1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.10
6 * Support for tracepoints on aarch64-linux was added in GDBserver.
8 * The 'record instruction-history' command now indicates speculative execution
9 when using the Intel(R) Processor Trace recording format.
11 *** Changes in GDB 7.10
13 * Support for process record-replay and reverse debugging on aarch64*-linux*
14 targets has been added. GDB now supports recording of A64 instruction set
15 including advance SIMD instructions.
17 * Support for Sun's version of the "stabs" debug file format has been removed.
19 * GDB now honors the content of the file /proc/PID/coredump_filter
20 (PID is the process ID) on GNU/Linux systems. This file can be used
21 to specify the types of memory mappings that will be included in a
22 corefile. For more information, please refer to the manual page of
23 "core(5)". GDB also has a new command: "set use-coredump-filter
24 on|off". It allows to set whether GDB will read the content of the
25 /proc/PID/coredump_filter file when generating a corefile.
27 * The "info os" command on GNU/Linux can now display information on
29 "info os cpus" Listing of all cpus/cores on the system
31 * GDB has two new commands: "set serial parity odd|even|none" and
32 "show serial parity". These allows to set or show parity for the
35 * The "info source" command now displays the producer string if it was
36 present in the debug info. This typically includes the compiler version
37 and may include things like its command line arguments.
39 * The "info dll", an alias of the "info sharedlibrary" command,
40 is now available on all platforms.
42 * Directory names supplied to the "set sysroot" commands may be
43 prefixed with "target:" to tell GDB to access shared libraries from
44 the target system, be it local or remote. This replaces the prefix
45 "remote:". The default sysroot has been changed from "" to
46 "target:". "remote:" is automatically converted to "target:" for
47 backward compatibility.
49 * The system root specified by "set sysroot" will be prepended to the
50 filename of the main executable (if reported to GDB as absolute by
51 the operating system) when starting processes remotely, and when
52 attaching to already-running local or remote processes.
54 * GDB now supports automatic location and retrieval of executable
55 files from remote targets. Remote debugging can now be initiated
56 using only a "target remote" or "target extended-remote" command
57 (no "set sysroot" or "file" commands are required). See "New remote
60 * The "dump" command now supports verilog hex format.
62 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
64 * On GNU/Linux, GDB and gdbserver are now able to access executable
65 and shared library files without a "set sysroot" command when
66 attaching to processes running in different mount namespaces from
67 the debugger. This makes it possible to attach to processes in
68 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
69 See "New remote packets" below.
71 * The "tui reg" command now provides completion for all of the
72 available register groups, including target specific groups.
74 * The HISTSIZE environment variable is no longer read when determining
75 the size of GDB's command history. GDB now instead reads the dedicated
76 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
77 disables truncation of command history. Non-numeric values of GDBHISTSIZE
82 ** Memory ports can now be unbuffered.
86 ** gdb.Objfile objects have a new attribute "username",
87 which is the name of the objfile as specified by the user,
88 without, for example, resolving symlinks.
89 ** You can now write frame unwinders in Python.
90 ** gdb.Type objects have a new method "optimized_out",
91 returning optimized out gdb.Value instance of this type.
92 ** gdb.Value objects have new methods "reference_value" and
93 "const_value" which return a reference to the value and a
94 "const" version of the value respectively.
98 maint print symbol-cache
99 Print the contents of the symbol cache.
101 maint print symbol-cache-statistics
102 Print statistics of symbol cache usage.
104 maint flush-symbol-cache
105 Flush the contents of the symbol cache.
109 Start branch trace recording using Branch Trace Store (BTS) format.
112 Evaluate expression by using the compiler and print result.
116 Explicit commands for enabling and disabling tui mode.
119 set mpx bound on i386 and amd64
120 Support for bound table investigation on Intel(R) MPX enabled applications.
124 Start branch trace recording using Intel(R) Processor Trace format.
127 Print information about branch tracing internals.
129 maint btrace packet-history
130 Print the raw branch tracing data.
132 maint btrace clear-packet-history
133 Discard the stored raw branch tracing data.
136 Discard all branch tracing data. It will be fetched and processed
137 anew by the next "record" command.
142 Renamed from "set debug dwarf2-die".
144 Renamed from "show debug dwarf2-die".
147 Renamed from "set debug dwarf2-read".
148 show debug dwarf-read
149 Renamed from "show debug dwarf2-read".
151 maint set dwarf always-disassemble
152 Renamed from "maint set dwarf2 always-disassemble".
153 maint show dwarf always-disassemble
154 Renamed from "maint show dwarf2 always-disassemble".
156 maint set dwarf max-cache-age
157 Renamed from "maint set dwarf2 max-cache-age".
158 maint show dwarf max-cache-age
159 Renamed from "maint show dwarf2 max-cache-age".
162 show debug dwarf-line
163 Control display of debugging info regarding DWARF line processing.
167 Set the maximum number of candidates to be considered during
168 completion. The default value is 200. This limit allows GDB
169 to avoid generating large completion lists, the computation of
170 which can cause the debugger to become temporarily unresponsive.
172 set history remove-duplicates
173 show history remove-duplicates
174 Control the removal of duplicate history entries.
176 maint set symbol-cache-size
177 maint show symbol-cache-size
178 Control the size of the symbol cache.
180 set|show record btrace bts buffer-size
181 Set and show the size of the ring buffer used for branch tracing in
183 The obtained size may differ from the requested size. Use "info
184 record" to see the obtained buffer size.
186 set debug linux-namespaces
187 show debug linux-namespaces
188 Control display of debugging info regarding Linux namespaces.
190 set|show record btrace pt buffer-size
191 Set and show the size of the ring buffer used for branch tracing in
192 Intel(R) Processor Trace format.
193 The obtained size may differ from the requested size. Use "info
194 record" to see the obtained buffer size.
196 maint set|show btrace pt skip-pad
197 Set and show whether PAD packets are skipped when computing the
200 * The command 'thread apply all' can now support new option '-ascending'
201 to call its specified command for all threads in ascending order.
203 * Python/Guile scripting
205 ** GDB now supports auto-loading of Python/Guile scripts contained in the
206 special section named `.debug_gdb_scripts'.
210 qXfer:btrace-conf:read
211 Return the branch trace configuration for the current thread.
213 Qbtrace-conf:bts:size
214 Set the requested ring buffer size for branch tracing in BTS format.
217 Enable Intel(R) Procesor Trace-based branch tracing for the current
218 process. The remote stub reports support for this packet to GDB's
222 Set the requested ring buffer size for branch tracing in Intel(R) Processor
226 Indicates a memory breakpoint instruction was executed, irrespective
227 of whether it was GDB that planted the breakpoint or the breakpoint
228 is hardcoded in the program. This is required for correct non-stop
232 Indicates the target stopped for a hardware breakpoint. This is
233 required for correct non-stop mode operation.
236 Return information about files on the remote system.
239 Return the full absolute name of the file that was executed to
240 create a process running on the remote system.
243 Select the filesystem on which vFile: operations with filename
244 arguments will operate. This is required for GDB to be able to
245 access files on remote targets where the remote stub does not
246 share a common filesystem with the inferior(s).
249 Indicates that a fork system call was executed.
252 Indicates that a vfork system call was executed.
254 vforkdone stop reason
255 Indicates that a vfork child of the specified process has executed
256 an exec or exit, allowing the vfork parent to resume execution.
258 fork-events and vfork-events features in qSupported
259 The qSupported packet allows GDB to request support for fork and
260 vfork events using new 'gdbfeatures' fork-events and vfork-events,
261 and the qSupported response can contain the corresponding
262 'stubfeatures'. Set and show commands can be used to display
263 whether these features are enabled.
265 * Extended-remote fork events
267 ** GDB now has support for fork events on extended-remote Linux
268 targets. For targets with Linux kernels 2.5.60 and later, this
269 enables follow-fork-mode and detach-on-fork for both fork and
270 vfork, as well as fork and vfork catchpoints.
272 * The info record command now shows the recording format and the
273 branch tracing configuration for the current thread when using
274 the btrace record target.
275 For the BTS format, it shows the ring buffer size.
277 * GDB now has support for DTrace USDT (Userland Static Defined
278 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
280 * GDB now supports access to vector registers on S/390 GNU/Linux
283 * Removed command line options
285 -xdb HP-UX XDB compatibility mode.
287 * Removed targets and native configurations
289 HP/PA running HP-UX hppa*-*-hpux*
290 Itanium running HP-UX ia64-*-hpux*
292 * New configure options
295 This configure option allows the user to build GDB with support for
296 Intel(R) Processor Trace (default: auto). This requires libipt.
298 --with-libipt-prefix=PATH
299 Specify the path to the version of libipt that GDB should use.
300 $PATH/include should contain the intel-pt.h header and
301 $PATH/lib should contain the libipt.so library.
303 *** Changes in GDB 7.9.1
307 ** Xmethods can now specify a result type.
309 *** Changes in GDB 7.9
311 * GDB now supports hardware watchpoints on x86 GNU Hurd.
315 ** You can now access frame registers from Python scripts.
316 ** New attribute 'producer' for gdb.Symtab objects.
317 ** gdb.Objfile objects have a new attribute "progspace",
318 which is the gdb.Progspace object of the containing program space.
319 ** gdb.Objfile objects have a new attribute "owner".
320 ** gdb.Objfile objects have a new attribute "build_id",
321 which is the build ID generated when the file was built.
322 ** gdb.Objfile objects have a new method "add_separate_debug_file".
323 ** A new event "gdb.clear_objfiles" has been added, triggered when
324 selecting a new file to debug.
325 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
326 ** New function gdb.lookup_objfile.
328 New events which are triggered when GDB modifies the state of the
331 ** gdb.events.inferior_call_pre: Function call is about to be made.
332 ** gdb.events.inferior_call_post: Function call has just been made.
333 ** gdb.events.memory_changed: A memory location has been altered.
334 ** gdb.events.register_changed: A register has been altered.
336 * New Python-based convenience functions:
338 ** $_caller_is(name [, number_of_frames])
339 ** $_caller_matches(regexp [, number_of_frames])
340 ** $_any_caller_is(name [, number_of_frames])
341 ** $_any_caller_matches(regexp [, number_of_frames])
343 * GDB now supports the compilation and injection of source code into
344 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
345 to compile the source code to object code, and if successful, inject
346 and execute that code within the current context of the inferior.
347 Currently the C language is supported. The commands used to
348 interface with this new feature are:
350 compile code [-raw|-r] [--] [source code]
351 compile file [-raw|-r] filename
355 demangle [-l language] [--] name
356 Demangle "name" in the specified language, or the current language
357 if elided. This command is renamed from the "maint demangle" command.
358 The latter is kept as a no-op to avoid "maint demangle" being interpreted
359 as "maint demangler-warning".
361 queue-signal signal-name-or-number
362 Queue a signal to be delivered to the thread when it is resumed.
364 add-auto-load-scripts-directory directory
365 Add entries to the list of directories from which to load auto-loaded
368 maint print user-registers
369 List all currently available "user" registers.
371 compile code [-r|-raw] [--] [source code]
372 Compile, inject, and execute in the inferior the executable object
373 code produced by compiling the provided source code.
375 compile file [-r|-raw] filename
376 Compile and inject into the inferior the executable object code
377 produced by compiling the source code stored in the filename
380 * On resume, GDB now always passes the signal the program had stopped
381 for to the thread the signal was sent to, even if the user changed
382 threads before resuming. Previously GDB would often (but not
383 always) deliver the signal to the thread that happens to be current
386 * Conversely, the "signal" command now consistently delivers the
387 requested signal to the current thread. GDB now asks for
388 confirmation if the program had stopped for a signal and the user
389 switched threads meanwhile.
391 * "breakpoint always-inserted" modes "off" and "auto" merged.
393 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
394 won't remove breakpoints from the target until all threads stop,
395 even in non-stop mode. The "auto" mode has been removed, and "off"
396 is now the default mode.
400 set debug symbol-lookup
401 show debug symbol-lookup
402 Control display of debugging info regarding symbol lookup.
406 ** The -list-thread-groups command outputs an exit-code field for
407 inferiors that have exited.
411 MIPS SDE mips*-sde*-elf*
415 Support for these obsolete configurations has been removed.
417 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
418 SGI Irix-5.x mips-*-irix5*
419 SGI Irix-6.x mips-*-irix6*
420 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
421 VAX running Ultrix vax-*-ultrix*
423 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
424 and "assf"), have been removed. Use the "sharedlibrary" command, or
425 its alias "share", instead.
427 *** Changes in GDB 7.8
429 * New command line options
432 This is an alias for the --data-directory option.
434 * GDB supports printing and modifying of variable length automatic arrays
435 as specified in ISO C99.
437 * The ARM simulator now supports instruction level tracing
438 with or without disassembly.
442 GDB now has support for scripting using Guile. Whether this is
443 available is determined at configure time.
444 Guile version 2.0 or greater is required.
445 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
447 * New commands (for set/show, see "New options" below)
451 Invoke CODE by passing it to the Guile interpreter.
455 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
457 info auto-load guile-scripts [regexp]
458 Print the list of automatically loaded Guile scripts.
460 * The source command is now capable of sourcing Guile scripts.
461 This feature is dependent on the debugger being built with Guile support.
465 set print symbol-loading (off|brief|full)
466 show print symbol-loading
467 Control whether to print informational messages when loading symbol
468 information for a file. The default is "full", but when debugging
469 programs with large numbers of shared libraries the amount of output
472 set guile print-stack (none|message|full)
473 show guile print-stack
474 Show a stack trace when an error is encountered in a Guile script.
476 set auto-load guile-scripts (on|off)
477 show auto-load guile-scripts
478 Control auto-loading of Guile script files.
480 maint ada set ignore-descriptive-types (on|off)
481 maint ada show ignore-descriptive-types
482 Control whether the debugger should ignore descriptive types in Ada
483 programs. The default is not to ignore the descriptive types. See
484 the user manual for more details on descriptive types and the intended
485 usage of this option.
487 set auto-connect-native-target
489 Control whether GDB is allowed to automatically connect to the
490 native target for the run, attach, etc. commands when not connected
491 to any target yet. See also "target native" below.
493 set record btrace replay-memory-access (read-only|read-write)
494 show record btrace replay-memory-access
495 Control what memory accesses are allowed during replay.
497 maint set target-async (on|off)
498 maint show target-async
499 This controls whether GDB targets operate in synchronous or
500 asynchronous mode. Normally the default is asynchronous, if it is
501 available; but this can be changed to more easily debug problems
502 occurring only in synchronous mode.
504 set mi-async (on|off)
506 Control whether MI asynchronous mode is preferred. This supersedes
507 "set target-async" of previous GDB versions.
509 * "set target-async" is deprecated as a CLI option and is now an alias
510 for "set mi-async" (only puts MI into async mode).
512 * Background execution commands (e.g., "c&", "s&", etc.) are now
513 possible ``out of the box'' if the target supports them. Previously
514 the user would need to explicitly enable the possibility with the
515 "set target-async on" command.
517 * New features in the GDB remote stub, GDBserver
519 ** New option --debug-format=option1[,option2,...] allows one to add
520 additional text to each output. At present only timestamps
521 are supported: --debug-format=timestamps.
522 Timestamps can also be turned on with the
523 "monitor set debug-format timestamps" command from GDB.
525 * The 'record instruction-history' command now starts counting instructions
526 at one. This also affects the instruction ranges reported by the
527 'record function-call-history' command when given the /i modifier.
529 * The command 'record function-call-history' supports a new modifier '/c' to
530 indent the function names based on their call stack depth.
531 The fields for the '/i' and '/l' modifier have been reordered.
532 The source line range is now prefixed with 'at'.
533 The instruction range is now prefixed with 'inst'.
534 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
535 "record instruction-history" and "list" commands.
537 * The ranges given as arguments to the 'record function-call-history' and
538 'record instruction-history' commands are now inclusive.
540 * The btrace record target now supports the 'record goto' command.
541 For locations inside the execution trace, the back trace is computed
542 based on the information stored in the execution trace.
544 * The btrace record target supports limited reverse execution and replay.
545 The target does not record data and therefore does not allow reading
548 * The "catch syscall" command now works on s390*-linux* targets.
550 * The "compare-sections" command is no longer specific to target
551 remote. It now works with all targets.
553 * All native targets are now consistently called "native".
554 Consequently, the "target child", "target GNU", "target djgpp",
555 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
556 commands have been replaced with "target native". The QNX/NTO port
557 leaves the "procfs" target in place and adds a "native" target for
558 consistency with other ports. The impact on users should be minimal
559 as these commands previously either throwed an error, or were
560 no-ops. The target's name is visible in the output of the following
561 commands: "help target", "info target", "info files", "maint print
564 * The "target native" command now connects to the native target. This
565 can be used to launch native programs even when "set
566 auto-connect-native-target" is set to off.
568 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
570 * Support for Intel(R) AVX-512 registers on GNU/Linux.
571 Support displaying and modifying Intel(R) AVX-512 registers
572 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
576 qXfer:btrace:read's annex
577 The qXfer:btrace:read packet supports a new annex 'delta' to read
578 branch trace incrementally.
582 ** Valid Python operations on gdb.Value objects representing
583 structs/classes invoke the corresponding overloaded operators if
585 ** New `Xmethods' feature in the Python API. Xmethods are
586 additional methods or replacements for existing methods of a C++
587 class. This feature is useful for those cases where a method
588 defined in C++ source code could be inlined or optimized out by
589 the compiler, making it unavailable to GDB.
592 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
594 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
595 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
596 its alias "share", instead.
598 * The commands "set remotebaud" and "show remotebaud" are no longer
599 supported. Use "set serial baud" and "show serial baud" (respectively)
604 ** A new option "-gdb-set mi-async" replaces "-gdb-set
605 target-async". The latter is left as a deprecated alias of the
606 former for backward compatibility. If the target supports it,
607 CLI background execution commands are now always possible by
608 default, independently of whether the frontend stated a
609 preference for asynchronous execution with "-gdb-set mi-async".
610 Previously "-gdb-set target-async off" affected both MI execution
611 commands and CLI execution commands.
613 *** Changes in GDB 7.7
615 * Improved support for process record-replay and reverse debugging on
616 arm*-linux* targets. Support for thumb32 and syscall instruction
617 recording has been added.
619 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
621 * GDB now supports Fission DWP file format version 2.
622 http://gcc.gnu.org/wiki/DebugFission
624 * New convenience function "$_isvoid", to check whether an expression
625 is void. A void expression is an expression where the type of the
626 result is "void". For example, some convenience variables may be
627 "void" when evaluated (e.g., "$_exitcode" before the execution of
628 the program being debugged; or an undefined convenience variable).
629 Another example, when calling a function whose return type is
632 * The "maintenance print objfiles" command now takes an optional regexp.
634 * The "catch syscall" command now works on arm*-linux* targets.
636 * GDB now consistently shows "<not saved>" when printing values of
637 registers the debug info indicates have not been saved in the frame
638 and there's nowhere to retrieve them from
639 (callee-saved/call-clobbered registers):
644 (gdb) info registers rax
647 Before, the former would print "<optimized out>", and the latter
648 "*value not available*".
650 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
655 ** Frame filters and frame decorators have been added.
656 ** Temporary breakpoints are now supported.
657 ** Line tables representation has been added.
658 ** New attribute 'parent_type' for gdb.Field objects.
659 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
660 ** New attribute 'name' for gdb.Type objects.
664 Nios II ELF nios2*-*-elf
665 Nios II GNU/Linux nios2*-*-linux
666 Texas Instruments MSP430 msp430*-*-elf
668 * Removed native configurations
670 Support for these a.out NetBSD and OpenBSD obsolete configurations has
671 been removed. ELF variants of these configurations are kept supported.
673 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
674 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
675 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
676 i[34567]86-*-openbsd3.[0-3]
677 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
678 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
679 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
683 Like "catch throw", but catches a re-thrown exception.
685 Renamed from old "maint check-symtabs".
687 Perform consistency checks on symtabs.
689 Expand symtabs matching an optional regexp.
692 Display the details of GDB configure-time options.
694 maint set|show per-command
695 maint set|show per-command space
696 maint set|show per-command time
697 maint set|show per-command symtab
698 Enable display of per-command gdb resource usage.
700 remove-symbol-file FILENAME
701 remove-symbol-file -a ADDRESS
702 Remove a symbol file added via add-symbol-file. The file to remove
703 can be identified by its filename or by an address that lies within
704 the boundaries of this symbol file in memory.
707 info exceptions REGEXP
708 Display the list of Ada exceptions defined in the program being
709 debugged. If provided, only the exceptions whose names match REGEXP
714 set debug symfile off|on
716 Control display of debugging info regarding reading symbol files and
717 symbol tables within those files
719 set print raw frame-arguments
720 show print raw frame-arguments
721 Set/show whether to print frame arguments in raw mode,
722 disregarding any defined pretty-printers.
724 set remote trace-status-packet
725 show remote trace-status-packet
726 Set/show the use of remote protocol qTStatus packet.
730 Control display of debugging messages related to Nios II targets.
734 Control whether target-assisted range stepping is enabled.
736 set startup-with-shell
737 show startup-with-shell
738 Specifies whether Unix child processes are started via a shell or
743 Use the target memory cache for accesses to the code segment. This
744 improves performance of remote debugging (particularly disassembly).
746 * You can now use a literal value 'unlimited' for options that
747 interpret 0 or -1 as meaning "unlimited". E.g., "set
748 trace-buffer-size unlimited" is now an alias for "set
749 trace-buffer-size -1" and "set height unlimited" is now an alias for
752 * The "set debug symtab-create" debugging option of GDB has been changed to
753 accept a verbosity level. 0 means "off", 1 provides basic debugging
754 output, and values of 2 or greater provides more verbose output.
756 * New command-line options
758 Display the details of GDB configure-time options.
760 * The command 'tsave' can now support new option '-ctf' to save trace
761 buffer in Common Trace Format.
763 * Newly installed $prefix/bin/gcore acts as a shell interface for the
766 * GDB now implements the the C++ 'typeid' operator.
768 * The new convenience variable $_exception holds the exception being
769 thrown or caught at an exception-related catchpoint.
771 * The exception-related catchpoints, like "catch throw", now accept a
772 regular expression which can be used to filter exceptions by type.
774 * The new convenience variable $_exitsignal is automatically set to
775 the terminating signal number when the program being debugged dies
776 due to an uncaught signal.
780 ** All MI commands now accept an optional "--language" option.
781 Support for this feature can be verified by using the "-list-features"
782 command, which should contain "language-option".
784 ** The new command -info-gdb-mi-command allows the user to determine
785 whether a GDB/MI command is supported or not.
787 ** The "^error" result record returned when trying to execute an undefined
788 GDB/MI command now provides a variable named "code" whose content is the
789 "undefined-command" error code. Support for this feature can be verified
790 by using the "-list-features" command, which should contain
791 "undefined-command-error-code".
793 ** The -trace-save MI command can optionally save trace buffer in Common
796 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
798 ** The command -data-list-register-values now accepts an optional
799 "--skip-unavailable" option. When used, only the available registers
802 ** The new command -trace-frame-collected dumps collected variables,
803 computed expressions, tvars, memory and registers in a traceframe.
805 ** The commands -stack-list-locals, -stack-list-arguments and
806 -stack-list-variables now accept an option "--skip-unavailable".
807 When used, only the available locals or arguments are displayed.
809 ** The -exec-run command now accepts an optional "--start" option.
810 When used, the command follows the same semantics as the "start"
811 command, stopping the program's execution at the start of its
812 main subprogram. Support for this feature can be verified using
813 the "-list-features" command, which should contain
814 "exec-run-start-option".
816 ** The new commands -catch-assert and -catch-exceptions insert
817 catchpoints stopping the program when Ada exceptions are raised.
819 ** The new command -info-ada-exceptions provides the equivalent of
820 the new "info exceptions" command.
822 * New system-wide configuration scripts
823 A GDB installation now provides scripts suitable for use as system-wide
824 configuration scripts for the following systems:
828 * GDB now supports target-assigned range stepping with remote targets.
829 This improves the performance of stepping source lines by reducing
830 the number of control packets from/to GDB. See "New remote packets"
833 * GDB now understands the element 'tvar' in the XML traceframe info.
834 It has the id of the collected trace state variables.
836 * On S/390 targets that provide the transactional-execution feature,
837 the program interruption transaction diagnostic block (TDB) is now
838 represented as a number of additional "registers" in GDB.
844 The vCont packet supports a new 'r' action, that tells the remote
845 stub to step through an address range itself, without GDB
846 involvemement at each single-step.
848 qXfer:libraries-svr4:read's annex
849 The previously unused annex of the qXfer:libraries-svr4:read packet
850 is now used to support passing an argument list. The remote stub
851 reports support for this argument list to GDB's qSupported query.
852 The defined arguments are "start" and "prev", used to reduce work
853 necessary for library list updating, resulting in significant
856 * New features in the GDB remote stub, GDBserver
858 ** GDBserver now supports target-assisted range stepping. Currently
859 enabled on x86/x86_64 GNU/Linux targets.
861 ** GDBserver now adds element 'tvar' in the XML in the reply to
862 'qXfer:traceframe-info:read'. It has the id of the collected
863 trace state variables.
865 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
868 * New 'z' formatter for printing and examining memory, this displays the
869 value as hexadecimal zero padded on the left to the size of the type.
871 * GDB can now use Windows x64 unwinding data.
873 * The "set remotebaud" command has been replaced by "set serial baud".
874 Similarly, "show remotebaud" has been replaced by "show serial baud".
875 The "set remotebaud" and "show remotebaud" commands are still available
876 to provide backward compatibility with older versions of GDB.
878 *** Changes in GDB 7.6
880 * Target record has been renamed to record-full.
881 Record/replay is now enabled with the "record full" command.
882 This also affects settings that are associated with full record/replay
883 that have been moved from "set/show record" to "set/show record full":
885 set|show record full insn-number-max
886 set|show record full stop-at-limit
887 set|show record full memory-query
889 * A new record target "record-btrace" has been added. The new target
890 uses hardware support to record the control-flow of a process. It
891 does not support replaying the execution, but it implements the
892 below new commands for investigating the recorded execution log.
893 This new recording method can be enabled using:
897 The "record-btrace" target is only available on Intel Atom processors
898 and requires a Linux kernel 2.6.32 or later.
900 * Two new commands have been added for record/replay to give information
901 about the recorded execution without having to replay the execution.
902 The commands are only supported by "record btrace".
904 record instruction-history prints the execution history at
905 instruction granularity
907 record function-call-history prints the execution history at
910 * New native configurations
912 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
913 FreeBSD/powerpc powerpc*-*-freebsd
914 x86_64/Cygwin x86_64-*-cygwin*
915 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
919 ARM AArch64 aarch64*-*-elf
920 ARM AArch64 GNU/Linux aarch64*-*-linux
921 Lynx 178 PowerPC powerpc-*-lynx*178
922 x86_64/Cygwin x86_64-*-cygwin*
923 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
925 * If the configured location of system.gdbinit file (as given by the
926 --with-system-gdbinit option at configure time) is in the
927 data-directory (as specified by --with-gdb-datadir at configure
928 time) or in one of its subdirectories, then GDB will look for the
929 system-wide init file in the directory specified by the
930 --data-directory command-line option.
932 * New command line options:
934 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
935 other initialization files, unlike -nx which disables all of them.
937 * Removed command line options
939 -epoch This was used by the gdb mode in Epoch, an ancient fork of
942 * The 'ptype' and 'whatis' commands now accept an argument to control
945 * 'info proc' now works on some core files.
949 ** Vectors can be created with gdb.Type.vector.
951 ** Python's atexit.register now works in GDB.
953 ** Types can be pretty-printed via a Python API.
955 ** Python 3 is now supported (in addition to Python 2.4 or later)
957 ** New class gdb.Architecture exposes GDB's internal representation
958 of architecture in the Python API.
960 ** New method Frame.architecture returns the gdb.Architecture object
961 corresponding to the frame's architecture.
963 * New Python-based convenience functions:
965 ** $_memeq(buf1, buf2, length)
966 ** $_streq(str1, str2)
968 ** $_regex(str, regex)
970 * The 'cd' command now defaults to using '~' (the home directory) if not
973 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
974 default for GCC since November 2000.
976 * The command 'forward-search' can now be abbreviated as 'fo'.
978 * The command 'info tracepoints' can now display 'installed on target'
979 or 'not installed on target' for each non-pending location of tracepoint.
981 * New configure options
983 --enable-libmcheck/--disable-libmcheck
984 By default, development versions are built with -lmcheck on hosts
985 that support it, in order to help track memory corruption issues.
986 Release versions, on the other hand, are built without -lmcheck
987 by default. The --enable-libmcheck/--disable-libmcheck configure
988 options allow the user to override that default.
989 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
990 This configure option allows the user to build GDB with
991 libbabeltrace using which GDB can read Common Trace Format data.
993 * New commands (for set/show, see "New options" below)
996 Catch signals. This is similar to "handle", but allows commands and
997 conditions to be attached.
1000 List the BFDs known to GDB.
1002 python-interactive [command]
1004 Start a Python interactive prompt, or evaluate the optional command
1005 and print the result of expressions.
1008 "py" is a new alias for "python".
1010 enable type-printer [name]...
1011 disable type-printer [name]...
1012 Enable or disable type printers.
1016 ** For the Renesas Super-H architecture, the "regs" command has been removed
1017 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1022 set print type methods (on|off)
1023 show print type methods
1024 Control whether method declarations are displayed by "ptype".
1025 The default is to show them.
1027 set print type typedefs (on|off)
1028 show print type typedefs
1029 Control whether typedef definitions are displayed by "ptype".
1030 The default is to show them.
1032 set filename-display basename|relative|absolute
1033 show filename-display
1034 Control the way in which filenames is displayed.
1035 The default is "relative", which preserves previous behavior.
1037 set trace-buffer-size
1038 show trace-buffer-size
1039 Request target to change the size of trace buffer.
1041 set remote trace-buffer-size-packet auto|on|off
1042 show remote trace-buffer-size-packet
1043 Control the use of the remote protocol `QTBuffer:size' packet.
1047 Control display of debugging messages related to ARM AArch64.
1050 set debug coff-pe-read
1051 show debug coff-pe-read
1052 Control display of debugging messages related to reading of COFF/PE
1057 Control display of debugging messages related to Mach-O symbols
1060 set debug notification
1061 show debug notification
1062 Control display of debugging info for async remote notification.
1066 ** Command parameter changes are now notified using new async record
1067 "=cmd-param-changed".
1068 ** Trace frame changes caused by command "tfind" are now notified using
1069 new async record "=traceframe-changed".
1070 ** The creation, deletion and modification of trace state variables
1071 are now notified using new async records "=tsv-created",
1072 "=tsv-deleted" and "=tsv-modified".
1073 ** The start and stop of process record are now notified using new
1074 async record "=record-started" and "=record-stopped".
1075 ** Memory changes are now notified using new async record
1077 ** The data-disassemble command response will include a "fullname" field
1078 containing the absolute file name when source has been requested.
1079 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1080 command, to allow pattern filling of memory areas.
1081 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1082 library load/unload events.
1083 ** The response to breakpoint commands and breakpoint async records
1084 includes an "installed" field containing a boolean state about each
1085 non-pending tracepoint location is whether installed on target or not.
1086 ** Output of the "-trace-status" command includes a "trace-file" field
1087 containing the name of the trace file being examined. This field is
1088 optional, and only present when examining a trace file.
1089 ** The "fullname" field is now always present along with the "file" field,
1090 even if the file cannot be found by GDB.
1092 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1093 You must have the LZMA library available when configuring GDB for this
1094 feature to be enabled. For more information, see:
1095 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1097 * New remote packets
1100 Set the size of trace buffer. The remote stub reports support for this
1101 packet to gdb's qSupported query.
1104 Enable Branch Trace Store (BTS)-based branch tracing for the current
1105 thread. The remote stub reports support for this packet to gdb's
1109 Disable branch tracing for the current thread. The remote stub reports
1110 support for this packet to gdb's qSupported query.
1113 Read the traced branches for the current thread. The remote stub
1114 reports support for this packet to gdb's qSupported query.
1116 *** Changes in GDB 7.5
1118 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1119 for more x32 ABI info.
1121 * GDB now supports access to MIPS DSP registers on Linux targets.
1123 * GDB now supports debugging microMIPS binaries.
1125 * The "info os" command on GNU/Linux can now display information on
1126 several new classes of objects managed by the operating system:
1127 "info os procgroups" lists process groups
1128 "info os files" lists file descriptors
1129 "info os sockets" lists internet-domain sockets
1130 "info os shm" lists shared-memory regions
1131 "info os semaphores" lists semaphores
1132 "info os msg" lists message queues
1133 "info os modules" lists loaded kernel modules
1135 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1136 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1137 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1138 options and inspect the probe arguments using the new $_probe_arg family
1139 of convenience variables. You can obtain more information about SystemTap
1140 in <http://sourceware.org/systemtap/>.
1142 * GDB now supports reversible debugging on ARM, it allows you to
1143 debug basic ARM and THUMB instructions, and provides
1144 record/replay support.
1146 * The option "symbol-reloading" has been deleted as it is no longer used.
1150 ** GDB commands implemented in Python can now be put in command class
1153 ** The "maint set python print-stack on|off" is now deleted.
1155 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1156 apply "flag enum"-style pretty-printing to any enum.
1158 ** gdb.lookup_symbol can now work when there is no current frame.
1160 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1161 the source at which the symbol was defined.
1163 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1164 method 'value'. The former indicates whether the symbol needs a
1165 frame in order to compute its value, and the latter computes the
1168 ** A new method 'referenced_value' on gdb.Value objects which can
1169 dereference pointer as well as C++ reference values.
1171 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1172 which return the global and static blocks (as gdb.Block objects),
1173 of the underlying symbol table, respectively.
1175 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1176 object associated with a PC value.
1178 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1179 of the address range occupied by code for the current source line.
1181 * Go language support.
1182 GDB now supports debugging programs written in the Go programming
1185 * GDBserver now supports stdio connections.
1186 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1188 * The binary "gdbtui" can no longer be built or installed.
1189 Use "gdb -tui" instead.
1191 * GDB will now print "flag" enums specially. A flag enum is one where
1192 all the enumerator values have no bits in common when pairwise
1193 "and"ed. When printing a value whose type is a flag enum, GDB will
1194 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1195 (gdb) print (enum E) 3
1198 * The filename part of a linespec will now match trailing components
1199 of a source file name. For example, "break gcc/expr.c:1000" will
1200 now set a breakpoint in build/gcc/expr.c, but not
1201 build/libcpp/expr.c.
1203 * The "info proc" and "generate-core-file" commands will now also
1204 work on remote targets connected to GDBserver on Linux.
1206 * The command "info catch" has been removed. It has been disabled
1207 since December 2007.
1209 * The "catch exception" and "catch assert" commands now accept
1210 a condition at the end of the command, much like the "break"
1211 command does. For instance:
1213 (gdb) catch exception Constraint_Error if Barrier = True
1215 Previously, it was possible to add a condition to such catchpoints,
1216 but it had to be done as a second step, after the catchpoint had been
1217 created, using the "condition" command.
1219 * The "info static-tracepoint-marker" command will now also work on
1220 native Linux targets with in-process agent.
1222 * GDB can now set breakpoints on inlined functions.
1224 * The .gdb_index section has been updated to include symbols for
1225 inlined functions. GDB will ignore older .gdb_index sections by
1226 default, which could cause symbol files to be loaded more slowly
1227 until their .gdb_index sections can be recreated. The new command
1228 "set use-deprecated-index-sections on" will cause GDB to use any older
1229 .gdb_index sections it finds. This will restore performance, but the
1230 ability to set breakpoints on inlined functions will be lost in symbol
1231 files with older .gdb_index sections.
1233 The .gdb_index section has also been updated to record more information
1234 about each symbol. This speeds up the "info variables", "info functions"
1235 and "info types" commands when used with programs having the .gdb_index
1236 section, as well as speeding up debugging with shared libraries using
1237 the .gdb_index section.
1239 * Ada support for GDB/MI Variable Objects has been added.
1241 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1246 ** New command -info-os is the MI equivalent of "info os".
1248 ** Output logs ("set logging" and related) now include MI output.
1252 ** "set use-deprecated-index-sections on|off"
1253 "show use-deprecated-index-sections on|off"
1254 Controls the use of deprecated .gdb_index sections.
1256 ** "catch load" and "catch unload" can be used to stop when a shared
1257 library is loaded or unloaded, respectively.
1259 ** "enable count" can be used to auto-disable a breakpoint after
1262 ** "info vtbl" can be used to show the virtual method tables for
1263 C++ and Java objects.
1265 ** "explore" and its sub commands "explore value" and "explore type"
1266 can be used to recursively explore values and types of
1267 expressions. These commands are available only if GDB is
1268 configured with '--with-python'.
1270 ** "info auto-load" shows status of all kinds of auto-loaded files,
1271 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1272 sequences of commands files, "info auto-load python-scripts"
1273 shows status of auto-loading Python script files,
1274 "info auto-load local-gdbinit" shows status of loading init file
1275 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1276 status of inferior specific thread debugging shared library loading.
1278 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1279 and "show auto-load-scripts" commands have been deprecated, use their
1280 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1281 and "show auto-load python-scripts" counterparts instead.
1283 ** "dprintf location,format,args..." creates a dynamic printf, which
1284 is basically a breakpoint that does a printf and immediately
1285 resumes your program's execution, so it is like a printf that you
1286 can insert dynamically at runtime instead of at compiletime.
1288 ** "set print symbol"
1290 Controls whether GDB attempts to display the symbol, if any,
1291 corresponding to addresses it prints. This defaults to "on", but
1292 you can set it to "off" to restore GDB's previous behavior.
1294 * Deprecated commands
1296 ** For the Renesas Super-H architecture, the "regs" command has been
1297 deprecated, and "info all-registers" should be used instead.
1301 Renesas RL78 rl78-*-elf
1302 HP OpenVMS ia64 ia64-hp-openvms*
1304 * GDBserver supports evaluation of breakpoint conditions. When
1305 support is advertised by GDBserver, GDB may be told to send the
1306 breakpoint conditions in bytecode form to GDBserver. GDBserver
1307 will only report the breakpoint trigger to GDB when its condition
1312 set mips compression
1313 show mips compression
1314 Select the compressed ISA encoding used in functions that have no symbol
1315 information available. The encoding can be set to either of:
1318 and is updated automatically from ELF file flags if available.
1320 set breakpoint condition-evaluation
1321 show breakpoint condition-evaluation
1322 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1323 GDBserver ("target"). Default option "auto" chooses the most efficient
1325 This option can improve debugger efficiency depending on the speed of the
1329 Disable auto-loading globally.
1332 Show auto-loading setting of all kinds of auto-loaded files.
1334 set auto-load gdb-scripts on|off
1335 show auto-load gdb-scripts
1336 Control auto-loading of GDB canned sequences of commands files.
1338 set auto-load python-scripts on|off
1339 show auto-load python-scripts
1340 Control auto-loading of Python script files.
1342 set auto-load local-gdbinit on|off
1343 show auto-load local-gdbinit
1344 Control loading of init file (.gdbinit) from current directory.
1346 set auto-load libthread-db on|off
1347 show auto-load libthread-db
1348 Control auto-loading of inferior specific thread debugging shared library.
1350 set auto-load scripts-directory <dir1>[:<dir2>...]
1351 show auto-load scripts-directory
1352 Set a list of directories from which to load auto-loaded scripts.
1353 Automatically loaded Python scripts and GDB scripts are located in one
1354 of the directories listed by this option.
1355 The delimiter (':' above) may differ according to the host platform.
1357 set auto-load safe-path <dir1>[:<dir2>...]
1358 show auto-load safe-path
1359 Set a list of directories from which it is safe to auto-load files.
1360 The delimiter (':' above) may differ according to the host platform.
1362 set debug auto-load on|off
1363 show debug auto-load
1364 Control display of debugging info for auto-loading the files above.
1366 set dprintf-style gdb|call|agent
1368 Control the way in which a dynamic printf is performed; "gdb"
1369 requests a GDB printf command, while "call" causes dprintf to call a
1370 function in the inferior. "agent" requests that the target agent
1371 (such as GDBserver) do the printing.
1373 set dprintf-function <expr>
1374 show dprintf-function
1375 set dprintf-channel <expr>
1376 show dprintf-channel
1377 Set the function and optional first argument to the call when using
1378 the "call" style of dynamic printf.
1380 set disconnected-dprintf on|off
1381 show disconnected-dprintf
1382 Control whether agent-style dynamic printfs continue to be in effect
1383 after GDB disconnects.
1385 * New configure options
1387 --with-auto-load-dir
1388 Configure default value for the 'set auto-load scripts-directory'
1389 setting above. It defaults to '$debugdir:$datadir/auto-load',
1390 $debugdir representing global debugging info directories (available
1391 via 'show debug-file-directory') and $datadir representing GDB's data
1392 directory (available via 'show data-directory').
1394 --with-auto-load-safe-path
1395 Configure default value for the 'set auto-load safe-path' setting
1396 above. It defaults to the --with-auto-load-dir setting.
1398 --without-auto-load-safe-path
1399 Set 'set auto-load safe-path' to '/', effectively disabling this
1402 * New remote packets
1404 z0/z1 conditional breakpoints extension
1406 The z0/z1 breakpoint insertion packets have been extended to carry
1407 a list of conditional expressions over to the remote stub depending on the
1408 condition evaluation mode. The use of this extension can be controlled
1409 via the "set remote conditional-breakpoints-packet" command.
1413 Specify the signals which the remote stub may pass to the debugged
1414 program without GDB involvement.
1416 * New command line options
1418 --init-command=FILE, -ix Like --command, -x but execute it
1419 before loading inferior.
1420 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1421 execute it before loading inferior.
1423 *** Changes in GDB 7.4
1425 * GDB now handles ambiguous linespecs more consistently; the existing
1426 FILE:LINE support has been expanded to other types of linespecs. A
1427 breakpoint will now be set on all matching locations in all
1428 inferiors, and locations will be added or removed according to
1431 * GDB now allows you to skip uninteresting functions and files when
1432 stepping with the "skip function" and "skip file" commands.
1434 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1435 and "show remote hardware-watchpoint-length-limit". These allows to
1436 set or show the maximum length limit (in bytes) of a remote
1437 target hardware watchpoint.
1439 This allows e.g. to use "unlimited" hardware watchpoints with the
1440 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1441 watchpoints are slower than real hardware watchpoints but are
1442 significantly faster than gdb software watchpoints.
1446 ** The register_pretty_printer function in module gdb.printing now takes
1447 an optional `replace' argument. If True, the new printer replaces any
1450 ** The "maint set python print-stack on|off" command has been
1451 deprecated and will be deleted in GDB 7.5.
1452 A new command: "set python print-stack none|full|message" has
1453 replaced it. Additionally, the default for "print-stack" is
1454 now "message", which just prints the error message without
1457 ** A prompt substitution hook (prompt_hook) is now available to the
1460 ** A new Python module, gdb.prompt has been added to the GDB Python
1461 modules library. This module provides functionality for
1462 escape sequences in prompts (used by set/show
1463 extended-prompt). These escape sequences are replaced by their
1464 corresponding value.
1466 ** Python commands and convenience-functions located in
1467 'data-directory'/python/gdb/command and
1468 'data-directory'/python/gdb/function are now automatically loaded
1471 ** Blocks now provide four new attributes. global_block and
1472 static_block will return the global and static blocks
1473 respectively. is_static and is_global are boolean attributes
1474 that indicate if the block is one of those two types.
1476 ** Symbols now provide the "type" attribute, the type of the symbol.
1478 ** The "gdb.breakpoint" function has been deprecated in favor of
1481 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1482 of a function. This class is based on the "finish" command
1483 available in the CLI.
1485 ** Type objects for struct and union types now allow access to
1486 the fields using standard Python dictionary (mapping) methods.
1487 For example, "some_type['myfield']" now works, as does
1488 "some_type.items()".
1490 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1493 ** A new function, "deep_items" has been added to the gdb.types
1494 module in the GDB Python modules library. This function returns
1495 an iterator over the fields of a struct or union type. Unlike
1496 the standard Python "iteritems" method, it will recursively traverse
1497 any anonymous fields.
1501 ** "*stopped" events can report several new "reason"s, such as
1504 ** Breakpoint changes are now notified using new async records, like
1505 "=breakpoint-modified".
1507 ** New command -ada-task-info.
1509 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1510 $sdir specifies the default system locations of shared libraries.
1511 $pdir specifies the directory where the libpthread used by the application
1514 GDB no longer looks in $sdir and $pdir after it has searched the directories
1515 mentioned in libthread-db-search-path. If you want to search those
1516 directories, they must be specified in libthread-db-search-path.
1517 The default value of libthread-db-search-path on GNU/Linux and Solaris
1518 systems is now "$sdir:$pdir".
1520 $pdir is not supported by gdbserver, it is currently ignored.
1521 $sdir is supported by gdbserver.
1523 * New configure option --with-iconv-bin.
1524 When using the internationalization support like the one in the GNU C
1525 library, GDB will invoke the "iconv" program to get a list of supported
1526 character sets. If this program lives in a non-standard location, one can
1527 use this option to specify where to find it.
1529 * When natively debugging programs on PowerPC BookE processors running
1530 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1531 watchpoints, which specify a mask in addition to an address to watch.
1532 The mask specifies that some bits of an address (the bits which are
1533 reset in the mask) should be ignored when matching the address accessed
1534 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1535 section in the user manual for more details.
1537 * The new option --once causes GDBserver to stop listening for connections once
1538 the first connection is made. The listening port used by GDBserver will
1539 become available after that.
1541 * New commands "info macros" and "alias" have been added.
1543 * New function parameters suffix @entry specifies value of function parameter
1544 at the time the function got called. Entry values are available only since
1550 "!" is now an alias of the "shell" command.
1551 Note that no space is needed between "!" and SHELL COMMAND.
1555 watch EXPRESSION mask MASK_VALUE
1556 The watch command now supports the mask argument which allows creation
1557 of masked watchpoints, if the current architecture supports this feature.
1559 info auto-load-scripts [REGEXP]
1560 This command was formerly named "maintenance print section-scripts".
1561 It is now generally useful and is no longer a maintenance-only command.
1563 info macro [-all] [--] MACRO
1564 The info macro command has new options `-all' and `--'. The first for
1565 printing all definitions of a macro. The second for explicitly specifying
1566 the end of arguments and the beginning of the macro name in case the macro
1567 name starts with a hyphen.
1569 collect[/s] EXPRESSIONS
1570 The tracepoint collect command now takes an optional modifier "/s"
1571 that directs it to dereference pointer-to-character types and
1572 collect the bytes of memory up to a zero byte. The behavior is
1573 similar to what you see when you use the regular print command on a
1574 string. An optional integer following the "/s" sets a bound on the
1575 number of bytes that will be collected.
1578 The trace start command now interprets any supplied arguments as a
1579 note to be recorded with the trace run, with an effect similar to
1580 setting the variable trace-notes.
1583 The trace stop command now interprets any arguments as a note to be
1584 mentioned along with the tstatus report that the trace was stopped
1585 with a command. The effect is similar to setting the variable
1588 * Tracepoints can now be enabled and disabled at any time after a trace
1589 experiment has been started using the standard "enable" and "disable"
1590 commands. It is now possible to start a trace experiment with no enabled
1591 tracepoints; GDB will display a warning, but will allow the experiment to
1592 begin, assuming that tracepoints will be enabled as needed while the trace
1595 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1596 locations with 4-byte instructions, when they were previously
1597 limited to locations with instructions of 5 bytes or longer.
1601 set debug dwarf2-read
1602 show debug dwarf2-read
1603 Turns on or off display of debugging messages related to reading
1604 DWARF debug info. The default is off.
1606 set debug symtab-create
1607 show debug symtab-create
1608 Turns on or off display of debugging messages related to symbol table
1609 creation. The default is off.
1612 show extended-prompt
1613 Set the GDB prompt, and allow escape sequences to be inserted to
1614 display miscellaneous information (see 'help set extended-prompt'
1615 for the list of sequences). This prompt (and any information
1616 accessed through the escape sequences) is updated every time the
1617 prompt is displayed.
1619 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1620 show print entry-values
1621 Set printing of frame argument values at function entry. In some cases
1622 GDB can determine the value of function argument which was passed by the
1623 function caller, even if the value was modified inside the called function.
1625 set debug entry-values
1626 show debug entry-values
1627 Control display of debugging info for determining frame argument values at
1628 function entry and virtual tail call frames.
1630 set basenames-may-differ
1631 show basenames-may-differ
1632 Set whether a source file may have multiple base names.
1633 (A "base name" is the name of a file with the directory part removed.
1634 Example: The base name of "/home/user/hello.c" is "hello.c".)
1635 If set, GDB will canonicalize file names (e.g., expand symlinks)
1636 before comparing them. Canonicalization is an expensive operation,
1637 but it allows the same file be known by more than one base name.
1638 If not set (the default), all source files are assumed to have just
1639 one base name, and gdb will do file name comparisons more efficiently.
1645 Set a user name and notes for the current and any future trace runs.
1646 This is useful for long-running and/or disconnected traces, to
1647 inform others (or yourself) as to who is running the trace, supply
1648 contact information, or otherwise explain what is going on.
1650 set trace-stop-notes
1651 show trace-stop-notes
1652 Set a note attached to the trace run, that is displayed when the
1653 trace has been stopped by a tstop command. This is useful for
1654 instance as an explanation, if you are stopping a trace run that was
1655 started by someone else.
1657 * New remote packets
1661 Dynamically enable a tracepoint in a started trace experiment.
1665 Dynamically disable a tracepoint in a started trace experiment.
1669 Set the user and notes of the trace run.
1673 Query the current status of a tracepoint.
1677 Query the minimum length of instruction at which a fast tracepoint may
1680 * Dcache size (number of lines) and line-size are now runtime-configurable
1681 via "set dcache line" and "set dcache line-size" commands.
1685 Texas Instruments TMS320C6x tic6x-*-*
1689 Renesas RL78 rl78-*-elf
1691 *** Changes in GDB 7.3.1
1693 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1695 *** Changes in GDB 7.3
1697 * GDB has a new command: "thread find [REGEXP]".
1698 It finds the thread id whose name, target id, or thread extra info
1699 matches the given regular expression.
1701 * The "catch syscall" command now works on mips*-linux* targets.
1703 * The -data-disassemble MI command now supports modes 2 and 3 for
1704 dumping the instruction opcodes.
1706 * New command line options
1708 -data-directory DIR Specify DIR as the "data-directory".
1709 This is mostly for testing purposes.
1711 * The "maint set python auto-load on|off" command has been renamed to
1712 "set auto-load-scripts on|off".
1714 * GDB has a new command: "set directories".
1715 It is like the "dir" command except that it replaces the
1716 source path list instead of augmenting it.
1718 * GDB now understands thread names.
1720 On GNU/Linux, "info threads" will display the thread name as set by
1721 prctl or pthread_setname_np.
1723 There is also a new command, "thread name", which can be used to
1724 assign a name internally for GDB to display.
1727 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1728 has been integrated into GDB.
1732 ** The function gdb.Write now accepts an optional keyword 'stream'.
1733 This keyword, when provided, will direct the output to either
1734 stdout, stderr, or GDB's logging output.
1736 ** Parameters can now be be sub-classed in Python, and in particular
1737 you may implement the get_set_doc and get_show_doc functions.
1738 This improves how Parameter set/show documentation is processed
1739 and allows for more dynamic content.
1741 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1742 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1743 have an is_valid method.
1745 ** Breakpoints can now be sub-classed in Python, and in particular
1746 you may implement a 'stop' function that is executed each time
1747 the inferior reaches that breakpoint.
1749 ** New function gdb.lookup_global_symbol looks up a global symbol.
1751 ** GDB values in Python are now callable if the value represents a
1752 function. For example, if 'some_value' represents a function that
1753 takes two integer parameters and returns a value, you can call
1754 that function like so:
1756 result = some_value (10,20)
1758 ** Module gdb.types has been added.
1759 It contains a collection of utilities for working with gdb.Types objects:
1760 get_basic_type, has_field, make_enum_dict.
1762 ** Module gdb.printing has been added.
1763 It contains utilities for writing and registering pretty-printers.
1764 New classes: PrettyPrinter, SubPrettyPrinter,
1765 RegexpCollectionPrettyPrinter.
1766 New function: register_pretty_printer.
1768 ** New commands "info pretty-printers", "enable pretty-printer" and
1769 "disable pretty-printer" have been added.
1771 ** gdb.parameter("directories") is now available.
1773 ** New function gdb.newest_frame returns the newest frame in the
1776 ** The gdb.InferiorThread class has a new "name" attribute. This
1777 holds the thread's name.
1779 ** Python Support for Inferior events.
1780 Python scripts can add observers to be notified of events
1781 occurring in the process being debugged.
1782 The following events are currently supported:
1783 - gdb.events.cont Continue event.
1784 - gdb.events.exited Inferior exited event.
1785 - gdb.events.stop Signal received, and Breakpoint hit events.
1789 ** GDB now puts template parameters in scope when debugging in an
1790 instantiation. For example, if you have:
1792 template<int X> int func (void) { return X; }
1794 then if you step into func<5>, "print X" will show "5". This
1795 feature requires proper debuginfo support from the compiler; it
1796 was added to GCC 4.5.
1798 ** The motion commands "next", "finish", "until", and "advance" now
1799 work better when exceptions are thrown. In particular, GDB will
1800 no longer lose control of the inferior; instead, the GDB will
1801 stop the inferior at the point at which the exception is caught.
1802 This functionality requires a change in the exception handling
1803 code that was introduced in GCC 4.5.
1805 * GDB now follows GCC's rules on accessing volatile objects when
1806 reading or writing target state during expression evaluation.
1807 One notable difference to prior behavior is that "print x = 0"
1808 no longer generates a read of x; the value of the assignment is
1809 now always taken directly from the value being assigned.
1811 * GDB now has some support for using labels in the program's source in
1812 linespecs. For instance, you can use "advance label" to continue
1813 execution to a label.
1815 * GDB now has support for reading and writing a new .gdb_index
1816 section. This section holds a fast index of DWARF debugging
1817 information and can be used to greatly speed up GDB startup and
1818 operation. See the documentation for `save gdb-index' for details.
1820 * The "watch" command now accepts an optional "-location" argument.
1821 When used, this causes GDB to watch the memory referred to by the
1822 expression. Such a watchpoint is never deleted due to it going out
1825 * GDB now supports thread debugging of core dumps on GNU/Linux.
1827 GDB now activates thread debugging using the libthread_db library
1828 when debugging GNU/Linux core dumps, similarly to when debugging
1829 live processes. As a result, when debugging a core dump file, GDB
1830 is now able to display pthread_t ids of threads. For example, "info
1831 threads" shows the same output as when debugging the process when it
1832 was live. In earlier releases, you'd see something like this:
1835 * 1 LWP 6780 main () at main.c:10
1837 While now you see this:
1840 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1842 It is also now possible to inspect TLS variables when debugging core
1845 When debugging a core dump generated on a machine other than the one
1846 used to run GDB, you may need to point GDB at the correct
1847 libthread_db library with the "set libthread-db-search-path"
1848 command. See the user manual for more details on this command.
1850 * When natively debugging programs on PowerPC BookE processors running
1851 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1852 which stop execution of the inferior whenever it executes an instruction
1853 at any address within the specified range. See the "PowerPC Embedded"
1854 section in the user manual for more details.
1856 * New features in the GDB remote stub, GDBserver
1858 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1859 and i686 LynxOS (version 5.x).
1861 ** GDBserver is now supported on Blackfin Linux.
1863 * New native configurations
1865 ia64 HP-UX ia64-*-hpux*
1869 Analog Devices, Inc. Blackfin Processor bfin-*
1871 * Ada task switching is now supported on sparc-elf targets when
1872 debugging a program using the Ravenscar Profile. For more information,
1873 see the "Tasking Support when using the Ravenscar Profile" section
1874 in the GDB user manual.
1876 * Guile support was removed.
1878 * New features in the GNU simulator
1880 ** The --map-info flag lists all known core mappings.
1882 ** CFI flashes may be simulated via the "cfi" device.
1884 *** Changes in GDB 7.2
1886 * Shared library support for remote targets by default
1888 When GDB is configured for a generic, non-OS specific target, like
1889 for example, --target=arm-eabi or one of the many *-*-elf targets,
1890 GDB now queries remote stubs for loaded shared libraries using the
1891 `qXfer:libraries:read' packet. Previously, shared library support
1892 was always disabled for such configurations.
1896 ** Argument Dependent Lookup (ADL)
1898 In C++ ADL lookup directs function search to the namespaces of its
1899 arguments even if the namespace has not been imported.
1909 Here the compiler will search for `foo' in the namespace of 'b'
1910 and find A::foo. GDB now supports this. This construct is commonly
1911 used in the Standard Template Library for operators.
1913 ** Improved User Defined Operator Support
1915 In addition to member operators, GDB now supports lookup of operators
1916 defined in a namespace and imported with a `using' directive, operators
1917 defined in the global scope, operators imported implicitly from an
1918 anonymous namespace, and the ADL operators mentioned in the previous
1920 GDB now also supports proper overload resolution for all the previously
1921 mentioned flavors of operators.
1923 ** static const class members
1925 Printing of static const class members that are initialized in the
1926 class definition has been fixed.
1928 * Windows Thread Information Block access.
1930 On Windows targets, GDB now supports displaying the Windows Thread
1931 Information Block (TIB) structure. This structure is visible either
1932 by using the new command `info w32 thread-information-block' or, by
1933 dereferencing the new convenience variable named `$_tlb', a
1934 thread-specific pointer to the TIB. This feature is also supported
1935 when remote debugging using GDBserver.
1937 * Static tracepoints
1939 Static tracepoints are calls in the user program into a tracing
1940 library. One such library is a port of the LTTng kernel tracer to
1941 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1942 When debugging with GDBserver, GDB now supports combining the GDB
1943 tracepoint machinery with such libraries. For example: the user can
1944 use GDB to probe a static tracepoint marker (a call from the user
1945 program into the tracing library) with the new "strace" command (see
1946 "New commands" below). This creates a "static tracepoint" in the
1947 breakpoint list, that can be manipulated with the same feature set
1948 as fast and regular tracepoints. E.g., collect registers, local and
1949 global variables, collect trace state variables, and define
1950 tracepoint conditions. In addition, the user can collect extra
1951 static tracepoint marker specific data, by collecting the new
1952 $_sdata internal variable. When analyzing the trace buffer, you can
1953 inspect $_sdata like any other variable available to GDB. For more
1954 information, see the "Tracepoints" chapter in GDB user manual. New
1955 remote packets have been defined to support static tracepoints, see
1956 the "New remote packets" section below.
1958 * Better reconstruction of tracepoints after disconnected tracing
1960 GDB will attempt to download the original source form of tracepoint
1961 definitions when starting a trace run, and then will upload these
1962 upon reconnection to the target, resulting in a more accurate
1963 reconstruction of the tracepoints that are in use on the target.
1967 You can now exercise direct control over the ways that GDB can
1968 affect your program. For instance, you can disallow the setting of
1969 breakpoints, so that the program can run continuously (assuming
1970 non-stop mode). In addition, the "observer" variable is available
1971 to switch all of the different controls; in observer mode, GDB
1972 cannot affect the target's behavior at all, which is useful for
1973 tasks like diagnosing live systems in the field.
1975 * The new convenience variable $_thread holds the number of the
1978 * New remote packets
1982 Return the address of the Windows Thread Information Block of a given thread.
1986 In response to several of the tracepoint packets, the target may now
1987 also respond with a number of intermediate `qRelocInsn' request
1988 packets before the final result packet, to have GDB handle
1989 relocating an instruction to execute at a different address. This
1990 is particularly useful for stubs that support fast tracepoints. GDB
1991 reports support for this feature in the qSupported packet.
1995 List static tracepoint markers in the target program.
1999 List static tracepoint markers at a given address in the target
2002 qXfer:statictrace:read
2004 Read the static trace data collected (by a `collect $_sdata'
2005 tracepoint action). The remote stub reports support for this packet
2006 to gdb's qSupported query.
2010 Send the current settings of GDB's permission flags.
2014 Send part of the source (textual) form of a tracepoint definition,
2015 which includes location, conditional, and action list.
2017 * The source command now accepts a -s option to force searching for the
2018 script in the source search path even if the script name specifies
2021 * New features in the GDB remote stub, GDBserver
2023 - GDBserver now support tracepoints (including fast tracepoints, and
2024 static tracepoints). The feature is currently supported by the
2025 i386-linux and amd64-linux builds. See the "Tracepoints support
2026 in gdbserver" section in the manual for more information.
2028 GDBserver JIT compiles the tracepoint's conditional agent
2029 expression bytecode into native code whenever possible for low
2030 overhead dynamic tracepoints conditionals. For such tracepoints,
2031 an expression that examines program state is evaluated when the
2032 tracepoint is reached, in order to determine whether to capture
2033 trace data. If the condition is simple and false, processing the
2034 tracepoint finishes very quickly and no data is gathered.
2036 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2037 for static tracepoints support.
2039 - GDBserver now supports x86_64 Windows 64-bit debugging.
2041 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2042 it understands register description.
2044 * The --batch flag now disables pagination and queries.
2046 * X86 general purpose registers
2048 GDB now supports reading/writing byte, word and double-word x86
2049 general purpose registers directly. This means you can use, say,
2050 $ah or $ax to refer, respectively, to the byte register AH and
2051 16-bit word register AX that are actually portions of the 32-bit
2052 register EAX or 64-bit register RAX.
2054 * The `commands' command now accepts a range of breakpoints to modify.
2055 A plain `commands' following a command that creates multiple
2056 breakpoints affects all the breakpoints set by that command. This
2057 applies to breakpoints set by `rbreak', and also applies when a
2058 single `break' command creates multiple breakpoints (e.g.,
2059 breakpoints on overloaded c++ functions).
2061 * The `rbreak' command now accepts a filename specification as part of
2062 its argument, limiting the functions selected by the regex to those
2063 in the specified file.
2065 * Support for remote debugging Windows and SymbianOS shared libraries
2066 from Unix hosts has been improved. Non Windows GDB builds now can
2067 understand target reported file names that follow MS-DOS based file
2068 system semantics, such as file names that include drive letters and
2069 use the backslash character as directory separator. This makes it
2070 possible to transparently use the "set sysroot" and "set
2071 solib-search-path" on Unix hosts to point as host copies of the
2072 target's shared libraries. See the new command "set
2073 target-file-system-kind" described below, and the "Commands to
2074 specify files" section in the user manual for more information.
2078 eval template, expressions...
2079 Convert the values of one or more expressions under the control
2080 of the string template to a command line, and call it.
2082 set target-file-system-kind unix|dos-based|auto
2083 show target-file-system-kind
2084 Set or show the assumed file system kind for target reported file
2087 save breakpoints <filename>
2088 Save all current breakpoint definitions to a file suitable for use
2089 in a later debugging session. To read the saved breakpoint
2090 definitions, use the `source' command.
2092 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2095 info static-tracepoint-markers
2096 Display information about static tracepoint markers in the target.
2098 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2099 Define a static tracepoint by probing a marker at the given
2100 function, line, address, or marker ID.
2104 Enable and disable observer mode.
2106 set may-write-registers on|off
2107 set may-write-memory on|off
2108 set may-insert-breakpoints on|off
2109 set may-insert-tracepoints on|off
2110 set may-insert-fast-tracepoints on|off
2111 set may-interrupt on|off
2112 Set individual permissions for GDB effects on the target. Note that
2113 some of these settings can have undesirable or surprising
2114 consequences, particularly when changed in the middle of a session.
2115 For instance, disabling the writing of memory can prevent
2116 breakpoints from being inserted, cause single-stepping to fail, or
2117 even crash your program, if you disable after breakpoints have been
2118 inserted. However, GDB should not crash.
2120 set record memory-query on|off
2121 show record memory-query
2122 Control whether to stop the inferior if memory changes caused
2123 by an instruction cannot be recorded.
2128 The disassemble command now supports "start,+length" form of two arguments.
2132 ** GDB now provides a new directory location, called the python directory,
2133 where Python scripts written for GDB can be installed. The location
2134 of that directory is <data-directory>/python, where <data-directory>
2135 is the GDB data directory. For more details, see section `Scripting
2136 GDB using Python' in the manual.
2138 ** The GDB Python API now has access to breakpoints, symbols, symbol
2139 tables, program spaces, inferiors, threads and frame's code blocks.
2140 Additionally, GDB Parameters can now be created from the API, and
2141 manipulated via set/show in the CLI.
2143 ** New functions gdb.target_charset, gdb.target_wide_charset,
2144 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2146 ** New exception gdb.GdbError.
2148 ** Pretty-printers are now also looked up in the current program space.
2150 ** Pretty-printers can now be individually enabled and disabled.
2152 ** GDB now looks for names of Python scripts to auto-load in a
2153 special section named `.debug_gdb_scripts', in addition to looking
2154 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2156 * Tracepoint actions were unified with breakpoint commands. In particular,
2157 there are no longer differences in "info break" output for breakpoints and
2158 tracepoints and the "commands" command can be used for both tracepoints and
2159 regular breakpoints.
2163 ARM Symbian arm*-*-symbianelf*
2165 * D language support.
2166 GDB now supports debugging programs written in the D programming
2169 * GDB now supports the extended ptrace interface for PowerPC which is
2170 available since Linux kernel version 2.6.34. This automatically enables
2171 any hardware breakpoints and additional hardware watchpoints available in
2172 the processor. The old ptrace interface exposes just one hardware
2173 watchpoint and no hardware breakpoints.
2175 * GDB is now able to use the Data Value Compare (DVC) register available on
2176 embedded PowerPC processors to implement in hardware simple watchpoint
2177 conditions of the form:
2179 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2181 This works in native GDB running on Linux kernels with the extended ptrace
2182 interface mentioned above.
2184 *** Changes in GDB 7.1
2188 ** Namespace Support
2190 GDB now supports importing of namespaces in C++. This enables the
2191 user to inspect variables from imported namespaces. Support for
2192 namepace aliasing has also been added. So, if a namespace is
2193 aliased in the current scope (e.g. namepace C=A; ) the user can
2194 print variables using the alias (e.g. (gdb) print C::x).
2198 All known bugs relating to the printing of virtual base class were
2199 fixed. It is now possible to call overloaded static methods using a
2204 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2205 and reinterpret_cast<> are now handled by the C++ expression parser.
2209 Xilinx MicroBlaze microblaze-*-*
2214 Xilinx MicroBlaze microblaze
2217 * Multi-program debugging.
2219 GDB now has support for multi-program (a.k.a. multi-executable or
2220 multi-exec) debugging. This allows for debugging multiple inferiors
2221 simultaneously each running a different program under the same GDB
2222 session. See "Debugging Multiple Inferiors and Programs" in the
2223 manual for more information. This implied some user visible changes
2224 in the multi-inferior support. For example, "info inferiors" now
2225 lists inferiors that are not running yet or that have exited
2226 already. See also "New commands" and "New options" below.
2228 * New tracing features
2230 GDB's tracepoint facility now includes several new features:
2232 ** Trace state variables
2234 GDB tracepoints now include support for trace state variables, which
2235 are variables managed by the target agent during a tracing
2236 experiment. They are useful for tracepoints that trigger each
2237 other, so for instance one tracepoint can count hits in a variable,
2238 and then a second tracepoint has a condition that is true when the
2239 count reaches a particular value. Trace state variables share the
2240 $-syntax of GDB convenience variables, and can appear in both
2241 tracepoint actions and condition expressions. Use the "tvariable"
2242 command to create, and "info tvariables" to view; see "Trace State
2243 Variables" in the manual for more detail.
2247 GDB now includes an option for defining fast tracepoints, which
2248 targets may implement more efficiently, such as by installing a jump
2249 into the target agent rather than a trap instruction. The resulting
2250 speedup can be by two orders of magnitude or more, although the
2251 tradeoff is that some program locations on some target architectures
2252 might not allow fast tracepoint installation, for instance if the
2253 instruction to be replaced is shorter than the jump. To request a
2254 fast tracepoint, use the "ftrace" command, with syntax identical to
2255 the regular trace command.
2257 ** Disconnected tracing
2259 It is now possible to detach GDB from the target while it is running
2260 a trace experiment, then reconnect later to see how the experiment
2261 is going. In addition, a new variable disconnected-tracing lets you
2262 tell the target agent whether to continue running a trace if the
2263 connection is lost unexpectedly.
2267 GDB now has the ability to save the trace buffer into a file, and
2268 then use that file as a target, similarly to you can do with
2269 corefiles. You can select trace frames, print data that was
2270 collected in them, and use tstatus to display the state of the
2271 tracing run at the moment that it was saved. To create a trace
2272 file, use "tsave <filename>", and to use it, do "target tfile
2275 ** Circular trace buffer
2277 You can ask the target agent to handle the trace buffer as a
2278 circular buffer, discarding the oldest trace frames to make room for
2279 newer ones, by setting circular-trace-buffer to on. This feature may
2280 not be available for all target agents.
2285 The disassemble command, when invoked with two arguments, now requires
2286 the arguments to be comma-separated.
2289 The info variables command now displays variable definitions. Files
2290 which only declare a variable are not shown.
2293 The source command is now capable of sourcing Python scripts.
2294 This feature is dependent on the debugger being build with Python
2297 Related to this enhancement is also the introduction of a new command
2298 "set script-extension" (see below).
2300 * New commands (for set/show, see "New options" below)
2302 record save [<FILENAME>]
2303 Save a file (in core file format) containing the process record
2304 execution log for replay debugging at a later time.
2306 record restore <FILENAME>
2307 Restore the process record execution log that was saved at an
2308 earlier time, for replay debugging.
2310 add-inferior [-copies <N>] [-exec <FILENAME>]
2313 clone-inferior [-copies <N>] [ID]
2314 Make a new inferior ready to execute the same program another
2315 inferior has loaded.
2320 maint info program-spaces
2321 List the program spaces loaded into GDB.
2323 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2324 show remote interrupt-sequence
2325 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2326 as the sequence to the remote target in order to interrupt the execution.
2327 Ctrl-C is a default. Some system prefers BREAK which is high level of
2328 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2329 Magic SysRq g. It is BREAK signal and character 'g'.
2331 set remote interrupt-on-connect [on | off]
2332 show remote interrupt-on-connect
2333 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2334 remote target when gdb connects to it. This is needed when you debug
2337 set remotebreak [on | off]
2339 Deprecated. Use "set/show remote interrupt-sequence" instead.
2341 tvariable $NAME [ = EXP ]
2342 Create or modify a trace state variable.
2345 List trace state variables and their values.
2347 delete tvariable $NAME ...
2348 Delete one or more trace state variables.
2351 Evaluate the given expressions without collecting anything into the
2352 trace buffer. (Valid in tracepoint actions only.)
2354 ftrace FN / FILE:LINE / *ADDR
2355 Define a fast tracepoint at the given function, line, or address.
2357 * New expression syntax
2359 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2360 GDB now parses 0b101010 identically with 42.
2364 set follow-exec-mode new|same
2365 show follow-exec-mode
2366 Control whether GDB reuses the same inferior across an exec call or
2367 creates a new one. This is useful to be able to restart the old
2368 executable after the inferior having done an exec call.
2370 set default-collect EXPR, ...
2371 show default-collect
2372 Define a list of expressions to be collected at each tracepoint.
2373 This is a useful way to ensure essential items are not overlooked,
2374 such as registers or a critical global variable.
2376 set disconnected-tracing
2377 show disconnected-tracing
2378 If set to 1, the target is instructed to continue tracing if it
2379 loses its connection to GDB. If 0, the target is to stop tracing
2382 set circular-trace-buffer
2383 show circular-trace-buffer
2384 If set to on, the target is instructed to use a circular trace buffer
2385 and discard the oldest trace frames instead of stopping the trace due
2386 to a full trace buffer. If set to off, the trace stops when the buffer
2387 fills up. Some targets may not support this.
2389 set script-extension off|soft|strict
2390 show script-extension
2391 If set to "off", the debugger does not perform any script language
2392 recognition, and all sourced files are assumed to be GDB scripts.
2393 If set to "soft" (the default), files are sourced according to
2394 filename extension, falling back to GDB scripts if the first
2396 If set to "strict", files are sourced according to filename extension.
2398 set ada trust-PAD-over-XVS on|off
2399 show ada trust-PAD-over-XVS
2400 If off, activate a workaround against a bug in the debugging information
2401 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2402 the GCC sources for more information about the GNAT encoding and
2403 PAD types in particular). It is always safe to set this option to
2404 off, but this introduces a slight performance penalty. The default
2407 * Python API Improvements
2409 ** GDB provides the new class gdb.LazyString. This is useful in
2410 some pretty-printing cases. The new method gdb.Value.lazy_string
2411 provides a simple way to create objects of this type.
2413 ** The fields returned by gdb.Type.fields now have an
2414 `is_base_class' attribute.
2416 ** The new method gdb.Type.range returns the range of an array type.
2418 ** The new method gdb.parse_and_eval can be used to parse and
2419 evaluate an expression.
2421 * New remote packets
2424 Define a trace state variable.
2427 Get the current value of a trace state variable.
2430 Set desired tracing behavior upon disconnection.
2433 Set the trace buffer to be linear or circular.
2436 Get data about the tracepoints currently in use.
2440 Process record now works correctly with hardware watchpoints.
2442 Multiple bug fixes have been made to the mips-irix port, making it
2443 much more reliable. In particular:
2444 - Debugging threaded applications is now possible again. Previously,
2445 GDB would hang while starting the program, or while waiting for
2446 the program to stop at a breakpoint.
2447 - Attaching to a running process no longer hangs.
2448 - An error occurring while loading a core file has been fixed.
2449 - Changing the value of the PC register now works again. This fixes
2450 problems observed when using the "jump" command, or when calling
2451 a function from GDB, or even when assigning a new value to $pc.
2452 - With the "finish" and "return" commands, the return value for functions
2453 returning a small array is now correctly printed.
2454 - It is now possible to break on shared library code which gets executed
2455 during a shared library init phase (code executed while executing
2456 their .init section). Previously, the breakpoint would have no effect.
2457 - GDB is now able to backtrace through the signal handler for
2458 non-threaded programs.
2460 PIE (Position Independent Executable) programs debugging is now supported.
2461 This includes debugging execution of PIC (Position Independent Code) shared
2462 libraries although for that, it should be possible to run such libraries as an
2465 *** Changes in GDB 7.0
2467 * GDB now has an interface for JIT compilation. Applications that
2468 dynamically generate code can create symbol files in memory and register
2469 them with GDB. For users, the feature should work transparently, and
2470 for JIT developers, the interface is documented in the GDB manual in the
2471 "JIT Compilation Interface" chapter.
2473 * Tracepoints may now be conditional. The syntax is as for
2474 breakpoints; either an "if" clause appended to the "trace" command,
2475 or the "condition" command is available. GDB sends the condition to
2476 the target for evaluation using the same bytecode format as is used
2477 for tracepoint actions.
2479 * The disassemble command now supports: an optional /r modifier, print the
2480 raw instructions in hex as well as in symbolic form, and an optional /m
2481 modifier to print mixed source+assembly.
2483 * Process record and replay
2485 In a architecture environment that supports ``process record and
2486 replay'', ``process record and replay'' target can record a log of
2487 the process execution, and replay it with both forward and reverse
2490 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2491 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2492 set execution-direction {forward|reverse}, for targets that support
2495 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2496 feature is available with a native GDB running on kernel version
2499 * GDB now has support for multi-byte and wide character sets on the
2500 target. Strings whose character type is wchar_t, char16_t, or
2501 char32_t are now correctly printed. GDB supports wide- and unicode-
2502 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2503 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2504 `printf'. This feature requires iconv to work properly; if your
2505 system does not have a working iconv, GDB can use GNU libiconv. See
2506 the installation instructions for more information.
2508 * GDB now supports automatic retrieval of shared library files from
2509 remote targets. To use this feature, specify a system root that begins
2510 with the `remote:' prefix, either via the `set sysroot' command or via
2511 the `--with-sysroot' configure-time option.
2513 * "info sharedlibrary" now takes an optional regex of libraries to show,
2514 and it now reports if a shared library has no debugging information.
2516 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2517 now complete on file names.
2519 * When completing in expressions, gdb will attempt to limit
2520 completions to allowable structure or union fields, where appropriate.
2521 For instance, consider:
2523 # struct example { int f1; double f2; };
2524 # struct example variable;
2527 If the user types TAB at the end of this command line, the available
2528 completions will be "f1" and "f2".
2530 * Inlined functions are now supported. They show up in backtraces, and
2531 the "step", "next", and "finish" commands handle them automatically.
2533 * GDB now supports the token-splicing (##) and stringification (#)
2534 operators when expanding macros. It also supports variable-arity
2537 * GDB now supports inspecting extra signal information, exported by
2538 the new $_siginfo convenience variable. The feature is currently
2539 implemented on linux ARM, i386 and amd64.
2541 * GDB can now display the VFP floating point registers and NEON vector
2542 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2543 can provide these registers (requires Linux 2.6.30 or later). Remote
2544 and simulator targets may also provide them.
2546 * New remote packets
2549 Search memory for a sequence of bytes.
2552 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2553 operation over reliable transport links. Use of this packet is
2554 controlled by the `set remote noack-packet' command.
2557 Kill the process with the specified process ID. Use this in preference
2558 to `k' when multiprocess protocol extensions are supported.
2561 Obtains additional operating system information
2565 Read or write additional signal information.
2567 * Removed remote protocol undocumented extension
2569 An undocumented extension to the remote protocol's `S' stop reply
2570 packet that permited the stub to pass a process id was removed.
2571 Remote servers should use the `T' stop reply packet instead.
2573 * GDB now supports multiple function calling conventions according to the
2574 DWARF-2 DW_AT_calling_convention function attribute.
2576 * The SH target utilizes the aforementioned change to distinguish between gcc
2577 and Renesas calling convention. It also adds the new CLI commands
2578 `set/show sh calling-convention'.
2580 * GDB can now read compressed debug sections, as produced by GNU gold
2581 with the --compress-debug-sections=zlib flag.
2583 * 64-bit core files are now supported on AIX.
2585 * Thread switching is now supported on Tru64.
2587 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2588 which will be allocated using malloc later in program execution.
2590 * The qXfer:libraries:read remote procotol packet now allows passing a
2591 list of section offsets.
2593 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2594 conditions handling signals delivered during attach or thread creation
2595 have also been fixed.
2597 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2598 From the user's standpoint, all unqualified instances of True and False
2599 are treated as the standard definitions, regardless of context.
2601 * GDB now parses C++ symbol and type names more flexibly. For
2604 template<typename T> class C { };
2607 GDB will now correctly handle all of:
2609 ptype C<char const *>
2610 ptype C<char const*>
2611 ptype C<const char *>
2612 ptype C<const char*>
2614 * New features in the GDB remote stub, gdbserver
2616 - The "--wrapper" command-line argument tells gdbserver to use a
2617 wrapper program to launch programs for debugging.
2619 - On PowerPC and S/390 targets, it is now possible to use a single
2620 gdbserver executable to debug both 32-bit and 64-bit programs.
2621 (This requires gdbserver itself to be built as a 64-bit executable.)
2623 - gdbserver uses the new noack protocol mode for TCP connections to
2624 reduce communications latency, if also supported and enabled in GDB.
2626 - Support for the sparc64-linux-gnu target is now included in
2629 - The amd64-linux build of gdbserver now supports debugging both
2630 32-bit and 64-bit programs.
2632 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2633 now support hardware watchpoints, and will use them automatically
2638 GDB now has support for scripting using Python. Whether this is
2639 available is determined at configure time.
2641 New GDB commands can now be written in Python.
2643 * Ada tasking support
2645 Ada tasks can now be inspected in GDB. The following commands have
2649 Print the list of Ada tasks.
2651 Print detailed information about task number N.
2653 Print the task number of the current task.
2655 Switch the context of debugging to task number N.
2657 * Support for user-defined prefixed commands. The "define" command can
2658 add new commands to existing prefixes, e.g. "target".
2660 * Multi-inferior, multi-process debugging.
2662 GDB now has generalized support for multi-inferior debugging. See
2663 "Debugging Multiple Inferiors" in the manual for more information.
2664 Although availability still depends on target support, the command
2665 set is more uniform now. The GNU/Linux specific multi-forks support
2666 has been migrated to this new framework. This implied some user
2667 visible changes; see "New commands" and also "Removed commands"
2670 * Target descriptions can now describe the target OS ABI. See the
2671 "Target Description Format" section in the user manual for more
2674 * Target descriptions can now describe "compatible" architectures
2675 to indicate that the target can execute applications for a different
2676 architecture in addition to those for the main target architecture.
2677 See the "Target Description Format" section in the user manual for
2680 * Multi-architecture debugging.
2682 GDB now includes general supports for debugging applications on
2683 hybrid systems that use more than one single processor architecture
2684 at the same time. Each such hybrid architecture still requires
2685 specific support to be added. The only hybrid architecture supported
2686 in this version of GDB is the Cell Broadband Engine.
2688 * GDB now supports integrated debugging of Cell/B.E. applications that
2689 use both the PPU and SPU architectures. To enable support for hybrid
2690 Cell/B.E. debugging, you need to configure GDB to support both the
2691 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2692 --enable-targets configure option.
2694 * Non-stop mode debugging.
2696 For some targets, GDB now supports an optional mode of operation in
2697 which you can examine stopped threads while other threads continue
2698 to execute freely. This is referred to as non-stop mode, with the
2699 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2700 section in the user manual for more information.
2702 To be able to support remote non-stop debugging, a remote stub needs
2703 to implement the non-stop mode remote protocol extensions, as
2704 described in the "Remote Non-Stop" section of the user manual. The
2705 GDB remote stub, gdbserver, has been adjusted to support these
2706 extensions on linux targets.
2708 * New commands (for set/show, see "New options" below)
2710 catch syscall [NAME(S) | NUMBER(S)]
2711 Catch system calls. Arguments, which should be names of system
2712 calls or their numbers, mean catch only those syscalls. Without
2713 arguments, every syscall will be caught. When the inferior issues
2714 any of the specified syscalls, GDB will stop and announce the system
2715 call, both when it is called and when its call returns. This
2716 feature is currently available with a native GDB running on the
2717 Linux Kernel, under the following architectures: x86, x86_64,
2718 PowerPC and PowerPC64.
2720 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2722 Search memory for a sequence of bytes.
2724 maint set python print-stack
2725 maint show python print-stack
2726 Show a stack trace when an error is encountered in a Python script.
2729 Invoke CODE by passing it to the Python interpreter.
2734 These allow macros to be defined, undefined, and listed
2738 Show operating system information about processes.
2741 List the inferiors currently under GDB's control.
2744 Switch focus to inferior number NUM.
2747 Detach from inferior number NUM.
2750 Kill inferior number NUM.
2754 set spu stop-on-load
2755 show spu stop-on-load
2756 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2758 set spu auto-flush-cache
2759 show spu auto-flush-cache
2760 Control whether to automatically flush the software-managed cache
2761 during Cell/B.E. debugging.
2763 set sh calling-convention
2764 show sh calling-convention
2765 Control the calling convention used when calling SH target functions.
2768 show debug timestamp
2769 Control display of timestamps with GDB debugging output.
2771 set disassemble-next-line
2772 show disassemble-next-line
2773 Control display of disassembled source lines or instructions when
2776 set remote noack-packet
2777 show remote noack-packet
2778 Set/show the use of remote protocol QStartNoAckMode packet. See above
2779 under "New remote packets."
2781 set remote query-attached-packet
2782 show remote query-attached-packet
2783 Control use of remote protocol `qAttached' (query-attached) packet.
2785 set remote read-siginfo-object
2786 show remote read-siginfo-object
2787 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2790 set remote write-siginfo-object
2791 show remote write-siginfo-object
2792 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2795 set remote reverse-continue
2796 show remote reverse-continue
2797 Control use of remote protocol 'bc' (reverse-continue) packet.
2799 set remote reverse-step
2800 show remote reverse-step
2801 Control use of remote protocol 'bs' (reverse-step) packet.
2803 set displaced-stepping
2804 show displaced-stepping
2805 Control displaced stepping mode. Displaced stepping is a way to
2806 single-step over breakpoints without removing them from the debuggee.
2807 Also known as "out-of-line single-stepping".
2810 show debug displaced
2811 Control display of debugging info for displaced stepping.
2813 maint set internal-error
2814 maint show internal-error
2815 Control what GDB does when an internal error is detected.
2817 maint set internal-warning
2818 maint show internal-warning
2819 Control what GDB does when an internal warning is detected.
2824 Use a wrapper program to launch programs for debugging.
2826 set multiple-symbols (all|ask|cancel)
2827 show multiple-symbols
2828 The value of this variable can be changed to adjust the debugger behavior
2829 when an expression or a breakpoint location contains an ambiguous symbol
2830 name (an overloaded function name, for instance).
2832 set breakpoint always-inserted
2833 show breakpoint always-inserted
2834 Keep breakpoints always inserted in the target, as opposed to inserting
2835 them when resuming the target, and removing them when the target stops.
2836 This option can improve debugger performance on slow remote targets.
2838 set arm fallback-mode (arm|thumb|auto)
2839 show arm fallback-mode
2840 set arm force-mode (arm|thumb|auto)
2842 These commands control how ARM GDB determines whether instructions
2843 are ARM or Thumb. The default for both settings is auto, which uses
2844 the current CPSR value for instructions without symbols; previous
2845 versions of GDB behaved as if "set arm fallback-mode arm".
2847 set disable-randomization
2848 show disable-randomization
2849 Standalone programs run with the virtual address space randomization enabled
2850 by default on some platforms. This option keeps the addresses stable across
2851 multiple debugging sessions.
2855 Control whether other threads are stopped or not when some thread hits
2860 Requests that asynchronous execution is enabled in the target, if available.
2861 In this case, it's possible to resume target in the background, and interact
2862 with GDB while the target is running. "show target-async" displays the
2863 current state of asynchronous execution of the target.
2865 set target-wide-charset
2866 show target-wide-charset
2867 The target-wide-charset is the name of the character set that GDB
2868 uses when printing characters whose type is wchar_t.
2870 set tcp auto-retry (on|off)
2872 set tcp connect-timeout
2873 show tcp connect-timeout
2874 These commands allow GDB to retry failed TCP connections to a remote stub
2875 with a specified timeout period; this is useful if the stub is launched
2876 in parallel with GDB but may not be ready to accept connections immediately.
2878 set libthread-db-search-path
2879 show libthread-db-search-path
2880 Control list of directories which GDB will search for appropriate
2883 set schedule-multiple (on|off)
2884 show schedule-multiple
2885 Allow GDB to resume all threads of all processes or only threads of
2886 the current process.
2890 Use more aggressive caching for accesses to the stack. This improves
2891 performance of remote debugging (particularly backtraces) without
2892 affecting correctness.
2894 set interactive-mode (on|off|auto)
2895 show interactive-mode
2896 Control whether GDB runs in interactive mode (on) or not (off).
2897 When in interactive mode, GDB waits for the user to answer all
2898 queries. Otherwise, GDB does not wait and assumes the default
2899 answer. When set to auto (the default), GDB determines which
2900 mode to use based on the stdin settings.
2905 For program forks, this is replaced by the new more generic `info
2906 inferiors' command. To list checkpoints, you can still use the
2907 `info checkpoints' command, which was an alias for the `info forks'
2911 Replaced by the new `inferior' command. To switch between
2912 checkpoints, you can still use the `restart' command, which was an
2913 alias for the `fork' command.
2916 This is removed, since some targets don't have a notion of
2917 processes. To switch between processes, you can still use the
2918 `inferior' command using GDB's own inferior number.
2921 For program forks, this is replaced by the new more generic `kill
2922 inferior' command. To delete a checkpoint, you can still use the
2923 `delete checkpoint' command, which was an alias for the `delete
2927 For program forks, this is replaced by the new more generic `detach
2928 inferior' command. To detach a checkpoint, you can still use the
2929 `detach checkpoint' command, which was an alias for the `detach
2932 * New native configurations
2934 x86/x86_64 Darwin i[34567]86-*-darwin*
2936 x86_64 MinGW x86_64-*-mingw*
2940 Lattice Mico32 lm32-*
2941 x86 DICOS i[34567]86-*-dicos*
2942 x86_64 DICOS x86_64-*-dicos*
2945 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2946 (mingw32ce) debugging.
2952 These commands were actually not implemented on any target.
2954 *** Changes in GDB 6.8
2956 * New native configurations
2958 NetBSD/hppa hppa*-*netbsd*
2959 Xtensa GNU/Linux xtensa*-*-linux*
2963 NetBSD/hppa hppa*-*-netbsd*
2964 Xtensa GNU/Lunux xtensa*-*-linux*
2966 * Change in command line behavior -- corefiles vs. process ids.
2968 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2969 attaching to process NUMBER fails, GDB no longer attempts to open a
2970 core file named NUMBER. Attaching to a program using the -c option
2971 is no longer supported. Instead, use the '-p' or '--pid' options.
2973 * GDB can now be built as a native debugger for debugging Windows x86
2974 (mingw32) Portable Executable (PE) programs.
2976 * Pending breakpoints no longer change their number when their address
2979 * GDB now supports breakpoints with multiple locations,
2980 including breakpoints on C++ constructors, inside C++ templates,
2981 and in inlined functions.
2983 * GDB's ability to debug optimized code has been improved. GDB more
2984 accurately identifies function bodies and lexical blocks that occupy
2985 more than one contiguous range of addresses.
2987 * Target descriptions can now describe registers for PowerPC.
2989 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2990 registers on PowerPC targets.
2992 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2993 targets even when the libthread_db library is not available.
2995 * The GDB remote stub, gdbserver, now supports the new file transfer
2996 commands (remote put, remote get, and remote delete).
2998 * The GDB remote stub, gdbserver, now supports run and attach in
2999 extended-remote mode.
3001 * hppa*64*-*-hpux11* target broken
3002 The debugger is unable to start a program and fails with the following
3003 error: "Error trying to get information about dynamic linker".
3004 The gdb-6.7 release is also affected.
3006 * GDB now supports the --enable-targets= configure option to allow
3007 building a single GDB executable that supports multiple remote
3008 target architectures.
3010 * GDB now supports debugging C and C++ programs which use the
3011 Decimal Floating Point extension. In addition, the PowerPC target
3012 now has a set of pseudo-registers to inspect decimal float values
3013 stored in two consecutive float registers.
3015 * The -break-insert MI command can optionally create pending
3018 * Improved support for debugging Ada
3019 Many improvements to the Ada language support have been made. These
3021 - Better support for Ada2005 interface types
3022 - Improved handling of arrays and slices in general
3023 - Better support for Taft-amendment types
3024 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3026 - Improved command completion in Ada
3029 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3034 set print frame-arguments (all|scalars|none)
3035 show print frame-arguments
3036 The value of this variable can be changed to control which argument
3037 values should be printed by the debugger when displaying a frame.
3042 Transfer files to and from a remote target, and delete remote files.
3049 Transfer files to and from a remote target, and delete remote files.
3051 * New remote packets
3058 Open, close, read, write, and delete files on the remote system.
3061 Attach to an existing process on the remote system, in extended-remote
3065 Run a new process on the remote system, in extended-remote mode.
3067 *** Changes in GDB 6.7
3069 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3070 bfd, libiberty and opcodes, as revealed by static analysis donated by
3071 Coverity, Inc. (http://scan.coverity.com).
3073 * When looking up multiply-defined global symbols, GDB will now prefer the
3074 symbol definition in the current shared library if it was built using the
3075 -Bsymbolic linker option.
3077 * When the Text User Interface (TUI) is not configured, GDB will now
3078 recognize the -tui command-line option and print a message that the TUI
3081 * The GDB remote stub, gdbserver, now has lower overhead for high
3082 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3084 * GDB for MIPS targets now autodetects whether a remote target provides
3085 32-bit or 64-bit register values.
3087 * Support for C++ member pointers has been improved.
3089 * GDB now understands XML target descriptions, which specify the
3090 target's overall architecture. GDB can read a description from
3091 a local file or over the remote serial protocol.
3093 * Vectors of single-byte data use a new integer type which is not
3094 automatically displayed as character or string data.
3096 * The /s format now works with the print command. It displays
3097 arrays of single-byte integers and pointers to single-byte integers
3100 * Target descriptions can now describe target-specific registers,
3101 for architectures which have implemented the support (currently
3102 only ARM, M68K, and MIPS).
3104 * GDB and the GDB remote stub, gdbserver, now support the XScale
3107 * The GDB remote stub, gdbserver, has been updated to support
3108 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3109 has been rewritten to use the standard GDB remote protocol.
3111 * GDB can now step into C++ functions which are called through thunks.
3113 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3115 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3116 layout. It also supports a TextSeg= and DataSeg= response when only
3117 segment base addresses (rather than offsets) are available.
3119 * The /i format now outputs any trailing branch delay slot instructions
3120 immediately following the last instruction within the count specified.
3122 * The GDB remote protocol "T" stop reply packet now supports a
3123 "library" response. Combined with the new "qXfer:libraries:read"
3124 packet, this response allows GDB to debug shared libraries on targets
3125 where the operating system manages the list of loaded libraries (e.g.
3126 Windows and SymbianOS).
3128 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3129 (DLLs) on Windows and Windows CE targets.
3131 * GDB now supports a faster verification that a .debug file matches its binary
3132 according to its build-id signature, if the signature is present.
3138 Enable or disable hardware flow control (RTS/CTS) on the serial port
3139 when debugging using remote targets.
3141 set mem inaccessible-by-default
3142 show mem inaccessible-by-default
3143 If the target supplies a memory map, for instance via the remote
3144 protocol's "qXfer:memory-map:read" packet, setting this variable
3145 prevents GDB from accessing memory outside the memory map. This
3146 is useful for targets with memory mapped registers or which react
3147 badly to accesses of unmapped address space.
3149 set breakpoint auto-hw
3150 show breakpoint auto-hw
3151 If the target supplies a memory map, for instance via the remote
3152 protocol's "qXfer:memory-map:read" packet, setting this variable
3153 lets GDB use hardware breakpoints automatically for memory regions
3154 where it can not use software breakpoints. This covers both the
3155 "break" command and internal breakpoints used for other commands
3156 including "next" and "finish".
3159 catch exception unhandled
3160 Stop the program execution when Ada exceptions are raised.
3163 Stop the program execution when an Ada assertion failed.
3167 Set an alternate system root for target files. This is a more
3168 general version of "set solib-absolute-prefix", which is now
3169 an alias to "set sysroot".
3172 Provide extended SPU facility status information. This set of
3173 commands is available only when debugging the Cell/B.E. SPU
3176 * New native configurations
3178 OpenBSD/sh sh*-*openbsd*
3181 unset tdesc filename
3183 Use the specified local file as an XML target description, and do
3184 not query the target for its built-in description.
3188 OpenBSD/sh sh*-*-openbsd*
3189 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3190 Toshiba Media Processor mep-elf
3192 * New remote packets
3195 Ignore the specified signals; pass them directly to the debugged program
3196 without stopping other threads or reporting them to GDB.
3198 qXfer:features:read:
3199 Read an XML target description from the target, which describes its
3204 Read or write contents of an spufs file on the target system. These
3205 packets are available only on the Cell/B.E. SPU architecture.
3207 qXfer:libraries:read:
3208 Report the loaded shared libraries. Combined with new "T" packet
3209 response, this packet allows GDB to debug shared libraries on
3210 targets where the operating system manages the list of loaded
3211 libraries (e.g. Windows and SymbianOS).
3215 Support for these obsolete configurations has been removed.
3223 i[34567]86-*-lynxos*
3224 i[34567]86-*-netware*
3225 i[34567]86-*-sco3.2v5*
3226 i[34567]86-*-sco3.2v4*
3228 i[34567]86-*-sysv4.2*
3231 i[34567]86-*-unixware2*
3232 i[34567]86-*-unixware*
3241 * Other removed features
3248 Various m68k-only ROM monitors.
3255 Various Renesas ROM monitors and debugging interfaces for SH and
3260 Support for a Macraigor serial interface to on-chip debugging.
3261 GDB does not directly support the newer parallel or USB
3266 A debug information format. The predecessor to DWARF 2 and
3267 DWARF 3, which are still supported.
3269 Support for the HP aCC compiler on HP-UX/PA-RISC
3271 SOM-encapsulated symbolic debugging information, automatic
3272 invocation of pxdb, and the aCC custom C++ ABI. This does not
3273 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3274 with aCC can still be debugged on an assembly level.
3276 MIPS ".pdr" sections
3278 A MIPS-specific format used to describe stack frame layout
3279 in debugging information.
3283 GDB could work with an older version of Guile to debug
3284 the interpreter and Scheme programs running in it.
3286 set mips stack-arg-size
3287 set mips saved-gpreg-size
3289 Use "set mips abi" to control parameter passing for MIPS.
3291 *** Changes in GDB 6.6
3296 Cell Broadband Engine SPU spu-elf
3298 * GDB can now be configured as a cross-debugger targeting native Windows
3299 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3300 running on a Windows system over TCP/IP to debug Windows programs.
3302 * The GDB remote stub, gdbserver, has been updated to support Windows and
3303 Cygwin debugging. Both single-threaded and multi-threaded programs are
3306 * The "set trust-readonly-sections" command works again. This command was
3307 broken in GDB 6.3, 6.4, and 6.5.
3309 * The "load" command now supports writing to flash memory, if the remote
3310 stub provides the required support.
3312 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3313 longer requires symbolic debug information (e.g. DWARF-2).
3318 unset substitute-path
3319 show substitute-path
3320 Manage a list of substitution rules that GDB uses to rewrite the name
3321 of the directories where the sources are located. This can be useful
3322 for instance when the sources were moved to a different location
3323 between compilation and debugging.
3327 Print each CLI command as it is executed. Each command is prefixed with
3328 a number of `+' symbols representing the nesting depth.
3329 The source command now has a `-v' option to enable the same feature.
3333 The ARM Demon monitor support (RDP protocol, "target rdp").
3335 Kernel Object Display, an embedded debugging feature which only worked with
3336 an obsolete version of Cisco IOS.
3338 The 'set download-write-size' and 'show download-write-size' commands.
3340 * New remote packets
3343 Tell a stub about GDB client features, and request remote target features.
3344 The first feature implemented is PacketSize, which allows the target to
3345 specify the size of packets it can handle - to minimize the number of
3346 packets required and improve performance when connected to a remote
3350 Fetch an OS auxilliary vector from the remote stub. This packet is a
3351 more efficient replacement for qPart:auxv:read.
3353 qXfer:memory-map:read:
3354 Fetch a memory map from the remote stub, including information about
3355 RAM, ROM, and flash memory devices.
3360 Erase and program a flash memory device.
3362 * Removed remote packets
3365 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3366 used it, and only gdbserver implemented it.
3368 *** Changes in GDB 6.5
3372 Renesas M32C/M16C m32c-elf
3374 Morpho Technologies ms1 ms1-elf
3378 init-if-undefined Initialize a convenience variable, but
3379 only if it doesn't already have a value.
3381 The following commands are presently only implemented for native GNU/Linux:
3383 checkpoint Save a snapshot of the program state.
3385 restart <n> Return the program state to a
3386 previously saved state.
3388 info checkpoints List currently saved checkpoints.
3390 delete-checkpoint <n> Delete a previously saved checkpoint.
3392 set|show detach-on-fork Tell gdb whether to detach from a newly
3393 forked process, or to keep debugging it.
3395 info forks List forks of the user program that
3396 are available to be debugged.
3398 fork <n> Switch to debugging one of several
3399 forks of the user program that are
3400 available to be debugged.
3402 delete-fork <n> Delete a fork from the list of forks
3403 that are available to be debugged (and
3404 kill the forked process).
3406 detach-fork <n> Delete a fork from the list of forks
3407 that are available to be debugged (and
3408 allow the process to continue).
3412 Morpho Technologies ms2 ms1-elf
3414 * Improved Windows host support
3416 GDB now builds as a cross debugger hosted on i686-mingw32, including
3417 native console support, and remote communications using either
3418 network sockets or serial ports.
3420 * Improved Modula-2 language support
3422 GDB can now print most types in the Modula-2 syntax. This includes:
3423 basic types, set types, record types, enumerated types, range types,
3424 pointer types and ARRAY types. Procedure var parameters are correctly
3425 printed and hexadecimal addresses and character constants are also
3426 written in the Modula-2 syntax. Best results can be obtained by using
3427 GNU Modula-2 together with the -gdwarf-2 command line option.
3431 The ARM rdi-share module.
3433 The Netware NLM debug server.
3435 *** Changes in GDB 6.4
3437 * New native configurations
3439 OpenBSD/arm arm*-*-openbsd*
3440 OpenBSD/mips64 mips64-*-openbsd*
3444 Morpho Technologies ms1 ms1-elf
3446 * New command line options
3448 --batch-silent As for --batch, but totally silent.
3449 --return-child-result The debugger will exist with the same value
3450 the child (debugged) program exited with.
3451 --eval-command COMMAND, -ex COMMAND
3452 Execute a single GDB CLI command. This may be
3453 specified multiple times and in conjunction
3454 with the --command (-x) option.
3456 * Deprecated commands removed
3458 The following commands, that were deprecated in 2000, have been
3462 set|show arm disassembly-flavor set|show arm disassembler
3463 othernames set arm disassembler
3464 set|show remotedebug set|show debug remote
3465 set|show archdebug set|show debug arch
3466 set|show eventdebug set|show debug event
3469 * New BSD user-level threads support
3471 It is now possible to debug programs using the user-level threads
3472 library on OpenBSD and FreeBSD. Currently supported (target)
3475 FreeBSD/amd64 x86_64-*-freebsd*
3476 FreeBSD/i386 i386-*-freebsd*
3477 OpenBSD/i386 i386-*-openbsd*
3479 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3480 are not yet supported.
3482 * New support for Matsushita MN10300 w/sim added
3483 (Work in progress). mn10300-elf.
3485 * REMOVED configurations and files
3487 VxWorks and the XDR protocol *-*-vxworks
3488 Motorola MCORE mcore-*-*
3489 National Semiconductor NS32000 ns32k-*-*
3491 * New "set print array-indexes" command
3493 After turning this setting "on", GDB prints the index of each element
3494 when displaying arrays. The default is "off" to preserve the previous
3497 * VAX floating point support
3499 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3501 * User-defined command support
3503 In addition to using $arg0..$arg9 for argument passing, it is now possible
3504 to use $argc to determine now many arguments have been passed. See the
3505 section on user-defined commands in the user manual for more information.
3507 *** Changes in GDB 6.3:
3509 * New command line option
3511 GDB now accepts -l followed by a number to set the timeout for remote
3514 * GDB works with GCC -feliminate-dwarf2-dups
3516 GDB now supports a more compact representation of DWARF-2 debug
3517 information using DW_FORM_ref_addr references. These are produced
3518 by GCC with the option -feliminate-dwarf2-dups and also by some
3519 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3520 to use -feliminate-dwarf2-dups.
3522 * Internationalization
3524 When supported by the host system, GDB will be built with
3525 internationalization (libintl). The task of marking up the sources is
3526 continued, we're looking forward to our first translation.
3530 Initial support for debugging programs compiled with the GNAT
3531 implementation of the Ada programming language has been integrated
3532 into GDB. In this release, support is limited to expression evaluation.
3534 * New native configurations
3536 GNU/Linux/m32r m32r-*-linux-gnu
3540 GDB's remote protocol now includes support for the 'p' packet. This
3541 packet is used to fetch individual registers from a remote inferior.
3543 * END-OF-LIFE registers[] compatibility module
3545 GDB's internal register infrastructure has been completely rewritten.
3546 The new infrastructure making possible the implementation of key new
3547 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3550 GDB 6.3 will be the last release to include the the registers[]
3551 compatibility module that allowed out-of-date configurations to
3552 continue to work. This change directly impacts the following
3562 powerpc bdm protocol
3564 Unless there is activity to revive these configurations, they will be
3565 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3567 * OBSOLETE configurations and files
3569 Configurations that have been declared obsolete in this release have
3570 been commented out. Unless there is activity to revive these
3571 configurations, the next release of GDB will have their sources
3572 permanently REMOVED.
3581 *** Changes in GDB 6.2.1:
3583 * MIPS `break main; run' gave an heuristic-fence-post warning
3585 When attempting to run even a simple program, a warning about
3586 heuristic-fence-post being hit would be reported. This problem has
3589 * MIPS IRIX 'long double' crashed GDB
3591 When examining a long double variable, GDB would get a segmentation
3592 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3593 IRIX long double values).
3597 A bug in the VAX stack code was causing problems with the "next"
3598 command. This problem has been fixed.
3600 *** Changes in GDB 6.2:
3602 * Fix for ``many threads''
3604 On GNU/Linux systems that use the NPTL threads library, a program
3605 rapidly creating and deleting threads would confuse GDB leading to the
3608 ptrace: No such process.
3609 thread_db_get_info: cannot get thread info: generic error
3611 This problem has been fixed.
3613 * "-async" and "-noasync" options removed.
3615 Support for the broken "-noasync" option has been removed (it caused
3618 * New ``start'' command.
3620 This command runs the program until the begining of the main procedure.
3622 * New BSD Kernel Data Access Library (libkvm) interface
3624 Using ``target kvm'' it is now possible to debug kernel core dumps and
3625 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3626 platforms. Currently supported (native-only) configurations are:
3628 FreeBSD/amd64 x86_64-*-freebsd*
3629 FreeBSD/i386 i?86-*-freebsd*
3630 NetBSD/i386 i?86-*-netbsd*
3631 NetBSD/m68k m68*-*-netbsd*
3632 NetBSD/sparc sparc-*-netbsd*
3633 OpenBSD/amd64 x86_64-*-openbsd*
3634 OpenBSD/i386 i?86-*-openbsd*
3635 OpenBSD/m68k m68*-openbsd*
3636 OpenBSD/sparc sparc-*-openbsd*
3638 * Signal trampoline code overhauled
3640 Many generic problems with GDB's signal handling code have been fixed.
3641 These include: backtraces through non-contiguous stacks; recognition
3642 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3643 call; backtrace through a signal trampoline; step into and out of
3644 signal handlers; and single-stepping in the signal trampoline.
3646 Please note that kernel bugs are a limiting factor here. These
3647 features have been shown to work on an s390 GNU/Linux system that
3648 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3650 * Cygwin support for DWARF 2 added.
3652 * New native configurations
3654 GNU/Linux/hppa hppa*-*-linux*
3655 OpenBSD/hppa hppa*-*-openbsd*
3656 OpenBSD/m68k m68*-*-openbsd*
3657 OpenBSD/m88k m88*-*-openbsd*
3658 OpenBSD/powerpc powerpc-*-openbsd*
3659 NetBSD/vax vax-*-netbsd*
3660 OpenBSD/vax vax-*-openbsd*
3662 * END-OF-LIFE frame compatibility module
3664 GDB's internal frame infrastructure has been completely rewritten.
3665 The new infrastructure making it possible to support key new features
3666 including DWARF 2 Call Frame Information. To aid in the task of
3667 migrating old configurations to this new infrastructure, a
3668 compatibility module, that allowed old configurations to continue to
3669 work, was also included.
3671 GDB 6.2 will be the last release to include this frame compatibility
3672 module. This change directly impacts the following configurations:
3682 Unless there is activity to revive these configurations, they will be
3683 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3685 * REMOVED configurations and files
3687 Sun 3, running SunOS 3 m68*-*-sunos3*
3688 Sun 3, running SunOS 4 m68*-*-sunos4*
3689 Sun 2, running SunOS 3 m68000-*-sunos3*
3690 Sun 2, running SunOS 4 m68000-*-sunos4*
3691 Motorola 680x0 running LynxOS m68*-*-lynxos*
3692 AT&T 3b1/Unix pc m68*-att-*
3693 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3694 decstation mips-dec-* mips-little-*
3695 riscos mips-*-riscos* mips-*-sysv*
3696 sonymips mips-sony-*
3697 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3699 *** Changes in GDB 6.1.1:
3701 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3703 The TUI (Text-mode User Interface) is now built as part of a default
3704 GDB configuration. It is enabled by either selecting the TUI with the
3705 command line option "-i=tui" or by running the separate "gdbtui"
3706 program. For more information on the TUI, see the manual "Debugging
3709 * Pending breakpoint support (also included in GDB 6.1)
3711 Support has been added to allow you to specify breakpoints in shared
3712 libraries that have not yet been loaded. If a breakpoint location
3713 cannot be found, and the "breakpoint pending" option is set to auto,
3714 GDB queries you if you wish to make the breakpoint pending on a future
3715 shared-library load. If and when GDB resolves the breakpoint symbol,
3716 the pending breakpoint is removed as one or more regular breakpoints
3719 Pending breakpoints are very useful for GCJ Java debugging.
3721 * Fixed ISO-C build problems
3723 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3724 non ISO-C code that stopped them being built using a more strict ISO-C
3725 compiler (e.g., IBM's C compiler).
3727 * Fixed build problem on IRIX 5
3729 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3730 wasn't able to compile compile on an IRIX 5 system.
3732 * Added execute permission to gdb/gdbserver/configure
3734 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3735 permission. This bug would cause configure to fail on a number of
3736 systems (Solaris, IRIX). Ref: server/519.
3738 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3740 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3741 has been updated to use constant array sizes.
3743 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3745 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3746 its generated DWARF Call Frame Info. This encoding was causing GDB to
3747 panic, that panic has been fixed. Ref: gdb/1628.
3749 * Fixed a problem when examining parameters in shared library code.
3751 When examining parameters in optimized shared library code generated
3752 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3753 not available''. GDB now correctly displays the variable's value.
3755 *** Changes in GDB 6.1:
3757 * Removed --with-mmalloc
3759 Support for the mmalloc memory manager has been removed, as it
3760 conflicted with the internal gdb byte cache.
3762 * Changes in AMD64 configurations
3764 The AMD64 target now includes the %cs and %ss registers. As a result
3765 the AMD64 remote protocol has changed; this affects the floating-point
3766 and SSE registers. If you rely on those registers for your debugging,
3767 you should upgrade gdbserver on the remote side.
3769 * Revised SPARC target
3771 The SPARC target has been completely revised, incorporating the
3772 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3773 support for LynxOS and SunOS 4 has been dropped. Calling functions
3774 from within GDB on operating systems with a non-executable stack
3775 (Solaris, OpenBSD) now works.
3779 GDB has a new C++ demangler which does a better job on the mangled
3780 names generated by current versions of g++. It also runs faster, so
3781 with this and other changes gdb should now start faster on large C++
3784 * DWARF 2 Location Expressions
3786 GDB support for location expressions has been extended to support function
3787 arguments and frame bases. Older versions of GDB could crash when they
3790 * C++ nested types and namespaces
3792 GDB's support for nested types and namespaces in C++ has been
3793 improved, especially if you use the DWARF 2 debugging format. (This
3794 is the default for recent versions of GCC on most platforms.)
3795 Specifically, if you have a class "Inner" defined within a class or
3796 namespace "Outer", then GDB realizes that the class's name is
3797 "Outer::Inner", not simply "Inner". This should greatly reduce the
3798 frequency of complaints about not finding RTTI symbols. In addition,
3799 if you are stopped at inside of a function defined within a namespace,
3800 GDB modifies its name lookup accordingly.
3802 * New native configurations
3804 NetBSD/amd64 x86_64-*-netbsd*
3805 OpenBSD/amd64 x86_64-*-openbsd*
3806 OpenBSD/alpha alpha*-*-openbsd*
3807 OpenBSD/sparc sparc-*-openbsd*
3808 OpenBSD/sparc64 sparc64-*-openbsd*
3810 * New debugging protocols
3812 M32R with SDI protocol m32r-*-elf*
3814 * "set prompt-escape-char" command deleted.
3816 The command "set prompt-escape-char" has been deleted. This command,
3817 and its very obscure effet on GDB's prompt, was never documented,
3818 tested, nor mentioned in the NEWS file.
3820 * OBSOLETE configurations and files
3822 Configurations that have been declared obsolete in this release have
3823 been commented out. Unless there is activity to revive these
3824 configurations, the next release of GDB will have their sources
3825 permanently REMOVED.
3827 Sun 3, running SunOS 3 m68*-*-sunos3*
3828 Sun 3, running SunOS 4 m68*-*-sunos4*
3829 Sun 2, running SunOS 3 m68000-*-sunos3*
3830 Sun 2, running SunOS 4 m68000-*-sunos4*
3831 Motorola 680x0 running LynxOS m68*-*-lynxos*
3832 AT&T 3b1/Unix pc m68*-att-*
3833 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3834 decstation mips-dec-* mips-little-*
3835 riscos mips-*-riscos* mips-*-sysv*
3836 sonymips mips-sony-*
3837 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3839 * REMOVED configurations and files
3841 SGI Irix-4.x mips-sgi-irix4 or iris4
3842 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3843 Z8000 simulator z8k-zilog-none or z8ksim
3844 Matsushita MN10200 w/simulator mn10200-*-*
3845 H8/500 simulator h8500-hitachi-hms or h8500hms
3846 HP/PA running BSD hppa*-*-bsd*
3847 HP/PA running OSF/1 hppa*-*-osf*
3848 HP/PA Pro target hppa*-*-pro*
3849 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3850 386BSD i[3456]86-*-bsd*
3851 Sequent family i[3456]86-sequent-sysv4*
3852 i[3456]86-sequent-sysv*
3853 i[3456]86-sequent-bsd*
3854 SPARC running LynxOS sparc-*-lynxos*
3855 SPARC running SunOS 4 sparc-*-sunos4*
3856 Tsqware Sparclet sparclet-*-*
3857 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3859 *** Changes in GDB 6.0:
3863 Support for debugging the Objective-C programming language has been
3864 integrated into GDB.
3866 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3868 DWARF 2's Call Frame Information makes available compiler generated
3869 information that more exactly describes the program's run-time stack.
3870 By using this information, GDB is able to provide more robust stack
3873 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3874 have been updated to use a new backtrace mechanism which includes
3875 DWARF 2 CFI support.
3879 GDB's remote protocol has been extended to include support for hosted
3880 file I/O (where the remote target uses GDB's file system). See GDB's
3881 remote protocol documentation for details.
3883 * All targets using the new architecture framework.
3885 All of GDB's targets have been updated to use the new internal
3886 architecture framework. The way is now open for future GDB releases
3887 to include cross-architecture native debugging support (i386 on amd64,
3890 * GNU/Linux's Thread Local Storage (TLS)
3892 GDB now includes support for for the GNU/Linux implementation of
3893 per-thread variables.
3895 * GNU/Linux's Native POSIX Thread Library (NPTL)
3897 GDB's thread code has been updated to work with either the new
3898 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3900 * Separate debug info.
3902 GDB, in conjunction with BINUTILS, now supports a mechanism for
3903 automatically loading debug information from a separate file. Instead
3904 of shipping full debug and non-debug versions of system libraries,
3905 system integrators can now instead ship just the stripped libraries
3906 and optional debug files.
3908 * DWARF 2 Location Expressions
3910 DWARF 2 Location Expressions allow the compiler to more completely
3911 describe the location of variables (even in optimized code) to the
3914 GDB now includes preliminary support for location expressions (support
3915 for DW_OP_piece is still missing).
3919 A number of long standing bugs that caused GDB to die while starting a
3920 Java application have been fixed. GDB's Java support is now
3921 considered "useable".
3923 * GNU/Linux support for fork, vfork, and exec.
3925 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3926 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3929 * GDB supports logging output to a file
3931 There are two new commands, "set logging" and "show logging", which can be
3932 used to capture GDB's output to a file.
3934 * The meaning of "detach" has changed for gdbserver
3936 The "detach" command will now resume the application, as documented. To
3937 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3940 * d10v, m68hc11 `regs' command deprecated
3942 The `info registers' command has been updated so that it displays the
3943 registers using a format identical to the old `regs' command.
3947 A new command, "maint set profile on/off", has been added. This command can
3948 be used to enable or disable profiling while running GDB, to profile a
3949 session or a set of commands. In addition there is a new configure switch,
3950 "--enable-profiling", which will cause GDB to be compiled with profiling
3951 data, for more informative profiling results.
3953 * Default MI syntax changed to "mi2".
3955 The default MI (machine interface) syntax, enabled by the command line
3956 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3957 "mi1", can be enabled by specifying the option "-i=mi1".
3959 Support for the original "mi0" syntax (included in GDB 5.0) has been
3962 Fix for gdb/192: removed extraneous space when displaying frame level.
3963 Fix for gdb/672: update changelist is now output in mi list format.
3964 Fix for gdb/702: a -var-assign that updates the value now shows up
3965 in a subsequent -var-update.
3967 * New native configurations.
3969 FreeBSD/amd64 x86_64-*-freebsd*
3971 * Multi-arched targets.
3973 HP/PA HPUX11 hppa*-*-hpux*
3974 Renesas M32R/D w/simulator m32r-*-elf*
3976 * OBSOLETE configurations and files
3978 Configurations that have been declared obsolete in this release have
3979 been commented out. Unless there is activity to revive these
3980 configurations, the next release of GDB will have their sources
3981 permanently REMOVED.
3983 Z8000 simulator z8k-zilog-none or z8ksim
3984 Matsushita MN10200 w/simulator mn10200-*-*
3985 H8/500 simulator h8500-hitachi-hms or h8500hms
3986 HP/PA running BSD hppa*-*-bsd*
3987 HP/PA running OSF/1 hppa*-*-osf*
3988 HP/PA Pro target hppa*-*-pro*
3989 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3990 Sequent family i[3456]86-sequent-sysv4*
3991 i[3456]86-sequent-sysv*
3992 i[3456]86-sequent-bsd*
3993 Tsqware Sparclet sparclet-*-*
3994 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3996 * REMOVED configurations and files
3999 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4000 IBM AIX PS/2 i[3456]86-*-aix
4001 i386 running Mach 3.0 i[3456]86-*-mach3*
4002 i386 running Mach i[3456]86-*-mach*
4003 i386 running OSF/1 i[3456]86-*osf1mk*
4004 HP/Apollo 68k Family m68*-apollo*-sysv*,
4006 m68*-hp-bsd*, m68*-hp-hpux*
4007 Argonaut Risc Chip (ARC) arc-*-*
4008 Mitsubishi D30V d30v-*-*
4009 Fujitsu FR30 fr30-*-elf*
4010 OS/9000 i[34]86-*-os9k
4011 I960 with MON960 i960-*-coff
4013 * MIPS $fp behavior changed
4015 The convenience variable $fp, for the MIPS, now consistently returns
4016 the address of the current frame's base. Previously, depending on the
4017 context, $fp could refer to either $sp or the current frame's base
4018 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4019 The GNU Source-Level Debugger''.
4021 *** Changes in GDB 5.3:
4023 * GNU/Linux shared library multi-threaded performance improved.
4025 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4026 `/proc', in preference to `ptrace' for memory reads. This may result
4027 in an improvement in the start-up time of multi-threaded, shared
4028 library applications when run under GDB. One GDB user writes: ``loads
4029 shared libs like mad''.
4031 * ``gdbserver'' now supports multi-threaded applications on some targets
4033 Support for debugging multi-threaded applications which use
4034 the GNU/Linux LinuxThreads package has been added for
4035 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4036 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4038 * GDB now supports C/C++ preprocessor macros.
4040 GDB now expands preprocessor macro invocations in C/C++ expressions,
4041 and provides various commands for showing macro definitions and how
4044 The new command `macro expand EXPRESSION' expands any macro
4045 invocations in expression, and shows the result.
4047 The new command `show macro MACRO-NAME' shows the definition of the
4048 macro named MACRO-NAME, and where it was defined.
4050 Most compilers don't include information about macros in the debugging
4051 information by default. In GCC 3.1, for example, you need to compile
4052 your program with the options `-gdwarf-2 -g3'. If the macro
4053 information is present in the executable, GDB will read it.
4055 * Multi-arched targets.
4057 DEC Alpha (partial) alpha*-*-*
4058 DEC VAX (partial) vax-*-*
4060 National Semiconductor NS32000 (partial) ns32k-*-*
4061 Motorola 68000 (partial) m68k-*-*
4062 Motorola MCORE mcore-*-*
4066 Fujitsu FRV architecture added by Red Hat frv*-*-*
4069 * New native configurations
4071 Alpha NetBSD alpha*-*-netbsd*
4072 SH NetBSD sh*-*-netbsdelf*
4073 MIPS NetBSD mips*-*-netbsd*
4074 UltraSPARC NetBSD sparc64-*-netbsd*
4076 * OBSOLETE configurations and files
4078 Configurations that have been declared obsolete in this release have
4079 been commented out. Unless there is activity to revive these
4080 configurations, the next release of GDB will have their sources
4081 permanently REMOVED.
4083 Mitsubishi D30V d30v-*-*
4084 OS/9000 i[34]86-*-os9k
4085 IBM AIX PS/2 i[3456]86-*-aix
4086 Fujitsu FR30 fr30-*-elf*
4087 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4088 Argonaut Risc Chip (ARC) arc-*-*
4089 i386 running Mach 3.0 i[3456]86-*-mach3*
4090 i386 running Mach i[3456]86-*-mach*
4091 i386 running OSF/1 i[3456]86-*osf1mk*
4092 HP/Apollo 68k Family m68*-apollo*-sysv*,
4094 m68*-hp-bsd*, m68*-hp-hpux*
4095 I960 with MON960 i960-*-coff
4097 * OBSOLETE languages
4099 CHILL, a Pascal like language used by telecommunications companies.
4101 * REMOVED configurations and files
4103 AMD 29k family via UDI a29k-amd-udi, udi29k
4104 A29K VxWorks a29k-*-vxworks
4105 AMD 29000 embedded, using EBMON a29k-none-none
4106 AMD 29000 embedded with COFF a29k-none-coff
4107 AMD 29000 embedded with a.out a29k-none-aout
4109 testsuite/gdb.hp/gdb.threads-hp/ directory
4111 * New command "set max-user-call-depth <nnn>"
4113 This command allows the user to limit the call depth of user-defined
4114 commands. The default is 1024.
4116 * Changes in FreeBSD/i386 native debugging.
4118 Support for the "generate-core-file" has been added.
4120 * New commands "dump", "append", and "restore".
4122 These commands allow data to be copied from target memory
4123 to a bfd-format or binary file (dump and append), and back
4124 from a file into memory (restore).
4126 * Improved "next/step" support on multi-processor Alpha Tru64.
4128 The previous single-step mechanism could cause unpredictable problems,
4129 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4130 of a software single-step mechanism prevents this.
4132 *** Changes in GDB 5.2.1:
4140 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4141 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4142 Fix, by Joel Brobecker imported from mainline.
4144 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4145 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4146 Fix, by Fred Fish, imported from mainline.
4148 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4149 Surprisingly enough, it works now.
4150 By Michal Ludvig, imported from mainline.
4152 i386 hardware watchpoint support:
4153 avoid misses on second run for some targets.
4154 By Pierre Muller, imported from mainline.
4156 *** Changes in GDB 5.2:
4158 * New command "set trust-readonly-sections on[off]".
4160 This command is a hint that tells gdb that read-only sections
4161 really are read-only (ie. that their contents will not change).
4162 In this mode, gdb will go to the object file rather than the
4163 target to read memory from read-only sections (such as ".text").
4164 This can be a significant performance improvement on some
4165 (notably embedded) targets.
4167 * New command "generate-core-file" (or "gcore").
4169 This new gdb command allows the user to drop a core file of the child
4170 process state at any time. So far it's been implemented only for
4171 GNU/Linux and Solaris, but should be relatively easily ported to other
4172 hosts. Argument is core file name (defaults to core.<pid>).
4174 * New command line option
4176 GDB now accepts --pid or -p followed by a process id.
4178 * Change in command line behavior -- corefiles vs. process ids.
4180 There is a subtle behavior in the way in which GDB handles
4181 command line arguments. The first non-flag argument is always
4182 a program to debug, but the second non-flag argument may either
4183 be a corefile or a process id. Previously, GDB would attempt to
4184 open the second argument as a corefile, and if that failed, would
4185 issue a superfluous error message and then attempt to attach it as
4186 a process. Now, if the second argument begins with a non-digit,
4187 it will be treated as a corefile. If it begins with a digit,
4188 GDB will attempt to attach it as a process, and if no such process
4189 is found, will then attempt to open it as a corefile.
4191 * Changes in ARM configurations.
4193 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4194 configuration is fully multi-arch.
4196 * New native configurations
4198 ARM NetBSD arm*-*-netbsd*
4199 x86 OpenBSD i[3456]86-*-openbsd*
4200 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4201 Sparc64 running FreeBSD sparc64-*-freebsd*
4205 Sanyo XStormy16 xstormy16-elf
4207 * OBSOLETE configurations and files
4209 Configurations that have been declared obsolete in this release have
4210 been commented out. Unless there is activity to revive these
4211 configurations, the next release of GDB will have their sources
4212 permanently REMOVED.
4214 AMD 29k family via UDI a29k-amd-udi, udi29k
4215 A29K VxWorks a29k-*-vxworks
4216 AMD 29000 embedded, using EBMON a29k-none-none
4217 AMD 29000 embedded with COFF a29k-none-coff
4218 AMD 29000 embedded with a.out a29k-none-aout
4220 testsuite/gdb.hp/gdb.threads-hp/ directory
4222 * REMOVED configurations and files
4224 TI TMS320C80 tic80-*-*
4226 PowerPC Solaris powerpcle-*-solaris*
4227 PowerPC Windows NT powerpcle-*-cygwin32
4228 PowerPC Netware powerpc-*-netware*
4229 Harris/CXUX m88k m88*-harris-cxux*
4230 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4231 ns32k-utek-sysv* ns32k-utek-*
4232 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4233 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4234 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4235 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4236 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4238 * Changes to command line processing
4240 The new `--args' feature can be used to specify command-line arguments
4241 for the inferior from gdb's command line.
4243 * Changes to key bindings
4245 There is a new `operate-and-get-next' function bound to `C-o'.
4247 *** Changes in GDB 5.1.1
4249 Fix compile problem on DJGPP.
4251 Fix a problem with floating-point registers on the i386 being
4254 Fix to stop GDB crashing on .debug_str debug info.
4256 Numerous documentation fixes.
4258 Numerous testsuite fixes.
4260 *** Changes in GDB 5.1:
4262 * New native configurations
4264 Alpha FreeBSD alpha*-*-freebsd*
4265 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4266 MIPS GNU/Linux mips*-*-linux*
4267 MIPS SGI Irix 6.x mips*-sgi-irix6*
4268 ia64 AIX ia64-*-aix*
4269 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4273 Motorola 68HC11 and 68HC12 m68hc11-elf
4275 UltraSparc running GNU/Linux sparc64-*-linux*
4277 * OBSOLETE configurations and files
4279 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4280 Harris/CXUX m88k m88*-harris-cxux*
4281 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4282 ns32k-utek-sysv* ns32k-utek-*
4283 TI TMS320C80 tic80-*-*
4285 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4286 PowerPC Solaris powerpcle-*-solaris*
4287 PowerPC Windows NT powerpcle-*-cygwin32
4288 PowerPC Netware powerpc-*-netware*
4289 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4290 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4291 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4292 Apple Macintosh (MPW) host N/A
4294 stuff.c (Program to stuff files into a specially prepared space in kdb)
4295 kdb-start.c (Main loop for the standalone kernel debugger)
4297 Configurations that have been declared obsolete in this release have
4298 been commented out. Unless there is activity to revive these
4299 configurations, the next release of GDB will have their sources
4300 permanently REMOVED.
4302 * REMOVED configurations and files
4304 Altos 3068 m68*-altos-*
4305 Convex c1-*-*, c2-*-*
4307 ARM RISCix arm-*-* (as host)
4311 * GDB has been converted to ISO C.
4313 GDB's source code has been converted to ISO C. In particular, the
4314 sources are fully protoized, and rely on standard headers being
4319 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4321 * The MI enabled by default.
4323 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4324 revised and enabled by default. Packages which use GDB as a debugging
4325 engine behind a UI or another front end are encouraged to switch to
4326 using the GDB/MI interface, instead of the old annotations interface
4327 which is now deprecated.
4329 * Support for debugging Pascal programs.
4331 GDB now includes support for debugging Pascal programs. The following
4332 main features are supported:
4334 - Pascal-specific data types such as sets;
4336 - automatic recognition of Pascal sources based on file-name
4339 - Pascal-style display of data types, variables, and functions;
4341 - a Pascal expression parser.
4343 However, some important features are not yet supported.
4345 - Pascal string operations are not supported at all;
4347 - there are some problems with boolean types;
4349 - Pascal type hexadecimal constants are not supported
4350 because they conflict with the internal variables format;
4352 - support for Pascal objects and classes is not full yet;
4354 - unlike Pascal, GDB is case-sensitive for symbol names.
4356 * Changes in completion.
4358 Commands such as `shell', `run' and `set args', which pass arguments
4359 to inferior programs, now complete on file names, similar to what
4360 users expect at the shell prompt.
4362 Commands which accept locations, such as `disassemble', `print',
4363 `breakpoint', `until', etc. now complete on filenames as well as
4364 program symbols. Thus, if you type "break foob TAB", and the source
4365 files linked into the programs include `foobar.c', that file name will
4366 be one of the candidates for completion. However, file names are not
4367 considered for completion after you typed a colon that delimits a file
4368 name from a name of a function in that file, as in "break foo.c:bar".
4370 `set demangle-style' completes on available demangling styles.
4372 * New platform-independent commands:
4374 It is now possible to define a post-hook for a command as well as a
4375 hook that runs before the command. For more details, see the
4376 documentation of `hookpost' in the GDB manual.
4378 * Changes in GNU/Linux native debugging.
4380 Support for debugging multi-threaded programs has been completely
4381 revised for all platforms except m68k and sparc. You can now debug as
4382 many threads as your system allows you to have.
4384 Attach/detach is supported for multi-threaded programs.
4386 Support for SSE registers was added for x86. This doesn't work for
4387 multi-threaded programs though.
4389 * Changes in MIPS configurations.
4391 Multi-arch support is enabled for all MIPS configurations.
4393 GDB can now be built as native debugger on SGI Irix 6.x systems for
4394 debugging n32 executables. (Debugging 64-bit executables is not yet
4397 * Unified support for hardware watchpoints in all x86 configurations.
4399 Most (if not all) native x86 configurations support hardware-assisted
4400 breakpoints and watchpoints in a unified manner. This support
4401 implements debug register sharing between watchpoints, which allows to
4402 put a virtually infinite number of watchpoints on the same address,
4403 and also supports watching regions up to 16 bytes with several debug
4406 The new maintenance command `maintenance show-debug-regs' toggles
4407 debugging print-outs in functions that insert, remove, and test
4408 watchpoints and hardware breakpoints.
4410 * Changes in the DJGPP native configuration.
4412 New command ``info dos sysinfo'' displays assorted information about
4413 the CPU, OS, memory, and DPMI server.
4415 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4416 display information about segment descriptors stored in GDT, LDT, and
4419 New commands ``info dos pde'' and ``info dos pte'' display entries
4420 from Page Directory and Page Tables (for now works with CWSDPMI only).
4421 New command ``info dos address-pte'' displays the Page Table entry for
4422 a given linear address.
4424 GDB can now pass command lines longer than 126 characters to the
4425 program being debugged (requires an update to the libdbg.a library
4426 which is part of the DJGPP development kit).
4428 DWARF2 debug info is now supported.
4430 It is now possible to `step' and `next' through calls to `longjmp'.
4432 * Changes in documentation.
4434 All GDB documentation was converted to GFDL, the GNU Free
4435 Documentation License.
4437 Tracepoints-related commands are now fully documented in the GDB
4440 TUI, the Text-mode User Interface, is now documented in the manual.
4442 Tracepoints-related commands are now fully documented in the GDB
4445 The "GDB Internals" manual now has an index. It also includes
4446 documentation of `ui_out' functions, GDB coding standards, x86
4447 hardware watchpoints, and memory region attributes.
4449 * GDB's version number moved to ``version.in''
4451 The Makefile variable VERSION has been replaced by the file
4452 ``version.in''. People creating GDB distributions should update the
4453 contents of this file.
4457 GUD support is now a standard part of the EMACS distribution.
4459 *** Changes in GDB 5.0:
4461 * Improved support for debugging FP programs on x86 targets
4463 Unified and much-improved support for debugging floating-point
4464 programs on all x86 targets. In particular, ``info float'' now
4465 displays the FP registers in the same format on all x86 targets, with
4466 greater level of detail.
4468 * Improvements and bugfixes in hardware-assisted watchpoints
4470 It is now possible to watch array elements, struct members, and
4471 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4472 on x86 targets no longer erroneously trigger when the address is
4475 * Improvements in the native DJGPP version of GDB
4477 The distribution now includes all the scripts and auxiliary files
4478 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4479 machines ``out of the box''.
4481 The DJGPP version can now debug programs that use signals. It is
4482 possible to catch signals that happened in the debuggee, deliver
4483 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4484 would kill the program being debugged.) Programs that hook hardware
4485 interrupts (keyboard, timer, etc.) can also be debugged.
4487 It is now possible to debug DJGPP programs that redirect their
4488 standard handles or switch them to raw (as opposed to cooked) mode, or
4489 even close them. The command ``run < foo > bar'' works as expected,
4490 and ``info terminal'' reports useful information about the debuggee's
4491 terminal, including raw/cooked mode, redirection, etc.
4493 The DJGPP version now uses termios functions for console I/O, which
4494 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4497 DOS-style file names with drive letters are now fully supported by
4500 It is now possible to debug DJGPP programs that switch their working
4501 directory. It is also possible to rerun the debuggee any number of
4502 times without restarting GDB; thus, you can use the same setup,
4503 breakpoints, etc. for many debugging sessions.
4505 * New native configurations
4507 ARM GNU/Linux arm*-*-linux*
4508 PowerPC GNU/Linux powerpc-*-linux*
4512 Motorola MCore mcore-*-*
4513 x86 VxWorks i[3456]86-*-vxworks*
4514 PowerPC VxWorks powerpc-*-vxworks*
4515 TI TMS320C80 tic80-*-*
4517 * OBSOLETE configurations
4519 Altos 3068 m68*-altos-*
4520 Convex c1-*-*, c2-*-*
4522 ARM RISCix arm-*-* (as host)
4525 Configurations that have been declared obsolete will be commented out,
4526 but the code will be left in place. If there is no activity to revive
4527 these configurations before the next release of GDB, the sources will
4528 be permanently REMOVED.
4530 * Gould support removed
4532 Support for the Gould PowerNode and NP1 has been removed.
4534 * New features for SVR4
4536 On SVR4 native platforms (such as Solaris), if you attach to a process
4537 without first loading a symbol file, GDB will now attempt to locate and
4538 load symbols from the running process's executable file.
4540 * Many C++ enhancements
4542 C++ support has been greatly improved. Overload resolution now works properly
4543 in almost all cases. RTTI support is on the way.
4545 * Remote targets can connect to a sub-program
4547 A popen(3) style serial-device has been added. This device starts a
4548 sub-process (such as a stand-alone simulator) and then communicates
4549 with that. The sub-program to run is specified using the syntax
4550 ``|<program> <args>'' vis:
4552 (gdb) set remotedebug 1
4553 (gdb) target extended-remote |mn10300-elf-sim program-args
4555 * MIPS 64 remote protocol
4557 A long standing bug in the mips64 remote protocol where by GDB
4558 expected certain 32 bit registers (ex SR) to be transfered as 32
4559 instead of 64 bits has been fixed.
4561 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4562 added to provide backward compatibility with older versions of GDB.
4564 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4566 The command ``set remotebinarydownload'' command has been replaced by
4567 ``set remote X-packet''. Other commands in ``set remote'' family
4568 include ``set remote P-packet''.
4570 * Breakpoint commands accept ranges.
4572 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4573 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4574 ``tracepoint passcount'' also accepts a range of tracepoints.
4576 * ``apropos'' command added.
4578 The ``apropos'' command searches through command names and
4579 documentation strings, printing out matches, making it much easier to
4580 try to find a command that does what you are looking for.
4584 A new machine oriented interface (MI) has been added to GDB. This
4585 interface is designed for debug environments running GDB as a separate
4586 process. This is part of the long term libGDB project. See the
4587 "GDB/MI" chapter of the GDB manual for further information. It can be
4588 enabled by configuring with:
4590 .../configure --enable-gdbmi
4592 *** Changes in GDB-4.18:
4594 * New native configurations
4596 HP-UX 10.20 hppa*-*-hpux10.20
4597 HP-UX 11.x hppa*-*-hpux11.0*
4598 M68K GNU/Linux m68*-*-linux*
4602 Fujitsu FR30 fr30-*-elf*
4603 Intel StrongARM strongarm-*-*
4604 Mitsubishi D30V d30v-*-*
4606 * OBSOLETE configurations
4608 Gould PowerNode, NP1 np1-*-*, pn-*-*
4610 Configurations that have been declared obsolete will be commented out,
4611 but the code will be left in place. If there is no activity to revive
4612 these configurations before the next release of GDB, the sources will
4613 be permanently REMOVED.
4617 As a compatibility experiment, GDB's source files buildsym.h and
4618 buildsym.c have been converted to pure standard C, no longer
4619 containing any K&R compatibility code. We believe that all systems in
4620 use today either come with a standard C compiler, or have a GCC port
4621 available. If this is not true, please report the affected
4622 configuration to bug-gdb@gnu.org immediately. See the README file for
4623 information about getting a standard C compiler if you don't have one
4628 GDB now uses readline 2.2.
4630 * set extension-language
4632 You can now control the mapping between filename extensions and source
4633 languages by using the `set extension-language' command. For instance,
4634 you can ask GDB to treat .c files as C++ by saying
4635 set extension-language .c c++
4636 The command `info extensions' lists all of the recognized extensions
4637 and their associated languages.
4639 * Setting processor type for PowerPC and RS/6000
4641 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4642 you can use the `set processor' command to specify what variant of the
4643 PowerPC family you are debugging. The command
4647 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4648 following PowerPC and RS6000 variants:
4650 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4651 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4653 403GC IBM PowerPC 403GC
4654 505 Motorola PowerPC 505
4655 860 Motorola PowerPC 860 or 850
4656 601 Motorola PowerPC 601
4657 602 Motorola PowerPC 602
4658 603 Motorola/IBM PowerPC 603 or 603e
4659 604 Motorola PowerPC 604 or 604e
4660 750 Motorola/IBM PowerPC 750 or 750
4662 At the moment, this command just tells GDB what to name the
4663 special-purpose processor registers. Since almost all the affected
4664 registers are inaccessible to user-level programs, this command is
4665 only useful for remote debugging in its present form.
4669 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4670 more extensive support for HP-UX. Added features include shared
4671 library support, kernel threads and hardware watchpoints for 11.00,
4672 support for HP's ANSI C and C++ compilers, and a compatibility mode
4673 for xdb and dbx commands.
4677 HP's donation includes the new concept of catchpoints, which is a
4678 generalization of the old catch command. On HP-UX, it is now possible
4679 to catch exec, fork, and vfork, as well as library loading.
4681 This means that the existing catch command has changed; its first
4682 argument now specifies the type of catch to be set up. See the
4683 output of "help catch" for a list of catchpoint types.
4685 * Debugging across forks
4687 On HP-UX, you can choose which process to debug when a fork() happens
4692 HP has donated a curses-based terminal user interface (TUI). To get
4693 it, build with --enable-tui. Although this can be enabled for any
4694 configuration, at present it only works for native HP debugging.
4696 * GDB remote protocol additions
4698 A new protocol packet 'X' that writes binary data is now available.
4699 Default behavior is to try 'X', then drop back to 'M' if the stub
4700 fails to respond. The settable variable `remotebinarydownload'
4701 allows explicit control over the use of 'X'.
4703 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4704 full 64-bit address. The command
4706 set remoteaddresssize 32
4708 can be used to revert to the old behaviour. For existing remote stubs
4709 the change should not be noticed, as the additional address information
4712 In order to assist in debugging stubs, you may use the maintenance
4713 command `packet' to send any text string to the stub. For instance,
4715 maint packet heythere
4717 sends the packet "$heythere#<checksum>". Note that it is very easy to
4718 disrupt a debugging session by sending the wrong packet at the wrong
4721 The compare-sections command allows you to compare section data on the
4722 target to what is in the executable file without uploading or
4723 downloading, by comparing CRC checksums.
4725 * Tracing can collect general expressions
4727 You may now collect general expressions at tracepoints. This requires
4728 further additions to the target-side stub; see tracepoint.c and
4729 doc/agentexpr.texi for further details.
4731 * mask-address variable for Mips
4733 For Mips targets, you may control the zeroing of the upper 32 bits of
4734 a 64-bit address by entering `set mask-address on'. This is mainly
4735 of interest to users of embedded R4xxx and R5xxx processors.
4737 * Higher serial baud rates
4739 GDB's serial code now allows you to specify baud rates 57600, 115200,
4740 230400, and 460800 baud. (Note that your host system may not be able
4741 to achieve all of these rates.)
4745 The i960 configuration now includes an initial implementation of a
4746 builtin simulator, contributed by Jim Wilson.
4749 *** Changes in GDB-4.17:
4751 * New native configurations
4753 Alpha GNU/Linux alpha*-*-linux*
4754 Unixware 2.x i[3456]86-unixware2*
4755 Irix 6.x mips*-sgi-irix6*
4756 PowerPC GNU/Linux powerpc-*-linux*
4757 PowerPC Solaris powerpcle-*-solaris*
4758 Sparc GNU/Linux sparc-*-linux*
4759 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4763 Argonaut Risc Chip (ARC) arc-*-*
4764 Hitachi H8/300S h8300*-*-*
4765 Matsushita MN10200 w/simulator mn10200-*-*
4766 Matsushita MN10300 w/simulator mn10300-*-*
4767 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4768 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4769 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4770 Mitsubishi D10V w/simulator d10v-*-*
4771 Mitsubishi M32R/D w/simulator m32r-*-elf*
4772 Tsqware Sparclet sparclet-*-*
4773 NEC V850 w/simulator v850-*-*
4775 * New debugging protocols
4777 ARM with RDI protocol arm*-*-*
4778 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4779 DDB and LSI variants of PMON protocol mips*-*-*
4780 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4781 PowerPC with SDS protocol powerpc{,le}-*-eabi
4782 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4786 All configurations can now understand and use the DWARF 2 debugging
4787 format. The choice is automatic, if the symbol file contains DWARF 2
4792 GDB now includes basic Java language support. This support is
4793 only useful with Java compilers that produce native machine code.
4795 * solib-absolute-prefix and solib-search-path
4797 For SunOS and SVR4 shared libraries, you may now set the prefix for
4798 loading absolute shared library symbol files, and the search path for
4799 locating non-absolute shared library symbol files.
4801 * Live range splitting
4803 GDB can now effectively debug code for which GCC has performed live
4804 range splitting as part of its optimization. See gdb/doc/LRS for
4805 more details on the expected format of the stabs information.
4809 GDB's support for the GNU Hurd, including thread debugging, has been
4810 updated to work with current versions of the Hurd.
4814 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4815 instruction set. ARM GDB automatically detects when Thumb
4816 instructions are in use, and adjusts disassembly and backtracing
4821 GDB's MIPS target configurations now handle the MIP16 16-bit
4826 GDB now includes support for overlays; if an executable has been
4827 linked such that multiple sections are based at the same address, GDB
4828 will decide which section to use for symbolic info. You can choose to
4829 control the decision manually, using overlay commands, or implement
4830 additional target-side support and use "overlay load-target" to bring
4831 in the overlay mapping. Do "help overlay" for more detail.
4835 The command "info symbol <address>" displays information about
4836 the symbol at the specified address.
4840 The standard remote protocol now includes an extension that allows
4841 asynchronous collection and display of trace data. This requires
4842 extensive support in the target-side debugging stub. Tracing mode
4843 includes a new interaction mode in GDB and new commands: see the
4844 file tracepoint.c for more details.
4848 Configurations for embedded MIPS now include a simulator contributed
4849 by Cygnus Solutions. The simulator supports the instruction sets
4850 of most MIPS variants.
4854 Sparc configurations may now include the ERC32 simulator contributed
4855 by the European Space Agency. The simulator is not built into
4856 Sparc targets by default; configure with --enable-sim to include it.
4860 For target configurations that may include multiple variants of a
4861 basic architecture (such as MIPS and SH), you may now set the
4862 architecture explicitly. "set arch" sets, "info arch" lists
4863 the possible architectures.
4865 *** Changes in GDB-4.16:
4867 * New native configurations
4869 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4870 M68K NetBSD m68k-*-netbsd*
4871 PowerPC AIX 4.x powerpc-*-aix*
4872 PowerPC MacOS powerpc-*-macos*
4873 PowerPC Windows NT powerpcle-*-cygwin32
4874 RS/6000 AIX 4.x rs6000-*-aix4*
4878 ARM with RDP protocol arm-*-*
4879 I960 with MON960 i960-*-coff
4880 MIPS VxWorks mips*-*-vxworks*
4881 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4882 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4884 Matra Sparclet sparclet-*-*
4888 The powerpc-eabi configuration now includes the PSIM simulator,
4889 contributed by Andrew Cagney, with assistance from Mike Meissner.
4890 PSIM is a very elaborate model of the PowerPC, including not only
4891 basic instruction set execution, but also details of execution unit
4892 performance and I/O hardware. See sim/ppc/README for more details.
4896 GDB now works with Solaris 2.5.
4898 * Windows 95/NT native
4900 GDB will now work as a native debugger on Windows 95 and Windows NT.
4901 To build it from source, you must use the "gnu-win32" environment,
4902 which uses a DLL to emulate enough of Unix to run the GNU tools.
4903 Further information, binaries, and sources are available at
4904 ftp.cygnus.com, under pub/gnu-win32.
4906 * dont-repeat command
4908 If a user-defined command includes the command `dont-repeat', then the
4909 command will not be repeated if the user just types return. This is
4910 useful if the command is time-consuming to run, so that accidental
4911 extra keystrokes don't run the same command many times.
4913 * Send break instead of ^C
4915 The standard remote protocol now includes an option to send a break
4916 rather than a ^C to the target in order to interrupt it. By default,
4917 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4919 * Remote protocol timeout
4921 The standard remote protocol includes a new variable `remotetimeout'
4922 that allows you to set the number of seconds before GDB gives up trying
4923 to read from the target. The default value is 2.
4925 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4927 By default GDB will automatically keep track of objects as they are
4928 loaded and unloaded by the dynamic linker. By using the command `set
4929 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4930 when shared library events occur, thus allowing you to set breakpoints
4931 in shared libraries which are explicitly loaded by the inferior.
4933 Note this feature does not work on hpux8. On hpux9 you must link
4934 /usr/lib/end.o into your program. This feature should work
4935 automatically on hpux10.
4937 * Irix 5.x hardware watchpoint support
4939 Irix 5 configurations now support the use of hardware watchpoints.
4941 * Mips protocol "SYN garbage limit"
4943 When debugging a Mips target using the `target mips' protocol, you
4944 may set the number of characters that GDB will ignore by setting
4945 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4946 every character. The default value is 1050.
4948 * Recording and replaying remote debug sessions
4950 If you set `remotelogfile' to the name of a file, gdb will write to it
4951 a recording of a remote debug session. This recording may then be
4952 replayed back to gdb using "gdbreplay". See gdbserver/README for
4953 details. This is useful when you have a problem with GDB while doing
4954 remote debugging; you can make a recording of the session and send it
4955 to someone else, who can then recreate the problem.
4957 * Speedups for remote debugging
4959 GDB includes speedups for downloading and stepping MIPS systems using
4960 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4961 and more efficient S-record downloading.
4963 * Memory use reductions and statistics collection
4965 GDB now uses less memory and reports statistics about memory usage.
4966 Try the `maint print statistics' command, for example.
4968 *** Changes in GDB-4.15:
4970 * Psymtabs for XCOFF
4972 The symbol reader for AIX GDB now uses partial symbol tables. This
4973 can greatly improve startup time, especially for large executables.
4975 * Remote targets use caching
4977 Remote targets now use a data cache to speed up communication with the
4978 remote side. The data cache could lead to incorrect results because
4979 it doesn't know about volatile variables, thus making it impossible to
4980 debug targets which use memory mapped I/O devices. `set remotecache
4981 off' turns the the data cache off.
4983 * Remote targets may have threads
4985 The standard remote protocol now includes support for multiple threads
4986 in the target system, using new protocol commands 'H' and 'T'. See
4987 gdb/remote.c for details.
4991 If GDB is configured with `--enable-netrom', then it will include
4992 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4993 acts as though it is a bank of ROM on the target board, but you can
4994 write into it over the network. GDB's support consists only of
4995 support for fast loading into the emulated ROM; to debug, you must use
4996 another protocol, such as standard remote protocol. The usual
4997 sequence is something like
4999 target nrom <netrom-hostname>
5001 target remote <netrom-hostname>:1235
5005 GDB now includes support for the Apple Macintosh, as a host only. It
5006 may be run as either an MPW tool or as a standalone application, and
5007 it can debug through the serial port. All the usual GDB commands are
5008 available, but to the target command, you must supply "serial" as the
5009 device type instead of "/dev/ttyXX". See mpw-README in the main
5010 directory for more information on how to build. The MPW configuration
5011 scripts */mpw-config.in support only a few targets, and only the
5012 mips-idt-ecoff target has been tested.
5016 GDB configuration now uses autoconf. This is not user-visible,
5017 but does simplify configuration and building.
5021 GDB now supports hpux10.
5023 *** Changes in GDB-4.14:
5025 * New native configurations
5027 x86 FreeBSD i[345]86-*-freebsd
5028 x86 NetBSD i[345]86-*-netbsd
5029 NS32k NetBSD ns32k-*-netbsd
5030 Sparc NetBSD sparc-*-netbsd
5034 A29K VxWorks a29k-*-vxworks
5035 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5036 CPU32 EST-300 emulator m68*-*-est*
5037 PowerPC ELF powerpc-*-elf
5040 * Alpha OSF/1 support for procfs
5042 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5043 possible to attach to running processes. As the mounting of the /proc
5044 filesystem is optional on the Alpha, GDB automatically determines
5045 the availability of /proc during startup. This can lead to problems
5046 if /proc is unmounted after GDB has been started.
5048 * Arguments to user-defined commands
5050 User commands may accept up to 10 arguments separated by whitespace.
5051 Arguments are accessed within the user command via $arg0..$arg9. A
5054 print $arg0 + $arg1 + $arg2
5056 To execute the command use:
5059 Defines the command "adder" which prints the sum of its three arguments.
5060 Note the arguments are text substitutions, so they may reference variables,
5061 use complex expressions, or even perform inferior function calls.
5063 * New `if' and `while' commands
5065 This makes it possible to write more sophisticated user-defined
5066 commands. Both commands take a single argument, which is the
5067 expression to evaluate, and must be followed by the commands to
5068 execute, one per line, if the expression is nonzero, the list being
5069 terminated by the word `end'. The `if' command list may include an
5070 `else' word, which causes the following commands to be executed only
5071 if the expression is zero.
5073 * Fortran source language mode
5075 GDB now includes partial support for Fortran 77. It will recognize
5076 Fortran programs and can evaluate a subset of Fortran expressions, but
5077 variables and functions may not be handled correctly. GDB will work
5078 with G77, but does not yet know much about symbols emitted by other
5081 * Better HPUX support
5083 Most debugging facilities now work on dynamic executables for HPPAs
5084 running hpux9 or later. You can attach to running dynamically linked
5085 processes, but by default the dynamic libraries will be read-only, so
5086 for instance you won't be able to put breakpoints in them. To change
5087 that behavior do the following before running the program:
5093 This will cause the libraries to be mapped private and read-write.
5094 To revert to the normal behavior, do this:
5100 You cannot set breakpoints or examine data in the library until after
5101 the library is loaded if the function/data symbols do not have
5104 GDB can now also read debug symbols produced by the HP C compiler on
5105 HPPAs (sorry, no C++, Fortran or 68k support).
5107 * Target byte order now dynamically selectable
5109 You can choose which byte order to use with a target system, via the
5110 commands "set endian big" and "set endian little", and you can see the
5111 current setting by using "show endian". You can also give the command
5112 "set endian auto", in which case GDB will use the byte order
5113 associated with the executable. Currently, only embedded MIPS
5114 configurations support dynamic selection of target byte order.
5116 * New DOS host serial code
5118 This version uses DPMI interrupts to handle buffered I/O, so you
5119 no longer need to run asynctsr when debugging boards connected to
5122 *** Changes in GDB-4.13:
5124 * New "complete" command
5126 This lists all the possible completions for the rest of the line, if it
5127 were to be given as a command itself. This is intended for use by emacs.
5129 * Trailing space optional in prompt
5131 "set prompt" no longer adds a space for you after the prompt you set. This
5132 allows you to set a prompt which ends in a space or one that does not.
5134 * Breakpoint hit counts
5136 "info break" now displays a count of the number of times the breakpoint
5137 has been hit. This is especially useful in conjunction with "ignore"; you
5138 can ignore a large number of breakpoint hits, look at the breakpoint info
5139 to see how many times the breakpoint was hit, then run again, ignoring one
5140 less than that number, and this will get you quickly to the last hit of
5143 * Ability to stop printing at NULL character
5145 "set print null-stop" will cause GDB to stop printing the characters of
5146 an array when the first NULL is encountered. This is useful when large
5147 arrays actually contain only short strings.
5149 * Shared library breakpoints
5151 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5152 breakpoints in shared libraries before the executable is run.
5154 * Hardware watchpoints
5156 There is a new hardware breakpoint for the watch command for sparclite
5157 targets. See gdb/sparclite/hw_breakpoint.note.
5159 Hardware watchpoints are also now supported under GNU/Linux.
5163 Annotations have been added. These are for use with graphical interfaces,
5164 and are still experimental. Currently only gdba.el uses these.
5166 * Improved Irix 5 support
5168 GDB now works properly with Irix 5.2.
5170 * Improved HPPA support
5172 GDB now works properly with the latest GCC and GAS.
5174 * New native configurations
5176 Sequent PTX4 i[34]86-sequent-ptx4
5177 HPPA running OSF/1 hppa*-*-osf*
5178 Atari TT running SVR4 m68*-*-sysv4*
5179 RS/6000 LynxOS rs6000-*-lynxos*
5183 OS/9000 i[34]86-*-os9k
5184 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5187 * Hitachi SH7000 and E7000-PC ICE support
5189 There is now support for communicating with the Hitachi E7000-PC ICE.
5190 This is available automatically when GDB is configured for the SH.
5194 As usual, a variety of small fixes and improvements, both generic
5195 and configuration-specific. See the ChangeLog for more detail.
5197 *** Changes in GDB-4.12:
5199 * Irix 5 is now supported
5203 GDB-4.12 on the HPPA has a number of changes which make it unable
5204 to debug the output from the currently released versions of GCC and
5205 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5206 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5207 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5210 *** Changes in GDB-4.11:
5212 * User visible changes:
5216 The "set remotedebug" option is now consistent between the mips remote
5217 target, remote targets using the gdb-specific protocol, UDI (AMD's
5218 debug protocol for the 29k) and the 88k bug monitor. It is now an
5219 integer specifying a debug level (normally 0 or 1, but 2 means more
5220 debugging info for the mips target).
5222 * DEC Alpha native support
5224 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5225 debug info, but GDB works fairly well with the DEC compiler and should
5226 work with a future GCC release. See the README file for a few
5227 Alpha-specific notes.
5229 * Preliminary thread implementation
5231 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5233 * LynxOS native and target support for 386
5235 This release has been hosted on LynxOS 2.2, and also can be configured
5236 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5239 * Improvements in C++ mangling/demangling.
5241 This release has much better g++ debugging, specifically in name
5242 mangling/demangling, virtual function calls, print virtual table,
5243 call methods, ...etc.
5245 *** Changes in GDB-4.10:
5247 * User visible changes:
5249 Remote debugging using the GDB-specific (`target remote') protocol now
5250 supports the `load' command. This is only useful if you have some
5251 other way of getting the stub to the target system, and you can put it
5252 somewhere in memory where it won't get clobbered by the download.
5254 Filename completion now works.
5256 When run under emacs mode, the "info line" command now causes the
5257 arrow to point to the line specified. Also, "info line" prints
5258 addresses in symbolic form (as well as hex).
5260 All vxworks based targets now support a user settable option, called
5261 vxworks-timeout. This option represents the number of seconds gdb
5262 should wait for responses to rpc's. You might want to use this if
5263 your vxworks target is, perhaps, a slow software simulator or happens
5264 to be on the far side of a thin network line.
5268 This release contains support for using a DEC alpha as a GDB host for
5269 cross debugging. Native alpha debugging is not supported yet.
5272 *** Changes in GDB-4.9:
5276 This is the first GDB release which is accompanied by a matching testsuite.
5277 The testsuite requires installation of dejagnu, which should be available
5278 via ftp from most sites that carry GNU software.
5282 'Cfront' style demangling has had its name changed to 'ARM' style, to
5283 emphasize that it was written from the specifications in the C++ Annotated
5284 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5285 disclaimers, it still generated too much confusion with users attempting to
5286 use gdb with AT&T cfront.
5290 GDB now uses a standard remote interface to a simulator library.
5291 So far, the library contains simulators for the Zilog Z8001/2, the
5292 Hitachi H8/300, H8/500 and Super-H.
5294 * New targets supported
5296 H8/300 simulator h8300-hitachi-hms or h8300hms
5297 H8/500 simulator h8500-hitachi-hms or h8500hms
5298 SH simulator sh-hitachi-hms or sh
5299 Z8000 simulator z8k-zilog-none or z8ksim
5300 IDT MIPS board over serial line mips-idt-ecoff
5302 Cross-debugging to GO32 targets is supported. It requires a custom
5303 version of the i386-stub.c module which is integrated with the
5304 GO32 memory extender.
5306 * New remote protocols
5308 MIPS remote debugging protocol.
5310 * New source languages supported
5312 This version includes preliminary support for Chill, a Pascal like language
5313 used by telecommunications companies. Chill support is also being integrated
5314 into the GNU compiler, but we don't know when it will be publically available.
5317 *** Changes in GDB-4.8:
5319 * HP Precision Architecture supported
5321 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5322 version of this support was available as a set of patches from the
5323 University of Utah. GDB does not support debugging of programs
5324 compiled with the HP compiler, because HP will not document their file
5325 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5326 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5328 Many problems in the preliminary version have been fixed.
5330 * Faster and better demangling
5332 We have improved template demangling and fixed numerous bugs in the GNU style
5333 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5334 character types (wchar_t) are now supported. Demangling of each symbol is now
5335 only done once, and is cached when the symbol table for a file is read in.
5336 This results in a small increase in memory usage for C programs, a moderate
5337 increase in memory usage for C++ programs, and a fantastic speedup in
5340 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5341 from the specifications in the Annotated Reference Manual, which AT&T's
5342 compiler does not actually implement.
5344 * G++ multiple inheritance compiler problem
5346 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5347 inheritance lattices was reworked to properly discover ambiguities. We
5348 recently found an example which causes this new algorithm to fail in a
5349 very subtle way, producing bad debug information for those classes.
5350 The file 'gcc.patch' (in this directory) can be applied to gcc to
5351 circumvent the problem. A future GCC release will contain a complete
5354 The previous G++ debug info problem (mentioned below for the gdb-4.7
5355 release) is fixed in gcc version 2.3.2.
5357 * Improved configure script
5359 The `configure' script will now attempt to guess your system type if
5360 you don't supply a host system type. The old scheme of supplying a
5361 host system triplet is preferable over using this. All the magic is
5362 done in the new `config.guess' script. Examine it for details.
5364 We have also brought our configure script much more in line with the FSF's
5365 version. It now supports the --with-xxx options. In particular,
5366 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5367 The resulting GDB will not be able to read arbitrary object file formats --
5368 only the format ``expected'' to be used on the configured target system.
5369 We hope to make this the default in a future release.
5371 * Documentation improvements
5373 There's new internal documentation on how to modify GDB, and how to
5374 produce clean changes to the code. We implore people to read it
5375 before submitting changes.
5377 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5378 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5379 `info' files are also provided. To build `info' files from scratch,
5380 you will need the latest `makeinfo' release, which will be available in
5381 a future texinfo-X.Y release.
5383 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5384 We're not sure exactly which versions have this problem, but it has
5385 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5386 or better. If that isn't possible, there is a patch in
5387 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5388 around this problem.
5392 GDB now supports array constants that can be used in expressions typed in by
5393 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5394 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5397 The new directory `gdb/sparclite' contains a program that demonstrates
5398 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5400 * New native hosts supported
5402 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5403 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5405 * New targets supported
5407 AMD 29k family via UDI a29k-amd-udi or udi29k
5409 * New file formats supported
5411 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5412 HPUX core files, and SCO 3.2v2 core files.
5416 Attaching to processes now works again; thanks for the many bug reports.
5418 We have also stomped on a bunch of core dumps caused by
5419 printf_filtered("%s") problems.
5421 We eliminated a copyright problem on the rpc and ptrace header files
5422 for VxWorks, which was discovered at the last minute during the 4.7
5423 release. You should now be able to build a VxWorks GDB.
5425 You can now interrupt gdb while an attached process is running. This
5426 will cause the attached process to stop, and give control back to GDB.
5428 We fixed problems caused by using too many file descriptors
5429 for reading symbols from object files and libraries. This was
5430 especially a problem for programs that used many (~100) shared
5433 The `step' command now only enters a subroutine if there is line number
5434 information for the subroutine. Otherwise it acts like the `next'
5435 command. Previously, `step' would enter subroutines if there was
5436 any debugging information about the routine. This avoids problems
5437 when using `cc -g1' on MIPS machines.
5439 * Internal improvements
5441 GDB's internal interfaces have been improved to make it easier to support
5442 debugging of multiple languages in the future.
5444 GDB now uses a common structure for symbol information internally.
5445 Minimal symbols (derived from linkage symbols in object files), partial
5446 symbols (from a quick scan of debug information), and full symbols
5447 contain a common subset of information, making it easier to write
5448 shared code that handles any of them.
5450 * New command line options
5452 We now accept --silent as an alias for --quiet.
5456 The memory-mapped-malloc library is now licensed under the GNU Library
5457 General Public License.
5459 *** Changes in GDB-4.7:
5461 * Host/native/target split
5463 GDB has had some major internal surgery to untangle the support for
5464 hosts and remote targets. Now, when you configure GDB for a remote
5465 target, it will no longer load in all of the support for debugging
5466 local programs on the host. When fully completed and tested, this will
5467 ensure that arbitrary host/target combinations are possible.
5469 The primary conceptual shift is to separate the non-portable code in
5470 GDB into three categories. Host specific code is required any time GDB
5471 is compiled on that host, regardless of the target. Target specific
5472 code relates to the peculiarities of the target, but can be compiled on
5473 any host. Native specific code is everything else: it can only be
5474 built when the host and target are the same system. Child process
5475 handling and core file support are two common `native' examples.
5477 GDB's use of /proc for controlling Unix child processes is now cleaner.
5478 It has been split out into a single module under the `target_ops' vector,
5479 plus two native-dependent functions for each system that uses /proc.
5481 * New hosts supported
5483 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5484 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5485 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5487 * New targets supported
5489 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5490 68030 and CPU32 m68030-*-*, m68332-*-*
5492 * New native hosts supported
5494 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5495 (386bsd is not well tested yet)
5496 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5498 * New file formats supported
5500 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5501 supports reading of `a.out.adobe' object files, which are an a.out
5502 format extended with minimal information about multiple sections.
5506 `show copying' is the same as the old `info copying'.
5507 `show warranty' is the same as `info warrantee'.
5508 These were renamed for consistency. The old commands continue to work.
5510 `info handle' is a new alias for `info signals'.
5512 You can now define pre-command hooks, which attach arbitrary command
5513 scripts to any command. The commands in the hook will be executed
5514 prior to the user's command. You can also create a hook which will be
5515 executed whenever the program stops. See gdb.texinfo.
5519 We now deal with Cfront style name mangling, and can even extract type
5520 info from mangled symbols. GDB can automatically figure out which
5521 symbol mangling style your C++ compiler uses.
5523 Calling of methods and virtual functions has been improved as well.
5527 The crash that occured when debugging Sun Ansi-C compiled binaries is
5528 fixed. This was due to mishandling of the extra N_SO stabs output
5531 We also finally got Ultrix 4.2 running in house, and fixed core file
5532 support, with help from a dozen people on the net.
5534 John M. Farrell discovered that the reason that single-stepping was so
5535 slow on all of the Mips based platforms (primarily SGI and DEC) was
5536 that we were trying to demangle and lookup a symbol used for internal
5537 purposes on every instruction that was being stepped through. Changing
5538 the name of that symbol so that it couldn't be mistaken for a C++
5539 mangled symbol sped things up a great deal.
5541 Rich Pixley sped up symbol lookups in general by getting much smarter
5542 about when C++ symbol mangling is necessary. This should make symbol
5543 completion (TAB on the command line) much faster. It's not as fast as
5544 we'd like, but it's significantly faster than gdb-4.6.
5548 A new user controllable variable 'call_scratch_address' can
5549 specify the location of a scratch area to be used when GDB
5550 calls a function in the target. This is necessary because the
5551 usual method of putting the scratch area on the stack does not work
5552 in systems that have separate instruction and data spaces.
5554 We integrated changes to support the 29k UDI (Universal Debugger
5555 Interface), but discovered at the last minute that we didn't have all
5556 of the appropriate copyright paperwork. We are working with AMD to
5557 resolve this, and hope to have it available soon.
5561 We have sped up the remote serial line protocol, especially for targets
5562 with lots of registers. It now supports a new `expedited status' ('T')
5563 message which can be used in place of the existing 'S' status message.
5564 This allows the remote stub to send only the registers that GDB
5565 needs to make a quick decision about single-stepping or conditional
5566 breakpoints, eliminating the need to fetch the entire register set for
5567 each instruction being stepped through.
5569 The GDB remote serial protocol now implements a write-through cache for
5570 registers, only re-reading the registers if the target has run.
5572 There is also a new remote serial stub for SPARC processors. You can
5573 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5574 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5575 processor with a serial port.
5579 Configure.in files have become much easier to read and modify. A new
5580 `table driven' format makes it more obvious what configurations are
5581 supported, and what files each one uses.
5585 There is a new opcodes library which will eventually contain all of the
5586 disassembly routines and opcode tables. At present, it only contains
5587 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5588 disassembler (binutils/objdump) to share these routines.
5590 The libiberty library is now copylefted under the GNU Library General
5591 Public License. This allows more liberal use, and was done so libg++
5592 can use it. This makes no difference to GDB, since the Library License
5593 grants all the rights from the General Public License.
5597 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5598 reference to the stabs symbol info used by the debugger. It is (as far
5599 as we know) the only published document on this fascinating topic. We
5600 encourage you to read it, compare it to the stabs information on your
5601 system, and send improvements on the document in general (to
5602 bug-gdb@prep.ai.mit.edu).
5604 And, of course, many bugs have been fixed.
5607 *** Changes in GDB-4.6:
5609 * Better support for C++ function names
5611 GDB now accepts as input the "demangled form" of C++ overloaded function
5612 names and member function names, and can do command completion on such names
5613 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5614 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5615 Make use of command completion, it is your friend.
5617 GDB also now accepts a variety of C++ mangled symbol formats. They are
5618 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5619 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5620 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5621 for the list of formats.
5623 * G++ symbol mangling problem
5625 Recent versions of gcc have a bug in how they emit debugging information for
5626 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5627 directory) can be applied to gcc to fix the problem. Alternatively, if you
5628 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5629 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5630 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5633 * New 'maintenance' command
5635 All of the commands related to hacking GDB internals have been moved out of
5636 the main command set, and now live behind the 'maintenance' command. This
5637 can also be abbreviated as 'mt'. The following changes were made:
5639 dump-me -> maintenance dump-me
5640 info all-breakpoints -> maintenance info breakpoints
5641 printmsyms -> maintenance print msyms
5642 printobjfiles -> maintenance print objfiles
5643 printpsyms -> maintenance print psymbols
5644 printsyms -> maintenance print symbols
5646 The following commands are new:
5648 maintenance demangle Call internal GDB demangler routine to
5649 demangle a C++ link name and prints the result.
5650 maintenance print type Print a type chain for a given symbol
5652 * Change to .gdbinit file processing
5654 We now read the $HOME/.gdbinit file before processing the argv arguments
5655 (e.g. reading symbol files or core files). This allows global parameters to
5656 be set, which will apply during the symbol reading. The ./.gdbinit is still
5657 read after argv processing.
5659 * New hosts supported
5661 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5663 GNU/Linux support i386-unknown-linux or linux
5665 We are also including code to support the HP/PA running BSD and HPUX. This
5666 is almost guaranteed not to work, as we didn't have time to test or build it
5667 for this release. We are including it so that the more adventurous (or
5668 masochistic) of you can play with it. We also had major problems with the
5669 fact that the compiler that we got from HP doesn't support the -g option.
5672 * New targets supported
5674 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5676 * More smarts about finding #include files
5678 GDB now remembers the compilation directory for all include files, and for
5679 all files from which C is generated (like yacc and lex sources). This
5680 greatly improves GDB's ability to find yacc/lex sources, and include files,
5681 especially if you are debugging your program from a directory different from
5682 the one that contains your sources.
5684 We also fixed a bug which caused difficulty with listing and setting
5685 breakpoints in include files which contain C code. (In the past, you had to
5686 try twice in order to list an include file that you hadn't looked at before.)
5688 * Interesting infernals change
5690 GDB now deals with arbitrary numbers of sections, where the symbols for each
5691 section must be relocated relative to that section's landing place in the
5692 target's address space. This work was needed to support ELF with embedded
5693 stabs used by Solaris-2.0.
5695 * Bug fixes (of course!)
5697 There have been loads of fixes for the following things:
5698 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5699 i960, stabs, DOS(GO32), procfs, etc...
5701 See the ChangeLog for details.
5703 *** Changes in GDB-4.5:
5705 * New machines supported (host and target)
5707 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5709 SGI Irix-4.x mips-sgi-irix4 or iris4
5711 * New malloc package
5713 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5714 Mmalloc is capable of handling mutiple heaps of memory. It is also
5715 capable of saving a heap to a file, and then mapping it back in later.
5716 This can be used to greatly speedup the startup of GDB by using a
5717 pre-parsed symbol table which lives in a mmalloc managed heap. For
5718 more details, please read mmalloc/mmalloc.texi.
5722 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5723 'help info proc' for details.
5725 * MIPS ecoff symbol table format
5727 The code that reads MIPS symbol table format is now supported on all hosts.
5728 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5731 * File name changes for MS-DOS
5733 Many files in the config directories have been renamed to make it easier to
5734 support GDB on MS-DOSe systems (which have very restrictive file name
5735 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5736 environment) is close to working but has some remaining problems. Note
5737 that debugging of DOS programs is not supported, due to limitations
5738 in the ``operating system'', but it can be used to host cross-debugging.
5740 * Cross byte order fixes
5742 Many fixes have been made to support cross debugging of Sparc and MIPS
5743 targets from hosts whose byte order differs.
5745 * New -mapped and -readnow options
5747 If memory-mapped files are available on your system through the 'mmap'
5748 system call, you can use the -mapped option on the `file' or
5749 `symbol-file' commands to cause GDB to write the symbols from your
5750 program into a reusable file. If the program you are debugging is
5751 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5752 Future GDB debugging sessions will notice the presence of this file,
5753 and will quickly map in symbol information from it, rather than reading
5754 the symbol table from the executable program. Using the '-mapped'
5755 option in a GDB `file' or `symbol-file' command has the same effect as
5756 starting GDB with the '-mapped' command-line option.
5758 You can cause GDB to read the entire symbol table immediately by using
5759 the '-readnow' option with any of the commands that load symbol table
5760 information (or on the GDB command line). This makes the command
5761 slower, but makes future operations faster.
5763 The -mapped and -readnow options are typically combined in order to
5764 build a `fred.syms' file that contains complete symbol information.
5765 A simple GDB invocation to do nothing but build a `.syms' file for future
5768 gdb -batch -nx -mapped -readnow programname
5770 The `.syms' file is specific to the host machine on which GDB is run.
5771 It holds an exact image of GDB's internal symbol table. It cannot be
5772 shared across multiple host platforms.
5774 * longjmp() handling
5776 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5777 siglongjmp() without losing control. This feature has not yet been ported to
5778 all systems. It currently works on many 386 platforms, all MIPS-based
5779 platforms (SGI, DECstation, etc), and Sun3/4.
5783 Preliminary work has been put in to support the new Solaris OS from Sun. At
5784 this time, it can control and debug processes, but it is not capable of
5789 As always, many many bug fixes. The major areas were with g++, and mipsread.
5790 People using the MIPS-based platforms should experience fewer mysterious
5791 crashes and trashed symbol tables.
5793 *** Changes in GDB-4.4:
5795 * New machines supported (host and target)
5797 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5799 BSD Reno on Vax vax-dec-bsd
5800 Ultrix on Vax vax-dec-ultrix
5802 * New machines supported (target)
5804 AMD 29000 embedded, using EBMON a29k-none-none
5808 GDB continues to improve its handling of C++. `References' work better.
5809 The demangler has also been improved, and now deals with symbols mangled as
5810 per the Annotated C++ Reference Guide.
5812 GDB also now handles `stabs' symbol information embedded in MIPS
5813 `ecoff' symbol tables. Since the ecoff format was not easily
5814 extensible to handle new languages such as C++, this appeared to be a
5815 good way to put C++ debugging info into MIPS binaries. This option
5816 will be supported in the GNU C compiler, version 2, when it is
5819 * New features for SVR4
5821 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5822 shared libraries. Debugging dynamically linked programs should present
5823 only minor differences from debugging statically linked programs.
5825 The `info proc' command will print out information about any process
5826 on an SVR4 system (including the one you are debugging). At the moment,
5827 it prints the address mappings of the process.
5829 If you bring up GDB on another SVR4 system, please send mail to
5830 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5832 * Better dynamic linking support in SunOS
5834 Reading symbols from shared libraries which contain debugging symbols
5835 now works properly. However, there remain issues such as automatic
5836 skipping of `transfer vector' code during function calls, which
5837 make it harder to debug code in a shared library, than to debug the
5838 same code linked statically.
5842 GDB is now using the latest `getopt' routines from the FSF. This
5843 version accepts the -- prefix for options with long names. GDB will
5844 continue to accept the old forms (-option and +option) as well.
5845 Various single letter abbreviations for options have been explicity
5846 added to the option table so that they won't get overshadowed in the
5847 future by other options that begin with the same letter.
5851 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5852 Many assorted bugs have been handled. Many more remain to be handled.
5853 See the various ChangeLog files (primarily in gdb and bfd) for details.
5856 *** Changes in GDB-4.3:
5858 * New machines supported (host and target)
5860 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5861 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5862 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5864 * Almost SCO Unix support
5866 We had hoped to support:
5867 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5868 (except for core file support), but we discovered very late in the release
5869 that it has problems with process groups that render gdb unusable. Sorry
5870 about that. I encourage people to fix it and post the fixes.
5872 * Preliminary ELF and DWARF support
5874 GDB can read ELF object files on System V Release 4, and can handle
5875 debugging records for C, in DWARF format, in ELF files. This support
5876 is preliminary. If you bring up GDB on another SVR4 system, please
5877 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5882 GDB now uses the latest `readline' library. One user-visible change
5883 is that two tabs will list possible command completions, which previously
5884 required typing M-? (meta-question mark, or ESC ?).
5888 The `stepi' bug that many of you noticed has been squashed.
5889 Many bugs in C++ have been handled. Many more remain to be handled.
5890 See the various ChangeLog files (primarily in gdb and bfd) for details.
5892 * State of the MIPS world (in case you wondered):
5894 GDB can understand the symbol tables emitted by the compilers
5895 supplied by most vendors of MIPS-based machines, including DEC. These
5896 symbol tables are in a format that essentially nobody else uses.
5898 Some versions of gcc come with an assembler post-processor called
5899 mips-tfile. This program is required if you want to do source-level
5900 debugging of gcc-compiled programs. I believe FSF does not ship
5901 mips-tfile with gcc version 1, but it will eventually come with gcc
5904 Debugging of g++ output remains a problem. g++ version 1.xx does not
5905 really support it at all. (If you're lucky, you should be able to get
5906 line numbers and stack traces to work, but no parameters or local
5907 variables.) With some work it should be possible to improve the
5910 When gcc version 2 is released, you will have somewhat better luck.
5911 However, even then you will get confusing results for inheritance and
5914 We will eventually provide full debugging of g++ output on
5915 DECstations. This will probably involve some kind of stabs-in-ecoff
5916 encapulation, but the details have not been worked out yet.
5919 *** Changes in GDB-4.2:
5921 * Improved configuration
5923 Only one copy of `configure' exists now, and it is not self-modifying.
5924 Porting BFD is simpler.
5928 The `step' and `next' commands now only stop at the first instruction
5929 of a source line. This prevents the multiple stops that used to occur
5930 in switch statements, for-loops, etc. `Step' continues to stop if a
5931 function that has debugging information is called within the line.
5935 Lots of small bugs fixed. More remain.
5937 * New host supported (not target)
5939 Intel 386 PC clone running Mach i386-none-mach
5942 *** Changes in GDB-4.1:
5944 * Multiple source language support
5946 GDB now has internal scaffolding to handle several source languages.
5947 It determines the type of each source file from its filename extension,
5948 and will switch expression parsing and number formatting to match the
5949 language of the function in the currently selected stack frame.
5950 You can also specifically set the language to be used, with
5951 `set language c' or `set language modula-2'.
5955 GDB now has preliminary support for the GNU Modula-2 compiler,
5956 currently under development at the State University of New York at
5957 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5958 continue through the fall of 1991 and into 1992.
5960 Other Modula-2 compilers are currently not supported, and attempting to
5961 debug programs compiled with them will likely result in an error as the
5962 symbol table is read. Feel free to work on it, though!
5964 There are hooks in GDB for strict type checking and range checking,
5965 in the `Modula-2 philosophy', but they do not currently work.
5969 GDB can now write to executable and core files (e.g. patch
5970 a variable's value). You must turn this switch on, specify
5971 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5972 by assigning a new value to a variable. Modifications take
5975 * Automatic SunOS shared library reading
5977 When you run your program, GDB automatically determines where its
5978 shared libraries (if any) have been loaded, and reads their symbols.
5979 The `share' command is no longer needed. This also works when
5980 examining core files.
5984 You can specify the number of lines that the `list' command shows.
5987 * New machines supported (host and target)
5989 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5990 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5991 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5993 * New hosts supported (not targets)
5995 IBM RT/PC: romp-ibm-aix or rtpc
5997 * New targets supported (not hosts)
5999 AMD 29000 embedded with COFF a29k-none-coff
6000 AMD 29000 embedded with a.out a29k-none-aout
6001 Ultracomputer remote kernel debug a29k-nyu-kern
6003 * New remote interfaces
6009 *** Changes in GDB-4.0:
6013 Wide output is wrapped at good places to make the output more readable.
6015 Gdb now supports cross-debugging from a host machine of one type to a
6016 target machine of another type. Communication with the target system
6017 is over serial lines. The ``target'' command handles connecting to the
6018 remote system; the ``load'' command will download a program into the
6019 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6020 also supports debugging of realtime processes running under VxWorks,
6021 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6022 stub on the target system.
6024 New CPUs supported include the AMD 29000 and Intel 960.
6026 GDB now reads object files and symbol tables via a ``binary file''
6027 library, which allows a single copy of GDB to debug programs of multiple
6028 object file types such as a.out and coff.
6030 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6031 refcard.dvi and refcard.ps are available to format it).
6034 * Control-Variable user interface simplified
6036 All variables that control the operation of the debugger can be set
6037 by the ``set'' command, and displayed by the ``show'' command.
6039 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6040 ``Show prompt'' produces the response:
6041 Gdb's prompt is new-gdb=>.
6043 What follows are the NEW set commands. The command ``help set'' will
6044 print a complete list of old and new set commands. ``help set FOO''
6045 will give a longer description of the variable FOO. ``show'' will show
6046 all of the variable descriptions and their current settings.
6048 confirm on/off: Enables warning questions for operations that are
6049 hard to recover from, e.g. rerunning the program while
6050 it is already running. Default is ON.
6052 editing on/off: Enables EMACS style command line editing
6053 of input. Previous lines can be recalled with
6054 control-P, the current line can be edited with control-B,
6055 you can search for commands with control-R, etc.
6058 history filename NAME: NAME is where the gdb command history
6059 will be stored. The default is .gdb_history,
6060 or the value of the environment variable
6063 history size N: The size, in commands, of the command history. The
6064 default is 256, or the value of the environment variable
6067 history save on/off: If this value is set to ON, the history file will
6068 be saved after exiting gdb. If set to OFF, the
6069 file will not be saved. The default is OFF.
6071 history expansion on/off: If this value is set to ON, then csh-like
6072 history expansion will be performed on
6073 command line input. The default is OFF.
6075 radix N: Sets the default radix for input and output. It can be set
6076 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6077 in the current radix, so "set radix 10" is always a no-op.
6079 height N: This integer value is the number of lines on a page. Default
6080 is 24, the current `stty rows'' setting, or the ``li#''
6081 setting from the termcap entry matching the environment
6084 width N: This integer value is the number of characters on a line.
6085 Default is 80, the current `stty cols'' setting, or the ``co#''
6086 setting from the termcap entry matching the environment
6089 Note: ``set screensize'' is obsolete. Use ``set height'' and
6090 ``set width'' instead.
6092 print address on/off: Print memory addresses in various command displays,
6093 such as stack traces and structure values. Gdb looks
6094 more ``symbolic'' if you turn this off; it looks more
6095 ``machine level'' with it on. Default is ON.
6097 print array on/off: Prettyprint arrays. New convenient format! Default
6100 print demangle on/off: Print C++ symbols in "source" form if on,
6103 print asm-demangle on/off: Same, for assembler level printouts
6106 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6109 * Support for Epoch Environment.
6111 The epoch environment is a version of Emacs v18 with windowing. One
6112 new command, ``inspect'', is identical to ``print'', except that if you
6113 are running in the epoch environment, the value is printed in its own
6117 * Support for Shared Libraries
6119 GDB can now debug programs and core files that use SunOS shared libraries.
6120 Symbols from a shared library cannot be referenced
6121 before the shared library has been linked with the program (this
6122 happens after you type ``run'' and before the function main() is entered).
6123 At any time after this linking (including when examining core files
6124 from dynamically linked programs), gdb reads the symbols from each
6125 shared library when you type the ``sharedlibrary'' command.
6126 It can be abbreviated ``share''.
6128 sharedlibrary REGEXP: Load shared object library symbols for files
6129 matching a unix regular expression. No argument
6130 indicates to load symbols for all shared libraries.
6132 info sharedlibrary: Status of loaded shared libraries.
6137 A watchpoint stops execution of a program whenever the value of an
6138 expression changes. Checking for this slows down execution
6139 tremendously whenever you are in the scope of the expression, but is
6140 quite useful for catching tough ``bit-spreader'' or pointer misuse
6141 problems. Some machines such as the 386 have hardware for doing this
6142 more quickly, and future versions of gdb will use this hardware.
6144 watch EXP: Set a watchpoint (breakpoint) for an expression.
6146 info watchpoints: Information about your watchpoints.
6148 delete N: Deletes watchpoint number N (same as breakpoints).
6149 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6150 enable N: Re-enables watchpoint number N (same as breakpoints).
6153 * C++ multiple inheritance
6155 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6158 * C++ exception handling
6160 Gdb now supports limited C++ exception handling. Besides the existing
6161 ability to breakpoint on an exception handler, gdb can breakpoint on
6162 the raising of an exception (before the stack is peeled back to the
6165 catch FOO: If there is a FOO exception handler in the dynamic scope,
6166 set a breakpoint to catch exceptions which may be raised there.
6167 Multiple exceptions (``catch foo bar baz'') may be caught.
6169 info catch: Lists all exceptions which may be caught in the
6170 current stack frame.
6173 * Minor command changes
6175 The command ``call func (arg, arg, ...)'' now acts like the print
6176 command, except it does not print or save a value if the function's result
6177 is void. This is similar to dbx usage.
6179 The ``up'' and ``down'' commands now always print the frame they end up
6180 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6181 frames without printing.
6183 * New directory command
6185 'dir' now adds directories to the FRONT of the source search path.
6186 The path starts off empty. Source files that contain debug information
6187 about the directory in which they were compiled can be found even
6188 with an empty path; Sun CC and GCC include this information. If GDB can't
6189 find your source file in the current directory, type "dir .".
6191 * Configuring GDB for compilation
6193 For normal use, type ``./configure host''. See README or gdb.texinfo
6196 GDB now handles cross debugging. If you are remotely debugging between
6197 two different machines, type ``./configure host -target=targ''.
6198 Host is the machine where GDB will run; targ is the machine
6199 where the program that you are debugging will run.