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 * GDB now allows users to specify explicit locations, bypassing
12 the linespec parser. This feature is also available to GDB/MI
15 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
16 GDB now is able to debug both AArch64 applications and ARM applications
21 maint set target-non-stop (on|off|auto)
22 maint show target-non-stop
23 Control whether GDB targets always operate in non-stop mode even if
24 "set non-stop" is "off". The default is "auto", meaning non-stop
25 mode is enabled if supported by the target.
28 maint show bfd-sharing
29 Control the reuse of bfd objects.
33 Control display of debugging info regarding bfd caching.
35 set remote multiprocess-extensions-packet
36 show remote multiprocess-extensions-packet
37 Set/show the use of the remote protocol multiprocess extensions.
39 * The "disassemble" command accepts a new modifier: /s.
40 It prints mixed source+disassembly like /m with two differences:
41 - disassembled instructions are now printed in program order, and
42 - and source for all relevant files is now printed.
43 The "/m" option is now considered deprecated: its "source-centric"
44 output hasn't proved useful in practice.
46 * Support for various ROM monitors has been removed:
48 target dbug dBUG ROM monitor for Motorola ColdFire
49 target picobug Motorola picobug monitor
50 target dink32 DINK32 ROM monitor for PowerPC
51 target m32r Renesas M32R/D ROM monitor
52 target mon2000 mon2000 ROM monitor
53 target ppcbug PPCBUG ROM monitor for PowerPC
55 * Support for reading/writing memory and extracting values on architectures
56 whose memory is addressable in units of any integral multiple of 8 bits.
61 Indicates that an exec system call was executed.
63 exec-events feature in qSupported
64 The qSupported packet allows GDB to request support for exec
65 events using the new 'gdbfeature' exec-event, and the qSupported
66 response can contain the corresponding 'stubfeature'. Set and
67 show commands can be used to display whether these features are enabled.
69 * Extended-remote exec events
71 ** GDB now has support for exec events on extended-remote Linux targets.
72 For such targets with Linux kernels 2.5.46 and later, this enables
73 follow-exec-mode and exec catchpoints.
75 set remote exec-event-feature-packet
76 show remote exec-event-feature-packet
77 Set/show the use of the remote exec event feature.
79 *** Changes in GDB 7.10
81 * Support for process record-replay and reverse debugging on aarch64*-linux*
82 targets has been added. GDB now supports recording of A64 instruction set
83 including advance SIMD instructions.
85 * Support for Sun's version of the "stabs" debug file format has been removed.
87 * GDB now honors the content of the file /proc/PID/coredump_filter
88 (PID is the process ID) on GNU/Linux systems. This file can be used
89 to specify the types of memory mappings that will be included in a
90 corefile. For more information, please refer to the manual page of
91 "core(5)". GDB also has a new command: "set use-coredump-filter
92 on|off". It allows to set whether GDB will read the content of the
93 /proc/PID/coredump_filter file when generating a corefile.
95 * The "info os" command on GNU/Linux can now display information on
97 "info os cpus" Listing of all cpus/cores on the system
99 * GDB has two new commands: "set serial parity odd|even|none" and
100 "show serial parity". These allows to set or show parity for the
103 * The "info source" command now displays the producer string if it was
104 present in the debug info. This typically includes the compiler version
105 and may include things like its command line arguments.
107 * The "info dll", an alias of the "info sharedlibrary" command,
108 is now available on all platforms.
110 * Directory names supplied to the "set sysroot" commands may be
111 prefixed with "target:" to tell GDB to access shared libraries from
112 the target system, be it local or remote. This replaces the prefix
113 "remote:". The default sysroot has been changed from "" to
114 "target:". "remote:" is automatically converted to "target:" for
115 backward compatibility.
117 * The system root specified by "set sysroot" will be prepended to the
118 filename of the main executable (if reported to GDB as absolute by
119 the operating system) when starting processes remotely, and when
120 attaching to already-running local or remote processes.
122 * GDB now supports automatic location and retrieval of executable
123 files from remote targets. Remote debugging can now be initiated
124 using only a "target remote" or "target extended-remote" command
125 (no "set sysroot" or "file" commands are required). See "New remote
128 * The "dump" command now supports verilog hex format.
130 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
132 * On GNU/Linux, GDB and gdbserver are now able to access executable
133 and shared library files without a "set sysroot" command when
134 attaching to processes running in different mount namespaces from
135 the debugger. This makes it possible to attach to processes in
136 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
137 See "New remote packets" below.
139 * The "tui reg" command now provides completion for all of the
140 available register groups, including target specific groups.
142 * The HISTSIZE environment variable is no longer read when determining
143 the size of GDB's command history. GDB now instead reads the dedicated
144 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
145 disables truncation of command history. Non-numeric values of GDBHISTSIZE
150 ** Memory ports can now be unbuffered.
154 ** gdb.Objfile objects have a new attribute "username",
155 which is the name of the objfile as specified by the user,
156 without, for example, resolving symlinks.
157 ** You can now write frame unwinders in Python.
158 ** gdb.Type objects have a new method "optimized_out",
159 returning optimized out gdb.Value instance of this type.
160 ** gdb.Value objects have new methods "reference_value" and
161 "const_value" which return a reference to the value and a
162 "const" version of the value respectively.
166 maint print symbol-cache
167 Print the contents of the symbol cache.
169 maint print symbol-cache-statistics
170 Print statistics of symbol cache usage.
172 maint flush-symbol-cache
173 Flush the contents of the symbol cache.
177 Start branch trace recording using Branch Trace Store (BTS) format.
180 Evaluate expression by using the compiler and print result.
184 Explicit commands for enabling and disabling tui mode.
187 set mpx bound on i386 and amd64
188 Support for bound table investigation on Intel(R) MPX enabled applications.
192 Start branch trace recording using Intel(R) Processor Trace format.
195 Print information about branch tracing internals.
197 maint btrace packet-history
198 Print the raw branch tracing data.
200 maint btrace clear-packet-history
201 Discard the stored raw branch tracing data.
204 Discard all branch tracing data. It will be fetched and processed
205 anew by the next "record" command.
210 Renamed from "set debug dwarf2-die".
212 Renamed from "show debug dwarf2-die".
215 Renamed from "set debug dwarf2-read".
216 show debug dwarf-read
217 Renamed from "show debug dwarf2-read".
219 maint set dwarf always-disassemble
220 Renamed from "maint set dwarf2 always-disassemble".
221 maint show dwarf always-disassemble
222 Renamed from "maint show dwarf2 always-disassemble".
224 maint set dwarf max-cache-age
225 Renamed from "maint set dwarf2 max-cache-age".
226 maint show dwarf max-cache-age
227 Renamed from "maint show dwarf2 max-cache-age".
230 show debug dwarf-line
231 Control display of debugging info regarding DWARF line processing.
235 Set the maximum number of candidates to be considered during
236 completion. The default value is 200. This limit allows GDB
237 to avoid generating large completion lists, the computation of
238 which can cause the debugger to become temporarily unresponsive.
240 set history remove-duplicates
241 show history remove-duplicates
242 Control the removal of duplicate history entries.
244 maint set symbol-cache-size
245 maint show symbol-cache-size
246 Control the size of the symbol cache.
248 set|show record btrace bts buffer-size
249 Set and show the size of the ring buffer used for branch tracing in
251 The obtained size may differ from the requested size. Use "info
252 record" to see the obtained buffer size.
254 set debug linux-namespaces
255 show debug linux-namespaces
256 Control display of debugging info regarding Linux namespaces.
258 set|show record btrace pt buffer-size
259 Set and show the size of the ring buffer used for branch tracing in
260 Intel(R) Processor Trace format.
261 The obtained size may differ from the requested size. Use "info
262 record" to see the obtained buffer size.
264 maint set|show btrace pt skip-pad
265 Set and show whether PAD packets are skipped when computing the
268 * The command 'thread apply all' can now support new option '-ascending'
269 to call its specified command for all threads in ascending order.
271 * Python/Guile scripting
273 ** GDB now supports auto-loading of Python/Guile scripts contained in the
274 special section named `.debug_gdb_scripts'.
278 qXfer:btrace-conf:read
279 Return the branch trace configuration for the current thread.
281 Qbtrace-conf:bts:size
282 Set the requested ring buffer size for branch tracing in BTS format.
285 Enable Intel(R) Procesor Trace-based branch tracing for the current
286 process. The remote stub reports support for this packet to GDB's
290 Set the requested ring buffer size for branch tracing in Intel(R) Processor
294 Indicates a memory breakpoint instruction was executed, irrespective
295 of whether it was GDB that planted the breakpoint or the breakpoint
296 is hardcoded in the program. This is required for correct non-stop
300 Indicates the target stopped for a hardware breakpoint. This is
301 required for correct non-stop mode operation.
304 Return information about files on the remote system.
307 Return the full absolute name of the file that was executed to
308 create a process running on the remote system.
311 Select the filesystem on which vFile: operations with filename
312 arguments will operate. This is required for GDB to be able to
313 access files on remote targets where the remote stub does not
314 share a common filesystem with the inferior(s).
317 Indicates that a fork system call was executed.
320 Indicates that a vfork system call was executed.
322 vforkdone stop reason
323 Indicates that a vfork child of the specified process has executed
324 an exec or exit, allowing the vfork parent to resume execution.
326 fork-events and vfork-events features in qSupported
327 The qSupported packet allows GDB to request support for fork and
328 vfork events using new 'gdbfeatures' fork-events and vfork-events,
329 and the qSupported response can contain the corresponding
330 'stubfeatures'. Set and show commands can be used to display
331 whether these features are enabled.
333 * Extended-remote fork events
335 ** GDB now has support for fork events on extended-remote Linux
336 targets. For targets with Linux kernels 2.5.60 and later, this
337 enables follow-fork-mode and detach-on-fork for both fork and
338 vfork, as well as fork and vfork catchpoints.
340 * The info record command now shows the recording format and the
341 branch tracing configuration for the current thread when using
342 the btrace record target.
343 For the BTS format, it shows the ring buffer size.
345 * GDB now has support for DTrace USDT (Userland Static Defined
346 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
348 * GDB now supports access to vector registers on S/390 GNU/Linux
351 * Removed command line options
353 -xdb HP-UX XDB compatibility mode.
355 * Removed targets and native configurations
357 HP/PA running HP-UX hppa*-*-hpux*
358 Itanium running HP-UX ia64-*-hpux*
360 * New configure options
363 This configure option allows the user to build GDB with support for
364 Intel(R) Processor Trace (default: auto). This requires libipt.
366 --with-libipt-prefix=PATH
367 Specify the path to the version of libipt that GDB should use.
368 $PATH/include should contain the intel-pt.h header and
369 $PATH/lib should contain the libipt.so library.
371 *** Changes in GDB 7.9.1
375 ** Xmethods can now specify a result type.
377 *** Changes in GDB 7.9
379 * GDB now supports hardware watchpoints on x86 GNU Hurd.
383 ** You can now access frame registers from Python scripts.
384 ** New attribute 'producer' for gdb.Symtab objects.
385 ** gdb.Objfile objects have a new attribute "progspace",
386 which is the gdb.Progspace object of the containing program space.
387 ** gdb.Objfile objects have a new attribute "owner".
388 ** gdb.Objfile objects have a new attribute "build_id",
389 which is the build ID generated when the file was built.
390 ** gdb.Objfile objects have a new method "add_separate_debug_file".
391 ** A new event "gdb.clear_objfiles" has been added, triggered when
392 selecting a new file to debug.
393 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
394 ** New function gdb.lookup_objfile.
396 New events which are triggered when GDB modifies the state of the
399 ** gdb.events.inferior_call_pre: Function call is about to be made.
400 ** gdb.events.inferior_call_post: Function call has just been made.
401 ** gdb.events.memory_changed: A memory location has been altered.
402 ** gdb.events.register_changed: A register has been altered.
404 * New Python-based convenience functions:
406 ** $_caller_is(name [, number_of_frames])
407 ** $_caller_matches(regexp [, number_of_frames])
408 ** $_any_caller_is(name [, number_of_frames])
409 ** $_any_caller_matches(regexp [, number_of_frames])
411 * GDB now supports the compilation and injection of source code into
412 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
413 to compile the source code to object code, and if successful, inject
414 and execute that code within the current context of the inferior.
415 Currently the C language is supported. The commands used to
416 interface with this new feature are:
418 compile code [-raw|-r] [--] [source code]
419 compile file [-raw|-r] filename
423 demangle [-l language] [--] name
424 Demangle "name" in the specified language, or the current language
425 if elided. This command is renamed from the "maint demangle" command.
426 The latter is kept as a no-op to avoid "maint demangle" being interpreted
427 as "maint demangler-warning".
429 queue-signal signal-name-or-number
430 Queue a signal to be delivered to the thread when it is resumed.
432 add-auto-load-scripts-directory directory
433 Add entries to the list of directories from which to load auto-loaded
436 maint print user-registers
437 List all currently available "user" registers.
439 compile code [-r|-raw] [--] [source code]
440 Compile, inject, and execute in the inferior the executable object
441 code produced by compiling the provided source code.
443 compile file [-r|-raw] filename
444 Compile and inject into the inferior the executable object code
445 produced by compiling the source code stored in the filename
448 * On resume, GDB now always passes the signal the program had stopped
449 for to the thread the signal was sent to, even if the user changed
450 threads before resuming. Previously GDB would often (but not
451 always) deliver the signal to the thread that happens to be current
454 * Conversely, the "signal" command now consistently delivers the
455 requested signal to the current thread. GDB now asks for
456 confirmation if the program had stopped for a signal and the user
457 switched threads meanwhile.
459 * "breakpoint always-inserted" modes "off" and "auto" merged.
461 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
462 won't remove breakpoints from the target until all threads stop,
463 even in non-stop mode. The "auto" mode has been removed, and "off"
464 is now the default mode.
468 set debug symbol-lookup
469 show debug symbol-lookup
470 Control display of debugging info regarding symbol lookup.
474 ** The -list-thread-groups command outputs an exit-code field for
475 inferiors that have exited.
479 MIPS SDE mips*-sde*-elf*
483 Support for these obsolete configurations has been removed.
485 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
486 SGI Irix-5.x mips-*-irix5*
487 SGI Irix-6.x mips-*-irix6*
488 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
489 VAX running Ultrix vax-*-ultrix*
491 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
492 and "assf"), have been removed. Use the "sharedlibrary" command, or
493 its alias "share", instead.
495 *** Changes in GDB 7.8
497 * New command line options
500 This is an alias for the --data-directory option.
502 * GDB supports printing and modifying of variable length automatic arrays
503 as specified in ISO C99.
505 * The ARM simulator now supports instruction level tracing
506 with or without disassembly.
510 GDB now has support for scripting using Guile. Whether this is
511 available is determined at configure time.
512 Guile version 2.0 or greater is required.
513 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
515 * New commands (for set/show, see "New options" below)
519 Invoke CODE by passing it to the Guile interpreter.
523 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
525 info auto-load guile-scripts [regexp]
526 Print the list of automatically loaded Guile scripts.
528 * The source command is now capable of sourcing Guile scripts.
529 This feature is dependent on the debugger being built with Guile support.
533 set print symbol-loading (off|brief|full)
534 show print symbol-loading
535 Control whether to print informational messages when loading symbol
536 information for a file. The default is "full", but when debugging
537 programs with large numbers of shared libraries the amount of output
540 set guile print-stack (none|message|full)
541 show guile print-stack
542 Show a stack trace when an error is encountered in a Guile script.
544 set auto-load guile-scripts (on|off)
545 show auto-load guile-scripts
546 Control auto-loading of Guile script files.
548 maint ada set ignore-descriptive-types (on|off)
549 maint ada show ignore-descriptive-types
550 Control whether the debugger should ignore descriptive types in Ada
551 programs. The default is not to ignore the descriptive types. See
552 the user manual for more details on descriptive types and the intended
553 usage of this option.
555 set auto-connect-native-target
557 Control whether GDB is allowed to automatically connect to the
558 native target for the run, attach, etc. commands when not connected
559 to any target yet. See also "target native" below.
561 set record btrace replay-memory-access (read-only|read-write)
562 show record btrace replay-memory-access
563 Control what memory accesses are allowed during replay.
565 maint set target-async (on|off)
566 maint show target-async
567 This controls whether GDB targets operate in synchronous or
568 asynchronous mode. Normally the default is asynchronous, if it is
569 available; but this can be changed to more easily debug problems
570 occurring only in synchronous mode.
572 set mi-async (on|off)
574 Control whether MI asynchronous mode is preferred. This supersedes
575 "set target-async" of previous GDB versions.
577 * "set target-async" is deprecated as a CLI option and is now an alias
578 for "set mi-async" (only puts MI into async mode).
580 * Background execution commands (e.g., "c&", "s&", etc.) are now
581 possible ``out of the box'' if the target supports them. Previously
582 the user would need to explicitly enable the possibility with the
583 "set target-async on" command.
585 * New features in the GDB remote stub, GDBserver
587 ** New option --debug-format=option1[,option2,...] allows one to add
588 additional text to each output. At present only timestamps
589 are supported: --debug-format=timestamps.
590 Timestamps can also be turned on with the
591 "monitor set debug-format timestamps" command from GDB.
593 * The 'record instruction-history' command now starts counting instructions
594 at one. This also affects the instruction ranges reported by the
595 'record function-call-history' command when given the /i modifier.
597 * The command 'record function-call-history' supports a new modifier '/c' to
598 indent the function names based on their call stack depth.
599 The fields for the '/i' and '/l' modifier have been reordered.
600 The source line range is now prefixed with 'at'.
601 The instruction range is now prefixed with 'inst'.
602 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
603 "record instruction-history" and "list" commands.
605 * The ranges given as arguments to the 'record function-call-history' and
606 'record instruction-history' commands are now inclusive.
608 * The btrace record target now supports the 'record goto' command.
609 For locations inside the execution trace, the back trace is computed
610 based on the information stored in the execution trace.
612 * The btrace record target supports limited reverse execution and replay.
613 The target does not record data and therefore does not allow reading
616 * The "catch syscall" command now works on s390*-linux* targets.
618 * The "compare-sections" command is no longer specific to target
619 remote. It now works with all targets.
621 * All native targets are now consistently called "native".
622 Consequently, the "target child", "target GNU", "target djgpp",
623 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
624 commands have been replaced with "target native". The QNX/NTO port
625 leaves the "procfs" target in place and adds a "native" target for
626 consistency with other ports. The impact on users should be minimal
627 as these commands previously either throwed an error, or were
628 no-ops. The target's name is visible in the output of the following
629 commands: "help target", "info target", "info files", "maint print
632 * The "target native" command now connects to the native target. This
633 can be used to launch native programs even when "set
634 auto-connect-native-target" is set to off.
636 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
638 * Support for Intel(R) AVX-512 registers on GNU/Linux.
639 Support displaying and modifying Intel(R) AVX-512 registers
640 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
644 qXfer:btrace:read's annex
645 The qXfer:btrace:read packet supports a new annex 'delta' to read
646 branch trace incrementally.
650 ** Valid Python operations on gdb.Value objects representing
651 structs/classes invoke the corresponding overloaded operators if
653 ** New `Xmethods' feature in the Python API. Xmethods are
654 additional methods or replacements for existing methods of a C++
655 class. This feature is useful for those cases where a method
656 defined in C++ source code could be inlined or optimized out by
657 the compiler, making it unavailable to GDB.
660 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
662 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
663 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
664 its alias "share", instead.
666 * The commands "set remotebaud" and "show remotebaud" are no longer
667 supported. Use "set serial baud" and "show serial baud" (respectively)
672 ** A new option "-gdb-set mi-async" replaces "-gdb-set
673 target-async". The latter is left as a deprecated alias of the
674 former for backward compatibility. If the target supports it,
675 CLI background execution commands are now always possible by
676 default, independently of whether the frontend stated a
677 preference for asynchronous execution with "-gdb-set mi-async".
678 Previously "-gdb-set target-async off" affected both MI execution
679 commands and CLI execution commands.
681 *** Changes in GDB 7.7
683 * Improved support for process record-replay and reverse debugging on
684 arm*-linux* targets. Support for thumb32 and syscall instruction
685 recording has been added.
687 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
689 * GDB now supports Fission DWP file format version 2.
690 http://gcc.gnu.org/wiki/DebugFission
692 * New convenience function "$_isvoid", to check whether an expression
693 is void. A void expression is an expression where the type of the
694 result is "void". For example, some convenience variables may be
695 "void" when evaluated (e.g., "$_exitcode" before the execution of
696 the program being debugged; or an undefined convenience variable).
697 Another example, when calling a function whose return type is
700 * The "maintenance print objfiles" command now takes an optional regexp.
702 * The "catch syscall" command now works on arm*-linux* targets.
704 * GDB now consistently shows "<not saved>" when printing values of
705 registers the debug info indicates have not been saved in the frame
706 and there's nowhere to retrieve them from
707 (callee-saved/call-clobbered registers):
712 (gdb) info registers rax
715 Before, the former would print "<optimized out>", and the latter
716 "*value not available*".
718 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
723 ** Frame filters and frame decorators have been added.
724 ** Temporary breakpoints are now supported.
725 ** Line tables representation has been added.
726 ** New attribute 'parent_type' for gdb.Field objects.
727 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
728 ** New attribute 'name' for gdb.Type objects.
732 Nios II ELF nios2*-*-elf
733 Nios II GNU/Linux nios2*-*-linux
734 Texas Instruments MSP430 msp430*-*-elf
736 * Removed native configurations
738 Support for these a.out NetBSD and OpenBSD obsolete configurations has
739 been removed. ELF variants of these configurations are kept supported.
741 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
742 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
743 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
744 i[34567]86-*-openbsd3.[0-3]
745 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
746 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
747 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
751 Like "catch throw", but catches a re-thrown exception.
753 Renamed from old "maint check-symtabs".
755 Perform consistency checks on symtabs.
757 Expand symtabs matching an optional regexp.
760 Display the details of GDB configure-time options.
762 maint set|show per-command
763 maint set|show per-command space
764 maint set|show per-command time
765 maint set|show per-command symtab
766 Enable display of per-command gdb resource usage.
768 remove-symbol-file FILENAME
769 remove-symbol-file -a ADDRESS
770 Remove a symbol file added via add-symbol-file. The file to remove
771 can be identified by its filename or by an address that lies within
772 the boundaries of this symbol file in memory.
775 info exceptions REGEXP
776 Display the list of Ada exceptions defined in the program being
777 debugged. If provided, only the exceptions whose names match REGEXP
782 set debug symfile off|on
784 Control display of debugging info regarding reading symbol files and
785 symbol tables within those files
787 set print raw frame-arguments
788 show print raw frame-arguments
789 Set/show whether to print frame arguments in raw mode,
790 disregarding any defined pretty-printers.
792 set remote trace-status-packet
793 show remote trace-status-packet
794 Set/show the use of remote protocol qTStatus packet.
798 Control display of debugging messages related to Nios II targets.
802 Control whether target-assisted range stepping is enabled.
804 set startup-with-shell
805 show startup-with-shell
806 Specifies whether Unix child processes are started via a shell or
811 Use the target memory cache for accesses to the code segment. This
812 improves performance of remote debugging (particularly disassembly).
814 * You can now use a literal value 'unlimited' for options that
815 interpret 0 or -1 as meaning "unlimited". E.g., "set
816 trace-buffer-size unlimited" is now an alias for "set
817 trace-buffer-size -1" and "set height unlimited" is now an alias for
820 * The "set debug symtab-create" debugging option of GDB has been changed to
821 accept a verbosity level. 0 means "off", 1 provides basic debugging
822 output, and values of 2 or greater provides more verbose output.
824 * New command-line options
826 Display the details of GDB configure-time options.
828 * The command 'tsave' can now support new option '-ctf' to save trace
829 buffer in Common Trace Format.
831 * Newly installed $prefix/bin/gcore acts as a shell interface for the
834 * GDB now implements the the C++ 'typeid' operator.
836 * The new convenience variable $_exception holds the exception being
837 thrown or caught at an exception-related catchpoint.
839 * The exception-related catchpoints, like "catch throw", now accept a
840 regular expression which can be used to filter exceptions by type.
842 * The new convenience variable $_exitsignal is automatically set to
843 the terminating signal number when the program being debugged dies
844 due to an uncaught signal.
848 ** All MI commands now accept an optional "--language" option.
849 Support for this feature can be verified by using the "-list-features"
850 command, which should contain "language-option".
852 ** The new command -info-gdb-mi-command allows the user to determine
853 whether a GDB/MI command is supported or not.
855 ** The "^error" result record returned when trying to execute an undefined
856 GDB/MI command now provides a variable named "code" whose content is the
857 "undefined-command" error code. Support for this feature can be verified
858 by using the "-list-features" command, which should contain
859 "undefined-command-error-code".
861 ** The -trace-save MI command can optionally save trace buffer in Common
864 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
866 ** The command -data-list-register-values now accepts an optional
867 "--skip-unavailable" option. When used, only the available registers
870 ** The new command -trace-frame-collected dumps collected variables,
871 computed expressions, tvars, memory and registers in a traceframe.
873 ** The commands -stack-list-locals, -stack-list-arguments and
874 -stack-list-variables now accept an option "--skip-unavailable".
875 When used, only the available locals or arguments are displayed.
877 ** The -exec-run command now accepts an optional "--start" option.
878 When used, the command follows the same semantics as the "start"
879 command, stopping the program's execution at the start of its
880 main subprogram. Support for this feature can be verified using
881 the "-list-features" command, which should contain
882 "exec-run-start-option".
884 ** The new commands -catch-assert and -catch-exceptions insert
885 catchpoints stopping the program when Ada exceptions are raised.
887 ** The new command -info-ada-exceptions provides the equivalent of
888 the new "info exceptions" command.
890 * New system-wide configuration scripts
891 A GDB installation now provides scripts suitable for use as system-wide
892 configuration scripts for the following systems:
896 * GDB now supports target-assigned range stepping with remote targets.
897 This improves the performance of stepping source lines by reducing
898 the number of control packets from/to GDB. See "New remote packets"
901 * GDB now understands the element 'tvar' in the XML traceframe info.
902 It has the id of the collected trace state variables.
904 * On S/390 targets that provide the transactional-execution feature,
905 the program interruption transaction diagnostic block (TDB) is now
906 represented as a number of additional "registers" in GDB.
912 The vCont packet supports a new 'r' action, that tells the remote
913 stub to step through an address range itself, without GDB
914 involvemement at each single-step.
916 qXfer:libraries-svr4:read's annex
917 The previously unused annex of the qXfer:libraries-svr4:read packet
918 is now used to support passing an argument list. The remote stub
919 reports support for this argument list to GDB's qSupported query.
920 The defined arguments are "start" and "prev", used to reduce work
921 necessary for library list updating, resulting in significant
924 * New features in the GDB remote stub, GDBserver
926 ** GDBserver now supports target-assisted range stepping. Currently
927 enabled on x86/x86_64 GNU/Linux targets.
929 ** GDBserver now adds element 'tvar' in the XML in the reply to
930 'qXfer:traceframe-info:read'. It has the id of the collected
931 trace state variables.
933 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
936 * New 'z' formatter for printing and examining memory, this displays the
937 value as hexadecimal zero padded on the left to the size of the type.
939 * GDB can now use Windows x64 unwinding data.
941 * The "set remotebaud" command has been replaced by "set serial baud".
942 Similarly, "show remotebaud" has been replaced by "show serial baud".
943 The "set remotebaud" and "show remotebaud" commands are still available
944 to provide backward compatibility with older versions of GDB.
946 *** Changes in GDB 7.6
948 * Target record has been renamed to record-full.
949 Record/replay is now enabled with the "record full" command.
950 This also affects settings that are associated with full record/replay
951 that have been moved from "set/show record" to "set/show record full":
953 set|show record full insn-number-max
954 set|show record full stop-at-limit
955 set|show record full memory-query
957 * A new record target "record-btrace" has been added. The new target
958 uses hardware support to record the control-flow of a process. It
959 does not support replaying the execution, but it implements the
960 below new commands for investigating the recorded execution log.
961 This new recording method can be enabled using:
965 The "record-btrace" target is only available on Intel Atom processors
966 and requires a Linux kernel 2.6.32 or later.
968 * Two new commands have been added for record/replay to give information
969 about the recorded execution without having to replay the execution.
970 The commands are only supported by "record btrace".
972 record instruction-history prints the execution history at
973 instruction granularity
975 record function-call-history prints the execution history at
978 * New native configurations
980 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
981 FreeBSD/powerpc powerpc*-*-freebsd
982 x86_64/Cygwin x86_64-*-cygwin*
983 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
987 ARM AArch64 aarch64*-*-elf
988 ARM AArch64 GNU/Linux aarch64*-*-linux
989 Lynx 178 PowerPC powerpc-*-lynx*178
990 x86_64/Cygwin x86_64-*-cygwin*
991 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
993 * If the configured location of system.gdbinit file (as given by the
994 --with-system-gdbinit option at configure time) is in the
995 data-directory (as specified by --with-gdb-datadir at configure
996 time) or in one of its subdirectories, then GDB will look for the
997 system-wide init file in the directory specified by the
998 --data-directory command-line option.
1000 * New command line options:
1002 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1003 other initialization files, unlike -nx which disables all of them.
1005 * Removed command line options
1007 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1010 * The 'ptype' and 'whatis' commands now accept an argument to control
1013 * 'info proc' now works on some core files.
1017 ** Vectors can be created with gdb.Type.vector.
1019 ** Python's atexit.register now works in GDB.
1021 ** Types can be pretty-printed via a Python API.
1023 ** Python 3 is now supported (in addition to Python 2.4 or later)
1025 ** New class gdb.Architecture exposes GDB's internal representation
1026 of architecture in the Python API.
1028 ** New method Frame.architecture returns the gdb.Architecture object
1029 corresponding to the frame's architecture.
1031 * New Python-based convenience functions:
1033 ** $_memeq(buf1, buf2, length)
1034 ** $_streq(str1, str2)
1036 ** $_regex(str, regex)
1038 * The 'cd' command now defaults to using '~' (the home directory) if not
1041 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1042 default for GCC since November 2000.
1044 * The command 'forward-search' can now be abbreviated as 'fo'.
1046 * The command 'info tracepoints' can now display 'installed on target'
1047 or 'not installed on target' for each non-pending location of tracepoint.
1049 * New configure options
1051 --enable-libmcheck/--disable-libmcheck
1052 By default, development versions are built with -lmcheck on hosts
1053 that support it, in order to help track memory corruption issues.
1054 Release versions, on the other hand, are built without -lmcheck
1055 by default. The --enable-libmcheck/--disable-libmcheck configure
1056 options allow the user to override that default.
1057 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1058 This configure option allows the user to build GDB with
1059 libbabeltrace using which GDB can read Common Trace Format data.
1061 * New commands (for set/show, see "New options" below)
1064 Catch signals. This is similar to "handle", but allows commands and
1065 conditions to be attached.
1068 List the BFDs known to GDB.
1070 python-interactive [command]
1072 Start a Python interactive prompt, or evaluate the optional command
1073 and print the result of expressions.
1076 "py" is a new alias for "python".
1078 enable type-printer [name]...
1079 disable type-printer [name]...
1080 Enable or disable type printers.
1084 ** For the Renesas Super-H architecture, the "regs" command has been removed
1085 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1090 set print type methods (on|off)
1091 show print type methods
1092 Control whether method declarations are displayed by "ptype".
1093 The default is to show them.
1095 set print type typedefs (on|off)
1096 show print type typedefs
1097 Control whether typedef definitions are displayed by "ptype".
1098 The default is to show them.
1100 set filename-display basename|relative|absolute
1101 show filename-display
1102 Control the way in which filenames is displayed.
1103 The default is "relative", which preserves previous behavior.
1105 set trace-buffer-size
1106 show trace-buffer-size
1107 Request target to change the size of trace buffer.
1109 set remote trace-buffer-size-packet auto|on|off
1110 show remote trace-buffer-size-packet
1111 Control the use of the remote protocol `QTBuffer:size' packet.
1115 Control display of debugging messages related to ARM AArch64.
1118 set debug coff-pe-read
1119 show debug coff-pe-read
1120 Control display of debugging messages related to reading of COFF/PE
1125 Control display of debugging messages related to Mach-O symbols
1128 set debug notification
1129 show debug notification
1130 Control display of debugging info for async remote notification.
1134 ** Command parameter changes are now notified using new async record
1135 "=cmd-param-changed".
1136 ** Trace frame changes caused by command "tfind" are now notified using
1137 new async record "=traceframe-changed".
1138 ** The creation, deletion and modification of trace state variables
1139 are now notified using new async records "=tsv-created",
1140 "=tsv-deleted" and "=tsv-modified".
1141 ** The start and stop of process record are now notified using new
1142 async record "=record-started" and "=record-stopped".
1143 ** Memory changes are now notified using new async record
1145 ** The data-disassemble command response will include a "fullname" field
1146 containing the absolute file name when source has been requested.
1147 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1148 command, to allow pattern filling of memory areas.
1149 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1150 library load/unload events.
1151 ** The response to breakpoint commands and breakpoint async records
1152 includes an "installed" field containing a boolean state about each
1153 non-pending tracepoint location is whether installed on target or not.
1154 ** Output of the "-trace-status" command includes a "trace-file" field
1155 containing the name of the trace file being examined. This field is
1156 optional, and only present when examining a trace file.
1157 ** The "fullname" field is now always present along with the "file" field,
1158 even if the file cannot be found by GDB.
1160 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1161 You must have the LZMA library available when configuring GDB for this
1162 feature to be enabled. For more information, see:
1163 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1165 * New remote packets
1168 Set the size of trace buffer. The remote stub reports support for this
1169 packet to gdb's qSupported query.
1172 Enable Branch Trace Store (BTS)-based branch tracing for the current
1173 thread. The remote stub reports support for this packet to gdb's
1177 Disable branch tracing for the current thread. The remote stub reports
1178 support for this packet to gdb's qSupported query.
1181 Read the traced branches for the current thread. The remote stub
1182 reports support for this packet to gdb's qSupported query.
1184 *** Changes in GDB 7.5
1186 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1187 for more x32 ABI info.
1189 * GDB now supports access to MIPS DSP registers on Linux targets.
1191 * GDB now supports debugging microMIPS binaries.
1193 * The "info os" command on GNU/Linux can now display information on
1194 several new classes of objects managed by the operating system:
1195 "info os procgroups" lists process groups
1196 "info os files" lists file descriptors
1197 "info os sockets" lists internet-domain sockets
1198 "info os shm" lists shared-memory regions
1199 "info os semaphores" lists semaphores
1200 "info os msg" lists message queues
1201 "info os modules" lists loaded kernel modules
1203 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1204 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1205 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1206 options and inspect the probe arguments using the new $_probe_arg family
1207 of convenience variables. You can obtain more information about SystemTap
1208 in <http://sourceware.org/systemtap/>.
1210 * GDB now supports reversible debugging on ARM, it allows you to
1211 debug basic ARM and THUMB instructions, and provides
1212 record/replay support.
1214 * The option "symbol-reloading" has been deleted as it is no longer used.
1218 ** GDB commands implemented in Python can now be put in command class
1221 ** The "maint set python print-stack on|off" is now deleted.
1223 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1224 apply "flag enum"-style pretty-printing to any enum.
1226 ** gdb.lookup_symbol can now work when there is no current frame.
1228 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1229 the source at which the symbol was defined.
1231 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1232 method 'value'. The former indicates whether the symbol needs a
1233 frame in order to compute its value, and the latter computes the
1236 ** A new method 'referenced_value' on gdb.Value objects which can
1237 dereference pointer as well as C++ reference values.
1239 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1240 which return the global and static blocks (as gdb.Block objects),
1241 of the underlying symbol table, respectively.
1243 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1244 object associated with a PC value.
1246 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1247 of the address range occupied by code for the current source line.
1249 * Go language support.
1250 GDB now supports debugging programs written in the Go programming
1253 * GDBserver now supports stdio connections.
1254 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1256 * The binary "gdbtui" can no longer be built or installed.
1257 Use "gdb -tui" instead.
1259 * GDB will now print "flag" enums specially. A flag enum is one where
1260 all the enumerator values have no bits in common when pairwise
1261 "and"ed. When printing a value whose type is a flag enum, GDB will
1262 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1263 (gdb) print (enum E) 3
1266 * The filename part of a linespec will now match trailing components
1267 of a source file name. For example, "break gcc/expr.c:1000" will
1268 now set a breakpoint in build/gcc/expr.c, but not
1269 build/libcpp/expr.c.
1271 * The "info proc" and "generate-core-file" commands will now also
1272 work on remote targets connected to GDBserver on Linux.
1274 * The command "info catch" has been removed. It has been disabled
1275 since December 2007.
1277 * The "catch exception" and "catch assert" commands now accept
1278 a condition at the end of the command, much like the "break"
1279 command does. For instance:
1281 (gdb) catch exception Constraint_Error if Barrier = True
1283 Previously, it was possible to add a condition to such catchpoints,
1284 but it had to be done as a second step, after the catchpoint had been
1285 created, using the "condition" command.
1287 * The "info static-tracepoint-marker" command will now also work on
1288 native Linux targets with in-process agent.
1290 * GDB can now set breakpoints on inlined functions.
1292 * The .gdb_index section has been updated to include symbols for
1293 inlined functions. GDB will ignore older .gdb_index sections by
1294 default, which could cause symbol files to be loaded more slowly
1295 until their .gdb_index sections can be recreated. The new command
1296 "set use-deprecated-index-sections on" will cause GDB to use any older
1297 .gdb_index sections it finds. This will restore performance, but the
1298 ability to set breakpoints on inlined functions will be lost in symbol
1299 files with older .gdb_index sections.
1301 The .gdb_index section has also been updated to record more information
1302 about each symbol. This speeds up the "info variables", "info functions"
1303 and "info types" commands when used with programs having the .gdb_index
1304 section, as well as speeding up debugging with shared libraries using
1305 the .gdb_index section.
1307 * Ada support for GDB/MI Variable Objects has been added.
1309 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1314 ** New command -info-os is the MI equivalent of "info os".
1316 ** Output logs ("set logging" and related) now include MI output.
1320 ** "set use-deprecated-index-sections on|off"
1321 "show use-deprecated-index-sections on|off"
1322 Controls the use of deprecated .gdb_index sections.
1324 ** "catch load" and "catch unload" can be used to stop when a shared
1325 library is loaded or unloaded, respectively.
1327 ** "enable count" can be used to auto-disable a breakpoint after
1330 ** "info vtbl" can be used to show the virtual method tables for
1331 C++ and Java objects.
1333 ** "explore" and its sub commands "explore value" and "explore type"
1334 can be used to recursively explore values and types of
1335 expressions. These commands are available only if GDB is
1336 configured with '--with-python'.
1338 ** "info auto-load" shows status of all kinds of auto-loaded files,
1339 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1340 sequences of commands files, "info auto-load python-scripts"
1341 shows status of auto-loading Python script files,
1342 "info auto-load local-gdbinit" shows status of loading init file
1343 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1344 status of inferior specific thread debugging shared library loading.
1346 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1347 and "show auto-load-scripts" commands have been deprecated, use their
1348 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1349 and "show auto-load python-scripts" counterparts instead.
1351 ** "dprintf location,format,args..." creates a dynamic printf, which
1352 is basically a breakpoint that does a printf and immediately
1353 resumes your program's execution, so it is like a printf that you
1354 can insert dynamically at runtime instead of at compiletime.
1356 ** "set print symbol"
1358 Controls whether GDB attempts to display the symbol, if any,
1359 corresponding to addresses it prints. This defaults to "on", but
1360 you can set it to "off" to restore GDB's previous behavior.
1362 * Deprecated commands
1364 ** For the Renesas Super-H architecture, the "regs" command has been
1365 deprecated, and "info all-registers" should be used instead.
1369 Renesas RL78 rl78-*-elf
1370 HP OpenVMS ia64 ia64-hp-openvms*
1372 * GDBserver supports evaluation of breakpoint conditions. When
1373 support is advertised by GDBserver, GDB may be told to send the
1374 breakpoint conditions in bytecode form to GDBserver. GDBserver
1375 will only report the breakpoint trigger to GDB when its condition
1380 set mips compression
1381 show mips compression
1382 Select the compressed ISA encoding used in functions that have no symbol
1383 information available. The encoding can be set to either of:
1386 and is updated automatically from ELF file flags if available.
1388 set breakpoint condition-evaluation
1389 show breakpoint condition-evaluation
1390 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1391 GDBserver ("target"). Default option "auto" chooses the most efficient
1393 This option can improve debugger efficiency depending on the speed of the
1397 Disable auto-loading globally.
1400 Show auto-loading setting of all kinds of auto-loaded files.
1402 set auto-load gdb-scripts on|off
1403 show auto-load gdb-scripts
1404 Control auto-loading of GDB canned sequences of commands files.
1406 set auto-load python-scripts on|off
1407 show auto-load python-scripts
1408 Control auto-loading of Python script files.
1410 set auto-load local-gdbinit on|off
1411 show auto-load local-gdbinit
1412 Control loading of init file (.gdbinit) from current directory.
1414 set auto-load libthread-db on|off
1415 show auto-load libthread-db
1416 Control auto-loading of inferior specific thread debugging shared library.
1418 set auto-load scripts-directory <dir1>[:<dir2>...]
1419 show auto-load scripts-directory
1420 Set a list of directories from which to load auto-loaded scripts.
1421 Automatically loaded Python scripts and GDB scripts are located in one
1422 of the directories listed by this option.
1423 The delimiter (':' above) may differ according to the host platform.
1425 set auto-load safe-path <dir1>[:<dir2>...]
1426 show auto-load safe-path
1427 Set a list of directories from which it is safe to auto-load files.
1428 The delimiter (':' above) may differ according to the host platform.
1430 set debug auto-load on|off
1431 show debug auto-load
1432 Control display of debugging info for auto-loading the files above.
1434 set dprintf-style gdb|call|agent
1436 Control the way in which a dynamic printf is performed; "gdb"
1437 requests a GDB printf command, while "call" causes dprintf to call a
1438 function in the inferior. "agent" requests that the target agent
1439 (such as GDBserver) do the printing.
1441 set dprintf-function <expr>
1442 show dprintf-function
1443 set dprintf-channel <expr>
1444 show dprintf-channel
1445 Set the function and optional first argument to the call when using
1446 the "call" style of dynamic printf.
1448 set disconnected-dprintf on|off
1449 show disconnected-dprintf
1450 Control whether agent-style dynamic printfs continue to be in effect
1451 after GDB disconnects.
1453 * New configure options
1455 --with-auto-load-dir
1456 Configure default value for the 'set auto-load scripts-directory'
1457 setting above. It defaults to '$debugdir:$datadir/auto-load',
1458 $debugdir representing global debugging info directories (available
1459 via 'show debug-file-directory') and $datadir representing GDB's data
1460 directory (available via 'show data-directory').
1462 --with-auto-load-safe-path
1463 Configure default value for the 'set auto-load safe-path' setting
1464 above. It defaults to the --with-auto-load-dir setting.
1466 --without-auto-load-safe-path
1467 Set 'set auto-load safe-path' to '/', effectively disabling this
1470 * New remote packets
1472 z0/z1 conditional breakpoints extension
1474 The z0/z1 breakpoint insertion packets have been extended to carry
1475 a list of conditional expressions over to the remote stub depending on the
1476 condition evaluation mode. The use of this extension can be controlled
1477 via the "set remote conditional-breakpoints-packet" command.
1481 Specify the signals which the remote stub may pass to the debugged
1482 program without GDB involvement.
1484 * New command line options
1486 --init-command=FILE, -ix Like --command, -x but execute it
1487 before loading inferior.
1488 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1489 execute it before loading inferior.
1491 *** Changes in GDB 7.4
1493 * GDB now handles ambiguous linespecs more consistently; the existing
1494 FILE:LINE support has been expanded to other types of linespecs. A
1495 breakpoint will now be set on all matching locations in all
1496 inferiors, and locations will be added or removed according to
1499 * GDB now allows you to skip uninteresting functions and files when
1500 stepping with the "skip function" and "skip file" commands.
1502 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1503 and "show remote hardware-watchpoint-length-limit". These allows to
1504 set or show the maximum length limit (in bytes) of a remote
1505 target hardware watchpoint.
1507 This allows e.g. to use "unlimited" hardware watchpoints with the
1508 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1509 watchpoints are slower than real hardware watchpoints but are
1510 significantly faster than gdb software watchpoints.
1514 ** The register_pretty_printer function in module gdb.printing now takes
1515 an optional `replace' argument. If True, the new printer replaces any
1518 ** The "maint set python print-stack on|off" command has been
1519 deprecated and will be deleted in GDB 7.5.
1520 A new command: "set python print-stack none|full|message" has
1521 replaced it. Additionally, the default for "print-stack" is
1522 now "message", which just prints the error message without
1525 ** A prompt substitution hook (prompt_hook) is now available to the
1528 ** A new Python module, gdb.prompt has been added to the GDB Python
1529 modules library. This module provides functionality for
1530 escape sequences in prompts (used by set/show
1531 extended-prompt). These escape sequences are replaced by their
1532 corresponding value.
1534 ** Python commands and convenience-functions located in
1535 'data-directory'/python/gdb/command and
1536 'data-directory'/python/gdb/function are now automatically loaded
1539 ** Blocks now provide four new attributes. global_block and
1540 static_block will return the global and static blocks
1541 respectively. is_static and is_global are boolean attributes
1542 that indicate if the block is one of those two types.
1544 ** Symbols now provide the "type" attribute, the type of the symbol.
1546 ** The "gdb.breakpoint" function has been deprecated in favor of
1549 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1550 of a function. This class is based on the "finish" command
1551 available in the CLI.
1553 ** Type objects for struct and union types now allow access to
1554 the fields using standard Python dictionary (mapping) methods.
1555 For example, "some_type['myfield']" now works, as does
1556 "some_type.items()".
1558 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1561 ** A new function, "deep_items" has been added to the gdb.types
1562 module in the GDB Python modules library. This function returns
1563 an iterator over the fields of a struct or union type. Unlike
1564 the standard Python "iteritems" method, it will recursively traverse
1565 any anonymous fields.
1569 ** "*stopped" events can report several new "reason"s, such as
1572 ** Breakpoint changes are now notified using new async records, like
1573 "=breakpoint-modified".
1575 ** New command -ada-task-info.
1577 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1578 $sdir specifies the default system locations of shared libraries.
1579 $pdir specifies the directory where the libpthread used by the application
1582 GDB no longer looks in $sdir and $pdir after it has searched the directories
1583 mentioned in libthread-db-search-path. If you want to search those
1584 directories, they must be specified in libthread-db-search-path.
1585 The default value of libthread-db-search-path on GNU/Linux and Solaris
1586 systems is now "$sdir:$pdir".
1588 $pdir is not supported by gdbserver, it is currently ignored.
1589 $sdir is supported by gdbserver.
1591 * New configure option --with-iconv-bin.
1592 When using the internationalization support like the one in the GNU C
1593 library, GDB will invoke the "iconv" program to get a list of supported
1594 character sets. If this program lives in a non-standard location, one can
1595 use this option to specify where to find it.
1597 * When natively debugging programs on PowerPC BookE processors running
1598 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1599 watchpoints, which specify a mask in addition to an address to watch.
1600 The mask specifies that some bits of an address (the bits which are
1601 reset in the mask) should be ignored when matching the address accessed
1602 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1603 section in the user manual for more details.
1605 * The new option --once causes GDBserver to stop listening for connections once
1606 the first connection is made. The listening port used by GDBserver will
1607 become available after that.
1609 * New commands "info macros" and "alias" have been added.
1611 * New function parameters suffix @entry specifies value of function parameter
1612 at the time the function got called. Entry values are available only since
1618 "!" is now an alias of the "shell" command.
1619 Note that no space is needed between "!" and SHELL COMMAND.
1623 watch EXPRESSION mask MASK_VALUE
1624 The watch command now supports the mask argument which allows creation
1625 of masked watchpoints, if the current architecture supports this feature.
1627 info auto-load-scripts [REGEXP]
1628 This command was formerly named "maintenance print section-scripts".
1629 It is now generally useful and is no longer a maintenance-only command.
1631 info macro [-all] [--] MACRO
1632 The info macro command has new options `-all' and `--'. The first for
1633 printing all definitions of a macro. The second for explicitly specifying
1634 the end of arguments and the beginning of the macro name in case the macro
1635 name starts with a hyphen.
1637 collect[/s] EXPRESSIONS
1638 The tracepoint collect command now takes an optional modifier "/s"
1639 that directs it to dereference pointer-to-character types and
1640 collect the bytes of memory up to a zero byte. The behavior is
1641 similar to what you see when you use the regular print command on a
1642 string. An optional integer following the "/s" sets a bound on the
1643 number of bytes that will be collected.
1646 The trace start command now interprets any supplied arguments as a
1647 note to be recorded with the trace run, with an effect similar to
1648 setting the variable trace-notes.
1651 The trace stop command now interprets any arguments as a note to be
1652 mentioned along with the tstatus report that the trace was stopped
1653 with a command. The effect is similar to setting the variable
1656 * Tracepoints can now be enabled and disabled at any time after a trace
1657 experiment has been started using the standard "enable" and "disable"
1658 commands. It is now possible to start a trace experiment with no enabled
1659 tracepoints; GDB will display a warning, but will allow the experiment to
1660 begin, assuming that tracepoints will be enabled as needed while the trace
1663 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1664 locations with 4-byte instructions, when they were previously
1665 limited to locations with instructions of 5 bytes or longer.
1669 set debug dwarf2-read
1670 show debug dwarf2-read
1671 Turns on or off display of debugging messages related to reading
1672 DWARF debug info. The default is off.
1674 set debug symtab-create
1675 show debug symtab-create
1676 Turns on or off display of debugging messages related to symbol table
1677 creation. The default is off.
1680 show extended-prompt
1681 Set the GDB prompt, and allow escape sequences to be inserted to
1682 display miscellaneous information (see 'help set extended-prompt'
1683 for the list of sequences). This prompt (and any information
1684 accessed through the escape sequences) is updated every time the
1685 prompt is displayed.
1687 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1688 show print entry-values
1689 Set printing of frame argument values at function entry. In some cases
1690 GDB can determine the value of function argument which was passed by the
1691 function caller, even if the value was modified inside the called function.
1693 set debug entry-values
1694 show debug entry-values
1695 Control display of debugging info for determining frame argument values at
1696 function entry and virtual tail call frames.
1698 set basenames-may-differ
1699 show basenames-may-differ
1700 Set whether a source file may have multiple base names.
1701 (A "base name" is the name of a file with the directory part removed.
1702 Example: The base name of "/home/user/hello.c" is "hello.c".)
1703 If set, GDB will canonicalize file names (e.g., expand symlinks)
1704 before comparing them. Canonicalization is an expensive operation,
1705 but it allows the same file be known by more than one base name.
1706 If not set (the default), all source files are assumed to have just
1707 one base name, and gdb will do file name comparisons more efficiently.
1713 Set a user name and notes for the current and any future trace runs.
1714 This is useful for long-running and/or disconnected traces, to
1715 inform others (or yourself) as to who is running the trace, supply
1716 contact information, or otherwise explain what is going on.
1718 set trace-stop-notes
1719 show trace-stop-notes
1720 Set a note attached to the trace run, that is displayed when the
1721 trace has been stopped by a tstop command. This is useful for
1722 instance as an explanation, if you are stopping a trace run that was
1723 started by someone else.
1725 * New remote packets
1729 Dynamically enable a tracepoint in a started trace experiment.
1733 Dynamically disable a tracepoint in a started trace experiment.
1737 Set the user and notes of the trace run.
1741 Query the current status of a tracepoint.
1745 Query the minimum length of instruction at which a fast tracepoint may
1748 * Dcache size (number of lines) and line-size are now runtime-configurable
1749 via "set dcache line" and "set dcache line-size" commands.
1753 Texas Instruments TMS320C6x tic6x-*-*
1757 Renesas RL78 rl78-*-elf
1759 *** Changes in GDB 7.3.1
1761 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1763 *** Changes in GDB 7.3
1765 * GDB has a new command: "thread find [REGEXP]".
1766 It finds the thread id whose name, target id, or thread extra info
1767 matches the given regular expression.
1769 * The "catch syscall" command now works on mips*-linux* targets.
1771 * The -data-disassemble MI command now supports modes 2 and 3 for
1772 dumping the instruction opcodes.
1774 * New command line options
1776 -data-directory DIR Specify DIR as the "data-directory".
1777 This is mostly for testing purposes.
1779 * The "maint set python auto-load on|off" command has been renamed to
1780 "set auto-load-scripts on|off".
1782 * GDB has a new command: "set directories".
1783 It is like the "dir" command except that it replaces the
1784 source path list instead of augmenting it.
1786 * GDB now understands thread names.
1788 On GNU/Linux, "info threads" will display the thread name as set by
1789 prctl or pthread_setname_np.
1791 There is also a new command, "thread name", which can be used to
1792 assign a name internally for GDB to display.
1795 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1796 has been integrated into GDB.
1800 ** The function gdb.Write now accepts an optional keyword 'stream'.
1801 This keyword, when provided, will direct the output to either
1802 stdout, stderr, or GDB's logging output.
1804 ** Parameters can now be be sub-classed in Python, and in particular
1805 you may implement the get_set_doc and get_show_doc functions.
1806 This improves how Parameter set/show documentation is processed
1807 and allows for more dynamic content.
1809 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1810 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1811 have an is_valid method.
1813 ** Breakpoints can now be sub-classed in Python, and in particular
1814 you may implement a 'stop' function that is executed each time
1815 the inferior reaches that breakpoint.
1817 ** New function gdb.lookup_global_symbol looks up a global symbol.
1819 ** GDB values in Python are now callable if the value represents a
1820 function. For example, if 'some_value' represents a function that
1821 takes two integer parameters and returns a value, you can call
1822 that function like so:
1824 result = some_value (10,20)
1826 ** Module gdb.types has been added.
1827 It contains a collection of utilities for working with gdb.Types objects:
1828 get_basic_type, has_field, make_enum_dict.
1830 ** Module gdb.printing has been added.
1831 It contains utilities for writing and registering pretty-printers.
1832 New classes: PrettyPrinter, SubPrettyPrinter,
1833 RegexpCollectionPrettyPrinter.
1834 New function: register_pretty_printer.
1836 ** New commands "info pretty-printers", "enable pretty-printer" and
1837 "disable pretty-printer" have been added.
1839 ** gdb.parameter("directories") is now available.
1841 ** New function gdb.newest_frame returns the newest frame in the
1844 ** The gdb.InferiorThread class has a new "name" attribute. This
1845 holds the thread's name.
1847 ** Python Support for Inferior events.
1848 Python scripts can add observers to be notified of events
1849 occurring in the process being debugged.
1850 The following events are currently supported:
1851 - gdb.events.cont Continue event.
1852 - gdb.events.exited Inferior exited event.
1853 - gdb.events.stop Signal received, and Breakpoint hit events.
1857 ** GDB now puts template parameters in scope when debugging in an
1858 instantiation. For example, if you have:
1860 template<int X> int func (void) { return X; }
1862 then if you step into func<5>, "print X" will show "5". This
1863 feature requires proper debuginfo support from the compiler; it
1864 was added to GCC 4.5.
1866 ** The motion commands "next", "finish", "until", and "advance" now
1867 work better when exceptions are thrown. In particular, GDB will
1868 no longer lose control of the inferior; instead, the GDB will
1869 stop the inferior at the point at which the exception is caught.
1870 This functionality requires a change in the exception handling
1871 code that was introduced in GCC 4.5.
1873 * GDB now follows GCC's rules on accessing volatile objects when
1874 reading or writing target state during expression evaluation.
1875 One notable difference to prior behavior is that "print x = 0"
1876 no longer generates a read of x; the value of the assignment is
1877 now always taken directly from the value being assigned.
1879 * GDB now has some support for using labels in the program's source in
1880 linespecs. For instance, you can use "advance label" to continue
1881 execution to a label.
1883 * GDB now has support for reading and writing a new .gdb_index
1884 section. This section holds a fast index of DWARF debugging
1885 information and can be used to greatly speed up GDB startup and
1886 operation. See the documentation for `save gdb-index' for details.
1888 * The "watch" command now accepts an optional "-location" argument.
1889 When used, this causes GDB to watch the memory referred to by the
1890 expression. Such a watchpoint is never deleted due to it going out
1893 * GDB now supports thread debugging of core dumps on GNU/Linux.
1895 GDB now activates thread debugging using the libthread_db library
1896 when debugging GNU/Linux core dumps, similarly to when debugging
1897 live processes. As a result, when debugging a core dump file, GDB
1898 is now able to display pthread_t ids of threads. For example, "info
1899 threads" shows the same output as when debugging the process when it
1900 was live. In earlier releases, you'd see something like this:
1903 * 1 LWP 6780 main () at main.c:10
1905 While now you see this:
1908 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1910 It is also now possible to inspect TLS variables when debugging core
1913 When debugging a core dump generated on a machine other than the one
1914 used to run GDB, you may need to point GDB at the correct
1915 libthread_db library with the "set libthread-db-search-path"
1916 command. See the user manual for more details on this command.
1918 * When natively debugging programs on PowerPC BookE processors running
1919 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1920 which stop execution of the inferior whenever it executes an instruction
1921 at any address within the specified range. See the "PowerPC Embedded"
1922 section in the user manual for more details.
1924 * New features in the GDB remote stub, GDBserver
1926 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1927 and i686 LynxOS (version 5.x).
1929 ** GDBserver is now supported on Blackfin Linux.
1931 * New native configurations
1933 ia64 HP-UX ia64-*-hpux*
1937 Analog Devices, Inc. Blackfin Processor bfin-*
1939 * Ada task switching is now supported on sparc-elf targets when
1940 debugging a program using the Ravenscar Profile. For more information,
1941 see the "Tasking Support when using the Ravenscar Profile" section
1942 in the GDB user manual.
1944 * Guile support was removed.
1946 * New features in the GNU simulator
1948 ** The --map-info flag lists all known core mappings.
1950 ** CFI flashes may be simulated via the "cfi" device.
1952 *** Changes in GDB 7.2
1954 * Shared library support for remote targets by default
1956 When GDB is configured for a generic, non-OS specific target, like
1957 for example, --target=arm-eabi or one of the many *-*-elf targets,
1958 GDB now queries remote stubs for loaded shared libraries using the
1959 `qXfer:libraries:read' packet. Previously, shared library support
1960 was always disabled for such configurations.
1964 ** Argument Dependent Lookup (ADL)
1966 In C++ ADL lookup directs function search to the namespaces of its
1967 arguments even if the namespace has not been imported.
1977 Here the compiler will search for `foo' in the namespace of 'b'
1978 and find A::foo. GDB now supports this. This construct is commonly
1979 used in the Standard Template Library for operators.
1981 ** Improved User Defined Operator Support
1983 In addition to member operators, GDB now supports lookup of operators
1984 defined in a namespace and imported with a `using' directive, operators
1985 defined in the global scope, operators imported implicitly from an
1986 anonymous namespace, and the ADL operators mentioned in the previous
1988 GDB now also supports proper overload resolution for all the previously
1989 mentioned flavors of operators.
1991 ** static const class members
1993 Printing of static const class members that are initialized in the
1994 class definition has been fixed.
1996 * Windows Thread Information Block access.
1998 On Windows targets, GDB now supports displaying the Windows Thread
1999 Information Block (TIB) structure. This structure is visible either
2000 by using the new command `info w32 thread-information-block' or, by
2001 dereferencing the new convenience variable named `$_tlb', a
2002 thread-specific pointer to the TIB. This feature is also supported
2003 when remote debugging using GDBserver.
2005 * Static tracepoints
2007 Static tracepoints are calls in the user program into a tracing
2008 library. One such library is a port of the LTTng kernel tracer to
2009 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2010 When debugging with GDBserver, GDB now supports combining the GDB
2011 tracepoint machinery with such libraries. For example: the user can
2012 use GDB to probe a static tracepoint marker (a call from the user
2013 program into the tracing library) with the new "strace" command (see
2014 "New commands" below). This creates a "static tracepoint" in the
2015 breakpoint list, that can be manipulated with the same feature set
2016 as fast and regular tracepoints. E.g., collect registers, local and
2017 global variables, collect trace state variables, and define
2018 tracepoint conditions. In addition, the user can collect extra
2019 static tracepoint marker specific data, by collecting the new
2020 $_sdata internal variable. When analyzing the trace buffer, you can
2021 inspect $_sdata like any other variable available to GDB. For more
2022 information, see the "Tracepoints" chapter in GDB user manual. New
2023 remote packets have been defined to support static tracepoints, see
2024 the "New remote packets" section below.
2026 * Better reconstruction of tracepoints after disconnected tracing
2028 GDB will attempt to download the original source form of tracepoint
2029 definitions when starting a trace run, and then will upload these
2030 upon reconnection to the target, resulting in a more accurate
2031 reconstruction of the tracepoints that are in use on the target.
2035 You can now exercise direct control over the ways that GDB can
2036 affect your program. For instance, you can disallow the setting of
2037 breakpoints, so that the program can run continuously (assuming
2038 non-stop mode). In addition, the "observer" variable is available
2039 to switch all of the different controls; in observer mode, GDB
2040 cannot affect the target's behavior at all, which is useful for
2041 tasks like diagnosing live systems in the field.
2043 * The new convenience variable $_thread holds the number of the
2046 * New remote packets
2050 Return the address of the Windows Thread Information Block of a given thread.
2054 In response to several of the tracepoint packets, the target may now
2055 also respond with a number of intermediate `qRelocInsn' request
2056 packets before the final result packet, to have GDB handle
2057 relocating an instruction to execute at a different address. This
2058 is particularly useful for stubs that support fast tracepoints. GDB
2059 reports support for this feature in the qSupported packet.
2063 List static tracepoint markers in the target program.
2067 List static tracepoint markers at a given address in the target
2070 qXfer:statictrace:read
2072 Read the static trace data collected (by a `collect $_sdata'
2073 tracepoint action). The remote stub reports support for this packet
2074 to gdb's qSupported query.
2078 Send the current settings of GDB's permission flags.
2082 Send part of the source (textual) form of a tracepoint definition,
2083 which includes location, conditional, and action list.
2085 * The source command now accepts a -s option to force searching for the
2086 script in the source search path even if the script name specifies
2089 * New features in the GDB remote stub, GDBserver
2091 - GDBserver now support tracepoints (including fast tracepoints, and
2092 static tracepoints). The feature is currently supported by the
2093 i386-linux and amd64-linux builds. See the "Tracepoints support
2094 in gdbserver" section in the manual for more information.
2096 GDBserver JIT compiles the tracepoint's conditional agent
2097 expression bytecode into native code whenever possible for low
2098 overhead dynamic tracepoints conditionals. For such tracepoints,
2099 an expression that examines program state is evaluated when the
2100 tracepoint is reached, in order to determine whether to capture
2101 trace data. If the condition is simple and false, processing the
2102 tracepoint finishes very quickly and no data is gathered.
2104 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2105 for static tracepoints support.
2107 - GDBserver now supports x86_64 Windows 64-bit debugging.
2109 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2110 it understands register description.
2112 * The --batch flag now disables pagination and queries.
2114 * X86 general purpose registers
2116 GDB now supports reading/writing byte, word and double-word x86
2117 general purpose registers directly. This means you can use, say,
2118 $ah or $ax to refer, respectively, to the byte register AH and
2119 16-bit word register AX that are actually portions of the 32-bit
2120 register EAX or 64-bit register RAX.
2122 * The `commands' command now accepts a range of breakpoints to modify.
2123 A plain `commands' following a command that creates multiple
2124 breakpoints affects all the breakpoints set by that command. This
2125 applies to breakpoints set by `rbreak', and also applies when a
2126 single `break' command creates multiple breakpoints (e.g.,
2127 breakpoints on overloaded c++ functions).
2129 * The `rbreak' command now accepts a filename specification as part of
2130 its argument, limiting the functions selected by the regex to those
2131 in the specified file.
2133 * Support for remote debugging Windows and SymbianOS shared libraries
2134 from Unix hosts has been improved. Non Windows GDB builds now can
2135 understand target reported file names that follow MS-DOS based file
2136 system semantics, such as file names that include drive letters and
2137 use the backslash character as directory separator. This makes it
2138 possible to transparently use the "set sysroot" and "set
2139 solib-search-path" on Unix hosts to point as host copies of the
2140 target's shared libraries. See the new command "set
2141 target-file-system-kind" described below, and the "Commands to
2142 specify files" section in the user manual for more information.
2146 eval template, expressions...
2147 Convert the values of one or more expressions under the control
2148 of the string template to a command line, and call it.
2150 set target-file-system-kind unix|dos-based|auto
2151 show target-file-system-kind
2152 Set or show the assumed file system kind for target reported file
2155 save breakpoints <filename>
2156 Save all current breakpoint definitions to a file suitable for use
2157 in a later debugging session. To read the saved breakpoint
2158 definitions, use the `source' command.
2160 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2163 info static-tracepoint-markers
2164 Display information about static tracepoint markers in the target.
2166 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2167 Define a static tracepoint by probing a marker at the given
2168 function, line, address, or marker ID.
2172 Enable and disable observer mode.
2174 set may-write-registers on|off
2175 set may-write-memory on|off
2176 set may-insert-breakpoints on|off
2177 set may-insert-tracepoints on|off
2178 set may-insert-fast-tracepoints on|off
2179 set may-interrupt on|off
2180 Set individual permissions for GDB effects on the target. Note that
2181 some of these settings can have undesirable or surprising
2182 consequences, particularly when changed in the middle of a session.
2183 For instance, disabling the writing of memory can prevent
2184 breakpoints from being inserted, cause single-stepping to fail, or
2185 even crash your program, if you disable after breakpoints have been
2186 inserted. However, GDB should not crash.
2188 set record memory-query on|off
2189 show record memory-query
2190 Control whether to stop the inferior if memory changes caused
2191 by an instruction cannot be recorded.
2196 The disassemble command now supports "start,+length" form of two arguments.
2200 ** GDB now provides a new directory location, called the python directory,
2201 where Python scripts written for GDB can be installed. The location
2202 of that directory is <data-directory>/python, where <data-directory>
2203 is the GDB data directory. For more details, see section `Scripting
2204 GDB using Python' in the manual.
2206 ** The GDB Python API now has access to breakpoints, symbols, symbol
2207 tables, program spaces, inferiors, threads and frame's code blocks.
2208 Additionally, GDB Parameters can now be created from the API, and
2209 manipulated via set/show in the CLI.
2211 ** New functions gdb.target_charset, gdb.target_wide_charset,
2212 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2214 ** New exception gdb.GdbError.
2216 ** Pretty-printers are now also looked up in the current program space.
2218 ** Pretty-printers can now be individually enabled and disabled.
2220 ** GDB now looks for names of Python scripts to auto-load in a
2221 special section named `.debug_gdb_scripts', in addition to looking
2222 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2224 * Tracepoint actions were unified with breakpoint commands. In particular,
2225 there are no longer differences in "info break" output for breakpoints and
2226 tracepoints and the "commands" command can be used for both tracepoints and
2227 regular breakpoints.
2231 ARM Symbian arm*-*-symbianelf*
2233 * D language support.
2234 GDB now supports debugging programs written in the D programming
2237 * GDB now supports the extended ptrace interface for PowerPC which is
2238 available since Linux kernel version 2.6.34. This automatically enables
2239 any hardware breakpoints and additional hardware watchpoints available in
2240 the processor. The old ptrace interface exposes just one hardware
2241 watchpoint and no hardware breakpoints.
2243 * GDB is now able to use the Data Value Compare (DVC) register available on
2244 embedded PowerPC processors to implement in hardware simple watchpoint
2245 conditions of the form:
2247 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2249 This works in native GDB running on Linux kernels with the extended ptrace
2250 interface mentioned above.
2252 *** Changes in GDB 7.1
2256 ** Namespace Support
2258 GDB now supports importing of namespaces in C++. This enables the
2259 user to inspect variables from imported namespaces. Support for
2260 namepace aliasing has also been added. So, if a namespace is
2261 aliased in the current scope (e.g. namepace C=A; ) the user can
2262 print variables using the alias (e.g. (gdb) print C::x).
2266 All known bugs relating to the printing of virtual base class were
2267 fixed. It is now possible to call overloaded static methods using a
2272 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2273 and reinterpret_cast<> are now handled by the C++ expression parser.
2277 Xilinx MicroBlaze microblaze-*-*
2282 Xilinx MicroBlaze microblaze
2285 * Multi-program debugging.
2287 GDB now has support for multi-program (a.k.a. multi-executable or
2288 multi-exec) debugging. This allows for debugging multiple inferiors
2289 simultaneously each running a different program under the same GDB
2290 session. See "Debugging Multiple Inferiors and Programs" in the
2291 manual for more information. This implied some user visible changes
2292 in the multi-inferior support. For example, "info inferiors" now
2293 lists inferiors that are not running yet or that have exited
2294 already. See also "New commands" and "New options" below.
2296 * New tracing features
2298 GDB's tracepoint facility now includes several new features:
2300 ** Trace state variables
2302 GDB tracepoints now include support for trace state variables, which
2303 are variables managed by the target agent during a tracing
2304 experiment. They are useful for tracepoints that trigger each
2305 other, so for instance one tracepoint can count hits in a variable,
2306 and then a second tracepoint has a condition that is true when the
2307 count reaches a particular value. Trace state variables share the
2308 $-syntax of GDB convenience variables, and can appear in both
2309 tracepoint actions and condition expressions. Use the "tvariable"
2310 command to create, and "info tvariables" to view; see "Trace State
2311 Variables" in the manual for more detail.
2315 GDB now includes an option for defining fast tracepoints, which
2316 targets may implement more efficiently, such as by installing a jump
2317 into the target agent rather than a trap instruction. The resulting
2318 speedup can be by two orders of magnitude or more, although the
2319 tradeoff is that some program locations on some target architectures
2320 might not allow fast tracepoint installation, for instance if the
2321 instruction to be replaced is shorter than the jump. To request a
2322 fast tracepoint, use the "ftrace" command, with syntax identical to
2323 the regular trace command.
2325 ** Disconnected tracing
2327 It is now possible to detach GDB from the target while it is running
2328 a trace experiment, then reconnect later to see how the experiment
2329 is going. In addition, a new variable disconnected-tracing lets you
2330 tell the target agent whether to continue running a trace if the
2331 connection is lost unexpectedly.
2335 GDB now has the ability to save the trace buffer into a file, and
2336 then use that file as a target, similarly to you can do with
2337 corefiles. You can select trace frames, print data that was
2338 collected in them, and use tstatus to display the state of the
2339 tracing run at the moment that it was saved. To create a trace
2340 file, use "tsave <filename>", and to use it, do "target tfile
2343 ** Circular trace buffer
2345 You can ask the target agent to handle the trace buffer as a
2346 circular buffer, discarding the oldest trace frames to make room for
2347 newer ones, by setting circular-trace-buffer to on. This feature may
2348 not be available for all target agents.
2353 The disassemble command, when invoked with two arguments, now requires
2354 the arguments to be comma-separated.
2357 The info variables command now displays variable definitions. Files
2358 which only declare a variable are not shown.
2361 The source command is now capable of sourcing Python scripts.
2362 This feature is dependent on the debugger being build with Python
2365 Related to this enhancement is also the introduction of a new command
2366 "set script-extension" (see below).
2368 * New commands (for set/show, see "New options" below)
2370 record save [<FILENAME>]
2371 Save a file (in core file format) containing the process record
2372 execution log for replay debugging at a later time.
2374 record restore <FILENAME>
2375 Restore the process record execution log that was saved at an
2376 earlier time, for replay debugging.
2378 add-inferior [-copies <N>] [-exec <FILENAME>]
2381 clone-inferior [-copies <N>] [ID]
2382 Make a new inferior ready to execute the same program another
2383 inferior has loaded.
2388 maint info program-spaces
2389 List the program spaces loaded into GDB.
2391 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2392 show remote interrupt-sequence
2393 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2394 as the sequence to the remote target in order to interrupt the execution.
2395 Ctrl-C is a default. Some system prefers BREAK which is high level of
2396 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2397 Magic SysRq g. It is BREAK signal and character 'g'.
2399 set remote interrupt-on-connect [on | off]
2400 show remote interrupt-on-connect
2401 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2402 remote target when gdb connects to it. This is needed when you debug
2405 set remotebreak [on | off]
2407 Deprecated. Use "set/show remote interrupt-sequence" instead.
2409 tvariable $NAME [ = EXP ]
2410 Create or modify a trace state variable.
2413 List trace state variables and their values.
2415 delete tvariable $NAME ...
2416 Delete one or more trace state variables.
2419 Evaluate the given expressions without collecting anything into the
2420 trace buffer. (Valid in tracepoint actions only.)
2422 ftrace FN / FILE:LINE / *ADDR
2423 Define a fast tracepoint at the given function, line, or address.
2425 * New expression syntax
2427 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2428 GDB now parses 0b101010 identically with 42.
2432 set follow-exec-mode new|same
2433 show follow-exec-mode
2434 Control whether GDB reuses the same inferior across an exec call or
2435 creates a new one. This is useful to be able to restart the old
2436 executable after the inferior having done an exec call.
2438 set default-collect EXPR, ...
2439 show default-collect
2440 Define a list of expressions to be collected at each tracepoint.
2441 This is a useful way to ensure essential items are not overlooked,
2442 such as registers or a critical global variable.
2444 set disconnected-tracing
2445 show disconnected-tracing
2446 If set to 1, the target is instructed to continue tracing if it
2447 loses its connection to GDB. If 0, the target is to stop tracing
2450 set circular-trace-buffer
2451 show circular-trace-buffer
2452 If set to on, the target is instructed to use a circular trace buffer
2453 and discard the oldest trace frames instead of stopping the trace due
2454 to a full trace buffer. If set to off, the trace stops when the buffer
2455 fills up. Some targets may not support this.
2457 set script-extension off|soft|strict
2458 show script-extension
2459 If set to "off", the debugger does not perform any script language
2460 recognition, and all sourced files are assumed to be GDB scripts.
2461 If set to "soft" (the default), files are sourced according to
2462 filename extension, falling back to GDB scripts if the first
2464 If set to "strict", files are sourced according to filename extension.
2466 set ada trust-PAD-over-XVS on|off
2467 show ada trust-PAD-over-XVS
2468 If off, activate a workaround against a bug in the debugging information
2469 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2470 the GCC sources for more information about the GNAT encoding and
2471 PAD types in particular). It is always safe to set this option to
2472 off, but this introduces a slight performance penalty. The default
2475 * Python API Improvements
2477 ** GDB provides the new class gdb.LazyString. This is useful in
2478 some pretty-printing cases. The new method gdb.Value.lazy_string
2479 provides a simple way to create objects of this type.
2481 ** The fields returned by gdb.Type.fields now have an
2482 `is_base_class' attribute.
2484 ** The new method gdb.Type.range returns the range of an array type.
2486 ** The new method gdb.parse_and_eval can be used to parse and
2487 evaluate an expression.
2489 * New remote packets
2492 Define a trace state variable.
2495 Get the current value of a trace state variable.
2498 Set desired tracing behavior upon disconnection.
2501 Set the trace buffer to be linear or circular.
2504 Get data about the tracepoints currently in use.
2508 Process record now works correctly with hardware watchpoints.
2510 Multiple bug fixes have been made to the mips-irix port, making it
2511 much more reliable. In particular:
2512 - Debugging threaded applications is now possible again. Previously,
2513 GDB would hang while starting the program, or while waiting for
2514 the program to stop at a breakpoint.
2515 - Attaching to a running process no longer hangs.
2516 - An error occurring while loading a core file has been fixed.
2517 - Changing the value of the PC register now works again. This fixes
2518 problems observed when using the "jump" command, or when calling
2519 a function from GDB, or even when assigning a new value to $pc.
2520 - With the "finish" and "return" commands, the return value for functions
2521 returning a small array is now correctly printed.
2522 - It is now possible to break on shared library code which gets executed
2523 during a shared library init phase (code executed while executing
2524 their .init section). Previously, the breakpoint would have no effect.
2525 - GDB is now able to backtrace through the signal handler for
2526 non-threaded programs.
2528 PIE (Position Independent Executable) programs debugging is now supported.
2529 This includes debugging execution of PIC (Position Independent Code) shared
2530 libraries although for that, it should be possible to run such libraries as an
2533 *** Changes in GDB 7.0
2535 * GDB now has an interface for JIT compilation. Applications that
2536 dynamically generate code can create symbol files in memory and register
2537 them with GDB. For users, the feature should work transparently, and
2538 for JIT developers, the interface is documented in the GDB manual in the
2539 "JIT Compilation Interface" chapter.
2541 * Tracepoints may now be conditional. The syntax is as for
2542 breakpoints; either an "if" clause appended to the "trace" command,
2543 or the "condition" command is available. GDB sends the condition to
2544 the target for evaluation using the same bytecode format as is used
2545 for tracepoint actions.
2547 * The disassemble command now supports: an optional /r modifier, print the
2548 raw instructions in hex as well as in symbolic form, and an optional /m
2549 modifier to print mixed source+assembly.
2551 * Process record and replay
2553 In a architecture environment that supports ``process record and
2554 replay'', ``process record and replay'' target can record a log of
2555 the process execution, and replay it with both forward and reverse
2558 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2559 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2560 set execution-direction {forward|reverse}, for targets that support
2563 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2564 feature is available with a native GDB running on kernel version
2567 * GDB now has support for multi-byte and wide character sets on the
2568 target. Strings whose character type is wchar_t, char16_t, or
2569 char32_t are now correctly printed. GDB supports wide- and unicode-
2570 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2571 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2572 `printf'. This feature requires iconv to work properly; if your
2573 system does not have a working iconv, GDB can use GNU libiconv. See
2574 the installation instructions for more information.
2576 * GDB now supports automatic retrieval of shared library files from
2577 remote targets. To use this feature, specify a system root that begins
2578 with the `remote:' prefix, either via the `set sysroot' command or via
2579 the `--with-sysroot' configure-time option.
2581 * "info sharedlibrary" now takes an optional regex of libraries to show,
2582 and it now reports if a shared library has no debugging information.
2584 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2585 now complete on file names.
2587 * When completing in expressions, gdb will attempt to limit
2588 completions to allowable structure or union fields, where appropriate.
2589 For instance, consider:
2591 # struct example { int f1; double f2; };
2592 # struct example variable;
2595 If the user types TAB at the end of this command line, the available
2596 completions will be "f1" and "f2".
2598 * Inlined functions are now supported. They show up in backtraces, and
2599 the "step", "next", and "finish" commands handle them automatically.
2601 * GDB now supports the token-splicing (##) and stringification (#)
2602 operators when expanding macros. It also supports variable-arity
2605 * GDB now supports inspecting extra signal information, exported by
2606 the new $_siginfo convenience variable. The feature is currently
2607 implemented on linux ARM, i386 and amd64.
2609 * GDB can now display the VFP floating point registers and NEON vector
2610 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2611 can provide these registers (requires Linux 2.6.30 or later). Remote
2612 and simulator targets may also provide them.
2614 * New remote packets
2617 Search memory for a sequence of bytes.
2620 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2621 operation over reliable transport links. Use of this packet is
2622 controlled by the `set remote noack-packet' command.
2625 Kill the process with the specified process ID. Use this in preference
2626 to `k' when multiprocess protocol extensions are supported.
2629 Obtains additional operating system information
2633 Read or write additional signal information.
2635 * Removed remote protocol undocumented extension
2637 An undocumented extension to the remote protocol's `S' stop reply
2638 packet that permited the stub to pass a process id was removed.
2639 Remote servers should use the `T' stop reply packet instead.
2641 * GDB now supports multiple function calling conventions according to the
2642 DWARF-2 DW_AT_calling_convention function attribute.
2644 * The SH target utilizes the aforementioned change to distinguish between gcc
2645 and Renesas calling convention. It also adds the new CLI commands
2646 `set/show sh calling-convention'.
2648 * GDB can now read compressed debug sections, as produced by GNU gold
2649 with the --compress-debug-sections=zlib flag.
2651 * 64-bit core files are now supported on AIX.
2653 * Thread switching is now supported on Tru64.
2655 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2656 which will be allocated using malloc later in program execution.
2658 * The qXfer:libraries:read remote procotol packet now allows passing a
2659 list of section offsets.
2661 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2662 conditions handling signals delivered during attach or thread creation
2663 have also been fixed.
2665 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2666 From the user's standpoint, all unqualified instances of True and False
2667 are treated as the standard definitions, regardless of context.
2669 * GDB now parses C++ symbol and type names more flexibly. For
2672 template<typename T> class C { };
2675 GDB will now correctly handle all of:
2677 ptype C<char const *>
2678 ptype C<char const*>
2679 ptype C<const char *>
2680 ptype C<const char*>
2682 * New features in the GDB remote stub, gdbserver
2684 - The "--wrapper" command-line argument tells gdbserver to use a
2685 wrapper program to launch programs for debugging.
2687 - On PowerPC and S/390 targets, it is now possible to use a single
2688 gdbserver executable to debug both 32-bit and 64-bit programs.
2689 (This requires gdbserver itself to be built as a 64-bit executable.)
2691 - gdbserver uses the new noack protocol mode for TCP connections to
2692 reduce communications latency, if also supported and enabled in GDB.
2694 - Support for the sparc64-linux-gnu target is now included in
2697 - The amd64-linux build of gdbserver now supports debugging both
2698 32-bit and 64-bit programs.
2700 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2701 now support hardware watchpoints, and will use them automatically
2706 GDB now has support for scripting using Python. Whether this is
2707 available is determined at configure time.
2709 New GDB commands can now be written in Python.
2711 * Ada tasking support
2713 Ada tasks can now be inspected in GDB. The following commands have
2717 Print the list of Ada tasks.
2719 Print detailed information about task number N.
2721 Print the task number of the current task.
2723 Switch the context of debugging to task number N.
2725 * Support for user-defined prefixed commands. The "define" command can
2726 add new commands to existing prefixes, e.g. "target".
2728 * Multi-inferior, multi-process debugging.
2730 GDB now has generalized support for multi-inferior debugging. See
2731 "Debugging Multiple Inferiors" in the manual for more information.
2732 Although availability still depends on target support, the command
2733 set is more uniform now. The GNU/Linux specific multi-forks support
2734 has been migrated to this new framework. This implied some user
2735 visible changes; see "New commands" and also "Removed commands"
2738 * Target descriptions can now describe the target OS ABI. See the
2739 "Target Description Format" section in the user manual for more
2742 * Target descriptions can now describe "compatible" architectures
2743 to indicate that the target can execute applications for a different
2744 architecture in addition to those for the main target architecture.
2745 See the "Target Description Format" section in the user manual for
2748 * Multi-architecture debugging.
2750 GDB now includes general supports for debugging applications on
2751 hybrid systems that use more than one single processor architecture
2752 at the same time. Each such hybrid architecture still requires
2753 specific support to be added. The only hybrid architecture supported
2754 in this version of GDB is the Cell Broadband Engine.
2756 * GDB now supports integrated debugging of Cell/B.E. applications that
2757 use both the PPU and SPU architectures. To enable support for hybrid
2758 Cell/B.E. debugging, you need to configure GDB to support both the
2759 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2760 --enable-targets configure option.
2762 * Non-stop mode debugging.
2764 For some targets, GDB now supports an optional mode of operation in
2765 which you can examine stopped threads while other threads continue
2766 to execute freely. This is referred to as non-stop mode, with the
2767 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2768 section in the user manual for more information.
2770 To be able to support remote non-stop debugging, a remote stub needs
2771 to implement the non-stop mode remote protocol extensions, as
2772 described in the "Remote Non-Stop" section of the user manual. The
2773 GDB remote stub, gdbserver, has been adjusted to support these
2774 extensions on linux targets.
2776 * New commands (for set/show, see "New options" below)
2778 catch syscall [NAME(S) | NUMBER(S)]
2779 Catch system calls. Arguments, which should be names of system
2780 calls or their numbers, mean catch only those syscalls. Without
2781 arguments, every syscall will be caught. When the inferior issues
2782 any of the specified syscalls, GDB will stop and announce the system
2783 call, both when it is called and when its call returns. This
2784 feature is currently available with a native GDB running on the
2785 Linux Kernel, under the following architectures: x86, x86_64,
2786 PowerPC and PowerPC64.
2788 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2790 Search memory for a sequence of bytes.
2792 maint set python print-stack
2793 maint show python print-stack
2794 Show a stack trace when an error is encountered in a Python script.
2797 Invoke CODE by passing it to the Python interpreter.
2802 These allow macros to be defined, undefined, and listed
2806 Show operating system information about processes.
2809 List the inferiors currently under GDB's control.
2812 Switch focus to inferior number NUM.
2815 Detach from inferior number NUM.
2818 Kill inferior number NUM.
2822 set spu stop-on-load
2823 show spu stop-on-load
2824 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2826 set spu auto-flush-cache
2827 show spu auto-flush-cache
2828 Control whether to automatically flush the software-managed cache
2829 during Cell/B.E. debugging.
2831 set sh calling-convention
2832 show sh calling-convention
2833 Control the calling convention used when calling SH target functions.
2836 show debug timestamp
2837 Control display of timestamps with GDB debugging output.
2839 set disassemble-next-line
2840 show disassemble-next-line
2841 Control display of disassembled source lines or instructions when
2844 set remote noack-packet
2845 show remote noack-packet
2846 Set/show the use of remote protocol QStartNoAckMode packet. See above
2847 under "New remote packets."
2849 set remote query-attached-packet
2850 show remote query-attached-packet
2851 Control use of remote protocol `qAttached' (query-attached) packet.
2853 set remote read-siginfo-object
2854 show remote read-siginfo-object
2855 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2858 set remote write-siginfo-object
2859 show remote write-siginfo-object
2860 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2863 set remote reverse-continue
2864 show remote reverse-continue
2865 Control use of remote protocol 'bc' (reverse-continue) packet.
2867 set remote reverse-step
2868 show remote reverse-step
2869 Control use of remote protocol 'bs' (reverse-step) packet.
2871 set displaced-stepping
2872 show displaced-stepping
2873 Control displaced stepping mode. Displaced stepping is a way to
2874 single-step over breakpoints without removing them from the debuggee.
2875 Also known as "out-of-line single-stepping".
2878 show debug displaced
2879 Control display of debugging info for displaced stepping.
2881 maint set internal-error
2882 maint show internal-error
2883 Control what GDB does when an internal error is detected.
2885 maint set internal-warning
2886 maint show internal-warning
2887 Control what GDB does when an internal warning is detected.
2892 Use a wrapper program to launch programs for debugging.
2894 set multiple-symbols (all|ask|cancel)
2895 show multiple-symbols
2896 The value of this variable can be changed to adjust the debugger behavior
2897 when an expression or a breakpoint location contains an ambiguous symbol
2898 name (an overloaded function name, for instance).
2900 set breakpoint always-inserted
2901 show breakpoint always-inserted
2902 Keep breakpoints always inserted in the target, as opposed to inserting
2903 them when resuming the target, and removing them when the target stops.
2904 This option can improve debugger performance on slow remote targets.
2906 set arm fallback-mode (arm|thumb|auto)
2907 show arm fallback-mode
2908 set arm force-mode (arm|thumb|auto)
2910 These commands control how ARM GDB determines whether instructions
2911 are ARM or Thumb. The default for both settings is auto, which uses
2912 the current CPSR value for instructions without symbols; previous
2913 versions of GDB behaved as if "set arm fallback-mode arm".
2915 set disable-randomization
2916 show disable-randomization
2917 Standalone programs run with the virtual address space randomization enabled
2918 by default on some platforms. This option keeps the addresses stable across
2919 multiple debugging sessions.
2923 Control whether other threads are stopped or not when some thread hits
2928 Requests that asynchronous execution is enabled in the target, if available.
2929 In this case, it's possible to resume target in the background, and interact
2930 with GDB while the target is running. "show target-async" displays the
2931 current state of asynchronous execution of the target.
2933 set target-wide-charset
2934 show target-wide-charset
2935 The target-wide-charset is the name of the character set that GDB
2936 uses when printing characters whose type is wchar_t.
2938 set tcp auto-retry (on|off)
2940 set tcp connect-timeout
2941 show tcp connect-timeout
2942 These commands allow GDB to retry failed TCP connections to a remote stub
2943 with a specified timeout period; this is useful if the stub is launched
2944 in parallel with GDB but may not be ready to accept connections immediately.
2946 set libthread-db-search-path
2947 show libthread-db-search-path
2948 Control list of directories which GDB will search for appropriate
2951 set schedule-multiple (on|off)
2952 show schedule-multiple
2953 Allow GDB to resume all threads of all processes or only threads of
2954 the current process.
2958 Use more aggressive caching for accesses to the stack. This improves
2959 performance of remote debugging (particularly backtraces) without
2960 affecting correctness.
2962 set interactive-mode (on|off|auto)
2963 show interactive-mode
2964 Control whether GDB runs in interactive mode (on) or not (off).
2965 When in interactive mode, GDB waits for the user to answer all
2966 queries. Otherwise, GDB does not wait and assumes the default
2967 answer. When set to auto (the default), GDB determines which
2968 mode to use based on the stdin settings.
2973 For program forks, this is replaced by the new more generic `info
2974 inferiors' command. To list checkpoints, you can still use the
2975 `info checkpoints' command, which was an alias for the `info forks'
2979 Replaced by the new `inferior' command. To switch between
2980 checkpoints, you can still use the `restart' command, which was an
2981 alias for the `fork' command.
2984 This is removed, since some targets don't have a notion of
2985 processes. To switch between processes, you can still use the
2986 `inferior' command using GDB's own inferior number.
2989 For program forks, this is replaced by the new more generic `kill
2990 inferior' command. To delete a checkpoint, you can still use the
2991 `delete checkpoint' command, which was an alias for the `delete
2995 For program forks, this is replaced by the new more generic `detach
2996 inferior' command. To detach a checkpoint, you can still use the
2997 `detach checkpoint' command, which was an alias for the `detach
3000 * New native configurations
3002 x86/x86_64 Darwin i[34567]86-*-darwin*
3004 x86_64 MinGW x86_64-*-mingw*
3008 Lattice Mico32 lm32-*
3009 x86 DICOS i[34567]86-*-dicos*
3010 x86_64 DICOS x86_64-*-dicos*
3013 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3014 (mingw32ce) debugging.
3020 These commands were actually not implemented on any target.
3022 *** Changes in GDB 6.8
3024 * New native configurations
3026 NetBSD/hppa hppa*-*netbsd*
3027 Xtensa GNU/Linux xtensa*-*-linux*
3031 NetBSD/hppa hppa*-*-netbsd*
3032 Xtensa GNU/Lunux xtensa*-*-linux*
3034 * Change in command line behavior -- corefiles vs. process ids.
3036 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3037 attaching to process NUMBER fails, GDB no longer attempts to open a
3038 core file named NUMBER. Attaching to a program using the -c option
3039 is no longer supported. Instead, use the '-p' or '--pid' options.
3041 * GDB can now be built as a native debugger for debugging Windows x86
3042 (mingw32) Portable Executable (PE) programs.
3044 * Pending breakpoints no longer change their number when their address
3047 * GDB now supports breakpoints with multiple locations,
3048 including breakpoints on C++ constructors, inside C++ templates,
3049 and in inlined functions.
3051 * GDB's ability to debug optimized code has been improved. GDB more
3052 accurately identifies function bodies and lexical blocks that occupy
3053 more than one contiguous range of addresses.
3055 * Target descriptions can now describe registers for PowerPC.
3057 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3058 registers on PowerPC targets.
3060 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3061 targets even when the libthread_db library is not available.
3063 * The GDB remote stub, gdbserver, now supports the new file transfer
3064 commands (remote put, remote get, and remote delete).
3066 * The GDB remote stub, gdbserver, now supports run and attach in
3067 extended-remote mode.
3069 * hppa*64*-*-hpux11* target broken
3070 The debugger is unable to start a program and fails with the following
3071 error: "Error trying to get information about dynamic linker".
3072 The gdb-6.7 release is also affected.
3074 * GDB now supports the --enable-targets= configure option to allow
3075 building a single GDB executable that supports multiple remote
3076 target architectures.
3078 * GDB now supports debugging C and C++ programs which use the
3079 Decimal Floating Point extension. In addition, the PowerPC target
3080 now has a set of pseudo-registers to inspect decimal float values
3081 stored in two consecutive float registers.
3083 * The -break-insert MI command can optionally create pending
3086 * Improved support for debugging Ada
3087 Many improvements to the Ada language support have been made. These
3089 - Better support for Ada2005 interface types
3090 - Improved handling of arrays and slices in general
3091 - Better support for Taft-amendment types
3092 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3094 - Improved command completion in Ada
3097 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3102 set print frame-arguments (all|scalars|none)
3103 show print frame-arguments
3104 The value of this variable can be changed to control which argument
3105 values should be printed by the debugger when displaying a frame.
3110 Transfer files to and from a remote target, and delete remote files.
3117 Transfer files to and from a remote target, and delete remote files.
3119 * New remote packets
3126 Open, close, read, write, and delete files on the remote system.
3129 Attach to an existing process on the remote system, in extended-remote
3133 Run a new process on the remote system, in extended-remote mode.
3135 *** Changes in GDB 6.7
3137 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3138 bfd, libiberty and opcodes, as revealed by static analysis donated by
3139 Coverity, Inc. (http://scan.coverity.com).
3141 * When looking up multiply-defined global symbols, GDB will now prefer the
3142 symbol definition in the current shared library if it was built using the
3143 -Bsymbolic linker option.
3145 * When the Text User Interface (TUI) is not configured, GDB will now
3146 recognize the -tui command-line option and print a message that the TUI
3149 * The GDB remote stub, gdbserver, now has lower overhead for high
3150 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3152 * GDB for MIPS targets now autodetects whether a remote target provides
3153 32-bit or 64-bit register values.
3155 * Support for C++ member pointers has been improved.
3157 * GDB now understands XML target descriptions, which specify the
3158 target's overall architecture. GDB can read a description from
3159 a local file or over the remote serial protocol.
3161 * Vectors of single-byte data use a new integer type which is not
3162 automatically displayed as character or string data.
3164 * The /s format now works with the print command. It displays
3165 arrays of single-byte integers and pointers to single-byte integers
3168 * Target descriptions can now describe target-specific registers,
3169 for architectures which have implemented the support (currently
3170 only ARM, M68K, and MIPS).
3172 * GDB and the GDB remote stub, gdbserver, now support the XScale
3175 * The GDB remote stub, gdbserver, has been updated to support
3176 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3177 has been rewritten to use the standard GDB remote protocol.
3179 * GDB can now step into C++ functions which are called through thunks.
3181 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3183 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3184 layout. It also supports a TextSeg= and DataSeg= response when only
3185 segment base addresses (rather than offsets) are available.
3187 * The /i format now outputs any trailing branch delay slot instructions
3188 immediately following the last instruction within the count specified.
3190 * The GDB remote protocol "T" stop reply packet now supports a
3191 "library" response. Combined with the new "qXfer:libraries:read"
3192 packet, this response allows GDB to debug shared libraries on targets
3193 where the operating system manages the list of loaded libraries (e.g.
3194 Windows and SymbianOS).
3196 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3197 (DLLs) on Windows and Windows CE targets.
3199 * GDB now supports a faster verification that a .debug file matches its binary
3200 according to its build-id signature, if the signature is present.
3206 Enable or disable hardware flow control (RTS/CTS) on the serial port
3207 when debugging using remote targets.
3209 set mem inaccessible-by-default
3210 show mem inaccessible-by-default
3211 If the target supplies a memory map, for instance via the remote
3212 protocol's "qXfer:memory-map:read" packet, setting this variable
3213 prevents GDB from accessing memory outside the memory map. This
3214 is useful for targets with memory mapped registers or which react
3215 badly to accesses of unmapped address space.
3217 set breakpoint auto-hw
3218 show breakpoint auto-hw
3219 If the target supplies a memory map, for instance via the remote
3220 protocol's "qXfer:memory-map:read" packet, setting this variable
3221 lets GDB use hardware breakpoints automatically for memory regions
3222 where it can not use software breakpoints. This covers both the
3223 "break" command and internal breakpoints used for other commands
3224 including "next" and "finish".
3227 catch exception unhandled
3228 Stop the program execution when Ada exceptions are raised.
3231 Stop the program execution when an Ada assertion failed.
3235 Set an alternate system root for target files. This is a more
3236 general version of "set solib-absolute-prefix", which is now
3237 an alias to "set sysroot".
3240 Provide extended SPU facility status information. This set of
3241 commands is available only when debugging the Cell/B.E. SPU
3244 * New native configurations
3246 OpenBSD/sh sh*-*openbsd*
3249 unset tdesc filename
3251 Use the specified local file as an XML target description, and do
3252 not query the target for its built-in description.
3256 OpenBSD/sh sh*-*-openbsd*
3257 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3258 Toshiba Media Processor mep-elf
3260 * New remote packets
3263 Ignore the specified signals; pass them directly to the debugged program
3264 without stopping other threads or reporting them to GDB.
3266 qXfer:features:read:
3267 Read an XML target description from the target, which describes its
3272 Read or write contents of an spufs file on the target system. These
3273 packets are available only on the Cell/B.E. SPU architecture.
3275 qXfer:libraries:read:
3276 Report the loaded shared libraries. Combined with new "T" packet
3277 response, this packet allows GDB to debug shared libraries on
3278 targets where the operating system manages the list of loaded
3279 libraries (e.g. Windows and SymbianOS).
3283 Support for these obsolete configurations has been removed.
3291 i[34567]86-*-lynxos*
3292 i[34567]86-*-netware*
3293 i[34567]86-*-sco3.2v5*
3294 i[34567]86-*-sco3.2v4*
3296 i[34567]86-*-sysv4.2*
3299 i[34567]86-*-unixware2*
3300 i[34567]86-*-unixware*
3309 * Other removed features
3316 Various m68k-only ROM monitors.
3323 Various Renesas ROM monitors and debugging interfaces for SH and
3328 Support for a Macraigor serial interface to on-chip debugging.
3329 GDB does not directly support the newer parallel or USB
3334 A debug information format. The predecessor to DWARF 2 and
3335 DWARF 3, which are still supported.
3337 Support for the HP aCC compiler on HP-UX/PA-RISC
3339 SOM-encapsulated symbolic debugging information, automatic
3340 invocation of pxdb, and the aCC custom C++ ABI. This does not
3341 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3342 with aCC can still be debugged on an assembly level.
3344 MIPS ".pdr" sections
3346 A MIPS-specific format used to describe stack frame layout
3347 in debugging information.
3351 GDB could work with an older version of Guile to debug
3352 the interpreter and Scheme programs running in it.
3354 set mips stack-arg-size
3355 set mips saved-gpreg-size
3357 Use "set mips abi" to control parameter passing for MIPS.
3359 *** Changes in GDB 6.6
3364 Cell Broadband Engine SPU spu-elf
3366 * GDB can now be configured as a cross-debugger targeting native Windows
3367 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3368 running on a Windows system over TCP/IP to debug Windows programs.
3370 * The GDB remote stub, gdbserver, has been updated to support Windows and
3371 Cygwin debugging. Both single-threaded and multi-threaded programs are
3374 * The "set trust-readonly-sections" command works again. This command was
3375 broken in GDB 6.3, 6.4, and 6.5.
3377 * The "load" command now supports writing to flash memory, if the remote
3378 stub provides the required support.
3380 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3381 longer requires symbolic debug information (e.g. DWARF-2).
3386 unset substitute-path
3387 show substitute-path
3388 Manage a list of substitution rules that GDB uses to rewrite the name
3389 of the directories where the sources are located. This can be useful
3390 for instance when the sources were moved to a different location
3391 between compilation and debugging.
3395 Print each CLI command as it is executed. Each command is prefixed with
3396 a number of `+' symbols representing the nesting depth.
3397 The source command now has a `-v' option to enable the same feature.
3401 The ARM Demon monitor support (RDP protocol, "target rdp").
3403 Kernel Object Display, an embedded debugging feature which only worked with
3404 an obsolete version of Cisco IOS.
3406 The 'set download-write-size' and 'show download-write-size' commands.
3408 * New remote packets
3411 Tell a stub about GDB client features, and request remote target features.
3412 The first feature implemented is PacketSize, which allows the target to
3413 specify the size of packets it can handle - to minimize the number of
3414 packets required and improve performance when connected to a remote
3418 Fetch an OS auxilliary vector from the remote stub. This packet is a
3419 more efficient replacement for qPart:auxv:read.
3421 qXfer:memory-map:read:
3422 Fetch a memory map from the remote stub, including information about
3423 RAM, ROM, and flash memory devices.
3428 Erase and program a flash memory device.
3430 * Removed remote packets
3433 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3434 used it, and only gdbserver implemented it.
3436 *** Changes in GDB 6.5
3440 Renesas M32C/M16C m32c-elf
3442 Morpho Technologies ms1 ms1-elf
3446 init-if-undefined Initialize a convenience variable, but
3447 only if it doesn't already have a value.
3449 The following commands are presently only implemented for native GNU/Linux:
3451 checkpoint Save a snapshot of the program state.
3453 restart <n> Return the program state to a
3454 previously saved state.
3456 info checkpoints List currently saved checkpoints.
3458 delete-checkpoint <n> Delete a previously saved checkpoint.
3460 set|show detach-on-fork Tell gdb whether to detach from a newly
3461 forked process, or to keep debugging it.
3463 info forks List forks of the user program that
3464 are available to be debugged.
3466 fork <n> Switch to debugging one of several
3467 forks of the user program that are
3468 available to be debugged.
3470 delete-fork <n> Delete a fork from the list of forks
3471 that are available to be debugged (and
3472 kill the forked process).
3474 detach-fork <n> Delete a fork from the list of forks
3475 that are available to be debugged (and
3476 allow the process to continue).
3480 Morpho Technologies ms2 ms1-elf
3482 * Improved Windows host support
3484 GDB now builds as a cross debugger hosted on i686-mingw32, including
3485 native console support, and remote communications using either
3486 network sockets or serial ports.
3488 * Improved Modula-2 language support
3490 GDB can now print most types in the Modula-2 syntax. This includes:
3491 basic types, set types, record types, enumerated types, range types,
3492 pointer types and ARRAY types. Procedure var parameters are correctly
3493 printed and hexadecimal addresses and character constants are also
3494 written in the Modula-2 syntax. Best results can be obtained by using
3495 GNU Modula-2 together with the -gdwarf-2 command line option.
3499 The ARM rdi-share module.
3501 The Netware NLM debug server.
3503 *** Changes in GDB 6.4
3505 * New native configurations
3507 OpenBSD/arm arm*-*-openbsd*
3508 OpenBSD/mips64 mips64-*-openbsd*
3512 Morpho Technologies ms1 ms1-elf
3514 * New command line options
3516 --batch-silent As for --batch, but totally silent.
3517 --return-child-result The debugger will exist with the same value
3518 the child (debugged) program exited with.
3519 --eval-command COMMAND, -ex COMMAND
3520 Execute a single GDB CLI command. This may be
3521 specified multiple times and in conjunction
3522 with the --command (-x) option.
3524 * Deprecated commands removed
3526 The following commands, that were deprecated in 2000, have been
3530 set|show arm disassembly-flavor set|show arm disassembler
3531 othernames set arm disassembler
3532 set|show remotedebug set|show debug remote
3533 set|show archdebug set|show debug arch
3534 set|show eventdebug set|show debug event
3537 * New BSD user-level threads support
3539 It is now possible to debug programs using the user-level threads
3540 library on OpenBSD and FreeBSD. Currently supported (target)
3543 FreeBSD/amd64 x86_64-*-freebsd*
3544 FreeBSD/i386 i386-*-freebsd*
3545 OpenBSD/i386 i386-*-openbsd*
3547 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3548 are not yet supported.
3550 * New support for Matsushita MN10300 w/sim added
3551 (Work in progress). mn10300-elf.
3553 * REMOVED configurations and files
3555 VxWorks and the XDR protocol *-*-vxworks
3556 Motorola MCORE mcore-*-*
3557 National Semiconductor NS32000 ns32k-*-*
3559 * New "set print array-indexes" command
3561 After turning this setting "on", GDB prints the index of each element
3562 when displaying arrays. The default is "off" to preserve the previous
3565 * VAX floating point support
3567 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3569 * User-defined command support
3571 In addition to using $arg0..$arg9 for argument passing, it is now possible
3572 to use $argc to determine now many arguments have been passed. See the
3573 section on user-defined commands in the user manual for more information.
3575 *** Changes in GDB 6.3:
3577 * New command line option
3579 GDB now accepts -l followed by a number to set the timeout for remote
3582 * GDB works with GCC -feliminate-dwarf2-dups
3584 GDB now supports a more compact representation of DWARF-2 debug
3585 information using DW_FORM_ref_addr references. These are produced
3586 by GCC with the option -feliminate-dwarf2-dups and also by some
3587 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3588 to use -feliminate-dwarf2-dups.
3590 * Internationalization
3592 When supported by the host system, GDB will be built with
3593 internationalization (libintl). The task of marking up the sources is
3594 continued, we're looking forward to our first translation.
3598 Initial support for debugging programs compiled with the GNAT
3599 implementation of the Ada programming language has been integrated
3600 into GDB. In this release, support is limited to expression evaluation.
3602 * New native configurations
3604 GNU/Linux/m32r m32r-*-linux-gnu
3608 GDB's remote protocol now includes support for the 'p' packet. This
3609 packet is used to fetch individual registers from a remote inferior.
3611 * END-OF-LIFE registers[] compatibility module
3613 GDB's internal register infrastructure has been completely rewritten.
3614 The new infrastructure making possible the implementation of key new
3615 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3618 GDB 6.3 will be the last release to include the the registers[]
3619 compatibility module that allowed out-of-date configurations to
3620 continue to work. This change directly impacts the following
3630 powerpc bdm protocol
3632 Unless there is activity to revive these configurations, they will be
3633 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3635 * OBSOLETE configurations and files
3637 Configurations that have been declared obsolete in this release have
3638 been commented out. Unless there is activity to revive these
3639 configurations, the next release of GDB will have their sources
3640 permanently REMOVED.
3649 *** Changes in GDB 6.2.1:
3651 * MIPS `break main; run' gave an heuristic-fence-post warning
3653 When attempting to run even a simple program, a warning about
3654 heuristic-fence-post being hit would be reported. This problem has
3657 * MIPS IRIX 'long double' crashed GDB
3659 When examining a long double variable, GDB would get a segmentation
3660 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3661 IRIX long double values).
3665 A bug in the VAX stack code was causing problems with the "next"
3666 command. This problem has been fixed.
3668 *** Changes in GDB 6.2:
3670 * Fix for ``many threads''
3672 On GNU/Linux systems that use the NPTL threads library, a program
3673 rapidly creating and deleting threads would confuse GDB leading to the
3676 ptrace: No such process.
3677 thread_db_get_info: cannot get thread info: generic error
3679 This problem has been fixed.
3681 * "-async" and "-noasync" options removed.
3683 Support for the broken "-noasync" option has been removed (it caused
3686 * New ``start'' command.
3688 This command runs the program until the begining of the main procedure.
3690 * New BSD Kernel Data Access Library (libkvm) interface
3692 Using ``target kvm'' it is now possible to debug kernel core dumps and
3693 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3694 platforms. Currently supported (native-only) configurations are:
3696 FreeBSD/amd64 x86_64-*-freebsd*
3697 FreeBSD/i386 i?86-*-freebsd*
3698 NetBSD/i386 i?86-*-netbsd*
3699 NetBSD/m68k m68*-*-netbsd*
3700 NetBSD/sparc sparc-*-netbsd*
3701 OpenBSD/amd64 x86_64-*-openbsd*
3702 OpenBSD/i386 i?86-*-openbsd*
3703 OpenBSD/m68k m68*-openbsd*
3704 OpenBSD/sparc sparc-*-openbsd*
3706 * Signal trampoline code overhauled
3708 Many generic problems with GDB's signal handling code have been fixed.
3709 These include: backtraces through non-contiguous stacks; recognition
3710 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3711 call; backtrace through a signal trampoline; step into and out of
3712 signal handlers; and single-stepping in the signal trampoline.
3714 Please note that kernel bugs are a limiting factor here. These
3715 features have been shown to work on an s390 GNU/Linux system that
3716 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3718 * Cygwin support for DWARF 2 added.
3720 * New native configurations
3722 GNU/Linux/hppa hppa*-*-linux*
3723 OpenBSD/hppa hppa*-*-openbsd*
3724 OpenBSD/m68k m68*-*-openbsd*
3725 OpenBSD/m88k m88*-*-openbsd*
3726 OpenBSD/powerpc powerpc-*-openbsd*
3727 NetBSD/vax vax-*-netbsd*
3728 OpenBSD/vax vax-*-openbsd*
3730 * END-OF-LIFE frame compatibility module
3732 GDB's internal frame infrastructure has been completely rewritten.
3733 The new infrastructure making it possible to support key new features
3734 including DWARF 2 Call Frame Information. To aid in the task of
3735 migrating old configurations to this new infrastructure, a
3736 compatibility module, that allowed old configurations to continue to
3737 work, was also included.
3739 GDB 6.2 will be the last release to include this frame compatibility
3740 module. This change directly impacts the following configurations:
3750 Unless there is activity to revive these configurations, they will be
3751 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3753 * REMOVED configurations and files
3755 Sun 3, running SunOS 3 m68*-*-sunos3*
3756 Sun 3, running SunOS 4 m68*-*-sunos4*
3757 Sun 2, running SunOS 3 m68000-*-sunos3*
3758 Sun 2, running SunOS 4 m68000-*-sunos4*
3759 Motorola 680x0 running LynxOS m68*-*-lynxos*
3760 AT&T 3b1/Unix pc m68*-att-*
3761 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3762 decstation mips-dec-* mips-little-*
3763 riscos mips-*-riscos* mips-*-sysv*
3764 sonymips mips-sony-*
3765 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3767 *** Changes in GDB 6.1.1:
3769 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3771 The TUI (Text-mode User Interface) is now built as part of a default
3772 GDB configuration. It is enabled by either selecting the TUI with the
3773 command line option "-i=tui" or by running the separate "gdbtui"
3774 program. For more information on the TUI, see the manual "Debugging
3777 * Pending breakpoint support (also included in GDB 6.1)
3779 Support has been added to allow you to specify breakpoints in shared
3780 libraries that have not yet been loaded. If a breakpoint location
3781 cannot be found, and the "breakpoint pending" option is set to auto,
3782 GDB queries you if you wish to make the breakpoint pending on a future
3783 shared-library load. If and when GDB resolves the breakpoint symbol,
3784 the pending breakpoint is removed as one or more regular breakpoints
3787 Pending breakpoints are very useful for GCJ Java debugging.
3789 * Fixed ISO-C build problems
3791 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3792 non ISO-C code that stopped them being built using a more strict ISO-C
3793 compiler (e.g., IBM's C compiler).
3795 * Fixed build problem on IRIX 5
3797 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3798 wasn't able to compile compile on an IRIX 5 system.
3800 * Added execute permission to gdb/gdbserver/configure
3802 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3803 permission. This bug would cause configure to fail on a number of
3804 systems (Solaris, IRIX). Ref: server/519.
3806 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3808 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3809 has been updated to use constant array sizes.
3811 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3813 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3814 its generated DWARF Call Frame Info. This encoding was causing GDB to
3815 panic, that panic has been fixed. Ref: gdb/1628.
3817 * Fixed a problem when examining parameters in shared library code.
3819 When examining parameters in optimized shared library code generated
3820 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3821 not available''. GDB now correctly displays the variable's value.
3823 *** Changes in GDB 6.1:
3825 * Removed --with-mmalloc
3827 Support for the mmalloc memory manager has been removed, as it
3828 conflicted with the internal gdb byte cache.
3830 * Changes in AMD64 configurations
3832 The AMD64 target now includes the %cs and %ss registers. As a result
3833 the AMD64 remote protocol has changed; this affects the floating-point
3834 and SSE registers. If you rely on those registers for your debugging,
3835 you should upgrade gdbserver on the remote side.
3837 * Revised SPARC target
3839 The SPARC target has been completely revised, incorporating the
3840 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3841 support for LynxOS and SunOS 4 has been dropped. Calling functions
3842 from within GDB on operating systems with a non-executable stack
3843 (Solaris, OpenBSD) now works.
3847 GDB has a new C++ demangler which does a better job on the mangled
3848 names generated by current versions of g++. It also runs faster, so
3849 with this and other changes gdb should now start faster on large C++
3852 * DWARF 2 Location Expressions
3854 GDB support for location expressions has been extended to support function
3855 arguments and frame bases. Older versions of GDB could crash when they
3858 * C++ nested types and namespaces
3860 GDB's support for nested types and namespaces in C++ has been
3861 improved, especially if you use the DWARF 2 debugging format. (This
3862 is the default for recent versions of GCC on most platforms.)
3863 Specifically, if you have a class "Inner" defined within a class or
3864 namespace "Outer", then GDB realizes that the class's name is
3865 "Outer::Inner", not simply "Inner". This should greatly reduce the
3866 frequency of complaints about not finding RTTI symbols. In addition,
3867 if you are stopped at inside of a function defined within a namespace,
3868 GDB modifies its name lookup accordingly.
3870 * New native configurations
3872 NetBSD/amd64 x86_64-*-netbsd*
3873 OpenBSD/amd64 x86_64-*-openbsd*
3874 OpenBSD/alpha alpha*-*-openbsd*
3875 OpenBSD/sparc sparc-*-openbsd*
3876 OpenBSD/sparc64 sparc64-*-openbsd*
3878 * New debugging protocols
3880 M32R with SDI protocol m32r-*-elf*
3882 * "set prompt-escape-char" command deleted.
3884 The command "set prompt-escape-char" has been deleted. This command,
3885 and its very obscure effet on GDB's prompt, was never documented,
3886 tested, nor mentioned in the NEWS file.
3888 * OBSOLETE configurations and files
3890 Configurations that have been declared obsolete in this release have
3891 been commented out. Unless there is activity to revive these
3892 configurations, the next release of GDB will have their sources
3893 permanently REMOVED.
3895 Sun 3, running SunOS 3 m68*-*-sunos3*
3896 Sun 3, running SunOS 4 m68*-*-sunos4*
3897 Sun 2, running SunOS 3 m68000-*-sunos3*
3898 Sun 2, running SunOS 4 m68000-*-sunos4*
3899 Motorola 680x0 running LynxOS m68*-*-lynxos*
3900 AT&T 3b1/Unix pc m68*-att-*
3901 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3902 decstation mips-dec-* mips-little-*
3903 riscos mips-*-riscos* mips-*-sysv*
3904 sonymips mips-sony-*
3905 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3907 * REMOVED configurations and files
3909 SGI Irix-4.x mips-sgi-irix4 or iris4
3910 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3911 Z8000 simulator z8k-zilog-none or z8ksim
3912 Matsushita MN10200 w/simulator mn10200-*-*
3913 H8/500 simulator h8500-hitachi-hms or h8500hms
3914 HP/PA running BSD hppa*-*-bsd*
3915 HP/PA running OSF/1 hppa*-*-osf*
3916 HP/PA Pro target hppa*-*-pro*
3917 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3918 386BSD i[3456]86-*-bsd*
3919 Sequent family i[3456]86-sequent-sysv4*
3920 i[3456]86-sequent-sysv*
3921 i[3456]86-sequent-bsd*
3922 SPARC running LynxOS sparc-*-lynxos*
3923 SPARC running SunOS 4 sparc-*-sunos4*
3924 Tsqware Sparclet sparclet-*-*
3925 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3927 *** Changes in GDB 6.0:
3931 Support for debugging the Objective-C programming language has been
3932 integrated into GDB.
3934 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3936 DWARF 2's Call Frame Information makes available compiler generated
3937 information that more exactly describes the program's run-time stack.
3938 By using this information, GDB is able to provide more robust stack
3941 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3942 have been updated to use a new backtrace mechanism which includes
3943 DWARF 2 CFI support.
3947 GDB's remote protocol has been extended to include support for hosted
3948 file I/O (where the remote target uses GDB's file system). See GDB's
3949 remote protocol documentation for details.
3951 * All targets using the new architecture framework.
3953 All of GDB's targets have been updated to use the new internal
3954 architecture framework. The way is now open for future GDB releases
3955 to include cross-architecture native debugging support (i386 on amd64,
3958 * GNU/Linux's Thread Local Storage (TLS)
3960 GDB now includes support for for the GNU/Linux implementation of
3961 per-thread variables.
3963 * GNU/Linux's Native POSIX Thread Library (NPTL)
3965 GDB's thread code has been updated to work with either the new
3966 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3968 * Separate debug info.
3970 GDB, in conjunction with BINUTILS, now supports a mechanism for
3971 automatically loading debug information from a separate file. Instead
3972 of shipping full debug and non-debug versions of system libraries,
3973 system integrators can now instead ship just the stripped libraries
3974 and optional debug files.
3976 * DWARF 2 Location Expressions
3978 DWARF 2 Location Expressions allow the compiler to more completely
3979 describe the location of variables (even in optimized code) to the
3982 GDB now includes preliminary support for location expressions (support
3983 for DW_OP_piece is still missing).
3987 A number of long standing bugs that caused GDB to die while starting a
3988 Java application have been fixed. GDB's Java support is now
3989 considered "useable".
3991 * GNU/Linux support for fork, vfork, and exec.
3993 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3994 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3997 * GDB supports logging output to a file
3999 There are two new commands, "set logging" and "show logging", which can be
4000 used to capture GDB's output to a file.
4002 * The meaning of "detach" has changed for gdbserver
4004 The "detach" command will now resume the application, as documented. To
4005 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4008 * d10v, m68hc11 `regs' command deprecated
4010 The `info registers' command has been updated so that it displays the
4011 registers using a format identical to the old `regs' command.
4015 A new command, "maint set profile on/off", has been added. This command can
4016 be used to enable or disable profiling while running GDB, to profile a
4017 session or a set of commands. In addition there is a new configure switch,
4018 "--enable-profiling", which will cause GDB to be compiled with profiling
4019 data, for more informative profiling results.
4021 * Default MI syntax changed to "mi2".
4023 The default MI (machine interface) syntax, enabled by the command line
4024 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4025 "mi1", can be enabled by specifying the option "-i=mi1".
4027 Support for the original "mi0" syntax (included in GDB 5.0) has been
4030 Fix for gdb/192: removed extraneous space when displaying frame level.
4031 Fix for gdb/672: update changelist is now output in mi list format.
4032 Fix for gdb/702: a -var-assign that updates the value now shows up
4033 in a subsequent -var-update.
4035 * New native configurations.
4037 FreeBSD/amd64 x86_64-*-freebsd*
4039 * Multi-arched targets.
4041 HP/PA HPUX11 hppa*-*-hpux*
4042 Renesas M32R/D w/simulator m32r-*-elf*
4044 * OBSOLETE configurations and files
4046 Configurations that have been declared obsolete in this release have
4047 been commented out. Unless there is activity to revive these
4048 configurations, the next release of GDB will have their sources
4049 permanently REMOVED.
4051 Z8000 simulator z8k-zilog-none or z8ksim
4052 Matsushita MN10200 w/simulator mn10200-*-*
4053 H8/500 simulator h8500-hitachi-hms or h8500hms
4054 HP/PA running BSD hppa*-*-bsd*
4055 HP/PA running OSF/1 hppa*-*-osf*
4056 HP/PA Pro target hppa*-*-pro*
4057 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4058 Sequent family i[3456]86-sequent-sysv4*
4059 i[3456]86-sequent-sysv*
4060 i[3456]86-sequent-bsd*
4061 Tsqware Sparclet sparclet-*-*
4062 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4064 * REMOVED configurations and files
4067 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4068 IBM AIX PS/2 i[3456]86-*-aix
4069 i386 running Mach 3.0 i[3456]86-*-mach3*
4070 i386 running Mach i[3456]86-*-mach*
4071 i386 running OSF/1 i[3456]86-*osf1mk*
4072 HP/Apollo 68k Family m68*-apollo*-sysv*,
4074 m68*-hp-bsd*, m68*-hp-hpux*
4075 Argonaut Risc Chip (ARC) arc-*-*
4076 Mitsubishi D30V d30v-*-*
4077 Fujitsu FR30 fr30-*-elf*
4078 OS/9000 i[34]86-*-os9k
4079 I960 with MON960 i960-*-coff
4081 * MIPS $fp behavior changed
4083 The convenience variable $fp, for the MIPS, now consistently returns
4084 the address of the current frame's base. Previously, depending on the
4085 context, $fp could refer to either $sp or the current frame's base
4086 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4087 The GNU Source-Level Debugger''.
4089 *** Changes in GDB 5.3:
4091 * GNU/Linux shared library multi-threaded performance improved.
4093 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4094 `/proc', in preference to `ptrace' for memory reads. This may result
4095 in an improvement in the start-up time of multi-threaded, shared
4096 library applications when run under GDB. One GDB user writes: ``loads
4097 shared libs like mad''.
4099 * ``gdbserver'' now supports multi-threaded applications on some targets
4101 Support for debugging multi-threaded applications which use
4102 the GNU/Linux LinuxThreads package has been added for
4103 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4104 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4106 * GDB now supports C/C++ preprocessor macros.
4108 GDB now expands preprocessor macro invocations in C/C++ expressions,
4109 and provides various commands for showing macro definitions and how
4112 The new command `macro expand EXPRESSION' expands any macro
4113 invocations in expression, and shows the result.
4115 The new command `show macro MACRO-NAME' shows the definition of the
4116 macro named MACRO-NAME, and where it was defined.
4118 Most compilers don't include information about macros in the debugging
4119 information by default. In GCC 3.1, for example, you need to compile
4120 your program with the options `-gdwarf-2 -g3'. If the macro
4121 information is present in the executable, GDB will read it.
4123 * Multi-arched targets.
4125 DEC Alpha (partial) alpha*-*-*
4126 DEC VAX (partial) vax-*-*
4128 National Semiconductor NS32000 (partial) ns32k-*-*
4129 Motorola 68000 (partial) m68k-*-*
4130 Motorola MCORE mcore-*-*
4134 Fujitsu FRV architecture added by Red Hat frv*-*-*
4137 * New native configurations
4139 Alpha NetBSD alpha*-*-netbsd*
4140 SH NetBSD sh*-*-netbsdelf*
4141 MIPS NetBSD mips*-*-netbsd*
4142 UltraSPARC NetBSD sparc64-*-netbsd*
4144 * OBSOLETE configurations and files
4146 Configurations that have been declared obsolete in this release have
4147 been commented out. Unless there is activity to revive these
4148 configurations, the next release of GDB will have their sources
4149 permanently REMOVED.
4151 Mitsubishi D30V d30v-*-*
4152 OS/9000 i[34]86-*-os9k
4153 IBM AIX PS/2 i[3456]86-*-aix
4154 Fujitsu FR30 fr30-*-elf*
4155 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4156 Argonaut Risc Chip (ARC) arc-*-*
4157 i386 running Mach 3.0 i[3456]86-*-mach3*
4158 i386 running Mach i[3456]86-*-mach*
4159 i386 running OSF/1 i[3456]86-*osf1mk*
4160 HP/Apollo 68k Family m68*-apollo*-sysv*,
4162 m68*-hp-bsd*, m68*-hp-hpux*
4163 I960 with MON960 i960-*-coff
4165 * OBSOLETE languages
4167 CHILL, a Pascal like language used by telecommunications companies.
4169 * REMOVED configurations and files
4171 AMD 29k family via UDI a29k-amd-udi, udi29k
4172 A29K VxWorks a29k-*-vxworks
4173 AMD 29000 embedded, using EBMON a29k-none-none
4174 AMD 29000 embedded with COFF a29k-none-coff
4175 AMD 29000 embedded with a.out a29k-none-aout
4177 testsuite/gdb.hp/gdb.threads-hp/ directory
4179 * New command "set max-user-call-depth <nnn>"
4181 This command allows the user to limit the call depth of user-defined
4182 commands. The default is 1024.
4184 * Changes in FreeBSD/i386 native debugging.
4186 Support for the "generate-core-file" has been added.
4188 * New commands "dump", "append", and "restore".
4190 These commands allow data to be copied from target memory
4191 to a bfd-format or binary file (dump and append), and back
4192 from a file into memory (restore).
4194 * Improved "next/step" support on multi-processor Alpha Tru64.
4196 The previous single-step mechanism could cause unpredictable problems,
4197 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4198 of a software single-step mechanism prevents this.
4200 *** Changes in GDB 5.2.1:
4208 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4209 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4210 Fix, by Joel Brobecker imported from mainline.
4212 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4213 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4214 Fix, by Fred Fish, imported from mainline.
4216 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4217 Surprisingly enough, it works now.
4218 By Michal Ludvig, imported from mainline.
4220 i386 hardware watchpoint support:
4221 avoid misses on second run for some targets.
4222 By Pierre Muller, imported from mainline.
4224 *** Changes in GDB 5.2:
4226 * New command "set trust-readonly-sections on[off]".
4228 This command is a hint that tells gdb that read-only sections
4229 really are read-only (ie. that their contents will not change).
4230 In this mode, gdb will go to the object file rather than the
4231 target to read memory from read-only sections (such as ".text").
4232 This can be a significant performance improvement on some
4233 (notably embedded) targets.
4235 * New command "generate-core-file" (or "gcore").
4237 This new gdb command allows the user to drop a core file of the child
4238 process state at any time. So far it's been implemented only for
4239 GNU/Linux and Solaris, but should be relatively easily ported to other
4240 hosts. Argument is core file name (defaults to core.<pid>).
4242 * New command line option
4244 GDB now accepts --pid or -p followed by a process id.
4246 * Change in command line behavior -- corefiles vs. process ids.
4248 There is a subtle behavior in the way in which GDB handles
4249 command line arguments. The first non-flag argument is always
4250 a program to debug, but the second non-flag argument may either
4251 be a corefile or a process id. Previously, GDB would attempt to
4252 open the second argument as a corefile, and if that failed, would
4253 issue a superfluous error message and then attempt to attach it as
4254 a process. Now, if the second argument begins with a non-digit,
4255 it will be treated as a corefile. If it begins with a digit,
4256 GDB will attempt to attach it as a process, and if no such process
4257 is found, will then attempt to open it as a corefile.
4259 * Changes in ARM configurations.
4261 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4262 configuration is fully multi-arch.
4264 * New native configurations
4266 ARM NetBSD arm*-*-netbsd*
4267 x86 OpenBSD i[3456]86-*-openbsd*
4268 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4269 Sparc64 running FreeBSD sparc64-*-freebsd*
4273 Sanyo XStormy16 xstormy16-elf
4275 * OBSOLETE configurations and files
4277 Configurations that have been declared obsolete in this release have
4278 been commented out. Unless there is activity to revive these
4279 configurations, the next release of GDB will have their sources
4280 permanently REMOVED.
4282 AMD 29k family via UDI a29k-amd-udi, udi29k
4283 A29K VxWorks a29k-*-vxworks
4284 AMD 29000 embedded, using EBMON a29k-none-none
4285 AMD 29000 embedded with COFF a29k-none-coff
4286 AMD 29000 embedded with a.out a29k-none-aout
4288 testsuite/gdb.hp/gdb.threads-hp/ directory
4290 * REMOVED configurations and files
4292 TI TMS320C80 tic80-*-*
4294 PowerPC Solaris powerpcle-*-solaris*
4295 PowerPC Windows NT powerpcle-*-cygwin32
4296 PowerPC Netware powerpc-*-netware*
4297 Harris/CXUX m88k m88*-harris-cxux*
4298 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4299 ns32k-utek-sysv* ns32k-utek-*
4300 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4301 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4302 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4303 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4304 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4306 * Changes to command line processing
4308 The new `--args' feature can be used to specify command-line arguments
4309 for the inferior from gdb's command line.
4311 * Changes to key bindings
4313 There is a new `operate-and-get-next' function bound to `C-o'.
4315 *** Changes in GDB 5.1.1
4317 Fix compile problem on DJGPP.
4319 Fix a problem with floating-point registers on the i386 being
4322 Fix to stop GDB crashing on .debug_str debug info.
4324 Numerous documentation fixes.
4326 Numerous testsuite fixes.
4328 *** Changes in GDB 5.1:
4330 * New native configurations
4332 Alpha FreeBSD alpha*-*-freebsd*
4333 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4334 MIPS GNU/Linux mips*-*-linux*
4335 MIPS SGI Irix 6.x mips*-sgi-irix6*
4336 ia64 AIX ia64-*-aix*
4337 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4341 Motorola 68HC11 and 68HC12 m68hc11-elf
4343 UltraSparc running GNU/Linux sparc64-*-linux*
4345 * OBSOLETE configurations and files
4347 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4348 Harris/CXUX m88k m88*-harris-cxux*
4349 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4350 ns32k-utek-sysv* ns32k-utek-*
4351 TI TMS320C80 tic80-*-*
4353 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4354 PowerPC Solaris powerpcle-*-solaris*
4355 PowerPC Windows NT powerpcle-*-cygwin32
4356 PowerPC Netware powerpc-*-netware*
4357 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4358 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4359 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4360 Apple Macintosh (MPW) host N/A
4362 stuff.c (Program to stuff files into a specially prepared space in kdb)
4363 kdb-start.c (Main loop for the standalone kernel debugger)
4365 Configurations that have been declared obsolete in this release have
4366 been commented out. Unless there is activity to revive these
4367 configurations, the next release of GDB will have their sources
4368 permanently REMOVED.
4370 * REMOVED configurations and files
4372 Altos 3068 m68*-altos-*
4373 Convex c1-*-*, c2-*-*
4375 ARM RISCix arm-*-* (as host)
4379 * GDB has been converted to ISO C.
4381 GDB's source code has been converted to ISO C. In particular, the
4382 sources are fully protoized, and rely on standard headers being
4387 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4389 * The MI enabled by default.
4391 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4392 revised and enabled by default. Packages which use GDB as a debugging
4393 engine behind a UI or another front end are encouraged to switch to
4394 using the GDB/MI interface, instead of the old annotations interface
4395 which is now deprecated.
4397 * Support for debugging Pascal programs.
4399 GDB now includes support for debugging Pascal programs. The following
4400 main features are supported:
4402 - Pascal-specific data types such as sets;
4404 - automatic recognition of Pascal sources based on file-name
4407 - Pascal-style display of data types, variables, and functions;
4409 - a Pascal expression parser.
4411 However, some important features are not yet supported.
4413 - Pascal string operations are not supported at all;
4415 - there are some problems with boolean types;
4417 - Pascal type hexadecimal constants are not supported
4418 because they conflict with the internal variables format;
4420 - support for Pascal objects and classes is not full yet;
4422 - unlike Pascal, GDB is case-sensitive for symbol names.
4424 * Changes in completion.
4426 Commands such as `shell', `run' and `set args', which pass arguments
4427 to inferior programs, now complete on file names, similar to what
4428 users expect at the shell prompt.
4430 Commands which accept locations, such as `disassemble', `print',
4431 `breakpoint', `until', etc. now complete on filenames as well as
4432 program symbols. Thus, if you type "break foob TAB", and the source
4433 files linked into the programs include `foobar.c', that file name will
4434 be one of the candidates for completion. However, file names are not
4435 considered for completion after you typed a colon that delimits a file
4436 name from a name of a function in that file, as in "break foo.c:bar".
4438 `set demangle-style' completes on available demangling styles.
4440 * New platform-independent commands:
4442 It is now possible to define a post-hook for a command as well as a
4443 hook that runs before the command. For more details, see the
4444 documentation of `hookpost' in the GDB manual.
4446 * Changes in GNU/Linux native debugging.
4448 Support for debugging multi-threaded programs has been completely
4449 revised for all platforms except m68k and sparc. You can now debug as
4450 many threads as your system allows you to have.
4452 Attach/detach is supported for multi-threaded programs.
4454 Support for SSE registers was added for x86. This doesn't work for
4455 multi-threaded programs though.
4457 * Changes in MIPS configurations.
4459 Multi-arch support is enabled for all MIPS configurations.
4461 GDB can now be built as native debugger on SGI Irix 6.x systems for
4462 debugging n32 executables. (Debugging 64-bit executables is not yet
4465 * Unified support for hardware watchpoints in all x86 configurations.
4467 Most (if not all) native x86 configurations support hardware-assisted
4468 breakpoints and watchpoints in a unified manner. This support
4469 implements debug register sharing between watchpoints, which allows to
4470 put a virtually infinite number of watchpoints on the same address,
4471 and also supports watching regions up to 16 bytes with several debug
4474 The new maintenance command `maintenance show-debug-regs' toggles
4475 debugging print-outs in functions that insert, remove, and test
4476 watchpoints and hardware breakpoints.
4478 * Changes in the DJGPP native configuration.
4480 New command ``info dos sysinfo'' displays assorted information about
4481 the CPU, OS, memory, and DPMI server.
4483 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4484 display information about segment descriptors stored in GDT, LDT, and
4487 New commands ``info dos pde'' and ``info dos pte'' display entries
4488 from Page Directory and Page Tables (for now works with CWSDPMI only).
4489 New command ``info dos address-pte'' displays the Page Table entry for
4490 a given linear address.
4492 GDB can now pass command lines longer than 126 characters to the
4493 program being debugged (requires an update to the libdbg.a library
4494 which is part of the DJGPP development kit).
4496 DWARF2 debug info is now supported.
4498 It is now possible to `step' and `next' through calls to `longjmp'.
4500 * Changes in documentation.
4502 All GDB documentation was converted to GFDL, the GNU Free
4503 Documentation License.
4505 Tracepoints-related commands are now fully documented in the GDB
4508 TUI, the Text-mode User Interface, is now documented in the manual.
4510 Tracepoints-related commands are now fully documented in the GDB
4513 The "GDB Internals" manual now has an index. It also includes
4514 documentation of `ui_out' functions, GDB coding standards, x86
4515 hardware watchpoints, and memory region attributes.
4517 * GDB's version number moved to ``version.in''
4519 The Makefile variable VERSION has been replaced by the file
4520 ``version.in''. People creating GDB distributions should update the
4521 contents of this file.
4525 GUD support is now a standard part of the EMACS distribution.
4527 *** Changes in GDB 5.0:
4529 * Improved support for debugging FP programs on x86 targets
4531 Unified and much-improved support for debugging floating-point
4532 programs on all x86 targets. In particular, ``info float'' now
4533 displays the FP registers in the same format on all x86 targets, with
4534 greater level of detail.
4536 * Improvements and bugfixes in hardware-assisted watchpoints
4538 It is now possible to watch array elements, struct members, and
4539 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4540 on x86 targets no longer erroneously trigger when the address is
4543 * Improvements in the native DJGPP version of GDB
4545 The distribution now includes all the scripts and auxiliary files
4546 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4547 machines ``out of the box''.
4549 The DJGPP version can now debug programs that use signals. It is
4550 possible to catch signals that happened in the debuggee, deliver
4551 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4552 would kill the program being debugged.) Programs that hook hardware
4553 interrupts (keyboard, timer, etc.) can also be debugged.
4555 It is now possible to debug DJGPP programs that redirect their
4556 standard handles or switch them to raw (as opposed to cooked) mode, or
4557 even close them. The command ``run < foo > bar'' works as expected,
4558 and ``info terminal'' reports useful information about the debuggee's
4559 terminal, including raw/cooked mode, redirection, etc.
4561 The DJGPP version now uses termios functions for console I/O, which
4562 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4565 DOS-style file names with drive letters are now fully supported by
4568 It is now possible to debug DJGPP programs that switch their working
4569 directory. It is also possible to rerun the debuggee any number of
4570 times without restarting GDB; thus, you can use the same setup,
4571 breakpoints, etc. for many debugging sessions.
4573 * New native configurations
4575 ARM GNU/Linux arm*-*-linux*
4576 PowerPC GNU/Linux powerpc-*-linux*
4580 Motorola MCore mcore-*-*
4581 x86 VxWorks i[3456]86-*-vxworks*
4582 PowerPC VxWorks powerpc-*-vxworks*
4583 TI TMS320C80 tic80-*-*
4585 * OBSOLETE configurations
4587 Altos 3068 m68*-altos-*
4588 Convex c1-*-*, c2-*-*
4590 ARM RISCix arm-*-* (as host)
4593 Configurations that have been declared obsolete will be commented out,
4594 but the code will be left in place. If there is no activity to revive
4595 these configurations before the next release of GDB, the sources will
4596 be permanently REMOVED.
4598 * Gould support removed
4600 Support for the Gould PowerNode and NP1 has been removed.
4602 * New features for SVR4
4604 On SVR4 native platforms (such as Solaris), if you attach to a process
4605 without first loading a symbol file, GDB will now attempt to locate and
4606 load symbols from the running process's executable file.
4608 * Many C++ enhancements
4610 C++ support has been greatly improved. Overload resolution now works properly
4611 in almost all cases. RTTI support is on the way.
4613 * Remote targets can connect to a sub-program
4615 A popen(3) style serial-device has been added. This device starts a
4616 sub-process (such as a stand-alone simulator) and then communicates
4617 with that. The sub-program to run is specified using the syntax
4618 ``|<program> <args>'' vis:
4620 (gdb) set remotedebug 1
4621 (gdb) target extended-remote |mn10300-elf-sim program-args
4623 * MIPS 64 remote protocol
4625 A long standing bug in the mips64 remote protocol where by GDB
4626 expected certain 32 bit registers (ex SR) to be transfered as 32
4627 instead of 64 bits has been fixed.
4629 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4630 added to provide backward compatibility with older versions of GDB.
4632 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4634 The command ``set remotebinarydownload'' command has been replaced by
4635 ``set remote X-packet''. Other commands in ``set remote'' family
4636 include ``set remote P-packet''.
4638 * Breakpoint commands accept ranges.
4640 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4641 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4642 ``tracepoint passcount'' also accepts a range of tracepoints.
4644 * ``apropos'' command added.
4646 The ``apropos'' command searches through command names and
4647 documentation strings, printing out matches, making it much easier to
4648 try to find a command that does what you are looking for.
4652 A new machine oriented interface (MI) has been added to GDB. This
4653 interface is designed for debug environments running GDB as a separate
4654 process. This is part of the long term libGDB project. See the
4655 "GDB/MI" chapter of the GDB manual for further information. It can be
4656 enabled by configuring with:
4658 .../configure --enable-gdbmi
4660 *** Changes in GDB-4.18:
4662 * New native configurations
4664 HP-UX 10.20 hppa*-*-hpux10.20
4665 HP-UX 11.x hppa*-*-hpux11.0*
4666 M68K GNU/Linux m68*-*-linux*
4670 Fujitsu FR30 fr30-*-elf*
4671 Intel StrongARM strongarm-*-*
4672 Mitsubishi D30V d30v-*-*
4674 * OBSOLETE configurations
4676 Gould PowerNode, NP1 np1-*-*, pn-*-*
4678 Configurations that have been declared obsolete will be commented out,
4679 but the code will be left in place. If there is no activity to revive
4680 these configurations before the next release of GDB, the sources will
4681 be permanently REMOVED.
4685 As a compatibility experiment, GDB's source files buildsym.h and
4686 buildsym.c have been converted to pure standard C, no longer
4687 containing any K&R compatibility code. We believe that all systems in
4688 use today either come with a standard C compiler, or have a GCC port
4689 available. If this is not true, please report the affected
4690 configuration to bug-gdb@gnu.org immediately. See the README file for
4691 information about getting a standard C compiler if you don't have one
4696 GDB now uses readline 2.2.
4698 * set extension-language
4700 You can now control the mapping between filename extensions and source
4701 languages by using the `set extension-language' command. For instance,
4702 you can ask GDB to treat .c files as C++ by saying
4703 set extension-language .c c++
4704 The command `info extensions' lists all of the recognized extensions
4705 and their associated languages.
4707 * Setting processor type for PowerPC and RS/6000
4709 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4710 you can use the `set processor' command to specify what variant of the
4711 PowerPC family you are debugging. The command
4715 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4716 following PowerPC and RS6000 variants:
4718 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4719 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4721 403GC IBM PowerPC 403GC
4722 505 Motorola PowerPC 505
4723 860 Motorola PowerPC 860 or 850
4724 601 Motorola PowerPC 601
4725 602 Motorola PowerPC 602
4726 603 Motorola/IBM PowerPC 603 or 603e
4727 604 Motorola PowerPC 604 or 604e
4728 750 Motorola/IBM PowerPC 750 or 750
4730 At the moment, this command just tells GDB what to name the
4731 special-purpose processor registers. Since almost all the affected
4732 registers are inaccessible to user-level programs, this command is
4733 only useful for remote debugging in its present form.
4737 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4738 more extensive support for HP-UX. Added features include shared
4739 library support, kernel threads and hardware watchpoints for 11.00,
4740 support for HP's ANSI C and C++ compilers, and a compatibility mode
4741 for xdb and dbx commands.
4745 HP's donation includes the new concept of catchpoints, which is a
4746 generalization of the old catch command. On HP-UX, it is now possible
4747 to catch exec, fork, and vfork, as well as library loading.
4749 This means that the existing catch command has changed; its first
4750 argument now specifies the type of catch to be set up. See the
4751 output of "help catch" for a list of catchpoint types.
4753 * Debugging across forks
4755 On HP-UX, you can choose which process to debug when a fork() happens
4760 HP has donated a curses-based terminal user interface (TUI). To get
4761 it, build with --enable-tui. Although this can be enabled for any
4762 configuration, at present it only works for native HP debugging.
4764 * GDB remote protocol additions
4766 A new protocol packet 'X' that writes binary data is now available.
4767 Default behavior is to try 'X', then drop back to 'M' if the stub
4768 fails to respond. The settable variable `remotebinarydownload'
4769 allows explicit control over the use of 'X'.
4771 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4772 full 64-bit address. The command
4774 set remoteaddresssize 32
4776 can be used to revert to the old behaviour. For existing remote stubs
4777 the change should not be noticed, as the additional address information
4780 In order to assist in debugging stubs, you may use the maintenance
4781 command `packet' to send any text string to the stub. For instance,
4783 maint packet heythere
4785 sends the packet "$heythere#<checksum>". Note that it is very easy to
4786 disrupt a debugging session by sending the wrong packet at the wrong
4789 The compare-sections command allows you to compare section data on the
4790 target to what is in the executable file without uploading or
4791 downloading, by comparing CRC checksums.
4793 * Tracing can collect general expressions
4795 You may now collect general expressions at tracepoints. This requires
4796 further additions to the target-side stub; see tracepoint.c and
4797 doc/agentexpr.texi for further details.
4799 * mask-address variable for Mips
4801 For Mips targets, you may control the zeroing of the upper 32 bits of
4802 a 64-bit address by entering `set mask-address on'. This is mainly
4803 of interest to users of embedded R4xxx and R5xxx processors.
4805 * Higher serial baud rates
4807 GDB's serial code now allows you to specify baud rates 57600, 115200,
4808 230400, and 460800 baud. (Note that your host system may not be able
4809 to achieve all of these rates.)
4813 The i960 configuration now includes an initial implementation of a
4814 builtin simulator, contributed by Jim Wilson.
4817 *** Changes in GDB-4.17:
4819 * New native configurations
4821 Alpha GNU/Linux alpha*-*-linux*
4822 Unixware 2.x i[3456]86-unixware2*
4823 Irix 6.x mips*-sgi-irix6*
4824 PowerPC GNU/Linux powerpc-*-linux*
4825 PowerPC Solaris powerpcle-*-solaris*
4826 Sparc GNU/Linux sparc-*-linux*
4827 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4831 Argonaut Risc Chip (ARC) arc-*-*
4832 Hitachi H8/300S h8300*-*-*
4833 Matsushita MN10200 w/simulator mn10200-*-*
4834 Matsushita MN10300 w/simulator mn10300-*-*
4835 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4836 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4837 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4838 Mitsubishi D10V w/simulator d10v-*-*
4839 Mitsubishi M32R/D w/simulator m32r-*-elf*
4840 Tsqware Sparclet sparclet-*-*
4841 NEC V850 w/simulator v850-*-*
4843 * New debugging protocols
4845 ARM with RDI protocol arm*-*-*
4846 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4847 DDB and LSI variants of PMON protocol mips*-*-*
4848 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4849 PowerPC with SDS protocol powerpc{,le}-*-eabi
4850 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4854 All configurations can now understand and use the DWARF 2 debugging
4855 format. The choice is automatic, if the symbol file contains DWARF 2
4860 GDB now includes basic Java language support. This support is
4861 only useful with Java compilers that produce native machine code.
4863 * solib-absolute-prefix and solib-search-path
4865 For SunOS and SVR4 shared libraries, you may now set the prefix for
4866 loading absolute shared library symbol files, and the search path for
4867 locating non-absolute shared library symbol files.
4869 * Live range splitting
4871 GDB can now effectively debug code for which GCC has performed live
4872 range splitting as part of its optimization. See gdb/doc/LRS for
4873 more details on the expected format of the stabs information.
4877 GDB's support for the GNU Hurd, including thread debugging, has been
4878 updated to work with current versions of the Hurd.
4882 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4883 instruction set. ARM GDB automatically detects when Thumb
4884 instructions are in use, and adjusts disassembly and backtracing
4889 GDB's MIPS target configurations now handle the MIP16 16-bit
4894 GDB now includes support for overlays; if an executable has been
4895 linked such that multiple sections are based at the same address, GDB
4896 will decide which section to use for symbolic info. You can choose to
4897 control the decision manually, using overlay commands, or implement
4898 additional target-side support and use "overlay load-target" to bring
4899 in the overlay mapping. Do "help overlay" for more detail.
4903 The command "info symbol <address>" displays information about
4904 the symbol at the specified address.
4908 The standard remote protocol now includes an extension that allows
4909 asynchronous collection and display of trace data. This requires
4910 extensive support in the target-side debugging stub. Tracing mode
4911 includes a new interaction mode in GDB and new commands: see the
4912 file tracepoint.c for more details.
4916 Configurations for embedded MIPS now include a simulator contributed
4917 by Cygnus Solutions. The simulator supports the instruction sets
4918 of most MIPS variants.
4922 Sparc configurations may now include the ERC32 simulator contributed
4923 by the European Space Agency. The simulator is not built into
4924 Sparc targets by default; configure with --enable-sim to include it.
4928 For target configurations that may include multiple variants of a
4929 basic architecture (such as MIPS and SH), you may now set the
4930 architecture explicitly. "set arch" sets, "info arch" lists
4931 the possible architectures.
4933 *** Changes in GDB-4.16:
4935 * New native configurations
4937 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4938 M68K NetBSD m68k-*-netbsd*
4939 PowerPC AIX 4.x powerpc-*-aix*
4940 PowerPC MacOS powerpc-*-macos*
4941 PowerPC Windows NT powerpcle-*-cygwin32
4942 RS/6000 AIX 4.x rs6000-*-aix4*
4946 ARM with RDP protocol arm-*-*
4947 I960 with MON960 i960-*-coff
4948 MIPS VxWorks mips*-*-vxworks*
4949 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4950 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4952 Matra Sparclet sparclet-*-*
4956 The powerpc-eabi configuration now includes the PSIM simulator,
4957 contributed by Andrew Cagney, with assistance from Mike Meissner.
4958 PSIM is a very elaborate model of the PowerPC, including not only
4959 basic instruction set execution, but also details of execution unit
4960 performance and I/O hardware. See sim/ppc/README for more details.
4964 GDB now works with Solaris 2.5.
4966 * Windows 95/NT native
4968 GDB will now work as a native debugger on Windows 95 and Windows NT.
4969 To build it from source, you must use the "gnu-win32" environment,
4970 which uses a DLL to emulate enough of Unix to run the GNU tools.
4971 Further information, binaries, and sources are available at
4972 ftp.cygnus.com, under pub/gnu-win32.
4974 * dont-repeat command
4976 If a user-defined command includes the command `dont-repeat', then the
4977 command will not be repeated if the user just types return. This is
4978 useful if the command is time-consuming to run, so that accidental
4979 extra keystrokes don't run the same command many times.
4981 * Send break instead of ^C
4983 The standard remote protocol now includes an option to send a break
4984 rather than a ^C to the target in order to interrupt it. By default,
4985 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4987 * Remote protocol timeout
4989 The standard remote protocol includes a new variable `remotetimeout'
4990 that allows you to set the number of seconds before GDB gives up trying
4991 to read from the target. The default value is 2.
4993 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4995 By default GDB will automatically keep track of objects as they are
4996 loaded and unloaded by the dynamic linker. By using the command `set
4997 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4998 when shared library events occur, thus allowing you to set breakpoints
4999 in shared libraries which are explicitly loaded by the inferior.
5001 Note this feature does not work on hpux8. On hpux9 you must link
5002 /usr/lib/end.o into your program. This feature should work
5003 automatically on hpux10.
5005 * Irix 5.x hardware watchpoint support
5007 Irix 5 configurations now support the use of hardware watchpoints.
5009 * Mips protocol "SYN garbage limit"
5011 When debugging a Mips target using the `target mips' protocol, you
5012 may set the number of characters that GDB will ignore by setting
5013 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5014 every character. The default value is 1050.
5016 * Recording and replaying remote debug sessions
5018 If you set `remotelogfile' to the name of a file, gdb will write to it
5019 a recording of a remote debug session. This recording may then be
5020 replayed back to gdb using "gdbreplay". See gdbserver/README for
5021 details. This is useful when you have a problem with GDB while doing
5022 remote debugging; you can make a recording of the session and send it
5023 to someone else, who can then recreate the problem.
5025 * Speedups for remote debugging
5027 GDB includes speedups for downloading and stepping MIPS systems using
5028 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5029 and more efficient S-record downloading.
5031 * Memory use reductions and statistics collection
5033 GDB now uses less memory and reports statistics about memory usage.
5034 Try the `maint print statistics' command, for example.
5036 *** Changes in GDB-4.15:
5038 * Psymtabs for XCOFF
5040 The symbol reader for AIX GDB now uses partial symbol tables. This
5041 can greatly improve startup time, especially for large executables.
5043 * Remote targets use caching
5045 Remote targets now use a data cache to speed up communication with the
5046 remote side. The data cache could lead to incorrect results because
5047 it doesn't know about volatile variables, thus making it impossible to
5048 debug targets which use memory mapped I/O devices. `set remotecache
5049 off' turns the the data cache off.
5051 * Remote targets may have threads
5053 The standard remote protocol now includes support for multiple threads
5054 in the target system, using new protocol commands 'H' and 'T'. See
5055 gdb/remote.c for details.
5059 If GDB is configured with `--enable-netrom', then it will include
5060 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5061 acts as though it is a bank of ROM on the target board, but you can
5062 write into it over the network. GDB's support consists only of
5063 support for fast loading into the emulated ROM; to debug, you must use
5064 another protocol, such as standard remote protocol. The usual
5065 sequence is something like
5067 target nrom <netrom-hostname>
5069 target remote <netrom-hostname>:1235
5073 GDB now includes support for the Apple Macintosh, as a host only. It
5074 may be run as either an MPW tool or as a standalone application, and
5075 it can debug through the serial port. All the usual GDB commands are
5076 available, but to the target command, you must supply "serial" as the
5077 device type instead of "/dev/ttyXX". See mpw-README in the main
5078 directory for more information on how to build. The MPW configuration
5079 scripts */mpw-config.in support only a few targets, and only the
5080 mips-idt-ecoff target has been tested.
5084 GDB configuration now uses autoconf. This is not user-visible,
5085 but does simplify configuration and building.
5089 GDB now supports hpux10.
5091 *** Changes in GDB-4.14:
5093 * New native configurations
5095 x86 FreeBSD i[345]86-*-freebsd
5096 x86 NetBSD i[345]86-*-netbsd
5097 NS32k NetBSD ns32k-*-netbsd
5098 Sparc NetBSD sparc-*-netbsd
5102 A29K VxWorks a29k-*-vxworks
5103 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5104 CPU32 EST-300 emulator m68*-*-est*
5105 PowerPC ELF powerpc-*-elf
5108 * Alpha OSF/1 support for procfs
5110 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5111 possible to attach to running processes. As the mounting of the /proc
5112 filesystem is optional on the Alpha, GDB automatically determines
5113 the availability of /proc during startup. This can lead to problems
5114 if /proc is unmounted after GDB has been started.
5116 * Arguments to user-defined commands
5118 User commands may accept up to 10 arguments separated by whitespace.
5119 Arguments are accessed within the user command via $arg0..$arg9. A
5122 print $arg0 + $arg1 + $arg2
5124 To execute the command use:
5127 Defines the command "adder" which prints the sum of its three arguments.
5128 Note the arguments are text substitutions, so they may reference variables,
5129 use complex expressions, or even perform inferior function calls.
5131 * New `if' and `while' commands
5133 This makes it possible to write more sophisticated user-defined
5134 commands. Both commands take a single argument, which is the
5135 expression to evaluate, and must be followed by the commands to
5136 execute, one per line, if the expression is nonzero, the list being
5137 terminated by the word `end'. The `if' command list may include an
5138 `else' word, which causes the following commands to be executed only
5139 if the expression is zero.
5141 * Fortran source language mode
5143 GDB now includes partial support for Fortran 77. It will recognize
5144 Fortran programs and can evaluate a subset of Fortran expressions, but
5145 variables and functions may not be handled correctly. GDB will work
5146 with G77, but does not yet know much about symbols emitted by other
5149 * Better HPUX support
5151 Most debugging facilities now work on dynamic executables for HPPAs
5152 running hpux9 or later. You can attach to running dynamically linked
5153 processes, but by default the dynamic libraries will be read-only, so
5154 for instance you won't be able to put breakpoints in them. To change
5155 that behavior do the following before running the program:
5161 This will cause the libraries to be mapped private and read-write.
5162 To revert to the normal behavior, do this:
5168 You cannot set breakpoints or examine data in the library until after
5169 the library is loaded if the function/data symbols do not have
5172 GDB can now also read debug symbols produced by the HP C compiler on
5173 HPPAs (sorry, no C++, Fortran or 68k support).
5175 * Target byte order now dynamically selectable
5177 You can choose which byte order to use with a target system, via the
5178 commands "set endian big" and "set endian little", and you can see the
5179 current setting by using "show endian". You can also give the command
5180 "set endian auto", in which case GDB will use the byte order
5181 associated with the executable. Currently, only embedded MIPS
5182 configurations support dynamic selection of target byte order.
5184 * New DOS host serial code
5186 This version uses DPMI interrupts to handle buffered I/O, so you
5187 no longer need to run asynctsr when debugging boards connected to
5190 *** Changes in GDB-4.13:
5192 * New "complete" command
5194 This lists all the possible completions for the rest of the line, if it
5195 were to be given as a command itself. This is intended for use by emacs.
5197 * Trailing space optional in prompt
5199 "set prompt" no longer adds a space for you after the prompt you set. This
5200 allows you to set a prompt which ends in a space or one that does not.
5202 * Breakpoint hit counts
5204 "info break" now displays a count of the number of times the breakpoint
5205 has been hit. This is especially useful in conjunction with "ignore"; you
5206 can ignore a large number of breakpoint hits, look at the breakpoint info
5207 to see how many times the breakpoint was hit, then run again, ignoring one
5208 less than that number, and this will get you quickly to the last hit of
5211 * Ability to stop printing at NULL character
5213 "set print null-stop" will cause GDB to stop printing the characters of
5214 an array when the first NULL is encountered. This is useful when large
5215 arrays actually contain only short strings.
5217 * Shared library breakpoints
5219 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5220 breakpoints in shared libraries before the executable is run.
5222 * Hardware watchpoints
5224 There is a new hardware breakpoint for the watch command for sparclite
5225 targets. See gdb/sparclite/hw_breakpoint.note.
5227 Hardware watchpoints are also now supported under GNU/Linux.
5231 Annotations have been added. These are for use with graphical interfaces,
5232 and are still experimental. Currently only gdba.el uses these.
5234 * Improved Irix 5 support
5236 GDB now works properly with Irix 5.2.
5238 * Improved HPPA support
5240 GDB now works properly with the latest GCC and GAS.
5242 * New native configurations
5244 Sequent PTX4 i[34]86-sequent-ptx4
5245 HPPA running OSF/1 hppa*-*-osf*
5246 Atari TT running SVR4 m68*-*-sysv4*
5247 RS/6000 LynxOS rs6000-*-lynxos*
5251 OS/9000 i[34]86-*-os9k
5252 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5255 * Hitachi SH7000 and E7000-PC ICE support
5257 There is now support for communicating with the Hitachi E7000-PC ICE.
5258 This is available automatically when GDB is configured for the SH.
5262 As usual, a variety of small fixes and improvements, both generic
5263 and configuration-specific. See the ChangeLog for more detail.
5265 *** Changes in GDB-4.12:
5267 * Irix 5 is now supported
5271 GDB-4.12 on the HPPA has a number of changes which make it unable
5272 to debug the output from the currently released versions of GCC and
5273 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5274 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5275 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5278 *** Changes in GDB-4.11:
5280 * User visible changes:
5284 The "set remotedebug" option is now consistent between the mips remote
5285 target, remote targets using the gdb-specific protocol, UDI (AMD's
5286 debug protocol for the 29k) and the 88k bug monitor. It is now an
5287 integer specifying a debug level (normally 0 or 1, but 2 means more
5288 debugging info for the mips target).
5290 * DEC Alpha native support
5292 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5293 debug info, but GDB works fairly well with the DEC compiler and should
5294 work with a future GCC release. See the README file for a few
5295 Alpha-specific notes.
5297 * Preliminary thread implementation
5299 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5301 * LynxOS native and target support for 386
5303 This release has been hosted on LynxOS 2.2, and also can be configured
5304 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5307 * Improvements in C++ mangling/demangling.
5309 This release has much better g++ debugging, specifically in name
5310 mangling/demangling, virtual function calls, print virtual table,
5311 call methods, ...etc.
5313 *** Changes in GDB-4.10:
5315 * User visible changes:
5317 Remote debugging using the GDB-specific (`target remote') protocol now
5318 supports the `load' command. This is only useful if you have some
5319 other way of getting the stub to the target system, and you can put it
5320 somewhere in memory where it won't get clobbered by the download.
5322 Filename completion now works.
5324 When run under emacs mode, the "info line" command now causes the
5325 arrow to point to the line specified. Also, "info line" prints
5326 addresses in symbolic form (as well as hex).
5328 All vxworks based targets now support a user settable option, called
5329 vxworks-timeout. This option represents the number of seconds gdb
5330 should wait for responses to rpc's. You might want to use this if
5331 your vxworks target is, perhaps, a slow software simulator or happens
5332 to be on the far side of a thin network line.
5336 This release contains support for using a DEC alpha as a GDB host for
5337 cross debugging. Native alpha debugging is not supported yet.
5340 *** Changes in GDB-4.9:
5344 This is the first GDB release which is accompanied by a matching testsuite.
5345 The testsuite requires installation of dejagnu, which should be available
5346 via ftp from most sites that carry GNU software.
5350 'Cfront' style demangling has had its name changed to 'ARM' style, to
5351 emphasize that it was written from the specifications in the C++ Annotated
5352 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5353 disclaimers, it still generated too much confusion with users attempting to
5354 use gdb with AT&T cfront.
5358 GDB now uses a standard remote interface to a simulator library.
5359 So far, the library contains simulators for the Zilog Z8001/2, the
5360 Hitachi H8/300, H8/500 and Super-H.
5362 * New targets supported
5364 H8/300 simulator h8300-hitachi-hms or h8300hms
5365 H8/500 simulator h8500-hitachi-hms or h8500hms
5366 SH simulator sh-hitachi-hms or sh
5367 Z8000 simulator z8k-zilog-none or z8ksim
5368 IDT MIPS board over serial line mips-idt-ecoff
5370 Cross-debugging to GO32 targets is supported. It requires a custom
5371 version of the i386-stub.c module which is integrated with the
5372 GO32 memory extender.
5374 * New remote protocols
5376 MIPS remote debugging protocol.
5378 * New source languages supported
5380 This version includes preliminary support for Chill, a Pascal like language
5381 used by telecommunications companies. Chill support is also being integrated
5382 into the GNU compiler, but we don't know when it will be publically available.
5385 *** Changes in GDB-4.8:
5387 * HP Precision Architecture supported
5389 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5390 version of this support was available as a set of patches from the
5391 University of Utah. GDB does not support debugging of programs
5392 compiled with the HP compiler, because HP will not document their file
5393 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5394 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5396 Many problems in the preliminary version have been fixed.
5398 * Faster and better demangling
5400 We have improved template demangling and fixed numerous bugs in the GNU style
5401 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5402 character types (wchar_t) are now supported. Demangling of each symbol is now
5403 only done once, and is cached when the symbol table for a file is read in.
5404 This results in a small increase in memory usage for C programs, a moderate
5405 increase in memory usage for C++ programs, and a fantastic speedup in
5408 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5409 from the specifications in the Annotated Reference Manual, which AT&T's
5410 compiler does not actually implement.
5412 * G++ multiple inheritance compiler problem
5414 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5415 inheritance lattices was reworked to properly discover ambiguities. We
5416 recently found an example which causes this new algorithm to fail in a
5417 very subtle way, producing bad debug information for those classes.
5418 The file 'gcc.patch' (in this directory) can be applied to gcc to
5419 circumvent the problem. A future GCC release will contain a complete
5422 The previous G++ debug info problem (mentioned below for the gdb-4.7
5423 release) is fixed in gcc version 2.3.2.
5425 * Improved configure script
5427 The `configure' script will now attempt to guess your system type if
5428 you don't supply a host system type. The old scheme of supplying a
5429 host system triplet is preferable over using this. All the magic is
5430 done in the new `config.guess' script. Examine it for details.
5432 We have also brought our configure script much more in line with the FSF's
5433 version. It now supports the --with-xxx options. In particular,
5434 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5435 The resulting GDB will not be able to read arbitrary object file formats --
5436 only the format ``expected'' to be used on the configured target system.
5437 We hope to make this the default in a future release.
5439 * Documentation improvements
5441 There's new internal documentation on how to modify GDB, and how to
5442 produce clean changes to the code. We implore people to read it
5443 before submitting changes.
5445 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5446 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5447 `info' files are also provided. To build `info' files from scratch,
5448 you will need the latest `makeinfo' release, which will be available in
5449 a future texinfo-X.Y release.
5451 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5452 We're not sure exactly which versions have this problem, but it has
5453 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5454 or better. If that isn't possible, there is a patch in
5455 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5456 around this problem.
5460 GDB now supports array constants that can be used in expressions typed in by
5461 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5462 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5465 The new directory `gdb/sparclite' contains a program that demonstrates
5466 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5468 * New native hosts supported
5470 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5471 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5473 * New targets supported
5475 AMD 29k family via UDI a29k-amd-udi or udi29k
5477 * New file formats supported
5479 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5480 HPUX core files, and SCO 3.2v2 core files.
5484 Attaching to processes now works again; thanks for the many bug reports.
5486 We have also stomped on a bunch of core dumps caused by
5487 printf_filtered("%s") problems.
5489 We eliminated a copyright problem on the rpc and ptrace header files
5490 for VxWorks, which was discovered at the last minute during the 4.7
5491 release. You should now be able to build a VxWorks GDB.
5493 You can now interrupt gdb while an attached process is running. This
5494 will cause the attached process to stop, and give control back to GDB.
5496 We fixed problems caused by using too many file descriptors
5497 for reading symbols from object files and libraries. This was
5498 especially a problem for programs that used many (~100) shared
5501 The `step' command now only enters a subroutine if there is line number
5502 information for the subroutine. Otherwise it acts like the `next'
5503 command. Previously, `step' would enter subroutines if there was
5504 any debugging information about the routine. This avoids problems
5505 when using `cc -g1' on MIPS machines.
5507 * Internal improvements
5509 GDB's internal interfaces have been improved to make it easier to support
5510 debugging of multiple languages in the future.
5512 GDB now uses a common structure for symbol information internally.
5513 Minimal symbols (derived from linkage symbols in object files), partial
5514 symbols (from a quick scan of debug information), and full symbols
5515 contain a common subset of information, making it easier to write
5516 shared code that handles any of them.
5518 * New command line options
5520 We now accept --silent as an alias for --quiet.
5524 The memory-mapped-malloc library is now licensed under the GNU Library
5525 General Public License.
5527 *** Changes in GDB-4.7:
5529 * Host/native/target split
5531 GDB has had some major internal surgery to untangle the support for
5532 hosts and remote targets. Now, when you configure GDB for a remote
5533 target, it will no longer load in all of the support for debugging
5534 local programs on the host. When fully completed and tested, this will
5535 ensure that arbitrary host/target combinations are possible.
5537 The primary conceptual shift is to separate the non-portable code in
5538 GDB into three categories. Host specific code is required any time GDB
5539 is compiled on that host, regardless of the target. Target specific
5540 code relates to the peculiarities of the target, but can be compiled on
5541 any host. Native specific code is everything else: it can only be
5542 built when the host and target are the same system. Child process
5543 handling and core file support are two common `native' examples.
5545 GDB's use of /proc for controlling Unix child processes is now cleaner.
5546 It has been split out into a single module under the `target_ops' vector,
5547 plus two native-dependent functions for each system that uses /proc.
5549 * New hosts supported
5551 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5552 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5553 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5555 * New targets supported
5557 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5558 68030 and CPU32 m68030-*-*, m68332-*-*
5560 * New native hosts supported
5562 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5563 (386bsd is not well tested yet)
5564 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5566 * New file formats supported
5568 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5569 supports reading of `a.out.adobe' object files, which are an a.out
5570 format extended with minimal information about multiple sections.
5574 `show copying' is the same as the old `info copying'.
5575 `show warranty' is the same as `info warrantee'.
5576 These were renamed for consistency. The old commands continue to work.
5578 `info handle' is a new alias for `info signals'.
5580 You can now define pre-command hooks, which attach arbitrary command
5581 scripts to any command. The commands in the hook will be executed
5582 prior to the user's command. You can also create a hook which will be
5583 executed whenever the program stops. See gdb.texinfo.
5587 We now deal with Cfront style name mangling, and can even extract type
5588 info from mangled symbols. GDB can automatically figure out which
5589 symbol mangling style your C++ compiler uses.
5591 Calling of methods and virtual functions has been improved as well.
5595 The crash that occured when debugging Sun Ansi-C compiled binaries is
5596 fixed. This was due to mishandling of the extra N_SO stabs output
5599 We also finally got Ultrix 4.2 running in house, and fixed core file
5600 support, with help from a dozen people on the net.
5602 John M. Farrell discovered that the reason that single-stepping was so
5603 slow on all of the Mips based platforms (primarily SGI and DEC) was
5604 that we were trying to demangle and lookup a symbol used for internal
5605 purposes on every instruction that was being stepped through. Changing
5606 the name of that symbol so that it couldn't be mistaken for a C++
5607 mangled symbol sped things up a great deal.
5609 Rich Pixley sped up symbol lookups in general by getting much smarter
5610 about when C++ symbol mangling is necessary. This should make symbol
5611 completion (TAB on the command line) much faster. It's not as fast as
5612 we'd like, but it's significantly faster than gdb-4.6.
5616 A new user controllable variable 'call_scratch_address' can
5617 specify the location of a scratch area to be used when GDB
5618 calls a function in the target. This is necessary because the
5619 usual method of putting the scratch area on the stack does not work
5620 in systems that have separate instruction and data spaces.
5622 We integrated changes to support the 29k UDI (Universal Debugger
5623 Interface), but discovered at the last minute that we didn't have all
5624 of the appropriate copyright paperwork. We are working with AMD to
5625 resolve this, and hope to have it available soon.
5629 We have sped up the remote serial line protocol, especially for targets
5630 with lots of registers. It now supports a new `expedited status' ('T')
5631 message which can be used in place of the existing 'S' status message.
5632 This allows the remote stub to send only the registers that GDB
5633 needs to make a quick decision about single-stepping or conditional
5634 breakpoints, eliminating the need to fetch the entire register set for
5635 each instruction being stepped through.
5637 The GDB remote serial protocol now implements a write-through cache for
5638 registers, only re-reading the registers if the target has run.
5640 There is also a new remote serial stub for SPARC processors. You can
5641 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5642 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5643 processor with a serial port.
5647 Configure.in files have become much easier to read and modify. A new
5648 `table driven' format makes it more obvious what configurations are
5649 supported, and what files each one uses.
5653 There is a new opcodes library which will eventually contain all of the
5654 disassembly routines and opcode tables. At present, it only contains
5655 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5656 disassembler (binutils/objdump) to share these routines.
5658 The libiberty library is now copylefted under the GNU Library General
5659 Public License. This allows more liberal use, and was done so libg++
5660 can use it. This makes no difference to GDB, since the Library License
5661 grants all the rights from the General Public License.
5665 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5666 reference to the stabs symbol info used by the debugger. It is (as far
5667 as we know) the only published document on this fascinating topic. We
5668 encourage you to read it, compare it to the stabs information on your
5669 system, and send improvements on the document in general (to
5670 bug-gdb@prep.ai.mit.edu).
5672 And, of course, many bugs have been fixed.
5675 *** Changes in GDB-4.6:
5677 * Better support for C++ function names
5679 GDB now accepts as input the "demangled form" of C++ overloaded function
5680 names and member function names, and can do command completion on such names
5681 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5682 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5683 Make use of command completion, it is your friend.
5685 GDB also now accepts a variety of C++ mangled symbol formats. They are
5686 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5687 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5688 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5689 for the list of formats.
5691 * G++ symbol mangling problem
5693 Recent versions of gcc have a bug in how they emit debugging information for
5694 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5695 directory) can be applied to gcc to fix the problem. Alternatively, if you
5696 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5697 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5698 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5701 * New 'maintenance' command
5703 All of the commands related to hacking GDB internals have been moved out of
5704 the main command set, and now live behind the 'maintenance' command. This
5705 can also be abbreviated as 'mt'. The following changes were made:
5707 dump-me -> maintenance dump-me
5708 info all-breakpoints -> maintenance info breakpoints
5709 printmsyms -> maintenance print msyms
5710 printobjfiles -> maintenance print objfiles
5711 printpsyms -> maintenance print psymbols
5712 printsyms -> maintenance print symbols
5714 The following commands are new:
5716 maintenance demangle Call internal GDB demangler routine to
5717 demangle a C++ link name and prints the result.
5718 maintenance print type Print a type chain for a given symbol
5720 * Change to .gdbinit file processing
5722 We now read the $HOME/.gdbinit file before processing the argv arguments
5723 (e.g. reading symbol files or core files). This allows global parameters to
5724 be set, which will apply during the symbol reading. The ./.gdbinit is still
5725 read after argv processing.
5727 * New hosts supported
5729 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5731 GNU/Linux support i386-unknown-linux or linux
5733 We are also including code to support the HP/PA running BSD and HPUX. This
5734 is almost guaranteed not to work, as we didn't have time to test or build it
5735 for this release. We are including it so that the more adventurous (or
5736 masochistic) of you can play with it. We also had major problems with the
5737 fact that the compiler that we got from HP doesn't support the -g option.
5740 * New targets supported
5742 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5744 * More smarts about finding #include files
5746 GDB now remembers the compilation directory for all include files, and for
5747 all files from which C is generated (like yacc and lex sources). This
5748 greatly improves GDB's ability to find yacc/lex sources, and include files,
5749 especially if you are debugging your program from a directory different from
5750 the one that contains your sources.
5752 We also fixed a bug which caused difficulty with listing and setting
5753 breakpoints in include files which contain C code. (In the past, you had to
5754 try twice in order to list an include file that you hadn't looked at before.)
5756 * Interesting infernals change
5758 GDB now deals with arbitrary numbers of sections, where the symbols for each
5759 section must be relocated relative to that section's landing place in the
5760 target's address space. This work was needed to support ELF with embedded
5761 stabs used by Solaris-2.0.
5763 * Bug fixes (of course!)
5765 There have been loads of fixes for the following things:
5766 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5767 i960, stabs, DOS(GO32), procfs, etc...
5769 See the ChangeLog for details.
5771 *** Changes in GDB-4.5:
5773 * New machines supported (host and target)
5775 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5777 SGI Irix-4.x mips-sgi-irix4 or iris4
5779 * New malloc package
5781 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5782 Mmalloc is capable of handling mutiple heaps of memory. It is also
5783 capable of saving a heap to a file, and then mapping it back in later.
5784 This can be used to greatly speedup the startup of GDB by using a
5785 pre-parsed symbol table which lives in a mmalloc managed heap. For
5786 more details, please read mmalloc/mmalloc.texi.
5790 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5791 'help info proc' for details.
5793 * MIPS ecoff symbol table format
5795 The code that reads MIPS symbol table format is now supported on all hosts.
5796 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5799 * File name changes for MS-DOS
5801 Many files in the config directories have been renamed to make it easier to
5802 support GDB on MS-DOSe systems (which have very restrictive file name
5803 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5804 environment) is close to working but has some remaining problems. Note
5805 that debugging of DOS programs is not supported, due to limitations
5806 in the ``operating system'', but it can be used to host cross-debugging.
5808 * Cross byte order fixes
5810 Many fixes have been made to support cross debugging of Sparc and MIPS
5811 targets from hosts whose byte order differs.
5813 * New -mapped and -readnow options
5815 If memory-mapped files are available on your system through the 'mmap'
5816 system call, you can use the -mapped option on the `file' or
5817 `symbol-file' commands to cause GDB to write the symbols from your
5818 program into a reusable file. If the program you are debugging is
5819 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5820 Future GDB debugging sessions will notice the presence of this file,
5821 and will quickly map in symbol information from it, rather than reading
5822 the symbol table from the executable program. Using the '-mapped'
5823 option in a GDB `file' or `symbol-file' command has the same effect as
5824 starting GDB with the '-mapped' command-line option.
5826 You can cause GDB to read the entire symbol table immediately by using
5827 the '-readnow' option with any of the commands that load symbol table
5828 information (or on the GDB command line). This makes the command
5829 slower, but makes future operations faster.
5831 The -mapped and -readnow options are typically combined in order to
5832 build a `fred.syms' file that contains complete symbol information.
5833 A simple GDB invocation to do nothing but build a `.syms' file for future
5836 gdb -batch -nx -mapped -readnow programname
5838 The `.syms' file is specific to the host machine on which GDB is run.
5839 It holds an exact image of GDB's internal symbol table. It cannot be
5840 shared across multiple host platforms.
5842 * longjmp() handling
5844 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5845 siglongjmp() without losing control. This feature has not yet been ported to
5846 all systems. It currently works on many 386 platforms, all MIPS-based
5847 platforms (SGI, DECstation, etc), and Sun3/4.
5851 Preliminary work has been put in to support the new Solaris OS from Sun. At
5852 this time, it can control and debug processes, but it is not capable of
5857 As always, many many bug fixes. The major areas were with g++, and mipsread.
5858 People using the MIPS-based platforms should experience fewer mysterious
5859 crashes and trashed symbol tables.
5861 *** Changes in GDB-4.4:
5863 * New machines supported (host and target)
5865 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5867 BSD Reno on Vax vax-dec-bsd
5868 Ultrix on Vax vax-dec-ultrix
5870 * New machines supported (target)
5872 AMD 29000 embedded, using EBMON a29k-none-none
5876 GDB continues to improve its handling of C++. `References' work better.
5877 The demangler has also been improved, and now deals with symbols mangled as
5878 per the Annotated C++ Reference Guide.
5880 GDB also now handles `stabs' symbol information embedded in MIPS
5881 `ecoff' symbol tables. Since the ecoff format was not easily
5882 extensible to handle new languages such as C++, this appeared to be a
5883 good way to put C++ debugging info into MIPS binaries. This option
5884 will be supported in the GNU C compiler, version 2, when it is
5887 * New features for SVR4
5889 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5890 shared libraries. Debugging dynamically linked programs should present
5891 only minor differences from debugging statically linked programs.
5893 The `info proc' command will print out information about any process
5894 on an SVR4 system (including the one you are debugging). At the moment,
5895 it prints the address mappings of the process.
5897 If you bring up GDB on another SVR4 system, please send mail to
5898 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5900 * Better dynamic linking support in SunOS
5902 Reading symbols from shared libraries which contain debugging symbols
5903 now works properly. However, there remain issues such as automatic
5904 skipping of `transfer vector' code during function calls, which
5905 make it harder to debug code in a shared library, than to debug the
5906 same code linked statically.
5910 GDB is now using the latest `getopt' routines from the FSF. This
5911 version accepts the -- prefix for options with long names. GDB will
5912 continue to accept the old forms (-option and +option) as well.
5913 Various single letter abbreviations for options have been explicity
5914 added to the option table so that they won't get overshadowed in the
5915 future by other options that begin with the same letter.
5919 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5920 Many assorted bugs have been handled. Many more remain to be handled.
5921 See the various ChangeLog files (primarily in gdb and bfd) for details.
5924 *** Changes in GDB-4.3:
5926 * New machines supported (host and target)
5928 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5929 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5930 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5932 * Almost SCO Unix support
5934 We had hoped to support:
5935 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5936 (except for core file support), but we discovered very late in the release
5937 that it has problems with process groups that render gdb unusable. Sorry
5938 about that. I encourage people to fix it and post the fixes.
5940 * Preliminary ELF and DWARF support
5942 GDB can read ELF object files on System V Release 4, and can handle
5943 debugging records for C, in DWARF format, in ELF files. This support
5944 is preliminary. If you bring up GDB on another SVR4 system, please
5945 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5950 GDB now uses the latest `readline' library. One user-visible change
5951 is that two tabs will list possible command completions, which previously
5952 required typing M-? (meta-question mark, or ESC ?).
5956 The `stepi' bug that many of you noticed has been squashed.
5957 Many bugs in C++ have been handled. Many more remain to be handled.
5958 See the various ChangeLog files (primarily in gdb and bfd) for details.
5960 * State of the MIPS world (in case you wondered):
5962 GDB can understand the symbol tables emitted by the compilers
5963 supplied by most vendors of MIPS-based machines, including DEC. These
5964 symbol tables are in a format that essentially nobody else uses.
5966 Some versions of gcc come with an assembler post-processor called
5967 mips-tfile. This program is required if you want to do source-level
5968 debugging of gcc-compiled programs. I believe FSF does not ship
5969 mips-tfile with gcc version 1, but it will eventually come with gcc
5972 Debugging of g++ output remains a problem. g++ version 1.xx does not
5973 really support it at all. (If you're lucky, you should be able to get
5974 line numbers and stack traces to work, but no parameters or local
5975 variables.) With some work it should be possible to improve the
5978 When gcc version 2 is released, you will have somewhat better luck.
5979 However, even then you will get confusing results for inheritance and
5982 We will eventually provide full debugging of g++ output on
5983 DECstations. This will probably involve some kind of stabs-in-ecoff
5984 encapulation, but the details have not been worked out yet.
5987 *** Changes in GDB-4.2:
5989 * Improved configuration
5991 Only one copy of `configure' exists now, and it is not self-modifying.
5992 Porting BFD is simpler.
5996 The `step' and `next' commands now only stop at the first instruction
5997 of a source line. This prevents the multiple stops that used to occur
5998 in switch statements, for-loops, etc. `Step' continues to stop if a
5999 function that has debugging information is called within the line.
6003 Lots of small bugs fixed. More remain.
6005 * New host supported (not target)
6007 Intel 386 PC clone running Mach i386-none-mach
6010 *** Changes in GDB-4.1:
6012 * Multiple source language support
6014 GDB now has internal scaffolding to handle several source languages.
6015 It determines the type of each source file from its filename extension,
6016 and will switch expression parsing and number formatting to match the
6017 language of the function in the currently selected stack frame.
6018 You can also specifically set the language to be used, with
6019 `set language c' or `set language modula-2'.
6023 GDB now has preliminary support for the GNU Modula-2 compiler,
6024 currently under development at the State University of New York at
6025 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6026 continue through the fall of 1991 and into 1992.
6028 Other Modula-2 compilers are currently not supported, and attempting to
6029 debug programs compiled with them will likely result in an error as the
6030 symbol table is read. Feel free to work on it, though!
6032 There are hooks in GDB for strict type checking and range checking,
6033 in the `Modula-2 philosophy', but they do not currently work.
6037 GDB can now write to executable and core files (e.g. patch
6038 a variable's value). You must turn this switch on, specify
6039 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6040 by assigning a new value to a variable. Modifications take
6043 * Automatic SunOS shared library reading
6045 When you run your program, GDB automatically determines where its
6046 shared libraries (if any) have been loaded, and reads their symbols.
6047 The `share' command is no longer needed. This also works when
6048 examining core files.
6052 You can specify the number of lines that the `list' command shows.
6055 * New machines supported (host and target)
6057 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6058 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6059 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6061 * New hosts supported (not targets)
6063 IBM RT/PC: romp-ibm-aix or rtpc
6065 * New targets supported (not hosts)
6067 AMD 29000 embedded with COFF a29k-none-coff
6068 AMD 29000 embedded with a.out a29k-none-aout
6069 Ultracomputer remote kernel debug a29k-nyu-kern
6071 * New remote interfaces
6077 *** Changes in GDB-4.0:
6081 Wide output is wrapped at good places to make the output more readable.
6083 Gdb now supports cross-debugging from a host machine of one type to a
6084 target machine of another type. Communication with the target system
6085 is over serial lines. The ``target'' command handles connecting to the
6086 remote system; the ``load'' command will download a program into the
6087 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6088 also supports debugging of realtime processes running under VxWorks,
6089 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6090 stub on the target system.
6092 New CPUs supported include the AMD 29000 and Intel 960.
6094 GDB now reads object files and symbol tables via a ``binary file''
6095 library, which allows a single copy of GDB to debug programs of multiple
6096 object file types such as a.out and coff.
6098 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6099 refcard.dvi and refcard.ps are available to format it).
6102 * Control-Variable user interface simplified
6104 All variables that control the operation of the debugger can be set
6105 by the ``set'' command, and displayed by the ``show'' command.
6107 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6108 ``Show prompt'' produces the response:
6109 Gdb's prompt is new-gdb=>.
6111 What follows are the NEW set commands. The command ``help set'' will
6112 print a complete list of old and new set commands. ``help set FOO''
6113 will give a longer description of the variable FOO. ``show'' will show
6114 all of the variable descriptions and their current settings.
6116 confirm on/off: Enables warning questions for operations that are
6117 hard to recover from, e.g. rerunning the program while
6118 it is already running. Default is ON.
6120 editing on/off: Enables EMACS style command line editing
6121 of input. Previous lines can be recalled with
6122 control-P, the current line can be edited with control-B,
6123 you can search for commands with control-R, etc.
6126 history filename NAME: NAME is where the gdb command history
6127 will be stored. The default is .gdb_history,
6128 or the value of the environment variable
6131 history size N: The size, in commands, of the command history. The
6132 default is 256, or the value of the environment variable
6135 history save on/off: If this value is set to ON, the history file will
6136 be saved after exiting gdb. If set to OFF, the
6137 file will not be saved. The default is OFF.
6139 history expansion on/off: If this value is set to ON, then csh-like
6140 history expansion will be performed on
6141 command line input. The default is OFF.
6143 radix N: Sets the default radix for input and output. It can be set
6144 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6145 in the current radix, so "set radix 10" is always a no-op.
6147 height N: This integer value is the number of lines on a page. Default
6148 is 24, the current `stty rows'' setting, or the ``li#''
6149 setting from the termcap entry matching the environment
6152 width N: This integer value is the number of characters on a line.
6153 Default is 80, the current `stty cols'' setting, or the ``co#''
6154 setting from the termcap entry matching the environment
6157 Note: ``set screensize'' is obsolete. Use ``set height'' and
6158 ``set width'' instead.
6160 print address on/off: Print memory addresses in various command displays,
6161 such as stack traces and structure values. Gdb looks
6162 more ``symbolic'' if you turn this off; it looks more
6163 ``machine level'' with it on. Default is ON.
6165 print array on/off: Prettyprint arrays. New convenient format! Default
6168 print demangle on/off: Print C++ symbols in "source" form if on,
6171 print asm-demangle on/off: Same, for assembler level printouts
6174 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6177 * Support for Epoch Environment.
6179 The epoch environment is a version of Emacs v18 with windowing. One
6180 new command, ``inspect'', is identical to ``print'', except that if you
6181 are running in the epoch environment, the value is printed in its own
6185 * Support for Shared Libraries
6187 GDB can now debug programs and core files that use SunOS shared libraries.
6188 Symbols from a shared library cannot be referenced
6189 before the shared library has been linked with the program (this
6190 happens after you type ``run'' and before the function main() is entered).
6191 At any time after this linking (including when examining core files
6192 from dynamically linked programs), gdb reads the symbols from each
6193 shared library when you type the ``sharedlibrary'' command.
6194 It can be abbreviated ``share''.
6196 sharedlibrary REGEXP: Load shared object library symbols for files
6197 matching a unix regular expression. No argument
6198 indicates to load symbols for all shared libraries.
6200 info sharedlibrary: Status of loaded shared libraries.
6205 A watchpoint stops execution of a program whenever the value of an
6206 expression changes. Checking for this slows down execution
6207 tremendously whenever you are in the scope of the expression, but is
6208 quite useful for catching tough ``bit-spreader'' or pointer misuse
6209 problems. Some machines such as the 386 have hardware for doing this
6210 more quickly, and future versions of gdb will use this hardware.
6212 watch EXP: Set a watchpoint (breakpoint) for an expression.
6214 info watchpoints: Information about your watchpoints.
6216 delete N: Deletes watchpoint number N (same as breakpoints).
6217 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6218 enable N: Re-enables watchpoint number N (same as breakpoints).
6221 * C++ multiple inheritance
6223 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6226 * C++ exception handling
6228 Gdb now supports limited C++ exception handling. Besides the existing
6229 ability to breakpoint on an exception handler, gdb can breakpoint on
6230 the raising of an exception (before the stack is peeled back to the
6233 catch FOO: If there is a FOO exception handler in the dynamic scope,
6234 set a breakpoint to catch exceptions which may be raised there.
6235 Multiple exceptions (``catch foo bar baz'') may be caught.
6237 info catch: Lists all exceptions which may be caught in the
6238 current stack frame.
6241 * Minor command changes
6243 The command ``call func (arg, arg, ...)'' now acts like the print
6244 command, except it does not print or save a value if the function's result
6245 is void. This is similar to dbx usage.
6247 The ``up'' and ``down'' commands now always print the frame they end up
6248 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6249 frames without printing.
6251 * New directory command
6253 'dir' now adds directories to the FRONT of the source search path.
6254 The path starts off empty. Source files that contain debug information
6255 about the directory in which they were compiled can be found even
6256 with an empty path; Sun CC and GCC include this information. If GDB can't
6257 find your source file in the current directory, type "dir .".
6259 * Configuring GDB for compilation
6261 For normal use, type ``./configure host''. See README or gdb.texinfo
6264 GDB now handles cross debugging. If you are remotely debugging between
6265 two different machines, type ``./configure host -target=targ''.
6266 Host is the machine where GDB will run; targ is the machine
6267 where the program that you are debugging will run.