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.
29 maint set target-non-stop (on|off|auto)
30 maint show target-non-stop
31 Control whether GDB targets always operate in non-stop mode even if
32 "set non-stop" is "off". The default is "auto", meaning non-stop
33 mode is enabled if supported by the target.
36 maint show bfd-sharing
37 Control the reuse of bfd objects.
41 Control display of debugging info regarding bfd caching.
43 set remote multiprocess-extensions-packet
44 show remote multiprocess-extensions-packet
45 Set/show the use of the remote protocol multiprocess extensions.
47 * The "disassemble" command accepts a new modifier: /s.
48 It prints mixed source+disassembly like /m with two differences:
49 - disassembled instructions are now printed in program order, and
50 - and source for all relevant files is now printed.
51 The "/m" option is now considered deprecated: its "source-centric"
52 output hasn't proved useful in practice.
54 * The "set scheduler-locking" command supports a new mode "replay".
55 It behaves like "off" in record mode and like "on" in replay mode.
57 * Support for various ROM monitors has been removed:
59 target dbug dBUG ROM monitor for Motorola ColdFire
60 target picobug Motorola picobug monitor
61 target dink32 DINK32 ROM monitor for PowerPC
62 target m32r Renesas M32R/D ROM monitor
63 target mon2000 mon2000 ROM monitor
64 target ppcbug PPCBUG ROM monitor for PowerPC
66 * Support for reading/writing memory and extracting values on architectures
67 whose memory is addressable in units of any integral multiple of 8 bits.
72 Indicates that an exec system call was executed.
74 exec-events feature in qSupported
75 The qSupported packet allows GDB to request support for exec
76 events using the new 'gdbfeature' exec-event, and the qSupported
77 response can contain the corresponding 'stubfeature'. Set and
78 show commands can be used to display whether these features are enabled.
80 * Extended-remote exec events
82 ** GDB now has support for exec events on extended-remote Linux targets.
83 For such targets with Linux kernels 2.5.46 and later, this enables
84 follow-exec-mode and exec catchpoints.
86 set remote exec-event-feature-packet
87 show remote exec-event-feature-packet
88 Set/show the use of the remote exec event feature.
90 *** Changes in GDB 7.10
92 * Support for process record-replay and reverse debugging on aarch64*-linux*
93 targets has been added. GDB now supports recording of A64 instruction set
94 including advance SIMD instructions.
96 * Support for Sun's version of the "stabs" debug file format has been removed.
98 * GDB now honors the content of the file /proc/PID/coredump_filter
99 (PID is the process ID) on GNU/Linux systems. This file can be used
100 to specify the types of memory mappings that will be included in a
101 corefile. For more information, please refer to the manual page of
102 "core(5)". GDB also has a new command: "set use-coredump-filter
103 on|off". It allows to set whether GDB will read the content of the
104 /proc/PID/coredump_filter file when generating a corefile.
106 * The "info os" command on GNU/Linux can now display information on
108 "info os cpus" Listing of all cpus/cores on the system
110 * GDB has two new commands: "set serial parity odd|even|none" and
111 "show serial parity". These allows to set or show parity for the
114 * The "info source" command now displays the producer string if it was
115 present in the debug info. This typically includes the compiler version
116 and may include things like its command line arguments.
118 * The "info dll", an alias of the "info sharedlibrary" command,
119 is now available on all platforms.
121 * Directory names supplied to the "set sysroot" commands may be
122 prefixed with "target:" to tell GDB to access shared libraries from
123 the target system, be it local or remote. This replaces the prefix
124 "remote:". The default sysroot has been changed from "" to
125 "target:". "remote:" is automatically converted to "target:" for
126 backward compatibility.
128 * The system root specified by "set sysroot" will be prepended to the
129 filename of the main executable (if reported to GDB as absolute by
130 the operating system) when starting processes remotely, and when
131 attaching to already-running local or remote processes.
133 * GDB now supports automatic location and retrieval of executable
134 files from remote targets. Remote debugging can now be initiated
135 using only a "target remote" or "target extended-remote" command
136 (no "set sysroot" or "file" commands are required). See "New remote
139 * The "dump" command now supports verilog hex format.
141 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
143 * On GNU/Linux, GDB and gdbserver are now able to access executable
144 and shared library files without a "set sysroot" command when
145 attaching to processes running in different mount namespaces from
146 the debugger. This makes it possible to attach to processes in
147 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
148 See "New remote packets" below.
150 * The "tui reg" command now provides completion for all of the
151 available register groups, including target specific groups.
153 * The HISTSIZE environment variable is no longer read when determining
154 the size of GDB's command history. GDB now instead reads the dedicated
155 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
156 disables truncation of command history. Non-numeric values of GDBHISTSIZE
161 ** Memory ports can now be unbuffered.
165 ** gdb.Objfile objects have a new attribute "username",
166 which is the name of the objfile as specified by the user,
167 without, for example, resolving symlinks.
168 ** You can now write frame unwinders in Python.
169 ** gdb.Type objects have a new method "optimized_out",
170 returning optimized out gdb.Value instance of this type.
171 ** gdb.Value objects have new methods "reference_value" and
172 "const_value" which return a reference to the value and a
173 "const" version of the value respectively.
177 maint print symbol-cache
178 Print the contents of the symbol cache.
180 maint print symbol-cache-statistics
181 Print statistics of symbol cache usage.
183 maint flush-symbol-cache
184 Flush the contents of the symbol cache.
188 Start branch trace recording using Branch Trace Store (BTS) format.
191 Evaluate expression by using the compiler and print result.
195 Explicit commands for enabling and disabling tui mode.
198 set mpx bound on i386 and amd64
199 Support for bound table investigation on Intel(R) MPX enabled applications.
203 Start branch trace recording using Intel(R) Processor Trace format.
206 Print information about branch tracing internals.
208 maint btrace packet-history
209 Print the raw branch tracing data.
211 maint btrace clear-packet-history
212 Discard the stored raw branch tracing data.
215 Discard all branch tracing data. It will be fetched and processed
216 anew by the next "record" command.
221 Renamed from "set debug dwarf2-die".
223 Renamed from "show debug dwarf2-die".
226 Renamed from "set debug dwarf2-read".
227 show debug dwarf-read
228 Renamed from "show debug dwarf2-read".
230 maint set dwarf always-disassemble
231 Renamed from "maint set dwarf2 always-disassemble".
232 maint show dwarf always-disassemble
233 Renamed from "maint show dwarf2 always-disassemble".
235 maint set dwarf max-cache-age
236 Renamed from "maint set dwarf2 max-cache-age".
237 maint show dwarf max-cache-age
238 Renamed from "maint show dwarf2 max-cache-age".
241 show debug dwarf-line
242 Control display of debugging info regarding DWARF line processing.
246 Set the maximum number of candidates to be considered during
247 completion. The default value is 200. This limit allows GDB
248 to avoid generating large completion lists, the computation of
249 which can cause the debugger to become temporarily unresponsive.
251 set history remove-duplicates
252 show history remove-duplicates
253 Control the removal of duplicate history entries.
255 maint set symbol-cache-size
256 maint show symbol-cache-size
257 Control the size of the symbol cache.
259 set|show record btrace bts buffer-size
260 Set and show the size of the ring buffer used for branch tracing in
262 The obtained size may differ from the requested size. Use "info
263 record" to see the obtained buffer size.
265 set debug linux-namespaces
266 show debug linux-namespaces
267 Control display of debugging info regarding Linux namespaces.
269 set|show record btrace pt buffer-size
270 Set and show the size of the ring buffer used for branch tracing in
271 Intel(R) Processor Trace format.
272 The obtained size may differ from the requested size. Use "info
273 record" to see the obtained buffer size.
275 maint set|show btrace pt skip-pad
276 Set and show whether PAD packets are skipped when computing the
279 * The command 'thread apply all' can now support new option '-ascending'
280 to call its specified command for all threads in ascending order.
282 * Python/Guile scripting
284 ** GDB now supports auto-loading of Python/Guile scripts contained in the
285 special section named `.debug_gdb_scripts'.
289 qXfer:btrace-conf:read
290 Return the branch trace configuration for the current thread.
292 Qbtrace-conf:bts:size
293 Set the requested ring buffer size for branch tracing in BTS format.
296 Enable Intel(R) Procesor Trace-based branch tracing for the current
297 process. The remote stub reports support for this packet to GDB's
301 Set the requested ring buffer size for branch tracing in Intel(R) Processor
305 Indicates a memory breakpoint instruction was executed, irrespective
306 of whether it was GDB that planted the breakpoint or the breakpoint
307 is hardcoded in the program. This is required for correct non-stop
311 Indicates the target stopped for a hardware breakpoint. This is
312 required for correct non-stop mode operation.
315 Return information about files on the remote system.
318 Return the full absolute name of the file that was executed to
319 create a process running on the remote system.
322 Select the filesystem on which vFile: operations with filename
323 arguments will operate. This is required for GDB to be able to
324 access files on remote targets where the remote stub does not
325 share a common filesystem with the inferior(s).
328 Indicates that a fork system call was executed.
331 Indicates that a vfork system call was executed.
333 vforkdone stop reason
334 Indicates that a vfork child of the specified process has executed
335 an exec or exit, allowing the vfork parent to resume execution.
337 fork-events and vfork-events features in qSupported
338 The qSupported packet allows GDB to request support for fork and
339 vfork events using new 'gdbfeatures' fork-events and vfork-events,
340 and the qSupported response can contain the corresponding
341 'stubfeatures'. Set and show commands can be used to display
342 whether these features are enabled.
344 * Extended-remote fork events
346 ** GDB now has support for fork events on extended-remote Linux
347 targets. For targets with Linux kernels 2.5.60 and later, this
348 enables follow-fork-mode and detach-on-fork for both fork and
349 vfork, as well as fork and vfork catchpoints.
351 * The info record command now shows the recording format and the
352 branch tracing configuration for the current thread when using
353 the btrace record target.
354 For the BTS format, it shows the ring buffer size.
356 * GDB now has support for DTrace USDT (Userland Static Defined
357 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
359 * GDB now supports access to vector registers on S/390 GNU/Linux
362 * Removed command line options
364 -xdb HP-UX XDB compatibility mode.
366 * Removed targets and native configurations
368 HP/PA running HP-UX hppa*-*-hpux*
369 Itanium running HP-UX ia64-*-hpux*
371 * New configure options
374 This configure option allows the user to build GDB with support for
375 Intel(R) Processor Trace (default: auto). This requires libipt.
377 --with-libipt-prefix=PATH
378 Specify the path to the version of libipt that GDB should use.
379 $PATH/include should contain the intel-pt.h header and
380 $PATH/lib should contain the libipt.so library.
382 *** Changes in GDB 7.9.1
386 ** Xmethods can now specify a result type.
388 *** Changes in GDB 7.9
390 * GDB now supports hardware watchpoints on x86 GNU Hurd.
394 ** You can now access frame registers from Python scripts.
395 ** New attribute 'producer' for gdb.Symtab objects.
396 ** gdb.Objfile objects have a new attribute "progspace",
397 which is the gdb.Progspace object of the containing program space.
398 ** gdb.Objfile objects have a new attribute "owner".
399 ** gdb.Objfile objects have a new attribute "build_id",
400 which is the build ID generated when the file was built.
401 ** gdb.Objfile objects have a new method "add_separate_debug_file".
402 ** A new event "gdb.clear_objfiles" has been added, triggered when
403 selecting a new file to debug.
404 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
405 ** New function gdb.lookup_objfile.
407 New events which are triggered when GDB modifies the state of the
410 ** gdb.events.inferior_call_pre: Function call is about to be made.
411 ** gdb.events.inferior_call_post: Function call has just been made.
412 ** gdb.events.memory_changed: A memory location has been altered.
413 ** gdb.events.register_changed: A register has been altered.
415 * New Python-based convenience functions:
417 ** $_caller_is(name [, number_of_frames])
418 ** $_caller_matches(regexp [, number_of_frames])
419 ** $_any_caller_is(name [, number_of_frames])
420 ** $_any_caller_matches(regexp [, number_of_frames])
422 * GDB now supports the compilation and injection of source code into
423 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
424 to compile the source code to object code, and if successful, inject
425 and execute that code within the current context of the inferior.
426 Currently the C language is supported. The commands used to
427 interface with this new feature are:
429 compile code [-raw|-r] [--] [source code]
430 compile file [-raw|-r] filename
434 demangle [-l language] [--] name
435 Demangle "name" in the specified language, or the current language
436 if elided. This command is renamed from the "maint demangle" command.
437 The latter is kept as a no-op to avoid "maint demangle" being interpreted
438 as "maint demangler-warning".
440 queue-signal signal-name-or-number
441 Queue a signal to be delivered to the thread when it is resumed.
443 add-auto-load-scripts-directory directory
444 Add entries to the list of directories from which to load auto-loaded
447 maint print user-registers
448 List all currently available "user" registers.
450 compile code [-r|-raw] [--] [source code]
451 Compile, inject, and execute in the inferior the executable object
452 code produced by compiling the provided source code.
454 compile file [-r|-raw] filename
455 Compile and inject into the inferior the executable object code
456 produced by compiling the source code stored in the filename
459 * On resume, GDB now always passes the signal the program had stopped
460 for to the thread the signal was sent to, even if the user changed
461 threads before resuming. Previously GDB would often (but not
462 always) deliver the signal to the thread that happens to be current
465 * Conversely, the "signal" command now consistently delivers the
466 requested signal to the current thread. GDB now asks for
467 confirmation if the program had stopped for a signal and the user
468 switched threads meanwhile.
470 * "breakpoint always-inserted" modes "off" and "auto" merged.
472 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
473 won't remove breakpoints from the target until all threads stop,
474 even in non-stop mode. The "auto" mode has been removed, and "off"
475 is now the default mode.
479 set debug symbol-lookup
480 show debug symbol-lookup
481 Control display of debugging info regarding symbol lookup.
485 ** The -list-thread-groups command outputs an exit-code field for
486 inferiors that have exited.
490 MIPS SDE mips*-sde*-elf*
494 Support for these obsolete configurations has been removed.
496 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
497 SGI Irix-5.x mips-*-irix5*
498 SGI Irix-6.x mips-*-irix6*
499 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
500 VAX running Ultrix vax-*-ultrix*
502 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
503 and "assf"), have been removed. Use the "sharedlibrary" command, or
504 its alias "share", instead.
506 *** Changes in GDB 7.8
508 * New command line options
511 This is an alias for the --data-directory option.
513 * GDB supports printing and modifying of variable length automatic arrays
514 as specified in ISO C99.
516 * The ARM simulator now supports instruction level tracing
517 with or without disassembly.
521 GDB now has support for scripting using Guile. Whether this is
522 available is determined at configure time.
523 Guile version 2.0 or greater is required.
524 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
526 * New commands (for set/show, see "New options" below)
530 Invoke CODE by passing it to the Guile interpreter.
534 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
536 info auto-load guile-scripts [regexp]
537 Print the list of automatically loaded Guile scripts.
539 * The source command is now capable of sourcing Guile scripts.
540 This feature is dependent on the debugger being built with Guile support.
544 set print symbol-loading (off|brief|full)
545 show print symbol-loading
546 Control whether to print informational messages when loading symbol
547 information for a file. The default is "full", but when debugging
548 programs with large numbers of shared libraries the amount of output
551 set guile print-stack (none|message|full)
552 show guile print-stack
553 Show a stack trace when an error is encountered in a Guile script.
555 set auto-load guile-scripts (on|off)
556 show auto-load guile-scripts
557 Control auto-loading of Guile script files.
559 maint ada set ignore-descriptive-types (on|off)
560 maint ada show ignore-descriptive-types
561 Control whether the debugger should ignore descriptive types in Ada
562 programs. The default is not to ignore the descriptive types. See
563 the user manual for more details on descriptive types and the intended
564 usage of this option.
566 set auto-connect-native-target
568 Control whether GDB is allowed to automatically connect to the
569 native target for the run, attach, etc. commands when not connected
570 to any target yet. See also "target native" below.
572 set record btrace replay-memory-access (read-only|read-write)
573 show record btrace replay-memory-access
574 Control what memory accesses are allowed during replay.
576 maint set target-async (on|off)
577 maint show target-async
578 This controls whether GDB targets operate in synchronous or
579 asynchronous mode. Normally the default is asynchronous, if it is
580 available; but this can be changed to more easily debug problems
581 occurring only in synchronous mode.
583 set mi-async (on|off)
585 Control whether MI asynchronous mode is preferred. This supersedes
586 "set target-async" of previous GDB versions.
588 * "set target-async" is deprecated as a CLI option and is now an alias
589 for "set mi-async" (only puts MI into async mode).
591 * Background execution commands (e.g., "c&", "s&", etc.) are now
592 possible ``out of the box'' if the target supports them. Previously
593 the user would need to explicitly enable the possibility with the
594 "set target-async on" command.
596 * New features in the GDB remote stub, GDBserver
598 ** New option --debug-format=option1[,option2,...] allows one to add
599 additional text to each output. At present only timestamps
600 are supported: --debug-format=timestamps.
601 Timestamps can also be turned on with the
602 "monitor set debug-format timestamps" command from GDB.
604 * The 'record instruction-history' command now starts counting instructions
605 at one. This also affects the instruction ranges reported by the
606 'record function-call-history' command when given the /i modifier.
608 * The command 'record function-call-history' supports a new modifier '/c' to
609 indent the function names based on their call stack depth.
610 The fields for the '/i' and '/l' modifier have been reordered.
611 The source line range is now prefixed with 'at'.
612 The instruction range is now prefixed with 'inst'.
613 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
614 "record instruction-history" and "list" commands.
616 * The ranges given as arguments to the 'record function-call-history' and
617 'record instruction-history' commands are now inclusive.
619 * The btrace record target now supports the 'record goto' command.
620 For locations inside the execution trace, the back trace is computed
621 based on the information stored in the execution trace.
623 * The btrace record target supports limited reverse execution and replay.
624 The target does not record data and therefore does not allow reading
627 * The "catch syscall" command now works on s390*-linux* targets.
629 * The "compare-sections" command is no longer specific to target
630 remote. It now works with all targets.
632 * All native targets are now consistently called "native".
633 Consequently, the "target child", "target GNU", "target djgpp",
634 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
635 commands have been replaced with "target native". The QNX/NTO port
636 leaves the "procfs" target in place and adds a "native" target for
637 consistency with other ports. The impact on users should be minimal
638 as these commands previously either throwed an error, or were
639 no-ops. The target's name is visible in the output of the following
640 commands: "help target", "info target", "info files", "maint print
643 * The "target native" command now connects to the native target. This
644 can be used to launch native programs even when "set
645 auto-connect-native-target" is set to off.
647 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
649 * Support for Intel(R) AVX-512 registers on GNU/Linux.
650 Support displaying and modifying Intel(R) AVX-512 registers
651 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
655 qXfer:btrace:read's annex
656 The qXfer:btrace:read packet supports a new annex 'delta' to read
657 branch trace incrementally.
661 ** Valid Python operations on gdb.Value objects representing
662 structs/classes invoke the corresponding overloaded operators if
664 ** New `Xmethods' feature in the Python API. Xmethods are
665 additional methods or replacements for existing methods of a C++
666 class. This feature is useful for those cases where a method
667 defined in C++ source code could be inlined or optimized out by
668 the compiler, making it unavailable to GDB.
671 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
673 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
674 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
675 its alias "share", instead.
677 * The commands "set remotebaud" and "show remotebaud" are no longer
678 supported. Use "set serial baud" and "show serial baud" (respectively)
683 ** A new option "-gdb-set mi-async" replaces "-gdb-set
684 target-async". The latter is left as a deprecated alias of the
685 former for backward compatibility. If the target supports it,
686 CLI background execution commands are now always possible by
687 default, independently of whether the frontend stated a
688 preference for asynchronous execution with "-gdb-set mi-async".
689 Previously "-gdb-set target-async off" affected both MI execution
690 commands and CLI execution commands.
692 *** Changes in GDB 7.7
694 * Improved support for process record-replay and reverse debugging on
695 arm*-linux* targets. Support for thumb32 and syscall instruction
696 recording has been added.
698 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
700 * GDB now supports Fission DWP file format version 2.
701 http://gcc.gnu.org/wiki/DebugFission
703 * New convenience function "$_isvoid", to check whether an expression
704 is void. A void expression is an expression where the type of the
705 result is "void". For example, some convenience variables may be
706 "void" when evaluated (e.g., "$_exitcode" before the execution of
707 the program being debugged; or an undefined convenience variable).
708 Another example, when calling a function whose return type is
711 * The "maintenance print objfiles" command now takes an optional regexp.
713 * The "catch syscall" command now works on arm*-linux* targets.
715 * GDB now consistently shows "<not saved>" when printing values of
716 registers the debug info indicates have not been saved in the frame
717 and there's nowhere to retrieve them from
718 (callee-saved/call-clobbered registers):
723 (gdb) info registers rax
726 Before, the former would print "<optimized out>", and the latter
727 "*value not available*".
729 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
734 ** Frame filters and frame decorators have been added.
735 ** Temporary breakpoints are now supported.
736 ** Line tables representation has been added.
737 ** New attribute 'parent_type' for gdb.Field objects.
738 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
739 ** New attribute 'name' for gdb.Type objects.
743 Nios II ELF nios2*-*-elf
744 Nios II GNU/Linux nios2*-*-linux
745 Texas Instruments MSP430 msp430*-*-elf
747 * Removed native configurations
749 Support for these a.out NetBSD and OpenBSD obsolete configurations has
750 been removed. ELF variants of these configurations are kept supported.
752 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
753 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
754 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
755 i[34567]86-*-openbsd3.[0-3]
756 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
757 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
758 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
762 Like "catch throw", but catches a re-thrown exception.
764 Renamed from old "maint check-symtabs".
766 Perform consistency checks on symtabs.
768 Expand symtabs matching an optional regexp.
771 Display the details of GDB configure-time options.
773 maint set|show per-command
774 maint set|show per-command space
775 maint set|show per-command time
776 maint set|show per-command symtab
777 Enable display of per-command gdb resource usage.
779 remove-symbol-file FILENAME
780 remove-symbol-file -a ADDRESS
781 Remove a symbol file added via add-symbol-file. The file to remove
782 can be identified by its filename or by an address that lies within
783 the boundaries of this symbol file in memory.
786 info exceptions REGEXP
787 Display the list of Ada exceptions defined in the program being
788 debugged. If provided, only the exceptions whose names match REGEXP
793 set debug symfile off|on
795 Control display of debugging info regarding reading symbol files and
796 symbol tables within those files
798 set print raw frame-arguments
799 show print raw frame-arguments
800 Set/show whether to print frame arguments in raw mode,
801 disregarding any defined pretty-printers.
803 set remote trace-status-packet
804 show remote trace-status-packet
805 Set/show the use of remote protocol qTStatus packet.
809 Control display of debugging messages related to Nios II targets.
813 Control whether target-assisted range stepping is enabled.
815 set startup-with-shell
816 show startup-with-shell
817 Specifies whether Unix child processes are started via a shell or
822 Use the target memory cache for accesses to the code segment. This
823 improves performance of remote debugging (particularly disassembly).
825 * You can now use a literal value 'unlimited' for options that
826 interpret 0 or -1 as meaning "unlimited". E.g., "set
827 trace-buffer-size unlimited" is now an alias for "set
828 trace-buffer-size -1" and "set height unlimited" is now an alias for
831 * The "set debug symtab-create" debugging option of GDB has been changed to
832 accept a verbosity level. 0 means "off", 1 provides basic debugging
833 output, and values of 2 or greater provides more verbose output.
835 * New command-line options
837 Display the details of GDB configure-time options.
839 * The command 'tsave' can now support new option '-ctf' to save trace
840 buffer in Common Trace Format.
842 * Newly installed $prefix/bin/gcore acts as a shell interface for the
845 * GDB now implements the the C++ 'typeid' operator.
847 * The new convenience variable $_exception holds the exception being
848 thrown or caught at an exception-related catchpoint.
850 * The exception-related catchpoints, like "catch throw", now accept a
851 regular expression which can be used to filter exceptions by type.
853 * The new convenience variable $_exitsignal is automatically set to
854 the terminating signal number when the program being debugged dies
855 due to an uncaught signal.
859 ** All MI commands now accept an optional "--language" option.
860 Support for this feature can be verified by using the "-list-features"
861 command, which should contain "language-option".
863 ** The new command -info-gdb-mi-command allows the user to determine
864 whether a GDB/MI command is supported or not.
866 ** The "^error" result record returned when trying to execute an undefined
867 GDB/MI command now provides a variable named "code" whose content is the
868 "undefined-command" error code. Support for this feature can be verified
869 by using the "-list-features" command, which should contain
870 "undefined-command-error-code".
872 ** The -trace-save MI command can optionally save trace buffer in Common
875 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
877 ** The command -data-list-register-values now accepts an optional
878 "--skip-unavailable" option. When used, only the available registers
881 ** The new command -trace-frame-collected dumps collected variables,
882 computed expressions, tvars, memory and registers in a traceframe.
884 ** The commands -stack-list-locals, -stack-list-arguments and
885 -stack-list-variables now accept an option "--skip-unavailable".
886 When used, only the available locals or arguments are displayed.
888 ** The -exec-run command now accepts an optional "--start" option.
889 When used, the command follows the same semantics as the "start"
890 command, stopping the program's execution at the start of its
891 main subprogram. Support for this feature can be verified using
892 the "-list-features" command, which should contain
893 "exec-run-start-option".
895 ** The new commands -catch-assert and -catch-exceptions insert
896 catchpoints stopping the program when Ada exceptions are raised.
898 ** The new command -info-ada-exceptions provides the equivalent of
899 the new "info exceptions" command.
901 * New system-wide configuration scripts
902 A GDB installation now provides scripts suitable for use as system-wide
903 configuration scripts for the following systems:
907 * GDB now supports target-assigned range stepping with remote targets.
908 This improves the performance of stepping source lines by reducing
909 the number of control packets from/to GDB. See "New remote packets"
912 * GDB now understands the element 'tvar' in the XML traceframe info.
913 It has the id of the collected trace state variables.
915 * On S/390 targets that provide the transactional-execution feature,
916 the program interruption transaction diagnostic block (TDB) is now
917 represented as a number of additional "registers" in GDB.
923 The vCont packet supports a new 'r' action, that tells the remote
924 stub to step through an address range itself, without GDB
925 involvemement at each single-step.
927 qXfer:libraries-svr4:read's annex
928 The previously unused annex of the qXfer:libraries-svr4:read packet
929 is now used to support passing an argument list. The remote stub
930 reports support for this argument list to GDB's qSupported query.
931 The defined arguments are "start" and "prev", used to reduce work
932 necessary for library list updating, resulting in significant
935 * New features in the GDB remote stub, GDBserver
937 ** GDBserver now supports target-assisted range stepping. Currently
938 enabled on x86/x86_64 GNU/Linux targets.
940 ** GDBserver now adds element 'tvar' in the XML in the reply to
941 'qXfer:traceframe-info:read'. It has the id of the collected
942 trace state variables.
944 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
947 * New 'z' formatter for printing and examining memory, this displays the
948 value as hexadecimal zero padded on the left to the size of the type.
950 * GDB can now use Windows x64 unwinding data.
952 * The "set remotebaud" command has been replaced by "set serial baud".
953 Similarly, "show remotebaud" has been replaced by "show serial baud".
954 The "set remotebaud" and "show remotebaud" commands are still available
955 to provide backward compatibility with older versions of GDB.
957 *** Changes in GDB 7.6
959 * Target record has been renamed to record-full.
960 Record/replay is now enabled with the "record full" command.
961 This also affects settings that are associated with full record/replay
962 that have been moved from "set/show record" to "set/show record full":
964 set|show record full insn-number-max
965 set|show record full stop-at-limit
966 set|show record full memory-query
968 * A new record target "record-btrace" has been added. The new target
969 uses hardware support to record the control-flow of a process. It
970 does not support replaying the execution, but it implements the
971 below new commands for investigating the recorded execution log.
972 This new recording method can be enabled using:
976 The "record-btrace" target is only available on Intel Atom processors
977 and requires a Linux kernel 2.6.32 or later.
979 * Two new commands have been added for record/replay to give information
980 about the recorded execution without having to replay the execution.
981 The commands are only supported by "record btrace".
983 record instruction-history prints the execution history at
984 instruction granularity
986 record function-call-history prints the execution history at
989 * New native configurations
991 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
992 FreeBSD/powerpc powerpc*-*-freebsd
993 x86_64/Cygwin x86_64-*-cygwin*
994 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
998 ARM AArch64 aarch64*-*-elf
999 ARM AArch64 GNU/Linux aarch64*-*-linux
1000 Lynx 178 PowerPC powerpc-*-lynx*178
1001 x86_64/Cygwin x86_64-*-cygwin*
1002 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1004 * If the configured location of system.gdbinit file (as given by the
1005 --with-system-gdbinit option at configure time) is in the
1006 data-directory (as specified by --with-gdb-datadir at configure
1007 time) or in one of its subdirectories, then GDB will look for the
1008 system-wide init file in the directory specified by the
1009 --data-directory command-line option.
1011 * New command line options:
1013 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1014 other initialization files, unlike -nx which disables all of them.
1016 * Removed command line options
1018 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1021 * The 'ptype' and 'whatis' commands now accept an argument to control
1024 * 'info proc' now works on some core files.
1028 ** Vectors can be created with gdb.Type.vector.
1030 ** Python's atexit.register now works in GDB.
1032 ** Types can be pretty-printed via a Python API.
1034 ** Python 3 is now supported (in addition to Python 2.4 or later)
1036 ** New class gdb.Architecture exposes GDB's internal representation
1037 of architecture in the Python API.
1039 ** New method Frame.architecture returns the gdb.Architecture object
1040 corresponding to the frame's architecture.
1042 * New Python-based convenience functions:
1044 ** $_memeq(buf1, buf2, length)
1045 ** $_streq(str1, str2)
1047 ** $_regex(str, regex)
1049 * The 'cd' command now defaults to using '~' (the home directory) if not
1052 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1053 default for GCC since November 2000.
1055 * The command 'forward-search' can now be abbreviated as 'fo'.
1057 * The command 'info tracepoints' can now display 'installed on target'
1058 or 'not installed on target' for each non-pending location of tracepoint.
1060 * New configure options
1062 --enable-libmcheck/--disable-libmcheck
1063 By default, development versions are built with -lmcheck on hosts
1064 that support it, in order to help track memory corruption issues.
1065 Release versions, on the other hand, are built without -lmcheck
1066 by default. The --enable-libmcheck/--disable-libmcheck configure
1067 options allow the user to override that default.
1068 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1069 This configure option allows the user to build GDB with
1070 libbabeltrace using which GDB can read Common Trace Format data.
1072 * New commands (for set/show, see "New options" below)
1075 Catch signals. This is similar to "handle", but allows commands and
1076 conditions to be attached.
1079 List the BFDs known to GDB.
1081 python-interactive [command]
1083 Start a Python interactive prompt, or evaluate the optional command
1084 and print the result of expressions.
1087 "py" is a new alias for "python".
1089 enable type-printer [name]...
1090 disable type-printer [name]...
1091 Enable or disable type printers.
1095 ** For the Renesas Super-H architecture, the "regs" command has been removed
1096 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1101 set print type methods (on|off)
1102 show print type methods
1103 Control whether method declarations are displayed by "ptype".
1104 The default is to show them.
1106 set print type typedefs (on|off)
1107 show print type typedefs
1108 Control whether typedef definitions are displayed by "ptype".
1109 The default is to show them.
1111 set filename-display basename|relative|absolute
1112 show filename-display
1113 Control the way in which filenames is displayed.
1114 The default is "relative", which preserves previous behavior.
1116 set trace-buffer-size
1117 show trace-buffer-size
1118 Request target to change the size of trace buffer.
1120 set remote trace-buffer-size-packet auto|on|off
1121 show remote trace-buffer-size-packet
1122 Control the use of the remote protocol `QTBuffer:size' packet.
1126 Control display of debugging messages related to ARM AArch64.
1129 set debug coff-pe-read
1130 show debug coff-pe-read
1131 Control display of debugging messages related to reading of COFF/PE
1136 Control display of debugging messages related to Mach-O symbols
1139 set debug notification
1140 show debug notification
1141 Control display of debugging info for async remote notification.
1145 ** Command parameter changes are now notified using new async record
1146 "=cmd-param-changed".
1147 ** Trace frame changes caused by command "tfind" are now notified using
1148 new async record "=traceframe-changed".
1149 ** The creation, deletion and modification of trace state variables
1150 are now notified using new async records "=tsv-created",
1151 "=tsv-deleted" and "=tsv-modified".
1152 ** The start and stop of process record are now notified using new
1153 async record "=record-started" and "=record-stopped".
1154 ** Memory changes are now notified using new async record
1156 ** The data-disassemble command response will include a "fullname" field
1157 containing the absolute file name when source has been requested.
1158 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1159 command, to allow pattern filling of memory areas.
1160 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1161 library load/unload events.
1162 ** The response to breakpoint commands and breakpoint async records
1163 includes an "installed" field containing a boolean state about each
1164 non-pending tracepoint location is whether installed on target or not.
1165 ** Output of the "-trace-status" command includes a "trace-file" field
1166 containing the name of the trace file being examined. This field is
1167 optional, and only present when examining a trace file.
1168 ** The "fullname" field is now always present along with the "file" field,
1169 even if the file cannot be found by GDB.
1171 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1172 You must have the LZMA library available when configuring GDB for this
1173 feature to be enabled. For more information, see:
1174 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1176 * New remote packets
1179 Set the size of trace buffer. The remote stub reports support for this
1180 packet to gdb's qSupported query.
1183 Enable Branch Trace Store (BTS)-based branch tracing for the current
1184 thread. The remote stub reports support for this packet to gdb's
1188 Disable branch tracing for the current thread. The remote stub reports
1189 support for this packet to gdb's qSupported query.
1192 Read the traced branches for the current thread. The remote stub
1193 reports support for this packet to gdb's qSupported query.
1195 *** Changes in GDB 7.5
1197 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1198 for more x32 ABI info.
1200 * GDB now supports access to MIPS DSP registers on Linux targets.
1202 * GDB now supports debugging microMIPS binaries.
1204 * The "info os" command on GNU/Linux can now display information on
1205 several new classes of objects managed by the operating system:
1206 "info os procgroups" lists process groups
1207 "info os files" lists file descriptors
1208 "info os sockets" lists internet-domain sockets
1209 "info os shm" lists shared-memory regions
1210 "info os semaphores" lists semaphores
1211 "info os msg" lists message queues
1212 "info os modules" lists loaded kernel modules
1214 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1215 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1216 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1217 options and inspect the probe arguments using the new $_probe_arg family
1218 of convenience variables. You can obtain more information about SystemTap
1219 in <http://sourceware.org/systemtap/>.
1221 * GDB now supports reversible debugging on ARM, it allows you to
1222 debug basic ARM and THUMB instructions, and provides
1223 record/replay support.
1225 * The option "symbol-reloading" has been deleted as it is no longer used.
1229 ** GDB commands implemented in Python can now be put in command class
1232 ** The "maint set python print-stack on|off" is now deleted.
1234 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1235 apply "flag enum"-style pretty-printing to any enum.
1237 ** gdb.lookup_symbol can now work when there is no current frame.
1239 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1240 the source at which the symbol was defined.
1242 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1243 method 'value'. The former indicates whether the symbol needs a
1244 frame in order to compute its value, and the latter computes the
1247 ** A new method 'referenced_value' on gdb.Value objects which can
1248 dereference pointer as well as C++ reference values.
1250 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1251 which return the global and static blocks (as gdb.Block objects),
1252 of the underlying symbol table, respectively.
1254 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1255 object associated with a PC value.
1257 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1258 of the address range occupied by code for the current source line.
1260 * Go language support.
1261 GDB now supports debugging programs written in the Go programming
1264 * GDBserver now supports stdio connections.
1265 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1267 * The binary "gdbtui" can no longer be built or installed.
1268 Use "gdb -tui" instead.
1270 * GDB will now print "flag" enums specially. A flag enum is one where
1271 all the enumerator values have no bits in common when pairwise
1272 "and"ed. When printing a value whose type is a flag enum, GDB will
1273 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1274 (gdb) print (enum E) 3
1277 * The filename part of a linespec will now match trailing components
1278 of a source file name. For example, "break gcc/expr.c:1000" will
1279 now set a breakpoint in build/gcc/expr.c, but not
1280 build/libcpp/expr.c.
1282 * The "info proc" and "generate-core-file" commands will now also
1283 work on remote targets connected to GDBserver on Linux.
1285 * The command "info catch" has been removed. It has been disabled
1286 since December 2007.
1288 * The "catch exception" and "catch assert" commands now accept
1289 a condition at the end of the command, much like the "break"
1290 command does. For instance:
1292 (gdb) catch exception Constraint_Error if Barrier = True
1294 Previously, it was possible to add a condition to such catchpoints,
1295 but it had to be done as a second step, after the catchpoint had been
1296 created, using the "condition" command.
1298 * The "info static-tracepoint-marker" command will now also work on
1299 native Linux targets with in-process agent.
1301 * GDB can now set breakpoints on inlined functions.
1303 * The .gdb_index section has been updated to include symbols for
1304 inlined functions. GDB will ignore older .gdb_index sections by
1305 default, which could cause symbol files to be loaded more slowly
1306 until their .gdb_index sections can be recreated. The new command
1307 "set use-deprecated-index-sections on" will cause GDB to use any older
1308 .gdb_index sections it finds. This will restore performance, but the
1309 ability to set breakpoints on inlined functions will be lost in symbol
1310 files with older .gdb_index sections.
1312 The .gdb_index section has also been updated to record more information
1313 about each symbol. This speeds up the "info variables", "info functions"
1314 and "info types" commands when used with programs having the .gdb_index
1315 section, as well as speeding up debugging with shared libraries using
1316 the .gdb_index section.
1318 * Ada support for GDB/MI Variable Objects has been added.
1320 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1325 ** New command -info-os is the MI equivalent of "info os".
1327 ** Output logs ("set logging" and related) now include MI output.
1331 ** "set use-deprecated-index-sections on|off"
1332 "show use-deprecated-index-sections on|off"
1333 Controls the use of deprecated .gdb_index sections.
1335 ** "catch load" and "catch unload" can be used to stop when a shared
1336 library is loaded or unloaded, respectively.
1338 ** "enable count" can be used to auto-disable a breakpoint after
1341 ** "info vtbl" can be used to show the virtual method tables for
1342 C++ and Java objects.
1344 ** "explore" and its sub commands "explore value" and "explore type"
1345 can be used to recursively explore values and types of
1346 expressions. These commands are available only if GDB is
1347 configured with '--with-python'.
1349 ** "info auto-load" shows status of all kinds of auto-loaded files,
1350 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1351 sequences of commands files, "info auto-load python-scripts"
1352 shows status of auto-loading Python script files,
1353 "info auto-load local-gdbinit" shows status of loading init file
1354 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1355 status of inferior specific thread debugging shared library loading.
1357 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1358 and "show auto-load-scripts" commands have been deprecated, use their
1359 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1360 and "show auto-load python-scripts" counterparts instead.
1362 ** "dprintf location,format,args..." creates a dynamic printf, which
1363 is basically a breakpoint that does a printf and immediately
1364 resumes your program's execution, so it is like a printf that you
1365 can insert dynamically at runtime instead of at compiletime.
1367 ** "set print symbol"
1369 Controls whether GDB attempts to display the symbol, if any,
1370 corresponding to addresses it prints. This defaults to "on", but
1371 you can set it to "off" to restore GDB's previous behavior.
1373 * Deprecated commands
1375 ** For the Renesas Super-H architecture, the "regs" command has been
1376 deprecated, and "info all-registers" should be used instead.
1380 Renesas RL78 rl78-*-elf
1381 HP OpenVMS ia64 ia64-hp-openvms*
1383 * GDBserver supports evaluation of breakpoint conditions. When
1384 support is advertised by GDBserver, GDB may be told to send the
1385 breakpoint conditions in bytecode form to GDBserver. GDBserver
1386 will only report the breakpoint trigger to GDB when its condition
1391 set mips compression
1392 show mips compression
1393 Select the compressed ISA encoding used in functions that have no symbol
1394 information available. The encoding can be set to either of:
1397 and is updated automatically from ELF file flags if available.
1399 set breakpoint condition-evaluation
1400 show breakpoint condition-evaluation
1401 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1402 GDBserver ("target"). Default option "auto" chooses the most efficient
1404 This option can improve debugger efficiency depending on the speed of the
1408 Disable auto-loading globally.
1411 Show auto-loading setting of all kinds of auto-loaded files.
1413 set auto-load gdb-scripts on|off
1414 show auto-load gdb-scripts
1415 Control auto-loading of GDB canned sequences of commands files.
1417 set auto-load python-scripts on|off
1418 show auto-load python-scripts
1419 Control auto-loading of Python script files.
1421 set auto-load local-gdbinit on|off
1422 show auto-load local-gdbinit
1423 Control loading of init file (.gdbinit) from current directory.
1425 set auto-load libthread-db on|off
1426 show auto-load libthread-db
1427 Control auto-loading of inferior specific thread debugging shared library.
1429 set auto-load scripts-directory <dir1>[:<dir2>...]
1430 show auto-load scripts-directory
1431 Set a list of directories from which to load auto-loaded scripts.
1432 Automatically loaded Python scripts and GDB scripts are located in one
1433 of the directories listed by this option.
1434 The delimiter (':' above) may differ according to the host platform.
1436 set auto-load safe-path <dir1>[:<dir2>...]
1437 show auto-load safe-path
1438 Set a list of directories from which it is safe to auto-load files.
1439 The delimiter (':' above) may differ according to the host platform.
1441 set debug auto-load on|off
1442 show debug auto-load
1443 Control display of debugging info for auto-loading the files above.
1445 set dprintf-style gdb|call|agent
1447 Control the way in which a dynamic printf is performed; "gdb"
1448 requests a GDB printf command, while "call" causes dprintf to call a
1449 function in the inferior. "agent" requests that the target agent
1450 (such as GDBserver) do the printing.
1452 set dprintf-function <expr>
1453 show dprintf-function
1454 set dprintf-channel <expr>
1455 show dprintf-channel
1456 Set the function and optional first argument to the call when using
1457 the "call" style of dynamic printf.
1459 set disconnected-dprintf on|off
1460 show disconnected-dprintf
1461 Control whether agent-style dynamic printfs continue to be in effect
1462 after GDB disconnects.
1464 * New configure options
1466 --with-auto-load-dir
1467 Configure default value for the 'set auto-load scripts-directory'
1468 setting above. It defaults to '$debugdir:$datadir/auto-load',
1469 $debugdir representing global debugging info directories (available
1470 via 'show debug-file-directory') and $datadir representing GDB's data
1471 directory (available via 'show data-directory').
1473 --with-auto-load-safe-path
1474 Configure default value for the 'set auto-load safe-path' setting
1475 above. It defaults to the --with-auto-load-dir setting.
1477 --without-auto-load-safe-path
1478 Set 'set auto-load safe-path' to '/', effectively disabling this
1481 * New remote packets
1483 z0/z1 conditional breakpoints extension
1485 The z0/z1 breakpoint insertion packets have been extended to carry
1486 a list of conditional expressions over to the remote stub depending on the
1487 condition evaluation mode. The use of this extension can be controlled
1488 via the "set remote conditional-breakpoints-packet" command.
1492 Specify the signals which the remote stub may pass to the debugged
1493 program without GDB involvement.
1495 * New command line options
1497 --init-command=FILE, -ix Like --command, -x but execute it
1498 before loading inferior.
1499 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1500 execute it before loading inferior.
1502 *** Changes in GDB 7.4
1504 * GDB now handles ambiguous linespecs more consistently; the existing
1505 FILE:LINE support has been expanded to other types of linespecs. A
1506 breakpoint will now be set on all matching locations in all
1507 inferiors, and locations will be added or removed according to
1510 * GDB now allows you to skip uninteresting functions and files when
1511 stepping with the "skip function" and "skip file" commands.
1513 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1514 and "show remote hardware-watchpoint-length-limit". These allows to
1515 set or show the maximum length limit (in bytes) of a remote
1516 target hardware watchpoint.
1518 This allows e.g. to use "unlimited" hardware watchpoints with the
1519 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1520 watchpoints are slower than real hardware watchpoints but are
1521 significantly faster than gdb software watchpoints.
1525 ** The register_pretty_printer function in module gdb.printing now takes
1526 an optional `replace' argument. If True, the new printer replaces any
1529 ** The "maint set python print-stack on|off" command has been
1530 deprecated and will be deleted in GDB 7.5.
1531 A new command: "set python print-stack none|full|message" has
1532 replaced it. Additionally, the default for "print-stack" is
1533 now "message", which just prints the error message without
1536 ** A prompt substitution hook (prompt_hook) is now available to the
1539 ** A new Python module, gdb.prompt has been added to the GDB Python
1540 modules library. This module provides functionality for
1541 escape sequences in prompts (used by set/show
1542 extended-prompt). These escape sequences are replaced by their
1543 corresponding value.
1545 ** Python commands and convenience-functions located in
1546 'data-directory'/python/gdb/command and
1547 'data-directory'/python/gdb/function are now automatically loaded
1550 ** Blocks now provide four new attributes. global_block and
1551 static_block will return the global and static blocks
1552 respectively. is_static and is_global are boolean attributes
1553 that indicate if the block is one of those two types.
1555 ** Symbols now provide the "type" attribute, the type of the symbol.
1557 ** The "gdb.breakpoint" function has been deprecated in favor of
1560 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1561 of a function. This class is based on the "finish" command
1562 available in the CLI.
1564 ** Type objects for struct and union types now allow access to
1565 the fields using standard Python dictionary (mapping) methods.
1566 For example, "some_type['myfield']" now works, as does
1567 "some_type.items()".
1569 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1572 ** A new function, "deep_items" has been added to the gdb.types
1573 module in the GDB Python modules library. This function returns
1574 an iterator over the fields of a struct or union type. Unlike
1575 the standard Python "iteritems" method, it will recursively traverse
1576 any anonymous fields.
1580 ** "*stopped" events can report several new "reason"s, such as
1583 ** Breakpoint changes are now notified using new async records, like
1584 "=breakpoint-modified".
1586 ** New command -ada-task-info.
1588 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1589 $sdir specifies the default system locations of shared libraries.
1590 $pdir specifies the directory where the libpthread used by the application
1593 GDB no longer looks in $sdir and $pdir after it has searched the directories
1594 mentioned in libthread-db-search-path. If you want to search those
1595 directories, they must be specified in libthread-db-search-path.
1596 The default value of libthread-db-search-path on GNU/Linux and Solaris
1597 systems is now "$sdir:$pdir".
1599 $pdir is not supported by gdbserver, it is currently ignored.
1600 $sdir is supported by gdbserver.
1602 * New configure option --with-iconv-bin.
1603 When using the internationalization support like the one in the GNU C
1604 library, GDB will invoke the "iconv" program to get a list of supported
1605 character sets. If this program lives in a non-standard location, one can
1606 use this option to specify where to find it.
1608 * When natively debugging programs on PowerPC BookE processors running
1609 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1610 watchpoints, which specify a mask in addition to an address to watch.
1611 The mask specifies that some bits of an address (the bits which are
1612 reset in the mask) should be ignored when matching the address accessed
1613 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1614 section in the user manual for more details.
1616 * The new option --once causes GDBserver to stop listening for connections once
1617 the first connection is made. The listening port used by GDBserver will
1618 become available after that.
1620 * New commands "info macros" and "alias" have been added.
1622 * New function parameters suffix @entry specifies value of function parameter
1623 at the time the function got called. Entry values are available only since
1629 "!" is now an alias of the "shell" command.
1630 Note that no space is needed between "!" and SHELL COMMAND.
1634 watch EXPRESSION mask MASK_VALUE
1635 The watch command now supports the mask argument which allows creation
1636 of masked watchpoints, if the current architecture supports this feature.
1638 info auto-load-scripts [REGEXP]
1639 This command was formerly named "maintenance print section-scripts".
1640 It is now generally useful and is no longer a maintenance-only command.
1642 info macro [-all] [--] MACRO
1643 The info macro command has new options `-all' and `--'. The first for
1644 printing all definitions of a macro. The second for explicitly specifying
1645 the end of arguments and the beginning of the macro name in case the macro
1646 name starts with a hyphen.
1648 collect[/s] EXPRESSIONS
1649 The tracepoint collect command now takes an optional modifier "/s"
1650 that directs it to dereference pointer-to-character types and
1651 collect the bytes of memory up to a zero byte. The behavior is
1652 similar to what you see when you use the regular print command on a
1653 string. An optional integer following the "/s" sets a bound on the
1654 number of bytes that will be collected.
1657 The trace start command now interprets any supplied arguments as a
1658 note to be recorded with the trace run, with an effect similar to
1659 setting the variable trace-notes.
1662 The trace stop command now interprets any arguments as a note to be
1663 mentioned along with the tstatus report that the trace was stopped
1664 with a command. The effect is similar to setting the variable
1667 * Tracepoints can now be enabled and disabled at any time after a trace
1668 experiment has been started using the standard "enable" and "disable"
1669 commands. It is now possible to start a trace experiment with no enabled
1670 tracepoints; GDB will display a warning, but will allow the experiment to
1671 begin, assuming that tracepoints will be enabled as needed while the trace
1674 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1675 locations with 4-byte instructions, when they were previously
1676 limited to locations with instructions of 5 bytes or longer.
1680 set debug dwarf2-read
1681 show debug dwarf2-read
1682 Turns on or off display of debugging messages related to reading
1683 DWARF debug info. The default is off.
1685 set debug symtab-create
1686 show debug symtab-create
1687 Turns on or off display of debugging messages related to symbol table
1688 creation. The default is off.
1691 show extended-prompt
1692 Set the GDB prompt, and allow escape sequences to be inserted to
1693 display miscellaneous information (see 'help set extended-prompt'
1694 for the list of sequences). This prompt (and any information
1695 accessed through the escape sequences) is updated every time the
1696 prompt is displayed.
1698 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1699 show print entry-values
1700 Set printing of frame argument values at function entry. In some cases
1701 GDB can determine the value of function argument which was passed by the
1702 function caller, even if the value was modified inside the called function.
1704 set debug entry-values
1705 show debug entry-values
1706 Control display of debugging info for determining frame argument values at
1707 function entry and virtual tail call frames.
1709 set basenames-may-differ
1710 show basenames-may-differ
1711 Set whether a source file may have multiple base names.
1712 (A "base name" is the name of a file with the directory part removed.
1713 Example: The base name of "/home/user/hello.c" is "hello.c".)
1714 If set, GDB will canonicalize file names (e.g., expand symlinks)
1715 before comparing them. Canonicalization is an expensive operation,
1716 but it allows the same file be known by more than one base name.
1717 If not set (the default), all source files are assumed to have just
1718 one base name, and gdb will do file name comparisons more efficiently.
1724 Set a user name and notes for the current and any future trace runs.
1725 This is useful for long-running and/or disconnected traces, to
1726 inform others (or yourself) as to who is running the trace, supply
1727 contact information, or otherwise explain what is going on.
1729 set trace-stop-notes
1730 show trace-stop-notes
1731 Set a note attached to the trace run, that is displayed when the
1732 trace has been stopped by a tstop command. This is useful for
1733 instance as an explanation, if you are stopping a trace run that was
1734 started by someone else.
1736 * New remote packets
1740 Dynamically enable a tracepoint in a started trace experiment.
1744 Dynamically disable a tracepoint in a started trace experiment.
1748 Set the user and notes of the trace run.
1752 Query the current status of a tracepoint.
1756 Query the minimum length of instruction at which a fast tracepoint may
1759 * Dcache size (number of lines) and line-size are now runtime-configurable
1760 via "set dcache line" and "set dcache line-size" commands.
1764 Texas Instruments TMS320C6x tic6x-*-*
1768 Renesas RL78 rl78-*-elf
1770 *** Changes in GDB 7.3.1
1772 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1774 *** Changes in GDB 7.3
1776 * GDB has a new command: "thread find [REGEXP]".
1777 It finds the thread id whose name, target id, or thread extra info
1778 matches the given regular expression.
1780 * The "catch syscall" command now works on mips*-linux* targets.
1782 * The -data-disassemble MI command now supports modes 2 and 3 for
1783 dumping the instruction opcodes.
1785 * New command line options
1787 -data-directory DIR Specify DIR as the "data-directory".
1788 This is mostly for testing purposes.
1790 * The "maint set python auto-load on|off" command has been renamed to
1791 "set auto-load-scripts on|off".
1793 * GDB has a new command: "set directories".
1794 It is like the "dir" command except that it replaces the
1795 source path list instead of augmenting it.
1797 * GDB now understands thread names.
1799 On GNU/Linux, "info threads" will display the thread name as set by
1800 prctl or pthread_setname_np.
1802 There is also a new command, "thread name", which can be used to
1803 assign a name internally for GDB to display.
1806 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1807 has been integrated into GDB.
1811 ** The function gdb.Write now accepts an optional keyword 'stream'.
1812 This keyword, when provided, will direct the output to either
1813 stdout, stderr, or GDB's logging output.
1815 ** Parameters can now be be sub-classed in Python, and in particular
1816 you may implement the get_set_doc and get_show_doc functions.
1817 This improves how Parameter set/show documentation is processed
1818 and allows for more dynamic content.
1820 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1821 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1822 have an is_valid method.
1824 ** Breakpoints can now be sub-classed in Python, and in particular
1825 you may implement a 'stop' function that is executed each time
1826 the inferior reaches that breakpoint.
1828 ** New function gdb.lookup_global_symbol looks up a global symbol.
1830 ** GDB values in Python are now callable if the value represents a
1831 function. For example, if 'some_value' represents a function that
1832 takes two integer parameters and returns a value, you can call
1833 that function like so:
1835 result = some_value (10,20)
1837 ** Module gdb.types has been added.
1838 It contains a collection of utilities for working with gdb.Types objects:
1839 get_basic_type, has_field, make_enum_dict.
1841 ** Module gdb.printing has been added.
1842 It contains utilities for writing and registering pretty-printers.
1843 New classes: PrettyPrinter, SubPrettyPrinter,
1844 RegexpCollectionPrettyPrinter.
1845 New function: register_pretty_printer.
1847 ** New commands "info pretty-printers", "enable pretty-printer" and
1848 "disable pretty-printer" have been added.
1850 ** gdb.parameter("directories") is now available.
1852 ** New function gdb.newest_frame returns the newest frame in the
1855 ** The gdb.InferiorThread class has a new "name" attribute. This
1856 holds the thread's name.
1858 ** Python Support for Inferior events.
1859 Python scripts can add observers to be notified of events
1860 occurring in the process being debugged.
1861 The following events are currently supported:
1862 - gdb.events.cont Continue event.
1863 - gdb.events.exited Inferior exited event.
1864 - gdb.events.stop Signal received, and Breakpoint hit events.
1868 ** GDB now puts template parameters in scope when debugging in an
1869 instantiation. For example, if you have:
1871 template<int X> int func (void) { return X; }
1873 then if you step into func<5>, "print X" will show "5". This
1874 feature requires proper debuginfo support from the compiler; it
1875 was added to GCC 4.5.
1877 ** The motion commands "next", "finish", "until", and "advance" now
1878 work better when exceptions are thrown. In particular, GDB will
1879 no longer lose control of the inferior; instead, the GDB will
1880 stop the inferior at the point at which the exception is caught.
1881 This functionality requires a change in the exception handling
1882 code that was introduced in GCC 4.5.
1884 * GDB now follows GCC's rules on accessing volatile objects when
1885 reading or writing target state during expression evaluation.
1886 One notable difference to prior behavior is that "print x = 0"
1887 no longer generates a read of x; the value of the assignment is
1888 now always taken directly from the value being assigned.
1890 * GDB now has some support for using labels in the program's source in
1891 linespecs. For instance, you can use "advance label" to continue
1892 execution to a label.
1894 * GDB now has support for reading and writing a new .gdb_index
1895 section. This section holds a fast index of DWARF debugging
1896 information and can be used to greatly speed up GDB startup and
1897 operation. See the documentation for `save gdb-index' for details.
1899 * The "watch" command now accepts an optional "-location" argument.
1900 When used, this causes GDB to watch the memory referred to by the
1901 expression. Such a watchpoint is never deleted due to it going out
1904 * GDB now supports thread debugging of core dumps on GNU/Linux.
1906 GDB now activates thread debugging using the libthread_db library
1907 when debugging GNU/Linux core dumps, similarly to when debugging
1908 live processes. As a result, when debugging a core dump file, GDB
1909 is now able to display pthread_t ids of threads. For example, "info
1910 threads" shows the same output as when debugging the process when it
1911 was live. In earlier releases, you'd see something like this:
1914 * 1 LWP 6780 main () at main.c:10
1916 While now you see this:
1919 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1921 It is also now possible to inspect TLS variables when debugging core
1924 When debugging a core dump generated on a machine other than the one
1925 used to run GDB, you may need to point GDB at the correct
1926 libthread_db library with the "set libthread-db-search-path"
1927 command. See the user manual for more details on this command.
1929 * When natively debugging programs on PowerPC BookE processors running
1930 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1931 which stop execution of the inferior whenever it executes an instruction
1932 at any address within the specified range. See the "PowerPC Embedded"
1933 section in the user manual for more details.
1935 * New features in the GDB remote stub, GDBserver
1937 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1938 and i686 LynxOS (version 5.x).
1940 ** GDBserver is now supported on Blackfin Linux.
1942 * New native configurations
1944 ia64 HP-UX ia64-*-hpux*
1948 Analog Devices, Inc. Blackfin Processor bfin-*
1950 * Ada task switching is now supported on sparc-elf targets when
1951 debugging a program using the Ravenscar Profile. For more information,
1952 see the "Tasking Support when using the Ravenscar Profile" section
1953 in the GDB user manual.
1955 * Guile support was removed.
1957 * New features in the GNU simulator
1959 ** The --map-info flag lists all known core mappings.
1961 ** CFI flashes may be simulated via the "cfi" device.
1963 *** Changes in GDB 7.2
1965 * Shared library support for remote targets by default
1967 When GDB is configured for a generic, non-OS specific target, like
1968 for example, --target=arm-eabi or one of the many *-*-elf targets,
1969 GDB now queries remote stubs for loaded shared libraries using the
1970 `qXfer:libraries:read' packet. Previously, shared library support
1971 was always disabled for such configurations.
1975 ** Argument Dependent Lookup (ADL)
1977 In C++ ADL lookup directs function search to the namespaces of its
1978 arguments even if the namespace has not been imported.
1988 Here the compiler will search for `foo' in the namespace of 'b'
1989 and find A::foo. GDB now supports this. This construct is commonly
1990 used in the Standard Template Library for operators.
1992 ** Improved User Defined Operator Support
1994 In addition to member operators, GDB now supports lookup of operators
1995 defined in a namespace and imported with a `using' directive, operators
1996 defined in the global scope, operators imported implicitly from an
1997 anonymous namespace, and the ADL operators mentioned in the previous
1999 GDB now also supports proper overload resolution for all the previously
2000 mentioned flavors of operators.
2002 ** static const class members
2004 Printing of static const class members that are initialized in the
2005 class definition has been fixed.
2007 * Windows Thread Information Block access.
2009 On Windows targets, GDB now supports displaying the Windows Thread
2010 Information Block (TIB) structure. This structure is visible either
2011 by using the new command `info w32 thread-information-block' or, by
2012 dereferencing the new convenience variable named `$_tlb', a
2013 thread-specific pointer to the TIB. This feature is also supported
2014 when remote debugging using GDBserver.
2016 * Static tracepoints
2018 Static tracepoints are calls in the user program into a tracing
2019 library. One such library is a port of the LTTng kernel tracer to
2020 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2021 When debugging with GDBserver, GDB now supports combining the GDB
2022 tracepoint machinery with such libraries. For example: the user can
2023 use GDB to probe a static tracepoint marker (a call from the user
2024 program into the tracing library) with the new "strace" command (see
2025 "New commands" below). This creates a "static tracepoint" in the
2026 breakpoint list, that can be manipulated with the same feature set
2027 as fast and regular tracepoints. E.g., collect registers, local and
2028 global variables, collect trace state variables, and define
2029 tracepoint conditions. In addition, the user can collect extra
2030 static tracepoint marker specific data, by collecting the new
2031 $_sdata internal variable. When analyzing the trace buffer, you can
2032 inspect $_sdata like any other variable available to GDB. For more
2033 information, see the "Tracepoints" chapter in GDB user manual. New
2034 remote packets have been defined to support static tracepoints, see
2035 the "New remote packets" section below.
2037 * Better reconstruction of tracepoints after disconnected tracing
2039 GDB will attempt to download the original source form of tracepoint
2040 definitions when starting a trace run, and then will upload these
2041 upon reconnection to the target, resulting in a more accurate
2042 reconstruction of the tracepoints that are in use on the target.
2046 You can now exercise direct control over the ways that GDB can
2047 affect your program. For instance, you can disallow the setting of
2048 breakpoints, so that the program can run continuously (assuming
2049 non-stop mode). In addition, the "observer" variable is available
2050 to switch all of the different controls; in observer mode, GDB
2051 cannot affect the target's behavior at all, which is useful for
2052 tasks like diagnosing live systems in the field.
2054 * The new convenience variable $_thread holds the number of the
2057 * New remote packets
2061 Return the address of the Windows Thread Information Block of a given thread.
2065 In response to several of the tracepoint packets, the target may now
2066 also respond with a number of intermediate `qRelocInsn' request
2067 packets before the final result packet, to have GDB handle
2068 relocating an instruction to execute at a different address. This
2069 is particularly useful for stubs that support fast tracepoints. GDB
2070 reports support for this feature in the qSupported packet.
2074 List static tracepoint markers in the target program.
2078 List static tracepoint markers at a given address in the target
2081 qXfer:statictrace:read
2083 Read the static trace data collected (by a `collect $_sdata'
2084 tracepoint action). The remote stub reports support for this packet
2085 to gdb's qSupported query.
2089 Send the current settings of GDB's permission flags.
2093 Send part of the source (textual) form of a tracepoint definition,
2094 which includes location, conditional, and action list.
2096 * The source command now accepts a -s option to force searching for the
2097 script in the source search path even if the script name specifies
2100 * New features in the GDB remote stub, GDBserver
2102 - GDBserver now support tracepoints (including fast tracepoints, and
2103 static tracepoints). The feature is currently supported by the
2104 i386-linux and amd64-linux builds. See the "Tracepoints support
2105 in gdbserver" section in the manual for more information.
2107 GDBserver JIT compiles the tracepoint's conditional agent
2108 expression bytecode into native code whenever possible for low
2109 overhead dynamic tracepoints conditionals. For such tracepoints,
2110 an expression that examines program state is evaluated when the
2111 tracepoint is reached, in order to determine whether to capture
2112 trace data. If the condition is simple and false, processing the
2113 tracepoint finishes very quickly and no data is gathered.
2115 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2116 for static tracepoints support.
2118 - GDBserver now supports x86_64 Windows 64-bit debugging.
2120 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2121 it understands register description.
2123 * The --batch flag now disables pagination and queries.
2125 * X86 general purpose registers
2127 GDB now supports reading/writing byte, word and double-word x86
2128 general purpose registers directly. This means you can use, say,
2129 $ah or $ax to refer, respectively, to the byte register AH and
2130 16-bit word register AX that are actually portions of the 32-bit
2131 register EAX or 64-bit register RAX.
2133 * The `commands' command now accepts a range of breakpoints to modify.
2134 A plain `commands' following a command that creates multiple
2135 breakpoints affects all the breakpoints set by that command. This
2136 applies to breakpoints set by `rbreak', and also applies when a
2137 single `break' command creates multiple breakpoints (e.g.,
2138 breakpoints on overloaded c++ functions).
2140 * The `rbreak' command now accepts a filename specification as part of
2141 its argument, limiting the functions selected by the regex to those
2142 in the specified file.
2144 * Support for remote debugging Windows and SymbianOS shared libraries
2145 from Unix hosts has been improved. Non Windows GDB builds now can
2146 understand target reported file names that follow MS-DOS based file
2147 system semantics, such as file names that include drive letters and
2148 use the backslash character as directory separator. This makes it
2149 possible to transparently use the "set sysroot" and "set
2150 solib-search-path" on Unix hosts to point as host copies of the
2151 target's shared libraries. See the new command "set
2152 target-file-system-kind" described below, and the "Commands to
2153 specify files" section in the user manual for more information.
2157 eval template, expressions...
2158 Convert the values of one or more expressions under the control
2159 of the string template to a command line, and call it.
2161 set target-file-system-kind unix|dos-based|auto
2162 show target-file-system-kind
2163 Set or show the assumed file system kind for target reported file
2166 save breakpoints <filename>
2167 Save all current breakpoint definitions to a file suitable for use
2168 in a later debugging session. To read the saved breakpoint
2169 definitions, use the `source' command.
2171 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2174 info static-tracepoint-markers
2175 Display information about static tracepoint markers in the target.
2177 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2178 Define a static tracepoint by probing a marker at the given
2179 function, line, address, or marker ID.
2183 Enable and disable observer mode.
2185 set may-write-registers on|off
2186 set may-write-memory on|off
2187 set may-insert-breakpoints on|off
2188 set may-insert-tracepoints on|off
2189 set may-insert-fast-tracepoints on|off
2190 set may-interrupt on|off
2191 Set individual permissions for GDB effects on the target. Note that
2192 some of these settings can have undesirable or surprising
2193 consequences, particularly when changed in the middle of a session.
2194 For instance, disabling the writing of memory can prevent
2195 breakpoints from being inserted, cause single-stepping to fail, or
2196 even crash your program, if you disable after breakpoints have been
2197 inserted. However, GDB should not crash.
2199 set record memory-query on|off
2200 show record memory-query
2201 Control whether to stop the inferior if memory changes caused
2202 by an instruction cannot be recorded.
2207 The disassemble command now supports "start,+length" form of two arguments.
2211 ** GDB now provides a new directory location, called the python directory,
2212 where Python scripts written for GDB can be installed. The location
2213 of that directory is <data-directory>/python, where <data-directory>
2214 is the GDB data directory. For more details, see section `Scripting
2215 GDB using Python' in the manual.
2217 ** The GDB Python API now has access to breakpoints, symbols, symbol
2218 tables, program spaces, inferiors, threads and frame's code blocks.
2219 Additionally, GDB Parameters can now be created from the API, and
2220 manipulated via set/show in the CLI.
2222 ** New functions gdb.target_charset, gdb.target_wide_charset,
2223 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2225 ** New exception gdb.GdbError.
2227 ** Pretty-printers are now also looked up in the current program space.
2229 ** Pretty-printers can now be individually enabled and disabled.
2231 ** GDB now looks for names of Python scripts to auto-load in a
2232 special section named `.debug_gdb_scripts', in addition to looking
2233 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2235 * Tracepoint actions were unified with breakpoint commands. In particular,
2236 there are no longer differences in "info break" output for breakpoints and
2237 tracepoints and the "commands" command can be used for both tracepoints and
2238 regular breakpoints.
2242 ARM Symbian arm*-*-symbianelf*
2244 * D language support.
2245 GDB now supports debugging programs written in the D programming
2248 * GDB now supports the extended ptrace interface for PowerPC which is
2249 available since Linux kernel version 2.6.34. This automatically enables
2250 any hardware breakpoints and additional hardware watchpoints available in
2251 the processor. The old ptrace interface exposes just one hardware
2252 watchpoint and no hardware breakpoints.
2254 * GDB is now able to use the Data Value Compare (DVC) register available on
2255 embedded PowerPC processors to implement in hardware simple watchpoint
2256 conditions of the form:
2258 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2260 This works in native GDB running on Linux kernels with the extended ptrace
2261 interface mentioned above.
2263 *** Changes in GDB 7.1
2267 ** Namespace Support
2269 GDB now supports importing of namespaces in C++. This enables the
2270 user to inspect variables from imported namespaces. Support for
2271 namepace aliasing has also been added. So, if a namespace is
2272 aliased in the current scope (e.g. namepace C=A; ) the user can
2273 print variables using the alias (e.g. (gdb) print C::x).
2277 All known bugs relating to the printing of virtual base class were
2278 fixed. It is now possible to call overloaded static methods using a
2283 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2284 and reinterpret_cast<> are now handled by the C++ expression parser.
2288 Xilinx MicroBlaze microblaze-*-*
2293 Xilinx MicroBlaze microblaze
2296 * Multi-program debugging.
2298 GDB now has support for multi-program (a.k.a. multi-executable or
2299 multi-exec) debugging. This allows for debugging multiple inferiors
2300 simultaneously each running a different program under the same GDB
2301 session. See "Debugging Multiple Inferiors and Programs" in the
2302 manual for more information. This implied some user visible changes
2303 in the multi-inferior support. For example, "info inferiors" now
2304 lists inferiors that are not running yet or that have exited
2305 already. See also "New commands" and "New options" below.
2307 * New tracing features
2309 GDB's tracepoint facility now includes several new features:
2311 ** Trace state variables
2313 GDB tracepoints now include support for trace state variables, which
2314 are variables managed by the target agent during a tracing
2315 experiment. They are useful for tracepoints that trigger each
2316 other, so for instance one tracepoint can count hits in a variable,
2317 and then a second tracepoint has a condition that is true when the
2318 count reaches a particular value. Trace state variables share the
2319 $-syntax of GDB convenience variables, and can appear in both
2320 tracepoint actions and condition expressions. Use the "tvariable"
2321 command to create, and "info tvariables" to view; see "Trace State
2322 Variables" in the manual for more detail.
2326 GDB now includes an option for defining fast tracepoints, which
2327 targets may implement more efficiently, such as by installing a jump
2328 into the target agent rather than a trap instruction. The resulting
2329 speedup can be by two orders of magnitude or more, although the
2330 tradeoff is that some program locations on some target architectures
2331 might not allow fast tracepoint installation, for instance if the
2332 instruction to be replaced is shorter than the jump. To request a
2333 fast tracepoint, use the "ftrace" command, with syntax identical to
2334 the regular trace command.
2336 ** Disconnected tracing
2338 It is now possible to detach GDB from the target while it is running
2339 a trace experiment, then reconnect later to see how the experiment
2340 is going. In addition, a new variable disconnected-tracing lets you
2341 tell the target agent whether to continue running a trace if the
2342 connection is lost unexpectedly.
2346 GDB now has the ability to save the trace buffer into a file, and
2347 then use that file as a target, similarly to you can do with
2348 corefiles. You can select trace frames, print data that was
2349 collected in them, and use tstatus to display the state of the
2350 tracing run at the moment that it was saved. To create a trace
2351 file, use "tsave <filename>", and to use it, do "target tfile
2354 ** Circular trace buffer
2356 You can ask the target agent to handle the trace buffer as a
2357 circular buffer, discarding the oldest trace frames to make room for
2358 newer ones, by setting circular-trace-buffer to on. This feature may
2359 not be available for all target agents.
2364 The disassemble command, when invoked with two arguments, now requires
2365 the arguments to be comma-separated.
2368 The info variables command now displays variable definitions. Files
2369 which only declare a variable are not shown.
2372 The source command is now capable of sourcing Python scripts.
2373 This feature is dependent on the debugger being build with Python
2376 Related to this enhancement is also the introduction of a new command
2377 "set script-extension" (see below).
2379 * New commands (for set/show, see "New options" below)
2381 record save [<FILENAME>]
2382 Save a file (in core file format) containing the process record
2383 execution log for replay debugging at a later time.
2385 record restore <FILENAME>
2386 Restore the process record execution log that was saved at an
2387 earlier time, for replay debugging.
2389 add-inferior [-copies <N>] [-exec <FILENAME>]
2392 clone-inferior [-copies <N>] [ID]
2393 Make a new inferior ready to execute the same program another
2394 inferior has loaded.
2399 maint info program-spaces
2400 List the program spaces loaded into GDB.
2402 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2403 show remote interrupt-sequence
2404 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2405 as the sequence to the remote target in order to interrupt the execution.
2406 Ctrl-C is a default. Some system prefers BREAK which is high level of
2407 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2408 Magic SysRq g. It is BREAK signal and character 'g'.
2410 set remote interrupt-on-connect [on | off]
2411 show remote interrupt-on-connect
2412 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2413 remote target when gdb connects to it. This is needed when you debug
2416 set remotebreak [on | off]
2418 Deprecated. Use "set/show remote interrupt-sequence" instead.
2420 tvariable $NAME [ = EXP ]
2421 Create or modify a trace state variable.
2424 List trace state variables and their values.
2426 delete tvariable $NAME ...
2427 Delete one or more trace state variables.
2430 Evaluate the given expressions without collecting anything into the
2431 trace buffer. (Valid in tracepoint actions only.)
2433 ftrace FN / FILE:LINE / *ADDR
2434 Define a fast tracepoint at the given function, line, or address.
2436 * New expression syntax
2438 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2439 GDB now parses 0b101010 identically with 42.
2443 set follow-exec-mode new|same
2444 show follow-exec-mode
2445 Control whether GDB reuses the same inferior across an exec call or
2446 creates a new one. This is useful to be able to restart the old
2447 executable after the inferior having done an exec call.
2449 set default-collect EXPR, ...
2450 show default-collect
2451 Define a list of expressions to be collected at each tracepoint.
2452 This is a useful way to ensure essential items are not overlooked,
2453 such as registers or a critical global variable.
2455 set disconnected-tracing
2456 show disconnected-tracing
2457 If set to 1, the target is instructed to continue tracing if it
2458 loses its connection to GDB. If 0, the target is to stop tracing
2461 set circular-trace-buffer
2462 show circular-trace-buffer
2463 If set to on, the target is instructed to use a circular trace buffer
2464 and discard the oldest trace frames instead of stopping the trace due
2465 to a full trace buffer. If set to off, the trace stops when the buffer
2466 fills up. Some targets may not support this.
2468 set script-extension off|soft|strict
2469 show script-extension
2470 If set to "off", the debugger does not perform any script language
2471 recognition, and all sourced files are assumed to be GDB scripts.
2472 If set to "soft" (the default), files are sourced according to
2473 filename extension, falling back to GDB scripts if the first
2475 If set to "strict", files are sourced according to filename extension.
2477 set ada trust-PAD-over-XVS on|off
2478 show ada trust-PAD-over-XVS
2479 If off, activate a workaround against a bug in the debugging information
2480 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2481 the GCC sources for more information about the GNAT encoding and
2482 PAD types in particular). It is always safe to set this option to
2483 off, but this introduces a slight performance penalty. The default
2486 * Python API Improvements
2488 ** GDB provides the new class gdb.LazyString. This is useful in
2489 some pretty-printing cases. The new method gdb.Value.lazy_string
2490 provides a simple way to create objects of this type.
2492 ** The fields returned by gdb.Type.fields now have an
2493 `is_base_class' attribute.
2495 ** The new method gdb.Type.range returns the range of an array type.
2497 ** The new method gdb.parse_and_eval can be used to parse and
2498 evaluate an expression.
2500 * New remote packets
2503 Define a trace state variable.
2506 Get the current value of a trace state variable.
2509 Set desired tracing behavior upon disconnection.
2512 Set the trace buffer to be linear or circular.
2515 Get data about the tracepoints currently in use.
2519 Process record now works correctly with hardware watchpoints.
2521 Multiple bug fixes have been made to the mips-irix port, making it
2522 much more reliable. In particular:
2523 - Debugging threaded applications is now possible again. Previously,
2524 GDB would hang while starting the program, or while waiting for
2525 the program to stop at a breakpoint.
2526 - Attaching to a running process no longer hangs.
2527 - An error occurring while loading a core file has been fixed.
2528 - Changing the value of the PC register now works again. This fixes
2529 problems observed when using the "jump" command, or when calling
2530 a function from GDB, or even when assigning a new value to $pc.
2531 - With the "finish" and "return" commands, the return value for functions
2532 returning a small array is now correctly printed.
2533 - It is now possible to break on shared library code which gets executed
2534 during a shared library init phase (code executed while executing
2535 their .init section). Previously, the breakpoint would have no effect.
2536 - GDB is now able to backtrace through the signal handler for
2537 non-threaded programs.
2539 PIE (Position Independent Executable) programs debugging is now supported.
2540 This includes debugging execution of PIC (Position Independent Code) shared
2541 libraries although for that, it should be possible to run such libraries as an
2544 *** Changes in GDB 7.0
2546 * GDB now has an interface for JIT compilation. Applications that
2547 dynamically generate code can create symbol files in memory and register
2548 them with GDB. For users, the feature should work transparently, and
2549 for JIT developers, the interface is documented in the GDB manual in the
2550 "JIT Compilation Interface" chapter.
2552 * Tracepoints may now be conditional. The syntax is as for
2553 breakpoints; either an "if" clause appended to the "trace" command,
2554 or the "condition" command is available. GDB sends the condition to
2555 the target for evaluation using the same bytecode format as is used
2556 for tracepoint actions.
2558 * The disassemble command now supports: an optional /r modifier, print the
2559 raw instructions in hex as well as in symbolic form, and an optional /m
2560 modifier to print mixed source+assembly.
2562 * Process record and replay
2564 In a architecture environment that supports ``process record and
2565 replay'', ``process record and replay'' target can record a log of
2566 the process execution, and replay it with both forward and reverse
2569 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2570 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2571 set execution-direction {forward|reverse}, for targets that support
2574 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2575 feature is available with a native GDB running on kernel version
2578 * GDB now has support for multi-byte and wide character sets on the
2579 target. Strings whose character type is wchar_t, char16_t, or
2580 char32_t are now correctly printed. GDB supports wide- and unicode-
2581 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2582 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2583 `printf'. This feature requires iconv to work properly; if your
2584 system does not have a working iconv, GDB can use GNU libiconv. See
2585 the installation instructions for more information.
2587 * GDB now supports automatic retrieval of shared library files from
2588 remote targets. To use this feature, specify a system root that begins
2589 with the `remote:' prefix, either via the `set sysroot' command or via
2590 the `--with-sysroot' configure-time option.
2592 * "info sharedlibrary" now takes an optional regex of libraries to show,
2593 and it now reports if a shared library has no debugging information.
2595 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2596 now complete on file names.
2598 * When completing in expressions, gdb will attempt to limit
2599 completions to allowable structure or union fields, where appropriate.
2600 For instance, consider:
2602 # struct example { int f1; double f2; };
2603 # struct example variable;
2606 If the user types TAB at the end of this command line, the available
2607 completions will be "f1" and "f2".
2609 * Inlined functions are now supported. They show up in backtraces, and
2610 the "step", "next", and "finish" commands handle them automatically.
2612 * GDB now supports the token-splicing (##) and stringification (#)
2613 operators when expanding macros. It also supports variable-arity
2616 * GDB now supports inspecting extra signal information, exported by
2617 the new $_siginfo convenience variable. The feature is currently
2618 implemented on linux ARM, i386 and amd64.
2620 * GDB can now display the VFP floating point registers and NEON vector
2621 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2622 can provide these registers (requires Linux 2.6.30 or later). Remote
2623 and simulator targets may also provide them.
2625 * New remote packets
2628 Search memory for a sequence of bytes.
2631 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2632 operation over reliable transport links. Use of this packet is
2633 controlled by the `set remote noack-packet' command.
2636 Kill the process with the specified process ID. Use this in preference
2637 to `k' when multiprocess protocol extensions are supported.
2640 Obtains additional operating system information
2644 Read or write additional signal information.
2646 * Removed remote protocol undocumented extension
2648 An undocumented extension to the remote protocol's `S' stop reply
2649 packet that permited the stub to pass a process id was removed.
2650 Remote servers should use the `T' stop reply packet instead.
2652 * GDB now supports multiple function calling conventions according to the
2653 DWARF-2 DW_AT_calling_convention function attribute.
2655 * The SH target utilizes the aforementioned change to distinguish between gcc
2656 and Renesas calling convention. It also adds the new CLI commands
2657 `set/show sh calling-convention'.
2659 * GDB can now read compressed debug sections, as produced by GNU gold
2660 with the --compress-debug-sections=zlib flag.
2662 * 64-bit core files are now supported on AIX.
2664 * Thread switching is now supported on Tru64.
2666 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2667 which will be allocated using malloc later in program execution.
2669 * The qXfer:libraries:read remote procotol packet now allows passing a
2670 list of section offsets.
2672 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2673 conditions handling signals delivered during attach or thread creation
2674 have also been fixed.
2676 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2677 From the user's standpoint, all unqualified instances of True and False
2678 are treated as the standard definitions, regardless of context.
2680 * GDB now parses C++ symbol and type names more flexibly. For
2683 template<typename T> class C { };
2686 GDB will now correctly handle all of:
2688 ptype C<char const *>
2689 ptype C<char const*>
2690 ptype C<const char *>
2691 ptype C<const char*>
2693 * New features in the GDB remote stub, gdbserver
2695 - The "--wrapper" command-line argument tells gdbserver to use a
2696 wrapper program to launch programs for debugging.
2698 - On PowerPC and S/390 targets, it is now possible to use a single
2699 gdbserver executable to debug both 32-bit and 64-bit programs.
2700 (This requires gdbserver itself to be built as a 64-bit executable.)
2702 - gdbserver uses the new noack protocol mode for TCP connections to
2703 reduce communications latency, if also supported and enabled in GDB.
2705 - Support for the sparc64-linux-gnu target is now included in
2708 - The amd64-linux build of gdbserver now supports debugging both
2709 32-bit and 64-bit programs.
2711 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2712 now support hardware watchpoints, and will use them automatically
2717 GDB now has support for scripting using Python. Whether this is
2718 available is determined at configure time.
2720 New GDB commands can now be written in Python.
2722 * Ada tasking support
2724 Ada tasks can now be inspected in GDB. The following commands have
2728 Print the list of Ada tasks.
2730 Print detailed information about task number N.
2732 Print the task number of the current task.
2734 Switch the context of debugging to task number N.
2736 * Support for user-defined prefixed commands. The "define" command can
2737 add new commands to existing prefixes, e.g. "target".
2739 * Multi-inferior, multi-process debugging.
2741 GDB now has generalized support for multi-inferior debugging. See
2742 "Debugging Multiple Inferiors" in the manual for more information.
2743 Although availability still depends on target support, the command
2744 set is more uniform now. The GNU/Linux specific multi-forks support
2745 has been migrated to this new framework. This implied some user
2746 visible changes; see "New commands" and also "Removed commands"
2749 * Target descriptions can now describe the target OS ABI. See the
2750 "Target Description Format" section in the user manual for more
2753 * Target descriptions can now describe "compatible" architectures
2754 to indicate that the target can execute applications for a different
2755 architecture in addition to those for the main target architecture.
2756 See the "Target Description Format" section in the user manual for
2759 * Multi-architecture debugging.
2761 GDB now includes general supports for debugging applications on
2762 hybrid systems that use more than one single processor architecture
2763 at the same time. Each such hybrid architecture still requires
2764 specific support to be added. The only hybrid architecture supported
2765 in this version of GDB is the Cell Broadband Engine.
2767 * GDB now supports integrated debugging of Cell/B.E. applications that
2768 use both the PPU and SPU architectures. To enable support for hybrid
2769 Cell/B.E. debugging, you need to configure GDB to support both the
2770 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2771 --enable-targets configure option.
2773 * Non-stop mode debugging.
2775 For some targets, GDB now supports an optional mode of operation in
2776 which you can examine stopped threads while other threads continue
2777 to execute freely. This is referred to as non-stop mode, with the
2778 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2779 section in the user manual for more information.
2781 To be able to support remote non-stop debugging, a remote stub needs
2782 to implement the non-stop mode remote protocol extensions, as
2783 described in the "Remote Non-Stop" section of the user manual. The
2784 GDB remote stub, gdbserver, has been adjusted to support these
2785 extensions on linux targets.
2787 * New commands (for set/show, see "New options" below)
2789 catch syscall [NAME(S) | NUMBER(S)]
2790 Catch system calls. Arguments, which should be names of system
2791 calls or their numbers, mean catch only those syscalls. Without
2792 arguments, every syscall will be caught. When the inferior issues
2793 any of the specified syscalls, GDB will stop and announce the system
2794 call, both when it is called and when its call returns. This
2795 feature is currently available with a native GDB running on the
2796 Linux Kernel, under the following architectures: x86, x86_64,
2797 PowerPC and PowerPC64.
2799 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2801 Search memory for a sequence of bytes.
2803 maint set python print-stack
2804 maint show python print-stack
2805 Show a stack trace when an error is encountered in a Python script.
2808 Invoke CODE by passing it to the Python interpreter.
2813 These allow macros to be defined, undefined, and listed
2817 Show operating system information about processes.
2820 List the inferiors currently under GDB's control.
2823 Switch focus to inferior number NUM.
2826 Detach from inferior number NUM.
2829 Kill inferior number NUM.
2833 set spu stop-on-load
2834 show spu stop-on-load
2835 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2837 set spu auto-flush-cache
2838 show spu auto-flush-cache
2839 Control whether to automatically flush the software-managed cache
2840 during Cell/B.E. debugging.
2842 set sh calling-convention
2843 show sh calling-convention
2844 Control the calling convention used when calling SH target functions.
2847 show debug timestamp
2848 Control display of timestamps with GDB debugging output.
2850 set disassemble-next-line
2851 show disassemble-next-line
2852 Control display of disassembled source lines or instructions when
2855 set remote noack-packet
2856 show remote noack-packet
2857 Set/show the use of remote protocol QStartNoAckMode packet. See above
2858 under "New remote packets."
2860 set remote query-attached-packet
2861 show remote query-attached-packet
2862 Control use of remote protocol `qAttached' (query-attached) packet.
2864 set remote read-siginfo-object
2865 show remote read-siginfo-object
2866 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2869 set remote write-siginfo-object
2870 show remote write-siginfo-object
2871 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2874 set remote reverse-continue
2875 show remote reverse-continue
2876 Control use of remote protocol 'bc' (reverse-continue) packet.
2878 set remote reverse-step
2879 show remote reverse-step
2880 Control use of remote protocol 'bs' (reverse-step) packet.
2882 set displaced-stepping
2883 show displaced-stepping
2884 Control displaced stepping mode. Displaced stepping is a way to
2885 single-step over breakpoints without removing them from the debuggee.
2886 Also known as "out-of-line single-stepping".
2889 show debug displaced
2890 Control display of debugging info for displaced stepping.
2892 maint set internal-error
2893 maint show internal-error
2894 Control what GDB does when an internal error is detected.
2896 maint set internal-warning
2897 maint show internal-warning
2898 Control what GDB does when an internal warning is detected.
2903 Use a wrapper program to launch programs for debugging.
2905 set multiple-symbols (all|ask|cancel)
2906 show multiple-symbols
2907 The value of this variable can be changed to adjust the debugger behavior
2908 when an expression or a breakpoint location contains an ambiguous symbol
2909 name (an overloaded function name, for instance).
2911 set breakpoint always-inserted
2912 show breakpoint always-inserted
2913 Keep breakpoints always inserted in the target, as opposed to inserting
2914 them when resuming the target, and removing them when the target stops.
2915 This option can improve debugger performance on slow remote targets.
2917 set arm fallback-mode (arm|thumb|auto)
2918 show arm fallback-mode
2919 set arm force-mode (arm|thumb|auto)
2921 These commands control how ARM GDB determines whether instructions
2922 are ARM or Thumb. The default for both settings is auto, which uses
2923 the current CPSR value for instructions without symbols; previous
2924 versions of GDB behaved as if "set arm fallback-mode arm".
2926 set disable-randomization
2927 show disable-randomization
2928 Standalone programs run with the virtual address space randomization enabled
2929 by default on some platforms. This option keeps the addresses stable across
2930 multiple debugging sessions.
2934 Control whether other threads are stopped or not when some thread hits
2939 Requests that asynchronous execution is enabled in the target, if available.
2940 In this case, it's possible to resume target in the background, and interact
2941 with GDB while the target is running. "show target-async" displays the
2942 current state of asynchronous execution of the target.
2944 set target-wide-charset
2945 show target-wide-charset
2946 The target-wide-charset is the name of the character set that GDB
2947 uses when printing characters whose type is wchar_t.
2949 set tcp auto-retry (on|off)
2951 set tcp connect-timeout
2952 show tcp connect-timeout
2953 These commands allow GDB to retry failed TCP connections to a remote stub
2954 with a specified timeout period; this is useful if the stub is launched
2955 in parallel with GDB but may not be ready to accept connections immediately.
2957 set libthread-db-search-path
2958 show libthread-db-search-path
2959 Control list of directories which GDB will search for appropriate
2962 set schedule-multiple (on|off)
2963 show schedule-multiple
2964 Allow GDB to resume all threads of all processes or only threads of
2965 the current process.
2969 Use more aggressive caching for accesses to the stack. This improves
2970 performance of remote debugging (particularly backtraces) without
2971 affecting correctness.
2973 set interactive-mode (on|off|auto)
2974 show interactive-mode
2975 Control whether GDB runs in interactive mode (on) or not (off).
2976 When in interactive mode, GDB waits for the user to answer all
2977 queries. Otherwise, GDB does not wait and assumes the default
2978 answer. When set to auto (the default), GDB determines which
2979 mode to use based on the stdin settings.
2984 For program forks, this is replaced by the new more generic `info
2985 inferiors' command. To list checkpoints, you can still use the
2986 `info checkpoints' command, which was an alias for the `info forks'
2990 Replaced by the new `inferior' command. To switch between
2991 checkpoints, you can still use the `restart' command, which was an
2992 alias for the `fork' command.
2995 This is removed, since some targets don't have a notion of
2996 processes. To switch between processes, you can still use the
2997 `inferior' command using GDB's own inferior number.
3000 For program forks, this is replaced by the new more generic `kill
3001 inferior' command. To delete a checkpoint, you can still use the
3002 `delete checkpoint' command, which was an alias for the `delete
3006 For program forks, this is replaced by the new more generic `detach
3007 inferior' command. To detach a checkpoint, you can still use the
3008 `detach checkpoint' command, which was an alias for the `detach
3011 * New native configurations
3013 x86/x86_64 Darwin i[34567]86-*-darwin*
3015 x86_64 MinGW x86_64-*-mingw*
3019 Lattice Mico32 lm32-*
3020 x86 DICOS i[34567]86-*-dicos*
3021 x86_64 DICOS x86_64-*-dicos*
3024 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3025 (mingw32ce) debugging.
3031 These commands were actually not implemented on any target.
3033 *** Changes in GDB 6.8
3035 * New native configurations
3037 NetBSD/hppa hppa*-*netbsd*
3038 Xtensa GNU/Linux xtensa*-*-linux*
3042 NetBSD/hppa hppa*-*-netbsd*
3043 Xtensa GNU/Lunux xtensa*-*-linux*
3045 * Change in command line behavior -- corefiles vs. process ids.
3047 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3048 attaching to process NUMBER fails, GDB no longer attempts to open a
3049 core file named NUMBER. Attaching to a program using the -c option
3050 is no longer supported. Instead, use the '-p' or '--pid' options.
3052 * GDB can now be built as a native debugger for debugging Windows x86
3053 (mingw32) Portable Executable (PE) programs.
3055 * Pending breakpoints no longer change their number when their address
3058 * GDB now supports breakpoints with multiple locations,
3059 including breakpoints on C++ constructors, inside C++ templates,
3060 and in inlined functions.
3062 * GDB's ability to debug optimized code has been improved. GDB more
3063 accurately identifies function bodies and lexical blocks that occupy
3064 more than one contiguous range of addresses.
3066 * Target descriptions can now describe registers for PowerPC.
3068 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3069 registers on PowerPC targets.
3071 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3072 targets even when the libthread_db library is not available.
3074 * The GDB remote stub, gdbserver, now supports the new file transfer
3075 commands (remote put, remote get, and remote delete).
3077 * The GDB remote stub, gdbserver, now supports run and attach in
3078 extended-remote mode.
3080 * hppa*64*-*-hpux11* target broken
3081 The debugger is unable to start a program and fails with the following
3082 error: "Error trying to get information about dynamic linker".
3083 The gdb-6.7 release is also affected.
3085 * GDB now supports the --enable-targets= configure option to allow
3086 building a single GDB executable that supports multiple remote
3087 target architectures.
3089 * GDB now supports debugging C and C++ programs which use the
3090 Decimal Floating Point extension. In addition, the PowerPC target
3091 now has a set of pseudo-registers to inspect decimal float values
3092 stored in two consecutive float registers.
3094 * The -break-insert MI command can optionally create pending
3097 * Improved support for debugging Ada
3098 Many improvements to the Ada language support have been made. These
3100 - Better support for Ada2005 interface types
3101 - Improved handling of arrays and slices in general
3102 - Better support for Taft-amendment types
3103 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3105 - Improved command completion in Ada
3108 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3113 set print frame-arguments (all|scalars|none)
3114 show print frame-arguments
3115 The value of this variable can be changed to control which argument
3116 values should be printed by the debugger when displaying a frame.
3121 Transfer files to and from a remote target, and delete remote files.
3128 Transfer files to and from a remote target, and delete remote files.
3130 * New remote packets
3137 Open, close, read, write, and delete files on the remote system.
3140 Attach to an existing process on the remote system, in extended-remote
3144 Run a new process on the remote system, in extended-remote mode.
3146 *** Changes in GDB 6.7
3148 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3149 bfd, libiberty and opcodes, as revealed by static analysis donated by
3150 Coverity, Inc. (http://scan.coverity.com).
3152 * When looking up multiply-defined global symbols, GDB will now prefer the
3153 symbol definition in the current shared library if it was built using the
3154 -Bsymbolic linker option.
3156 * When the Text User Interface (TUI) is not configured, GDB will now
3157 recognize the -tui command-line option and print a message that the TUI
3160 * The GDB remote stub, gdbserver, now has lower overhead for high
3161 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3163 * GDB for MIPS targets now autodetects whether a remote target provides
3164 32-bit or 64-bit register values.
3166 * Support for C++ member pointers has been improved.
3168 * GDB now understands XML target descriptions, which specify the
3169 target's overall architecture. GDB can read a description from
3170 a local file or over the remote serial protocol.
3172 * Vectors of single-byte data use a new integer type which is not
3173 automatically displayed as character or string data.
3175 * The /s format now works with the print command. It displays
3176 arrays of single-byte integers and pointers to single-byte integers
3179 * Target descriptions can now describe target-specific registers,
3180 for architectures which have implemented the support (currently
3181 only ARM, M68K, and MIPS).
3183 * GDB and the GDB remote stub, gdbserver, now support the XScale
3186 * The GDB remote stub, gdbserver, has been updated to support
3187 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3188 has been rewritten to use the standard GDB remote protocol.
3190 * GDB can now step into C++ functions which are called through thunks.
3192 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3194 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3195 layout. It also supports a TextSeg= and DataSeg= response when only
3196 segment base addresses (rather than offsets) are available.
3198 * The /i format now outputs any trailing branch delay slot instructions
3199 immediately following the last instruction within the count specified.
3201 * The GDB remote protocol "T" stop reply packet now supports a
3202 "library" response. Combined with the new "qXfer:libraries:read"
3203 packet, this response allows GDB to debug shared libraries on targets
3204 where the operating system manages the list of loaded libraries (e.g.
3205 Windows and SymbianOS).
3207 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3208 (DLLs) on Windows and Windows CE targets.
3210 * GDB now supports a faster verification that a .debug file matches its binary
3211 according to its build-id signature, if the signature is present.
3217 Enable or disable hardware flow control (RTS/CTS) on the serial port
3218 when debugging using remote targets.
3220 set mem inaccessible-by-default
3221 show mem inaccessible-by-default
3222 If the target supplies a memory map, for instance via the remote
3223 protocol's "qXfer:memory-map:read" packet, setting this variable
3224 prevents GDB from accessing memory outside the memory map. This
3225 is useful for targets with memory mapped registers or which react
3226 badly to accesses of unmapped address space.
3228 set breakpoint auto-hw
3229 show breakpoint auto-hw
3230 If the target supplies a memory map, for instance via the remote
3231 protocol's "qXfer:memory-map:read" packet, setting this variable
3232 lets GDB use hardware breakpoints automatically for memory regions
3233 where it can not use software breakpoints. This covers both the
3234 "break" command and internal breakpoints used for other commands
3235 including "next" and "finish".
3238 catch exception unhandled
3239 Stop the program execution when Ada exceptions are raised.
3242 Stop the program execution when an Ada assertion failed.
3246 Set an alternate system root for target files. This is a more
3247 general version of "set solib-absolute-prefix", which is now
3248 an alias to "set sysroot".
3251 Provide extended SPU facility status information. This set of
3252 commands is available only when debugging the Cell/B.E. SPU
3255 * New native configurations
3257 OpenBSD/sh sh*-*openbsd*
3260 unset tdesc filename
3262 Use the specified local file as an XML target description, and do
3263 not query the target for its built-in description.
3267 OpenBSD/sh sh*-*-openbsd*
3268 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3269 Toshiba Media Processor mep-elf
3271 * New remote packets
3274 Ignore the specified signals; pass them directly to the debugged program
3275 without stopping other threads or reporting them to GDB.
3277 qXfer:features:read:
3278 Read an XML target description from the target, which describes its
3283 Read or write contents of an spufs file on the target system. These
3284 packets are available only on the Cell/B.E. SPU architecture.
3286 qXfer:libraries:read:
3287 Report the loaded shared libraries. Combined with new "T" packet
3288 response, this packet allows GDB to debug shared libraries on
3289 targets where the operating system manages the list of loaded
3290 libraries (e.g. Windows and SymbianOS).
3294 Support for these obsolete configurations has been removed.
3302 i[34567]86-*-lynxos*
3303 i[34567]86-*-netware*
3304 i[34567]86-*-sco3.2v5*
3305 i[34567]86-*-sco3.2v4*
3307 i[34567]86-*-sysv4.2*
3310 i[34567]86-*-unixware2*
3311 i[34567]86-*-unixware*
3320 * Other removed features
3327 Various m68k-only ROM monitors.
3334 Various Renesas ROM monitors and debugging interfaces for SH and
3339 Support for a Macraigor serial interface to on-chip debugging.
3340 GDB does not directly support the newer parallel or USB
3345 A debug information format. The predecessor to DWARF 2 and
3346 DWARF 3, which are still supported.
3348 Support for the HP aCC compiler on HP-UX/PA-RISC
3350 SOM-encapsulated symbolic debugging information, automatic
3351 invocation of pxdb, and the aCC custom C++ ABI. This does not
3352 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3353 with aCC can still be debugged on an assembly level.
3355 MIPS ".pdr" sections
3357 A MIPS-specific format used to describe stack frame layout
3358 in debugging information.
3362 GDB could work with an older version of Guile to debug
3363 the interpreter and Scheme programs running in it.
3365 set mips stack-arg-size
3366 set mips saved-gpreg-size
3368 Use "set mips abi" to control parameter passing for MIPS.
3370 *** Changes in GDB 6.6
3375 Cell Broadband Engine SPU spu-elf
3377 * GDB can now be configured as a cross-debugger targeting native Windows
3378 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3379 running on a Windows system over TCP/IP to debug Windows programs.
3381 * The GDB remote stub, gdbserver, has been updated to support Windows and
3382 Cygwin debugging. Both single-threaded and multi-threaded programs are
3385 * The "set trust-readonly-sections" command works again. This command was
3386 broken in GDB 6.3, 6.4, and 6.5.
3388 * The "load" command now supports writing to flash memory, if the remote
3389 stub provides the required support.
3391 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3392 longer requires symbolic debug information (e.g. DWARF-2).
3397 unset substitute-path
3398 show substitute-path
3399 Manage a list of substitution rules that GDB uses to rewrite the name
3400 of the directories where the sources are located. This can be useful
3401 for instance when the sources were moved to a different location
3402 between compilation and debugging.
3406 Print each CLI command as it is executed. Each command is prefixed with
3407 a number of `+' symbols representing the nesting depth.
3408 The source command now has a `-v' option to enable the same feature.
3412 The ARM Demon monitor support (RDP protocol, "target rdp").
3414 Kernel Object Display, an embedded debugging feature which only worked with
3415 an obsolete version of Cisco IOS.
3417 The 'set download-write-size' and 'show download-write-size' commands.
3419 * New remote packets
3422 Tell a stub about GDB client features, and request remote target features.
3423 The first feature implemented is PacketSize, which allows the target to
3424 specify the size of packets it can handle - to minimize the number of
3425 packets required and improve performance when connected to a remote
3429 Fetch an OS auxilliary vector from the remote stub. This packet is a
3430 more efficient replacement for qPart:auxv:read.
3432 qXfer:memory-map:read:
3433 Fetch a memory map from the remote stub, including information about
3434 RAM, ROM, and flash memory devices.
3439 Erase and program a flash memory device.
3441 * Removed remote packets
3444 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3445 used it, and only gdbserver implemented it.
3447 *** Changes in GDB 6.5
3451 Renesas M32C/M16C m32c-elf
3453 Morpho Technologies ms1 ms1-elf
3457 init-if-undefined Initialize a convenience variable, but
3458 only if it doesn't already have a value.
3460 The following commands are presently only implemented for native GNU/Linux:
3462 checkpoint Save a snapshot of the program state.
3464 restart <n> Return the program state to a
3465 previously saved state.
3467 info checkpoints List currently saved checkpoints.
3469 delete-checkpoint <n> Delete a previously saved checkpoint.
3471 set|show detach-on-fork Tell gdb whether to detach from a newly
3472 forked process, or to keep debugging it.
3474 info forks List forks of the user program that
3475 are available to be debugged.
3477 fork <n> Switch to debugging one of several
3478 forks of the user program that are
3479 available to be debugged.
3481 delete-fork <n> Delete a fork from the list of forks
3482 that are available to be debugged (and
3483 kill the forked process).
3485 detach-fork <n> Delete a fork from the list of forks
3486 that are available to be debugged (and
3487 allow the process to continue).
3491 Morpho Technologies ms2 ms1-elf
3493 * Improved Windows host support
3495 GDB now builds as a cross debugger hosted on i686-mingw32, including
3496 native console support, and remote communications using either
3497 network sockets or serial ports.
3499 * Improved Modula-2 language support
3501 GDB can now print most types in the Modula-2 syntax. This includes:
3502 basic types, set types, record types, enumerated types, range types,
3503 pointer types and ARRAY types. Procedure var parameters are correctly
3504 printed and hexadecimal addresses and character constants are also
3505 written in the Modula-2 syntax. Best results can be obtained by using
3506 GNU Modula-2 together with the -gdwarf-2 command line option.
3510 The ARM rdi-share module.
3512 The Netware NLM debug server.
3514 *** Changes in GDB 6.4
3516 * New native configurations
3518 OpenBSD/arm arm*-*-openbsd*
3519 OpenBSD/mips64 mips64-*-openbsd*
3523 Morpho Technologies ms1 ms1-elf
3525 * New command line options
3527 --batch-silent As for --batch, but totally silent.
3528 --return-child-result The debugger will exist with the same value
3529 the child (debugged) program exited with.
3530 --eval-command COMMAND, -ex COMMAND
3531 Execute a single GDB CLI command. This may be
3532 specified multiple times and in conjunction
3533 with the --command (-x) option.
3535 * Deprecated commands removed
3537 The following commands, that were deprecated in 2000, have been
3541 set|show arm disassembly-flavor set|show arm disassembler
3542 othernames set arm disassembler
3543 set|show remotedebug set|show debug remote
3544 set|show archdebug set|show debug arch
3545 set|show eventdebug set|show debug event
3548 * New BSD user-level threads support
3550 It is now possible to debug programs using the user-level threads
3551 library on OpenBSD and FreeBSD. Currently supported (target)
3554 FreeBSD/amd64 x86_64-*-freebsd*
3555 FreeBSD/i386 i386-*-freebsd*
3556 OpenBSD/i386 i386-*-openbsd*
3558 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3559 are not yet supported.
3561 * New support for Matsushita MN10300 w/sim added
3562 (Work in progress). mn10300-elf.
3564 * REMOVED configurations and files
3566 VxWorks and the XDR protocol *-*-vxworks
3567 Motorola MCORE mcore-*-*
3568 National Semiconductor NS32000 ns32k-*-*
3570 * New "set print array-indexes" command
3572 After turning this setting "on", GDB prints the index of each element
3573 when displaying arrays. The default is "off" to preserve the previous
3576 * VAX floating point support
3578 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3580 * User-defined command support
3582 In addition to using $arg0..$arg9 for argument passing, it is now possible
3583 to use $argc to determine now many arguments have been passed. See the
3584 section on user-defined commands in the user manual for more information.
3586 *** Changes in GDB 6.3:
3588 * New command line option
3590 GDB now accepts -l followed by a number to set the timeout for remote
3593 * GDB works with GCC -feliminate-dwarf2-dups
3595 GDB now supports a more compact representation of DWARF-2 debug
3596 information using DW_FORM_ref_addr references. These are produced
3597 by GCC with the option -feliminate-dwarf2-dups and also by some
3598 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3599 to use -feliminate-dwarf2-dups.
3601 * Internationalization
3603 When supported by the host system, GDB will be built with
3604 internationalization (libintl). The task of marking up the sources is
3605 continued, we're looking forward to our first translation.
3609 Initial support for debugging programs compiled with the GNAT
3610 implementation of the Ada programming language has been integrated
3611 into GDB. In this release, support is limited to expression evaluation.
3613 * New native configurations
3615 GNU/Linux/m32r m32r-*-linux-gnu
3619 GDB's remote protocol now includes support for the 'p' packet. This
3620 packet is used to fetch individual registers from a remote inferior.
3622 * END-OF-LIFE registers[] compatibility module
3624 GDB's internal register infrastructure has been completely rewritten.
3625 The new infrastructure making possible the implementation of key new
3626 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3629 GDB 6.3 will be the last release to include the the registers[]
3630 compatibility module that allowed out-of-date configurations to
3631 continue to work. This change directly impacts the following
3641 powerpc bdm protocol
3643 Unless there is activity to revive these configurations, they will be
3644 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3646 * OBSOLETE configurations and files
3648 Configurations that have been declared obsolete in this release have
3649 been commented out. Unless there is activity to revive these
3650 configurations, the next release of GDB will have their sources
3651 permanently REMOVED.
3660 *** Changes in GDB 6.2.1:
3662 * MIPS `break main; run' gave an heuristic-fence-post warning
3664 When attempting to run even a simple program, a warning about
3665 heuristic-fence-post being hit would be reported. This problem has
3668 * MIPS IRIX 'long double' crashed GDB
3670 When examining a long double variable, GDB would get a segmentation
3671 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3672 IRIX long double values).
3676 A bug in the VAX stack code was causing problems with the "next"
3677 command. This problem has been fixed.
3679 *** Changes in GDB 6.2:
3681 * Fix for ``many threads''
3683 On GNU/Linux systems that use the NPTL threads library, a program
3684 rapidly creating and deleting threads would confuse GDB leading to the
3687 ptrace: No such process.
3688 thread_db_get_info: cannot get thread info: generic error
3690 This problem has been fixed.
3692 * "-async" and "-noasync" options removed.
3694 Support for the broken "-noasync" option has been removed (it caused
3697 * New ``start'' command.
3699 This command runs the program until the begining of the main procedure.
3701 * New BSD Kernel Data Access Library (libkvm) interface
3703 Using ``target kvm'' it is now possible to debug kernel core dumps and
3704 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3705 platforms. Currently supported (native-only) configurations are:
3707 FreeBSD/amd64 x86_64-*-freebsd*
3708 FreeBSD/i386 i?86-*-freebsd*
3709 NetBSD/i386 i?86-*-netbsd*
3710 NetBSD/m68k m68*-*-netbsd*
3711 NetBSD/sparc sparc-*-netbsd*
3712 OpenBSD/amd64 x86_64-*-openbsd*
3713 OpenBSD/i386 i?86-*-openbsd*
3714 OpenBSD/m68k m68*-openbsd*
3715 OpenBSD/sparc sparc-*-openbsd*
3717 * Signal trampoline code overhauled
3719 Many generic problems with GDB's signal handling code have been fixed.
3720 These include: backtraces through non-contiguous stacks; recognition
3721 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3722 call; backtrace through a signal trampoline; step into and out of
3723 signal handlers; and single-stepping in the signal trampoline.
3725 Please note that kernel bugs are a limiting factor here. These
3726 features have been shown to work on an s390 GNU/Linux system that
3727 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3729 * Cygwin support for DWARF 2 added.
3731 * New native configurations
3733 GNU/Linux/hppa hppa*-*-linux*
3734 OpenBSD/hppa hppa*-*-openbsd*
3735 OpenBSD/m68k m68*-*-openbsd*
3736 OpenBSD/m88k m88*-*-openbsd*
3737 OpenBSD/powerpc powerpc-*-openbsd*
3738 NetBSD/vax vax-*-netbsd*
3739 OpenBSD/vax vax-*-openbsd*
3741 * END-OF-LIFE frame compatibility module
3743 GDB's internal frame infrastructure has been completely rewritten.
3744 The new infrastructure making it possible to support key new features
3745 including DWARF 2 Call Frame Information. To aid in the task of
3746 migrating old configurations to this new infrastructure, a
3747 compatibility module, that allowed old configurations to continue to
3748 work, was also included.
3750 GDB 6.2 will be the last release to include this frame compatibility
3751 module. This change directly impacts the following configurations:
3761 Unless there is activity to revive these configurations, they will be
3762 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3764 * REMOVED configurations and files
3766 Sun 3, running SunOS 3 m68*-*-sunos3*
3767 Sun 3, running SunOS 4 m68*-*-sunos4*
3768 Sun 2, running SunOS 3 m68000-*-sunos3*
3769 Sun 2, running SunOS 4 m68000-*-sunos4*
3770 Motorola 680x0 running LynxOS m68*-*-lynxos*
3771 AT&T 3b1/Unix pc m68*-att-*
3772 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3773 decstation mips-dec-* mips-little-*
3774 riscos mips-*-riscos* mips-*-sysv*
3775 sonymips mips-sony-*
3776 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3778 *** Changes in GDB 6.1.1:
3780 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3782 The TUI (Text-mode User Interface) is now built as part of a default
3783 GDB configuration. It is enabled by either selecting the TUI with the
3784 command line option "-i=tui" or by running the separate "gdbtui"
3785 program. For more information on the TUI, see the manual "Debugging
3788 * Pending breakpoint support (also included in GDB 6.1)
3790 Support has been added to allow you to specify breakpoints in shared
3791 libraries that have not yet been loaded. If a breakpoint location
3792 cannot be found, and the "breakpoint pending" option is set to auto,
3793 GDB queries you if you wish to make the breakpoint pending on a future
3794 shared-library load. If and when GDB resolves the breakpoint symbol,
3795 the pending breakpoint is removed as one or more regular breakpoints
3798 Pending breakpoints are very useful for GCJ Java debugging.
3800 * Fixed ISO-C build problems
3802 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3803 non ISO-C code that stopped them being built using a more strict ISO-C
3804 compiler (e.g., IBM's C compiler).
3806 * Fixed build problem on IRIX 5
3808 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3809 wasn't able to compile compile on an IRIX 5 system.
3811 * Added execute permission to gdb/gdbserver/configure
3813 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3814 permission. This bug would cause configure to fail on a number of
3815 systems (Solaris, IRIX). Ref: server/519.
3817 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3819 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3820 has been updated to use constant array sizes.
3822 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3824 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3825 its generated DWARF Call Frame Info. This encoding was causing GDB to
3826 panic, that panic has been fixed. Ref: gdb/1628.
3828 * Fixed a problem when examining parameters in shared library code.
3830 When examining parameters in optimized shared library code generated
3831 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3832 not available''. GDB now correctly displays the variable's value.
3834 *** Changes in GDB 6.1:
3836 * Removed --with-mmalloc
3838 Support for the mmalloc memory manager has been removed, as it
3839 conflicted with the internal gdb byte cache.
3841 * Changes in AMD64 configurations
3843 The AMD64 target now includes the %cs and %ss registers. As a result
3844 the AMD64 remote protocol has changed; this affects the floating-point
3845 and SSE registers. If you rely on those registers for your debugging,
3846 you should upgrade gdbserver on the remote side.
3848 * Revised SPARC target
3850 The SPARC target has been completely revised, incorporating the
3851 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3852 support for LynxOS and SunOS 4 has been dropped. Calling functions
3853 from within GDB on operating systems with a non-executable stack
3854 (Solaris, OpenBSD) now works.
3858 GDB has a new C++ demangler which does a better job on the mangled
3859 names generated by current versions of g++. It also runs faster, so
3860 with this and other changes gdb should now start faster on large C++
3863 * DWARF 2 Location Expressions
3865 GDB support for location expressions has been extended to support function
3866 arguments and frame bases. Older versions of GDB could crash when they
3869 * C++ nested types and namespaces
3871 GDB's support for nested types and namespaces in C++ has been
3872 improved, especially if you use the DWARF 2 debugging format. (This
3873 is the default for recent versions of GCC on most platforms.)
3874 Specifically, if you have a class "Inner" defined within a class or
3875 namespace "Outer", then GDB realizes that the class's name is
3876 "Outer::Inner", not simply "Inner". This should greatly reduce the
3877 frequency of complaints about not finding RTTI symbols. In addition,
3878 if you are stopped at inside of a function defined within a namespace,
3879 GDB modifies its name lookup accordingly.
3881 * New native configurations
3883 NetBSD/amd64 x86_64-*-netbsd*
3884 OpenBSD/amd64 x86_64-*-openbsd*
3885 OpenBSD/alpha alpha*-*-openbsd*
3886 OpenBSD/sparc sparc-*-openbsd*
3887 OpenBSD/sparc64 sparc64-*-openbsd*
3889 * New debugging protocols
3891 M32R with SDI protocol m32r-*-elf*
3893 * "set prompt-escape-char" command deleted.
3895 The command "set prompt-escape-char" has been deleted. This command,
3896 and its very obscure effet on GDB's prompt, was never documented,
3897 tested, nor mentioned in the NEWS file.
3899 * OBSOLETE configurations and files
3901 Configurations that have been declared obsolete in this release have
3902 been commented out. Unless there is activity to revive these
3903 configurations, the next release of GDB will have their sources
3904 permanently REMOVED.
3906 Sun 3, running SunOS 3 m68*-*-sunos3*
3907 Sun 3, running SunOS 4 m68*-*-sunos4*
3908 Sun 2, running SunOS 3 m68000-*-sunos3*
3909 Sun 2, running SunOS 4 m68000-*-sunos4*
3910 Motorola 680x0 running LynxOS m68*-*-lynxos*
3911 AT&T 3b1/Unix pc m68*-att-*
3912 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3913 decstation mips-dec-* mips-little-*
3914 riscos mips-*-riscos* mips-*-sysv*
3915 sonymips mips-sony-*
3916 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3918 * REMOVED configurations and files
3920 SGI Irix-4.x mips-sgi-irix4 or iris4
3921 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3922 Z8000 simulator z8k-zilog-none or z8ksim
3923 Matsushita MN10200 w/simulator mn10200-*-*
3924 H8/500 simulator h8500-hitachi-hms or h8500hms
3925 HP/PA running BSD hppa*-*-bsd*
3926 HP/PA running OSF/1 hppa*-*-osf*
3927 HP/PA Pro target hppa*-*-pro*
3928 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3929 386BSD i[3456]86-*-bsd*
3930 Sequent family i[3456]86-sequent-sysv4*
3931 i[3456]86-sequent-sysv*
3932 i[3456]86-sequent-bsd*
3933 SPARC running LynxOS sparc-*-lynxos*
3934 SPARC running SunOS 4 sparc-*-sunos4*
3935 Tsqware Sparclet sparclet-*-*
3936 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3938 *** Changes in GDB 6.0:
3942 Support for debugging the Objective-C programming language has been
3943 integrated into GDB.
3945 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3947 DWARF 2's Call Frame Information makes available compiler generated
3948 information that more exactly describes the program's run-time stack.
3949 By using this information, GDB is able to provide more robust stack
3952 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3953 have been updated to use a new backtrace mechanism which includes
3954 DWARF 2 CFI support.
3958 GDB's remote protocol has been extended to include support for hosted
3959 file I/O (where the remote target uses GDB's file system). See GDB's
3960 remote protocol documentation for details.
3962 * All targets using the new architecture framework.
3964 All of GDB's targets have been updated to use the new internal
3965 architecture framework. The way is now open for future GDB releases
3966 to include cross-architecture native debugging support (i386 on amd64,
3969 * GNU/Linux's Thread Local Storage (TLS)
3971 GDB now includes support for for the GNU/Linux implementation of
3972 per-thread variables.
3974 * GNU/Linux's Native POSIX Thread Library (NPTL)
3976 GDB's thread code has been updated to work with either the new
3977 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3979 * Separate debug info.
3981 GDB, in conjunction with BINUTILS, now supports a mechanism for
3982 automatically loading debug information from a separate file. Instead
3983 of shipping full debug and non-debug versions of system libraries,
3984 system integrators can now instead ship just the stripped libraries
3985 and optional debug files.
3987 * DWARF 2 Location Expressions
3989 DWARF 2 Location Expressions allow the compiler to more completely
3990 describe the location of variables (even in optimized code) to the
3993 GDB now includes preliminary support for location expressions (support
3994 for DW_OP_piece is still missing).
3998 A number of long standing bugs that caused GDB to die while starting a
3999 Java application have been fixed. GDB's Java support is now
4000 considered "useable".
4002 * GNU/Linux support for fork, vfork, and exec.
4004 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4005 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4008 * GDB supports logging output to a file
4010 There are two new commands, "set logging" and "show logging", which can be
4011 used to capture GDB's output to a file.
4013 * The meaning of "detach" has changed for gdbserver
4015 The "detach" command will now resume the application, as documented. To
4016 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4019 * d10v, m68hc11 `regs' command deprecated
4021 The `info registers' command has been updated so that it displays the
4022 registers using a format identical to the old `regs' command.
4026 A new command, "maint set profile on/off", has been added. This command can
4027 be used to enable or disable profiling while running GDB, to profile a
4028 session or a set of commands. In addition there is a new configure switch,
4029 "--enable-profiling", which will cause GDB to be compiled with profiling
4030 data, for more informative profiling results.
4032 * Default MI syntax changed to "mi2".
4034 The default MI (machine interface) syntax, enabled by the command line
4035 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4036 "mi1", can be enabled by specifying the option "-i=mi1".
4038 Support for the original "mi0" syntax (included in GDB 5.0) has been
4041 Fix for gdb/192: removed extraneous space when displaying frame level.
4042 Fix for gdb/672: update changelist is now output in mi list format.
4043 Fix for gdb/702: a -var-assign that updates the value now shows up
4044 in a subsequent -var-update.
4046 * New native configurations.
4048 FreeBSD/amd64 x86_64-*-freebsd*
4050 * Multi-arched targets.
4052 HP/PA HPUX11 hppa*-*-hpux*
4053 Renesas M32R/D w/simulator m32r-*-elf*
4055 * OBSOLETE configurations and files
4057 Configurations that have been declared obsolete in this release have
4058 been commented out. Unless there is activity to revive these
4059 configurations, the next release of GDB will have their sources
4060 permanently REMOVED.
4062 Z8000 simulator z8k-zilog-none or z8ksim
4063 Matsushita MN10200 w/simulator mn10200-*-*
4064 H8/500 simulator h8500-hitachi-hms or h8500hms
4065 HP/PA running BSD hppa*-*-bsd*
4066 HP/PA running OSF/1 hppa*-*-osf*
4067 HP/PA Pro target hppa*-*-pro*
4068 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4069 Sequent family i[3456]86-sequent-sysv4*
4070 i[3456]86-sequent-sysv*
4071 i[3456]86-sequent-bsd*
4072 Tsqware Sparclet sparclet-*-*
4073 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4075 * REMOVED configurations and files
4078 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4079 IBM AIX PS/2 i[3456]86-*-aix
4080 i386 running Mach 3.0 i[3456]86-*-mach3*
4081 i386 running Mach i[3456]86-*-mach*
4082 i386 running OSF/1 i[3456]86-*osf1mk*
4083 HP/Apollo 68k Family m68*-apollo*-sysv*,
4085 m68*-hp-bsd*, m68*-hp-hpux*
4086 Argonaut Risc Chip (ARC) arc-*-*
4087 Mitsubishi D30V d30v-*-*
4088 Fujitsu FR30 fr30-*-elf*
4089 OS/9000 i[34]86-*-os9k
4090 I960 with MON960 i960-*-coff
4092 * MIPS $fp behavior changed
4094 The convenience variable $fp, for the MIPS, now consistently returns
4095 the address of the current frame's base. Previously, depending on the
4096 context, $fp could refer to either $sp or the current frame's base
4097 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4098 The GNU Source-Level Debugger''.
4100 *** Changes in GDB 5.3:
4102 * GNU/Linux shared library multi-threaded performance improved.
4104 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4105 `/proc', in preference to `ptrace' for memory reads. This may result
4106 in an improvement in the start-up time of multi-threaded, shared
4107 library applications when run under GDB. One GDB user writes: ``loads
4108 shared libs like mad''.
4110 * ``gdbserver'' now supports multi-threaded applications on some targets
4112 Support for debugging multi-threaded applications which use
4113 the GNU/Linux LinuxThreads package has been added for
4114 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4115 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4117 * GDB now supports C/C++ preprocessor macros.
4119 GDB now expands preprocessor macro invocations in C/C++ expressions,
4120 and provides various commands for showing macro definitions and how
4123 The new command `macro expand EXPRESSION' expands any macro
4124 invocations in expression, and shows the result.
4126 The new command `show macro MACRO-NAME' shows the definition of the
4127 macro named MACRO-NAME, and where it was defined.
4129 Most compilers don't include information about macros in the debugging
4130 information by default. In GCC 3.1, for example, you need to compile
4131 your program with the options `-gdwarf-2 -g3'. If the macro
4132 information is present in the executable, GDB will read it.
4134 * Multi-arched targets.
4136 DEC Alpha (partial) alpha*-*-*
4137 DEC VAX (partial) vax-*-*
4139 National Semiconductor NS32000 (partial) ns32k-*-*
4140 Motorola 68000 (partial) m68k-*-*
4141 Motorola MCORE mcore-*-*
4145 Fujitsu FRV architecture added by Red Hat frv*-*-*
4148 * New native configurations
4150 Alpha NetBSD alpha*-*-netbsd*
4151 SH NetBSD sh*-*-netbsdelf*
4152 MIPS NetBSD mips*-*-netbsd*
4153 UltraSPARC NetBSD sparc64-*-netbsd*
4155 * OBSOLETE configurations and files
4157 Configurations that have been declared obsolete in this release have
4158 been commented out. Unless there is activity to revive these
4159 configurations, the next release of GDB will have their sources
4160 permanently REMOVED.
4162 Mitsubishi D30V d30v-*-*
4163 OS/9000 i[34]86-*-os9k
4164 IBM AIX PS/2 i[3456]86-*-aix
4165 Fujitsu FR30 fr30-*-elf*
4166 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4167 Argonaut Risc Chip (ARC) arc-*-*
4168 i386 running Mach 3.0 i[3456]86-*-mach3*
4169 i386 running Mach i[3456]86-*-mach*
4170 i386 running OSF/1 i[3456]86-*osf1mk*
4171 HP/Apollo 68k Family m68*-apollo*-sysv*,
4173 m68*-hp-bsd*, m68*-hp-hpux*
4174 I960 with MON960 i960-*-coff
4176 * OBSOLETE languages
4178 CHILL, a Pascal like language used by telecommunications companies.
4180 * REMOVED configurations and files
4182 AMD 29k family via UDI a29k-amd-udi, udi29k
4183 A29K VxWorks a29k-*-vxworks
4184 AMD 29000 embedded, using EBMON a29k-none-none
4185 AMD 29000 embedded with COFF a29k-none-coff
4186 AMD 29000 embedded with a.out a29k-none-aout
4188 testsuite/gdb.hp/gdb.threads-hp/ directory
4190 * New command "set max-user-call-depth <nnn>"
4192 This command allows the user to limit the call depth of user-defined
4193 commands. The default is 1024.
4195 * Changes in FreeBSD/i386 native debugging.
4197 Support for the "generate-core-file" has been added.
4199 * New commands "dump", "append", and "restore".
4201 These commands allow data to be copied from target memory
4202 to a bfd-format or binary file (dump and append), and back
4203 from a file into memory (restore).
4205 * Improved "next/step" support on multi-processor Alpha Tru64.
4207 The previous single-step mechanism could cause unpredictable problems,
4208 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4209 of a software single-step mechanism prevents this.
4211 *** Changes in GDB 5.2.1:
4219 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4220 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4221 Fix, by Joel Brobecker imported from mainline.
4223 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4224 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4225 Fix, by Fred Fish, imported from mainline.
4227 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4228 Surprisingly enough, it works now.
4229 By Michal Ludvig, imported from mainline.
4231 i386 hardware watchpoint support:
4232 avoid misses on second run for some targets.
4233 By Pierre Muller, imported from mainline.
4235 *** Changes in GDB 5.2:
4237 * New command "set trust-readonly-sections on[off]".
4239 This command is a hint that tells gdb that read-only sections
4240 really are read-only (ie. that their contents will not change).
4241 In this mode, gdb will go to the object file rather than the
4242 target to read memory from read-only sections (such as ".text").
4243 This can be a significant performance improvement on some
4244 (notably embedded) targets.
4246 * New command "generate-core-file" (or "gcore").
4248 This new gdb command allows the user to drop a core file of the child
4249 process state at any time. So far it's been implemented only for
4250 GNU/Linux and Solaris, but should be relatively easily ported to other
4251 hosts. Argument is core file name (defaults to core.<pid>).
4253 * New command line option
4255 GDB now accepts --pid or -p followed by a process id.
4257 * Change in command line behavior -- corefiles vs. process ids.
4259 There is a subtle behavior in the way in which GDB handles
4260 command line arguments. The first non-flag argument is always
4261 a program to debug, but the second non-flag argument may either
4262 be a corefile or a process id. Previously, GDB would attempt to
4263 open the second argument as a corefile, and if that failed, would
4264 issue a superfluous error message and then attempt to attach it as
4265 a process. Now, if the second argument begins with a non-digit,
4266 it will be treated as a corefile. If it begins with a digit,
4267 GDB will attempt to attach it as a process, and if no such process
4268 is found, will then attempt to open it as a corefile.
4270 * Changes in ARM configurations.
4272 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4273 configuration is fully multi-arch.
4275 * New native configurations
4277 ARM NetBSD arm*-*-netbsd*
4278 x86 OpenBSD i[3456]86-*-openbsd*
4279 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4280 Sparc64 running FreeBSD sparc64-*-freebsd*
4284 Sanyo XStormy16 xstormy16-elf
4286 * OBSOLETE configurations and files
4288 Configurations that have been declared obsolete in this release have
4289 been commented out. Unless there is activity to revive these
4290 configurations, the next release of GDB will have their sources
4291 permanently REMOVED.
4293 AMD 29k family via UDI a29k-amd-udi, udi29k
4294 A29K VxWorks a29k-*-vxworks
4295 AMD 29000 embedded, using EBMON a29k-none-none
4296 AMD 29000 embedded with COFF a29k-none-coff
4297 AMD 29000 embedded with a.out a29k-none-aout
4299 testsuite/gdb.hp/gdb.threads-hp/ directory
4301 * REMOVED configurations and files
4303 TI TMS320C80 tic80-*-*
4305 PowerPC Solaris powerpcle-*-solaris*
4306 PowerPC Windows NT powerpcle-*-cygwin32
4307 PowerPC Netware powerpc-*-netware*
4308 Harris/CXUX m88k m88*-harris-cxux*
4309 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4310 ns32k-utek-sysv* ns32k-utek-*
4311 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4312 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4313 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4314 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4315 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4317 * Changes to command line processing
4319 The new `--args' feature can be used to specify command-line arguments
4320 for the inferior from gdb's command line.
4322 * Changes to key bindings
4324 There is a new `operate-and-get-next' function bound to `C-o'.
4326 *** Changes in GDB 5.1.1
4328 Fix compile problem on DJGPP.
4330 Fix a problem with floating-point registers on the i386 being
4333 Fix to stop GDB crashing on .debug_str debug info.
4335 Numerous documentation fixes.
4337 Numerous testsuite fixes.
4339 *** Changes in GDB 5.1:
4341 * New native configurations
4343 Alpha FreeBSD alpha*-*-freebsd*
4344 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4345 MIPS GNU/Linux mips*-*-linux*
4346 MIPS SGI Irix 6.x mips*-sgi-irix6*
4347 ia64 AIX ia64-*-aix*
4348 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4352 Motorola 68HC11 and 68HC12 m68hc11-elf
4354 UltraSparc running GNU/Linux sparc64-*-linux*
4356 * OBSOLETE configurations and files
4358 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4359 Harris/CXUX m88k m88*-harris-cxux*
4360 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4361 ns32k-utek-sysv* ns32k-utek-*
4362 TI TMS320C80 tic80-*-*
4364 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4365 PowerPC Solaris powerpcle-*-solaris*
4366 PowerPC Windows NT powerpcle-*-cygwin32
4367 PowerPC Netware powerpc-*-netware*
4368 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4369 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4370 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4371 Apple Macintosh (MPW) host N/A
4373 stuff.c (Program to stuff files into a specially prepared space in kdb)
4374 kdb-start.c (Main loop for the standalone kernel debugger)
4376 Configurations that have been declared obsolete in this release have
4377 been commented out. Unless there is activity to revive these
4378 configurations, the next release of GDB will have their sources
4379 permanently REMOVED.
4381 * REMOVED configurations and files
4383 Altos 3068 m68*-altos-*
4384 Convex c1-*-*, c2-*-*
4386 ARM RISCix arm-*-* (as host)
4390 * GDB has been converted to ISO C.
4392 GDB's source code has been converted to ISO C. In particular, the
4393 sources are fully protoized, and rely on standard headers being
4398 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4400 * The MI enabled by default.
4402 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4403 revised and enabled by default. Packages which use GDB as a debugging
4404 engine behind a UI or another front end are encouraged to switch to
4405 using the GDB/MI interface, instead of the old annotations interface
4406 which is now deprecated.
4408 * Support for debugging Pascal programs.
4410 GDB now includes support for debugging Pascal programs. The following
4411 main features are supported:
4413 - Pascal-specific data types such as sets;
4415 - automatic recognition of Pascal sources based on file-name
4418 - Pascal-style display of data types, variables, and functions;
4420 - a Pascal expression parser.
4422 However, some important features are not yet supported.
4424 - Pascal string operations are not supported at all;
4426 - there are some problems with boolean types;
4428 - Pascal type hexadecimal constants are not supported
4429 because they conflict with the internal variables format;
4431 - support for Pascal objects and classes is not full yet;
4433 - unlike Pascal, GDB is case-sensitive for symbol names.
4435 * Changes in completion.
4437 Commands such as `shell', `run' and `set args', which pass arguments
4438 to inferior programs, now complete on file names, similar to what
4439 users expect at the shell prompt.
4441 Commands which accept locations, such as `disassemble', `print',
4442 `breakpoint', `until', etc. now complete on filenames as well as
4443 program symbols. Thus, if you type "break foob TAB", and the source
4444 files linked into the programs include `foobar.c', that file name will
4445 be one of the candidates for completion. However, file names are not
4446 considered for completion after you typed a colon that delimits a file
4447 name from a name of a function in that file, as in "break foo.c:bar".
4449 `set demangle-style' completes on available demangling styles.
4451 * New platform-independent commands:
4453 It is now possible to define a post-hook for a command as well as a
4454 hook that runs before the command. For more details, see the
4455 documentation of `hookpost' in the GDB manual.
4457 * Changes in GNU/Linux native debugging.
4459 Support for debugging multi-threaded programs has been completely
4460 revised for all platforms except m68k and sparc. You can now debug as
4461 many threads as your system allows you to have.
4463 Attach/detach is supported for multi-threaded programs.
4465 Support for SSE registers was added for x86. This doesn't work for
4466 multi-threaded programs though.
4468 * Changes in MIPS configurations.
4470 Multi-arch support is enabled for all MIPS configurations.
4472 GDB can now be built as native debugger on SGI Irix 6.x systems for
4473 debugging n32 executables. (Debugging 64-bit executables is not yet
4476 * Unified support for hardware watchpoints in all x86 configurations.
4478 Most (if not all) native x86 configurations support hardware-assisted
4479 breakpoints and watchpoints in a unified manner. This support
4480 implements debug register sharing between watchpoints, which allows to
4481 put a virtually infinite number of watchpoints on the same address,
4482 and also supports watching regions up to 16 bytes with several debug
4485 The new maintenance command `maintenance show-debug-regs' toggles
4486 debugging print-outs in functions that insert, remove, and test
4487 watchpoints and hardware breakpoints.
4489 * Changes in the DJGPP native configuration.
4491 New command ``info dos sysinfo'' displays assorted information about
4492 the CPU, OS, memory, and DPMI server.
4494 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4495 display information about segment descriptors stored in GDT, LDT, and
4498 New commands ``info dos pde'' and ``info dos pte'' display entries
4499 from Page Directory and Page Tables (for now works with CWSDPMI only).
4500 New command ``info dos address-pte'' displays the Page Table entry for
4501 a given linear address.
4503 GDB can now pass command lines longer than 126 characters to the
4504 program being debugged (requires an update to the libdbg.a library
4505 which is part of the DJGPP development kit).
4507 DWARF2 debug info is now supported.
4509 It is now possible to `step' and `next' through calls to `longjmp'.
4511 * Changes in documentation.
4513 All GDB documentation was converted to GFDL, the GNU Free
4514 Documentation License.
4516 Tracepoints-related commands are now fully documented in the GDB
4519 TUI, the Text-mode User Interface, is now documented in the manual.
4521 Tracepoints-related commands are now fully documented in the GDB
4524 The "GDB Internals" manual now has an index. It also includes
4525 documentation of `ui_out' functions, GDB coding standards, x86
4526 hardware watchpoints, and memory region attributes.
4528 * GDB's version number moved to ``version.in''
4530 The Makefile variable VERSION has been replaced by the file
4531 ``version.in''. People creating GDB distributions should update the
4532 contents of this file.
4536 GUD support is now a standard part of the EMACS distribution.
4538 *** Changes in GDB 5.0:
4540 * Improved support for debugging FP programs on x86 targets
4542 Unified and much-improved support for debugging floating-point
4543 programs on all x86 targets. In particular, ``info float'' now
4544 displays the FP registers in the same format on all x86 targets, with
4545 greater level of detail.
4547 * Improvements and bugfixes in hardware-assisted watchpoints
4549 It is now possible to watch array elements, struct members, and
4550 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4551 on x86 targets no longer erroneously trigger when the address is
4554 * Improvements in the native DJGPP version of GDB
4556 The distribution now includes all the scripts and auxiliary files
4557 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4558 machines ``out of the box''.
4560 The DJGPP version can now debug programs that use signals. It is
4561 possible to catch signals that happened in the debuggee, deliver
4562 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4563 would kill the program being debugged.) Programs that hook hardware
4564 interrupts (keyboard, timer, etc.) can also be debugged.
4566 It is now possible to debug DJGPP programs that redirect their
4567 standard handles or switch them to raw (as opposed to cooked) mode, or
4568 even close them. The command ``run < foo > bar'' works as expected,
4569 and ``info terminal'' reports useful information about the debuggee's
4570 terminal, including raw/cooked mode, redirection, etc.
4572 The DJGPP version now uses termios functions for console I/O, which
4573 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4576 DOS-style file names with drive letters are now fully supported by
4579 It is now possible to debug DJGPP programs that switch their working
4580 directory. It is also possible to rerun the debuggee any number of
4581 times without restarting GDB; thus, you can use the same setup,
4582 breakpoints, etc. for many debugging sessions.
4584 * New native configurations
4586 ARM GNU/Linux arm*-*-linux*
4587 PowerPC GNU/Linux powerpc-*-linux*
4591 Motorola MCore mcore-*-*
4592 x86 VxWorks i[3456]86-*-vxworks*
4593 PowerPC VxWorks powerpc-*-vxworks*
4594 TI TMS320C80 tic80-*-*
4596 * OBSOLETE configurations
4598 Altos 3068 m68*-altos-*
4599 Convex c1-*-*, c2-*-*
4601 ARM RISCix arm-*-* (as host)
4604 Configurations that have been declared obsolete will be commented out,
4605 but the code will be left in place. If there is no activity to revive
4606 these configurations before the next release of GDB, the sources will
4607 be permanently REMOVED.
4609 * Gould support removed
4611 Support for the Gould PowerNode and NP1 has been removed.
4613 * New features for SVR4
4615 On SVR4 native platforms (such as Solaris), if you attach to a process
4616 without first loading a symbol file, GDB will now attempt to locate and
4617 load symbols from the running process's executable file.
4619 * Many C++ enhancements
4621 C++ support has been greatly improved. Overload resolution now works properly
4622 in almost all cases. RTTI support is on the way.
4624 * Remote targets can connect to a sub-program
4626 A popen(3) style serial-device has been added. This device starts a
4627 sub-process (such as a stand-alone simulator) and then communicates
4628 with that. The sub-program to run is specified using the syntax
4629 ``|<program> <args>'' vis:
4631 (gdb) set remotedebug 1
4632 (gdb) target extended-remote |mn10300-elf-sim program-args
4634 * MIPS 64 remote protocol
4636 A long standing bug in the mips64 remote protocol where by GDB
4637 expected certain 32 bit registers (ex SR) to be transfered as 32
4638 instead of 64 bits has been fixed.
4640 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4641 added to provide backward compatibility with older versions of GDB.
4643 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4645 The command ``set remotebinarydownload'' command has been replaced by
4646 ``set remote X-packet''. Other commands in ``set remote'' family
4647 include ``set remote P-packet''.
4649 * Breakpoint commands accept ranges.
4651 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4652 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4653 ``tracepoint passcount'' also accepts a range of tracepoints.
4655 * ``apropos'' command added.
4657 The ``apropos'' command searches through command names and
4658 documentation strings, printing out matches, making it much easier to
4659 try to find a command that does what you are looking for.
4663 A new machine oriented interface (MI) has been added to GDB. This
4664 interface is designed for debug environments running GDB as a separate
4665 process. This is part of the long term libGDB project. See the
4666 "GDB/MI" chapter of the GDB manual for further information. It can be
4667 enabled by configuring with:
4669 .../configure --enable-gdbmi
4671 *** Changes in GDB-4.18:
4673 * New native configurations
4675 HP-UX 10.20 hppa*-*-hpux10.20
4676 HP-UX 11.x hppa*-*-hpux11.0*
4677 M68K GNU/Linux m68*-*-linux*
4681 Fujitsu FR30 fr30-*-elf*
4682 Intel StrongARM strongarm-*-*
4683 Mitsubishi D30V d30v-*-*
4685 * OBSOLETE configurations
4687 Gould PowerNode, NP1 np1-*-*, pn-*-*
4689 Configurations that have been declared obsolete will be commented out,
4690 but the code will be left in place. If there is no activity to revive
4691 these configurations before the next release of GDB, the sources will
4692 be permanently REMOVED.
4696 As a compatibility experiment, GDB's source files buildsym.h and
4697 buildsym.c have been converted to pure standard C, no longer
4698 containing any K&R compatibility code. We believe that all systems in
4699 use today either come with a standard C compiler, or have a GCC port
4700 available. If this is not true, please report the affected
4701 configuration to bug-gdb@gnu.org immediately. See the README file for
4702 information about getting a standard C compiler if you don't have one
4707 GDB now uses readline 2.2.
4709 * set extension-language
4711 You can now control the mapping between filename extensions and source
4712 languages by using the `set extension-language' command. For instance,
4713 you can ask GDB to treat .c files as C++ by saying
4714 set extension-language .c c++
4715 The command `info extensions' lists all of the recognized extensions
4716 and their associated languages.
4718 * Setting processor type for PowerPC and RS/6000
4720 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4721 you can use the `set processor' command to specify what variant of the
4722 PowerPC family you are debugging. The command
4726 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4727 following PowerPC and RS6000 variants:
4729 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4730 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4732 403GC IBM PowerPC 403GC
4733 505 Motorola PowerPC 505
4734 860 Motorola PowerPC 860 or 850
4735 601 Motorola PowerPC 601
4736 602 Motorola PowerPC 602
4737 603 Motorola/IBM PowerPC 603 or 603e
4738 604 Motorola PowerPC 604 or 604e
4739 750 Motorola/IBM PowerPC 750 or 750
4741 At the moment, this command just tells GDB what to name the
4742 special-purpose processor registers. Since almost all the affected
4743 registers are inaccessible to user-level programs, this command is
4744 only useful for remote debugging in its present form.
4748 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4749 more extensive support for HP-UX. Added features include shared
4750 library support, kernel threads and hardware watchpoints for 11.00,
4751 support for HP's ANSI C and C++ compilers, and a compatibility mode
4752 for xdb and dbx commands.
4756 HP's donation includes the new concept of catchpoints, which is a
4757 generalization of the old catch command. On HP-UX, it is now possible
4758 to catch exec, fork, and vfork, as well as library loading.
4760 This means that the existing catch command has changed; its first
4761 argument now specifies the type of catch to be set up. See the
4762 output of "help catch" for a list of catchpoint types.
4764 * Debugging across forks
4766 On HP-UX, you can choose which process to debug when a fork() happens
4771 HP has donated a curses-based terminal user interface (TUI). To get
4772 it, build with --enable-tui. Although this can be enabled for any
4773 configuration, at present it only works for native HP debugging.
4775 * GDB remote protocol additions
4777 A new protocol packet 'X' that writes binary data is now available.
4778 Default behavior is to try 'X', then drop back to 'M' if the stub
4779 fails to respond. The settable variable `remotebinarydownload'
4780 allows explicit control over the use of 'X'.
4782 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4783 full 64-bit address. The command
4785 set remoteaddresssize 32
4787 can be used to revert to the old behaviour. For existing remote stubs
4788 the change should not be noticed, as the additional address information
4791 In order to assist in debugging stubs, you may use the maintenance
4792 command `packet' to send any text string to the stub. For instance,
4794 maint packet heythere
4796 sends the packet "$heythere#<checksum>". Note that it is very easy to
4797 disrupt a debugging session by sending the wrong packet at the wrong
4800 The compare-sections command allows you to compare section data on the
4801 target to what is in the executable file without uploading or
4802 downloading, by comparing CRC checksums.
4804 * Tracing can collect general expressions
4806 You may now collect general expressions at tracepoints. This requires
4807 further additions to the target-side stub; see tracepoint.c and
4808 doc/agentexpr.texi for further details.
4810 * mask-address variable for Mips
4812 For Mips targets, you may control the zeroing of the upper 32 bits of
4813 a 64-bit address by entering `set mask-address on'. This is mainly
4814 of interest to users of embedded R4xxx and R5xxx processors.
4816 * Higher serial baud rates
4818 GDB's serial code now allows you to specify baud rates 57600, 115200,
4819 230400, and 460800 baud. (Note that your host system may not be able
4820 to achieve all of these rates.)
4824 The i960 configuration now includes an initial implementation of a
4825 builtin simulator, contributed by Jim Wilson.
4828 *** Changes in GDB-4.17:
4830 * New native configurations
4832 Alpha GNU/Linux alpha*-*-linux*
4833 Unixware 2.x i[3456]86-unixware2*
4834 Irix 6.x mips*-sgi-irix6*
4835 PowerPC GNU/Linux powerpc-*-linux*
4836 PowerPC Solaris powerpcle-*-solaris*
4837 Sparc GNU/Linux sparc-*-linux*
4838 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4842 Argonaut Risc Chip (ARC) arc-*-*
4843 Hitachi H8/300S h8300*-*-*
4844 Matsushita MN10200 w/simulator mn10200-*-*
4845 Matsushita MN10300 w/simulator mn10300-*-*
4846 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4847 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4848 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4849 Mitsubishi D10V w/simulator d10v-*-*
4850 Mitsubishi M32R/D w/simulator m32r-*-elf*
4851 Tsqware Sparclet sparclet-*-*
4852 NEC V850 w/simulator v850-*-*
4854 * New debugging protocols
4856 ARM with RDI protocol arm*-*-*
4857 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4858 DDB and LSI variants of PMON protocol mips*-*-*
4859 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4860 PowerPC with SDS protocol powerpc{,le}-*-eabi
4861 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4865 All configurations can now understand and use the DWARF 2 debugging
4866 format. The choice is automatic, if the symbol file contains DWARF 2
4871 GDB now includes basic Java language support. This support is
4872 only useful with Java compilers that produce native machine code.
4874 * solib-absolute-prefix and solib-search-path
4876 For SunOS and SVR4 shared libraries, you may now set the prefix for
4877 loading absolute shared library symbol files, and the search path for
4878 locating non-absolute shared library symbol files.
4880 * Live range splitting
4882 GDB can now effectively debug code for which GCC has performed live
4883 range splitting as part of its optimization. See gdb/doc/LRS for
4884 more details on the expected format of the stabs information.
4888 GDB's support for the GNU Hurd, including thread debugging, has been
4889 updated to work with current versions of the Hurd.
4893 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4894 instruction set. ARM GDB automatically detects when Thumb
4895 instructions are in use, and adjusts disassembly and backtracing
4900 GDB's MIPS target configurations now handle the MIP16 16-bit
4905 GDB now includes support for overlays; if an executable has been
4906 linked such that multiple sections are based at the same address, GDB
4907 will decide which section to use for symbolic info. You can choose to
4908 control the decision manually, using overlay commands, or implement
4909 additional target-side support and use "overlay load-target" to bring
4910 in the overlay mapping. Do "help overlay" for more detail.
4914 The command "info symbol <address>" displays information about
4915 the symbol at the specified address.
4919 The standard remote protocol now includes an extension that allows
4920 asynchronous collection and display of trace data. This requires
4921 extensive support in the target-side debugging stub. Tracing mode
4922 includes a new interaction mode in GDB and new commands: see the
4923 file tracepoint.c for more details.
4927 Configurations for embedded MIPS now include a simulator contributed
4928 by Cygnus Solutions. The simulator supports the instruction sets
4929 of most MIPS variants.
4933 Sparc configurations may now include the ERC32 simulator contributed
4934 by the European Space Agency. The simulator is not built into
4935 Sparc targets by default; configure with --enable-sim to include it.
4939 For target configurations that may include multiple variants of a
4940 basic architecture (such as MIPS and SH), you may now set the
4941 architecture explicitly. "set arch" sets, "info arch" lists
4942 the possible architectures.
4944 *** Changes in GDB-4.16:
4946 * New native configurations
4948 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4949 M68K NetBSD m68k-*-netbsd*
4950 PowerPC AIX 4.x powerpc-*-aix*
4951 PowerPC MacOS powerpc-*-macos*
4952 PowerPC Windows NT powerpcle-*-cygwin32
4953 RS/6000 AIX 4.x rs6000-*-aix4*
4957 ARM with RDP protocol arm-*-*
4958 I960 with MON960 i960-*-coff
4959 MIPS VxWorks mips*-*-vxworks*
4960 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4961 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4963 Matra Sparclet sparclet-*-*
4967 The powerpc-eabi configuration now includes the PSIM simulator,
4968 contributed by Andrew Cagney, with assistance from Mike Meissner.
4969 PSIM is a very elaborate model of the PowerPC, including not only
4970 basic instruction set execution, but also details of execution unit
4971 performance and I/O hardware. See sim/ppc/README for more details.
4975 GDB now works with Solaris 2.5.
4977 * Windows 95/NT native
4979 GDB will now work as a native debugger on Windows 95 and Windows NT.
4980 To build it from source, you must use the "gnu-win32" environment,
4981 which uses a DLL to emulate enough of Unix to run the GNU tools.
4982 Further information, binaries, and sources are available at
4983 ftp.cygnus.com, under pub/gnu-win32.
4985 * dont-repeat command
4987 If a user-defined command includes the command `dont-repeat', then the
4988 command will not be repeated if the user just types return. This is
4989 useful if the command is time-consuming to run, so that accidental
4990 extra keystrokes don't run the same command many times.
4992 * Send break instead of ^C
4994 The standard remote protocol now includes an option to send a break
4995 rather than a ^C to the target in order to interrupt it. By default,
4996 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4998 * Remote protocol timeout
5000 The standard remote protocol includes a new variable `remotetimeout'
5001 that allows you to set the number of seconds before GDB gives up trying
5002 to read from the target. The default value is 2.
5004 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5006 By default GDB will automatically keep track of objects as they are
5007 loaded and unloaded by the dynamic linker. By using the command `set
5008 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5009 when shared library events occur, thus allowing you to set breakpoints
5010 in shared libraries which are explicitly loaded by the inferior.
5012 Note this feature does not work on hpux8. On hpux9 you must link
5013 /usr/lib/end.o into your program. This feature should work
5014 automatically on hpux10.
5016 * Irix 5.x hardware watchpoint support
5018 Irix 5 configurations now support the use of hardware watchpoints.
5020 * Mips protocol "SYN garbage limit"
5022 When debugging a Mips target using the `target mips' protocol, you
5023 may set the number of characters that GDB will ignore by setting
5024 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5025 every character. The default value is 1050.
5027 * Recording and replaying remote debug sessions
5029 If you set `remotelogfile' to the name of a file, gdb will write to it
5030 a recording of a remote debug session. This recording may then be
5031 replayed back to gdb using "gdbreplay". See gdbserver/README for
5032 details. This is useful when you have a problem with GDB while doing
5033 remote debugging; you can make a recording of the session and send it
5034 to someone else, who can then recreate the problem.
5036 * Speedups for remote debugging
5038 GDB includes speedups for downloading and stepping MIPS systems using
5039 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5040 and more efficient S-record downloading.
5042 * Memory use reductions and statistics collection
5044 GDB now uses less memory and reports statistics about memory usage.
5045 Try the `maint print statistics' command, for example.
5047 *** Changes in GDB-4.15:
5049 * Psymtabs for XCOFF
5051 The symbol reader for AIX GDB now uses partial symbol tables. This
5052 can greatly improve startup time, especially for large executables.
5054 * Remote targets use caching
5056 Remote targets now use a data cache to speed up communication with the
5057 remote side. The data cache could lead to incorrect results because
5058 it doesn't know about volatile variables, thus making it impossible to
5059 debug targets which use memory mapped I/O devices. `set remotecache
5060 off' turns the the data cache off.
5062 * Remote targets may have threads
5064 The standard remote protocol now includes support for multiple threads
5065 in the target system, using new protocol commands 'H' and 'T'. See
5066 gdb/remote.c for details.
5070 If GDB is configured with `--enable-netrom', then it will include
5071 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5072 acts as though it is a bank of ROM on the target board, but you can
5073 write into it over the network. GDB's support consists only of
5074 support for fast loading into the emulated ROM; to debug, you must use
5075 another protocol, such as standard remote protocol. The usual
5076 sequence is something like
5078 target nrom <netrom-hostname>
5080 target remote <netrom-hostname>:1235
5084 GDB now includes support for the Apple Macintosh, as a host only. It
5085 may be run as either an MPW tool or as a standalone application, and
5086 it can debug through the serial port. All the usual GDB commands are
5087 available, but to the target command, you must supply "serial" as the
5088 device type instead of "/dev/ttyXX". See mpw-README in the main
5089 directory for more information on how to build. The MPW configuration
5090 scripts */mpw-config.in support only a few targets, and only the
5091 mips-idt-ecoff target has been tested.
5095 GDB configuration now uses autoconf. This is not user-visible,
5096 but does simplify configuration and building.
5100 GDB now supports hpux10.
5102 *** Changes in GDB-4.14:
5104 * New native configurations
5106 x86 FreeBSD i[345]86-*-freebsd
5107 x86 NetBSD i[345]86-*-netbsd
5108 NS32k NetBSD ns32k-*-netbsd
5109 Sparc NetBSD sparc-*-netbsd
5113 A29K VxWorks a29k-*-vxworks
5114 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5115 CPU32 EST-300 emulator m68*-*-est*
5116 PowerPC ELF powerpc-*-elf
5119 * Alpha OSF/1 support for procfs
5121 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5122 possible to attach to running processes. As the mounting of the /proc
5123 filesystem is optional on the Alpha, GDB automatically determines
5124 the availability of /proc during startup. This can lead to problems
5125 if /proc is unmounted after GDB has been started.
5127 * Arguments to user-defined commands
5129 User commands may accept up to 10 arguments separated by whitespace.
5130 Arguments are accessed within the user command via $arg0..$arg9. A
5133 print $arg0 + $arg1 + $arg2
5135 To execute the command use:
5138 Defines the command "adder" which prints the sum of its three arguments.
5139 Note the arguments are text substitutions, so they may reference variables,
5140 use complex expressions, or even perform inferior function calls.
5142 * New `if' and `while' commands
5144 This makes it possible to write more sophisticated user-defined
5145 commands. Both commands take a single argument, which is the
5146 expression to evaluate, and must be followed by the commands to
5147 execute, one per line, if the expression is nonzero, the list being
5148 terminated by the word `end'. The `if' command list may include an
5149 `else' word, which causes the following commands to be executed only
5150 if the expression is zero.
5152 * Fortran source language mode
5154 GDB now includes partial support for Fortran 77. It will recognize
5155 Fortran programs and can evaluate a subset of Fortran expressions, but
5156 variables and functions may not be handled correctly. GDB will work
5157 with G77, but does not yet know much about symbols emitted by other
5160 * Better HPUX support
5162 Most debugging facilities now work on dynamic executables for HPPAs
5163 running hpux9 or later. You can attach to running dynamically linked
5164 processes, but by default the dynamic libraries will be read-only, so
5165 for instance you won't be able to put breakpoints in them. To change
5166 that behavior do the following before running the program:
5172 This will cause the libraries to be mapped private and read-write.
5173 To revert to the normal behavior, do this:
5179 You cannot set breakpoints or examine data in the library until after
5180 the library is loaded if the function/data symbols do not have
5183 GDB can now also read debug symbols produced by the HP C compiler on
5184 HPPAs (sorry, no C++, Fortran or 68k support).
5186 * Target byte order now dynamically selectable
5188 You can choose which byte order to use with a target system, via the
5189 commands "set endian big" and "set endian little", and you can see the
5190 current setting by using "show endian". You can also give the command
5191 "set endian auto", in which case GDB will use the byte order
5192 associated with the executable. Currently, only embedded MIPS
5193 configurations support dynamic selection of target byte order.
5195 * New DOS host serial code
5197 This version uses DPMI interrupts to handle buffered I/O, so you
5198 no longer need to run asynctsr when debugging boards connected to
5201 *** Changes in GDB-4.13:
5203 * New "complete" command
5205 This lists all the possible completions for the rest of the line, if it
5206 were to be given as a command itself. This is intended for use by emacs.
5208 * Trailing space optional in prompt
5210 "set prompt" no longer adds a space for you after the prompt you set. This
5211 allows you to set a prompt which ends in a space or one that does not.
5213 * Breakpoint hit counts
5215 "info break" now displays a count of the number of times the breakpoint
5216 has been hit. This is especially useful in conjunction with "ignore"; you
5217 can ignore a large number of breakpoint hits, look at the breakpoint info
5218 to see how many times the breakpoint was hit, then run again, ignoring one
5219 less than that number, and this will get you quickly to the last hit of
5222 * Ability to stop printing at NULL character
5224 "set print null-stop" will cause GDB to stop printing the characters of
5225 an array when the first NULL is encountered. This is useful when large
5226 arrays actually contain only short strings.
5228 * Shared library breakpoints
5230 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5231 breakpoints in shared libraries before the executable is run.
5233 * Hardware watchpoints
5235 There is a new hardware breakpoint for the watch command for sparclite
5236 targets. See gdb/sparclite/hw_breakpoint.note.
5238 Hardware watchpoints are also now supported under GNU/Linux.
5242 Annotations have been added. These are for use with graphical interfaces,
5243 and are still experimental. Currently only gdba.el uses these.
5245 * Improved Irix 5 support
5247 GDB now works properly with Irix 5.2.
5249 * Improved HPPA support
5251 GDB now works properly with the latest GCC and GAS.
5253 * New native configurations
5255 Sequent PTX4 i[34]86-sequent-ptx4
5256 HPPA running OSF/1 hppa*-*-osf*
5257 Atari TT running SVR4 m68*-*-sysv4*
5258 RS/6000 LynxOS rs6000-*-lynxos*
5262 OS/9000 i[34]86-*-os9k
5263 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5266 * Hitachi SH7000 and E7000-PC ICE support
5268 There is now support for communicating with the Hitachi E7000-PC ICE.
5269 This is available automatically when GDB is configured for the SH.
5273 As usual, a variety of small fixes and improvements, both generic
5274 and configuration-specific. See the ChangeLog for more detail.
5276 *** Changes in GDB-4.12:
5278 * Irix 5 is now supported
5282 GDB-4.12 on the HPPA has a number of changes which make it unable
5283 to debug the output from the currently released versions of GCC and
5284 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5285 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5286 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5289 *** Changes in GDB-4.11:
5291 * User visible changes:
5295 The "set remotedebug" option is now consistent between the mips remote
5296 target, remote targets using the gdb-specific protocol, UDI (AMD's
5297 debug protocol for the 29k) and the 88k bug monitor. It is now an
5298 integer specifying a debug level (normally 0 or 1, but 2 means more
5299 debugging info for the mips target).
5301 * DEC Alpha native support
5303 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5304 debug info, but GDB works fairly well with the DEC compiler and should
5305 work with a future GCC release. See the README file for a few
5306 Alpha-specific notes.
5308 * Preliminary thread implementation
5310 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5312 * LynxOS native and target support for 386
5314 This release has been hosted on LynxOS 2.2, and also can be configured
5315 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5318 * Improvements in C++ mangling/demangling.
5320 This release has much better g++ debugging, specifically in name
5321 mangling/demangling, virtual function calls, print virtual table,
5322 call methods, ...etc.
5324 *** Changes in GDB-4.10:
5326 * User visible changes:
5328 Remote debugging using the GDB-specific (`target remote') protocol now
5329 supports the `load' command. This is only useful if you have some
5330 other way of getting the stub to the target system, and you can put it
5331 somewhere in memory where it won't get clobbered by the download.
5333 Filename completion now works.
5335 When run under emacs mode, the "info line" command now causes the
5336 arrow to point to the line specified. Also, "info line" prints
5337 addresses in symbolic form (as well as hex).
5339 All vxworks based targets now support a user settable option, called
5340 vxworks-timeout. This option represents the number of seconds gdb
5341 should wait for responses to rpc's. You might want to use this if
5342 your vxworks target is, perhaps, a slow software simulator or happens
5343 to be on the far side of a thin network line.
5347 This release contains support for using a DEC alpha as a GDB host for
5348 cross debugging. Native alpha debugging is not supported yet.
5351 *** Changes in GDB-4.9:
5355 This is the first GDB release which is accompanied by a matching testsuite.
5356 The testsuite requires installation of dejagnu, which should be available
5357 via ftp from most sites that carry GNU software.
5361 'Cfront' style demangling has had its name changed to 'ARM' style, to
5362 emphasize that it was written from the specifications in the C++ Annotated
5363 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5364 disclaimers, it still generated too much confusion with users attempting to
5365 use gdb with AT&T cfront.
5369 GDB now uses a standard remote interface to a simulator library.
5370 So far, the library contains simulators for the Zilog Z8001/2, the
5371 Hitachi H8/300, H8/500 and Super-H.
5373 * New targets supported
5375 H8/300 simulator h8300-hitachi-hms or h8300hms
5376 H8/500 simulator h8500-hitachi-hms or h8500hms
5377 SH simulator sh-hitachi-hms or sh
5378 Z8000 simulator z8k-zilog-none or z8ksim
5379 IDT MIPS board over serial line mips-idt-ecoff
5381 Cross-debugging to GO32 targets is supported. It requires a custom
5382 version of the i386-stub.c module which is integrated with the
5383 GO32 memory extender.
5385 * New remote protocols
5387 MIPS remote debugging protocol.
5389 * New source languages supported
5391 This version includes preliminary support for Chill, a Pascal like language
5392 used by telecommunications companies. Chill support is also being integrated
5393 into the GNU compiler, but we don't know when it will be publically available.
5396 *** Changes in GDB-4.8:
5398 * HP Precision Architecture supported
5400 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5401 version of this support was available as a set of patches from the
5402 University of Utah. GDB does not support debugging of programs
5403 compiled with the HP compiler, because HP will not document their file
5404 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5405 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5407 Many problems in the preliminary version have been fixed.
5409 * Faster and better demangling
5411 We have improved template demangling and fixed numerous bugs in the GNU style
5412 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5413 character types (wchar_t) are now supported. Demangling of each symbol is now
5414 only done once, and is cached when the symbol table for a file is read in.
5415 This results in a small increase in memory usage for C programs, a moderate
5416 increase in memory usage for C++ programs, and a fantastic speedup in
5419 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5420 from the specifications in the Annotated Reference Manual, which AT&T's
5421 compiler does not actually implement.
5423 * G++ multiple inheritance compiler problem
5425 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5426 inheritance lattices was reworked to properly discover ambiguities. We
5427 recently found an example which causes this new algorithm to fail in a
5428 very subtle way, producing bad debug information for those classes.
5429 The file 'gcc.patch' (in this directory) can be applied to gcc to
5430 circumvent the problem. A future GCC release will contain a complete
5433 The previous G++ debug info problem (mentioned below for the gdb-4.7
5434 release) is fixed in gcc version 2.3.2.
5436 * Improved configure script
5438 The `configure' script will now attempt to guess your system type if
5439 you don't supply a host system type. The old scheme of supplying a
5440 host system triplet is preferable over using this. All the magic is
5441 done in the new `config.guess' script. Examine it for details.
5443 We have also brought our configure script much more in line with the FSF's
5444 version. It now supports the --with-xxx options. In particular,
5445 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5446 The resulting GDB will not be able to read arbitrary object file formats --
5447 only the format ``expected'' to be used on the configured target system.
5448 We hope to make this the default in a future release.
5450 * Documentation improvements
5452 There's new internal documentation on how to modify GDB, and how to
5453 produce clean changes to the code. We implore people to read it
5454 before submitting changes.
5456 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5457 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5458 `info' files are also provided. To build `info' files from scratch,
5459 you will need the latest `makeinfo' release, which will be available in
5460 a future texinfo-X.Y release.
5462 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5463 We're not sure exactly which versions have this problem, but it has
5464 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5465 or better. If that isn't possible, there is a patch in
5466 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5467 around this problem.
5471 GDB now supports array constants that can be used in expressions typed in by
5472 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5473 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5476 The new directory `gdb/sparclite' contains a program that demonstrates
5477 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5479 * New native hosts supported
5481 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5482 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5484 * New targets supported
5486 AMD 29k family via UDI a29k-amd-udi or udi29k
5488 * New file formats supported
5490 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5491 HPUX core files, and SCO 3.2v2 core files.
5495 Attaching to processes now works again; thanks for the many bug reports.
5497 We have also stomped on a bunch of core dumps caused by
5498 printf_filtered("%s") problems.
5500 We eliminated a copyright problem on the rpc and ptrace header files
5501 for VxWorks, which was discovered at the last minute during the 4.7
5502 release. You should now be able to build a VxWorks GDB.
5504 You can now interrupt gdb while an attached process is running. This
5505 will cause the attached process to stop, and give control back to GDB.
5507 We fixed problems caused by using too many file descriptors
5508 for reading symbols from object files and libraries. This was
5509 especially a problem for programs that used many (~100) shared
5512 The `step' command now only enters a subroutine if there is line number
5513 information for the subroutine. Otherwise it acts like the `next'
5514 command. Previously, `step' would enter subroutines if there was
5515 any debugging information about the routine. This avoids problems
5516 when using `cc -g1' on MIPS machines.
5518 * Internal improvements
5520 GDB's internal interfaces have been improved to make it easier to support
5521 debugging of multiple languages in the future.
5523 GDB now uses a common structure for symbol information internally.
5524 Minimal symbols (derived from linkage symbols in object files), partial
5525 symbols (from a quick scan of debug information), and full symbols
5526 contain a common subset of information, making it easier to write
5527 shared code that handles any of them.
5529 * New command line options
5531 We now accept --silent as an alias for --quiet.
5535 The memory-mapped-malloc library is now licensed under the GNU Library
5536 General Public License.
5538 *** Changes in GDB-4.7:
5540 * Host/native/target split
5542 GDB has had some major internal surgery to untangle the support for
5543 hosts and remote targets. Now, when you configure GDB for a remote
5544 target, it will no longer load in all of the support for debugging
5545 local programs on the host. When fully completed and tested, this will
5546 ensure that arbitrary host/target combinations are possible.
5548 The primary conceptual shift is to separate the non-portable code in
5549 GDB into three categories. Host specific code is required any time GDB
5550 is compiled on that host, regardless of the target. Target specific
5551 code relates to the peculiarities of the target, but can be compiled on
5552 any host. Native specific code is everything else: it can only be
5553 built when the host and target are the same system. Child process
5554 handling and core file support are two common `native' examples.
5556 GDB's use of /proc for controlling Unix child processes is now cleaner.
5557 It has been split out into a single module under the `target_ops' vector,
5558 plus two native-dependent functions for each system that uses /proc.
5560 * New hosts supported
5562 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5563 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5564 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5566 * New targets supported
5568 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5569 68030 and CPU32 m68030-*-*, m68332-*-*
5571 * New native hosts supported
5573 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5574 (386bsd is not well tested yet)
5575 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5577 * New file formats supported
5579 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5580 supports reading of `a.out.adobe' object files, which are an a.out
5581 format extended with minimal information about multiple sections.
5585 `show copying' is the same as the old `info copying'.
5586 `show warranty' is the same as `info warrantee'.
5587 These were renamed for consistency. The old commands continue to work.
5589 `info handle' is a new alias for `info signals'.
5591 You can now define pre-command hooks, which attach arbitrary command
5592 scripts to any command. The commands in the hook will be executed
5593 prior to the user's command. You can also create a hook which will be
5594 executed whenever the program stops. See gdb.texinfo.
5598 We now deal with Cfront style name mangling, and can even extract type
5599 info from mangled symbols. GDB can automatically figure out which
5600 symbol mangling style your C++ compiler uses.
5602 Calling of methods and virtual functions has been improved as well.
5606 The crash that occured when debugging Sun Ansi-C compiled binaries is
5607 fixed. This was due to mishandling of the extra N_SO stabs output
5610 We also finally got Ultrix 4.2 running in house, and fixed core file
5611 support, with help from a dozen people on the net.
5613 John M. Farrell discovered that the reason that single-stepping was so
5614 slow on all of the Mips based platforms (primarily SGI and DEC) was
5615 that we were trying to demangle and lookup a symbol used for internal
5616 purposes on every instruction that was being stepped through. Changing
5617 the name of that symbol so that it couldn't be mistaken for a C++
5618 mangled symbol sped things up a great deal.
5620 Rich Pixley sped up symbol lookups in general by getting much smarter
5621 about when C++ symbol mangling is necessary. This should make symbol
5622 completion (TAB on the command line) much faster. It's not as fast as
5623 we'd like, but it's significantly faster than gdb-4.6.
5627 A new user controllable variable 'call_scratch_address' can
5628 specify the location of a scratch area to be used when GDB
5629 calls a function in the target. This is necessary because the
5630 usual method of putting the scratch area on the stack does not work
5631 in systems that have separate instruction and data spaces.
5633 We integrated changes to support the 29k UDI (Universal Debugger
5634 Interface), but discovered at the last minute that we didn't have all
5635 of the appropriate copyright paperwork. We are working with AMD to
5636 resolve this, and hope to have it available soon.
5640 We have sped up the remote serial line protocol, especially for targets
5641 with lots of registers. It now supports a new `expedited status' ('T')
5642 message which can be used in place of the existing 'S' status message.
5643 This allows the remote stub to send only the registers that GDB
5644 needs to make a quick decision about single-stepping or conditional
5645 breakpoints, eliminating the need to fetch the entire register set for
5646 each instruction being stepped through.
5648 The GDB remote serial protocol now implements a write-through cache for
5649 registers, only re-reading the registers if the target has run.
5651 There is also a new remote serial stub for SPARC processors. You can
5652 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5653 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5654 processor with a serial port.
5658 Configure.in files have become much easier to read and modify. A new
5659 `table driven' format makes it more obvious what configurations are
5660 supported, and what files each one uses.
5664 There is a new opcodes library which will eventually contain all of the
5665 disassembly routines and opcode tables. At present, it only contains
5666 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5667 disassembler (binutils/objdump) to share these routines.
5669 The libiberty library is now copylefted under the GNU Library General
5670 Public License. This allows more liberal use, and was done so libg++
5671 can use it. This makes no difference to GDB, since the Library License
5672 grants all the rights from the General Public License.
5676 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5677 reference to the stabs symbol info used by the debugger. It is (as far
5678 as we know) the only published document on this fascinating topic. We
5679 encourage you to read it, compare it to the stabs information on your
5680 system, and send improvements on the document in general (to
5681 bug-gdb@prep.ai.mit.edu).
5683 And, of course, many bugs have been fixed.
5686 *** Changes in GDB-4.6:
5688 * Better support for C++ function names
5690 GDB now accepts as input the "demangled form" of C++ overloaded function
5691 names and member function names, and can do command completion on such names
5692 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5693 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5694 Make use of command completion, it is your friend.
5696 GDB also now accepts a variety of C++ mangled symbol formats. They are
5697 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5698 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5699 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5700 for the list of formats.
5702 * G++ symbol mangling problem
5704 Recent versions of gcc have a bug in how they emit debugging information for
5705 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5706 directory) can be applied to gcc to fix the problem. Alternatively, if you
5707 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5708 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5709 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5712 * New 'maintenance' command
5714 All of the commands related to hacking GDB internals have been moved out of
5715 the main command set, and now live behind the 'maintenance' command. This
5716 can also be abbreviated as 'mt'. The following changes were made:
5718 dump-me -> maintenance dump-me
5719 info all-breakpoints -> maintenance info breakpoints
5720 printmsyms -> maintenance print msyms
5721 printobjfiles -> maintenance print objfiles
5722 printpsyms -> maintenance print psymbols
5723 printsyms -> maintenance print symbols
5725 The following commands are new:
5727 maintenance demangle Call internal GDB demangler routine to
5728 demangle a C++ link name and prints the result.
5729 maintenance print type Print a type chain for a given symbol
5731 * Change to .gdbinit file processing
5733 We now read the $HOME/.gdbinit file before processing the argv arguments
5734 (e.g. reading symbol files or core files). This allows global parameters to
5735 be set, which will apply during the symbol reading. The ./.gdbinit is still
5736 read after argv processing.
5738 * New hosts supported
5740 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5742 GNU/Linux support i386-unknown-linux or linux
5744 We are also including code to support the HP/PA running BSD and HPUX. This
5745 is almost guaranteed not to work, as we didn't have time to test or build it
5746 for this release. We are including it so that the more adventurous (or
5747 masochistic) of you can play with it. We also had major problems with the
5748 fact that the compiler that we got from HP doesn't support the -g option.
5751 * New targets supported
5753 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5755 * More smarts about finding #include files
5757 GDB now remembers the compilation directory for all include files, and for
5758 all files from which C is generated (like yacc and lex sources). This
5759 greatly improves GDB's ability to find yacc/lex sources, and include files,
5760 especially if you are debugging your program from a directory different from
5761 the one that contains your sources.
5763 We also fixed a bug which caused difficulty with listing and setting
5764 breakpoints in include files which contain C code. (In the past, you had to
5765 try twice in order to list an include file that you hadn't looked at before.)
5767 * Interesting infernals change
5769 GDB now deals with arbitrary numbers of sections, where the symbols for each
5770 section must be relocated relative to that section's landing place in the
5771 target's address space. This work was needed to support ELF with embedded
5772 stabs used by Solaris-2.0.
5774 * Bug fixes (of course!)
5776 There have been loads of fixes for the following things:
5777 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5778 i960, stabs, DOS(GO32), procfs, etc...
5780 See the ChangeLog for details.
5782 *** Changes in GDB-4.5:
5784 * New machines supported (host and target)
5786 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5788 SGI Irix-4.x mips-sgi-irix4 or iris4
5790 * New malloc package
5792 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5793 Mmalloc is capable of handling mutiple heaps of memory. It is also
5794 capable of saving a heap to a file, and then mapping it back in later.
5795 This can be used to greatly speedup the startup of GDB by using a
5796 pre-parsed symbol table which lives in a mmalloc managed heap. For
5797 more details, please read mmalloc/mmalloc.texi.
5801 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5802 'help info proc' for details.
5804 * MIPS ecoff symbol table format
5806 The code that reads MIPS symbol table format is now supported on all hosts.
5807 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5810 * File name changes for MS-DOS
5812 Many files in the config directories have been renamed to make it easier to
5813 support GDB on MS-DOSe systems (which have very restrictive file name
5814 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5815 environment) is close to working but has some remaining problems. Note
5816 that debugging of DOS programs is not supported, due to limitations
5817 in the ``operating system'', but it can be used to host cross-debugging.
5819 * Cross byte order fixes
5821 Many fixes have been made to support cross debugging of Sparc and MIPS
5822 targets from hosts whose byte order differs.
5824 * New -mapped and -readnow options
5826 If memory-mapped files are available on your system through the 'mmap'
5827 system call, you can use the -mapped option on the `file' or
5828 `symbol-file' commands to cause GDB to write the symbols from your
5829 program into a reusable file. If the program you are debugging is
5830 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5831 Future GDB debugging sessions will notice the presence of this file,
5832 and will quickly map in symbol information from it, rather than reading
5833 the symbol table from the executable program. Using the '-mapped'
5834 option in a GDB `file' or `symbol-file' command has the same effect as
5835 starting GDB with the '-mapped' command-line option.
5837 You can cause GDB to read the entire symbol table immediately by using
5838 the '-readnow' option with any of the commands that load symbol table
5839 information (or on the GDB command line). This makes the command
5840 slower, but makes future operations faster.
5842 The -mapped and -readnow options are typically combined in order to
5843 build a `fred.syms' file that contains complete symbol information.
5844 A simple GDB invocation to do nothing but build a `.syms' file for future
5847 gdb -batch -nx -mapped -readnow programname
5849 The `.syms' file is specific to the host machine on which GDB is run.
5850 It holds an exact image of GDB's internal symbol table. It cannot be
5851 shared across multiple host platforms.
5853 * longjmp() handling
5855 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5856 siglongjmp() without losing control. This feature has not yet been ported to
5857 all systems. It currently works on many 386 platforms, all MIPS-based
5858 platforms (SGI, DECstation, etc), and Sun3/4.
5862 Preliminary work has been put in to support the new Solaris OS from Sun. At
5863 this time, it can control and debug processes, but it is not capable of
5868 As always, many many bug fixes. The major areas were with g++, and mipsread.
5869 People using the MIPS-based platforms should experience fewer mysterious
5870 crashes and trashed symbol tables.
5872 *** Changes in GDB-4.4:
5874 * New machines supported (host and target)
5876 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5878 BSD Reno on Vax vax-dec-bsd
5879 Ultrix on Vax vax-dec-ultrix
5881 * New machines supported (target)
5883 AMD 29000 embedded, using EBMON a29k-none-none
5887 GDB continues to improve its handling of C++. `References' work better.
5888 The demangler has also been improved, and now deals with symbols mangled as
5889 per the Annotated C++ Reference Guide.
5891 GDB also now handles `stabs' symbol information embedded in MIPS
5892 `ecoff' symbol tables. Since the ecoff format was not easily
5893 extensible to handle new languages such as C++, this appeared to be a
5894 good way to put C++ debugging info into MIPS binaries. This option
5895 will be supported in the GNU C compiler, version 2, when it is
5898 * New features for SVR4
5900 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5901 shared libraries. Debugging dynamically linked programs should present
5902 only minor differences from debugging statically linked programs.
5904 The `info proc' command will print out information about any process
5905 on an SVR4 system (including the one you are debugging). At the moment,
5906 it prints the address mappings of the process.
5908 If you bring up GDB on another SVR4 system, please send mail to
5909 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5911 * Better dynamic linking support in SunOS
5913 Reading symbols from shared libraries which contain debugging symbols
5914 now works properly. However, there remain issues such as automatic
5915 skipping of `transfer vector' code during function calls, which
5916 make it harder to debug code in a shared library, than to debug the
5917 same code linked statically.
5921 GDB is now using the latest `getopt' routines from the FSF. This
5922 version accepts the -- prefix for options with long names. GDB will
5923 continue to accept the old forms (-option and +option) as well.
5924 Various single letter abbreviations for options have been explicity
5925 added to the option table so that they won't get overshadowed in the
5926 future by other options that begin with the same letter.
5930 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5931 Many assorted bugs have been handled. Many more remain to be handled.
5932 See the various ChangeLog files (primarily in gdb and bfd) for details.
5935 *** Changes in GDB-4.3:
5937 * New machines supported (host and target)
5939 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5940 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5941 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5943 * Almost SCO Unix support
5945 We had hoped to support:
5946 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5947 (except for core file support), but we discovered very late in the release
5948 that it has problems with process groups that render gdb unusable. Sorry
5949 about that. I encourage people to fix it and post the fixes.
5951 * Preliminary ELF and DWARF support
5953 GDB can read ELF object files on System V Release 4, and can handle
5954 debugging records for C, in DWARF format, in ELF files. This support
5955 is preliminary. If you bring up GDB on another SVR4 system, please
5956 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5961 GDB now uses the latest `readline' library. One user-visible change
5962 is that two tabs will list possible command completions, which previously
5963 required typing M-? (meta-question mark, or ESC ?).
5967 The `stepi' bug that many of you noticed has been squashed.
5968 Many bugs in C++ have been handled. Many more remain to be handled.
5969 See the various ChangeLog files (primarily in gdb and bfd) for details.
5971 * State of the MIPS world (in case you wondered):
5973 GDB can understand the symbol tables emitted by the compilers
5974 supplied by most vendors of MIPS-based machines, including DEC. These
5975 symbol tables are in a format that essentially nobody else uses.
5977 Some versions of gcc come with an assembler post-processor called
5978 mips-tfile. This program is required if you want to do source-level
5979 debugging of gcc-compiled programs. I believe FSF does not ship
5980 mips-tfile with gcc version 1, but it will eventually come with gcc
5983 Debugging of g++ output remains a problem. g++ version 1.xx does not
5984 really support it at all. (If you're lucky, you should be able to get
5985 line numbers and stack traces to work, but no parameters or local
5986 variables.) With some work it should be possible to improve the
5989 When gcc version 2 is released, you will have somewhat better luck.
5990 However, even then you will get confusing results for inheritance and
5993 We will eventually provide full debugging of g++ output on
5994 DECstations. This will probably involve some kind of stabs-in-ecoff
5995 encapulation, but the details have not been worked out yet.
5998 *** Changes in GDB-4.2:
6000 * Improved configuration
6002 Only one copy of `configure' exists now, and it is not self-modifying.
6003 Porting BFD is simpler.
6007 The `step' and `next' commands now only stop at the first instruction
6008 of a source line. This prevents the multiple stops that used to occur
6009 in switch statements, for-loops, etc. `Step' continues to stop if a
6010 function that has debugging information is called within the line.
6014 Lots of small bugs fixed. More remain.
6016 * New host supported (not target)
6018 Intel 386 PC clone running Mach i386-none-mach
6021 *** Changes in GDB-4.1:
6023 * Multiple source language support
6025 GDB now has internal scaffolding to handle several source languages.
6026 It determines the type of each source file from its filename extension,
6027 and will switch expression parsing and number formatting to match the
6028 language of the function in the currently selected stack frame.
6029 You can also specifically set the language to be used, with
6030 `set language c' or `set language modula-2'.
6034 GDB now has preliminary support for the GNU Modula-2 compiler,
6035 currently under development at the State University of New York at
6036 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6037 continue through the fall of 1991 and into 1992.
6039 Other Modula-2 compilers are currently not supported, and attempting to
6040 debug programs compiled with them will likely result in an error as the
6041 symbol table is read. Feel free to work on it, though!
6043 There are hooks in GDB for strict type checking and range checking,
6044 in the `Modula-2 philosophy', but they do not currently work.
6048 GDB can now write to executable and core files (e.g. patch
6049 a variable's value). You must turn this switch on, specify
6050 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6051 by assigning a new value to a variable. Modifications take
6054 * Automatic SunOS shared library reading
6056 When you run your program, GDB automatically determines where its
6057 shared libraries (if any) have been loaded, and reads their symbols.
6058 The `share' command is no longer needed. This also works when
6059 examining core files.
6063 You can specify the number of lines that the `list' command shows.
6066 * New machines supported (host and target)
6068 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6069 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6070 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6072 * New hosts supported (not targets)
6074 IBM RT/PC: romp-ibm-aix or rtpc
6076 * New targets supported (not hosts)
6078 AMD 29000 embedded with COFF a29k-none-coff
6079 AMD 29000 embedded with a.out a29k-none-aout
6080 Ultracomputer remote kernel debug a29k-nyu-kern
6082 * New remote interfaces
6088 *** Changes in GDB-4.0:
6092 Wide output is wrapped at good places to make the output more readable.
6094 Gdb now supports cross-debugging from a host machine of one type to a
6095 target machine of another type. Communication with the target system
6096 is over serial lines. The ``target'' command handles connecting to the
6097 remote system; the ``load'' command will download a program into the
6098 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6099 also supports debugging of realtime processes running under VxWorks,
6100 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6101 stub on the target system.
6103 New CPUs supported include the AMD 29000 and Intel 960.
6105 GDB now reads object files and symbol tables via a ``binary file''
6106 library, which allows a single copy of GDB to debug programs of multiple
6107 object file types such as a.out and coff.
6109 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6110 refcard.dvi and refcard.ps are available to format it).
6113 * Control-Variable user interface simplified
6115 All variables that control the operation of the debugger can be set
6116 by the ``set'' command, and displayed by the ``show'' command.
6118 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6119 ``Show prompt'' produces the response:
6120 Gdb's prompt is new-gdb=>.
6122 What follows are the NEW set commands. The command ``help set'' will
6123 print a complete list of old and new set commands. ``help set FOO''
6124 will give a longer description of the variable FOO. ``show'' will show
6125 all of the variable descriptions and their current settings.
6127 confirm on/off: Enables warning questions for operations that are
6128 hard to recover from, e.g. rerunning the program while
6129 it is already running. Default is ON.
6131 editing on/off: Enables EMACS style command line editing
6132 of input. Previous lines can be recalled with
6133 control-P, the current line can be edited with control-B,
6134 you can search for commands with control-R, etc.
6137 history filename NAME: NAME is where the gdb command history
6138 will be stored. The default is .gdb_history,
6139 or the value of the environment variable
6142 history size N: The size, in commands, of the command history. The
6143 default is 256, or the value of the environment variable
6146 history save on/off: If this value is set to ON, the history file will
6147 be saved after exiting gdb. If set to OFF, the
6148 file will not be saved. The default is OFF.
6150 history expansion on/off: If this value is set to ON, then csh-like
6151 history expansion will be performed on
6152 command line input. The default is OFF.
6154 radix N: Sets the default radix for input and output. It can be set
6155 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6156 in the current radix, so "set radix 10" is always a no-op.
6158 height N: This integer value is the number of lines on a page. Default
6159 is 24, the current `stty rows'' setting, or the ``li#''
6160 setting from the termcap entry matching the environment
6163 width N: This integer value is the number of characters on a line.
6164 Default is 80, the current `stty cols'' setting, or the ``co#''
6165 setting from the termcap entry matching the environment
6168 Note: ``set screensize'' is obsolete. Use ``set height'' and
6169 ``set width'' instead.
6171 print address on/off: Print memory addresses in various command displays,
6172 such as stack traces and structure values. Gdb looks
6173 more ``symbolic'' if you turn this off; it looks more
6174 ``machine level'' with it on. Default is ON.
6176 print array on/off: Prettyprint arrays. New convenient format! Default
6179 print demangle on/off: Print C++ symbols in "source" form if on,
6182 print asm-demangle on/off: Same, for assembler level printouts
6185 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6188 * Support for Epoch Environment.
6190 The epoch environment is a version of Emacs v18 with windowing. One
6191 new command, ``inspect'', is identical to ``print'', except that if you
6192 are running in the epoch environment, the value is printed in its own
6196 * Support for Shared Libraries
6198 GDB can now debug programs and core files that use SunOS shared libraries.
6199 Symbols from a shared library cannot be referenced
6200 before the shared library has been linked with the program (this
6201 happens after you type ``run'' and before the function main() is entered).
6202 At any time after this linking (including when examining core files
6203 from dynamically linked programs), gdb reads the symbols from each
6204 shared library when you type the ``sharedlibrary'' command.
6205 It can be abbreviated ``share''.
6207 sharedlibrary REGEXP: Load shared object library symbols for files
6208 matching a unix regular expression. No argument
6209 indicates to load symbols for all shared libraries.
6211 info sharedlibrary: Status of loaded shared libraries.
6216 A watchpoint stops execution of a program whenever the value of an
6217 expression changes. Checking for this slows down execution
6218 tremendously whenever you are in the scope of the expression, but is
6219 quite useful for catching tough ``bit-spreader'' or pointer misuse
6220 problems. Some machines such as the 386 have hardware for doing this
6221 more quickly, and future versions of gdb will use this hardware.
6223 watch EXP: Set a watchpoint (breakpoint) for an expression.
6225 info watchpoints: Information about your watchpoints.
6227 delete N: Deletes watchpoint number N (same as breakpoints).
6228 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6229 enable N: Re-enables watchpoint number N (same as breakpoints).
6232 * C++ multiple inheritance
6234 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6237 * C++ exception handling
6239 Gdb now supports limited C++ exception handling. Besides the existing
6240 ability to breakpoint on an exception handler, gdb can breakpoint on
6241 the raising of an exception (before the stack is peeled back to the
6244 catch FOO: If there is a FOO exception handler in the dynamic scope,
6245 set a breakpoint to catch exceptions which may be raised there.
6246 Multiple exceptions (``catch foo bar baz'') may be caught.
6248 info catch: Lists all exceptions which may be caught in the
6249 current stack frame.
6252 * Minor command changes
6254 The command ``call func (arg, arg, ...)'' now acts like the print
6255 command, except it does not print or save a value if the function's result
6256 is void. This is similar to dbx usage.
6258 The ``up'' and ``down'' commands now always print the frame they end up
6259 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6260 frames without printing.
6262 * New directory command
6264 'dir' now adds directories to the FRONT of the source search path.
6265 The path starts off empty. Source files that contain debug information
6266 about the directory in which they were compiled can be found even
6267 with an empty path; Sun CC and GCC include this information. If GDB can't
6268 find your source file in the current directory, type "dir .".
6270 * Configuring GDB for compilation
6272 For normal use, type ``./configure host''. See README or gdb.texinfo
6275 GDB now handles cross debugging. If you are remotely debugging between
6276 two different machines, type ``./configure host -target=targ''.
6277 Host is the machine where GDB will run; targ is the machine
6278 where the program that you are debugging will run.