1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.10
6 * Record btrace now supports non-stop mode.
8 * Support for tracepoints on aarch64-linux was added in GDBserver.
10 * The 'record instruction-history' command now indicates speculative execution
11 when using the Intel(R) Processor Trace recording format.
13 * GDB now allows users to specify explicit locations, bypassing
14 the linespec parser. This feature is also available to GDB/MI
17 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
18 GDB now is able to debug both AArch64 applications and ARM applications
21 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
22 including JIT compiling fast tracepoint's conditional expression bytecode
25 * GDB now supports displaced stepping on AArch64 GNU/Linux.
27 * "info threads", "info inferiors", "info display", "info checkpoints"
28 and "maint info program-spaces" now list the corresponding items in
29 ascending ID order, for consistency with all other "info" commands.
31 * In Ada, the overloads selection menu has been enhanced to display the
32 parameter types and the return types for the matching overloaded subprograms.
36 maint set target-non-stop (on|off|auto)
37 maint show target-non-stop
38 Control whether GDB targets always operate in non-stop mode even if
39 "set non-stop" is "off". The default is "auto", meaning non-stop
40 mode is enabled if supported by the target.
43 maint show bfd-sharing
44 Control the reuse of bfd objects.
48 Control display of debugging info regarding bfd caching.
50 set remote multiprocess-extensions-packet
51 show remote multiprocess-extensions-packet
52 Set/show the use of the remote protocol multiprocess extensions.
54 set remote thread-events
55 show remote thread-events
56 Set/show the use of thread create/exit events.
58 set ada print-signatures on|off
59 show ada print-signatures"
60 Control whether parameter types and return types are displayed in overloads
61 selection menus. It is activaled (@code{on}) by default.
63 * The "disassemble" command accepts a new modifier: /s.
64 It prints mixed source+disassembly like /m with two differences:
65 - disassembled instructions are now printed in program order, and
66 - and source for all relevant files is now printed.
67 The "/m" option is now considered deprecated: its "source-centric"
68 output hasn't proved useful in practice.
70 * The "record instruction-history" command accepts a new modifier: /s.
71 It behaves exactly like /m and prints mixed source+disassembly.
73 * The "set scheduler-locking" command supports a new mode "replay".
74 It behaves like "off" in record mode and like "on" in replay mode.
76 * Support for various ROM monitors has been removed:
78 target dbug dBUG ROM monitor for Motorola ColdFire
79 target picobug Motorola picobug monitor
80 target dink32 DINK32 ROM monitor for PowerPC
81 target m32r Renesas M32R/D ROM monitor
82 target mon2000 mon2000 ROM monitor
83 target ppcbug PPCBUG ROM monitor for PowerPC
85 * Support for reading/writing memory and extracting values on architectures
86 whose memory is addressable in units of any integral multiple of 8 bits.
91 Indicates that an exec system call was executed.
93 exec-events feature in qSupported
94 The qSupported packet allows GDB to request support for exec
95 events using the new 'gdbfeature' exec-event, and the qSupported
96 response can contain the corresponding 'stubfeature'. Set and
97 show commands can be used to display whether these features are enabled.
100 Equivalent to interrupting with the ^C character, but works in
103 thread created stop reason (T05 create:...)
104 Indicates that the thread was just created and is stopped at entry.
106 thread exit stop reply (w exitcode;tid)
107 Indicates that the thread has terminated.
110 Enables/disables thread create and exit event reporting. For
111 example, this is used in non-stop mode when GDB stops a set of
112 threads and synchronously waits for the their corresponding stop
113 replies. Without exit events, if one of the threads exits, GDB
114 would hang forever not knowing that it should no longer expect a
115 stop for that same thread.
119 Indicates that there are no resumed threads left in the target (all
120 threads are stopped). The remote stub reports support for this stop
121 reply to GDB's qSupported query.
123 * Extended-remote exec events
125 ** GDB now has support for exec events on extended-remote Linux targets.
126 For such targets with Linux kernels 2.5.46 and later, this enables
127 follow-exec-mode and exec catchpoints.
129 set remote exec-event-feature-packet
130 show remote exec-event-feature-packet
131 Set/show the use of the remote exec event feature.
133 * Thread names in remote protocol
135 The reply to qXfer:threads:read may now include a name attribute for each
140 ** The -var-set-format command now accepts the zero-hexadecimal
141 format. It outputs data in hexadecimal format with zero-padding on the
144 *** Changes in GDB 7.10
146 * Support for process record-replay and reverse debugging on aarch64*-linux*
147 targets has been added. GDB now supports recording of A64 instruction set
148 including advance SIMD instructions.
150 * Support for Sun's version of the "stabs" debug file format has been removed.
152 * GDB now honors the content of the file /proc/PID/coredump_filter
153 (PID is the process ID) on GNU/Linux systems. This file can be used
154 to specify the types of memory mappings that will be included in a
155 corefile. For more information, please refer to the manual page of
156 "core(5)". GDB also has a new command: "set use-coredump-filter
157 on|off". It allows to set whether GDB will read the content of the
158 /proc/PID/coredump_filter file when generating a corefile.
160 * The "info os" command on GNU/Linux can now display information on
162 "info os cpus" Listing of all cpus/cores on the system
164 * GDB has two new commands: "set serial parity odd|even|none" and
165 "show serial parity". These allows to set or show parity for the
168 * The "info source" command now displays the producer string if it was
169 present in the debug info. This typically includes the compiler version
170 and may include things like its command line arguments.
172 * The "info dll", an alias of the "info sharedlibrary" command,
173 is now available on all platforms.
175 * Directory names supplied to the "set sysroot" commands may be
176 prefixed with "target:" to tell GDB to access shared libraries from
177 the target system, be it local or remote. This replaces the prefix
178 "remote:". The default sysroot has been changed from "" to
179 "target:". "remote:" is automatically converted to "target:" for
180 backward compatibility.
182 * The system root specified by "set sysroot" will be prepended to the
183 filename of the main executable (if reported to GDB as absolute by
184 the operating system) when starting processes remotely, and when
185 attaching to already-running local or remote processes.
187 * GDB now supports automatic location and retrieval of executable
188 files from remote targets. Remote debugging can now be initiated
189 using only a "target remote" or "target extended-remote" command
190 (no "set sysroot" or "file" commands are required). See "New remote
193 * The "dump" command now supports verilog hex format.
195 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
197 * On GNU/Linux, GDB and gdbserver are now able to access executable
198 and shared library files without a "set sysroot" command when
199 attaching to processes running in different mount namespaces from
200 the debugger. This makes it possible to attach to processes in
201 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
202 See "New remote packets" below.
204 * The "tui reg" command now provides completion for all of the
205 available register groups, including target specific groups.
207 * The HISTSIZE environment variable is no longer read when determining
208 the size of GDB's command history. GDB now instead reads the dedicated
209 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
210 disables truncation of command history. Non-numeric values of GDBHISTSIZE
215 ** Memory ports can now be unbuffered.
219 ** gdb.Objfile objects have a new attribute "username",
220 which is the name of the objfile as specified by the user,
221 without, for example, resolving symlinks.
222 ** You can now write frame unwinders in Python.
223 ** gdb.Type objects have a new method "optimized_out",
224 returning optimized out gdb.Value instance of this type.
225 ** gdb.Value objects have new methods "reference_value" and
226 "const_value" which return a reference to the value and a
227 "const" version of the value respectively.
231 maint print symbol-cache
232 Print the contents of the symbol cache.
234 maint print symbol-cache-statistics
235 Print statistics of symbol cache usage.
237 maint flush-symbol-cache
238 Flush the contents of the symbol cache.
242 Start branch trace recording using Branch Trace Store (BTS) format.
245 Evaluate expression by using the compiler and print result.
249 Explicit commands for enabling and disabling tui mode.
252 set mpx bound on i386 and amd64
253 Support for bound table investigation on Intel(R) MPX enabled applications.
257 Start branch trace recording using Intel(R) Processor Trace format.
260 Print information about branch tracing internals.
262 maint btrace packet-history
263 Print the raw branch tracing data.
265 maint btrace clear-packet-history
266 Discard the stored raw branch tracing data.
269 Discard all branch tracing data. It will be fetched and processed
270 anew by the next "record" command.
275 Renamed from "set debug dwarf2-die".
277 Renamed from "show debug dwarf2-die".
280 Renamed from "set debug dwarf2-read".
281 show debug dwarf-read
282 Renamed from "show debug dwarf2-read".
284 maint set dwarf always-disassemble
285 Renamed from "maint set dwarf2 always-disassemble".
286 maint show dwarf always-disassemble
287 Renamed from "maint show dwarf2 always-disassemble".
289 maint set dwarf max-cache-age
290 Renamed from "maint set dwarf2 max-cache-age".
291 maint show dwarf max-cache-age
292 Renamed from "maint show dwarf2 max-cache-age".
295 show debug dwarf-line
296 Control display of debugging info regarding DWARF line processing.
300 Set the maximum number of candidates to be considered during
301 completion. The default value is 200. This limit allows GDB
302 to avoid generating large completion lists, the computation of
303 which can cause the debugger to become temporarily unresponsive.
305 set history remove-duplicates
306 show history remove-duplicates
307 Control the removal of duplicate history entries.
309 maint set symbol-cache-size
310 maint show symbol-cache-size
311 Control the size of the symbol cache.
313 set|show record btrace bts buffer-size
314 Set and show the size of the ring buffer used for branch tracing in
316 The obtained size may differ from the requested size. Use "info
317 record" to see the obtained buffer size.
319 set debug linux-namespaces
320 show debug linux-namespaces
321 Control display of debugging info regarding Linux namespaces.
323 set|show record btrace pt buffer-size
324 Set and show the size of the ring buffer used for branch tracing in
325 Intel(R) Processor Trace format.
326 The obtained size may differ from the requested size. Use "info
327 record" to see the obtained buffer size.
329 maint set|show btrace pt skip-pad
330 Set and show whether PAD packets are skipped when computing the
333 * The command 'thread apply all' can now support new option '-ascending'
334 to call its specified command for all threads in ascending order.
336 * Python/Guile scripting
338 ** GDB now supports auto-loading of Python/Guile scripts contained in the
339 special section named `.debug_gdb_scripts'.
343 qXfer:btrace-conf:read
344 Return the branch trace configuration for the current thread.
346 Qbtrace-conf:bts:size
347 Set the requested ring buffer size for branch tracing in BTS format.
350 Enable Intel(R) Procesor Trace-based branch tracing for the current
351 process. The remote stub reports support for this packet to GDB's
355 Set the requested ring buffer size for branch tracing in Intel(R) Processor
359 Indicates a memory breakpoint instruction was executed, irrespective
360 of whether it was GDB that planted the breakpoint or the breakpoint
361 is hardcoded in the program. This is required for correct non-stop
365 Indicates the target stopped for a hardware breakpoint. This is
366 required for correct non-stop mode operation.
369 Return information about files on the remote system.
372 Return the full absolute name of the file that was executed to
373 create a process running on the remote system.
376 Select the filesystem on which vFile: operations with filename
377 arguments will operate. This is required for GDB to be able to
378 access files on remote targets where the remote stub does not
379 share a common filesystem with the inferior(s).
382 Indicates that a fork system call was executed.
385 Indicates that a vfork system call was executed.
387 vforkdone stop reason
388 Indicates that a vfork child of the specified process has executed
389 an exec or exit, allowing the vfork parent to resume execution.
391 fork-events and vfork-events features in qSupported
392 The qSupported packet allows GDB to request support for fork and
393 vfork events using new 'gdbfeatures' fork-events and vfork-events,
394 and the qSupported response can contain the corresponding
395 'stubfeatures'. Set and show commands can be used to display
396 whether these features are enabled.
398 * Extended-remote fork events
400 ** GDB now has support for fork events on extended-remote Linux
401 targets. For targets with Linux kernels 2.5.60 and later, this
402 enables follow-fork-mode and detach-on-fork for both fork and
403 vfork, as well as fork and vfork catchpoints.
405 * The info record command now shows the recording format and the
406 branch tracing configuration for the current thread when using
407 the btrace record target.
408 For the BTS format, it shows the ring buffer size.
410 * GDB now has support for DTrace USDT (Userland Static Defined
411 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
413 * GDB now supports access to vector registers on S/390 GNU/Linux
416 * Removed command line options
418 -xdb HP-UX XDB compatibility mode.
420 * Removed targets and native configurations
422 HP/PA running HP-UX hppa*-*-hpux*
423 Itanium running HP-UX ia64-*-hpux*
425 * New configure options
428 This configure option allows the user to build GDB with support for
429 Intel(R) Processor Trace (default: auto). This requires libipt.
431 --with-libipt-prefix=PATH
432 Specify the path to the version of libipt that GDB should use.
433 $PATH/include should contain the intel-pt.h header and
434 $PATH/lib should contain the libipt.so library.
436 *** Changes in GDB 7.9.1
440 ** Xmethods can now specify a result type.
442 *** Changes in GDB 7.9
444 * GDB now supports hardware watchpoints on x86 GNU Hurd.
448 ** You can now access frame registers from Python scripts.
449 ** New attribute 'producer' for gdb.Symtab objects.
450 ** gdb.Objfile objects have a new attribute "progspace",
451 which is the gdb.Progspace object of the containing program space.
452 ** gdb.Objfile objects have a new attribute "owner".
453 ** gdb.Objfile objects have a new attribute "build_id",
454 which is the build ID generated when the file was built.
455 ** gdb.Objfile objects have a new method "add_separate_debug_file".
456 ** A new event "gdb.clear_objfiles" has been added, triggered when
457 selecting a new file to debug.
458 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
459 ** New function gdb.lookup_objfile.
461 New events which are triggered when GDB modifies the state of the
464 ** gdb.events.inferior_call_pre: Function call is about to be made.
465 ** gdb.events.inferior_call_post: Function call has just been made.
466 ** gdb.events.memory_changed: A memory location has been altered.
467 ** gdb.events.register_changed: A register has been altered.
469 * New Python-based convenience functions:
471 ** $_caller_is(name [, number_of_frames])
472 ** $_caller_matches(regexp [, number_of_frames])
473 ** $_any_caller_is(name [, number_of_frames])
474 ** $_any_caller_matches(regexp [, number_of_frames])
476 * GDB now supports the compilation and injection of source code into
477 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
478 to compile the source code to object code, and if successful, inject
479 and execute that code within the current context of the inferior.
480 Currently the C language is supported. The commands used to
481 interface with this new feature are:
483 compile code [-raw|-r] [--] [source code]
484 compile file [-raw|-r] filename
488 demangle [-l language] [--] name
489 Demangle "name" in the specified language, or the current language
490 if elided. This command is renamed from the "maint demangle" command.
491 The latter is kept as a no-op to avoid "maint demangle" being interpreted
492 as "maint demangler-warning".
494 queue-signal signal-name-or-number
495 Queue a signal to be delivered to the thread when it is resumed.
497 add-auto-load-scripts-directory directory
498 Add entries to the list of directories from which to load auto-loaded
501 maint print user-registers
502 List all currently available "user" registers.
504 compile code [-r|-raw] [--] [source code]
505 Compile, inject, and execute in the inferior the executable object
506 code produced by compiling the provided source code.
508 compile file [-r|-raw] filename
509 Compile and inject into the inferior the executable object code
510 produced by compiling the source code stored in the filename
513 * On resume, GDB now always passes the signal the program had stopped
514 for to the thread the signal was sent to, even if the user changed
515 threads before resuming. Previously GDB would often (but not
516 always) deliver the signal to the thread that happens to be current
519 * Conversely, the "signal" command now consistently delivers the
520 requested signal to the current thread. GDB now asks for
521 confirmation if the program had stopped for a signal and the user
522 switched threads meanwhile.
524 * "breakpoint always-inserted" modes "off" and "auto" merged.
526 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
527 won't remove breakpoints from the target until all threads stop,
528 even in non-stop mode. The "auto" mode has been removed, and "off"
529 is now the default mode.
533 set debug symbol-lookup
534 show debug symbol-lookup
535 Control display of debugging info regarding symbol lookup.
539 ** The -list-thread-groups command outputs an exit-code field for
540 inferiors that have exited.
544 MIPS SDE mips*-sde*-elf*
548 Support for these obsolete configurations has been removed.
550 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
551 SGI Irix-5.x mips-*-irix5*
552 SGI Irix-6.x mips-*-irix6*
553 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
554 VAX running Ultrix vax-*-ultrix*
556 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
557 and "assf"), have been removed. Use the "sharedlibrary" command, or
558 its alias "share", instead.
560 *** Changes in GDB 7.8
562 * New command line options
565 This is an alias for the --data-directory option.
567 * GDB supports printing and modifying of variable length automatic arrays
568 as specified in ISO C99.
570 * The ARM simulator now supports instruction level tracing
571 with or without disassembly.
575 GDB now has support for scripting using Guile. Whether this is
576 available is determined at configure time.
577 Guile version 2.0 or greater is required.
578 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
580 * New commands (for set/show, see "New options" below)
584 Invoke CODE by passing it to the Guile interpreter.
588 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
590 info auto-load guile-scripts [regexp]
591 Print the list of automatically loaded Guile scripts.
593 * The source command is now capable of sourcing Guile scripts.
594 This feature is dependent on the debugger being built with Guile support.
598 set print symbol-loading (off|brief|full)
599 show print symbol-loading
600 Control whether to print informational messages when loading symbol
601 information for a file. The default is "full", but when debugging
602 programs with large numbers of shared libraries the amount of output
605 set guile print-stack (none|message|full)
606 show guile print-stack
607 Show a stack trace when an error is encountered in a Guile script.
609 set auto-load guile-scripts (on|off)
610 show auto-load guile-scripts
611 Control auto-loading of Guile script files.
613 maint ada set ignore-descriptive-types (on|off)
614 maint ada show ignore-descriptive-types
615 Control whether the debugger should ignore descriptive types in Ada
616 programs. The default is not to ignore the descriptive types. See
617 the user manual for more details on descriptive types and the intended
618 usage of this option.
620 set auto-connect-native-target
622 Control whether GDB is allowed to automatically connect to the
623 native target for the run, attach, etc. commands when not connected
624 to any target yet. See also "target native" below.
626 set record btrace replay-memory-access (read-only|read-write)
627 show record btrace replay-memory-access
628 Control what memory accesses are allowed during replay.
630 maint set target-async (on|off)
631 maint show target-async
632 This controls whether GDB targets operate in synchronous or
633 asynchronous mode. Normally the default is asynchronous, if it is
634 available; but this can be changed to more easily debug problems
635 occurring only in synchronous mode.
637 set mi-async (on|off)
639 Control whether MI asynchronous mode is preferred. This supersedes
640 "set target-async" of previous GDB versions.
642 * "set target-async" is deprecated as a CLI option and is now an alias
643 for "set mi-async" (only puts MI into async mode).
645 * Background execution commands (e.g., "c&", "s&", etc.) are now
646 possible ``out of the box'' if the target supports them. Previously
647 the user would need to explicitly enable the possibility with the
648 "set target-async on" command.
650 * New features in the GDB remote stub, GDBserver
652 ** New option --debug-format=option1[,option2,...] allows one to add
653 additional text to each output. At present only timestamps
654 are supported: --debug-format=timestamps.
655 Timestamps can also be turned on with the
656 "monitor set debug-format timestamps" command from GDB.
658 * The 'record instruction-history' command now starts counting instructions
659 at one. This also affects the instruction ranges reported by the
660 'record function-call-history' command when given the /i modifier.
662 * The command 'record function-call-history' supports a new modifier '/c' to
663 indent the function names based on their call stack depth.
664 The fields for the '/i' and '/l' modifier have been reordered.
665 The source line range is now prefixed with 'at'.
666 The instruction range is now prefixed with 'inst'.
667 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
668 "record instruction-history" and "list" commands.
670 * The ranges given as arguments to the 'record function-call-history' and
671 'record instruction-history' commands are now inclusive.
673 * The btrace record target now supports the 'record goto' command.
674 For locations inside the execution trace, the back trace is computed
675 based on the information stored in the execution trace.
677 * The btrace record target supports limited reverse execution and replay.
678 The target does not record data and therefore does not allow reading
681 * The "catch syscall" command now works on s390*-linux* targets.
683 * The "compare-sections" command is no longer specific to target
684 remote. It now works with all targets.
686 * All native targets are now consistently called "native".
687 Consequently, the "target child", "target GNU", "target djgpp",
688 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
689 commands have been replaced with "target native". The QNX/NTO port
690 leaves the "procfs" target in place and adds a "native" target for
691 consistency with other ports. The impact on users should be minimal
692 as these commands previously either throwed an error, or were
693 no-ops. The target's name is visible in the output of the following
694 commands: "help target", "info target", "info files", "maint print
697 * The "target native" command now connects to the native target. This
698 can be used to launch native programs even when "set
699 auto-connect-native-target" is set to off.
701 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
703 * Support for Intel(R) AVX-512 registers on GNU/Linux.
704 Support displaying and modifying Intel(R) AVX-512 registers
705 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
709 qXfer:btrace:read's annex
710 The qXfer:btrace:read packet supports a new annex 'delta' to read
711 branch trace incrementally.
715 ** Valid Python operations on gdb.Value objects representing
716 structs/classes invoke the corresponding overloaded operators if
718 ** New `Xmethods' feature in the Python API. Xmethods are
719 additional methods or replacements for existing methods of a C++
720 class. This feature is useful for those cases where a method
721 defined in C++ source code could be inlined or optimized out by
722 the compiler, making it unavailable to GDB.
725 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
727 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
728 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
729 its alias "share", instead.
731 * The commands "set remotebaud" and "show remotebaud" are no longer
732 supported. Use "set serial baud" and "show serial baud" (respectively)
737 ** A new option "-gdb-set mi-async" replaces "-gdb-set
738 target-async". The latter is left as a deprecated alias of the
739 former for backward compatibility. If the target supports it,
740 CLI background execution commands are now always possible by
741 default, independently of whether the frontend stated a
742 preference for asynchronous execution with "-gdb-set mi-async".
743 Previously "-gdb-set target-async off" affected both MI execution
744 commands and CLI execution commands.
746 *** Changes in GDB 7.7
748 * Improved support for process record-replay and reverse debugging on
749 arm*-linux* targets. Support for thumb32 and syscall instruction
750 recording has been added.
752 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
754 * GDB now supports Fission DWP file format version 2.
755 http://gcc.gnu.org/wiki/DebugFission
757 * New convenience function "$_isvoid", to check whether an expression
758 is void. A void expression is an expression where the type of the
759 result is "void". For example, some convenience variables may be
760 "void" when evaluated (e.g., "$_exitcode" before the execution of
761 the program being debugged; or an undefined convenience variable).
762 Another example, when calling a function whose return type is
765 * The "maintenance print objfiles" command now takes an optional regexp.
767 * The "catch syscall" command now works on arm*-linux* targets.
769 * GDB now consistently shows "<not saved>" when printing values of
770 registers the debug info indicates have not been saved in the frame
771 and there's nowhere to retrieve them from
772 (callee-saved/call-clobbered registers):
777 (gdb) info registers rax
780 Before, the former would print "<optimized out>", and the latter
781 "*value not available*".
783 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
788 ** Frame filters and frame decorators have been added.
789 ** Temporary breakpoints are now supported.
790 ** Line tables representation has been added.
791 ** New attribute 'parent_type' for gdb.Field objects.
792 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
793 ** New attribute 'name' for gdb.Type objects.
797 Nios II ELF nios2*-*-elf
798 Nios II GNU/Linux nios2*-*-linux
799 Texas Instruments MSP430 msp430*-*-elf
801 * Removed native configurations
803 Support for these a.out NetBSD and OpenBSD obsolete configurations has
804 been removed. ELF variants of these configurations are kept supported.
806 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
807 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
808 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
809 i[34567]86-*-openbsd3.[0-3]
810 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
811 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
812 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
816 Like "catch throw", but catches a re-thrown exception.
818 Renamed from old "maint check-symtabs".
820 Perform consistency checks on symtabs.
822 Expand symtabs matching an optional regexp.
825 Display the details of GDB configure-time options.
827 maint set|show per-command
828 maint set|show per-command space
829 maint set|show per-command time
830 maint set|show per-command symtab
831 Enable display of per-command gdb resource usage.
833 remove-symbol-file FILENAME
834 remove-symbol-file -a ADDRESS
835 Remove a symbol file added via add-symbol-file. The file to remove
836 can be identified by its filename or by an address that lies within
837 the boundaries of this symbol file in memory.
840 info exceptions REGEXP
841 Display the list of Ada exceptions defined in the program being
842 debugged. If provided, only the exceptions whose names match REGEXP
847 set debug symfile off|on
849 Control display of debugging info regarding reading symbol files and
850 symbol tables within those files
852 set print raw frame-arguments
853 show print raw frame-arguments
854 Set/show whether to print frame arguments in raw mode,
855 disregarding any defined pretty-printers.
857 set remote trace-status-packet
858 show remote trace-status-packet
859 Set/show the use of remote protocol qTStatus packet.
863 Control display of debugging messages related to Nios II targets.
867 Control whether target-assisted range stepping is enabled.
869 set startup-with-shell
870 show startup-with-shell
871 Specifies whether Unix child processes are started via a shell or
876 Use the target memory cache for accesses to the code segment. This
877 improves performance of remote debugging (particularly disassembly).
879 * You can now use a literal value 'unlimited' for options that
880 interpret 0 or -1 as meaning "unlimited". E.g., "set
881 trace-buffer-size unlimited" is now an alias for "set
882 trace-buffer-size -1" and "set height unlimited" is now an alias for
885 * The "set debug symtab-create" debugging option of GDB has been changed to
886 accept a verbosity level. 0 means "off", 1 provides basic debugging
887 output, and values of 2 or greater provides more verbose output.
889 * New command-line options
891 Display the details of GDB configure-time options.
893 * The command 'tsave' can now support new option '-ctf' to save trace
894 buffer in Common Trace Format.
896 * Newly installed $prefix/bin/gcore acts as a shell interface for the
899 * GDB now implements the the C++ 'typeid' operator.
901 * The new convenience variable $_exception holds the exception being
902 thrown or caught at an exception-related catchpoint.
904 * The exception-related catchpoints, like "catch throw", now accept a
905 regular expression which can be used to filter exceptions by type.
907 * The new convenience variable $_exitsignal is automatically set to
908 the terminating signal number when the program being debugged dies
909 due to an uncaught signal.
913 ** All MI commands now accept an optional "--language" option.
914 Support for this feature can be verified by using the "-list-features"
915 command, which should contain "language-option".
917 ** The new command -info-gdb-mi-command allows the user to determine
918 whether a GDB/MI command is supported or not.
920 ** The "^error" result record returned when trying to execute an undefined
921 GDB/MI command now provides a variable named "code" whose content is the
922 "undefined-command" error code. Support for this feature can be verified
923 by using the "-list-features" command, which should contain
924 "undefined-command-error-code".
926 ** The -trace-save MI command can optionally save trace buffer in Common
929 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
931 ** The command -data-list-register-values now accepts an optional
932 "--skip-unavailable" option. When used, only the available registers
935 ** The new command -trace-frame-collected dumps collected variables,
936 computed expressions, tvars, memory and registers in a traceframe.
938 ** The commands -stack-list-locals, -stack-list-arguments and
939 -stack-list-variables now accept an option "--skip-unavailable".
940 When used, only the available locals or arguments are displayed.
942 ** The -exec-run command now accepts an optional "--start" option.
943 When used, the command follows the same semantics as the "start"
944 command, stopping the program's execution at the start of its
945 main subprogram. Support for this feature can be verified using
946 the "-list-features" command, which should contain
947 "exec-run-start-option".
949 ** The new commands -catch-assert and -catch-exceptions insert
950 catchpoints stopping the program when Ada exceptions are raised.
952 ** The new command -info-ada-exceptions provides the equivalent of
953 the new "info exceptions" command.
955 * New system-wide configuration scripts
956 A GDB installation now provides scripts suitable for use as system-wide
957 configuration scripts for the following systems:
961 * GDB now supports target-assigned range stepping with remote targets.
962 This improves the performance of stepping source lines by reducing
963 the number of control packets from/to GDB. See "New remote packets"
966 * GDB now understands the element 'tvar' in the XML traceframe info.
967 It has the id of the collected trace state variables.
969 * On S/390 targets that provide the transactional-execution feature,
970 the program interruption transaction diagnostic block (TDB) is now
971 represented as a number of additional "registers" in GDB.
977 The vCont packet supports a new 'r' action, that tells the remote
978 stub to step through an address range itself, without GDB
979 involvemement at each single-step.
981 qXfer:libraries-svr4:read's annex
982 The previously unused annex of the qXfer:libraries-svr4:read packet
983 is now used to support passing an argument list. The remote stub
984 reports support for this argument list to GDB's qSupported query.
985 The defined arguments are "start" and "prev", used to reduce work
986 necessary for library list updating, resulting in significant
989 * New features in the GDB remote stub, GDBserver
991 ** GDBserver now supports target-assisted range stepping. Currently
992 enabled on x86/x86_64 GNU/Linux targets.
994 ** GDBserver now adds element 'tvar' in the XML in the reply to
995 'qXfer:traceframe-info:read'. It has the id of the collected
996 trace state variables.
998 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1001 * New 'z' formatter for printing and examining memory, this displays the
1002 value as hexadecimal zero padded on the left to the size of the type.
1004 * GDB can now use Windows x64 unwinding data.
1006 * The "set remotebaud" command has been replaced by "set serial baud".
1007 Similarly, "show remotebaud" has been replaced by "show serial baud".
1008 The "set remotebaud" and "show remotebaud" commands are still available
1009 to provide backward compatibility with older versions of GDB.
1011 *** Changes in GDB 7.6
1013 * Target record has been renamed to record-full.
1014 Record/replay is now enabled with the "record full" command.
1015 This also affects settings that are associated with full record/replay
1016 that have been moved from "set/show record" to "set/show record full":
1018 set|show record full insn-number-max
1019 set|show record full stop-at-limit
1020 set|show record full memory-query
1022 * A new record target "record-btrace" has been added. The new target
1023 uses hardware support to record the control-flow of a process. It
1024 does not support replaying the execution, but it implements the
1025 below new commands for investigating the recorded execution log.
1026 This new recording method can be enabled using:
1030 The "record-btrace" target is only available on Intel Atom processors
1031 and requires a Linux kernel 2.6.32 or later.
1033 * Two new commands have been added for record/replay to give information
1034 about the recorded execution without having to replay the execution.
1035 The commands are only supported by "record btrace".
1037 record instruction-history prints the execution history at
1038 instruction granularity
1040 record function-call-history prints the execution history at
1041 function granularity
1043 * New native configurations
1045 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1046 FreeBSD/powerpc powerpc*-*-freebsd
1047 x86_64/Cygwin x86_64-*-cygwin*
1048 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1052 ARM AArch64 aarch64*-*-elf
1053 ARM AArch64 GNU/Linux aarch64*-*-linux
1054 Lynx 178 PowerPC powerpc-*-lynx*178
1055 x86_64/Cygwin x86_64-*-cygwin*
1056 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1058 * If the configured location of system.gdbinit file (as given by the
1059 --with-system-gdbinit option at configure time) is in the
1060 data-directory (as specified by --with-gdb-datadir at configure
1061 time) or in one of its subdirectories, then GDB will look for the
1062 system-wide init file in the directory specified by the
1063 --data-directory command-line option.
1065 * New command line options:
1067 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1068 other initialization files, unlike -nx which disables all of them.
1070 * Removed command line options
1072 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1075 * The 'ptype' and 'whatis' commands now accept an argument to control
1078 * 'info proc' now works on some core files.
1082 ** Vectors can be created with gdb.Type.vector.
1084 ** Python's atexit.register now works in GDB.
1086 ** Types can be pretty-printed via a Python API.
1088 ** Python 3 is now supported (in addition to Python 2.4 or later)
1090 ** New class gdb.Architecture exposes GDB's internal representation
1091 of architecture in the Python API.
1093 ** New method Frame.architecture returns the gdb.Architecture object
1094 corresponding to the frame's architecture.
1096 * New Python-based convenience functions:
1098 ** $_memeq(buf1, buf2, length)
1099 ** $_streq(str1, str2)
1101 ** $_regex(str, regex)
1103 * The 'cd' command now defaults to using '~' (the home directory) if not
1106 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1107 default for GCC since November 2000.
1109 * The command 'forward-search' can now be abbreviated as 'fo'.
1111 * The command 'info tracepoints' can now display 'installed on target'
1112 or 'not installed on target' for each non-pending location of tracepoint.
1114 * New configure options
1116 --enable-libmcheck/--disable-libmcheck
1117 By default, development versions are built with -lmcheck on hosts
1118 that support it, in order to help track memory corruption issues.
1119 Release versions, on the other hand, are built without -lmcheck
1120 by default. The --enable-libmcheck/--disable-libmcheck configure
1121 options allow the user to override that default.
1122 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1123 This configure option allows the user to build GDB with
1124 libbabeltrace using which GDB can read Common Trace Format data.
1126 * New commands (for set/show, see "New options" below)
1129 Catch signals. This is similar to "handle", but allows commands and
1130 conditions to be attached.
1133 List the BFDs known to GDB.
1135 python-interactive [command]
1137 Start a Python interactive prompt, or evaluate the optional command
1138 and print the result of expressions.
1141 "py" is a new alias for "python".
1143 enable type-printer [name]...
1144 disable type-printer [name]...
1145 Enable or disable type printers.
1149 ** For the Renesas Super-H architecture, the "regs" command has been removed
1150 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1155 set print type methods (on|off)
1156 show print type methods
1157 Control whether method declarations are displayed by "ptype".
1158 The default is to show them.
1160 set print type typedefs (on|off)
1161 show print type typedefs
1162 Control whether typedef definitions are displayed by "ptype".
1163 The default is to show them.
1165 set filename-display basename|relative|absolute
1166 show filename-display
1167 Control the way in which filenames is displayed.
1168 The default is "relative", which preserves previous behavior.
1170 set trace-buffer-size
1171 show trace-buffer-size
1172 Request target to change the size of trace buffer.
1174 set remote trace-buffer-size-packet auto|on|off
1175 show remote trace-buffer-size-packet
1176 Control the use of the remote protocol `QTBuffer:size' packet.
1180 Control display of debugging messages related to ARM AArch64.
1183 set debug coff-pe-read
1184 show debug coff-pe-read
1185 Control display of debugging messages related to reading of COFF/PE
1190 Control display of debugging messages related to Mach-O symbols
1193 set debug notification
1194 show debug notification
1195 Control display of debugging info for async remote notification.
1199 ** Command parameter changes are now notified using new async record
1200 "=cmd-param-changed".
1201 ** Trace frame changes caused by command "tfind" are now notified using
1202 new async record "=traceframe-changed".
1203 ** The creation, deletion and modification of trace state variables
1204 are now notified using new async records "=tsv-created",
1205 "=tsv-deleted" and "=tsv-modified".
1206 ** The start and stop of process record are now notified using new
1207 async record "=record-started" and "=record-stopped".
1208 ** Memory changes are now notified using new async record
1210 ** The data-disassemble command response will include a "fullname" field
1211 containing the absolute file name when source has been requested.
1212 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1213 command, to allow pattern filling of memory areas.
1214 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1215 library load/unload events.
1216 ** The response to breakpoint commands and breakpoint async records
1217 includes an "installed" field containing a boolean state about each
1218 non-pending tracepoint location is whether installed on target or not.
1219 ** Output of the "-trace-status" command includes a "trace-file" field
1220 containing the name of the trace file being examined. This field is
1221 optional, and only present when examining a trace file.
1222 ** The "fullname" field is now always present along with the "file" field,
1223 even if the file cannot be found by GDB.
1225 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1226 You must have the LZMA library available when configuring GDB for this
1227 feature to be enabled. For more information, see:
1228 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1230 * New remote packets
1233 Set the size of trace buffer. The remote stub reports support for this
1234 packet to gdb's qSupported query.
1237 Enable Branch Trace Store (BTS)-based branch tracing for the current
1238 thread. The remote stub reports support for this packet to gdb's
1242 Disable branch tracing for the current thread. The remote stub reports
1243 support for this packet to gdb's qSupported query.
1246 Read the traced branches for the current thread. The remote stub
1247 reports support for this packet to gdb's qSupported query.
1249 *** Changes in GDB 7.5
1251 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1252 for more x32 ABI info.
1254 * GDB now supports access to MIPS DSP registers on Linux targets.
1256 * GDB now supports debugging microMIPS binaries.
1258 * The "info os" command on GNU/Linux can now display information on
1259 several new classes of objects managed by the operating system:
1260 "info os procgroups" lists process groups
1261 "info os files" lists file descriptors
1262 "info os sockets" lists internet-domain sockets
1263 "info os shm" lists shared-memory regions
1264 "info os semaphores" lists semaphores
1265 "info os msg" lists message queues
1266 "info os modules" lists loaded kernel modules
1268 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1269 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1270 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1271 options and inspect the probe arguments using the new $_probe_arg family
1272 of convenience variables. You can obtain more information about SystemTap
1273 in <http://sourceware.org/systemtap/>.
1275 * GDB now supports reversible debugging on ARM, it allows you to
1276 debug basic ARM and THUMB instructions, and provides
1277 record/replay support.
1279 * The option "symbol-reloading" has been deleted as it is no longer used.
1283 ** GDB commands implemented in Python can now be put in command class
1286 ** The "maint set python print-stack on|off" is now deleted.
1288 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1289 apply "flag enum"-style pretty-printing to any enum.
1291 ** gdb.lookup_symbol can now work when there is no current frame.
1293 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1294 the source at which the symbol was defined.
1296 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1297 method 'value'. The former indicates whether the symbol needs a
1298 frame in order to compute its value, and the latter computes the
1301 ** A new method 'referenced_value' on gdb.Value objects which can
1302 dereference pointer as well as C++ reference values.
1304 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1305 which return the global and static blocks (as gdb.Block objects),
1306 of the underlying symbol table, respectively.
1308 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1309 object associated with a PC value.
1311 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1312 of the address range occupied by code for the current source line.
1314 * Go language support.
1315 GDB now supports debugging programs written in the Go programming
1318 * GDBserver now supports stdio connections.
1319 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1321 * The binary "gdbtui" can no longer be built or installed.
1322 Use "gdb -tui" instead.
1324 * GDB will now print "flag" enums specially. A flag enum is one where
1325 all the enumerator values have no bits in common when pairwise
1326 "and"ed. When printing a value whose type is a flag enum, GDB will
1327 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1328 (gdb) print (enum E) 3
1331 * The filename part of a linespec will now match trailing components
1332 of a source file name. For example, "break gcc/expr.c:1000" will
1333 now set a breakpoint in build/gcc/expr.c, but not
1334 build/libcpp/expr.c.
1336 * The "info proc" and "generate-core-file" commands will now also
1337 work on remote targets connected to GDBserver on Linux.
1339 * The command "info catch" has been removed. It has been disabled
1340 since December 2007.
1342 * The "catch exception" and "catch assert" commands now accept
1343 a condition at the end of the command, much like the "break"
1344 command does. For instance:
1346 (gdb) catch exception Constraint_Error if Barrier = True
1348 Previously, it was possible to add a condition to such catchpoints,
1349 but it had to be done as a second step, after the catchpoint had been
1350 created, using the "condition" command.
1352 * The "info static-tracepoint-marker" command will now also work on
1353 native Linux targets with in-process agent.
1355 * GDB can now set breakpoints on inlined functions.
1357 * The .gdb_index section has been updated to include symbols for
1358 inlined functions. GDB will ignore older .gdb_index sections by
1359 default, which could cause symbol files to be loaded more slowly
1360 until their .gdb_index sections can be recreated. The new command
1361 "set use-deprecated-index-sections on" will cause GDB to use any older
1362 .gdb_index sections it finds. This will restore performance, but the
1363 ability to set breakpoints on inlined functions will be lost in symbol
1364 files with older .gdb_index sections.
1366 The .gdb_index section has also been updated to record more information
1367 about each symbol. This speeds up the "info variables", "info functions"
1368 and "info types" commands when used with programs having the .gdb_index
1369 section, as well as speeding up debugging with shared libraries using
1370 the .gdb_index section.
1372 * Ada support for GDB/MI Variable Objects has been added.
1374 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1379 ** New command -info-os is the MI equivalent of "info os".
1381 ** Output logs ("set logging" and related) now include MI output.
1385 ** "set use-deprecated-index-sections on|off"
1386 "show use-deprecated-index-sections on|off"
1387 Controls the use of deprecated .gdb_index sections.
1389 ** "catch load" and "catch unload" can be used to stop when a shared
1390 library is loaded or unloaded, respectively.
1392 ** "enable count" can be used to auto-disable a breakpoint after
1395 ** "info vtbl" can be used to show the virtual method tables for
1396 C++ and Java objects.
1398 ** "explore" and its sub commands "explore value" and "explore type"
1399 can be used to recursively explore values and types of
1400 expressions. These commands are available only if GDB is
1401 configured with '--with-python'.
1403 ** "info auto-load" shows status of all kinds of auto-loaded files,
1404 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1405 sequences of commands files, "info auto-load python-scripts"
1406 shows status of auto-loading Python script files,
1407 "info auto-load local-gdbinit" shows status of loading init file
1408 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1409 status of inferior specific thread debugging shared library loading.
1411 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1412 and "show auto-load-scripts" commands have been deprecated, use their
1413 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1414 and "show auto-load python-scripts" counterparts instead.
1416 ** "dprintf location,format,args..." creates a dynamic printf, which
1417 is basically a breakpoint that does a printf and immediately
1418 resumes your program's execution, so it is like a printf that you
1419 can insert dynamically at runtime instead of at compiletime.
1421 ** "set print symbol"
1423 Controls whether GDB attempts to display the symbol, if any,
1424 corresponding to addresses it prints. This defaults to "on", but
1425 you can set it to "off" to restore GDB's previous behavior.
1427 * Deprecated commands
1429 ** For the Renesas Super-H architecture, the "regs" command has been
1430 deprecated, and "info all-registers" should be used instead.
1434 Renesas RL78 rl78-*-elf
1435 HP OpenVMS ia64 ia64-hp-openvms*
1437 * GDBserver supports evaluation of breakpoint conditions. When
1438 support is advertised by GDBserver, GDB may be told to send the
1439 breakpoint conditions in bytecode form to GDBserver. GDBserver
1440 will only report the breakpoint trigger to GDB when its condition
1445 set mips compression
1446 show mips compression
1447 Select the compressed ISA encoding used in functions that have no symbol
1448 information available. The encoding can be set to either of:
1451 and is updated automatically from ELF file flags if available.
1453 set breakpoint condition-evaluation
1454 show breakpoint condition-evaluation
1455 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1456 GDBserver ("target"). Default option "auto" chooses the most efficient
1458 This option can improve debugger efficiency depending on the speed of the
1462 Disable auto-loading globally.
1465 Show auto-loading setting of all kinds of auto-loaded files.
1467 set auto-load gdb-scripts on|off
1468 show auto-load gdb-scripts
1469 Control auto-loading of GDB canned sequences of commands files.
1471 set auto-load python-scripts on|off
1472 show auto-load python-scripts
1473 Control auto-loading of Python script files.
1475 set auto-load local-gdbinit on|off
1476 show auto-load local-gdbinit
1477 Control loading of init file (.gdbinit) from current directory.
1479 set auto-load libthread-db on|off
1480 show auto-load libthread-db
1481 Control auto-loading of inferior specific thread debugging shared library.
1483 set auto-load scripts-directory <dir1>[:<dir2>...]
1484 show auto-load scripts-directory
1485 Set a list of directories from which to load auto-loaded scripts.
1486 Automatically loaded Python scripts and GDB scripts are located in one
1487 of the directories listed by this option.
1488 The delimiter (':' above) may differ according to the host platform.
1490 set auto-load safe-path <dir1>[:<dir2>...]
1491 show auto-load safe-path
1492 Set a list of directories from which it is safe to auto-load files.
1493 The delimiter (':' above) may differ according to the host platform.
1495 set debug auto-load on|off
1496 show debug auto-load
1497 Control display of debugging info for auto-loading the files above.
1499 set dprintf-style gdb|call|agent
1501 Control the way in which a dynamic printf is performed; "gdb"
1502 requests a GDB printf command, while "call" causes dprintf to call a
1503 function in the inferior. "agent" requests that the target agent
1504 (such as GDBserver) do the printing.
1506 set dprintf-function <expr>
1507 show dprintf-function
1508 set dprintf-channel <expr>
1509 show dprintf-channel
1510 Set the function and optional first argument to the call when using
1511 the "call" style of dynamic printf.
1513 set disconnected-dprintf on|off
1514 show disconnected-dprintf
1515 Control whether agent-style dynamic printfs continue to be in effect
1516 after GDB disconnects.
1518 * New configure options
1520 --with-auto-load-dir
1521 Configure default value for the 'set auto-load scripts-directory'
1522 setting above. It defaults to '$debugdir:$datadir/auto-load',
1523 $debugdir representing global debugging info directories (available
1524 via 'show debug-file-directory') and $datadir representing GDB's data
1525 directory (available via 'show data-directory').
1527 --with-auto-load-safe-path
1528 Configure default value for the 'set auto-load safe-path' setting
1529 above. It defaults to the --with-auto-load-dir setting.
1531 --without-auto-load-safe-path
1532 Set 'set auto-load safe-path' to '/', effectively disabling this
1535 * New remote packets
1537 z0/z1 conditional breakpoints extension
1539 The z0/z1 breakpoint insertion packets have been extended to carry
1540 a list of conditional expressions over to the remote stub depending on the
1541 condition evaluation mode. The use of this extension can be controlled
1542 via the "set remote conditional-breakpoints-packet" command.
1546 Specify the signals which the remote stub may pass to the debugged
1547 program without GDB involvement.
1549 * New command line options
1551 --init-command=FILE, -ix Like --command, -x but execute it
1552 before loading inferior.
1553 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1554 execute it before loading inferior.
1556 *** Changes in GDB 7.4
1558 * GDB now handles ambiguous linespecs more consistently; the existing
1559 FILE:LINE support has been expanded to other types of linespecs. A
1560 breakpoint will now be set on all matching locations in all
1561 inferiors, and locations will be added or removed according to
1564 * GDB now allows you to skip uninteresting functions and files when
1565 stepping with the "skip function" and "skip file" commands.
1567 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1568 and "show remote hardware-watchpoint-length-limit". These allows to
1569 set or show the maximum length limit (in bytes) of a remote
1570 target hardware watchpoint.
1572 This allows e.g. to use "unlimited" hardware watchpoints with the
1573 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1574 watchpoints are slower than real hardware watchpoints but are
1575 significantly faster than gdb software watchpoints.
1579 ** The register_pretty_printer function in module gdb.printing now takes
1580 an optional `replace' argument. If True, the new printer replaces any
1583 ** The "maint set python print-stack on|off" command has been
1584 deprecated and will be deleted in GDB 7.5.
1585 A new command: "set python print-stack none|full|message" has
1586 replaced it. Additionally, the default for "print-stack" is
1587 now "message", which just prints the error message without
1590 ** A prompt substitution hook (prompt_hook) is now available to the
1593 ** A new Python module, gdb.prompt has been added to the GDB Python
1594 modules library. This module provides functionality for
1595 escape sequences in prompts (used by set/show
1596 extended-prompt). These escape sequences are replaced by their
1597 corresponding value.
1599 ** Python commands and convenience-functions located in
1600 'data-directory'/python/gdb/command and
1601 'data-directory'/python/gdb/function are now automatically loaded
1604 ** Blocks now provide four new attributes. global_block and
1605 static_block will return the global and static blocks
1606 respectively. is_static and is_global are boolean attributes
1607 that indicate if the block is one of those two types.
1609 ** Symbols now provide the "type" attribute, the type of the symbol.
1611 ** The "gdb.breakpoint" function has been deprecated in favor of
1614 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1615 of a function. This class is based on the "finish" command
1616 available in the CLI.
1618 ** Type objects for struct and union types now allow access to
1619 the fields using standard Python dictionary (mapping) methods.
1620 For example, "some_type['myfield']" now works, as does
1621 "some_type.items()".
1623 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1626 ** A new function, "deep_items" has been added to the gdb.types
1627 module in the GDB Python modules library. This function returns
1628 an iterator over the fields of a struct or union type. Unlike
1629 the standard Python "iteritems" method, it will recursively traverse
1630 any anonymous fields.
1634 ** "*stopped" events can report several new "reason"s, such as
1637 ** Breakpoint changes are now notified using new async records, like
1638 "=breakpoint-modified".
1640 ** New command -ada-task-info.
1642 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1643 $sdir specifies the default system locations of shared libraries.
1644 $pdir specifies the directory where the libpthread used by the application
1647 GDB no longer looks in $sdir and $pdir after it has searched the directories
1648 mentioned in libthread-db-search-path. If you want to search those
1649 directories, they must be specified in libthread-db-search-path.
1650 The default value of libthread-db-search-path on GNU/Linux and Solaris
1651 systems is now "$sdir:$pdir".
1653 $pdir is not supported by gdbserver, it is currently ignored.
1654 $sdir is supported by gdbserver.
1656 * New configure option --with-iconv-bin.
1657 When using the internationalization support like the one in the GNU C
1658 library, GDB will invoke the "iconv" program to get a list of supported
1659 character sets. If this program lives in a non-standard location, one can
1660 use this option to specify where to find it.
1662 * When natively debugging programs on PowerPC BookE processors running
1663 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1664 watchpoints, which specify a mask in addition to an address to watch.
1665 The mask specifies that some bits of an address (the bits which are
1666 reset in the mask) should be ignored when matching the address accessed
1667 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1668 section in the user manual for more details.
1670 * The new option --once causes GDBserver to stop listening for connections once
1671 the first connection is made. The listening port used by GDBserver will
1672 become available after that.
1674 * New commands "info macros" and "alias" have been added.
1676 * New function parameters suffix @entry specifies value of function parameter
1677 at the time the function got called. Entry values are available only since
1683 "!" is now an alias of the "shell" command.
1684 Note that no space is needed between "!" and SHELL COMMAND.
1688 watch EXPRESSION mask MASK_VALUE
1689 The watch command now supports the mask argument which allows creation
1690 of masked watchpoints, if the current architecture supports this feature.
1692 info auto-load-scripts [REGEXP]
1693 This command was formerly named "maintenance print section-scripts".
1694 It is now generally useful and is no longer a maintenance-only command.
1696 info macro [-all] [--] MACRO
1697 The info macro command has new options `-all' and `--'. The first for
1698 printing all definitions of a macro. The second for explicitly specifying
1699 the end of arguments and the beginning of the macro name in case the macro
1700 name starts with a hyphen.
1702 collect[/s] EXPRESSIONS
1703 The tracepoint collect command now takes an optional modifier "/s"
1704 that directs it to dereference pointer-to-character types and
1705 collect the bytes of memory up to a zero byte. The behavior is
1706 similar to what you see when you use the regular print command on a
1707 string. An optional integer following the "/s" sets a bound on the
1708 number of bytes that will be collected.
1711 The trace start command now interprets any supplied arguments as a
1712 note to be recorded with the trace run, with an effect similar to
1713 setting the variable trace-notes.
1716 The trace stop command now interprets any arguments as a note to be
1717 mentioned along with the tstatus report that the trace was stopped
1718 with a command. The effect is similar to setting the variable
1721 * Tracepoints can now be enabled and disabled at any time after a trace
1722 experiment has been started using the standard "enable" and "disable"
1723 commands. It is now possible to start a trace experiment with no enabled
1724 tracepoints; GDB will display a warning, but will allow the experiment to
1725 begin, assuming that tracepoints will be enabled as needed while the trace
1728 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1729 locations with 4-byte instructions, when they were previously
1730 limited to locations with instructions of 5 bytes or longer.
1734 set debug dwarf2-read
1735 show debug dwarf2-read
1736 Turns on or off display of debugging messages related to reading
1737 DWARF debug info. The default is off.
1739 set debug symtab-create
1740 show debug symtab-create
1741 Turns on or off display of debugging messages related to symbol table
1742 creation. The default is off.
1745 show extended-prompt
1746 Set the GDB prompt, and allow escape sequences to be inserted to
1747 display miscellaneous information (see 'help set extended-prompt'
1748 for the list of sequences). This prompt (and any information
1749 accessed through the escape sequences) is updated every time the
1750 prompt is displayed.
1752 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1753 show print entry-values
1754 Set printing of frame argument values at function entry. In some cases
1755 GDB can determine the value of function argument which was passed by the
1756 function caller, even if the value was modified inside the called function.
1758 set debug entry-values
1759 show debug entry-values
1760 Control display of debugging info for determining frame argument values at
1761 function entry and virtual tail call frames.
1763 set basenames-may-differ
1764 show basenames-may-differ
1765 Set whether a source file may have multiple base names.
1766 (A "base name" is the name of a file with the directory part removed.
1767 Example: The base name of "/home/user/hello.c" is "hello.c".)
1768 If set, GDB will canonicalize file names (e.g., expand symlinks)
1769 before comparing them. Canonicalization is an expensive operation,
1770 but it allows the same file be known by more than one base name.
1771 If not set (the default), all source files are assumed to have just
1772 one base name, and gdb will do file name comparisons more efficiently.
1778 Set a user name and notes for the current and any future trace runs.
1779 This is useful for long-running and/or disconnected traces, to
1780 inform others (or yourself) as to who is running the trace, supply
1781 contact information, or otherwise explain what is going on.
1783 set trace-stop-notes
1784 show trace-stop-notes
1785 Set a note attached to the trace run, that is displayed when the
1786 trace has been stopped by a tstop command. This is useful for
1787 instance as an explanation, if you are stopping a trace run that was
1788 started by someone else.
1790 * New remote packets
1794 Dynamically enable a tracepoint in a started trace experiment.
1798 Dynamically disable a tracepoint in a started trace experiment.
1802 Set the user and notes of the trace run.
1806 Query the current status of a tracepoint.
1810 Query the minimum length of instruction at which a fast tracepoint may
1813 * Dcache size (number of lines) and line-size are now runtime-configurable
1814 via "set dcache line" and "set dcache line-size" commands.
1818 Texas Instruments TMS320C6x tic6x-*-*
1822 Renesas RL78 rl78-*-elf
1824 *** Changes in GDB 7.3.1
1826 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1828 *** Changes in GDB 7.3
1830 * GDB has a new command: "thread find [REGEXP]".
1831 It finds the thread id whose name, target id, or thread extra info
1832 matches the given regular expression.
1834 * The "catch syscall" command now works on mips*-linux* targets.
1836 * The -data-disassemble MI command now supports modes 2 and 3 for
1837 dumping the instruction opcodes.
1839 * New command line options
1841 -data-directory DIR Specify DIR as the "data-directory".
1842 This is mostly for testing purposes.
1844 * The "maint set python auto-load on|off" command has been renamed to
1845 "set auto-load-scripts on|off".
1847 * GDB has a new command: "set directories".
1848 It is like the "dir" command except that it replaces the
1849 source path list instead of augmenting it.
1851 * GDB now understands thread names.
1853 On GNU/Linux, "info threads" will display the thread name as set by
1854 prctl or pthread_setname_np.
1856 There is also a new command, "thread name", which can be used to
1857 assign a name internally for GDB to display.
1860 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1861 has been integrated into GDB.
1865 ** The function gdb.Write now accepts an optional keyword 'stream'.
1866 This keyword, when provided, will direct the output to either
1867 stdout, stderr, or GDB's logging output.
1869 ** Parameters can now be be sub-classed in Python, and in particular
1870 you may implement the get_set_doc and get_show_doc functions.
1871 This improves how Parameter set/show documentation is processed
1872 and allows for more dynamic content.
1874 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1875 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1876 have an is_valid method.
1878 ** Breakpoints can now be sub-classed in Python, and in particular
1879 you may implement a 'stop' function that is executed each time
1880 the inferior reaches that breakpoint.
1882 ** New function gdb.lookup_global_symbol looks up a global symbol.
1884 ** GDB values in Python are now callable if the value represents a
1885 function. For example, if 'some_value' represents a function that
1886 takes two integer parameters and returns a value, you can call
1887 that function like so:
1889 result = some_value (10,20)
1891 ** Module gdb.types has been added.
1892 It contains a collection of utilities for working with gdb.Types objects:
1893 get_basic_type, has_field, make_enum_dict.
1895 ** Module gdb.printing has been added.
1896 It contains utilities for writing and registering pretty-printers.
1897 New classes: PrettyPrinter, SubPrettyPrinter,
1898 RegexpCollectionPrettyPrinter.
1899 New function: register_pretty_printer.
1901 ** New commands "info pretty-printers", "enable pretty-printer" and
1902 "disable pretty-printer" have been added.
1904 ** gdb.parameter("directories") is now available.
1906 ** New function gdb.newest_frame returns the newest frame in the
1909 ** The gdb.InferiorThread class has a new "name" attribute. This
1910 holds the thread's name.
1912 ** Python Support for Inferior events.
1913 Python scripts can add observers to be notified of events
1914 occurring in the process being debugged.
1915 The following events are currently supported:
1916 - gdb.events.cont Continue event.
1917 - gdb.events.exited Inferior exited event.
1918 - gdb.events.stop Signal received, and Breakpoint hit events.
1922 ** GDB now puts template parameters in scope when debugging in an
1923 instantiation. For example, if you have:
1925 template<int X> int func (void) { return X; }
1927 then if you step into func<5>, "print X" will show "5". This
1928 feature requires proper debuginfo support from the compiler; it
1929 was added to GCC 4.5.
1931 ** The motion commands "next", "finish", "until", and "advance" now
1932 work better when exceptions are thrown. In particular, GDB will
1933 no longer lose control of the inferior; instead, the GDB will
1934 stop the inferior at the point at which the exception is caught.
1935 This functionality requires a change in the exception handling
1936 code that was introduced in GCC 4.5.
1938 * GDB now follows GCC's rules on accessing volatile objects when
1939 reading or writing target state during expression evaluation.
1940 One notable difference to prior behavior is that "print x = 0"
1941 no longer generates a read of x; the value of the assignment is
1942 now always taken directly from the value being assigned.
1944 * GDB now has some support for using labels in the program's source in
1945 linespecs. For instance, you can use "advance label" to continue
1946 execution to a label.
1948 * GDB now has support for reading and writing a new .gdb_index
1949 section. This section holds a fast index of DWARF debugging
1950 information and can be used to greatly speed up GDB startup and
1951 operation. See the documentation for `save gdb-index' for details.
1953 * The "watch" command now accepts an optional "-location" argument.
1954 When used, this causes GDB to watch the memory referred to by the
1955 expression. Such a watchpoint is never deleted due to it going out
1958 * GDB now supports thread debugging of core dumps on GNU/Linux.
1960 GDB now activates thread debugging using the libthread_db library
1961 when debugging GNU/Linux core dumps, similarly to when debugging
1962 live processes. As a result, when debugging a core dump file, GDB
1963 is now able to display pthread_t ids of threads. For example, "info
1964 threads" shows the same output as when debugging the process when it
1965 was live. In earlier releases, you'd see something like this:
1968 * 1 LWP 6780 main () at main.c:10
1970 While now you see this:
1973 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1975 It is also now possible to inspect TLS variables when debugging core
1978 When debugging a core dump generated on a machine other than the one
1979 used to run GDB, you may need to point GDB at the correct
1980 libthread_db library with the "set libthread-db-search-path"
1981 command. See the user manual for more details on this command.
1983 * When natively debugging programs on PowerPC BookE processors running
1984 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1985 which stop execution of the inferior whenever it executes an instruction
1986 at any address within the specified range. See the "PowerPC Embedded"
1987 section in the user manual for more details.
1989 * New features in the GDB remote stub, GDBserver
1991 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1992 and i686 LynxOS (version 5.x).
1994 ** GDBserver is now supported on Blackfin Linux.
1996 * New native configurations
1998 ia64 HP-UX ia64-*-hpux*
2002 Analog Devices, Inc. Blackfin Processor bfin-*
2004 * Ada task switching is now supported on sparc-elf targets when
2005 debugging a program using the Ravenscar Profile. For more information,
2006 see the "Tasking Support when using the Ravenscar Profile" section
2007 in the GDB user manual.
2009 * Guile support was removed.
2011 * New features in the GNU simulator
2013 ** The --map-info flag lists all known core mappings.
2015 ** CFI flashes may be simulated via the "cfi" device.
2017 *** Changes in GDB 7.2
2019 * Shared library support for remote targets by default
2021 When GDB is configured for a generic, non-OS specific target, like
2022 for example, --target=arm-eabi or one of the many *-*-elf targets,
2023 GDB now queries remote stubs for loaded shared libraries using the
2024 `qXfer:libraries:read' packet. Previously, shared library support
2025 was always disabled for such configurations.
2029 ** Argument Dependent Lookup (ADL)
2031 In C++ ADL lookup directs function search to the namespaces of its
2032 arguments even if the namespace has not been imported.
2042 Here the compiler will search for `foo' in the namespace of 'b'
2043 and find A::foo. GDB now supports this. This construct is commonly
2044 used in the Standard Template Library for operators.
2046 ** Improved User Defined Operator Support
2048 In addition to member operators, GDB now supports lookup of operators
2049 defined in a namespace and imported with a `using' directive, operators
2050 defined in the global scope, operators imported implicitly from an
2051 anonymous namespace, and the ADL operators mentioned in the previous
2053 GDB now also supports proper overload resolution for all the previously
2054 mentioned flavors of operators.
2056 ** static const class members
2058 Printing of static const class members that are initialized in the
2059 class definition has been fixed.
2061 * Windows Thread Information Block access.
2063 On Windows targets, GDB now supports displaying the Windows Thread
2064 Information Block (TIB) structure. This structure is visible either
2065 by using the new command `info w32 thread-information-block' or, by
2066 dereferencing the new convenience variable named `$_tlb', a
2067 thread-specific pointer to the TIB. This feature is also supported
2068 when remote debugging using GDBserver.
2070 * Static tracepoints
2072 Static tracepoints are calls in the user program into a tracing
2073 library. One such library is a port of the LTTng kernel tracer to
2074 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2075 When debugging with GDBserver, GDB now supports combining the GDB
2076 tracepoint machinery with such libraries. For example: the user can
2077 use GDB to probe a static tracepoint marker (a call from the user
2078 program into the tracing library) with the new "strace" command (see
2079 "New commands" below). This creates a "static tracepoint" in the
2080 breakpoint list, that can be manipulated with the same feature set
2081 as fast and regular tracepoints. E.g., collect registers, local and
2082 global variables, collect trace state variables, and define
2083 tracepoint conditions. In addition, the user can collect extra
2084 static tracepoint marker specific data, by collecting the new
2085 $_sdata internal variable. When analyzing the trace buffer, you can
2086 inspect $_sdata like any other variable available to GDB. For more
2087 information, see the "Tracepoints" chapter in GDB user manual. New
2088 remote packets have been defined to support static tracepoints, see
2089 the "New remote packets" section below.
2091 * Better reconstruction of tracepoints after disconnected tracing
2093 GDB will attempt to download the original source form of tracepoint
2094 definitions when starting a trace run, and then will upload these
2095 upon reconnection to the target, resulting in a more accurate
2096 reconstruction of the tracepoints that are in use on the target.
2100 You can now exercise direct control over the ways that GDB can
2101 affect your program. For instance, you can disallow the setting of
2102 breakpoints, so that the program can run continuously (assuming
2103 non-stop mode). In addition, the "observer" variable is available
2104 to switch all of the different controls; in observer mode, GDB
2105 cannot affect the target's behavior at all, which is useful for
2106 tasks like diagnosing live systems in the field.
2108 * The new convenience variable $_thread holds the number of the
2111 * New remote packets
2115 Return the address of the Windows Thread Information Block of a given thread.
2119 In response to several of the tracepoint packets, the target may now
2120 also respond with a number of intermediate `qRelocInsn' request
2121 packets before the final result packet, to have GDB handle
2122 relocating an instruction to execute at a different address. This
2123 is particularly useful for stubs that support fast tracepoints. GDB
2124 reports support for this feature in the qSupported packet.
2128 List static tracepoint markers in the target program.
2132 List static tracepoint markers at a given address in the target
2135 qXfer:statictrace:read
2137 Read the static trace data collected (by a `collect $_sdata'
2138 tracepoint action). The remote stub reports support for this packet
2139 to gdb's qSupported query.
2143 Send the current settings of GDB's permission flags.
2147 Send part of the source (textual) form of a tracepoint definition,
2148 which includes location, conditional, and action list.
2150 * The source command now accepts a -s option to force searching for the
2151 script in the source search path even if the script name specifies
2154 * New features in the GDB remote stub, GDBserver
2156 - GDBserver now support tracepoints (including fast tracepoints, and
2157 static tracepoints). The feature is currently supported by the
2158 i386-linux and amd64-linux builds. See the "Tracepoints support
2159 in gdbserver" section in the manual for more information.
2161 GDBserver JIT compiles the tracepoint's conditional agent
2162 expression bytecode into native code whenever possible for low
2163 overhead dynamic tracepoints conditionals. For such tracepoints,
2164 an expression that examines program state is evaluated when the
2165 tracepoint is reached, in order to determine whether to capture
2166 trace data. If the condition is simple and false, processing the
2167 tracepoint finishes very quickly and no data is gathered.
2169 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2170 for static tracepoints support.
2172 - GDBserver now supports x86_64 Windows 64-bit debugging.
2174 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2175 it understands register description.
2177 * The --batch flag now disables pagination and queries.
2179 * X86 general purpose registers
2181 GDB now supports reading/writing byte, word and double-word x86
2182 general purpose registers directly. This means you can use, say,
2183 $ah or $ax to refer, respectively, to the byte register AH and
2184 16-bit word register AX that are actually portions of the 32-bit
2185 register EAX or 64-bit register RAX.
2187 * The `commands' command now accepts a range of breakpoints to modify.
2188 A plain `commands' following a command that creates multiple
2189 breakpoints affects all the breakpoints set by that command. This
2190 applies to breakpoints set by `rbreak', and also applies when a
2191 single `break' command creates multiple breakpoints (e.g.,
2192 breakpoints on overloaded c++ functions).
2194 * The `rbreak' command now accepts a filename specification as part of
2195 its argument, limiting the functions selected by the regex to those
2196 in the specified file.
2198 * Support for remote debugging Windows and SymbianOS shared libraries
2199 from Unix hosts has been improved. Non Windows GDB builds now can
2200 understand target reported file names that follow MS-DOS based file
2201 system semantics, such as file names that include drive letters and
2202 use the backslash character as directory separator. This makes it
2203 possible to transparently use the "set sysroot" and "set
2204 solib-search-path" on Unix hosts to point as host copies of the
2205 target's shared libraries. See the new command "set
2206 target-file-system-kind" described below, and the "Commands to
2207 specify files" section in the user manual for more information.
2211 eval template, expressions...
2212 Convert the values of one or more expressions under the control
2213 of the string template to a command line, and call it.
2215 set target-file-system-kind unix|dos-based|auto
2216 show target-file-system-kind
2217 Set or show the assumed file system kind for target reported file
2220 save breakpoints <filename>
2221 Save all current breakpoint definitions to a file suitable for use
2222 in a later debugging session. To read the saved breakpoint
2223 definitions, use the `source' command.
2225 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2228 info static-tracepoint-markers
2229 Display information about static tracepoint markers in the target.
2231 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2232 Define a static tracepoint by probing a marker at the given
2233 function, line, address, or marker ID.
2237 Enable and disable observer mode.
2239 set may-write-registers on|off
2240 set may-write-memory on|off
2241 set may-insert-breakpoints on|off
2242 set may-insert-tracepoints on|off
2243 set may-insert-fast-tracepoints on|off
2244 set may-interrupt on|off
2245 Set individual permissions for GDB effects on the target. Note that
2246 some of these settings can have undesirable or surprising
2247 consequences, particularly when changed in the middle of a session.
2248 For instance, disabling the writing of memory can prevent
2249 breakpoints from being inserted, cause single-stepping to fail, or
2250 even crash your program, if you disable after breakpoints have been
2251 inserted. However, GDB should not crash.
2253 set record memory-query on|off
2254 show record memory-query
2255 Control whether to stop the inferior if memory changes caused
2256 by an instruction cannot be recorded.
2261 The disassemble command now supports "start,+length" form of two arguments.
2265 ** GDB now provides a new directory location, called the python directory,
2266 where Python scripts written for GDB can be installed. The location
2267 of that directory is <data-directory>/python, where <data-directory>
2268 is the GDB data directory. For more details, see section `Scripting
2269 GDB using Python' in the manual.
2271 ** The GDB Python API now has access to breakpoints, symbols, symbol
2272 tables, program spaces, inferiors, threads and frame's code blocks.
2273 Additionally, GDB Parameters can now be created from the API, and
2274 manipulated via set/show in the CLI.
2276 ** New functions gdb.target_charset, gdb.target_wide_charset,
2277 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2279 ** New exception gdb.GdbError.
2281 ** Pretty-printers are now also looked up in the current program space.
2283 ** Pretty-printers can now be individually enabled and disabled.
2285 ** GDB now looks for names of Python scripts to auto-load in a
2286 special section named `.debug_gdb_scripts', in addition to looking
2287 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2289 * Tracepoint actions were unified with breakpoint commands. In particular,
2290 there are no longer differences in "info break" output for breakpoints and
2291 tracepoints and the "commands" command can be used for both tracepoints and
2292 regular breakpoints.
2296 ARM Symbian arm*-*-symbianelf*
2298 * D language support.
2299 GDB now supports debugging programs written in the D programming
2302 * GDB now supports the extended ptrace interface for PowerPC which is
2303 available since Linux kernel version 2.6.34. This automatically enables
2304 any hardware breakpoints and additional hardware watchpoints available in
2305 the processor. The old ptrace interface exposes just one hardware
2306 watchpoint and no hardware breakpoints.
2308 * GDB is now able to use the Data Value Compare (DVC) register available on
2309 embedded PowerPC processors to implement in hardware simple watchpoint
2310 conditions of the form:
2312 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2314 This works in native GDB running on Linux kernels with the extended ptrace
2315 interface mentioned above.
2317 *** Changes in GDB 7.1
2321 ** Namespace Support
2323 GDB now supports importing of namespaces in C++. This enables the
2324 user to inspect variables from imported namespaces. Support for
2325 namepace aliasing has also been added. So, if a namespace is
2326 aliased in the current scope (e.g. namepace C=A; ) the user can
2327 print variables using the alias (e.g. (gdb) print C::x).
2331 All known bugs relating to the printing of virtual base class were
2332 fixed. It is now possible to call overloaded static methods using a
2337 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2338 and reinterpret_cast<> are now handled by the C++ expression parser.
2342 Xilinx MicroBlaze microblaze-*-*
2347 Xilinx MicroBlaze microblaze
2350 * Multi-program debugging.
2352 GDB now has support for multi-program (a.k.a. multi-executable or
2353 multi-exec) debugging. This allows for debugging multiple inferiors
2354 simultaneously each running a different program under the same GDB
2355 session. See "Debugging Multiple Inferiors and Programs" in the
2356 manual for more information. This implied some user visible changes
2357 in the multi-inferior support. For example, "info inferiors" now
2358 lists inferiors that are not running yet or that have exited
2359 already. See also "New commands" and "New options" below.
2361 * New tracing features
2363 GDB's tracepoint facility now includes several new features:
2365 ** Trace state variables
2367 GDB tracepoints now include support for trace state variables, which
2368 are variables managed by the target agent during a tracing
2369 experiment. They are useful for tracepoints that trigger each
2370 other, so for instance one tracepoint can count hits in a variable,
2371 and then a second tracepoint has a condition that is true when the
2372 count reaches a particular value. Trace state variables share the
2373 $-syntax of GDB convenience variables, and can appear in both
2374 tracepoint actions and condition expressions. Use the "tvariable"
2375 command to create, and "info tvariables" to view; see "Trace State
2376 Variables" in the manual for more detail.
2380 GDB now includes an option for defining fast tracepoints, which
2381 targets may implement more efficiently, such as by installing a jump
2382 into the target agent rather than a trap instruction. The resulting
2383 speedup can be by two orders of magnitude or more, although the
2384 tradeoff is that some program locations on some target architectures
2385 might not allow fast tracepoint installation, for instance if the
2386 instruction to be replaced is shorter than the jump. To request a
2387 fast tracepoint, use the "ftrace" command, with syntax identical to
2388 the regular trace command.
2390 ** Disconnected tracing
2392 It is now possible to detach GDB from the target while it is running
2393 a trace experiment, then reconnect later to see how the experiment
2394 is going. In addition, a new variable disconnected-tracing lets you
2395 tell the target agent whether to continue running a trace if the
2396 connection is lost unexpectedly.
2400 GDB now has the ability to save the trace buffer into a file, and
2401 then use that file as a target, similarly to you can do with
2402 corefiles. You can select trace frames, print data that was
2403 collected in them, and use tstatus to display the state of the
2404 tracing run at the moment that it was saved. To create a trace
2405 file, use "tsave <filename>", and to use it, do "target tfile
2408 ** Circular trace buffer
2410 You can ask the target agent to handle the trace buffer as a
2411 circular buffer, discarding the oldest trace frames to make room for
2412 newer ones, by setting circular-trace-buffer to on. This feature may
2413 not be available for all target agents.
2418 The disassemble command, when invoked with two arguments, now requires
2419 the arguments to be comma-separated.
2422 The info variables command now displays variable definitions. Files
2423 which only declare a variable are not shown.
2426 The source command is now capable of sourcing Python scripts.
2427 This feature is dependent on the debugger being build with Python
2430 Related to this enhancement is also the introduction of a new command
2431 "set script-extension" (see below).
2433 * New commands (for set/show, see "New options" below)
2435 record save [<FILENAME>]
2436 Save a file (in core file format) containing the process record
2437 execution log for replay debugging at a later time.
2439 record restore <FILENAME>
2440 Restore the process record execution log that was saved at an
2441 earlier time, for replay debugging.
2443 add-inferior [-copies <N>] [-exec <FILENAME>]
2446 clone-inferior [-copies <N>] [ID]
2447 Make a new inferior ready to execute the same program another
2448 inferior has loaded.
2453 maint info program-spaces
2454 List the program spaces loaded into GDB.
2456 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2457 show remote interrupt-sequence
2458 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2459 as the sequence to the remote target in order to interrupt the execution.
2460 Ctrl-C is a default. Some system prefers BREAK which is high level of
2461 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2462 Magic SysRq g. It is BREAK signal and character 'g'.
2464 set remote interrupt-on-connect [on | off]
2465 show remote interrupt-on-connect
2466 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2467 remote target when gdb connects to it. This is needed when you debug
2470 set remotebreak [on | off]
2472 Deprecated. Use "set/show remote interrupt-sequence" instead.
2474 tvariable $NAME [ = EXP ]
2475 Create or modify a trace state variable.
2478 List trace state variables and their values.
2480 delete tvariable $NAME ...
2481 Delete one or more trace state variables.
2484 Evaluate the given expressions without collecting anything into the
2485 trace buffer. (Valid in tracepoint actions only.)
2487 ftrace FN / FILE:LINE / *ADDR
2488 Define a fast tracepoint at the given function, line, or address.
2490 * New expression syntax
2492 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2493 GDB now parses 0b101010 identically with 42.
2497 set follow-exec-mode new|same
2498 show follow-exec-mode
2499 Control whether GDB reuses the same inferior across an exec call or
2500 creates a new one. This is useful to be able to restart the old
2501 executable after the inferior having done an exec call.
2503 set default-collect EXPR, ...
2504 show default-collect
2505 Define a list of expressions to be collected at each tracepoint.
2506 This is a useful way to ensure essential items are not overlooked,
2507 such as registers or a critical global variable.
2509 set disconnected-tracing
2510 show disconnected-tracing
2511 If set to 1, the target is instructed to continue tracing if it
2512 loses its connection to GDB. If 0, the target is to stop tracing
2515 set circular-trace-buffer
2516 show circular-trace-buffer
2517 If set to on, the target is instructed to use a circular trace buffer
2518 and discard the oldest trace frames instead of stopping the trace due
2519 to a full trace buffer. If set to off, the trace stops when the buffer
2520 fills up. Some targets may not support this.
2522 set script-extension off|soft|strict
2523 show script-extension
2524 If set to "off", the debugger does not perform any script language
2525 recognition, and all sourced files are assumed to be GDB scripts.
2526 If set to "soft" (the default), files are sourced according to
2527 filename extension, falling back to GDB scripts if the first
2529 If set to "strict", files are sourced according to filename extension.
2531 set ada trust-PAD-over-XVS on|off
2532 show ada trust-PAD-over-XVS
2533 If off, activate a workaround against a bug in the debugging information
2534 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2535 the GCC sources for more information about the GNAT encoding and
2536 PAD types in particular). It is always safe to set this option to
2537 off, but this introduces a slight performance penalty. The default
2540 * Python API Improvements
2542 ** GDB provides the new class gdb.LazyString. This is useful in
2543 some pretty-printing cases. The new method gdb.Value.lazy_string
2544 provides a simple way to create objects of this type.
2546 ** The fields returned by gdb.Type.fields now have an
2547 `is_base_class' attribute.
2549 ** The new method gdb.Type.range returns the range of an array type.
2551 ** The new method gdb.parse_and_eval can be used to parse and
2552 evaluate an expression.
2554 * New remote packets
2557 Define a trace state variable.
2560 Get the current value of a trace state variable.
2563 Set desired tracing behavior upon disconnection.
2566 Set the trace buffer to be linear or circular.
2569 Get data about the tracepoints currently in use.
2573 Process record now works correctly with hardware watchpoints.
2575 Multiple bug fixes have been made to the mips-irix port, making it
2576 much more reliable. In particular:
2577 - Debugging threaded applications is now possible again. Previously,
2578 GDB would hang while starting the program, or while waiting for
2579 the program to stop at a breakpoint.
2580 - Attaching to a running process no longer hangs.
2581 - An error occurring while loading a core file has been fixed.
2582 - Changing the value of the PC register now works again. This fixes
2583 problems observed when using the "jump" command, or when calling
2584 a function from GDB, or even when assigning a new value to $pc.
2585 - With the "finish" and "return" commands, the return value for functions
2586 returning a small array is now correctly printed.
2587 - It is now possible to break on shared library code which gets executed
2588 during a shared library init phase (code executed while executing
2589 their .init section). Previously, the breakpoint would have no effect.
2590 - GDB is now able to backtrace through the signal handler for
2591 non-threaded programs.
2593 PIE (Position Independent Executable) programs debugging is now supported.
2594 This includes debugging execution of PIC (Position Independent Code) shared
2595 libraries although for that, it should be possible to run such libraries as an
2598 *** Changes in GDB 7.0
2600 * GDB now has an interface for JIT compilation. Applications that
2601 dynamically generate code can create symbol files in memory and register
2602 them with GDB. For users, the feature should work transparently, and
2603 for JIT developers, the interface is documented in the GDB manual in the
2604 "JIT Compilation Interface" chapter.
2606 * Tracepoints may now be conditional. The syntax is as for
2607 breakpoints; either an "if" clause appended to the "trace" command,
2608 or the "condition" command is available. GDB sends the condition to
2609 the target for evaluation using the same bytecode format as is used
2610 for tracepoint actions.
2612 * The disassemble command now supports: an optional /r modifier, print the
2613 raw instructions in hex as well as in symbolic form, and an optional /m
2614 modifier to print mixed source+assembly.
2616 * Process record and replay
2618 In a architecture environment that supports ``process record and
2619 replay'', ``process record and replay'' target can record a log of
2620 the process execution, and replay it with both forward and reverse
2623 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2624 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2625 set execution-direction {forward|reverse}, for targets that support
2628 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2629 feature is available with a native GDB running on kernel version
2632 * GDB now has support for multi-byte and wide character sets on the
2633 target. Strings whose character type is wchar_t, char16_t, or
2634 char32_t are now correctly printed. GDB supports wide- and unicode-
2635 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2636 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2637 `printf'. This feature requires iconv to work properly; if your
2638 system does not have a working iconv, GDB can use GNU libiconv. See
2639 the installation instructions for more information.
2641 * GDB now supports automatic retrieval of shared library files from
2642 remote targets. To use this feature, specify a system root that begins
2643 with the `remote:' prefix, either via the `set sysroot' command or via
2644 the `--with-sysroot' configure-time option.
2646 * "info sharedlibrary" now takes an optional regex of libraries to show,
2647 and it now reports if a shared library has no debugging information.
2649 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2650 now complete on file names.
2652 * When completing in expressions, gdb will attempt to limit
2653 completions to allowable structure or union fields, where appropriate.
2654 For instance, consider:
2656 # struct example { int f1; double f2; };
2657 # struct example variable;
2660 If the user types TAB at the end of this command line, the available
2661 completions will be "f1" and "f2".
2663 * Inlined functions are now supported. They show up in backtraces, and
2664 the "step", "next", and "finish" commands handle them automatically.
2666 * GDB now supports the token-splicing (##) and stringification (#)
2667 operators when expanding macros. It also supports variable-arity
2670 * GDB now supports inspecting extra signal information, exported by
2671 the new $_siginfo convenience variable. The feature is currently
2672 implemented on linux ARM, i386 and amd64.
2674 * GDB can now display the VFP floating point registers and NEON vector
2675 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2676 can provide these registers (requires Linux 2.6.30 or later). Remote
2677 and simulator targets may also provide them.
2679 * New remote packets
2682 Search memory for a sequence of bytes.
2685 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2686 operation over reliable transport links. Use of this packet is
2687 controlled by the `set remote noack-packet' command.
2690 Kill the process with the specified process ID. Use this in preference
2691 to `k' when multiprocess protocol extensions are supported.
2694 Obtains additional operating system information
2698 Read or write additional signal information.
2700 * Removed remote protocol undocumented extension
2702 An undocumented extension to the remote protocol's `S' stop reply
2703 packet that permited the stub to pass a process id was removed.
2704 Remote servers should use the `T' stop reply packet instead.
2706 * GDB now supports multiple function calling conventions according to the
2707 DWARF-2 DW_AT_calling_convention function attribute.
2709 * The SH target utilizes the aforementioned change to distinguish between gcc
2710 and Renesas calling convention. It also adds the new CLI commands
2711 `set/show sh calling-convention'.
2713 * GDB can now read compressed debug sections, as produced by GNU gold
2714 with the --compress-debug-sections=zlib flag.
2716 * 64-bit core files are now supported on AIX.
2718 * Thread switching is now supported on Tru64.
2720 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2721 which will be allocated using malloc later in program execution.
2723 * The qXfer:libraries:read remote procotol packet now allows passing a
2724 list of section offsets.
2726 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2727 conditions handling signals delivered during attach or thread creation
2728 have also been fixed.
2730 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2731 From the user's standpoint, all unqualified instances of True and False
2732 are treated as the standard definitions, regardless of context.
2734 * GDB now parses C++ symbol and type names more flexibly. For
2737 template<typename T> class C { };
2740 GDB will now correctly handle all of:
2742 ptype C<char const *>
2743 ptype C<char const*>
2744 ptype C<const char *>
2745 ptype C<const char*>
2747 * New features in the GDB remote stub, gdbserver
2749 - The "--wrapper" command-line argument tells gdbserver to use a
2750 wrapper program to launch programs for debugging.
2752 - On PowerPC and S/390 targets, it is now possible to use a single
2753 gdbserver executable to debug both 32-bit and 64-bit programs.
2754 (This requires gdbserver itself to be built as a 64-bit executable.)
2756 - gdbserver uses the new noack protocol mode for TCP connections to
2757 reduce communications latency, if also supported and enabled in GDB.
2759 - Support for the sparc64-linux-gnu target is now included in
2762 - The amd64-linux build of gdbserver now supports debugging both
2763 32-bit and 64-bit programs.
2765 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2766 now support hardware watchpoints, and will use them automatically
2771 GDB now has support for scripting using Python. Whether this is
2772 available is determined at configure time.
2774 New GDB commands can now be written in Python.
2776 * Ada tasking support
2778 Ada tasks can now be inspected in GDB. The following commands have
2782 Print the list of Ada tasks.
2784 Print detailed information about task number N.
2786 Print the task number of the current task.
2788 Switch the context of debugging to task number N.
2790 * Support for user-defined prefixed commands. The "define" command can
2791 add new commands to existing prefixes, e.g. "target".
2793 * Multi-inferior, multi-process debugging.
2795 GDB now has generalized support for multi-inferior debugging. See
2796 "Debugging Multiple Inferiors" in the manual for more information.
2797 Although availability still depends on target support, the command
2798 set is more uniform now. The GNU/Linux specific multi-forks support
2799 has been migrated to this new framework. This implied some user
2800 visible changes; see "New commands" and also "Removed commands"
2803 * Target descriptions can now describe the target OS ABI. See the
2804 "Target Description Format" section in the user manual for more
2807 * Target descriptions can now describe "compatible" architectures
2808 to indicate that the target can execute applications for a different
2809 architecture in addition to those for the main target architecture.
2810 See the "Target Description Format" section in the user manual for
2813 * Multi-architecture debugging.
2815 GDB now includes general supports for debugging applications on
2816 hybrid systems that use more than one single processor architecture
2817 at the same time. Each such hybrid architecture still requires
2818 specific support to be added. The only hybrid architecture supported
2819 in this version of GDB is the Cell Broadband Engine.
2821 * GDB now supports integrated debugging of Cell/B.E. applications that
2822 use both the PPU and SPU architectures. To enable support for hybrid
2823 Cell/B.E. debugging, you need to configure GDB to support both the
2824 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2825 --enable-targets configure option.
2827 * Non-stop mode debugging.
2829 For some targets, GDB now supports an optional mode of operation in
2830 which you can examine stopped threads while other threads continue
2831 to execute freely. This is referred to as non-stop mode, with the
2832 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2833 section in the user manual for more information.
2835 To be able to support remote non-stop debugging, a remote stub needs
2836 to implement the non-stop mode remote protocol extensions, as
2837 described in the "Remote Non-Stop" section of the user manual. The
2838 GDB remote stub, gdbserver, has been adjusted to support these
2839 extensions on linux targets.
2841 * New commands (for set/show, see "New options" below)
2843 catch syscall [NAME(S) | NUMBER(S)]
2844 Catch system calls. Arguments, which should be names of system
2845 calls or their numbers, mean catch only those syscalls. Without
2846 arguments, every syscall will be caught. When the inferior issues
2847 any of the specified syscalls, GDB will stop and announce the system
2848 call, both when it is called and when its call returns. This
2849 feature is currently available with a native GDB running on the
2850 Linux Kernel, under the following architectures: x86, x86_64,
2851 PowerPC and PowerPC64.
2853 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2855 Search memory for a sequence of bytes.
2857 maint set python print-stack
2858 maint show python print-stack
2859 Show a stack trace when an error is encountered in a Python script.
2862 Invoke CODE by passing it to the Python interpreter.
2867 These allow macros to be defined, undefined, and listed
2871 Show operating system information about processes.
2874 List the inferiors currently under GDB's control.
2877 Switch focus to inferior number NUM.
2880 Detach from inferior number NUM.
2883 Kill inferior number NUM.
2887 set spu stop-on-load
2888 show spu stop-on-load
2889 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2891 set spu auto-flush-cache
2892 show spu auto-flush-cache
2893 Control whether to automatically flush the software-managed cache
2894 during Cell/B.E. debugging.
2896 set sh calling-convention
2897 show sh calling-convention
2898 Control the calling convention used when calling SH target functions.
2901 show debug timestamp
2902 Control display of timestamps with GDB debugging output.
2904 set disassemble-next-line
2905 show disassemble-next-line
2906 Control display of disassembled source lines or instructions when
2909 set remote noack-packet
2910 show remote noack-packet
2911 Set/show the use of remote protocol QStartNoAckMode packet. See above
2912 under "New remote packets."
2914 set remote query-attached-packet
2915 show remote query-attached-packet
2916 Control use of remote protocol `qAttached' (query-attached) packet.
2918 set remote read-siginfo-object
2919 show remote read-siginfo-object
2920 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2923 set remote write-siginfo-object
2924 show remote write-siginfo-object
2925 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2928 set remote reverse-continue
2929 show remote reverse-continue
2930 Control use of remote protocol 'bc' (reverse-continue) packet.
2932 set remote reverse-step
2933 show remote reverse-step
2934 Control use of remote protocol 'bs' (reverse-step) packet.
2936 set displaced-stepping
2937 show displaced-stepping
2938 Control displaced stepping mode. Displaced stepping is a way to
2939 single-step over breakpoints without removing them from the debuggee.
2940 Also known as "out-of-line single-stepping".
2943 show debug displaced
2944 Control display of debugging info for displaced stepping.
2946 maint set internal-error
2947 maint show internal-error
2948 Control what GDB does when an internal error is detected.
2950 maint set internal-warning
2951 maint show internal-warning
2952 Control what GDB does when an internal warning is detected.
2957 Use a wrapper program to launch programs for debugging.
2959 set multiple-symbols (all|ask|cancel)
2960 show multiple-symbols
2961 The value of this variable can be changed to adjust the debugger behavior
2962 when an expression or a breakpoint location contains an ambiguous symbol
2963 name (an overloaded function name, for instance).
2965 set breakpoint always-inserted
2966 show breakpoint always-inserted
2967 Keep breakpoints always inserted in the target, as opposed to inserting
2968 them when resuming the target, and removing them when the target stops.
2969 This option can improve debugger performance on slow remote targets.
2971 set arm fallback-mode (arm|thumb|auto)
2972 show arm fallback-mode
2973 set arm force-mode (arm|thumb|auto)
2975 These commands control how ARM GDB determines whether instructions
2976 are ARM or Thumb. The default for both settings is auto, which uses
2977 the current CPSR value for instructions without symbols; previous
2978 versions of GDB behaved as if "set arm fallback-mode arm".
2980 set disable-randomization
2981 show disable-randomization
2982 Standalone programs run with the virtual address space randomization enabled
2983 by default on some platforms. This option keeps the addresses stable across
2984 multiple debugging sessions.
2988 Control whether other threads are stopped or not when some thread hits
2993 Requests that asynchronous execution is enabled in the target, if available.
2994 In this case, it's possible to resume target in the background, and interact
2995 with GDB while the target is running. "show target-async" displays the
2996 current state of asynchronous execution of the target.
2998 set target-wide-charset
2999 show target-wide-charset
3000 The target-wide-charset is the name of the character set that GDB
3001 uses when printing characters whose type is wchar_t.
3003 set tcp auto-retry (on|off)
3005 set tcp connect-timeout
3006 show tcp connect-timeout
3007 These commands allow GDB to retry failed TCP connections to a remote stub
3008 with a specified timeout period; this is useful if the stub is launched
3009 in parallel with GDB but may not be ready to accept connections immediately.
3011 set libthread-db-search-path
3012 show libthread-db-search-path
3013 Control list of directories which GDB will search for appropriate
3016 set schedule-multiple (on|off)
3017 show schedule-multiple
3018 Allow GDB to resume all threads of all processes or only threads of
3019 the current process.
3023 Use more aggressive caching for accesses to the stack. This improves
3024 performance of remote debugging (particularly backtraces) without
3025 affecting correctness.
3027 set interactive-mode (on|off|auto)
3028 show interactive-mode
3029 Control whether GDB runs in interactive mode (on) or not (off).
3030 When in interactive mode, GDB waits for the user to answer all
3031 queries. Otherwise, GDB does not wait and assumes the default
3032 answer. When set to auto (the default), GDB determines which
3033 mode to use based on the stdin settings.
3038 For program forks, this is replaced by the new more generic `info
3039 inferiors' command. To list checkpoints, you can still use the
3040 `info checkpoints' command, which was an alias for the `info forks'
3044 Replaced by the new `inferior' command. To switch between
3045 checkpoints, you can still use the `restart' command, which was an
3046 alias for the `fork' command.
3049 This is removed, since some targets don't have a notion of
3050 processes. To switch between processes, you can still use the
3051 `inferior' command using GDB's own inferior number.
3054 For program forks, this is replaced by the new more generic `kill
3055 inferior' command. To delete a checkpoint, you can still use the
3056 `delete checkpoint' command, which was an alias for the `delete
3060 For program forks, this is replaced by the new more generic `detach
3061 inferior' command. To detach a checkpoint, you can still use the
3062 `detach checkpoint' command, which was an alias for the `detach
3065 * New native configurations
3067 x86/x86_64 Darwin i[34567]86-*-darwin*
3069 x86_64 MinGW x86_64-*-mingw*
3073 Lattice Mico32 lm32-*
3074 x86 DICOS i[34567]86-*-dicos*
3075 x86_64 DICOS x86_64-*-dicos*
3078 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3079 (mingw32ce) debugging.
3085 These commands were actually not implemented on any target.
3087 *** Changes in GDB 6.8
3089 * New native configurations
3091 NetBSD/hppa hppa*-*netbsd*
3092 Xtensa GNU/Linux xtensa*-*-linux*
3096 NetBSD/hppa hppa*-*-netbsd*
3097 Xtensa GNU/Lunux xtensa*-*-linux*
3099 * Change in command line behavior -- corefiles vs. process ids.
3101 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3102 attaching to process NUMBER fails, GDB no longer attempts to open a
3103 core file named NUMBER. Attaching to a program using the -c option
3104 is no longer supported. Instead, use the '-p' or '--pid' options.
3106 * GDB can now be built as a native debugger for debugging Windows x86
3107 (mingw32) Portable Executable (PE) programs.
3109 * Pending breakpoints no longer change their number when their address
3112 * GDB now supports breakpoints with multiple locations,
3113 including breakpoints on C++ constructors, inside C++ templates,
3114 and in inlined functions.
3116 * GDB's ability to debug optimized code has been improved. GDB more
3117 accurately identifies function bodies and lexical blocks that occupy
3118 more than one contiguous range of addresses.
3120 * Target descriptions can now describe registers for PowerPC.
3122 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3123 registers on PowerPC targets.
3125 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3126 targets even when the libthread_db library is not available.
3128 * The GDB remote stub, gdbserver, now supports the new file transfer
3129 commands (remote put, remote get, and remote delete).
3131 * The GDB remote stub, gdbserver, now supports run and attach in
3132 extended-remote mode.
3134 * hppa*64*-*-hpux11* target broken
3135 The debugger is unable to start a program and fails with the following
3136 error: "Error trying to get information about dynamic linker".
3137 The gdb-6.7 release is also affected.
3139 * GDB now supports the --enable-targets= configure option to allow
3140 building a single GDB executable that supports multiple remote
3141 target architectures.
3143 * GDB now supports debugging C and C++ programs which use the
3144 Decimal Floating Point extension. In addition, the PowerPC target
3145 now has a set of pseudo-registers to inspect decimal float values
3146 stored in two consecutive float registers.
3148 * The -break-insert MI command can optionally create pending
3151 * Improved support for debugging Ada
3152 Many improvements to the Ada language support have been made. These
3154 - Better support for Ada2005 interface types
3155 - Improved handling of arrays and slices in general
3156 - Better support for Taft-amendment types
3157 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3159 - Improved command completion in Ada
3162 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3167 set print frame-arguments (all|scalars|none)
3168 show print frame-arguments
3169 The value of this variable can be changed to control which argument
3170 values should be printed by the debugger when displaying a frame.
3175 Transfer files to and from a remote target, and delete remote files.
3182 Transfer files to and from a remote target, and delete remote files.
3184 * New remote packets
3191 Open, close, read, write, and delete files on the remote system.
3194 Attach to an existing process on the remote system, in extended-remote
3198 Run a new process on the remote system, in extended-remote mode.
3200 *** Changes in GDB 6.7
3202 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3203 bfd, libiberty and opcodes, as revealed by static analysis donated by
3204 Coverity, Inc. (http://scan.coverity.com).
3206 * When looking up multiply-defined global symbols, GDB will now prefer the
3207 symbol definition in the current shared library if it was built using the
3208 -Bsymbolic linker option.
3210 * When the Text User Interface (TUI) is not configured, GDB will now
3211 recognize the -tui command-line option and print a message that the TUI
3214 * The GDB remote stub, gdbserver, now has lower overhead for high
3215 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3217 * GDB for MIPS targets now autodetects whether a remote target provides
3218 32-bit or 64-bit register values.
3220 * Support for C++ member pointers has been improved.
3222 * GDB now understands XML target descriptions, which specify the
3223 target's overall architecture. GDB can read a description from
3224 a local file or over the remote serial protocol.
3226 * Vectors of single-byte data use a new integer type which is not
3227 automatically displayed as character or string data.
3229 * The /s format now works with the print command. It displays
3230 arrays of single-byte integers and pointers to single-byte integers
3233 * Target descriptions can now describe target-specific registers,
3234 for architectures which have implemented the support (currently
3235 only ARM, M68K, and MIPS).
3237 * GDB and the GDB remote stub, gdbserver, now support the XScale
3240 * The GDB remote stub, gdbserver, has been updated to support
3241 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3242 has been rewritten to use the standard GDB remote protocol.
3244 * GDB can now step into C++ functions which are called through thunks.
3246 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3248 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3249 layout. It also supports a TextSeg= and DataSeg= response when only
3250 segment base addresses (rather than offsets) are available.
3252 * The /i format now outputs any trailing branch delay slot instructions
3253 immediately following the last instruction within the count specified.
3255 * The GDB remote protocol "T" stop reply packet now supports a
3256 "library" response. Combined with the new "qXfer:libraries:read"
3257 packet, this response allows GDB to debug shared libraries on targets
3258 where the operating system manages the list of loaded libraries (e.g.
3259 Windows and SymbianOS).
3261 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3262 (DLLs) on Windows and Windows CE targets.
3264 * GDB now supports a faster verification that a .debug file matches its binary
3265 according to its build-id signature, if the signature is present.
3271 Enable or disable hardware flow control (RTS/CTS) on the serial port
3272 when debugging using remote targets.
3274 set mem inaccessible-by-default
3275 show mem inaccessible-by-default
3276 If the target supplies a memory map, for instance via the remote
3277 protocol's "qXfer:memory-map:read" packet, setting this variable
3278 prevents GDB from accessing memory outside the memory map. This
3279 is useful for targets with memory mapped registers or which react
3280 badly to accesses of unmapped address space.
3282 set breakpoint auto-hw
3283 show breakpoint auto-hw
3284 If the target supplies a memory map, for instance via the remote
3285 protocol's "qXfer:memory-map:read" packet, setting this variable
3286 lets GDB use hardware breakpoints automatically for memory regions
3287 where it can not use software breakpoints. This covers both the
3288 "break" command and internal breakpoints used for other commands
3289 including "next" and "finish".
3292 catch exception unhandled
3293 Stop the program execution when Ada exceptions are raised.
3296 Stop the program execution when an Ada assertion failed.
3300 Set an alternate system root for target files. This is a more
3301 general version of "set solib-absolute-prefix", which is now
3302 an alias to "set sysroot".
3305 Provide extended SPU facility status information. This set of
3306 commands is available only when debugging the Cell/B.E. SPU
3309 * New native configurations
3311 OpenBSD/sh sh*-*openbsd*
3314 unset tdesc filename
3316 Use the specified local file as an XML target description, and do
3317 not query the target for its built-in description.
3321 OpenBSD/sh sh*-*-openbsd*
3322 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3323 Toshiba Media Processor mep-elf
3325 * New remote packets
3328 Ignore the specified signals; pass them directly to the debugged program
3329 without stopping other threads or reporting them to GDB.
3331 qXfer:features:read:
3332 Read an XML target description from the target, which describes its
3337 Read or write contents of an spufs file on the target system. These
3338 packets are available only on the Cell/B.E. SPU architecture.
3340 qXfer:libraries:read:
3341 Report the loaded shared libraries. Combined with new "T" packet
3342 response, this packet allows GDB to debug shared libraries on
3343 targets where the operating system manages the list of loaded
3344 libraries (e.g. Windows and SymbianOS).
3348 Support for these obsolete configurations has been removed.
3356 i[34567]86-*-lynxos*
3357 i[34567]86-*-netware*
3358 i[34567]86-*-sco3.2v5*
3359 i[34567]86-*-sco3.2v4*
3361 i[34567]86-*-sysv4.2*
3364 i[34567]86-*-unixware2*
3365 i[34567]86-*-unixware*
3374 * Other removed features
3381 Various m68k-only ROM monitors.
3388 Various Renesas ROM monitors and debugging interfaces for SH and
3393 Support for a Macraigor serial interface to on-chip debugging.
3394 GDB does not directly support the newer parallel or USB
3399 A debug information format. The predecessor to DWARF 2 and
3400 DWARF 3, which are still supported.
3402 Support for the HP aCC compiler on HP-UX/PA-RISC
3404 SOM-encapsulated symbolic debugging information, automatic
3405 invocation of pxdb, and the aCC custom C++ ABI. This does not
3406 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3407 with aCC can still be debugged on an assembly level.
3409 MIPS ".pdr" sections
3411 A MIPS-specific format used to describe stack frame layout
3412 in debugging information.
3416 GDB could work with an older version of Guile to debug
3417 the interpreter and Scheme programs running in it.
3419 set mips stack-arg-size
3420 set mips saved-gpreg-size
3422 Use "set mips abi" to control parameter passing for MIPS.
3424 *** Changes in GDB 6.6
3429 Cell Broadband Engine SPU spu-elf
3431 * GDB can now be configured as a cross-debugger targeting native Windows
3432 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3433 running on a Windows system over TCP/IP to debug Windows programs.
3435 * The GDB remote stub, gdbserver, has been updated to support Windows and
3436 Cygwin debugging. Both single-threaded and multi-threaded programs are
3439 * The "set trust-readonly-sections" command works again. This command was
3440 broken in GDB 6.3, 6.4, and 6.5.
3442 * The "load" command now supports writing to flash memory, if the remote
3443 stub provides the required support.
3445 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3446 longer requires symbolic debug information (e.g. DWARF-2).
3451 unset substitute-path
3452 show substitute-path
3453 Manage a list of substitution rules that GDB uses to rewrite the name
3454 of the directories where the sources are located. This can be useful
3455 for instance when the sources were moved to a different location
3456 between compilation and debugging.
3460 Print each CLI command as it is executed. Each command is prefixed with
3461 a number of `+' symbols representing the nesting depth.
3462 The source command now has a `-v' option to enable the same feature.
3466 The ARM Demon monitor support (RDP protocol, "target rdp").
3468 Kernel Object Display, an embedded debugging feature which only worked with
3469 an obsolete version of Cisco IOS.
3471 The 'set download-write-size' and 'show download-write-size' commands.
3473 * New remote packets
3476 Tell a stub about GDB client features, and request remote target features.
3477 The first feature implemented is PacketSize, which allows the target to
3478 specify the size of packets it can handle - to minimize the number of
3479 packets required and improve performance when connected to a remote
3483 Fetch an OS auxilliary vector from the remote stub. This packet is a
3484 more efficient replacement for qPart:auxv:read.
3486 qXfer:memory-map:read:
3487 Fetch a memory map from the remote stub, including information about
3488 RAM, ROM, and flash memory devices.
3493 Erase and program a flash memory device.
3495 * Removed remote packets
3498 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3499 used it, and only gdbserver implemented it.
3501 *** Changes in GDB 6.5
3505 Renesas M32C/M16C m32c-elf
3507 Morpho Technologies ms1 ms1-elf
3511 init-if-undefined Initialize a convenience variable, but
3512 only if it doesn't already have a value.
3514 The following commands are presently only implemented for native GNU/Linux:
3516 checkpoint Save a snapshot of the program state.
3518 restart <n> Return the program state to a
3519 previously saved state.
3521 info checkpoints List currently saved checkpoints.
3523 delete-checkpoint <n> Delete a previously saved checkpoint.
3525 set|show detach-on-fork Tell gdb whether to detach from a newly
3526 forked process, or to keep debugging it.
3528 info forks List forks of the user program that
3529 are available to be debugged.
3531 fork <n> Switch to debugging one of several
3532 forks of the user program that are
3533 available to be debugged.
3535 delete-fork <n> Delete a fork from the list of forks
3536 that are available to be debugged (and
3537 kill the forked process).
3539 detach-fork <n> Delete a fork from the list of forks
3540 that are available to be debugged (and
3541 allow the process to continue).
3545 Morpho Technologies ms2 ms1-elf
3547 * Improved Windows host support
3549 GDB now builds as a cross debugger hosted on i686-mingw32, including
3550 native console support, and remote communications using either
3551 network sockets or serial ports.
3553 * Improved Modula-2 language support
3555 GDB can now print most types in the Modula-2 syntax. This includes:
3556 basic types, set types, record types, enumerated types, range types,
3557 pointer types and ARRAY types. Procedure var parameters are correctly
3558 printed and hexadecimal addresses and character constants are also
3559 written in the Modula-2 syntax. Best results can be obtained by using
3560 GNU Modula-2 together with the -gdwarf-2 command line option.
3564 The ARM rdi-share module.
3566 The Netware NLM debug server.
3568 *** Changes in GDB 6.4
3570 * New native configurations
3572 OpenBSD/arm arm*-*-openbsd*
3573 OpenBSD/mips64 mips64-*-openbsd*
3577 Morpho Technologies ms1 ms1-elf
3579 * New command line options
3581 --batch-silent As for --batch, but totally silent.
3582 --return-child-result The debugger will exist with the same value
3583 the child (debugged) program exited with.
3584 --eval-command COMMAND, -ex COMMAND
3585 Execute a single GDB CLI command. This may be
3586 specified multiple times and in conjunction
3587 with the --command (-x) option.
3589 * Deprecated commands removed
3591 The following commands, that were deprecated in 2000, have been
3595 set|show arm disassembly-flavor set|show arm disassembler
3596 othernames set arm disassembler
3597 set|show remotedebug set|show debug remote
3598 set|show archdebug set|show debug arch
3599 set|show eventdebug set|show debug event
3602 * New BSD user-level threads support
3604 It is now possible to debug programs using the user-level threads
3605 library on OpenBSD and FreeBSD. Currently supported (target)
3608 FreeBSD/amd64 x86_64-*-freebsd*
3609 FreeBSD/i386 i386-*-freebsd*
3610 OpenBSD/i386 i386-*-openbsd*
3612 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3613 are not yet supported.
3615 * New support for Matsushita MN10300 w/sim added
3616 (Work in progress). mn10300-elf.
3618 * REMOVED configurations and files
3620 VxWorks and the XDR protocol *-*-vxworks
3621 Motorola MCORE mcore-*-*
3622 National Semiconductor NS32000 ns32k-*-*
3624 * New "set print array-indexes" command
3626 After turning this setting "on", GDB prints the index of each element
3627 when displaying arrays. The default is "off" to preserve the previous
3630 * VAX floating point support
3632 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3634 * User-defined command support
3636 In addition to using $arg0..$arg9 for argument passing, it is now possible
3637 to use $argc to determine now many arguments have been passed. See the
3638 section on user-defined commands in the user manual for more information.
3640 *** Changes in GDB 6.3:
3642 * New command line option
3644 GDB now accepts -l followed by a number to set the timeout for remote
3647 * GDB works with GCC -feliminate-dwarf2-dups
3649 GDB now supports a more compact representation of DWARF-2 debug
3650 information using DW_FORM_ref_addr references. These are produced
3651 by GCC with the option -feliminate-dwarf2-dups and also by some
3652 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3653 to use -feliminate-dwarf2-dups.
3655 * Internationalization
3657 When supported by the host system, GDB will be built with
3658 internationalization (libintl). The task of marking up the sources is
3659 continued, we're looking forward to our first translation.
3663 Initial support for debugging programs compiled with the GNAT
3664 implementation of the Ada programming language has been integrated
3665 into GDB. In this release, support is limited to expression evaluation.
3667 * New native configurations
3669 GNU/Linux/m32r m32r-*-linux-gnu
3673 GDB's remote protocol now includes support for the 'p' packet. This
3674 packet is used to fetch individual registers from a remote inferior.
3676 * END-OF-LIFE registers[] compatibility module
3678 GDB's internal register infrastructure has been completely rewritten.
3679 The new infrastructure making possible the implementation of key new
3680 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3683 GDB 6.3 will be the last release to include the the registers[]
3684 compatibility module that allowed out-of-date configurations to
3685 continue to work. This change directly impacts the following
3695 powerpc bdm protocol
3697 Unless there is activity to revive these configurations, they will be
3698 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3700 * OBSOLETE configurations and files
3702 Configurations that have been declared obsolete in this release have
3703 been commented out. Unless there is activity to revive these
3704 configurations, the next release of GDB will have their sources
3705 permanently REMOVED.
3714 *** Changes in GDB 6.2.1:
3716 * MIPS `break main; run' gave an heuristic-fence-post warning
3718 When attempting to run even a simple program, a warning about
3719 heuristic-fence-post being hit would be reported. This problem has
3722 * MIPS IRIX 'long double' crashed GDB
3724 When examining a long double variable, GDB would get a segmentation
3725 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3726 IRIX long double values).
3730 A bug in the VAX stack code was causing problems with the "next"
3731 command. This problem has been fixed.
3733 *** Changes in GDB 6.2:
3735 * Fix for ``many threads''
3737 On GNU/Linux systems that use the NPTL threads library, a program
3738 rapidly creating and deleting threads would confuse GDB leading to the
3741 ptrace: No such process.
3742 thread_db_get_info: cannot get thread info: generic error
3744 This problem has been fixed.
3746 * "-async" and "-noasync" options removed.
3748 Support for the broken "-noasync" option has been removed (it caused
3751 * New ``start'' command.
3753 This command runs the program until the begining of the main procedure.
3755 * New BSD Kernel Data Access Library (libkvm) interface
3757 Using ``target kvm'' it is now possible to debug kernel core dumps and
3758 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3759 platforms. Currently supported (native-only) configurations are:
3761 FreeBSD/amd64 x86_64-*-freebsd*
3762 FreeBSD/i386 i?86-*-freebsd*
3763 NetBSD/i386 i?86-*-netbsd*
3764 NetBSD/m68k m68*-*-netbsd*
3765 NetBSD/sparc sparc-*-netbsd*
3766 OpenBSD/amd64 x86_64-*-openbsd*
3767 OpenBSD/i386 i?86-*-openbsd*
3768 OpenBSD/m68k m68*-openbsd*
3769 OpenBSD/sparc sparc-*-openbsd*
3771 * Signal trampoline code overhauled
3773 Many generic problems with GDB's signal handling code have been fixed.
3774 These include: backtraces through non-contiguous stacks; recognition
3775 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3776 call; backtrace through a signal trampoline; step into and out of
3777 signal handlers; and single-stepping in the signal trampoline.
3779 Please note that kernel bugs are a limiting factor here. These
3780 features have been shown to work on an s390 GNU/Linux system that
3781 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3783 * Cygwin support for DWARF 2 added.
3785 * New native configurations
3787 GNU/Linux/hppa hppa*-*-linux*
3788 OpenBSD/hppa hppa*-*-openbsd*
3789 OpenBSD/m68k m68*-*-openbsd*
3790 OpenBSD/m88k m88*-*-openbsd*
3791 OpenBSD/powerpc powerpc-*-openbsd*
3792 NetBSD/vax vax-*-netbsd*
3793 OpenBSD/vax vax-*-openbsd*
3795 * END-OF-LIFE frame compatibility module
3797 GDB's internal frame infrastructure has been completely rewritten.
3798 The new infrastructure making it possible to support key new features
3799 including DWARF 2 Call Frame Information. To aid in the task of
3800 migrating old configurations to this new infrastructure, a
3801 compatibility module, that allowed old configurations to continue to
3802 work, was also included.
3804 GDB 6.2 will be the last release to include this frame compatibility
3805 module. This change directly impacts the following configurations:
3815 Unless there is activity to revive these configurations, they will be
3816 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3818 * REMOVED configurations and files
3820 Sun 3, running SunOS 3 m68*-*-sunos3*
3821 Sun 3, running SunOS 4 m68*-*-sunos4*
3822 Sun 2, running SunOS 3 m68000-*-sunos3*
3823 Sun 2, running SunOS 4 m68000-*-sunos4*
3824 Motorola 680x0 running LynxOS m68*-*-lynxos*
3825 AT&T 3b1/Unix pc m68*-att-*
3826 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3827 decstation mips-dec-* mips-little-*
3828 riscos mips-*-riscos* mips-*-sysv*
3829 sonymips mips-sony-*
3830 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3832 *** Changes in GDB 6.1.1:
3834 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3836 The TUI (Text-mode User Interface) is now built as part of a default
3837 GDB configuration. It is enabled by either selecting the TUI with the
3838 command line option "-i=tui" or by running the separate "gdbtui"
3839 program. For more information on the TUI, see the manual "Debugging
3842 * Pending breakpoint support (also included in GDB 6.1)
3844 Support has been added to allow you to specify breakpoints in shared
3845 libraries that have not yet been loaded. If a breakpoint location
3846 cannot be found, and the "breakpoint pending" option is set to auto,
3847 GDB queries you if you wish to make the breakpoint pending on a future
3848 shared-library load. If and when GDB resolves the breakpoint symbol,
3849 the pending breakpoint is removed as one or more regular breakpoints
3852 Pending breakpoints are very useful for GCJ Java debugging.
3854 * Fixed ISO-C build problems
3856 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3857 non ISO-C code that stopped them being built using a more strict ISO-C
3858 compiler (e.g., IBM's C compiler).
3860 * Fixed build problem on IRIX 5
3862 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3863 wasn't able to compile compile on an IRIX 5 system.
3865 * Added execute permission to gdb/gdbserver/configure
3867 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3868 permission. This bug would cause configure to fail on a number of
3869 systems (Solaris, IRIX). Ref: server/519.
3871 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3873 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3874 has been updated to use constant array sizes.
3876 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3878 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3879 its generated DWARF Call Frame Info. This encoding was causing GDB to
3880 panic, that panic has been fixed. Ref: gdb/1628.
3882 * Fixed a problem when examining parameters in shared library code.
3884 When examining parameters in optimized shared library code generated
3885 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3886 not available''. GDB now correctly displays the variable's value.
3888 *** Changes in GDB 6.1:
3890 * Removed --with-mmalloc
3892 Support for the mmalloc memory manager has been removed, as it
3893 conflicted with the internal gdb byte cache.
3895 * Changes in AMD64 configurations
3897 The AMD64 target now includes the %cs and %ss registers. As a result
3898 the AMD64 remote protocol has changed; this affects the floating-point
3899 and SSE registers. If you rely on those registers for your debugging,
3900 you should upgrade gdbserver on the remote side.
3902 * Revised SPARC target
3904 The SPARC target has been completely revised, incorporating the
3905 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3906 support for LynxOS and SunOS 4 has been dropped. Calling functions
3907 from within GDB on operating systems with a non-executable stack
3908 (Solaris, OpenBSD) now works.
3912 GDB has a new C++ demangler which does a better job on the mangled
3913 names generated by current versions of g++. It also runs faster, so
3914 with this and other changes gdb should now start faster on large C++
3917 * DWARF 2 Location Expressions
3919 GDB support for location expressions has been extended to support function
3920 arguments and frame bases. Older versions of GDB could crash when they
3923 * C++ nested types and namespaces
3925 GDB's support for nested types and namespaces in C++ has been
3926 improved, especially if you use the DWARF 2 debugging format. (This
3927 is the default for recent versions of GCC on most platforms.)
3928 Specifically, if you have a class "Inner" defined within a class or
3929 namespace "Outer", then GDB realizes that the class's name is
3930 "Outer::Inner", not simply "Inner". This should greatly reduce the
3931 frequency of complaints about not finding RTTI symbols. In addition,
3932 if you are stopped at inside of a function defined within a namespace,
3933 GDB modifies its name lookup accordingly.
3935 * New native configurations
3937 NetBSD/amd64 x86_64-*-netbsd*
3938 OpenBSD/amd64 x86_64-*-openbsd*
3939 OpenBSD/alpha alpha*-*-openbsd*
3940 OpenBSD/sparc sparc-*-openbsd*
3941 OpenBSD/sparc64 sparc64-*-openbsd*
3943 * New debugging protocols
3945 M32R with SDI protocol m32r-*-elf*
3947 * "set prompt-escape-char" command deleted.
3949 The command "set prompt-escape-char" has been deleted. This command,
3950 and its very obscure effet on GDB's prompt, was never documented,
3951 tested, nor mentioned in the NEWS file.
3953 * OBSOLETE configurations and files
3955 Configurations that have been declared obsolete in this release have
3956 been commented out. Unless there is activity to revive these
3957 configurations, the next release of GDB will have their sources
3958 permanently REMOVED.
3960 Sun 3, running SunOS 3 m68*-*-sunos3*
3961 Sun 3, running SunOS 4 m68*-*-sunos4*
3962 Sun 2, running SunOS 3 m68000-*-sunos3*
3963 Sun 2, running SunOS 4 m68000-*-sunos4*
3964 Motorola 680x0 running LynxOS m68*-*-lynxos*
3965 AT&T 3b1/Unix pc m68*-att-*
3966 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3967 decstation mips-dec-* mips-little-*
3968 riscos mips-*-riscos* mips-*-sysv*
3969 sonymips mips-sony-*
3970 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3972 * REMOVED configurations and files
3974 SGI Irix-4.x mips-sgi-irix4 or iris4
3975 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3976 Z8000 simulator z8k-zilog-none or z8ksim
3977 Matsushita MN10200 w/simulator mn10200-*-*
3978 H8/500 simulator h8500-hitachi-hms or h8500hms
3979 HP/PA running BSD hppa*-*-bsd*
3980 HP/PA running OSF/1 hppa*-*-osf*
3981 HP/PA Pro target hppa*-*-pro*
3982 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3983 386BSD i[3456]86-*-bsd*
3984 Sequent family i[3456]86-sequent-sysv4*
3985 i[3456]86-sequent-sysv*
3986 i[3456]86-sequent-bsd*
3987 SPARC running LynxOS sparc-*-lynxos*
3988 SPARC running SunOS 4 sparc-*-sunos4*
3989 Tsqware Sparclet sparclet-*-*
3990 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3992 *** Changes in GDB 6.0:
3996 Support for debugging the Objective-C programming language has been
3997 integrated into GDB.
3999 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4001 DWARF 2's Call Frame Information makes available compiler generated
4002 information that more exactly describes the program's run-time stack.
4003 By using this information, GDB is able to provide more robust stack
4006 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4007 have been updated to use a new backtrace mechanism which includes
4008 DWARF 2 CFI support.
4012 GDB's remote protocol has been extended to include support for hosted
4013 file I/O (where the remote target uses GDB's file system). See GDB's
4014 remote protocol documentation for details.
4016 * All targets using the new architecture framework.
4018 All of GDB's targets have been updated to use the new internal
4019 architecture framework. The way is now open for future GDB releases
4020 to include cross-architecture native debugging support (i386 on amd64,
4023 * GNU/Linux's Thread Local Storage (TLS)
4025 GDB now includes support for for the GNU/Linux implementation of
4026 per-thread variables.
4028 * GNU/Linux's Native POSIX Thread Library (NPTL)
4030 GDB's thread code has been updated to work with either the new
4031 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4033 * Separate debug info.
4035 GDB, in conjunction with BINUTILS, now supports a mechanism for
4036 automatically loading debug information from a separate file. Instead
4037 of shipping full debug and non-debug versions of system libraries,
4038 system integrators can now instead ship just the stripped libraries
4039 and optional debug files.
4041 * DWARF 2 Location Expressions
4043 DWARF 2 Location Expressions allow the compiler to more completely
4044 describe the location of variables (even in optimized code) to the
4047 GDB now includes preliminary support for location expressions (support
4048 for DW_OP_piece is still missing).
4052 A number of long standing bugs that caused GDB to die while starting a
4053 Java application have been fixed. GDB's Java support is now
4054 considered "useable".
4056 * GNU/Linux support for fork, vfork, and exec.
4058 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4059 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4062 * GDB supports logging output to a file
4064 There are two new commands, "set logging" and "show logging", which can be
4065 used to capture GDB's output to a file.
4067 * The meaning of "detach" has changed for gdbserver
4069 The "detach" command will now resume the application, as documented. To
4070 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4073 * d10v, m68hc11 `regs' command deprecated
4075 The `info registers' command has been updated so that it displays the
4076 registers using a format identical to the old `regs' command.
4080 A new command, "maint set profile on/off", has been added. This command can
4081 be used to enable or disable profiling while running GDB, to profile a
4082 session or a set of commands. In addition there is a new configure switch,
4083 "--enable-profiling", which will cause GDB to be compiled with profiling
4084 data, for more informative profiling results.
4086 * Default MI syntax changed to "mi2".
4088 The default MI (machine interface) syntax, enabled by the command line
4089 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4090 "mi1", can be enabled by specifying the option "-i=mi1".
4092 Support for the original "mi0" syntax (included in GDB 5.0) has been
4095 Fix for gdb/192: removed extraneous space when displaying frame level.
4096 Fix for gdb/672: update changelist is now output in mi list format.
4097 Fix for gdb/702: a -var-assign that updates the value now shows up
4098 in a subsequent -var-update.
4100 * New native configurations.
4102 FreeBSD/amd64 x86_64-*-freebsd*
4104 * Multi-arched targets.
4106 HP/PA HPUX11 hppa*-*-hpux*
4107 Renesas M32R/D w/simulator m32r-*-elf*
4109 * OBSOLETE configurations and files
4111 Configurations that have been declared obsolete in this release have
4112 been commented out. Unless there is activity to revive these
4113 configurations, the next release of GDB will have their sources
4114 permanently REMOVED.
4116 Z8000 simulator z8k-zilog-none or z8ksim
4117 Matsushita MN10200 w/simulator mn10200-*-*
4118 H8/500 simulator h8500-hitachi-hms or h8500hms
4119 HP/PA running BSD hppa*-*-bsd*
4120 HP/PA running OSF/1 hppa*-*-osf*
4121 HP/PA Pro target hppa*-*-pro*
4122 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4123 Sequent family i[3456]86-sequent-sysv4*
4124 i[3456]86-sequent-sysv*
4125 i[3456]86-sequent-bsd*
4126 Tsqware Sparclet sparclet-*-*
4127 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4129 * REMOVED configurations and files
4132 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4133 IBM AIX PS/2 i[3456]86-*-aix
4134 i386 running Mach 3.0 i[3456]86-*-mach3*
4135 i386 running Mach i[3456]86-*-mach*
4136 i386 running OSF/1 i[3456]86-*osf1mk*
4137 HP/Apollo 68k Family m68*-apollo*-sysv*,
4139 m68*-hp-bsd*, m68*-hp-hpux*
4140 Argonaut Risc Chip (ARC) arc-*-*
4141 Mitsubishi D30V d30v-*-*
4142 Fujitsu FR30 fr30-*-elf*
4143 OS/9000 i[34]86-*-os9k
4144 I960 with MON960 i960-*-coff
4146 * MIPS $fp behavior changed
4148 The convenience variable $fp, for the MIPS, now consistently returns
4149 the address of the current frame's base. Previously, depending on the
4150 context, $fp could refer to either $sp or the current frame's base
4151 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4152 The GNU Source-Level Debugger''.
4154 *** Changes in GDB 5.3:
4156 * GNU/Linux shared library multi-threaded performance improved.
4158 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4159 `/proc', in preference to `ptrace' for memory reads. This may result
4160 in an improvement in the start-up time of multi-threaded, shared
4161 library applications when run under GDB. One GDB user writes: ``loads
4162 shared libs like mad''.
4164 * ``gdbserver'' now supports multi-threaded applications on some targets
4166 Support for debugging multi-threaded applications which use
4167 the GNU/Linux LinuxThreads package has been added for
4168 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4169 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4171 * GDB now supports C/C++ preprocessor macros.
4173 GDB now expands preprocessor macro invocations in C/C++ expressions,
4174 and provides various commands for showing macro definitions and how
4177 The new command `macro expand EXPRESSION' expands any macro
4178 invocations in expression, and shows the result.
4180 The new command `show macro MACRO-NAME' shows the definition of the
4181 macro named MACRO-NAME, and where it was defined.
4183 Most compilers don't include information about macros in the debugging
4184 information by default. In GCC 3.1, for example, you need to compile
4185 your program with the options `-gdwarf-2 -g3'. If the macro
4186 information is present in the executable, GDB will read it.
4188 * Multi-arched targets.
4190 DEC Alpha (partial) alpha*-*-*
4191 DEC VAX (partial) vax-*-*
4193 National Semiconductor NS32000 (partial) ns32k-*-*
4194 Motorola 68000 (partial) m68k-*-*
4195 Motorola MCORE mcore-*-*
4199 Fujitsu FRV architecture added by Red Hat frv*-*-*
4202 * New native configurations
4204 Alpha NetBSD alpha*-*-netbsd*
4205 SH NetBSD sh*-*-netbsdelf*
4206 MIPS NetBSD mips*-*-netbsd*
4207 UltraSPARC NetBSD sparc64-*-netbsd*
4209 * OBSOLETE configurations and files
4211 Configurations that have been declared obsolete in this release have
4212 been commented out. Unless there is activity to revive these
4213 configurations, the next release of GDB will have their sources
4214 permanently REMOVED.
4216 Mitsubishi D30V d30v-*-*
4217 OS/9000 i[34]86-*-os9k
4218 IBM AIX PS/2 i[3456]86-*-aix
4219 Fujitsu FR30 fr30-*-elf*
4220 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4221 Argonaut Risc Chip (ARC) arc-*-*
4222 i386 running Mach 3.0 i[3456]86-*-mach3*
4223 i386 running Mach i[3456]86-*-mach*
4224 i386 running OSF/1 i[3456]86-*osf1mk*
4225 HP/Apollo 68k Family m68*-apollo*-sysv*,
4227 m68*-hp-bsd*, m68*-hp-hpux*
4228 I960 with MON960 i960-*-coff
4230 * OBSOLETE languages
4232 CHILL, a Pascal like language used by telecommunications companies.
4234 * REMOVED configurations and files
4236 AMD 29k family via UDI a29k-amd-udi, udi29k
4237 A29K VxWorks a29k-*-vxworks
4238 AMD 29000 embedded, using EBMON a29k-none-none
4239 AMD 29000 embedded with COFF a29k-none-coff
4240 AMD 29000 embedded with a.out a29k-none-aout
4242 testsuite/gdb.hp/gdb.threads-hp/ directory
4244 * New command "set max-user-call-depth <nnn>"
4246 This command allows the user to limit the call depth of user-defined
4247 commands. The default is 1024.
4249 * Changes in FreeBSD/i386 native debugging.
4251 Support for the "generate-core-file" has been added.
4253 * New commands "dump", "append", and "restore".
4255 These commands allow data to be copied from target memory
4256 to a bfd-format or binary file (dump and append), and back
4257 from a file into memory (restore).
4259 * Improved "next/step" support on multi-processor Alpha Tru64.
4261 The previous single-step mechanism could cause unpredictable problems,
4262 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4263 of a software single-step mechanism prevents this.
4265 *** Changes in GDB 5.2.1:
4273 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4274 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4275 Fix, by Joel Brobecker imported from mainline.
4277 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4278 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4279 Fix, by Fred Fish, imported from mainline.
4281 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4282 Surprisingly enough, it works now.
4283 By Michal Ludvig, imported from mainline.
4285 i386 hardware watchpoint support:
4286 avoid misses on second run for some targets.
4287 By Pierre Muller, imported from mainline.
4289 *** Changes in GDB 5.2:
4291 * New command "set trust-readonly-sections on[off]".
4293 This command is a hint that tells gdb that read-only sections
4294 really are read-only (ie. that their contents will not change).
4295 In this mode, gdb will go to the object file rather than the
4296 target to read memory from read-only sections (such as ".text").
4297 This can be a significant performance improvement on some
4298 (notably embedded) targets.
4300 * New command "generate-core-file" (or "gcore").
4302 This new gdb command allows the user to drop a core file of the child
4303 process state at any time. So far it's been implemented only for
4304 GNU/Linux and Solaris, but should be relatively easily ported to other
4305 hosts. Argument is core file name (defaults to core.<pid>).
4307 * New command line option
4309 GDB now accepts --pid or -p followed by a process id.
4311 * Change in command line behavior -- corefiles vs. process ids.
4313 There is a subtle behavior in the way in which GDB handles
4314 command line arguments. The first non-flag argument is always
4315 a program to debug, but the second non-flag argument may either
4316 be a corefile or a process id. Previously, GDB would attempt to
4317 open the second argument as a corefile, and if that failed, would
4318 issue a superfluous error message and then attempt to attach it as
4319 a process. Now, if the second argument begins with a non-digit,
4320 it will be treated as a corefile. If it begins with a digit,
4321 GDB will attempt to attach it as a process, and if no such process
4322 is found, will then attempt to open it as a corefile.
4324 * Changes in ARM configurations.
4326 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4327 configuration is fully multi-arch.
4329 * New native configurations
4331 ARM NetBSD arm*-*-netbsd*
4332 x86 OpenBSD i[3456]86-*-openbsd*
4333 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4334 Sparc64 running FreeBSD sparc64-*-freebsd*
4338 Sanyo XStormy16 xstormy16-elf
4340 * OBSOLETE configurations and files
4342 Configurations that have been declared obsolete in this release have
4343 been commented out. Unless there is activity to revive these
4344 configurations, the next release of GDB will have their sources
4345 permanently REMOVED.
4347 AMD 29k family via UDI a29k-amd-udi, udi29k
4348 A29K VxWorks a29k-*-vxworks
4349 AMD 29000 embedded, using EBMON a29k-none-none
4350 AMD 29000 embedded with COFF a29k-none-coff
4351 AMD 29000 embedded with a.out a29k-none-aout
4353 testsuite/gdb.hp/gdb.threads-hp/ directory
4355 * REMOVED configurations and files
4357 TI TMS320C80 tic80-*-*
4359 PowerPC Solaris powerpcle-*-solaris*
4360 PowerPC Windows NT powerpcle-*-cygwin32
4361 PowerPC Netware powerpc-*-netware*
4362 Harris/CXUX m88k m88*-harris-cxux*
4363 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4364 ns32k-utek-sysv* ns32k-utek-*
4365 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4366 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4367 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4368 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4369 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4371 * Changes to command line processing
4373 The new `--args' feature can be used to specify command-line arguments
4374 for the inferior from gdb's command line.
4376 * Changes to key bindings
4378 There is a new `operate-and-get-next' function bound to `C-o'.
4380 *** Changes in GDB 5.1.1
4382 Fix compile problem on DJGPP.
4384 Fix a problem with floating-point registers on the i386 being
4387 Fix to stop GDB crashing on .debug_str debug info.
4389 Numerous documentation fixes.
4391 Numerous testsuite fixes.
4393 *** Changes in GDB 5.1:
4395 * New native configurations
4397 Alpha FreeBSD alpha*-*-freebsd*
4398 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4399 MIPS GNU/Linux mips*-*-linux*
4400 MIPS SGI Irix 6.x mips*-sgi-irix6*
4401 ia64 AIX ia64-*-aix*
4402 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4406 Motorola 68HC11 and 68HC12 m68hc11-elf
4408 UltraSparc running GNU/Linux sparc64-*-linux*
4410 * OBSOLETE configurations and files
4412 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4413 Harris/CXUX m88k m88*-harris-cxux*
4414 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4415 ns32k-utek-sysv* ns32k-utek-*
4416 TI TMS320C80 tic80-*-*
4418 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4419 PowerPC Solaris powerpcle-*-solaris*
4420 PowerPC Windows NT powerpcle-*-cygwin32
4421 PowerPC Netware powerpc-*-netware*
4422 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4423 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4424 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4425 Apple Macintosh (MPW) host N/A
4427 stuff.c (Program to stuff files into a specially prepared space in kdb)
4428 kdb-start.c (Main loop for the standalone kernel debugger)
4430 Configurations that have been declared obsolete in this release have
4431 been commented out. Unless there is activity to revive these
4432 configurations, the next release of GDB will have their sources
4433 permanently REMOVED.
4435 * REMOVED configurations and files
4437 Altos 3068 m68*-altos-*
4438 Convex c1-*-*, c2-*-*
4440 ARM RISCix arm-*-* (as host)
4444 * GDB has been converted to ISO C.
4446 GDB's source code has been converted to ISO C. In particular, the
4447 sources are fully protoized, and rely on standard headers being
4452 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4454 * The MI enabled by default.
4456 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4457 revised and enabled by default. Packages which use GDB as a debugging
4458 engine behind a UI or another front end are encouraged to switch to
4459 using the GDB/MI interface, instead of the old annotations interface
4460 which is now deprecated.
4462 * Support for debugging Pascal programs.
4464 GDB now includes support for debugging Pascal programs. The following
4465 main features are supported:
4467 - Pascal-specific data types such as sets;
4469 - automatic recognition of Pascal sources based on file-name
4472 - Pascal-style display of data types, variables, and functions;
4474 - a Pascal expression parser.
4476 However, some important features are not yet supported.
4478 - Pascal string operations are not supported at all;
4480 - there are some problems with boolean types;
4482 - Pascal type hexadecimal constants are not supported
4483 because they conflict with the internal variables format;
4485 - support for Pascal objects and classes is not full yet;
4487 - unlike Pascal, GDB is case-sensitive for symbol names.
4489 * Changes in completion.
4491 Commands such as `shell', `run' and `set args', which pass arguments
4492 to inferior programs, now complete on file names, similar to what
4493 users expect at the shell prompt.
4495 Commands which accept locations, such as `disassemble', `print',
4496 `breakpoint', `until', etc. now complete on filenames as well as
4497 program symbols. Thus, if you type "break foob TAB", and the source
4498 files linked into the programs include `foobar.c', that file name will
4499 be one of the candidates for completion. However, file names are not
4500 considered for completion after you typed a colon that delimits a file
4501 name from a name of a function in that file, as in "break foo.c:bar".
4503 `set demangle-style' completes on available demangling styles.
4505 * New platform-independent commands:
4507 It is now possible to define a post-hook for a command as well as a
4508 hook that runs before the command. For more details, see the
4509 documentation of `hookpost' in the GDB manual.
4511 * Changes in GNU/Linux native debugging.
4513 Support for debugging multi-threaded programs has been completely
4514 revised for all platforms except m68k and sparc. You can now debug as
4515 many threads as your system allows you to have.
4517 Attach/detach is supported for multi-threaded programs.
4519 Support for SSE registers was added for x86. This doesn't work for
4520 multi-threaded programs though.
4522 * Changes in MIPS configurations.
4524 Multi-arch support is enabled for all MIPS configurations.
4526 GDB can now be built as native debugger on SGI Irix 6.x systems for
4527 debugging n32 executables. (Debugging 64-bit executables is not yet
4530 * Unified support for hardware watchpoints in all x86 configurations.
4532 Most (if not all) native x86 configurations support hardware-assisted
4533 breakpoints and watchpoints in a unified manner. This support
4534 implements debug register sharing between watchpoints, which allows to
4535 put a virtually infinite number of watchpoints on the same address,
4536 and also supports watching regions up to 16 bytes with several debug
4539 The new maintenance command `maintenance show-debug-regs' toggles
4540 debugging print-outs in functions that insert, remove, and test
4541 watchpoints and hardware breakpoints.
4543 * Changes in the DJGPP native configuration.
4545 New command ``info dos sysinfo'' displays assorted information about
4546 the CPU, OS, memory, and DPMI server.
4548 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4549 display information about segment descriptors stored in GDT, LDT, and
4552 New commands ``info dos pde'' and ``info dos pte'' display entries
4553 from Page Directory and Page Tables (for now works with CWSDPMI only).
4554 New command ``info dos address-pte'' displays the Page Table entry for
4555 a given linear address.
4557 GDB can now pass command lines longer than 126 characters to the
4558 program being debugged (requires an update to the libdbg.a library
4559 which is part of the DJGPP development kit).
4561 DWARF2 debug info is now supported.
4563 It is now possible to `step' and `next' through calls to `longjmp'.
4565 * Changes in documentation.
4567 All GDB documentation was converted to GFDL, the GNU Free
4568 Documentation License.
4570 Tracepoints-related commands are now fully documented in the GDB
4573 TUI, the Text-mode User Interface, is now documented in the manual.
4575 Tracepoints-related commands are now fully documented in the GDB
4578 The "GDB Internals" manual now has an index. It also includes
4579 documentation of `ui_out' functions, GDB coding standards, x86
4580 hardware watchpoints, and memory region attributes.
4582 * GDB's version number moved to ``version.in''
4584 The Makefile variable VERSION has been replaced by the file
4585 ``version.in''. People creating GDB distributions should update the
4586 contents of this file.
4590 GUD support is now a standard part of the EMACS distribution.
4592 *** Changes in GDB 5.0:
4594 * Improved support for debugging FP programs on x86 targets
4596 Unified and much-improved support for debugging floating-point
4597 programs on all x86 targets. In particular, ``info float'' now
4598 displays the FP registers in the same format on all x86 targets, with
4599 greater level of detail.
4601 * Improvements and bugfixes in hardware-assisted watchpoints
4603 It is now possible to watch array elements, struct members, and
4604 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4605 on x86 targets no longer erroneously trigger when the address is
4608 * Improvements in the native DJGPP version of GDB
4610 The distribution now includes all the scripts and auxiliary files
4611 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4612 machines ``out of the box''.
4614 The DJGPP version can now debug programs that use signals. It is
4615 possible to catch signals that happened in the debuggee, deliver
4616 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4617 would kill the program being debugged.) Programs that hook hardware
4618 interrupts (keyboard, timer, etc.) can also be debugged.
4620 It is now possible to debug DJGPP programs that redirect their
4621 standard handles or switch them to raw (as opposed to cooked) mode, or
4622 even close them. The command ``run < foo > bar'' works as expected,
4623 and ``info terminal'' reports useful information about the debuggee's
4624 terminal, including raw/cooked mode, redirection, etc.
4626 The DJGPP version now uses termios functions for console I/O, which
4627 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4630 DOS-style file names with drive letters are now fully supported by
4633 It is now possible to debug DJGPP programs that switch their working
4634 directory. It is also possible to rerun the debuggee any number of
4635 times without restarting GDB; thus, you can use the same setup,
4636 breakpoints, etc. for many debugging sessions.
4638 * New native configurations
4640 ARM GNU/Linux arm*-*-linux*
4641 PowerPC GNU/Linux powerpc-*-linux*
4645 Motorola MCore mcore-*-*
4646 x86 VxWorks i[3456]86-*-vxworks*
4647 PowerPC VxWorks powerpc-*-vxworks*
4648 TI TMS320C80 tic80-*-*
4650 * OBSOLETE configurations
4652 Altos 3068 m68*-altos-*
4653 Convex c1-*-*, c2-*-*
4655 ARM RISCix arm-*-* (as host)
4658 Configurations that have been declared obsolete will be commented out,
4659 but the code will be left in place. If there is no activity to revive
4660 these configurations before the next release of GDB, the sources will
4661 be permanently REMOVED.
4663 * Gould support removed
4665 Support for the Gould PowerNode and NP1 has been removed.
4667 * New features for SVR4
4669 On SVR4 native platforms (such as Solaris), if you attach to a process
4670 without first loading a symbol file, GDB will now attempt to locate and
4671 load symbols from the running process's executable file.
4673 * Many C++ enhancements
4675 C++ support has been greatly improved. Overload resolution now works properly
4676 in almost all cases. RTTI support is on the way.
4678 * Remote targets can connect to a sub-program
4680 A popen(3) style serial-device has been added. This device starts a
4681 sub-process (such as a stand-alone simulator) and then communicates
4682 with that. The sub-program to run is specified using the syntax
4683 ``|<program> <args>'' vis:
4685 (gdb) set remotedebug 1
4686 (gdb) target extended-remote |mn10300-elf-sim program-args
4688 * MIPS 64 remote protocol
4690 A long standing bug in the mips64 remote protocol where by GDB
4691 expected certain 32 bit registers (ex SR) to be transfered as 32
4692 instead of 64 bits has been fixed.
4694 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4695 added to provide backward compatibility with older versions of GDB.
4697 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4699 The command ``set remotebinarydownload'' command has been replaced by
4700 ``set remote X-packet''. Other commands in ``set remote'' family
4701 include ``set remote P-packet''.
4703 * Breakpoint commands accept ranges.
4705 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4706 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4707 ``tracepoint passcount'' also accepts a range of tracepoints.
4709 * ``apropos'' command added.
4711 The ``apropos'' command searches through command names and
4712 documentation strings, printing out matches, making it much easier to
4713 try to find a command that does what you are looking for.
4717 A new machine oriented interface (MI) has been added to GDB. This
4718 interface is designed for debug environments running GDB as a separate
4719 process. This is part of the long term libGDB project. See the
4720 "GDB/MI" chapter of the GDB manual for further information. It can be
4721 enabled by configuring with:
4723 .../configure --enable-gdbmi
4725 *** Changes in GDB-4.18:
4727 * New native configurations
4729 HP-UX 10.20 hppa*-*-hpux10.20
4730 HP-UX 11.x hppa*-*-hpux11.0*
4731 M68K GNU/Linux m68*-*-linux*
4735 Fujitsu FR30 fr30-*-elf*
4736 Intel StrongARM strongarm-*-*
4737 Mitsubishi D30V d30v-*-*
4739 * OBSOLETE configurations
4741 Gould PowerNode, NP1 np1-*-*, pn-*-*
4743 Configurations that have been declared obsolete will be commented out,
4744 but the code will be left in place. If there is no activity to revive
4745 these configurations before the next release of GDB, the sources will
4746 be permanently REMOVED.
4750 As a compatibility experiment, GDB's source files buildsym.h and
4751 buildsym.c have been converted to pure standard C, no longer
4752 containing any K&R compatibility code. We believe that all systems in
4753 use today either come with a standard C compiler, or have a GCC port
4754 available. If this is not true, please report the affected
4755 configuration to bug-gdb@gnu.org immediately. See the README file for
4756 information about getting a standard C compiler if you don't have one
4761 GDB now uses readline 2.2.
4763 * set extension-language
4765 You can now control the mapping between filename extensions and source
4766 languages by using the `set extension-language' command. For instance,
4767 you can ask GDB to treat .c files as C++ by saying
4768 set extension-language .c c++
4769 The command `info extensions' lists all of the recognized extensions
4770 and their associated languages.
4772 * Setting processor type for PowerPC and RS/6000
4774 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4775 you can use the `set processor' command to specify what variant of the
4776 PowerPC family you are debugging. The command
4780 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4781 following PowerPC and RS6000 variants:
4783 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4784 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4786 403GC IBM PowerPC 403GC
4787 505 Motorola PowerPC 505
4788 860 Motorola PowerPC 860 or 850
4789 601 Motorola PowerPC 601
4790 602 Motorola PowerPC 602
4791 603 Motorola/IBM PowerPC 603 or 603e
4792 604 Motorola PowerPC 604 or 604e
4793 750 Motorola/IBM PowerPC 750 or 750
4795 At the moment, this command just tells GDB what to name the
4796 special-purpose processor registers. Since almost all the affected
4797 registers are inaccessible to user-level programs, this command is
4798 only useful for remote debugging in its present form.
4802 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4803 more extensive support for HP-UX. Added features include shared
4804 library support, kernel threads and hardware watchpoints for 11.00,
4805 support for HP's ANSI C and C++ compilers, and a compatibility mode
4806 for xdb and dbx commands.
4810 HP's donation includes the new concept of catchpoints, which is a
4811 generalization of the old catch command. On HP-UX, it is now possible
4812 to catch exec, fork, and vfork, as well as library loading.
4814 This means that the existing catch command has changed; its first
4815 argument now specifies the type of catch to be set up. See the
4816 output of "help catch" for a list of catchpoint types.
4818 * Debugging across forks
4820 On HP-UX, you can choose which process to debug when a fork() happens
4825 HP has donated a curses-based terminal user interface (TUI). To get
4826 it, build with --enable-tui. Although this can be enabled for any
4827 configuration, at present it only works for native HP debugging.
4829 * GDB remote protocol additions
4831 A new protocol packet 'X' that writes binary data is now available.
4832 Default behavior is to try 'X', then drop back to 'M' if the stub
4833 fails to respond. The settable variable `remotebinarydownload'
4834 allows explicit control over the use of 'X'.
4836 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4837 full 64-bit address. The command
4839 set remoteaddresssize 32
4841 can be used to revert to the old behaviour. For existing remote stubs
4842 the change should not be noticed, as the additional address information
4845 In order to assist in debugging stubs, you may use the maintenance
4846 command `packet' to send any text string to the stub. For instance,
4848 maint packet heythere
4850 sends the packet "$heythere#<checksum>". Note that it is very easy to
4851 disrupt a debugging session by sending the wrong packet at the wrong
4854 The compare-sections command allows you to compare section data on the
4855 target to what is in the executable file without uploading or
4856 downloading, by comparing CRC checksums.
4858 * Tracing can collect general expressions
4860 You may now collect general expressions at tracepoints. This requires
4861 further additions to the target-side stub; see tracepoint.c and
4862 doc/agentexpr.texi for further details.
4864 * mask-address variable for Mips
4866 For Mips targets, you may control the zeroing of the upper 32 bits of
4867 a 64-bit address by entering `set mask-address on'. This is mainly
4868 of interest to users of embedded R4xxx and R5xxx processors.
4870 * Higher serial baud rates
4872 GDB's serial code now allows you to specify baud rates 57600, 115200,
4873 230400, and 460800 baud. (Note that your host system may not be able
4874 to achieve all of these rates.)
4878 The i960 configuration now includes an initial implementation of a
4879 builtin simulator, contributed by Jim Wilson.
4882 *** Changes in GDB-4.17:
4884 * New native configurations
4886 Alpha GNU/Linux alpha*-*-linux*
4887 Unixware 2.x i[3456]86-unixware2*
4888 Irix 6.x mips*-sgi-irix6*
4889 PowerPC GNU/Linux powerpc-*-linux*
4890 PowerPC Solaris powerpcle-*-solaris*
4891 Sparc GNU/Linux sparc-*-linux*
4892 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4896 Argonaut Risc Chip (ARC) arc-*-*
4897 Hitachi H8/300S h8300*-*-*
4898 Matsushita MN10200 w/simulator mn10200-*-*
4899 Matsushita MN10300 w/simulator mn10300-*-*
4900 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4901 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4902 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4903 Mitsubishi D10V w/simulator d10v-*-*
4904 Mitsubishi M32R/D w/simulator m32r-*-elf*
4905 Tsqware Sparclet sparclet-*-*
4906 NEC V850 w/simulator v850-*-*
4908 * New debugging protocols
4910 ARM with RDI protocol arm*-*-*
4911 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4912 DDB and LSI variants of PMON protocol mips*-*-*
4913 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4914 PowerPC with SDS protocol powerpc{,le}-*-eabi
4915 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4919 All configurations can now understand and use the DWARF 2 debugging
4920 format. The choice is automatic, if the symbol file contains DWARF 2
4925 GDB now includes basic Java language support. This support is
4926 only useful with Java compilers that produce native machine code.
4928 * solib-absolute-prefix and solib-search-path
4930 For SunOS and SVR4 shared libraries, you may now set the prefix for
4931 loading absolute shared library symbol files, and the search path for
4932 locating non-absolute shared library symbol files.
4934 * Live range splitting
4936 GDB can now effectively debug code for which GCC has performed live
4937 range splitting as part of its optimization. See gdb/doc/LRS for
4938 more details on the expected format of the stabs information.
4942 GDB's support for the GNU Hurd, including thread debugging, has been
4943 updated to work with current versions of the Hurd.
4947 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4948 instruction set. ARM GDB automatically detects when Thumb
4949 instructions are in use, and adjusts disassembly and backtracing
4954 GDB's MIPS target configurations now handle the MIP16 16-bit
4959 GDB now includes support for overlays; if an executable has been
4960 linked such that multiple sections are based at the same address, GDB
4961 will decide which section to use for symbolic info. You can choose to
4962 control the decision manually, using overlay commands, or implement
4963 additional target-side support and use "overlay load-target" to bring
4964 in the overlay mapping. Do "help overlay" for more detail.
4968 The command "info symbol <address>" displays information about
4969 the symbol at the specified address.
4973 The standard remote protocol now includes an extension that allows
4974 asynchronous collection and display of trace data. This requires
4975 extensive support in the target-side debugging stub. Tracing mode
4976 includes a new interaction mode in GDB and new commands: see the
4977 file tracepoint.c for more details.
4981 Configurations for embedded MIPS now include a simulator contributed
4982 by Cygnus Solutions. The simulator supports the instruction sets
4983 of most MIPS variants.
4987 Sparc configurations may now include the ERC32 simulator contributed
4988 by the European Space Agency. The simulator is not built into
4989 Sparc targets by default; configure with --enable-sim to include it.
4993 For target configurations that may include multiple variants of a
4994 basic architecture (such as MIPS and SH), you may now set the
4995 architecture explicitly. "set arch" sets, "info arch" lists
4996 the possible architectures.
4998 *** Changes in GDB-4.16:
5000 * New native configurations
5002 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5003 M68K NetBSD m68k-*-netbsd*
5004 PowerPC AIX 4.x powerpc-*-aix*
5005 PowerPC MacOS powerpc-*-macos*
5006 PowerPC Windows NT powerpcle-*-cygwin32
5007 RS/6000 AIX 4.x rs6000-*-aix4*
5011 ARM with RDP protocol arm-*-*
5012 I960 with MON960 i960-*-coff
5013 MIPS VxWorks mips*-*-vxworks*
5014 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5015 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5017 Matra Sparclet sparclet-*-*
5021 The powerpc-eabi configuration now includes the PSIM simulator,
5022 contributed by Andrew Cagney, with assistance from Mike Meissner.
5023 PSIM is a very elaborate model of the PowerPC, including not only
5024 basic instruction set execution, but also details of execution unit
5025 performance and I/O hardware. See sim/ppc/README for more details.
5029 GDB now works with Solaris 2.5.
5031 * Windows 95/NT native
5033 GDB will now work as a native debugger on Windows 95 and Windows NT.
5034 To build it from source, you must use the "gnu-win32" environment,
5035 which uses a DLL to emulate enough of Unix to run the GNU tools.
5036 Further information, binaries, and sources are available at
5037 ftp.cygnus.com, under pub/gnu-win32.
5039 * dont-repeat command
5041 If a user-defined command includes the command `dont-repeat', then the
5042 command will not be repeated if the user just types return. This is
5043 useful if the command is time-consuming to run, so that accidental
5044 extra keystrokes don't run the same command many times.
5046 * Send break instead of ^C
5048 The standard remote protocol now includes an option to send a break
5049 rather than a ^C to the target in order to interrupt it. By default,
5050 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5052 * Remote protocol timeout
5054 The standard remote protocol includes a new variable `remotetimeout'
5055 that allows you to set the number of seconds before GDB gives up trying
5056 to read from the target. The default value is 2.
5058 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5060 By default GDB will automatically keep track of objects as they are
5061 loaded and unloaded by the dynamic linker. By using the command `set
5062 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5063 when shared library events occur, thus allowing you to set breakpoints
5064 in shared libraries which are explicitly loaded by the inferior.
5066 Note this feature does not work on hpux8. On hpux9 you must link
5067 /usr/lib/end.o into your program. This feature should work
5068 automatically on hpux10.
5070 * Irix 5.x hardware watchpoint support
5072 Irix 5 configurations now support the use of hardware watchpoints.
5074 * Mips protocol "SYN garbage limit"
5076 When debugging a Mips target using the `target mips' protocol, you
5077 may set the number of characters that GDB will ignore by setting
5078 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5079 every character. The default value is 1050.
5081 * Recording and replaying remote debug sessions
5083 If you set `remotelogfile' to the name of a file, gdb will write to it
5084 a recording of a remote debug session. This recording may then be
5085 replayed back to gdb using "gdbreplay". See gdbserver/README for
5086 details. This is useful when you have a problem with GDB while doing
5087 remote debugging; you can make a recording of the session and send it
5088 to someone else, who can then recreate the problem.
5090 * Speedups for remote debugging
5092 GDB includes speedups for downloading and stepping MIPS systems using
5093 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5094 and more efficient S-record downloading.
5096 * Memory use reductions and statistics collection
5098 GDB now uses less memory and reports statistics about memory usage.
5099 Try the `maint print statistics' command, for example.
5101 *** Changes in GDB-4.15:
5103 * Psymtabs for XCOFF
5105 The symbol reader for AIX GDB now uses partial symbol tables. This
5106 can greatly improve startup time, especially for large executables.
5108 * Remote targets use caching
5110 Remote targets now use a data cache to speed up communication with the
5111 remote side. The data cache could lead to incorrect results because
5112 it doesn't know about volatile variables, thus making it impossible to
5113 debug targets which use memory mapped I/O devices. `set remotecache
5114 off' turns the the data cache off.
5116 * Remote targets may have threads
5118 The standard remote protocol now includes support for multiple threads
5119 in the target system, using new protocol commands 'H' and 'T'. See
5120 gdb/remote.c for details.
5124 If GDB is configured with `--enable-netrom', then it will include
5125 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5126 acts as though it is a bank of ROM on the target board, but you can
5127 write into it over the network. GDB's support consists only of
5128 support for fast loading into the emulated ROM; to debug, you must use
5129 another protocol, such as standard remote protocol. The usual
5130 sequence is something like
5132 target nrom <netrom-hostname>
5134 target remote <netrom-hostname>:1235
5138 GDB now includes support for the Apple Macintosh, as a host only. It
5139 may be run as either an MPW tool or as a standalone application, and
5140 it can debug through the serial port. All the usual GDB commands are
5141 available, but to the target command, you must supply "serial" as the
5142 device type instead of "/dev/ttyXX". See mpw-README in the main
5143 directory for more information on how to build. The MPW configuration
5144 scripts */mpw-config.in support only a few targets, and only the
5145 mips-idt-ecoff target has been tested.
5149 GDB configuration now uses autoconf. This is not user-visible,
5150 but does simplify configuration and building.
5154 GDB now supports hpux10.
5156 *** Changes in GDB-4.14:
5158 * New native configurations
5160 x86 FreeBSD i[345]86-*-freebsd
5161 x86 NetBSD i[345]86-*-netbsd
5162 NS32k NetBSD ns32k-*-netbsd
5163 Sparc NetBSD sparc-*-netbsd
5167 A29K VxWorks a29k-*-vxworks
5168 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5169 CPU32 EST-300 emulator m68*-*-est*
5170 PowerPC ELF powerpc-*-elf
5173 * Alpha OSF/1 support for procfs
5175 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5176 possible to attach to running processes. As the mounting of the /proc
5177 filesystem is optional on the Alpha, GDB automatically determines
5178 the availability of /proc during startup. This can lead to problems
5179 if /proc is unmounted after GDB has been started.
5181 * Arguments to user-defined commands
5183 User commands may accept up to 10 arguments separated by whitespace.
5184 Arguments are accessed within the user command via $arg0..$arg9. A
5187 print $arg0 + $arg1 + $arg2
5189 To execute the command use:
5192 Defines the command "adder" which prints the sum of its three arguments.
5193 Note the arguments are text substitutions, so they may reference variables,
5194 use complex expressions, or even perform inferior function calls.
5196 * New `if' and `while' commands
5198 This makes it possible to write more sophisticated user-defined
5199 commands. Both commands take a single argument, which is the
5200 expression to evaluate, and must be followed by the commands to
5201 execute, one per line, if the expression is nonzero, the list being
5202 terminated by the word `end'. The `if' command list may include an
5203 `else' word, which causes the following commands to be executed only
5204 if the expression is zero.
5206 * Fortran source language mode
5208 GDB now includes partial support for Fortran 77. It will recognize
5209 Fortran programs and can evaluate a subset of Fortran expressions, but
5210 variables and functions may not be handled correctly. GDB will work
5211 with G77, but does not yet know much about symbols emitted by other
5214 * Better HPUX support
5216 Most debugging facilities now work on dynamic executables for HPPAs
5217 running hpux9 or later. You can attach to running dynamically linked
5218 processes, but by default the dynamic libraries will be read-only, so
5219 for instance you won't be able to put breakpoints in them. To change
5220 that behavior do the following before running the program:
5226 This will cause the libraries to be mapped private and read-write.
5227 To revert to the normal behavior, do this:
5233 You cannot set breakpoints or examine data in the library until after
5234 the library is loaded if the function/data symbols do not have
5237 GDB can now also read debug symbols produced by the HP C compiler on
5238 HPPAs (sorry, no C++, Fortran or 68k support).
5240 * Target byte order now dynamically selectable
5242 You can choose which byte order to use with a target system, via the
5243 commands "set endian big" and "set endian little", and you can see the
5244 current setting by using "show endian". You can also give the command
5245 "set endian auto", in which case GDB will use the byte order
5246 associated with the executable. Currently, only embedded MIPS
5247 configurations support dynamic selection of target byte order.
5249 * New DOS host serial code
5251 This version uses DPMI interrupts to handle buffered I/O, so you
5252 no longer need to run asynctsr when debugging boards connected to
5255 *** Changes in GDB-4.13:
5257 * New "complete" command
5259 This lists all the possible completions for the rest of the line, if it
5260 were to be given as a command itself. This is intended for use by emacs.
5262 * Trailing space optional in prompt
5264 "set prompt" no longer adds a space for you after the prompt you set. This
5265 allows you to set a prompt which ends in a space or one that does not.
5267 * Breakpoint hit counts
5269 "info break" now displays a count of the number of times the breakpoint
5270 has been hit. This is especially useful in conjunction with "ignore"; you
5271 can ignore a large number of breakpoint hits, look at the breakpoint info
5272 to see how many times the breakpoint was hit, then run again, ignoring one
5273 less than that number, and this will get you quickly to the last hit of
5276 * Ability to stop printing at NULL character
5278 "set print null-stop" will cause GDB to stop printing the characters of
5279 an array when the first NULL is encountered. This is useful when large
5280 arrays actually contain only short strings.
5282 * Shared library breakpoints
5284 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5285 breakpoints in shared libraries before the executable is run.
5287 * Hardware watchpoints
5289 There is a new hardware breakpoint for the watch command for sparclite
5290 targets. See gdb/sparclite/hw_breakpoint.note.
5292 Hardware watchpoints are also now supported under GNU/Linux.
5296 Annotations have been added. These are for use with graphical interfaces,
5297 and are still experimental. Currently only gdba.el uses these.
5299 * Improved Irix 5 support
5301 GDB now works properly with Irix 5.2.
5303 * Improved HPPA support
5305 GDB now works properly with the latest GCC and GAS.
5307 * New native configurations
5309 Sequent PTX4 i[34]86-sequent-ptx4
5310 HPPA running OSF/1 hppa*-*-osf*
5311 Atari TT running SVR4 m68*-*-sysv4*
5312 RS/6000 LynxOS rs6000-*-lynxos*
5316 OS/9000 i[34]86-*-os9k
5317 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5320 * Hitachi SH7000 and E7000-PC ICE support
5322 There is now support for communicating with the Hitachi E7000-PC ICE.
5323 This is available automatically when GDB is configured for the SH.
5327 As usual, a variety of small fixes and improvements, both generic
5328 and configuration-specific. See the ChangeLog for more detail.
5330 *** Changes in GDB-4.12:
5332 * Irix 5 is now supported
5336 GDB-4.12 on the HPPA has a number of changes which make it unable
5337 to debug the output from the currently released versions of GCC and
5338 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5339 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5340 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5343 *** Changes in GDB-4.11:
5345 * User visible changes:
5349 The "set remotedebug" option is now consistent between the mips remote
5350 target, remote targets using the gdb-specific protocol, UDI (AMD's
5351 debug protocol for the 29k) and the 88k bug monitor. It is now an
5352 integer specifying a debug level (normally 0 or 1, but 2 means more
5353 debugging info for the mips target).
5355 * DEC Alpha native support
5357 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5358 debug info, but GDB works fairly well with the DEC compiler and should
5359 work with a future GCC release. See the README file for a few
5360 Alpha-specific notes.
5362 * Preliminary thread implementation
5364 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5366 * LynxOS native and target support for 386
5368 This release has been hosted on LynxOS 2.2, and also can be configured
5369 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5372 * Improvements in C++ mangling/demangling.
5374 This release has much better g++ debugging, specifically in name
5375 mangling/demangling, virtual function calls, print virtual table,
5376 call methods, ...etc.
5378 *** Changes in GDB-4.10:
5380 * User visible changes:
5382 Remote debugging using the GDB-specific (`target remote') protocol now
5383 supports the `load' command. This is only useful if you have some
5384 other way of getting the stub to the target system, and you can put it
5385 somewhere in memory where it won't get clobbered by the download.
5387 Filename completion now works.
5389 When run under emacs mode, the "info line" command now causes the
5390 arrow to point to the line specified. Also, "info line" prints
5391 addresses in symbolic form (as well as hex).
5393 All vxworks based targets now support a user settable option, called
5394 vxworks-timeout. This option represents the number of seconds gdb
5395 should wait for responses to rpc's. You might want to use this if
5396 your vxworks target is, perhaps, a slow software simulator or happens
5397 to be on the far side of a thin network line.
5401 This release contains support for using a DEC alpha as a GDB host for
5402 cross debugging. Native alpha debugging is not supported yet.
5405 *** Changes in GDB-4.9:
5409 This is the first GDB release which is accompanied by a matching testsuite.
5410 The testsuite requires installation of dejagnu, which should be available
5411 via ftp from most sites that carry GNU software.
5415 'Cfront' style demangling has had its name changed to 'ARM' style, to
5416 emphasize that it was written from the specifications in the C++ Annotated
5417 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5418 disclaimers, it still generated too much confusion with users attempting to
5419 use gdb with AT&T cfront.
5423 GDB now uses a standard remote interface to a simulator library.
5424 So far, the library contains simulators for the Zilog Z8001/2, the
5425 Hitachi H8/300, H8/500 and Super-H.
5427 * New targets supported
5429 H8/300 simulator h8300-hitachi-hms or h8300hms
5430 H8/500 simulator h8500-hitachi-hms or h8500hms
5431 SH simulator sh-hitachi-hms or sh
5432 Z8000 simulator z8k-zilog-none or z8ksim
5433 IDT MIPS board over serial line mips-idt-ecoff
5435 Cross-debugging to GO32 targets is supported. It requires a custom
5436 version of the i386-stub.c module which is integrated with the
5437 GO32 memory extender.
5439 * New remote protocols
5441 MIPS remote debugging protocol.
5443 * New source languages supported
5445 This version includes preliminary support for Chill, a Pascal like language
5446 used by telecommunications companies. Chill support is also being integrated
5447 into the GNU compiler, but we don't know when it will be publically available.
5450 *** Changes in GDB-4.8:
5452 * HP Precision Architecture supported
5454 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5455 version of this support was available as a set of patches from the
5456 University of Utah. GDB does not support debugging of programs
5457 compiled with the HP compiler, because HP will not document their file
5458 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5459 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5461 Many problems in the preliminary version have been fixed.
5463 * Faster and better demangling
5465 We have improved template demangling and fixed numerous bugs in the GNU style
5466 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5467 character types (wchar_t) are now supported. Demangling of each symbol is now
5468 only done once, and is cached when the symbol table for a file is read in.
5469 This results in a small increase in memory usage for C programs, a moderate
5470 increase in memory usage for C++ programs, and a fantastic speedup in
5473 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5474 from the specifications in the Annotated Reference Manual, which AT&T's
5475 compiler does not actually implement.
5477 * G++ multiple inheritance compiler problem
5479 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5480 inheritance lattices was reworked to properly discover ambiguities. We
5481 recently found an example which causes this new algorithm to fail in a
5482 very subtle way, producing bad debug information for those classes.
5483 The file 'gcc.patch' (in this directory) can be applied to gcc to
5484 circumvent the problem. A future GCC release will contain a complete
5487 The previous G++ debug info problem (mentioned below for the gdb-4.7
5488 release) is fixed in gcc version 2.3.2.
5490 * Improved configure script
5492 The `configure' script will now attempt to guess your system type if
5493 you don't supply a host system type. The old scheme of supplying a
5494 host system triplet is preferable over using this. All the magic is
5495 done in the new `config.guess' script. Examine it for details.
5497 We have also brought our configure script much more in line with the FSF's
5498 version. It now supports the --with-xxx options. In particular,
5499 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5500 The resulting GDB will not be able to read arbitrary object file formats --
5501 only the format ``expected'' to be used on the configured target system.
5502 We hope to make this the default in a future release.
5504 * Documentation improvements
5506 There's new internal documentation on how to modify GDB, and how to
5507 produce clean changes to the code. We implore people to read it
5508 before submitting changes.
5510 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5511 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5512 `info' files are also provided. To build `info' files from scratch,
5513 you will need the latest `makeinfo' release, which will be available in
5514 a future texinfo-X.Y release.
5516 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5517 We're not sure exactly which versions have this problem, but it has
5518 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5519 or better. If that isn't possible, there is a patch in
5520 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5521 around this problem.
5525 GDB now supports array constants that can be used in expressions typed in by
5526 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5527 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5530 The new directory `gdb/sparclite' contains a program that demonstrates
5531 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5533 * New native hosts supported
5535 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5536 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5538 * New targets supported
5540 AMD 29k family via UDI a29k-amd-udi or udi29k
5542 * New file formats supported
5544 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5545 HPUX core files, and SCO 3.2v2 core files.
5549 Attaching to processes now works again; thanks for the many bug reports.
5551 We have also stomped on a bunch of core dumps caused by
5552 printf_filtered("%s") problems.
5554 We eliminated a copyright problem on the rpc and ptrace header files
5555 for VxWorks, which was discovered at the last minute during the 4.7
5556 release. You should now be able to build a VxWorks GDB.
5558 You can now interrupt gdb while an attached process is running. This
5559 will cause the attached process to stop, and give control back to GDB.
5561 We fixed problems caused by using too many file descriptors
5562 for reading symbols from object files and libraries. This was
5563 especially a problem for programs that used many (~100) shared
5566 The `step' command now only enters a subroutine if there is line number
5567 information for the subroutine. Otherwise it acts like the `next'
5568 command. Previously, `step' would enter subroutines if there was
5569 any debugging information about the routine. This avoids problems
5570 when using `cc -g1' on MIPS machines.
5572 * Internal improvements
5574 GDB's internal interfaces have been improved to make it easier to support
5575 debugging of multiple languages in the future.
5577 GDB now uses a common structure for symbol information internally.
5578 Minimal symbols (derived from linkage symbols in object files), partial
5579 symbols (from a quick scan of debug information), and full symbols
5580 contain a common subset of information, making it easier to write
5581 shared code that handles any of them.
5583 * New command line options
5585 We now accept --silent as an alias for --quiet.
5589 The memory-mapped-malloc library is now licensed under the GNU Library
5590 General Public License.
5592 *** Changes in GDB-4.7:
5594 * Host/native/target split
5596 GDB has had some major internal surgery to untangle the support for
5597 hosts and remote targets. Now, when you configure GDB for a remote
5598 target, it will no longer load in all of the support for debugging
5599 local programs on the host. When fully completed and tested, this will
5600 ensure that arbitrary host/target combinations are possible.
5602 The primary conceptual shift is to separate the non-portable code in
5603 GDB into three categories. Host specific code is required any time GDB
5604 is compiled on that host, regardless of the target. Target specific
5605 code relates to the peculiarities of the target, but can be compiled on
5606 any host. Native specific code is everything else: it can only be
5607 built when the host and target are the same system. Child process
5608 handling and core file support are two common `native' examples.
5610 GDB's use of /proc for controlling Unix child processes is now cleaner.
5611 It has been split out into a single module under the `target_ops' vector,
5612 plus two native-dependent functions for each system that uses /proc.
5614 * New hosts supported
5616 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5617 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5618 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5620 * New targets supported
5622 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5623 68030 and CPU32 m68030-*-*, m68332-*-*
5625 * New native hosts supported
5627 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5628 (386bsd is not well tested yet)
5629 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5631 * New file formats supported
5633 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5634 supports reading of `a.out.adobe' object files, which are an a.out
5635 format extended with minimal information about multiple sections.
5639 `show copying' is the same as the old `info copying'.
5640 `show warranty' is the same as `info warrantee'.
5641 These were renamed for consistency. The old commands continue to work.
5643 `info handle' is a new alias for `info signals'.
5645 You can now define pre-command hooks, which attach arbitrary command
5646 scripts to any command. The commands in the hook will be executed
5647 prior to the user's command. You can also create a hook which will be
5648 executed whenever the program stops. See gdb.texinfo.
5652 We now deal with Cfront style name mangling, and can even extract type
5653 info from mangled symbols. GDB can automatically figure out which
5654 symbol mangling style your C++ compiler uses.
5656 Calling of methods and virtual functions has been improved as well.
5660 The crash that occured when debugging Sun Ansi-C compiled binaries is
5661 fixed. This was due to mishandling of the extra N_SO stabs output
5664 We also finally got Ultrix 4.2 running in house, and fixed core file
5665 support, with help from a dozen people on the net.
5667 John M. Farrell discovered that the reason that single-stepping was so
5668 slow on all of the Mips based platforms (primarily SGI and DEC) was
5669 that we were trying to demangle and lookup a symbol used for internal
5670 purposes on every instruction that was being stepped through. Changing
5671 the name of that symbol so that it couldn't be mistaken for a C++
5672 mangled symbol sped things up a great deal.
5674 Rich Pixley sped up symbol lookups in general by getting much smarter
5675 about when C++ symbol mangling is necessary. This should make symbol
5676 completion (TAB on the command line) much faster. It's not as fast as
5677 we'd like, but it's significantly faster than gdb-4.6.
5681 A new user controllable variable 'call_scratch_address' can
5682 specify the location of a scratch area to be used when GDB
5683 calls a function in the target. This is necessary because the
5684 usual method of putting the scratch area on the stack does not work
5685 in systems that have separate instruction and data spaces.
5687 We integrated changes to support the 29k UDI (Universal Debugger
5688 Interface), but discovered at the last minute that we didn't have all
5689 of the appropriate copyright paperwork. We are working with AMD to
5690 resolve this, and hope to have it available soon.
5694 We have sped up the remote serial line protocol, especially for targets
5695 with lots of registers. It now supports a new `expedited status' ('T')
5696 message which can be used in place of the existing 'S' status message.
5697 This allows the remote stub to send only the registers that GDB
5698 needs to make a quick decision about single-stepping or conditional
5699 breakpoints, eliminating the need to fetch the entire register set for
5700 each instruction being stepped through.
5702 The GDB remote serial protocol now implements a write-through cache for
5703 registers, only re-reading the registers if the target has run.
5705 There is also a new remote serial stub for SPARC processors. You can
5706 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5707 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5708 processor with a serial port.
5712 Configure.in files have become much easier to read and modify. A new
5713 `table driven' format makes it more obvious what configurations are
5714 supported, and what files each one uses.
5718 There is a new opcodes library which will eventually contain all of the
5719 disassembly routines and opcode tables. At present, it only contains
5720 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5721 disassembler (binutils/objdump) to share these routines.
5723 The libiberty library is now copylefted under the GNU Library General
5724 Public License. This allows more liberal use, and was done so libg++
5725 can use it. This makes no difference to GDB, since the Library License
5726 grants all the rights from the General Public License.
5730 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5731 reference to the stabs symbol info used by the debugger. It is (as far
5732 as we know) the only published document on this fascinating topic. We
5733 encourage you to read it, compare it to the stabs information on your
5734 system, and send improvements on the document in general (to
5735 bug-gdb@prep.ai.mit.edu).
5737 And, of course, many bugs have been fixed.
5740 *** Changes in GDB-4.6:
5742 * Better support for C++ function names
5744 GDB now accepts as input the "demangled form" of C++ overloaded function
5745 names and member function names, and can do command completion on such names
5746 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5747 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5748 Make use of command completion, it is your friend.
5750 GDB also now accepts a variety of C++ mangled symbol formats. They are
5751 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5752 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5753 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5754 for the list of formats.
5756 * G++ symbol mangling problem
5758 Recent versions of gcc have a bug in how they emit debugging information for
5759 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5760 directory) can be applied to gcc to fix the problem. Alternatively, if you
5761 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5762 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5763 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5766 * New 'maintenance' command
5768 All of the commands related to hacking GDB internals have been moved out of
5769 the main command set, and now live behind the 'maintenance' command. This
5770 can also be abbreviated as 'mt'. The following changes were made:
5772 dump-me -> maintenance dump-me
5773 info all-breakpoints -> maintenance info breakpoints
5774 printmsyms -> maintenance print msyms
5775 printobjfiles -> maintenance print objfiles
5776 printpsyms -> maintenance print psymbols
5777 printsyms -> maintenance print symbols
5779 The following commands are new:
5781 maintenance demangle Call internal GDB demangler routine to
5782 demangle a C++ link name and prints the result.
5783 maintenance print type Print a type chain for a given symbol
5785 * Change to .gdbinit file processing
5787 We now read the $HOME/.gdbinit file before processing the argv arguments
5788 (e.g. reading symbol files or core files). This allows global parameters to
5789 be set, which will apply during the symbol reading. The ./.gdbinit is still
5790 read after argv processing.
5792 * New hosts supported
5794 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5796 GNU/Linux support i386-unknown-linux or linux
5798 We are also including code to support the HP/PA running BSD and HPUX. This
5799 is almost guaranteed not to work, as we didn't have time to test or build it
5800 for this release. We are including it so that the more adventurous (or
5801 masochistic) of you can play with it. We also had major problems with the
5802 fact that the compiler that we got from HP doesn't support the -g option.
5805 * New targets supported
5807 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5809 * More smarts about finding #include files
5811 GDB now remembers the compilation directory for all include files, and for
5812 all files from which C is generated (like yacc and lex sources). This
5813 greatly improves GDB's ability to find yacc/lex sources, and include files,
5814 especially if you are debugging your program from a directory different from
5815 the one that contains your sources.
5817 We also fixed a bug which caused difficulty with listing and setting
5818 breakpoints in include files which contain C code. (In the past, you had to
5819 try twice in order to list an include file that you hadn't looked at before.)
5821 * Interesting infernals change
5823 GDB now deals with arbitrary numbers of sections, where the symbols for each
5824 section must be relocated relative to that section's landing place in the
5825 target's address space. This work was needed to support ELF with embedded
5826 stabs used by Solaris-2.0.
5828 * Bug fixes (of course!)
5830 There have been loads of fixes for the following things:
5831 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5832 i960, stabs, DOS(GO32), procfs, etc...
5834 See the ChangeLog for details.
5836 *** Changes in GDB-4.5:
5838 * New machines supported (host and target)
5840 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5842 SGI Irix-4.x mips-sgi-irix4 or iris4
5844 * New malloc package
5846 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5847 Mmalloc is capable of handling mutiple heaps of memory. It is also
5848 capable of saving a heap to a file, and then mapping it back in later.
5849 This can be used to greatly speedup the startup of GDB by using a
5850 pre-parsed symbol table which lives in a mmalloc managed heap. For
5851 more details, please read mmalloc/mmalloc.texi.
5855 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5856 'help info proc' for details.
5858 * MIPS ecoff symbol table format
5860 The code that reads MIPS symbol table format is now supported on all hosts.
5861 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5864 * File name changes for MS-DOS
5866 Many files in the config directories have been renamed to make it easier to
5867 support GDB on MS-DOSe systems (which have very restrictive file name
5868 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5869 environment) is close to working but has some remaining problems. Note
5870 that debugging of DOS programs is not supported, due to limitations
5871 in the ``operating system'', but it can be used to host cross-debugging.
5873 * Cross byte order fixes
5875 Many fixes have been made to support cross debugging of Sparc and MIPS
5876 targets from hosts whose byte order differs.
5878 * New -mapped and -readnow options
5880 If memory-mapped files are available on your system through the 'mmap'
5881 system call, you can use the -mapped option on the `file' or
5882 `symbol-file' commands to cause GDB to write the symbols from your
5883 program into a reusable file. If the program you are debugging is
5884 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5885 Future GDB debugging sessions will notice the presence of this file,
5886 and will quickly map in symbol information from it, rather than reading
5887 the symbol table from the executable program. Using the '-mapped'
5888 option in a GDB `file' or `symbol-file' command has the same effect as
5889 starting GDB with the '-mapped' command-line option.
5891 You can cause GDB to read the entire symbol table immediately by using
5892 the '-readnow' option with any of the commands that load symbol table
5893 information (or on the GDB command line). This makes the command
5894 slower, but makes future operations faster.
5896 The -mapped and -readnow options are typically combined in order to
5897 build a `fred.syms' file that contains complete symbol information.
5898 A simple GDB invocation to do nothing but build a `.syms' file for future
5901 gdb -batch -nx -mapped -readnow programname
5903 The `.syms' file is specific to the host machine on which GDB is run.
5904 It holds an exact image of GDB's internal symbol table. It cannot be
5905 shared across multiple host platforms.
5907 * longjmp() handling
5909 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5910 siglongjmp() without losing control. This feature has not yet been ported to
5911 all systems. It currently works on many 386 platforms, all MIPS-based
5912 platforms (SGI, DECstation, etc), and Sun3/4.
5916 Preliminary work has been put in to support the new Solaris OS from Sun. At
5917 this time, it can control and debug processes, but it is not capable of
5922 As always, many many bug fixes. The major areas were with g++, and mipsread.
5923 People using the MIPS-based platforms should experience fewer mysterious
5924 crashes and trashed symbol tables.
5926 *** Changes in GDB-4.4:
5928 * New machines supported (host and target)
5930 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5932 BSD Reno on Vax vax-dec-bsd
5933 Ultrix on Vax vax-dec-ultrix
5935 * New machines supported (target)
5937 AMD 29000 embedded, using EBMON a29k-none-none
5941 GDB continues to improve its handling of C++. `References' work better.
5942 The demangler has also been improved, and now deals with symbols mangled as
5943 per the Annotated C++ Reference Guide.
5945 GDB also now handles `stabs' symbol information embedded in MIPS
5946 `ecoff' symbol tables. Since the ecoff format was not easily
5947 extensible to handle new languages such as C++, this appeared to be a
5948 good way to put C++ debugging info into MIPS binaries. This option
5949 will be supported in the GNU C compiler, version 2, when it is
5952 * New features for SVR4
5954 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5955 shared libraries. Debugging dynamically linked programs should present
5956 only minor differences from debugging statically linked programs.
5958 The `info proc' command will print out information about any process
5959 on an SVR4 system (including the one you are debugging). At the moment,
5960 it prints the address mappings of the process.
5962 If you bring up GDB on another SVR4 system, please send mail to
5963 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5965 * Better dynamic linking support in SunOS
5967 Reading symbols from shared libraries which contain debugging symbols
5968 now works properly. However, there remain issues such as automatic
5969 skipping of `transfer vector' code during function calls, which
5970 make it harder to debug code in a shared library, than to debug the
5971 same code linked statically.
5975 GDB is now using the latest `getopt' routines from the FSF. This
5976 version accepts the -- prefix for options with long names. GDB will
5977 continue to accept the old forms (-option and +option) as well.
5978 Various single letter abbreviations for options have been explicity
5979 added to the option table so that they won't get overshadowed in the
5980 future by other options that begin with the same letter.
5984 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5985 Many assorted bugs have been handled. Many more remain to be handled.
5986 See the various ChangeLog files (primarily in gdb and bfd) for details.
5989 *** Changes in GDB-4.3:
5991 * New machines supported (host and target)
5993 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5994 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5995 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5997 * Almost SCO Unix support
5999 We had hoped to support:
6000 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6001 (except for core file support), but we discovered very late in the release
6002 that it has problems with process groups that render gdb unusable. Sorry
6003 about that. I encourage people to fix it and post the fixes.
6005 * Preliminary ELF and DWARF support
6007 GDB can read ELF object files on System V Release 4, and can handle
6008 debugging records for C, in DWARF format, in ELF files. This support
6009 is preliminary. If you bring up GDB on another SVR4 system, please
6010 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6015 GDB now uses the latest `readline' library. One user-visible change
6016 is that two tabs will list possible command completions, which previously
6017 required typing M-? (meta-question mark, or ESC ?).
6021 The `stepi' bug that many of you noticed has been squashed.
6022 Many bugs in C++ have been handled. Many more remain to be handled.
6023 See the various ChangeLog files (primarily in gdb and bfd) for details.
6025 * State of the MIPS world (in case you wondered):
6027 GDB can understand the symbol tables emitted by the compilers
6028 supplied by most vendors of MIPS-based machines, including DEC. These
6029 symbol tables are in a format that essentially nobody else uses.
6031 Some versions of gcc come with an assembler post-processor called
6032 mips-tfile. This program is required if you want to do source-level
6033 debugging of gcc-compiled programs. I believe FSF does not ship
6034 mips-tfile with gcc version 1, but it will eventually come with gcc
6037 Debugging of g++ output remains a problem. g++ version 1.xx does not
6038 really support it at all. (If you're lucky, you should be able to get
6039 line numbers and stack traces to work, but no parameters or local
6040 variables.) With some work it should be possible to improve the
6043 When gcc version 2 is released, you will have somewhat better luck.
6044 However, even then you will get confusing results for inheritance and
6047 We will eventually provide full debugging of g++ output on
6048 DECstations. This will probably involve some kind of stabs-in-ecoff
6049 encapulation, but the details have not been worked out yet.
6052 *** Changes in GDB-4.2:
6054 * Improved configuration
6056 Only one copy of `configure' exists now, and it is not self-modifying.
6057 Porting BFD is simpler.
6061 The `step' and `next' commands now only stop at the first instruction
6062 of a source line. This prevents the multiple stops that used to occur
6063 in switch statements, for-loops, etc. `Step' continues to stop if a
6064 function that has debugging information is called within the line.
6068 Lots of small bugs fixed. More remain.
6070 * New host supported (not target)
6072 Intel 386 PC clone running Mach i386-none-mach
6075 *** Changes in GDB-4.1:
6077 * Multiple source language support
6079 GDB now has internal scaffolding to handle several source languages.
6080 It determines the type of each source file from its filename extension,
6081 and will switch expression parsing and number formatting to match the
6082 language of the function in the currently selected stack frame.
6083 You can also specifically set the language to be used, with
6084 `set language c' or `set language modula-2'.
6088 GDB now has preliminary support for the GNU Modula-2 compiler,
6089 currently under development at the State University of New York at
6090 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6091 continue through the fall of 1991 and into 1992.
6093 Other Modula-2 compilers are currently not supported, and attempting to
6094 debug programs compiled with them will likely result in an error as the
6095 symbol table is read. Feel free to work on it, though!
6097 There are hooks in GDB for strict type checking and range checking,
6098 in the `Modula-2 philosophy', but they do not currently work.
6102 GDB can now write to executable and core files (e.g. patch
6103 a variable's value). You must turn this switch on, specify
6104 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6105 by assigning a new value to a variable. Modifications take
6108 * Automatic SunOS shared library reading
6110 When you run your program, GDB automatically determines where its
6111 shared libraries (if any) have been loaded, and reads their symbols.
6112 The `share' command is no longer needed. This also works when
6113 examining core files.
6117 You can specify the number of lines that the `list' command shows.
6120 * New machines supported (host and target)
6122 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6123 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6124 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6126 * New hosts supported (not targets)
6128 IBM RT/PC: romp-ibm-aix or rtpc
6130 * New targets supported (not hosts)
6132 AMD 29000 embedded with COFF a29k-none-coff
6133 AMD 29000 embedded with a.out a29k-none-aout
6134 Ultracomputer remote kernel debug a29k-nyu-kern
6136 * New remote interfaces
6142 *** Changes in GDB-4.0:
6146 Wide output is wrapped at good places to make the output more readable.
6148 Gdb now supports cross-debugging from a host machine of one type to a
6149 target machine of another type. Communication with the target system
6150 is over serial lines. The ``target'' command handles connecting to the
6151 remote system; the ``load'' command will download a program into the
6152 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6153 also supports debugging of realtime processes running under VxWorks,
6154 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6155 stub on the target system.
6157 New CPUs supported include the AMD 29000 and Intel 960.
6159 GDB now reads object files and symbol tables via a ``binary file''
6160 library, which allows a single copy of GDB to debug programs of multiple
6161 object file types such as a.out and coff.
6163 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6164 refcard.dvi and refcard.ps are available to format it).
6167 * Control-Variable user interface simplified
6169 All variables that control the operation of the debugger can be set
6170 by the ``set'' command, and displayed by the ``show'' command.
6172 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6173 ``Show prompt'' produces the response:
6174 Gdb's prompt is new-gdb=>.
6176 What follows are the NEW set commands. The command ``help set'' will
6177 print a complete list of old and new set commands. ``help set FOO''
6178 will give a longer description of the variable FOO. ``show'' will show
6179 all of the variable descriptions and their current settings.
6181 confirm on/off: Enables warning questions for operations that are
6182 hard to recover from, e.g. rerunning the program while
6183 it is already running. Default is ON.
6185 editing on/off: Enables EMACS style command line editing
6186 of input. Previous lines can be recalled with
6187 control-P, the current line can be edited with control-B,
6188 you can search for commands with control-R, etc.
6191 history filename NAME: NAME is where the gdb command history
6192 will be stored. The default is .gdb_history,
6193 or the value of the environment variable
6196 history size N: The size, in commands, of the command history. The
6197 default is 256, or the value of the environment variable
6200 history save on/off: If this value is set to ON, the history file will
6201 be saved after exiting gdb. If set to OFF, the
6202 file will not be saved. The default is OFF.
6204 history expansion on/off: If this value is set to ON, then csh-like
6205 history expansion will be performed on
6206 command line input. The default is OFF.
6208 radix N: Sets the default radix for input and output. It can be set
6209 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6210 in the current radix, so "set radix 10" is always a no-op.
6212 height N: This integer value is the number of lines on a page. Default
6213 is 24, the current `stty rows'' setting, or the ``li#''
6214 setting from the termcap entry matching the environment
6217 width N: This integer value is the number of characters on a line.
6218 Default is 80, the current `stty cols'' setting, or the ``co#''
6219 setting from the termcap entry matching the environment
6222 Note: ``set screensize'' is obsolete. Use ``set height'' and
6223 ``set width'' instead.
6225 print address on/off: Print memory addresses in various command displays,
6226 such as stack traces and structure values. Gdb looks
6227 more ``symbolic'' if you turn this off; it looks more
6228 ``machine level'' with it on. Default is ON.
6230 print array on/off: Prettyprint arrays. New convenient format! Default
6233 print demangle on/off: Print C++ symbols in "source" form if on,
6236 print asm-demangle on/off: Same, for assembler level printouts
6239 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6242 * Support for Epoch Environment.
6244 The epoch environment is a version of Emacs v18 with windowing. One
6245 new command, ``inspect'', is identical to ``print'', except that if you
6246 are running in the epoch environment, the value is printed in its own
6250 * Support for Shared Libraries
6252 GDB can now debug programs and core files that use SunOS shared libraries.
6253 Symbols from a shared library cannot be referenced
6254 before the shared library has been linked with the program (this
6255 happens after you type ``run'' and before the function main() is entered).
6256 At any time after this linking (including when examining core files
6257 from dynamically linked programs), gdb reads the symbols from each
6258 shared library when you type the ``sharedlibrary'' command.
6259 It can be abbreviated ``share''.
6261 sharedlibrary REGEXP: Load shared object library symbols for files
6262 matching a unix regular expression. No argument
6263 indicates to load symbols for all shared libraries.
6265 info sharedlibrary: Status of loaded shared libraries.
6270 A watchpoint stops execution of a program whenever the value of an
6271 expression changes. Checking for this slows down execution
6272 tremendously whenever you are in the scope of the expression, but is
6273 quite useful for catching tough ``bit-spreader'' or pointer misuse
6274 problems. Some machines such as the 386 have hardware for doing this
6275 more quickly, and future versions of gdb will use this hardware.
6277 watch EXP: Set a watchpoint (breakpoint) for an expression.
6279 info watchpoints: Information about your watchpoints.
6281 delete N: Deletes watchpoint number N (same as breakpoints).
6282 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6283 enable N: Re-enables watchpoint number N (same as breakpoints).
6286 * C++ multiple inheritance
6288 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6291 * C++ exception handling
6293 Gdb now supports limited C++ exception handling. Besides the existing
6294 ability to breakpoint on an exception handler, gdb can breakpoint on
6295 the raising of an exception (before the stack is peeled back to the
6298 catch FOO: If there is a FOO exception handler in the dynamic scope,
6299 set a breakpoint to catch exceptions which may be raised there.
6300 Multiple exceptions (``catch foo bar baz'') may be caught.
6302 info catch: Lists all exceptions which may be caught in the
6303 current stack frame.
6306 * Minor command changes
6308 The command ``call func (arg, arg, ...)'' now acts like the print
6309 command, except it does not print or save a value if the function's result
6310 is void. This is similar to dbx usage.
6312 The ``up'' and ``down'' commands now always print the frame they end up
6313 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6314 frames without printing.
6316 * New directory command
6318 'dir' now adds directories to the FRONT of the source search path.
6319 The path starts off empty. Source files that contain debug information
6320 about the directory in which they were compiled can be found even
6321 with an empty path; Sun CC and GCC include this information. If GDB can't
6322 find your source file in the current directory, type "dir .".
6324 * Configuring GDB for compilation
6326 For normal use, type ``./configure host''. See README or gdb.texinfo
6329 GDB now handles cross debugging. If you are remotely debugging between
6330 two different machines, type ``./configure host -target=targ''.
6331 Host is the machine where GDB will run; targ is the machine
6332 where the program that you are debugging will run.