 i960-*-coff
4104 * MIPS $fp behavior changed
4106 The convenience variable $fp, for the MIPS, now consistently returns
4107 the address of the current frame's base. Previously, depending on the
4108 context, $fp could refer to either $sp or the current frame's base
4109 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4110 The GNU Source-Level Debugger''.
4112 *** Changes in GDB 5.3:
4114 * GNU/Linux shared library multi-threaded performance improved.
4116 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4117 `/proc', in preference to `ptrace' for memory reads. This may result
4118 in an improvement in the start-up time of multi-threaded, shared
4119 library applications when run under GDB. One GDB user writes: ``loads
4120 shared libs like mad''.
4122 * ``gdbserver'' now supports multi-threaded applications on some targets
4124 Support for debugging multi-threaded applications which use
4125 the GNU/Linux LinuxThreads package has been added for
4126 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4127 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4129 * GDB now supports C/C++ preprocessor macros.
4131 GDB now expands preprocessor macro invocations in C/C++ expressions,
4132 and provides various commands for showing macro definitions and how
4135 The new command `macro expand EXPRESSION' expands any macro
4136 invocations in expression, and shows the result.
4138 The new command `show macro MACRO-NAME' shows the definition of the
4139 macro named MACRO-NAME, and where it was defined.
4141 Most compilers don't include information about macros in the debugging
4142 information by default. In GCC 3.1, for example, you need to compile
4143 your program with the options `-gdwarf-2 -g3'. If the macro
4144 information is present in the executable, GDB will read it.
4146 * Multi-arched targets.
4148 DEC Alpha (partial) alpha*-*-*
4149 DEC VAX (partial) vax-*-*
4151 National Semiconductor NS32000 (partial) ns32k-*-*
4152 Motorola 68000 (partial) m68k-*-*
4153 Motorola MCORE mcore-*-*
4157 Fujitsu FRV architecture added by Red Hat frv*-*-*
4160 * New native configurations
4162 Alpha NetBSD alpha*-*-netbsd*
4163 SH NetBSD sh*-*-netbsdelf*
4164 MIPS NetBSD mips*-*-netbsd*
4165 UltraSPARC NetBSD sparc64-*-netbsd*
4167 * OBSOLETE configurations and files
4169 Configurations that have been declared obsolete in this release have
4170 been commented out. Unless there is activity to revive these
4171 configurations, the next release of GDB will have their sources
4172 permanently REMOVED.
4174 Mitsubishi D30V d30v-*-*
4175 OS/9000 i[34]86-*-os9k
4176 IBM AIX PS/2 i[3456]86-*-aix
4177 Fujitsu FR30 fr30-*-elf*
4178 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4179 Argonaut Risc Chip (ARC) arc-*-*
4180 i386 running Mach 3.0 i[3456]86-*-mach3*
4181 i386 running Mach i[3456]86-*-mach*
4182 i386 running OSF/1 i[3456]86-*osf1mk*
4183 HP/Apollo 68k Family m68*-apollo*-sysv*,
4185 m68*-hp-bsd*, m68*-hp-hpux*
4186 I960 with MON960 i960-*-coff
4188 * OBSOLETE languages
4190 CHILL, a Pascal like language used by telecommunications companies.
4192 * REMOVED configurations and files
4194 AMD 29k family via UDI a29k-amd-udi, udi29k
4195 A29K VxWorks a29k-*-vxworks
4196 AMD 29000 embedded, using EBMON a29k-none-none
4197 AMD 29000 embedded with COFF a29k-none-coff
4198 AMD 29000 embedded with a.out a29k-none-aout
4200 testsuite/gdb.hp/gdb.threads-hp/ directory
4202 * New command "set max-user-call-depth <nnn>"
4204 This command allows the user to limit the call depth of user-defined
4205 commands. The default is 1024.
4207 * Changes in FreeBSD/i386 native debugging.
4209 Support for the "generate-core-file" has been added.
4211 * New commands "dump", "append", and "restore".
4213 These commands allow data to be copied from target memory
4214 to a bfd-format or binary file (dump and append), and back
4215 from a file into memory (restore).
4217 * Improved "next/step" support on multi-processor Alpha Tru64.
4219 The previous single-step mechanism could cause unpredictable problems,
4220 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4221 of a software single-step mechanism prevents this.
4223 *** Changes in GDB 5.2.1:
4231 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4232 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4233 Fix, by Joel Brobecker imported from mainline.
4235 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4236 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4237 Fix, by Fred Fish, imported from mainline.
4239 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4240 Surprisingly enough, it works now.
4241 By Michal Ludvig, imported from mainline.
4243 i386 hardware watchpoint support:
4244 avoid misses on second run for some targets.
4245 By Pierre Muller, imported from mainline.
4247 *** Changes in GDB 5.2:
4249 * New command "set trust-readonly-sections on[off]".
4251 This command is a hint that tells gdb that read-only sections
4252 really are read-only (ie. that their contents will not change).
4253 In this mode, gdb will go to the object file rather than the
4254 target to read memory from read-only sections (such as ".text").
4255 This can be a significant performance improvement on some
4256 (notably embedded) targets.
4258 * New command "generate-core-file" (or "gcore").
4260 This new gdb command allows the user to drop a core file of the child
4261 process state at any time. So far it's been implemented only for
4262 GNU/Linux and Solaris, but should be relatively easily ported to other
4263 hosts. Argument is core file name (defaults to core.<pid>).
4265 * New command line option
4267 GDB now accepts --pid or -p followed by a process id.
4269 * Change in command line behavior -- corefiles vs. process ids.
4271 There is a subtle behavior in the way in which GDB handles
4272 command line arguments. The first non-flag argument is always
4273 a program to debug, but the second non-flag argument may either
4274 be a corefile or a process id. Previously, GDB would attempt to
4275 open the second argument as a corefile, and if that failed, would
4276 issue a superfluous error message and then attempt to attach it as
4277 a process. Now, if the second argument begins with a non-digit,
4278 it will be treated as a corefile. If it begins with a digit,
4279 GDB will attempt to attach it as a process, and if no such process
4280 is found, will then attempt to open it as a corefile.
4282 * Changes in ARM configurations.
4284 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4285 configuration is fully multi-arch.
4287 * New native configurations
4289 ARM NetBSD arm*-*-netbsd*
4290 x86 OpenBSD i[3456]86-*-openbsd*
4291 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4292 Sparc64 running FreeBSD sparc64-*-freebsd*
4296 Sanyo XStormy16 xstormy16-elf
4298 * OBSOLETE configurations and files
4300 Configurations that have been declared obsolete in this release have
4301 been commented out. Unless there is activity to revive these
4302 configurations, the next release of GDB will have their sources
4303 permanently REMOVED.
4305 AMD 29k family via UDI a29k-amd-udi, udi29k
4306 A29K VxWorks a29k-*-vxworks
4307 AMD 29000 embedded, using EBMON a29k-none-none
4308 AMD 29000 embedded with COFF a29k-none-coff
4309 AMD 29000 embedded with a.out a29k-none-aout
4311 testsuite/gdb.hp/gdb.threads-hp/ directory
4313 * REMOVED configurations and files
4315 TI TMS320C80 tic80-*-*
4317 PowerPC Solaris powerpcle-*-solaris*
4318 PowerPC Windows NT powerpcle-*-cygwin32
4319 PowerPC Netware powerpc-*-netware*
4320 Harris/CXUX m88k m88*-harris-cxux*
4321 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4322 ns32k-utek-sysv* ns32k-utek-*
4323 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4324 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4325 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4326 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4327 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4329 * Changes to command line processing
4331 The new `--args' feature can be used to specify command-line arguments
4332 for the inferior from gdb's command line.
4334 * Changes to key bindings
4336 There is a new `operate-and-get-next' function bound to `C-o'.
4338 *** Changes in GDB 5.1.1
4340 Fix compile problem on DJGPP.
4342 Fix a problem with floating-point registers on the i386 being
4345 Fix to stop GDB crashing on .debug_str debug info.
4347 Numerous documentation fixes.
4349 Numerous testsuite fixes.
4351 *** Changes in GDB 5.1:
4353 * New native configurations
4355 Alpha FreeBSD alpha*-*-freebsd*
4356 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4357 MIPS GNU/Linux mips*-*-linux*
4358 MIPS SGI Irix 6.x mips*-sgi-irix6*
4359 ia64 AIX ia64-*-aix*
4360 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4364 Motorola 68HC11 and 68HC12 m68hc11-elf
4366 UltraSparc running GNU/Linux sparc64-*-linux*
4368 * OBSOLETE configurations and files
4370 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4371 Harris/CXUX m88k m88*-harris-cxux*
4372 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4373 ns32k-utek-sysv* ns32k-utek-*
4374 TI TMS320C80 tic80-*-*
4376 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4377 PowerPC Solaris powerpcle-*-solaris*
4378 PowerPC Windows NT powerpcle-*-cygwin32
4379 PowerPC Netware powerpc-*-netware*
4380 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4381 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4382 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4383 Apple Macintosh (MPW) host N/A
4385 stuff.c (Program to stuff files into a specially prepared space in kdb)
4386 kdb-start.c (Main loop for the standalone kernel debugger)
4388 Configurations that have been declared obsolete in this release have
4389 been commented out. Unless there is activity to revive these
4390 configurations, the next release of GDB will have their sources
4391 permanently REMOVED.
4393 * REMOVED configurations and files
4395 Altos 3068 m68*-altos-*
4396 Convex c1-*-*, c2-*-*
4398 ARM RISCix arm-*-* (as host)
4402 * GDB has been converted to ISO C.
4404 GDB's source code has been converted to ISO C. In particular, the
4405 sources are fully protoized, and rely on standard headers being
4410 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4412 * The MI enabled by default.
4414 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4415 revised and enabled by default. Packages which use GDB as a debugging
4416 engine behind a UI or another front end are encouraged to switch to
4417 using the GDB/MI interface, instead of the old annotations interface
4418 which is now deprecated.
4420 * Support for debugging Pascal programs.
4422 GDB now includes support for debugging Pascal programs. The following
4423 main features are supported:
4425 - Pascal-specific data types such as sets;
4427 - automatic recognition of Pascal sources based on file-name
4430 - Pascal-style display of data types, variables, and functions;
4432 - a Pascal expression parser.
4434 However, some important features are not yet supported.
4436 - Pascal string operations are not supported at all;
4438 - there are some problems with boolean types;
4440 - Pascal type hexadecimal constants are not supported
4441 because they conflict with the internal variables format;
4443 - support for Pascal objects and classes is not full yet;
4445 - unlike Pascal, GDB is case-sensitive for symbol names.
4447 * Changes in completion.
4449 Commands such as `shell', `run' and `set args', which pass arguments
4450 to inferior programs, now complete on file names, similar to what
4451 users expect at the shell prompt.
4453 Commands which accept locations, such as `disassemble', `print',
4454 `breakpoint', `until', etc. now complete on filenames as well as
4455 program symbols. Thus, if you type "break foob TAB", and the source
4456 files linked into the programs include `foobar.c', that file name will
4457 be one of the candidates for completion. However, file names are not
4458 considered for completion after you typed a colon that delimits a file
4459 name from a name of a function in that file, as in "break foo.c:bar".
4461 `set demangle-style' completes on available demangling styles.
4463 * New platform-independent commands:
4465 It is now possible to define a post-hook for a command as well as a
4466 hook that runs before the command. For more details, see the
4467 documentation of `hookpost' in the GDB manual.
4469 * Changes in GNU/Linux native debugging.
4471 Support for debugging multi-threaded programs has been completely
4472 revised for all platforms except m68k and sparc. You can now debug as
4473 many threads as your system allows you to have.
4475 Attach/detach is supported for multi-threaded programs.
4477 Support for SSE registers was added for x86. This doesn't work for
4478 multi-threaded programs though.
4480 * Changes in MIPS configurations.
4482 Multi-arch support is enabled for all MIPS configurations.
4484 GDB can now be built as native debugger on SGI Irix 6.x systems for
4485 debugging n32 executables. (Debugging 64-bit executables is not yet
4488 * Unified support for hardware watchpoints in all x86 configurations.
4490 Most (if not all) native x86 configurations support hardware-assisted
4491 breakpoints and watchpoints in a unified manner. This support
4492 implements debug register sharing between watchpoints, which allows to
4493 put a virtually infinite number of watchpoints on the same address,
4494 and also supports watching regions up to 16 bytes with several debug
4497 The new maintenance command `maintenance show-debug-regs' toggles
4498 debugging print-outs in functions that insert, remove, and test
4499 watchpoints and hardware breakpoints.
4501 * Changes in the DJGPP native configuration.
4503 New command ``info dos sysinfo'' displays assorted information about
4504 the CPU, OS, memory, and DPMI server.
4506 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4507 display information about segment descriptors stored in GDT, LDT, and
4510 New commands ``info dos pde'' and ``info dos pte'' display entries
4511 from Page Directory and Page Tables (for now works with CWSDPMI only).
4512 New command ``info dos address-pte'' displays the Page Table entry for
4513 a given linear address.
4515 GDB can now pass command lines longer than 126 characters to the
4516 program being debugged (requires an update to the libdbg.a library
4517 which is part of the DJGPP development kit).
4519 DWARF2 debug info is now supported.
4521 It is now possible to `step' and `next' through calls to `longjmp'.
4523 * Changes in documentation.
4525 All GDB documentation was converted to GFDL, the GNU Free
4526 Documentation License.
4528 Tracepoints-related commands are now fully documented in the GDB
4531 TUI, the Text-mode User Interface, is now documented in the manual.
4533 Tracepoints-related commands are now fully documented in the GDB
4536 The "GDB Internals" manual now has an index. It also includes
4537 documentation of `ui_out' functions, GDB coding standards, x86
4538 hardware watchpoints, and memory region attributes.
4540 * GDB's version number moved to ``version.in''
4542 The Makefile variable VERSION has been replaced by the file
4543 ``version.in''. People creating GDB distributions should update the
4544 contents of this file.
4548 GUD support is now a standard part of the EMACS distribution.
4550 *** Changes in GDB 5.0:
4552 * Improved support for debugging FP programs on x86 targets
4554 Unified and much-improved support for debugging floating-point
4555 programs on all x86 targets. In particular, ``info float'' now
4556 displays the FP registers in the same format on all x86 targets, with
4557 greater level of detail.
4559 * Improvements and bugfixes in hardware-assisted watchpoints
4561 It is now possible to watch array elements, struct members, and
4562 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4563 on x86 targets no longer erroneously trigger when the address is
4566 * Improvements in the native DJGPP version of GDB
4568 The distribution now includes all the scripts and auxiliary files
4569 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4570 machines ``out of the box''.
4572 The DJGPP version can now debug programs that use signals. It is
4573 possible to catch signals that happened in the debuggee, deliver
4574 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4575 would kill the program being debugged.) Programs that hook hardware
4576 interrupts (keyboard, timer, etc.) can also be debugged.
4578 It is now possible to debug DJGPP programs that redirect their
4579 standard handles or switch them to raw (as opposed to cooked) mode, or
4580 even close them. The command ``run < foo > bar'' works as expected,
4581 and ``info terminal'' reports useful information about the debuggee's
4582 terminal, including raw/cooked mode, redirection, etc.
4584 The DJGPP version now uses termios functions for console I/O, which
4585 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4588 DOS-style file names with drive letters are now fully supported by
4591 It is now possible to debug DJGPP programs that switch their working
4592 directory. It is also possible to rerun the debuggee any number of
4593 times without restarting GDB; thus, you can use the same setup,
4594 breakpoints, etc. for many debugging sessions.
4596 * New native configurations
4598 ARM GNU/Linux arm*-*-linux*
4599 PowerPC GNU/Linux powerpc-*-linux*
4603 Motorola MCore mcore-*-*
4604 x86 VxWorks i[3456]86-*-vxworks*
4605 PowerPC VxWorks powerpc-*-vxworks*
4606 TI TMS320C80 tic80-*-*
4608 * OBSOLETE configurations
4610 Altos 3068 m68*-altos-*
4611 Convex c1-*-*, c2-*-*
4613 ARM RISCix arm-*-* (as host)
4616 Configurations that have been declared obsolete will be commented out,
4617 but the code will be left in place. If there is no activity to revive
4618 these configurations before the next release of GDB, the sources will
4619 be permanently REMOVED.
4621 * Gould support removed
4623 Support for the Gould PowerNode and NP1 has been removed.
4625 * New features for SVR4
4627 On SVR4 native platforms (such as Solaris), if you attach to a process
4628 without first loading a symbol file, GDB will now attempt to locate and
4629 load symbols from the running process's executable file.
4631 * Many C++ enhancements
4633 C++ support has been greatly improved. Overload resolution now works properly
4634 in almost all cases. RTTI support is on the way.
4636 * Remote targets can connect to a sub-program
4638 A popen(3) style serial-device has been added. This device starts a
4639 sub-process (such as a stand-alone simulator) and then communicates
4640 with that. The sub-program to run is specified using the syntax
4641 ``|<program> <args>'' vis:
4643 (gdb) set remotedebug 1
4644 (gdb) target extended-remote |mn10300-elf-sim program-args
4646 * MIPS 64 remote protocol
4648 A long standing bug in the mips64 remote protocol where by GDB
4649 expected certain 32 bit registers (ex SR) to be transfered as 32
4650 instead of 64 bits has been fixed.
4652 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4653 added to provide backward compatibility with older versions of GDB.
4655 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4657 The command ``set remotebinarydownload'' command has been replaced by
4658 ``set remote X-packet''. Other commands in ``set remote'' family
4659 include ``set remote P-packet''.
4661 * Breakpoint commands accept ranges.
4663 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4664 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4665 ``tracepoint passcount'' also accepts a range of tracepoints.
4667 * ``apropos'' command added.
4669 The ``apropos'' command searches through command names and
4670 documentation strings, printing out matches, making it much easier to
4671 try to find a command that does what you are looking for.
4675 A new machine oriented interface (MI) has been added to GDB. This
4676 interface is designed for debug environments running GDB as a separate
4677 process. This is part of the long term libGDB project. See the
4678 "GDB/MI" chapter of the GDB manual for further information. It can be
4679 enabled by configuring with:
4681 .../configure --enable-gdbmi
4683 *** Changes in GDB-4.18:
4685 * New native configurations
4687 HP-UX 10.20 hppa*-*-hpux10.20
4688 HP-UX 11.x hppa*-*-hpux11.0*
4689 M68K GNU/Linux m68*-*-linux*
4693 Fujitsu FR30 fr30-*-elf*
4694 Intel StrongARM strongarm-*-*
4695 Mitsubishi D30V d30v-*-*
4697 * OBSOLETE configurations
4699 Gould PowerNode, NP1 np1-*-*, pn-*-*
4701 Configurations that have been declared obsolete will be commented out,
4702 but the code will be left in place. If there is no activity to revive
4703 these configurations before the next release of GDB, the sources will
4704 be permanently REMOVED.
4708 As a compatibility experiment, GDB's source files buildsym.h and
4709 buildsym.c have been converted to pure standard C, no longer
4710 containing any K&R compatibility code. We believe that all systems in
4711 use today either come with a standard C compiler, or have a GCC port
4712 available. If this is not true, please report the affected
4713 configuration to bug-gdb@gnu.org immediately. See the README file for
4714 information about getting a standard C compiler if you don't have one
4719 GDB now uses readline 2.2.
4721 * set extension-language
4723 You can now control the mapping between filename extensions and source
4724 languages by using the `set extension-language' command. For instance,
4725 you can ask GDB to treat .c files as C++ by saying
4726 set extension-language .c c++
4727 The command `info extensions' lists all of the recognized extensions
4728 and their associated languages.
4730 * Setting processor type for PowerPC and RS/6000
4732 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4733 you can use the `set processor' command to specify what variant of the
4734 PowerPC family you are debugging. The command
4738 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4739 following PowerPC and RS6000 variants:
4741 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4742 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4744 403GC IBM PowerPC 403GC
4745 505 Motorola PowerPC 505
4746 860 Motorola PowerPC 860 or 850
4747 601 Motorola PowerPC 601
4748 602 Motorola PowerPC 602
4749 603 Motorola/IBM PowerPC 603 or 603e
4750 604 Motorola PowerPC 604 or 604e
4751 750 Motorola/IBM PowerPC 750 or 750
4753 At the moment, this command just tells GDB what to name the
4754 special-purpose processor registers. Since almost all the affected
4755 registers are inaccessible to user-level programs, this command is
4756 only useful for remote debugging in its present form.
4760 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4761 more extensive support for HP-UX. Added features include shared
4762 library support, kernel threads and hardware watchpoints for 11.00,
4763 support for HP's ANSI C and C++ compilers, and a compatibility mode
4764 for xdb and dbx commands.
4768 HP's donation includes the new concept of catchpoints, which is a
4769 generalization of the old catch command. On HP-UX, it is now possible
4770 to catch exec, fork, and vfork, as well as library loading.
4772 This means that the existing catch command has changed; its first
4773 argument now specifies the type of catch to be set up. See the
4774 output of "help catch" for a list of catchpoint types.
4776 * Debugging across forks
4778 On HP-UX, you can choose which process to debug when a fork() happens
4783 HP has donated a curses-based terminal user interface (TUI). To get
4784 it, build with --enable-tui. Although this can be enabled for any
4785 configuration, at present it only works for native HP debugging.
4787 * GDB remote protocol additions
4789 A new protocol packet 'X' that writes binary data is now available.
4790 Default behavior is to try 'X', then drop back to 'M' if the stub
4791 fails to respond. The settable variable `remotebinarydownload'
4792 allows explicit control over the use of 'X'.
4794 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4795 full 64-bit address. The command
4797 set remoteaddresssize 32
4799 can be used to revert to the old behaviour. For existing remote stubs
4800 the change should not be noticed, as the additional address information
4803 In order to assist in debugging stubs, you may use the maintenance
4804 command `packet' to send any text string to the stub. For instance,
4806 maint packet heythere
4808 sends the packet "$heythere#<checksum>". Note that it is very easy to
4809 disrupt a debugging session by sending the wrong packet at the wrong
4812 The compare-sections command allows you to compare section data on the
4813 target to what is in the executable file without uploading or
4814 downloading, by comparing CRC checksums.
4816 * Tracing can collect general expressions
4818 You may now collect general expressions at tracepoints. This requires
4819 further additions to the target-side stub; see tracepoint.c and
4820 doc/agentexpr.texi for further details.
4822 * mask-address variable for Mips
4824 For Mips targets, you may control the zeroing of the upper 32 bits of
4825 a 64-bit address by entering `set mask-address on'. This is mainly
4826 of interest to users of embedded R4xxx and R5xxx processors.
4828 * Higher serial baud rates
4830 GDB's serial code now allows you to specify baud rates 57600, 115200,
4831 230400, and 460800 baud. (Note that your host system may not be able
4832 to achieve all of these rates.)
4836 The i960 configuration now includes an initial implementation of a
4837 builtin simulator, contributed by Jim Wilson.
4840 *** Changes in GDB-4.17:
4842 * New native configurations
4844 Alpha GNU/Linux alpha*-*-linux*
4845 Unixware 2.x i[3456]86-unixware2*
4846 Irix 6.x mips*-sgi-irix6*
4847 PowerPC GNU/Linux powerpc-*-linux*
4848 PowerPC Solaris powerpcle-*-solaris*
4849 Sparc GNU/Linux sparc-*-linux*
4850 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4854 Argonaut Risc Chip (ARC) arc-*-*
4855 Hitachi H8/300S h8300*-*-*
4856 Matsushita MN10200 w/simulator mn10200-*-*
4857 Matsushita MN10300 w/simulator mn10300-*-*
4858 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4859 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4860 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4861 Mitsubishi D10V w/simulator d10v-*-*
4862 Mitsubishi M32R/D w/simulator m32r-*-elf*
4863 Tsqware Sparclet sparclet-*-*
4864 NEC V850 w/simulator v850-*-*
4866 * New debugging protocols
4868 ARM with RDI protocol arm*-*-*
4869 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4870 DDB and LSI variants of PMON protocol mips*-*-*
4871 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4872 PowerPC with SDS protocol powerpc{,le}-*-eabi
4873 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4877 All configurations can now understand and use the DWARF 2 debugging
4878 format. The choice is automatic, if the symbol file contains DWARF 2
4883 GDB now includes basic Java language support. This support is
4884 only useful with Java compilers that produce native machine code.
4886 * solib-absolute-prefix and solib-search-path
4888 For SunOS and SVR4 shared libraries, you may now set the prefix for
4889 loading absolute shared library symbol files, and the search path for
4890 locating non-absolute shared library symbol files.
4892 * Live range splitting
4894 GDB can now effectively debug code for which GCC has performed live
4895 range splitting as part of its optimization. See gdb/doc/LRS for
4896 more details on the expected format of the stabs information.
4900 GDB's support for the GNU Hurd, including thread debugging, has been
4901 updated to work with current versions of the Hurd.
4905 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4906 instruction set. ARM GDB automatically detects when Thumb
4907 instructions are in use, and adjusts disassembly and backtracing
4912 GDB's MIPS target configurations now handle the MIP16 16-bit
4917 GDB now includes support for overlays; if an executable has been
4918 linked such that multiple sections are based at the same address, GDB
4919 will decide which section to use for symbolic info. You can choose to
4920 control the decision manually, using overlay commands, or implement
4921 additional target-side support and use "overlay load-target" to bring
4922 in the overlay mapping. Do "help overlay" for more detail.
4926 The command "info symbol <address>" displays information about
4927 the symbol at the specified address.
4931 The standard remote protocol now includes an extension that allows
4932 asynchronous collection and display of trace data. This requires
4933 extensive support in the target-side debugging stub. Tracing mode
4934 includes a new interaction mode in GDB and new commands: see the
4935 file tracepoint.c for more details.
4939 Configurations for embedded MIPS now include a simulator contributed
4940 by Cygnus Solutions. The simulator supports the instruction sets
4941 of most MIPS variants.
4945 Sparc configurations may now include the ERC32 simulator contributed
4946 by the European Space Agency. The simulator is not built into
4947 Sparc targets by default; configure with --enable-sim to include it.
4951 For target configurations that may include multiple variants of a
4952 basic architecture (such as MIPS and SH), you may now set the
4953 architecture explicitly. "set arch" sets, "info arch" lists
4954 the possible architectures.
4956 *** Changes in GDB-4.16:
4958 * New native configurations
4960 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4961 M68K NetBSD m68k-*-netbsd*
4962 PowerPC AIX 4.x powerpc-*-aix*
4963 PowerPC MacOS powerpc-*-macos*
4964 PowerPC Windows NT powerpcle-*-cygwin32
4965 RS/6000 AIX 4.x rs6000-*-aix4*
4969 ARM with RDP protocol arm-*-*
4970 I960 with MON960 i960-*-coff
4971 MIPS VxWorks mips*-*-vxworks*
4972 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4973 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4975 Matra Sparclet sparclet-*-*
4979 The powerpc-eabi configuration now includes the PSIM simulator,
4980 contributed by Andrew Cagney, with assistance from Mike Meissner.
4981 PSIM is a very elaborate model of the PowerPC, including not only
4982 basic instruction set execution, but also details of execution unit
4983 performance and I/O hardware. See sim/ppc/README for more details.
4987 GDB now works with Solaris 2.5.
4989 * Windows 95/NT native
4991 GDB will now work as a native debugger on Windows 95 and Windows NT.
4992 To build it from source, you must use the "gnu-win32" environment,
4993 which uses a DLL to emulate enough of Unix to run the GNU tools.
4994 Further information, binaries, and sources are available at
4995 ftp.cygnus.com, under pub/gnu-win32.
4997 * dont-repeat command
4999 If a user-defined command includes the command `dont-repeat', then the
5000 command will not be repeated if the user just types return. This is
5001 useful if the command is time-consuming to run, so that accidental
5002 extra keystrokes don't run the same command many times.
5004 * Send break instead of ^C
5006 The standard remote protocol now includes an option to send a break
5007 rather than a ^C to the target in order to interrupt it. By default,
5008 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5010 * Remote protocol timeout
5012 The standard remote protocol includes a new variable `remotetimeout'
5013 that allows you to set the number of seconds before GDB gives up trying
5014 to read from the target. The default value is 2.
5016 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5018 By default GDB will automatically keep track of objects as they are
5019 loaded and unloaded by the dynamic linker. By using the command `set
5020 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5021 when shared library events occur, thus allowing you to set breakpoints
5022 in shared libraries which are explicitly loaded by the inferior.
5024 Note this feature does not work on hpux8. On hpux9 you must link
5025 /usr/lib/end.o into your program. This feature should work
5026 automatically on hpux10.
5028 * Irix 5.x hardware watchpoint support
5030 Irix 5 configurations now support the use of hardware watchpoints.
5032 * Mips protocol "SYN garbage limit"
5034 When debugging a Mips target using the `target mips' protocol, you
5035 may set the number of characters that GDB will ignore by setting
5036 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5037 every character. The default value is 1050.
5039 * Recording and replaying remote debug sessions
5041 If you set `remotelogfile' to the name of a file, gdb will write to it
5042 a recording of a remote debug session. This recording may then be
5043 replayed back to gdb using "gdbreplay". See gdbserver/README for
5044 details. This is useful when you have a problem with GDB while doing
5045 remote debugging; you can make a recording of the session and send it
5046 to someone else, who can then recreate the problem.
5048 * Speedups for remote debugging
5050 GDB includes speedups for downloading and stepping MIPS systems using
5051 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5052 and more efficient S-record downloading.
5054 * Memory use reductions and statistics collection
5056 GDB now uses less memory and reports statistics about memory usage.
5057 Try the `maint print statistics' command, for example.
5059 *** Changes in GDB-4.15:
5061 * Psymtabs for XCOFF
5063 The symbol reader for AIX GDB now uses partial symbol tables. This
5064 can greatly improve startup time, especially for large executables.
5066 * Remote targets use caching
5068 Remote targets now use a data cache to speed up communication with the
5069 remote side. The data cache could lead to incorrect results because
5070 it doesn't know about volatile variables, thus making it impossible to
5071 debug targets which use memory mapped I/O devices. `set remotecache
5072 off' turns the the data cache off.
5074 * Remote targets may have threads
5076 The standard remote protocol now includes support for multiple threads
5077 in the target system, using new protocol commands 'H' and 'T'. See
5078 gdb/remote.c for details.
5082 If GDB is configured with `--enable-netrom', then it will include
5083 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5084 acts as though it is a bank of ROM on the target board, but you can
5085 write into it over the network. GDB's support consists only of
5086 support for fast loading into the emulated ROM; to debug, you must use
5087 another protocol, such as standard remote protocol. The usual
5088 sequence is something like
5090 target nrom <netrom-hostname>
5092 target remote <netrom-hostname>:1235
5096 GDB now includes support for the Apple Macintosh, as a host only. It
5097 may be run as either an MPW tool or as a standalone application, and
5098 it can debug through the serial port. All the usual GDB commands are
5099 available, but to the target command, you must supply "serial" as the
5100 device type instead of "/dev/ttyXX". See mpw-README in the main
5101 directory for more information on how to build. The MPW configuration
5102 scripts */mpw-config.in support only a few targets, and only the
5103 mips-idt-ecoff target has been tested.
5107 GDB configuration now uses autoconf. This is not user-visible,
5108 but does simplify configuration and building.
5112 GDB now supports hpux10.
5114 *** Changes in GDB-4.14:
5116 * New native configurations
5118 x86 FreeBSD i[345]86-*-freebsd
5119 x86 NetBSD i[345]86-*-netbsd
5120 NS32k NetBSD ns32k-*-netbsd
5121 Sparc NetBSD sparc-*-netbsd
5125 A29K VxWorks a29k-*-vxworks
5126 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5127 CPU32 EST-300 emulator m68*-*-est*
5128 PowerPC ELF powerpc-*-elf
5131 * Alpha OSF/1 support for procfs
5133 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5134 possible to attach to running processes. As the mounting of the /proc
5135 filesystem is optional on the Alpha, GDB automatically determines
5136 the availability of /proc during startup. This can lead to problems
5137 if /proc is unmounted after GDB has been started.
5139 * Arguments to user-defined commands
5141 User commands may accept up to 10 arguments separated by whitespace.
5142 Arguments are accessed within the user command via $arg0..$arg9. A
5145 print $arg0 + $arg1 + $arg2
5147 To execute the command use:
5150 Defines the command "adder" which prints the sum of its three arguments.
5151 Note the arguments are text substitutions, so they may reference variables,
5152 use complex expressions, or even perform inferior function calls.
5154 * New `if' and `while' commands
5156 This makes it possible to write more sophisticated user-defined
5157 commands. Both commands take a single argument, which is the
5158 expression to evaluate, and must be followed by the commands to
5159 execute, one per line, if the expression is nonzero, the list being
5160 terminated by the word `end'. The `if' command list may include an
5161 `else' word, which causes the following commands to be executed only
5162 if the expression is zero.
5164 * Fortran source language mode
5166 GDB now includes partial support for Fortran 77. It will recognize
5167 Fortran programs and can evaluate a subset of Fortran expressions, but
5168 variables and functions may not be handled correctly. GDB will work
5169 with G77, but does not yet know much about symbols emitted by other
5172 * Better HPUX support
5174 Most debugging facilities now work on dynamic executables for HPPAs
5175 running hpux9 or later. You can attach to running dynamically linked
5176 processes, but by default the dynamic libraries will be read-only, so
5177 for instance you won't be able to put breakpoints in them. To change
5178 that behavior do the following before running the program:
5184 This will cause the libraries to be mapped private and read-write.
5185 To revert to the normal behavior, do this:
5191 You cannot set breakpoints or examine data in the library until after
5192 the library is loaded if the function/data symbols do not have
5195 GDB can now also read debug symbols produced by the HP C compiler on
5196 HPPAs (sorry, no C++, Fortran or 68k support).
5198 * Target byte order now dynamically selectable
5200 You can choose which byte order to use with a target system, via the
5201 commands "set endian big" and "set endian little", and you can see the
5202 current setting by using "show endian". You can also give the command
5203 "set endian auto", in which case GDB will use the byte order
5204 associated with the executable. Currently, only embedded MIPS
5205 configurations support dynamic selection of target byte order.
5207 * New DOS host serial code
5209 This version uses DPMI interrupts to handle buffered I/O, so you
5210 no longer need to run asynctsr when debugging boards connected to
5213 *** Changes in GDB-4.13:
5215 * New "complete" command
5217 This lists all the possible completions for the rest of the line, if it
5218 were to be given as a command itself. This is intended for use by emacs.
5220 * Trailing space optional in prompt
5222 "set prompt" no longer adds a space for you after the prompt you set. This
5223 allows you to set a prompt which ends in a space or one that does not.
5225 * Breakpoint hit counts
5227 "info break" now displays a count of the number of times the breakpoint
5228 has been hit. This is especially useful in conjunction with "ignore"; you
5229 can ignore a large number of breakpoint hits, look at the breakpoint info
5230 to see how many times the breakpoint was hit, then run again, ignoring one
5231 less than that number, and this will get you quickly to the last hit of
5234 * Ability to stop printing at NULL character
5236 "set print null-stop" will cause GDB to stop printing the characters of
5237 an array when the first NULL is encountered. This is useful when large
5238 arrays actually contain only short strings.
5240 * Shared library breakpoints
5242 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5243 breakpoints in shared libraries before the executable is run.
5245 * Hardware watchpoints
5247 There is a new hardware breakpoint for the watch command for sparclite
5248 targets. See gdb/sparclite/hw_breakpoint.note.
5250 Hardware watchpoints are also now supported under GNU/Linux.
5254 Annotations have been added. These are for use with graphical interfaces,
5255 and are still experimental. Currently only gdba.el uses these.
5257 * Improved Irix 5 support
5259 GDB now works properly with Irix 5.2.
5261 * Improved HPPA support
5263 GDB now works properly with the latest GCC and GAS.
5265 * New native configurations
5267 Sequent PTX4 i[34]86-sequent-ptx4
5268 HPPA running OSF/1 hppa*-*-osf*
5269 Atari TT running SVR4 m68*-*-sysv4*
5270 RS/6000 LynxOS rs6000-*-lynxos*
5274 OS/9000 i[34]86-*-os9k
5275 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5278 * Hitachi SH7000 and E7000-PC ICE support
5280 There is now support for communicating with the Hitachi E7000-PC ICE.
5281 This is available automatically when GDB is configured for the SH.
5285 As usual, a variety of small fixes and improvements, both generic
5286 and configuration-specific. See the ChangeLog for more detail.
5288 *** Changes in GDB-4.12:
5290 * Irix 5 is now supported
5294 GDB-4.12 on the HPPA has a number of changes which make it unable
5295 to debug the output from the currently released versions of GCC and
5296 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5297 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5298 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5301 *** Changes in GDB-4.11:
5303 * User visible changes:
5307 The "set remotedebug" option is now consistent between the mips remote
5308 target, remote targets using the gdb-specific protocol, UDI (AMD's
5309 debug protocol for the 29k) and the 88k bug monitor. It is now an
5310 integer specifying a debug level (normally 0 or 1, but 2 means more
5311 debugging info for the mips target).
5313 * DEC Alpha native support
5315 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5316 debug info, but GDB works fairly well with the DEC compiler and should
5317 work with a future GCC release. See the README file for a few
5318 Alpha-specific notes.
5320 * Preliminary thread implementation
5322 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5324 * LynxOS native and target support for 386
5326 This release has been hosted on LynxOS 2.2, and also can be configured
5327 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5330 * Improvements in C++ mangling/demangling.
5332 This release has much better g++ debugging, specifically in name
5333 mangling/demangling, virtual function calls, print virtual table,
5334 call methods, ...etc.
5336 *** Changes in GDB-4.10:
5338 * User visible changes:
5340 Remote debugging using the GDB-specific (`target remote') protocol now
5341 supports the `load' command. This is only useful if you have some
5342 other way of getting the stub to the target system, and you can put it
5343 somewhere in memory where it won't get clobbered by the download.
5345 Filename completion now works.
5347 When run under emacs mode, the "info line" command now causes the
5348 arrow to point to the line specified. Also, "info line" prints
5349 addresses in symbolic form (as well as hex).
5351 All vxworks based targets now support a user settable option, called
5352 vxworks-timeout. This option represents the number of seconds gdb
5353 should wait for responses to rpc's. You might want to use this if
5354 your vxworks target is, perhaps, a slow software simulator or happens
5355 to be on the far side of a thin network line.
5359 This release contains support for using a DEC alpha as a GDB host for
5360 cross debugging. Native alpha debugging is not supported yet.
5363 *** Changes in GDB-4.9:
5367 This is the first GDB release which is accompanied by a matching testsuite.
5368 The testsuite requires installation of dejagnu, which should be available
5369 via ftp from most sites that carry GNU software.
5373 'Cfront' style demangling has had its name changed to 'ARM' style, to
5374 emphasize that it was written from the specifications in the C++ Annotated
5375 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5376 disclaimers, it still generated too much confusion with users attempting to
5377 use gdb with AT&T cfront.
5381 GDB now uses a standard remote interface to a simulator library.
5382 So far, the library contains simulators for the Zilog Z8001/2, the
5383 Hitachi H8/300, H8/500 and Super-H.
5385 * New targets supported
5387 H8/300 simulator h8300-hitachi-hms or h8300hms
5388 H8/500 simulator h8500-hitachi-hms or h8500hms
5389 SH simulator sh-hitachi-hms or sh
5390 Z8000 simulator z8k-zilog-none or z8ksim
5391 IDT MIPS board over serial line mips-idt-ecoff
5393 Cross-debugging to GO32 targets is supported. It requires a custom
5394 version of the i386-stub.c module which is integrated with the
5395 GO32 memory extender.
5397 * New remote protocols
5399 MIPS remote debugging protocol.
5401 * New source languages supported
5403 This version includes preliminary support for Chill, a Pascal like language
5404 used by telecommunications companies. Chill support is also being integrated
5405 into the GNU compiler, but we don't know when it will be publically available.
5408 *** Changes in GDB-4.8:
5410 * HP Precision Architecture supported
5412 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5413 version of this support was available as a set of patches from the
5414 University of Utah. GDB does not support debugging of programs
5415 compiled with the HP compiler, because HP will not document their file
5416 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5417 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5419 Many problems in the preliminary version have been fixed.
5421 * Faster and better demangling
5423 We have improved template demangling and fixed numerous bugs in the GNU style
5424 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5425 character types (wchar_t) are now supported. Demangling of each symbol is now
5426 only done once, and is cached when the symbol table for a file is read in.
5427 This results in a small increase in memory usage for C programs, a moderate
5428 increase in memory usage for C++ programs, and a fantastic speedup in
5431 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5432 from the specifications in the Annotated Reference Manual, which AT&T's
5433 compiler does not actually implement.
5435 * G++ multiple inheritance compiler problem
5437 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5438 inheritance lattices was reworked to properly discover ambiguities. We
5439 recently found an example which causes this new algorithm to fail in a
5440 very subtle way, producing bad debug information for those classes.
5441 The file 'gcc.patch' (in this directory) can be applied to gcc to
5442 circumvent the problem. A future GCC release will contain a complete
5445 The previous G++ debug info problem (mentioned below for the gdb-4.7
5446 release) is fixed in gcc version 2.3.2.
5448 * Improved configure script
5450 The `configure' script will now attempt to guess your system type if
5451 you don't supply a host system type. The old scheme of supplying a
5452 host system triplet is preferable over using this. All the magic is
5453 done in the new `config.guess' script. Examine it for details.
5455 We have also brought our configure script much more in line with the FSF's
5456 version. It now supports the --with-xxx options. In particular,
5457 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5458 The resulting GDB will not be able to read arbitrary object file formats --
5459 only the format ``expected'' to be used on the configured target system.
5460 We hope to make this the default in a future release.
5462 * Documentation improvements
5464 There's new internal documentation on how to modify GDB, and how to
5465 produce clean changes to the code. We implore people to read it
5466 before submitting changes.
5468 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5469 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5470 `info' files are also provided. To build `info' files from scratch,
5471 you will need the latest `makeinfo' release, which will be available in
5472 a future texinfo-X.Y release.
5474 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5475 We're not sure exactly which versions have this problem, but it has
5476 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5477 or better. If that isn't possible, there is a patch in
5478 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5479 around this problem.
5483 GDB now supports array constants that can be used in expressions typed in by
5484 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5485 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5488 The new directory `gdb/sparclite' contains a program that demonstrates
5489 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5491 * New native hosts supported
5493 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5494 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5496 * New targets supported
5498 AMD 29k family via UDI a29k-amd-udi or udi29k
5500 * New file formats supported
5502 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5503 HPUX core files, and SCO 3.2v2 core files.
5507 Attaching to processes now works again; thanks for the many bug reports.
5509 We have also stomped on a bunch of core dumps caused by
5510 printf_filtered("%s") problems.
5512 We eliminated a copyright problem on the rpc and ptrace header files
5513 for VxWorks, which was discovered at the last minute during the 4.7
5514 release. You should now be able to build a VxWorks GDB.
5516 You can now interrupt gdb while an attached process is running. This
5517 will cause the attached process to stop, and give control back to GDB.
5519 We fixed problems caused by using too many file descriptors
5520 for reading symbols from object files and libraries. This was
5521 especially a problem for programs that used many (~100) shared
5524 The `step' command now only enters a subroutine if there is line number
5525 information for the subroutine. Otherwise it acts like the `next'
5526 command. Previously, `step' would enter subroutines if there was
5527 any debugging information about the routine. This avoids problems
5528 when using `cc -g1' on MIPS machines.
5530 * Internal improvements
5532 GDB's internal interfaces have been improved to make it easier to support
5533 debugging of multiple languages in the future.
5535 GDB now uses a common structure for symbol information internally.
5536 Minimal symbols (derived from linkage symbols in object files), partial
5537 symbols (from a quick scan of debug information), and full symbols
5538 contain a common subset of information, making it easier to write
5539 shared code that handles any of them.
5541 * New command line options
5543 We now accept --silent as an alias for --quiet.
5547 The memory-mapped-malloc library is now licensed under the GNU Library
5548 General Public License.
5550 *** Changes in GDB-4.7:
5552 * Host/native/target split
5554 GDB has had some major internal surgery to untangle the support for
5555 hosts and remote targets. Now, when you configure GDB for a remote
5556 target, it will no longer load in all of the support for debugging
5557 local programs on the host. When fully completed and tested, this will
5558 ensure that arbitrary host/target combinations are possible.
5560 The primary conceptual shift is to separate the non-portable code in
5561 GDB into three categories. Host specific code is required any time GDB
5562 is compiled on that host, regardless of the target. Target specific
5563 code relates to the peculiarities of the target, but can be compiled on
5564 any host. Native specific code is everything else: it can only be
5565 built when the host and target are the same system. Child process
5566 handling and core file support are two common `native' examples.
5568 GDB's use of /proc for controlling Unix child processes is now cleaner.
5569 It has been split out into a single module under the `target_ops' vector,
5570 plus two native-dependent functions for each system that uses /proc.
5572 * New hosts supported
5574 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5575 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5576 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5578 * New targets supported
5580 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5581 68030 and CPU32 m68030-*-*, m68332-*-*
5583 * New native hosts supported
5585 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5586 (386bsd is not well tested yet)
5587 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5589 * New file formats supported
5591 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5592 supports reading of `a.out.adobe' object files, which are an a.out
5593 format extended with minimal information about multiple sections.
5597 `show copying' is the same as the old `info copying'.
5598 `show warranty' is the same as `info warrantee'.
5599 These were renamed for consistency. The old commands continue to work.
5601 `info handle' is a new alias for `info signals'.
5603 You can now define pre-command hooks, which attach arbitrary command
5604 scripts to any command. The commands in the hook will be executed
5605 prior to the user's command. You can also create a hook which will be
5606 executed whenever the program stops. See gdb.texinfo.
5610 We now deal with Cfront style name mangling, and can even extract type
5611 info from mangled symbols. GDB can automatically figure out which
5612 symbol mangling style your C++ compiler uses.
5614 Calling of methods and virtual functions has been improved as well.
5618 The crash that occured when debugging Sun Ansi-C compiled binaries is
5619 fixed. This was due to mishandling of the extra N_SO stabs output
5622 We also finally got Ultrix 4.2 running in house, and fixed core file
5623 support, with help from a dozen people on the net.
5625 John M. Farrell discovered that the reason that single-stepping was so
5626 slow on all of the Mips based platforms (primarily SGI and DEC) was
5627 that we were trying to demangle and lookup a symbol used for internal
5628 purposes on every instruction that was being stepped through. Changing
5629 the name of that symbol so that it couldn't be mistaken for a C++
5630 mangled symbol sped things up a great deal.
5632 Rich Pixley sped up symbol lookups in general by getting much smarter
5633 about when C++ symbol mangling is necessary. This should make symbol
5634 completion (TAB on the command line) much faster. It's not as fast as
5635 we'd like, but it's significantly faster than gdb-4.6.
5639 A new user controllable variable 'call_scratch_address' can
5640 specify the location of a scratch area to be used when GDB
5641 calls a function in the target. This is necessary because the
5642 usual method of putting the scratch area on the stack does not work
5643 in systems that have separate instruction and data spaces.
5645 We integrated changes to support the 29k UDI (Universal Debugger
5646 Interface), but discovered at the last minute that we didn't have all
5647 of the appropriate copyright paperwork. We are working with AMD to
5648 resolve this, and hope to have it available soon.
5652 We have sped up the remote serial line protocol, especially for targets
5653 with lots of registers. It now supports a new `expedited status' ('T')
5654 message which can be used in place of the existing 'S' status message.
5655 This allows the remote stub to send only the registers that GDB
5656 needs to make a quick decision about single-stepping or conditional
5657 breakpoints, eliminating the need to fetch the entire register set for
5658 each instruction being stepped through.
5660 The GDB remote serial protocol now implements a write-through cache for
5661 registers, only re-reading the registers if the target has run.
5663 There is also a new remote serial stub for SPARC processors. You can
5664 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5665 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5666 processor with a serial port.
5670 Configure.in files have become much easier to read and modify. A new
5671 `table driven' format makes it more obvious what configurations are
5672 supported, and what files each one uses.
5676 There is a new opcodes library which will eventually contain all of the
5677 disassembly routines and opcode tables. At present, it only contains
5678 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5679 disassembler (binutils/objdump) to share these routines.
5681 The libiberty library is now copylefted under the GNU Library General
5682 Public License. This allows more liberal use, and was done so libg++
5683 can use it. This makes no difference to GDB, since the Library License
5684 grants all the rights from the General Public License.
5688 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5689 reference to the stabs symbol info used by the debugger. It is (as far
5690 as we know) the only published document on this fascinating topic. We
5691 encourage you to read it, compare it to the stabs information on your
5692 system, and send improvements on the document in general (to
5693 bug-gdb@prep.ai.mit.edu).
5695 And, of course, many bugs have been fixed.
5698 *** Changes in GDB-4.6:
5700 * Better support for C++ function names
5702 GDB now accepts as input the "demangled form" of C++ overloaded function
5703 names and member function names, and can do command completion on such names
5704 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5705 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5706 Make use of command completion, it is your friend.
5708 GDB also now accepts a variety of C++ mangled symbol formats. They are
5709 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5710 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5711 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5712 for the list of formats.
5714 * G++ symbol mangling problem
5716 Recent versions of gcc have a bug in how they emit debugging information for
5717 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5718 directory) can be applied to gcc to fix the problem. Alternatively, if you
5719 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5720 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5721 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5724 * New 'maintenance' command
5726 All of the commands related to hacking GDB internals have been moved out of
5727 the main command set, and now live behind the 'maintenance' command. This
5728 can also be abbreviated as 'mt'. The following changes were made:
5730 dump-me -> maintenance dump-me
5731 info all-breakpoints -> maintenance info breakpoints
5732 printmsyms -> maintenance print msyms
5733 printobjfiles -> maintenance print objfiles
5734 printpsyms -> maintenance print psymbols
5735 printsyms -> maintenance print symbols
5737 The following commands are new:
5739 maintenance demangle Call internal GDB demangler routine to
5740 demangle a C++ link name and prints the result.
5741 maintenance print type Print a type chain for a given symbol
5743 * Change to .gdbinit file processing
5745 We now read the $HOME/.gdbinit file before processing the argv arguments
5746 (e.g. reading symbol files or core files). This allows global parameters to
5747 be set, which will apply during the symbol reading. The ./.gdbinit is still
5748 read after argv processing.
5750 * New hosts supported
5752 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5754 GNU/Linux support i386-unknown-linux or linux
5756 We are also including code to support the HP/PA running BSD and HPUX. This
5757 is almost guaranteed not to work, as we didn't have time to test or build it
5758 for this release. We are including it so that the more adventurous (or
5759 masochistic) of you can play with it. We also had major problems with the
5760 fact that the compiler that we got from HP doesn't support the -g option.
5763 * New targets supported
5765 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5767 * More smarts about finding #include files
5769 GDB now remembers the compilation directory for all include files, and for
5770 all files from which C is generated (like yacc and lex sources). This
5771 greatly improves GDB's ability to find yacc/lex sources, and include files,
5772 especially if you are debugging your program from a directory different from
5773 the one that contains your sources.
5775 We also fixed a bug which caused difficulty with listing and setting
5776 breakpoints in include files which contain C code. (In the past, you had to
5777 try twice in order to list an include file that you hadn't looked at before.)
5779 * Interesting infernals change
5781 GDB now deals with arbitrary numbers of sections, where the symbols for each
5782 section must be relocated relative to that section's landing place in the
5783 target's address space. This work was needed to support ELF with embedded
5784 stabs used by Solaris-2.0.
5786 * Bug fixes (of course!)
5788 There have been loads of fixes for the following things:
5789 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5790 i960, stabs, DOS(GO32), procfs, etc...
5792 See the ChangeLog for details.
5794 *** Changes in GDB-4.5:
5796 * New machines supported (host and target)
5798 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5800 SGI Irix-4.x mips-sgi-irix4 or iris4
5802 * New malloc package
5804 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5805 Mmalloc is capable of handling mutiple heaps of memory. It is also
5806 capable of saving a heap to a file, and then mapping it back in later.
5807 This can be used to greatly speedup the startup of GDB by using a
5808 pre-parsed symbol table which lives in a mmalloc managed heap. For
5809 more details, please read mmalloc/mmalloc.texi.
5813 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5814 'help info proc' for details.
5816 * MIPS ecoff symbol table format
5818 The code that reads MIPS symbol table format is now supported on all hosts.
5819 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5822 * File name changes for MS-DOS
5824 Many files in the config directories have been renamed to make it easier to
5825 support GDB on MS-DOSe systems (which have very restrictive file name
5826 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5827 environment) is close to working but has some remaining problems. Note
5828 that debugging of DOS programs is not supported, due to limitations
5829 in the ``operating system'', but it can be used to host cross-debugging.
5831 * Cross byte order fixes
5833 Many fixes have been made to support cross debugging of Sparc and MIPS
5834 targets from hosts whose byte order differs.
5836 * New -mapped and -readnow options
5838 If memory-mapped files are available on your system through the 'mmap'
5839 system call, you can use the -mapped option on the `file' or
5840 `symbol-file' commands to cause GDB to write the symbols from your
5841 program into a reusable file. If the program you are debugging is
5842 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5843 Future GDB debugging sessions will notice the presence of this file,
5844 and will quickly map in symbol information from it, rather than reading
5845 the symbol table from the executable program. Using the '-mapped'
5846 option in a GDB `file' or `symbol-file' command has the same effect as
5847 starting GDB with the '-mapped' command-line option.
5849 You can cause GDB to read the entire symbol table immediately by using
5850 the '-readnow' option with any of the commands that load symbol table
5851 information (or on the GDB command line). This makes the command
5852 slower, but makes future operations faster.
5854 The -mapped and -readnow options are typically combined in order to
5855 build a `fred.syms' file that contains complete symbol information.
5856 A simple GDB invocation to do nothing but build a `.syms' file for future
5859 gdb -batch -nx -mapped -readnow programname
5861 The `.syms' file is specific to the host machine on which GDB is run.
5862 It holds an exact image of GDB's internal symbol table. It cannot be
5863 shared across multiple host platforms.
5865 * longjmp() handling
5867 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5868 siglongjmp() without losing control. This feature has not yet been ported to
5869 all systems. It currently works on many 386 platforms, all MIPS-based
5870 platforms (SGI, DECstation, etc), and Sun3/4.
5874 Preliminary work has been put in to support the new Solaris OS from Sun. At
5875 this time, it can control and debug processes, but it is not capable of
5880 As always, many many bug fixes. The major areas were with g++, and mipsread.
5881 People using the MIPS-based platforms should experience fewer mysterious
5882 crashes and trashed symbol tables.
5884 *** Changes in GDB-4.4:
5886 * New machines supported (host and target)
5888 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5890 BSD Reno on Vax vax-dec-bsd
5891 Ultrix on Vax vax-dec-ultrix
5893 * New machines supported (target)
5895 AMD 29000 embedded, using EBMON a29k-none-none
5899 GDB continues to improve its handling of C++. `References' work better.
5900 The demangler has also been improved, and now deals with symbols mangled as
5901 per the Annotated C++ Reference Guide.
5903 GDB also now handles `stabs' symbol information embedded in MIPS
5904 `ecoff' symbol tables. Since the ecoff format was not easily
5905 extensible to handle new languages such as C++, this appeared to be a
5906 good way to put C++ debugging info into MIPS binaries. This option
5907 will be supported in the GNU C compiler, version 2, when it is
5910 * New features for SVR4
5912 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5913 shared libraries. Debugging dynamically linked programs should present
5914 only minor differences from debugging statically linked programs.
5916 The `info proc' command will print out information about any process
5917 on an SVR4 system (including the one you are debugging). At the moment,
5918 it prints the address mappings of the process.
5920 If you bring up GDB on another SVR4 system, please send mail to
5921 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5923 * Better dynamic linking support in SunOS
5925 Reading symbols from shared libraries which contain debugging symbols
5926 now works properly. However, there remain issues such as automatic
5927 skipping of `transfer vector' code during function calls, which
5928 make it harder to debug code in a shared library, than to debug the
5929 same code linked statically.
5933 GDB is now using the latest `getopt' routines from the FSF. This
5934 version accepts the -- prefix for options with long names. GDB will
5935 continue to accept the old forms (-option and +option) as well.
5936 Various single letter abbreviations for options have been explicity
5937 added to the option table so that they won't get overshadowed in the
5938 future by other options that begin with the same letter.
5942 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5943 Many assorted bugs have been handled. Many more remain to be handled.
5944 See the various ChangeLog files (primarily in gdb and bfd) for details.
5947 *** Changes in GDB-4.3:
5949 * New machines supported (host and target)
5951 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5952 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5953 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5955 * Almost SCO Unix support
5957 We had hoped to support:
5958 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5959 (except for core file support), but we discovered very late in the release
5960 that it has problems with process groups that render gdb unusable. Sorry
5961 about that. I encourage people to fix it and post the fixes.
5963 * Preliminary ELF and DWARF support
5965 GDB can read ELF object files on System V Release 4, and can handle
5966 debugging records for C, in DWARF format, in ELF files. This support
5967 is preliminary. If you bring up GDB on another SVR4 system, please
5968 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5973 GDB now uses the latest `readline' library. One user-visible change
5974 is that two tabs will list possible command completions, which previously
5975 required typing M-? (meta-question mark, or ESC ?).
5979 The `stepi' bug that many of you noticed has been squashed.
5980 Many bugs in C++ have been handled. Many more remain to be handled.
5981 See the various ChangeLog files (primarily in gdb and bfd) for details.
5983 * State of the MIPS world (in case you wondered):
5985 GDB can understand the symbol tables emitted by the compilers
5986 supplied by most vendors of MIPS-based machines, including DEC. These
5987 symbol tables are in a format that essentially nobody else uses.
5989 Some versions of gcc come with an assembler post-processor called
5990 mips-tfile. This program is required if you want to do source-level
5991 debugging of gcc-compiled programs. I believe FSF does not ship
5992 mips-tfile with gcc version 1, but it will eventually come with gcc
5995 Debugging of g++ output remains a problem. g++ version 1.xx does not
5996 really support it at all. (If you're lucky, you should be able to get
5997 line numbers and stack traces to work, but no parameters or local
5998 variables.) With some work it should be possible to improve the
6001 When gcc version 2 is released, you will have somewhat better luck.
6002 However, even then you will get confusing results for inheritance and
6005 We will eventually provide full debugging of g++ output on
6006 DECstations. This will probably involve some kind of stabs-in-ecoff
6007 encapulation, but the details have not been worked out yet.
6010 *** Changes in GDB-4.2:
6012 * Improved configuration
6014 Only one copy of `configure' exists now, and it is not self-modifying.
6015 Porting BFD is simpler.
6019 The `step' and `next' commands now only stop at the first instruction
6020 of a source line. This prevents the multiple stops that used to occur
6021 in switch statements, for-loops, etc. `Step' continues to stop if a
6022 function that has debugging information is called within the line.
6026 Lots of small bugs fixed. More remain.
6028 * New host supported (not target)
6030 Intel 386 PC clone running Mach i386-none-mach
6033 *** Changes in GDB-4.1:
6035 * Multiple source language support
6037 GDB now has internal scaffolding to handle several source languages.
6038 It determines the type of each source file from its filename extension,
6039 and will switch expression parsing and number formatting to match the
6040 language of the function in the currently selected stack frame.
6041 You can also specifically set the language to be used, with
6042 `set language c' or `set language modula-2'.
6046 GDB now has preliminary support for the GNU Modula-2 compiler,
6047 currently under development at the State University of New York at
6048 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6049 continue through the fall of 1991 and into 1992.
6051 Other Modula-2 compilers are currently not supported, and attempting to
6052 debug programs compiled with them will likely result in an error as the
6053 symbol table is read. Feel free to work on it, though!
6055 There are hooks in GDB for strict type checking and range checking,
6056 in the `Modula-2 philosophy', but they do not currently work.
6060 GDB can now write to executable and core files (e.g. patch
6061 a variable's value). You must turn this switch on, specify
6062 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6063 by assigning a new value to a variable. Modifications take
6066 * Automatic SunOS shared library reading
6068 When you run your program, GDB automatically determines where its
6069 shared libraries (if any) have been loaded, and reads their symbols.
6070 The `share' command is no longer needed. This also works when
6071 examining core files.
6075 You can specify the number of lines that the `list' command shows.
6078 * New machines supported (host and target)
6080 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6081 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6082 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6084 * New hosts supported (not targets)
6086 IBM RT/PC: romp-ibm-aix or rtpc
6088 * New targets supported (not hosts)
6090 AMD 29000 embedded with COFF a29k-none-coff
6091 AMD 29000 embedded with a.out a29k-none-aout
6092 Ultracomputer remote kernel debug a29k-nyu-kern
6094 * New remote interfaces
6100 *** Changes in GDB-4.0:
6104 Wide output is wrapped at good places to make the output more readable.
6106 Gdb now supports cross-debugging from a host machine of one type to a
6107 target machine of another type. Communication with the target system
6108 is over serial lines. The ``target'' command handles connecting to the
6109 remote system; the ``load'' command will download a program into the
6110 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6111 also supports debugging of realtime processes running under VxWorks,
6112 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6113 stub on the target system.
6115 New CPUs supported include the AMD 29000 and Intel 960.
6117 GDB now reads object files and symbol tables via a ``binary file''
6118 library, which allows a single copy of GDB to debug programs of multiple
6119 object file types such as a.out and coff.
6121 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6122 refcard.dvi and refcard.ps are available to format it).
6125 * Control-Variable user interface simplified
6127 All variables that control the operation of the debugger can be set
6128 by the ``set'' command, and displayed by the ``show'' command.
6130 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6131 ``Show prompt'' produces the response:
6132 Gdb's prompt is new-gdb=>.
6134 What follows are the NEW set commands. The command ``help set'' will
6135 print a complete list of old and new set commands. ``help set FOO''
6136 will give a longer description of the variable FOO. ``show'' will show
6137 all of the variable descriptions and their current settings.
6139 confirm on/off: Enables warning questions for operations that are
6140 hard to recover from, e.g. rerunning the program while
6141 it is already running. Default is ON.
6143 editing on/off: Enables EMACS style command line editing
6144 of input. Previous lines can be recalled with
6145 control-P, the current line can be edited with control-B,
6146 you can search for commands with control-R, etc.
6149 history filename NAME: NAME is where the gdb command history
6150 will be stored. The default is .gdb_history,
6151 or the value of the environment variable
6154 history size N: The size, in commands, of the command history. The
6155 default is 256, or the value of the environment variable
6158 history save on/off: If this value is set to ON, the history file will
6159 be saved after exiting gdb. If set to OFF, the
6160 file will not be saved. The default is OFF.
6162 history expansion on/off: If this value is set to ON, then csh-like
6163 history expansion will be performed on
6164 command line input. The default is OFF.
6166 radix N: Sets the default radix for input and output. It can be set
6167 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6168 in the current radix, so "set radix 10" is always a no-op.
6170 height N: This integer value is the number of lines on a page. Default
6171 is 24, the current `stty rows'' setting, or the ``li#''
6172 setting from the termcap entry matching the environment
6175 width N: This integer value is the number of characters on a line.
6176 Default is 80, the current `stty cols'' setting, or the ``co#''
6177 setting from the termcap entry matching the environment
6180 Note: ``set screensize'' is obsolete. Use ``set height'' and
6181 ``set width'' instead.
6183 print address on/off: Print memory addresses in various command displays,
6184 such as stack traces and structure values. Gdb looks
6185 more ``symbolic'' if you turn this off; it looks more
6186 ``machine level'' with it on. Default is ON.
6188 print array on/off: Prettyprint arrays. New convenient format! Default
6191 print demangle on/off: Print C++ symbols in "source" form if on,
6194 print asm-demangle on/off: Same, for assembler level printouts
6197 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6200 * Support for Epoch Environment.
6202 The epoch environment is a version of Emacs v18 with windowing. One
6203 new command, ``inspect'', is identical to ``print'', except that if you
6204 are running in the epoch environment, the value is printed in its own
6208 * Support for Shared Libraries
6210 GDB can now debug programs and core files that use SunOS shared libraries.
6211 Symbols from a shared library cannot be referenced
6212 before the shared library has been linked with the program (this
6213 happens after you type ``run'' and before the function main() is entered).
6214 At any time after this linking (including when examining core files
6215 from dynamically linked programs), gdb reads the symbols from each
6216 shared library when you type the ``sharedlibrary'' command.
6217 It can be abbreviated ``share''.
6219 sharedlibrary REGEXP: Load shared object library symbols for files
6220 matching a unix regular expression. No argument
6221 indicates to load symbols for all shared libraries.
6223 info sharedlibrary: Status of loaded shared libraries.
6228 A watchpoint stops execution of a program whenever the value of an
6229 expression changes. Checking for this slows down execution
6230 tremendously whenever you are in the scope of the expression, but is
6231 quite useful for catching tough ``bit-spreader'' or pointer misuse
6232 problems. Some machines such as the 386 have hardware for doing this
6233 more quickly, and future versions of gdb will use this hardware.
6235 watch EXP: Set a watchpoint (breakpoint) for an expression.
6237 info watchpoints: Information about your watchpoints.
6239 delete N: Deletes watchpoint number N (same as breakpoints).
6240 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6241 enable N: Re-enables watchpoint number N (same as breakpoints).
6244 * C++ multiple inheritance
6246 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6249 * C++ exception handling
6251 Gdb now supports limited C++ exception handling. Besides the existing
6252 ability to breakpoint on an exception handler, gdb can breakpoint on
6253 the raising of an exception (before the stack is peeled back to the
6256 catch FOO: If there is a FOO exception handler in the dynamic scope,
6257 set a breakpoint to catch exceptions which may be raised there.
6258 Multiple exceptions (``catch foo bar baz'') may be caught.
6260 info catch: Lists all exceptions which may be caught in the
6261 current stack frame.
6264 * Minor command changes
6266 The command ``call func (arg, arg, ...)'' now acts like the print
6267 command, except it does not print or save a value if the function's result
6268 is void. This is similar to dbx usage.
6270 The ``up'' and ``down'' commands now always print the frame they end up
6271 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6272 frames without printing.
6274 * New directory command
6276 'dir' now adds directories to the FRONT of the source search path.
6277 The path starts off empty. Source files that contain debug information
6278 about the directory in which they were compiled can be found even
6279 with an empty path; Sun CC and GCC include this information. If GDB can't
6280 find your source file in the current directory, type "dir .".
6282 * Configuring GDB for compilation
6284 For normal use, type ``./configure host''. See README or gdb.texinfo
6287 GDB now handles cross debugging. If you are remotely debugging between
6288 two different machines, type ``./configure host -target=targ''.
6289 Host is the machine where GDB will run; targ is the machine
6290 where the program that you are debugging will run.