1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.10
6 * Per-inferior thread numbers
8 Thread numbers are now per inferior instead of global. If you're
9 debugging multiple inferiors, GDB displays thread IDs using a
10 qualified INF_NUM.THR_NUM form. For example:
14 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
15 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
16 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
17 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
19 As consequence, thread numbers as visible in the $_thread
20 convenience variable and in Python's InferiorThread.num attribute
21 are no longer unique between inferiors.
23 GDB now maintains a second thread ID per thread, referred to as the
24 global thread ID, which is the new equivalent of thread numbers in
27 For backwards compatibility, MI's thread IDs always refer to global
30 * Commands that accept thread IDs now accept the qualified
31 INF_NUM.THR_NUM form as well. For example:
34 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
37 * The new convenience variable $_inferior holds the number of the
40 * Record btrace now supports non-stop mode.
42 * Support for tracepoints on aarch64-linux was added in GDBserver.
44 * The 'record instruction-history' command now indicates speculative execution
45 when using the Intel Processor Trace recording format.
47 * GDB now allows users to specify explicit locations, bypassing
48 the linespec parser. This feature is also available to GDB/MI
51 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
52 GDB now is able to debug both AArch64 applications and ARM applications
55 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
56 including JIT compiling fast tracepoint's conditional expression bytecode
59 * GDB now supports displaced stepping on AArch64 GNU/Linux.
61 * "info threads", "info inferiors", "info display", "info checkpoints"
62 and "maint info program-spaces" now list the corresponding items in
63 ascending ID order, for consistency with all other "info" commands.
65 * In Ada, the overloads selection menu has been enhanced to display the
66 parameter types and the return types for the matching overloaded subprograms.
70 maint set target-non-stop (on|off|auto)
71 maint show target-non-stop
72 Control whether GDB targets always operate in non-stop mode even if
73 "set non-stop" is "off". The default is "auto", meaning non-stop
74 mode is enabled if supported by the target.
77 maint show bfd-sharing
78 Control the reuse of bfd objects.
82 Control display of debugging info regarding bfd caching.
84 set remote multiprocess-extensions-packet
85 show remote multiprocess-extensions-packet
86 Set/show the use of the remote protocol multiprocess extensions.
88 set remote thread-events
89 show remote thread-events
90 Set/show the use of thread create/exit events.
92 set ada print-signatures on|off
93 show ada print-signatures"
94 Control whether parameter types and return types are displayed in overloads
95 selection menus. It is activaled (@code{on}) by default.
97 * The "disassemble" command accepts a new modifier: /s.
98 It prints mixed source+disassembly like /m with two differences:
99 - disassembled instructions are now printed in program order, and
100 - and source for all relevant files is now printed.
101 The "/m" option is now considered deprecated: its "source-centric"
102 output hasn't proved useful in practice.
104 * The "record instruction-history" command accepts a new modifier: /s.
105 It behaves exactly like /m and prints mixed source+disassembly.
107 * The "set scheduler-locking" command supports a new mode "replay".
108 It behaves like "off" in record mode and like "on" in replay mode.
110 * Support for various ROM monitors has been removed:
112 target dbug dBUG ROM monitor for Motorola ColdFire
113 target picobug Motorola picobug monitor
114 target dink32 DINK32 ROM monitor for PowerPC
115 target m32r Renesas M32R/D ROM monitor
116 target mon2000 mon2000 ROM monitor
117 target ppcbug PPCBUG ROM monitor for PowerPC
119 * Support for reading/writing memory and extracting values on architectures
120 whose memory is addressable in units of any integral multiple of 8 bits.
125 Indicates that an exec system call was executed.
127 exec-events feature in qSupported
128 The qSupported packet allows GDB to request support for exec
129 events using the new 'gdbfeature' exec-event, and the qSupported
130 response can contain the corresponding 'stubfeature'. Set and
131 show commands can be used to display whether these features are enabled.
134 Equivalent to interrupting with the ^C character, but works in
137 thread created stop reason (T05 create:...)
138 Indicates that the thread was just created and is stopped at entry.
140 thread exit stop reply (w exitcode;tid)
141 Indicates that the thread has terminated.
144 Enables/disables thread create and exit event reporting. For
145 example, this is used in non-stop mode when GDB stops a set of
146 threads and synchronously waits for the their corresponding stop
147 replies. Without exit events, if one of the threads exits, GDB
148 would hang forever not knowing that it should no longer expect a
149 stop for that same thread.
153 Indicates that there are no resumed threads left in the target (all
154 threads are stopped). The remote stub reports support for this stop
155 reply to GDB's qSupported query.
157 QCatchSyscalls:1 [;SYSNO]...
159 Enable ("QCatchSyscalls:1") or disable ("QCatchSyscalls:0")
160 catching syscalls from the inferior process.
162 syscall_entry stop reason
163 Indicates that a syscall was just called.
165 syscall_return stop reason
166 Indicates that a syscall just returned.
168 QCatchSyscalls:1 in qSupported
169 The qSupported packet may now include QCatchSyscalls:1 in the reply
170 to indicate support for catching syscalls.
172 * Extended-remote exec events
174 ** GDB now has support for exec events on extended-remote Linux targets.
175 For such targets with Linux kernels 2.5.46 and later, this enables
176 follow-exec-mode and exec catchpoints.
178 set remote exec-event-feature-packet
179 show remote exec-event-feature-packet
180 Set/show the use of the remote exec event feature.
182 * Thread names in remote protocol
184 The reply to qXfer:threads:read may now include a name attribute for each
187 * Target remote mode fork and exec events
189 ** GDB now has support for fork and exec events on target remote mode
190 Linux targets. For such targets with Linux kernels 2.5.46 and later,
191 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
192 fork and exec catchpoints.
194 * Remote syscall events
196 ** GDB now has support for catch syscall on remote Linux targets,
197 currently enabled on x86/x86_64 architectures.
199 set remote catch-syscall-packet
200 show remote catch-syscall-packet
201 Set/show the use of the remote catch syscall feature.
205 ** The -var-set-format command now accepts the zero-hexadecimal
206 format. It outputs data in hexadecimal format with zero-padding on the
211 ** The "num" attribute of gdb.InferiorThread objects now refers to
212 the thread's per-inferior number. See "Per-inferior thread
214 ** gdb.InferiorThread objects have a new attribute "inferior", which
215 is the Inferior object the thread belongs to.
217 *** Changes in GDB 7.10
219 * Support for process record-replay and reverse debugging on aarch64*-linux*
220 targets has been added. GDB now supports recording of A64 instruction set
221 including advance SIMD instructions.
223 * Support for Sun's version of the "stabs" debug file format has been removed.
225 * GDB now honors the content of the file /proc/PID/coredump_filter
226 (PID is the process ID) on GNU/Linux systems. This file can be used
227 to specify the types of memory mappings that will be included in a
228 corefile. For more information, please refer to the manual page of
229 "core(5)". GDB also has a new command: "set use-coredump-filter
230 on|off". It allows to set whether GDB will read the content of the
231 /proc/PID/coredump_filter file when generating a corefile.
233 * The "info os" command on GNU/Linux can now display information on
235 "info os cpus" Listing of all cpus/cores on the system
237 * GDB has two new commands: "set serial parity odd|even|none" and
238 "show serial parity". These allows to set or show parity for the
241 * The "info source" command now displays the producer string if it was
242 present in the debug info. This typically includes the compiler version
243 and may include things like its command line arguments.
245 * The "info dll", an alias of the "info sharedlibrary" command,
246 is now available on all platforms.
248 * Directory names supplied to the "set sysroot" commands may be
249 prefixed with "target:" to tell GDB to access shared libraries from
250 the target system, be it local or remote. This replaces the prefix
251 "remote:". The default sysroot has been changed from "" to
252 "target:". "remote:" is automatically converted to "target:" for
253 backward compatibility.
255 * The system root specified by "set sysroot" will be prepended to the
256 filename of the main executable (if reported to GDB as absolute by
257 the operating system) when starting processes remotely, and when
258 attaching to already-running local or remote processes.
260 * GDB now supports automatic location and retrieval of executable
261 files from remote targets. Remote debugging can now be initiated
262 using only a "target remote" or "target extended-remote" command
263 (no "set sysroot" or "file" commands are required). See "New remote
266 * The "dump" command now supports verilog hex format.
268 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
270 * On GNU/Linux, GDB and gdbserver are now able to access executable
271 and shared library files without a "set sysroot" command when
272 attaching to processes running in different mount namespaces from
273 the debugger. This makes it possible to attach to processes in
274 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
275 See "New remote packets" below.
277 * The "tui reg" command now provides completion for all of the
278 available register groups, including target specific groups.
280 * The HISTSIZE environment variable is no longer read when determining
281 the size of GDB's command history. GDB now instead reads the dedicated
282 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
283 disables truncation of command history. Non-numeric values of GDBHISTSIZE
288 ** Memory ports can now be unbuffered.
292 ** gdb.Objfile objects have a new attribute "username",
293 which is the name of the objfile as specified by the user,
294 without, for example, resolving symlinks.
295 ** You can now write frame unwinders in Python.
296 ** gdb.Type objects have a new method "optimized_out",
297 returning optimized out gdb.Value instance of this type.
298 ** gdb.Value objects have new methods "reference_value" and
299 "const_value" which return a reference to the value and a
300 "const" version of the value respectively.
304 maint print symbol-cache
305 Print the contents of the symbol cache.
307 maint print symbol-cache-statistics
308 Print statistics of symbol cache usage.
310 maint flush-symbol-cache
311 Flush the contents of the symbol cache.
315 Start branch trace recording using Branch Trace Store (BTS) format.
318 Evaluate expression by using the compiler and print result.
322 Explicit commands for enabling and disabling tui mode.
325 set mpx bound on i386 and amd64
326 Support for bound table investigation on Intel MPX enabled applications.
330 Start branch trace recording using Intel Processor Trace format.
333 Print information about branch tracing internals.
335 maint btrace packet-history
336 Print the raw branch tracing data.
338 maint btrace clear-packet-history
339 Discard the stored raw branch tracing data.
342 Discard all branch tracing data. It will be fetched and processed
343 anew by the next "record" command.
348 Renamed from "set debug dwarf2-die".
350 Renamed from "show debug dwarf2-die".
353 Renamed from "set debug dwarf2-read".
354 show debug dwarf-read
355 Renamed from "show debug dwarf2-read".
357 maint set dwarf always-disassemble
358 Renamed from "maint set dwarf2 always-disassemble".
359 maint show dwarf always-disassemble
360 Renamed from "maint show dwarf2 always-disassemble".
362 maint set dwarf max-cache-age
363 Renamed from "maint set dwarf2 max-cache-age".
364 maint show dwarf max-cache-age
365 Renamed from "maint show dwarf2 max-cache-age".
368 show debug dwarf-line
369 Control display of debugging info regarding DWARF line processing.
373 Set the maximum number of candidates to be considered during
374 completion. The default value is 200. This limit allows GDB
375 to avoid generating large completion lists, the computation of
376 which can cause the debugger to become temporarily unresponsive.
378 set history remove-duplicates
379 show history remove-duplicates
380 Control the removal of duplicate history entries.
382 maint set symbol-cache-size
383 maint show symbol-cache-size
384 Control the size of the symbol cache.
386 set|show record btrace bts buffer-size
387 Set and show the size of the ring buffer used for branch tracing in
389 The obtained size may differ from the requested size. Use "info
390 record" to see the obtained buffer size.
392 set debug linux-namespaces
393 show debug linux-namespaces
394 Control display of debugging info regarding Linux namespaces.
396 set|show record btrace pt buffer-size
397 Set and show the size of the ring buffer used for branch tracing in
398 Intel Processor Trace format.
399 The obtained size may differ from the requested size. Use "info
400 record" to see the obtained buffer size.
402 maint set|show btrace pt skip-pad
403 Set and show whether PAD packets are skipped when computing the
406 * The command 'thread apply all' can now support new option '-ascending'
407 to call its specified command for all threads in ascending order.
409 * Python/Guile scripting
411 ** GDB now supports auto-loading of Python/Guile scripts contained in the
412 special section named `.debug_gdb_scripts'.
416 qXfer:btrace-conf:read
417 Return the branch trace configuration for the current thread.
419 Qbtrace-conf:bts:size
420 Set the requested ring buffer size for branch tracing in BTS format.
423 Enable Intel Procesor Trace-based branch tracing for the current
424 process. The remote stub reports support for this packet to GDB's
428 Set the requested ring buffer size for branch tracing in Intel Processor
432 Indicates a memory breakpoint instruction was executed, irrespective
433 of whether it was GDB that planted the breakpoint or the breakpoint
434 is hardcoded in the program. This is required for correct non-stop
438 Indicates the target stopped for a hardware breakpoint. This is
439 required for correct non-stop mode operation.
442 Return information about files on the remote system.
445 Return the full absolute name of the file that was executed to
446 create a process running on the remote system.
449 Select the filesystem on which vFile: operations with filename
450 arguments will operate. This is required for GDB to be able to
451 access files on remote targets where the remote stub does not
452 share a common filesystem with the inferior(s).
455 Indicates that a fork system call was executed.
458 Indicates that a vfork system call was executed.
460 vforkdone stop reason
461 Indicates that a vfork child of the specified process has executed
462 an exec or exit, allowing the vfork parent to resume execution.
464 fork-events and vfork-events features in qSupported
465 The qSupported packet allows GDB to request support for fork and
466 vfork events using new 'gdbfeatures' fork-events and vfork-events,
467 and the qSupported response can contain the corresponding
468 'stubfeatures'. Set and show commands can be used to display
469 whether these features are enabled.
471 * Extended-remote fork events
473 ** GDB now has support for fork events on extended-remote Linux
474 targets. For targets with Linux kernels 2.5.60 and later, this
475 enables follow-fork-mode and detach-on-fork for both fork and
476 vfork, as well as fork and vfork catchpoints.
478 * The info record command now shows the recording format and the
479 branch tracing configuration for the current thread when using
480 the btrace record target.
481 For the BTS format, it shows the ring buffer size.
483 * GDB now has support for DTrace USDT (Userland Static Defined
484 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
486 * GDB now supports access to vector registers on S/390 GNU/Linux
489 * Removed command line options
491 -xdb HP-UX XDB compatibility mode.
493 * Removed targets and native configurations
495 HP/PA running HP-UX hppa*-*-hpux*
496 Itanium running HP-UX ia64-*-hpux*
498 * New configure options
501 This configure option allows the user to build GDB with support for
502 Intel Processor Trace (default: auto). This requires libipt.
504 --with-libipt-prefix=PATH
505 Specify the path to the version of libipt that GDB should use.
506 $PATH/include should contain the intel-pt.h header and
507 $PATH/lib should contain the libipt.so library.
509 *** Changes in GDB 7.9.1
513 ** Xmethods can now specify a result type.
515 *** Changes in GDB 7.9
517 * GDB now supports hardware watchpoints on x86 GNU Hurd.
521 ** You can now access frame registers from Python scripts.
522 ** New attribute 'producer' for gdb.Symtab objects.
523 ** gdb.Objfile objects have a new attribute "progspace",
524 which is the gdb.Progspace object of the containing program space.
525 ** gdb.Objfile objects have a new attribute "owner".
526 ** gdb.Objfile objects have a new attribute "build_id",
527 which is the build ID generated when the file was built.
528 ** gdb.Objfile objects have a new method "add_separate_debug_file".
529 ** A new event "gdb.clear_objfiles" has been added, triggered when
530 selecting a new file to debug.
531 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
532 ** New function gdb.lookup_objfile.
534 New events which are triggered when GDB modifies the state of the
537 ** gdb.events.inferior_call_pre: Function call is about to be made.
538 ** gdb.events.inferior_call_post: Function call has just been made.
539 ** gdb.events.memory_changed: A memory location has been altered.
540 ** gdb.events.register_changed: A register has been altered.
542 * New Python-based convenience functions:
544 ** $_caller_is(name [, number_of_frames])
545 ** $_caller_matches(regexp [, number_of_frames])
546 ** $_any_caller_is(name [, number_of_frames])
547 ** $_any_caller_matches(regexp [, number_of_frames])
549 * GDB now supports the compilation and injection of source code into
550 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
551 to compile the source code to object code, and if successful, inject
552 and execute that code within the current context of the inferior.
553 Currently the C language is supported. The commands used to
554 interface with this new feature are:
556 compile code [-raw|-r] [--] [source code]
557 compile file [-raw|-r] filename
561 demangle [-l language] [--] name
562 Demangle "name" in the specified language, or the current language
563 if elided. This command is renamed from the "maint demangle" command.
564 The latter is kept as a no-op to avoid "maint demangle" being interpreted
565 as "maint demangler-warning".
567 queue-signal signal-name-or-number
568 Queue a signal to be delivered to the thread when it is resumed.
570 add-auto-load-scripts-directory directory
571 Add entries to the list of directories from which to load auto-loaded
574 maint print user-registers
575 List all currently available "user" registers.
577 compile code [-r|-raw] [--] [source code]
578 Compile, inject, and execute in the inferior the executable object
579 code produced by compiling the provided source code.
581 compile file [-r|-raw] filename
582 Compile and inject into the inferior the executable object code
583 produced by compiling the source code stored in the filename
586 * On resume, GDB now always passes the signal the program had stopped
587 for to the thread the signal was sent to, even if the user changed
588 threads before resuming. Previously GDB would often (but not
589 always) deliver the signal to the thread that happens to be current
592 * Conversely, the "signal" command now consistently delivers the
593 requested signal to the current thread. GDB now asks for
594 confirmation if the program had stopped for a signal and the user
595 switched threads meanwhile.
597 * "breakpoint always-inserted" modes "off" and "auto" merged.
599 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
600 won't remove breakpoints from the target until all threads stop,
601 even in non-stop mode. The "auto" mode has been removed, and "off"
602 is now the default mode.
606 set debug symbol-lookup
607 show debug symbol-lookup
608 Control display of debugging info regarding symbol lookup.
612 ** The -list-thread-groups command outputs an exit-code field for
613 inferiors that have exited.
617 MIPS SDE mips*-sde*-elf*
621 Support for these obsolete configurations has been removed.
623 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
624 SGI Irix-5.x mips-*-irix5*
625 SGI Irix-6.x mips-*-irix6*
626 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
627 VAX running Ultrix vax-*-ultrix*
629 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
630 and "assf"), have been removed. Use the "sharedlibrary" command, or
631 its alias "share", instead.
633 *** Changes in GDB 7.8
635 * New command line options
638 This is an alias for the --data-directory option.
640 * GDB supports printing and modifying of variable length automatic arrays
641 as specified in ISO C99.
643 * The ARM simulator now supports instruction level tracing
644 with or without disassembly.
648 GDB now has support for scripting using Guile. Whether this is
649 available is determined at configure time.
650 Guile version 2.0 or greater is required.
651 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
653 * New commands (for set/show, see "New options" below)
657 Invoke CODE by passing it to the Guile interpreter.
661 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
663 info auto-load guile-scripts [regexp]
664 Print the list of automatically loaded Guile scripts.
666 * The source command is now capable of sourcing Guile scripts.
667 This feature is dependent on the debugger being built with Guile support.
671 set print symbol-loading (off|brief|full)
672 show print symbol-loading
673 Control whether to print informational messages when loading symbol
674 information for a file. The default is "full", but when debugging
675 programs with large numbers of shared libraries the amount of output
678 set guile print-stack (none|message|full)
679 show guile print-stack
680 Show a stack trace when an error is encountered in a Guile script.
682 set auto-load guile-scripts (on|off)
683 show auto-load guile-scripts
684 Control auto-loading of Guile script files.
686 maint ada set ignore-descriptive-types (on|off)
687 maint ada show ignore-descriptive-types
688 Control whether the debugger should ignore descriptive types in Ada
689 programs. The default is not to ignore the descriptive types. See
690 the user manual for more details on descriptive types and the intended
691 usage of this option.
693 set auto-connect-native-target
695 Control whether GDB is allowed to automatically connect to the
696 native target for the run, attach, etc. commands when not connected
697 to any target yet. See also "target native" below.
699 set record btrace replay-memory-access (read-only|read-write)
700 show record btrace replay-memory-access
701 Control what memory accesses are allowed during replay.
703 maint set target-async (on|off)
704 maint show target-async
705 This controls whether GDB targets operate in synchronous or
706 asynchronous mode. Normally the default is asynchronous, if it is
707 available; but this can be changed to more easily debug problems
708 occurring only in synchronous mode.
710 set mi-async (on|off)
712 Control whether MI asynchronous mode is preferred. This supersedes
713 "set target-async" of previous GDB versions.
715 * "set target-async" is deprecated as a CLI option and is now an alias
716 for "set mi-async" (only puts MI into async mode).
718 * Background execution commands (e.g., "c&", "s&", etc.) are now
719 possible ``out of the box'' if the target supports them. Previously
720 the user would need to explicitly enable the possibility with the
721 "set target-async on" command.
723 * New features in the GDB remote stub, GDBserver
725 ** New option --debug-format=option1[,option2,...] allows one to add
726 additional text to each output. At present only timestamps
727 are supported: --debug-format=timestamps.
728 Timestamps can also be turned on with the
729 "monitor set debug-format timestamps" command from GDB.
731 * The 'record instruction-history' command now starts counting instructions
732 at one. This also affects the instruction ranges reported by the
733 'record function-call-history' command when given the /i modifier.
735 * The command 'record function-call-history' supports a new modifier '/c' to
736 indent the function names based on their call stack depth.
737 The fields for the '/i' and '/l' modifier have been reordered.
738 The source line range is now prefixed with 'at'.
739 The instruction range is now prefixed with 'inst'.
740 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
741 "record instruction-history" and "list" commands.
743 * The ranges given as arguments to the 'record function-call-history' and
744 'record instruction-history' commands are now inclusive.
746 * The btrace record target now supports the 'record goto' command.
747 For locations inside the execution trace, the back trace is computed
748 based on the information stored in the execution trace.
750 * The btrace record target supports limited reverse execution and replay.
751 The target does not record data and therefore does not allow reading
754 * The "catch syscall" command now works on s390*-linux* targets.
756 * The "compare-sections" command is no longer specific to target
757 remote. It now works with all targets.
759 * All native targets are now consistently called "native".
760 Consequently, the "target child", "target GNU", "target djgpp",
761 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
762 commands have been replaced with "target native". The QNX/NTO port
763 leaves the "procfs" target in place and adds a "native" target for
764 consistency with other ports. The impact on users should be minimal
765 as these commands previously either throwed an error, or were
766 no-ops. The target's name is visible in the output of the following
767 commands: "help target", "info target", "info files", "maint print
770 * The "target native" command now connects to the native target. This
771 can be used to launch native programs even when "set
772 auto-connect-native-target" is set to off.
774 * GDB now supports access to Intel MPX registers on GNU/Linux.
776 * Support for Intel AVX-512 registers on GNU/Linux.
777 Support displaying and modifying Intel AVX-512 registers
778 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
782 qXfer:btrace:read's annex
783 The qXfer:btrace:read packet supports a new annex 'delta' to read
784 branch trace incrementally.
788 ** Valid Python operations on gdb.Value objects representing
789 structs/classes invoke the corresponding overloaded operators if
791 ** New `Xmethods' feature in the Python API. Xmethods are
792 additional methods or replacements for existing methods of a C++
793 class. This feature is useful for those cases where a method
794 defined in C++ source code could be inlined or optimized out by
795 the compiler, making it unavailable to GDB.
798 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
800 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
801 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
802 its alias "share", instead.
804 * The commands "set remotebaud" and "show remotebaud" are no longer
805 supported. Use "set serial baud" and "show serial baud" (respectively)
810 ** A new option "-gdb-set mi-async" replaces "-gdb-set
811 target-async". The latter is left as a deprecated alias of the
812 former for backward compatibility. If the target supports it,
813 CLI background execution commands are now always possible by
814 default, independently of whether the frontend stated a
815 preference for asynchronous execution with "-gdb-set mi-async".
816 Previously "-gdb-set target-async off" affected both MI execution
817 commands and CLI execution commands.
819 *** Changes in GDB 7.7
821 * Improved support for process record-replay and reverse debugging on
822 arm*-linux* targets. Support for thumb32 and syscall instruction
823 recording has been added.
825 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
827 * GDB now supports Fission DWP file format version 2.
828 http://gcc.gnu.org/wiki/DebugFission
830 * New convenience function "$_isvoid", to check whether an expression
831 is void. A void expression is an expression where the type of the
832 result is "void". For example, some convenience variables may be
833 "void" when evaluated (e.g., "$_exitcode" before the execution of
834 the program being debugged; or an undefined convenience variable).
835 Another example, when calling a function whose return type is
838 * The "maintenance print objfiles" command now takes an optional regexp.
840 * The "catch syscall" command now works on arm*-linux* targets.
842 * GDB now consistently shows "<not saved>" when printing values of
843 registers the debug info indicates have not been saved in the frame
844 and there's nowhere to retrieve them from
845 (callee-saved/call-clobbered registers):
850 (gdb) info registers rax
853 Before, the former would print "<optimized out>", and the latter
854 "*value not available*".
856 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
861 ** Frame filters and frame decorators have been added.
862 ** Temporary breakpoints are now supported.
863 ** Line tables representation has been added.
864 ** New attribute 'parent_type' for gdb.Field objects.
865 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
866 ** New attribute 'name' for gdb.Type objects.
870 Nios II ELF nios2*-*-elf
871 Nios II GNU/Linux nios2*-*-linux
872 Texas Instruments MSP430 msp430*-*-elf
874 * Removed native configurations
876 Support for these a.out NetBSD and OpenBSD obsolete configurations has
877 been removed. ELF variants of these configurations are kept supported.
879 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
880 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
881 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
882 i[34567]86-*-openbsd3.[0-3]
883 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
884 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
885 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
889 Like "catch throw", but catches a re-thrown exception.
891 Renamed from old "maint check-symtabs".
893 Perform consistency checks on symtabs.
895 Expand symtabs matching an optional regexp.
898 Display the details of GDB configure-time options.
900 maint set|show per-command
901 maint set|show per-command space
902 maint set|show per-command time
903 maint set|show per-command symtab
904 Enable display of per-command gdb resource usage.
906 remove-symbol-file FILENAME
907 remove-symbol-file -a ADDRESS
908 Remove a symbol file added via add-symbol-file. The file to remove
909 can be identified by its filename or by an address that lies within
910 the boundaries of this symbol file in memory.
913 info exceptions REGEXP
914 Display the list of Ada exceptions defined in the program being
915 debugged. If provided, only the exceptions whose names match REGEXP
920 set debug symfile off|on
922 Control display of debugging info regarding reading symbol files and
923 symbol tables within those files
925 set print raw frame-arguments
926 show print raw frame-arguments
927 Set/show whether to print frame arguments in raw mode,
928 disregarding any defined pretty-printers.
930 set remote trace-status-packet
931 show remote trace-status-packet
932 Set/show the use of remote protocol qTStatus packet.
936 Control display of debugging messages related to Nios II targets.
940 Control whether target-assisted range stepping is enabled.
942 set startup-with-shell
943 show startup-with-shell
944 Specifies whether Unix child processes are started via a shell or
949 Use the target memory cache for accesses to the code segment. This
950 improves performance of remote debugging (particularly disassembly).
952 * You can now use a literal value 'unlimited' for options that
953 interpret 0 or -1 as meaning "unlimited". E.g., "set
954 trace-buffer-size unlimited" is now an alias for "set
955 trace-buffer-size -1" and "set height unlimited" is now an alias for
958 * The "set debug symtab-create" debugging option of GDB has been changed to
959 accept a verbosity level. 0 means "off", 1 provides basic debugging
960 output, and values of 2 or greater provides more verbose output.
962 * New command-line options
964 Display the details of GDB configure-time options.
966 * The command 'tsave' can now support new option '-ctf' to save trace
967 buffer in Common Trace Format.
969 * Newly installed $prefix/bin/gcore acts as a shell interface for the
972 * GDB now implements the the C++ 'typeid' operator.
974 * The new convenience variable $_exception holds the exception being
975 thrown or caught at an exception-related catchpoint.
977 * The exception-related catchpoints, like "catch throw", now accept a
978 regular expression which can be used to filter exceptions by type.
980 * The new convenience variable $_exitsignal is automatically set to
981 the terminating signal number when the program being debugged dies
982 due to an uncaught signal.
986 ** All MI commands now accept an optional "--language" option.
987 Support for this feature can be verified by using the "-list-features"
988 command, which should contain "language-option".
990 ** The new command -info-gdb-mi-command allows the user to determine
991 whether a GDB/MI command is supported or not.
993 ** The "^error" result record returned when trying to execute an undefined
994 GDB/MI command now provides a variable named "code" whose content is the
995 "undefined-command" error code. Support for this feature can be verified
996 by using the "-list-features" command, which should contain
997 "undefined-command-error-code".
999 ** The -trace-save MI command can optionally save trace buffer in Common
1002 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1004 ** The command -data-list-register-values now accepts an optional
1005 "--skip-unavailable" option. When used, only the available registers
1008 ** The new command -trace-frame-collected dumps collected variables,
1009 computed expressions, tvars, memory and registers in a traceframe.
1011 ** The commands -stack-list-locals, -stack-list-arguments and
1012 -stack-list-variables now accept an option "--skip-unavailable".
1013 When used, only the available locals or arguments are displayed.
1015 ** The -exec-run command now accepts an optional "--start" option.
1016 When used, the command follows the same semantics as the "start"
1017 command, stopping the program's execution at the start of its
1018 main subprogram. Support for this feature can be verified using
1019 the "-list-features" command, which should contain
1020 "exec-run-start-option".
1022 ** The new commands -catch-assert and -catch-exceptions insert
1023 catchpoints stopping the program when Ada exceptions are raised.
1025 ** The new command -info-ada-exceptions provides the equivalent of
1026 the new "info exceptions" command.
1028 * New system-wide configuration scripts
1029 A GDB installation now provides scripts suitable for use as system-wide
1030 configuration scripts for the following systems:
1034 * GDB now supports target-assigned range stepping with remote targets.
1035 This improves the performance of stepping source lines by reducing
1036 the number of control packets from/to GDB. See "New remote packets"
1039 * GDB now understands the element 'tvar' in the XML traceframe info.
1040 It has the id of the collected trace state variables.
1042 * On S/390 targets that provide the transactional-execution feature,
1043 the program interruption transaction diagnostic block (TDB) is now
1044 represented as a number of additional "registers" in GDB.
1046 * New remote packets
1050 The vCont packet supports a new 'r' action, that tells the remote
1051 stub to step through an address range itself, without GDB
1052 involvemement at each single-step.
1054 qXfer:libraries-svr4:read's annex
1055 The previously unused annex of the qXfer:libraries-svr4:read packet
1056 is now used to support passing an argument list. The remote stub
1057 reports support for this argument list to GDB's qSupported query.
1058 The defined arguments are "start" and "prev", used to reduce work
1059 necessary for library list updating, resulting in significant
1062 * New features in the GDB remote stub, GDBserver
1064 ** GDBserver now supports target-assisted range stepping. Currently
1065 enabled on x86/x86_64 GNU/Linux targets.
1067 ** GDBserver now adds element 'tvar' in the XML in the reply to
1068 'qXfer:traceframe-info:read'. It has the id of the collected
1069 trace state variables.
1071 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1074 * New 'z' formatter for printing and examining memory, this displays the
1075 value as hexadecimal zero padded on the left to the size of the type.
1077 * GDB can now use Windows x64 unwinding data.
1079 * The "set remotebaud" command has been replaced by "set serial baud".
1080 Similarly, "show remotebaud" has been replaced by "show serial baud".
1081 The "set remotebaud" and "show remotebaud" commands are still available
1082 to provide backward compatibility with older versions of GDB.
1084 *** Changes in GDB 7.6
1086 * Target record has been renamed to record-full.
1087 Record/replay is now enabled with the "record full" command.
1088 This also affects settings that are associated with full record/replay
1089 that have been moved from "set/show record" to "set/show record full":
1091 set|show record full insn-number-max
1092 set|show record full stop-at-limit
1093 set|show record full memory-query
1095 * A new record target "record-btrace" has been added. The new target
1096 uses hardware support to record the control-flow of a process. It
1097 does not support replaying the execution, but it implements the
1098 below new commands for investigating the recorded execution log.
1099 This new recording method can be enabled using:
1103 The "record-btrace" target is only available on Intel Atom processors
1104 and requires a Linux kernel 2.6.32 or later.
1106 * Two new commands have been added for record/replay to give information
1107 about the recorded execution without having to replay the execution.
1108 The commands are only supported by "record btrace".
1110 record instruction-history prints the execution history at
1111 instruction granularity
1113 record function-call-history prints the execution history at
1114 function granularity
1116 * New native configurations
1118 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1119 FreeBSD/powerpc powerpc*-*-freebsd
1120 x86_64/Cygwin x86_64-*-cygwin*
1121 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1125 ARM AArch64 aarch64*-*-elf
1126 ARM AArch64 GNU/Linux aarch64*-*-linux
1127 Lynx 178 PowerPC powerpc-*-lynx*178
1128 x86_64/Cygwin x86_64-*-cygwin*
1129 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1131 * If the configured location of system.gdbinit file (as given by the
1132 --with-system-gdbinit option at configure time) is in the
1133 data-directory (as specified by --with-gdb-datadir at configure
1134 time) or in one of its subdirectories, then GDB will look for the
1135 system-wide init file in the directory specified by the
1136 --data-directory command-line option.
1138 * New command line options:
1140 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1141 other initialization files, unlike -nx which disables all of them.
1143 * Removed command line options
1145 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1148 * The 'ptype' and 'whatis' commands now accept an argument to control
1151 * 'info proc' now works on some core files.
1155 ** Vectors can be created with gdb.Type.vector.
1157 ** Python's atexit.register now works in GDB.
1159 ** Types can be pretty-printed via a Python API.
1161 ** Python 3 is now supported (in addition to Python 2.4 or later)
1163 ** New class gdb.Architecture exposes GDB's internal representation
1164 of architecture in the Python API.
1166 ** New method Frame.architecture returns the gdb.Architecture object
1167 corresponding to the frame's architecture.
1169 * New Python-based convenience functions:
1171 ** $_memeq(buf1, buf2, length)
1172 ** $_streq(str1, str2)
1174 ** $_regex(str, regex)
1176 * The 'cd' command now defaults to using '~' (the home directory) if not
1179 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1180 default for GCC since November 2000.
1182 * The command 'forward-search' can now be abbreviated as 'fo'.
1184 * The command 'info tracepoints' can now display 'installed on target'
1185 or 'not installed on target' for each non-pending location of tracepoint.
1187 * New configure options
1189 --enable-libmcheck/--disable-libmcheck
1190 By default, development versions are built with -lmcheck on hosts
1191 that support it, in order to help track memory corruption issues.
1192 Release versions, on the other hand, are built without -lmcheck
1193 by default. The --enable-libmcheck/--disable-libmcheck configure
1194 options allow the user to override that default.
1195 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1196 This configure option allows the user to build GDB with
1197 libbabeltrace using which GDB can read Common Trace Format data.
1199 * New commands (for set/show, see "New options" below)
1202 Catch signals. This is similar to "handle", but allows commands and
1203 conditions to be attached.
1206 List the BFDs known to GDB.
1208 python-interactive [command]
1210 Start a Python interactive prompt, or evaluate the optional command
1211 and print the result of expressions.
1214 "py" is a new alias for "python".
1216 enable type-printer [name]...
1217 disable type-printer [name]...
1218 Enable or disable type printers.
1222 ** For the Renesas Super-H architecture, the "regs" command has been removed
1223 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1228 set print type methods (on|off)
1229 show print type methods
1230 Control whether method declarations are displayed by "ptype".
1231 The default is to show them.
1233 set print type typedefs (on|off)
1234 show print type typedefs
1235 Control whether typedef definitions are displayed by "ptype".
1236 The default is to show them.
1238 set filename-display basename|relative|absolute
1239 show filename-display
1240 Control the way in which filenames is displayed.
1241 The default is "relative", which preserves previous behavior.
1243 set trace-buffer-size
1244 show trace-buffer-size
1245 Request target to change the size of trace buffer.
1247 set remote trace-buffer-size-packet auto|on|off
1248 show remote trace-buffer-size-packet
1249 Control the use of the remote protocol `QTBuffer:size' packet.
1253 Control display of debugging messages related to ARM AArch64.
1256 set debug coff-pe-read
1257 show debug coff-pe-read
1258 Control display of debugging messages related to reading of COFF/PE
1263 Control display of debugging messages related to Mach-O symbols
1266 set debug notification
1267 show debug notification
1268 Control display of debugging info for async remote notification.
1272 ** Command parameter changes are now notified using new async record
1273 "=cmd-param-changed".
1274 ** Trace frame changes caused by command "tfind" are now notified using
1275 new async record "=traceframe-changed".
1276 ** The creation, deletion and modification of trace state variables
1277 are now notified using new async records "=tsv-created",
1278 "=tsv-deleted" and "=tsv-modified".
1279 ** The start and stop of process record are now notified using new
1280 async record "=record-started" and "=record-stopped".
1281 ** Memory changes are now notified using new async record
1283 ** The data-disassemble command response will include a "fullname" field
1284 containing the absolute file name when source has been requested.
1285 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1286 command, to allow pattern filling of memory areas.
1287 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1288 library load/unload events.
1289 ** The response to breakpoint commands and breakpoint async records
1290 includes an "installed" field containing a boolean state about each
1291 non-pending tracepoint location is whether installed on target or not.
1292 ** Output of the "-trace-status" command includes a "trace-file" field
1293 containing the name of the trace file being examined. This field is
1294 optional, and only present when examining a trace file.
1295 ** The "fullname" field is now always present along with the "file" field,
1296 even if the file cannot be found by GDB.
1298 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1299 You must have the LZMA library available when configuring GDB for this
1300 feature to be enabled. For more information, see:
1301 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1303 * New remote packets
1306 Set the size of trace buffer. The remote stub reports support for this
1307 packet to gdb's qSupported query.
1310 Enable Branch Trace Store (BTS)-based branch tracing for the current
1311 thread. The remote stub reports support for this packet to gdb's
1315 Disable branch tracing for the current thread. The remote stub reports
1316 support for this packet to gdb's qSupported query.
1319 Read the traced branches for the current thread. The remote stub
1320 reports support for this packet to gdb's qSupported query.
1322 *** Changes in GDB 7.5
1324 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1325 for more x32 ABI info.
1327 * GDB now supports access to MIPS DSP registers on Linux targets.
1329 * GDB now supports debugging microMIPS binaries.
1331 * The "info os" command on GNU/Linux can now display information on
1332 several new classes of objects managed by the operating system:
1333 "info os procgroups" lists process groups
1334 "info os files" lists file descriptors
1335 "info os sockets" lists internet-domain sockets
1336 "info os shm" lists shared-memory regions
1337 "info os semaphores" lists semaphores
1338 "info os msg" lists message queues
1339 "info os modules" lists loaded kernel modules
1341 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1342 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1343 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1344 options and inspect the probe arguments using the new $_probe_arg family
1345 of convenience variables. You can obtain more information about SystemTap
1346 in <http://sourceware.org/systemtap/>.
1348 * GDB now supports reversible debugging on ARM, it allows you to
1349 debug basic ARM and THUMB instructions, and provides
1350 record/replay support.
1352 * The option "symbol-reloading" has been deleted as it is no longer used.
1356 ** GDB commands implemented in Python can now be put in command class
1359 ** The "maint set python print-stack on|off" is now deleted.
1361 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1362 apply "flag enum"-style pretty-printing to any enum.
1364 ** gdb.lookup_symbol can now work when there is no current frame.
1366 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1367 the source at which the symbol was defined.
1369 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1370 method 'value'. The former indicates whether the symbol needs a
1371 frame in order to compute its value, and the latter computes the
1374 ** A new method 'referenced_value' on gdb.Value objects which can
1375 dereference pointer as well as C++ reference values.
1377 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1378 which return the global and static blocks (as gdb.Block objects),
1379 of the underlying symbol table, respectively.
1381 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1382 object associated with a PC value.
1384 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1385 of the address range occupied by code for the current source line.
1387 * Go language support.
1388 GDB now supports debugging programs written in the Go programming
1391 * GDBserver now supports stdio connections.
1392 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1394 * The binary "gdbtui" can no longer be built or installed.
1395 Use "gdb -tui" instead.
1397 * GDB will now print "flag" enums specially. A flag enum is one where
1398 all the enumerator values have no bits in common when pairwise
1399 "and"ed. When printing a value whose type is a flag enum, GDB will
1400 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1401 (gdb) print (enum E) 3
1404 * The filename part of a linespec will now match trailing components
1405 of a source file name. For example, "break gcc/expr.c:1000" will
1406 now set a breakpoint in build/gcc/expr.c, but not
1407 build/libcpp/expr.c.
1409 * The "info proc" and "generate-core-file" commands will now also
1410 work on remote targets connected to GDBserver on Linux.
1412 * The command "info catch" has been removed. It has been disabled
1413 since December 2007.
1415 * The "catch exception" and "catch assert" commands now accept
1416 a condition at the end of the command, much like the "break"
1417 command does. For instance:
1419 (gdb) catch exception Constraint_Error if Barrier = True
1421 Previously, it was possible to add a condition to such catchpoints,
1422 but it had to be done as a second step, after the catchpoint had been
1423 created, using the "condition" command.
1425 * The "info static-tracepoint-marker" command will now also work on
1426 native Linux targets with in-process agent.
1428 * GDB can now set breakpoints on inlined functions.
1430 * The .gdb_index section has been updated to include symbols for
1431 inlined functions. GDB will ignore older .gdb_index sections by
1432 default, which could cause symbol files to be loaded more slowly
1433 until their .gdb_index sections can be recreated. The new command
1434 "set use-deprecated-index-sections on" will cause GDB to use any older
1435 .gdb_index sections it finds. This will restore performance, but the
1436 ability to set breakpoints on inlined functions will be lost in symbol
1437 files with older .gdb_index sections.
1439 The .gdb_index section has also been updated to record more information
1440 about each symbol. This speeds up the "info variables", "info functions"
1441 and "info types" commands when used with programs having the .gdb_index
1442 section, as well as speeding up debugging with shared libraries using
1443 the .gdb_index section.
1445 * Ada support for GDB/MI Variable Objects has been added.
1447 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1452 ** New command -info-os is the MI equivalent of "info os".
1454 ** Output logs ("set logging" and related) now include MI output.
1458 ** "set use-deprecated-index-sections on|off"
1459 "show use-deprecated-index-sections on|off"
1460 Controls the use of deprecated .gdb_index sections.
1462 ** "catch load" and "catch unload" can be used to stop when a shared
1463 library is loaded or unloaded, respectively.
1465 ** "enable count" can be used to auto-disable a breakpoint after
1468 ** "info vtbl" can be used to show the virtual method tables for
1469 C++ and Java objects.
1471 ** "explore" and its sub commands "explore value" and "explore type"
1472 can be used to recursively explore values and types of
1473 expressions. These commands are available only if GDB is
1474 configured with '--with-python'.
1476 ** "info auto-load" shows status of all kinds of auto-loaded files,
1477 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1478 sequences of commands files, "info auto-load python-scripts"
1479 shows status of auto-loading Python script files,
1480 "info auto-load local-gdbinit" shows status of loading init file
1481 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1482 status of inferior specific thread debugging shared library loading.
1484 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1485 and "show auto-load-scripts" commands have been deprecated, use their
1486 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1487 and "show auto-load python-scripts" counterparts instead.
1489 ** "dprintf location,format,args..." creates a dynamic printf, which
1490 is basically a breakpoint that does a printf and immediately
1491 resumes your program's execution, so it is like a printf that you
1492 can insert dynamically at runtime instead of at compiletime.
1494 ** "set print symbol"
1496 Controls whether GDB attempts to display the symbol, if any,
1497 corresponding to addresses it prints. This defaults to "on", but
1498 you can set it to "off" to restore GDB's previous behavior.
1500 * Deprecated commands
1502 ** For the Renesas Super-H architecture, the "regs" command has been
1503 deprecated, and "info all-registers" should be used instead.
1507 Renesas RL78 rl78-*-elf
1508 HP OpenVMS ia64 ia64-hp-openvms*
1510 * GDBserver supports evaluation of breakpoint conditions. When
1511 support is advertised by GDBserver, GDB may be told to send the
1512 breakpoint conditions in bytecode form to GDBserver. GDBserver
1513 will only report the breakpoint trigger to GDB when its condition
1518 set mips compression
1519 show mips compression
1520 Select the compressed ISA encoding used in functions that have no symbol
1521 information available. The encoding can be set to either of:
1524 and is updated automatically from ELF file flags if available.
1526 set breakpoint condition-evaluation
1527 show breakpoint condition-evaluation
1528 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1529 GDBserver ("target"). Default option "auto" chooses the most efficient
1531 This option can improve debugger efficiency depending on the speed of the
1535 Disable auto-loading globally.
1538 Show auto-loading setting of all kinds of auto-loaded files.
1540 set auto-load gdb-scripts on|off
1541 show auto-load gdb-scripts
1542 Control auto-loading of GDB canned sequences of commands files.
1544 set auto-load python-scripts on|off
1545 show auto-load python-scripts
1546 Control auto-loading of Python script files.
1548 set auto-load local-gdbinit on|off
1549 show auto-load local-gdbinit
1550 Control loading of init file (.gdbinit) from current directory.
1552 set auto-load libthread-db on|off
1553 show auto-load libthread-db
1554 Control auto-loading of inferior specific thread debugging shared library.
1556 set auto-load scripts-directory <dir1>[:<dir2>...]
1557 show auto-load scripts-directory
1558 Set a list of directories from which to load auto-loaded scripts.
1559 Automatically loaded Python scripts and GDB scripts are located in one
1560 of the directories listed by this option.
1561 The delimiter (':' above) may differ according to the host platform.
1563 set auto-load safe-path <dir1>[:<dir2>...]
1564 show auto-load safe-path
1565 Set a list of directories from which it is safe to auto-load files.
1566 The delimiter (':' above) may differ according to the host platform.
1568 set debug auto-load on|off
1569 show debug auto-load
1570 Control display of debugging info for auto-loading the files above.
1572 set dprintf-style gdb|call|agent
1574 Control the way in which a dynamic printf is performed; "gdb"
1575 requests a GDB printf command, while "call" causes dprintf to call a
1576 function in the inferior. "agent" requests that the target agent
1577 (such as GDBserver) do the printing.
1579 set dprintf-function <expr>
1580 show dprintf-function
1581 set dprintf-channel <expr>
1582 show dprintf-channel
1583 Set the function and optional first argument to the call when using
1584 the "call" style of dynamic printf.
1586 set disconnected-dprintf on|off
1587 show disconnected-dprintf
1588 Control whether agent-style dynamic printfs continue to be in effect
1589 after GDB disconnects.
1591 * New configure options
1593 --with-auto-load-dir
1594 Configure default value for the 'set auto-load scripts-directory'
1595 setting above. It defaults to '$debugdir:$datadir/auto-load',
1596 $debugdir representing global debugging info directories (available
1597 via 'show debug-file-directory') and $datadir representing GDB's data
1598 directory (available via 'show data-directory').
1600 --with-auto-load-safe-path
1601 Configure default value for the 'set auto-load safe-path' setting
1602 above. It defaults to the --with-auto-load-dir setting.
1604 --without-auto-load-safe-path
1605 Set 'set auto-load safe-path' to '/', effectively disabling this
1608 * New remote packets
1610 z0/z1 conditional breakpoints extension
1612 The z0/z1 breakpoint insertion packets have been extended to carry
1613 a list of conditional expressions over to the remote stub depending on the
1614 condition evaluation mode. The use of this extension can be controlled
1615 via the "set remote conditional-breakpoints-packet" command.
1619 Specify the signals which the remote stub may pass to the debugged
1620 program without GDB involvement.
1622 * New command line options
1624 --init-command=FILE, -ix Like --command, -x but execute it
1625 before loading inferior.
1626 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1627 execute it before loading inferior.
1629 *** Changes in GDB 7.4
1631 * GDB now handles ambiguous linespecs more consistently; the existing
1632 FILE:LINE support has been expanded to other types of linespecs. A
1633 breakpoint will now be set on all matching locations in all
1634 inferiors, and locations will be added or removed according to
1637 * GDB now allows you to skip uninteresting functions and files when
1638 stepping with the "skip function" and "skip file" commands.
1640 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1641 and "show remote hardware-watchpoint-length-limit". These allows to
1642 set or show the maximum length limit (in bytes) of a remote
1643 target hardware watchpoint.
1645 This allows e.g. to use "unlimited" hardware watchpoints with the
1646 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1647 watchpoints are slower than real hardware watchpoints but are
1648 significantly faster than gdb software watchpoints.
1652 ** The register_pretty_printer function in module gdb.printing now takes
1653 an optional `replace' argument. If True, the new printer replaces any
1656 ** The "maint set python print-stack on|off" command has been
1657 deprecated and will be deleted in GDB 7.5.
1658 A new command: "set python print-stack none|full|message" has
1659 replaced it. Additionally, the default for "print-stack" is
1660 now "message", which just prints the error message without
1663 ** A prompt substitution hook (prompt_hook) is now available to the
1666 ** A new Python module, gdb.prompt has been added to the GDB Python
1667 modules library. This module provides functionality for
1668 escape sequences in prompts (used by set/show
1669 extended-prompt). These escape sequences are replaced by their
1670 corresponding value.
1672 ** Python commands and convenience-functions located in
1673 'data-directory'/python/gdb/command and
1674 'data-directory'/python/gdb/function are now automatically loaded
1677 ** Blocks now provide four new attributes. global_block and
1678 static_block will return the global and static blocks
1679 respectively. is_static and is_global are boolean attributes
1680 that indicate if the block is one of those two types.
1682 ** Symbols now provide the "type" attribute, the type of the symbol.
1684 ** The "gdb.breakpoint" function has been deprecated in favor of
1687 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1688 of a function. This class is based on the "finish" command
1689 available in the CLI.
1691 ** Type objects for struct and union types now allow access to
1692 the fields using standard Python dictionary (mapping) methods.
1693 For example, "some_type['myfield']" now works, as does
1694 "some_type.items()".
1696 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1699 ** A new function, "deep_items" has been added to the gdb.types
1700 module in the GDB Python modules library. This function returns
1701 an iterator over the fields of a struct or union type. Unlike
1702 the standard Python "iteritems" method, it will recursively traverse
1703 any anonymous fields.
1707 ** "*stopped" events can report several new "reason"s, such as
1710 ** Breakpoint changes are now notified using new async records, like
1711 "=breakpoint-modified".
1713 ** New command -ada-task-info.
1715 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1716 $sdir specifies the default system locations of shared libraries.
1717 $pdir specifies the directory where the libpthread used by the application
1720 GDB no longer looks in $sdir and $pdir after it has searched the directories
1721 mentioned in libthread-db-search-path. If you want to search those
1722 directories, they must be specified in libthread-db-search-path.
1723 The default value of libthread-db-search-path on GNU/Linux and Solaris
1724 systems is now "$sdir:$pdir".
1726 $pdir is not supported by gdbserver, it is currently ignored.
1727 $sdir is supported by gdbserver.
1729 * New configure option --with-iconv-bin.
1730 When using the internationalization support like the one in the GNU C
1731 library, GDB will invoke the "iconv" program to get a list of supported
1732 character sets. If this program lives in a non-standard location, one can
1733 use this option to specify where to find it.
1735 * When natively debugging programs on PowerPC BookE processors running
1736 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1737 watchpoints, which specify a mask in addition to an address to watch.
1738 The mask specifies that some bits of an address (the bits which are
1739 reset in the mask) should be ignored when matching the address accessed
1740 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1741 section in the user manual for more details.
1743 * The new option --once causes GDBserver to stop listening for connections once
1744 the first connection is made. The listening port used by GDBserver will
1745 become available after that.
1747 * New commands "info macros" and "alias" have been added.
1749 * New function parameters suffix @entry specifies value of function parameter
1750 at the time the function got called. Entry values are available only since
1756 "!" is now an alias of the "shell" command.
1757 Note that no space is needed between "!" and SHELL COMMAND.
1761 watch EXPRESSION mask MASK_VALUE
1762 The watch command now supports the mask argument which allows creation
1763 of masked watchpoints, if the current architecture supports this feature.
1765 info auto-load-scripts [REGEXP]
1766 This command was formerly named "maintenance print section-scripts".
1767 It is now generally useful and is no longer a maintenance-only command.
1769 info macro [-all] [--] MACRO
1770 The info macro command has new options `-all' and `--'. The first for
1771 printing all definitions of a macro. The second for explicitly specifying
1772 the end of arguments and the beginning of the macro name in case the macro
1773 name starts with a hyphen.
1775 collect[/s] EXPRESSIONS
1776 The tracepoint collect command now takes an optional modifier "/s"
1777 that directs it to dereference pointer-to-character types and
1778 collect the bytes of memory up to a zero byte. The behavior is
1779 similar to what you see when you use the regular print command on a
1780 string. An optional integer following the "/s" sets a bound on the
1781 number of bytes that will be collected.
1784 The trace start command now interprets any supplied arguments as a
1785 note to be recorded with the trace run, with an effect similar to
1786 setting the variable trace-notes.
1789 The trace stop command now interprets any arguments as a note to be
1790 mentioned along with the tstatus report that the trace was stopped
1791 with a command. The effect is similar to setting the variable
1794 * Tracepoints can now be enabled and disabled at any time after a trace
1795 experiment has been started using the standard "enable" and "disable"
1796 commands. It is now possible to start a trace experiment with no enabled
1797 tracepoints; GDB will display a warning, but will allow the experiment to
1798 begin, assuming that tracepoints will be enabled as needed while the trace
1801 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1802 locations with 4-byte instructions, when they were previously
1803 limited to locations with instructions of 5 bytes or longer.
1807 set debug dwarf2-read
1808 show debug dwarf2-read
1809 Turns on or off display of debugging messages related to reading
1810 DWARF debug info. The default is off.
1812 set debug symtab-create
1813 show debug symtab-create
1814 Turns on or off display of debugging messages related to symbol table
1815 creation. The default is off.
1818 show extended-prompt
1819 Set the GDB prompt, and allow escape sequences to be inserted to
1820 display miscellaneous information (see 'help set extended-prompt'
1821 for the list of sequences). This prompt (and any information
1822 accessed through the escape sequences) is updated every time the
1823 prompt is displayed.
1825 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1826 show print entry-values
1827 Set printing of frame argument values at function entry. In some cases
1828 GDB can determine the value of function argument which was passed by the
1829 function caller, even if the value was modified inside the called function.
1831 set debug entry-values
1832 show debug entry-values
1833 Control display of debugging info for determining frame argument values at
1834 function entry and virtual tail call frames.
1836 set basenames-may-differ
1837 show basenames-may-differ
1838 Set whether a source file may have multiple base names.
1839 (A "base name" is the name of a file with the directory part removed.
1840 Example: The base name of "/home/user/hello.c" is "hello.c".)
1841 If set, GDB will canonicalize file names (e.g., expand symlinks)
1842 before comparing them. Canonicalization is an expensive operation,
1843 but it allows the same file be known by more than one base name.
1844 If not set (the default), all source files are assumed to have just
1845 one base name, and gdb will do file name comparisons more efficiently.
1851 Set a user name and notes for the current and any future trace runs.
1852 This is useful for long-running and/or disconnected traces, to
1853 inform others (or yourself) as to who is running the trace, supply
1854 contact information, or otherwise explain what is going on.
1856 set trace-stop-notes
1857 show trace-stop-notes
1858 Set a note attached to the trace run, that is displayed when the
1859 trace has been stopped by a tstop command. This is useful for
1860 instance as an explanation, if you are stopping a trace run that was
1861 started by someone else.
1863 * New remote packets
1867 Dynamically enable a tracepoint in a started trace experiment.
1871 Dynamically disable a tracepoint in a started trace experiment.
1875 Set the user and notes of the trace run.
1879 Query the current status of a tracepoint.
1883 Query the minimum length of instruction at which a fast tracepoint may
1886 * Dcache size (number of lines) and line-size are now runtime-configurable
1887 via "set dcache line" and "set dcache line-size" commands.
1891 Texas Instruments TMS320C6x tic6x-*-*
1895 Renesas RL78 rl78-*-elf
1897 *** Changes in GDB 7.3.1
1899 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1901 *** Changes in GDB 7.3
1903 * GDB has a new command: "thread find [REGEXP]".
1904 It finds the thread id whose name, target id, or thread extra info
1905 matches the given regular expression.
1907 * The "catch syscall" command now works on mips*-linux* targets.
1909 * The -data-disassemble MI command now supports modes 2 and 3 for
1910 dumping the instruction opcodes.
1912 * New command line options
1914 -data-directory DIR Specify DIR as the "data-directory".
1915 This is mostly for testing purposes.
1917 * The "maint set python auto-load on|off" command has been renamed to
1918 "set auto-load-scripts on|off".
1920 * GDB has a new command: "set directories".
1921 It is like the "dir" command except that it replaces the
1922 source path list instead of augmenting it.
1924 * GDB now understands thread names.
1926 On GNU/Linux, "info threads" will display the thread name as set by
1927 prctl or pthread_setname_np.
1929 There is also a new command, "thread name", which can be used to
1930 assign a name internally for GDB to display.
1933 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1934 has been integrated into GDB.
1938 ** The function gdb.Write now accepts an optional keyword 'stream'.
1939 This keyword, when provided, will direct the output to either
1940 stdout, stderr, or GDB's logging output.
1942 ** Parameters can now be be sub-classed in Python, and in particular
1943 you may implement the get_set_doc and get_show_doc functions.
1944 This improves how Parameter set/show documentation is processed
1945 and allows for more dynamic content.
1947 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1948 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1949 have an is_valid method.
1951 ** Breakpoints can now be sub-classed in Python, and in particular
1952 you may implement a 'stop' function that is executed each time
1953 the inferior reaches that breakpoint.
1955 ** New function gdb.lookup_global_symbol looks up a global symbol.
1957 ** GDB values in Python are now callable if the value represents a
1958 function. For example, if 'some_value' represents a function that
1959 takes two integer parameters and returns a value, you can call
1960 that function like so:
1962 result = some_value (10,20)
1964 ** Module gdb.types has been added.
1965 It contains a collection of utilities for working with gdb.Types objects:
1966 get_basic_type, has_field, make_enum_dict.
1968 ** Module gdb.printing has been added.
1969 It contains utilities for writing and registering pretty-printers.
1970 New classes: PrettyPrinter, SubPrettyPrinter,
1971 RegexpCollectionPrettyPrinter.
1972 New function: register_pretty_printer.
1974 ** New commands "info pretty-printers", "enable pretty-printer" and
1975 "disable pretty-printer" have been added.
1977 ** gdb.parameter("directories") is now available.
1979 ** New function gdb.newest_frame returns the newest frame in the
1982 ** The gdb.InferiorThread class has a new "name" attribute. This
1983 holds the thread's name.
1985 ** Python Support for Inferior events.
1986 Python scripts can add observers to be notified of events
1987 occurring in the process being debugged.
1988 The following events are currently supported:
1989 - gdb.events.cont Continue event.
1990 - gdb.events.exited Inferior exited event.
1991 - gdb.events.stop Signal received, and Breakpoint hit events.
1995 ** GDB now puts template parameters in scope when debugging in an
1996 instantiation. For example, if you have:
1998 template<int X> int func (void) { return X; }
2000 then if you step into func<5>, "print X" will show "5". This
2001 feature requires proper debuginfo support from the compiler; it
2002 was added to GCC 4.5.
2004 ** The motion commands "next", "finish", "until", and "advance" now
2005 work better when exceptions are thrown. In particular, GDB will
2006 no longer lose control of the inferior; instead, the GDB will
2007 stop the inferior at the point at which the exception is caught.
2008 This functionality requires a change in the exception handling
2009 code that was introduced in GCC 4.5.
2011 * GDB now follows GCC's rules on accessing volatile objects when
2012 reading or writing target state during expression evaluation.
2013 One notable difference to prior behavior is that "print x = 0"
2014 no longer generates a read of x; the value of the assignment is
2015 now always taken directly from the value being assigned.
2017 * GDB now has some support for using labels in the program's source in
2018 linespecs. For instance, you can use "advance label" to continue
2019 execution to a label.
2021 * GDB now has support for reading and writing a new .gdb_index
2022 section. This section holds a fast index of DWARF debugging
2023 information and can be used to greatly speed up GDB startup and
2024 operation. See the documentation for `save gdb-index' for details.
2026 * The "watch" command now accepts an optional "-location" argument.
2027 When used, this causes GDB to watch the memory referred to by the
2028 expression. Such a watchpoint is never deleted due to it going out
2031 * GDB now supports thread debugging of core dumps on GNU/Linux.
2033 GDB now activates thread debugging using the libthread_db library
2034 when debugging GNU/Linux core dumps, similarly to when debugging
2035 live processes. As a result, when debugging a core dump file, GDB
2036 is now able to display pthread_t ids of threads. For example, "info
2037 threads" shows the same output as when debugging the process when it
2038 was live. In earlier releases, you'd see something like this:
2041 * 1 LWP 6780 main () at main.c:10
2043 While now you see this:
2046 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2048 It is also now possible to inspect TLS variables when debugging core
2051 When debugging a core dump generated on a machine other than the one
2052 used to run GDB, you may need to point GDB at the correct
2053 libthread_db library with the "set libthread-db-search-path"
2054 command. See the user manual for more details on this command.
2056 * When natively debugging programs on PowerPC BookE processors running
2057 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2058 which stop execution of the inferior whenever it executes an instruction
2059 at any address within the specified range. See the "PowerPC Embedded"
2060 section in the user manual for more details.
2062 * New features in the GDB remote stub, GDBserver
2064 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2065 and i686 LynxOS (version 5.x).
2067 ** GDBserver is now supported on Blackfin Linux.
2069 * New native configurations
2071 ia64 HP-UX ia64-*-hpux*
2075 Analog Devices, Inc. Blackfin Processor bfin-*
2077 * Ada task switching is now supported on sparc-elf targets when
2078 debugging a program using the Ravenscar Profile. For more information,
2079 see the "Tasking Support when using the Ravenscar Profile" section
2080 in the GDB user manual.
2082 * Guile support was removed.
2084 * New features in the GNU simulator
2086 ** The --map-info flag lists all known core mappings.
2088 ** CFI flashes may be simulated via the "cfi" device.
2090 *** Changes in GDB 7.2
2092 * Shared library support for remote targets by default
2094 When GDB is configured for a generic, non-OS specific target, like
2095 for example, --target=arm-eabi or one of the many *-*-elf targets,
2096 GDB now queries remote stubs for loaded shared libraries using the
2097 `qXfer:libraries:read' packet. Previously, shared library support
2098 was always disabled for such configurations.
2102 ** Argument Dependent Lookup (ADL)
2104 In C++ ADL lookup directs function search to the namespaces of its
2105 arguments even if the namespace has not been imported.
2115 Here the compiler will search for `foo' in the namespace of 'b'
2116 and find A::foo. GDB now supports this. This construct is commonly
2117 used in the Standard Template Library for operators.
2119 ** Improved User Defined Operator Support
2121 In addition to member operators, GDB now supports lookup of operators
2122 defined in a namespace and imported with a `using' directive, operators
2123 defined in the global scope, operators imported implicitly from an
2124 anonymous namespace, and the ADL operators mentioned in the previous
2126 GDB now also supports proper overload resolution for all the previously
2127 mentioned flavors of operators.
2129 ** static const class members
2131 Printing of static const class members that are initialized in the
2132 class definition has been fixed.
2134 * Windows Thread Information Block access.
2136 On Windows targets, GDB now supports displaying the Windows Thread
2137 Information Block (TIB) structure. This structure is visible either
2138 by using the new command `info w32 thread-information-block' or, by
2139 dereferencing the new convenience variable named `$_tlb', a
2140 thread-specific pointer to the TIB. This feature is also supported
2141 when remote debugging using GDBserver.
2143 * Static tracepoints
2145 Static tracepoints are calls in the user program into a tracing
2146 library. One such library is a port of the LTTng kernel tracer to
2147 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2148 When debugging with GDBserver, GDB now supports combining the GDB
2149 tracepoint machinery with such libraries. For example: the user can
2150 use GDB to probe a static tracepoint marker (a call from the user
2151 program into the tracing library) with the new "strace" command (see
2152 "New commands" below). This creates a "static tracepoint" in the
2153 breakpoint list, that can be manipulated with the same feature set
2154 as fast and regular tracepoints. E.g., collect registers, local and
2155 global variables, collect trace state variables, and define
2156 tracepoint conditions. In addition, the user can collect extra
2157 static tracepoint marker specific data, by collecting the new
2158 $_sdata internal variable. When analyzing the trace buffer, you can
2159 inspect $_sdata like any other variable available to GDB. For more
2160 information, see the "Tracepoints" chapter in GDB user manual. New
2161 remote packets have been defined to support static tracepoints, see
2162 the "New remote packets" section below.
2164 * Better reconstruction of tracepoints after disconnected tracing
2166 GDB will attempt to download the original source form of tracepoint
2167 definitions when starting a trace run, and then will upload these
2168 upon reconnection to the target, resulting in a more accurate
2169 reconstruction of the tracepoints that are in use on the target.
2173 You can now exercise direct control over the ways that GDB can
2174 affect your program. For instance, you can disallow the setting of
2175 breakpoints, so that the program can run continuously (assuming
2176 non-stop mode). In addition, the "observer" variable is available
2177 to switch all of the different controls; in observer mode, GDB
2178 cannot affect the target's behavior at all, which is useful for
2179 tasks like diagnosing live systems in the field.
2181 * The new convenience variable $_thread holds the number of the
2184 * New remote packets
2188 Return the address of the Windows Thread Information Block of a given thread.
2192 In response to several of the tracepoint packets, the target may now
2193 also respond with a number of intermediate `qRelocInsn' request
2194 packets before the final result packet, to have GDB handle
2195 relocating an instruction to execute at a different address. This
2196 is particularly useful for stubs that support fast tracepoints. GDB
2197 reports support for this feature in the qSupported packet.
2201 List static tracepoint markers in the target program.
2205 List static tracepoint markers at a given address in the target
2208 qXfer:statictrace:read
2210 Read the static trace data collected (by a `collect $_sdata'
2211 tracepoint action). The remote stub reports support for this packet
2212 to gdb's qSupported query.
2216 Send the current settings of GDB's permission flags.
2220 Send part of the source (textual) form of a tracepoint definition,
2221 which includes location, conditional, and action list.
2223 * The source command now accepts a -s option to force searching for the
2224 script in the source search path even if the script name specifies
2227 * New features in the GDB remote stub, GDBserver
2229 - GDBserver now support tracepoints (including fast tracepoints, and
2230 static tracepoints). The feature is currently supported by the
2231 i386-linux and amd64-linux builds. See the "Tracepoints support
2232 in gdbserver" section in the manual for more information.
2234 GDBserver JIT compiles the tracepoint's conditional agent
2235 expression bytecode into native code whenever possible for low
2236 overhead dynamic tracepoints conditionals. For such tracepoints,
2237 an expression that examines program state is evaluated when the
2238 tracepoint is reached, in order to determine whether to capture
2239 trace data. If the condition is simple and false, processing the
2240 tracepoint finishes very quickly and no data is gathered.
2242 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2243 for static tracepoints support.
2245 - GDBserver now supports x86_64 Windows 64-bit debugging.
2247 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2248 it understands register description.
2250 * The --batch flag now disables pagination and queries.
2252 * X86 general purpose registers
2254 GDB now supports reading/writing byte, word and double-word x86
2255 general purpose registers directly. This means you can use, say,
2256 $ah or $ax to refer, respectively, to the byte register AH and
2257 16-bit word register AX that are actually portions of the 32-bit
2258 register EAX or 64-bit register RAX.
2260 * The `commands' command now accepts a range of breakpoints to modify.
2261 A plain `commands' following a command that creates multiple
2262 breakpoints affects all the breakpoints set by that command. This
2263 applies to breakpoints set by `rbreak', and also applies when a
2264 single `break' command creates multiple breakpoints (e.g.,
2265 breakpoints on overloaded c++ functions).
2267 * The `rbreak' command now accepts a filename specification as part of
2268 its argument, limiting the functions selected by the regex to those
2269 in the specified file.
2271 * Support for remote debugging Windows and SymbianOS shared libraries
2272 from Unix hosts has been improved. Non Windows GDB builds now can
2273 understand target reported file names that follow MS-DOS based file
2274 system semantics, such as file names that include drive letters and
2275 use the backslash character as directory separator. This makes it
2276 possible to transparently use the "set sysroot" and "set
2277 solib-search-path" on Unix hosts to point as host copies of the
2278 target's shared libraries. See the new command "set
2279 target-file-system-kind" described below, and the "Commands to
2280 specify files" section in the user manual for more information.
2284 eval template, expressions...
2285 Convert the values of one or more expressions under the control
2286 of the string template to a command line, and call it.
2288 set target-file-system-kind unix|dos-based|auto
2289 show target-file-system-kind
2290 Set or show the assumed file system kind for target reported file
2293 save breakpoints <filename>
2294 Save all current breakpoint definitions to a file suitable for use
2295 in a later debugging session. To read the saved breakpoint
2296 definitions, use the `source' command.
2298 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2301 info static-tracepoint-markers
2302 Display information about static tracepoint markers in the target.
2304 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2305 Define a static tracepoint by probing a marker at the given
2306 function, line, address, or marker ID.
2310 Enable and disable observer mode.
2312 set may-write-registers on|off
2313 set may-write-memory on|off
2314 set may-insert-breakpoints on|off
2315 set may-insert-tracepoints on|off
2316 set may-insert-fast-tracepoints on|off
2317 set may-interrupt on|off
2318 Set individual permissions for GDB effects on the target. Note that
2319 some of these settings can have undesirable or surprising
2320 consequences, particularly when changed in the middle of a session.
2321 For instance, disabling the writing of memory can prevent
2322 breakpoints from being inserted, cause single-stepping to fail, or
2323 even crash your program, if you disable after breakpoints have been
2324 inserted. However, GDB should not crash.
2326 set record memory-query on|off
2327 show record memory-query
2328 Control whether to stop the inferior if memory changes caused
2329 by an instruction cannot be recorded.
2334 The disassemble command now supports "start,+length" form of two arguments.
2338 ** GDB now provides a new directory location, called the python directory,
2339 where Python scripts written for GDB can be installed. The location
2340 of that directory is <data-directory>/python, where <data-directory>
2341 is the GDB data directory. For more details, see section `Scripting
2342 GDB using Python' in the manual.
2344 ** The GDB Python API now has access to breakpoints, symbols, symbol
2345 tables, program spaces, inferiors, threads and frame's code blocks.
2346 Additionally, GDB Parameters can now be created from the API, and
2347 manipulated via set/show in the CLI.
2349 ** New functions gdb.target_charset, gdb.target_wide_charset,
2350 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2352 ** New exception gdb.GdbError.
2354 ** Pretty-printers are now also looked up in the current program space.
2356 ** Pretty-printers can now be individually enabled and disabled.
2358 ** GDB now looks for names of Python scripts to auto-load in a
2359 special section named `.debug_gdb_scripts', in addition to looking
2360 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2362 * Tracepoint actions were unified with breakpoint commands. In particular,
2363 there are no longer differences in "info break" output for breakpoints and
2364 tracepoints and the "commands" command can be used for both tracepoints and
2365 regular breakpoints.
2369 ARM Symbian arm*-*-symbianelf*
2371 * D language support.
2372 GDB now supports debugging programs written in the D programming
2375 * GDB now supports the extended ptrace interface for PowerPC which is
2376 available since Linux kernel version 2.6.34. This automatically enables
2377 any hardware breakpoints and additional hardware watchpoints available in
2378 the processor. The old ptrace interface exposes just one hardware
2379 watchpoint and no hardware breakpoints.
2381 * GDB is now able to use the Data Value Compare (DVC) register available on
2382 embedded PowerPC processors to implement in hardware simple watchpoint
2383 conditions of the form:
2385 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2387 This works in native GDB running on Linux kernels with the extended ptrace
2388 interface mentioned above.
2390 *** Changes in GDB 7.1
2394 ** Namespace Support
2396 GDB now supports importing of namespaces in C++. This enables the
2397 user to inspect variables from imported namespaces. Support for
2398 namepace aliasing has also been added. So, if a namespace is
2399 aliased in the current scope (e.g. namepace C=A; ) the user can
2400 print variables using the alias (e.g. (gdb) print C::x).
2404 All known bugs relating to the printing of virtual base class were
2405 fixed. It is now possible to call overloaded static methods using a
2410 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2411 and reinterpret_cast<> are now handled by the C++ expression parser.
2415 Xilinx MicroBlaze microblaze-*-*
2420 Xilinx MicroBlaze microblaze
2423 * Multi-program debugging.
2425 GDB now has support for multi-program (a.k.a. multi-executable or
2426 multi-exec) debugging. This allows for debugging multiple inferiors
2427 simultaneously each running a different program under the same GDB
2428 session. See "Debugging Multiple Inferiors and Programs" in the
2429 manual for more information. This implied some user visible changes
2430 in the multi-inferior support. For example, "info inferiors" now
2431 lists inferiors that are not running yet or that have exited
2432 already. See also "New commands" and "New options" below.
2434 * New tracing features
2436 GDB's tracepoint facility now includes several new features:
2438 ** Trace state variables
2440 GDB tracepoints now include support for trace state variables, which
2441 are variables managed by the target agent during a tracing
2442 experiment. They are useful for tracepoints that trigger each
2443 other, so for instance one tracepoint can count hits in a variable,
2444 and then a second tracepoint has a condition that is true when the
2445 count reaches a particular value. Trace state variables share the
2446 $-syntax of GDB convenience variables, and can appear in both
2447 tracepoint actions and condition expressions. Use the "tvariable"
2448 command to create, and "info tvariables" to view; see "Trace State
2449 Variables" in the manual for more detail.
2453 GDB now includes an option for defining fast tracepoints, which
2454 targets may implement more efficiently, such as by installing a jump
2455 into the target agent rather than a trap instruction. The resulting
2456 speedup can be by two orders of magnitude or more, although the
2457 tradeoff is that some program locations on some target architectures
2458 might not allow fast tracepoint installation, for instance if the
2459 instruction to be replaced is shorter than the jump. To request a
2460 fast tracepoint, use the "ftrace" command, with syntax identical to
2461 the regular trace command.
2463 ** Disconnected tracing
2465 It is now possible to detach GDB from the target while it is running
2466 a trace experiment, then reconnect later to see how the experiment
2467 is going. In addition, a new variable disconnected-tracing lets you
2468 tell the target agent whether to continue running a trace if the
2469 connection is lost unexpectedly.
2473 GDB now has the ability to save the trace buffer into a file, and
2474 then use that file as a target, similarly to you can do with
2475 corefiles. You can select trace frames, print data that was
2476 collected in them, and use tstatus to display the state of the
2477 tracing run at the moment that it was saved. To create a trace
2478 file, use "tsave <filename>", and to use it, do "target tfile
2481 ** Circular trace buffer
2483 You can ask the target agent to handle the trace buffer as a
2484 circular buffer, discarding the oldest trace frames to make room for
2485 newer ones, by setting circular-trace-buffer to on. This feature may
2486 not be available for all target agents.
2491 The disassemble command, when invoked with two arguments, now requires
2492 the arguments to be comma-separated.
2495 The info variables command now displays variable definitions. Files
2496 which only declare a variable are not shown.
2499 The source command is now capable of sourcing Python scripts.
2500 This feature is dependent on the debugger being build with Python
2503 Related to this enhancement is also the introduction of a new command
2504 "set script-extension" (see below).
2506 * New commands (for set/show, see "New options" below)
2508 record save [<FILENAME>]
2509 Save a file (in core file format) containing the process record
2510 execution log for replay debugging at a later time.
2512 record restore <FILENAME>
2513 Restore the process record execution log that was saved at an
2514 earlier time, for replay debugging.
2516 add-inferior [-copies <N>] [-exec <FILENAME>]
2519 clone-inferior [-copies <N>] [ID]
2520 Make a new inferior ready to execute the same program another
2521 inferior has loaded.
2526 maint info program-spaces
2527 List the program spaces loaded into GDB.
2529 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2530 show remote interrupt-sequence
2531 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2532 as the sequence to the remote target in order to interrupt the execution.
2533 Ctrl-C is a default. Some system prefers BREAK which is high level of
2534 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2535 Magic SysRq g. It is BREAK signal and character 'g'.
2537 set remote interrupt-on-connect [on | off]
2538 show remote interrupt-on-connect
2539 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2540 remote target when gdb connects to it. This is needed when you debug
2543 set remotebreak [on | off]
2545 Deprecated. Use "set/show remote interrupt-sequence" instead.
2547 tvariable $NAME [ = EXP ]
2548 Create or modify a trace state variable.
2551 List trace state variables and their values.
2553 delete tvariable $NAME ...
2554 Delete one or more trace state variables.
2557 Evaluate the given expressions without collecting anything into the
2558 trace buffer. (Valid in tracepoint actions only.)
2560 ftrace FN / FILE:LINE / *ADDR
2561 Define a fast tracepoint at the given function, line, or address.
2563 * New expression syntax
2565 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2566 GDB now parses 0b101010 identically with 42.
2570 set follow-exec-mode new|same
2571 show follow-exec-mode
2572 Control whether GDB reuses the same inferior across an exec call or
2573 creates a new one. This is useful to be able to restart the old
2574 executable after the inferior having done an exec call.
2576 set default-collect EXPR, ...
2577 show default-collect
2578 Define a list of expressions to be collected at each tracepoint.
2579 This is a useful way to ensure essential items are not overlooked,
2580 such as registers or a critical global variable.
2582 set disconnected-tracing
2583 show disconnected-tracing
2584 If set to 1, the target is instructed to continue tracing if it
2585 loses its connection to GDB. If 0, the target is to stop tracing
2588 set circular-trace-buffer
2589 show circular-trace-buffer
2590 If set to on, the target is instructed to use a circular trace buffer
2591 and discard the oldest trace frames instead of stopping the trace due
2592 to a full trace buffer. If set to off, the trace stops when the buffer
2593 fills up. Some targets may not support this.
2595 set script-extension off|soft|strict
2596 show script-extension
2597 If set to "off", the debugger does not perform any script language
2598 recognition, and all sourced files are assumed to be GDB scripts.
2599 If set to "soft" (the default), files are sourced according to
2600 filename extension, falling back to GDB scripts if the first
2602 If set to "strict", files are sourced according to filename extension.
2604 set ada trust-PAD-over-XVS on|off
2605 show ada trust-PAD-over-XVS
2606 If off, activate a workaround against a bug in the debugging information
2607 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2608 the GCC sources for more information about the GNAT encoding and
2609 PAD types in particular). It is always safe to set this option to
2610 off, but this introduces a slight performance penalty. The default
2613 * Python API Improvements
2615 ** GDB provides the new class gdb.LazyString. This is useful in
2616 some pretty-printing cases. The new method gdb.Value.lazy_string
2617 provides a simple way to create objects of this type.
2619 ** The fields returned by gdb.Type.fields now have an
2620 `is_base_class' attribute.
2622 ** The new method gdb.Type.range returns the range of an array type.
2624 ** The new method gdb.parse_and_eval can be used to parse and
2625 evaluate an expression.
2627 * New remote packets
2630 Define a trace state variable.
2633 Get the current value of a trace state variable.
2636 Set desired tracing behavior upon disconnection.
2639 Set the trace buffer to be linear or circular.
2642 Get data about the tracepoints currently in use.
2646 Process record now works correctly with hardware watchpoints.
2648 Multiple bug fixes have been made to the mips-irix port, making it
2649 much more reliable. In particular:
2650 - Debugging threaded applications is now possible again. Previously,
2651 GDB would hang while starting the program, or while waiting for
2652 the program to stop at a breakpoint.
2653 - Attaching to a running process no longer hangs.
2654 - An error occurring while loading a core file has been fixed.
2655 - Changing the value of the PC register now works again. This fixes
2656 problems observed when using the "jump" command, or when calling
2657 a function from GDB, or even when assigning a new value to $pc.
2658 - With the "finish" and "return" commands, the return value for functions
2659 returning a small array is now correctly printed.
2660 - It is now possible to break on shared library code which gets executed
2661 during a shared library init phase (code executed while executing
2662 their .init section). Previously, the breakpoint would have no effect.
2663 - GDB is now able to backtrace through the signal handler for
2664 non-threaded programs.
2666 PIE (Position Independent Executable) programs debugging is now supported.
2667 This includes debugging execution of PIC (Position Independent Code) shared
2668 libraries although for that, it should be possible to run such libraries as an
2671 *** Changes in GDB 7.0
2673 * GDB now has an interface for JIT compilation. Applications that
2674 dynamically generate code can create symbol files in memory and register
2675 them with GDB. For users, the feature should work transparently, and
2676 for JIT developers, the interface is documented in the GDB manual in the
2677 "JIT Compilation Interface" chapter.
2679 * Tracepoints may now be conditional. The syntax is as for
2680 breakpoints; either an "if" clause appended to the "trace" command,
2681 or the "condition" command is available. GDB sends the condition to
2682 the target for evaluation using the same bytecode format as is used
2683 for tracepoint actions.
2685 * The disassemble command now supports: an optional /r modifier, print the
2686 raw instructions in hex as well as in symbolic form, and an optional /m
2687 modifier to print mixed source+assembly.
2689 * Process record and replay
2691 In a architecture environment that supports ``process record and
2692 replay'', ``process record and replay'' target can record a log of
2693 the process execution, and replay it with both forward and reverse
2696 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2697 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2698 set execution-direction {forward|reverse}, for targets that support
2701 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2702 feature is available with a native GDB running on kernel version
2705 * GDB now has support for multi-byte and wide character sets on the
2706 target. Strings whose character type is wchar_t, char16_t, or
2707 char32_t are now correctly printed. GDB supports wide- and unicode-
2708 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2709 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2710 `printf'. This feature requires iconv to work properly; if your
2711 system does not have a working iconv, GDB can use GNU libiconv. See
2712 the installation instructions for more information.
2714 * GDB now supports automatic retrieval of shared library files from
2715 remote targets. To use this feature, specify a system root that begins
2716 with the `remote:' prefix, either via the `set sysroot' command or via
2717 the `--with-sysroot' configure-time option.
2719 * "info sharedlibrary" now takes an optional regex of libraries to show,
2720 and it now reports if a shared library has no debugging information.
2722 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2723 now complete on file names.
2725 * When completing in expressions, gdb will attempt to limit
2726 completions to allowable structure or union fields, where appropriate.
2727 For instance, consider:
2729 # struct example { int f1; double f2; };
2730 # struct example variable;
2733 If the user types TAB at the end of this command line, the available
2734 completions will be "f1" and "f2".
2736 * Inlined functions are now supported. They show up in backtraces, and
2737 the "step", "next", and "finish" commands handle them automatically.
2739 * GDB now supports the token-splicing (##) and stringification (#)
2740 operators when expanding macros. It also supports variable-arity
2743 * GDB now supports inspecting extra signal information, exported by
2744 the new $_siginfo convenience variable. The feature is currently
2745 implemented on linux ARM, i386 and amd64.
2747 * GDB can now display the VFP floating point registers and NEON vector
2748 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2749 can provide these registers (requires Linux 2.6.30 or later). Remote
2750 and simulator targets may also provide them.
2752 * New remote packets
2755 Search memory for a sequence of bytes.
2758 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2759 operation over reliable transport links. Use of this packet is
2760 controlled by the `set remote noack-packet' command.
2763 Kill the process with the specified process ID. Use this in preference
2764 to `k' when multiprocess protocol extensions are supported.
2767 Obtains additional operating system information
2771 Read or write additional signal information.
2773 * Removed remote protocol undocumented extension
2775 An undocumented extension to the remote protocol's `S' stop reply
2776 packet that permited the stub to pass a process id was removed.
2777 Remote servers should use the `T' stop reply packet instead.
2779 * GDB now supports multiple function calling conventions according to the
2780 DWARF-2 DW_AT_calling_convention function attribute.
2782 * The SH target utilizes the aforementioned change to distinguish between gcc
2783 and Renesas calling convention. It also adds the new CLI commands
2784 `set/show sh calling-convention'.
2786 * GDB can now read compressed debug sections, as produced by GNU gold
2787 with the --compress-debug-sections=zlib flag.
2789 * 64-bit core files are now supported on AIX.
2791 * Thread switching is now supported on Tru64.
2793 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2794 which will be allocated using malloc later in program execution.
2796 * The qXfer:libraries:read remote procotol packet now allows passing a
2797 list of section offsets.
2799 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2800 conditions handling signals delivered during attach or thread creation
2801 have also been fixed.
2803 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2804 From the user's standpoint, all unqualified instances of True and False
2805 are treated as the standard definitions, regardless of context.
2807 * GDB now parses C++ symbol and type names more flexibly. For
2810 template<typename T> class C { };
2813 GDB will now correctly handle all of:
2815 ptype C<char const *>
2816 ptype C<char const*>
2817 ptype C<const char *>
2818 ptype C<const char*>
2820 * New features in the GDB remote stub, gdbserver
2822 - The "--wrapper" command-line argument tells gdbserver to use a
2823 wrapper program to launch programs for debugging.
2825 - On PowerPC and S/390 targets, it is now possible to use a single
2826 gdbserver executable to debug both 32-bit and 64-bit programs.
2827 (This requires gdbserver itself to be built as a 64-bit executable.)
2829 - gdbserver uses the new noack protocol mode for TCP connections to
2830 reduce communications latency, if also supported and enabled in GDB.
2832 - Support for the sparc64-linux-gnu target is now included in
2835 - The amd64-linux build of gdbserver now supports debugging both
2836 32-bit and 64-bit programs.
2838 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2839 now support hardware watchpoints, and will use them automatically
2844 GDB now has support for scripting using Python. Whether this is
2845 available is determined at configure time.
2847 New GDB commands can now be written in Python.
2849 * Ada tasking support
2851 Ada tasks can now be inspected in GDB. The following commands have
2855 Print the list of Ada tasks.
2857 Print detailed information about task number N.
2859 Print the task number of the current task.
2861 Switch the context of debugging to task number N.
2863 * Support for user-defined prefixed commands. The "define" command can
2864 add new commands to existing prefixes, e.g. "target".
2866 * Multi-inferior, multi-process debugging.
2868 GDB now has generalized support for multi-inferior debugging. See
2869 "Debugging Multiple Inferiors" in the manual for more information.
2870 Although availability still depends on target support, the command
2871 set is more uniform now. The GNU/Linux specific multi-forks support
2872 has been migrated to this new framework. This implied some user
2873 visible changes; see "New commands" and also "Removed commands"
2876 * Target descriptions can now describe the target OS ABI. See the
2877 "Target Description Format" section in the user manual for more
2880 * Target descriptions can now describe "compatible" architectures
2881 to indicate that the target can execute applications for a different
2882 architecture in addition to those for the main target architecture.
2883 See the "Target Description Format" section in the user manual for
2886 * Multi-architecture debugging.
2888 GDB now includes general supports for debugging applications on
2889 hybrid systems that use more than one single processor architecture
2890 at the same time. Each such hybrid architecture still requires
2891 specific support to be added. The only hybrid architecture supported
2892 in this version of GDB is the Cell Broadband Engine.
2894 * GDB now supports integrated debugging of Cell/B.E. applications that
2895 use both the PPU and SPU architectures. To enable support for hybrid
2896 Cell/B.E. debugging, you need to configure GDB to support both the
2897 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2898 --enable-targets configure option.
2900 * Non-stop mode debugging.
2902 For some targets, GDB now supports an optional mode of operation in
2903 which you can examine stopped threads while other threads continue
2904 to execute freely. This is referred to as non-stop mode, with the
2905 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2906 section in the user manual for more information.
2908 To be able to support remote non-stop debugging, a remote stub needs
2909 to implement the non-stop mode remote protocol extensions, as
2910 described in the "Remote Non-Stop" section of the user manual. The
2911 GDB remote stub, gdbserver, has been adjusted to support these
2912 extensions on linux targets.
2914 * New commands (for set/show, see "New options" below)
2916 catch syscall [NAME(S) | NUMBER(S)]
2917 Catch system calls. Arguments, which should be names of system
2918 calls or their numbers, mean catch only those syscalls. Without
2919 arguments, every syscall will be caught. When the inferior issues
2920 any of the specified syscalls, GDB will stop and announce the system
2921 call, both when it is called and when its call returns. This
2922 feature is currently available with a native GDB running on the
2923 Linux Kernel, under the following architectures: x86, x86_64,
2924 PowerPC and PowerPC64.
2926 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2928 Search memory for a sequence of bytes.
2930 maint set python print-stack
2931 maint show python print-stack
2932 Show a stack trace when an error is encountered in a Python script.
2935 Invoke CODE by passing it to the Python interpreter.
2940 These allow macros to be defined, undefined, and listed
2944 Show operating system information about processes.
2947 List the inferiors currently under GDB's control.
2950 Switch focus to inferior number NUM.
2953 Detach from inferior number NUM.
2956 Kill inferior number NUM.
2960 set spu stop-on-load
2961 show spu stop-on-load
2962 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2964 set spu auto-flush-cache
2965 show spu auto-flush-cache
2966 Control whether to automatically flush the software-managed cache
2967 during Cell/B.E. debugging.
2969 set sh calling-convention
2970 show sh calling-convention
2971 Control the calling convention used when calling SH target functions.
2974 show debug timestamp
2975 Control display of timestamps with GDB debugging output.
2977 set disassemble-next-line
2978 show disassemble-next-line
2979 Control display of disassembled source lines or instructions when
2982 set remote noack-packet
2983 show remote noack-packet
2984 Set/show the use of remote protocol QStartNoAckMode packet. See above
2985 under "New remote packets."
2987 set remote query-attached-packet
2988 show remote query-attached-packet
2989 Control use of remote protocol `qAttached' (query-attached) packet.
2991 set remote read-siginfo-object
2992 show remote read-siginfo-object
2993 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2996 set remote write-siginfo-object
2997 show remote write-siginfo-object
2998 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3001 set remote reverse-continue
3002 show remote reverse-continue
3003 Control use of remote protocol 'bc' (reverse-continue) packet.
3005 set remote reverse-step
3006 show remote reverse-step
3007 Control use of remote protocol 'bs' (reverse-step) packet.
3009 set displaced-stepping
3010 show displaced-stepping
3011 Control displaced stepping mode. Displaced stepping is a way to
3012 single-step over breakpoints without removing them from the debuggee.
3013 Also known as "out-of-line single-stepping".
3016 show debug displaced
3017 Control display of debugging info for displaced stepping.
3019 maint set internal-error
3020 maint show internal-error
3021 Control what GDB does when an internal error is detected.
3023 maint set internal-warning
3024 maint show internal-warning
3025 Control what GDB does when an internal warning is detected.
3030 Use a wrapper program to launch programs for debugging.
3032 set multiple-symbols (all|ask|cancel)
3033 show multiple-symbols
3034 The value of this variable can be changed to adjust the debugger behavior
3035 when an expression or a breakpoint location contains an ambiguous symbol
3036 name (an overloaded function name, for instance).
3038 set breakpoint always-inserted
3039 show breakpoint always-inserted
3040 Keep breakpoints always inserted in the target, as opposed to inserting
3041 them when resuming the target, and removing them when the target stops.
3042 This option can improve debugger performance on slow remote targets.
3044 set arm fallback-mode (arm|thumb|auto)
3045 show arm fallback-mode
3046 set arm force-mode (arm|thumb|auto)
3048 These commands control how ARM GDB determines whether instructions
3049 are ARM or Thumb. The default for both settings is auto, which uses
3050 the current CPSR value for instructions without symbols; previous
3051 versions of GDB behaved as if "set arm fallback-mode arm".
3053 set disable-randomization
3054 show disable-randomization
3055 Standalone programs run with the virtual address space randomization enabled
3056 by default on some platforms. This option keeps the addresses stable across
3057 multiple debugging sessions.
3061 Control whether other threads are stopped or not when some thread hits
3066 Requests that asynchronous execution is enabled in the target, if available.
3067 In this case, it's possible to resume target in the background, and interact
3068 with GDB while the target is running. "show target-async" displays the
3069 current state of asynchronous execution of the target.
3071 set target-wide-charset
3072 show target-wide-charset
3073 The target-wide-charset is the name of the character set that GDB
3074 uses when printing characters whose type is wchar_t.
3076 set tcp auto-retry (on|off)
3078 set tcp connect-timeout
3079 show tcp connect-timeout
3080 These commands allow GDB to retry failed TCP connections to a remote stub
3081 with a specified timeout period; this is useful if the stub is launched
3082 in parallel with GDB but may not be ready to accept connections immediately.
3084 set libthread-db-search-path
3085 show libthread-db-search-path
3086 Control list of directories which GDB will search for appropriate
3089 set schedule-multiple (on|off)
3090 show schedule-multiple
3091 Allow GDB to resume all threads of all processes or only threads of
3092 the current process.
3096 Use more aggressive caching for accesses to the stack. This improves
3097 performance of remote debugging (particularly backtraces) without
3098 affecting correctness.
3100 set interactive-mode (on|off|auto)
3101 show interactive-mode
3102 Control whether GDB runs in interactive mode (on) or not (off).
3103 When in interactive mode, GDB waits for the user to answer all
3104 queries. Otherwise, GDB does not wait and assumes the default
3105 answer. When set to auto (the default), GDB determines which
3106 mode to use based on the stdin settings.
3111 For program forks, this is replaced by the new more generic `info
3112 inferiors' command. To list checkpoints, you can still use the
3113 `info checkpoints' command, which was an alias for the `info forks'
3117 Replaced by the new `inferior' command. To switch between
3118 checkpoints, you can still use the `restart' command, which was an
3119 alias for the `fork' command.
3122 This is removed, since some targets don't have a notion of
3123 processes. To switch between processes, you can still use the
3124 `inferior' command using GDB's own inferior number.
3127 For program forks, this is replaced by the new more generic `kill
3128 inferior' command. To delete a checkpoint, you can still use the
3129 `delete checkpoint' command, which was an alias for the `delete
3133 For program forks, this is replaced by the new more generic `detach
3134 inferior' command. To detach a checkpoint, you can still use the
3135 `detach checkpoint' command, which was an alias for the `detach
3138 * New native configurations
3140 x86/x86_64 Darwin i[34567]86-*-darwin*
3142 x86_64 MinGW x86_64-*-mingw*
3146 Lattice Mico32 lm32-*
3147 x86 DICOS i[34567]86-*-dicos*
3148 x86_64 DICOS x86_64-*-dicos*
3151 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3152 (mingw32ce) debugging.
3158 These commands were actually not implemented on any target.
3160 *** Changes in GDB 6.8
3162 * New native configurations
3164 NetBSD/hppa hppa*-*netbsd*
3165 Xtensa GNU/Linux xtensa*-*-linux*
3169 NetBSD/hppa hppa*-*-netbsd*
3170 Xtensa GNU/Lunux xtensa*-*-linux*
3172 * Change in command line behavior -- corefiles vs. process ids.
3174 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3175 attaching to process NUMBER fails, GDB no longer attempts to open a
3176 core file named NUMBER. Attaching to a program using the -c option
3177 is no longer supported. Instead, use the '-p' or '--pid' options.
3179 * GDB can now be built as a native debugger for debugging Windows x86
3180 (mingw32) Portable Executable (PE) programs.
3182 * Pending breakpoints no longer change their number when their address
3185 * GDB now supports breakpoints with multiple locations,
3186 including breakpoints on C++ constructors, inside C++ templates,
3187 and in inlined functions.
3189 * GDB's ability to debug optimized code has been improved. GDB more
3190 accurately identifies function bodies and lexical blocks that occupy
3191 more than one contiguous range of addresses.
3193 * Target descriptions can now describe registers for PowerPC.
3195 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3196 registers on PowerPC targets.
3198 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3199 targets even when the libthread_db library is not available.
3201 * The GDB remote stub, gdbserver, now supports the new file transfer
3202 commands (remote put, remote get, and remote delete).
3204 * The GDB remote stub, gdbserver, now supports run and attach in
3205 extended-remote mode.
3207 * hppa*64*-*-hpux11* target broken
3208 The debugger is unable to start a program and fails with the following
3209 error: "Error trying to get information about dynamic linker".
3210 The gdb-6.7 release is also affected.
3212 * GDB now supports the --enable-targets= configure option to allow
3213 building a single GDB executable that supports multiple remote
3214 target architectures.
3216 * GDB now supports debugging C and C++ programs which use the
3217 Decimal Floating Point extension. In addition, the PowerPC target
3218 now has a set of pseudo-registers to inspect decimal float values
3219 stored in two consecutive float registers.
3221 * The -break-insert MI command can optionally create pending
3224 * Improved support for debugging Ada
3225 Many improvements to the Ada language support have been made. These
3227 - Better support for Ada2005 interface types
3228 - Improved handling of arrays and slices in general
3229 - Better support for Taft-amendment types
3230 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3232 - Improved command completion in Ada
3235 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3240 set print frame-arguments (all|scalars|none)
3241 show print frame-arguments
3242 The value of this variable can be changed to control which argument
3243 values should be printed by the debugger when displaying a frame.
3248 Transfer files to and from a remote target, and delete remote files.
3255 Transfer files to and from a remote target, and delete remote files.
3257 * New remote packets
3264 Open, close, read, write, and delete files on the remote system.
3267 Attach to an existing process on the remote system, in extended-remote
3271 Run a new process on the remote system, in extended-remote mode.
3273 *** Changes in GDB 6.7
3275 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3276 bfd, libiberty and opcodes, as revealed by static analysis donated by
3277 Coverity, Inc. (http://scan.coverity.com).
3279 * When looking up multiply-defined global symbols, GDB will now prefer the
3280 symbol definition in the current shared library if it was built using the
3281 -Bsymbolic linker option.
3283 * When the Text User Interface (TUI) is not configured, GDB will now
3284 recognize the -tui command-line option and print a message that the TUI
3287 * The GDB remote stub, gdbserver, now has lower overhead for high
3288 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3290 * GDB for MIPS targets now autodetects whether a remote target provides
3291 32-bit or 64-bit register values.
3293 * Support for C++ member pointers has been improved.
3295 * GDB now understands XML target descriptions, which specify the
3296 target's overall architecture. GDB can read a description from
3297 a local file or over the remote serial protocol.
3299 * Vectors of single-byte data use a new integer type which is not
3300 automatically displayed as character or string data.
3302 * The /s format now works with the print command. It displays
3303 arrays of single-byte integers and pointers to single-byte integers
3306 * Target descriptions can now describe target-specific registers,
3307 for architectures which have implemented the support (currently
3308 only ARM, M68K, and MIPS).
3310 * GDB and the GDB remote stub, gdbserver, now support the XScale
3313 * The GDB remote stub, gdbserver, has been updated to support
3314 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3315 has been rewritten to use the standard GDB remote protocol.
3317 * GDB can now step into C++ functions which are called through thunks.
3319 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3321 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3322 layout. It also supports a TextSeg= and DataSeg= response when only
3323 segment base addresses (rather than offsets) are available.
3325 * The /i format now outputs any trailing branch delay slot instructions
3326 immediately following the last instruction within the count specified.
3328 * The GDB remote protocol "T" stop reply packet now supports a
3329 "library" response. Combined with the new "qXfer:libraries:read"
3330 packet, this response allows GDB to debug shared libraries on targets
3331 where the operating system manages the list of loaded libraries (e.g.
3332 Windows and SymbianOS).
3334 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3335 (DLLs) on Windows and Windows CE targets.
3337 * GDB now supports a faster verification that a .debug file matches its binary
3338 according to its build-id signature, if the signature is present.
3344 Enable or disable hardware flow control (RTS/CTS) on the serial port
3345 when debugging using remote targets.
3347 set mem inaccessible-by-default
3348 show mem inaccessible-by-default
3349 If the target supplies a memory map, for instance via the remote
3350 protocol's "qXfer:memory-map:read" packet, setting this variable
3351 prevents GDB from accessing memory outside the memory map. This
3352 is useful for targets with memory mapped registers or which react
3353 badly to accesses of unmapped address space.
3355 set breakpoint auto-hw
3356 show breakpoint auto-hw
3357 If the target supplies a memory map, for instance via the remote
3358 protocol's "qXfer:memory-map:read" packet, setting this variable
3359 lets GDB use hardware breakpoints automatically for memory regions
3360 where it can not use software breakpoints. This covers both the
3361 "break" command and internal breakpoints used for other commands
3362 including "next" and "finish".
3365 catch exception unhandled
3366 Stop the program execution when Ada exceptions are raised.
3369 Stop the program execution when an Ada assertion failed.
3373 Set an alternate system root for target files. This is a more
3374 general version of "set solib-absolute-prefix", which is now
3375 an alias to "set sysroot".
3378 Provide extended SPU facility status information. This set of
3379 commands is available only when debugging the Cell/B.E. SPU
3382 * New native configurations
3384 OpenBSD/sh sh*-*openbsd*
3387 unset tdesc filename
3389 Use the specified local file as an XML target description, and do
3390 not query the target for its built-in description.
3394 OpenBSD/sh sh*-*-openbsd*
3395 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3396 Toshiba Media Processor mep-elf
3398 * New remote packets
3401 Ignore the specified signals; pass them directly to the debugged program
3402 without stopping other threads or reporting them to GDB.
3404 qXfer:features:read:
3405 Read an XML target description from the target, which describes its
3410 Read or write contents of an spufs file on the target system. These
3411 packets are available only on the Cell/B.E. SPU architecture.
3413 qXfer:libraries:read:
3414 Report the loaded shared libraries. Combined with new "T" packet
3415 response, this packet allows GDB to debug shared libraries on
3416 targets where the operating system manages the list of loaded
3417 libraries (e.g. Windows and SymbianOS).
3421 Support for these obsolete configurations has been removed.
3429 i[34567]86-*-lynxos*
3430 i[34567]86-*-netware*
3431 i[34567]86-*-sco3.2v5*
3432 i[34567]86-*-sco3.2v4*
3434 i[34567]86-*-sysv4.2*
3437 i[34567]86-*-unixware2*
3438 i[34567]86-*-unixware*
3447 * Other removed features
3454 Various m68k-only ROM monitors.
3461 Various Renesas ROM monitors and debugging interfaces for SH and
3466 Support for a Macraigor serial interface to on-chip debugging.
3467 GDB does not directly support the newer parallel or USB
3472 A debug information format. The predecessor to DWARF 2 and
3473 DWARF 3, which are still supported.
3475 Support for the HP aCC compiler on HP-UX/PA-RISC
3477 SOM-encapsulated symbolic debugging information, automatic
3478 invocation of pxdb, and the aCC custom C++ ABI. This does not
3479 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3480 with aCC can still be debugged on an assembly level.
3482 MIPS ".pdr" sections
3484 A MIPS-specific format used to describe stack frame layout
3485 in debugging information.
3489 GDB could work with an older version of Guile to debug
3490 the interpreter and Scheme programs running in it.
3492 set mips stack-arg-size
3493 set mips saved-gpreg-size
3495 Use "set mips abi" to control parameter passing for MIPS.
3497 *** Changes in GDB 6.6
3502 Cell Broadband Engine SPU spu-elf
3504 * GDB can now be configured as a cross-debugger targeting native Windows
3505 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3506 running on a Windows system over TCP/IP to debug Windows programs.
3508 * The GDB remote stub, gdbserver, has been updated to support Windows and
3509 Cygwin debugging. Both single-threaded and multi-threaded programs are
3512 * The "set trust-readonly-sections" command works again. This command was
3513 broken in GDB 6.3, 6.4, and 6.5.
3515 * The "load" command now supports writing to flash memory, if the remote
3516 stub provides the required support.
3518 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3519 longer requires symbolic debug information (e.g. DWARF-2).
3524 unset substitute-path
3525 show substitute-path
3526 Manage a list of substitution rules that GDB uses to rewrite the name
3527 of the directories where the sources are located. This can be useful
3528 for instance when the sources were moved to a different location
3529 between compilation and debugging.
3533 Print each CLI command as it is executed. Each command is prefixed with
3534 a number of `+' symbols representing the nesting depth.
3535 The source command now has a `-v' option to enable the same feature.
3539 The ARM Demon monitor support (RDP protocol, "target rdp").
3541 Kernel Object Display, an embedded debugging feature which only worked with
3542 an obsolete version of Cisco IOS.
3544 The 'set download-write-size' and 'show download-write-size' commands.
3546 * New remote packets
3549 Tell a stub about GDB client features, and request remote target features.
3550 The first feature implemented is PacketSize, which allows the target to
3551 specify the size of packets it can handle - to minimize the number of
3552 packets required and improve performance when connected to a remote
3556 Fetch an OS auxilliary vector from the remote stub. This packet is a
3557 more efficient replacement for qPart:auxv:read.
3559 qXfer:memory-map:read:
3560 Fetch a memory map from the remote stub, including information about
3561 RAM, ROM, and flash memory devices.
3566 Erase and program a flash memory device.
3568 * Removed remote packets
3571 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3572 used it, and only gdbserver implemented it.
3574 *** Changes in GDB 6.5
3578 Renesas M32C/M16C m32c-elf
3580 Morpho Technologies ms1 ms1-elf
3584 init-if-undefined Initialize a convenience variable, but
3585 only if it doesn't already have a value.
3587 The following commands are presently only implemented for native GNU/Linux:
3589 checkpoint Save a snapshot of the program state.
3591 restart <n> Return the program state to a
3592 previously saved state.
3594 info checkpoints List currently saved checkpoints.
3596 delete-checkpoint <n> Delete a previously saved checkpoint.
3598 set|show detach-on-fork Tell gdb whether to detach from a newly
3599 forked process, or to keep debugging it.
3601 info forks List forks of the user program that
3602 are available to be debugged.
3604 fork <n> Switch to debugging one of several
3605 forks of the user program that are
3606 available to be debugged.
3608 delete-fork <n> Delete a fork from the list of forks
3609 that are available to be debugged (and
3610 kill the forked process).
3612 detach-fork <n> Delete a fork from the list of forks
3613 that are available to be debugged (and
3614 allow the process to continue).
3618 Morpho Technologies ms2 ms1-elf
3620 * Improved Windows host support
3622 GDB now builds as a cross debugger hosted on i686-mingw32, including
3623 native console support, and remote communications using either
3624 network sockets or serial ports.
3626 * Improved Modula-2 language support
3628 GDB can now print most types in the Modula-2 syntax. This includes:
3629 basic types, set types, record types, enumerated types, range types,
3630 pointer types and ARRAY types. Procedure var parameters are correctly
3631 printed and hexadecimal addresses and character constants are also
3632 written in the Modula-2 syntax. Best results can be obtained by using
3633 GNU Modula-2 together with the -gdwarf-2 command line option.
3637 The ARM rdi-share module.
3639 The Netware NLM debug server.
3641 *** Changes in GDB 6.4
3643 * New native configurations
3645 OpenBSD/arm arm*-*-openbsd*
3646 OpenBSD/mips64 mips64-*-openbsd*
3650 Morpho Technologies ms1 ms1-elf
3652 * New command line options
3654 --batch-silent As for --batch, but totally silent.
3655 --return-child-result The debugger will exist with the same value
3656 the child (debugged) program exited with.
3657 --eval-command COMMAND, -ex COMMAND
3658 Execute a single GDB CLI command. This may be
3659 specified multiple times and in conjunction
3660 with the --command (-x) option.
3662 * Deprecated commands removed
3664 The following commands, that were deprecated in 2000, have been
3668 set|show arm disassembly-flavor set|show arm disassembler
3669 othernames set arm disassembler
3670 set|show remotedebug set|show debug remote
3671 set|show archdebug set|show debug arch
3672 set|show eventdebug set|show debug event
3675 * New BSD user-level threads support
3677 It is now possible to debug programs using the user-level threads
3678 library on OpenBSD and FreeBSD. Currently supported (target)
3681 FreeBSD/amd64 x86_64-*-freebsd*
3682 FreeBSD/i386 i386-*-freebsd*
3683 OpenBSD/i386 i386-*-openbsd*
3685 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3686 are not yet supported.
3688 * New support for Matsushita MN10300 w/sim added
3689 (Work in progress). mn10300-elf.
3691 * REMOVED configurations and files
3693 VxWorks and the XDR protocol *-*-vxworks
3694 Motorola MCORE mcore-*-*
3695 National Semiconductor NS32000 ns32k-*-*
3697 * New "set print array-indexes" command
3699 After turning this setting "on", GDB prints the index of each element
3700 when displaying arrays. The default is "off" to preserve the previous
3703 * VAX floating point support
3705 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3707 * User-defined command support
3709 In addition to using $arg0..$arg9 for argument passing, it is now possible
3710 to use $argc to determine now many arguments have been passed. See the
3711 section on user-defined commands in the user manual for more information.
3713 *** Changes in GDB 6.3:
3715 * New command line option
3717 GDB now accepts -l followed by a number to set the timeout for remote
3720 * GDB works with GCC -feliminate-dwarf2-dups
3722 GDB now supports a more compact representation of DWARF-2 debug
3723 information using DW_FORM_ref_addr references. These are produced
3724 by GCC with the option -feliminate-dwarf2-dups and also by some
3725 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3726 to use -feliminate-dwarf2-dups.
3728 * Internationalization
3730 When supported by the host system, GDB will be built with
3731 internationalization (libintl). The task of marking up the sources is
3732 continued, we're looking forward to our first translation.
3736 Initial support for debugging programs compiled with the GNAT
3737 implementation of the Ada programming language has been integrated
3738 into GDB. In this release, support is limited to expression evaluation.
3740 * New native configurations
3742 GNU/Linux/m32r m32r-*-linux-gnu
3746 GDB's remote protocol now includes support for the 'p' packet. This
3747 packet is used to fetch individual registers from a remote inferior.
3749 * END-OF-LIFE registers[] compatibility module
3751 GDB's internal register infrastructure has been completely rewritten.
3752 The new infrastructure making possible the implementation of key new
3753 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3756 GDB 6.3 will be the last release to include the the registers[]
3757 compatibility module that allowed out-of-date configurations to
3758 continue to work. This change directly impacts the following
3768 powerpc bdm protocol
3770 Unless there is activity to revive these configurations, they will be
3771 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3773 * OBSOLETE configurations and files
3775 Configurations that have been declared obsolete in this release have
3776 been commented out. Unless there is activity to revive these
3777 configurations, the next release of GDB will have their sources
3778 permanently REMOVED.
3787 *** Changes in GDB 6.2.1:
3789 * MIPS `break main; run' gave an heuristic-fence-post warning
3791 When attempting to run even a simple program, a warning about
3792 heuristic-fence-post being hit would be reported. This problem has
3795 * MIPS IRIX 'long double' crashed GDB
3797 When examining a long double variable, GDB would get a segmentation
3798 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3799 IRIX long double values).
3803 A bug in the VAX stack code was causing problems with the "next"
3804 command. This problem has been fixed.
3806 *** Changes in GDB 6.2:
3808 * Fix for ``many threads''
3810 On GNU/Linux systems that use the NPTL threads library, a program
3811 rapidly creating and deleting threads would confuse GDB leading to the
3814 ptrace: No such process.
3815 thread_db_get_info: cannot get thread info: generic error
3817 This problem has been fixed.
3819 * "-async" and "-noasync" options removed.
3821 Support for the broken "-noasync" option has been removed (it caused
3824 * New ``start'' command.
3826 This command runs the program until the begining of the main procedure.
3828 * New BSD Kernel Data Access Library (libkvm) interface
3830 Using ``target kvm'' it is now possible to debug kernel core dumps and
3831 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3832 platforms. Currently supported (native-only) configurations are:
3834 FreeBSD/amd64 x86_64-*-freebsd*
3835 FreeBSD/i386 i?86-*-freebsd*
3836 NetBSD/i386 i?86-*-netbsd*
3837 NetBSD/m68k m68*-*-netbsd*
3838 NetBSD/sparc sparc-*-netbsd*
3839 OpenBSD/amd64 x86_64-*-openbsd*
3840 OpenBSD/i386 i?86-*-openbsd*
3841 OpenBSD/m68k m68*-openbsd*
3842 OpenBSD/sparc sparc-*-openbsd*
3844 * Signal trampoline code overhauled
3846 Many generic problems with GDB's signal handling code have been fixed.
3847 These include: backtraces through non-contiguous stacks; recognition
3848 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3849 call; backtrace through a signal trampoline; step into and out of
3850 signal handlers; and single-stepping in the signal trampoline.
3852 Please note that kernel bugs are a limiting factor here. These
3853 features have been shown to work on an s390 GNU/Linux system that
3854 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3856 * Cygwin support for DWARF 2 added.
3858 * New native configurations
3860 GNU/Linux/hppa hppa*-*-linux*
3861 OpenBSD/hppa hppa*-*-openbsd*
3862 OpenBSD/m68k m68*-*-openbsd*
3863 OpenBSD/m88k m88*-*-openbsd*
3864 OpenBSD/powerpc powerpc-*-openbsd*
3865 NetBSD/vax vax-*-netbsd*
3866 OpenBSD/vax vax-*-openbsd*
3868 * END-OF-LIFE frame compatibility module
3870 GDB's internal frame infrastructure has been completely rewritten.
3871 The new infrastructure making it possible to support key new features
3872 including DWARF 2 Call Frame Information. To aid in the task of
3873 migrating old configurations to this new infrastructure, a
3874 compatibility module, that allowed old configurations to continue to
3875 work, was also included.
3877 GDB 6.2 will be the last release to include this frame compatibility
3878 module. This change directly impacts the following configurations:
3888 Unless there is activity to revive these configurations, they will be
3889 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3891 * REMOVED configurations and files
3893 Sun 3, running SunOS 3 m68*-*-sunos3*
3894 Sun 3, running SunOS 4 m68*-*-sunos4*
3895 Sun 2, running SunOS 3 m68000-*-sunos3*
3896 Sun 2, running SunOS 4 m68000-*-sunos4*
3897 Motorola 680x0 running LynxOS m68*-*-lynxos*
3898 AT&T 3b1/Unix pc m68*-att-*
3899 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3900 decstation mips-dec-* mips-little-*
3901 riscos mips-*-riscos* mips-*-sysv*
3902 sonymips mips-sony-*
3903 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3905 *** Changes in GDB 6.1.1:
3907 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3909 The TUI (Text-mode User Interface) is now built as part of a default
3910 GDB configuration. It is enabled by either selecting the TUI with the
3911 command line option "-i=tui" or by running the separate "gdbtui"
3912 program. For more information on the TUI, see the manual "Debugging
3915 * Pending breakpoint support (also included in GDB 6.1)
3917 Support has been added to allow you to specify breakpoints in shared
3918 libraries that have not yet been loaded. If a breakpoint location
3919 cannot be found, and the "breakpoint pending" option is set to auto,
3920 GDB queries you if you wish to make the breakpoint pending on a future
3921 shared-library load. If and when GDB resolves the breakpoint symbol,
3922 the pending breakpoint is removed as one or more regular breakpoints
3925 Pending breakpoints are very useful for GCJ Java debugging.
3927 * Fixed ISO-C build problems
3929 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3930 non ISO-C code that stopped them being built using a more strict ISO-C
3931 compiler (e.g., IBM's C compiler).
3933 * Fixed build problem on IRIX 5
3935 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3936 wasn't able to compile compile on an IRIX 5 system.
3938 * Added execute permission to gdb/gdbserver/configure
3940 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3941 permission. This bug would cause configure to fail on a number of
3942 systems (Solaris, IRIX). Ref: server/519.
3944 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3946 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3947 has been updated to use constant array sizes.
3949 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3951 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3952 its generated DWARF Call Frame Info. This encoding was causing GDB to
3953 panic, that panic has been fixed. Ref: gdb/1628.
3955 * Fixed a problem when examining parameters in shared library code.
3957 When examining parameters in optimized shared library code generated
3958 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3959 not available''. GDB now correctly displays the variable's value.
3961 *** Changes in GDB 6.1:
3963 * Removed --with-mmalloc
3965 Support for the mmalloc memory manager has been removed, as it
3966 conflicted with the internal gdb byte cache.
3968 * Changes in AMD64 configurations
3970 The AMD64 target now includes the %cs and %ss registers. As a result
3971 the AMD64 remote protocol has changed; this affects the floating-point
3972 and SSE registers. If you rely on those registers for your debugging,
3973 you should upgrade gdbserver on the remote side.
3975 * Revised SPARC target
3977 The SPARC target has been completely revised, incorporating the
3978 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3979 support for LynxOS and SunOS 4 has been dropped. Calling functions
3980 from within GDB on operating systems with a non-executable stack
3981 (Solaris, OpenBSD) now works.
3985 GDB has a new C++ demangler which does a better job on the mangled
3986 names generated by current versions of g++. It also runs faster, so
3987 with this and other changes gdb should now start faster on large C++
3990 * DWARF 2 Location Expressions
3992 GDB support for location expressions has been extended to support function
3993 arguments and frame bases. Older versions of GDB could crash when they
3996 * C++ nested types and namespaces
3998 GDB's support for nested types and namespaces in C++ has been
3999 improved, especially if you use the DWARF 2 debugging format. (This
4000 is the default for recent versions of GCC on most platforms.)
4001 Specifically, if you have a class "Inner" defined within a class or
4002 namespace "Outer", then GDB realizes that the class's name is
4003 "Outer::Inner", not simply "Inner". This should greatly reduce the
4004 frequency of complaints about not finding RTTI symbols. In addition,
4005 if you are stopped at inside of a function defined within a namespace,
4006 GDB modifies its name lookup accordingly.
4008 * New native configurations
4010 NetBSD/amd64 x86_64-*-netbsd*
4011 OpenBSD/amd64 x86_64-*-openbsd*
4012 OpenBSD/alpha alpha*-*-openbsd*
4013 OpenBSD/sparc sparc-*-openbsd*
4014 OpenBSD/sparc64 sparc64-*-openbsd*
4016 * New debugging protocols
4018 M32R with SDI protocol m32r-*-elf*
4020 * "set prompt-escape-char" command deleted.
4022 The command "set prompt-escape-char" has been deleted. This command,
4023 and its very obscure effet on GDB's prompt, was never documented,
4024 tested, nor mentioned in the NEWS file.
4026 * OBSOLETE configurations and files
4028 Configurations that have been declared obsolete in this release have
4029 been commented out. Unless there is activity to revive these
4030 configurations, the next release of GDB will have their sources
4031 permanently REMOVED.
4033 Sun 3, running SunOS 3 m68*-*-sunos3*
4034 Sun 3, running SunOS 4 m68*-*-sunos4*
4035 Sun 2, running SunOS 3 m68000-*-sunos3*
4036 Sun 2, running SunOS 4 m68000-*-sunos4*
4037 Motorola 680x0 running LynxOS m68*-*-lynxos*
4038 AT&T 3b1/Unix pc m68*-att-*
4039 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4040 decstation mips-dec-* mips-little-*
4041 riscos mips-*-riscos* mips-*-sysv*
4042 sonymips mips-sony-*
4043 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4045 * REMOVED configurations and files
4047 SGI Irix-4.x mips-sgi-irix4 or iris4
4048 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4049 Z8000 simulator z8k-zilog-none or z8ksim
4050 Matsushita MN10200 w/simulator mn10200-*-*
4051 H8/500 simulator h8500-hitachi-hms or h8500hms
4052 HP/PA running BSD hppa*-*-bsd*
4053 HP/PA running OSF/1 hppa*-*-osf*
4054 HP/PA Pro target hppa*-*-pro*
4055 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4056 386BSD i[3456]86-*-bsd*
4057 Sequent family i[3456]86-sequent-sysv4*
4058 i[3456]86-sequent-sysv*
4059 i[3456]86-sequent-bsd*
4060 SPARC running LynxOS sparc-*-lynxos*
4061 SPARC running SunOS 4 sparc-*-sunos4*
4062 Tsqware Sparclet sparclet-*-*
4063 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4065 *** Changes in GDB 6.0:
4069 Support for debugging the Objective-C programming language has been
4070 integrated into GDB.
4072 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4074 DWARF 2's Call Frame Information makes available compiler generated
4075 information that more exactly describes the program's run-time stack.
4076 By using this information, GDB is able to provide more robust stack
4079 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4080 have been updated to use a new backtrace mechanism which includes
4081 DWARF 2 CFI support.
4085 GDB's remote protocol has been extended to include support for hosted
4086 file I/O (where the remote target uses GDB's file system). See GDB's
4087 remote protocol documentation for details.
4089 * All targets using the new architecture framework.
4091 All of GDB's targets have been updated to use the new internal
4092 architecture framework. The way is now open for future GDB releases
4093 to include cross-architecture native debugging support (i386 on amd64,
4096 * GNU/Linux's Thread Local Storage (TLS)
4098 GDB now includes support for for the GNU/Linux implementation of
4099 per-thread variables.
4101 * GNU/Linux's Native POSIX Thread Library (NPTL)
4103 GDB's thread code has been updated to work with either the new
4104 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4106 * Separate debug info.
4108 GDB, in conjunction with BINUTILS, now supports a mechanism for
4109 automatically loading debug information from a separate file. Instead
4110 of shipping full debug and non-debug versions of system libraries,
4111 system integrators can now instead ship just the stripped libraries
4112 and optional debug files.
4114 * DWARF 2 Location Expressions
4116 DWARF 2 Location Expressions allow the compiler to more completely
4117 describe the location of variables (even in optimized code) to the
4120 GDB now includes preliminary support for location expressions (support
4121 for DW_OP_piece is still missing).
4125 A number of long standing bugs that caused GDB to die while starting a
4126 Java application have been fixed. GDB's Java support is now
4127 considered "useable".
4129 * GNU/Linux support for fork, vfork, and exec.
4131 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4132 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4135 * GDB supports logging output to a file
4137 There are two new commands, "set logging" and "show logging", which can be
4138 used to capture GDB's output to a file.
4140 * The meaning of "detach" has changed for gdbserver
4142 The "detach" command will now resume the application, as documented. To
4143 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4146 * d10v, m68hc11 `regs' command deprecated
4148 The `info registers' command has been updated so that it displays the
4149 registers using a format identical to the old `regs' command.
4153 A new command, "maint set profile on/off", has been added. This command can
4154 be used to enable or disable profiling while running GDB, to profile a
4155 session or a set of commands. In addition there is a new configure switch,
4156 "--enable-profiling", which will cause GDB to be compiled with profiling
4157 data, for more informative profiling results.
4159 * Default MI syntax changed to "mi2".
4161 The default MI (machine interface) syntax, enabled by the command line
4162 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4163 "mi1", can be enabled by specifying the option "-i=mi1".
4165 Support for the original "mi0" syntax (included in GDB 5.0) has been
4168 Fix for gdb/192: removed extraneous space when displaying frame level.
4169 Fix for gdb/672: update changelist is now output in mi list format.
4170 Fix for gdb/702: a -var-assign that updates the value now shows up
4171 in a subsequent -var-update.
4173 * New native configurations.
4175 FreeBSD/amd64 x86_64-*-freebsd*
4177 * Multi-arched targets.
4179 HP/PA HPUX11 hppa*-*-hpux*
4180 Renesas M32R/D w/simulator m32r-*-elf*
4182 * OBSOLETE configurations and files
4184 Configurations that have been declared obsolete in this release have
4185 been commented out. Unless there is activity to revive these
4186 configurations, the next release of GDB will have their sources
4187 permanently REMOVED.
4189 Z8000 simulator z8k-zilog-none or z8ksim
4190 Matsushita MN10200 w/simulator mn10200-*-*
4191 H8/500 simulator h8500-hitachi-hms or h8500hms
4192 HP/PA running BSD hppa*-*-bsd*
4193 HP/PA running OSF/1 hppa*-*-osf*
4194 HP/PA Pro target hppa*-*-pro*
4195 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4196 Sequent family i[3456]86-sequent-sysv4*
4197 i[3456]86-sequent-sysv*
4198 i[3456]86-sequent-bsd*
4199 Tsqware Sparclet sparclet-*-*
4200 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4202 * REMOVED configurations and files
4205 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4206 IBM AIX PS/2 i[3456]86-*-aix
4207 i386 running Mach 3.0 i[3456]86-*-mach3*
4208 i386 running Mach i[3456]86-*-mach*
4209 i386 running OSF/1 i[3456]86-*osf1mk*
4210 HP/Apollo 68k Family m68*-apollo*-sysv*,
4212 m68*-hp-bsd*, m68*-hp-hpux*
4213 Argonaut Risc Chip (ARC) arc-*-*
4214 Mitsubishi D30V d30v-*-*
4215 Fujitsu FR30 fr30-*-elf*
4216 OS/9000 i[34]86-*-os9k
4217 I960 with MON960 i960-*-coff
4219 * MIPS $fp behavior changed
4221 The convenience variable $fp, for the MIPS, now consistently returns
4222 the address of the current frame's base. Previously, depending on the
4223 context, $fp could refer to either $sp or the current frame's base
4224 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4225 The GNU Source-Level Debugger''.
4227 *** Changes in GDB 5.3:
4229 * GNU/Linux shared library multi-threaded performance improved.
4231 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4232 `/proc', in preference to `ptrace' for memory reads. This may result
4233 in an improvement in the start-up time of multi-threaded, shared
4234 library applications when run under GDB. One GDB user writes: ``loads
4235 shared libs like mad''.
4237 * ``gdbserver'' now supports multi-threaded applications on some targets
4239 Support for debugging multi-threaded applications which use
4240 the GNU/Linux LinuxThreads package has been added for
4241 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4242 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4244 * GDB now supports C/C++ preprocessor macros.
4246 GDB now expands preprocessor macro invocations in C/C++ expressions,
4247 and provides various commands for showing macro definitions and how
4250 The new command `macro expand EXPRESSION' expands any macro
4251 invocations in expression, and shows the result.
4253 The new command `show macro MACRO-NAME' shows the definition of the
4254 macro named MACRO-NAME, and where it was defined.
4256 Most compilers don't include information about macros in the debugging
4257 information by default. In GCC 3.1, for example, you need to compile
4258 your program with the options `-gdwarf-2 -g3'. If the macro
4259 information is present in the executable, GDB will read it.
4261 * Multi-arched targets.
4263 DEC Alpha (partial) alpha*-*-*
4264 DEC VAX (partial) vax-*-*
4266 National Semiconductor NS32000 (partial) ns32k-*-*
4267 Motorola 68000 (partial) m68k-*-*
4268 Motorola MCORE mcore-*-*
4272 Fujitsu FRV architecture added by Red Hat frv*-*-*
4275 * New native configurations
4277 Alpha NetBSD alpha*-*-netbsd*
4278 SH NetBSD sh*-*-netbsdelf*
4279 MIPS NetBSD mips*-*-netbsd*
4280 UltraSPARC NetBSD sparc64-*-netbsd*
4282 * OBSOLETE configurations and files
4284 Configurations that have been declared obsolete in this release have
4285 been commented out. Unless there is activity to revive these
4286 configurations, the next release of GDB will have their sources
4287 permanently REMOVED.
4289 Mitsubishi D30V d30v-*-*
4290 OS/9000 i[34]86-*-os9k
4291 IBM AIX PS/2 i[3456]86-*-aix
4292 Fujitsu FR30 fr30-*-elf*
4293 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4294 Argonaut Risc Chip (ARC) arc-*-*
4295 i386 running Mach 3.0 i[3456]86-*-mach3*
4296 i386 running Mach i[3456]86-*-mach*
4297 i386 running OSF/1 i[3456]86-*osf1mk*
4298 HP/Apollo 68k Family m68*-apollo*-sysv*,
4300 m68*-hp-bsd*, m68*-hp-hpux*
4301 I960 with MON960 i960-*-coff
4303 * OBSOLETE languages
4305 CHILL, a Pascal like language used by telecommunications companies.
4307 * REMOVED configurations and files
4309 AMD 29k family via UDI a29k-amd-udi, udi29k
4310 A29K VxWorks a29k-*-vxworks
4311 AMD 29000 embedded, using EBMON a29k-none-none
4312 AMD 29000 embedded with COFF a29k-none-coff
4313 AMD 29000 embedded with a.out a29k-none-aout
4315 testsuite/gdb.hp/gdb.threads-hp/ directory
4317 * New command "set max-user-call-depth <nnn>"
4319 This command allows the user to limit the call depth of user-defined
4320 commands. The default is 1024.
4322 * Changes in FreeBSD/i386 native debugging.
4324 Support for the "generate-core-file" has been added.
4326 * New commands "dump", "append", and "restore".
4328 These commands allow data to be copied from target memory
4329 to a bfd-format or binary file (dump and append), and back
4330 from a file into memory (restore).
4332 * Improved "next/step" support on multi-processor Alpha Tru64.
4334 The previous single-step mechanism could cause unpredictable problems,
4335 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4336 of a software single-step mechanism prevents this.
4338 *** Changes in GDB 5.2.1:
4346 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4347 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4348 Fix, by Joel Brobecker imported from mainline.
4350 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4351 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4352 Fix, by Fred Fish, imported from mainline.
4354 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4355 Surprisingly enough, it works now.
4356 By Michal Ludvig, imported from mainline.
4358 i386 hardware watchpoint support:
4359 avoid misses on second run for some targets.
4360 By Pierre Muller, imported from mainline.
4362 *** Changes in GDB 5.2:
4364 * New command "set trust-readonly-sections on[off]".
4366 This command is a hint that tells gdb that read-only sections
4367 really are read-only (ie. that their contents will not change).
4368 In this mode, gdb will go to the object file rather than the
4369 target to read memory from read-only sections (such as ".text").
4370 This can be a significant performance improvement on some
4371 (notably embedded) targets.
4373 * New command "generate-core-file" (or "gcore").
4375 This new gdb command allows the user to drop a core file of the child
4376 process state at any time. So far it's been implemented only for
4377 GNU/Linux and Solaris, but should be relatively easily ported to other
4378 hosts. Argument is core file name (defaults to core.<pid>).
4380 * New command line option
4382 GDB now accepts --pid or -p followed by a process id.
4384 * Change in command line behavior -- corefiles vs. process ids.
4386 There is a subtle behavior in the way in which GDB handles
4387 command line arguments. The first non-flag argument is always
4388 a program to debug, but the second non-flag argument may either
4389 be a corefile or a process id. Previously, GDB would attempt to
4390 open the second argument as a corefile, and if that failed, would
4391 issue a superfluous error message and then attempt to attach it as
4392 a process. Now, if the second argument begins with a non-digit,
4393 it will be treated as a corefile. If it begins with a digit,
4394 GDB will attempt to attach it as a process, and if no such process
4395 is found, will then attempt to open it as a corefile.
4397 * Changes in ARM configurations.
4399 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4400 configuration is fully multi-arch.
4402 * New native configurations
4404 ARM NetBSD arm*-*-netbsd*
4405 x86 OpenBSD i[3456]86-*-openbsd*
4406 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4407 Sparc64 running FreeBSD sparc64-*-freebsd*
4411 Sanyo XStormy16 xstormy16-elf
4413 * OBSOLETE configurations and files
4415 Configurations that have been declared obsolete in this release have
4416 been commented out. Unless there is activity to revive these
4417 configurations, the next release of GDB will have their sources
4418 permanently REMOVED.
4420 AMD 29k family via UDI a29k-amd-udi, udi29k
4421 A29K VxWorks a29k-*-vxworks
4422 AMD 29000 embedded, using EBMON a29k-none-none
4423 AMD 29000 embedded with COFF a29k-none-coff
4424 AMD 29000 embedded with a.out a29k-none-aout
4426 testsuite/gdb.hp/gdb.threads-hp/ directory
4428 * REMOVED configurations and files
4430 TI TMS320C80 tic80-*-*
4432 PowerPC Solaris powerpcle-*-solaris*
4433 PowerPC Windows NT powerpcle-*-cygwin32
4434 PowerPC Netware powerpc-*-netware*
4435 Harris/CXUX m88k m88*-harris-cxux*
4436 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4437 ns32k-utek-sysv* ns32k-utek-*
4438 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4439 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4440 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4441 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4442 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4444 * Changes to command line processing
4446 The new `--args' feature can be used to specify command-line arguments
4447 for the inferior from gdb's command line.
4449 * Changes to key bindings
4451 There is a new `operate-and-get-next' function bound to `C-o'.
4453 *** Changes in GDB 5.1.1
4455 Fix compile problem on DJGPP.
4457 Fix a problem with floating-point registers on the i386 being
4460 Fix to stop GDB crashing on .debug_str debug info.
4462 Numerous documentation fixes.
4464 Numerous testsuite fixes.
4466 *** Changes in GDB 5.1:
4468 * New native configurations
4470 Alpha FreeBSD alpha*-*-freebsd*
4471 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4472 MIPS GNU/Linux mips*-*-linux*
4473 MIPS SGI Irix 6.x mips*-sgi-irix6*
4474 ia64 AIX ia64-*-aix*
4475 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4479 Motorola 68HC11 and 68HC12 m68hc11-elf
4481 UltraSparc running GNU/Linux sparc64-*-linux*
4483 * OBSOLETE configurations and files
4485 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4486 Harris/CXUX m88k m88*-harris-cxux*
4487 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4488 ns32k-utek-sysv* ns32k-utek-*
4489 TI TMS320C80 tic80-*-*
4491 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4492 PowerPC Solaris powerpcle-*-solaris*
4493 PowerPC Windows NT powerpcle-*-cygwin32
4494 PowerPC Netware powerpc-*-netware*
4495 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4496 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4497 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4498 Apple Macintosh (MPW) host N/A
4500 stuff.c (Program to stuff files into a specially prepared space in kdb)
4501 kdb-start.c (Main loop for the standalone kernel debugger)
4503 Configurations that have been declared obsolete in this release have
4504 been commented out. Unless there is activity to revive these
4505 configurations, the next release of GDB will have their sources
4506 permanently REMOVED.
4508 * REMOVED configurations and files
4510 Altos 3068 m68*-altos-*
4511 Convex c1-*-*, c2-*-*
4513 ARM RISCix arm-*-* (as host)
4517 * GDB has been converted to ISO C.
4519 GDB's source code has been converted to ISO C. In particular, the
4520 sources are fully protoized, and rely on standard headers being
4525 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4527 * The MI enabled by default.
4529 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4530 revised and enabled by default. Packages which use GDB as a debugging
4531 engine behind a UI or another front end are encouraged to switch to
4532 using the GDB/MI interface, instead of the old annotations interface
4533 which is now deprecated.
4535 * Support for debugging Pascal programs.
4537 GDB now includes support for debugging Pascal programs. The following
4538 main features are supported:
4540 - Pascal-specific data types such as sets;
4542 - automatic recognition of Pascal sources based on file-name
4545 - Pascal-style display of data types, variables, and functions;
4547 - a Pascal expression parser.
4549 However, some important features are not yet supported.
4551 - Pascal string operations are not supported at all;
4553 - there are some problems with boolean types;
4555 - Pascal type hexadecimal constants are not supported
4556 because they conflict with the internal variables format;
4558 - support for Pascal objects and classes is not full yet;
4560 - unlike Pascal, GDB is case-sensitive for symbol names.
4562 * Changes in completion.
4564 Commands such as `shell', `run' and `set args', which pass arguments
4565 to inferior programs, now complete on file names, similar to what
4566 users expect at the shell prompt.
4568 Commands which accept locations, such as `disassemble', `print',
4569 `breakpoint', `until', etc. now complete on filenames as well as
4570 program symbols. Thus, if you type "break foob TAB", and the source
4571 files linked into the programs include `foobar.c', that file name will
4572 be one of the candidates for completion. However, file names are not
4573 considered for completion after you typed a colon that delimits a file
4574 name from a name of a function in that file, as in "break foo.c:bar".
4576 `set demangle-style' completes on available demangling styles.
4578 * New platform-independent commands:
4580 It is now possible to define a post-hook for a command as well as a
4581 hook that runs before the command. For more details, see the
4582 documentation of `hookpost' in the GDB manual.
4584 * Changes in GNU/Linux native debugging.
4586 Support for debugging multi-threaded programs has been completely
4587 revised for all platforms except m68k and sparc. You can now debug as
4588 many threads as your system allows you to have.
4590 Attach/detach is supported for multi-threaded programs.
4592 Support for SSE registers was added for x86. This doesn't work for
4593 multi-threaded programs though.
4595 * Changes in MIPS configurations.
4597 Multi-arch support is enabled for all MIPS configurations.
4599 GDB can now be built as native debugger on SGI Irix 6.x systems for
4600 debugging n32 executables. (Debugging 64-bit executables is not yet
4603 * Unified support for hardware watchpoints in all x86 configurations.
4605 Most (if not all) native x86 configurations support hardware-assisted
4606 breakpoints and watchpoints in a unified manner. This support
4607 implements debug register sharing between watchpoints, which allows to
4608 put a virtually infinite number of watchpoints on the same address,
4609 and also supports watching regions up to 16 bytes with several debug
4612 The new maintenance command `maintenance show-debug-regs' toggles
4613 debugging print-outs in functions that insert, remove, and test
4614 watchpoints and hardware breakpoints.
4616 * Changes in the DJGPP native configuration.
4618 New command ``info dos sysinfo'' displays assorted information about
4619 the CPU, OS, memory, and DPMI server.
4621 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4622 display information about segment descriptors stored in GDT, LDT, and
4625 New commands ``info dos pde'' and ``info dos pte'' display entries
4626 from Page Directory and Page Tables (for now works with CWSDPMI only).
4627 New command ``info dos address-pte'' displays the Page Table entry for
4628 a given linear address.
4630 GDB can now pass command lines longer than 126 characters to the
4631 program being debugged (requires an update to the libdbg.a library
4632 which is part of the DJGPP development kit).
4634 DWARF2 debug info is now supported.
4636 It is now possible to `step' and `next' through calls to `longjmp'.
4638 * Changes in documentation.
4640 All GDB documentation was converted to GFDL, the GNU Free
4641 Documentation License.
4643 Tracepoints-related commands are now fully documented in the GDB
4646 TUI, the Text-mode User Interface, is now documented in the manual.
4648 Tracepoints-related commands are now fully documented in the GDB
4651 The "GDB Internals" manual now has an index. It also includes
4652 documentation of `ui_out' functions, GDB coding standards, x86
4653 hardware watchpoints, and memory region attributes.
4655 * GDB's version number moved to ``version.in''
4657 The Makefile variable VERSION has been replaced by the file
4658 ``version.in''. People creating GDB distributions should update the
4659 contents of this file.
4663 GUD support is now a standard part of the EMACS distribution.
4665 *** Changes in GDB 5.0:
4667 * Improved support for debugging FP programs on x86 targets
4669 Unified and much-improved support for debugging floating-point
4670 programs on all x86 targets. In particular, ``info float'' now
4671 displays the FP registers in the same format on all x86 targets, with
4672 greater level of detail.
4674 * Improvements and bugfixes in hardware-assisted watchpoints
4676 It is now possible to watch array elements, struct members, and
4677 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4678 on x86 targets no longer erroneously trigger when the address is
4681 * Improvements in the native DJGPP version of GDB
4683 The distribution now includes all the scripts and auxiliary files
4684 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4685 machines ``out of the box''.
4687 The DJGPP version can now debug programs that use signals. It is
4688 possible to catch signals that happened in the debuggee, deliver
4689 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4690 would kill the program being debugged.) Programs that hook hardware
4691 interrupts (keyboard, timer, etc.) can also be debugged.
4693 It is now possible to debug DJGPP programs that redirect their
4694 standard handles or switch them to raw (as opposed to cooked) mode, or
4695 even close them. The command ``run < foo > bar'' works as expected,
4696 and ``info terminal'' reports useful information about the debuggee's
4697 terminal, including raw/cooked mode, redirection, etc.
4699 The DJGPP version now uses termios functions for console I/O, which
4700 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4703 DOS-style file names with drive letters are now fully supported by
4706 It is now possible to debug DJGPP programs that switch their working
4707 directory. It is also possible to rerun the debuggee any number of
4708 times without restarting GDB; thus, you can use the same setup,
4709 breakpoints, etc. for many debugging sessions.
4711 * New native configurations
4713 ARM GNU/Linux arm*-*-linux*
4714 PowerPC GNU/Linux powerpc-*-linux*
4718 Motorola MCore mcore-*-*
4719 x86 VxWorks i[3456]86-*-vxworks*
4720 PowerPC VxWorks powerpc-*-vxworks*
4721 TI TMS320C80 tic80-*-*
4723 * OBSOLETE configurations
4725 Altos 3068 m68*-altos-*
4726 Convex c1-*-*, c2-*-*
4728 ARM RISCix arm-*-* (as host)
4731 Configurations that have been declared obsolete will be commented out,
4732 but the code will be left in place. If there is no activity to revive
4733 these configurations before the next release of GDB, the sources will
4734 be permanently REMOVED.
4736 * Gould support removed
4738 Support for the Gould PowerNode and NP1 has been removed.
4740 * New features for SVR4
4742 On SVR4 native platforms (such as Solaris), if you attach to a process
4743 without first loading a symbol file, GDB will now attempt to locate and
4744 load symbols from the running process's executable file.
4746 * Many C++ enhancements
4748 C++ support has been greatly improved. Overload resolution now works properly
4749 in almost all cases. RTTI support is on the way.
4751 * Remote targets can connect to a sub-program
4753 A popen(3) style serial-device has been added. This device starts a
4754 sub-process (such as a stand-alone simulator) and then communicates
4755 with that. The sub-program to run is specified using the syntax
4756 ``|<program> <args>'' vis:
4758 (gdb) set remotedebug 1
4759 (gdb) target extended-remote |mn10300-elf-sim program-args
4761 * MIPS 64 remote protocol
4763 A long standing bug in the mips64 remote protocol where by GDB
4764 expected certain 32 bit registers (ex SR) to be transfered as 32
4765 instead of 64 bits has been fixed.
4767 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4768 added to provide backward compatibility with older versions of GDB.
4770 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4772 The command ``set remotebinarydownload'' command has been replaced by
4773 ``set remote X-packet''. Other commands in ``set remote'' family
4774 include ``set remote P-packet''.
4776 * Breakpoint commands accept ranges.
4778 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4779 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4780 ``tracepoint passcount'' also accepts a range of tracepoints.
4782 * ``apropos'' command added.
4784 The ``apropos'' command searches through command names and
4785 documentation strings, printing out matches, making it much easier to
4786 try to find a command that does what you are looking for.
4790 A new machine oriented interface (MI) has been added to GDB. This
4791 interface is designed for debug environments running GDB as a separate
4792 process. This is part of the long term libGDB project. See the
4793 "GDB/MI" chapter of the GDB manual for further information. It can be
4794 enabled by configuring with:
4796 .../configure --enable-gdbmi
4798 *** Changes in GDB-4.18:
4800 * New native configurations
4802 HP-UX 10.20 hppa*-*-hpux10.20
4803 HP-UX 11.x hppa*-*-hpux11.0*
4804 M68K GNU/Linux m68*-*-linux*
4808 Fujitsu FR30 fr30-*-elf*
4809 Intel StrongARM strongarm-*-*
4810 Mitsubishi D30V d30v-*-*
4812 * OBSOLETE configurations
4814 Gould PowerNode, NP1 np1-*-*, pn-*-*
4816 Configurations that have been declared obsolete will be commented out,
4817 but the code will be left in place. If there is no activity to revive
4818 these configurations before the next release of GDB, the sources will
4819 be permanently REMOVED.
4823 As a compatibility experiment, GDB's source files buildsym.h and
4824 buildsym.c have been converted to pure standard C, no longer
4825 containing any K&R compatibility code. We believe that all systems in
4826 use today either come with a standard C compiler, or have a GCC port
4827 available. If this is not true, please report the affected
4828 configuration to bug-gdb@gnu.org immediately. See the README file for
4829 information about getting a standard C compiler if you don't have one
4834 GDB now uses readline 2.2.
4836 * set extension-language
4838 You can now control the mapping between filename extensions and source
4839 languages by using the `set extension-language' command. For instance,
4840 you can ask GDB to treat .c files as C++ by saying
4841 set extension-language .c c++
4842 The command `info extensions' lists all of the recognized extensions
4843 and their associated languages.
4845 * Setting processor type for PowerPC and RS/6000
4847 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4848 you can use the `set processor' command to specify what variant of the
4849 PowerPC family you are debugging. The command
4853 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4854 following PowerPC and RS6000 variants:
4856 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4857 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4859 403GC IBM PowerPC 403GC
4860 505 Motorola PowerPC 505
4861 860 Motorola PowerPC 860 or 850
4862 601 Motorola PowerPC 601
4863 602 Motorola PowerPC 602
4864 603 Motorola/IBM PowerPC 603 or 603e
4865 604 Motorola PowerPC 604 or 604e
4866 750 Motorola/IBM PowerPC 750 or 750
4868 At the moment, this command just tells GDB what to name the
4869 special-purpose processor registers. Since almost all the affected
4870 registers are inaccessible to user-level programs, this command is
4871 only useful for remote debugging in its present form.
4875 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4876 more extensive support for HP-UX. Added features include shared
4877 library support, kernel threads and hardware watchpoints for 11.00,
4878 support for HP's ANSI C and C++ compilers, and a compatibility mode
4879 for xdb and dbx commands.
4883 HP's donation includes the new concept of catchpoints, which is a
4884 generalization of the old catch command. On HP-UX, it is now possible
4885 to catch exec, fork, and vfork, as well as library loading.
4887 This means that the existing catch command has changed; its first
4888 argument now specifies the type of catch to be set up. See the
4889 output of "help catch" for a list of catchpoint types.
4891 * Debugging across forks
4893 On HP-UX, you can choose which process to debug when a fork() happens
4898 HP has donated a curses-based terminal user interface (TUI). To get
4899 it, build with --enable-tui. Although this can be enabled for any
4900 configuration, at present it only works for native HP debugging.
4902 * GDB remote protocol additions
4904 A new protocol packet 'X' that writes binary data is now available.
4905 Default behavior is to try 'X', then drop back to 'M' if the stub
4906 fails to respond. The settable variable `remotebinarydownload'
4907 allows explicit control over the use of 'X'.
4909 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4910 full 64-bit address. The command
4912 set remoteaddresssize 32
4914 can be used to revert to the old behaviour. For existing remote stubs
4915 the change should not be noticed, as the additional address information
4918 In order to assist in debugging stubs, you may use the maintenance
4919 command `packet' to send any text string to the stub. For instance,
4921 maint packet heythere
4923 sends the packet "$heythere#<checksum>". Note that it is very easy to
4924 disrupt a debugging session by sending the wrong packet at the wrong
4927 The compare-sections command allows you to compare section data on the
4928 target to what is in the executable file without uploading or
4929 downloading, by comparing CRC checksums.
4931 * Tracing can collect general expressions
4933 You may now collect general expressions at tracepoints. This requires
4934 further additions to the target-side stub; see tracepoint.c and
4935 doc/agentexpr.texi for further details.
4937 * mask-address variable for Mips
4939 For Mips targets, you may control the zeroing of the upper 32 bits of
4940 a 64-bit address by entering `set mask-address on'. This is mainly
4941 of interest to users of embedded R4xxx and R5xxx processors.
4943 * Higher serial baud rates
4945 GDB's serial code now allows you to specify baud rates 57600, 115200,
4946 230400, and 460800 baud. (Note that your host system may not be able
4947 to achieve all of these rates.)
4951 The i960 configuration now includes an initial implementation of a
4952 builtin simulator, contributed by Jim Wilson.
4955 *** Changes in GDB-4.17:
4957 * New native configurations
4959 Alpha GNU/Linux alpha*-*-linux*
4960 Unixware 2.x i[3456]86-unixware2*
4961 Irix 6.x mips*-sgi-irix6*
4962 PowerPC GNU/Linux powerpc-*-linux*
4963 PowerPC Solaris powerpcle-*-solaris*
4964 Sparc GNU/Linux sparc-*-linux*
4965 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4969 Argonaut Risc Chip (ARC) arc-*-*
4970 Hitachi H8/300S h8300*-*-*
4971 Matsushita MN10200 w/simulator mn10200-*-*
4972 Matsushita MN10300 w/simulator mn10300-*-*
4973 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4974 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4975 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4976 Mitsubishi D10V w/simulator d10v-*-*
4977 Mitsubishi M32R/D w/simulator m32r-*-elf*
4978 Tsqware Sparclet sparclet-*-*
4979 NEC V850 w/simulator v850-*-*
4981 * New debugging protocols
4983 ARM with RDI protocol arm*-*-*
4984 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4985 DDB and LSI variants of PMON protocol mips*-*-*
4986 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4987 PowerPC with SDS protocol powerpc{,le}-*-eabi
4988 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4992 All configurations can now understand and use the DWARF 2 debugging
4993 format. The choice is automatic, if the symbol file contains DWARF 2
4998 GDB now includes basic Java language support. This support is
4999 only useful with Java compilers that produce native machine code.
5001 * solib-absolute-prefix and solib-search-path
5003 For SunOS and SVR4 shared libraries, you may now set the prefix for
5004 loading absolute shared library symbol files, and the search path for
5005 locating non-absolute shared library symbol files.
5007 * Live range splitting
5009 GDB can now effectively debug code for which GCC has performed live
5010 range splitting as part of its optimization. See gdb/doc/LRS for
5011 more details on the expected format of the stabs information.
5015 GDB's support for the GNU Hurd, including thread debugging, has been
5016 updated to work with current versions of the Hurd.
5020 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5021 instruction set. ARM GDB automatically detects when Thumb
5022 instructions are in use, and adjusts disassembly and backtracing
5027 GDB's MIPS target configurations now handle the MIP16 16-bit
5032 GDB now includes support for overlays; if an executable has been
5033 linked such that multiple sections are based at the same address, GDB
5034 will decide which section to use for symbolic info. You can choose to
5035 control the decision manually, using overlay commands, or implement
5036 additional target-side support and use "overlay load-target" to bring
5037 in the overlay mapping. Do "help overlay" for more detail.
5041 The command "info symbol <address>" displays information about
5042 the symbol at the specified address.
5046 The standard remote protocol now includes an extension that allows
5047 asynchronous collection and display of trace data. This requires
5048 extensive support in the target-side debugging stub. Tracing mode
5049 includes a new interaction mode in GDB and new commands: see the
5050 file tracepoint.c for more details.
5054 Configurations for embedded MIPS now include a simulator contributed
5055 by Cygnus Solutions. The simulator supports the instruction sets
5056 of most MIPS variants.
5060 Sparc configurations may now include the ERC32 simulator contributed
5061 by the European Space Agency. The simulator is not built into
5062 Sparc targets by default; configure with --enable-sim to include it.
5066 For target configurations that may include multiple variants of a
5067 basic architecture (such as MIPS and SH), you may now set the
5068 architecture explicitly. "set arch" sets, "info arch" lists
5069 the possible architectures.
5071 *** Changes in GDB-4.16:
5073 * New native configurations
5075 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5076 M68K NetBSD m68k-*-netbsd*
5077 PowerPC AIX 4.x powerpc-*-aix*
5078 PowerPC MacOS powerpc-*-macos*
5079 PowerPC Windows NT powerpcle-*-cygwin32
5080 RS/6000 AIX 4.x rs6000-*-aix4*
5084 ARM with RDP protocol arm-*-*
5085 I960 with MON960 i960-*-coff
5086 MIPS VxWorks mips*-*-vxworks*
5087 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5088 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5090 Matra Sparclet sparclet-*-*
5094 The powerpc-eabi configuration now includes the PSIM simulator,
5095 contributed by Andrew Cagney, with assistance from Mike Meissner.
5096 PSIM is a very elaborate model of the PowerPC, including not only
5097 basic instruction set execution, but also details of execution unit
5098 performance and I/O hardware. See sim/ppc/README for more details.
5102 GDB now works with Solaris 2.5.
5104 * Windows 95/NT native
5106 GDB will now work as a native debugger on Windows 95 and Windows NT.
5107 To build it from source, you must use the "gnu-win32" environment,
5108 which uses a DLL to emulate enough of Unix to run the GNU tools.
5109 Further information, binaries, and sources are available at
5110 ftp.cygnus.com, under pub/gnu-win32.
5112 * dont-repeat command
5114 If a user-defined command includes the command `dont-repeat', then the
5115 command will not be repeated if the user just types return. This is
5116 useful if the command is time-consuming to run, so that accidental
5117 extra keystrokes don't run the same command many times.
5119 * Send break instead of ^C
5121 The standard remote protocol now includes an option to send a break
5122 rather than a ^C to the target in order to interrupt it. By default,
5123 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5125 * Remote protocol timeout
5127 The standard remote protocol includes a new variable `remotetimeout'
5128 that allows you to set the number of seconds before GDB gives up trying
5129 to read from the target. The default value is 2.
5131 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5133 By default GDB will automatically keep track of objects as they are
5134 loaded and unloaded by the dynamic linker. By using the command `set
5135 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5136 when shared library events occur, thus allowing you to set breakpoints
5137 in shared libraries which are explicitly loaded by the inferior.
5139 Note this feature does not work on hpux8. On hpux9 you must link
5140 /usr/lib/end.o into your program. This feature should work
5141 automatically on hpux10.
5143 * Irix 5.x hardware watchpoint support
5145 Irix 5 configurations now support the use of hardware watchpoints.
5147 * Mips protocol "SYN garbage limit"
5149 When debugging a Mips target using the `target mips' protocol, you
5150 may set the number of characters that GDB will ignore by setting
5151 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5152 every character. The default value is 1050.
5154 * Recording and replaying remote debug sessions
5156 If you set `remotelogfile' to the name of a file, gdb will write to it
5157 a recording of a remote debug session. This recording may then be
5158 replayed back to gdb using "gdbreplay". See gdbserver/README for
5159 details. This is useful when you have a problem with GDB while doing
5160 remote debugging; you can make a recording of the session and send it
5161 to someone else, who can then recreate the problem.
5163 * Speedups for remote debugging
5165 GDB includes speedups for downloading and stepping MIPS systems using
5166 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5167 and more efficient S-record downloading.
5169 * Memory use reductions and statistics collection
5171 GDB now uses less memory and reports statistics about memory usage.
5172 Try the `maint print statistics' command, for example.
5174 *** Changes in GDB-4.15:
5176 * Psymtabs for XCOFF
5178 The symbol reader for AIX GDB now uses partial symbol tables. This
5179 can greatly improve startup time, especially for large executables.
5181 * Remote targets use caching
5183 Remote targets now use a data cache to speed up communication with the
5184 remote side. The data cache could lead to incorrect results because
5185 it doesn't know about volatile variables, thus making it impossible to
5186 debug targets which use memory mapped I/O devices. `set remotecache
5187 off' turns the the data cache off.
5189 * Remote targets may have threads
5191 The standard remote protocol now includes support for multiple threads
5192 in the target system, using new protocol commands 'H' and 'T'. See
5193 gdb/remote.c for details.
5197 If GDB is configured with `--enable-netrom', then it will include
5198 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5199 acts as though it is a bank of ROM on the target board, but you can
5200 write into it over the network. GDB's support consists only of
5201 support for fast loading into the emulated ROM; to debug, you must use
5202 another protocol, such as standard remote protocol. The usual
5203 sequence is something like
5205 target nrom <netrom-hostname>
5207 target remote <netrom-hostname>:1235
5211 GDB now includes support for the Apple Macintosh, as a host only. It
5212 may be run as either an MPW tool or as a standalone application, and
5213 it can debug through the serial port. All the usual GDB commands are
5214 available, but to the target command, you must supply "serial" as the
5215 device type instead of "/dev/ttyXX". See mpw-README in the main
5216 directory for more information on how to build. The MPW configuration
5217 scripts */mpw-config.in support only a few targets, and only the
5218 mips-idt-ecoff target has been tested.
5222 GDB configuration now uses autoconf. This is not user-visible,
5223 but does simplify configuration and building.
5227 GDB now supports hpux10.
5229 *** Changes in GDB-4.14:
5231 * New native configurations
5233 x86 FreeBSD i[345]86-*-freebsd
5234 x86 NetBSD i[345]86-*-netbsd
5235 NS32k NetBSD ns32k-*-netbsd
5236 Sparc NetBSD sparc-*-netbsd
5240 A29K VxWorks a29k-*-vxworks
5241 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5242 CPU32 EST-300 emulator m68*-*-est*
5243 PowerPC ELF powerpc-*-elf
5246 * Alpha OSF/1 support for procfs
5248 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5249 possible to attach to running processes. As the mounting of the /proc
5250 filesystem is optional on the Alpha, GDB automatically determines
5251 the availability of /proc during startup. This can lead to problems
5252 if /proc is unmounted after GDB has been started.
5254 * Arguments to user-defined commands
5256 User commands may accept up to 10 arguments separated by whitespace.
5257 Arguments are accessed within the user command via $arg0..$arg9. A
5260 print $arg0 + $arg1 + $arg2
5262 To execute the command use:
5265 Defines the command "adder" which prints the sum of its three arguments.
5266 Note the arguments are text substitutions, so they may reference variables,
5267 use complex expressions, or even perform inferior function calls.
5269 * New `if' and `while' commands
5271 This makes it possible to write more sophisticated user-defined
5272 commands. Both commands take a single argument, which is the
5273 expression to evaluate, and must be followed by the commands to
5274 execute, one per line, if the expression is nonzero, the list being
5275 terminated by the word `end'. The `if' command list may include an
5276 `else' word, which causes the following commands to be executed only
5277 if the expression is zero.
5279 * Fortran source language mode
5281 GDB now includes partial support for Fortran 77. It will recognize
5282 Fortran programs and can evaluate a subset of Fortran expressions, but
5283 variables and functions may not be handled correctly. GDB will work
5284 with G77, but does not yet know much about symbols emitted by other
5287 * Better HPUX support
5289 Most debugging facilities now work on dynamic executables for HPPAs
5290 running hpux9 or later. You can attach to running dynamically linked
5291 processes, but by default the dynamic libraries will be read-only, so
5292 for instance you won't be able to put breakpoints in them. To change
5293 that behavior do the following before running the program:
5299 This will cause the libraries to be mapped private and read-write.
5300 To revert to the normal behavior, do this:
5306 You cannot set breakpoints or examine data in the library until after
5307 the library is loaded if the function/data symbols do not have
5310 GDB can now also read debug symbols produced by the HP C compiler on
5311 HPPAs (sorry, no C++, Fortran or 68k support).
5313 * Target byte order now dynamically selectable
5315 You can choose which byte order to use with a target system, via the
5316 commands "set endian big" and "set endian little", and you can see the
5317 current setting by using "show endian". You can also give the command
5318 "set endian auto", in which case GDB will use the byte order
5319 associated with the executable. Currently, only embedded MIPS
5320 configurations support dynamic selection of target byte order.
5322 * New DOS host serial code
5324 This version uses DPMI interrupts to handle buffered I/O, so you
5325 no longer need to run asynctsr when debugging boards connected to
5328 *** Changes in GDB-4.13:
5330 * New "complete" command
5332 This lists all the possible completions for the rest of the line, if it
5333 were to be given as a command itself. This is intended for use by emacs.
5335 * Trailing space optional in prompt
5337 "set prompt" no longer adds a space for you after the prompt you set. This
5338 allows you to set a prompt which ends in a space or one that does not.
5340 * Breakpoint hit counts
5342 "info break" now displays a count of the number of times the breakpoint
5343 has been hit. This is especially useful in conjunction with "ignore"; you
5344 can ignore a large number of breakpoint hits, look at the breakpoint info
5345 to see how many times the breakpoint was hit, then run again, ignoring one
5346 less than that number, and this will get you quickly to the last hit of
5349 * Ability to stop printing at NULL character
5351 "set print null-stop" will cause GDB to stop printing the characters of
5352 an array when the first NULL is encountered. This is useful when large
5353 arrays actually contain only short strings.
5355 * Shared library breakpoints
5357 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5358 breakpoints in shared libraries before the executable is run.
5360 * Hardware watchpoints
5362 There is a new hardware breakpoint for the watch command for sparclite
5363 targets. See gdb/sparclite/hw_breakpoint.note.
5365 Hardware watchpoints are also now supported under GNU/Linux.
5369 Annotations have been added. These are for use with graphical interfaces,
5370 and are still experimental. Currently only gdba.el uses these.
5372 * Improved Irix 5 support
5374 GDB now works properly with Irix 5.2.
5376 * Improved HPPA support
5378 GDB now works properly with the latest GCC and GAS.
5380 * New native configurations
5382 Sequent PTX4 i[34]86-sequent-ptx4
5383 HPPA running OSF/1 hppa*-*-osf*
5384 Atari TT running SVR4 m68*-*-sysv4*
5385 RS/6000 LynxOS rs6000-*-lynxos*
5389 OS/9000 i[34]86-*-os9k
5390 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5393 * Hitachi SH7000 and E7000-PC ICE support
5395 There is now support for communicating with the Hitachi E7000-PC ICE.
5396 This is available automatically when GDB is configured for the SH.
5400 As usual, a variety of small fixes and improvements, both generic
5401 and configuration-specific. See the ChangeLog for more detail.
5403 *** Changes in GDB-4.12:
5405 * Irix 5 is now supported
5409 GDB-4.12 on the HPPA has a number of changes which make it unable
5410 to debug the output from the currently released versions of GCC and
5411 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5412 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5413 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5416 *** Changes in GDB-4.11:
5418 * User visible changes:
5422 The "set remotedebug" option is now consistent between the mips remote
5423 target, remote targets using the gdb-specific protocol, UDI (AMD's
5424 debug protocol for the 29k) and the 88k bug monitor. It is now an
5425 integer specifying a debug level (normally 0 or 1, but 2 means more
5426 debugging info for the mips target).
5428 * DEC Alpha native support
5430 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5431 debug info, but GDB works fairly well with the DEC compiler and should
5432 work with a future GCC release. See the README file for a few
5433 Alpha-specific notes.
5435 * Preliminary thread implementation
5437 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5439 * LynxOS native and target support for 386
5441 This release has been hosted on LynxOS 2.2, and also can be configured
5442 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5445 * Improvements in C++ mangling/demangling.
5447 This release has much better g++ debugging, specifically in name
5448 mangling/demangling, virtual function calls, print virtual table,
5449 call methods, ...etc.
5451 *** Changes in GDB-4.10:
5453 * User visible changes:
5455 Remote debugging using the GDB-specific (`target remote') protocol now
5456 supports the `load' command. This is only useful if you have some
5457 other way of getting the stub to the target system, and you can put it
5458 somewhere in memory where it won't get clobbered by the download.
5460 Filename completion now works.
5462 When run under emacs mode, the "info line" command now causes the
5463 arrow to point to the line specified. Also, "info line" prints
5464 addresses in symbolic form (as well as hex).
5466 All vxworks based targets now support a user settable option, called
5467 vxworks-timeout. This option represents the number of seconds gdb
5468 should wait for responses to rpc's. You might want to use this if
5469 your vxworks target is, perhaps, a slow software simulator or happens
5470 to be on the far side of a thin network line.
5474 This release contains support for using a DEC alpha as a GDB host for
5475 cross debugging. Native alpha debugging is not supported yet.
5478 *** Changes in GDB-4.9:
5482 This is the first GDB release which is accompanied by a matching testsuite.
5483 The testsuite requires installation of dejagnu, which should be available
5484 via ftp from most sites that carry GNU software.
5488 'Cfront' style demangling has had its name changed to 'ARM' style, to
5489 emphasize that it was written from the specifications in the C++ Annotated
5490 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5491 disclaimers, it still generated too much confusion with users attempting to
5492 use gdb with AT&T cfront.
5496 GDB now uses a standard remote interface to a simulator library.
5497 So far, the library contains simulators for the Zilog Z8001/2, the
5498 Hitachi H8/300, H8/500 and Super-H.
5500 * New targets supported
5502 H8/300 simulator h8300-hitachi-hms or h8300hms
5503 H8/500 simulator h8500-hitachi-hms or h8500hms
5504 SH simulator sh-hitachi-hms or sh
5505 Z8000 simulator z8k-zilog-none or z8ksim
5506 IDT MIPS board over serial line mips-idt-ecoff
5508 Cross-debugging to GO32 targets is supported. It requires a custom
5509 version of the i386-stub.c module which is integrated with the
5510 GO32 memory extender.
5512 * New remote protocols
5514 MIPS remote debugging protocol.
5516 * New source languages supported
5518 This version includes preliminary support for Chill, a Pascal like language
5519 used by telecommunications companies. Chill support is also being integrated
5520 into the GNU compiler, but we don't know when it will be publically available.
5523 *** Changes in GDB-4.8:
5525 * HP Precision Architecture supported
5527 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5528 version of this support was available as a set of patches from the
5529 University of Utah. GDB does not support debugging of programs
5530 compiled with the HP compiler, because HP will not document their file
5531 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5532 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5534 Many problems in the preliminary version have been fixed.
5536 * Faster and better demangling
5538 We have improved template demangling and fixed numerous bugs in the GNU style
5539 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5540 character types (wchar_t) are now supported. Demangling of each symbol is now
5541 only done once, and is cached when the symbol table for a file is read in.
5542 This results in a small increase in memory usage for C programs, a moderate
5543 increase in memory usage for C++ programs, and a fantastic speedup in
5546 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5547 from the specifications in the Annotated Reference Manual, which AT&T's
5548 compiler does not actually implement.
5550 * G++ multiple inheritance compiler problem
5552 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5553 inheritance lattices was reworked to properly discover ambiguities. We
5554 recently found an example which causes this new algorithm to fail in a
5555 very subtle way, producing bad debug information for those classes.
5556 The file 'gcc.patch' (in this directory) can be applied to gcc to
5557 circumvent the problem. A future GCC release will contain a complete
5560 The previous G++ debug info problem (mentioned below for the gdb-4.7
5561 release) is fixed in gcc version 2.3.2.
5563 * Improved configure script
5565 The `configure' script will now attempt to guess your system type if
5566 you don't supply a host system type. The old scheme of supplying a
5567 host system triplet is preferable over using this. All the magic is
5568 done in the new `config.guess' script. Examine it for details.
5570 We have also brought our configure script much more in line with the FSF's
5571 version. It now supports the --with-xxx options. In particular,
5572 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5573 The resulting GDB will not be able to read arbitrary object file formats --
5574 only the format ``expected'' to be used on the configured target system.
5575 We hope to make this the default in a future release.
5577 * Documentation improvements
5579 There's new internal documentation on how to modify GDB, and how to
5580 produce clean changes to the code. We implore people to read it
5581 before submitting changes.
5583 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5584 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5585 `info' files are also provided. To build `info' files from scratch,
5586 you will need the latest `makeinfo' release, which will be available in
5587 a future texinfo-X.Y release.
5589 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5590 We're not sure exactly which versions have this problem, but it has
5591 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5592 or better. If that isn't possible, there is a patch in
5593 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5594 around this problem.
5598 GDB now supports array constants that can be used in expressions typed in by
5599 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5600 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5603 The new directory `gdb/sparclite' contains a program that demonstrates
5604 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5606 * New native hosts supported
5608 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5609 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5611 * New targets supported
5613 AMD 29k family via UDI a29k-amd-udi or udi29k
5615 * New file formats supported
5617 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5618 HPUX core files, and SCO 3.2v2 core files.
5622 Attaching to processes now works again; thanks for the many bug reports.
5624 We have also stomped on a bunch of core dumps caused by
5625 printf_filtered("%s") problems.
5627 We eliminated a copyright problem on the rpc and ptrace header files
5628 for VxWorks, which was discovered at the last minute during the 4.7
5629 release. You should now be able to build a VxWorks GDB.
5631 You can now interrupt gdb while an attached process is running. This
5632 will cause the attached process to stop, and give control back to GDB.
5634 We fixed problems caused by using too many file descriptors
5635 for reading symbols from object files and libraries. This was
5636 especially a problem for programs that used many (~100) shared
5639 The `step' command now only enters a subroutine if there is line number
5640 information for the subroutine. Otherwise it acts like the `next'
5641 command. Previously, `step' would enter subroutines if there was
5642 any debugging information about the routine. This avoids problems
5643 when using `cc -g1' on MIPS machines.
5645 * Internal improvements
5647 GDB's internal interfaces have been improved to make it easier to support
5648 debugging of multiple languages in the future.
5650 GDB now uses a common structure for symbol information internally.
5651 Minimal symbols (derived from linkage symbols in object files), partial
5652 symbols (from a quick scan of debug information), and full symbols
5653 contain a common subset of information, making it easier to write
5654 shared code that handles any of them.
5656 * New command line options
5658 We now accept --silent as an alias for --quiet.
5662 The memory-mapped-malloc library is now licensed under the GNU Library
5663 General Public License.
5665 *** Changes in GDB-4.7:
5667 * Host/native/target split
5669 GDB has had some major internal surgery to untangle the support for
5670 hosts and remote targets. Now, when you configure GDB for a remote
5671 target, it will no longer load in all of the support for debugging
5672 local programs on the host. When fully completed and tested, this will
5673 ensure that arbitrary host/target combinations are possible.
5675 The primary conceptual shift is to separate the non-portable code in
5676 GDB into three categories. Host specific code is required any time GDB
5677 is compiled on that host, regardless of the target. Target specific
5678 code relates to the peculiarities of the target, but can be compiled on
5679 any host. Native specific code is everything else: it can only be
5680 built when the host and target are the same system. Child process
5681 handling and core file support are two common `native' examples.
5683 GDB's use of /proc for controlling Unix child processes is now cleaner.
5684 It has been split out into a single module under the `target_ops' vector,
5685 plus two native-dependent functions for each system that uses /proc.
5687 * New hosts supported
5689 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5690 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5691 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5693 * New targets supported
5695 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5696 68030 and CPU32 m68030-*-*, m68332-*-*
5698 * New native hosts supported
5700 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5701 (386bsd is not well tested yet)
5702 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5704 * New file formats supported
5706 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5707 supports reading of `a.out.adobe' object files, which are an a.out
5708 format extended with minimal information about multiple sections.
5712 `show copying' is the same as the old `info copying'.
5713 `show warranty' is the same as `info warrantee'.
5714 These were renamed for consistency. The old commands continue to work.
5716 `info handle' is a new alias for `info signals'.
5718 You can now define pre-command hooks, which attach arbitrary command
5719 scripts to any command. The commands in the hook will be executed
5720 prior to the user's command. You can also create a hook which will be
5721 executed whenever the program stops. See gdb.texinfo.
5725 We now deal with Cfront style name mangling, and can even extract type
5726 info from mangled symbols. GDB can automatically figure out which
5727 symbol mangling style your C++ compiler uses.
5729 Calling of methods and virtual functions has been improved as well.
5733 The crash that occured when debugging Sun Ansi-C compiled binaries is
5734 fixed. This was due to mishandling of the extra N_SO stabs output
5737 We also finally got Ultrix 4.2 running in house, and fixed core file
5738 support, with help from a dozen people on the net.
5740 John M. Farrell discovered that the reason that single-stepping was so
5741 slow on all of the Mips based platforms (primarily SGI and DEC) was
5742 that we were trying to demangle and lookup a symbol used for internal
5743 purposes on every instruction that was being stepped through. Changing
5744 the name of that symbol so that it couldn't be mistaken for a C++
5745 mangled symbol sped things up a great deal.
5747 Rich Pixley sped up symbol lookups in general by getting much smarter
5748 about when C++ symbol mangling is necessary. This should make symbol
5749 completion (TAB on the command line) much faster. It's not as fast as
5750 we'd like, but it's significantly faster than gdb-4.6.
5754 A new user controllable variable 'call_scratch_address' can
5755 specify the location of a scratch area to be used when GDB
5756 calls a function in the target. This is necessary because the
5757 usual method of putting the scratch area on the stack does not work
5758 in systems that have separate instruction and data spaces.
5760 We integrated changes to support the 29k UDI (Universal Debugger
5761 Interface), but discovered at the last minute that we didn't have all
5762 of the appropriate copyright paperwork. We are working with AMD to
5763 resolve this, and hope to have it available soon.
5767 We have sped up the remote serial line protocol, especially for targets
5768 with lots of registers. It now supports a new `expedited status' ('T')
5769 message which can be used in place of the existing 'S' status message.
5770 This allows the remote stub to send only the registers that GDB
5771 needs to make a quick decision about single-stepping or conditional
5772 breakpoints, eliminating the need to fetch the entire register set for
5773 each instruction being stepped through.
5775 The GDB remote serial protocol now implements a write-through cache for
5776 registers, only re-reading the registers if the target has run.
5778 There is also a new remote serial stub for SPARC processors. You can
5779 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5780 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5781 processor with a serial port.
5785 Configure.in files have become much easier to read and modify. A new
5786 `table driven' format makes it more obvious what configurations are
5787 supported, and what files each one uses.
5791 There is a new opcodes library which will eventually contain all of the
5792 disassembly routines and opcode tables. At present, it only contains
5793 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5794 disassembler (binutils/objdump) to share these routines.
5796 The libiberty library is now copylefted under the GNU Library General
5797 Public License. This allows more liberal use, and was done so libg++
5798 can use it. This makes no difference to GDB, since the Library License
5799 grants all the rights from the General Public License.
5803 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5804 reference to the stabs symbol info used by the debugger. It is (as far
5805 as we know) the only published document on this fascinating topic. We
5806 encourage you to read it, compare it to the stabs information on your
5807 system, and send improvements on the document in general (to
5808 bug-gdb@prep.ai.mit.edu).
5810 And, of course, many bugs have been fixed.
5813 *** Changes in GDB-4.6:
5815 * Better support for C++ function names
5817 GDB now accepts as input the "demangled form" of C++ overloaded function
5818 names and member function names, and can do command completion on such names
5819 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5820 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5821 Make use of command completion, it is your friend.
5823 GDB also now accepts a variety of C++ mangled symbol formats. They are
5824 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5825 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5826 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5827 for the list of formats.
5829 * G++ symbol mangling problem
5831 Recent versions of gcc have a bug in how they emit debugging information for
5832 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5833 directory) can be applied to gcc to fix the problem. Alternatively, if you
5834 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5835 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5836 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5839 * New 'maintenance' command
5841 All of the commands related to hacking GDB internals have been moved out of
5842 the main command set, and now live behind the 'maintenance' command. This
5843 can also be abbreviated as 'mt'. The following changes were made:
5845 dump-me -> maintenance dump-me
5846 info all-breakpoints -> maintenance info breakpoints
5847 printmsyms -> maintenance print msyms
5848 printobjfiles -> maintenance print objfiles
5849 printpsyms -> maintenance print psymbols
5850 printsyms -> maintenance print symbols
5852 The following commands are new:
5854 maintenance demangle Call internal GDB demangler routine to
5855 demangle a C++ link name and prints the result.
5856 maintenance print type Print a type chain for a given symbol
5858 * Change to .gdbinit file processing
5860 We now read the $HOME/.gdbinit file before processing the argv arguments
5861 (e.g. reading symbol files or core files). This allows global parameters to
5862 be set, which will apply during the symbol reading. The ./.gdbinit is still
5863 read after argv processing.
5865 * New hosts supported
5867 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5869 GNU/Linux support i386-unknown-linux or linux
5871 We are also including code to support the HP/PA running BSD and HPUX. This
5872 is almost guaranteed not to work, as we didn't have time to test or build it
5873 for this release. We are including it so that the more adventurous (or
5874 masochistic) of you can play with it. We also had major problems with the
5875 fact that the compiler that we got from HP doesn't support the -g option.
5878 * New targets supported
5880 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5882 * More smarts about finding #include files
5884 GDB now remembers the compilation directory for all include files, and for
5885 all files from which C is generated (like yacc and lex sources). This
5886 greatly improves GDB's ability to find yacc/lex sources, and include files,
5887 especially if you are debugging your program from a directory different from
5888 the one that contains your sources.
5890 We also fixed a bug which caused difficulty with listing and setting
5891 breakpoints in include files which contain C code. (In the past, you had to
5892 try twice in order to list an include file that you hadn't looked at before.)
5894 * Interesting infernals change
5896 GDB now deals with arbitrary numbers of sections, where the symbols for each
5897 section must be relocated relative to that section's landing place in the
5898 target's address space. This work was needed to support ELF with embedded
5899 stabs used by Solaris-2.0.
5901 * Bug fixes (of course!)
5903 There have been loads of fixes for the following things:
5904 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5905 i960, stabs, DOS(GO32), procfs, etc...
5907 See the ChangeLog for details.
5909 *** Changes in GDB-4.5:
5911 * New machines supported (host and target)
5913 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5915 SGI Irix-4.x mips-sgi-irix4 or iris4
5917 * New malloc package
5919 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5920 Mmalloc is capable of handling mutiple heaps of memory. It is also
5921 capable of saving a heap to a file, and then mapping it back in later.
5922 This can be used to greatly speedup the startup of GDB by using a
5923 pre-parsed symbol table which lives in a mmalloc managed heap. For
5924 more details, please read mmalloc/mmalloc.texi.
5928 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5929 'help info proc' for details.
5931 * MIPS ecoff symbol table format
5933 The code that reads MIPS symbol table format is now supported on all hosts.
5934 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5937 * File name changes for MS-DOS
5939 Many files in the config directories have been renamed to make it easier to
5940 support GDB on MS-DOSe systems (which have very restrictive file name
5941 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5942 environment) is close to working but has some remaining problems. Note
5943 that debugging of DOS programs is not supported, due to limitations
5944 in the ``operating system'', but it can be used to host cross-debugging.
5946 * Cross byte order fixes
5948 Many fixes have been made to support cross debugging of Sparc and MIPS
5949 targets from hosts whose byte order differs.
5951 * New -mapped and -readnow options
5953 If memory-mapped files are available on your system through the 'mmap'
5954 system call, you can use the -mapped option on the `file' or
5955 `symbol-file' commands to cause GDB to write the symbols from your
5956 program into a reusable file. If the program you are debugging is
5957 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5958 Future GDB debugging sessions will notice the presence of this file,
5959 and will quickly map in symbol information from it, rather than reading
5960 the symbol table from the executable program. Using the '-mapped'
5961 option in a GDB `file' or `symbol-file' command has the same effect as
5962 starting GDB with the '-mapped' command-line option.
5964 You can cause GDB to read the entire symbol table immediately by using
5965 the '-readnow' option with any of the commands that load symbol table
5966 information (or on the GDB command line). This makes the command
5967 slower, but makes future operations faster.
5969 The -mapped and -readnow options are typically combined in order to
5970 build a `fred.syms' file that contains complete symbol information.
5971 A simple GDB invocation to do nothing but build a `.syms' file for future
5974 gdb -batch -nx -mapped -readnow programname
5976 The `.syms' file is specific to the host machine on which GDB is run.
5977 It holds an exact image of GDB's internal symbol table. It cannot be
5978 shared across multiple host platforms.
5980 * longjmp() handling
5982 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5983 siglongjmp() without losing control. This feature has not yet been ported to
5984 all systems. It currently works on many 386 platforms, all MIPS-based
5985 platforms (SGI, DECstation, etc), and Sun3/4.
5989 Preliminary work has been put in to support the new Solaris OS from Sun. At
5990 this time, it can control and debug processes, but it is not capable of
5995 As always, many many bug fixes. The major areas were with g++, and mipsread.
5996 People using the MIPS-based platforms should experience fewer mysterious
5997 crashes and trashed symbol tables.
5999 *** Changes in GDB-4.4:
6001 * New machines supported (host and target)
6003 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6005 BSD Reno on Vax vax-dec-bsd
6006 Ultrix on Vax vax-dec-ultrix
6008 * New machines supported (target)
6010 AMD 29000 embedded, using EBMON a29k-none-none
6014 GDB continues to improve its handling of C++. `References' work better.
6015 The demangler has also been improved, and now deals with symbols mangled as
6016 per the Annotated C++ Reference Guide.
6018 GDB also now handles `stabs' symbol information embedded in MIPS
6019 `ecoff' symbol tables. Since the ecoff format was not easily
6020 extensible to handle new languages such as C++, this appeared to be a
6021 good way to put C++ debugging info into MIPS binaries. This option
6022 will be supported in the GNU C compiler, version 2, when it is
6025 * New features for SVR4
6027 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6028 shared libraries. Debugging dynamically linked programs should present
6029 only minor differences from debugging statically linked programs.
6031 The `info proc' command will print out information about any process
6032 on an SVR4 system (including the one you are debugging). At the moment,
6033 it prints the address mappings of the process.
6035 If you bring up GDB on another SVR4 system, please send mail to
6036 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6038 * Better dynamic linking support in SunOS
6040 Reading symbols from shared libraries which contain debugging symbols
6041 now works properly. However, there remain issues such as automatic
6042 skipping of `transfer vector' code during function calls, which
6043 make it harder to debug code in a shared library, than to debug the
6044 same code linked statically.
6048 GDB is now using the latest `getopt' routines from the FSF. This
6049 version accepts the -- prefix for options with long names. GDB will
6050 continue to accept the old forms (-option and +option) as well.
6051 Various single letter abbreviations for options have been explicity
6052 added to the option table so that they won't get overshadowed in the
6053 future by other options that begin with the same letter.
6057 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6058 Many assorted bugs have been handled. Many more remain to be handled.
6059 See the various ChangeLog files (primarily in gdb and bfd) for details.
6062 *** Changes in GDB-4.3:
6064 * New machines supported (host and target)
6066 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6067 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6068 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6070 * Almost SCO Unix support
6072 We had hoped to support:
6073 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6074 (except for core file support), but we discovered very late in the release
6075 that it has problems with process groups that render gdb unusable. Sorry
6076 about that. I encourage people to fix it and post the fixes.
6078 * Preliminary ELF and DWARF support
6080 GDB can read ELF object files on System V Release 4, and can handle
6081 debugging records for C, in DWARF format, in ELF files. This support
6082 is preliminary. If you bring up GDB on another SVR4 system, please
6083 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6088 GDB now uses the latest `readline' library. One user-visible change
6089 is that two tabs will list possible command completions, which previously
6090 required typing M-? (meta-question mark, or ESC ?).
6094 The `stepi' bug that many of you noticed has been squashed.
6095 Many bugs in C++ have been handled. Many more remain to be handled.
6096 See the various ChangeLog files (primarily in gdb and bfd) for details.
6098 * State of the MIPS world (in case you wondered):
6100 GDB can understand the symbol tables emitted by the compilers
6101 supplied by most vendors of MIPS-based machines, including DEC. These
6102 symbol tables are in a format that essentially nobody else uses.
6104 Some versions of gcc come with an assembler post-processor called
6105 mips-tfile. This program is required if you want to do source-level
6106 debugging of gcc-compiled programs. I believe FSF does not ship
6107 mips-tfile with gcc version 1, but it will eventually come with gcc
6110 Debugging of g++ output remains a problem. g++ version 1.xx does not
6111 really support it at all. (If you're lucky, you should be able to get
6112 line numbers and stack traces to work, but no parameters or local
6113 variables.) With some work it should be possible to improve the
6116 When gcc version 2 is released, you will have somewhat better luck.
6117 However, even then you will get confusing results for inheritance and
6120 We will eventually provide full debugging of g++ output on
6121 DECstations. This will probably involve some kind of stabs-in-ecoff
6122 encapulation, but the details have not been worked out yet.
6125 *** Changes in GDB-4.2:
6127 * Improved configuration
6129 Only one copy of `configure' exists now, and it is not self-modifying.
6130 Porting BFD is simpler.
6134 The `step' and `next' commands now only stop at the first instruction
6135 of a source line. This prevents the multiple stops that used to occur
6136 in switch statements, for-loops, etc. `Step' continues to stop if a
6137 function that has debugging information is called within the line.
6141 Lots of small bugs fixed. More remain.
6143 * New host supported (not target)
6145 Intel 386 PC clone running Mach i386-none-mach
6148 *** Changes in GDB-4.1:
6150 * Multiple source language support
6152 GDB now has internal scaffolding to handle several source languages.
6153 It determines the type of each source file from its filename extension,
6154 and will switch expression parsing and number formatting to match the
6155 language of the function in the currently selected stack frame.
6156 You can also specifically set the language to be used, with
6157 `set language c' or `set language modula-2'.
6161 GDB now has preliminary support for the GNU Modula-2 compiler,
6162 currently under development at the State University of New York at
6163 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6164 continue through the fall of 1991 and into 1992.
6166 Other Modula-2 compilers are currently not supported, and attempting to
6167 debug programs compiled with them will likely result in an error as the
6168 symbol table is read. Feel free to work on it, though!
6170 There are hooks in GDB for strict type checking and range checking,
6171 in the `Modula-2 philosophy', but they do not currently work.
6175 GDB can now write to executable and core files (e.g. patch
6176 a variable's value). You must turn this switch on, specify
6177 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6178 by assigning a new value to a variable. Modifications take
6181 * Automatic SunOS shared library reading
6183 When you run your program, GDB automatically determines where its
6184 shared libraries (if any) have been loaded, and reads their symbols.
6185 The `share' command is no longer needed. This also works when
6186 examining core files.
6190 You can specify the number of lines that the `list' command shows.
6193 * New machines supported (host and target)
6195 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6196 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6197 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6199 * New hosts supported (not targets)
6201 IBM RT/PC: romp-ibm-aix or rtpc
6203 * New targets supported (not hosts)
6205 AMD 29000 embedded with COFF a29k-none-coff
6206 AMD 29000 embedded with a.out a29k-none-aout
6207 Ultracomputer remote kernel debug a29k-nyu-kern
6209 * New remote interfaces
6215 *** Changes in GDB-4.0:
6219 Wide output is wrapped at good places to make the output more readable.
6221 Gdb now supports cross-debugging from a host machine of one type to a
6222 target machine of another type. Communication with the target system
6223 is over serial lines. The ``target'' command handles connecting to the
6224 remote system; the ``load'' command will download a program into the
6225 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6226 also supports debugging of realtime processes running under VxWorks,
6227 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6228 stub on the target system.
6230 New CPUs supported include the AMD 29000 and Intel 960.
6232 GDB now reads object files and symbol tables via a ``binary file''
6233 library, which allows a single copy of GDB to debug programs of multiple
6234 object file types such as a.out and coff.
6236 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6237 refcard.dvi and refcard.ps are available to format it).
6240 * Control-Variable user interface simplified
6242 All variables that control the operation of the debugger can be set
6243 by the ``set'' command, and displayed by the ``show'' command.
6245 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6246 ``Show prompt'' produces the response:
6247 Gdb's prompt is new-gdb=>.
6249 What follows are the NEW set commands. The command ``help set'' will
6250 print a complete list of old and new set commands. ``help set FOO''
6251 will give a longer description of the variable FOO. ``show'' will show
6252 all of the variable descriptions and their current settings.
6254 confirm on/off: Enables warning questions for operations that are
6255 hard to recover from, e.g. rerunning the program while
6256 it is already running. Default is ON.
6258 editing on/off: Enables EMACS style command line editing
6259 of input. Previous lines can be recalled with
6260 control-P, the current line can be edited with control-B,
6261 you can search for commands with control-R, etc.
6264 history filename NAME: NAME is where the gdb command history
6265 will be stored. The default is .gdb_history,
6266 or the value of the environment variable
6269 history size N: The size, in commands, of the command history. The
6270 default is 256, or the value of the environment variable
6273 history save on/off: If this value is set to ON, the history file will
6274 be saved after exiting gdb. If set to OFF, the
6275 file will not be saved. The default is OFF.
6277 history expansion on/off: If this value is set to ON, then csh-like
6278 history expansion will be performed on
6279 command line input. The default is OFF.
6281 radix N: Sets the default radix for input and output. It can be set
6282 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6283 in the current radix, so "set radix 10" is always a no-op.
6285 height N: This integer value is the number of lines on a page. Default
6286 is 24, the current `stty rows'' setting, or the ``li#''
6287 setting from the termcap entry matching the environment
6290 width N: This integer value is the number of characters on a line.
6291 Default is 80, the current `stty cols'' setting, or the ``co#''
6292 setting from the termcap entry matching the environment
6295 Note: ``set screensize'' is obsolete. Use ``set height'' and
6296 ``set width'' instead.
6298 print address on/off: Print memory addresses in various command displays,
6299 such as stack traces and structure values. Gdb looks
6300 more ``symbolic'' if you turn this off; it looks more
6301 ``machine level'' with it on. Default is ON.
6303 print array on/off: Prettyprint arrays. New convenient format! Default
6306 print demangle on/off: Print C++ symbols in "source" form if on,
6309 print asm-demangle on/off: Same, for assembler level printouts
6312 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6315 * Support for Epoch Environment.
6317 The epoch environment is a version of Emacs v18 with windowing. One
6318 new command, ``inspect'', is identical to ``print'', except that if you
6319 are running in the epoch environment, the value is printed in its own
6323 * Support for Shared Libraries
6325 GDB can now debug programs and core files that use SunOS shared libraries.
6326 Symbols from a shared library cannot be referenced
6327 before the shared library has been linked with the program (this
6328 happens after you type ``run'' and before the function main() is entered).
6329 At any time after this linking (including when examining core files
6330 from dynamically linked programs), gdb reads the symbols from each
6331 shared library when you type the ``sharedlibrary'' command.
6332 It can be abbreviated ``share''.
6334 sharedlibrary REGEXP: Load shared object library symbols for files
6335 matching a unix regular expression. No argument
6336 indicates to load symbols for all shared libraries.
6338 info sharedlibrary: Status of loaded shared libraries.
6343 A watchpoint stops execution of a program whenever the value of an
6344 expression changes. Checking for this slows down execution
6345 tremendously whenever you are in the scope of the expression, but is
6346 quite useful for catching tough ``bit-spreader'' or pointer misuse
6347 problems. Some machines such as the 386 have hardware for doing this
6348 more quickly, and future versions of gdb will use this hardware.
6350 watch EXP: Set a watchpoint (breakpoint) for an expression.
6352 info watchpoints: Information about your watchpoints.
6354 delete N: Deletes watchpoint number N (same as breakpoints).
6355 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6356 enable N: Re-enables watchpoint number N (same as breakpoints).
6359 * C++ multiple inheritance
6361 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6364 * C++ exception handling
6366 Gdb now supports limited C++ exception handling. Besides the existing
6367 ability to breakpoint on an exception handler, gdb can breakpoint on
6368 the raising of an exception (before the stack is peeled back to the
6371 catch FOO: If there is a FOO exception handler in the dynamic scope,
6372 set a breakpoint to catch exceptions which may be raised there.
6373 Multiple exceptions (``catch foo bar baz'') may be caught.
6375 info catch: Lists all exceptions which may be caught in the
6376 current stack frame.
6379 * Minor command changes
6381 The command ``call func (arg, arg, ...)'' now acts like the print
6382 command, except it does not print or save a value if the function's result
6383 is void. This is similar to dbx usage.
6385 The ``up'' and ``down'' commands now always print the frame they end up
6386 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6387 frames without printing.
6389 * New directory command
6391 'dir' now adds directories to the FRONT of the source search path.
6392 The path starts off empty. Source files that contain debug information
6393 about the directory in which they were compiled can be found even
6394 with an empty path; Sun CC and GCC include this information. If GDB can't
6395 find your source file in the current directory, type "dir .".
6397 * Configuring GDB for compilation
6399 For normal use, type ``./configure host''. See README or gdb.texinfo
6402 GDB now handles cross debugging. If you are remotely debugging between
6403 two different machines, type ``./configure host -target=targ''.
6404 Host is the machine where GDB will run; targ is the machine
6405 where the program that you are debugging will run.
projects / external / binutils.git / blob