1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.9
6 * Support for process record-replay and reverse debugging on aarch64*-linux*
7 targets has been added. GDB now supports recording of A64 instruction set
8 including advance SIMD instructions.
10 * Support for Sun's version of the "stabs" debug file format has been removed.
12 * GDB now honors the content of the file /proc/PID/coredump_filter
13 (PID is the process ID) on GNU/Linux systems. This file can be used
14 to specify the types of memory mappings that will be included in a
15 corefile. For more information, please refer to the manual page of
16 "core(5)". GDB also has a new command: "set use-coredump-filter
17 on|off". It allows to set whether GDB will read the content of the
18 /proc/PID/coredump_filter file when generating a corefile.
20 * The "info os" command on GNU/Linux can now display information on
22 "info os cpus" Listing of all cpus/cores on the system
24 * GDB has two new commands: "set serial parity odd|even|none" and
25 "show serial parity". These allows to set or show parity for the
28 * The "info source" command now displays the producer string if it was
29 present in the debug info. This typically includes the compiler version
30 and may include things like its command line arguments.
32 * The "info dll", an alias of the "info sharedlibrary" command,
33 is now available on all platforms.
35 * Directory names supplied to the "set sysroot" commands may be
36 prefixed with "target:" to tell GDB to access shared libraries from
37 the target system, be it local or remote. This replaces the prefix
38 "remote:". The default sysroot has been changed from "" to
39 "target:". "remote:" is automatically converted to "target:" for
40 backward compatibility.
42 * The system root specified by "set sysroot" will be prepended to the
43 filename of the main executable (if reported to GDB as absolute by
44 the operating system) when starting processes remotely, and when
45 attaching to already-running local or remote processes.
47 * GDB now supports automatic location and retrieval of executable
48 files from remote targets. Remote debugging can now be initiated
49 using only a "target remote" or "target extended-remote" command
50 (no "set sysroot" or "file" commands are required). See "New remote
53 * The "dump" command now supports verilog hex format.
55 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
57 * On GNU/Linux, GDB and gdbserver are now able to access executable
58 and shared library files without a "set sysroot" command when
59 attaching to processes running in different mount namespaces from
60 the debugger. This makes it possible to attach to processes in
61 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
62 See "New remote packets" below.
64 * The "tui reg" command now provides completion for all of the
65 available register groups, including target specific groups.
67 * The HISTSIZE environment variable is no longer read when determining
68 the size of GDB's command history. GDB now instead reads the dedicated
69 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
70 disables truncation of command history. Non-numeric values of GDBHISTSIZE
75 ** Memory ports can now be unbuffered.
79 ** gdb.Objfile objects have a new attribute "username",
80 which is the name of the objfile as specified by the user,
81 without, for example, resolving symlinks.
82 ** You can now write frame unwinders in Python.
83 ** gdb.Type objects have a new method "optimized_out",
84 returning optimized out gdb.Value instance of this type.
85 ** gdb.Value objects have new methods "reference_value" and
86 "const_value" which return a reference to the value and a
87 "const" version of the value respectively.
91 maint print symbol-cache
92 Print the contents of the symbol cache.
94 maint print symbol-cache-statistics
95 Print statistics of symbol cache usage.
97 maint flush-symbol-cache
98 Flush the contents of the symbol cache.
102 Start branch trace recording using Branch Trace Store (BTS) format.
105 Evaluate expression by using the compiler and print result.
109 Explicit commands for enabling and disabling tui mode.
112 set mpx bound on i386 and amd64
113 Support for bound table investigation on Intel(R) MPX enabled applications.
117 Start branch trace recording using Intel(R) Processor Trace format.
120 Print information about branch tracing internals.
122 maint btrace packet-history
123 Print the raw branch tracing data.
125 maint btrace clear-packet-history
126 Discard the stored raw branch tracing data.
129 Discard all branch tracing data. It will be fetched and processed
130 anew by the next "record" command.
135 Renamed from "set debug dwarf2-die".
137 Renamed from "show debug dwarf2-die".
140 Renamed from "set debug dwarf2-read".
141 show debug dwarf-read
142 Renamed from "show debug dwarf2-read".
144 maint set dwarf always-disassemble
145 Renamed from "maint set dwarf2 always-disassemble".
146 maint show dwarf always-disassemble
147 Renamed from "maint show dwarf2 always-disassemble".
149 maint set dwarf max-cache-age
150 Renamed from "maint set dwarf2 max-cache-age".
151 maint show dwarf max-cache-age
152 Renamed from "maint show dwarf2 max-cache-age".
155 show debug dwarf-line
156 Control display of debugging info regarding DWARF line processing.
160 Set the maximum number of candidates to be considered during
161 completion. The default value is 200. This limit allows GDB
162 to avoid generating large completion lists, the computation of
163 which can cause the debugger to become temporarily unresponsive.
165 set history remove-duplicates
166 show history remove-duplicates
167 Control the removal of duplicate history entries.
169 maint set symbol-cache-size
170 maint show symbol-cache-size
171 Control the size of the symbol cache.
173 set|show record btrace bts buffer-size
174 Set and show the size of the ring buffer used for branch tracing in
176 The obtained size may differ from the requested size. Use "info
177 record" to see the obtained buffer size.
179 set debug linux-namespaces
180 show debug linux-namespaces
181 Control display of debugging info regarding Linux namespaces.
183 set|show record btrace pt buffer-size
184 Set and show the size of the ring buffer used for branch tracing in
185 Intel(R) Processor Trace format.
186 The obtained size may differ from the requested size. Use "info
187 record" to see the obtained buffer size.
189 maint set|show btrace pt skip-pad
190 Set and show whether PAD packets are skipped when computing the
193 * The command 'thread apply all' can now support new option '-ascending'
194 to call its specified command for all threads in ascending order.
196 * Python/Guile scripting
198 ** GDB now supports auto-loading of Python/Guile scripts contained in the
199 special section named `.debug_gdb_scripts'.
203 qXfer:btrace-conf:read
204 Return the branch trace configuration for the current thread.
206 Qbtrace-conf:bts:size
207 Set the requested ring buffer size for branch tracing in BTS format.
210 Enable Intel(R) Procesor Trace-based branch tracing for the current
211 process. The remote stub reports support for this packet to GDB's
215 Set the requested ring buffer size for branch tracing in Intel(R) Processor
219 Indicates a memory breakpoint instruction was executed, irrespective
220 of whether it was GDB that planted the breakpoint or the breakpoint
221 is hardcoded in the program. This is required for correct non-stop
225 Indicates the target stopped for a hardware breakpoint. This is
226 required for correct non-stop mode operation.
229 Return information about files on the remote system.
232 Return the full absolute name of the file that was executed to
233 create a process running on the remote system.
236 Select the filesystem on which vFile: operations with filename
237 arguments will operate. This is required for GDB to be able to
238 access files on remote targets where the remote stub does not
239 share a common filesystem with the inferior(s).
242 Indicates that a fork system call was executed.
245 Indicates that a vfork system call was executed.
247 vforkdone stop reason
248 Indicates that a vfork child of the specified process has executed
249 an exec or exit, allowing the vfork parent to resume execution.
251 fork-events and vfork-events features in qSupported
252 The qSupported packet allows GDB to request support for fork and
253 vfork events using new 'gdbfeatures' fork-events and vfork-events,
254 and the qSupported response can contain the corresponding
255 'stubfeatures'. Set and show commands can be used to display
256 whether these features are enabled.
258 * Extended-remote fork events
260 ** GDB now has support for fork events on extended-remote Linux
261 targets. For targets with Linux kernels 2.5.60 and later, this
262 enables follow-fork-mode and detach-on-fork for both fork and
263 vfork, as well as fork and vfork catchpoints.
265 * The info record command now shows the recording format and the
266 branch tracing configuration for the current thread when using
267 the btrace record target.
268 For the BTS format, it shows the ring buffer size.
270 * GDB now has support for DTrace USDT (Userland Static Defined
271 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
273 * GDB now supports access to vector registers on S/390 GNU/Linux
276 * Removed command line options
278 -xdb HP-UX XDB compatibility mode.
280 * Removed targets and native configurations
282 HP/PA running HP-UX hppa*-*-hpux*
283 Itanium running HP-UX ia64-*-hpux*
285 * New configure options
288 This configure option allows the user to build GDB with support for
289 Intel(R) Processor Trace (default: auto). This requires libipt.
291 --with-libipt-prefix=PATH
292 Specify the path to the version of libipt that GDB should use.
293 $PATH/include should contain the intel-pt.h header and
294 $PATH/lib should contain the libipt.so library.
296 *** Changes in GDB 7.9.1
300 ** Xmethods can now specify a result type.
302 *** Changes in GDB 7.9
304 * GDB now supports hardware watchpoints on x86 GNU Hurd.
308 ** You can now access frame registers from Python scripts.
309 ** New attribute 'producer' for gdb.Symtab objects.
310 ** gdb.Objfile objects have a new attribute "progspace",
311 which is the gdb.Progspace object of the containing program space.
312 ** gdb.Objfile objects have a new attribute "owner".
313 ** gdb.Objfile objects have a new attribute "build_id",
314 which is the build ID generated when the file was built.
315 ** gdb.Objfile objects have a new method "add_separate_debug_file".
316 ** A new event "gdb.clear_objfiles" has been added, triggered when
317 selecting a new file to debug.
318 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
319 ** New function gdb.lookup_objfile.
321 New events which are triggered when GDB modifies the state of the
324 ** gdb.events.inferior_call_pre: Function call is about to be made.
325 ** gdb.events.inferior_call_post: Function call has just been made.
326 ** gdb.events.memory_changed: A memory location has been altered.
327 ** gdb.events.register_changed: A register has been altered.
329 * New Python-based convenience functions:
331 ** $_caller_is(name [, number_of_frames])
332 ** $_caller_matches(regexp [, number_of_frames])
333 ** $_any_caller_is(name [, number_of_frames])
334 ** $_any_caller_matches(regexp [, number_of_frames])
336 * GDB now supports the compilation and injection of source code into
337 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
338 to compile the source code to object code, and if successful, inject
339 and execute that code within the current context of the inferior.
340 Currently the C language is supported. The commands used to
341 interface with this new feature are:
343 compile code [-raw|-r] [--] [source code]
344 compile file [-raw|-r] filename
348 demangle [-l language] [--] name
349 Demangle "name" in the specified language, or the current language
350 if elided. This command is renamed from the "maint demangle" command.
351 The latter is kept as a no-op to avoid "maint demangle" being interpreted
352 as "maint demangler-warning".
354 queue-signal signal-name-or-number
355 Queue a signal to be delivered to the thread when it is resumed.
357 add-auto-load-scripts-directory directory
358 Add entries to the list of directories from which to load auto-loaded
361 maint print user-registers
362 List all currently available "user" registers.
364 compile code [-r|-raw] [--] [source code]
365 Compile, inject, and execute in the inferior the executable object
366 code produced by compiling the provided source code.
368 compile file [-r|-raw] filename
369 Compile and inject into the inferior the executable object code
370 produced by compiling the source code stored in the filename
373 * On resume, GDB now always passes the signal the program had stopped
374 for to the thread the signal was sent to, even if the user changed
375 threads before resuming. Previously GDB would often (but not
376 always) deliver the signal to the thread that happens to be current
379 * Conversely, the "signal" command now consistently delivers the
380 requested signal to the current thread. GDB now asks for
381 confirmation if the program had stopped for a signal and the user
382 switched threads meanwhile.
384 * "breakpoint always-inserted" modes "off" and "auto" merged.
386 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
387 won't remove breakpoints from the target until all threads stop,
388 even in non-stop mode. The "auto" mode has been removed, and "off"
389 is now the default mode.
393 set debug symbol-lookup
394 show debug symbol-lookup
395 Control display of debugging info regarding symbol lookup.
399 ** The -list-thread-groups command outputs an exit-code field for
400 inferiors that have exited.
404 MIPS SDE mips*-sde*-elf*
408 Support for these obsolete configurations has been removed.
410 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
411 SGI Irix-5.x mips-*-irix5*
412 SGI Irix-6.x mips-*-irix6*
413 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
414 VAX running Ultrix vax-*-ultrix*
416 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
417 and "assf"), have been removed. Use the "sharedlibrary" command, or
418 its alias "share", instead.
420 *** Changes in GDB 7.8
422 * New command line options
425 This is an alias for the --data-directory option.
427 * GDB supports printing and modifying of variable length automatic arrays
428 as specified in ISO C99.
430 * The ARM simulator now supports instruction level tracing
431 with or without disassembly.
435 GDB now has support for scripting using Guile. Whether this is
436 available is determined at configure time.
437 Guile version 2.0 or greater is required.
438 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
440 * New commands (for set/show, see "New options" below)
444 Invoke CODE by passing it to the Guile interpreter.
448 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
450 info auto-load guile-scripts [regexp]
451 Print the list of automatically loaded Guile scripts.
453 * The source command is now capable of sourcing Guile scripts.
454 This feature is dependent on the debugger being built with Guile support.
458 set print symbol-loading (off|brief|full)
459 show print symbol-loading
460 Control whether to print informational messages when loading symbol
461 information for a file. The default is "full", but when debugging
462 programs with large numbers of shared libraries the amount of output
465 set guile print-stack (none|message|full)
466 show guile print-stack
467 Show a stack trace when an error is encountered in a Guile script.
469 set auto-load guile-scripts (on|off)
470 show auto-load guile-scripts
471 Control auto-loading of Guile script files.
473 maint ada set ignore-descriptive-types (on|off)
474 maint ada show ignore-descriptive-types
475 Control whether the debugger should ignore descriptive types in Ada
476 programs. The default is not to ignore the descriptive types. See
477 the user manual for more details on descriptive types and the intended
478 usage of this option.
480 set auto-connect-native-target
482 Control whether GDB is allowed to automatically connect to the
483 native target for the run, attach, etc. commands when not connected
484 to any target yet. See also "target native" below.
486 set record btrace replay-memory-access (read-only|read-write)
487 show record btrace replay-memory-access
488 Control what memory accesses are allowed during replay.
490 maint set target-async (on|off)
491 maint show target-async
492 This controls whether GDB targets operate in synchronous or
493 asynchronous mode. Normally the default is asynchronous, if it is
494 available; but this can be changed to more easily debug problems
495 occurring only in synchronous mode.
497 set mi-async (on|off)
499 Control whether MI asynchronous mode is preferred. This supersedes
500 "set target-async" of previous GDB versions.
502 * "set target-async" is deprecated as a CLI option and is now an alias
503 for "set mi-async" (only puts MI into async mode).
505 * Background execution commands (e.g., "c&", "s&", etc.) are now
506 possible ``out of the box'' if the target supports them. Previously
507 the user would need to explicitly enable the possibility with the
508 "set target-async on" command.
510 * New features in the GDB remote stub, GDBserver
512 ** New option --debug-format=option1[,option2,...] allows one to add
513 additional text to each output. At present only timestamps
514 are supported: --debug-format=timestamps.
515 Timestamps can also be turned on with the
516 "monitor set debug-format timestamps" command from GDB.
518 * The 'record instruction-history' command now starts counting instructions
519 at one. This also affects the instruction ranges reported by the
520 'record function-call-history' command when given the /i modifier.
522 * The command 'record function-call-history' supports a new modifier '/c' to
523 indent the function names based on their call stack depth.
524 The fields for the '/i' and '/l' modifier have been reordered.
525 The source line range is now prefixed with 'at'.
526 The instruction range is now prefixed with 'inst'.
527 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
528 "record instruction-history" and "list" commands.
530 * The ranges given as arguments to the 'record function-call-history' and
531 'record instruction-history' commands are now inclusive.
533 * The btrace record target now supports the 'record goto' command.
534 For locations inside the execution trace, the back trace is computed
535 based on the information stored in the execution trace.
537 * The btrace record target supports limited reverse execution and replay.
538 The target does not record data and therefore does not allow reading
541 * The "catch syscall" command now works on s390*-linux* targets.
543 * The "compare-sections" command is no longer specific to target
544 remote. It now works with all targets.
546 * All native targets are now consistently called "native".
547 Consequently, the "target child", "target GNU", "target djgpp",
548 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
549 commands have been replaced with "target native". The QNX/NTO port
550 leaves the "procfs" target in place and adds a "native" target for
551 consistency with other ports. The impact on users should be minimal
552 as these commands previously either throwed an error, or were
553 no-ops. The target's name is visible in the output of the following
554 commands: "help target", "info target", "info files", "maint print
557 * The "target native" command now connects to the native target. This
558 can be used to launch native programs even when "set
559 auto-connect-native-target" is set to off.
561 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
563 * Support for Intel(R) AVX-512 registers on GNU/Linux.
564 Support displaying and modifying Intel(R) AVX-512 registers
565 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
569 qXfer:btrace:read's annex
570 The qXfer:btrace:read packet supports a new annex 'delta' to read
571 branch trace incrementally.
575 ** Valid Python operations on gdb.Value objects representing
576 structs/classes invoke the corresponding overloaded operators if
578 ** New `Xmethods' feature in the Python API. Xmethods are
579 additional methods or replacements for existing methods of a C++
580 class. This feature is useful for those cases where a method
581 defined in C++ source code could be inlined or optimized out by
582 the compiler, making it unavailable to GDB.
585 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
587 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
588 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
589 its alias "share", instead.
591 * The commands "set remotebaud" and "show remotebaud" are no longer
592 supported. Use "set serial baud" and "show serial baud" (respectively)
597 ** A new option "-gdb-set mi-async" replaces "-gdb-set
598 target-async". The latter is left as a deprecated alias of the
599 former for backward compatibility. If the target supports it,
600 CLI background execution commands are now always possible by
601 default, independently of whether the frontend stated a
602 preference for asynchronous execution with "-gdb-set mi-async".
603 Previously "-gdb-set target-async off" affected both MI execution
604 commands and CLI execution commands.
606 *** Changes in GDB 7.7
608 * Improved support for process record-replay and reverse debugging on
609 arm*-linux* targets. Support for thumb32 and syscall instruction
610 recording has been added.
612 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
614 * GDB now supports Fission DWP file format version 2.
615 http://gcc.gnu.org/wiki/DebugFission
617 * New convenience function "$_isvoid", to check whether an expression
618 is void. A void expression is an expression where the type of the
619 result is "void". For example, some convenience variables may be
620 "void" when evaluated (e.g., "$_exitcode" before the execution of
621 the program being debugged; or an undefined convenience variable).
622 Another example, when calling a function whose return type is
625 * The "maintenance print objfiles" command now takes an optional regexp.
627 * The "catch syscall" command now works on arm*-linux* targets.
629 * GDB now consistently shows "<not saved>" when printing values of
630 registers the debug info indicates have not been saved in the frame
631 and there's nowhere to retrieve them from
632 (callee-saved/call-clobbered registers):
637 (gdb) info registers rax
640 Before, the former would print "<optimized out>", and the latter
641 "*value not available*".
643 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
648 ** Frame filters and frame decorators have been added.
649 ** Temporary breakpoints are now supported.
650 ** Line tables representation has been added.
651 ** New attribute 'parent_type' for gdb.Field objects.
652 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
653 ** New attribute 'name' for gdb.Type objects.
657 Nios II ELF nios2*-*-elf
658 Nios II GNU/Linux nios2*-*-linux
659 Texas Instruments MSP430 msp430*-*-elf
661 * Removed native configurations
663 Support for these a.out NetBSD and OpenBSD obsolete configurations has
664 been removed. ELF variants of these configurations are kept supported.
666 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
667 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
668 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
669 i[34567]86-*-openbsd3.[0-3]
670 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
671 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
672 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
676 Like "catch throw", but catches a re-thrown exception.
678 Renamed from old "maint check-symtabs".
680 Perform consistency checks on symtabs.
682 Expand symtabs matching an optional regexp.
685 Display the details of GDB configure-time options.
687 maint set|show per-command
688 maint set|show per-command space
689 maint set|show per-command time
690 maint set|show per-command symtab
691 Enable display of per-command gdb resource usage.
693 remove-symbol-file FILENAME
694 remove-symbol-file -a ADDRESS
695 Remove a symbol file added via add-symbol-file. The file to remove
696 can be identified by its filename or by an address that lies within
697 the boundaries of this symbol file in memory.
700 info exceptions REGEXP
701 Display the list of Ada exceptions defined in the program being
702 debugged. If provided, only the exceptions whose names match REGEXP
707 set debug symfile off|on
709 Control display of debugging info regarding reading symbol files and
710 symbol tables within those files
712 set print raw frame-arguments
713 show print raw frame-arguments
714 Set/show whether to print frame arguments in raw mode,
715 disregarding any defined pretty-printers.
717 set remote trace-status-packet
718 show remote trace-status-packet
719 Set/show the use of remote protocol qTStatus packet.
723 Control display of debugging messages related to Nios II targets.
727 Control whether target-assisted range stepping is enabled.
729 set startup-with-shell
730 show startup-with-shell
731 Specifies whether Unix child processes are started via a shell or
736 Use the target memory cache for accesses to the code segment. This
737 improves performance of remote debugging (particularly disassembly).
739 * You can now use a literal value 'unlimited' for options that
740 interpret 0 or -1 as meaning "unlimited". E.g., "set
741 trace-buffer-size unlimited" is now an alias for "set
742 trace-buffer-size -1" and "set height unlimited" is now an alias for
745 * The "set debug symtab-create" debugging option of GDB has been changed to
746 accept a verbosity level. 0 means "off", 1 provides basic debugging
747 output, and values of 2 or greater provides more verbose output.
749 * New command-line options
751 Display the details of GDB configure-time options.
753 * The command 'tsave' can now support new option '-ctf' to save trace
754 buffer in Common Trace Format.
756 * Newly installed $prefix/bin/gcore acts as a shell interface for the
759 * GDB now implements the the C++ 'typeid' operator.
761 * The new convenience variable $_exception holds the exception being
762 thrown or caught at an exception-related catchpoint.
764 * The exception-related catchpoints, like "catch throw", now accept a
765 regular expression which can be used to filter exceptions by type.
767 * The new convenience variable $_exitsignal is automatically set to
768 the terminating signal number when the program being debugged dies
769 due to an uncaught signal.
773 ** All MI commands now accept an optional "--language" option.
774 Support for this feature can be verified by using the "-list-features"
775 command, which should contain "language-option".
777 ** The new command -info-gdb-mi-command allows the user to determine
778 whether a GDB/MI command is supported or not.
780 ** The "^error" result record returned when trying to execute an undefined
781 GDB/MI command now provides a variable named "code" whose content is the
782 "undefined-command" error code. Support for this feature can be verified
783 by using the "-list-features" command, which should contain
784 "undefined-command-error-code".
786 ** The -trace-save MI command can optionally save trace buffer in Common
789 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
791 ** The command -data-list-register-values now accepts an optional
792 "--skip-unavailable" option. When used, only the available registers
795 ** The new command -trace-frame-collected dumps collected variables,
796 computed expressions, tvars, memory and registers in a traceframe.
798 ** The commands -stack-list-locals, -stack-list-arguments and
799 -stack-list-variables now accept an option "--skip-unavailable".
800 When used, only the available locals or arguments are displayed.
802 ** The -exec-run command now accepts an optional "--start" option.
803 When used, the command follows the same semantics as the "start"
804 command, stopping the program's execution at the start of its
805 main subprogram. Support for this feature can be verified using
806 the "-list-features" command, which should contain
807 "exec-run-start-option".
809 ** The new commands -catch-assert and -catch-exceptions insert
810 catchpoints stopping the program when Ada exceptions are raised.
812 ** The new command -info-ada-exceptions provides the equivalent of
813 the new "info exceptions" command.
815 * New system-wide configuration scripts
816 A GDB installation now provides scripts suitable for use as system-wide
817 configuration scripts for the following systems:
821 * GDB now supports target-assigned range stepping with remote targets.
822 This improves the performance of stepping source lines by reducing
823 the number of control packets from/to GDB. See "New remote packets"
826 * GDB now understands the element 'tvar' in the XML traceframe info.
827 It has the id of the collected trace state variables.
829 * On S/390 targets that provide the transactional-execution feature,
830 the program interruption transaction diagnostic block (TDB) is now
831 represented as a number of additional "registers" in GDB.
837 The vCont packet supports a new 'r' action, that tells the remote
838 stub to step through an address range itself, without GDB
839 involvemement at each single-step.
841 qXfer:libraries-svr4:read's annex
842 The previously unused annex of the qXfer:libraries-svr4:read packet
843 is now used to support passing an argument list. The remote stub
844 reports support for this argument list to GDB's qSupported query.
845 The defined arguments are "start" and "prev", used to reduce work
846 necessary for library list updating, resulting in significant
849 * New features in the GDB remote stub, GDBserver
851 ** GDBserver now supports target-assisted range stepping. Currently
852 enabled on x86/x86_64 GNU/Linux targets.
854 ** GDBserver now adds element 'tvar' in the XML in the reply to
855 'qXfer:traceframe-info:read'. It has the id of the collected
856 trace state variables.
858 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
861 * New 'z' formatter for printing and examining memory, this displays the
862 value as hexadecimal zero padded on the left to the size of the type.
864 * GDB can now use Windows x64 unwinding data.
866 * The "set remotebaud" command has been replaced by "set serial baud".
867 Similarly, "show remotebaud" has been replaced by "show serial baud".
868 The "set remotebaud" and "show remotebaud" commands are still available
869 to provide backward compatibility with older versions of GDB.
871 *** Changes in GDB 7.6
873 * Target record has been renamed to record-full.
874 Record/replay is now enabled with the "record full" command.
875 This also affects settings that are associated with full record/replay
876 that have been moved from "set/show record" to "set/show record full":
878 set|show record full insn-number-max
879 set|show record full stop-at-limit
880 set|show record full memory-query
882 * A new record target "record-btrace" has been added. The new target
883 uses hardware support to record the control-flow of a process. It
884 does not support replaying the execution, but it implements the
885 below new commands for investigating the recorded execution log.
886 This new recording method can be enabled using:
890 The "record-btrace" target is only available on Intel Atom processors
891 and requires a Linux kernel 2.6.32 or later.
893 * Two new commands have been added for record/replay to give information
894 about the recorded execution without having to replay the execution.
895 The commands are only supported by "record btrace".
897 record instruction-history prints the execution history at
898 instruction granularity
900 record function-call-history prints the execution history at
903 * New native configurations
905 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
906 FreeBSD/powerpc powerpc*-*-freebsd
907 x86_64/Cygwin x86_64-*-cygwin*
908 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
912 ARM AArch64 aarch64*-*-elf
913 ARM AArch64 GNU/Linux aarch64*-*-linux
914 Lynx 178 PowerPC powerpc-*-lynx*178
915 x86_64/Cygwin x86_64-*-cygwin*
916 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
918 * If the configured location of system.gdbinit file (as given by the
919 --with-system-gdbinit option at configure time) is in the
920 data-directory (as specified by --with-gdb-datadir at configure
921 time) or in one of its subdirectories, then GDB will look for the
922 system-wide init file in the directory specified by the
923 --data-directory command-line option.
925 * New command line options:
927 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
928 other initialization files, unlike -nx which disables all of them.
930 * Removed command line options
932 -epoch This was used by the gdb mode in Epoch, an ancient fork of
935 * The 'ptype' and 'whatis' commands now accept an argument to control
938 * 'info proc' now works on some core files.
942 ** Vectors can be created with gdb.Type.vector.
944 ** Python's atexit.register now works in GDB.
946 ** Types can be pretty-printed via a Python API.
948 ** Python 3 is now supported (in addition to Python 2.4 or later)
950 ** New class gdb.Architecture exposes GDB's internal representation
951 of architecture in the Python API.
953 ** New method Frame.architecture returns the gdb.Architecture object
954 corresponding to the frame's architecture.
956 * New Python-based convenience functions:
958 ** $_memeq(buf1, buf2, length)
959 ** $_streq(str1, str2)
961 ** $_regex(str, regex)
963 * The 'cd' command now defaults to using '~' (the home directory) if not
966 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
967 default for GCC since November 2000.
969 * The command 'forward-search' can now be abbreviated as 'fo'.
971 * The command 'info tracepoints' can now display 'installed on target'
972 or 'not installed on target' for each non-pending location of tracepoint.
974 * New configure options
976 --enable-libmcheck/--disable-libmcheck
977 By default, development versions are built with -lmcheck on hosts
978 that support it, in order to help track memory corruption issues.
979 Release versions, on the other hand, are built without -lmcheck
980 by default. The --enable-libmcheck/--disable-libmcheck configure
981 options allow the user to override that default.
982 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
983 This configure option allows the user to build GDB with
984 libbabeltrace using which GDB can read Common Trace Format data.
986 * New commands (for set/show, see "New options" below)
989 Catch signals. This is similar to "handle", but allows commands and
990 conditions to be attached.
993 List the BFDs known to GDB.
995 python-interactive [command]
997 Start a Python interactive prompt, or evaluate the optional command
998 and print the result of expressions.
1001 "py" is a new alias for "python".
1003 enable type-printer [name]...
1004 disable type-printer [name]...
1005 Enable or disable type printers.
1009 ** For the Renesas Super-H architecture, the "regs" command has been removed
1010 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1015 set print type methods (on|off)
1016 show print type methods
1017 Control whether method declarations are displayed by "ptype".
1018 The default is to show them.
1020 set print type typedefs (on|off)
1021 show print type typedefs
1022 Control whether typedef definitions are displayed by "ptype".
1023 The default is to show them.
1025 set filename-display basename|relative|absolute
1026 show filename-display
1027 Control the way in which filenames is displayed.
1028 The default is "relative", which preserves previous behavior.
1030 set trace-buffer-size
1031 show trace-buffer-size
1032 Request target to change the size of trace buffer.
1034 set remote trace-buffer-size-packet auto|on|off
1035 show remote trace-buffer-size-packet
1036 Control the use of the remote protocol `QTBuffer:size' packet.
1040 Control display of debugging messages related to ARM AArch64.
1043 set debug coff-pe-read
1044 show debug coff-pe-read
1045 Control display of debugging messages related to reading of COFF/PE
1050 Control display of debugging messages related to Mach-O symbols
1053 set debug notification
1054 show debug notification
1055 Control display of debugging info for async remote notification.
1059 ** Command parameter changes are now notified using new async record
1060 "=cmd-param-changed".
1061 ** Trace frame changes caused by command "tfind" are now notified using
1062 new async record "=traceframe-changed".
1063 ** The creation, deletion and modification of trace state variables
1064 are now notified using new async records "=tsv-created",
1065 "=tsv-deleted" and "=tsv-modified".
1066 ** The start and stop of process record are now notified using new
1067 async record "=record-started" and "=record-stopped".
1068 ** Memory changes are now notified using new async record
1070 ** The data-disassemble command response will include a "fullname" field
1071 containing the absolute file name when source has been requested.
1072 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1073 command, to allow pattern filling of memory areas.
1074 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1075 library load/unload events.
1076 ** The response to breakpoint commands and breakpoint async records
1077 includes an "installed" field containing a boolean state about each
1078 non-pending tracepoint location is whether installed on target or not.
1079 ** Output of the "-trace-status" command includes a "trace-file" field
1080 containing the name of the trace file being examined. This field is
1081 optional, and only present when examining a trace file.
1082 ** The "fullname" field is now always present along with the "file" field,
1083 even if the file cannot be found by GDB.
1085 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1086 You must have the LZMA library available when configuring GDB for this
1087 feature to be enabled. For more information, see:
1088 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1090 * New remote packets
1093 Set the size of trace buffer. The remote stub reports support for this
1094 packet to gdb's qSupported query.
1097 Enable Branch Trace Store (BTS)-based branch tracing for the current
1098 thread. The remote stub reports support for this packet to gdb's
1102 Disable branch tracing for the current thread. The remote stub reports
1103 support for this packet to gdb's qSupported query.
1106 Read the traced branches for the current thread. The remote stub
1107 reports support for this packet to gdb's qSupported query.
1109 *** Changes in GDB 7.5
1111 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1112 for more x32 ABI info.
1114 * GDB now supports access to MIPS DSP registers on Linux targets.
1116 * GDB now supports debugging microMIPS binaries.
1118 * The "info os" command on GNU/Linux can now display information on
1119 several new classes of objects managed by the operating system:
1120 "info os procgroups" lists process groups
1121 "info os files" lists file descriptors
1122 "info os sockets" lists internet-domain sockets
1123 "info os shm" lists shared-memory regions
1124 "info os semaphores" lists semaphores
1125 "info os msg" lists message queues
1126 "info os modules" lists loaded kernel modules
1128 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1129 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1130 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1131 options and inspect the probe arguments using the new $_probe_arg family
1132 of convenience variables. You can obtain more information about SystemTap
1133 in <http://sourceware.org/systemtap/>.
1135 * GDB now supports reversible debugging on ARM, it allows you to
1136 debug basic ARM and THUMB instructions, and provides
1137 record/replay support.
1139 * The option "symbol-reloading" has been deleted as it is no longer used.
1143 ** GDB commands implemented in Python can now be put in command class
1146 ** The "maint set python print-stack on|off" is now deleted.
1148 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1149 apply "flag enum"-style pretty-printing to any enum.
1151 ** gdb.lookup_symbol can now work when there is no current frame.
1153 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1154 the source at which the symbol was defined.
1156 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1157 method 'value'. The former indicates whether the symbol needs a
1158 frame in order to compute its value, and the latter computes the
1161 ** A new method 'referenced_value' on gdb.Value objects which can
1162 dereference pointer as well as C++ reference values.
1164 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1165 which return the global and static blocks (as gdb.Block objects),
1166 of the underlying symbol table, respectively.
1168 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1169 object associated with a PC value.
1171 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1172 of the address range occupied by code for the current source line.
1174 * Go language support.
1175 GDB now supports debugging programs written in the Go programming
1178 * GDBserver now supports stdio connections.
1179 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1181 * The binary "gdbtui" can no longer be built or installed.
1182 Use "gdb -tui" instead.
1184 * GDB will now print "flag" enums specially. A flag enum is one where
1185 all the enumerator values have no bits in common when pairwise
1186 "and"ed. When printing a value whose type is a flag enum, GDB will
1187 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1188 (gdb) print (enum E) 3
1191 * The filename part of a linespec will now match trailing components
1192 of a source file name. For example, "break gcc/expr.c:1000" will
1193 now set a breakpoint in build/gcc/expr.c, but not
1194 build/libcpp/expr.c.
1196 * The "info proc" and "generate-core-file" commands will now also
1197 work on remote targets connected to GDBserver on Linux.
1199 * The command "info catch" has been removed. It has been disabled
1200 since December 2007.
1202 * The "catch exception" and "catch assert" commands now accept
1203 a condition at the end of the command, much like the "break"
1204 command does. For instance:
1206 (gdb) catch exception Constraint_Error if Barrier = True
1208 Previously, it was possible to add a condition to such catchpoints,
1209 but it had to be done as a second step, after the catchpoint had been
1210 created, using the "condition" command.
1212 * The "info static-tracepoint-marker" command will now also work on
1213 native Linux targets with in-process agent.
1215 * GDB can now set breakpoints on inlined functions.
1217 * The .gdb_index section has been updated to include symbols for
1218 inlined functions. GDB will ignore older .gdb_index sections by
1219 default, which could cause symbol files to be loaded more slowly
1220 until their .gdb_index sections can be recreated. The new command
1221 "set use-deprecated-index-sections on" will cause GDB to use any older
1222 .gdb_index sections it finds. This will restore performance, but the
1223 ability to set breakpoints on inlined functions will be lost in symbol
1224 files with older .gdb_index sections.
1226 The .gdb_index section has also been updated to record more information
1227 about each symbol. This speeds up the "info variables", "info functions"
1228 and "info types" commands when used with programs having the .gdb_index
1229 section, as well as speeding up debugging with shared libraries using
1230 the .gdb_index section.
1232 * Ada support for GDB/MI Variable Objects has been added.
1234 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1239 ** New command -info-os is the MI equivalent of "info os".
1241 ** Output logs ("set logging" and related) now include MI output.
1245 ** "set use-deprecated-index-sections on|off"
1246 "show use-deprecated-index-sections on|off"
1247 Controls the use of deprecated .gdb_index sections.
1249 ** "catch load" and "catch unload" can be used to stop when a shared
1250 library is loaded or unloaded, respectively.
1252 ** "enable count" can be used to auto-disable a breakpoint after
1255 ** "info vtbl" can be used to show the virtual method tables for
1256 C++ and Java objects.
1258 ** "explore" and its sub commands "explore value" and "explore type"
1259 can be used to recursively explore values and types of
1260 expressions. These commands are available only if GDB is
1261 configured with '--with-python'.
1263 ** "info auto-load" shows status of all kinds of auto-loaded files,
1264 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1265 sequences of commands files, "info auto-load python-scripts"
1266 shows status of auto-loading Python script files,
1267 "info auto-load local-gdbinit" shows status of loading init file
1268 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1269 status of inferior specific thread debugging shared library loading.
1271 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1272 and "show auto-load-scripts" commands have been deprecated, use their
1273 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1274 and "show auto-load python-scripts" counterparts instead.
1276 ** "dprintf location,format,args..." creates a dynamic printf, which
1277 is basically a breakpoint that does a printf and immediately
1278 resumes your program's execution, so it is like a printf that you
1279 can insert dynamically at runtime instead of at compiletime.
1281 ** "set print symbol"
1283 Controls whether GDB attempts to display the symbol, if any,
1284 corresponding to addresses it prints. This defaults to "on", but
1285 you can set it to "off" to restore GDB's previous behavior.
1287 * Deprecated commands
1289 ** For the Renesas Super-H architecture, the "regs" command has been
1290 deprecated, and "info all-registers" should be used instead.
1294 Renesas RL78 rl78-*-elf
1295 HP OpenVMS ia64 ia64-hp-openvms*
1297 * GDBserver supports evaluation of breakpoint conditions. When
1298 support is advertised by GDBserver, GDB may be told to send the
1299 breakpoint conditions in bytecode form to GDBserver. GDBserver
1300 will only report the breakpoint trigger to GDB when its condition
1305 set mips compression
1306 show mips compression
1307 Select the compressed ISA encoding used in functions that have no symbol
1308 information available. The encoding can be set to either of:
1311 and is updated automatically from ELF file flags if available.
1313 set breakpoint condition-evaluation
1314 show breakpoint condition-evaluation
1315 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1316 GDBserver ("target"). Default option "auto" chooses the most efficient
1318 This option can improve debugger efficiency depending on the speed of the
1322 Disable auto-loading globally.
1325 Show auto-loading setting of all kinds of auto-loaded files.
1327 set auto-load gdb-scripts on|off
1328 show auto-load gdb-scripts
1329 Control auto-loading of GDB canned sequences of commands files.
1331 set auto-load python-scripts on|off
1332 show auto-load python-scripts
1333 Control auto-loading of Python script files.
1335 set auto-load local-gdbinit on|off
1336 show auto-load local-gdbinit
1337 Control loading of init file (.gdbinit) from current directory.
1339 set auto-load libthread-db on|off
1340 show auto-load libthread-db
1341 Control auto-loading of inferior specific thread debugging shared library.
1343 set auto-load scripts-directory <dir1>[:<dir2>...]
1344 show auto-load scripts-directory
1345 Set a list of directories from which to load auto-loaded scripts.
1346 Automatically loaded Python scripts and GDB scripts are located in one
1347 of the directories listed by this option.
1348 The delimiter (':' above) may differ according to the host platform.
1350 set auto-load safe-path <dir1>[:<dir2>...]
1351 show auto-load safe-path
1352 Set a list of directories from which it is safe to auto-load files.
1353 The delimiter (':' above) may differ according to the host platform.
1355 set debug auto-load on|off
1356 show debug auto-load
1357 Control display of debugging info for auto-loading the files above.
1359 set dprintf-style gdb|call|agent
1361 Control the way in which a dynamic printf is performed; "gdb"
1362 requests a GDB printf command, while "call" causes dprintf to call a
1363 function in the inferior. "agent" requests that the target agent
1364 (such as GDBserver) do the printing.
1366 set dprintf-function <expr>
1367 show dprintf-function
1368 set dprintf-channel <expr>
1369 show dprintf-channel
1370 Set the function and optional first argument to the call when using
1371 the "call" style of dynamic printf.
1373 set disconnected-dprintf on|off
1374 show disconnected-dprintf
1375 Control whether agent-style dynamic printfs continue to be in effect
1376 after GDB disconnects.
1378 * New configure options
1380 --with-auto-load-dir
1381 Configure default value for the 'set auto-load scripts-directory'
1382 setting above. It defaults to '$debugdir:$datadir/auto-load',
1383 $debugdir representing global debugging info directories (available
1384 via 'show debug-file-directory') and $datadir representing GDB's data
1385 directory (available via 'show data-directory').
1387 --with-auto-load-safe-path
1388 Configure default value for the 'set auto-load safe-path' setting
1389 above. It defaults to the --with-auto-load-dir setting.
1391 --without-auto-load-safe-path
1392 Set 'set auto-load safe-path' to '/', effectively disabling this
1395 * New remote packets
1397 z0/z1 conditional breakpoints extension
1399 The z0/z1 breakpoint insertion packets have been extended to carry
1400 a list of conditional expressions over to the remote stub depending on the
1401 condition evaluation mode. The use of this extension can be controlled
1402 via the "set remote conditional-breakpoints-packet" command.
1406 Specify the signals which the remote stub may pass to the debugged
1407 program without GDB involvement.
1409 * New command line options
1411 --init-command=FILE, -ix Like --command, -x but execute it
1412 before loading inferior.
1413 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1414 execute it before loading inferior.
1416 *** Changes in GDB 7.4
1418 * GDB now handles ambiguous linespecs more consistently; the existing
1419 FILE:LINE support has been expanded to other types of linespecs. A
1420 breakpoint will now be set on all matching locations in all
1421 inferiors, and locations will be added or removed according to
1424 * GDB now allows you to skip uninteresting functions and files when
1425 stepping with the "skip function" and "skip file" commands.
1427 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1428 and "show remote hardware-watchpoint-length-limit". These allows to
1429 set or show the maximum length limit (in bytes) of a remote
1430 target hardware watchpoint.
1432 This allows e.g. to use "unlimited" hardware watchpoints with the
1433 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1434 watchpoints are slower than real hardware watchpoints but are
1435 significantly faster than gdb software watchpoints.
1439 ** The register_pretty_printer function in module gdb.printing now takes
1440 an optional `replace' argument. If True, the new printer replaces any
1443 ** The "maint set python print-stack on|off" command has been
1444 deprecated and will be deleted in GDB 7.5.
1445 A new command: "set python print-stack none|full|message" has
1446 replaced it. Additionally, the default for "print-stack" is
1447 now "message", which just prints the error message without
1450 ** A prompt substitution hook (prompt_hook) is now available to the
1453 ** A new Python module, gdb.prompt has been added to the GDB Python
1454 modules library. This module provides functionality for
1455 escape sequences in prompts (used by set/show
1456 extended-prompt). These escape sequences are replaced by their
1457 corresponding value.
1459 ** Python commands and convenience-functions located in
1460 'data-directory'/python/gdb/command and
1461 'data-directory'/python/gdb/function are now automatically loaded
1464 ** Blocks now provide four new attributes. global_block and
1465 static_block will return the global and static blocks
1466 respectively. is_static and is_global are boolean attributes
1467 that indicate if the block is one of those two types.
1469 ** Symbols now provide the "type" attribute, the type of the symbol.
1471 ** The "gdb.breakpoint" function has been deprecated in favor of
1474 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1475 of a function. This class is based on the "finish" command
1476 available in the CLI.
1478 ** Type objects for struct and union types now allow access to
1479 the fields using standard Python dictionary (mapping) methods.
1480 For example, "some_type['myfield']" now works, as does
1481 "some_type.items()".
1483 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1486 ** A new function, "deep_items" has been added to the gdb.types
1487 module in the GDB Python modules library. This function returns
1488 an iterator over the fields of a struct or union type. Unlike
1489 the standard Python "iteritems" method, it will recursively traverse
1490 any anonymous fields.
1494 ** "*stopped" events can report several new "reason"s, such as
1497 ** Breakpoint changes are now notified using new async records, like
1498 "=breakpoint-modified".
1500 ** New command -ada-task-info.
1502 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1503 $sdir specifies the default system locations of shared libraries.
1504 $pdir specifies the directory where the libpthread used by the application
1507 GDB no longer looks in $sdir and $pdir after it has searched the directories
1508 mentioned in libthread-db-search-path. If you want to search those
1509 directories, they must be specified in libthread-db-search-path.
1510 The default value of libthread-db-search-path on GNU/Linux and Solaris
1511 systems is now "$sdir:$pdir".
1513 $pdir is not supported by gdbserver, it is currently ignored.
1514 $sdir is supported by gdbserver.
1516 * New configure option --with-iconv-bin.
1517 When using the internationalization support like the one in the GNU C
1518 library, GDB will invoke the "iconv" program to get a list of supported
1519 character sets. If this program lives in a non-standard location, one can
1520 use this option to specify where to find it.
1522 * When natively debugging programs on PowerPC BookE processors running
1523 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1524 watchpoints, which specify a mask in addition to an address to watch.
1525 The mask specifies that some bits of an address (the bits which are
1526 reset in the mask) should be ignored when matching the address accessed
1527 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1528 section in the user manual for more details.
1530 * The new option --once causes GDBserver to stop listening for connections once
1531 the first connection is made. The listening port used by GDBserver will
1532 become available after that.
1534 * New commands "info macros" and "alias" have been added.
1536 * New function parameters suffix @entry specifies value of function parameter
1537 at the time the function got called. Entry values are available only since
1543 "!" is now an alias of the "shell" command.
1544 Note that no space is needed between "!" and SHELL COMMAND.
1548 watch EXPRESSION mask MASK_VALUE
1549 The watch command now supports the mask argument which allows creation
1550 of masked watchpoints, if the current architecture supports this feature.
1552 info auto-load-scripts [REGEXP]
1553 This command was formerly named "maintenance print section-scripts".
1554 It is now generally useful and is no longer a maintenance-only command.
1556 info macro [-all] [--] MACRO
1557 The info macro command has new options `-all' and `--'. The first for
1558 printing all definitions of a macro. The second for explicitly specifying
1559 the end of arguments and the beginning of the macro name in case the macro
1560 name starts with a hyphen.
1562 collect[/s] EXPRESSIONS
1563 The tracepoint collect command now takes an optional modifier "/s"
1564 that directs it to dereference pointer-to-character types and
1565 collect the bytes of memory up to a zero byte. The behavior is
1566 similar to what you see when you use the regular print command on a
1567 string. An optional integer following the "/s" sets a bound on the
1568 number of bytes that will be collected.
1571 The trace start command now interprets any supplied arguments as a
1572 note to be recorded with the trace run, with an effect similar to
1573 setting the variable trace-notes.
1576 The trace stop command now interprets any arguments as a note to be
1577 mentioned along with the tstatus report that the trace was stopped
1578 with a command. The effect is similar to setting the variable
1581 * Tracepoints can now be enabled and disabled at any time after a trace
1582 experiment has been started using the standard "enable" and "disable"
1583 commands. It is now possible to start a trace experiment with no enabled
1584 tracepoints; GDB will display a warning, but will allow the experiment to
1585 begin, assuming that tracepoints will be enabled as needed while the trace
1588 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1589 locations with 4-byte instructions, when they were previously
1590 limited to locations with instructions of 5 bytes or longer.
1594 set debug dwarf2-read
1595 show debug dwarf2-read
1596 Turns on or off display of debugging messages related to reading
1597 DWARF debug info. The default is off.
1599 set debug symtab-create
1600 show debug symtab-create
1601 Turns on or off display of debugging messages related to symbol table
1602 creation. The default is off.
1605 show extended-prompt
1606 Set the GDB prompt, and allow escape sequences to be inserted to
1607 display miscellaneous information (see 'help set extended-prompt'
1608 for the list of sequences). This prompt (and any information
1609 accessed through the escape sequences) is updated every time the
1610 prompt is displayed.
1612 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1613 show print entry-values
1614 Set printing of frame argument values at function entry. In some cases
1615 GDB can determine the value of function argument which was passed by the
1616 function caller, even if the value was modified inside the called function.
1618 set debug entry-values
1619 show debug entry-values
1620 Control display of debugging info for determining frame argument values at
1621 function entry and virtual tail call frames.
1623 set basenames-may-differ
1624 show basenames-may-differ
1625 Set whether a source file may have multiple base names.
1626 (A "base name" is the name of a file with the directory part removed.
1627 Example: The base name of "/home/user/hello.c" is "hello.c".)
1628 If set, GDB will canonicalize file names (e.g., expand symlinks)
1629 before comparing them. Canonicalization is an expensive operation,
1630 but it allows the same file be known by more than one base name.
1631 If not set (the default), all source files are assumed to have just
1632 one base name, and gdb will do file name comparisons more efficiently.
1638 Set a user name and notes for the current and any future trace runs.
1639 This is useful for long-running and/or disconnected traces, to
1640 inform others (or yourself) as to who is running the trace, supply
1641 contact information, or otherwise explain what is going on.
1643 set trace-stop-notes
1644 show trace-stop-notes
1645 Set a note attached to the trace run, that is displayed when the
1646 trace has been stopped by a tstop command. This is useful for
1647 instance as an explanation, if you are stopping a trace run that was
1648 started by someone else.
1650 * New remote packets
1654 Dynamically enable a tracepoint in a started trace experiment.
1658 Dynamically disable a tracepoint in a started trace experiment.
1662 Set the user and notes of the trace run.
1666 Query the current status of a tracepoint.
1670 Query the minimum length of instruction at which a fast tracepoint may
1673 * Dcache size (number of lines) and line-size are now runtime-configurable
1674 via "set dcache line" and "set dcache line-size" commands.
1678 Texas Instruments TMS320C6x tic6x-*-*
1682 Renesas RL78 rl78-*-elf
1684 *** Changes in GDB 7.3.1
1686 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1688 *** Changes in GDB 7.3
1690 * GDB has a new command: "thread find [REGEXP]".
1691 It finds the thread id whose name, target id, or thread extra info
1692 matches the given regular expression.
1694 * The "catch syscall" command now works on mips*-linux* targets.
1696 * The -data-disassemble MI command now supports modes 2 and 3 for
1697 dumping the instruction opcodes.
1699 * New command line options
1701 -data-directory DIR Specify DIR as the "data-directory".
1702 This is mostly for testing purposes.
1704 * The "maint set python auto-load on|off" command has been renamed to
1705 "set auto-load-scripts on|off".
1707 * GDB has a new command: "set directories".
1708 It is like the "dir" command except that it replaces the
1709 source path list instead of augmenting it.
1711 * GDB now understands thread names.
1713 On GNU/Linux, "info threads" will display the thread name as set by
1714 prctl or pthread_setname_np.
1716 There is also a new command, "thread name", which can be used to
1717 assign a name internally for GDB to display.
1720 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1721 has been integrated into GDB.
1725 ** The function gdb.Write now accepts an optional keyword 'stream'.
1726 This keyword, when provided, will direct the output to either
1727 stdout, stderr, or GDB's logging output.
1729 ** Parameters can now be be sub-classed in Python, and in particular
1730 you may implement the get_set_doc and get_show_doc functions.
1731 This improves how Parameter set/show documentation is processed
1732 and allows for more dynamic content.
1734 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1735 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1736 have an is_valid method.
1738 ** Breakpoints can now be sub-classed in Python, and in particular
1739 you may implement a 'stop' function that is executed each time
1740 the inferior reaches that breakpoint.
1742 ** New function gdb.lookup_global_symbol looks up a global symbol.
1744 ** GDB values in Python are now callable if the value represents a
1745 function. For example, if 'some_value' represents a function that
1746 takes two integer parameters and returns a value, you can call
1747 that function like so:
1749 result = some_value (10,20)
1751 ** Module gdb.types has been added.
1752 It contains a collection of utilities for working with gdb.Types objects:
1753 get_basic_type, has_field, make_enum_dict.
1755 ** Module gdb.printing has been added.
1756 It contains utilities for writing and registering pretty-printers.
1757 New classes: PrettyPrinter, SubPrettyPrinter,
1758 RegexpCollectionPrettyPrinter.
1759 New function: register_pretty_printer.
1761 ** New commands "info pretty-printers", "enable pretty-printer" and
1762 "disable pretty-printer" have been added.
1764 ** gdb.parameter("directories") is now available.
1766 ** New function gdb.newest_frame returns the newest frame in the
1769 ** The gdb.InferiorThread class has a new "name" attribute. This
1770 holds the thread's name.
1772 ** Python Support for Inferior events.
1773 Python scripts can add observers to be notified of events
1774 occurring in the process being debugged.
1775 The following events are currently supported:
1776 - gdb.events.cont Continue event.
1777 - gdb.events.exited Inferior exited event.
1778 - gdb.events.stop Signal received, and Breakpoint hit events.
1782 ** GDB now puts template parameters in scope when debugging in an
1783 instantiation. For example, if you have:
1785 template<int X> int func (void) { return X; }
1787 then if you step into func<5>, "print X" will show "5". This
1788 feature requires proper debuginfo support from the compiler; it
1789 was added to GCC 4.5.
1791 ** The motion commands "next", "finish", "until", and "advance" now
1792 work better when exceptions are thrown. In particular, GDB will
1793 no longer lose control of the inferior; instead, the GDB will
1794 stop the inferior at the point at which the exception is caught.
1795 This functionality requires a change in the exception handling
1796 code that was introduced in GCC 4.5.
1798 * GDB now follows GCC's rules on accessing volatile objects when
1799 reading or writing target state during expression evaluation.
1800 One notable difference to prior behavior is that "print x = 0"
1801 no longer generates a read of x; the value of the assignment is
1802 now always taken directly from the value being assigned.
1804 * GDB now has some support for using labels in the program's source in
1805 linespecs. For instance, you can use "advance label" to continue
1806 execution to a label.
1808 * GDB now has support for reading and writing a new .gdb_index
1809 section. This section holds a fast index of DWARF debugging
1810 information and can be used to greatly speed up GDB startup and
1811 operation. See the documentation for `save gdb-index' for details.
1813 * The "watch" command now accepts an optional "-location" argument.
1814 When used, this causes GDB to watch the memory referred to by the
1815 expression. Such a watchpoint is never deleted due to it going out
1818 * GDB now supports thread debugging of core dumps on GNU/Linux.
1820 GDB now activates thread debugging using the libthread_db library
1821 when debugging GNU/Linux core dumps, similarly to when debugging
1822 live processes. As a result, when debugging a core dump file, GDB
1823 is now able to display pthread_t ids of threads. For example, "info
1824 threads" shows the same output as when debugging the process when it
1825 was live. In earlier releases, you'd see something like this:
1828 * 1 LWP 6780 main () at main.c:10
1830 While now you see this:
1833 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1835 It is also now possible to inspect TLS variables when debugging core
1838 When debugging a core dump generated on a machine other than the one
1839 used to run GDB, you may need to point GDB at the correct
1840 libthread_db library with the "set libthread-db-search-path"
1841 command. See the user manual for more details on this command.
1843 * When natively debugging programs on PowerPC BookE processors running
1844 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1845 which stop execution of the inferior whenever it executes an instruction
1846 at any address within the specified range. See the "PowerPC Embedded"
1847 section in the user manual for more details.
1849 * New features in the GDB remote stub, GDBserver
1851 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1852 and i686 LynxOS (version 5.x).
1854 ** GDBserver is now supported on Blackfin Linux.
1856 * New native configurations
1858 ia64 HP-UX ia64-*-hpux*
1862 Analog Devices, Inc. Blackfin Processor bfin-*
1864 * Ada task switching is now supported on sparc-elf targets when
1865 debugging a program using the Ravenscar Profile. For more information,
1866 see the "Tasking Support when using the Ravenscar Profile" section
1867 in the GDB user manual.
1869 * Guile support was removed.
1871 * New features in the GNU simulator
1873 ** The --map-info flag lists all known core mappings.
1875 ** CFI flashes may be simulated via the "cfi" device.
1877 *** Changes in GDB 7.2
1879 * Shared library support for remote targets by default
1881 When GDB is configured for a generic, non-OS specific target, like
1882 for example, --target=arm-eabi or one of the many *-*-elf targets,
1883 GDB now queries remote stubs for loaded shared libraries using the
1884 `qXfer:libraries:read' packet. Previously, shared library support
1885 was always disabled for such configurations.
1889 ** Argument Dependent Lookup (ADL)
1891 In C++ ADL lookup directs function search to the namespaces of its
1892 arguments even if the namespace has not been imported.
1902 Here the compiler will search for `foo' in the namespace of 'b'
1903 and find A::foo. GDB now supports this. This construct is commonly
1904 used in the Standard Template Library for operators.
1906 ** Improved User Defined Operator Support
1908 In addition to member operators, GDB now supports lookup of operators
1909 defined in a namespace and imported with a `using' directive, operators
1910 defined in the global scope, operators imported implicitly from an
1911 anonymous namespace, and the ADL operators mentioned in the previous
1913 GDB now also supports proper overload resolution for all the previously
1914 mentioned flavors of operators.
1916 ** static const class members
1918 Printing of static const class members that are initialized in the
1919 class definition has been fixed.
1921 * Windows Thread Information Block access.
1923 On Windows targets, GDB now supports displaying the Windows Thread
1924 Information Block (TIB) structure. This structure is visible either
1925 by using the new command `info w32 thread-information-block' or, by
1926 dereferencing the new convenience variable named `$_tlb', a
1927 thread-specific pointer to the TIB. This feature is also supported
1928 when remote debugging using GDBserver.
1930 * Static tracepoints
1932 Static tracepoints are calls in the user program into a tracing
1933 library. One such library is a port of the LTTng kernel tracer to
1934 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1935 When debugging with GDBserver, GDB now supports combining the GDB
1936 tracepoint machinery with such libraries. For example: the user can
1937 use GDB to probe a static tracepoint marker (a call from the user
1938 program into the tracing library) with the new "strace" command (see
1939 "New commands" below). This creates a "static tracepoint" in the
1940 breakpoint list, that can be manipulated with the same feature set
1941 as fast and regular tracepoints. E.g., collect registers, local and
1942 global variables, collect trace state variables, and define
1943 tracepoint conditions. In addition, the user can collect extra
1944 static tracepoint marker specific data, by collecting the new
1945 $_sdata internal variable. When analyzing the trace buffer, you can
1946 inspect $_sdata like any other variable available to GDB. For more
1947 information, see the "Tracepoints" chapter in GDB user manual. New
1948 remote packets have been defined to support static tracepoints, see
1949 the "New remote packets" section below.
1951 * Better reconstruction of tracepoints after disconnected tracing
1953 GDB will attempt to download the original source form of tracepoint
1954 definitions when starting a trace run, and then will upload these
1955 upon reconnection to the target, resulting in a more accurate
1956 reconstruction of the tracepoints that are in use on the target.
1960 You can now exercise direct control over the ways that GDB can
1961 affect your program. For instance, you can disallow the setting of
1962 breakpoints, so that the program can run continuously (assuming
1963 non-stop mode). In addition, the "observer" variable is available
1964 to switch all of the different controls; in observer mode, GDB
1965 cannot affect the target's behavior at all, which is useful for
1966 tasks like diagnosing live systems in the field.
1968 * The new convenience variable $_thread holds the number of the
1971 * New remote packets
1975 Return the address of the Windows Thread Information Block of a given thread.
1979 In response to several of the tracepoint packets, the target may now
1980 also respond with a number of intermediate `qRelocInsn' request
1981 packets before the final result packet, to have GDB handle
1982 relocating an instruction to execute at a different address. This
1983 is particularly useful for stubs that support fast tracepoints. GDB
1984 reports support for this feature in the qSupported packet.
1988 List static tracepoint markers in the target program.
1992 List static tracepoint markers at a given address in the target
1995 qXfer:statictrace:read
1997 Read the static trace data collected (by a `collect $_sdata'
1998 tracepoint action). The remote stub reports support for this packet
1999 to gdb's qSupported query.
2003 Send the current settings of GDB's permission flags.
2007 Send part of the source (textual) form of a tracepoint definition,
2008 which includes location, conditional, and action list.
2010 * The source command now accepts a -s option to force searching for the
2011 script in the source search path even if the script name specifies
2014 * New features in the GDB remote stub, GDBserver
2016 - GDBserver now support tracepoints (including fast tracepoints, and
2017 static tracepoints). The feature is currently supported by the
2018 i386-linux and amd64-linux builds. See the "Tracepoints support
2019 in gdbserver" section in the manual for more information.
2021 GDBserver JIT compiles the tracepoint's conditional agent
2022 expression bytecode into native code whenever possible for low
2023 overhead dynamic tracepoints conditionals. For such tracepoints,
2024 an expression that examines program state is evaluated when the
2025 tracepoint is reached, in order to determine whether to capture
2026 trace data. If the condition is simple and false, processing the
2027 tracepoint finishes very quickly and no data is gathered.
2029 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2030 for static tracepoints support.
2032 - GDBserver now supports x86_64 Windows 64-bit debugging.
2034 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2035 it understands register description.
2037 * The --batch flag now disables pagination and queries.
2039 * X86 general purpose registers
2041 GDB now supports reading/writing byte, word and double-word x86
2042 general purpose registers directly. This means you can use, say,
2043 $ah or $ax to refer, respectively, to the byte register AH and
2044 16-bit word register AX that are actually portions of the 32-bit
2045 register EAX or 64-bit register RAX.
2047 * The `commands' command now accepts a range of breakpoints to modify.
2048 A plain `commands' following a command that creates multiple
2049 breakpoints affects all the breakpoints set by that command. This
2050 applies to breakpoints set by `rbreak', and also applies when a
2051 single `break' command creates multiple breakpoints (e.g.,
2052 breakpoints on overloaded c++ functions).
2054 * The `rbreak' command now accepts a filename specification as part of
2055 its argument, limiting the functions selected by the regex to those
2056 in the specified file.
2058 * Support for remote debugging Windows and SymbianOS shared libraries
2059 from Unix hosts has been improved. Non Windows GDB builds now can
2060 understand target reported file names that follow MS-DOS based file
2061 system semantics, such as file names that include drive letters and
2062 use the backslash character as directory separator. This makes it
2063 possible to transparently use the "set sysroot" and "set
2064 solib-search-path" on Unix hosts to point as host copies of the
2065 target's shared libraries. See the new command "set
2066 target-file-system-kind" described below, and the "Commands to
2067 specify files" section in the user manual for more information.
2071 eval template, expressions...
2072 Convert the values of one or more expressions under the control
2073 of the string template to a command line, and call it.
2075 set target-file-system-kind unix|dos-based|auto
2076 show target-file-system-kind
2077 Set or show the assumed file system kind for target reported file
2080 save breakpoints <filename>
2081 Save all current breakpoint definitions to a file suitable for use
2082 in a later debugging session. To read the saved breakpoint
2083 definitions, use the `source' command.
2085 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2088 info static-tracepoint-markers
2089 Display information about static tracepoint markers in the target.
2091 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2092 Define a static tracepoint by probing a marker at the given
2093 function, line, address, or marker ID.
2097 Enable and disable observer mode.
2099 set may-write-registers on|off
2100 set may-write-memory on|off
2101 set may-insert-breakpoints on|off
2102 set may-insert-tracepoints on|off
2103 set may-insert-fast-tracepoints on|off
2104 set may-interrupt on|off
2105 Set individual permissions for GDB effects on the target. Note that
2106 some of these settings can have undesirable or surprising
2107 consequences, particularly when changed in the middle of a session.
2108 For instance, disabling the writing of memory can prevent
2109 breakpoints from being inserted, cause single-stepping to fail, or
2110 even crash your program, if you disable after breakpoints have been
2111 inserted. However, GDB should not crash.
2113 set record memory-query on|off
2114 show record memory-query
2115 Control whether to stop the inferior if memory changes caused
2116 by an instruction cannot be recorded.
2121 The disassemble command now supports "start,+length" form of two arguments.
2125 ** GDB now provides a new directory location, called the python directory,
2126 where Python scripts written for GDB can be installed. The location
2127 of that directory is <data-directory>/python, where <data-directory>
2128 is the GDB data directory. For more details, see section `Scripting
2129 GDB using Python' in the manual.
2131 ** The GDB Python API now has access to breakpoints, symbols, symbol
2132 tables, program spaces, inferiors, threads and frame's code blocks.
2133 Additionally, GDB Parameters can now be created from the API, and
2134 manipulated via set/show in the CLI.
2136 ** New functions gdb.target_charset, gdb.target_wide_charset,
2137 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2139 ** New exception gdb.GdbError.
2141 ** Pretty-printers are now also looked up in the current program space.
2143 ** Pretty-printers can now be individually enabled and disabled.
2145 ** GDB now looks for names of Python scripts to auto-load in a
2146 special section named `.debug_gdb_scripts', in addition to looking
2147 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2149 * Tracepoint actions were unified with breakpoint commands. In particular,
2150 there are no longer differences in "info break" output for breakpoints and
2151 tracepoints and the "commands" command can be used for both tracepoints and
2152 regular breakpoints.
2156 ARM Symbian arm*-*-symbianelf*
2158 * D language support.
2159 GDB now supports debugging programs written in the D programming
2162 * GDB now supports the extended ptrace interface for PowerPC which is
2163 available since Linux kernel version 2.6.34. This automatically enables
2164 any hardware breakpoints and additional hardware watchpoints available in
2165 the processor. The old ptrace interface exposes just one hardware
2166 watchpoint and no hardware breakpoints.
2168 * GDB is now able to use the Data Value Compare (DVC) register available on
2169 embedded PowerPC processors to implement in hardware simple watchpoint
2170 conditions of the form:
2172 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2174 This works in native GDB running on Linux kernels with the extended ptrace
2175 interface mentioned above.
2177 *** Changes in GDB 7.1
2181 ** Namespace Support
2183 GDB now supports importing of namespaces in C++. This enables the
2184 user to inspect variables from imported namespaces. Support for
2185 namepace aliasing has also been added. So, if a namespace is
2186 aliased in the current scope (e.g. namepace C=A; ) the user can
2187 print variables using the alias (e.g. (gdb) print C::x).
2191 All known bugs relating to the printing of virtual base class were
2192 fixed. It is now possible to call overloaded static methods using a
2197 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2198 and reinterpret_cast<> are now handled by the C++ expression parser.
2202 Xilinx MicroBlaze microblaze-*-*
2207 Xilinx MicroBlaze microblaze
2210 * Multi-program debugging.
2212 GDB now has support for multi-program (a.k.a. multi-executable or
2213 multi-exec) debugging. This allows for debugging multiple inferiors
2214 simultaneously each running a different program under the same GDB
2215 session. See "Debugging Multiple Inferiors and Programs" in the
2216 manual for more information. This implied some user visible changes
2217 in the multi-inferior support. For example, "info inferiors" now
2218 lists inferiors that are not running yet or that have exited
2219 already. See also "New commands" and "New options" below.
2221 * New tracing features
2223 GDB's tracepoint facility now includes several new features:
2225 ** Trace state variables
2227 GDB tracepoints now include support for trace state variables, which
2228 are variables managed by the target agent during a tracing
2229 experiment. They are useful for tracepoints that trigger each
2230 other, so for instance one tracepoint can count hits in a variable,
2231 and then a second tracepoint has a condition that is true when the
2232 count reaches a particular value. Trace state variables share the
2233 $-syntax of GDB convenience variables, and can appear in both
2234 tracepoint actions and condition expressions. Use the "tvariable"
2235 command to create, and "info tvariables" to view; see "Trace State
2236 Variables" in the manual for more detail.
2240 GDB now includes an option for defining fast tracepoints, which
2241 targets may implement more efficiently, such as by installing a jump
2242 into the target agent rather than a trap instruction. The resulting
2243 speedup can be by two orders of magnitude or more, although the
2244 tradeoff is that some program locations on some target architectures
2245 might not allow fast tracepoint installation, for instance if the
2246 instruction to be replaced is shorter than the jump. To request a
2247 fast tracepoint, use the "ftrace" command, with syntax identical to
2248 the regular trace command.
2250 ** Disconnected tracing
2252 It is now possible to detach GDB from the target while it is running
2253 a trace experiment, then reconnect later to see how the experiment
2254 is going. In addition, a new variable disconnected-tracing lets you
2255 tell the target agent whether to continue running a trace if the
2256 connection is lost unexpectedly.
2260 GDB now has the ability to save the trace buffer into a file, and
2261 then use that file as a target, similarly to you can do with
2262 corefiles. You can select trace frames, print data that was
2263 collected in them, and use tstatus to display the state of the
2264 tracing run at the moment that it was saved. To create a trace
2265 file, use "tsave <filename>", and to use it, do "target tfile
2268 ** Circular trace buffer
2270 You can ask the target agent to handle the trace buffer as a
2271 circular buffer, discarding the oldest trace frames to make room for
2272 newer ones, by setting circular-trace-buffer to on. This feature may
2273 not be available for all target agents.
2278 The disassemble command, when invoked with two arguments, now requires
2279 the arguments to be comma-separated.
2282 The info variables command now displays variable definitions. Files
2283 which only declare a variable are not shown.
2286 The source command is now capable of sourcing Python scripts.
2287 This feature is dependent on the debugger being build with Python
2290 Related to this enhancement is also the introduction of a new command
2291 "set script-extension" (see below).
2293 * New commands (for set/show, see "New options" below)
2295 record save [<FILENAME>]
2296 Save a file (in core file format) containing the process record
2297 execution log for replay debugging at a later time.
2299 record restore <FILENAME>
2300 Restore the process record execution log that was saved at an
2301 earlier time, for replay debugging.
2303 add-inferior [-copies <N>] [-exec <FILENAME>]
2306 clone-inferior [-copies <N>] [ID]
2307 Make a new inferior ready to execute the same program another
2308 inferior has loaded.
2313 maint info program-spaces
2314 List the program spaces loaded into GDB.
2316 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2317 show remote interrupt-sequence
2318 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2319 as the sequence to the remote target in order to interrupt the execution.
2320 Ctrl-C is a default. Some system prefers BREAK which is high level of
2321 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2322 Magic SysRq g. It is BREAK signal and character 'g'.
2324 set remote interrupt-on-connect [on | off]
2325 show remote interrupt-on-connect
2326 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2327 remote target when gdb connects to it. This is needed when you debug
2330 set remotebreak [on | off]
2332 Deprecated. Use "set/show remote interrupt-sequence" instead.
2334 tvariable $NAME [ = EXP ]
2335 Create or modify a trace state variable.
2338 List trace state variables and their values.
2340 delete tvariable $NAME ...
2341 Delete one or more trace state variables.
2344 Evaluate the given expressions without collecting anything into the
2345 trace buffer. (Valid in tracepoint actions only.)
2347 ftrace FN / FILE:LINE / *ADDR
2348 Define a fast tracepoint at the given function, line, or address.
2350 * New expression syntax
2352 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2353 GDB now parses 0b101010 identically with 42.
2357 set follow-exec-mode new|same
2358 show follow-exec-mode
2359 Control whether GDB reuses the same inferior across an exec call or
2360 creates a new one. This is useful to be able to restart the old
2361 executable after the inferior having done an exec call.
2363 set default-collect EXPR, ...
2364 show default-collect
2365 Define a list of expressions to be collected at each tracepoint.
2366 This is a useful way to ensure essential items are not overlooked,
2367 such as registers or a critical global variable.
2369 set disconnected-tracing
2370 show disconnected-tracing
2371 If set to 1, the target is instructed to continue tracing if it
2372 loses its connection to GDB. If 0, the target is to stop tracing
2375 set circular-trace-buffer
2376 show circular-trace-buffer
2377 If set to on, the target is instructed to use a circular trace buffer
2378 and discard the oldest trace frames instead of stopping the trace due
2379 to a full trace buffer. If set to off, the trace stops when the buffer
2380 fills up. Some targets may not support this.
2382 set script-extension off|soft|strict
2383 show script-extension
2384 If set to "off", the debugger does not perform any script language
2385 recognition, and all sourced files are assumed to be GDB scripts.
2386 If set to "soft" (the default), files are sourced according to
2387 filename extension, falling back to GDB scripts if the first
2389 If set to "strict", files are sourced according to filename extension.
2391 set ada trust-PAD-over-XVS on|off
2392 show ada trust-PAD-over-XVS
2393 If off, activate a workaround against a bug in the debugging information
2394 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2395 the GCC sources for more information about the GNAT encoding and
2396 PAD types in particular). It is always safe to set this option to
2397 off, but this introduces a slight performance penalty. The default
2400 * Python API Improvements
2402 ** GDB provides the new class gdb.LazyString. This is useful in
2403 some pretty-printing cases. The new method gdb.Value.lazy_string
2404 provides a simple way to create objects of this type.
2406 ** The fields returned by gdb.Type.fields now have an
2407 `is_base_class' attribute.
2409 ** The new method gdb.Type.range returns the range of an array type.
2411 ** The new method gdb.parse_and_eval can be used to parse and
2412 evaluate an expression.
2414 * New remote packets
2417 Define a trace state variable.
2420 Get the current value of a trace state variable.
2423 Set desired tracing behavior upon disconnection.
2426 Set the trace buffer to be linear or circular.
2429 Get data about the tracepoints currently in use.
2433 Process record now works correctly with hardware watchpoints.
2435 Multiple bug fixes have been made to the mips-irix port, making it
2436 much more reliable. In particular:
2437 - Debugging threaded applications is now possible again. Previously,
2438 GDB would hang while starting the program, or while waiting for
2439 the program to stop at a breakpoint.
2440 - Attaching to a running process no longer hangs.
2441 - An error occurring while loading a core file has been fixed.
2442 - Changing the value of the PC register now works again. This fixes
2443 problems observed when using the "jump" command, or when calling
2444 a function from GDB, or even when assigning a new value to $pc.
2445 - With the "finish" and "return" commands, the return value for functions
2446 returning a small array is now correctly printed.
2447 - It is now possible to break on shared library code which gets executed
2448 during a shared library init phase (code executed while executing
2449 their .init section). Previously, the breakpoint would have no effect.
2450 - GDB is now able to backtrace through the signal handler for
2451 non-threaded programs.
2453 PIE (Position Independent Executable) programs debugging is now supported.
2454 This includes debugging execution of PIC (Position Independent Code) shared
2455 libraries although for that, it should be possible to run such libraries as an
2458 *** Changes in GDB 7.0
2460 * GDB now has an interface for JIT compilation. Applications that
2461 dynamically generate code can create symbol files in memory and register
2462 them with GDB. For users, the feature should work transparently, and
2463 for JIT developers, the interface is documented in the GDB manual in the
2464 "JIT Compilation Interface" chapter.
2466 * Tracepoints may now be conditional. The syntax is as for
2467 breakpoints; either an "if" clause appended to the "trace" command,
2468 or the "condition" command is available. GDB sends the condition to
2469 the target for evaluation using the same bytecode format as is used
2470 for tracepoint actions.
2472 * The disassemble command now supports: an optional /r modifier, print the
2473 raw instructions in hex as well as in symbolic form, and an optional /m
2474 modifier to print mixed source+assembly.
2476 * Process record and replay
2478 In a architecture environment that supports ``process record and
2479 replay'', ``process record and replay'' target can record a log of
2480 the process execution, and replay it with both forward and reverse
2483 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2484 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2485 set execution-direction {forward|reverse}, for targets that support
2488 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2489 feature is available with a native GDB running on kernel version
2492 * GDB now has support for multi-byte and wide character sets on the
2493 target. Strings whose character type is wchar_t, char16_t, or
2494 char32_t are now correctly printed. GDB supports wide- and unicode-
2495 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2496 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2497 `printf'. This feature requires iconv to work properly; if your
2498 system does not have a working iconv, GDB can use GNU libiconv. See
2499 the installation instructions for more information.
2501 * GDB now supports automatic retrieval of shared library files from
2502 remote targets. To use this feature, specify a system root that begins
2503 with the `remote:' prefix, either via the `set sysroot' command or via
2504 the `--with-sysroot' configure-time option.
2506 * "info sharedlibrary" now takes an optional regex of libraries to show,
2507 and it now reports if a shared library has no debugging information.
2509 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2510 now complete on file names.
2512 * When completing in expressions, gdb will attempt to limit
2513 completions to allowable structure or union fields, where appropriate.
2514 For instance, consider:
2516 # struct example { int f1; double f2; };
2517 # struct example variable;
2520 If the user types TAB at the end of this command line, the available
2521 completions will be "f1" and "f2".
2523 * Inlined functions are now supported. They show up in backtraces, and
2524 the "step", "next", and "finish" commands handle them automatically.
2526 * GDB now supports the token-splicing (##) and stringification (#)
2527 operators when expanding macros. It also supports variable-arity
2530 * GDB now supports inspecting extra signal information, exported by
2531 the new $_siginfo convenience variable. The feature is currently
2532 implemented on linux ARM, i386 and amd64.
2534 * GDB can now display the VFP floating point registers and NEON vector
2535 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2536 can provide these registers (requires Linux 2.6.30 or later). Remote
2537 and simulator targets may also provide them.
2539 * New remote packets
2542 Search memory for a sequence of bytes.
2545 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2546 operation over reliable transport links. Use of this packet is
2547 controlled by the `set remote noack-packet' command.
2550 Kill the process with the specified process ID. Use this in preference
2551 to `k' when multiprocess protocol extensions are supported.
2554 Obtains additional operating system information
2558 Read or write additional signal information.
2560 * Removed remote protocol undocumented extension
2562 An undocumented extension to the remote protocol's `S' stop reply
2563 packet that permited the stub to pass a process id was removed.
2564 Remote servers should use the `T' stop reply packet instead.
2566 * GDB now supports multiple function calling conventions according to the
2567 DWARF-2 DW_AT_calling_convention function attribute.
2569 * The SH target utilizes the aforementioned change to distinguish between gcc
2570 and Renesas calling convention. It also adds the new CLI commands
2571 `set/show sh calling-convention'.
2573 * GDB can now read compressed debug sections, as produced by GNU gold
2574 with the --compress-debug-sections=zlib flag.
2576 * 64-bit core files are now supported on AIX.
2578 * Thread switching is now supported on Tru64.
2580 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2581 which will be allocated using malloc later in program execution.
2583 * The qXfer:libraries:read remote procotol packet now allows passing a
2584 list of section offsets.
2586 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2587 conditions handling signals delivered during attach or thread creation
2588 have also been fixed.
2590 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2591 From the user's standpoint, all unqualified instances of True and False
2592 are treated as the standard definitions, regardless of context.
2594 * GDB now parses C++ symbol and type names more flexibly. For
2597 template<typename T> class C { };
2600 GDB will now correctly handle all of:
2602 ptype C<char const *>
2603 ptype C<char const*>
2604 ptype C<const char *>
2605 ptype C<const char*>
2607 * New features in the GDB remote stub, gdbserver
2609 - The "--wrapper" command-line argument tells gdbserver to use a
2610 wrapper program to launch programs for debugging.
2612 - On PowerPC and S/390 targets, it is now possible to use a single
2613 gdbserver executable to debug both 32-bit and 64-bit programs.
2614 (This requires gdbserver itself to be built as a 64-bit executable.)
2616 - gdbserver uses the new noack protocol mode for TCP connections to
2617 reduce communications latency, if also supported and enabled in GDB.
2619 - Support for the sparc64-linux-gnu target is now included in
2622 - The amd64-linux build of gdbserver now supports debugging both
2623 32-bit and 64-bit programs.
2625 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2626 now support hardware watchpoints, and will use them automatically
2631 GDB now has support for scripting using Python. Whether this is
2632 available is determined at configure time.
2634 New GDB commands can now be written in Python.
2636 * Ada tasking support
2638 Ada tasks can now be inspected in GDB. The following commands have
2642 Print the list of Ada tasks.
2644 Print detailed information about task number N.
2646 Print the task number of the current task.
2648 Switch the context of debugging to task number N.
2650 * Support for user-defined prefixed commands. The "define" command can
2651 add new commands to existing prefixes, e.g. "target".
2653 * Multi-inferior, multi-process debugging.
2655 GDB now has generalized support for multi-inferior debugging. See
2656 "Debugging Multiple Inferiors" in the manual for more information.
2657 Although availability still depends on target support, the command
2658 set is more uniform now. The GNU/Linux specific multi-forks support
2659 has been migrated to this new framework. This implied some user
2660 visible changes; see "New commands" and also "Removed commands"
2663 * Target descriptions can now describe the target OS ABI. See the
2664 "Target Description Format" section in the user manual for more
2667 * Target descriptions can now describe "compatible" architectures
2668 to indicate that the target can execute applications for a different
2669 architecture in addition to those for the main target architecture.
2670 See the "Target Description Format" section in the user manual for
2673 * Multi-architecture debugging.
2675 GDB now includes general supports for debugging applications on
2676 hybrid systems that use more than one single processor architecture
2677 at the same time. Each such hybrid architecture still requires
2678 specific support to be added. The only hybrid architecture supported
2679 in this version of GDB is the Cell Broadband Engine.
2681 * GDB now supports integrated debugging of Cell/B.E. applications that
2682 use both the PPU and SPU architectures. To enable support for hybrid
2683 Cell/B.E. debugging, you need to configure GDB to support both the
2684 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2685 --enable-targets configure option.
2687 * Non-stop mode debugging.
2689 For some targets, GDB now supports an optional mode of operation in
2690 which you can examine stopped threads while other threads continue
2691 to execute freely. This is referred to as non-stop mode, with the
2692 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2693 section in the user manual for more information.
2695 To be able to support remote non-stop debugging, a remote stub needs
2696 to implement the non-stop mode remote protocol extensions, as
2697 described in the "Remote Non-Stop" section of the user manual. The
2698 GDB remote stub, gdbserver, has been adjusted to support these
2699 extensions on linux targets.
2701 * New commands (for set/show, see "New options" below)
2703 catch syscall [NAME(S) | NUMBER(S)]
2704 Catch system calls. Arguments, which should be names of system
2705 calls or their numbers, mean catch only those syscalls. Without
2706 arguments, every syscall will be caught. When the inferior issues
2707 any of the specified syscalls, GDB will stop and announce the system
2708 call, both when it is called and when its call returns. This
2709 feature is currently available with a native GDB running on the
2710 Linux Kernel, under the following architectures: x86, x86_64,
2711 PowerPC and PowerPC64.
2713 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2715 Search memory for a sequence of bytes.
2717 maint set python print-stack
2718 maint show python print-stack
2719 Show a stack trace when an error is encountered in a Python script.
2722 Invoke CODE by passing it to the Python interpreter.
2727 These allow macros to be defined, undefined, and listed
2731 Show operating system information about processes.
2734 List the inferiors currently under GDB's control.
2737 Switch focus to inferior number NUM.
2740 Detach from inferior number NUM.
2743 Kill inferior number NUM.
2747 set spu stop-on-load
2748 show spu stop-on-load
2749 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2751 set spu auto-flush-cache
2752 show spu auto-flush-cache
2753 Control whether to automatically flush the software-managed cache
2754 during Cell/B.E. debugging.
2756 set sh calling-convention
2757 show sh calling-convention
2758 Control the calling convention used when calling SH target functions.
2761 show debug timestamp
2762 Control display of timestamps with GDB debugging output.
2764 set disassemble-next-line
2765 show disassemble-next-line
2766 Control display of disassembled source lines or instructions when
2769 set remote noack-packet
2770 show remote noack-packet
2771 Set/show the use of remote protocol QStartNoAckMode packet. See above
2772 under "New remote packets."
2774 set remote query-attached-packet
2775 show remote query-attached-packet
2776 Control use of remote protocol `qAttached' (query-attached) packet.
2778 set remote read-siginfo-object
2779 show remote read-siginfo-object
2780 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2783 set remote write-siginfo-object
2784 show remote write-siginfo-object
2785 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2788 set remote reverse-continue
2789 show remote reverse-continue
2790 Control use of remote protocol 'bc' (reverse-continue) packet.
2792 set remote reverse-step
2793 show remote reverse-step
2794 Control use of remote protocol 'bs' (reverse-step) packet.
2796 set displaced-stepping
2797 show displaced-stepping
2798 Control displaced stepping mode. Displaced stepping is a way to
2799 single-step over breakpoints without removing them from the debuggee.
2800 Also known as "out-of-line single-stepping".
2803 show debug displaced
2804 Control display of debugging info for displaced stepping.
2806 maint set internal-error
2807 maint show internal-error
2808 Control what GDB does when an internal error is detected.
2810 maint set internal-warning
2811 maint show internal-warning
2812 Control what GDB does when an internal warning is detected.
2817 Use a wrapper program to launch programs for debugging.
2819 set multiple-symbols (all|ask|cancel)
2820 show multiple-symbols
2821 The value of this variable can be changed to adjust the debugger behavior
2822 when an expression or a breakpoint location contains an ambiguous symbol
2823 name (an overloaded function name, for instance).
2825 set breakpoint always-inserted
2826 show breakpoint always-inserted
2827 Keep breakpoints always inserted in the target, as opposed to inserting
2828 them when resuming the target, and removing them when the target stops.
2829 This option can improve debugger performance on slow remote targets.
2831 set arm fallback-mode (arm|thumb|auto)
2832 show arm fallback-mode
2833 set arm force-mode (arm|thumb|auto)
2835 These commands control how ARM GDB determines whether instructions
2836 are ARM or Thumb. The default for both settings is auto, which uses
2837 the current CPSR value for instructions without symbols; previous
2838 versions of GDB behaved as if "set arm fallback-mode arm".
2840 set disable-randomization
2841 show disable-randomization
2842 Standalone programs run with the virtual address space randomization enabled
2843 by default on some platforms. This option keeps the addresses stable across
2844 multiple debugging sessions.
2848 Control whether other threads are stopped or not when some thread hits
2853 Requests that asynchronous execution is enabled in the target, if available.
2854 In this case, it's possible to resume target in the background, and interact
2855 with GDB while the target is running. "show target-async" displays the
2856 current state of asynchronous execution of the target.
2858 set target-wide-charset
2859 show target-wide-charset
2860 The target-wide-charset is the name of the character set that GDB
2861 uses when printing characters whose type is wchar_t.
2863 set tcp auto-retry (on|off)
2865 set tcp connect-timeout
2866 show tcp connect-timeout
2867 These commands allow GDB to retry failed TCP connections to a remote stub
2868 with a specified timeout period; this is useful if the stub is launched
2869 in parallel with GDB but may not be ready to accept connections immediately.
2871 set libthread-db-search-path
2872 show libthread-db-search-path
2873 Control list of directories which GDB will search for appropriate
2876 set schedule-multiple (on|off)
2877 show schedule-multiple
2878 Allow GDB to resume all threads of all processes or only threads of
2879 the current process.
2883 Use more aggressive caching for accesses to the stack. This improves
2884 performance of remote debugging (particularly backtraces) without
2885 affecting correctness.
2887 set interactive-mode (on|off|auto)
2888 show interactive-mode
2889 Control whether GDB runs in interactive mode (on) or not (off).
2890 When in interactive mode, GDB waits for the user to answer all
2891 queries. Otherwise, GDB does not wait and assumes the default
2892 answer. When set to auto (the default), GDB determines which
2893 mode to use based on the stdin settings.
2898 For program forks, this is replaced by the new more generic `info
2899 inferiors' command. To list checkpoints, you can still use the
2900 `info checkpoints' command, which was an alias for the `info forks'
2904 Replaced by the new `inferior' command. To switch between
2905 checkpoints, you can still use the `restart' command, which was an
2906 alias for the `fork' command.
2909 This is removed, since some targets don't have a notion of
2910 processes. To switch between processes, you can still use the
2911 `inferior' command using GDB's own inferior number.
2914 For program forks, this is replaced by the new more generic `kill
2915 inferior' command. To delete a checkpoint, you can still use the
2916 `delete checkpoint' command, which was an alias for the `delete
2920 For program forks, this is replaced by the new more generic `detach
2921 inferior' command. To detach a checkpoint, you can still use the
2922 `detach checkpoint' command, which was an alias for the `detach
2925 * New native configurations
2927 x86/x86_64 Darwin i[34567]86-*-darwin*
2929 x86_64 MinGW x86_64-*-mingw*
2933 Lattice Mico32 lm32-*
2934 x86 DICOS i[34567]86-*-dicos*
2935 x86_64 DICOS x86_64-*-dicos*
2938 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2939 (mingw32ce) debugging.
2945 These commands were actually not implemented on any target.
2947 *** Changes in GDB 6.8
2949 * New native configurations
2951 NetBSD/hppa hppa*-*netbsd*
2952 Xtensa GNU/Linux xtensa*-*-linux*
2956 NetBSD/hppa hppa*-*-netbsd*
2957 Xtensa GNU/Lunux xtensa*-*-linux*
2959 * Change in command line behavior -- corefiles vs. process ids.
2961 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2962 attaching to process NUMBER fails, GDB no longer attempts to open a
2963 core file named NUMBER. Attaching to a program using the -c option
2964 is no longer supported. Instead, use the '-p' or '--pid' options.
2966 * GDB can now be built as a native debugger for debugging Windows x86
2967 (mingw32) Portable Executable (PE) programs.
2969 * Pending breakpoints no longer change their number when their address
2972 * GDB now supports breakpoints with multiple locations,
2973 including breakpoints on C++ constructors, inside C++ templates,
2974 and in inlined functions.
2976 * GDB's ability to debug optimized code has been improved. GDB more
2977 accurately identifies function bodies and lexical blocks that occupy
2978 more than one contiguous range of addresses.
2980 * Target descriptions can now describe registers for PowerPC.
2982 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2983 registers on PowerPC targets.
2985 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2986 targets even when the libthread_db library is not available.
2988 * The GDB remote stub, gdbserver, now supports the new file transfer
2989 commands (remote put, remote get, and remote delete).
2991 * The GDB remote stub, gdbserver, now supports run and attach in
2992 extended-remote mode.
2994 * hppa*64*-*-hpux11* target broken
2995 The debugger is unable to start a program and fails with the following
2996 error: "Error trying to get information about dynamic linker".
2997 The gdb-6.7 release is also affected.
2999 * GDB now supports the --enable-targets= configure option to allow
3000 building a single GDB executable that supports multiple remote
3001 target architectures.
3003 * GDB now supports debugging C and C++ programs which use the
3004 Decimal Floating Point extension. In addition, the PowerPC target
3005 now has a set of pseudo-registers to inspect decimal float values
3006 stored in two consecutive float registers.
3008 * The -break-insert MI command can optionally create pending
3011 * Improved support for debugging Ada
3012 Many improvements to the Ada language support have been made. These
3014 - Better support for Ada2005 interface types
3015 - Improved handling of arrays and slices in general
3016 - Better support for Taft-amendment types
3017 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3019 - Improved command completion in Ada
3022 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3027 set print frame-arguments (all|scalars|none)
3028 show print frame-arguments
3029 The value of this variable can be changed to control which argument
3030 values should be printed by the debugger when displaying a frame.
3035 Transfer files to and from a remote target, and delete remote files.
3042 Transfer files to and from a remote target, and delete remote files.
3044 * New remote packets
3051 Open, close, read, write, and delete files on the remote system.
3054 Attach to an existing process on the remote system, in extended-remote
3058 Run a new process on the remote system, in extended-remote mode.
3060 *** Changes in GDB 6.7
3062 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3063 bfd, libiberty and opcodes, as revealed by static analysis donated by
3064 Coverity, Inc. (http://scan.coverity.com).
3066 * When looking up multiply-defined global symbols, GDB will now prefer the
3067 symbol definition in the current shared library if it was built using the
3068 -Bsymbolic linker option.
3070 * When the Text User Interface (TUI) is not configured, GDB will now
3071 recognize the -tui command-line option and print a message that the TUI
3074 * The GDB remote stub, gdbserver, now has lower overhead for high
3075 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3077 * GDB for MIPS targets now autodetects whether a remote target provides
3078 32-bit or 64-bit register values.
3080 * Support for C++ member pointers has been improved.
3082 * GDB now understands XML target descriptions, which specify the
3083 target's overall architecture. GDB can read a description from
3084 a local file or over the remote serial protocol.
3086 * Vectors of single-byte data use a new integer type which is not
3087 automatically displayed as character or string data.
3089 * The /s format now works with the print command. It displays
3090 arrays of single-byte integers and pointers to single-byte integers
3093 * Target descriptions can now describe target-specific registers,
3094 for architectures which have implemented the support (currently
3095 only ARM, M68K, and MIPS).
3097 * GDB and the GDB remote stub, gdbserver, now support the XScale
3100 * The GDB remote stub, gdbserver, has been updated to support
3101 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3102 has been rewritten to use the standard GDB remote protocol.
3104 * GDB can now step into C++ functions which are called through thunks.
3106 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3108 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3109 layout. It also supports a TextSeg= and DataSeg= response when only
3110 segment base addresses (rather than offsets) are available.
3112 * The /i format now outputs any trailing branch delay slot instructions
3113 immediately following the last instruction within the count specified.
3115 * The GDB remote protocol "T" stop reply packet now supports a
3116 "library" response. Combined with the new "qXfer:libraries:read"
3117 packet, this response allows GDB to debug shared libraries on targets
3118 where the operating system manages the list of loaded libraries (e.g.
3119 Windows and SymbianOS).
3121 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3122 (DLLs) on Windows and Windows CE targets.
3124 * GDB now supports a faster verification that a .debug file matches its binary
3125 according to its build-id signature, if the signature is present.
3131 Enable or disable hardware flow control (RTS/CTS) on the serial port
3132 when debugging using remote targets.
3134 set mem inaccessible-by-default
3135 show mem inaccessible-by-default
3136 If the target supplies a memory map, for instance via the remote
3137 protocol's "qXfer:memory-map:read" packet, setting this variable
3138 prevents GDB from accessing memory outside the memory map. This
3139 is useful for targets with memory mapped registers or which react
3140 badly to accesses of unmapped address space.
3142 set breakpoint auto-hw
3143 show breakpoint auto-hw
3144 If the target supplies a memory map, for instance via the remote
3145 protocol's "qXfer:memory-map:read" packet, setting this variable
3146 lets GDB use hardware breakpoints automatically for memory regions
3147 where it can not use software breakpoints. This covers both the
3148 "break" command and internal breakpoints used for other commands
3149 including "next" and "finish".
3152 catch exception unhandled
3153 Stop the program execution when Ada exceptions are raised.
3156 Stop the program execution when an Ada assertion failed.
3160 Set an alternate system root for target files. This is a more
3161 general version of "set solib-absolute-prefix", which is now
3162 an alias to "set sysroot".
3165 Provide extended SPU facility status information. This set of
3166 commands is available only when debugging the Cell/B.E. SPU
3169 * New native configurations
3171 OpenBSD/sh sh*-*openbsd*
3174 unset tdesc filename
3176 Use the specified local file as an XML target description, and do
3177 not query the target for its built-in description.
3181 OpenBSD/sh sh*-*-openbsd*
3182 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3183 Toshiba Media Processor mep-elf
3185 * New remote packets
3188 Ignore the specified signals; pass them directly to the debugged program
3189 without stopping other threads or reporting them to GDB.
3191 qXfer:features:read:
3192 Read an XML target description from the target, which describes its
3197 Read or write contents of an spufs file on the target system. These
3198 packets are available only on the Cell/B.E. SPU architecture.
3200 qXfer:libraries:read:
3201 Report the loaded shared libraries. Combined with new "T" packet
3202 response, this packet allows GDB to debug shared libraries on
3203 targets where the operating system manages the list of loaded
3204 libraries (e.g. Windows and SymbianOS).
3208 Support for these obsolete configurations has been removed.
3216 i[34567]86-*-lynxos*
3217 i[34567]86-*-netware*
3218 i[34567]86-*-sco3.2v5*
3219 i[34567]86-*-sco3.2v4*
3221 i[34567]86-*-sysv4.2*
3224 i[34567]86-*-unixware2*
3225 i[34567]86-*-unixware*
3234 * Other removed features
3241 Various m68k-only ROM monitors.
3248 Various Renesas ROM monitors and debugging interfaces for SH and
3253 Support for a Macraigor serial interface to on-chip debugging.
3254 GDB does not directly support the newer parallel or USB
3259 A debug information format. The predecessor to DWARF 2 and
3260 DWARF 3, which are still supported.
3262 Support for the HP aCC compiler on HP-UX/PA-RISC
3264 SOM-encapsulated symbolic debugging information, automatic
3265 invocation of pxdb, and the aCC custom C++ ABI. This does not
3266 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3267 with aCC can still be debugged on an assembly level.
3269 MIPS ".pdr" sections
3271 A MIPS-specific format used to describe stack frame layout
3272 in debugging information.
3276 GDB could work with an older version of Guile to debug
3277 the interpreter and Scheme programs running in it.
3279 set mips stack-arg-size
3280 set mips saved-gpreg-size
3282 Use "set mips abi" to control parameter passing for MIPS.
3284 *** Changes in GDB 6.6
3289 Cell Broadband Engine SPU spu-elf
3291 * GDB can now be configured as a cross-debugger targeting native Windows
3292 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3293 running on a Windows system over TCP/IP to debug Windows programs.
3295 * The GDB remote stub, gdbserver, has been updated to support Windows and
3296 Cygwin debugging. Both single-threaded and multi-threaded programs are
3299 * The "set trust-readonly-sections" command works again. This command was
3300 broken in GDB 6.3, 6.4, and 6.5.
3302 * The "load" command now supports writing to flash memory, if the remote
3303 stub provides the required support.
3305 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3306 longer requires symbolic debug information (e.g. DWARF-2).
3311 unset substitute-path
3312 show substitute-path
3313 Manage a list of substitution rules that GDB uses to rewrite the name
3314 of the directories where the sources are located. This can be useful
3315 for instance when the sources were moved to a different location
3316 between compilation and debugging.
3320 Print each CLI command as it is executed. Each command is prefixed with
3321 a number of `+' symbols representing the nesting depth.
3322 The source command now has a `-v' option to enable the same feature.
3326 The ARM Demon monitor support (RDP protocol, "target rdp").
3328 Kernel Object Display, an embedded debugging feature which only worked with
3329 an obsolete version of Cisco IOS.
3331 The 'set download-write-size' and 'show download-write-size' commands.
3333 * New remote packets
3336 Tell a stub about GDB client features, and request remote target features.
3337 The first feature implemented is PacketSize, which allows the target to
3338 specify the size of packets it can handle - to minimize the number of
3339 packets required and improve performance when connected to a remote
3343 Fetch an OS auxilliary vector from the remote stub. This packet is a
3344 more efficient replacement for qPart:auxv:read.
3346 qXfer:memory-map:read:
3347 Fetch a memory map from the remote stub, including information about
3348 RAM, ROM, and flash memory devices.
3353 Erase and program a flash memory device.
3355 * Removed remote packets
3358 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3359 used it, and only gdbserver implemented it.
3361 *** Changes in GDB 6.5
3365 Renesas M32C/M16C m32c-elf
3367 Morpho Technologies ms1 ms1-elf
3371 init-if-undefined Initialize a convenience variable, but
3372 only if it doesn't already have a value.
3374 The following commands are presently only implemented for native GNU/Linux:
3376 checkpoint Save a snapshot of the program state.
3378 restart <n> Return the program state to a
3379 previously saved state.
3381 info checkpoints List currently saved checkpoints.
3383 delete-checkpoint <n> Delete a previously saved checkpoint.
3385 set|show detach-on-fork Tell gdb whether to detach from a newly
3386 forked process, or to keep debugging it.
3388 info forks List forks of the user program that
3389 are available to be debugged.
3391 fork <n> Switch to debugging one of several
3392 forks of the user program that are
3393 available to be debugged.
3395 delete-fork <n> Delete a fork from the list of forks
3396 that are available to be debugged (and
3397 kill the forked process).
3399 detach-fork <n> Delete a fork from the list of forks
3400 that are available to be debugged (and
3401 allow the process to continue).
3405 Morpho Technologies ms2 ms1-elf
3407 * Improved Windows host support
3409 GDB now builds as a cross debugger hosted on i686-mingw32, including
3410 native console support, and remote communications using either
3411 network sockets or serial ports.
3413 * Improved Modula-2 language support
3415 GDB can now print most types in the Modula-2 syntax. This includes:
3416 basic types, set types, record types, enumerated types, range types,
3417 pointer types and ARRAY types. Procedure var parameters are correctly
3418 printed and hexadecimal addresses and character constants are also
3419 written in the Modula-2 syntax. Best results can be obtained by using
3420 GNU Modula-2 together with the -gdwarf-2 command line option.
3424 The ARM rdi-share module.
3426 The Netware NLM debug server.
3428 *** Changes in GDB 6.4
3430 * New native configurations
3432 OpenBSD/arm arm*-*-openbsd*
3433 OpenBSD/mips64 mips64-*-openbsd*
3437 Morpho Technologies ms1 ms1-elf
3439 * New command line options
3441 --batch-silent As for --batch, but totally silent.
3442 --return-child-result The debugger will exist with the same value
3443 the child (debugged) program exited with.
3444 --eval-command COMMAND, -ex COMMAND
3445 Execute a single GDB CLI command. This may be
3446 specified multiple times and in conjunction
3447 with the --command (-x) option.
3449 * Deprecated commands removed
3451 The following commands, that were deprecated in 2000, have been
3455 set|show arm disassembly-flavor set|show arm disassembler
3456 othernames set arm disassembler
3457 set|show remotedebug set|show debug remote
3458 set|show archdebug set|show debug arch
3459 set|show eventdebug set|show debug event
3462 * New BSD user-level threads support
3464 It is now possible to debug programs using the user-level threads
3465 library on OpenBSD and FreeBSD. Currently supported (target)
3468 FreeBSD/amd64 x86_64-*-freebsd*
3469 FreeBSD/i386 i386-*-freebsd*
3470 OpenBSD/i386 i386-*-openbsd*
3472 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3473 are not yet supported.
3475 * New support for Matsushita MN10300 w/sim added
3476 (Work in progress). mn10300-elf.
3478 * REMOVED configurations and files
3480 VxWorks and the XDR protocol *-*-vxworks
3481 Motorola MCORE mcore-*-*
3482 National Semiconductor NS32000 ns32k-*-*
3484 * New "set print array-indexes" command
3486 After turning this setting "on", GDB prints the index of each element
3487 when displaying arrays. The default is "off" to preserve the previous
3490 * VAX floating point support
3492 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3494 * User-defined command support
3496 In addition to using $arg0..$arg9 for argument passing, it is now possible
3497 to use $argc to determine now many arguments have been passed. See the
3498 section on user-defined commands in the user manual for more information.
3500 *** Changes in GDB 6.3:
3502 * New command line option
3504 GDB now accepts -l followed by a number to set the timeout for remote
3507 * GDB works with GCC -feliminate-dwarf2-dups
3509 GDB now supports a more compact representation of DWARF-2 debug
3510 information using DW_FORM_ref_addr references. These are produced
3511 by GCC with the option -feliminate-dwarf2-dups and also by some
3512 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3513 to use -feliminate-dwarf2-dups.
3515 * Internationalization
3517 When supported by the host system, GDB will be built with
3518 internationalization (libintl). The task of marking up the sources is
3519 continued, we're looking forward to our first translation.
3523 Initial support for debugging programs compiled with the GNAT
3524 implementation of the Ada programming language has been integrated
3525 into GDB. In this release, support is limited to expression evaluation.
3527 * New native configurations
3529 GNU/Linux/m32r m32r-*-linux-gnu
3533 GDB's remote protocol now includes support for the 'p' packet. This
3534 packet is used to fetch individual registers from a remote inferior.
3536 * END-OF-LIFE registers[] compatibility module
3538 GDB's internal register infrastructure has been completely rewritten.
3539 The new infrastructure making possible the implementation of key new
3540 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3543 GDB 6.3 will be the last release to include the the registers[]
3544 compatibility module that allowed out-of-date configurations to
3545 continue to work. This change directly impacts the following
3555 powerpc bdm protocol
3557 Unless there is activity to revive these configurations, they will be
3558 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3560 * OBSOLETE configurations and files
3562 Configurations that have been declared obsolete in this release have
3563 been commented out. Unless there is activity to revive these
3564 configurations, the next release of GDB will have their sources
3565 permanently REMOVED.
3574 *** Changes in GDB 6.2.1:
3576 * MIPS `break main; run' gave an heuristic-fence-post warning
3578 When attempting to run even a simple program, a warning about
3579 heuristic-fence-post being hit would be reported. This problem has
3582 * MIPS IRIX 'long double' crashed GDB
3584 When examining a long double variable, GDB would get a segmentation
3585 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3586 IRIX long double values).
3590 A bug in the VAX stack code was causing problems with the "next"
3591 command. This problem has been fixed.
3593 *** Changes in GDB 6.2:
3595 * Fix for ``many threads''
3597 On GNU/Linux systems that use the NPTL threads library, a program
3598 rapidly creating and deleting threads would confuse GDB leading to the
3601 ptrace: No such process.
3602 thread_db_get_info: cannot get thread info: generic error
3604 This problem has been fixed.
3606 * "-async" and "-noasync" options removed.
3608 Support for the broken "-noasync" option has been removed (it caused
3611 * New ``start'' command.
3613 This command runs the program until the begining of the main procedure.
3615 * New BSD Kernel Data Access Library (libkvm) interface
3617 Using ``target kvm'' it is now possible to debug kernel core dumps and
3618 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3619 platforms. Currently supported (native-only) configurations are:
3621 FreeBSD/amd64 x86_64-*-freebsd*
3622 FreeBSD/i386 i?86-*-freebsd*
3623 NetBSD/i386 i?86-*-netbsd*
3624 NetBSD/m68k m68*-*-netbsd*
3625 NetBSD/sparc sparc-*-netbsd*
3626 OpenBSD/amd64 x86_64-*-openbsd*
3627 OpenBSD/i386 i?86-*-openbsd*
3628 OpenBSD/m68k m68*-openbsd*
3629 OpenBSD/sparc sparc-*-openbsd*
3631 * Signal trampoline code overhauled
3633 Many generic problems with GDB's signal handling code have been fixed.
3634 These include: backtraces through non-contiguous stacks; recognition
3635 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3636 call; backtrace through a signal trampoline; step into and out of
3637 signal handlers; and single-stepping in the signal trampoline.
3639 Please note that kernel bugs are a limiting factor here. These
3640 features have been shown to work on an s390 GNU/Linux system that
3641 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3643 * Cygwin support for DWARF 2 added.
3645 * New native configurations
3647 GNU/Linux/hppa hppa*-*-linux*
3648 OpenBSD/hppa hppa*-*-openbsd*
3649 OpenBSD/m68k m68*-*-openbsd*
3650 OpenBSD/m88k m88*-*-openbsd*
3651 OpenBSD/powerpc powerpc-*-openbsd*
3652 NetBSD/vax vax-*-netbsd*
3653 OpenBSD/vax vax-*-openbsd*
3655 * END-OF-LIFE frame compatibility module
3657 GDB's internal frame infrastructure has been completely rewritten.
3658 The new infrastructure making it possible to support key new features
3659 including DWARF 2 Call Frame Information. To aid in the task of
3660 migrating old configurations to this new infrastructure, a
3661 compatibility module, that allowed old configurations to continue to
3662 work, was also included.
3664 GDB 6.2 will be the last release to include this frame compatibility
3665 module. This change directly impacts the following configurations:
3675 Unless there is activity to revive these configurations, they will be
3676 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3678 * REMOVED configurations and files
3680 Sun 3, running SunOS 3 m68*-*-sunos3*
3681 Sun 3, running SunOS 4 m68*-*-sunos4*
3682 Sun 2, running SunOS 3 m68000-*-sunos3*
3683 Sun 2, running SunOS 4 m68000-*-sunos4*
3684 Motorola 680x0 running LynxOS m68*-*-lynxos*
3685 AT&T 3b1/Unix pc m68*-att-*
3686 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3687 decstation mips-dec-* mips-little-*
3688 riscos mips-*-riscos* mips-*-sysv*
3689 sonymips mips-sony-*
3690 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3692 *** Changes in GDB 6.1.1:
3694 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3696 The TUI (Text-mode User Interface) is now built as part of a default
3697 GDB configuration. It is enabled by either selecting the TUI with the
3698 command line option "-i=tui" or by running the separate "gdbtui"
3699 program. For more information on the TUI, see the manual "Debugging
3702 * Pending breakpoint support (also included in GDB 6.1)
3704 Support has been added to allow you to specify breakpoints in shared
3705 libraries that have not yet been loaded. If a breakpoint location
3706 cannot be found, and the "breakpoint pending" option is set to auto,
3707 GDB queries you if you wish to make the breakpoint pending on a future
3708 shared-library load. If and when GDB resolves the breakpoint symbol,
3709 the pending breakpoint is removed as one or more regular breakpoints
3712 Pending breakpoints are very useful for GCJ Java debugging.
3714 * Fixed ISO-C build problems
3716 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3717 non ISO-C code that stopped them being built using a more strict ISO-C
3718 compiler (e.g., IBM's C compiler).
3720 * Fixed build problem on IRIX 5
3722 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3723 wasn't able to compile compile on an IRIX 5 system.
3725 * Added execute permission to gdb/gdbserver/configure
3727 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3728 permission. This bug would cause configure to fail on a number of
3729 systems (Solaris, IRIX). Ref: server/519.
3731 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3733 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3734 has been updated to use constant array sizes.
3736 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3738 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3739 its generated DWARF Call Frame Info. This encoding was causing GDB to
3740 panic, that panic has been fixed. Ref: gdb/1628.
3742 * Fixed a problem when examining parameters in shared library code.
3744 When examining parameters in optimized shared library code generated
3745 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3746 not available''. GDB now correctly displays the variable's value.
3748 *** Changes in GDB 6.1:
3750 * Removed --with-mmalloc
3752 Support for the mmalloc memory manager has been removed, as it
3753 conflicted with the internal gdb byte cache.
3755 * Changes in AMD64 configurations
3757 The AMD64 target now includes the %cs and %ss registers. As a result
3758 the AMD64 remote protocol has changed; this affects the floating-point
3759 and SSE registers. If you rely on those registers for your debugging,
3760 you should upgrade gdbserver on the remote side.
3762 * Revised SPARC target
3764 The SPARC target has been completely revised, incorporating the
3765 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3766 support for LynxOS and SunOS 4 has been dropped. Calling functions
3767 from within GDB on operating systems with a non-executable stack
3768 (Solaris, OpenBSD) now works.
3772 GDB has a new C++ demangler which does a better job on the mangled
3773 names generated by current versions of g++. It also runs faster, so
3774 with this and other changes gdb should now start faster on large C++
3777 * DWARF 2 Location Expressions
3779 GDB support for location expressions has been extended to support function
3780 arguments and frame bases. Older versions of GDB could crash when they
3783 * C++ nested types and namespaces
3785 GDB's support for nested types and namespaces in C++ has been
3786 improved, especially if you use the DWARF 2 debugging format. (This
3787 is the default for recent versions of GCC on most platforms.)
3788 Specifically, if you have a class "Inner" defined within a class or
3789 namespace "Outer", then GDB realizes that the class's name is
3790 "Outer::Inner", not simply "Inner". This should greatly reduce the
3791 frequency of complaints about not finding RTTI symbols. In addition,
3792 if you are stopped at inside of a function defined within a namespace,
3793 GDB modifies its name lookup accordingly.
3795 * New native configurations
3797 NetBSD/amd64 x86_64-*-netbsd*
3798 OpenBSD/amd64 x86_64-*-openbsd*
3799 OpenBSD/alpha alpha*-*-openbsd*
3800 OpenBSD/sparc sparc-*-openbsd*
3801 OpenBSD/sparc64 sparc64-*-openbsd*
3803 * New debugging protocols
3805 M32R with SDI protocol m32r-*-elf*
3807 * "set prompt-escape-char" command deleted.
3809 The command "set prompt-escape-char" has been deleted. This command,
3810 and its very obscure effet on GDB's prompt, was never documented,
3811 tested, nor mentioned in the NEWS file.
3813 * OBSOLETE configurations and files
3815 Configurations that have been declared obsolete in this release have
3816 been commented out. Unless there is activity to revive these
3817 configurations, the next release of GDB will have their sources
3818 permanently REMOVED.
3820 Sun 3, running SunOS 3 m68*-*-sunos3*
3821 Sun 3, running SunOS 4 m68*-*-sunos4*
3822 Sun 2, running SunOS 3 m68000-*-sunos3*
3823 Sun 2, running SunOS 4 m68000-*-sunos4*
3824 Motorola 680x0 running LynxOS m68*-*-lynxos*
3825 AT&T 3b1/Unix pc m68*-att-*
3826 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3827 decstation mips-dec-* mips-little-*
3828 riscos mips-*-riscos* mips-*-sysv*
3829 sonymips mips-sony-*
3830 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3832 * REMOVED configurations and files
3834 SGI Irix-4.x mips-sgi-irix4 or iris4
3835 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3836 Z8000 simulator z8k-zilog-none or z8ksim
3837 Matsushita MN10200 w/simulator mn10200-*-*
3838 H8/500 simulator h8500-hitachi-hms or h8500hms
3839 HP/PA running BSD hppa*-*-bsd*
3840 HP/PA running OSF/1 hppa*-*-osf*
3841 HP/PA Pro target hppa*-*-pro*
3842 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3843 386BSD i[3456]86-*-bsd*
3844 Sequent family i[3456]86-sequent-sysv4*
3845 i[3456]86-sequent-sysv*
3846 i[3456]86-sequent-bsd*
3847 SPARC running LynxOS sparc-*-lynxos*
3848 SPARC running SunOS 4 sparc-*-sunos4*
3849 Tsqware Sparclet sparclet-*-*
3850 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3852 *** Changes in GDB 6.0:
3856 Support for debugging the Objective-C programming language has been
3857 integrated into GDB.
3859 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3861 DWARF 2's Call Frame Information makes available compiler generated
3862 information that more exactly describes the program's run-time stack.
3863 By using this information, GDB is able to provide more robust stack
3866 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3867 have been updated to use a new backtrace mechanism which includes
3868 DWARF 2 CFI support.
3872 GDB's remote protocol has been extended to include support for hosted
3873 file I/O (where the remote target uses GDB's file system). See GDB's
3874 remote protocol documentation for details.
3876 * All targets using the new architecture framework.
3878 All of GDB's targets have been updated to use the new internal
3879 architecture framework. The way is now open for future GDB releases
3880 to include cross-architecture native debugging support (i386 on amd64,
3883 * GNU/Linux's Thread Local Storage (TLS)
3885 GDB now includes support for for the GNU/Linux implementation of
3886 per-thread variables.
3888 * GNU/Linux's Native POSIX Thread Library (NPTL)
3890 GDB's thread code has been updated to work with either the new
3891 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3893 * Separate debug info.
3895 GDB, in conjunction with BINUTILS, now supports a mechanism for
3896 automatically loading debug information from a separate file. Instead
3897 of shipping full debug and non-debug versions of system libraries,
3898 system integrators can now instead ship just the stripped libraries
3899 and optional debug files.
3901 * DWARF 2 Location Expressions
3903 DWARF 2 Location Expressions allow the compiler to more completely
3904 describe the location of variables (even in optimized code) to the
3907 GDB now includes preliminary support for location expressions (support
3908 for DW_OP_piece is still missing).
3912 A number of long standing bugs that caused GDB to die while starting a
3913 Java application have been fixed. GDB's Java support is now
3914 considered "useable".
3916 * GNU/Linux support for fork, vfork, and exec.
3918 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3919 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3922 * GDB supports logging output to a file
3924 There are two new commands, "set logging" and "show logging", which can be
3925 used to capture GDB's output to a file.
3927 * The meaning of "detach" has changed for gdbserver
3929 The "detach" command will now resume the application, as documented. To
3930 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3933 * d10v, m68hc11 `regs' command deprecated
3935 The `info registers' command has been updated so that it displays the
3936 registers using a format identical to the old `regs' command.
3940 A new command, "maint set profile on/off", has been added. This command can
3941 be used to enable or disable profiling while running GDB, to profile a
3942 session or a set of commands. In addition there is a new configure switch,
3943 "--enable-profiling", which will cause GDB to be compiled with profiling
3944 data, for more informative profiling results.
3946 * Default MI syntax changed to "mi2".
3948 The default MI (machine interface) syntax, enabled by the command line
3949 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3950 "mi1", can be enabled by specifying the option "-i=mi1".
3952 Support for the original "mi0" syntax (included in GDB 5.0) has been
3955 Fix for gdb/192: removed extraneous space when displaying frame level.
3956 Fix for gdb/672: update changelist is now output in mi list format.
3957 Fix for gdb/702: a -var-assign that updates the value now shows up
3958 in a subsequent -var-update.
3960 * New native configurations.
3962 FreeBSD/amd64 x86_64-*-freebsd*
3964 * Multi-arched targets.
3966 HP/PA HPUX11 hppa*-*-hpux*
3967 Renesas M32R/D w/simulator m32r-*-elf*
3969 * OBSOLETE configurations and files
3971 Configurations that have been declared obsolete in this release have
3972 been commented out. Unless there is activity to revive these
3973 configurations, the next release of GDB will have their sources
3974 permanently REMOVED.
3976 Z8000 simulator z8k-zilog-none or z8ksim
3977 Matsushita MN10200 w/simulator mn10200-*-*
3978 H8/500 simulator h8500-hitachi-hms or h8500hms
3979 HP/PA running BSD hppa*-*-bsd*
3980 HP/PA running OSF/1 hppa*-*-osf*
3981 HP/PA Pro target hppa*-*-pro*
3982 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3983 Sequent family i[3456]86-sequent-sysv4*
3984 i[3456]86-sequent-sysv*
3985 i[3456]86-sequent-bsd*
3986 Tsqware Sparclet sparclet-*-*
3987 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3989 * REMOVED configurations and files
3992 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3993 IBM AIX PS/2 i[3456]86-*-aix
3994 i386 running Mach 3.0 i[3456]86-*-mach3*
3995 i386 running Mach i[3456]86-*-mach*
3996 i386 running OSF/1 i[3456]86-*osf1mk*
3997 HP/Apollo 68k Family m68*-apollo*-sysv*,
3999 m68*-hp-bsd*, m68*-hp-hpux*
4000 Argonaut Risc Chip (ARC) arc-*-*
4001 Mitsubishi D30V d30v-*-*
4002 Fujitsu FR30 fr30-*-elf*
4003 OS/9000 i[34]86-*-os9k
4004 I960 with MON960 i960-*-coff
4006 * MIPS $fp behavior changed
4008 The convenience variable $fp, for the MIPS, now consistently returns
4009 the address of the current frame's base. Previously, depending on the
4010 context, $fp could refer to either $sp or the current frame's base
4011 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4012 The GNU Source-Level Debugger''.
4014 *** Changes in GDB 5.3:
4016 * GNU/Linux shared library multi-threaded performance improved.
4018 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4019 `/proc', in preference to `ptrace' for memory reads. This may result
4020 in an improvement in the start-up time of multi-threaded, shared
4021 library applications when run under GDB. One GDB user writes: ``loads
4022 shared libs like mad''.
4024 * ``gdbserver'' now supports multi-threaded applications on some targets
4026 Support for debugging multi-threaded applications which use
4027 the GNU/Linux LinuxThreads package has been added for
4028 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4029 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4031 * GDB now supports C/C++ preprocessor macros.
4033 GDB now expands preprocessor macro invocations in C/C++ expressions,
4034 and provides various commands for showing macro definitions and how
4037 The new command `macro expand EXPRESSION' expands any macro
4038 invocations in expression, and shows the result.
4040 The new command `show macro MACRO-NAME' shows the definition of the
4041 macro named MACRO-NAME, and where it was defined.
4043 Most compilers don't include information about macros in the debugging
4044 information by default. In GCC 3.1, for example, you need to compile
4045 your program with the options `-gdwarf-2 -g3'. If the macro
4046 information is present in the executable, GDB will read it.
4048 * Multi-arched targets.
4050 DEC Alpha (partial) alpha*-*-*
4051 DEC VAX (partial) vax-*-*
4053 National Semiconductor NS32000 (partial) ns32k-*-*
4054 Motorola 68000 (partial) m68k-*-*
4055 Motorola MCORE mcore-*-*
4059 Fujitsu FRV architecture added by Red Hat frv*-*-*
4062 * New native configurations
4064 Alpha NetBSD alpha*-*-netbsd*
4065 SH NetBSD sh*-*-netbsdelf*
4066 MIPS NetBSD mips*-*-netbsd*
4067 UltraSPARC NetBSD sparc64-*-netbsd*
4069 * OBSOLETE configurations and files
4071 Configurations that have been declared obsolete in this release have
4072 been commented out. Unless there is activity to revive these
4073 configurations, the next release of GDB will have their sources
4074 permanently REMOVED.
4076 Mitsubishi D30V d30v-*-*
4077 OS/9000 i[34]86-*-os9k
4078 IBM AIX PS/2 i[3456]86-*-aix
4079 Fujitsu FR30 fr30-*-elf*
4080 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4081 Argonaut Risc Chip (ARC) arc-*-*
4082 i386 running Mach 3.0 i[3456]86-*-mach3*
4083 i386 running Mach i[3456]86-*-mach*
4084 i386 running OSF/1 i[3456]86-*osf1mk*
4085 HP/Apollo 68k Family m68*-apollo*-sysv*,
4087 m68*-hp-bsd*, m68*-hp-hpux*
4088 I960 with MON960 i960-*-coff
4090 * OBSOLETE languages
4092 CHILL, a Pascal like language used by telecommunications companies.
4094 * REMOVED configurations and files
4096 AMD 29k family via UDI a29k-amd-udi, udi29k
4097 A29K VxWorks a29k-*-vxworks
4098 AMD 29000 embedded, using EBMON a29k-none-none
4099 AMD 29000 embedded with COFF a29k-none-coff
4100 AMD 29000 embedded with a.out a29k-none-aout
4102 testsuite/gdb.hp/gdb.threads-hp/ directory
4104 * New command "set max-user-call-depth <nnn>"
4106 This command allows the user to limit the call depth of user-defined
4107 commands. The default is 1024.
4109 * Changes in FreeBSD/i386 native debugging.
4111 Support for the "generate-core-file" has been added.
4113 * New commands "dump", "append", and "restore".
4115 These commands allow data to be copied from target memory
4116 to a bfd-format or binary file (dump and append), and back
4117 from a file into memory (restore).
4119 * Improved "next/step" support on multi-processor Alpha Tru64.
4121 The previous single-step mechanism could cause unpredictable problems,
4122 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4123 of a software single-step mechanism prevents this.
4125 *** Changes in GDB 5.2.1:
4133 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4134 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4135 Fix, by Joel Brobecker imported from mainline.
4137 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4138 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4139 Fix, by Fred Fish, imported from mainline.
4141 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4142 Surprisingly enough, it works now.
4143 By Michal Ludvig, imported from mainline.
4145 i386 hardware watchpoint support:
4146 avoid misses on second run for some targets.
4147 By Pierre Muller, imported from mainline.
4149 *** Changes in GDB 5.2:
4151 * New command "set trust-readonly-sections on[off]".
4153 This command is a hint that tells gdb that read-only sections
4154 really are read-only (ie. that their contents will not change).
4155 In this mode, gdb will go to the object file rather than the
4156 target to read memory from read-only sections (such as ".text").
4157 This can be a significant performance improvement on some
4158 (notably embedded) targets.
4160 * New command "generate-core-file" (or "gcore").
4162 This new gdb command allows the user to drop a core file of the child
4163 process state at any time. So far it's been implemented only for
4164 GNU/Linux and Solaris, but should be relatively easily ported to other
4165 hosts. Argument is core file name (defaults to core.<pid>).
4167 * New command line option
4169 GDB now accepts --pid or -p followed by a process id.
4171 * Change in command line behavior -- corefiles vs. process ids.
4173 There is a subtle behavior in the way in which GDB handles
4174 command line arguments. The first non-flag argument is always
4175 a program to debug, but the second non-flag argument may either
4176 be a corefile or a process id. Previously, GDB would attempt to
4177 open the second argument as a corefile, and if that failed, would
4178 issue a superfluous error message and then attempt to attach it as
4179 a process. Now, if the second argument begins with a non-digit,
4180 it will be treated as a corefile. If it begins with a digit,
4181 GDB will attempt to attach it as a process, and if no such process
4182 is found, will then attempt to open it as a corefile.
4184 * Changes in ARM configurations.
4186 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4187 configuration is fully multi-arch.
4189 * New native configurations
4191 ARM NetBSD arm*-*-netbsd*
4192 x86 OpenBSD i[3456]86-*-openbsd*
4193 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4194 Sparc64 running FreeBSD sparc64-*-freebsd*
4198 Sanyo XStormy16 xstormy16-elf
4200 * OBSOLETE configurations and files
4202 Configurations that have been declared obsolete in this release have
4203 been commented out. Unless there is activity to revive these
4204 configurations, the next release of GDB will have their sources
4205 permanently REMOVED.
4207 AMD 29k family via UDI a29k-amd-udi, udi29k
4208 A29K VxWorks a29k-*-vxworks
4209 AMD 29000 embedded, using EBMON a29k-none-none
4210 AMD 29000 embedded with COFF a29k-none-coff
4211 AMD 29000 embedded with a.out a29k-none-aout
4213 testsuite/gdb.hp/gdb.threads-hp/ directory
4215 * REMOVED configurations and files
4217 TI TMS320C80 tic80-*-*
4219 PowerPC Solaris powerpcle-*-solaris*
4220 PowerPC Windows NT powerpcle-*-cygwin32
4221 PowerPC Netware powerpc-*-netware*
4222 Harris/CXUX m88k m88*-harris-cxux*
4223 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4224 ns32k-utek-sysv* ns32k-utek-*
4225 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4226 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4227 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4228 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4229 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4231 * Changes to command line processing
4233 The new `--args' feature can be used to specify command-line arguments
4234 for the inferior from gdb's command line.
4236 * Changes to key bindings
4238 There is a new `operate-and-get-next' function bound to `C-o'.
4240 *** Changes in GDB 5.1.1
4242 Fix compile problem on DJGPP.
4244 Fix a problem with floating-point registers on the i386 being
4247 Fix to stop GDB crashing on .debug_str debug info.
4249 Numerous documentation fixes.
4251 Numerous testsuite fixes.
4253 *** Changes in GDB 5.1:
4255 * New native configurations
4257 Alpha FreeBSD alpha*-*-freebsd*
4258 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4259 MIPS GNU/Linux mips*-*-linux*
4260 MIPS SGI Irix 6.x mips*-sgi-irix6*
4261 ia64 AIX ia64-*-aix*
4262 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4266 Motorola 68HC11 and 68HC12 m68hc11-elf
4268 UltraSparc running GNU/Linux sparc64-*-linux*
4270 * OBSOLETE configurations and files
4272 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4273 Harris/CXUX m88k m88*-harris-cxux*
4274 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4275 ns32k-utek-sysv* ns32k-utek-*
4276 TI TMS320C80 tic80-*-*
4278 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4279 PowerPC Solaris powerpcle-*-solaris*
4280 PowerPC Windows NT powerpcle-*-cygwin32
4281 PowerPC Netware powerpc-*-netware*
4282 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4283 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4284 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4285 Apple Macintosh (MPW) host N/A
4287 stuff.c (Program to stuff files into a specially prepared space in kdb)
4288 kdb-start.c (Main loop for the standalone kernel debugger)
4290 Configurations that have been declared obsolete in this release have
4291 been commented out. Unless there is activity to revive these
4292 configurations, the next release of GDB will have their sources
4293 permanently REMOVED.
4295 * REMOVED configurations and files
4297 Altos 3068 m68*-altos-*
4298 Convex c1-*-*, c2-*-*
4300 ARM RISCix arm-*-* (as host)
4304 * GDB has been converted to ISO C.
4306 GDB's source code has been converted to ISO C. In particular, the
4307 sources are fully protoized, and rely on standard headers being
4312 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4314 * The MI enabled by default.
4316 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4317 revised and enabled by default. Packages which use GDB as a debugging
4318 engine behind a UI or another front end are encouraged to switch to
4319 using the GDB/MI interface, instead of the old annotations interface
4320 which is now deprecated.
4322 * Support for debugging Pascal programs.
4324 GDB now includes support for debugging Pascal programs. The following
4325 main features are supported:
4327 - Pascal-specific data types such as sets;
4329 - automatic recognition of Pascal sources based on file-name
4332 - Pascal-style display of data types, variables, and functions;
4334 - a Pascal expression parser.
4336 However, some important features are not yet supported.
4338 - Pascal string operations are not supported at all;
4340 - there are some problems with boolean types;
4342 - Pascal type hexadecimal constants are not supported
4343 because they conflict with the internal variables format;
4345 - support for Pascal objects and classes is not full yet;
4347 - unlike Pascal, GDB is case-sensitive for symbol names.
4349 * Changes in completion.
4351 Commands such as `shell', `run' and `set args', which pass arguments
4352 to inferior programs, now complete on file names, similar to what
4353 users expect at the shell prompt.
4355 Commands which accept locations, such as `disassemble', `print',
4356 `breakpoint', `until', etc. now complete on filenames as well as
4357 program symbols. Thus, if you type "break foob TAB", and the source
4358 files linked into the programs include `foobar.c', that file name will
4359 be one of the candidates for completion. However, file names are not
4360 considered for completion after you typed a colon that delimits a file
4361 name from a name of a function in that file, as in "break foo.c:bar".
4363 `set demangle-style' completes on available demangling styles.
4365 * New platform-independent commands:
4367 It is now possible to define a post-hook for a command as well as a
4368 hook that runs before the command. For more details, see the
4369 documentation of `hookpost' in the GDB manual.
4371 * Changes in GNU/Linux native debugging.
4373 Support for debugging multi-threaded programs has been completely
4374 revised for all platforms except m68k and sparc. You can now debug as
4375 many threads as your system allows you to have.
4377 Attach/detach is supported for multi-threaded programs.
4379 Support for SSE registers was added for x86. This doesn't work for
4380 multi-threaded programs though.
4382 * Changes in MIPS configurations.
4384 Multi-arch support is enabled for all MIPS configurations.
4386 GDB can now be built as native debugger on SGI Irix 6.x systems for
4387 debugging n32 executables. (Debugging 64-bit executables is not yet
4390 * Unified support for hardware watchpoints in all x86 configurations.
4392 Most (if not all) native x86 configurations support hardware-assisted
4393 breakpoints and watchpoints in a unified manner. This support
4394 implements debug register sharing between watchpoints, which allows to
4395 put a virtually infinite number of watchpoints on the same address,
4396 and also supports watching regions up to 16 bytes with several debug
4399 The new maintenance command `maintenance show-debug-regs' toggles
4400 debugging print-outs in functions that insert, remove, and test
4401 watchpoints and hardware breakpoints.
4403 * Changes in the DJGPP native configuration.
4405 New command ``info dos sysinfo'' displays assorted information about
4406 the CPU, OS, memory, and DPMI server.
4408 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4409 display information about segment descriptors stored in GDT, LDT, and
4412 New commands ``info dos pde'' and ``info dos pte'' display entries
4413 from Page Directory and Page Tables (for now works with CWSDPMI only).
4414 New command ``info dos address-pte'' displays the Page Table entry for
4415 a given linear address.
4417 GDB can now pass command lines longer than 126 characters to the
4418 program being debugged (requires an update to the libdbg.a library
4419 which is part of the DJGPP development kit).
4421 DWARF2 debug info is now supported.
4423 It is now possible to `step' and `next' through calls to `longjmp'.
4425 * Changes in documentation.
4427 All GDB documentation was converted to GFDL, the GNU Free
4428 Documentation License.
4430 Tracepoints-related commands are now fully documented in the GDB
4433 TUI, the Text-mode User Interface, is now documented in the manual.
4435 Tracepoints-related commands are now fully documented in the GDB
4438 The "GDB Internals" manual now has an index. It also includes
4439 documentation of `ui_out' functions, GDB coding standards, x86
4440 hardware watchpoints, and memory region attributes.
4442 * GDB's version number moved to ``version.in''
4444 The Makefile variable VERSION has been replaced by the file
4445 ``version.in''. People creating GDB distributions should update the
4446 contents of this file.
4450 GUD support is now a standard part of the EMACS distribution.
4452 *** Changes in GDB 5.0:
4454 * Improved support for debugging FP programs on x86 targets
4456 Unified and much-improved support for debugging floating-point
4457 programs on all x86 targets. In particular, ``info float'' now
4458 displays the FP registers in the same format on all x86 targets, with
4459 greater level of detail.
4461 * Improvements and bugfixes in hardware-assisted watchpoints
4463 It is now possible to watch array elements, struct members, and
4464 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4465 on x86 targets no longer erroneously trigger when the address is
4468 * Improvements in the native DJGPP version of GDB
4470 The distribution now includes all the scripts and auxiliary files
4471 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4472 machines ``out of the box''.
4474 The DJGPP version can now debug programs that use signals. It is
4475 possible to catch signals that happened in the debuggee, deliver
4476 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4477 would kill the program being debugged.) Programs that hook hardware
4478 interrupts (keyboard, timer, etc.) can also be debugged.
4480 It is now possible to debug DJGPP programs that redirect their
4481 standard handles or switch them to raw (as opposed to cooked) mode, or
4482 even close them. The command ``run < foo > bar'' works as expected,
4483 and ``info terminal'' reports useful information about the debuggee's
4484 terminal, including raw/cooked mode, redirection, etc.
4486 The DJGPP version now uses termios functions for console I/O, which
4487 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4490 DOS-style file names with drive letters are now fully supported by
4493 It is now possible to debug DJGPP programs that switch their working
4494 directory. It is also possible to rerun the debuggee any number of
4495 times without restarting GDB; thus, you can use the same setup,
4496 breakpoints, etc. for many debugging sessions.
4498 * New native configurations
4500 ARM GNU/Linux arm*-*-linux*
4501 PowerPC GNU/Linux powerpc-*-linux*
4505 Motorola MCore mcore-*-*
4506 x86 VxWorks i[3456]86-*-vxworks*
4507 PowerPC VxWorks powerpc-*-vxworks*
4508 TI TMS320C80 tic80-*-*
4510 * OBSOLETE configurations
4512 Altos 3068 m68*-altos-*
4513 Convex c1-*-*, c2-*-*
4515 ARM RISCix arm-*-* (as host)
4518 Configurations that have been declared obsolete will be commented out,
4519 but the code will be left in place. If there is no activity to revive
4520 these configurations before the next release of GDB, the sources will
4521 be permanently REMOVED.
4523 * Gould support removed
4525 Support for the Gould PowerNode and NP1 has been removed.
4527 * New features for SVR4
4529 On SVR4 native platforms (such as Solaris), if you attach to a process
4530 without first loading a symbol file, GDB will now attempt to locate and
4531 load symbols from the running process's executable file.
4533 * Many C++ enhancements
4535 C++ support has been greatly improved. Overload resolution now works properly
4536 in almost all cases. RTTI support is on the way.
4538 * Remote targets can connect to a sub-program
4540 A popen(3) style serial-device has been added. This device starts a
4541 sub-process (such as a stand-alone simulator) and then communicates
4542 with that. The sub-program to run is specified using the syntax
4543 ``|<program> <args>'' vis:
4545 (gdb) set remotedebug 1
4546 (gdb) target extended-remote |mn10300-elf-sim program-args
4548 * MIPS 64 remote protocol
4550 A long standing bug in the mips64 remote protocol where by GDB
4551 expected certain 32 bit registers (ex SR) to be transfered as 32
4552 instead of 64 bits has been fixed.
4554 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4555 added to provide backward compatibility with older versions of GDB.
4557 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4559 The command ``set remotebinarydownload'' command has been replaced by
4560 ``set remote X-packet''. Other commands in ``set remote'' family
4561 include ``set remote P-packet''.
4563 * Breakpoint commands accept ranges.
4565 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4566 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4567 ``tracepoint passcount'' also accepts a range of tracepoints.
4569 * ``apropos'' command added.
4571 The ``apropos'' command searches through command names and
4572 documentation strings, printing out matches, making it much easier to
4573 try to find a command that does what you are looking for.
4577 A new machine oriented interface (MI) has been added to GDB. This
4578 interface is designed for debug environments running GDB as a separate
4579 process. This is part of the long term libGDB project. See the
4580 "GDB/MI" chapter of the GDB manual for further information. It can be
4581 enabled by configuring with:
4583 .../configure --enable-gdbmi
4585 *** Changes in GDB-4.18:
4587 * New native configurations
4589 HP-UX 10.20 hppa*-*-hpux10.20
4590 HP-UX 11.x hppa*-*-hpux11.0*
4591 M68K GNU/Linux m68*-*-linux*
4595 Fujitsu FR30 fr30-*-elf*
4596 Intel StrongARM strongarm-*-*
4597 Mitsubishi D30V d30v-*-*
4599 * OBSOLETE configurations
4601 Gould PowerNode, NP1 np1-*-*, pn-*-*
4603 Configurations that have been declared obsolete will be commented out,
4604 but the code will be left in place. If there is no activity to revive
4605 these configurations before the next release of GDB, the sources will
4606 be permanently REMOVED.
4610 As a compatibility experiment, GDB's source files buildsym.h and
4611 buildsym.c have been converted to pure standard C, no longer
4612 containing any K&R compatibility code. We believe that all systems in
4613 use today either come with a standard C compiler, or have a GCC port
4614 available. If this is not true, please report the affected
4615 configuration to bug-gdb@gnu.org immediately. See the README file for
4616 information about getting a standard C compiler if you don't have one
4621 GDB now uses readline 2.2.
4623 * set extension-language
4625 You can now control the mapping between filename extensions and source
4626 languages by using the `set extension-language' command. For instance,
4627 you can ask GDB to treat .c files as C++ by saying
4628 set extension-language .c c++
4629 The command `info extensions' lists all of the recognized extensions
4630 and their associated languages.
4632 * Setting processor type for PowerPC and RS/6000
4634 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4635 you can use the `set processor' command to specify what variant of the
4636 PowerPC family you are debugging. The command
4640 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4641 following PowerPC and RS6000 variants:
4643 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4644 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4646 403GC IBM PowerPC 403GC
4647 505 Motorola PowerPC 505
4648 860 Motorola PowerPC 860 or 850
4649 601 Motorola PowerPC 601
4650 602 Motorola PowerPC 602
4651 603 Motorola/IBM PowerPC 603 or 603e
4652 604 Motorola PowerPC 604 or 604e
4653 750 Motorola/IBM PowerPC 750 or 750
4655 At the moment, this command just tells GDB what to name the
4656 special-purpose processor registers. Since almost all the affected
4657 registers are inaccessible to user-level programs, this command is
4658 only useful for remote debugging in its present form.
4662 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4663 more extensive support for HP-UX. Added features include shared
4664 library support, kernel threads and hardware watchpoints for 11.00,
4665 support for HP's ANSI C and C++ compilers, and a compatibility mode
4666 for xdb and dbx commands.
4670 HP's donation includes the new concept of catchpoints, which is a
4671 generalization of the old catch command. On HP-UX, it is now possible
4672 to catch exec, fork, and vfork, as well as library loading.
4674 This means that the existing catch command has changed; its first
4675 argument now specifies the type of catch to be set up. See the
4676 output of "help catch" for a list of catchpoint types.
4678 * Debugging across forks
4680 On HP-UX, you can choose which process to debug when a fork() happens
4685 HP has donated a curses-based terminal user interface (TUI). To get
4686 it, build with --enable-tui. Although this can be enabled for any
4687 configuration, at present it only works for native HP debugging.
4689 * GDB remote protocol additions
4691 A new protocol packet 'X' that writes binary data is now available.
4692 Default behavior is to try 'X', then drop back to 'M' if the stub
4693 fails to respond. The settable variable `remotebinarydownload'
4694 allows explicit control over the use of 'X'.
4696 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4697 full 64-bit address. The command
4699 set remoteaddresssize 32
4701 can be used to revert to the old behaviour. For existing remote stubs
4702 the change should not be noticed, as the additional address information
4705 In order to assist in debugging stubs, you may use the maintenance
4706 command `packet' to send any text string to the stub. For instance,
4708 maint packet heythere
4710 sends the packet "$heythere#<checksum>". Note that it is very easy to
4711 disrupt a debugging session by sending the wrong packet at the wrong
4714 The compare-sections command allows you to compare section data on the
4715 target to what is in the executable file without uploading or
4716 downloading, by comparing CRC checksums.
4718 * Tracing can collect general expressions
4720 You may now collect general expressions at tracepoints. This requires
4721 further additions to the target-side stub; see tracepoint.c and
4722 doc/agentexpr.texi for further details.
4724 * mask-address variable for Mips
4726 For Mips targets, you may control the zeroing of the upper 32 bits of
4727 a 64-bit address by entering `set mask-address on'. This is mainly
4728 of interest to users of embedded R4xxx and R5xxx processors.
4730 * Higher serial baud rates
4732 GDB's serial code now allows you to specify baud rates 57600, 115200,
4733 230400, and 460800 baud. (Note that your host system may not be able
4734 to achieve all of these rates.)
4738 The i960 configuration now includes an initial implementation of a
4739 builtin simulator, contributed by Jim Wilson.
4742 *** Changes in GDB-4.17:
4744 * New native configurations
4746 Alpha GNU/Linux alpha*-*-linux*
4747 Unixware 2.x i[3456]86-unixware2*
4748 Irix 6.x mips*-sgi-irix6*
4749 PowerPC GNU/Linux powerpc-*-linux*
4750 PowerPC Solaris powerpcle-*-solaris*
4751 Sparc GNU/Linux sparc-*-linux*
4752 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4756 Argonaut Risc Chip (ARC) arc-*-*
4757 Hitachi H8/300S h8300*-*-*
4758 Matsushita MN10200 w/simulator mn10200-*-*
4759 Matsushita MN10300 w/simulator mn10300-*-*
4760 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4761 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4762 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4763 Mitsubishi D10V w/simulator d10v-*-*
4764 Mitsubishi M32R/D w/simulator m32r-*-elf*
4765 Tsqware Sparclet sparclet-*-*
4766 NEC V850 w/simulator v850-*-*
4768 * New debugging protocols
4770 ARM with RDI protocol arm*-*-*
4771 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4772 DDB and LSI variants of PMON protocol mips*-*-*
4773 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4774 PowerPC with SDS protocol powerpc{,le}-*-eabi
4775 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4779 All configurations can now understand and use the DWARF 2 debugging
4780 format. The choice is automatic, if the symbol file contains DWARF 2
4785 GDB now includes basic Java language support. This support is
4786 only useful with Java compilers that produce native machine code.
4788 * solib-absolute-prefix and solib-search-path
4790 For SunOS and SVR4 shared libraries, you may now set the prefix for
4791 loading absolute shared library symbol files, and the search path for
4792 locating non-absolute shared library symbol files.
4794 * Live range splitting
4796 GDB can now effectively debug code for which GCC has performed live
4797 range splitting as part of its optimization. See gdb/doc/LRS for
4798 more details on the expected format of the stabs information.
4802 GDB's support for the GNU Hurd, including thread debugging, has been
4803 updated to work with current versions of the Hurd.
4807 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4808 instruction set. ARM GDB automatically detects when Thumb
4809 instructions are in use, and adjusts disassembly and backtracing
4814 GDB's MIPS target configurations now handle the MIP16 16-bit
4819 GDB now includes support for overlays; if an executable has been
4820 linked such that multiple sections are based at the same address, GDB
4821 will decide which section to use for symbolic info. You can choose to
4822 control the decision manually, using overlay commands, or implement
4823 additional target-side support and use "overlay load-target" to bring
4824 in the overlay mapping. Do "help overlay" for more detail.
4828 The command "info symbol <address>" displays information about
4829 the symbol at the specified address.
4833 The standard remote protocol now includes an extension that allows
4834 asynchronous collection and display of trace data. This requires
4835 extensive support in the target-side debugging stub. Tracing mode
4836 includes a new interaction mode in GDB and new commands: see the
4837 file tracepoint.c for more details.
4841 Configurations for embedded MIPS now include a simulator contributed
4842 by Cygnus Solutions. The simulator supports the instruction sets
4843 of most MIPS variants.
4847 Sparc configurations may now include the ERC32 simulator contributed
4848 by the European Space Agency. The simulator is not built into
4849 Sparc targets by default; configure with --enable-sim to include it.
4853 For target configurations that may include multiple variants of a
4854 basic architecture (such as MIPS and SH), you may now set the
4855 architecture explicitly. "set arch" sets, "info arch" lists
4856 the possible architectures.
4858 *** Changes in GDB-4.16:
4860 * New native configurations
4862 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4863 M68K NetBSD m68k-*-netbsd*
4864 PowerPC AIX 4.x powerpc-*-aix*
4865 PowerPC MacOS powerpc-*-macos*
4866 PowerPC Windows NT powerpcle-*-cygwin32
4867 RS/6000 AIX 4.x rs6000-*-aix4*
4871 ARM with RDP protocol arm-*-*
4872 I960 with MON960 i960-*-coff
4873 MIPS VxWorks mips*-*-vxworks*
4874 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4875 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4877 Matra Sparclet sparclet-*-*
4881 The powerpc-eabi configuration now includes the PSIM simulator,
4882 contributed by Andrew Cagney, with assistance from Mike Meissner.
4883 PSIM is a very elaborate model of the PowerPC, including not only
4884 basic instruction set execution, but also details of execution unit
4885 performance and I/O hardware. See sim/ppc/README for more details.
4889 GDB now works with Solaris 2.5.
4891 * Windows 95/NT native
4893 GDB will now work as a native debugger on Windows 95 and Windows NT.
4894 To build it from source, you must use the "gnu-win32" environment,
4895 which uses a DLL to emulate enough of Unix to run the GNU tools.
4896 Further information, binaries, and sources are available at
4897 ftp.cygnus.com, under pub/gnu-win32.
4899 * dont-repeat command
4901 If a user-defined command includes the command `dont-repeat', then the
4902 command will not be repeated if the user just types return. This is
4903 useful if the command is time-consuming to run, so that accidental
4904 extra keystrokes don't run the same command many times.
4906 * Send break instead of ^C
4908 The standard remote protocol now includes an option to send a break
4909 rather than a ^C to the target in order to interrupt it. By default,
4910 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4912 * Remote protocol timeout
4914 The standard remote protocol includes a new variable `remotetimeout'
4915 that allows you to set the number of seconds before GDB gives up trying
4916 to read from the target. The default value is 2.
4918 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4920 By default GDB will automatically keep track of objects as they are
4921 loaded and unloaded by the dynamic linker. By using the command `set
4922 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4923 when shared library events occur, thus allowing you to set breakpoints
4924 in shared libraries which are explicitly loaded by the inferior.
4926 Note this feature does not work on hpux8. On hpux9 you must link
4927 /usr/lib/end.o into your program. This feature should work
4928 automatically on hpux10.
4930 * Irix 5.x hardware watchpoint support
4932 Irix 5 configurations now support the use of hardware watchpoints.
4934 * Mips protocol "SYN garbage limit"
4936 When debugging a Mips target using the `target mips' protocol, you
4937 may set the number of characters that GDB will ignore by setting
4938 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4939 every character. The default value is 1050.
4941 * Recording and replaying remote debug sessions
4943 If you set `remotelogfile' to the name of a file, gdb will write to it
4944 a recording of a remote debug session. This recording may then be
4945 replayed back to gdb using "gdbreplay". See gdbserver/README for
4946 details. This is useful when you have a problem with GDB while doing
4947 remote debugging; you can make a recording of the session and send it
4948 to someone else, who can then recreate the problem.
4950 * Speedups for remote debugging
4952 GDB includes speedups for downloading and stepping MIPS systems using
4953 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4954 and more efficient S-record downloading.
4956 * Memory use reductions and statistics collection
4958 GDB now uses less memory and reports statistics about memory usage.
4959 Try the `maint print statistics' command, for example.
4961 *** Changes in GDB-4.15:
4963 * Psymtabs for XCOFF
4965 The symbol reader for AIX GDB now uses partial symbol tables. This
4966 can greatly improve startup time, especially for large executables.
4968 * Remote targets use caching
4970 Remote targets now use a data cache to speed up communication with the
4971 remote side. The data cache could lead to incorrect results because
4972 it doesn't know about volatile variables, thus making it impossible to
4973 debug targets which use memory mapped I/O devices. `set remotecache
4974 off' turns the the data cache off.
4976 * Remote targets may have threads
4978 The standard remote protocol now includes support for multiple threads
4979 in the target system, using new protocol commands 'H' and 'T'. See
4980 gdb/remote.c for details.
4984 If GDB is configured with `--enable-netrom', then it will include
4985 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4986 acts as though it is a bank of ROM on the target board, but you can
4987 write into it over the network. GDB's support consists only of
4988 support for fast loading into the emulated ROM; to debug, you must use
4989 another protocol, such as standard remote protocol. The usual
4990 sequence is something like
4992 target nrom <netrom-hostname>
4994 target remote <netrom-hostname>:1235
4998 GDB now includes support for the Apple Macintosh, as a host only. It
4999 may be run as either an MPW tool or as a standalone application, and
5000 it can debug through the serial port. All the usual GDB commands are
5001 available, but to the target command, you must supply "serial" as the
5002 device type instead of "/dev/ttyXX". See mpw-README in the main
5003 directory for more information on how to build. The MPW configuration
5004 scripts */mpw-config.in support only a few targets, and only the
5005 mips-idt-ecoff target has been tested.
5009 GDB configuration now uses autoconf. This is not user-visible,
5010 but does simplify configuration and building.
5014 GDB now supports hpux10.
5016 *** Changes in GDB-4.14:
5018 * New native configurations
5020 x86 FreeBSD i[345]86-*-freebsd
5021 x86 NetBSD i[345]86-*-netbsd
5022 NS32k NetBSD ns32k-*-netbsd
5023 Sparc NetBSD sparc-*-netbsd
5027 A29K VxWorks a29k-*-vxworks
5028 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5029 CPU32 EST-300 emulator m68*-*-est*
5030 PowerPC ELF powerpc-*-elf
5033 * Alpha OSF/1 support for procfs
5035 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5036 possible to attach to running processes. As the mounting of the /proc
5037 filesystem is optional on the Alpha, GDB automatically determines
5038 the availability of /proc during startup. This can lead to problems
5039 if /proc is unmounted after GDB has been started.
5041 * Arguments to user-defined commands
5043 User commands may accept up to 10 arguments separated by whitespace.
5044 Arguments are accessed within the user command via $arg0..$arg9. A
5047 print $arg0 + $arg1 + $arg2
5049 To execute the command use:
5052 Defines the command "adder" which prints the sum of its three arguments.
5053 Note the arguments are text substitutions, so they may reference variables,
5054 use complex expressions, or even perform inferior function calls.
5056 * New `if' and `while' commands
5058 This makes it possible to write more sophisticated user-defined
5059 commands. Both commands take a single argument, which is the
5060 expression to evaluate, and must be followed by the commands to
5061 execute, one per line, if the expression is nonzero, the list being
5062 terminated by the word `end'. The `if' command list may include an
5063 `else' word, which causes the following commands to be executed only
5064 if the expression is zero.
5066 * Fortran source language mode
5068 GDB now includes partial support for Fortran 77. It will recognize
5069 Fortran programs and can evaluate a subset of Fortran expressions, but
5070 variables and functions may not be handled correctly. GDB will work
5071 with G77, but does not yet know much about symbols emitted by other
5074 * Better HPUX support
5076 Most debugging facilities now work on dynamic executables for HPPAs
5077 running hpux9 or later. You can attach to running dynamically linked
5078 processes, but by default the dynamic libraries will be read-only, so
5079 for instance you won't be able to put breakpoints in them. To change
5080 that behavior do the following before running the program:
5086 This will cause the libraries to be mapped private and read-write.
5087 To revert to the normal behavior, do this:
5093 You cannot set breakpoints or examine data in the library until after
5094 the library is loaded if the function/data symbols do not have
5097 GDB can now also read debug symbols produced by the HP C compiler on
5098 HPPAs (sorry, no C++, Fortran or 68k support).
5100 * Target byte order now dynamically selectable
5102 You can choose which byte order to use with a target system, via the
5103 commands "set endian big" and "set endian little", and you can see the
5104 current setting by using "show endian". You can also give the command
5105 "set endian auto", in which case GDB will use the byte order
5106 associated with the executable. Currently, only embedded MIPS
5107 configurations support dynamic selection of target byte order.
5109 * New DOS host serial code
5111 This version uses DPMI interrupts to handle buffered I/O, so you
5112 no longer need to run asynctsr when debugging boards connected to
5115 *** Changes in GDB-4.13:
5117 * New "complete" command
5119 This lists all the possible completions for the rest of the line, if it
5120 were to be given as a command itself. This is intended for use by emacs.
5122 * Trailing space optional in prompt
5124 "set prompt" no longer adds a space for you after the prompt you set. This
5125 allows you to set a prompt which ends in a space or one that does not.
5127 * Breakpoint hit counts
5129 "info break" now displays a count of the number of times the breakpoint
5130 has been hit. This is especially useful in conjunction with "ignore"; you
5131 can ignore a large number of breakpoint hits, look at the breakpoint info
5132 to see how many times the breakpoint was hit, then run again, ignoring one
5133 less than that number, and this will get you quickly to the last hit of
5136 * Ability to stop printing at NULL character
5138 "set print null-stop" will cause GDB to stop printing the characters of
5139 an array when the first NULL is encountered. This is useful when large
5140 arrays actually contain only short strings.
5142 * Shared library breakpoints
5144 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5145 breakpoints in shared libraries before the executable is run.
5147 * Hardware watchpoints
5149 There is a new hardware breakpoint for the watch command for sparclite
5150 targets. See gdb/sparclite/hw_breakpoint.note.
5152 Hardware watchpoints are also now supported under GNU/Linux.
5156 Annotations have been added. These are for use with graphical interfaces,
5157 and are still experimental. Currently only gdba.el uses these.
5159 * Improved Irix 5 support
5161 GDB now works properly with Irix 5.2.
5163 * Improved HPPA support
5165 GDB now works properly with the latest GCC and GAS.
5167 * New native configurations
5169 Sequent PTX4 i[34]86-sequent-ptx4
5170 HPPA running OSF/1 hppa*-*-osf*
5171 Atari TT running SVR4 m68*-*-sysv4*
5172 RS/6000 LynxOS rs6000-*-lynxos*
5176 OS/9000 i[34]86-*-os9k
5177 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5180 * Hitachi SH7000 and E7000-PC ICE support
5182 There is now support for communicating with the Hitachi E7000-PC ICE.
5183 This is available automatically when GDB is configured for the SH.
5187 As usual, a variety of small fixes and improvements, both generic
5188 and configuration-specific. See the ChangeLog for more detail.
5190 *** Changes in GDB-4.12:
5192 * Irix 5 is now supported
5196 GDB-4.12 on the HPPA has a number of changes which make it unable
5197 to debug the output from the currently released versions of GCC and
5198 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5199 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5200 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5203 *** Changes in GDB-4.11:
5205 * User visible changes:
5209 The "set remotedebug" option is now consistent between the mips remote
5210 target, remote targets using the gdb-specific protocol, UDI (AMD's
5211 debug protocol for the 29k) and the 88k bug monitor. It is now an
5212 integer specifying a debug level (normally 0 or 1, but 2 means more
5213 debugging info for the mips target).
5215 * DEC Alpha native support
5217 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5218 debug info, but GDB works fairly well with the DEC compiler and should
5219 work with a future GCC release. See the README file for a few
5220 Alpha-specific notes.
5222 * Preliminary thread implementation
5224 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5226 * LynxOS native and target support for 386
5228 This release has been hosted on LynxOS 2.2, and also can be configured
5229 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5232 * Improvements in C++ mangling/demangling.
5234 This release has much better g++ debugging, specifically in name
5235 mangling/demangling, virtual function calls, print virtual table,
5236 call methods, ...etc.
5238 *** Changes in GDB-4.10:
5240 * User visible changes:
5242 Remote debugging using the GDB-specific (`target remote') protocol now
5243 supports the `load' command. This is only useful if you have some
5244 other way of getting the stub to the target system, and you can put it
5245 somewhere in memory where it won't get clobbered by the download.
5247 Filename completion now works.
5249 When run under emacs mode, the "info line" command now causes the
5250 arrow to point to the line specified. Also, "info line" prints
5251 addresses in symbolic form (as well as hex).
5253 All vxworks based targets now support a user settable option, called
5254 vxworks-timeout. This option represents the number of seconds gdb
5255 should wait for responses to rpc's. You might want to use this if
5256 your vxworks target is, perhaps, a slow software simulator or happens
5257 to be on the far side of a thin network line.
5261 This release contains support for using a DEC alpha as a GDB host for
5262 cross debugging. Native alpha debugging is not supported yet.
5265 *** Changes in GDB-4.9:
5269 This is the first GDB release which is accompanied by a matching testsuite.
5270 The testsuite requires installation of dejagnu, which should be available
5271 via ftp from most sites that carry GNU software.
5275 'Cfront' style demangling has had its name changed to 'ARM' style, to
5276 emphasize that it was written from the specifications in the C++ Annotated
5277 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5278 disclaimers, it still generated too much confusion with users attempting to
5279 use gdb with AT&T cfront.
5283 GDB now uses a standard remote interface to a simulator library.
5284 So far, the library contains simulators for the Zilog Z8001/2, the
5285 Hitachi H8/300, H8/500 and Super-H.
5287 * New targets supported
5289 H8/300 simulator h8300-hitachi-hms or h8300hms
5290 H8/500 simulator h8500-hitachi-hms or h8500hms
5291 SH simulator sh-hitachi-hms or sh
5292 Z8000 simulator z8k-zilog-none or z8ksim
5293 IDT MIPS board over serial line mips-idt-ecoff
5295 Cross-debugging to GO32 targets is supported. It requires a custom
5296 version of the i386-stub.c module which is integrated with the
5297 GO32 memory extender.
5299 * New remote protocols
5301 MIPS remote debugging protocol.
5303 * New source languages supported
5305 This version includes preliminary support for Chill, a Pascal like language
5306 used by telecommunications companies. Chill support is also being integrated
5307 into the GNU compiler, but we don't know when it will be publically available.
5310 *** Changes in GDB-4.8:
5312 * HP Precision Architecture supported
5314 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5315 version of this support was available as a set of patches from the
5316 University of Utah. GDB does not support debugging of programs
5317 compiled with the HP compiler, because HP will not document their file
5318 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5319 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5321 Many problems in the preliminary version have been fixed.
5323 * Faster and better demangling
5325 We have improved template demangling and fixed numerous bugs in the GNU style
5326 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5327 character types (wchar_t) are now supported. Demangling of each symbol is now
5328 only done once, and is cached when the symbol table for a file is read in.
5329 This results in a small increase in memory usage for C programs, a moderate
5330 increase in memory usage for C++ programs, and a fantastic speedup in
5333 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5334 from the specifications in the Annotated Reference Manual, which AT&T's
5335 compiler does not actually implement.
5337 * G++ multiple inheritance compiler problem
5339 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5340 inheritance lattices was reworked to properly discover ambiguities. We
5341 recently found an example which causes this new algorithm to fail in a
5342 very subtle way, producing bad debug information for those classes.
5343 The file 'gcc.patch' (in this directory) can be applied to gcc to
5344 circumvent the problem. A future GCC release will contain a complete
5347 The previous G++ debug info problem (mentioned below for the gdb-4.7
5348 release) is fixed in gcc version 2.3.2.
5350 * Improved configure script
5352 The `configure' script will now attempt to guess your system type if
5353 you don't supply a host system type. The old scheme of supplying a
5354 host system triplet is preferable over using this. All the magic is
5355 done in the new `config.guess' script. Examine it for details.
5357 We have also brought our configure script much more in line with the FSF's
5358 version. It now supports the --with-xxx options. In particular,
5359 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5360 The resulting GDB will not be able to read arbitrary object file formats --
5361 only the format ``expected'' to be used on the configured target system.
5362 We hope to make this the default in a future release.
5364 * Documentation improvements
5366 There's new internal documentation on how to modify GDB, and how to
5367 produce clean changes to the code. We implore people to read it
5368 before submitting changes.
5370 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5371 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5372 `info' files are also provided. To build `info' files from scratch,
5373 you will need the latest `makeinfo' release, which will be available in
5374 a future texinfo-X.Y release.
5376 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5377 We're not sure exactly which versions have this problem, but it has
5378 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5379 or better. If that isn't possible, there is a patch in
5380 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5381 around this problem.
5385 GDB now supports array constants that can be used in expressions typed in by
5386 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5387 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5390 The new directory `gdb/sparclite' contains a program that demonstrates
5391 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5393 * New native hosts supported
5395 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5396 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5398 * New targets supported
5400 AMD 29k family via UDI a29k-amd-udi or udi29k
5402 * New file formats supported
5404 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5405 HPUX core files, and SCO 3.2v2 core files.
5409 Attaching to processes now works again; thanks for the many bug reports.
5411 We have also stomped on a bunch of core dumps caused by
5412 printf_filtered("%s") problems.
5414 We eliminated a copyright problem on the rpc and ptrace header files
5415 for VxWorks, which was discovered at the last minute during the 4.7
5416 release. You should now be able to build a VxWorks GDB.
5418 You can now interrupt gdb while an attached process is running. This
5419 will cause the attached process to stop, and give control back to GDB.
5421 We fixed problems caused by using too many file descriptors
5422 for reading symbols from object files and libraries. This was
5423 especially a problem for programs that used many (~100) shared
5426 The `step' command now only enters a subroutine if there is line number
5427 information for the subroutine. Otherwise it acts like the `next'
5428 command. Previously, `step' would enter subroutines if there was
5429 any debugging information about the routine. This avoids problems
5430 when using `cc -g1' on MIPS machines.
5432 * Internal improvements
5434 GDB's internal interfaces have been improved to make it easier to support
5435 debugging of multiple languages in the future.
5437 GDB now uses a common structure for symbol information internally.
5438 Minimal symbols (derived from linkage symbols in object files), partial
5439 symbols (from a quick scan of debug information), and full symbols
5440 contain a common subset of information, making it easier to write
5441 shared code that handles any of them.
5443 * New command line options
5445 We now accept --silent as an alias for --quiet.
5449 The memory-mapped-malloc library is now licensed under the GNU Library
5450 General Public License.
5452 *** Changes in GDB-4.7:
5454 * Host/native/target split
5456 GDB has had some major internal surgery to untangle the support for
5457 hosts and remote targets. Now, when you configure GDB for a remote
5458 target, it will no longer load in all of the support for debugging
5459 local programs on the host. When fully completed and tested, this will
5460 ensure that arbitrary host/target combinations are possible.
5462 The primary conceptual shift is to separate the non-portable code in
5463 GDB into three categories. Host specific code is required any time GDB
5464 is compiled on that host, regardless of the target. Target specific
5465 code relates to the peculiarities of the target, but can be compiled on
5466 any host. Native specific code is everything else: it can only be
5467 built when the host and target are the same system. Child process
5468 handling and core file support are two common `native' examples.
5470 GDB's use of /proc for controlling Unix child processes is now cleaner.
5471 It has been split out into a single module under the `target_ops' vector,
5472 plus two native-dependent functions for each system that uses /proc.
5474 * New hosts supported
5476 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5477 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5478 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5480 * New targets supported
5482 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5483 68030 and CPU32 m68030-*-*, m68332-*-*
5485 * New native hosts supported
5487 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5488 (386bsd is not well tested yet)
5489 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5491 * New file formats supported
5493 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5494 supports reading of `a.out.adobe' object files, which are an a.out
5495 format extended with minimal information about multiple sections.
5499 `show copying' is the same as the old `info copying'.
5500 `show warranty' is the same as `info warrantee'.
5501 These were renamed for consistency. The old commands continue to work.
5503 `info handle' is a new alias for `info signals'.
5505 You can now define pre-command hooks, which attach arbitrary command
5506 scripts to any command. The commands in the hook will be executed
5507 prior to the user's command. You can also create a hook which will be
5508 executed whenever the program stops. See gdb.texinfo.
5512 We now deal with Cfront style name mangling, and can even extract type
5513 info from mangled symbols. GDB can automatically figure out which
5514 symbol mangling style your C++ compiler uses.
5516 Calling of methods and virtual functions has been improved as well.
5520 The crash that occured when debugging Sun Ansi-C compiled binaries is
5521 fixed. This was due to mishandling of the extra N_SO stabs output
5524 We also finally got Ultrix 4.2 running in house, and fixed core file
5525 support, with help from a dozen people on the net.
5527 John M. Farrell discovered that the reason that single-stepping was so
5528 slow on all of the Mips based platforms (primarily SGI and DEC) was
5529 that we were trying to demangle and lookup a symbol used for internal
5530 purposes on every instruction that was being stepped through. Changing
5531 the name of that symbol so that it couldn't be mistaken for a C++
5532 mangled symbol sped things up a great deal.
5534 Rich Pixley sped up symbol lookups in general by getting much smarter
5535 about when C++ symbol mangling is necessary. This should make symbol
5536 completion (TAB on the command line) much faster. It's not as fast as
5537 we'd like, but it's significantly faster than gdb-4.6.
5541 A new user controllable variable 'call_scratch_address' can
5542 specify the location of a scratch area to be used when GDB
5543 calls a function in the target. This is necessary because the
5544 usual method of putting the scratch area on the stack does not work
5545 in systems that have separate instruction and data spaces.
5547 We integrated changes to support the 29k UDI (Universal Debugger
5548 Interface), but discovered at the last minute that we didn't have all
5549 of the appropriate copyright paperwork. We are working with AMD to
5550 resolve this, and hope to have it available soon.
5554 We have sped up the remote serial line protocol, especially for targets
5555 with lots of registers. It now supports a new `expedited status' ('T')
5556 message which can be used in place of the existing 'S' status message.
5557 This allows the remote stub to send only the registers that GDB
5558 needs to make a quick decision about single-stepping or conditional
5559 breakpoints, eliminating the need to fetch the entire register set for
5560 each instruction being stepped through.
5562 The GDB remote serial protocol now implements a write-through cache for
5563 registers, only re-reading the registers if the target has run.
5565 There is also a new remote serial stub for SPARC processors. You can
5566 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5567 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5568 processor with a serial port.
5572 Configure.in files have become much easier to read and modify. A new
5573 `table driven' format makes it more obvious what configurations are
5574 supported, and what files each one uses.
5578 There is a new opcodes library which will eventually contain all of the
5579 disassembly routines and opcode tables. At present, it only contains
5580 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5581 disassembler (binutils/objdump) to share these routines.
5583 The libiberty library is now copylefted under the GNU Library General
5584 Public License. This allows more liberal use, and was done so libg++
5585 can use it. This makes no difference to GDB, since the Library License
5586 grants all the rights from the General Public License.
5590 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5591 reference to the stabs symbol info used by the debugger. It is (as far
5592 as we know) the only published document on this fascinating topic. We
5593 encourage you to read it, compare it to the stabs information on your
5594 system, and send improvements on the document in general (to
5595 bug-gdb@prep.ai.mit.edu).
5597 And, of course, many bugs have been fixed.
5600 *** Changes in GDB-4.6:
5602 * Better support for C++ function names
5604 GDB now accepts as input the "demangled form" of C++ overloaded function
5605 names and member function names, and can do command completion on such names
5606 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5607 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5608 Make use of command completion, it is your friend.
5610 GDB also now accepts a variety of C++ mangled symbol formats. They are
5611 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5612 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5613 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5614 for the list of formats.
5616 * G++ symbol mangling problem
5618 Recent versions of gcc have a bug in how they emit debugging information for
5619 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5620 directory) can be applied to gcc to fix the problem. Alternatively, if you
5621 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5622 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5623 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5626 * New 'maintenance' command
5628 All of the commands related to hacking GDB internals have been moved out of
5629 the main command set, and now live behind the 'maintenance' command. This
5630 can also be abbreviated as 'mt'. The following changes were made:
5632 dump-me -> maintenance dump-me
5633 info all-breakpoints -> maintenance info breakpoints
5634 printmsyms -> maintenance print msyms
5635 printobjfiles -> maintenance print objfiles
5636 printpsyms -> maintenance print psymbols
5637 printsyms -> maintenance print symbols
5639 The following commands are new:
5641 maintenance demangle Call internal GDB demangler routine to
5642 demangle a C++ link name and prints the result.
5643 maintenance print type Print a type chain for a given symbol
5645 * Change to .gdbinit file processing
5647 We now read the $HOME/.gdbinit file before processing the argv arguments
5648 (e.g. reading symbol files or core files). This allows global parameters to
5649 be set, which will apply during the symbol reading. The ./.gdbinit is still
5650 read after argv processing.
5652 * New hosts supported
5654 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5656 GNU/Linux support i386-unknown-linux or linux
5658 We are also including code to support the HP/PA running BSD and HPUX. This
5659 is almost guaranteed not to work, as we didn't have time to test or build it
5660 for this release. We are including it so that the more adventurous (or
5661 masochistic) of you can play with it. We also had major problems with the
5662 fact that the compiler that we got from HP doesn't support the -g option.
5665 * New targets supported
5667 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5669 * More smarts about finding #include files
5671 GDB now remembers the compilation directory for all include files, and for
5672 all files from which C is generated (like yacc and lex sources). This
5673 greatly improves GDB's ability to find yacc/lex sources, and include files,
5674 especially if you are debugging your program from a directory different from
5675 the one that contains your sources.
5677 We also fixed a bug which caused difficulty with listing and setting
5678 breakpoints in include files which contain C code. (In the past, you had to
5679 try twice in order to list an include file that you hadn't looked at before.)
5681 * Interesting infernals change
5683 GDB now deals with arbitrary numbers of sections, where the symbols for each
5684 section must be relocated relative to that section's landing place in the
5685 target's address space. This work was needed to support ELF with embedded
5686 stabs used by Solaris-2.0.
5688 * Bug fixes (of course!)
5690 There have been loads of fixes for the following things:
5691 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5692 i960, stabs, DOS(GO32), procfs, etc...
5694 See the ChangeLog for details.
5696 *** Changes in GDB-4.5:
5698 * New machines supported (host and target)
5700 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5702 SGI Irix-4.x mips-sgi-irix4 or iris4
5704 * New malloc package
5706 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5707 Mmalloc is capable of handling mutiple heaps of memory. It is also
5708 capable of saving a heap to a file, and then mapping it back in later.
5709 This can be used to greatly speedup the startup of GDB by using a
5710 pre-parsed symbol table which lives in a mmalloc managed heap. For
5711 more details, please read mmalloc/mmalloc.texi.
5715 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5716 'help info proc' for details.
5718 * MIPS ecoff symbol table format
5720 The code that reads MIPS symbol table format is now supported on all hosts.
5721 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5724 * File name changes for MS-DOS
5726 Many files in the config directories have been renamed to make it easier to
5727 support GDB on MS-DOSe systems (which have very restrictive file name
5728 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5729 environment) is close to working but has some remaining problems. Note
5730 that debugging of DOS programs is not supported, due to limitations
5731 in the ``operating system'', but it can be used to host cross-debugging.
5733 * Cross byte order fixes
5735 Many fixes have been made to support cross debugging of Sparc and MIPS
5736 targets from hosts whose byte order differs.
5738 * New -mapped and -readnow options
5740 If memory-mapped files are available on your system through the 'mmap'
5741 system call, you can use the -mapped option on the `file' or
5742 `symbol-file' commands to cause GDB to write the symbols from your
5743 program into a reusable file. If the program you are debugging is
5744 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5745 Future GDB debugging sessions will notice the presence of this file,
5746 and will quickly map in symbol information from it, rather than reading
5747 the symbol table from the executable program. Using the '-mapped'
5748 option in a GDB `file' or `symbol-file' command has the same effect as
5749 starting GDB with the '-mapped' command-line option.
5751 You can cause GDB to read the entire symbol table immediately by using
5752 the '-readnow' option with any of the commands that load symbol table
5753 information (or on the GDB command line). This makes the command
5754 slower, but makes future operations faster.
5756 The -mapped and -readnow options are typically combined in order to
5757 build a `fred.syms' file that contains complete symbol information.
5758 A simple GDB invocation to do nothing but build a `.syms' file for future
5761 gdb -batch -nx -mapped -readnow programname
5763 The `.syms' file is specific to the host machine on which GDB is run.
5764 It holds an exact image of GDB's internal symbol table. It cannot be
5765 shared across multiple host platforms.
5767 * longjmp() handling
5769 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5770 siglongjmp() without losing control. This feature has not yet been ported to
5771 all systems. It currently works on many 386 platforms, all MIPS-based
5772 platforms (SGI, DECstation, etc), and Sun3/4.
5776 Preliminary work has been put in to support the new Solaris OS from Sun. At
5777 this time, it can control and debug processes, but it is not capable of
5782 As always, many many bug fixes. The major areas were with g++, and mipsread.
5783 People using the MIPS-based platforms should experience fewer mysterious
5784 crashes and trashed symbol tables.
5786 *** Changes in GDB-4.4:
5788 * New machines supported (host and target)
5790 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5792 BSD Reno on Vax vax-dec-bsd
5793 Ultrix on Vax vax-dec-ultrix
5795 * New machines supported (target)
5797 AMD 29000 embedded, using EBMON a29k-none-none
5801 GDB continues to improve its handling of C++. `References' work better.
5802 The demangler has also been improved, and now deals with symbols mangled as
5803 per the Annotated C++ Reference Guide.
5805 GDB also now handles `stabs' symbol information embedded in MIPS
5806 `ecoff' symbol tables. Since the ecoff format was not easily
5807 extensible to handle new languages such as C++, this appeared to be a
5808 good way to put C++ debugging info into MIPS binaries. This option
5809 will be supported in the GNU C compiler, version 2, when it is
5812 * New features for SVR4
5814 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5815 shared libraries. Debugging dynamically linked programs should present
5816 only minor differences from debugging statically linked programs.
5818 The `info proc' command will print out information about any process
5819 on an SVR4 system (including the one you are debugging). At the moment,
5820 it prints the address mappings of the process.
5822 If you bring up GDB on another SVR4 system, please send mail to
5823 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5825 * Better dynamic linking support in SunOS
5827 Reading symbols from shared libraries which contain debugging symbols
5828 now works properly. However, there remain issues such as automatic
5829 skipping of `transfer vector' code during function calls, which
5830 make it harder to debug code in a shared library, than to debug the
5831 same code linked statically.
5835 GDB is now using the latest `getopt' routines from the FSF. This
5836 version accepts the -- prefix for options with long names. GDB will
5837 continue to accept the old forms (-option and +option) as well.
5838 Various single letter abbreviations for options have been explicity
5839 added to the option table so that they won't get overshadowed in the
5840 future by other options that begin with the same letter.
5844 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5845 Many assorted bugs have been handled. Many more remain to be handled.
5846 See the various ChangeLog files (primarily in gdb and bfd) for details.
5849 *** Changes in GDB-4.3:
5851 * New machines supported (host and target)
5853 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5854 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5855 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5857 * Almost SCO Unix support
5859 We had hoped to support:
5860 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5861 (except for core file support), but we discovered very late in the release
5862 that it has problems with process groups that render gdb unusable. Sorry
5863 about that. I encourage people to fix it and post the fixes.
5865 * Preliminary ELF and DWARF support
5867 GDB can read ELF object files on System V Release 4, and can handle
5868 debugging records for C, in DWARF format, in ELF files. This support
5869 is preliminary. If you bring up GDB on another SVR4 system, please
5870 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5875 GDB now uses the latest `readline' library. One user-visible change
5876 is that two tabs will list possible command completions, which previously
5877 required typing M-? (meta-question mark, or ESC ?).
5881 The `stepi' bug that many of you noticed has been squashed.
5882 Many bugs in C++ have been handled. Many more remain to be handled.
5883 See the various ChangeLog files (primarily in gdb and bfd) for details.
5885 * State of the MIPS world (in case you wondered):
5887 GDB can understand the symbol tables emitted by the compilers
5888 supplied by most vendors of MIPS-based machines, including DEC. These
5889 symbol tables are in a format that essentially nobody else uses.
5891 Some versions of gcc come with an assembler post-processor called
5892 mips-tfile. This program is required if you want to do source-level
5893 debugging of gcc-compiled programs. I believe FSF does not ship
5894 mips-tfile with gcc version 1, but it will eventually come with gcc
5897 Debugging of g++ output remains a problem. g++ version 1.xx does not
5898 really support it at all. (If you're lucky, you should be able to get
5899 line numbers and stack traces to work, but no parameters or local
5900 variables.) With some work it should be possible to improve the
5903 When gcc version 2 is released, you will have somewhat better luck.
5904 However, even then you will get confusing results for inheritance and
5907 We will eventually provide full debugging of g++ output on
5908 DECstations. This will probably involve some kind of stabs-in-ecoff
5909 encapulation, but the details have not been worked out yet.
5912 *** Changes in GDB-4.2:
5914 * Improved configuration
5916 Only one copy of `configure' exists now, and it is not self-modifying.
5917 Porting BFD is simpler.
5921 The `step' and `next' commands now only stop at the first instruction
5922 of a source line. This prevents the multiple stops that used to occur
5923 in switch statements, for-loops, etc. `Step' continues to stop if a
5924 function that has debugging information is called within the line.
5928 Lots of small bugs fixed. More remain.
5930 * New host supported (not target)
5932 Intel 386 PC clone running Mach i386-none-mach
5935 *** Changes in GDB-4.1:
5937 * Multiple source language support
5939 GDB now has internal scaffolding to handle several source languages.
5940 It determines the type of each source file from its filename extension,
5941 and will switch expression parsing and number formatting to match the
5942 language of the function in the currently selected stack frame.
5943 You can also specifically set the language to be used, with
5944 `set language c' or `set language modula-2'.
5948 GDB now has preliminary support for the GNU Modula-2 compiler,
5949 currently under development at the State University of New York at
5950 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5951 continue through the fall of 1991 and into 1992.
5953 Other Modula-2 compilers are currently not supported, and attempting to
5954 debug programs compiled with them will likely result in an error as the
5955 symbol table is read. Feel free to work on it, though!
5957 There are hooks in GDB for strict type checking and range checking,
5958 in the `Modula-2 philosophy', but they do not currently work.
5962 GDB can now write to executable and core files (e.g. patch
5963 a variable's value). You must turn this switch on, specify
5964 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5965 by assigning a new value to a variable. Modifications take
5968 * Automatic SunOS shared library reading
5970 When you run your program, GDB automatically determines where its
5971 shared libraries (if any) have been loaded, and reads their symbols.
5972 The `share' command is no longer needed. This also works when
5973 examining core files.
5977 You can specify the number of lines that the `list' command shows.
5980 * New machines supported (host and target)
5982 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5983 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5984 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5986 * New hosts supported (not targets)
5988 IBM RT/PC: romp-ibm-aix or rtpc
5990 * New targets supported (not hosts)
5992 AMD 29000 embedded with COFF a29k-none-coff
5993 AMD 29000 embedded with a.out a29k-none-aout
5994 Ultracomputer remote kernel debug a29k-nyu-kern
5996 * New remote interfaces
6002 *** Changes in GDB-4.0:
6006 Wide output is wrapped at good places to make the output more readable.
6008 Gdb now supports cross-debugging from a host machine of one type to a
6009 target machine of another type. Communication with the target system
6010 is over serial lines. The ``target'' command handles connecting to the
6011 remote system; the ``load'' command will download a program into the
6012 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6013 also supports debugging of realtime processes running under VxWorks,
6014 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6015 stub on the target system.
6017 New CPUs supported include the AMD 29000 and Intel 960.
6019 GDB now reads object files and symbol tables via a ``binary file''
6020 library, which allows a single copy of GDB to debug programs of multiple
6021 object file types such as a.out and coff.
6023 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6024 refcard.dvi and refcard.ps are available to format it).
6027 * Control-Variable user interface simplified
6029 All variables that control the operation of the debugger can be set
6030 by the ``set'' command, and displayed by the ``show'' command.
6032 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6033 ``Show prompt'' produces the response:
6034 Gdb's prompt is new-gdb=>.
6036 What follows are the NEW set commands. The command ``help set'' will
6037 print a complete list of old and new set commands. ``help set FOO''
6038 will give a longer description of the variable FOO. ``show'' will show
6039 all of the variable descriptions and their current settings.
6041 confirm on/off: Enables warning questions for operations that are
6042 hard to recover from, e.g. rerunning the program while
6043 it is already running. Default is ON.
6045 editing on/off: Enables EMACS style command line editing
6046 of input. Previous lines can be recalled with
6047 control-P, the current line can be edited with control-B,
6048 you can search for commands with control-R, etc.
6051 history filename NAME: NAME is where the gdb command history
6052 will be stored. The default is .gdb_history,
6053 or the value of the environment variable
6056 history size N: The size, in commands, of the command history. The
6057 default is 256, or the value of the environment variable
6060 history save on/off: If this value is set to ON, the history file will
6061 be saved after exiting gdb. If set to OFF, the
6062 file will not be saved. The default is OFF.
6064 history expansion on/off: If this value is set to ON, then csh-like
6065 history expansion will be performed on
6066 command line input. The default is OFF.
6068 radix N: Sets the default radix for input and output. It can be set
6069 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6070 in the current radix, so "set radix 10" is always a no-op.
6072 height N: This integer value is the number of lines on a page. Default
6073 is 24, the current `stty rows'' setting, or the ``li#''
6074 setting from the termcap entry matching the environment
6077 width N: This integer value is the number of characters on a line.
6078 Default is 80, the current `stty cols'' setting, or the ``co#''
6079 setting from the termcap entry matching the environment
6082 Note: ``set screensize'' is obsolete. Use ``set height'' and
6083 ``set width'' instead.
6085 print address on/off: Print memory addresses in various command displays,
6086 such as stack traces and structure values. Gdb looks
6087 more ``symbolic'' if you turn this off; it looks more
6088 ``machine level'' with it on. Default is ON.
6090 print array on/off: Prettyprint arrays. New convenient format! Default
6093 print demangle on/off: Print C++ symbols in "source" form if on,
6096 print asm-demangle on/off: Same, for assembler level printouts
6099 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6102 * Support for Epoch Environment.
6104 The epoch environment is a version of Emacs v18 with windowing. One
6105 new command, ``inspect'', is identical to ``print'', except that if you
6106 are running in the epoch environment, the value is printed in its own
6110 * Support for Shared Libraries
6112 GDB can now debug programs and core files that use SunOS shared libraries.
6113 Symbols from a shared library cannot be referenced
6114 before the shared library has been linked with the program (this
6115 happens after you type ``run'' and before the function main() is entered).
6116 At any time after this linking (including when examining core files
6117 from dynamically linked programs), gdb reads the symbols from each
6118 shared library when you type the ``sharedlibrary'' command.
6119 It can be abbreviated ``share''.
6121 sharedlibrary REGEXP: Load shared object library symbols for files
6122 matching a unix regular expression. No argument
6123 indicates to load symbols for all shared libraries.
6125 info sharedlibrary: Status of loaded shared libraries.
6130 A watchpoint stops execution of a program whenever the value of an
6131 expression changes. Checking for this slows down execution
6132 tremendously whenever you are in the scope of the expression, but is
6133 quite useful for catching tough ``bit-spreader'' or pointer misuse
6134 problems. Some machines such as the 386 have hardware for doing this
6135 more quickly, and future versions of gdb will use this hardware.
6137 watch EXP: Set a watchpoint (breakpoint) for an expression.
6139 info watchpoints: Information about your watchpoints.
6141 delete N: Deletes watchpoint number N (same as breakpoints).
6142 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6143 enable N: Re-enables watchpoint number N (same as breakpoints).
6146 * C++ multiple inheritance
6148 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6151 * C++ exception handling
6153 Gdb now supports limited C++ exception handling. Besides the existing
6154 ability to breakpoint on an exception handler, gdb can breakpoint on
6155 the raising of an exception (before the stack is peeled back to the
6158 catch FOO: If there is a FOO exception handler in the dynamic scope,
6159 set a breakpoint to catch exceptions which may be raised there.
6160 Multiple exceptions (``catch foo bar baz'') may be caught.
6162 info catch: Lists all exceptions which may be caught in the
6163 current stack frame.
6166 * Minor command changes
6168 The command ``call func (arg, arg, ...)'' now acts like the print
6169 command, except it does not print or save a value if the function's result
6170 is void. This is similar to dbx usage.
6172 The ``up'' and ``down'' commands now always print the frame they end up
6173 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6174 frames without printing.
6176 * New directory command
6178 'dir' now adds directories to the FRONT of the source search path.
6179 The path starts off empty. Source files that contain debug information
6180 about the directory in which they were compiled can be found even
6181 with an empty path; Sun CC and GCC include this information. If GDB can't
6182 find your source file in the current directory, type "dir .".
6184 * Configuring GDB for compilation
6186 For normal use, type ``./configure host''. See README or gdb.texinfo
6189 GDB now handles cross debugging. If you are remotely debugging between
6190 two different machines, type ``./configure host -target=targ''.
6191 Host is the machine where GDB will run; targ is the machine
6192 where the program that you are debugging will run.