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
23 maint set target-non-stop (on|off|auto)
24 maint show target-non-stop
25 Control whether GDB targets always operate in non-stop mode even if
26 "set non-stop" is "off". The default is "auto", meaning non-stop
27 mode is enabled if supported by the target.
30 maint show bfd-sharing
31 Control the reuse of bfd objects.
35 Control display of debugging info regarding bfd caching.
37 set remote multiprocess-extensions-packet
38 show remote multiprocess-extensions-packet
39 Set/show the use of the remote protocol multiprocess extensions.
41 * The "disassemble" command accepts a new modifier: /s.
42 It prints mixed source+disassembly like /m with two differences:
43 - disassembled instructions are now printed in program order, and
44 - and source for all relevant files is now printed.
45 The "/m" option is now considered deprecated: its "source-centric"
46 output hasn't proved useful in practice.
48 * Support for various ROM monitors has been removed:
50 target dbug dBUG ROM monitor for Motorola ColdFire
51 target picobug Motorola picobug monitor
52 target dink32 DINK32 ROM monitor for PowerPC
53 target m32r Renesas M32R/D ROM monitor
54 target mon2000 mon2000 ROM monitor
55 target ppcbug PPCBUG ROM monitor for PowerPC
57 * Support for reading/writing memory and extracting values on architectures
58 whose memory is addressable in units of any integral multiple of 8 bits.
63 Indicates that an exec system call was executed.
65 exec-events feature in qSupported
66 The qSupported packet allows GDB to request support for exec
67 events using the new 'gdbfeature' exec-event, and the qSupported
68 response can contain the corresponding 'stubfeature'. Set and
69 show commands can be used to display whether these features are enabled.
71 * Extended-remote exec events
73 ** GDB now has support for exec events on extended-remote Linux targets.
74 For such targets with Linux kernels 2.5.46 and later, this enables
75 follow-exec-mode and exec catchpoints.
77 set remote exec-event-feature-packet
78 show remote exec-event-feature-packet
79 Set/show the use of the remote exec event feature.
81 *** Changes in GDB 7.10
83 * Support for process record-replay and reverse debugging on aarch64*-linux*
84 targets has been added. GDB now supports recording of A64 instruction set
85 including advance SIMD instructions.
87 * Support for Sun's version of the "stabs" debug file format has been removed.
89 * GDB now honors the content of the file /proc/PID/coredump_filter
90 (PID is the process ID) on GNU/Linux systems. This file can be used
91 to specify the types of memory mappings that will be included in a
92 corefile. For more information, please refer to the manual page of
93 "core(5)". GDB also has a new command: "set use-coredump-filter
94 on|off". It allows to set whether GDB will read the content of the
95 /proc/PID/coredump_filter file when generating a corefile.
97 * The "info os" command on GNU/Linux can now display information on
99 "info os cpus" Listing of all cpus/cores on the system
101 * GDB has two new commands: "set serial parity odd|even|none" and
102 "show serial parity". These allows to set or show parity for the
105 * The "info source" command now displays the producer string if it was
106 present in the debug info. This typically includes the compiler version
107 and may include things like its command line arguments.
109 * The "info dll", an alias of the "info sharedlibrary" command,
110 is now available on all platforms.
112 * Directory names supplied to the "set sysroot" commands may be
113 prefixed with "target:" to tell GDB to access shared libraries from
114 the target system, be it local or remote. This replaces the prefix
115 "remote:". The default sysroot has been changed from "" to
116 "target:". "remote:" is automatically converted to "target:" for
117 backward compatibility.
119 * The system root specified by "set sysroot" will be prepended to the
120 filename of the main executable (if reported to GDB as absolute by
121 the operating system) when starting processes remotely, and when
122 attaching to already-running local or remote processes.
124 * GDB now supports automatic location and retrieval of executable
125 files from remote targets. Remote debugging can now be initiated
126 using only a "target remote" or "target extended-remote" command
127 (no "set sysroot" or "file" commands are required). See "New remote
130 * The "dump" command now supports verilog hex format.
132 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
134 * On GNU/Linux, GDB and gdbserver are now able to access executable
135 and shared library files without a "set sysroot" command when
136 attaching to processes running in different mount namespaces from
137 the debugger. This makes it possible to attach to processes in
138 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
139 See "New remote packets" below.
141 * The "tui reg" command now provides completion for all of the
142 available register groups, including target specific groups.
144 * The HISTSIZE environment variable is no longer read when determining
145 the size of GDB's command history. GDB now instead reads the dedicated
146 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
147 disables truncation of command history. Non-numeric values of GDBHISTSIZE
152 ** Memory ports can now be unbuffered.
156 ** gdb.Objfile objects have a new attribute "username",
157 which is the name of the objfile as specified by the user,
158 without, for example, resolving symlinks.
159 ** You can now write frame unwinders in Python.
160 ** gdb.Type objects have a new method "optimized_out",
161 returning optimized out gdb.Value instance of this type.
162 ** gdb.Value objects have new methods "reference_value" and
163 "const_value" which return a reference to the value and a
164 "const" version of the value respectively.
168 maint print symbol-cache
169 Print the contents of the symbol cache.
171 maint print symbol-cache-statistics
172 Print statistics of symbol cache usage.
174 maint flush-symbol-cache
175 Flush the contents of the symbol cache.
179 Start branch trace recording using Branch Trace Store (BTS) format.
182 Evaluate expression by using the compiler and print result.
186 Explicit commands for enabling and disabling tui mode.
189 set mpx bound on i386 and amd64
190 Support for bound table investigation on Intel(R) MPX enabled applications.
194 Start branch trace recording using Intel(R) Processor Trace format.
197 Print information about branch tracing internals.
199 maint btrace packet-history
200 Print the raw branch tracing data.
202 maint btrace clear-packet-history
203 Discard the stored raw branch tracing data.
206 Discard all branch tracing data. It will be fetched and processed
207 anew by the next "record" command.
212 Renamed from "set debug dwarf2-die".
214 Renamed from "show debug dwarf2-die".
217 Renamed from "set debug dwarf2-read".
218 show debug dwarf-read
219 Renamed from "show debug dwarf2-read".
221 maint set dwarf always-disassemble
222 Renamed from "maint set dwarf2 always-disassemble".
223 maint show dwarf always-disassemble
224 Renamed from "maint show dwarf2 always-disassemble".
226 maint set dwarf max-cache-age
227 Renamed from "maint set dwarf2 max-cache-age".
228 maint show dwarf max-cache-age
229 Renamed from "maint show dwarf2 max-cache-age".
232 show debug dwarf-line
233 Control display of debugging info regarding DWARF line processing.
237 Set the maximum number of candidates to be considered during
238 completion. The default value is 200. This limit allows GDB
239 to avoid generating large completion lists, the computation of
240 which can cause the debugger to become temporarily unresponsive.
242 set history remove-duplicates
243 show history remove-duplicates
244 Control the removal of duplicate history entries.
246 maint set symbol-cache-size
247 maint show symbol-cache-size
248 Control the size of the symbol cache.
250 set|show record btrace bts buffer-size
251 Set and show the size of the ring buffer used for branch tracing in
253 The obtained size may differ from the requested size. Use "info
254 record" to see the obtained buffer size.
256 set debug linux-namespaces
257 show debug linux-namespaces
258 Control display of debugging info regarding Linux namespaces.
260 set|show record btrace pt buffer-size
261 Set and show the size of the ring buffer used for branch tracing in
262 Intel(R) Processor Trace format.
263 The obtained size may differ from the requested size. Use "info
264 record" to see the obtained buffer size.
266 maint set|show btrace pt skip-pad
267 Set and show whether PAD packets are skipped when computing the
270 * The command 'thread apply all' can now support new option '-ascending'
271 to call its specified command for all threads in ascending order.
273 * Python/Guile scripting
275 ** GDB now supports auto-loading of Python/Guile scripts contained in the
276 special section named `.debug_gdb_scripts'.
280 qXfer:btrace-conf:read
281 Return the branch trace configuration for the current thread.
283 Qbtrace-conf:bts:size
284 Set the requested ring buffer size for branch tracing in BTS format.
287 Enable Intel(R) Procesor Trace-based branch tracing for the current
288 process. The remote stub reports support for this packet to GDB's
292 Set the requested ring buffer size for branch tracing in Intel(R) Processor
296 Indicates a memory breakpoint instruction was executed, irrespective
297 of whether it was GDB that planted the breakpoint or the breakpoint
298 is hardcoded in the program. This is required for correct non-stop
302 Indicates the target stopped for a hardware breakpoint. This is
303 required for correct non-stop mode operation.
306 Return information about files on the remote system.
309 Return the full absolute name of the file that was executed to
310 create a process running on the remote system.
313 Select the filesystem on which vFile: operations with filename
314 arguments will operate. This is required for GDB to be able to
315 access files on remote targets where the remote stub does not
316 share a common filesystem with the inferior(s).
319 Indicates that a fork system call was executed.
322 Indicates that a vfork system call was executed.
324 vforkdone stop reason
325 Indicates that a vfork child of the specified process has executed
326 an exec or exit, allowing the vfork parent to resume execution.
328 fork-events and vfork-events features in qSupported
329 The qSupported packet allows GDB to request support for fork and
330 vfork events using new 'gdbfeatures' fork-events and vfork-events,
331 and the qSupported response can contain the corresponding
332 'stubfeatures'. Set and show commands can be used to display
333 whether these features are enabled.
335 * Extended-remote fork events
337 ** GDB now has support for fork events on extended-remote Linux
338 targets. For targets with Linux kernels 2.5.60 and later, this
339 enables follow-fork-mode and detach-on-fork for both fork and
340 vfork, as well as fork and vfork catchpoints.
342 * The info record command now shows the recording format and the
343 branch tracing configuration for the current thread when using
344 the btrace record target.
345 For the BTS format, it shows the ring buffer size.
347 * GDB now has support for DTrace USDT (Userland Static Defined
348 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
350 * GDB now supports access to vector registers on S/390 GNU/Linux
353 * Removed command line options
355 -xdb HP-UX XDB compatibility mode.
357 * Removed targets and native configurations
359 HP/PA running HP-UX hppa*-*-hpux*
360 Itanium running HP-UX ia64-*-hpux*
362 * New configure options
365 This configure option allows the user to build GDB with support for
366 Intel(R) Processor Trace (default: auto). This requires libipt.
368 --with-libipt-prefix=PATH
369 Specify the path to the version of libipt that GDB should use.
370 $PATH/include should contain the intel-pt.h header and
371 $PATH/lib should contain the libipt.so library.
373 *** Changes in GDB 7.9.1
377 ** Xmethods can now specify a result type.
379 *** Changes in GDB 7.9
381 * GDB now supports hardware watchpoints on x86 GNU Hurd.
385 ** You can now access frame registers from Python scripts.
386 ** New attribute 'producer' for gdb.Symtab objects.
387 ** gdb.Objfile objects have a new attribute "progspace",
388 which is the gdb.Progspace object of the containing program space.
389 ** gdb.Objfile objects have a new attribute "owner".
390 ** gdb.Objfile objects have a new attribute "build_id",
391 which is the build ID generated when the file was built.
392 ** gdb.Objfile objects have a new method "add_separate_debug_file".
393 ** A new event "gdb.clear_objfiles" has been added, triggered when
394 selecting a new file to debug.
395 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
396 ** New function gdb.lookup_objfile.
398 New events which are triggered when GDB modifies the state of the
401 ** gdb.events.inferior_call_pre: Function call is about to be made.
402 ** gdb.events.inferior_call_post: Function call has just been made.
403 ** gdb.events.memory_changed: A memory location has been altered.
404 ** gdb.events.register_changed: A register has been altered.
406 * New Python-based convenience functions:
408 ** $_caller_is(name [, number_of_frames])
409 ** $_caller_matches(regexp [, number_of_frames])
410 ** $_any_caller_is(name [, number_of_frames])
411 ** $_any_caller_matches(regexp [, number_of_frames])
413 * GDB now supports the compilation and injection of source code into
414 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
415 to compile the source code to object code, and if successful, inject
416 and execute that code within the current context of the inferior.
417 Currently the C language is supported. The commands used to
418 interface with this new feature are:
420 compile code [-raw|-r] [--] [source code]
421 compile file [-raw|-r] filename
425 demangle [-l language] [--] name
426 Demangle "name" in the specified language, or the current language
427 if elided. This command is renamed from the "maint demangle" command.
428 The latter is kept as a no-op to avoid "maint demangle" being interpreted
429 as "maint demangler-warning".
431 queue-signal signal-name-or-number
432 Queue a signal to be delivered to the thread when it is resumed.
434 add-auto-load-scripts-directory directory
435 Add entries to the list of directories from which to load auto-loaded
438 maint print user-registers
439 List all currently available "user" registers.
441 compile code [-r|-raw] [--] [source code]
442 Compile, inject, and execute in the inferior the executable object
443 code produced by compiling the provided source code.
445 compile file [-r|-raw] filename
446 Compile and inject into the inferior the executable object code
447 produced by compiling the source code stored in the filename
450 * On resume, GDB now always passes the signal the program had stopped
451 for to the thread the signal was sent to, even if the user changed
452 threads before resuming. Previously GDB would often (but not
453 always) deliver the signal to the thread that happens to be current
456 * Conversely, the "signal" command now consistently delivers the
457 requested signal to the current thread. GDB now asks for
458 confirmation if the program had stopped for a signal and the user
459 switched threads meanwhile.
461 * "breakpoint always-inserted" modes "off" and "auto" merged.
463 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
464 won't remove breakpoints from the target until all threads stop,
465 even in non-stop mode. The "auto" mode has been removed, and "off"
466 is now the default mode.
470 set debug symbol-lookup
471 show debug symbol-lookup
472 Control display of debugging info regarding symbol lookup.
476 ** The -list-thread-groups command outputs an exit-code field for
477 inferiors that have exited.
481 MIPS SDE mips*-sde*-elf*
485 Support for these obsolete configurations has been removed.
487 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
488 SGI Irix-5.x mips-*-irix5*
489 SGI Irix-6.x mips-*-irix6*
490 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
491 VAX running Ultrix vax-*-ultrix*
493 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
494 and "assf"), have been removed. Use the "sharedlibrary" command, or
495 its alias "share", instead.
497 *** Changes in GDB 7.8
499 * New command line options
502 This is an alias for the --data-directory option.
504 * GDB supports printing and modifying of variable length automatic arrays
505 as specified in ISO C99.
507 * The ARM simulator now supports instruction level tracing
508 with or without disassembly.
512 GDB now has support for scripting using Guile. Whether this is
513 available is determined at configure time.
514 Guile version 2.0 or greater is required.
515 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
517 * New commands (for set/show, see "New options" below)
521 Invoke CODE by passing it to the Guile interpreter.
525 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
527 info auto-load guile-scripts [regexp]
528 Print the list of automatically loaded Guile scripts.
530 * The source command is now capable of sourcing Guile scripts.
531 This feature is dependent on the debugger being built with Guile support.
535 set print symbol-loading (off|brief|full)
536 show print symbol-loading
537 Control whether to print informational messages when loading symbol
538 information for a file. The default is "full", but when debugging
539 programs with large numbers of shared libraries the amount of output
542 set guile print-stack (none|message|full)
543 show guile print-stack
544 Show a stack trace when an error is encountered in a Guile script.
546 set auto-load guile-scripts (on|off)
547 show auto-load guile-scripts
548 Control auto-loading of Guile script files.
550 maint ada set ignore-descriptive-types (on|off)
551 maint ada show ignore-descriptive-types
552 Control whether the debugger should ignore descriptive types in Ada
553 programs. The default is not to ignore the descriptive types. See
554 the user manual for more details on descriptive types and the intended
555 usage of this option.
557 set auto-connect-native-target
559 Control whether GDB is allowed to automatically connect to the
560 native target for the run, attach, etc. commands when not connected
561 to any target yet. See also "target native" below.
563 set record btrace replay-memory-access (read-only|read-write)
564 show record btrace replay-memory-access
565 Control what memory accesses are allowed during replay.
567 maint set target-async (on|off)
568 maint show target-async
569 This controls whether GDB targets operate in synchronous or
570 asynchronous mode. Normally the default is asynchronous, if it is
571 available; but this can be changed to more easily debug problems
572 occurring only in synchronous mode.
574 set mi-async (on|off)
576 Control whether MI asynchronous mode is preferred. This supersedes
577 "set target-async" of previous GDB versions.
579 * "set target-async" is deprecated as a CLI option and is now an alias
580 for "set mi-async" (only puts MI into async mode).
582 * Background execution commands (e.g., "c&", "s&", etc.) are now
583 possible ``out of the box'' if the target supports them. Previously
584 the user would need to explicitly enable the possibility with the
585 "set target-async on" command.
587 * New features in the GDB remote stub, GDBserver
589 ** New option --debug-format=option1[,option2,...] allows one to add
590 additional text to each output. At present only timestamps
591 are supported: --debug-format=timestamps.
592 Timestamps can also be turned on with the
593 "monitor set debug-format timestamps" command from GDB.
595 * The 'record instruction-history' command now starts counting instructions
596 at one. This also affects the instruction ranges reported by the
597 'record function-call-history' command when given the /i modifier.
599 * The command 'record function-call-history' supports a new modifier '/c' to
600 indent the function names based on their call stack depth.
601 The fields for the '/i' and '/l' modifier have been reordered.
602 The source line range is now prefixed with 'at'.
603 The instruction range is now prefixed with 'inst'.
604 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
605 "record instruction-history" and "list" commands.
607 * The ranges given as arguments to the 'record function-call-history' and
608 'record instruction-history' commands are now inclusive.
610 * The btrace record target now supports the 'record goto' command.
611 For locations inside the execution trace, the back trace is computed
612 based on the information stored in the execution trace.
614 * The btrace record target supports limited reverse execution and replay.
615 The target does not record data and therefore does not allow reading
618 * The "catch syscall" command now works on s390*-linux* targets.
620 * The "compare-sections" command is no longer specific to target
621 remote. It now works with all targets.
623 * All native targets are now consistently called "native".
624 Consequently, the "target child", "target GNU", "target djgpp",
625 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
626 commands have been replaced with "target native". The QNX/NTO port
627 leaves the "procfs" target in place and adds a "native" target for
628 consistency with other ports. The impact on users should be minimal
629 as these commands previously either throwed an error, or were
630 no-ops. The target's name is visible in the output of the following
631 commands: "help target", "info target", "info files", "maint print
634 * The "target native" command now connects to the native target. This
635 can be used to launch native programs even when "set
636 auto-connect-native-target" is set to off.
638 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
640 * Support for Intel(R) AVX-512 registers on GNU/Linux.
641 Support displaying and modifying Intel(R) AVX-512 registers
642 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
646 qXfer:btrace:read's annex
647 The qXfer:btrace:read packet supports a new annex 'delta' to read
648 branch trace incrementally.
652 ** Valid Python operations on gdb.Value objects representing
653 structs/classes invoke the corresponding overloaded operators if
655 ** New `Xmethods' feature in the Python API. Xmethods are
656 additional methods or replacements for existing methods of a C++
657 class. This feature is useful for those cases where a method
658 defined in C++ source code could be inlined or optimized out by
659 the compiler, making it unavailable to GDB.
662 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
664 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
665 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
666 its alias "share", instead.
668 * The commands "set remotebaud" and "show remotebaud" are no longer
669 supported. Use "set serial baud" and "show serial baud" (respectively)
674 ** A new option "-gdb-set mi-async" replaces "-gdb-set
675 target-async". The latter is left as a deprecated alias of the
676 former for backward compatibility. If the target supports it,
677 CLI background execution commands are now always possible by
678 default, independently of whether the frontend stated a
679 preference for asynchronous execution with "-gdb-set mi-async".
680 Previously "-gdb-set target-async off" affected both MI execution
681 commands and CLI execution commands.
683 *** Changes in GDB 7.7
685 * Improved support for process record-replay and reverse debugging on
686 arm*-linux* targets. Support for thumb32 and syscall instruction
687 recording has been added.
689 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
691 * GDB now supports Fission DWP file format version 2.
692 http://gcc.gnu.org/wiki/DebugFission
694 * New convenience function "$_isvoid", to check whether an expression
695 is void. A void expression is an expression where the type of the
696 result is "void". For example, some convenience variables may be
697 "void" when evaluated (e.g., "$_exitcode" before the execution of
698 the program being debugged; or an undefined convenience variable).
699 Another example, when calling a function whose return type is
702 * The "maintenance print objfiles" command now takes an optional regexp.
704 * The "catch syscall" command now works on arm*-linux* targets.
706 * GDB now consistently shows "<not saved>" when printing values of
707 registers the debug info indicates have not been saved in the frame
708 and there's nowhere to retrieve them from
709 (callee-saved/call-clobbered registers):
714 (gdb) info registers rax
717 Before, the former would print "<optimized out>", and the latter
718 "*value not available*".
720 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
725 ** Frame filters and frame decorators have been added.
726 ** Temporary breakpoints are now supported.
727 ** Line tables representation has been added.
728 ** New attribute 'parent_type' for gdb.Field objects.
729 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
730 ** New attribute 'name' for gdb.Type objects.
734 Nios II ELF nios2*-*-elf
735 Nios II GNU/Linux nios2*-*-linux
736 Texas Instruments MSP430 msp430*-*-elf
738 * Removed native configurations
740 Support for these a.out NetBSD and OpenBSD obsolete configurations has
741 been removed. ELF variants of these configurations are kept supported.
743 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
744 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
745 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
746 i[34567]86-*-openbsd3.[0-3]
747 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
748 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
749 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
753 Like "catch throw", but catches a re-thrown exception.
755 Renamed from old "maint check-symtabs".
757 Perform consistency checks on symtabs.
759 Expand symtabs matching an optional regexp.
762 Display the details of GDB configure-time options.
764 maint set|show per-command
765 maint set|show per-command space
766 maint set|show per-command time
767 maint set|show per-command symtab
768 Enable display of per-command gdb resource usage.
770 remove-symbol-file FILENAME
771 remove-symbol-file -a ADDRESS
772 Remove a symbol file added via add-symbol-file. The file to remove
773 can be identified by its filename or by an address that lies within
774 the boundaries of this symbol file in memory.
777 info exceptions REGEXP
778 Display the list of Ada exceptions defined in the program being
779 debugged. If provided, only the exceptions whose names match REGEXP
784 set debug symfile off|on
786 Control display of debugging info regarding reading symbol files and
787 symbol tables within those files
789 set print raw frame-arguments
790 show print raw frame-arguments
791 Set/show whether to print frame arguments in raw mode,
792 disregarding any defined pretty-printers.
794 set remote trace-status-packet
795 show remote trace-status-packet
796 Set/show the use of remote protocol qTStatus packet.
800 Control display of debugging messages related to Nios II targets.
804 Control whether target-assisted range stepping is enabled.
806 set startup-with-shell
807 show startup-with-shell
808 Specifies whether Unix child processes are started via a shell or
813 Use the target memory cache for accesses to the code segment. This
814 improves performance of remote debugging (particularly disassembly).
816 * You can now use a literal value 'unlimited' for options that
817 interpret 0 or -1 as meaning "unlimited". E.g., "set
818 trace-buffer-size unlimited" is now an alias for "set
819 trace-buffer-size -1" and "set height unlimited" is now an alias for
822 * The "set debug symtab-create" debugging option of GDB has been changed to
823 accept a verbosity level. 0 means "off", 1 provides basic debugging
824 output, and values of 2 or greater provides more verbose output.
826 * New command-line options
828 Display the details of GDB configure-time options.
830 * The command 'tsave' can now support new option '-ctf' to save trace
831 buffer in Common Trace Format.
833 * Newly installed $prefix/bin/gcore acts as a shell interface for the
836 * GDB now implements the the C++ 'typeid' operator.
838 * The new convenience variable $_exception holds the exception being
839 thrown or caught at an exception-related catchpoint.
841 * The exception-related catchpoints, like "catch throw", now accept a
842 regular expression which can be used to filter exceptions by type.
844 * The new convenience variable $_exitsignal is automatically set to
845 the terminating signal number when the program being debugged dies
846 due to an uncaught signal.
850 ** All MI commands now accept an optional "--language" option.
851 Support for this feature can be verified by using the "-list-features"
852 command, which should contain "language-option".
854 ** The new command -info-gdb-mi-command allows the user to determine
855 whether a GDB/MI command is supported or not.
857 ** The "^error" result record returned when trying to execute an undefined
858 GDB/MI command now provides a variable named "code" whose content is the
859 "undefined-command" error code. Support for this feature can be verified
860 by using the "-list-features" command, which should contain
861 "undefined-command-error-code".
863 ** The -trace-save MI command can optionally save trace buffer in Common
866 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
868 ** The command -data-list-register-values now accepts an optional
869 "--skip-unavailable" option. When used, only the available registers
872 ** The new command -trace-frame-collected dumps collected variables,
873 computed expressions, tvars, memory and registers in a traceframe.
875 ** The commands -stack-list-locals, -stack-list-arguments and
876 -stack-list-variables now accept an option "--skip-unavailable".
877 When used, only the available locals or arguments are displayed.
879 ** The -exec-run command now accepts an optional "--start" option.
880 When used, the command follows the same semantics as the "start"
881 command, stopping the program's execution at the start of its
882 main subprogram. Support for this feature can be verified using
883 the "-list-features" command, which should contain
884 "exec-run-start-option".
886 ** The new commands -catch-assert and -catch-exceptions insert
887 catchpoints stopping the program when Ada exceptions are raised.
889 ** The new command -info-ada-exceptions provides the equivalent of
890 the new "info exceptions" command.
892 * New system-wide configuration scripts
893 A GDB installation now provides scripts suitable for use as system-wide
894 configuration scripts for the following systems:
898 * GDB now supports target-assigned range stepping with remote targets.
899 This improves the performance of stepping source lines by reducing
900 the number of control packets from/to GDB. See "New remote packets"
903 * GDB now understands the element 'tvar' in the XML traceframe info.
904 It has the id of the collected trace state variables.
906 * On S/390 targets that provide the transactional-execution feature,
907 the program interruption transaction diagnostic block (TDB) is now
908 represented as a number of additional "registers" in GDB.
914 The vCont packet supports a new 'r' action, that tells the remote
915 stub to step through an address range itself, without GDB
916 involvemement at each single-step.
918 qXfer:libraries-svr4:read's annex
919 The previously unused annex of the qXfer:libraries-svr4:read packet
920 is now used to support passing an argument list. The remote stub
921 reports support for this argument list to GDB's qSupported query.
922 The defined arguments are "start" and "prev", used to reduce work
923 necessary for library list updating, resulting in significant
926 * New features in the GDB remote stub, GDBserver
928 ** GDBserver now supports target-assisted range stepping. Currently
929 enabled on x86/x86_64 GNU/Linux targets.
931 ** GDBserver now adds element 'tvar' in the XML in the reply to
932 'qXfer:traceframe-info:read'. It has the id of the collected
933 trace state variables.
935 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
938 * New 'z' formatter for printing and examining memory, this displays the
939 value as hexadecimal zero padded on the left to the size of the type.
941 * GDB can now use Windows x64 unwinding data.
943 * The "set remotebaud" command has been replaced by "set serial baud".
944 Similarly, "show remotebaud" has been replaced by "show serial baud".
945 The "set remotebaud" and "show remotebaud" commands are still available
946 to provide backward compatibility with older versions of GDB.
948 *** Changes in GDB 7.6
950 * Target record has been renamed to record-full.
951 Record/replay is now enabled with the "record full" command.
952 This also affects settings that are associated with full record/replay
953 that have been moved from "set/show record" to "set/show record full":
955 set|show record full insn-number-max
956 set|show record full stop-at-limit
957 set|show record full memory-query
959 * A new record target "record-btrace" has been added. The new target
960 uses hardware support to record the control-flow of a process. It
961 does not support replaying the execution, but it implements the
962 below new commands for investigating the recorded execution log.
963 This new recording method can be enabled using:
967 The "record-btrace" target is only available on Intel Atom processors
968 and requires a Linux kernel 2.6.32 or later.
970 * Two new commands have been added for record/replay to give information
971 about the recorded execution without having to replay the execution.
972 The commands are only supported by "record btrace".
974 record instruction-history prints the execution history at
975 instruction granularity
977 record function-call-history prints the execution history at
980 * New native configurations
982 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
983 FreeBSD/powerpc powerpc*-*-freebsd
984 x86_64/Cygwin x86_64-*-cygwin*
985 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
989 ARM AArch64 aarch64*-*-elf
990 ARM AArch64 GNU/Linux aarch64*-*-linux
991 Lynx 178 PowerPC powerpc-*-lynx*178
992 x86_64/Cygwin x86_64-*-cygwin*
993 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
995 * If the configured location of system.gdbinit file (as given by the
996 --with-system-gdbinit option at configure time) is in the
997 data-directory (as specified by --with-gdb-datadir at configure
998 time) or in one of its subdirectories, then GDB will look for the
999 system-wide init file in the directory specified by the
1000 --data-directory command-line option.
1002 * New command line options:
1004 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1005 other initialization files, unlike -nx which disables all of them.
1007 * Removed command line options
1009 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1012 * The 'ptype' and 'whatis' commands now accept an argument to control
1015 * 'info proc' now works on some core files.
1019 ** Vectors can be created with gdb.Type.vector.
1021 ** Python's atexit.register now works in GDB.
1023 ** Types can be pretty-printed via a Python API.
1025 ** Python 3 is now supported (in addition to Python 2.4 or later)
1027 ** New class gdb.Architecture exposes GDB's internal representation
1028 of architecture in the Python API.
1030 ** New method Frame.architecture returns the gdb.Architecture object
1031 corresponding to the frame's architecture.
1033 * New Python-based convenience functions:
1035 ** $_memeq(buf1, buf2, length)
1036 ** $_streq(str1, str2)
1038 ** $_regex(str, regex)
1040 * The 'cd' command now defaults to using '~' (the home directory) if not
1043 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1044 default for GCC since November 2000.
1046 * The command 'forward-search' can now be abbreviated as 'fo'.
1048 * The command 'info tracepoints' can now display 'installed on target'
1049 or 'not installed on target' for each non-pending location of tracepoint.
1051 * New configure options
1053 --enable-libmcheck/--disable-libmcheck
1054 By default, development versions are built with -lmcheck on hosts
1055 that support it, in order to help track memory corruption issues.
1056 Release versions, on the other hand, are built without -lmcheck
1057 by default. The --enable-libmcheck/--disable-libmcheck configure
1058 options allow the user to override that default.
1059 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1060 This configure option allows the user to build GDB with
1061 libbabeltrace using which GDB can read Common Trace Format data.
1063 * New commands (for set/show, see "New options" below)
1066 Catch signals. This is similar to "handle", but allows commands and
1067 conditions to be attached.
1070 List the BFDs known to GDB.
1072 python-interactive [command]
1074 Start a Python interactive prompt, or evaluate the optional command
1075 and print the result of expressions.
1078 "py" is a new alias for "python".
1080 enable type-printer [name]...
1081 disable type-printer [name]...
1082 Enable or disable type printers.
1086 ** For the Renesas Super-H architecture, the "regs" command has been removed
1087 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1092 set print type methods (on|off)
1093 show print type methods
1094 Control whether method declarations are displayed by "ptype".
1095 The default is to show them.
1097 set print type typedefs (on|off)
1098 show print type typedefs
1099 Control whether typedef definitions are displayed by "ptype".
1100 The default is to show them.
1102 set filename-display basename|relative|absolute
1103 show filename-display
1104 Control the way in which filenames is displayed.
1105 The default is "relative", which preserves previous behavior.
1107 set trace-buffer-size
1108 show trace-buffer-size
1109 Request target to change the size of trace buffer.
1111 set remote trace-buffer-size-packet auto|on|off
1112 show remote trace-buffer-size-packet
1113 Control the use of the remote protocol `QTBuffer:size' packet.
1117 Control display of debugging messages related to ARM AArch64.
1120 set debug coff-pe-read
1121 show debug coff-pe-read
1122 Control display of debugging messages related to reading of COFF/PE
1127 Control display of debugging messages related to Mach-O symbols
1130 set debug notification
1131 show debug notification
1132 Control display of debugging info for async remote notification.
1136 ** Command parameter changes are now notified using new async record
1137 "=cmd-param-changed".
1138 ** Trace frame changes caused by command "tfind" are now notified using
1139 new async record "=traceframe-changed".
1140 ** The creation, deletion and modification of trace state variables
1141 are now notified using new async records "=tsv-created",
1142 "=tsv-deleted" and "=tsv-modified".
1143 ** The start and stop of process record are now notified using new
1144 async record "=record-started" and "=record-stopped".
1145 ** Memory changes are now notified using new async record
1147 ** The data-disassemble command response will include a "fullname" field
1148 containing the absolute file name when source has been requested.
1149 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1150 command, to allow pattern filling of memory areas.
1151 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1152 library load/unload events.
1153 ** The response to breakpoint commands and breakpoint async records
1154 includes an "installed" field containing a boolean state about each
1155 non-pending tracepoint location is whether installed on target or not.
1156 ** Output of the "-trace-status" command includes a "trace-file" field
1157 containing the name of the trace file being examined. This field is
1158 optional, and only present when examining a trace file.
1159 ** The "fullname" field is now always present along with the "file" field,
1160 even if the file cannot be found by GDB.
1162 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1163 You must have the LZMA library available when configuring GDB for this
1164 feature to be enabled. For more information, see:
1165 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1167 * New remote packets
1170 Set the size of trace buffer. The remote stub reports support for this
1171 packet to gdb's qSupported query.
1174 Enable Branch Trace Store (BTS)-based branch tracing for the current
1175 thread. The remote stub reports support for this packet to gdb's
1179 Disable branch tracing for the current thread. The remote stub reports
1180 support for this packet to gdb's qSupported query.
1183 Read the traced branches for the current thread. The remote stub
1184 reports support for this packet to gdb's qSupported query.
1186 *** Changes in GDB 7.5
1188 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1189 for more x32 ABI info.
1191 * GDB now supports access to MIPS DSP registers on Linux targets.
1193 * GDB now supports debugging microMIPS binaries.
1195 * The "info os" command on GNU/Linux can now display information on
1196 several new classes of objects managed by the operating system:
1197 "info os procgroups" lists process groups
1198 "info os files" lists file descriptors
1199 "info os sockets" lists internet-domain sockets
1200 "info os shm" lists shared-memory regions
1201 "info os semaphores" lists semaphores
1202 "info os msg" lists message queues
1203 "info os modules" lists loaded kernel modules
1205 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1206 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1207 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1208 options and inspect the probe arguments using the new $_probe_arg family
1209 of convenience variables. You can obtain more information about SystemTap
1210 in <http://sourceware.org/systemtap/>.
1212 * GDB now supports reversible debugging on ARM, it allows you to
1213 debug basic ARM and THUMB instructions, and provides
1214 record/replay support.
1216 * The option "symbol-reloading" has been deleted as it is no longer used.
1220 ** GDB commands implemented in Python can now be put in command class
1223 ** The "maint set python print-stack on|off" is now deleted.
1225 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1226 apply "flag enum"-style pretty-printing to any enum.
1228 ** gdb.lookup_symbol can now work when there is no current frame.
1230 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1231 the source at which the symbol was defined.
1233 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1234 method 'value'. The former indicates whether the symbol needs a
1235 frame in order to compute its value, and the latter computes the
1238 ** A new method 'referenced_value' on gdb.Value objects which can
1239 dereference pointer as well as C++ reference values.
1241 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1242 which return the global and static blocks (as gdb.Block objects),
1243 of the underlying symbol table, respectively.
1245 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1246 object associated with a PC value.
1248 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1249 of the address range occupied by code for the current source line.
1251 * Go language support.
1252 GDB now supports debugging programs written in the Go programming
1255 * GDBserver now supports stdio connections.
1256 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1258 * The binary "gdbtui" can no longer be built or installed.
1259 Use "gdb -tui" instead.
1261 * GDB will now print "flag" enums specially. A flag enum is one where
1262 all the enumerator values have no bits in common when pairwise
1263 "and"ed. When printing a value whose type is a flag enum, GDB will
1264 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1265 (gdb) print (enum E) 3
1268 * The filename part of a linespec will now match trailing components
1269 of a source file name. For example, "break gcc/expr.c:1000" will
1270 now set a breakpoint in build/gcc/expr.c, but not
1271 build/libcpp/expr.c.
1273 * The "info proc" and "generate-core-file" commands will now also
1274 work on remote targets connected to GDBserver on Linux.
1276 * The command "info catch" has been removed. It has been disabled
1277 since December 2007.
1279 * The "catch exception" and "catch assert" commands now accept
1280 a condition at the end of the command, much like the "break"
1281 command does. For instance:
1283 (gdb) catch exception Constraint_Error if Barrier = True
1285 Previously, it was possible to add a condition to such catchpoints,
1286 but it had to be done as a second step, after the catchpoint had been
1287 created, using the "condition" command.
1289 * The "info static-tracepoint-marker" command will now also work on
1290 native Linux targets with in-process agent.
1292 * GDB can now set breakpoints on inlined functions.
1294 * The .gdb_index section has been updated to include symbols for
1295 inlined functions. GDB will ignore older .gdb_index sections by
1296 default, which could cause symbol files to be loaded more slowly
1297 until their .gdb_index sections can be recreated. The new command
1298 "set use-deprecated-index-sections on" will cause GDB to use any older
1299 .gdb_index sections it finds. This will restore performance, but the
1300 ability to set breakpoints on inlined functions will be lost in symbol
1301 files with older .gdb_index sections.
1303 The .gdb_index section has also been updated to record more information
1304 about each symbol. This speeds up the "info variables", "info functions"
1305 and "info types" commands when used with programs having the .gdb_index
1306 section, as well as speeding up debugging with shared libraries using
1307 the .gdb_index section.
1309 * Ada support for GDB/MI Variable Objects has been added.
1311 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1316 ** New command -info-os is the MI equivalent of "info os".
1318 ** Output logs ("set logging" and related) now include MI output.
1322 ** "set use-deprecated-index-sections on|off"
1323 "show use-deprecated-index-sections on|off"
1324 Controls the use of deprecated .gdb_index sections.
1326 ** "catch load" and "catch unload" can be used to stop when a shared
1327 library is loaded or unloaded, respectively.
1329 ** "enable count" can be used to auto-disable a breakpoint after
1332 ** "info vtbl" can be used to show the virtual method tables for
1333 C++ and Java objects.
1335 ** "explore" and its sub commands "explore value" and "explore type"
1336 can be used to recursively explore values and types of
1337 expressions. These commands are available only if GDB is
1338 configured with '--with-python'.
1340 ** "info auto-load" shows status of all kinds of auto-loaded files,
1341 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1342 sequences of commands files, "info auto-load python-scripts"
1343 shows status of auto-loading Python script files,
1344 "info auto-load local-gdbinit" shows status of loading init file
1345 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1346 status of inferior specific thread debugging shared library loading.
1348 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1349 and "show auto-load-scripts" commands have been deprecated, use their
1350 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1351 and "show auto-load python-scripts" counterparts instead.
1353 ** "dprintf location,format,args..." creates a dynamic printf, which
1354 is basically a breakpoint that does a printf and immediately
1355 resumes your program's execution, so it is like a printf that you
1356 can insert dynamically at runtime instead of at compiletime.
1358 ** "set print symbol"
1360 Controls whether GDB attempts to display the symbol, if any,
1361 corresponding to addresses it prints. This defaults to "on", but
1362 you can set it to "off" to restore GDB's previous behavior.
1364 * Deprecated commands
1366 ** For the Renesas Super-H architecture, the "regs" command has been
1367 deprecated, and "info all-registers" should be used instead.
1371 Renesas RL78 rl78-*-elf
1372 HP OpenVMS ia64 ia64-hp-openvms*
1374 * GDBserver supports evaluation of breakpoint conditions. When
1375 support is advertised by GDBserver, GDB may be told to send the
1376 breakpoint conditions in bytecode form to GDBserver. GDBserver
1377 will only report the breakpoint trigger to GDB when its condition
1382 set mips compression
1383 show mips compression
1384 Select the compressed ISA encoding used in functions that have no symbol
1385 information available. The encoding can be set to either of:
1388 and is updated automatically from ELF file flags if available.
1390 set breakpoint condition-evaluation
1391 show breakpoint condition-evaluation
1392 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1393 GDBserver ("target"). Default option "auto" chooses the most efficient
1395 This option can improve debugger efficiency depending on the speed of the
1399 Disable auto-loading globally.
1402 Show auto-loading setting of all kinds of auto-loaded files.
1404 set auto-load gdb-scripts on|off
1405 show auto-load gdb-scripts
1406 Control auto-loading of GDB canned sequences of commands files.
1408 set auto-load python-scripts on|off
1409 show auto-load python-scripts
1410 Control auto-loading of Python script files.
1412 set auto-load local-gdbinit on|off
1413 show auto-load local-gdbinit
1414 Control loading of init file (.gdbinit) from current directory.
1416 set auto-load libthread-db on|off
1417 show auto-load libthread-db
1418 Control auto-loading of inferior specific thread debugging shared library.
1420 set auto-load scripts-directory <dir1>[:<dir2>...]
1421 show auto-load scripts-directory
1422 Set a list of directories from which to load auto-loaded scripts.
1423 Automatically loaded Python scripts and GDB scripts are located in one
1424 of the directories listed by this option.
1425 The delimiter (':' above) may differ according to the host platform.
1427 set auto-load safe-path <dir1>[:<dir2>...]
1428 show auto-load safe-path
1429 Set a list of directories from which it is safe to auto-load files.
1430 The delimiter (':' above) may differ according to the host platform.
1432 set debug auto-load on|off
1433 show debug auto-load
1434 Control display of debugging info for auto-loading the files above.
1436 set dprintf-style gdb|call|agent
1438 Control the way in which a dynamic printf is performed; "gdb"
1439 requests a GDB printf command, while "call" causes dprintf to call a
1440 function in the inferior. "agent" requests that the target agent
1441 (such as GDBserver) do the printing.
1443 set dprintf-function <expr>
1444 show dprintf-function
1445 set dprintf-channel <expr>
1446 show dprintf-channel
1447 Set the function and optional first argument to the call when using
1448 the "call" style of dynamic printf.
1450 set disconnected-dprintf on|off
1451 show disconnected-dprintf
1452 Control whether agent-style dynamic printfs continue to be in effect
1453 after GDB disconnects.
1455 * New configure options
1457 --with-auto-load-dir
1458 Configure default value for the 'set auto-load scripts-directory'
1459 setting above. It defaults to '$debugdir:$datadir/auto-load',
1460 $debugdir representing global debugging info directories (available
1461 via 'show debug-file-directory') and $datadir representing GDB's data
1462 directory (available via 'show data-directory').
1464 --with-auto-load-safe-path
1465 Configure default value for the 'set auto-load safe-path' setting
1466 above. It defaults to the --with-auto-load-dir setting.
1468 --without-auto-load-safe-path
1469 Set 'set auto-load safe-path' to '/', effectively disabling this
1472 * New remote packets
1474 z0/z1 conditional breakpoints extension
1476 The z0/z1 breakpoint insertion packets have been extended to carry
1477 a list of conditional expressions over to the remote stub depending on the
1478 condition evaluation mode. The use of this extension can be controlled
1479 via the "set remote conditional-breakpoints-packet" command.
1483 Specify the signals which the remote stub may pass to the debugged
1484 program without GDB involvement.
1486 * New command line options
1488 --init-command=FILE, -ix Like --command, -x but execute it
1489 before loading inferior.
1490 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1491 execute it before loading inferior.
1493 *** Changes in GDB 7.4
1495 * GDB now handles ambiguous linespecs more consistently; the existing
1496 FILE:LINE support has been expanded to other types of linespecs. A
1497 breakpoint will now be set on all matching locations in all
1498 inferiors, and locations will be added or removed according to
1501 * GDB now allows you to skip uninteresting functions and files when
1502 stepping with the "skip function" and "skip file" commands.
1504 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1505 and "show remote hardware-watchpoint-length-limit". These allows to
1506 set or show the maximum length limit (in bytes) of a remote
1507 target hardware watchpoint.
1509 This allows e.g. to use "unlimited" hardware watchpoints with the
1510 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1511 watchpoints are slower than real hardware watchpoints but are
1512 significantly faster than gdb software watchpoints.
1516 ** The register_pretty_printer function in module gdb.printing now takes
1517 an optional `replace' argument. If True, the new printer replaces any
1520 ** The "maint set python print-stack on|off" command has been
1521 deprecated and will be deleted in GDB 7.5.
1522 A new command: "set python print-stack none|full|message" has
1523 replaced it. Additionally, the default for "print-stack" is
1524 now "message", which just prints the error message without
1527 ** A prompt substitution hook (prompt_hook) is now available to the
1530 ** A new Python module, gdb.prompt has been added to the GDB Python
1531 modules library. This module provides functionality for
1532 escape sequences in prompts (used by set/show
1533 extended-prompt). These escape sequences are replaced by their
1534 corresponding value.
1536 ** Python commands and convenience-functions located in
1537 'data-directory'/python/gdb/command and
1538 'data-directory'/python/gdb/function are now automatically loaded
1541 ** Blocks now provide four new attributes. global_block and
1542 static_block will return the global and static blocks
1543 respectively. is_static and is_global are boolean attributes
1544 that indicate if the block is one of those two types.
1546 ** Symbols now provide the "type" attribute, the type of the symbol.
1548 ** The "gdb.breakpoint" function has been deprecated in favor of
1551 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1552 of a function. This class is based on the "finish" command
1553 available in the CLI.
1555 ** Type objects for struct and union types now allow access to
1556 the fields using standard Python dictionary (mapping) methods.
1557 For example, "some_type['myfield']" now works, as does
1558 "some_type.items()".
1560 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1563 ** A new function, "deep_items" has been added to the gdb.types
1564 module in the GDB Python modules library. This function returns
1565 an iterator over the fields of a struct or union type. Unlike
1566 the standard Python "iteritems" method, it will recursively traverse
1567 any anonymous fields.
1571 ** "*stopped" events can report several new "reason"s, such as
1574 ** Breakpoint changes are now notified using new async records, like
1575 "=breakpoint-modified".
1577 ** New command -ada-task-info.
1579 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1580 $sdir specifies the default system locations of shared libraries.
1581 $pdir specifies the directory where the libpthread used by the application
1584 GDB no longer looks in $sdir and $pdir after it has searched the directories
1585 mentioned in libthread-db-search-path. If you want to search those
1586 directories, they must be specified in libthread-db-search-path.
1587 The default value of libthread-db-search-path on GNU/Linux and Solaris
1588 systems is now "$sdir:$pdir".
1590 $pdir is not supported by gdbserver, it is currently ignored.
1591 $sdir is supported by gdbserver.
1593 * New configure option --with-iconv-bin.
1594 When using the internationalization support like the one in the GNU C
1595 library, GDB will invoke the "iconv" program to get a list of supported
1596 character sets. If this program lives in a non-standard location, one can
1597 use this option to specify where to find it.
1599 * When natively debugging programs on PowerPC BookE processors running
1600 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1601 watchpoints, which specify a mask in addition to an address to watch.
1602 The mask specifies that some bits of an address (the bits which are
1603 reset in the mask) should be ignored when matching the address accessed
1604 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1605 section in the user manual for more details.
1607 * The new option --once causes GDBserver to stop listening for connections once
1608 the first connection is made. The listening port used by GDBserver will
1609 become available after that.
1611 * New commands "info macros" and "alias" have been added.
1613 * New function parameters suffix @entry specifies value of function parameter
1614 at the time the function got called. Entry values are available only since
1620 "!" is now an alias of the "shell" command.
1621 Note that no space is needed between "!" and SHELL COMMAND.
1625 watch EXPRESSION mask MASK_VALUE
1626 The watch command now supports the mask argument which allows creation
1627 of masked watchpoints, if the current architecture supports this feature.
1629 info auto-load-scripts [REGEXP]
1630 This command was formerly named "maintenance print section-scripts".
1631 It is now generally useful and is no longer a maintenance-only command.
1633 info macro [-all] [--] MACRO
1634 The info macro command has new options `-all' and `--'. The first for
1635 printing all definitions of a macro. The second for explicitly specifying
1636 the end of arguments and the beginning of the macro name in case the macro
1637 name starts with a hyphen.
1639 collect[/s] EXPRESSIONS
1640 The tracepoint collect command now takes an optional modifier "/s"
1641 that directs it to dereference pointer-to-character types and
1642 collect the bytes of memory up to a zero byte. The behavior is
1643 similar to what you see when you use the regular print command on a
1644 string. An optional integer following the "/s" sets a bound on the
1645 number of bytes that will be collected.
1648 The trace start command now interprets any supplied arguments as a
1649 note to be recorded with the trace run, with an effect similar to
1650 setting the variable trace-notes.
1653 The trace stop command now interprets any arguments as a note to be
1654 mentioned along with the tstatus report that the trace was stopped
1655 with a command. The effect is similar to setting the variable
1658 * Tracepoints can now be enabled and disabled at any time after a trace
1659 experiment has been started using the standard "enable" and "disable"
1660 commands. It is now possible to start a trace experiment with no enabled
1661 tracepoints; GDB will display a warning, but will allow the experiment to
1662 begin, assuming that tracepoints will be enabled as needed while the trace
1665 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1666 locations with 4-byte instructions, when they were previously
1667 limited to locations with instructions of 5 bytes or longer.
1671 set debug dwarf2-read
1672 show debug dwarf2-read
1673 Turns on or off display of debugging messages related to reading
1674 DWARF debug info. The default is off.
1676 set debug symtab-create
1677 show debug symtab-create
1678 Turns on or off display of debugging messages related to symbol table
1679 creation. The default is off.
1682 show extended-prompt
1683 Set the GDB prompt, and allow escape sequences to be inserted to
1684 display miscellaneous information (see 'help set extended-prompt'
1685 for the list of sequences). This prompt (and any information
1686 accessed through the escape sequences) is updated every time the
1687 prompt is displayed.
1689 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1690 show print entry-values
1691 Set printing of frame argument values at function entry. In some cases
1692 GDB can determine the value of function argument which was passed by the
1693 function caller, even if the value was modified inside the called function.
1695 set debug entry-values
1696 show debug entry-values
1697 Control display of debugging info for determining frame argument values at
1698 function entry and virtual tail call frames.
1700 set basenames-may-differ
1701 show basenames-may-differ
1702 Set whether a source file may have multiple base names.
1703 (A "base name" is the name of a file with the directory part removed.
1704 Example: The base name of "/home/user/hello.c" is "hello.c".)
1705 If set, GDB will canonicalize file names (e.g., expand symlinks)
1706 before comparing them. Canonicalization is an expensive operation,
1707 but it allows the same file be known by more than one base name.
1708 If not set (the default), all source files are assumed to have just
1709 one base name, and gdb will do file name comparisons more efficiently.
1715 Set a user name and notes for the current and any future trace runs.
1716 This is useful for long-running and/or disconnected traces, to
1717 inform others (or yourself) as to who is running the trace, supply
1718 contact information, or otherwise explain what is going on.
1720 set trace-stop-notes
1721 show trace-stop-notes
1722 Set a note attached to the trace run, that is displayed when the
1723 trace has been stopped by a tstop command. This is useful for
1724 instance as an explanation, if you are stopping a trace run that was
1725 started by someone else.
1727 * New remote packets
1731 Dynamically enable a tracepoint in a started trace experiment.
1735 Dynamically disable a tracepoint in a started trace experiment.
1739 Set the user and notes of the trace run.
1743 Query the current status of a tracepoint.
1747 Query the minimum length of instruction at which a fast tracepoint may
1750 * Dcache size (number of lines) and line-size are now runtime-configurable
1751 via "set dcache line" and "set dcache line-size" commands.
1755 Texas Instruments TMS320C6x tic6x-*-*
1759 Renesas RL78 rl78-*-elf
1761 *** Changes in GDB 7.3.1
1763 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1765 *** Changes in GDB 7.3
1767 * GDB has a new command: "thread find [REGEXP]".
1768 It finds the thread id whose name, target id, or thread extra info
1769 matches the given regular expression.
1771 * The "catch syscall" command now works on mips*-linux* targets.
1773 * The -data-disassemble MI command now supports modes 2 and 3 for
1774 dumping the instruction opcodes.
1776 * New command line options
1778 -data-directory DIR Specify DIR as the "data-directory".
1779 This is mostly for testing purposes.
1781 * The "maint set python auto-load on|off" command has been renamed to
1782 "set auto-load-scripts on|off".
1784 * GDB has a new command: "set directories".
1785 It is like the "dir" command except that it replaces the
1786 source path list instead of augmenting it.
1788 * GDB now understands thread names.
1790 On GNU/Linux, "info threads" will display the thread name as set by
1791 prctl or pthread_setname_np.
1793 There is also a new command, "thread name", which can be used to
1794 assign a name internally for GDB to display.
1797 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1798 has been integrated into GDB.
1802 ** The function gdb.Write now accepts an optional keyword 'stream'.
1803 This keyword, when provided, will direct the output to either
1804 stdout, stderr, or GDB's logging output.
1806 ** Parameters can now be be sub-classed in Python, and in particular
1807 you may implement the get_set_doc and get_show_doc functions.
1808 This improves how Parameter set/show documentation is processed
1809 and allows for more dynamic content.
1811 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1812 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1813 have an is_valid method.
1815 ** Breakpoints can now be sub-classed in Python, and in particular
1816 you may implement a 'stop' function that is executed each time
1817 the inferior reaches that breakpoint.
1819 ** New function gdb.lookup_global_symbol looks up a global symbol.
1821 ** GDB values in Python are now callable if the value represents a
1822 function. For example, if 'some_value' represents a function that
1823 takes two integer parameters and returns a value, you can call
1824 that function like so:
1826 result = some_value (10,20)
1828 ** Module gdb.types has been added.
1829 It contains a collection of utilities for working with gdb.Types objects:
1830 get_basic_type, has_field, make_enum_dict.
1832 ** Module gdb.printing has been added.
1833 It contains utilities for writing and registering pretty-printers.
1834 New classes: PrettyPrinter, SubPrettyPrinter,
1835 RegexpCollectionPrettyPrinter.
1836 New function: register_pretty_printer.
1838 ** New commands "info pretty-printers", "enable pretty-printer" and
1839 "disable pretty-printer" have been added.
1841 ** gdb.parameter("directories") is now available.
1843 ** New function gdb.newest_frame returns the newest frame in the
1846 ** The gdb.InferiorThread class has a new "name" attribute. This
1847 holds the thread's name.
1849 ** Python Support for Inferior events.
1850 Python scripts can add observers to be notified of events
1851 occurring in the process being debugged.
1852 The following events are currently supported:
1853 - gdb.events.cont Continue event.
1854 - gdb.events.exited Inferior exited event.
1855 - gdb.events.stop Signal received, and Breakpoint hit events.
1859 ** GDB now puts template parameters in scope when debugging in an
1860 instantiation. For example, if you have:
1862 template<int X> int func (void) { return X; }
1864 then if you step into func<5>, "print X" will show "5". This
1865 feature requires proper debuginfo support from the compiler; it
1866 was added to GCC 4.5.
1868 ** The motion commands "next", "finish", "until", and "advance" now
1869 work better when exceptions are thrown. In particular, GDB will
1870 no longer lose control of the inferior; instead, the GDB will
1871 stop the inferior at the point at which the exception is caught.
1872 This functionality requires a change in the exception handling
1873 code that was introduced in GCC 4.5.
1875 * GDB now follows GCC's rules on accessing volatile objects when
1876 reading or writing target state during expression evaluation.
1877 One notable difference to prior behavior is that "print x = 0"
1878 no longer generates a read of x; the value of the assignment is
1879 now always taken directly from the value being assigned.
1881 * GDB now has some support for using labels in the program's source in
1882 linespecs. For instance, you can use "advance label" to continue
1883 execution to a label.
1885 * GDB now has support for reading and writing a new .gdb_index
1886 section. This section holds a fast index of DWARF debugging
1887 information and can be used to greatly speed up GDB startup and
1888 operation. See the documentation for `save gdb-index' for details.
1890 * The "watch" command now accepts an optional "-location" argument.
1891 When used, this causes GDB to watch the memory referred to by the
1892 expression. Such a watchpoint is never deleted due to it going out
1895 * GDB now supports thread debugging of core dumps on GNU/Linux.
1897 GDB now activates thread debugging using the libthread_db library
1898 when debugging GNU/Linux core dumps, similarly to when debugging
1899 live processes. As a result, when debugging a core dump file, GDB
1900 is now able to display pthread_t ids of threads. For example, "info
1901 threads" shows the same output as when debugging the process when it
1902 was live. In earlier releases, you'd see something like this:
1905 * 1 LWP 6780 main () at main.c:10
1907 While now you see this:
1910 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1912 It is also now possible to inspect TLS variables when debugging core
1915 When debugging a core dump generated on a machine other than the one
1916 used to run GDB, you may need to point GDB at the correct
1917 libthread_db library with the "set libthread-db-search-path"
1918 command. See the user manual for more details on this command.
1920 * When natively debugging programs on PowerPC BookE processors running
1921 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1922 which stop execution of the inferior whenever it executes an instruction
1923 at any address within the specified range. See the "PowerPC Embedded"
1924 section in the user manual for more details.
1926 * New features in the GDB remote stub, GDBserver
1928 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1929 and i686 LynxOS (version 5.x).
1931 ** GDBserver is now supported on Blackfin Linux.
1933 * New native configurations
1935 ia64 HP-UX ia64-*-hpux*
1939 Analog Devices, Inc. Blackfin Processor bfin-*
1941 * Ada task switching is now supported on sparc-elf targets when
1942 debugging a program using the Ravenscar Profile. For more information,
1943 see the "Tasking Support when using the Ravenscar Profile" section
1944 in the GDB user manual.
1946 * Guile support was removed.
1948 * New features in the GNU simulator
1950 ** The --map-info flag lists all known core mappings.
1952 ** CFI flashes may be simulated via the "cfi" device.
1954 *** Changes in GDB 7.2
1956 * Shared library support for remote targets by default
1958 When GDB is configured for a generic, non-OS specific target, like
1959 for example, --target=arm-eabi or one of the many *-*-elf targets,
1960 GDB now queries remote stubs for loaded shared libraries using the
1961 `qXfer:libraries:read' packet. Previously, shared library support
1962 was always disabled for such configurations.
1966 ** Argument Dependent Lookup (ADL)
1968 In C++ ADL lookup directs function search to the namespaces of its
1969 arguments even if the namespace has not been imported.
1979 Here the compiler will search for `foo' in the namespace of 'b'
1980 and find A::foo. GDB now supports this. This construct is commonly
1981 used in the Standard Template Library for operators.
1983 ** Improved User Defined Operator Support
1985 In addition to member operators, GDB now supports lookup of operators
1986 defined in a namespace and imported with a `using' directive, operators
1987 defined in the global scope, operators imported implicitly from an
1988 anonymous namespace, and the ADL operators mentioned in the previous
1990 GDB now also supports proper overload resolution for all the previously
1991 mentioned flavors of operators.
1993 ** static const class members
1995 Printing of static const class members that are initialized in the
1996 class definition has been fixed.
1998 * Windows Thread Information Block access.
2000 On Windows targets, GDB now supports displaying the Windows Thread
2001 Information Block (TIB) structure. This structure is visible either
2002 by using the new command `info w32 thread-information-block' or, by
2003 dereferencing the new convenience variable named `$_tlb', a
2004 thread-specific pointer to the TIB. This feature is also supported
2005 when remote debugging using GDBserver.
2007 * Static tracepoints
2009 Static tracepoints are calls in the user program into a tracing
2010 library. One such library is a port of the LTTng kernel tracer to
2011 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2012 When debugging with GDBserver, GDB now supports combining the GDB
2013 tracepoint machinery with such libraries. For example: the user can
2014 use GDB to probe a static tracepoint marker (a call from the user
2015 program into the tracing library) with the new "strace" command (see
2016 "New commands" below). This creates a "static tracepoint" in the
2017 breakpoint list, that can be manipulated with the same feature set
2018 as fast and regular tracepoints. E.g., collect registers, local and
2019 global variables, collect trace state variables, and define
2020 tracepoint conditions. In addition, the user can collect extra
2021 static tracepoint marker specific data, by collecting the new
2022 $_sdata internal variable. When analyzing the trace buffer, you can
2023 inspect $_sdata like any other variable available to GDB. For more
2024 information, see the "Tracepoints" chapter in GDB user manual. New
2025 remote packets have been defined to support static tracepoints, see
2026 the "New remote packets" section below.
2028 * Better reconstruction of tracepoints after disconnected tracing
2030 GDB will attempt to download the original source form of tracepoint
2031 definitions when starting a trace run, and then will upload these
2032 upon reconnection to the target, resulting in a more accurate
2033 reconstruction of the tracepoints that are in use on the target.
2037 You can now exercise direct control over the ways that GDB can
2038 affect your program. For instance, you can disallow the setting of
2039 breakpoints, so that the program can run continuously (assuming
2040 non-stop mode). In addition, the "observer" variable is available
2041 to switch all of the different controls; in observer mode, GDB
2042 cannot affect the target's behavior at all, which is useful for
2043 tasks like diagnosing live systems in the field.
2045 * The new convenience variable $_thread holds the number of the
2048 * New remote packets
2052 Return the address of the Windows Thread Information Block of a given thread.
2056 In response to several of the tracepoint packets, the target may now
2057 also respond with a number of intermediate `qRelocInsn' request
2058 packets before the final result packet, to have GDB handle
2059 relocating an instruction to execute at a different address. This
2060 is particularly useful for stubs that support fast tracepoints. GDB
2061 reports support for this feature in the qSupported packet.
2065 List static tracepoint markers in the target program.
2069 List static tracepoint markers at a given address in the target
2072 qXfer:statictrace:read
2074 Read the static trace data collected (by a `collect $_sdata'
2075 tracepoint action). The remote stub reports support for this packet
2076 to gdb's qSupported query.
2080 Send the current settings of GDB's permission flags.
2084 Send part of the source (textual) form of a tracepoint definition,
2085 which includes location, conditional, and action list.
2087 * The source command now accepts a -s option to force searching for the
2088 script in the source search path even if the script name specifies
2091 * New features in the GDB remote stub, GDBserver
2093 - GDBserver now support tracepoints (including fast tracepoints, and
2094 static tracepoints). The feature is currently supported by the
2095 i386-linux and amd64-linux builds. See the "Tracepoints support
2096 in gdbserver" section in the manual for more information.
2098 GDBserver JIT compiles the tracepoint's conditional agent
2099 expression bytecode into native code whenever possible for low
2100 overhead dynamic tracepoints conditionals. For such tracepoints,
2101 an expression that examines program state is evaluated when the
2102 tracepoint is reached, in order to determine whether to capture
2103 trace data. If the condition is simple and false, processing the
2104 tracepoint finishes very quickly and no data is gathered.
2106 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2107 for static tracepoints support.
2109 - GDBserver now supports x86_64 Windows 64-bit debugging.
2111 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2112 it understands register description.
2114 * The --batch flag now disables pagination and queries.
2116 * X86 general purpose registers
2118 GDB now supports reading/writing byte, word and double-word x86
2119 general purpose registers directly. This means you can use, say,
2120 $ah or $ax to refer, respectively, to the byte register AH and
2121 16-bit word register AX that are actually portions of the 32-bit
2122 register EAX or 64-bit register RAX.
2124 * The `commands' command now accepts a range of breakpoints to modify.
2125 A plain `commands' following a command that creates multiple
2126 breakpoints affects all the breakpoints set by that command. This
2127 applies to breakpoints set by `rbreak', and also applies when a
2128 single `break' command creates multiple breakpoints (e.g.,
2129 breakpoints on overloaded c++ functions).
2131 * The `rbreak' command now accepts a filename specification as part of
2132 its argument, limiting the functions selected by the regex to those
2133 in the specified file.
2135 * Support for remote debugging Windows and SymbianOS shared libraries
2136 from Unix hosts has been improved. Non Windows GDB builds now can
2137 understand target reported file names that follow MS-DOS based file
2138 system semantics, such as file names that include drive letters and
2139 use the backslash character as directory separator. This makes it
2140 possible to transparently use the "set sysroot" and "set
2141 solib-search-path" on Unix hosts to point as host copies of the
2142 target's shared libraries. See the new command "set
2143 target-file-system-kind" described below, and the "Commands to
2144 specify files" section in the user manual for more information.
2148 eval template, expressions...
2149 Convert the values of one or more expressions under the control
2150 of the string template to a command line, and call it.
2152 set target-file-system-kind unix|dos-based|auto
2153 show target-file-system-kind
2154 Set or show the assumed file system kind for target reported file
2157 save breakpoints <filename>
2158 Save all current breakpoint definitions to a file suitable for use
2159 in a later debugging session. To read the saved breakpoint
2160 definitions, use the `source' command.
2162 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2165 info static-tracepoint-markers
2166 Display information about static tracepoint markers in the target.
2168 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2169 Define a static tracepoint by probing a marker at the given
2170 function, line, address, or marker ID.
2174 Enable and disable observer mode.
2176 set may-write-registers on|off
2177 set may-write-memory on|off
2178 set may-insert-breakpoints on|off
2179 set may-insert-tracepoints on|off
2180 set may-insert-fast-tracepoints on|off
2181 set may-interrupt on|off
2182 Set individual permissions for GDB effects on the target. Note that
2183 some of these settings can have undesirable or surprising
2184 consequences, particularly when changed in the middle of a session.
2185 For instance, disabling the writing of memory can prevent
2186 breakpoints from being inserted, cause single-stepping to fail, or
2187 even crash your program, if you disable after breakpoints have been
2188 inserted. However, GDB should not crash.
2190 set record memory-query on|off
2191 show record memory-query
2192 Control whether to stop the inferior if memory changes caused
2193 by an instruction cannot be recorded.
2198 The disassemble command now supports "start,+length" form of two arguments.
2202 ** GDB now provides a new directory location, called the python directory,
2203 where Python scripts written for GDB can be installed. The location
2204 of that directory is <data-directory>/python, where <data-directory>
2205 is the GDB data directory. For more details, see section `Scripting
2206 GDB using Python' in the manual.
2208 ** The GDB Python API now has access to breakpoints, symbols, symbol
2209 tables, program spaces, inferiors, threads and frame's code blocks.
2210 Additionally, GDB Parameters can now be created from the API, and
2211 manipulated via set/show in the CLI.
2213 ** New functions gdb.target_charset, gdb.target_wide_charset,
2214 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2216 ** New exception gdb.GdbError.
2218 ** Pretty-printers are now also looked up in the current program space.
2220 ** Pretty-printers can now be individually enabled and disabled.
2222 ** GDB now looks for names of Python scripts to auto-load in a
2223 special section named `.debug_gdb_scripts', in addition to looking
2224 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2226 * Tracepoint actions were unified with breakpoint commands. In particular,
2227 there are no longer differences in "info break" output for breakpoints and
2228 tracepoints and the "commands" command can be used for both tracepoints and
2229 regular breakpoints.
2233 ARM Symbian arm*-*-symbianelf*
2235 * D language support.
2236 GDB now supports debugging programs written in the D programming
2239 * GDB now supports the extended ptrace interface for PowerPC which is
2240 available since Linux kernel version 2.6.34. This automatically enables
2241 any hardware breakpoints and additional hardware watchpoints available in
2242 the processor. The old ptrace interface exposes just one hardware
2243 watchpoint and no hardware breakpoints.
2245 * GDB is now able to use the Data Value Compare (DVC) register available on
2246 embedded PowerPC processors to implement in hardware simple watchpoint
2247 conditions of the form:
2249 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2251 This works in native GDB running on Linux kernels with the extended ptrace
2252 interface mentioned above.
2254 *** Changes in GDB 7.1
2258 ** Namespace Support
2260 GDB now supports importing of namespaces in C++. This enables the
2261 user to inspect variables from imported namespaces. Support for
2262 namepace aliasing has also been added. So, if a namespace is
2263 aliased in the current scope (e.g. namepace C=A; ) the user can
2264 print variables using the alias (e.g. (gdb) print C::x).
2268 All known bugs relating to the printing of virtual base class were
2269 fixed. It is now possible to call overloaded static methods using a
2274 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2275 and reinterpret_cast<> are now handled by the C++ expression parser.
2279 Xilinx MicroBlaze microblaze-*-*
2284 Xilinx MicroBlaze microblaze
2287 * Multi-program debugging.
2289 GDB now has support for multi-program (a.k.a. multi-executable or
2290 multi-exec) debugging. This allows for debugging multiple inferiors
2291 simultaneously each running a different program under the same GDB
2292 session. See "Debugging Multiple Inferiors and Programs" in the
2293 manual for more information. This implied some user visible changes
2294 in the multi-inferior support. For example, "info inferiors" now
2295 lists inferiors that are not running yet or that have exited
2296 already. See also "New commands" and "New options" below.
2298 * New tracing features
2300 GDB's tracepoint facility now includes several new features:
2302 ** Trace state variables
2304 GDB tracepoints now include support for trace state variables, which
2305 are variables managed by the target agent during a tracing
2306 experiment. They are useful for tracepoints that trigger each
2307 other, so for instance one tracepoint can count hits in a variable,
2308 and then a second tracepoint has a condition that is true when the
2309 count reaches a particular value. Trace state variables share the
2310 $-syntax of GDB convenience variables, and can appear in both
2311 tracepoint actions and condition expressions. Use the "tvariable"
2312 command to create, and "info tvariables" to view; see "Trace State
2313 Variables" in the manual for more detail.
2317 GDB now includes an option for defining fast tracepoints, which
2318 targets may implement more efficiently, such as by installing a jump
2319 into the target agent rather than a trap instruction. The resulting
2320 speedup can be by two orders of magnitude or more, although the
2321 tradeoff is that some program locations on some target architectures
2322 might not allow fast tracepoint installation, for instance if the
2323 instruction to be replaced is shorter than the jump. To request a
2324 fast tracepoint, use the "ftrace" command, with syntax identical to
2325 the regular trace command.
2327 ** Disconnected tracing
2329 It is now possible to detach GDB from the target while it is running
2330 a trace experiment, then reconnect later to see how the experiment
2331 is going. In addition, a new variable disconnected-tracing lets you
2332 tell the target agent whether to continue running a trace if the
2333 connection is lost unexpectedly.
2337 GDB now has the ability to save the trace buffer into a file, and
2338 then use that file as a target, similarly to you can do with
2339 corefiles. You can select trace frames, print data that was
2340 collected in them, and use tstatus to display the state of the
2341 tracing run at the moment that it was saved. To create a trace
2342 file, use "tsave <filename>", and to use it, do "target tfile
2345 ** Circular trace buffer
2347 You can ask the target agent to handle the trace buffer as a
2348 circular buffer, discarding the oldest trace frames to make room for
2349 newer ones, by setting circular-trace-buffer to on. This feature may
2350 not be available for all target agents.
2355 The disassemble command, when invoked with two arguments, now requires
2356 the arguments to be comma-separated.
2359 The info variables command now displays variable definitions. Files
2360 which only declare a variable are not shown.
2363 The source command is now capable of sourcing Python scripts.
2364 This feature is dependent on the debugger being build with Python
2367 Related to this enhancement is also the introduction of a new command
2368 "set script-extension" (see below).
2370 * New commands (for set/show, see "New options" below)
2372 record save [<FILENAME>]
2373 Save a file (in core file format) containing the process record
2374 execution log for replay debugging at a later time.
2376 record restore <FILENAME>
2377 Restore the process record execution log that was saved at an
2378 earlier time, for replay debugging.
2380 add-inferior [-copies <N>] [-exec <FILENAME>]
2383 clone-inferior [-copies <N>] [ID]
2384 Make a new inferior ready to execute the same program another
2385 inferior has loaded.
2390 maint info program-spaces
2391 List the program spaces loaded into GDB.
2393 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2394 show remote interrupt-sequence
2395 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2396 as the sequence to the remote target in order to interrupt the execution.
2397 Ctrl-C is a default. Some system prefers BREAK which is high level of
2398 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2399 Magic SysRq g. It is BREAK signal and character 'g'.
2401 set remote interrupt-on-connect [on | off]
2402 show remote interrupt-on-connect
2403 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2404 remote target when gdb connects to it. This is needed when you debug
2407 set remotebreak [on | off]
2409 Deprecated. Use "set/show remote interrupt-sequence" instead.
2411 tvariable $NAME [ = EXP ]
2412 Create or modify a trace state variable.
2415 List trace state variables and their values.
2417 delete tvariable $NAME ...
2418 Delete one or more trace state variables.
2421 Evaluate the given expressions without collecting anything into the
2422 trace buffer. (Valid in tracepoint actions only.)
2424 ftrace FN / FILE:LINE / *ADDR
2425 Define a fast tracepoint at the given function, line, or address.
2427 * New expression syntax
2429 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2430 GDB now parses 0b101010 identically with 42.
2434 set follow-exec-mode new|same
2435 show follow-exec-mode
2436 Control whether GDB reuses the same inferior across an exec call or
2437 creates a new one. This is useful to be able to restart the old
2438 executable after the inferior having done an exec call.
2440 set default-collect EXPR, ...
2441 show default-collect
2442 Define a list of expressions to be collected at each tracepoint.
2443 This is a useful way to ensure essential items are not overlooked,
2444 such as registers or a critical global variable.
2446 set disconnected-tracing
2447 show disconnected-tracing
2448 If set to 1, the target is instructed to continue tracing if it
2449 loses its connection to GDB. If 0, the target is to stop tracing
2452 set circular-trace-buffer
2453 show circular-trace-buffer
2454 If set to on, the target is instructed to use a circular trace buffer
2455 and discard the oldest trace frames instead of stopping the trace due
2456 to a full trace buffer. If set to off, the trace stops when the buffer
2457 fills up. Some targets may not support this.
2459 set script-extension off|soft|strict
2460 show script-extension
2461 If set to "off", the debugger does not perform any script language
2462 recognition, and all sourced files are assumed to be GDB scripts.
2463 If set to "soft" (the default), files are sourced according to
2464 filename extension, falling back to GDB scripts if the first
2466 If set to "strict", files are sourced according to filename extension.
2468 set ada trust-PAD-over-XVS on|off
2469 show ada trust-PAD-over-XVS
2470 If off, activate a workaround against a bug in the debugging information
2471 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2472 the GCC sources for more information about the GNAT encoding and
2473 PAD types in particular). It is always safe to set this option to
2474 off, but this introduces a slight performance penalty. The default
2477 * Python API Improvements
2479 ** GDB provides the new class gdb.LazyString. This is useful in
2480 some pretty-printing cases. The new method gdb.Value.lazy_string
2481 provides a simple way to create objects of this type.
2483 ** The fields returned by gdb.Type.fields now have an
2484 `is_base_class' attribute.
2486 ** The new method gdb.Type.range returns the range of an array type.
2488 ** The new method gdb.parse_and_eval can be used to parse and
2489 evaluate an expression.
2491 * New remote packets
2494 Define a trace state variable.
2497 Get the current value of a trace state variable.
2500 Set desired tracing behavior upon disconnection.
2503 Set the trace buffer to be linear or circular.
2506 Get data about the tracepoints currently in use.
2510 Process record now works correctly with hardware watchpoints.
2512 Multiple bug fixes have been made to the mips-irix port, making it
2513 much more reliable. In particular:
2514 - Debugging threaded applications is now possible again. Previously,
2515 GDB would hang while starting the program, or while waiting for
2516 the program to stop at a breakpoint.
2517 - Attaching to a running process no longer hangs.
2518 - An error occurring while loading a core file has been fixed.
2519 - Changing the value of the PC register now works again. This fixes
2520 problems observed when using the "jump" command, or when calling
2521 a function from GDB, or even when assigning a new value to $pc.
2522 - With the "finish" and "return" commands, the return value for functions
2523 returning a small array is now correctly printed.
2524 - It is now possible to break on shared library code which gets executed
2525 during a shared library init phase (code executed while executing
2526 their .init section). Previously, the breakpoint would have no effect.
2527 - GDB is now able to backtrace through the signal handler for
2528 non-threaded programs.
2530 PIE (Position Independent Executable) programs debugging is now supported.
2531 This includes debugging execution of PIC (Position Independent Code) shared
2532 libraries although for that, it should be possible to run such libraries as an
2535 *** Changes in GDB 7.0
2537 * GDB now has an interface for JIT compilation. Applications that
2538 dynamically generate code can create symbol files in memory and register
2539 them with GDB. For users, the feature should work transparently, and
2540 for JIT developers, the interface is documented in the GDB manual in the
2541 "JIT Compilation Interface" chapter.
2543 * Tracepoints may now be conditional. The syntax is as for
2544 breakpoints; either an "if" clause appended to the "trace" command,
2545 or the "condition" command is available. GDB sends the condition to
2546 the target for evaluation using the same bytecode format as is used
2547 for tracepoint actions.
2549 * The disassemble command now supports: an optional /r modifier, print the
2550 raw instructions in hex as well as in symbolic form, and an optional /m
2551 modifier to print mixed source+assembly.
2553 * Process record and replay
2555 In a architecture environment that supports ``process record and
2556 replay'', ``process record and replay'' target can record a log of
2557 the process execution, and replay it with both forward and reverse
2560 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2561 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2562 set execution-direction {forward|reverse}, for targets that support
2565 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2566 feature is available with a native GDB running on kernel version
2569 * GDB now has support for multi-byte and wide character sets on the
2570 target. Strings whose character type is wchar_t, char16_t, or
2571 char32_t are now correctly printed. GDB supports wide- and unicode-
2572 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2573 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2574 `printf'. This feature requires iconv to work properly; if your
2575 system does not have a working iconv, GDB can use GNU libiconv. See
2576 the installation instructions for more information.
2578 * GDB now supports automatic retrieval of shared library files from
2579 remote targets. To use this feature, specify a system root that begins
2580 with the `remote:' prefix, either via the `set sysroot' command or via
2581 the `--with-sysroot' configure-time option.
2583 * "info sharedlibrary" now takes an optional regex of libraries to show,
2584 and it now reports if a shared library has no debugging information.
2586 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2587 now complete on file names.
2589 * When completing in expressions, gdb will attempt to limit
2590 completions to allowable structure or union fields, where appropriate.
2591 For instance, consider:
2593 # struct example { int f1; double f2; };
2594 # struct example variable;
2597 If the user types TAB at the end of this command line, the available
2598 completions will be "f1" and "f2".
2600 * Inlined functions are now supported. They show up in backtraces, and
2601 the "step", "next", and "finish" commands handle them automatically.
2603 * GDB now supports the token-splicing (##) and stringification (#)
2604 operators when expanding macros. It also supports variable-arity
2607 * GDB now supports inspecting extra signal information, exported by
2608 the new $_siginfo convenience variable. The feature is currently
2609 implemented on linux ARM, i386 and amd64.
2611 * GDB can now display the VFP floating point registers and NEON vector
2612 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2613 can provide these registers (requires Linux 2.6.30 or later). Remote
2614 and simulator targets may also provide them.
2616 * New remote packets
2619 Search memory for a sequence of bytes.
2622 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2623 operation over reliable transport links. Use of this packet is
2624 controlled by the `set remote noack-packet' command.
2627 Kill the process with the specified process ID. Use this in preference
2628 to `k' when multiprocess protocol extensions are supported.
2631 Obtains additional operating system information
2635 Read or write additional signal information.
2637 * Removed remote protocol undocumented extension
2639 An undocumented extension to the remote protocol's `S' stop reply
2640 packet that permited the stub to pass a process id was removed.
2641 Remote servers should use the `T' stop reply packet instead.
2643 * GDB now supports multiple function calling conventions according to the
2644 DWARF-2 DW_AT_calling_convention function attribute.
2646 * The SH target utilizes the aforementioned change to distinguish between gcc
2647 and Renesas calling convention. It also adds the new CLI commands
2648 `set/show sh calling-convention'.
2650 * GDB can now read compressed debug sections, as produced by GNU gold
2651 with the --compress-debug-sections=zlib flag.
2653 * 64-bit core files are now supported on AIX.
2655 * Thread switching is now supported on Tru64.
2657 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2658 which will be allocated using malloc later in program execution.
2660 * The qXfer:libraries:read remote procotol packet now allows passing a
2661 list of section offsets.
2663 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2664 conditions handling signals delivered during attach or thread creation
2665 have also been fixed.
2667 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2668 From the user's standpoint, all unqualified instances of True and False
2669 are treated as the standard definitions, regardless of context.
2671 * GDB now parses C++ symbol and type names more flexibly. For
2674 template<typename T> class C { };
2677 GDB will now correctly handle all of:
2679 ptype C<char const *>
2680 ptype C<char const*>
2681 ptype C<const char *>
2682 ptype C<const char*>
2684 * New features in the GDB remote stub, gdbserver
2686 - The "--wrapper" command-line argument tells gdbserver to use a
2687 wrapper program to launch programs for debugging.
2689 - On PowerPC and S/390 targets, it is now possible to use a single
2690 gdbserver executable to debug both 32-bit and 64-bit programs.
2691 (This requires gdbserver itself to be built as a 64-bit executable.)
2693 - gdbserver uses the new noack protocol mode for TCP connections to
2694 reduce communications latency, if also supported and enabled in GDB.
2696 - Support for the sparc64-linux-gnu target is now included in
2699 - The amd64-linux build of gdbserver now supports debugging both
2700 32-bit and 64-bit programs.
2702 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2703 now support hardware watchpoints, and will use them automatically
2708 GDB now has support for scripting using Python. Whether this is
2709 available is determined at configure time.
2711 New GDB commands can now be written in Python.
2713 * Ada tasking support
2715 Ada tasks can now be inspected in GDB. The following commands have
2719 Print the list of Ada tasks.
2721 Print detailed information about task number N.
2723 Print the task number of the current task.
2725 Switch the context of debugging to task number N.
2727 * Support for user-defined prefixed commands. The "define" command can
2728 add new commands to existing prefixes, e.g. "target".
2730 * Multi-inferior, multi-process debugging.
2732 GDB now has generalized support for multi-inferior debugging. See
2733 "Debugging Multiple Inferiors" in the manual for more information.
2734 Although availability still depends on target support, the command
2735 set is more uniform now. The GNU/Linux specific multi-forks support
2736 has been migrated to this new framework. This implied some user
2737 visible changes; see "New commands" and also "Removed commands"
2740 * Target descriptions can now describe the target OS ABI. See the
2741 "Target Description Format" section in the user manual for more
2744 * Target descriptions can now describe "compatible" architectures
2745 to indicate that the target can execute applications for a different
2746 architecture in addition to those for the main target architecture.
2747 See the "Target Description Format" section in the user manual for
2750 * Multi-architecture debugging.
2752 GDB now includes general supports for debugging applications on
2753 hybrid systems that use more than one single processor architecture
2754 at the same time. Each such hybrid architecture still requires
2755 specific support to be added. The only hybrid architecture supported
2756 in this version of GDB is the Cell Broadband Engine.
2758 * GDB now supports integrated debugging of Cell/B.E. applications that
2759 use both the PPU and SPU architectures. To enable support for hybrid
2760 Cell/B.E. debugging, you need to configure GDB to support both the
2761 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2762 --enable-targets configure option.
2764 * Non-stop mode debugging.
2766 For some targets, GDB now supports an optional mode of operation in
2767 which you can examine stopped threads while other threads continue
2768 to execute freely. This is referred to as non-stop mode, with the
2769 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2770 section in the user manual for more information.
2772 To be able to support remote non-stop debugging, a remote stub needs
2773 to implement the non-stop mode remote protocol extensions, as
2774 described in the "Remote Non-Stop" section of the user manual. The
2775 GDB remote stub, gdbserver, has been adjusted to support these
2776 extensions on linux targets.
2778 * New commands (for set/show, see "New options" below)
2780 catch syscall [NAME(S) | NUMBER(S)]
2781 Catch system calls. Arguments, which should be names of system
2782 calls or their numbers, mean catch only those syscalls. Without
2783 arguments, every syscall will be caught. When the inferior issues
2784 any of the specified syscalls, GDB will stop and announce the system
2785 call, both when it is called and when its call returns. This
2786 feature is currently available with a native GDB running on the
2787 Linux Kernel, under the following architectures: x86, x86_64,
2788 PowerPC and PowerPC64.
2790 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2792 Search memory for a sequence of bytes.
2794 maint set python print-stack
2795 maint show python print-stack
2796 Show a stack trace when an error is encountered in a Python script.
2799 Invoke CODE by passing it to the Python interpreter.
2804 These allow macros to be defined, undefined, and listed
2808 Show operating system information about processes.
2811 List the inferiors currently under GDB's control.
2814 Switch focus to inferior number NUM.
2817 Detach from inferior number NUM.
2820 Kill inferior number NUM.
2824 set spu stop-on-load
2825 show spu stop-on-load
2826 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2828 set spu auto-flush-cache
2829 show spu auto-flush-cache
2830 Control whether to automatically flush the software-managed cache
2831 during Cell/B.E. debugging.
2833 set sh calling-convention
2834 show sh calling-convention
2835 Control the calling convention used when calling SH target functions.
2838 show debug timestamp
2839 Control display of timestamps with GDB debugging output.
2841 set disassemble-next-line
2842 show disassemble-next-line
2843 Control display of disassembled source lines or instructions when
2846 set remote noack-packet
2847 show remote noack-packet
2848 Set/show the use of remote protocol QStartNoAckMode packet. See above
2849 under "New remote packets."
2851 set remote query-attached-packet
2852 show remote query-attached-packet
2853 Control use of remote protocol `qAttached' (query-attached) packet.
2855 set remote read-siginfo-object
2856 show remote read-siginfo-object
2857 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2860 set remote write-siginfo-object
2861 show remote write-siginfo-object
2862 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2865 set remote reverse-continue
2866 show remote reverse-continue
2867 Control use of remote protocol 'bc' (reverse-continue) packet.
2869 set remote reverse-step
2870 show remote reverse-step
2871 Control use of remote protocol 'bs' (reverse-step) packet.
2873 set displaced-stepping
2874 show displaced-stepping
2875 Control displaced stepping mode. Displaced stepping is a way to
2876 single-step over breakpoints without removing them from the debuggee.
2877 Also known as "out-of-line single-stepping".
2880 show debug displaced
2881 Control display of debugging info for displaced stepping.
2883 maint set internal-error
2884 maint show internal-error
2885 Control what GDB does when an internal error is detected.
2887 maint set internal-warning
2888 maint show internal-warning
2889 Control what GDB does when an internal warning is detected.
2894 Use a wrapper program to launch programs for debugging.
2896 set multiple-symbols (all|ask|cancel)
2897 show multiple-symbols
2898 The value of this variable can be changed to adjust the debugger behavior
2899 when an expression or a breakpoint location contains an ambiguous symbol
2900 name (an overloaded function name, for instance).
2902 set breakpoint always-inserted
2903 show breakpoint always-inserted
2904 Keep breakpoints always inserted in the target, as opposed to inserting
2905 them when resuming the target, and removing them when the target stops.
2906 This option can improve debugger performance on slow remote targets.
2908 set arm fallback-mode (arm|thumb|auto)
2909 show arm fallback-mode
2910 set arm force-mode (arm|thumb|auto)
2912 These commands control how ARM GDB determines whether instructions
2913 are ARM or Thumb. The default for both settings is auto, which uses
2914 the current CPSR value for instructions without symbols; previous
2915 versions of GDB behaved as if "set arm fallback-mode arm".
2917 set disable-randomization
2918 show disable-randomization
2919 Standalone programs run with the virtual address space randomization enabled
2920 by default on some platforms. This option keeps the addresses stable across
2921 multiple debugging sessions.
2925 Control whether other threads are stopped or not when some thread hits
2930 Requests that asynchronous execution is enabled in the target, if available.
2931 In this case, it's possible to resume target in the background, and interact
2932 with GDB while the target is running. "show target-async" displays the
2933 current state of asynchronous execution of the target.
2935 set target-wide-charset
2936 show target-wide-charset
2937 The target-wide-charset is the name of the character set that GDB
2938 uses when printing characters whose type is wchar_t.
2940 set tcp auto-retry (on|off)
2942 set tcp connect-timeout
2943 show tcp connect-timeout
2944 These commands allow GDB to retry failed TCP connections to a remote stub
2945 with a specified timeout period; this is useful if the stub is launched
2946 in parallel with GDB but may not be ready to accept connections immediately.
2948 set libthread-db-search-path
2949 show libthread-db-search-path
2950 Control list of directories which GDB will search for appropriate
2953 set schedule-multiple (on|off)
2954 show schedule-multiple
2955 Allow GDB to resume all threads of all processes or only threads of
2956 the current process.
2960 Use more aggressive caching for accesses to the stack. This improves
2961 performance of remote debugging (particularly backtraces) without
2962 affecting correctness.
2964 set interactive-mode (on|off|auto)
2965 show interactive-mode
2966 Control whether GDB runs in interactive mode (on) or not (off).
2967 When in interactive mode, GDB waits for the user to answer all
2968 queries. Otherwise, GDB does not wait and assumes the default
2969 answer. When set to auto (the default), GDB determines which
2970 mode to use based on the stdin settings.
2975 For program forks, this is replaced by the new more generic `info
2976 inferiors' command. To list checkpoints, you can still use the
2977 `info checkpoints' command, which was an alias for the `info forks'
2981 Replaced by the new `inferior' command. To switch between
2982 checkpoints, you can still use the `restart' command, which was an
2983 alias for the `fork' command.
2986 This is removed, since some targets don't have a notion of
2987 processes. To switch between processes, you can still use the
2988 `inferior' command using GDB's own inferior number.
2991 For program forks, this is replaced by the new more generic `kill
2992 inferior' command. To delete a checkpoint, you can still use the
2993 `delete checkpoint' command, which was an alias for the `delete
2997 For program forks, this is replaced by the new more generic `detach
2998 inferior' command. To detach a checkpoint, you can still use the
2999 `detach checkpoint' command, which was an alias for the `detach
3002 * New native configurations
3004 x86/x86_64 Darwin i[34567]86-*-darwin*
3006 x86_64 MinGW x86_64-*-mingw*
3010 Lattice Mico32 lm32-*
3011 x86 DICOS i[34567]86-*-dicos*
3012 x86_64 DICOS x86_64-*-dicos*
3015 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3016 (mingw32ce) debugging.
3022 These commands were actually not implemented on any target.
3024 *** Changes in GDB 6.8
3026 * New native configurations
3028 NetBSD/hppa hppa*-*netbsd*
3029 Xtensa GNU/Linux xtensa*-*-linux*
3033 NetBSD/hppa hppa*-*-netbsd*
3034 Xtensa GNU/Lunux xtensa*-*-linux*
3036 * Change in command line behavior -- corefiles vs. process ids.
3038 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3039 attaching to process NUMBER fails, GDB no longer attempts to open a
3040 core file named NUMBER. Attaching to a program using the -c option
3041 is no longer supported. Instead, use the '-p' or '--pid' options.
3043 * GDB can now be built as a native debugger for debugging Windows x86
3044 (mingw32) Portable Executable (PE) programs.
3046 * Pending breakpoints no longer change their number when their address
3049 * GDB now supports breakpoints with multiple locations,
3050 including breakpoints on C++ constructors, inside C++ templates,
3051 and in inlined functions.
3053 * GDB's ability to debug optimized code has been improved. GDB more
3054 accurately identifies function bodies and lexical blocks that occupy
3055 more than one contiguous range of addresses.
3057 * Target descriptions can now describe registers for PowerPC.
3059 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3060 registers on PowerPC targets.
3062 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3063 targets even when the libthread_db library is not available.
3065 * The GDB remote stub, gdbserver, now supports the new file transfer
3066 commands (remote put, remote get, and remote delete).
3068 * The GDB remote stub, gdbserver, now supports run and attach in
3069 extended-remote mode.
3071 * hppa*64*-*-hpux11* target broken
3072 The debugger is unable to start a program and fails with the following
3073 error: "Error trying to get information about dynamic linker".
3074 The gdb-6.7 release is also affected.
3076 * GDB now supports the --enable-targets= configure option to allow
3077 building a single GDB executable that supports multiple remote
3078 target architectures.
3080 * GDB now supports debugging C and C++ programs which use the
3081 Decimal Floating Point extension. In addition, the PowerPC target
3082 now has a set of pseudo-registers to inspect decimal float values
3083 stored in two consecutive float registers.
3085 * The -break-insert MI command can optionally create pending
3088 * Improved support for debugging Ada
3089 Many improvements to the Ada language support have been made. These
3091 - Better support for Ada2005 interface types
3092 - Improved handling of arrays and slices in general
3093 - Better support for Taft-amendment types
3094 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3096 - Improved command completion in Ada
3099 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3104 set print frame-arguments (all|scalars|none)
3105 show print frame-arguments
3106 The value of this variable can be changed to control which argument
3107 values should be printed by the debugger when displaying a frame.
3112 Transfer files to and from a remote target, and delete remote files.
3119 Transfer files to and from a remote target, and delete remote files.
3121 * New remote packets
3128 Open, close, read, write, and delete files on the remote system.
3131 Attach to an existing process on the remote system, in extended-remote
3135 Run a new process on the remote system, in extended-remote mode.
3137 *** Changes in GDB 6.7
3139 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3140 bfd, libiberty and opcodes, as revealed by static analysis donated by
3141 Coverity, Inc. (http://scan.coverity.com).
3143 * When looking up multiply-defined global symbols, GDB will now prefer the
3144 symbol definition in the current shared library if it was built using the
3145 -Bsymbolic linker option.
3147 * When the Text User Interface (TUI) is not configured, GDB will now
3148 recognize the -tui command-line option and print a message that the TUI
3151 * The GDB remote stub, gdbserver, now has lower overhead for high
3152 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3154 * GDB for MIPS targets now autodetects whether a remote target provides
3155 32-bit or 64-bit register values.
3157 * Support for C++ member pointers has been improved.
3159 * GDB now understands XML target descriptions, which specify the
3160 target's overall architecture. GDB can read a description from
3161 a local file or over the remote serial protocol.
3163 * Vectors of single-byte data use a new integer type which is not
3164 automatically displayed as character or string data.
3166 * The /s format now works with the print command. It displays
3167 arrays of single-byte integers and pointers to single-byte integers
3170 * Target descriptions can now describe target-specific registers,
3171 for architectures which have implemented the support (currently
3172 only ARM, M68K, and MIPS).
3174 * GDB and the GDB remote stub, gdbserver, now support the XScale
3177 * The GDB remote stub, gdbserver, has been updated to support
3178 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3179 has been rewritten to use the standard GDB remote protocol.
3181 * GDB can now step into C++ functions which are called through thunks.
3183 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3185 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3186 layout. It also supports a TextSeg= and DataSeg= response when only
3187 segment base addresses (rather than offsets) are available.
3189 * The /i format now outputs any trailing branch delay slot instructions
3190 immediately following the last instruction within the count specified.
3192 * The GDB remote protocol "T" stop reply packet now supports a
3193 "library" response. Combined with the new "qXfer:libraries:read"
3194 packet, this response allows GDB to debug shared libraries on targets
3195 where the operating system manages the list of loaded libraries (e.g.
3196 Windows and SymbianOS).
3198 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3199 (DLLs) on Windows and Windows CE targets.
3201 * GDB now supports a faster verification that a .debug file matches its binary
3202 according to its build-id signature, if the signature is present.
3208 Enable or disable hardware flow control (RTS/CTS) on the serial port
3209 when debugging using remote targets.
3211 set mem inaccessible-by-default
3212 show mem inaccessible-by-default
3213 If the target supplies a memory map, for instance via the remote
3214 protocol's "qXfer:memory-map:read" packet, setting this variable
3215 prevents GDB from accessing memory outside the memory map. This
3216 is useful for targets with memory mapped registers or which react
3217 badly to accesses of unmapped address space.
3219 set breakpoint auto-hw
3220 show breakpoint auto-hw
3221 If the target supplies a memory map, for instance via the remote
3222 protocol's "qXfer:memory-map:read" packet, setting this variable
3223 lets GDB use hardware breakpoints automatically for memory regions
3224 where it can not use software breakpoints. This covers both the
3225 "break" command and internal breakpoints used for other commands
3226 including "next" and "finish".
3229 catch exception unhandled
3230 Stop the program execution when Ada exceptions are raised.
3233 Stop the program execution when an Ada assertion failed.
3237 Set an alternate system root for target files. This is a more
3238 general version of "set solib-absolute-prefix", which is now
3239 an alias to "set sysroot".
3242 Provide extended SPU facility status information. This set of
3243 commands is available only when debugging the Cell/B.E. SPU
3246 * New native configurations
3248 OpenBSD/sh sh*-*openbsd*
3251 unset tdesc filename
3253 Use the specified local file as an XML target description, and do
3254 not query the target for its built-in description.
3258 OpenBSD/sh sh*-*-openbsd*
3259 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3260 Toshiba Media Processor mep-elf
3262 * New remote packets
3265 Ignore the specified signals; pass them directly to the debugged program
3266 without stopping other threads or reporting them to GDB.
3268 qXfer:features:read:
3269 Read an XML target description from the target, which describes its
3274 Read or write contents of an spufs file on the target system. These
3275 packets are available only on the Cell/B.E. SPU architecture.
3277 qXfer:libraries:read:
3278 Report the loaded shared libraries. Combined with new "T" packet
3279 response, this packet allows GDB to debug shared libraries on
3280 targets where the operating system manages the list of loaded
3281 libraries (e.g. Windows and SymbianOS).
3285 Support for these obsolete configurations has been removed.
3293 i[34567]86-*-lynxos*
3294 i[34567]86-*-netware*
3295 i[34567]86-*-sco3.2v5*
3296 i[34567]86-*-sco3.2v4*
3298 i[34567]86-*-sysv4.2*
3301 i[34567]86-*-unixware2*
3302 i[34567]86-*-unixware*
3311 * Other removed features
3318 Various m68k-only ROM monitors.
3325 Various Renesas ROM monitors and debugging interfaces for SH and
3330 Support for a Macraigor serial interface to on-chip debugging.
3331 GDB does not directly support the newer parallel or USB
3336 A debug information format. The predecessor to DWARF 2 and
3337 DWARF 3, which are still supported.
3339 Support for the HP aCC compiler on HP-UX/PA-RISC
3341 SOM-encapsulated symbolic debugging information, automatic
3342 invocation of pxdb, and the aCC custom C++ ABI. This does not
3343 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3344 with aCC can still be debugged on an assembly level.
3346 MIPS ".pdr" sections
3348 A MIPS-specific format used to describe stack frame layout
3349 in debugging information.
3353 GDB could work with an older version of Guile to debug
3354 the interpreter and Scheme programs running in it.
3356 set mips stack-arg-size
3357 set mips saved-gpreg-size
3359 Use "set mips abi" to control parameter passing for MIPS.
3361 *** Changes in GDB 6.6
3366 Cell Broadband Engine SPU spu-elf
3368 * GDB can now be configured as a cross-debugger targeting native Windows
3369 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3370 running on a Windows system over TCP/IP to debug Windows programs.
3372 * The GDB remote stub, gdbserver, has been updated to support Windows and
3373 Cygwin debugging. Both single-threaded and multi-threaded programs are
3376 * The "set trust-readonly-sections" command works again. This command was
3377 broken in GDB 6.3, 6.4, and 6.5.
3379 * The "load" command now supports writing to flash memory, if the remote
3380 stub provides the required support.
3382 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3383 longer requires symbolic debug information (e.g. DWARF-2).
3388 unset substitute-path
3389 show substitute-path
3390 Manage a list of substitution rules that GDB uses to rewrite the name
3391 of the directories where the sources are located. This can be useful
3392 for instance when the sources were moved to a different location
3393 between compilation and debugging.
3397 Print each CLI command as it is executed. Each command is prefixed with
3398 a number of `+' symbols representing the nesting depth.
3399 The source command now has a `-v' option to enable the same feature.
3403 The ARM Demon monitor support (RDP protocol, "target rdp").
3405 Kernel Object Display, an embedded debugging feature which only worked with
3406 an obsolete version of Cisco IOS.
3408 The 'set download-write-size' and 'show download-write-size' commands.
3410 * New remote packets
3413 Tell a stub about GDB client features, and request remote target features.
3414 The first feature implemented is PacketSize, which allows the target to
3415 specify the size of packets it can handle - to minimize the number of
3416 packets required and improve performance when connected to a remote
3420 Fetch an OS auxilliary vector from the remote stub. This packet is a
3421 more efficient replacement for qPart:auxv:read.
3423 qXfer:memory-map:read:
3424 Fetch a memory map from the remote stub, including information about
3425 RAM, ROM, and flash memory devices.
3430 Erase and program a flash memory device.
3432 * Removed remote packets
3435 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3436 used it, and only gdbserver implemented it.
3438 *** Changes in GDB 6.5
3442 Renesas M32C/M16C m32c-elf
3444 Morpho Technologies ms1 ms1-elf
3448 init-if-undefined Initialize a convenience variable, but
3449 only if it doesn't already have a value.
3451 The following commands are presently only implemented for native GNU/Linux:
3453 checkpoint Save a snapshot of the program state.
3455 restart <n> Return the program state to a
3456 previously saved state.
3458 info checkpoints List currently saved checkpoints.
3460 delete-checkpoint <n> Delete a previously saved checkpoint.
3462 set|show detach-on-fork Tell gdb whether to detach from a newly
3463 forked process, or to keep debugging it.
3465 info forks List forks of the user program that
3466 are available to be debugged.
3468 fork <n> Switch to debugging one of several
3469 forks of the user program that are
3470 available to be debugged.
3472 delete-fork <n> Delete a fork from the list of forks
3473 that are available to be debugged (and
3474 kill the forked process).
3476 detach-fork <n> Delete a fork from the list of forks
3477 that are available to be debugged (and
3478 allow the process to continue).
3482 Morpho Technologies ms2 ms1-elf
3484 * Improved Windows host support
3486 GDB now builds as a cross debugger hosted on i686-mingw32, including
3487 native console support, and remote communications using either
3488 network sockets or serial ports.
3490 * Improved Modula-2 language support
3492 GDB can now print most types in the Modula-2 syntax. This includes:
3493 basic types, set types, record types, enumerated types, range types,
3494 pointer types and ARRAY types. Procedure var parameters are correctly
3495 printed and hexadecimal addresses and character constants are also
3496 written in the Modula-2 syntax. Best results can be obtained by using
3497 GNU Modula-2 together with the -gdwarf-2 command line option.
3501 The ARM rdi-share module.
3503 The Netware NLM debug server.
3505 *** Changes in GDB 6.4
3507 * New native configurations
3509 OpenBSD/arm arm*-*-openbsd*
3510 OpenBSD/mips64 mips64-*-openbsd*
3514 Morpho Technologies ms1 ms1-elf
3516 * New command line options
3518 --batch-silent As for --batch, but totally silent.
3519 --return-child-result The debugger will exist with the same value
3520 the child (debugged) program exited with.
3521 --eval-command COMMAND, -ex COMMAND
3522 Execute a single GDB CLI command. This may be
3523 specified multiple times and in conjunction
3524 with the --command (-x) option.
3526 * Deprecated commands removed
3528 The following commands, that were deprecated in 2000, have been
3532 set|show arm disassembly-flavor set|show arm disassembler
3533 othernames set arm disassembler
3534 set|show remotedebug set|show debug remote
3535 set|show archdebug set|show debug arch
3536 set|show eventdebug set|show debug event
3539 * New BSD user-level threads support
3541 It is now possible to debug programs using the user-level threads
3542 library on OpenBSD and FreeBSD. Currently supported (target)
3545 FreeBSD/amd64 x86_64-*-freebsd*
3546 FreeBSD/i386 i386-*-freebsd*
3547 OpenBSD/i386 i386-*-openbsd*
3549 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3550 are not yet supported.
3552 * New support for Matsushita MN10300 w/sim added
3553 (Work in progress). mn10300-elf.
3555 * REMOVED configurations and files
3557 VxWorks and the XDR protocol *-*-vxworks
3558 Motorola MCORE mcore-*-*
3559 National Semiconductor NS32000 ns32k-*-*
3561 * New "set print array-indexes" command
3563 After turning this setting "on", GDB prints the index of each element
3564 when displaying arrays. The default is "off" to preserve the previous
3567 * VAX floating point support
3569 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3571 * User-defined command support
3573 In addition to using $arg0..$arg9 for argument passing, it is now possible
3574 to use $argc to determine now many arguments have been passed. See the
3575 section on user-defined commands in the user manual for more information.
3577 *** Changes in GDB 6.3:
3579 * New command line option
3581 GDB now accepts -l followed by a number to set the timeout for remote
3584 * GDB works with GCC -feliminate-dwarf2-dups
3586 GDB now supports a more compact representation of DWARF-2 debug
3587 information using DW_FORM_ref_addr references. These are produced
3588 by GCC with the option -feliminate-dwarf2-dups and also by some
3589 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3590 to use -feliminate-dwarf2-dups.
3592 * Internationalization
3594 When supported by the host system, GDB will be built with
3595 internationalization (libintl). The task of marking up the sources is
3596 continued, we're looking forward to our first translation.
3600 Initial support for debugging programs compiled with the GNAT
3601 implementation of the Ada programming language has been integrated
3602 into GDB. In this release, support is limited to expression evaluation.
3604 * New native configurations
3606 GNU/Linux/m32r m32r-*-linux-gnu
3610 GDB's remote protocol now includes support for the 'p' packet. This
3611 packet is used to fetch individual registers from a remote inferior.
3613 * END-OF-LIFE registers[] compatibility module
3615 GDB's internal register infrastructure has been completely rewritten.
3616 The new infrastructure making possible the implementation of key new
3617 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3620 GDB 6.3 will be the last release to include the the registers[]
3621 compatibility module that allowed out-of-date configurations to
3622 continue to work. This change directly impacts the following
3632 powerpc bdm protocol
3634 Unless there is activity to revive these configurations, they will be
3635 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3637 * OBSOLETE configurations and files
3639 Configurations that have been declared obsolete in this release have
3640 been commented out. Unless there is activity to revive these
3641 configurations, the next release of GDB will have their sources
3642 permanently REMOVED.
3651 *** Changes in GDB 6.2.1:
3653 * MIPS `break main; run' gave an heuristic-fence-post warning
3655 When attempting to run even a simple program, a warning about
3656 heuristic-fence-post being hit would be reported. This problem has
3659 * MIPS IRIX 'long double' crashed GDB
3661 When examining a long double variable, GDB would get a segmentation
3662 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3663 IRIX long double values).
3667 A bug in the VAX stack code was causing problems with the "next"
3668 command. This problem has been fixed.
3670 *** Changes in GDB 6.2:
3672 * Fix for ``many threads''
3674 On GNU/Linux systems that use the NPTL threads library, a program
3675 rapidly creating and deleting threads would confuse GDB leading to the
3678 ptrace: No such process.
3679 thread_db_get_info: cannot get thread info: generic error
3681 This problem has been fixed.
3683 * "-async" and "-noasync" options removed.
3685 Support for the broken "-noasync" option has been removed (it caused
3688 * New ``start'' command.
3690 This command runs the program until the begining of the main procedure.
3692 * New BSD Kernel Data Access Library (libkvm) interface
3694 Using ``target kvm'' it is now possible to debug kernel core dumps and
3695 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3696 platforms. Currently supported (native-only) configurations are:
3698 FreeBSD/amd64 x86_64-*-freebsd*
3699 FreeBSD/i386 i?86-*-freebsd*
3700 NetBSD/i386 i?86-*-netbsd*
3701 NetBSD/m68k m68*-*-netbsd*
3702 NetBSD/sparc sparc-*-netbsd*
3703 OpenBSD/amd64 x86_64-*-openbsd*
3704 OpenBSD/i386 i?86-*-openbsd*
3705 OpenBSD/m68k m68*-openbsd*
3706 OpenBSD/sparc sparc-*-openbsd*
3708 * Signal trampoline code overhauled
3710 Many generic problems with GDB's signal handling code have been fixed.
3711 These include: backtraces through non-contiguous stacks; recognition
3712 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3713 call; backtrace through a signal trampoline; step into and out of
3714 signal handlers; and single-stepping in the signal trampoline.
3716 Please note that kernel bugs are a limiting factor here. These
3717 features have been shown to work on an s390 GNU/Linux system that
3718 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3720 * Cygwin support for DWARF 2 added.
3722 * New native configurations
3724 GNU/Linux/hppa hppa*-*-linux*
3725 OpenBSD/hppa hppa*-*-openbsd*
3726 OpenBSD/m68k m68*-*-openbsd*
3727 OpenBSD/m88k m88*-*-openbsd*
3728 OpenBSD/powerpc powerpc-*-openbsd*
3729 NetBSD/vax vax-*-netbsd*
3730 OpenBSD/vax vax-*-openbsd*
3732 * END-OF-LIFE frame compatibility module
3734 GDB's internal frame infrastructure has been completely rewritten.
3735 The new infrastructure making it possible to support key new features
3736 including DWARF 2 Call Frame Information. To aid in the task of
3737 migrating old configurations to this new infrastructure, a
3738 compatibility module, that allowed old configurations to continue to
3739 work, was also included.
3741 GDB 6.2 will be the last release to include this frame compatibility
3742 module. This change directly impacts the following configurations:
3752 Unless there is activity to revive these configurations, they will be
3753 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3755 * REMOVED configurations and files
3757 Sun 3, running SunOS 3 m68*-*-sunos3*
3758 Sun 3, running SunOS 4 m68*-*-sunos4*
3759 Sun 2, running SunOS 3 m68000-*-sunos3*
3760 Sun 2, running SunOS 4 m68000-*-sunos4*
3761 Motorola 680x0 running LynxOS m68*-*-lynxos*
3762 AT&T 3b1/Unix pc m68*-att-*
3763 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3764 decstation mips-dec-* mips-little-*
3765 riscos mips-*-riscos* mips-*-sysv*
3766 sonymips mips-sony-*
3767 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3769 *** Changes in GDB 6.1.1:
3771 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3773 The TUI (Text-mode User Interface) is now built as part of a default
3774 GDB configuration. It is enabled by either selecting the TUI with the
3775 command line option "-i=tui" or by running the separate "gdbtui"
3776 program. For more information on the TUI, see the manual "Debugging
3779 * Pending breakpoint support (also included in GDB 6.1)
3781 Support has been added to allow you to specify breakpoints in shared
3782 libraries that have not yet been loaded. If a breakpoint location
3783 cannot be found, and the "breakpoint pending" option is set to auto,
3784 GDB queries you if you wish to make the breakpoint pending on a future
3785 shared-library load. If and when GDB resolves the breakpoint symbol,
3786 the pending breakpoint is removed as one or more regular breakpoints
3789 Pending breakpoints are very useful for GCJ Java debugging.
3791 * Fixed ISO-C build problems
3793 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3794 non ISO-C code that stopped them being built using a more strict ISO-C
3795 compiler (e.g., IBM's C compiler).
3797 * Fixed build problem on IRIX 5
3799 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3800 wasn't able to compile compile on an IRIX 5 system.
3802 * Added execute permission to gdb/gdbserver/configure
3804 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3805 permission. This bug would cause configure to fail on a number of
3806 systems (Solaris, IRIX). Ref: server/519.
3808 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3810 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3811 has been updated to use constant array sizes.
3813 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3815 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3816 its generated DWARF Call Frame Info. This encoding was causing GDB to
3817 panic, that panic has been fixed. Ref: gdb/1628.
3819 * Fixed a problem when examining parameters in shared library code.
3821 When examining parameters in optimized shared library code generated
3822 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3823 not available''. GDB now correctly displays the variable's value.
3825 *** Changes in GDB 6.1:
3827 * Removed --with-mmalloc
3829 Support for the mmalloc memory manager has been removed, as it
3830 conflicted with the internal gdb byte cache.
3832 * Changes in AMD64 configurations
3834 The AMD64 target now includes the %cs and %ss registers. As a result
3835 the AMD64 remote protocol has changed; this affects the floating-point
3836 and SSE registers. If you rely on those registers for your debugging,
3837 you should upgrade gdbserver on the remote side.
3839 * Revised SPARC target
3841 The SPARC target has been completely revised, incorporating the
3842 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3843 support for LynxOS and SunOS 4 has been dropped. Calling functions
3844 from within GDB on operating systems with a non-executable stack
3845 (Solaris, OpenBSD) now works.
3849 GDB has a new C++ demangler which does a better job on the mangled
3850 names generated by current versions of g++. It also runs faster, so
3851 with this and other changes gdb should now start faster on large C++
3854 * DWARF 2 Location Expressions
3856 GDB support for location expressions has been extended to support function
3857 arguments and frame bases. Older versions of GDB could crash when they
3860 * C++ nested types and namespaces
3862 GDB's support for nested types and namespaces in C++ has been
3863 improved, especially if you use the DWARF 2 debugging format. (This
3864 is the default for recent versions of GCC on most platforms.)
3865 Specifically, if you have a class "Inner" defined within a class or
3866 namespace "Outer", then GDB realizes that the class's name is
3867 "Outer::Inner", not simply "Inner". This should greatly reduce the
3868 frequency of complaints about not finding RTTI symbols. In addition,
3869 if you are stopped at inside of a function defined within a namespace,
3870 GDB modifies its name lookup accordingly.
3872 * New native configurations
3874 NetBSD/amd64 x86_64-*-netbsd*
3875 OpenBSD/amd64 x86_64-*-openbsd*
3876 OpenBSD/alpha alpha*-*-openbsd*
3877 OpenBSD/sparc sparc-*-openbsd*
3878 OpenBSD/sparc64 sparc64-*-openbsd*
3880 * New debugging protocols
3882 M32R with SDI protocol m32r-*-elf*
3884 * "set prompt-escape-char" command deleted.
3886 The command "set prompt-escape-char" has been deleted. This command,
3887 and its very obscure effet on GDB's prompt, was never documented,
3888 tested, nor mentioned in the NEWS file.
3890 * OBSOLETE configurations and files
3892 Configurations that have been declared obsolete in this release have
3893 been commented out. Unless there is activity to revive these
3894 configurations, the next release of GDB will have their sources
3895 permanently REMOVED.
3897 Sun 3, running SunOS 3 m68*-*-sunos3*
3898 Sun 3, running SunOS 4 m68*-*-sunos4*
3899 Sun 2, running SunOS 3 m68000-*-sunos3*
3900 Sun 2, running SunOS 4 m68000-*-sunos4*
3901 Motorola 680x0 running LynxOS m68*-*-lynxos*
3902 AT&T 3b1/Unix pc m68*-att-*
3903 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3904 decstation mips-dec-* mips-little-*
3905 riscos mips-*-riscos* mips-*-sysv*
3906 sonymips mips-sony-*
3907 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3909 * REMOVED configurations and files
3911 SGI Irix-4.x mips-sgi-irix4 or iris4
3912 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3913 Z8000 simulator z8k-zilog-none or z8ksim
3914 Matsushita MN10200 w/simulator mn10200-*-*
3915 H8/500 simulator h8500-hitachi-hms or h8500hms
3916 HP/PA running BSD hppa*-*-bsd*
3917 HP/PA running OSF/1 hppa*-*-osf*
3918 HP/PA Pro target hppa*-*-pro*
3919 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3920 386BSD i[3456]86-*-bsd*
3921 Sequent family i[3456]86-sequent-sysv4*
3922 i[3456]86-sequent-sysv*
3923 i[3456]86-sequent-bsd*
3924 SPARC running LynxOS sparc-*-lynxos*
3925 SPARC running SunOS 4 sparc-*-sunos4*
3926 Tsqware Sparclet sparclet-*-*
3927 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3929 *** Changes in GDB 6.0:
3933 Support for debugging the Objective-C programming language has been
3934 integrated into GDB.
3936 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3938 DWARF 2's Call Frame Information makes available compiler generated
3939 information that more exactly describes the program's run-time stack.
3940 By using this information, GDB is able to provide more robust stack
3943 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3944 have been updated to use a new backtrace mechanism which includes
3945 DWARF 2 CFI support.
3949 GDB's remote protocol has been extended to include support for hosted
3950 file I/O (where the remote target uses GDB's file system). See GDB's
3951 remote protocol documentation for details.
3953 * All targets using the new architecture framework.
3955 All of GDB's targets have been updated to use the new internal
3956 architecture framework. The way is now open for future GDB releases
3957 to include cross-architecture native debugging support (i386 on amd64,
3960 * GNU/Linux's Thread Local Storage (TLS)
3962 GDB now includes support for for the GNU/Linux implementation of
3963 per-thread variables.
3965 * GNU/Linux's Native POSIX Thread Library (NPTL)
3967 GDB's thread code has been updated to work with either the new
3968 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3970 * Separate debug info.
3972 GDB, in conjunction with BINUTILS, now supports a mechanism for
3973 automatically loading debug information from a separate file. Instead
3974 of shipping full debug and non-debug versions of system libraries,
3975 system integrators can now instead ship just the stripped libraries
3976 and optional debug files.
3978 * DWARF 2 Location Expressions
3980 DWARF 2 Location Expressions allow the compiler to more completely
3981 describe the location of variables (even in optimized code) to the
3984 GDB now includes preliminary support for location expressions (support
3985 for DW_OP_piece is still missing).
3989 A number of long standing bugs that caused GDB to die while starting a
3990 Java application have been fixed. GDB's Java support is now
3991 considered "useable".
3993 * GNU/Linux support for fork, vfork, and exec.
3995 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3996 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3999 * GDB supports logging output to a file
4001 There are two new commands, "set logging" and "show logging", which can be
4002 used to capture GDB's output to a file.
4004 * The meaning of "detach" has changed for gdbserver
4006 The "detach" command will now resume the application, as documented. To
4007 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4010 * d10v, m68hc11 `regs' command deprecated
4012 The `info registers' command has been updated so that it displays the
4013 registers using a format identical to the old `regs' command.
4017 A new command, "maint set profile on/off", has been added. This command can
4018 be used to enable or disable profiling while running GDB, to profile a
4019 session or a set of commands. In addition there is a new configure switch,
4020 "--enable-profiling", which will cause GDB to be compiled with profiling
4021 data, for more informative profiling results.
4023 * Default MI syntax changed to "mi2".
4025 The default MI (machine interface) syntax, enabled by the command line
4026 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4027 "mi1", can be enabled by specifying the option "-i=mi1".
4029 Support for the original "mi0" syntax (included in GDB 5.0) has been
4032 Fix for gdb/192: removed extraneous space when displaying frame level.
4033 Fix for gdb/672: update changelist is now output in mi list format.
4034 Fix for gdb/702: a -var-assign that updates the value now shows up
4035 in a subsequent -var-update.
4037 * New native configurations.
4039 FreeBSD/amd64 x86_64-*-freebsd*
4041 * Multi-arched targets.
4043 HP/PA HPUX11 hppa*-*-hpux*
4044 Renesas M32R/D w/simulator m32r-*-elf*
4046 * OBSOLETE configurations and files
4048 Configurations that have been declared obsolete in this release have
4049 been commented out. Unless there is activity to revive these
4050 configurations, the next release of GDB will have their sources
4051 permanently REMOVED.
4053 Z8000 simulator z8k-zilog-none or z8ksim
4054 Matsushita MN10200 w/simulator mn10200-*-*
4055 H8/500 simulator h8500-hitachi-hms or h8500hms
4056 HP/PA running BSD hppa*-*-bsd*
4057 HP/PA running OSF/1 hppa*-*-osf*
4058 HP/PA Pro target hppa*-*-pro*
4059 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4060 Sequent family i[3456]86-sequent-sysv4*
4061 i[3456]86-sequent-sysv*
4062 i[3456]86-sequent-bsd*
4063 Tsqware Sparclet sparclet-*-*
4064 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4066 * REMOVED configurations and files
4069 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4070 IBM AIX PS/2 i[3456]86-*-aix
4071 i386 running Mach 3.0 i[3456]86-*-mach3*
4072 i386 running Mach i[3456]86-*-mach*
4073 i386 running OSF/1 i[3456]86-*osf1mk*
4074 HP/Apollo 68k Family m68*-apollo*-sysv*,
4076 m68*-hp-bsd*, m68*-hp-hpux*
4077 Argonaut Risc Chip (ARC) arc-*-*
4078 Mitsubishi D30V d30v-*-*
4079 Fujitsu FR30 fr30-*-elf*
4080 OS/9000 i[34]86-*-os9k
4081 I960 with MON960 i960-*-coff
4083 * MIPS $fp behavior changed
4085 The convenience variable $fp, for the MIPS, now consistently returns
4086 the address of the current frame's base. Previously, depending on the
4087 context, $fp could refer to either $sp or the current frame's base
4088 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4089 The GNU Source-Level Debugger''.
4091 *** Changes in GDB 5.3:
4093 * GNU/Linux shared library multi-threaded performance improved.
4095 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4096 `/proc', in preference to `ptrace' for memory reads. This may result
4097 in an improvement in the start-up time of multi-threaded, shared
4098 library applications when run under GDB. One GDB user writes: ``loads
4099 shared libs like mad''.
4101 * ``gdbserver'' now supports multi-threaded applications on some targets
4103 Support for debugging multi-threaded applications which use
4104 the GNU/Linux LinuxThreads package has been added for
4105 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4106 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4108 * GDB now supports C/C++ preprocessor macros.
4110 GDB now expands preprocessor macro invocations in C/C++ expressions,
4111 and provides various commands for showing macro definitions and how
4114 The new command `macro expand EXPRESSION' expands any macro
4115 invocations in expression, and shows the result.
4117 The new command `show macro MACRO-NAME' shows the definition of the
4118 macro named MACRO-NAME, and where it was defined.
4120 Most compilers don't include information about macros in the debugging
4121 information by default. In GCC 3.1, for example, you need to compile
4122 your program with the options `-gdwarf-2 -g3'. If the macro
4123 information is present in the executable, GDB will read it.
4125 * Multi-arched targets.
4127 DEC Alpha (partial) alpha*-*-*
4128 DEC VAX (partial) vax-*-*
4130 National Semiconductor NS32000 (partial) ns32k-*-*
4131 Motorola 68000 (partial) m68k-*-*
4132 Motorola MCORE mcore-*-*
4136 Fujitsu FRV architecture added by Red Hat frv*-*-*
4139 * New native configurations
4141 Alpha NetBSD alpha*-*-netbsd*
4142 SH NetBSD sh*-*-netbsdelf*
4143 MIPS NetBSD mips*-*-netbsd*
4144 UltraSPARC NetBSD sparc64-*-netbsd*
4146 * OBSOLETE configurations and files
4148 Configurations that have been declared obsolete in this release have
4149 been commented out. Unless there is activity to revive these
4150 configurations, the next release of GDB will have their sources
4151 permanently REMOVED.
4153 Mitsubishi D30V d30v-*-*
4154 OS/9000 i[34]86-*-os9k
4155 IBM AIX PS/2 i[3456]86-*-aix
4156 Fujitsu FR30 fr30-*-elf*
4157 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4158 Argonaut Risc Chip (ARC) arc-*-*
4159 i386 running Mach 3.0 i[3456]86-*-mach3*
4160 i386 running Mach i[3456]86-*-mach*
4161 i386 running OSF/1 i[3456]86-*osf1mk*
4162 HP/Apollo 68k Family m68*-apollo*-sysv*,
4164 m68*-hp-bsd*, m68*-hp-hpux*
4165 I960 with MON960 i960-*-coff
4167 * OBSOLETE languages
4169 CHILL, a Pascal like language used by telecommunications companies.
4171 * REMOVED configurations and files
4173 AMD 29k family via UDI a29k-amd-udi, udi29k
4174 A29K VxWorks a29k-*-vxworks
4175 AMD 29000 embedded, using EBMON a29k-none-none
4176 AMD 29000 embedded with COFF a29k-none-coff
4177 AMD 29000 embedded with a.out a29k-none-aout
4179 testsuite/gdb.hp/gdb.threads-hp/ directory
4181 * New command "set max-user-call-depth <nnn>"
4183 This command allows the user to limit the call depth of user-defined
4184 commands. The default is 1024.
4186 * Changes in FreeBSD/i386 native debugging.
4188 Support for the "generate-core-file" has been added.
4190 * New commands "dump", "append", and "restore".
4192 These commands allow data to be copied from target memory
4193 to a bfd-format or binary file (dump and append), and back
4194 from a file into memory (restore).
4196 * Improved "next/step" support on multi-processor Alpha Tru64.
4198 The previous single-step mechanism could cause unpredictable problems,
4199 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4200 of a software single-step mechanism prevents this.
4202 *** Changes in GDB 5.2.1:
4210 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4211 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4212 Fix, by Joel Brobecker imported from mainline.
4214 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4215 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4216 Fix, by Fred Fish, imported from mainline.
4218 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4219 Surprisingly enough, it works now.
4220 By Michal Ludvig, imported from mainline.
4222 i386 hardware watchpoint support:
4223 avoid misses on second run for some targets.
4224 By Pierre Muller, imported from mainline.
4226 *** Changes in GDB 5.2:
4228 * New command "set trust-readonly-sections on[off]".
4230 This command is a hint that tells gdb that read-only sections
4231 really are read-only (ie. that their contents will not change).
4232 In this mode, gdb will go to the object file rather than the
4233 target to read memory from read-only sections (such as ".text").
4234 This can be a significant performance improvement on some
4235 (notably embedded) targets.
4237 * New command "generate-core-file" (or "gcore").
4239 This new gdb command allows the user to drop a core file of the child
4240 process state at any time. So far it's been implemented only for
4241 GNU/Linux and Solaris, but should be relatively easily ported to other
4242 hosts. Argument is core file name (defaults to core.<pid>).
4244 * New command line option
4246 GDB now accepts --pid or -p followed by a process id.
4248 * Change in command line behavior -- corefiles vs. process ids.
4250 There is a subtle behavior in the way in which GDB handles
4251 command line arguments. The first non-flag argument is always
4252 a program to debug, but the second non-flag argument may either
4253 be a corefile or a process id. Previously, GDB would attempt to
4254 open the second argument as a corefile, and if that failed, would
4255 issue a superfluous error message and then attempt to attach it as
4256 a process. Now, if the second argument begins with a non-digit,
4257 it will be treated as a corefile. If it begins with a digit,
4258 GDB will attempt to attach it as a process, and if no such process
4259 is found, will then attempt to open it as a corefile.
4261 * Changes in ARM configurations.
4263 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4264 configuration is fully multi-arch.
4266 * New native configurations
4268 ARM NetBSD arm*-*-netbsd*
4269 x86 OpenBSD i[3456]86-*-openbsd*
4270 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4271 Sparc64 running FreeBSD sparc64-*-freebsd*
4275 Sanyo XStormy16 xstormy16-elf
4277 * OBSOLETE configurations and files
4279 Configurations that have been declared obsolete in this release have
4280 been commented out. Unless there is activity to revive these
4281 configurations, the next release of GDB will have their sources
4282 permanently REMOVED.
4284 AMD 29k family via UDI a29k-amd-udi, udi29k
4285 A29K VxWorks a29k-*-vxworks
4286 AMD 29000 embedded, using EBMON a29k-none-none
4287 AMD 29000 embedded with COFF a29k-none-coff
4288 AMD 29000 embedded with a.out a29k-none-aout
4290 testsuite/gdb.hp/gdb.threads-hp/ directory
4292 * REMOVED configurations and files
4294 TI TMS320C80 tic80-*-*
4296 PowerPC Solaris powerpcle-*-solaris*
4297 PowerPC Windows NT powerpcle-*-cygwin32
4298 PowerPC Netware powerpc-*-netware*
4299 Harris/CXUX m88k m88*-harris-cxux*
4300 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4301 ns32k-utek-sysv* ns32k-utek-*
4302 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4303 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4304 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4305 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4306 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4308 * Changes to command line processing
4310 The new `--args' feature can be used to specify command-line arguments
4311 for the inferior from gdb's command line.
4313 * Changes to key bindings
4315 There is a new `operate-and-get-next' function bound to `C-o'.
4317 *** Changes in GDB 5.1.1
4319 Fix compile problem on DJGPP.
4321 Fix a problem with floating-point registers on the i386 being
4324 Fix to stop GDB crashing on .debug_str debug info.
4326 Numerous documentation fixes.
4328 Numerous testsuite fixes.
4330 *** Changes in GDB 5.1:
4332 * New native configurations
4334 Alpha FreeBSD alpha*-*-freebsd*
4335 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4336 MIPS GNU/Linux mips*-*-linux*
4337 MIPS SGI Irix 6.x mips*-sgi-irix6*
4338 ia64 AIX ia64-*-aix*
4339 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4343 Motorola 68HC11 and 68HC12 m68hc11-elf
4345 UltraSparc running GNU/Linux sparc64-*-linux*
4347 * OBSOLETE configurations and files
4349 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4350 Harris/CXUX m88k m88*-harris-cxux*
4351 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4352 ns32k-utek-sysv* ns32k-utek-*
4353 TI TMS320C80 tic80-*-*
4355 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4356 PowerPC Solaris powerpcle-*-solaris*
4357 PowerPC Windows NT powerpcle-*-cygwin32
4358 PowerPC Netware powerpc-*-netware*
4359 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4360 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4361 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4362 Apple Macintosh (MPW) host N/A
4364 stuff.c (Program to stuff files into a specially prepared space in kdb)
4365 kdb-start.c (Main loop for the standalone kernel debugger)
4367 Configurations that have been declared obsolete in this release have
4368 been commented out. Unless there is activity to revive these
4369 configurations, the next release of GDB will have their sources
4370 permanently REMOVED.
4372 * REMOVED configurations and files
4374 Altos 3068 m68*-altos-*
4375 Convex c1-*-*, c2-*-*
4377 ARM RISCix arm-*-* (as host)
4381 * GDB has been converted to ISO C.
4383 GDB's source code has been converted to ISO C. In particular, the
4384 sources are fully protoized, and rely on standard headers being
4389 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4391 * The MI enabled by default.
4393 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4394 revised and enabled by default. Packages which use GDB as a debugging
4395 engine behind a UI or another front end are encouraged to switch to
4396 using the GDB/MI interface, instead of the old annotations interface
4397 which is now deprecated.
4399 * Support for debugging Pascal programs.
4401 GDB now includes support for debugging Pascal programs. The following
4402 main features are supported:
4404 - Pascal-specific data types such as sets;
4406 - automatic recognition of Pascal sources based on file-name
4409 - Pascal-style display of data types, variables, and functions;
4411 - a Pascal expression parser.
4413 However, some important features are not yet supported.
4415 - Pascal string operations are not supported at all;
4417 - there are some problems with boolean types;
4419 - Pascal type hexadecimal constants are not supported
4420 because they conflict with the internal variables format;
4422 - support for Pascal objects and classes is not full yet;
4424 - unlike Pascal, GDB is case-sensitive for symbol names.
4426 * Changes in completion.
4428 Commands such as `shell', `run' and `set args', which pass arguments
4429 to inferior programs, now complete on file names, similar to what
4430 users expect at the shell prompt.
4432 Commands which accept locations, such as `disassemble', `print',
4433 `breakpoint', `until', etc. now complete on filenames as well as
4434 program symbols. Thus, if you type "break foob TAB", and the source
4435 files linked into the programs include `foobar.c', that file name will
4436 be one of the candidates for completion. However, file names are not
4437 considered for completion after you typed a colon that delimits a file
4438 name from a name of a function in that file, as in "break foo.c:bar".
4440 `set demangle-style' completes on available demangling styles.
4442 * New platform-independent commands:
4444 It is now possible to define a post-hook for a command as well as a
4445 hook that runs before the command. For more details, see the
4446 documentation of `hookpost' in the GDB manual.
4448 * Changes in GNU/Linux native debugging.
4450 Support for debugging multi-threaded programs has been completely
4451 revised for all platforms except m68k and sparc. You can now debug as
4452 many threads as your system allows you to have.
4454 Attach/detach is supported for multi-threaded programs.
4456 Support for SSE registers was added for x86. This doesn't work for
4457 multi-threaded programs though.
4459 * Changes in MIPS configurations.
4461 Multi-arch support is enabled for all MIPS configurations.
4463 GDB can now be built as native debugger on SGI Irix 6.x systems for
4464 debugging n32 executables. (Debugging 64-bit executables is not yet
4467 * Unified support for hardware watchpoints in all x86 configurations.
4469 Most (if not all) native x86 configurations support hardware-assisted
4470 breakpoints and watchpoints in a unified manner. This support
4471 implements debug register sharing between watchpoints, which allows to
4472 put a virtually infinite number of watchpoints on the same address,
4473 and also supports watching regions up to 16 bytes with several debug
4476 The new maintenance command `maintenance show-debug-regs' toggles
4477 debugging print-outs in functions that insert, remove, and test
4478 watchpoints and hardware breakpoints.
4480 * Changes in the DJGPP native configuration.
4482 New command ``info dos sysinfo'' displays assorted information about
4483 the CPU, OS, memory, and DPMI server.
4485 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4486 display information about segment descriptors stored in GDT, LDT, and
4489 New commands ``info dos pde'' and ``info dos pte'' display entries
4490 from Page Directory and Page Tables (for now works with CWSDPMI only).
4491 New command ``info dos address-pte'' displays the Page Table entry for
4492 a given linear address.
4494 GDB can now pass command lines longer than 126 characters to the
4495 program being debugged (requires an update to the libdbg.a library
4496 which is part of the DJGPP development kit).
4498 DWARF2 debug info is now supported.
4500 It is now possible to `step' and `next' through calls to `longjmp'.
4502 * Changes in documentation.
4504 All GDB documentation was converted to GFDL, the GNU Free
4505 Documentation License.
4507 Tracepoints-related commands are now fully documented in the GDB
4510 TUI, the Text-mode User Interface, is now documented in the manual.
4512 Tracepoints-related commands are now fully documented in the GDB
4515 The "GDB Internals" manual now has an index. It also includes
4516 documentation of `ui_out' functions, GDB coding standards, x86
4517 hardware watchpoints, and memory region attributes.
4519 * GDB's version number moved to ``version.in''
4521 The Makefile variable VERSION has been replaced by the file
4522 ``version.in''. People creating GDB distributions should update the
4523 contents of this file.
4527 GUD support is now a standard part of the EMACS distribution.
4529 *** Changes in GDB 5.0:
4531 * Improved support for debugging FP programs on x86 targets
4533 Unified and much-improved support for debugging floating-point
4534 programs on all x86 targets. In particular, ``info float'' now
4535 displays the FP registers in the same format on all x86 targets, with
4536 greater level of detail.
4538 * Improvements and bugfixes in hardware-assisted watchpoints
4540 It is now possible to watch array elements, struct members, and
4541 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4542 on x86 targets no longer erroneously trigger when the address is
4545 * Improvements in the native DJGPP version of GDB
4547 The distribution now includes all the scripts and auxiliary files
4548 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4549 machines ``out of the box''.
4551 The DJGPP version can now debug programs that use signals. It is
4552 possible to catch signals that happened in the debuggee, deliver
4553 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4554 would kill the program being debugged.) Programs that hook hardware
4555 interrupts (keyboard, timer, etc.) can also be debugged.
4557 It is now possible to debug DJGPP programs that redirect their
4558 standard handles or switch them to raw (as opposed to cooked) mode, or
4559 even close them. The command ``run < foo > bar'' works as expected,
4560 and ``info terminal'' reports useful information about the debuggee's
4561 terminal, including raw/cooked mode, redirection, etc.
4563 The DJGPP version now uses termios functions for console I/O, which
4564 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4567 DOS-style file names with drive letters are now fully supported by
4570 It is now possible to debug DJGPP programs that switch their working
4571 directory. It is also possible to rerun the debuggee any number of
4572 times without restarting GDB; thus, you can use the same setup,
4573 breakpoints, etc. for many debugging sessions.
4575 * New native configurations
4577 ARM GNU/Linux arm*-*-linux*
4578 PowerPC GNU/Linux powerpc-*-linux*
4582 Motorola MCore mcore-*-*
4583 x86 VxWorks i[3456]86-*-vxworks*
4584 PowerPC VxWorks powerpc-*-vxworks*
4585 TI TMS320C80 tic80-*-*
4587 * OBSOLETE configurations
4589 Altos 3068 m68*-altos-*
4590 Convex c1-*-*, c2-*-*
4592 ARM RISCix arm-*-* (as host)
4595 Configurations that have been declared obsolete will be commented out,
4596 but the code will be left in place. If there is no activity to revive
4597 these configurations before the next release of GDB, the sources will
4598 be permanently REMOVED.
4600 * Gould support removed
4602 Support for the Gould PowerNode and NP1 has been removed.
4604 * New features for SVR4
4606 On SVR4 native platforms (such as Solaris), if you attach to a process
4607 without first loading a symbol file, GDB will now attempt to locate and
4608 load symbols from the running process's executable file.
4610 * Many C++ enhancements
4612 C++ support has been greatly improved. Overload resolution now works properly
4613 in almost all cases. RTTI support is on the way.
4615 * Remote targets can connect to a sub-program
4617 A popen(3) style serial-device has been added. This device starts a
4618 sub-process (such as a stand-alone simulator) and then communicates
4619 with that. The sub-program to run is specified using the syntax
4620 ``|<program> <args>'' vis:
4622 (gdb) set remotedebug 1
4623 (gdb) target extended-remote |mn10300-elf-sim program-args
4625 * MIPS 64 remote protocol
4627 A long standing bug in the mips64 remote protocol where by GDB
4628 expected certain 32 bit registers (ex SR) to be transfered as 32
4629 instead of 64 bits has been fixed.
4631 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4632 added to provide backward compatibility with older versions of GDB.
4634 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4636 The command ``set remotebinarydownload'' command has been replaced by
4637 ``set remote X-packet''. Other commands in ``set remote'' family
4638 include ``set remote P-packet''.
4640 * Breakpoint commands accept ranges.
4642 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4643 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4644 ``tracepoint passcount'' also accepts a range of tracepoints.
4646 * ``apropos'' command added.
4648 The ``apropos'' command searches through command names and
4649 documentation strings, printing out matches, making it much easier to
4650 try to find a command that does what you are looking for.
4654 A new machine oriented interface (MI) has been added to GDB. This
4655 interface is designed for debug environments running GDB as a separate
4656 process. This is part of the long term libGDB project. See the
4657 "GDB/MI" chapter of the GDB manual for further information. It can be
4658 enabled by configuring with:
4660 .../configure --enable-gdbmi
4662 *** Changes in GDB-4.18:
4664 * New native configurations
4666 HP-UX 10.20 hppa*-*-hpux10.20
4667 HP-UX 11.x hppa*-*-hpux11.0*
4668 M68K GNU/Linux m68*-*-linux*
4672 Fujitsu FR30 fr30-*-elf*
4673 Intel StrongARM strongarm-*-*
4674 Mitsubishi D30V d30v-*-*
4676 * OBSOLETE configurations
4678 Gould PowerNode, NP1 np1-*-*, pn-*-*
4680 Configurations that have been declared obsolete will be commented out,
4681 but the code will be left in place. If there is no activity to revive
4682 these configurations before the next release of GDB, the sources will
4683 be permanently REMOVED.
4687 As a compatibility experiment, GDB's source files buildsym.h and
4688 buildsym.c have been converted to pure standard C, no longer
4689 containing any K&R compatibility code. We believe that all systems in
4690 use today either come with a standard C compiler, or have a GCC port
4691 available. If this is not true, please report the affected
4692 configuration to bug-gdb@gnu.org immediately. See the README file for
4693 information about getting a standard C compiler if you don't have one
4698 GDB now uses readline 2.2.
4700 * set extension-language
4702 You can now control the mapping between filename extensions and source
4703 languages by using the `set extension-language' command. For instance,
4704 you can ask GDB to treat .c files as C++ by saying
4705 set extension-language .c c++
4706 The command `info extensions' lists all of the recognized extensions
4707 and their associated languages.
4709 * Setting processor type for PowerPC and RS/6000
4711 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4712 you can use the `set processor' command to specify what variant of the
4713 PowerPC family you are debugging. The command
4717 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4718 following PowerPC and RS6000 variants:
4720 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4721 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4723 403GC IBM PowerPC 403GC
4724 505 Motorola PowerPC 505
4725 860 Motorola PowerPC 860 or 850
4726 601 Motorola PowerPC 601
4727 602 Motorola PowerPC 602
4728 603 Motorola/IBM PowerPC 603 or 603e
4729 604 Motorola PowerPC 604 or 604e
4730 750 Motorola/IBM PowerPC 750 or 750
4732 At the moment, this command just tells GDB what to name the
4733 special-purpose processor registers. Since almost all the affected
4734 registers are inaccessible to user-level programs, this command is
4735 only useful for remote debugging in its present form.
4739 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4740 more extensive support for HP-UX. Added features include shared
4741 library support, kernel threads and hardware watchpoints for 11.00,
4742 support for HP's ANSI C and C++ compilers, and a compatibility mode
4743 for xdb and dbx commands.
4747 HP's donation includes the new concept of catchpoints, which is a
4748 generalization of the old catch command. On HP-UX, it is now possible
4749 to catch exec, fork, and vfork, as well as library loading.
4751 This means that the existing catch command has changed; its first
4752 argument now specifies the type of catch to be set up. See the
4753 output of "help catch" for a list of catchpoint types.
4755 * Debugging across forks
4757 On HP-UX, you can choose which process to debug when a fork() happens
4762 HP has donated a curses-based terminal user interface (TUI). To get
4763 it, build with --enable-tui. Although this can be enabled for any
4764 configuration, at present it only works for native HP debugging.
4766 * GDB remote protocol additions
4768 A new protocol packet 'X' that writes binary data is now available.
4769 Default behavior is to try 'X', then drop back to 'M' if the stub
4770 fails to respond. The settable variable `remotebinarydownload'
4771 allows explicit control over the use of 'X'.
4773 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4774 full 64-bit address. The command
4776 set remoteaddresssize 32
4778 can be used to revert to the old behaviour. For existing remote stubs
4779 the change should not be noticed, as the additional address information
4782 In order to assist in debugging stubs, you may use the maintenance
4783 command `packet' to send any text string to the stub. For instance,
4785 maint packet heythere
4787 sends the packet "$heythere#<checksum>". Note that it is very easy to
4788 disrupt a debugging session by sending the wrong packet at the wrong
4791 The compare-sections command allows you to compare section data on the
4792 target to what is in the executable file without uploading or
4793 downloading, by comparing CRC checksums.
4795 * Tracing can collect general expressions
4797 You may now collect general expressions at tracepoints. This requires
4798 further additions to the target-side stub; see tracepoint.c and
4799 doc/agentexpr.texi for further details.
4801 * mask-address variable for Mips
4803 For Mips targets, you may control the zeroing of the upper 32 bits of
4804 a 64-bit address by entering `set mask-address on'. This is mainly
4805 of interest to users of embedded R4xxx and R5xxx processors.
4807 * Higher serial baud rates
4809 GDB's serial code now allows you to specify baud rates 57600, 115200,
4810 230400, and 460800 baud. (Note that your host system may not be able
4811 to achieve all of these rates.)
4815 The i960 configuration now includes an initial implementation of a
4816 builtin simulator, contributed by Jim Wilson.
4819 *** Changes in GDB-4.17:
4821 * New native configurations
4823 Alpha GNU/Linux alpha*-*-linux*
4824 Unixware 2.x i[3456]86-unixware2*
4825 Irix 6.x mips*-sgi-irix6*
4826 PowerPC GNU/Linux powerpc-*-linux*
4827 PowerPC Solaris powerpcle-*-solaris*
4828 Sparc GNU/Linux sparc-*-linux*
4829 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4833 Argonaut Risc Chip (ARC) arc-*-*
4834 Hitachi H8/300S h8300*-*-*
4835 Matsushita MN10200 w/simulator mn10200-*-*
4836 Matsushita MN10300 w/simulator mn10300-*-*
4837 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4838 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4839 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4840 Mitsubishi D10V w/simulator d10v-*-*
4841 Mitsubishi M32R/D w/simulator m32r-*-elf*
4842 Tsqware Sparclet sparclet-*-*
4843 NEC V850 w/simulator v850-*-*
4845 * New debugging protocols
4847 ARM with RDI protocol arm*-*-*
4848 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4849 DDB and LSI variants of PMON protocol mips*-*-*
4850 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4851 PowerPC with SDS protocol powerpc{,le}-*-eabi
4852 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4856 All configurations can now understand and use the DWARF 2 debugging
4857 format. The choice is automatic, if the symbol file contains DWARF 2
4862 GDB now includes basic Java language support. This support is
4863 only useful with Java compilers that produce native machine code.
4865 * solib-absolute-prefix and solib-search-path
4867 For SunOS and SVR4 shared libraries, you may now set the prefix for
4868 loading absolute shared library symbol files, and the search path for
4869 locating non-absolute shared library symbol files.
4871 * Live range splitting
4873 GDB can now effectively debug code for which GCC has performed live
4874 range splitting as part of its optimization. See gdb/doc/LRS for
4875 more details on the expected format of the stabs information.
4879 GDB's support for the GNU Hurd, including thread debugging, has been
4880 updated to work with current versions of the Hurd.
4884 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4885 instruction set. ARM GDB automatically detects when Thumb
4886 instructions are in use, and adjusts disassembly and backtracing
4891 GDB's MIPS target configurations now handle the MIP16 16-bit
4896 GDB now includes support for overlays; if an executable has been
4897 linked such that multiple sections are based at the same address, GDB
4898 will decide which section to use for symbolic info. You can choose to
4899 control the decision manually, using overlay commands, or implement
4900 additional target-side support and use "overlay load-target" to bring
4901 in the overlay mapping. Do "help overlay" for more detail.
4905 The command "info symbol <address>" displays information about
4906 the symbol at the specified address.
4910 The standard remote protocol now includes an extension that allows
4911 asynchronous collection and display of trace data. This requires
4912 extensive support in the target-side debugging stub. Tracing mode
4913 includes a new interaction mode in GDB and new commands: see the
4914 file tracepoint.c for more details.
4918 Configurations for embedded MIPS now include a simulator contributed
4919 by Cygnus Solutions. The simulator supports the instruction sets
4920 of most MIPS variants.
4924 Sparc configurations may now include the ERC32 simulator contributed
4925 by the European Space Agency. The simulator is not built into
4926 Sparc targets by default; configure with --enable-sim to include it.
4930 For target configurations that may include multiple variants of a
4931 basic architecture (such as MIPS and SH), you may now set the
4932 architecture explicitly. "set arch" sets, "info arch" lists
4933 the possible architectures.
4935 *** Changes in GDB-4.16:
4937 * New native configurations
4939 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4940 M68K NetBSD m68k-*-netbsd*
4941 PowerPC AIX 4.x powerpc-*-aix*
4942 PowerPC MacOS powerpc-*-macos*
4943 PowerPC Windows NT powerpcle-*-cygwin32
4944 RS/6000 AIX 4.x rs6000-*-aix4*
4948 ARM with RDP protocol arm-*-*
4949 I960 with MON960 i960-*-coff
4950 MIPS VxWorks mips*-*-vxworks*
4951 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4952 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4954 Matra Sparclet sparclet-*-*
4958 The powerpc-eabi configuration now includes the PSIM simulator,
4959 contributed by Andrew Cagney, with assistance from Mike Meissner.
4960 PSIM is a very elaborate model of the PowerPC, including not only
4961 basic instruction set execution, but also details of execution unit
4962 performance and I/O hardware. See sim/ppc/README for more details.
4966 GDB now works with Solaris 2.5.
4968 * Windows 95/NT native
4970 GDB will now work as a native debugger on Windows 95 and Windows NT.
4971 To build it from source, you must use the "gnu-win32" environment,
4972 which uses a DLL to emulate enough of Unix to run the GNU tools.
4973 Further information, binaries, and sources are available at
4974 ftp.cygnus.com, under pub/gnu-win32.
4976 * dont-repeat command
4978 If a user-defined command includes the command `dont-repeat', then the
4979 command will not be repeated if the user just types return. This is
4980 useful if the command is time-consuming to run, so that accidental
4981 extra keystrokes don't run the same command many times.
4983 * Send break instead of ^C
4985 The standard remote protocol now includes an option to send a break
4986 rather than a ^C to the target in order to interrupt it. By default,
4987 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4989 * Remote protocol timeout
4991 The standard remote protocol includes a new variable `remotetimeout'
4992 that allows you to set the number of seconds before GDB gives up trying
4993 to read from the target. The default value is 2.
4995 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4997 By default GDB will automatically keep track of objects as they are
4998 loaded and unloaded by the dynamic linker. By using the command `set
4999 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5000 when shared library events occur, thus allowing you to set breakpoints
5001 in shared libraries which are explicitly loaded by the inferior.
5003 Note this feature does not work on hpux8. On hpux9 you must link
5004 /usr/lib/end.o into your program. This feature should work
5005 automatically on hpux10.
5007 * Irix 5.x hardware watchpoint support
5009 Irix 5 configurations now support the use of hardware watchpoints.
5011 * Mips protocol "SYN garbage limit"
5013 When debugging a Mips target using the `target mips' protocol, you
5014 may set the number of characters that GDB will ignore by setting
5015 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5016 every character. The default value is 1050.
5018 * Recording and replaying remote debug sessions
5020 If you set `remotelogfile' to the name of a file, gdb will write to it
5021 a recording of a remote debug session. This recording may then be
5022 replayed back to gdb using "gdbreplay". See gdbserver/README for
5023 details. This is useful when you have a problem with GDB while doing
5024 remote debugging; you can make a recording of the session and send it
5025 to someone else, who can then recreate the problem.
5027 * Speedups for remote debugging
5029 GDB includes speedups for downloading and stepping MIPS systems using
5030 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5031 and more efficient S-record downloading.
5033 * Memory use reductions and statistics collection
5035 GDB now uses less memory and reports statistics about memory usage.
5036 Try the `maint print statistics' command, for example.
5038 *** Changes in GDB-4.15:
5040 * Psymtabs for XCOFF
5042 The symbol reader for AIX GDB now uses partial symbol tables. This
5043 can greatly improve startup time, especially for large executables.
5045 * Remote targets use caching
5047 Remote targets now use a data cache to speed up communication with the
5048 remote side. The data cache could lead to incorrect results because
5049 it doesn't know about volatile variables, thus making it impossible to
5050 debug targets which use memory mapped I/O devices. `set remotecache
5051 off' turns the the data cache off.
5053 * Remote targets may have threads
5055 The standard remote protocol now includes support for multiple threads
5056 in the target system, using new protocol commands 'H' and 'T'. See
5057 gdb/remote.c for details.
5061 If GDB is configured with `--enable-netrom', then it will include
5062 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5063 acts as though it is a bank of ROM on the target board, but you can
5064 write into it over the network. GDB's support consists only of
5065 support for fast loading into the emulated ROM; to debug, you must use
5066 another protocol, such as standard remote protocol. The usual
5067 sequence is something like
5069 target nrom <netrom-hostname>
5071 target remote <netrom-hostname>:1235
5075 GDB now includes support for the Apple Macintosh, as a host only. It
5076 may be run as either an MPW tool or as a standalone application, and
5077 it can debug through the serial port. All the usual GDB commands are
5078 available, but to the target command, you must supply "serial" as the
5079 device type instead of "/dev/ttyXX". See mpw-README in the main
5080 directory for more information on how to build. The MPW configuration
5081 scripts */mpw-config.in support only a few targets, and only the
5082 mips-idt-ecoff target has been tested.
5086 GDB configuration now uses autoconf. This is not user-visible,
5087 but does simplify configuration and building.
5091 GDB now supports hpux10.
5093 *** Changes in GDB-4.14:
5095 * New native configurations
5097 x86 FreeBSD i[345]86-*-freebsd
5098 x86 NetBSD i[345]86-*-netbsd
5099 NS32k NetBSD ns32k-*-netbsd
5100 Sparc NetBSD sparc-*-netbsd
5104 A29K VxWorks a29k-*-vxworks
5105 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5106 CPU32 EST-300 emulator m68*-*-est*
5107 PowerPC ELF powerpc-*-elf
5110 * Alpha OSF/1 support for procfs
5112 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5113 possible to attach to running processes. As the mounting of the /proc
5114 filesystem is optional on the Alpha, GDB automatically determines
5115 the availability of /proc during startup. This can lead to problems
5116 if /proc is unmounted after GDB has been started.
5118 * Arguments to user-defined commands
5120 User commands may accept up to 10 arguments separated by whitespace.
5121 Arguments are accessed within the user command via $arg0..$arg9. A
5124 print $arg0 + $arg1 + $arg2
5126 To execute the command use:
5129 Defines the command "adder" which prints the sum of its three arguments.
5130 Note the arguments are text substitutions, so they may reference variables,
5131 use complex expressions, or even perform inferior function calls.
5133 * New `if' and `while' commands
5135 This makes it possible to write more sophisticated user-defined
5136 commands. Both commands take a single argument, which is the
5137 expression to evaluate, and must be followed by the commands to
5138 execute, one per line, if the expression is nonzero, the list being
5139 terminated by the word `end'. The `if' command list may include an
5140 `else' word, which causes the following commands to be executed only
5141 if the expression is zero.
5143 * Fortran source language mode
5145 GDB now includes partial support for Fortran 77. It will recognize
5146 Fortran programs and can evaluate a subset of Fortran expressions, but
5147 variables and functions may not be handled correctly. GDB will work
5148 with G77, but does not yet know much about symbols emitted by other
5151 * Better HPUX support
5153 Most debugging facilities now work on dynamic executables for HPPAs
5154 running hpux9 or later. You can attach to running dynamically linked
5155 processes, but by default the dynamic libraries will be read-only, so
5156 for instance you won't be able to put breakpoints in them. To change
5157 that behavior do the following before running the program:
5163 This will cause the libraries to be mapped private and read-write.
5164 To revert to the normal behavior, do this:
5170 You cannot set breakpoints or examine data in the library until after
5171 the library is loaded if the function/data symbols do not have
5174 GDB can now also read debug symbols produced by the HP C compiler on
5175 HPPAs (sorry, no C++, Fortran or 68k support).
5177 * Target byte order now dynamically selectable
5179 You can choose which byte order to use with a target system, via the
5180 commands "set endian big" and "set endian little", and you can see the
5181 current setting by using "show endian". You can also give the command
5182 "set endian auto", in which case GDB will use the byte order
5183 associated with the executable. Currently, only embedded MIPS
5184 configurations support dynamic selection of target byte order.
5186 * New DOS host serial code
5188 This version uses DPMI interrupts to handle buffered I/O, so you
5189 no longer need to run asynctsr when debugging boards connected to
5192 *** Changes in GDB-4.13:
5194 * New "complete" command
5196 This lists all the possible completions for the rest of the line, if it
5197 were to be given as a command itself. This is intended for use by emacs.
5199 * Trailing space optional in prompt
5201 "set prompt" no longer adds a space for you after the prompt you set. This
5202 allows you to set a prompt which ends in a space or one that does not.
5204 * Breakpoint hit counts
5206 "info break" now displays a count of the number of times the breakpoint
5207 has been hit. This is especially useful in conjunction with "ignore"; you
5208 can ignore a large number of breakpoint hits, look at the breakpoint info
5209 to see how many times the breakpoint was hit, then run again, ignoring one
5210 less than that number, and this will get you quickly to the last hit of
5213 * Ability to stop printing at NULL character
5215 "set print null-stop" will cause GDB to stop printing the characters of
5216 an array when the first NULL is encountered. This is useful when large
5217 arrays actually contain only short strings.
5219 * Shared library breakpoints
5221 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5222 breakpoints in shared libraries before the executable is run.
5224 * Hardware watchpoints
5226 There is a new hardware breakpoint for the watch command for sparclite
5227 targets. See gdb/sparclite/hw_breakpoint.note.
5229 Hardware watchpoints are also now supported under GNU/Linux.
5233 Annotations have been added. These are for use with graphical interfaces,
5234 and are still experimental. Currently only gdba.el uses these.
5236 * Improved Irix 5 support
5238 GDB now works properly with Irix 5.2.
5240 * Improved HPPA support
5242 GDB now works properly with the latest GCC and GAS.
5244 * New native configurations
5246 Sequent PTX4 i[34]86-sequent-ptx4
5247 HPPA running OSF/1 hppa*-*-osf*
5248 Atari TT running SVR4 m68*-*-sysv4*
5249 RS/6000 LynxOS rs6000-*-lynxos*
5253 OS/9000 i[34]86-*-os9k
5254 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5257 * Hitachi SH7000 and E7000-PC ICE support
5259 There is now support for communicating with the Hitachi E7000-PC ICE.
5260 This is available automatically when GDB is configured for the SH.
5264 As usual, a variety of small fixes and improvements, both generic
5265 and configuration-specific. See the ChangeLog for more detail.
5267 *** Changes in GDB-4.12:
5269 * Irix 5 is now supported
5273 GDB-4.12 on the HPPA has a number of changes which make it unable
5274 to debug the output from the currently released versions of GCC and
5275 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5276 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5277 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5280 *** Changes in GDB-4.11:
5282 * User visible changes:
5286 The "set remotedebug" option is now consistent between the mips remote
5287 target, remote targets using the gdb-specific protocol, UDI (AMD's
5288 debug protocol for the 29k) and the 88k bug monitor. It is now an
5289 integer specifying a debug level (normally 0 or 1, but 2 means more
5290 debugging info for the mips target).
5292 * DEC Alpha native support
5294 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5295 debug info, but GDB works fairly well with the DEC compiler and should
5296 work with a future GCC release. See the README file for a few
5297 Alpha-specific notes.
5299 * Preliminary thread implementation
5301 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5303 * LynxOS native and target support for 386
5305 This release has been hosted on LynxOS 2.2, and also can be configured
5306 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5309 * Improvements in C++ mangling/demangling.
5311 This release has much better g++ debugging, specifically in name
5312 mangling/demangling, virtual function calls, print virtual table,
5313 call methods, ...etc.
5315 *** Changes in GDB-4.10:
5317 * User visible changes:
5319 Remote debugging using the GDB-specific (`target remote') protocol now
5320 supports the `load' command. This is only useful if you have some
5321 other way of getting the stub to the target system, and you can put it
5322 somewhere in memory where it won't get clobbered by the download.
5324 Filename completion now works.
5326 When run under emacs mode, the "info line" command now causes the
5327 arrow to point to the line specified. Also, "info line" prints
5328 addresses in symbolic form (as well as hex).
5330 All vxworks based targets now support a user settable option, called
5331 vxworks-timeout. This option represents the number of seconds gdb
5332 should wait for responses to rpc's. You might want to use this if
5333 your vxworks target is, perhaps, a slow software simulator or happens
5334 to be on the far side of a thin network line.
5338 This release contains support for using a DEC alpha as a GDB host for
5339 cross debugging. Native alpha debugging is not supported yet.
5342 *** Changes in GDB-4.9:
5346 This is the first GDB release which is accompanied by a matching testsuite.
5347 The testsuite requires installation of dejagnu, which should be available
5348 via ftp from most sites that carry GNU software.
5352 'Cfront' style demangling has had its name changed to 'ARM' style, to
5353 emphasize that it was written from the specifications in the C++ Annotated
5354 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5355 disclaimers, it still generated too much confusion with users attempting to
5356 use gdb with AT&T cfront.
5360 GDB now uses a standard remote interface to a simulator library.
5361 So far, the library contains simulators for the Zilog Z8001/2, the
5362 Hitachi H8/300, H8/500 and Super-H.
5364 * New targets supported
5366 H8/300 simulator h8300-hitachi-hms or h8300hms
5367 H8/500 simulator h8500-hitachi-hms or h8500hms
5368 SH simulator sh-hitachi-hms or sh
5369 Z8000 simulator z8k-zilog-none or z8ksim
5370 IDT MIPS board over serial line mips-idt-ecoff
5372 Cross-debugging to GO32 targets is supported. It requires a custom
5373 version of the i386-stub.c module which is integrated with the
5374 GO32 memory extender.
5376 * New remote protocols
5378 MIPS remote debugging protocol.
5380 * New source languages supported
5382 This version includes preliminary support for Chill, a Pascal like language
5383 used by telecommunications companies. Chill support is also being integrated
5384 into the GNU compiler, but we don't know when it will be publically available.
5387 *** Changes in GDB-4.8:
5389 * HP Precision Architecture supported
5391 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5392 version of this support was available as a set of patches from the
5393 University of Utah. GDB does not support debugging of programs
5394 compiled with the HP compiler, because HP will not document their file
5395 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5396 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5398 Many problems in the preliminary version have been fixed.
5400 * Faster and better demangling
5402 We have improved template demangling and fixed numerous bugs in the GNU style
5403 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5404 character types (wchar_t) are now supported. Demangling of each symbol is now
5405 only done once, and is cached when the symbol table for a file is read in.
5406 This results in a small increase in memory usage for C programs, a moderate
5407 increase in memory usage for C++ programs, and a fantastic speedup in
5410 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5411 from the specifications in the Annotated Reference Manual, which AT&T's
5412 compiler does not actually implement.
5414 * G++ multiple inheritance compiler problem
5416 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5417 inheritance lattices was reworked to properly discover ambiguities. We
5418 recently found an example which causes this new algorithm to fail in a
5419 very subtle way, producing bad debug information for those classes.
5420 The file 'gcc.patch' (in this directory) can be applied to gcc to
5421 circumvent the problem. A future GCC release will contain a complete
5424 The previous G++ debug info problem (mentioned below for the gdb-4.7
5425 release) is fixed in gcc version 2.3.2.
5427 * Improved configure script
5429 The `configure' script will now attempt to guess your system type if
5430 you don't supply a host system type. The old scheme of supplying a
5431 host system triplet is preferable over using this. All the magic is
5432 done in the new `config.guess' script. Examine it for details.
5434 We have also brought our configure script much more in line with the FSF's
5435 version. It now supports the --with-xxx options. In particular,
5436 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5437 The resulting GDB will not be able to read arbitrary object file formats --
5438 only the format ``expected'' to be used on the configured target system.
5439 We hope to make this the default in a future release.
5441 * Documentation improvements
5443 There's new internal documentation on how to modify GDB, and how to
5444 produce clean changes to the code. We implore people to read it
5445 before submitting changes.
5447 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5448 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5449 `info' files are also provided. To build `info' files from scratch,
5450 you will need the latest `makeinfo' release, which will be available in
5451 a future texinfo-X.Y release.
5453 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5454 We're not sure exactly which versions have this problem, but it has
5455 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5456 or better. If that isn't possible, there is a patch in
5457 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5458 around this problem.
5462 GDB now supports array constants that can be used in expressions typed in by
5463 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5464 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5467 The new directory `gdb/sparclite' contains a program that demonstrates
5468 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5470 * New native hosts supported
5472 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5473 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5475 * New targets supported
5477 AMD 29k family via UDI a29k-amd-udi or udi29k
5479 * New file formats supported
5481 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5482 HPUX core files, and SCO 3.2v2 core files.
5486 Attaching to processes now works again; thanks for the many bug reports.
5488 We have also stomped on a bunch of core dumps caused by
5489 printf_filtered("%s") problems.
5491 We eliminated a copyright problem on the rpc and ptrace header files
5492 for VxWorks, which was discovered at the last minute during the 4.7
5493 release. You should now be able to build a VxWorks GDB.
5495 You can now interrupt gdb while an attached process is running. This
5496 will cause the attached process to stop, and give control back to GDB.
5498 We fixed problems caused by using too many file descriptors
5499 for reading symbols from object files and libraries. This was
5500 especially a problem for programs that used many (~100) shared
5503 The `step' command now only enters a subroutine if there is line number
5504 information for the subroutine. Otherwise it acts like the `next'
5505 command. Previously, `step' would enter subroutines if there was
5506 any debugging information about the routine. This avoids problems
5507 when using `cc -g1' on MIPS machines.
5509 * Internal improvements
5511 GDB's internal interfaces have been improved to make it easier to support
5512 debugging of multiple languages in the future.
5514 GDB now uses a common structure for symbol information internally.
5515 Minimal symbols (derived from linkage symbols in object files), partial
5516 symbols (from a quick scan of debug information), and full symbols
5517 contain a common subset of information, making it easier to write
5518 shared code that handles any of them.
5520 * New command line options
5522 We now accept --silent as an alias for --quiet.
5526 The memory-mapped-malloc library is now licensed under the GNU Library
5527 General Public License.
5529 *** Changes in GDB-4.7:
5531 * Host/native/target split
5533 GDB has had some major internal surgery to untangle the support for
5534 hosts and remote targets. Now, when you configure GDB for a remote
5535 target, it will no longer load in all of the support for debugging
5536 local programs on the host. When fully completed and tested, this will
5537 ensure that arbitrary host/target combinations are possible.
5539 The primary conceptual shift is to separate the non-portable code in
5540 GDB into three categories. Host specific code is required any time GDB
5541 is compiled on that host, regardless of the target. Target specific
5542 code relates to the peculiarities of the target, but can be compiled on
5543 any host. Native specific code is everything else: it can only be
5544 built when the host and target are the same system. Child process
5545 handling and core file support are two common `native' examples.
5547 GDB's use of /proc for controlling Unix child processes is now cleaner.
5548 It has been split out into a single module under the `target_ops' vector,
5549 plus two native-dependent functions for each system that uses /proc.
5551 * New hosts supported
5553 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5554 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5555 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5557 * New targets supported
5559 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5560 68030 and CPU32 m68030-*-*, m68332-*-*
5562 * New native hosts supported
5564 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5565 (386bsd is not well tested yet)
5566 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5568 * New file formats supported
5570 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5571 supports reading of `a.out.adobe' object files, which are an a.out
5572 format extended with minimal information about multiple sections.
5576 `show copying' is the same as the old `info copying'.
5577 `show warranty' is the same as `info warrantee'.
5578 These were renamed for consistency. The old commands continue to work.
5580 `info handle' is a new alias for `info signals'.
5582 You can now define pre-command hooks, which attach arbitrary command
5583 scripts to any command. The commands in the hook will be executed
5584 prior to the user's command. You can also create a hook which will be
5585 executed whenever the program stops. See gdb.texinfo.
5589 We now deal with Cfront style name mangling, and can even extract type
5590 info from mangled symbols. GDB can automatically figure out which
5591 symbol mangling style your C++ compiler uses.
5593 Calling of methods and virtual functions has been improved as well.
5597 The crash that occured when debugging Sun Ansi-C compiled binaries is
5598 fixed. This was due to mishandling of the extra N_SO stabs output
5601 We also finally got Ultrix 4.2 running in house, and fixed core file
5602 support, with help from a dozen people on the net.
5604 John M. Farrell discovered that the reason that single-stepping was so
5605 slow on all of the Mips based platforms (primarily SGI and DEC) was
5606 that we were trying to demangle and lookup a symbol used for internal
5607 purposes on every instruction that was being stepped through. Changing
5608 the name of that symbol so that it couldn't be mistaken for a C++
5609 mangled symbol sped things up a great deal.
5611 Rich Pixley sped up symbol lookups in general by getting much smarter
5612 about when C++ symbol mangling is necessary. This should make symbol
5613 completion (TAB on the command line) much faster. It's not as fast as
5614 we'd like, but it's significantly faster than gdb-4.6.
5618 A new user controllable variable 'call_scratch_address' can
5619 specify the location of a scratch area to be used when GDB
5620 calls a function in the target. This is necessary because the
5621 usual method of putting the scratch area on the stack does not work
5622 in systems that have separate instruction and data spaces.
5624 We integrated changes to support the 29k UDI (Universal Debugger
5625 Interface), but discovered at the last minute that we didn't have all
5626 of the appropriate copyright paperwork. We are working with AMD to
5627 resolve this, and hope to have it available soon.
5631 We have sped up the remote serial line protocol, especially for targets
5632 with lots of registers. It now supports a new `expedited status' ('T')
5633 message which can be used in place of the existing 'S' status message.
5634 This allows the remote stub to send only the registers that GDB
5635 needs to make a quick decision about single-stepping or conditional
5636 breakpoints, eliminating the need to fetch the entire register set for
5637 each instruction being stepped through.
5639 The GDB remote serial protocol now implements a write-through cache for
5640 registers, only re-reading the registers if the target has run.
5642 There is also a new remote serial stub for SPARC processors. You can
5643 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5644 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5645 processor with a serial port.
5649 Configure.in files have become much easier to read and modify. A new
5650 `table driven' format makes it more obvious what configurations are
5651 supported, and what files each one uses.
5655 There is a new opcodes library which will eventually contain all of the
5656 disassembly routines and opcode tables. At present, it only contains
5657 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5658 disassembler (binutils/objdump) to share these routines.
5660 The libiberty library is now copylefted under the GNU Library General
5661 Public License. This allows more liberal use, and was done so libg++
5662 can use it. This makes no difference to GDB, since the Library License
5663 grants all the rights from the General Public License.
5667 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5668 reference to the stabs symbol info used by the debugger. It is (as far
5669 as we know) the only published document on this fascinating topic. We
5670 encourage you to read it, compare it to the stabs information on your
5671 system, and send improvements on the document in general (to
5672 bug-gdb@prep.ai.mit.edu).
5674 And, of course, many bugs have been fixed.
5677 *** Changes in GDB-4.6:
5679 * Better support for C++ function names
5681 GDB now accepts as input the "demangled form" of C++ overloaded function
5682 names and member function names, and can do command completion on such names
5683 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5684 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5685 Make use of command completion, it is your friend.
5687 GDB also now accepts a variety of C++ mangled symbol formats. They are
5688 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5689 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5690 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5691 for the list of formats.
5693 * G++ symbol mangling problem
5695 Recent versions of gcc have a bug in how they emit debugging information for
5696 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5697 directory) can be applied to gcc to fix the problem. Alternatively, if you
5698 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5699 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5700 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5703 * New 'maintenance' command
5705 All of the commands related to hacking GDB internals have been moved out of
5706 the main command set, and now live behind the 'maintenance' command. This
5707 can also be abbreviated as 'mt'. The following changes were made:
5709 dump-me -> maintenance dump-me
5710 info all-breakpoints -> maintenance info breakpoints
5711 printmsyms -> maintenance print msyms
5712 printobjfiles -> maintenance print objfiles
5713 printpsyms -> maintenance print psymbols
5714 printsyms -> maintenance print symbols
5716 The following commands are new:
5718 maintenance demangle Call internal GDB demangler routine to
5719 demangle a C++ link name and prints the result.
5720 maintenance print type Print a type chain for a given symbol
5722 * Change to .gdbinit file processing
5724 We now read the $HOME/.gdbinit file before processing the argv arguments
5725 (e.g. reading symbol files or core files). This allows global parameters to
5726 be set, which will apply during the symbol reading. The ./.gdbinit is still
5727 read after argv processing.
5729 * New hosts supported
5731 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5733 GNU/Linux support i386-unknown-linux or linux
5735 We are also including code to support the HP/PA running BSD and HPUX. This
5736 is almost guaranteed not to work, as we didn't have time to test or build it
5737 for this release. We are including it so that the more adventurous (or
5738 masochistic) of you can play with it. We also had major problems with the
5739 fact that the compiler that we got from HP doesn't support the -g option.
5742 * New targets supported
5744 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5746 * More smarts about finding #include files
5748 GDB now remembers the compilation directory for all include files, and for
5749 all files from which C is generated (like yacc and lex sources). This
5750 greatly improves GDB's ability to find yacc/lex sources, and include files,
5751 especially if you are debugging your program from a directory different from
5752 the one that contains your sources.
5754 We also fixed a bug which caused difficulty with listing and setting
5755 breakpoints in include files which contain C code. (In the past, you had to
5756 try twice in order to list an include file that you hadn't looked at before.)
5758 * Interesting infernals change
5760 GDB now deals with arbitrary numbers of sections, where the symbols for each
5761 section must be relocated relative to that section's landing place in the
5762 target's address space. This work was needed to support ELF with embedded
5763 stabs used by Solaris-2.0.
5765 * Bug fixes (of course!)
5767 There have been loads of fixes for the following things:
5768 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5769 i960, stabs, DOS(GO32), procfs, etc...
5771 See the ChangeLog for details.
5773 *** Changes in GDB-4.5:
5775 * New machines supported (host and target)
5777 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5779 SGI Irix-4.x mips-sgi-irix4 or iris4
5781 * New malloc package
5783 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5784 Mmalloc is capable of handling mutiple heaps of memory. It is also
5785 capable of saving a heap to a file, and then mapping it back in later.
5786 This can be used to greatly speedup the startup of GDB by using a
5787 pre-parsed symbol table which lives in a mmalloc managed heap. For
5788 more details, please read mmalloc/mmalloc.texi.
5792 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5793 'help info proc' for details.
5795 * MIPS ecoff symbol table format
5797 The code that reads MIPS symbol table format is now supported on all hosts.
5798 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5801 * File name changes for MS-DOS
5803 Many files in the config directories have been renamed to make it easier to
5804 support GDB on MS-DOSe systems (which have very restrictive file name
5805 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5806 environment) is close to working but has some remaining problems. Note
5807 that debugging of DOS programs is not supported, due to limitations
5808 in the ``operating system'', but it can be used to host cross-debugging.
5810 * Cross byte order fixes
5812 Many fixes have been made to support cross debugging of Sparc and MIPS
5813 targets from hosts whose byte order differs.
5815 * New -mapped and -readnow options
5817 If memory-mapped files are available on your system through the 'mmap'
5818 system call, you can use the -mapped option on the `file' or
5819 `symbol-file' commands to cause GDB to write the symbols from your
5820 program into a reusable file. If the program you are debugging is
5821 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5822 Future GDB debugging sessions will notice the presence of this file,
5823 and will quickly map in symbol information from it, rather than reading
5824 the symbol table from the executable program. Using the '-mapped'
5825 option in a GDB `file' or `symbol-file' command has the same effect as
5826 starting GDB with the '-mapped' command-line option.
5828 You can cause GDB to read the entire symbol table immediately by using
5829 the '-readnow' option with any of the commands that load symbol table
5830 information (or on the GDB command line). This makes the command
5831 slower, but makes future operations faster.
5833 The -mapped and -readnow options are typically combined in order to
5834 build a `fred.syms' file that contains complete symbol information.
5835 A simple GDB invocation to do nothing but build a `.syms' file for future
5838 gdb -batch -nx -mapped -readnow programname
5840 The `.syms' file is specific to the host machine on which GDB is run.
5841 It holds an exact image of GDB's internal symbol table. It cannot be
5842 shared across multiple host platforms.
5844 * longjmp() handling
5846 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5847 siglongjmp() without losing control. This feature has not yet been ported to
5848 all systems. It currently works on many 386 platforms, all MIPS-based
5849 platforms (SGI, DECstation, etc), and Sun3/4.
5853 Preliminary work has been put in to support the new Solaris OS from Sun. At
5854 this time, it can control and debug processes, but it is not capable of
5859 As always, many many bug fixes. The major areas were with g++, and mipsread.
5860 People using the MIPS-based platforms should experience fewer mysterious
5861 crashes and trashed symbol tables.
5863 *** Changes in GDB-4.4:
5865 * New machines supported (host and target)
5867 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5869 BSD Reno on Vax vax-dec-bsd
5870 Ultrix on Vax vax-dec-ultrix
5872 * New machines supported (target)
5874 AMD 29000 embedded, using EBMON a29k-none-none
5878 GDB continues to improve its handling of C++. `References' work better.
5879 The demangler has also been improved, and now deals with symbols mangled as
5880 per the Annotated C++ Reference Guide.
5882 GDB also now handles `stabs' symbol information embedded in MIPS
5883 `ecoff' symbol tables. Since the ecoff format was not easily
5884 extensible to handle new languages such as C++, this appeared to be a
5885 good way to put C++ debugging info into MIPS binaries. This option
5886 will be supported in the GNU C compiler, version 2, when it is
5889 * New features for SVR4
5891 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5892 shared libraries. Debugging dynamically linked programs should present
5893 only minor differences from debugging statically linked programs.
5895 The `info proc' command will print out information about any process
5896 on an SVR4 system (including the one you are debugging). At the moment,
5897 it prints the address mappings of the process.
5899 If you bring up GDB on another SVR4 system, please send mail to
5900 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5902 * Better dynamic linking support in SunOS
5904 Reading symbols from shared libraries which contain debugging symbols
5905 now works properly. However, there remain issues such as automatic
5906 skipping of `transfer vector' code during function calls, which
5907 make it harder to debug code in a shared library, than to debug the
5908 same code linked statically.
5912 GDB is now using the latest `getopt' routines from the FSF. This
5913 version accepts the -- prefix for options with long names. GDB will
5914 continue to accept the old forms (-option and +option) as well.
5915 Various single letter abbreviations for options have been explicity
5916 added to the option table so that they won't get overshadowed in the
5917 future by other options that begin with the same letter.
5921 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5922 Many assorted bugs have been handled. Many more remain to be handled.
5923 See the various ChangeLog files (primarily in gdb and bfd) for details.
5926 *** Changes in GDB-4.3:
5928 * New machines supported (host and target)
5930 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5931 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5932 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5934 * Almost SCO Unix support
5936 We had hoped to support:
5937 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5938 (except for core file support), but we discovered very late in the release
5939 that it has problems with process groups that render gdb unusable. Sorry
5940 about that. I encourage people to fix it and post the fixes.
5942 * Preliminary ELF and DWARF support
5944 GDB can read ELF object files on System V Release 4, and can handle
5945 debugging records for C, in DWARF format, in ELF files. This support
5946 is preliminary. If you bring up GDB on another SVR4 system, please
5947 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5952 GDB now uses the latest `readline' library. One user-visible change
5953 is that two tabs will list possible command completions, which previously
5954 required typing M-? (meta-question mark, or ESC ?).
5958 The `stepi' bug that many of you noticed has been squashed.
5959 Many bugs in C++ have been handled. Many more remain to be handled.
5960 See the various ChangeLog files (primarily in gdb and bfd) for details.
5962 * State of the MIPS world (in case you wondered):
5964 GDB can understand the symbol tables emitted by the compilers
5965 supplied by most vendors of MIPS-based machines, including DEC. These
5966 symbol tables are in a format that essentially nobody else uses.
5968 Some versions of gcc come with an assembler post-processor called
5969 mips-tfile. This program is required if you want to do source-level
5970 debugging of gcc-compiled programs. I believe FSF does not ship
5971 mips-tfile with gcc version 1, but it will eventually come with gcc
5974 Debugging of g++ output remains a problem. g++ version 1.xx does not
5975 really support it at all. (If you're lucky, you should be able to get
5976 line numbers and stack traces to work, but no parameters or local
5977 variables.) With some work it should be possible to improve the
5980 When gcc version 2 is released, you will have somewhat better luck.
5981 However, even then you will get confusing results for inheritance and
5984 We will eventually provide full debugging of g++ output on
5985 DECstations. This will probably involve some kind of stabs-in-ecoff
5986 encapulation, but the details have not been worked out yet.
5989 *** Changes in GDB-4.2:
5991 * Improved configuration
5993 Only one copy of `configure' exists now, and it is not self-modifying.
5994 Porting BFD is simpler.
5998 The `step' and `next' commands now only stop at the first instruction
5999 of a source line. This prevents the multiple stops that used to occur
6000 in switch statements, for-loops, etc. `Step' continues to stop if a
6001 function that has debugging information is called within the line.
6005 Lots of small bugs fixed. More remain.
6007 * New host supported (not target)
6009 Intel 386 PC clone running Mach i386-none-mach
6012 *** Changes in GDB-4.1:
6014 * Multiple source language support
6016 GDB now has internal scaffolding to handle several source languages.
6017 It determines the type of each source file from its filename extension,
6018 and will switch expression parsing and number formatting to match the
6019 language of the function in the currently selected stack frame.
6020 You can also specifically set the language to be used, with
6021 `set language c' or `set language modula-2'.
6025 GDB now has preliminary support for the GNU Modula-2 compiler,
6026 currently under development at the State University of New York at
6027 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6028 continue through the fall of 1991 and into 1992.
6030 Other Modula-2 compilers are currently not supported, and attempting to
6031 debug programs compiled with them will likely result in an error as the
6032 symbol table is read. Feel free to work on it, though!
6034 There are hooks in GDB for strict type checking and range checking,
6035 in the `Modula-2 philosophy', but they do not currently work.
6039 GDB can now write to executable and core files (e.g. patch
6040 a variable's value). You must turn this switch on, specify
6041 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6042 by assigning a new value to a variable. Modifications take
6045 * Automatic SunOS shared library reading
6047 When you run your program, GDB automatically determines where its
6048 shared libraries (if any) have been loaded, and reads their symbols.
6049 The `share' command is no longer needed. This also works when
6050 examining core files.
6054 You can specify the number of lines that the `list' command shows.
6057 * New machines supported (host and target)
6059 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6060 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6061 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6063 * New hosts supported (not targets)
6065 IBM RT/PC: romp-ibm-aix or rtpc
6067 * New targets supported (not hosts)
6069 AMD 29000 embedded with COFF a29k-none-coff
6070 AMD 29000 embedded with a.out a29k-none-aout
6071 Ultracomputer remote kernel debug a29k-nyu-kern
6073 * New remote interfaces
6079 *** Changes in GDB-4.0:
6083 Wide output is wrapped at good places to make the output more readable.
6085 Gdb now supports cross-debugging from a host machine of one type to a
6086 target machine of another type. Communication with the target system
6087 is over serial lines. The ``target'' command handles connecting to the
6088 remote system; the ``load'' command will download a program into the
6089 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6090 also supports debugging of realtime processes running under VxWorks,
6091 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6092 stub on the target system.
6094 New CPUs supported include the AMD 29000 and Intel 960.
6096 GDB now reads object files and symbol tables via a ``binary file''
6097 library, which allows a single copy of GDB to debug programs of multiple
6098 object file types such as a.out and coff.
6100 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6101 refcard.dvi and refcard.ps are available to format it).
6104 * Control-Variable user interface simplified
6106 All variables that control the operation of the debugger can be set
6107 by the ``set'' command, and displayed by the ``show'' command.
6109 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6110 ``Show prompt'' produces the response:
6111 Gdb's prompt is new-gdb=>.
6113 What follows are the NEW set commands. The command ``help set'' will
6114 print a complete list of old and new set commands. ``help set FOO''
6115 will give a longer description of the variable FOO. ``show'' will show
6116 all of the variable descriptions and their current settings.
6118 confirm on/off: Enables warning questions for operations that are
6119 hard to recover from, e.g. rerunning the program while
6120 it is already running. Default is ON.
6122 editing on/off: Enables EMACS style command line editing
6123 of input. Previous lines can be recalled with
6124 control-P, the current line can be edited with control-B,
6125 you can search for commands with control-R, etc.
6128 history filename NAME: NAME is where the gdb command history
6129 will be stored. The default is .gdb_history,
6130 or the value of the environment variable
6133 history size N: The size, in commands, of the command history. The
6134 default is 256, or the value of the environment variable
6137 history save on/off: If this value is set to ON, the history file will
6138 be saved after exiting gdb. If set to OFF, the
6139 file will not be saved. The default is OFF.
6141 history expansion on/off: If this value is set to ON, then csh-like
6142 history expansion will be performed on
6143 command line input. The default is OFF.
6145 radix N: Sets the default radix for input and output. It can be set
6146 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6147 in the current radix, so "set radix 10" is always a no-op.
6149 height N: This integer value is the number of lines on a page. Default
6150 is 24, the current `stty rows'' setting, or the ``li#''
6151 setting from the termcap entry matching the environment
6154 width N: This integer value is the number of characters on a line.
6155 Default is 80, the current `stty cols'' setting, or the ``co#''
6156 setting from the termcap entry matching the environment
6159 Note: ``set screensize'' is obsolete. Use ``set height'' and
6160 ``set width'' instead.
6162 print address on/off: Print memory addresses in various command displays,
6163 such as stack traces and structure values. Gdb looks
6164 more ``symbolic'' if you turn this off; it looks more
6165 ``machine level'' with it on. Default is ON.
6167 print array on/off: Prettyprint arrays. New convenient format! Default
6170 print demangle on/off: Print C++ symbols in "source" form if on,
6173 print asm-demangle on/off: Same, for assembler level printouts
6176 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6179 * Support for Epoch Environment.
6181 The epoch environment is a version of Emacs v18 with windowing. One
6182 new command, ``inspect'', is identical to ``print'', except that if you
6183 are running in the epoch environment, the value is printed in its own
6187 * Support for Shared Libraries
6189 GDB can now debug programs and core files that use SunOS shared libraries.
6190 Symbols from a shared library cannot be referenced
6191 before the shared library has been linked with the program (this
6192 happens after you type ``run'' and before the function main() is entered).
6193 At any time after this linking (including when examining core files
6194 from dynamically linked programs), gdb reads the symbols from each
6195 shared library when you type the ``sharedlibrary'' command.
6196 It can be abbreviated ``share''.
6198 sharedlibrary REGEXP: Load shared object library symbols for files
6199 matching a unix regular expression. No argument
6200 indicates to load symbols for all shared libraries.
6202 info sharedlibrary: Status of loaded shared libraries.
6207 A watchpoint stops execution of a program whenever the value of an
6208 expression changes. Checking for this slows down execution
6209 tremendously whenever you are in the scope of the expression, but is
6210 quite useful for catching tough ``bit-spreader'' or pointer misuse
6211 problems. Some machines such as the 386 have hardware for doing this
6212 more quickly, and future versions of gdb will use this hardware.
6214 watch EXP: Set a watchpoint (breakpoint) for an expression.
6216 info watchpoints: Information about your watchpoints.
6218 delete N: Deletes watchpoint number N (same as breakpoints).
6219 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6220 enable N: Re-enables watchpoint number N (same as breakpoints).
6223 * C++ multiple inheritance
6225 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6228 * C++ exception handling
6230 Gdb now supports limited C++ exception handling. Besides the existing
6231 ability to breakpoint on an exception handler, gdb can breakpoint on
6232 the raising of an exception (before the stack is peeled back to the
6235 catch FOO: If there is a FOO exception handler in the dynamic scope,
6236 set a breakpoint to catch exceptions which may be raised there.
6237 Multiple exceptions (``catch foo bar baz'') may be caught.
6239 info catch: Lists all exceptions which may be caught in the
6240 current stack frame.
6243 * Minor command changes
6245 The command ``call func (arg, arg, ...)'' now acts like the print
6246 command, except it does not print or save a value if the function's result
6247 is void. This is similar to dbx usage.
6249 The ``up'' and ``down'' commands now always print the frame they end up
6250 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6251 frames without printing.
6253 * New directory command
6255 'dir' now adds directories to the FRONT of the source search path.
6256 The path starts off empty. Source files that contain debug information
6257 about the directory in which they were compiled can be found even
6258 with an empty path; Sun CC and GCC include this information. If GDB can't
6259 find your source file in the current directory, type "dir .".
6261 * Configuring GDB for compilation
6263 For normal use, type ``./configure host''. See README or gdb.texinfo
6266 GDB now handles cross debugging. If you are remotely debugging between
6267 two different machines, type ``./configure host -target=targ''.
6268 Host is the machine where GDB will run; targ is the machine
6269 where the program that you are debugging will run.
projects / external / binutils.git / blob