1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.10
6 * GDB now supports debugging kernel-based threads on FreeBSD.
8 * Per-inferior thread numbers
10 Thread numbers are now per inferior instead of global. If you're
11 debugging multiple inferiors, GDB displays thread IDs using a
12 qualified INF_NUM.THR_NUM form. For example:
16 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
17 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
18 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
19 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
21 As consequence, thread numbers as visible in the $_thread
22 convenience variable and in Python's InferiorThread.num attribute
23 are no longer unique between inferiors.
25 GDB now maintains a second thread ID per thread, referred to as the
26 global thread ID, which is the new equivalent of thread numbers in
27 previous releases. See also $_gthread below.
29 For backwards compatibility, MI's thread IDs always refer to global
32 * Commands that accept thread IDs now accept the qualified
33 INF_NUM.THR_NUM form as well. For example:
36 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
39 * In commands that accept a list of thread IDs, you can now refer to
40 all threads of an inferior using a star wildcard. GDB accepts
41 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
42 refer to all threads of the current inferior. For example, "info
45 * You can use "info threads -gid" to display the global thread ID of
48 * The new convenience variable $_gthread holds the global number of
51 * The new convenience variable $_inferior holds the number of the
54 * GDB now displays the ID and name of the thread that hit a breakpoint
55 or received a signal, if your program is multi-threaded. For
58 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
59 Thread 1 "main" received signal SIGINT, Interrupt.
61 * Record btrace now supports non-stop mode.
63 * Support for tracepoints on aarch64-linux was added in GDBserver.
65 * The 'record instruction-history' command now indicates speculative execution
66 when using the Intel Processor Trace recording format.
68 * GDB now allows users to specify explicit locations, bypassing
69 the linespec parser. This feature is also available to GDB/MI
72 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
73 GDB now is able to debug both AArch64 applications and ARM applications
76 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
77 including JIT compiling fast tracepoint's conditional expression bytecode
80 * GDB now supports displaced stepping on AArch64 GNU/Linux.
82 * "info threads", "info inferiors", "info display", "info checkpoints"
83 and "maint info program-spaces" now list the corresponding items in
84 ascending ID order, for consistency with all other "info" commands.
86 * In Ada, the overloads selection menu has been enhanced to display the
87 parameter types and the return types for the matching overloaded subprograms.
91 maint set target-non-stop (on|off|auto)
92 maint show target-non-stop
93 Control whether GDB targets always operate in non-stop mode even if
94 "set non-stop" is "off". The default is "auto", meaning non-stop
95 mode is enabled if supported by the target.
98 maint show bfd-sharing
99 Control the reuse of bfd objects.
103 Control display of debugging info regarding bfd caching.
107 Control display of debugging info regarding FreeBSD threads.
109 set remote multiprocess-extensions-packet
110 show remote multiprocess-extensions-packet
111 Set/show the use of the remote protocol multiprocess extensions.
113 set remote thread-events
114 show remote thread-events
115 Set/show the use of thread create/exit events.
117 set ada print-signatures on|off
118 show ada print-signatures"
119 Control whether parameter types and return types are displayed in overloads
120 selection menus. It is activaled (@code{on}) by default.
124 Controls the maximum size of memory, in bytes, that GDB will
125 allocate for value contents. Prevents incorrect programs from
126 causing GDB to allocate overly large buffers. Default is 64k.
128 * The "disassemble" command accepts a new modifier: /s.
129 It prints mixed source+disassembly like /m with two differences:
130 - disassembled instructions are now printed in program order, and
131 - and source for all relevant files is now printed.
132 The "/m" option is now considered deprecated: its "source-centric"
133 output hasn't proved useful in practice.
135 * The "record instruction-history" command accepts a new modifier: /s.
136 It behaves exactly like /m and prints mixed source+disassembly.
138 * The "set scheduler-locking" command supports a new mode "replay".
139 It behaves like "off" in record mode and like "on" in replay mode.
141 * Support for various ROM monitors has been removed:
143 target dbug dBUG ROM monitor for Motorola ColdFire
144 target picobug Motorola picobug monitor
145 target dink32 DINK32 ROM monitor for PowerPC
146 target m32r Renesas M32R/D ROM monitor
147 target mon2000 mon2000 ROM monitor
148 target ppcbug PPCBUG ROM monitor for PowerPC
150 * Support for reading/writing memory and extracting values on architectures
151 whose memory is addressable in units of any integral multiple of 8 bits.
156 Indicates that an exec system call was executed.
158 exec-events feature in qSupported
159 The qSupported packet allows GDB to request support for exec
160 events using the new 'gdbfeature' exec-event, and the qSupported
161 response can contain the corresponding 'stubfeature'. Set and
162 show commands can be used to display whether these features are enabled.
165 Equivalent to interrupting with the ^C character, but works in
168 thread created stop reason (T05 create:...)
169 Indicates that the thread was just created and is stopped at entry.
171 thread exit stop reply (w exitcode;tid)
172 Indicates that the thread has terminated.
175 Enables/disables thread create and exit event reporting. For
176 example, this is used in non-stop mode when GDB stops a set of
177 threads and synchronously waits for the their corresponding stop
178 replies. Without exit events, if one of the threads exits, GDB
179 would hang forever not knowing that it should no longer expect a
180 stop for that same thread.
184 Indicates that there are no resumed threads left in the target (all
185 threads are stopped). The remote stub reports support for this stop
186 reply to GDB's qSupported query.
188 QCatchSyscalls:1 [;SYSNO]...
190 Enable ("QCatchSyscalls:1") or disable ("QCatchSyscalls:0")
191 catching syscalls from the inferior process.
193 syscall_entry stop reason
194 Indicates that a syscall was just called.
196 syscall_return stop reason
197 Indicates that a syscall just returned.
199 QCatchSyscalls:1 in qSupported
200 The qSupported packet may now include QCatchSyscalls:1 in the reply
201 to indicate support for catching syscalls.
203 * Extended-remote exec events
205 ** GDB now has support for exec events on extended-remote Linux targets.
206 For such targets with Linux kernels 2.5.46 and later, this enables
207 follow-exec-mode and exec catchpoints.
209 set remote exec-event-feature-packet
210 show remote exec-event-feature-packet
211 Set/show the use of the remote exec event feature.
213 * Thread names in remote protocol
215 The reply to qXfer:threads:read may now include a name attribute for each
218 * Target remote mode fork and exec events
220 ** GDB now has support for fork and exec events on target remote mode
221 Linux targets. For such targets with Linux kernels 2.5.46 and later,
222 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
223 fork and exec catchpoints.
225 * Remote syscall events
227 ** GDB now has support for catch syscall on remote Linux targets,
228 currently enabled on x86/x86_64 architectures.
230 set remote catch-syscall-packet
231 show remote catch-syscall-packet
232 Set/show the use of the remote catch syscall feature.
236 ** The -var-set-format command now accepts the zero-hexadecimal
237 format. It outputs data in hexadecimal format with zero-padding on the
242 ** gdb.InferiorThread objects have a new attribute "global_num",
243 which refers to the thread's global thread ID. The existing
244 "num" attribute now refers to the thread's per-inferior number.
245 See "Per-inferior thread numbers" above.
246 ** gdb.InferiorThread objects have a new attribute "inferior", which
247 is the Inferior object the thread belongs to.
249 *** Changes in GDB 7.10
251 * Support for process record-replay and reverse debugging on aarch64*-linux*
252 targets has been added. GDB now supports recording of A64 instruction set
253 including advance SIMD instructions.
255 * Support for Sun's version of the "stabs" debug file format has been removed.
257 * GDB now honors the content of the file /proc/PID/coredump_filter
258 (PID is the process ID) on GNU/Linux systems. This file can be used
259 to specify the types of memory mappings that will be included in a
260 corefile. For more information, please refer to the manual page of
261 "core(5)". GDB also has a new command: "set use-coredump-filter
262 on|off". It allows to set whether GDB will read the content of the
263 /proc/PID/coredump_filter file when generating a corefile.
265 * The "info os" command on GNU/Linux can now display information on
267 "info os cpus" Listing of all cpus/cores on the system
269 * GDB has two new commands: "set serial parity odd|even|none" and
270 "show serial parity". These allows to set or show parity for the
273 * The "info source" command now displays the producer string if it was
274 present in the debug info. This typically includes the compiler version
275 and may include things like its command line arguments.
277 * The "info dll", an alias of the "info sharedlibrary" command,
278 is now available on all platforms.
280 * Directory names supplied to the "set sysroot" commands may be
281 prefixed with "target:" to tell GDB to access shared libraries from
282 the target system, be it local or remote. This replaces the prefix
283 "remote:". The default sysroot has been changed from "" to
284 "target:". "remote:" is automatically converted to "target:" for
285 backward compatibility.
287 * The system root specified by "set sysroot" will be prepended to the
288 filename of the main executable (if reported to GDB as absolute by
289 the operating system) when starting processes remotely, and when
290 attaching to already-running local or remote processes.
292 * GDB now supports automatic location and retrieval of executable
293 files from remote targets. Remote debugging can now be initiated
294 using only a "target remote" or "target extended-remote" command
295 (no "set sysroot" or "file" commands are required). See "New remote
298 * The "dump" command now supports verilog hex format.
300 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
302 * On GNU/Linux, GDB and gdbserver are now able to access executable
303 and shared library files without a "set sysroot" command when
304 attaching to processes running in different mount namespaces from
305 the debugger. This makes it possible to attach to processes in
306 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
307 See "New remote packets" below.
309 * The "tui reg" command now provides completion for all of the
310 available register groups, including target specific groups.
312 * The HISTSIZE environment variable is no longer read when determining
313 the size of GDB's command history. GDB now instead reads the dedicated
314 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
315 disables truncation of command history. Non-numeric values of GDBHISTSIZE
320 ** Memory ports can now be unbuffered.
324 ** gdb.Objfile objects have a new attribute "username",
325 which is the name of the objfile as specified by the user,
326 without, for example, resolving symlinks.
327 ** You can now write frame unwinders in Python.
328 ** gdb.Type objects have a new method "optimized_out",
329 returning optimized out gdb.Value instance of this type.
330 ** gdb.Value objects have new methods "reference_value" and
331 "const_value" which return a reference to the value and a
332 "const" version of the value respectively.
336 maint print symbol-cache
337 Print the contents of the symbol cache.
339 maint print symbol-cache-statistics
340 Print statistics of symbol cache usage.
342 maint flush-symbol-cache
343 Flush the contents of the symbol cache.
347 Start branch trace recording using Branch Trace Store (BTS) format.
350 Evaluate expression by using the compiler and print result.
354 Explicit commands for enabling and disabling tui mode.
357 set mpx bound on i386 and amd64
358 Support for bound table investigation on Intel MPX enabled applications.
362 Start branch trace recording using Intel Processor Trace format.
365 Print information about branch tracing internals.
367 maint btrace packet-history
368 Print the raw branch tracing data.
370 maint btrace clear-packet-history
371 Discard the stored raw branch tracing data.
374 Discard all branch tracing data. It will be fetched and processed
375 anew by the next "record" command.
380 Renamed from "set debug dwarf2-die".
382 Renamed from "show debug dwarf2-die".
385 Renamed from "set debug dwarf2-read".
386 show debug dwarf-read
387 Renamed from "show debug dwarf2-read".
389 maint set dwarf always-disassemble
390 Renamed from "maint set dwarf2 always-disassemble".
391 maint show dwarf always-disassemble
392 Renamed from "maint show dwarf2 always-disassemble".
394 maint set dwarf max-cache-age
395 Renamed from "maint set dwarf2 max-cache-age".
396 maint show dwarf max-cache-age
397 Renamed from "maint show dwarf2 max-cache-age".
400 show debug dwarf-line
401 Control display of debugging info regarding DWARF line processing.
405 Set the maximum number of candidates to be considered during
406 completion. The default value is 200. This limit allows GDB
407 to avoid generating large completion lists, the computation of
408 which can cause the debugger to become temporarily unresponsive.
410 set history remove-duplicates
411 show history remove-duplicates
412 Control the removal of duplicate history entries.
414 maint set symbol-cache-size
415 maint show symbol-cache-size
416 Control the size of the symbol cache.
418 set|show record btrace bts buffer-size
419 Set and show the size of the ring buffer used for branch tracing in
421 The obtained size may differ from the requested size. Use "info
422 record" to see the obtained buffer size.
424 set debug linux-namespaces
425 show debug linux-namespaces
426 Control display of debugging info regarding Linux namespaces.
428 set|show record btrace pt buffer-size
429 Set and show the size of the ring buffer used for branch tracing in
430 Intel Processor Trace format.
431 The obtained size may differ from the requested size. Use "info
432 record" to see the obtained buffer size.
434 maint set|show btrace pt skip-pad
435 Set and show whether PAD packets are skipped when computing the
438 * The command 'thread apply all' can now support new option '-ascending'
439 to call its specified command for all threads in ascending order.
441 * Python/Guile scripting
443 ** GDB now supports auto-loading of Python/Guile scripts contained in the
444 special section named `.debug_gdb_scripts'.
448 qXfer:btrace-conf:read
449 Return the branch trace configuration for the current thread.
451 Qbtrace-conf:bts:size
452 Set the requested ring buffer size for branch tracing in BTS format.
455 Enable Intel Procesor Trace-based branch tracing for the current
456 process. The remote stub reports support for this packet to GDB's
460 Set the requested ring buffer size for branch tracing in Intel Processor
464 Indicates a memory breakpoint instruction was executed, irrespective
465 of whether it was GDB that planted the breakpoint or the breakpoint
466 is hardcoded in the program. This is required for correct non-stop
470 Indicates the target stopped for a hardware breakpoint. This is
471 required for correct non-stop mode operation.
474 Return information about files on the remote system.
477 Return the full absolute name of the file that was executed to
478 create a process running on the remote system.
481 Select the filesystem on which vFile: operations with filename
482 arguments will operate. This is required for GDB to be able to
483 access files on remote targets where the remote stub does not
484 share a common filesystem with the inferior(s).
487 Indicates that a fork system call was executed.
490 Indicates that a vfork system call was executed.
492 vforkdone stop reason
493 Indicates that a vfork child of the specified process has executed
494 an exec or exit, allowing the vfork parent to resume execution.
496 fork-events and vfork-events features in qSupported
497 The qSupported packet allows GDB to request support for fork and
498 vfork events using new 'gdbfeatures' fork-events and vfork-events,
499 and the qSupported response can contain the corresponding
500 'stubfeatures'. Set and show commands can be used to display
501 whether these features are enabled.
503 * Extended-remote fork events
505 ** GDB now has support for fork events on extended-remote Linux
506 targets. For targets with Linux kernels 2.5.60 and later, this
507 enables follow-fork-mode and detach-on-fork for both fork and
508 vfork, as well as fork and vfork catchpoints.
510 * The info record command now shows the recording format and the
511 branch tracing configuration for the current thread when using
512 the btrace record target.
513 For the BTS format, it shows the ring buffer size.
515 * GDB now has support for DTrace USDT (Userland Static Defined
516 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
518 * GDB now supports access to vector registers on S/390 GNU/Linux
521 * Removed command line options
523 -xdb HP-UX XDB compatibility mode.
525 * Removed targets and native configurations
527 HP/PA running HP-UX hppa*-*-hpux*
528 Itanium running HP-UX ia64-*-hpux*
530 * New configure options
533 This configure option allows the user to build GDB with support for
534 Intel Processor Trace (default: auto). This requires libipt.
536 --with-libipt-prefix=PATH
537 Specify the path to the version of libipt that GDB should use.
538 $PATH/include should contain the intel-pt.h header and
539 $PATH/lib should contain the libipt.so library.
541 *** Changes in GDB 7.9.1
545 ** Xmethods can now specify a result type.
547 *** Changes in GDB 7.9
549 * GDB now supports hardware watchpoints on x86 GNU Hurd.
553 ** You can now access frame registers from Python scripts.
554 ** New attribute 'producer' for gdb.Symtab objects.
555 ** gdb.Objfile objects have a new attribute "progspace",
556 which is the gdb.Progspace object of the containing program space.
557 ** gdb.Objfile objects have a new attribute "owner".
558 ** gdb.Objfile objects have a new attribute "build_id",
559 which is the build ID generated when the file was built.
560 ** gdb.Objfile objects have a new method "add_separate_debug_file".
561 ** A new event "gdb.clear_objfiles" has been added, triggered when
562 selecting a new file to debug.
563 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
564 ** New function gdb.lookup_objfile.
566 New events which are triggered when GDB modifies the state of the
569 ** gdb.events.inferior_call_pre: Function call is about to be made.
570 ** gdb.events.inferior_call_post: Function call has just been made.
571 ** gdb.events.memory_changed: A memory location has been altered.
572 ** gdb.events.register_changed: A register has been altered.
574 * New Python-based convenience functions:
576 ** $_caller_is(name [, number_of_frames])
577 ** $_caller_matches(regexp [, number_of_frames])
578 ** $_any_caller_is(name [, number_of_frames])
579 ** $_any_caller_matches(regexp [, number_of_frames])
581 * GDB now supports the compilation and injection of source code into
582 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
583 to compile the source code to object code, and if successful, inject
584 and execute that code within the current context of the inferior.
585 Currently the C language is supported. The commands used to
586 interface with this new feature are:
588 compile code [-raw|-r] [--] [source code]
589 compile file [-raw|-r] filename
593 demangle [-l language] [--] name
594 Demangle "name" in the specified language, or the current language
595 if elided. This command is renamed from the "maint demangle" command.
596 The latter is kept as a no-op to avoid "maint demangle" being interpreted
597 as "maint demangler-warning".
599 queue-signal signal-name-or-number
600 Queue a signal to be delivered to the thread when it is resumed.
602 add-auto-load-scripts-directory directory
603 Add entries to the list of directories from which to load auto-loaded
606 maint print user-registers
607 List all currently available "user" registers.
609 compile code [-r|-raw] [--] [source code]
610 Compile, inject, and execute in the inferior the executable object
611 code produced by compiling the provided source code.
613 compile file [-r|-raw] filename
614 Compile and inject into the inferior the executable object code
615 produced by compiling the source code stored in the filename
618 * On resume, GDB now always passes the signal the program had stopped
619 for to the thread the signal was sent to, even if the user changed
620 threads before resuming. Previously GDB would often (but not
621 always) deliver the signal to the thread that happens to be current
624 * Conversely, the "signal" command now consistently delivers the
625 requested signal to the current thread. GDB now asks for
626 confirmation if the program had stopped for a signal and the user
627 switched threads meanwhile.
629 * "breakpoint always-inserted" modes "off" and "auto" merged.
631 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
632 won't remove breakpoints from the target until all threads stop,
633 even in non-stop mode. The "auto" mode has been removed, and "off"
634 is now the default mode.
638 set debug symbol-lookup
639 show debug symbol-lookup
640 Control display of debugging info regarding symbol lookup.
644 ** The -list-thread-groups command outputs an exit-code field for
645 inferiors that have exited.
649 MIPS SDE mips*-sde*-elf*
653 Support for these obsolete configurations has been removed.
655 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
656 SGI Irix-5.x mips-*-irix5*
657 SGI Irix-6.x mips-*-irix6*
658 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
659 VAX running Ultrix vax-*-ultrix*
661 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
662 and "assf"), have been removed. Use the "sharedlibrary" command, or
663 its alias "share", instead.
665 *** Changes in GDB 7.8
667 * New command line options
670 This is an alias for the --data-directory option.
672 * GDB supports printing and modifying of variable length automatic arrays
673 as specified in ISO C99.
675 * The ARM simulator now supports instruction level tracing
676 with or without disassembly.
680 GDB now has support for scripting using Guile. Whether this is
681 available is determined at configure time.
682 Guile version 2.0 or greater is required.
683 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
685 * New commands (for set/show, see "New options" below)
689 Invoke CODE by passing it to the Guile interpreter.
693 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
695 info auto-load guile-scripts [regexp]
696 Print the list of automatically loaded Guile scripts.
698 * The source command is now capable of sourcing Guile scripts.
699 This feature is dependent on the debugger being built with Guile support.
703 set print symbol-loading (off|brief|full)
704 show print symbol-loading
705 Control whether to print informational messages when loading symbol
706 information for a file. The default is "full", but when debugging
707 programs with large numbers of shared libraries the amount of output
710 set guile print-stack (none|message|full)
711 show guile print-stack
712 Show a stack trace when an error is encountered in a Guile script.
714 set auto-load guile-scripts (on|off)
715 show auto-load guile-scripts
716 Control auto-loading of Guile script files.
718 maint ada set ignore-descriptive-types (on|off)
719 maint ada show ignore-descriptive-types
720 Control whether the debugger should ignore descriptive types in Ada
721 programs. The default is not to ignore the descriptive types. See
722 the user manual for more details on descriptive types and the intended
723 usage of this option.
725 set auto-connect-native-target
727 Control whether GDB is allowed to automatically connect to the
728 native target for the run, attach, etc. commands when not connected
729 to any target yet. See also "target native" below.
731 set record btrace replay-memory-access (read-only|read-write)
732 show record btrace replay-memory-access
733 Control what memory accesses are allowed during replay.
735 maint set target-async (on|off)
736 maint show target-async
737 This controls whether GDB targets operate in synchronous or
738 asynchronous mode. Normally the default is asynchronous, if it is
739 available; but this can be changed to more easily debug problems
740 occurring only in synchronous mode.
742 set mi-async (on|off)
744 Control whether MI asynchronous mode is preferred. This supersedes
745 "set target-async" of previous GDB versions.
747 * "set target-async" is deprecated as a CLI option and is now an alias
748 for "set mi-async" (only puts MI into async mode).
750 * Background execution commands (e.g., "c&", "s&", etc.) are now
751 possible ``out of the box'' if the target supports them. Previously
752 the user would need to explicitly enable the possibility with the
753 "set target-async on" command.
755 * New features in the GDB remote stub, GDBserver
757 ** New option --debug-format=option1[,option2,...] allows one to add
758 additional text to each output. At present only timestamps
759 are supported: --debug-format=timestamps.
760 Timestamps can also be turned on with the
761 "monitor set debug-format timestamps" command from GDB.
763 * The 'record instruction-history' command now starts counting instructions
764 at one. This also affects the instruction ranges reported by the
765 'record function-call-history' command when given the /i modifier.
767 * The command 'record function-call-history' supports a new modifier '/c' to
768 indent the function names based on their call stack depth.
769 The fields for the '/i' and '/l' modifier have been reordered.
770 The source line range is now prefixed with 'at'.
771 The instruction range is now prefixed with 'inst'.
772 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
773 "record instruction-history" and "list" commands.
775 * The ranges given as arguments to the 'record function-call-history' and
776 'record instruction-history' commands are now inclusive.
778 * The btrace record target now supports the 'record goto' command.
779 For locations inside the execution trace, the back trace is computed
780 based on the information stored in the execution trace.
782 * The btrace record target supports limited reverse execution and replay.
783 The target does not record data and therefore does not allow reading
786 * The "catch syscall" command now works on s390*-linux* targets.
788 * The "compare-sections" command is no longer specific to target
789 remote. It now works with all targets.
791 * All native targets are now consistently called "native".
792 Consequently, the "target child", "target GNU", "target djgpp",
793 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
794 commands have been replaced with "target native". The QNX/NTO port
795 leaves the "procfs" target in place and adds a "native" target for
796 consistency with other ports. The impact on users should be minimal
797 as these commands previously either throwed an error, or were
798 no-ops. The target's name is visible in the output of the following
799 commands: "help target", "info target", "info files", "maint print
802 * The "target native" command now connects to the native target. This
803 can be used to launch native programs even when "set
804 auto-connect-native-target" is set to off.
806 * GDB now supports access to Intel MPX registers on GNU/Linux.
808 * Support for Intel AVX-512 registers on GNU/Linux.
809 Support displaying and modifying Intel AVX-512 registers
810 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
814 qXfer:btrace:read's annex
815 The qXfer:btrace:read packet supports a new annex 'delta' to read
816 branch trace incrementally.
820 ** Valid Python operations on gdb.Value objects representing
821 structs/classes invoke the corresponding overloaded operators if
823 ** New `Xmethods' feature in the Python API. Xmethods are
824 additional methods or replacements for existing methods of a C++
825 class. This feature is useful for those cases where a method
826 defined in C++ source code could be inlined or optimized out by
827 the compiler, making it unavailable to GDB.
830 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
832 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
833 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
834 its alias "share", instead.
836 * The commands "set remotebaud" and "show remotebaud" are no longer
837 supported. Use "set serial baud" and "show serial baud" (respectively)
842 ** A new option "-gdb-set mi-async" replaces "-gdb-set
843 target-async". The latter is left as a deprecated alias of the
844 former for backward compatibility. If the target supports it,
845 CLI background execution commands are now always possible by
846 default, independently of whether the frontend stated a
847 preference for asynchronous execution with "-gdb-set mi-async".
848 Previously "-gdb-set target-async off" affected both MI execution
849 commands and CLI execution commands.
851 *** Changes in GDB 7.7
853 * Improved support for process record-replay and reverse debugging on
854 arm*-linux* targets. Support for thumb32 and syscall instruction
855 recording has been added.
857 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
859 * GDB now supports Fission DWP file format version 2.
860 http://gcc.gnu.org/wiki/DebugFission
862 * New convenience function "$_isvoid", to check whether an expression
863 is void. A void expression is an expression where the type of the
864 result is "void". For example, some convenience variables may be
865 "void" when evaluated (e.g., "$_exitcode" before the execution of
866 the program being debugged; or an undefined convenience variable).
867 Another example, when calling a function whose return type is
870 * The "maintenance print objfiles" command now takes an optional regexp.
872 * The "catch syscall" command now works on arm*-linux* targets.
874 * GDB now consistently shows "<not saved>" when printing values of
875 registers the debug info indicates have not been saved in the frame
876 and there's nowhere to retrieve them from
877 (callee-saved/call-clobbered registers):
882 (gdb) info registers rax
885 Before, the former would print "<optimized out>", and the latter
886 "*value not available*".
888 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
893 ** Frame filters and frame decorators have been added.
894 ** Temporary breakpoints are now supported.
895 ** Line tables representation has been added.
896 ** New attribute 'parent_type' for gdb.Field objects.
897 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
898 ** New attribute 'name' for gdb.Type objects.
902 Nios II ELF nios2*-*-elf
903 Nios II GNU/Linux nios2*-*-linux
904 Texas Instruments MSP430 msp430*-*-elf
906 * Removed native configurations
908 Support for these a.out NetBSD and OpenBSD obsolete configurations has
909 been removed. ELF variants of these configurations are kept supported.
911 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
912 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
913 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
914 i[34567]86-*-openbsd3.[0-3]
915 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
916 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
917 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
921 Like "catch throw", but catches a re-thrown exception.
923 Renamed from old "maint check-symtabs".
925 Perform consistency checks on symtabs.
927 Expand symtabs matching an optional regexp.
930 Display the details of GDB configure-time options.
932 maint set|show per-command
933 maint set|show per-command space
934 maint set|show per-command time
935 maint set|show per-command symtab
936 Enable display of per-command gdb resource usage.
938 remove-symbol-file FILENAME
939 remove-symbol-file -a ADDRESS
940 Remove a symbol file added via add-symbol-file. The file to remove
941 can be identified by its filename or by an address that lies within
942 the boundaries of this symbol file in memory.
945 info exceptions REGEXP
946 Display the list of Ada exceptions defined in the program being
947 debugged. If provided, only the exceptions whose names match REGEXP
952 set debug symfile off|on
954 Control display of debugging info regarding reading symbol files and
955 symbol tables within those files
957 set print raw frame-arguments
958 show print raw frame-arguments
959 Set/show whether to print frame arguments in raw mode,
960 disregarding any defined pretty-printers.
962 set remote trace-status-packet
963 show remote trace-status-packet
964 Set/show the use of remote protocol qTStatus packet.
968 Control display of debugging messages related to Nios II targets.
972 Control whether target-assisted range stepping is enabled.
974 set startup-with-shell
975 show startup-with-shell
976 Specifies whether Unix child processes are started via a shell or
981 Use the target memory cache for accesses to the code segment. This
982 improves performance of remote debugging (particularly disassembly).
984 * You can now use a literal value 'unlimited' for options that
985 interpret 0 or -1 as meaning "unlimited". E.g., "set
986 trace-buffer-size unlimited" is now an alias for "set
987 trace-buffer-size -1" and "set height unlimited" is now an alias for
990 * The "set debug symtab-create" debugging option of GDB has been changed to
991 accept a verbosity level. 0 means "off", 1 provides basic debugging
992 output, and values of 2 or greater provides more verbose output.
994 * New command-line options
996 Display the details of GDB configure-time options.
998 * The command 'tsave' can now support new option '-ctf' to save trace
999 buffer in Common Trace Format.
1001 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1004 * GDB now implements the the C++ 'typeid' operator.
1006 * The new convenience variable $_exception holds the exception being
1007 thrown or caught at an exception-related catchpoint.
1009 * The exception-related catchpoints, like "catch throw", now accept a
1010 regular expression which can be used to filter exceptions by type.
1012 * The new convenience variable $_exitsignal is automatically set to
1013 the terminating signal number when the program being debugged dies
1014 due to an uncaught signal.
1018 ** All MI commands now accept an optional "--language" option.
1019 Support for this feature can be verified by using the "-list-features"
1020 command, which should contain "language-option".
1022 ** The new command -info-gdb-mi-command allows the user to determine
1023 whether a GDB/MI command is supported or not.
1025 ** The "^error" result record returned when trying to execute an undefined
1026 GDB/MI command now provides a variable named "code" whose content is the
1027 "undefined-command" error code. Support for this feature can be verified
1028 by using the "-list-features" command, which should contain
1029 "undefined-command-error-code".
1031 ** The -trace-save MI command can optionally save trace buffer in Common
1034 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1036 ** The command -data-list-register-values now accepts an optional
1037 "--skip-unavailable" option. When used, only the available registers
1040 ** The new command -trace-frame-collected dumps collected variables,
1041 computed expressions, tvars, memory and registers in a traceframe.
1043 ** The commands -stack-list-locals, -stack-list-arguments and
1044 -stack-list-variables now accept an option "--skip-unavailable".
1045 When used, only the available locals or arguments are displayed.
1047 ** The -exec-run command now accepts an optional "--start" option.
1048 When used, the command follows the same semantics as the "start"
1049 command, stopping the program's execution at the start of its
1050 main subprogram. Support for this feature can be verified using
1051 the "-list-features" command, which should contain
1052 "exec-run-start-option".
1054 ** The new commands -catch-assert and -catch-exceptions insert
1055 catchpoints stopping the program when Ada exceptions are raised.
1057 ** The new command -info-ada-exceptions provides the equivalent of
1058 the new "info exceptions" command.
1060 * New system-wide configuration scripts
1061 A GDB installation now provides scripts suitable for use as system-wide
1062 configuration scripts for the following systems:
1066 * GDB now supports target-assigned range stepping with remote targets.
1067 This improves the performance of stepping source lines by reducing
1068 the number of control packets from/to GDB. See "New remote packets"
1071 * GDB now understands the element 'tvar' in the XML traceframe info.
1072 It has the id of the collected trace state variables.
1074 * On S/390 targets that provide the transactional-execution feature,
1075 the program interruption transaction diagnostic block (TDB) is now
1076 represented as a number of additional "registers" in GDB.
1078 * New remote packets
1082 The vCont packet supports a new 'r' action, that tells the remote
1083 stub to step through an address range itself, without GDB
1084 involvemement at each single-step.
1086 qXfer:libraries-svr4:read's annex
1087 The previously unused annex of the qXfer:libraries-svr4:read packet
1088 is now used to support passing an argument list. The remote stub
1089 reports support for this argument list to GDB's qSupported query.
1090 The defined arguments are "start" and "prev", used to reduce work
1091 necessary for library list updating, resulting in significant
1094 * New features in the GDB remote stub, GDBserver
1096 ** GDBserver now supports target-assisted range stepping. Currently
1097 enabled on x86/x86_64 GNU/Linux targets.
1099 ** GDBserver now adds element 'tvar' in the XML in the reply to
1100 'qXfer:traceframe-info:read'. It has the id of the collected
1101 trace state variables.
1103 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1106 * New 'z' formatter for printing and examining memory, this displays the
1107 value as hexadecimal zero padded on the left to the size of the type.
1109 * GDB can now use Windows x64 unwinding data.
1111 * The "set remotebaud" command has been replaced by "set serial baud".
1112 Similarly, "show remotebaud" has been replaced by "show serial baud".
1113 The "set remotebaud" and "show remotebaud" commands are still available
1114 to provide backward compatibility with older versions of GDB.
1116 *** Changes in GDB 7.6
1118 * Target record has been renamed to record-full.
1119 Record/replay is now enabled with the "record full" command.
1120 This also affects settings that are associated with full record/replay
1121 that have been moved from "set/show record" to "set/show record full":
1123 set|show record full insn-number-max
1124 set|show record full stop-at-limit
1125 set|show record full memory-query
1127 * A new record target "record-btrace" has been added. The new target
1128 uses hardware support to record the control-flow of a process. It
1129 does not support replaying the execution, but it implements the
1130 below new commands for investigating the recorded execution log.
1131 This new recording method can be enabled using:
1135 The "record-btrace" target is only available on Intel Atom processors
1136 and requires a Linux kernel 2.6.32 or later.
1138 * Two new commands have been added for record/replay to give information
1139 about the recorded execution without having to replay the execution.
1140 The commands are only supported by "record btrace".
1142 record instruction-history prints the execution history at
1143 instruction granularity
1145 record function-call-history prints the execution history at
1146 function granularity
1148 * New native configurations
1150 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1151 FreeBSD/powerpc powerpc*-*-freebsd
1152 x86_64/Cygwin x86_64-*-cygwin*
1153 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1157 ARM AArch64 aarch64*-*-elf
1158 ARM AArch64 GNU/Linux aarch64*-*-linux
1159 Lynx 178 PowerPC powerpc-*-lynx*178
1160 x86_64/Cygwin x86_64-*-cygwin*
1161 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1163 * If the configured location of system.gdbinit file (as given by the
1164 --with-system-gdbinit option at configure time) is in the
1165 data-directory (as specified by --with-gdb-datadir at configure
1166 time) or in one of its subdirectories, then GDB will look for the
1167 system-wide init file in the directory specified by the
1168 --data-directory command-line option.
1170 * New command line options:
1172 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1173 other initialization files, unlike -nx which disables all of them.
1175 * Removed command line options
1177 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1180 * The 'ptype' and 'whatis' commands now accept an argument to control
1183 * 'info proc' now works on some core files.
1187 ** Vectors can be created with gdb.Type.vector.
1189 ** Python's atexit.register now works in GDB.
1191 ** Types can be pretty-printed via a Python API.
1193 ** Python 3 is now supported (in addition to Python 2.4 or later)
1195 ** New class gdb.Architecture exposes GDB's internal representation
1196 of architecture in the Python API.
1198 ** New method Frame.architecture returns the gdb.Architecture object
1199 corresponding to the frame's architecture.
1201 * New Python-based convenience functions:
1203 ** $_memeq(buf1, buf2, length)
1204 ** $_streq(str1, str2)
1206 ** $_regex(str, regex)
1208 * The 'cd' command now defaults to using '~' (the home directory) if not
1211 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1212 default for GCC since November 2000.
1214 * The command 'forward-search' can now be abbreviated as 'fo'.
1216 * The command 'info tracepoints' can now display 'installed on target'
1217 or 'not installed on target' for each non-pending location of tracepoint.
1219 * New configure options
1221 --enable-libmcheck/--disable-libmcheck
1222 By default, development versions are built with -lmcheck on hosts
1223 that support it, in order to help track memory corruption issues.
1224 Release versions, on the other hand, are built without -lmcheck
1225 by default. The --enable-libmcheck/--disable-libmcheck configure
1226 options allow the user to override that default.
1227 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1228 This configure option allows the user to build GDB with
1229 libbabeltrace using which GDB can read Common Trace Format data.
1231 * New commands (for set/show, see "New options" below)
1234 Catch signals. This is similar to "handle", but allows commands and
1235 conditions to be attached.
1238 List the BFDs known to GDB.
1240 python-interactive [command]
1242 Start a Python interactive prompt, or evaluate the optional command
1243 and print the result of expressions.
1246 "py" is a new alias for "python".
1248 enable type-printer [name]...
1249 disable type-printer [name]...
1250 Enable or disable type printers.
1254 ** For the Renesas Super-H architecture, the "regs" command has been removed
1255 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1260 set print type methods (on|off)
1261 show print type methods
1262 Control whether method declarations are displayed by "ptype".
1263 The default is to show them.
1265 set print type typedefs (on|off)
1266 show print type typedefs
1267 Control whether typedef definitions are displayed by "ptype".
1268 The default is to show them.
1270 set filename-display basename|relative|absolute
1271 show filename-display
1272 Control the way in which filenames is displayed.
1273 The default is "relative", which preserves previous behavior.
1275 set trace-buffer-size
1276 show trace-buffer-size
1277 Request target to change the size of trace buffer.
1279 set remote trace-buffer-size-packet auto|on|off
1280 show remote trace-buffer-size-packet
1281 Control the use of the remote protocol `QTBuffer:size' packet.
1285 Control display of debugging messages related to ARM AArch64.
1288 set debug coff-pe-read
1289 show debug coff-pe-read
1290 Control display of debugging messages related to reading of COFF/PE
1295 Control display of debugging messages related to Mach-O symbols
1298 set debug notification
1299 show debug notification
1300 Control display of debugging info for async remote notification.
1304 ** Command parameter changes are now notified using new async record
1305 "=cmd-param-changed".
1306 ** Trace frame changes caused by command "tfind" are now notified using
1307 new async record "=traceframe-changed".
1308 ** The creation, deletion and modification of trace state variables
1309 are now notified using new async records "=tsv-created",
1310 "=tsv-deleted" and "=tsv-modified".
1311 ** The start and stop of process record are now notified using new
1312 async record "=record-started" and "=record-stopped".
1313 ** Memory changes are now notified using new async record
1315 ** The data-disassemble command response will include a "fullname" field
1316 containing the absolute file name when source has been requested.
1317 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1318 command, to allow pattern filling of memory areas.
1319 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1320 library load/unload events.
1321 ** The response to breakpoint commands and breakpoint async records
1322 includes an "installed" field containing a boolean state about each
1323 non-pending tracepoint location is whether installed on target or not.
1324 ** Output of the "-trace-status" command includes a "trace-file" field
1325 containing the name of the trace file being examined. This field is
1326 optional, and only present when examining a trace file.
1327 ** The "fullname" field is now always present along with the "file" field,
1328 even if the file cannot be found by GDB.
1330 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1331 You must have the LZMA library available when configuring GDB for this
1332 feature to be enabled. For more information, see:
1333 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1335 * New remote packets
1338 Set the size of trace buffer. The remote stub reports support for this
1339 packet to gdb's qSupported query.
1342 Enable Branch Trace Store (BTS)-based branch tracing for the current
1343 thread. The remote stub reports support for this packet to gdb's
1347 Disable branch tracing for the current thread. The remote stub reports
1348 support for this packet to gdb's qSupported query.
1351 Read the traced branches for the current thread. The remote stub
1352 reports support for this packet to gdb's qSupported query.
1354 *** Changes in GDB 7.5
1356 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1357 for more x32 ABI info.
1359 * GDB now supports access to MIPS DSP registers on Linux targets.
1361 * GDB now supports debugging microMIPS binaries.
1363 * The "info os" command on GNU/Linux can now display information on
1364 several new classes of objects managed by the operating system:
1365 "info os procgroups" lists process groups
1366 "info os files" lists file descriptors
1367 "info os sockets" lists internet-domain sockets
1368 "info os shm" lists shared-memory regions
1369 "info os semaphores" lists semaphores
1370 "info os msg" lists message queues
1371 "info os modules" lists loaded kernel modules
1373 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1374 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1375 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1376 options and inspect the probe arguments using the new $_probe_arg family
1377 of convenience variables. You can obtain more information about SystemTap
1378 in <http://sourceware.org/systemtap/>.
1380 * GDB now supports reversible debugging on ARM, it allows you to
1381 debug basic ARM and THUMB instructions, and provides
1382 record/replay support.
1384 * The option "symbol-reloading" has been deleted as it is no longer used.
1388 ** GDB commands implemented in Python can now be put in command class
1391 ** The "maint set python print-stack on|off" is now deleted.
1393 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1394 apply "flag enum"-style pretty-printing to any enum.
1396 ** gdb.lookup_symbol can now work when there is no current frame.
1398 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1399 the source at which the symbol was defined.
1401 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1402 method 'value'. The former indicates whether the symbol needs a
1403 frame in order to compute its value, and the latter computes the
1406 ** A new method 'referenced_value' on gdb.Value objects which can
1407 dereference pointer as well as C++ reference values.
1409 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1410 which return the global and static blocks (as gdb.Block objects),
1411 of the underlying symbol table, respectively.
1413 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1414 object associated with a PC value.
1416 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1417 of the address range occupied by code for the current source line.
1419 * Go language support.
1420 GDB now supports debugging programs written in the Go programming
1423 * GDBserver now supports stdio connections.
1424 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1426 * The binary "gdbtui" can no longer be built or installed.
1427 Use "gdb -tui" instead.
1429 * GDB will now print "flag" enums specially. A flag enum is one where
1430 all the enumerator values have no bits in common when pairwise
1431 "and"ed. When printing a value whose type is a flag enum, GDB will
1432 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1433 (gdb) print (enum E) 3
1436 * The filename part of a linespec will now match trailing components
1437 of a source file name. For example, "break gcc/expr.c:1000" will
1438 now set a breakpoint in build/gcc/expr.c, but not
1439 build/libcpp/expr.c.
1441 * The "info proc" and "generate-core-file" commands will now also
1442 work on remote targets connected to GDBserver on Linux.
1444 * The command "info catch" has been removed. It has been disabled
1445 since December 2007.
1447 * The "catch exception" and "catch assert" commands now accept
1448 a condition at the end of the command, much like the "break"
1449 command does. For instance:
1451 (gdb) catch exception Constraint_Error if Barrier = True
1453 Previously, it was possible to add a condition to such catchpoints,
1454 but it had to be done as a second step, after the catchpoint had been
1455 created, using the "condition" command.
1457 * The "info static-tracepoint-marker" command will now also work on
1458 native Linux targets with in-process agent.
1460 * GDB can now set breakpoints on inlined functions.
1462 * The .gdb_index section has been updated to include symbols for
1463 inlined functions. GDB will ignore older .gdb_index sections by
1464 default, which could cause symbol files to be loaded more slowly
1465 until their .gdb_index sections can be recreated. The new command
1466 "set use-deprecated-index-sections on" will cause GDB to use any older
1467 .gdb_index sections it finds. This will restore performance, but the
1468 ability to set breakpoints on inlined functions will be lost in symbol
1469 files with older .gdb_index sections.
1471 The .gdb_index section has also been updated to record more information
1472 about each symbol. This speeds up the "info variables", "info functions"
1473 and "info types" commands when used with programs having the .gdb_index
1474 section, as well as speeding up debugging with shared libraries using
1475 the .gdb_index section.
1477 * Ada support for GDB/MI Variable Objects has been added.
1479 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1484 ** New command -info-os is the MI equivalent of "info os".
1486 ** Output logs ("set logging" and related) now include MI output.
1490 ** "set use-deprecated-index-sections on|off"
1491 "show use-deprecated-index-sections on|off"
1492 Controls the use of deprecated .gdb_index sections.
1494 ** "catch load" and "catch unload" can be used to stop when a shared
1495 library is loaded or unloaded, respectively.
1497 ** "enable count" can be used to auto-disable a breakpoint after
1500 ** "info vtbl" can be used to show the virtual method tables for
1501 C++ and Java objects.
1503 ** "explore" and its sub commands "explore value" and "explore type"
1504 can be used to recursively explore values and types of
1505 expressions. These commands are available only if GDB is
1506 configured with '--with-python'.
1508 ** "info auto-load" shows status of all kinds of auto-loaded files,
1509 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1510 sequences of commands files, "info auto-load python-scripts"
1511 shows status of auto-loading Python script files,
1512 "info auto-load local-gdbinit" shows status of loading init file
1513 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1514 status of inferior specific thread debugging shared library loading.
1516 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1517 and "show auto-load-scripts" commands have been deprecated, use their
1518 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1519 and "show auto-load python-scripts" counterparts instead.
1521 ** "dprintf location,format,args..." creates a dynamic printf, which
1522 is basically a breakpoint that does a printf and immediately
1523 resumes your program's execution, so it is like a printf that you
1524 can insert dynamically at runtime instead of at compiletime.
1526 ** "set print symbol"
1528 Controls whether GDB attempts to display the symbol, if any,
1529 corresponding to addresses it prints. This defaults to "on", but
1530 you can set it to "off" to restore GDB's previous behavior.
1532 * Deprecated commands
1534 ** For the Renesas Super-H architecture, the "regs" command has been
1535 deprecated, and "info all-registers" should be used instead.
1539 Renesas RL78 rl78-*-elf
1540 HP OpenVMS ia64 ia64-hp-openvms*
1542 * GDBserver supports evaluation of breakpoint conditions. When
1543 support is advertised by GDBserver, GDB may be told to send the
1544 breakpoint conditions in bytecode form to GDBserver. GDBserver
1545 will only report the breakpoint trigger to GDB when its condition
1550 set mips compression
1551 show mips compression
1552 Select the compressed ISA encoding used in functions that have no symbol
1553 information available. The encoding can be set to either of:
1556 and is updated automatically from ELF file flags if available.
1558 set breakpoint condition-evaluation
1559 show breakpoint condition-evaluation
1560 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1561 GDBserver ("target"). Default option "auto" chooses the most efficient
1563 This option can improve debugger efficiency depending on the speed of the
1567 Disable auto-loading globally.
1570 Show auto-loading setting of all kinds of auto-loaded files.
1572 set auto-load gdb-scripts on|off
1573 show auto-load gdb-scripts
1574 Control auto-loading of GDB canned sequences of commands files.
1576 set auto-load python-scripts on|off
1577 show auto-load python-scripts
1578 Control auto-loading of Python script files.
1580 set auto-load local-gdbinit on|off
1581 show auto-load local-gdbinit
1582 Control loading of init file (.gdbinit) from current directory.
1584 set auto-load libthread-db on|off
1585 show auto-load libthread-db
1586 Control auto-loading of inferior specific thread debugging shared library.
1588 set auto-load scripts-directory <dir1>[:<dir2>...]
1589 show auto-load scripts-directory
1590 Set a list of directories from which to load auto-loaded scripts.
1591 Automatically loaded Python scripts and GDB scripts are located in one
1592 of the directories listed by this option.
1593 The delimiter (':' above) may differ according to the host platform.
1595 set auto-load safe-path <dir1>[:<dir2>...]
1596 show auto-load safe-path
1597 Set a list of directories from which it is safe to auto-load files.
1598 The delimiter (':' above) may differ according to the host platform.
1600 set debug auto-load on|off
1601 show debug auto-load
1602 Control display of debugging info for auto-loading the files above.
1604 set dprintf-style gdb|call|agent
1606 Control the way in which a dynamic printf is performed; "gdb"
1607 requests a GDB printf command, while "call" causes dprintf to call a
1608 function in the inferior. "agent" requests that the target agent
1609 (such as GDBserver) do the printing.
1611 set dprintf-function <expr>
1612 show dprintf-function
1613 set dprintf-channel <expr>
1614 show dprintf-channel
1615 Set the function and optional first argument to the call when using
1616 the "call" style of dynamic printf.
1618 set disconnected-dprintf on|off
1619 show disconnected-dprintf
1620 Control whether agent-style dynamic printfs continue to be in effect
1621 after GDB disconnects.
1623 * New configure options
1625 --with-auto-load-dir
1626 Configure default value for the 'set auto-load scripts-directory'
1627 setting above. It defaults to '$debugdir:$datadir/auto-load',
1628 $debugdir representing global debugging info directories (available
1629 via 'show debug-file-directory') and $datadir representing GDB's data
1630 directory (available via 'show data-directory').
1632 --with-auto-load-safe-path
1633 Configure default value for the 'set auto-load safe-path' setting
1634 above. It defaults to the --with-auto-load-dir setting.
1636 --without-auto-load-safe-path
1637 Set 'set auto-load safe-path' to '/', effectively disabling this
1640 * New remote packets
1642 z0/z1 conditional breakpoints extension
1644 The z0/z1 breakpoint insertion packets have been extended to carry
1645 a list of conditional expressions over to the remote stub depending on the
1646 condition evaluation mode. The use of this extension can be controlled
1647 via the "set remote conditional-breakpoints-packet" command.
1651 Specify the signals which the remote stub may pass to the debugged
1652 program without GDB involvement.
1654 * New command line options
1656 --init-command=FILE, -ix Like --command, -x but execute it
1657 before loading inferior.
1658 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1659 execute it before loading inferior.
1661 *** Changes in GDB 7.4
1663 * GDB now handles ambiguous linespecs more consistently; the existing
1664 FILE:LINE support has been expanded to other types of linespecs. A
1665 breakpoint will now be set on all matching locations in all
1666 inferiors, and locations will be added or removed according to
1669 * GDB now allows you to skip uninteresting functions and files when
1670 stepping with the "skip function" and "skip file" commands.
1672 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1673 and "show remote hardware-watchpoint-length-limit". These allows to
1674 set or show the maximum length limit (in bytes) of a remote
1675 target hardware watchpoint.
1677 This allows e.g. to use "unlimited" hardware watchpoints with the
1678 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1679 watchpoints are slower than real hardware watchpoints but are
1680 significantly faster than gdb software watchpoints.
1684 ** The register_pretty_printer function in module gdb.printing now takes
1685 an optional `replace' argument. If True, the new printer replaces any
1688 ** The "maint set python print-stack on|off" command has been
1689 deprecated and will be deleted in GDB 7.5.
1690 A new command: "set python print-stack none|full|message" has
1691 replaced it. Additionally, the default for "print-stack" is
1692 now "message", which just prints the error message without
1695 ** A prompt substitution hook (prompt_hook) is now available to the
1698 ** A new Python module, gdb.prompt has been added to the GDB Python
1699 modules library. This module provides functionality for
1700 escape sequences in prompts (used by set/show
1701 extended-prompt). These escape sequences are replaced by their
1702 corresponding value.
1704 ** Python commands and convenience-functions located in
1705 'data-directory'/python/gdb/command and
1706 'data-directory'/python/gdb/function are now automatically loaded
1709 ** Blocks now provide four new attributes. global_block and
1710 static_block will return the global and static blocks
1711 respectively. is_static and is_global are boolean attributes
1712 that indicate if the block is one of those two types.
1714 ** Symbols now provide the "type" attribute, the type of the symbol.
1716 ** The "gdb.breakpoint" function has been deprecated in favor of
1719 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1720 of a function. This class is based on the "finish" command
1721 available in the CLI.
1723 ** Type objects for struct and union types now allow access to
1724 the fields using standard Python dictionary (mapping) methods.
1725 For example, "some_type['myfield']" now works, as does
1726 "some_type.items()".
1728 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1731 ** A new function, "deep_items" has been added to the gdb.types
1732 module in the GDB Python modules library. This function returns
1733 an iterator over the fields of a struct or union type. Unlike
1734 the standard Python "iteritems" method, it will recursively traverse
1735 any anonymous fields.
1739 ** "*stopped" events can report several new "reason"s, such as
1742 ** Breakpoint changes are now notified using new async records, like
1743 "=breakpoint-modified".
1745 ** New command -ada-task-info.
1747 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1748 $sdir specifies the default system locations of shared libraries.
1749 $pdir specifies the directory where the libpthread used by the application
1752 GDB no longer looks in $sdir and $pdir after it has searched the directories
1753 mentioned in libthread-db-search-path. If you want to search those
1754 directories, they must be specified in libthread-db-search-path.
1755 The default value of libthread-db-search-path on GNU/Linux and Solaris
1756 systems is now "$sdir:$pdir".
1758 $pdir is not supported by gdbserver, it is currently ignored.
1759 $sdir is supported by gdbserver.
1761 * New configure option --with-iconv-bin.
1762 When using the internationalization support like the one in the GNU C
1763 library, GDB will invoke the "iconv" program to get a list of supported
1764 character sets. If this program lives in a non-standard location, one can
1765 use this option to specify where to find it.
1767 * When natively debugging programs on PowerPC BookE processors running
1768 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1769 watchpoints, which specify a mask in addition to an address to watch.
1770 The mask specifies that some bits of an address (the bits which are
1771 reset in the mask) should be ignored when matching the address accessed
1772 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1773 section in the user manual for more details.
1775 * The new option --once causes GDBserver to stop listening for connections once
1776 the first connection is made. The listening port used by GDBserver will
1777 become available after that.
1779 * New commands "info macros" and "alias" have been added.
1781 * New function parameters suffix @entry specifies value of function parameter
1782 at the time the function got called. Entry values are available only since
1788 "!" is now an alias of the "shell" command.
1789 Note that no space is needed between "!" and SHELL COMMAND.
1793 watch EXPRESSION mask MASK_VALUE
1794 The watch command now supports the mask argument which allows creation
1795 of masked watchpoints, if the current architecture supports this feature.
1797 info auto-load-scripts [REGEXP]
1798 This command was formerly named "maintenance print section-scripts".
1799 It is now generally useful and is no longer a maintenance-only command.
1801 info macro [-all] [--] MACRO
1802 The info macro command has new options `-all' and `--'. The first for
1803 printing all definitions of a macro. The second for explicitly specifying
1804 the end of arguments and the beginning of the macro name in case the macro
1805 name starts with a hyphen.
1807 collect[/s] EXPRESSIONS
1808 The tracepoint collect command now takes an optional modifier "/s"
1809 that directs it to dereference pointer-to-character types and
1810 collect the bytes of memory up to a zero byte. The behavior is
1811 similar to what you see when you use the regular print command on a
1812 string. An optional integer following the "/s" sets a bound on the
1813 number of bytes that will be collected.
1816 The trace start command now interprets any supplied arguments as a
1817 note to be recorded with the trace run, with an effect similar to
1818 setting the variable trace-notes.
1821 The trace stop command now interprets any arguments as a note to be
1822 mentioned along with the tstatus report that the trace was stopped
1823 with a command. The effect is similar to setting the variable
1826 * Tracepoints can now be enabled and disabled at any time after a trace
1827 experiment has been started using the standard "enable" and "disable"
1828 commands. It is now possible to start a trace experiment with no enabled
1829 tracepoints; GDB will display a warning, but will allow the experiment to
1830 begin, assuming that tracepoints will be enabled as needed while the trace
1833 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1834 locations with 4-byte instructions, when they were previously
1835 limited to locations with instructions of 5 bytes or longer.
1839 set debug dwarf2-read
1840 show debug dwarf2-read
1841 Turns on or off display of debugging messages related to reading
1842 DWARF debug info. The default is off.
1844 set debug symtab-create
1845 show debug symtab-create
1846 Turns on or off display of debugging messages related to symbol table
1847 creation. The default is off.
1850 show extended-prompt
1851 Set the GDB prompt, and allow escape sequences to be inserted to
1852 display miscellaneous information (see 'help set extended-prompt'
1853 for the list of sequences). This prompt (and any information
1854 accessed through the escape sequences) is updated every time the
1855 prompt is displayed.
1857 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1858 show print entry-values
1859 Set printing of frame argument values at function entry. In some cases
1860 GDB can determine the value of function argument which was passed by the
1861 function caller, even if the value was modified inside the called function.
1863 set debug entry-values
1864 show debug entry-values
1865 Control display of debugging info for determining frame argument values at
1866 function entry and virtual tail call frames.
1868 set basenames-may-differ
1869 show basenames-may-differ
1870 Set whether a source file may have multiple base names.
1871 (A "base name" is the name of a file with the directory part removed.
1872 Example: The base name of "/home/user/hello.c" is "hello.c".)
1873 If set, GDB will canonicalize file names (e.g., expand symlinks)
1874 before comparing them. Canonicalization is an expensive operation,
1875 but it allows the same file be known by more than one base name.
1876 If not set (the default), all source files are assumed to have just
1877 one base name, and gdb will do file name comparisons more efficiently.
1883 Set a user name and notes for the current and any future trace runs.
1884 This is useful for long-running and/or disconnected traces, to
1885 inform others (or yourself) as to who is running the trace, supply
1886 contact information, or otherwise explain what is going on.
1888 set trace-stop-notes
1889 show trace-stop-notes
1890 Set a note attached to the trace run, that is displayed when the
1891 trace has been stopped by a tstop command. This is useful for
1892 instance as an explanation, if you are stopping a trace run that was
1893 started by someone else.
1895 * New remote packets
1899 Dynamically enable a tracepoint in a started trace experiment.
1903 Dynamically disable a tracepoint in a started trace experiment.
1907 Set the user and notes of the trace run.
1911 Query the current status of a tracepoint.
1915 Query the minimum length of instruction at which a fast tracepoint may
1918 * Dcache size (number of lines) and line-size are now runtime-configurable
1919 via "set dcache line" and "set dcache line-size" commands.
1923 Texas Instruments TMS320C6x tic6x-*-*
1927 Renesas RL78 rl78-*-elf
1929 *** Changes in GDB 7.3.1
1931 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1933 *** Changes in GDB 7.3
1935 * GDB has a new command: "thread find [REGEXP]".
1936 It finds the thread id whose name, target id, or thread extra info
1937 matches the given regular expression.
1939 * The "catch syscall" command now works on mips*-linux* targets.
1941 * The -data-disassemble MI command now supports modes 2 and 3 for
1942 dumping the instruction opcodes.
1944 * New command line options
1946 -data-directory DIR Specify DIR as the "data-directory".
1947 This is mostly for testing purposes.
1949 * The "maint set python auto-load on|off" command has been renamed to
1950 "set auto-load-scripts on|off".
1952 * GDB has a new command: "set directories".
1953 It is like the "dir" command except that it replaces the
1954 source path list instead of augmenting it.
1956 * GDB now understands thread names.
1958 On GNU/Linux, "info threads" will display the thread name as set by
1959 prctl or pthread_setname_np.
1961 There is also a new command, "thread name", which can be used to
1962 assign a name internally for GDB to display.
1965 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1966 has been integrated into GDB.
1970 ** The function gdb.Write now accepts an optional keyword 'stream'.
1971 This keyword, when provided, will direct the output to either
1972 stdout, stderr, or GDB's logging output.
1974 ** Parameters can now be be sub-classed in Python, and in particular
1975 you may implement the get_set_doc and get_show_doc functions.
1976 This improves how Parameter set/show documentation is processed
1977 and allows for more dynamic content.
1979 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1980 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1981 have an is_valid method.
1983 ** Breakpoints can now be sub-classed in Python, and in particular
1984 you may implement a 'stop' function that is executed each time
1985 the inferior reaches that breakpoint.
1987 ** New function gdb.lookup_global_symbol looks up a global symbol.
1989 ** GDB values in Python are now callable if the value represents a
1990 function. For example, if 'some_value' represents a function that
1991 takes two integer parameters and returns a value, you can call
1992 that function like so:
1994 result = some_value (10,20)
1996 ** Module gdb.types has been added.
1997 It contains a collection of utilities for working with gdb.Types objects:
1998 get_basic_type, has_field, make_enum_dict.
2000 ** Module gdb.printing has been added.
2001 It contains utilities for writing and registering pretty-printers.
2002 New classes: PrettyPrinter, SubPrettyPrinter,
2003 RegexpCollectionPrettyPrinter.
2004 New function: register_pretty_printer.
2006 ** New commands "info pretty-printers", "enable pretty-printer" and
2007 "disable pretty-printer" have been added.
2009 ** gdb.parameter("directories") is now available.
2011 ** New function gdb.newest_frame returns the newest frame in the
2014 ** The gdb.InferiorThread class has a new "name" attribute. This
2015 holds the thread's name.
2017 ** Python Support for Inferior events.
2018 Python scripts can add observers to be notified of events
2019 occurring in the process being debugged.
2020 The following events are currently supported:
2021 - gdb.events.cont Continue event.
2022 - gdb.events.exited Inferior exited event.
2023 - gdb.events.stop Signal received, and Breakpoint hit events.
2027 ** GDB now puts template parameters in scope when debugging in an
2028 instantiation. For example, if you have:
2030 template<int X> int func (void) { return X; }
2032 then if you step into func<5>, "print X" will show "5". This
2033 feature requires proper debuginfo support from the compiler; it
2034 was added to GCC 4.5.
2036 ** The motion commands "next", "finish", "until", and "advance" now
2037 work better when exceptions are thrown. In particular, GDB will
2038 no longer lose control of the inferior; instead, the GDB will
2039 stop the inferior at the point at which the exception is caught.
2040 This functionality requires a change in the exception handling
2041 code that was introduced in GCC 4.5.
2043 * GDB now follows GCC's rules on accessing volatile objects when
2044 reading or writing target state during expression evaluation.
2045 One notable difference to prior behavior is that "print x = 0"
2046 no longer generates a read of x; the value of the assignment is
2047 now always taken directly from the value being assigned.
2049 * GDB now has some support for using labels in the program's source in
2050 linespecs. For instance, you can use "advance label" to continue
2051 execution to a label.
2053 * GDB now has support for reading and writing a new .gdb_index
2054 section. This section holds a fast index of DWARF debugging
2055 information and can be used to greatly speed up GDB startup and
2056 operation. See the documentation for `save gdb-index' for details.
2058 * The "watch" command now accepts an optional "-location" argument.
2059 When used, this causes GDB to watch the memory referred to by the
2060 expression. Such a watchpoint is never deleted due to it going out
2063 * GDB now supports thread debugging of core dumps on GNU/Linux.
2065 GDB now activates thread debugging using the libthread_db library
2066 when debugging GNU/Linux core dumps, similarly to when debugging
2067 live processes. As a result, when debugging a core dump file, GDB
2068 is now able to display pthread_t ids of threads. For example, "info
2069 threads" shows the same output as when debugging the process when it
2070 was live. In earlier releases, you'd see something like this:
2073 * 1 LWP 6780 main () at main.c:10
2075 While now you see this:
2078 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2080 It is also now possible to inspect TLS variables when debugging core
2083 When debugging a core dump generated on a machine other than the one
2084 used to run GDB, you may need to point GDB at the correct
2085 libthread_db library with the "set libthread-db-search-path"
2086 command. See the user manual for more details on this command.
2088 * When natively debugging programs on PowerPC BookE processors running
2089 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2090 which stop execution of the inferior whenever it executes an instruction
2091 at any address within the specified range. See the "PowerPC Embedded"
2092 section in the user manual for more details.
2094 * New features in the GDB remote stub, GDBserver
2096 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2097 and i686 LynxOS (version 5.x).
2099 ** GDBserver is now supported on Blackfin Linux.
2101 * New native configurations
2103 ia64 HP-UX ia64-*-hpux*
2107 Analog Devices, Inc. Blackfin Processor bfin-*
2109 * Ada task switching is now supported on sparc-elf targets when
2110 debugging a program using the Ravenscar Profile. For more information,
2111 see the "Tasking Support when using the Ravenscar Profile" section
2112 in the GDB user manual.
2114 * Guile support was removed.
2116 * New features in the GNU simulator
2118 ** The --map-info flag lists all known core mappings.
2120 ** CFI flashes may be simulated via the "cfi" device.
2122 *** Changes in GDB 7.2
2124 * Shared library support for remote targets by default
2126 When GDB is configured for a generic, non-OS specific target, like
2127 for example, --target=arm-eabi or one of the many *-*-elf targets,
2128 GDB now queries remote stubs for loaded shared libraries using the
2129 `qXfer:libraries:read' packet. Previously, shared library support
2130 was always disabled for such configurations.
2134 ** Argument Dependent Lookup (ADL)
2136 In C++ ADL lookup directs function search to the namespaces of its
2137 arguments even if the namespace has not been imported.
2147 Here the compiler will search for `foo' in the namespace of 'b'
2148 and find A::foo. GDB now supports this. This construct is commonly
2149 used in the Standard Template Library for operators.
2151 ** Improved User Defined Operator Support
2153 In addition to member operators, GDB now supports lookup of operators
2154 defined in a namespace and imported with a `using' directive, operators
2155 defined in the global scope, operators imported implicitly from an
2156 anonymous namespace, and the ADL operators mentioned in the previous
2158 GDB now also supports proper overload resolution for all the previously
2159 mentioned flavors of operators.
2161 ** static const class members
2163 Printing of static const class members that are initialized in the
2164 class definition has been fixed.
2166 * Windows Thread Information Block access.
2168 On Windows targets, GDB now supports displaying the Windows Thread
2169 Information Block (TIB) structure. This structure is visible either
2170 by using the new command `info w32 thread-information-block' or, by
2171 dereferencing the new convenience variable named `$_tlb', a
2172 thread-specific pointer to the TIB. This feature is also supported
2173 when remote debugging using GDBserver.
2175 * Static tracepoints
2177 Static tracepoints are calls in the user program into a tracing
2178 library. One such library is a port of the LTTng kernel tracer to
2179 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2180 When debugging with GDBserver, GDB now supports combining the GDB
2181 tracepoint machinery with such libraries. For example: the user can
2182 use GDB to probe a static tracepoint marker (a call from the user
2183 program into the tracing library) with the new "strace" command (see
2184 "New commands" below). This creates a "static tracepoint" in the
2185 breakpoint list, that can be manipulated with the same feature set
2186 as fast and regular tracepoints. E.g., collect registers, local and
2187 global variables, collect trace state variables, and define
2188 tracepoint conditions. In addition, the user can collect extra
2189 static tracepoint marker specific data, by collecting the new
2190 $_sdata internal variable. When analyzing the trace buffer, you can
2191 inspect $_sdata like any other variable available to GDB. For more
2192 information, see the "Tracepoints" chapter in GDB user manual. New
2193 remote packets have been defined to support static tracepoints, see
2194 the "New remote packets" section below.
2196 * Better reconstruction of tracepoints after disconnected tracing
2198 GDB will attempt to download the original source form of tracepoint
2199 definitions when starting a trace run, and then will upload these
2200 upon reconnection to the target, resulting in a more accurate
2201 reconstruction of the tracepoints that are in use on the target.
2205 You can now exercise direct control over the ways that GDB can
2206 affect your program. For instance, you can disallow the setting of
2207 breakpoints, so that the program can run continuously (assuming
2208 non-stop mode). In addition, the "observer" variable is available
2209 to switch all of the different controls; in observer mode, GDB
2210 cannot affect the target's behavior at all, which is useful for
2211 tasks like diagnosing live systems in the field.
2213 * The new convenience variable $_thread holds the number of the
2216 * New remote packets
2220 Return the address of the Windows Thread Information Block of a given thread.
2224 In response to several of the tracepoint packets, the target may now
2225 also respond with a number of intermediate `qRelocInsn' request
2226 packets before the final result packet, to have GDB handle
2227 relocating an instruction to execute at a different address. This
2228 is particularly useful for stubs that support fast tracepoints. GDB
2229 reports support for this feature in the qSupported packet.
2233 List static tracepoint markers in the target program.
2237 List static tracepoint markers at a given address in the target
2240 qXfer:statictrace:read
2242 Read the static trace data collected (by a `collect $_sdata'
2243 tracepoint action). The remote stub reports support for this packet
2244 to gdb's qSupported query.
2248 Send the current settings of GDB's permission flags.
2252 Send part of the source (textual) form of a tracepoint definition,
2253 which includes location, conditional, and action list.
2255 * The source command now accepts a -s option to force searching for the
2256 script in the source search path even if the script name specifies
2259 * New features in the GDB remote stub, GDBserver
2261 - GDBserver now support tracepoints (including fast tracepoints, and
2262 static tracepoints). The feature is currently supported by the
2263 i386-linux and amd64-linux builds. See the "Tracepoints support
2264 in gdbserver" section in the manual for more information.
2266 GDBserver JIT compiles the tracepoint's conditional agent
2267 expression bytecode into native code whenever possible for low
2268 overhead dynamic tracepoints conditionals. For such tracepoints,
2269 an expression that examines program state is evaluated when the
2270 tracepoint is reached, in order to determine whether to capture
2271 trace data. If the condition is simple and false, processing the
2272 tracepoint finishes very quickly and no data is gathered.
2274 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2275 for static tracepoints support.
2277 - GDBserver now supports x86_64 Windows 64-bit debugging.
2279 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2280 it understands register description.
2282 * The --batch flag now disables pagination and queries.
2284 * X86 general purpose registers
2286 GDB now supports reading/writing byte, word and double-word x86
2287 general purpose registers directly. This means you can use, say,
2288 $ah or $ax to refer, respectively, to the byte register AH and
2289 16-bit word register AX that are actually portions of the 32-bit
2290 register EAX or 64-bit register RAX.
2292 * The `commands' command now accepts a range of breakpoints to modify.
2293 A plain `commands' following a command that creates multiple
2294 breakpoints affects all the breakpoints set by that command. This
2295 applies to breakpoints set by `rbreak', and also applies when a
2296 single `break' command creates multiple breakpoints (e.g.,
2297 breakpoints on overloaded c++ functions).
2299 * The `rbreak' command now accepts a filename specification as part of
2300 its argument, limiting the functions selected by the regex to those
2301 in the specified file.
2303 * Support for remote debugging Windows and SymbianOS shared libraries
2304 from Unix hosts has been improved. Non Windows GDB builds now can
2305 understand target reported file names that follow MS-DOS based file
2306 system semantics, such as file names that include drive letters and
2307 use the backslash character as directory separator. This makes it
2308 possible to transparently use the "set sysroot" and "set
2309 solib-search-path" on Unix hosts to point as host copies of the
2310 target's shared libraries. See the new command "set
2311 target-file-system-kind" described below, and the "Commands to
2312 specify files" section in the user manual for more information.
2316 eval template, expressions...
2317 Convert the values of one or more expressions under the control
2318 of the string template to a command line, and call it.
2320 set target-file-system-kind unix|dos-based|auto
2321 show target-file-system-kind
2322 Set or show the assumed file system kind for target reported file
2325 save breakpoints <filename>
2326 Save all current breakpoint definitions to a file suitable for use
2327 in a later debugging session. To read the saved breakpoint
2328 definitions, use the `source' command.
2330 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2333 info static-tracepoint-markers
2334 Display information about static tracepoint markers in the target.
2336 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2337 Define a static tracepoint by probing a marker at the given
2338 function, line, address, or marker ID.
2342 Enable and disable observer mode.
2344 set may-write-registers on|off
2345 set may-write-memory on|off
2346 set may-insert-breakpoints on|off
2347 set may-insert-tracepoints on|off
2348 set may-insert-fast-tracepoints on|off
2349 set may-interrupt on|off
2350 Set individual permissions for GDB effects on the target. Note that
2351 some of these settings can have undesirable or surprising
2352 consequences, particularly when changed in the middle of a session.
2353 For instance, disabling the writing of memory can prevent
2354 breakpoints from being inserted, cause single-stepping to fail, or
2355 even crash your program, if you disable after breakpoints have been
2356 inserted. However, GDB should not crash.
2358 set record memory-query on|off
2359 show record memory-query
2360 Control whether to stop the inferior if memory changes caused
2361 by an instruction cannot be recorded.
2366 The disassemble command now supports "start,+length" form of two arguments.
2370 ** GDB now provides a new directory location, called the python directory,
2371 where Python scripts written for GDB can be installed. The location
2372 of that directory is <data-directory>/python, where <data-directory>
2373 is the GDB data directory. For more details, see section `Scripting
2374 GDB using Python' in the manual.
2376 ** The GDB Python API now has access to breakpoints, symbols, symbol
2377 tables, program spaces, inferiors, threads and frame's code blocks.
2378 Additionally, GDB Parameters can now be created from the API, and
2379 manipulated via set/show in the CLI.
2381 ** New functions gdb.target_charset, gdb.target_wide_charset,
2382 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2384 ** New exception gdb.GdbError.
2386 ** Pretty-printers are now also looked up in the current program space.
2388 ** Pretty-printers can now be individually enabled and disabled.
2390 ** GDB now looks for names of Python scripts to auto-load in a
2391 special section named `.debug_gdb_scripts', in addition to looking
2392 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2394 * Tracepoint actions were unified with breakpoint commands. In particular,
2395 there are no longer differences in "info break" output for breakpoints and
2396 tracepoints and the "commands" command can be used for both tracepoints and
2397 regular breakpoints.
2401 ARM Symbian arm*-*-symbianelf*
2403 * D language support.
2404 GDB now supports debugging programs written in the D programming
2407 * GDB now supports the extended ptrace interface for PowerPC which is
2408 available since Linux kernel version 2.6.34. This automatically enables
2409 any hardware breakpoints and additional hardware watchpoints available in
2410 the processor. The old ptrace interface exposes just one hardware
2411 watchpoint and no hardware breakpoints.
2413 * GDB is now able to use the Data Value Compare (DVC) register available on
2414 embedded PowerPC processors to implement in hardware simple watchpoint
2415 conditions of the form:
2417 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2419 This works in native GDB running on Linux kernels with the extended ptrace
2420 interface mentioned above.
2422 *** Changes in GDB 7.1
2426 ** Namespace Support
2428 GDB now supports importing of namespaces in C++. This enables the
2429 user to inspect variables from imported namespaces. Support for
2430 namepace aliasing has also been added. So, if a namespace is
2431 aliased in the current scope (e.g. namepace C=A; ) the user can
2432 print variables using the alias (e.g. (gdb) print C::x).
2436 All known bugs relating to the printing of virtual base class were
2437 fixed. It is now possible to call overloaded static methods using a
2442 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2443 and reinterpret_cast<> are now handled by the C++ expression parser.
2447 Xilinx MicroBlaze microblaze-*-*
2452 Xilinx MicroBlaze microblaze
2455 * Multi-program debugging.
2457 GDB now has support for multi-program (a.k.a. multi-executable or
2458 multi-exec) debugging. This allows for debugging multiple inferiors
2459 simultaneously each running a different program under the same GDB
2460 session. See "Debugging Multiple Inferiors and Programs" in the
2461 manual for more information. This implied some user visible changes
2462 in the multi-inferior support. For example, "info inferiors" now
2463 lists inferiors that are not running yet or that have exited
2464 already. See also "New commands" and "New options" below.
2466 * New tracing features
2468 GDB's tracepoint facility now includes several new features:
2470 ** Trace state variables
2472 GDB tracepoints now include support for trace state variables, which
2473 are variables managed by the target agent during a tracing
2474 experiment. They are useful for tracepoints that trigger each
2475 other, so for instance one tracepoint can count hits in a variable,
2476 and then a second tracepoint has a condition that is true when the
2477 count reaches a particular value. Trace state variables share the
2478 $-syntax of GDB convenience variables, and can appear in both
2479 tracepoint actions and condition expressions. Use the "tvariable"
2480 command to create, and "info tvariables" to view; see "Trace State
2481 Variables" in the manual for more detail.
2485 GDB now includes an option for defining fast tracepoints, which
2486 targets may implement more efficiently, such as by installing a jump
2487 into the target agent rather than a trap instruction. The resulting
2488 speedup can be by two orders of magnitude or more, although the
2489 tradeoff is that some program locations on some target architectures
2490 might not allow fast tracepoint installation, for instance if the
2491 instruction to be replaced is shorter than the jump. To request a
2492 fast tracepoint, use the "ftrace" command, with syntax identical to
2493 the regular trace command.
2495 ** Disconnected tracing
2497 It is now possible to detach GDB from the target while it is running
2498 a trace experiment, then reconnect later to see how the experiment
2499 is going. In addition, a new variable disconnected-tracing lets you
2500 tell the target agent whether to continue running a trace if the
2501 connection is lost unexpectedly.
2505 GDB now has the ability to save the trace buffer into a file, and
2506 then use that file as a target, similarly to you can do with
2507 corefiles. You can select trace frames, print data that was
2508 collected in them, and use tstatus to display the state of the
2509 tracing run at the moment that it was saved. To create a trace
2510 file, use "tsave <filename>", and to use it, do "target tfile
2513 ** Circular trace buffer
2515 You can ask the target agent to handle the trace buffer as a
2516 circular buffer, discarding the oldest trace frames to make room for
2517 newer ones, by setting circular-trace-buffer to on. This feature may
2518 not be available for all target agents.
2523 The disassemble command, when invoked with two arguments, now requires
2524 the arguments to be comma-separated.
2527 The info variables command now displays variable definitions. Files
2528 which only declare a variable are not shown.
2531 The source command is now capable of sourcing Python scripts.
2532 This feature is dependent on the debugger being build with Python
2535 Related to this enhancement is also the introduction of a new command
2536 "set script-extension" (see below).
2538 * New commands (for set/show, see "New options" below)
2540 record save [<FILENAME>]
2541 Save a file (in core file format) containing the process record
2542 execution log for replay debugging at a later time.
2544 record restore <FILENAME>
2545 Restore the process record execution log that was saved at an
2546 earlier time, for replay debugging.
2548 add-inferior [-copies <N>] [-exec <FILENAME>]
2551 clone-inferior [-copies <N>] [ID]
2552 Make a new inferior ready to execute the same program another
2553 inferior has loaded.
2558 maint info program-spaces
2559 List the program spaces loaded into GDB.
2561 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2562 show remote interrupt-sequence
2563 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2564 as the sequence to the remote target in order to interrupt the execution.
2565 Ctrl-C is a default. Some system prefers BREAK which is high level of
2566 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2567 Magic SysRq g. It is BREAK signal and character 'g'.
2569 set remote interrupt-on-connect [on | off]
2570 show remote interrupt-on-connect
2571 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2572 remote target when gdb connects to it. This is needed when you debug
2575 set remotebreak [on | off]
2577 Deprecated. Use "set/show remote interrupt-sequence" instead.
2579 tvariable $NAME [ = EXP ]
2580 Create or modify a trace state variable.
2583 List trace state variables and their values.
2585 delete tvariable $NAME ...
2586 Delete one or more trace state variables.
2589 Evaluate the given expressions without collecting anything into the
2590 trace buffer. (Valid in tracepoint actions only.)
2592 ftrace FN / FILE:LINE / *ADDR
2593 Define a fast tracepoint at the given function, line, or address.
2595 * New expression syntax
2597 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2598 GDB now parses 0b101010 identically with 42.
2602 set follow-exec-mode new|same
2603 show follow-exec-mode
2604 Control whether GDB reuses the same inferior across an exec call or
2605 creates a new one. This is useful to be able to restart the old
2606 executable after the inferior having done an exec call.
2608 set default-collect EXPR, ...
2609 show default-collect
2610 Define a list of expressions to be collected at each tracepoint.
2611 This is a useful way to ensure essential items are not overlooked,
2612 such as registers or a critical global variable.
2614 set disconnected-tracing
2615 show disconnected-tracing
2616 If set to 1, the target is instructed to continue tracing if it
2617 loses its connection to GDB. If 0, the target is to stop tracing
2620 set circular-trace-buffer
2621 show circular-trace-buffer
2622 If set to on, the target is instructed to use a circular trace buffer
2623 and discard the oldest trace frames instead of stopping the trace due
2624 to a full trace buffer. If set to off, the trace stops when the buffer
2625 fills up. Some targets may not support this.
2627 set script-extension off|soft|strict
2628 show script-extension
2629 If set to "off", the debugger does not perform any script language
2630 recognition, and all sourced files are assumed to be GDB scripts.
2631 If set to "soft" (the default), files are sourced according to
2632 filename extension, falling back to GDB scripts if the first
2634 If set to "strict", files are sourced according to filename extension.
2636 set ada trust-PAD-over-XVS on|off
2637 show ada trust-PAD-over-XVS
2638 If off, activate a workaround against a bug in the debugging information
2639 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2640 the GCC sources for more information about the GNAT encoding and
2641 PAD types in particular). It is always safe to set this option to
2642 off, but this introduces a slight performance penalty. The default
2645 * Python API Improvements
2647 ** GDB provides the new class gdb.LazyString. This is useful in
2648 some pretty-printing cases. The new method gdb.Value.lazy_string
2649 provides a simple way to create objects of this type.
2651 ** The fields returned by gdb.Type.fields now have an
2652 `is_base_class' attribute.
2654 ** The new method gdb.Type.range returns the range of an array type.
2656 ** The new method gdb.parse_and_eval can be used to parse and
2657 evaluate an expression.
2659 * New remote packets
2662 Define a trace state variable.
2665 Get the current value of a trace state variable.
2668 Set desired tracing behavior upon disconnection.
2671 Set the trace buffer to be linear or circular.
2674 Get data about the tracepoints currently in use.
2678 Process record now works correctly with hardware watchpoints.
2680 Multiple bug fixes have been made to the mips-irix port, making it
2681 much more reliable. In particular:
2682 - Debugging threaded applications is now possible again. Previously,
2683 GDB would hang while starting the program, or while waiting for
2684 the program to stop at a breakpoint.
2685 - Attaching to a running process no longer hangs.
2686 - An error occurring while loading a core file has been fixed.
2687 - Changing the value of the PC register now works again. This fixes
2688 problems observed when using the "jump" command, or when calling
2689 a function from GDB, or even when assigning a new value to $pc.
2690 - With the "finish" and "return" commands, the return value for functions
2691 returning a small array is now correctly printed.
2692 - It is now possible to break on shared library code which gets executed
2693 during a shared library init phase (code executed while executing
2694 their .init section). Previously, the breakpoint would have no effect.
2695 - GDB is now able to backtrace through the signal handler for
2696 non-threaded programs.
2698 PIE (Position Independent Executable) programs debugging is now supported.
2699 This includes debugging execution of PIC (Position Independent Code) shared
2700 libraries although for that, it should be possible to run such libraries as an
2703 *** Changes in GDB 7.0
2705 * GDB now has an interface for JIT compilation. Applications that
2706 dynamically generate code can create symbol files in memory and register
2707 them with GDB. For users, the feature should work transparently, and
2708 for JIT developers, the interface is documented in the GDB manual in the
2709 "JIT Compilation Interface" chapter.
2711 * Tracepoints may now be conditional. The syntax is as for
2712 breakpoints; either an "if" clause appended to the "trace" command,
2713 or the "condition" command is available. GDB sends the condition to
2714 the target for evaluation using the same bytecode format as is used
2715 for tracepoint actions.
2717 * The disassemble command now supports: an optional /r modifier, print the
2718 raw instructions in hex as well as in symbolic form, and an optional /m
2719 modifier to print mixed source+assembly.
2721 * Process record and replay
2723 In a architecture environment that supports ``process record and
2724 replay'', ``process record and replay'' target can record a log of
2725 the process execution, and replay it with both forward and reverse
2728 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2729 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2730 set execution-direction {forward|reverse}, for targets that support
2733 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2734 feature is available with a native GDB running on kernel version
2737 * GDB now has support for multi-byte and wide character sets on the
2738 target. Strings whose character type is wchar_t, char16_t, or
2739 char32_t are now correctly printed. GDB supports wide- and unicode-
2740 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2741 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2742 `printf'. This feature requires iconv to work properly; if your
2743 system does not have a working iconv, GDB can use GNU libiconv. See
2744 the installation instructions for more information.
2746 * GDB now supports automatic retrieval of shared library files from
2747 remote targets. To use this feature, specify a system root that begins
2748 with the `remote:' prefix, either via the `set sysroot' command or via
2749 the `--with-sysroot' configure-time option.
2751 * "info sharedlibrary" now takes an optional regex of libraries to show,
2752 and it now reports if a shared library has no debugging information.
2754 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2755 now complete on file names.
2757 * When completing in expressions, gdb will attempt to limit
2758 completions to allowable structure or union fields, where appropriate.
2759 For instance, consider:
2761 # struct example { int f1; double f2; };
2762 # struct example variable;
2765 If the user types TAB at the end of this command line, the available
2766 completions will be "f1" and "f2".
2768 * Inlined functions are now supported. They show up in backtraces, and
2769 the "step", "next", and "finish" commands handle them automatically.
2771 * GDB now supports the token-splicing (##) and stringification (#)
2772 operators when expanding macros. It also supports variable-arity
2775 * GDB now supports inspecting extra signal information, exported by
2776 the new $_siginfo convenience variable. The feature is currently
2777 implemented on linux ARM, i386 and amd64.
2779 * GDB can now display the VFP floating point registers and NEON vector
2780 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2781 can provide these registers (requires Linux 2.6.30 or later). Remote
2782 and simulator targets may also provide them.
2784 * New remote packets
2787 Search memory for a sequence of bytes.
2790 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2791 operation over reliable transport links. Use of this packet is
2792 controlled by the `set remote noack-packet' command.
2795 Kill the process with the specified process ID. Use this in preference
2796 to `k' when multiprocess protocol extensions are supported.
2799 Obtains additional operating system information
2803 Read or write additional signal information.
2805 * Removed remote protocol undocumented extension
2807 An undocumented extension to the remote protocol's `S' stop reply
2808 packet that permited the stub to pass a process id was removed.
2809 Remote servers should use the `T' stop reply packet instead.
2811 * GDB now supports multiple function calling conventions according to the
2812 DWARF-2 DW_AT_calling_convention function attribute.
2814 * The SH target utilizes the aforementioned change to distinguish between gcc
2815 and Renesas calling convention. It also adds the new CLI commands
2816 `set/show sh calling-convention'.
2818 * GDB can now read compressed debug sections, as produced by GNU gold
2819 with the --compress-debug-sections=zlib flag.
2821 * 64-bit core files are now supported on AIX.
2823 * Thread switching is now supported on Tru64.
2825 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2826 which will be allocated using malloc later in program execution.
2828 * The qXfer:libraries:read remote procotol packet now allows passing a
2829 list of section offsets.
2831 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2832 conditions handling signals delivered during attach or thread creation
2833 have also been fixed.
2835 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2836 From the user's standpoint, all unqualified instances of True and False
2837 are treated as the standard definitions, regardless of context.
2839 * GDB now parses C++ symbol and type names more flexibly. For
2842 template<typename T> class C { };
2845 GDB will now correctly handle all of:
2847 ptype C<char const *>
2848 ptype C<char const*>
2849 ptype C<const char *>
2850 ptype C<const char*>
2852 * New features in the GDB remote stub, gdbserver
2854 - The "--wrapper" command-line argument tells gdbserver to use a
2855 wrapper program to launch programs for debugging.
2857 - On PowerPC and S/390 targets, it is now possible to use a single
2858 gdbserver executable to debug both 32-bit and 64-bit programs.
2859 (This requires gdbserver itself to be built as a 64-bit executable.)
2861 - gdbserver uses the new noack protocol mode for TCP connections to
2862 reduce communications latency, if also supported and enabled in GDB.
2864 - Support for the sparc64-linux-gnu target is now included in
2867 - The amd64-linux build of gdbserver now supports debugging both
2868 32-bit and 64-bit programs.
2870 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2871 now support hardware watchpoints, and will use them automatically
2876 GDB now has support for scripting using Python. Whether this is
2877 available is determined at configure time.
2879 New GDB commands can now be written in Python.
2881 * Ada tasking support
2883 Ada tasks can now be inspected in GDB. The following commands have
2887 Print the list of Ada tasks.
2889 Print detailed information about task number N.
2891 Print the task number of the current task.
2893 Switch the context of debugging to task number N.
2895 * Support for user-defined prefixed commands. The "define" command can
2896 add new commands to existing prefixes, e.g. "target".
2898 * Multi-inferior, multi-process debugging.
2900 GDB now has generalized support for multi-inferior debugging. See
2901 "Debugging Multiple Inferiors" in the manual for more information.
2902 Although availability still depends on target support, the command
2903 set is more uniform now. The GNU/Linux specific multi-forks support
2904 has been migrated to this new framework. This implied some user
2905 visible changes; see "New commands" and also "Removed commands"
2908 * Target descriptions can now describe the target OS ABI. See the
2909 "Target Description Format" section in the user manual for more
2912 * Target descriptions can now describe "compatible" architectures
2913 to indicate that the target can execute applications for a different
2914 architecture in addition to those for the main target architecture.
2915 See the "Target Description Format" section in the user manual for
2918 * Multi-architecture debugging.
2920 GDB now includes general supports for debugging applications on
2921 hybrid systems that use more than one single processor architecture
2922 at the same time. Each such hybrid architecture still requires
2923 specific support to be added. The only hybrid architecture supported
2924 in this version of GDB is the Cell Broadband Engine.
2926 * GDB now supports integrated debugging of Cell/B.E. applications that
2927 use both the PPU and SPU architectures. To enable support for hybrid
2928 Cell/B.E. debugging, you need to configure GDB to support both the
2929 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2930 --enable-targets configure option.
2932 * Non-stop mode debugging.
2934 For some targets, GDB now supports an optional mode of operation in
2935 which you can examine stopped threads while other threads continue
2936 to execute freely. This is referred to as non-stop mode, with the
2937 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2938 section in the user manual for more information.
2940 To be able to support remote non-stop debugging, a remote stub needs
2941 to implement the non-stop mode remote protocol extensions, as
2942 described in the "Remote Non-Stop" section of the user manual. The
2943 GDB remote stub, gdbserver, has been adjusted to support these
2944 extensions on linux targets.
2946 * New commands (for set/show, see "New options" below)
2948 catch syscall [NAME(S) | NUMBER(S)]
2949 Catch system calls. Arguments, which should be names of system
2950 calls or their numbers, mean catch only those syscalls. Without
2951 arguments, every syscall will be caught. When the inferior issues
2952 any of the specified syscalls, GDB will stop and announce the system
2953 call, both when it is called and when its call returns. This
2954 feature is currently available with a native GDB running on the
2955 Linux Kernel, under the following architectures: x86, x86_64,
2956 PowerPC and PowerPC64.
2958 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2960 Search memory for a sequence of bytes.
2962 maint set python print-stack
2963 maint show python print-stack
2964 Show a stack trace when an error is encountered in a Python script.
2967 Invoke CODE by passing it to the Python interpreter.
2972 These allow macros to be defined, undefined, and listed
2976 Show operating system information about processes.
2979 List the inferiors currently under GDB's control.
2982 Switch focus to inferior number NUM.
2985 Detach from inferior number NUM.
2988 Kill inferior number NUM.
2992 set spu stop-on-load
2993 show spu stop-on-load
2994 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2996 set spu auto-flush-cache
2997 show spu auto-flush-cache
2998 Control whether to automatically flush the software-managed cache
2999 during Cell/B.E. debugging.
3001 set sh calling-convention
3002 show sh calling-convention
3003 Control the calling convention used when calling SH target functions.
3006 show debug timestamp
3007 Control display of timestamps with GDB debugging output.
3009 set disassemble-next-line
3010 show disassemble-next-line
3011 Control display of disassembled source lines or instructions when
3014 set remote noack-packet
3015 show remote noack-packet
3016 Set/show the use of remote protocol QStartNoAckMode packet. See above
3017 under "New remote packets."
3019 set remote query-attached-packet
3020 show remote query-attached-packet
3021 Control use of remote protocol `qAttached' (query-attached) packet.
3023 set remote read-siginfo-object
3024 show remote read-siginfo-object
3025 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3028 set remote write-siginfo-object
3029 show remote write-siginfo-object
3030 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3033 set remote reverse-continue
3034 show remote reverse-continue
3035 Control use of remote protocol 'bc' (reverse-continue) packet.
3037 set remote reverse-step
3038 show remote reverse-step
3039 Control use of remote protocol 'bs' (reverse-step) packet.
3041 set displaced-stepping
3042 show displaced-stepping
3043 Control displaced stepping mode. Displaced stepping is a way to
3044 single-step over breakpoints without removing them from the debuggee.
3045 Also known as "out-of-line single-stepping".
3048 show debug displaced
3049 Control display of debugging info for displaced stepping.
3051 maint set internal-error
3052 maint show internal-error
3053 Control what GDB does when an internal error is detected.
3055 maint set internal-warning
3056 maint show internal-warning
3057 Control what GDB does when an internal warning is detected.
3062 Use a wrapper program to launch programs for debugging.
3064 set multiple-symbols (all|ask|cancel)
3065 show multiple-symbols
3066 The value of this variable can be changed to adjust the debugger behavior
3067 when an expression or a breakpoint location contains an ambiguous symbol
3068 name (an overloaded function name, for instance).
3070 set breakpoint always-inserted
3071 show breakpoint always-inserted
3072 Keep breakpoints always inserted in the target, as opposed to inserting
3073 them when resuming the target, and removing them when the target stops.
3074 This option can improve debugger performance on slow remote targets.
3076 set arm fallback-mode (arm|thumb|auto)
3077 show arm fallback-mode
3078 set arm force-mode (arm|thumb|auto)
3080 These commands control how ARM GDB determines whether instructions
3081 are ARM or Thumb. The default for both settings is auto, which uses
3082 the current CPSR value for instructions without symbols; previous
3083 versions of GDB behaved as if "set arm fallback-mode arm".
3085 set disable-randomization
3086 show disable-randomization
3087 Standalone programs run with the virtual address space randomization enabled
3088 by default on some platforms. This option keeps the addresses stable across
3089 multiple debugging sessions.
3093 Control whether other threads are stopped or not when some thread hits
3098 Requests that asynchronous execution is enabled in the target, if available.
3099 In this case, it's possible to resume target in the background, and interact
3100 with GDB while the target is running. "show target-async" displays the
3101 current state of asynchronous execution of the target.
3103 set target-wide-charset
3104 show target-wide-charset
3105 The target-wide-charset is the name of the character set that GDB
3106 uses when printing characters whose type is wchar_t.
3108 set tcp auto-retry (on|off)
3110 set tcp connect-timeout
3111 show tcp connect-timeout
3112 These commands allow GDB to retry failed TCP connections to a remote stub
3113 with a specified timeout period; this is useful if the stub is launched
3114 in parallel with GDB but may not be ready to accept connections immediately.
3116 set libthread-db-search-path
3117 show libthread-db-search-path
3118 Control list of directories which GDB will search for appropriate
3121 set schedule-multiple (on|off)
3122 show schedule-multiple
3123 Allow GDB to resume all threads of all processes or only threads of
3124 the current process.
3128 Use more aggressive caching for accesses to the stack. This improves
3129 performance of remote debugging (particularly backtraces) without
3130 affecting correctness.
3132 set interactive-mode (on|off|auto)
3133 show interactive-mode
3134 Control whether GDB runs in interactive mode (on) or not (off).
3135 When in interactive mode, GDB waits for the user to answer all
3136 queries. Otherwise, GDB does not wait and assumes the default
3137 answer. When set to auto (the default), GDB determines which
3138 mode to use based on the stdin settings.
3143 For program forks, this is replaced by the new more generic `info
3144 inferiors' command. To list checkpoints, you can still use the
3145 `info checkpoints' command, which was an alias for the `info forks'
3149 Replaced by the new `inferior' command. To switch between
3150 checkpoints, you can still use the `restart' command, which was an
3151 alias for the `fork' command.
3154 This is removed, since some targets don't have a notion of
3155 processes. To switch between processes, you can still use the
3156 `inferior' command using GDB's own inferior number.
3159 For program forks, this is replaced by the new more generic `kill
3160 inferior' command. To delete a checkpoint, you can still use the
3161 `delete checkpoint' command, which was an alias for the `delete
3165 For program forks, this is replaced by the new more generic `detach
3166 inferior' command. To detach a checkpoint, you can still use the
3167 `detach checkpoint' command, which was an alias for the `detach
3170 * New native configurations
3172 x86/x86_64 Darwin i[34567]86-*-darwin*
3174 x86_64 MinGW x86_64-*-mingw*
3178 Lattice Mico32 lm32-*
3179 x86 DICOS i[34567]86-*-dicos*
3180 x86_64 DICOS x86_64-*-dicos*
3183 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3184 (mingw32ce) debugging.
3190 These commands were actually not implemented on any target.
3192 *** Changes in GDB 6.8
3194 * New native configurations
3196 NetBSD/hppa hppa*-*netbsd*
3197 Xtensa GNU/Linux xtensa*-*-linux*
3201 NetBSD/hppa hppa*-*-netbsd*
3202 Xtensa GNU/Lunux xtensa*-*-linux*
3204 * Change in command line behavior -- corefiles vs. process ids.
3206 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3207 attaching to process NUMBER fails, GDB no longer attempts to open a
3208 core file named NUMBER. Attaching to a program using the -c option
3209 is no longer supported. Instead, use the '-p' or '--pid' options.
3211 * GDB can now be built as a native debugger for debugging Windows x86
3212 (mingw32) Portable Executable (PE) programs.
3214 * Pending breakpoints no longer change their number when their address
3217 * GDB now supports breakpoints with multiple locations,
3218 including breakpoints on C++ constructors, inside C++ templates,
3219 and in inlined functions.
3221 * GDB's ability to debug optimized code has been improved. GDB more
3222 accurately identifies function bodies and lexical blocks that occupy
3223 more than one contiguous range of addresses.
3225 * Target descriptions can now describe registers for PowerPC.
3227 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3228 registers on PowerPC targets.
3230 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3231 targets even when the libthread_db library is not available.
3233 * The GDB remote stub, gdbserver, now supports the new file transfer
3234 commands (remote put, remote get, and remote delete).
3236 * The GDB remote stub, gdbserver, now supports run and attach in
3237 extended-remote mode.
3239 * hppa*64*-*-hpux11* target broken
3240 The debugger is unable to start a program and fails with the following
3241 error: "Error trying to get information about dynamic linker".
3242 The gdb-6.7 release is also affected.
3244 * GDB now supports the --enable-targets= configure option to allow
3245 building a single GDB executable that supports multiple remote
3246 target architectures.
3248 * GDB now supports debugging C and C++ programs which use the
3249 Decimal Floating Point extension. In addition, the PowerPC target
3250 now has a set of pseudo-registers to inspect decimal float values
3251 stored in two consecutive float registers.
3253 * The -break-insert MI command can optionally create pending
3256 * Improved support for debugging Ada
3257 Many improvements to the Ada language support have been made. These
3259 - Better support for Ada2005 interface types
3260 - Improved handling of arrays and slices in general
3261 - Better support for Taft-amendment types
3262 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3264 - Improved command completion in Ada
3267 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3272 set print frame-arguments (all|scalars|none)
3273 show print frame-arguments
3274 The value of this variable can be changed to control which argument
3275 values should be printed by the debugger when displaying a frame.
3280 Transfer files to and from a remote target, and delete remote files.
3287 Transfer files to and from a remote target, and delete remote files.
3289 * New remote packets
3296 Open, close, read, write, and delete files on the remote system.
3299 Attach to an existing process on the remote system, in extended-remote
3303 Run a new process on the remote system, in extended-remote mode.
3305 *** Changes in GDB 6.7
3307 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3308 bfd, libiberty and opcodes, as revealed by static analysis donated by
3309 Coverity, Inc. (http://scan.coverity.com).
3311 * When looking up multiply-defined global symbols, GDB will now prefer the
3312 symbol definition in the current shared library if it was built using the
3313 -Bsymbolic linker option.
3315 * When the Text User Interface (TUI) is not configured, GDB will now
3316 recognize the -tui command-line option and print a message that the TUI
3319 * The GDB remote stub, gdbserver, now has lower overhead for high
3320 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3322 * GDB for MIPS targets now autodetects whether a remote target provides
3323 32-bit or 64-bit register values.
3325 * Support for C++ member pointers has been improved.
3327 * GDB now understands XML target descriptions, which specify the
3328 target's overall architecture. GDB can read a description from
3329 a local file or over the remote serial protocol.
3331 * Vectors of single-byte data use a new integer type which is not
3332 automatically displayed as character or string data.
3334 * The /s format now works with the print command. It displays
3335 arrays of single-byte integers and pointers to single-byte integers
3338 * Target descriptions can now describe target-specific registers,
3339 for architectures which have implemented the support (currently
3340 only ARM, M68K, and MIPS).
3342 * GDB and the GDB remote stub, gdbserver, now support the XScale
3345 * The GDB remote stub, gdbserver, has been updated to support
3346 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3347 has been rewritten to use the standard GDB remote protocol.
3349 * GDB can now step into C++ functions which are called through thunks.
3351 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3353 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3354 layout. It also supports a TextSeg= and DataSeg= response when only
3355 segment base addresses (rather than offsets) are available.
3357 * The /i format now outputs any trailing branch delay slot instructions
3358 immediately following the last instruction within the count specified.
3360 * The GDB remote protocol "T" stop reply packet now supports a
3361 "library" response. Combined with the new "qXfer:libraries:read"
3362 packet, this response allows GDB to debug shared libraries on targets
3363 where the operating system manages the list of loaded libraries (e.g.
3364 Windows and SymbianOS).
3366 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3367 (DLLs) on Windows and Windows CE targets.
3369 * GDB now supports a faster verification that a .debug file matches its binary
3370 according to its build-id signature, if the signature is present.
3376 Enable or disable hardware flow control (RTS/CTS) on the serial port
3377 when debugging using remote targets.
3379 set mem inaccessible-by-default
3380 show mem inaccessible-by-default
3381 If the target supplies a memory map, for instance via the remote
3382 protocol's "qXfer:memory-map:read" packet, setting this variable
3383 prevents GDB from accessing memory outside the memory map. This
3384 is useful for targets with memory mapped registers or which react
3385 badly to accesses of unmapped address space.
3387 set breakpoint auto-hw
3388 show breakpoint auto-hw
3389 If the target supplies a memory map, for instance via the remote
3390 protocol's "qXfer:memory-map:read" packet, setting this variable
3391 lets GDB use hardware breakpoints automatically for memory regions
3392 where it can not use software breakpoints. This covers both the
3393 "break" command and internal breakpoints used for other commands
3394 including "next" and "finish".
3397 catch exception unhandled
3398 Stop the program execution when Ada exceptions are raised.
3401 Stop the program execution when an Ada assertion failed.
3405 Set an alternate system root for target files. This is a more
3406 general version of "set solib-absolute-prefix", which is now
3407 an alias to "set sysroot".
3410 Provide extended SPU facility status information. This set of
3411 commands is available only when debugging the Cell/B.E. SPU
3414 * New native configurations
3416 OpenBSD/sh sh*-*openbsd*
3419 unset tdesc filename
3421 Use the specified local file as an XML target description, and do
3422 not query the target for its built-in description.
3426 OpenBSD/sh sh*-*-openbsd*
3427 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3428 Toshiba Media Processor mep-elf
3430 * New remote packets
3433 Ignore the specified signals; pass them directly to the debugged program
3434 without stopping other threads or reporting them to GDB.
3436 qXfer:features:read:
3437 Read an XML target description from the target, which describes its
3442 Read or write contents of an spufs file on the target system. These
3443 packets are available only on the Cell/B.E. SPU architecture.
3445 qXfer:libraries:read:
3446 Report the loaded shared libraries. Combined with new "T" packet
3447 response, this packet allows GDB to debug shared libraries on
3448 targets where the operating system manages the list of loaded
3449 libraries (e.g. Windows and SymbianOS).
3453 Support for these obsolete configurations has been removed.
3461 i[34567]86-*-lynxos*
3462 i[34567]86-*-netware*
3463 i[34567]86-*-sco3.2v5*
3464 i[34567]86-*-sco3.2v4*
3466 i[34567]86-*-sysv4.2*
3469 i[34567]86-*-unixware2*
3470 i[34567]86-*-unixware*
3479 * Other removed features
3486 Various m68k-only ROM monitors.
3493 Various Renesas ROM monitors and debugging interfaces for SH and
3498 Support for a Macraigor serial interface to on-chip debugging.
3499 GDB does not directly support the newer parallel or USB
3504 A debug information format. The predecessor to DWARF 2 and
3505 DWARF 3, which are still supported.
3507 Support for the HP aCC compiler on HP-UX/PA-RISC
3509 SOM-encapsulated symbolic debugging information, automatic
3510 invocation of pxdb, and the aCC custom C++ ABI. This does not
3511 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3512 with aCC can still be debugged on an assembly level.
3514 MIPS ".pdr" sections
3516 A MIPS-specific format used to describe stack frame layout
3517 in debugging information.
3521 GDB could work with an older version of Guile to debug
3522 the interpreter and Scheme programs running in it.
3524 set mips stack-arg-size
3525 set mips saved-gpreg-size
3527 Use "set mips abi" to control parameter passing for MIPS.
3529 *** Changes in GDB 6.6
3534 Cell Broadband Engine SPU spu-elf
3536 * GDB can now be configured as a cross-debugger targeting native Windows
3537 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3538 running on a Windows system over TCP/IP to debug Windows programs.
3540 * The GDB remote stub, gdbserver, has been updated to support Windows and
3541 Cygwin debugging. Both single-threaded and multi-threaded programs are
3544 * The "set trust-readonly-sections" command works again. This command was
3545 broken in GDB 6.3, 6.4, and 6.5.
3547 * The "load" command now supports writing to flash memory, if the remote
3548 stub provides the required support.
3550 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3551 longer requires symbolic debug information (e.g. DWARF-2).
3556 unset substitute-path
3557 show substitute-path
3558 Manage a list of substitution rules that GDB uses to rewrite the name
3559 of the directories where the sources are located. This can be useful
3560 for instance when the sources were moved to a different location
3561 between compilation and debugging.
3565 Print each CLI command as it is executed. Each command is prefixed with
3566 a number of `+' symbols representing the nesting depth.
3567 The source command now has a `-v' option to enable the same feature.
3571 The ARM Demon monitor support (RDP protocol, "target rdp").
3573 Kernel Object Display, an embedded debugging feature which only worked with
3574 an obsolete version of Cisco IOS.
3576 The 'set download-write-size' and 'show download-write-size' commands.
3578 * New remote packets
3581 Tell a stub about GDB client features, and request remote target features.
3582 The first feature implemented is PacketSize, which allows the target to
3583 specify the size of packets it can handle - to minimize the number of
3584 packets required and improve performance when connected to a remote
3588 Fetch an OS auxilliary vector from the remote stub. This packet is a
3589 more efficient replacement for qPart:auxv:read.
3591 qXfer:memory-map:read:
3592 Fetch a memory map from the remote stub, including information about
3593 RAM, ROM, and flash memory devices.
3598 Erase and program a flash memory device.
3600 * Removed remote packets
3603 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3604 used it, and only gdbserver implemented it.
3606 *** Changes in GDB 6.5
3610 Renesas M32C/M16C m32c-elf
3612 Morpho Technologies ms1 ms1-elf
3616 init-if-undefined Initialize a convenience variable, but
3617 only if it doesn't already have a value.
3619 The following commands are presently only implemented for native GNU/Linux:
3621 checkpoint Save a snapshot of the program state.
3623 restart <n> Return the program state to a
3624 previously saved state.
3626 info checkpoints List currently saved checkpoints.
3628 delete-checkpoint <n> Delete a previously saved checkpoint.
3630 set|show detach-on-fork Tell gdb whether to detach from a newly
3631 forked process, or to keep debugging it.
3633 info forks List forks of the user program that
3634 are available to be debugged.
3636 fork <n> Switch to debugging one of several
3637 forks of the user program that are
3638 available to be debugged.
3640 delete-fork <n> Delete a fork from the list of forks
3641 that are available to be debugged (and
3642 kill the forked process).
3644 detach-fork <n> Delete a fork from the list of forks
3645 that are available to be debugged (and
3646 allow the process to continue).
3650 Morpho Technologies ms2 ms1-elf
3652 * Improved Windows host support
3654 GDB now builds as a cross debugger hosted on i686-mingw32, including
3655 native console support, and remote communications using either
3656 network sockets or serial ports.
3658 * Improved Modula-2 language support
3660 GDB can now print most types in the Modula-2 syntax. This includes:
3661 basic types, set types, record types, enumerated types, range types,
3662 pointer types and ARRAY types. Procedure var parameters are correctly
3663 printed and hexadecimal addresses and character constants are also
3664 written in the Modula-2 syntax. Best results can be obtained by using
3665 GNU Modula-2 together with the -gdwarf-2 command line option.
3669 The ARM rdi-share module.
3671 The Netware NLM debug server.
3673 *** Changes in GDB 6.4
3675 * New native configurations
3677 OpenBSD/arm arm*-*-openbsd*
3678 OpenBSD/mips64 mips64-*-openbsd*
3682 Morpho Technologies ms1 ms1-elf
3684 * New command line options
3686 --batch-silent As for --batch, but totally silent.
3687 --return-child-result The debugger will exist with the same value
3688 the child (debugged) program exited with.
3689 --eval-command COMMAND, -ex COMMAND
3690 Execute a single GDB CLI command. This may be
3691 specified multiple times and in conjunction
3692 with the --command (-x) option.
3694 * Deprecated commands removed
3696 The following commands, that were deprecated in 2000, have been
3700 set|show arm disassembly-flavor set|show arm disassembler
3701 othernames set arm disassembler
3702 set|show remotedebug set|show debug remote
3703 set|show archdebug set|show debug arch
3704 set|show eventdebug set|show debug event
3707 * New BSD user-level threads support
3709 It is now possible to debug programs using the user-level threads
3710 library on OpenBSD and FreeBSD. Currently supported (target)
3713 FreeBSD/amd64 x86_64-*-freebsd*
3714 FreeBSD/i386 i386-*-freebsd*
3715 OpenBSD/i386 i386-*-openbsd*
3717 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3718 are not yet supported.
3720 * New support for Matsushita MN10300 w/sim added
3721 (Work in progress). mn10300-elf.
3723 * REMOVED configurations and files
3725 VxWorks and the XDR protocol *-*-vxworks
3726 Motorola MCORE mcore-*-*
3727 National Semiconductor NS32000 ns32k-*-*
3729 * New "set print array-indexes" command
3731 After turning this setting "on", GDB prints the index of each element
3732 when displaying arrays. The default is "off" to preserve the previous
3735 * VAX floating point support
3737 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3739 * User-defined command support
3741 In addition to using $arg0..$arg9 for argument passing, it is now possible
3742 to use $argc to determine now many arguments have been passed. See the
3743 section on user-defined commands in the user manual for more information.
3745 *** Changes in GDB 6.3:
3747 * New command line option
3749 GDB now accepts -l followed by a number to set the timeout for remote
3752 * GDB works with GCC -feliminate-dwarf2-dups
3754 GDB now supports a more compact representation of DWARF-2 debug
3755 information using DW_FORM_ref_addr references. These are produced
3756 by GCC with the option -feliminate-dwarf2-dups and also by some
3757 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3758 to use -feliminate-dwarf2-dups.
3760 * Internationalization
3762 When supported by the host system, GDB will be built with
3763 internationalization (libintl). The task of marking up the sources is
3764 continued, we're looking forward to our first translation.
3768 Initial support for debugging programs compiled with the GNAT
3769 implementation of the Ada programming language has been integrated
3770 into GDB. In this release, support is limited to expression evaluation.
3772 * New native configurations
3774 GNU/Linux/m32r m32r-*-linux-gnu
3778 GDB's remote protocol now includes support for the 'p' packet. This
3779 packet is used to fetch individual registers from a remote inferior.
3781 * END-OF-LIFE registers[] compatibility module
3783 GDB's internal register infrastructure has been completely rewritten.
3784 The new infrastructure making possible the implementation of key new
3785 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3788 GDB 6.3 will be the last release to include the the registers[]
3789 compatibility module that allowed out-of-date configurations to
3790 continue to work. This change directly impacts the following
3800 powerpc bdm protocol
3802 Unless there is activity to revive these configurations, they will be
3803 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3805 * OBSOLETE configurations and files
3807 Configurations that have been declared obsolete in this release have
3808 been commented out. Unless there is activity to revive these
3809 configurations, the next release of GDB will have their sources
3810 permanently REMOVED.
3819 *** Changes in GDB 6.2.1:
3821 * MIPS `break main; run' gave an heuristic-fence-post warning
3823 When attempting to run even a simple program, a warning about
3824 heuristic-fence-post being hit would be reported. This problem has
3827 * MIPS IRIX 'long double' crashed GDB
3829 When examining a long double variable, GDB would get a segmentation
3830 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3831 IRIX long double values).
3835 A bug in the VAX stack code was causing problems with the "next"
3836 command. This problem has been fixed.
3838 *** Changes in GDB 6.2:
3840 * Fix for ``many threads''
3842 On GNU/Linux systems that use the NPTL threads library, a program
3843 rapidly creating and deleting threads would confuse GDB leading to the
3846 ptrace: No such process.
3847 thread_db_get_info: cannot get thread info: generic error
3849 This problem has been fixed.
3851 * "-async" and "-noasync" options removed.
3853 Support for the broken "-noasync" option has been removed (it caused
3856 * New ``start'' command.
3858 This command runs the program until the begining of the main procedure.
3860 * New BSD Kernel Data Access Library (libkvm) interface
3862 Using ``target kvm'' it is now possible to debug kernel core dumps and
3863 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3864 platforms. Currently supported (native-only) configurations are:
3866 FreeBSD/amd64 x86_64-*-freebsd*
3867 FreeBSD/i386 i?86-*-freebsd*
3868 NetBSD/i386 i?86-*-netbsd*
3869 NetBSD/m68k m68*-*-netbsd*
3870 NetBSD/sparc sparc-*-netbsd*
3871 OpenBSD/amd64 x86_64-*-openbsd*
3872 OpenBSD/i386 i?86-*-openbsd*
3873 OpenBSD/m68k m68*-openbsd*
3874 OpenBSD/sparc sparc-*-openbsd*
3876 * Signal trampoline code overhauled
3878 Many generic problems with GDB's signal handling code have been fixed.
3879 These include: backtraces through non-contiguous stacks; recognition
3880 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3881 call; backtrace through a signal trampoline; step into and out of
3882 signal handlers; and single-stepping in the signal trampoline.
3884 Please note that kernel bugs are a limiting factor here. These
3885 features have been shown to work on an s390 GNU/Linux system that
3886 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3888 * Cygwin support for DWARF 2 added.
3890 * New native configurations
3892 GNU/Linux/hppa hppa*-*-linux*
3893 OpenBSD/hppa hppa*-*-openbsd*
3894 OpenBSD/m68k m68*-*-openbsd*
3895 OpenBSD/m88k m88*-*-openbsd*
3896 OpenBSD/powerpc powerpc-*-openbsd*
3897 NetBSD/vax vax-*-netbsd*
3898 OpenBSD/vax vax-*-openbsd*
3900 * END-OF-LIFE frame compatibility module
3902 GDB's internal frame infrastructure has been completely rewritten.
3903 The new infrastructure making it possible to support key new features
3904 including DWARF 2 Call Frame Information. To aid in the task of
3905 migrating old configurations to this new infrastructure, a
3906 compatibility module, that allowed old configurations to continue to
3907 work, was also included.
3909 GDB 6.2 will be the last release to include this frame compatibility
3910 module. This change directly impacts the following configurations:
3920 Unless there is activity to revive these configurations, they will be
3921 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3923 * REMOVED configurations and files
3925 Sun 3, running SunOS 3 m68*-*-sunos3*
3926 Sun 3, running SunOS 4 m68*-*-sunos4*
3927 Sun 2, running SunOS 3 m68000-*-sunos3*
3928 Sun 2, running SunOS 4 m68000-*-sunos4*
3929 Motorola 680x0 running LynxOS m68*-*-lynxos*
3930 AT&T 3b1/Unix pc m68*-att-*
3931 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3932 decstation mips-dec-* mips-little-*
3933 riscos mips-*-riscos* mips-*-sysv*
3934 sonymips mips-sony-*
3935 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3937 *** Changes in GDB 6.1.1:
3939 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3941 The TUI (Text-mode User Interface) is now built as part of a default
3942 GDB configuration. It is enabled by either selecting the TUI with the
3943 command line option "-i=tui" or by running the separate "gdbtui"
3944 program. For more information on the TUI, see the manual "Debugging
3947 * Pending breakpoint support (also included in GDB 6.1)
3949 Support has been added to allow you to specify breakpoints in shared
3950 libraries that have not yet been loaded. If a breakpoint location
3951 cannot be found, and the "breakpoint pending" option is set to auto,
3952 GDB queries you if you wish to make the breakpoint pending on a future
3953 shared-library load. If and when GDB resolves the breakpoint symbol,
3954 the pending breakpoint is removed as one or more regular breakpoints
3957 Pending breakpoints are very useful for GCJ Java debugging.
3959 * Fixed ISO-C build problems
3961 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3962 non ISO-C code that stopped them being built using a more strict ISO-C
3963 compiler (e.g., IBM's C compiler).
3965 * Fixed build problem on IRIX 5
3967 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3968 wasn't able to compile compile on an IRIX 5 system.
3970 * Added execute permission to gdb/gdbserver/configure
3972 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3973 permission. This bug would cause configure to fail on a number of
3974 systems (Solaris, IRIX). Ref: server/519.
3976 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3978 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3979 has been updated to use constant array sizes.
3981 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3983 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3984 its generated DWARF Call Frame Info. This encoding was causing GDB to
3985 panic, that panic has been fixed. Ref: gdb/1628.
3987 * Fixed a problem when examining parameters in shared library code.
3989 When examining parameters in optimized shared library code generated
3990 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3991 not available''. GDB now correctly displays the variable's value.
3993 *** Changes in GDB 6.1:
3995 * Removed --with-mmalloc
3997 Support for the mmalloc memory manager has been removed, as it
3998 conflicted with the internal gdb byte cache.
4000 * Changes in AMD64 configurations
4002 The AMD64 target now includes the %cs and %ss registers. As a result
4003 the AMD64 remote protocol has changed; this affects the floating-point
4004 and SSE registers. If you rely on those registers for your debugging,
4005 you should upgrade gdbserver on the remote side.
4007 * Revised SPARC target
4009 The SPARC target has been completely revised, incorporating the
4010 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4011 support for LynxOS and SunOS 4 has been dropped. Calling functions
4012 from within GDB on operating systems with a non-executable stack
4013 (Solaris, OpenBSD) now works.
4017 GDB has a new C++ demangler which does a better job on the mangled
4018 names generated by current versions of g++. It also runs faster, so
4019 with this and other changes gdb should now start faster on large C++
4022 * DWARF 2 Location Expressions
4024 GDB support for location expressions has been extended to support function
4025 arguments and frame bases. Older versions of GDB could crash when they
4028 * C++ nested types and namespaces
4030 GDB's support for nested types and namespaces in C++ has been
4031 improved, especially if you use the DWARF 2 debugging format. (This
4032 is the default for recent versions of GCC on most platforms.)
4033 Specifically, if you have a class "Inner" defined within a class or
4034 namespace "Outer", then GDB realizes that the class's name is
4035 "Outer::Inner", not simply "Inner". This should greatly reduce the
4036 frequency of complaints about not finding RTTI symbols. In addition,
4037 if you are stopped at inside of a function defined within a namespace,
4038 GDB modifies its name lookup accordingly.
4040 * New native configurations
4042 NetBSD/amd64 x86_64-*-netbsd*
4043 OpenBSD/amd64 x86_64-*-openbsd*
4044 OpenBSD/alpha alpha*-*-openbsd*
4045 OpenBSD/sparc sparc-*-openbsd*
4046 OpenBSD/sparc64 sparc64-*-openbsd*
4048 * New debugging protocols
4050 M32R with SDI protocol m32r-*-elf*
4052 * "set prompt-escape-char" command deleted.
4054 The command "set prompt-escape-char" has been deleted. This command,
4055 and its very obscure effet on GDB's prompt, was never documented,
4056 tested, nor mentioned in the NEWS file.
4058 * OBSOLETE configurations and files
4060 Configurations that have been declared obsolete in this release have
4061 been commented out. Unless there is activity to revive these
4062 configurations, the next release of GDB will have their sources
4063 permanently REMOVED.
4065 Sun 3, running SunOS 3 m68*-*-sunos3*
4066 Sun 3, running SunOS 4 m68*-*-sunos4*
4067 Sun 2, running SunOS 3 m68000-*-sunos3*
4068 Sun 2, running SunOS 4 m68000-*-sunos4*
4069 Motorola 680x0 running LynxOS m68*-*-lynxos*
4070 AT&T 3b1/Unix pc m68*-att-*
4071 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4072 decstation mips-dec-* mips-little-*
4073 riscos mips-*-riscos* mips-*-sysv*
4074 sonymips mips-sony-*
4075 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4077 * REMOVED configurations and files
4079 SGI Irix-4.x mips-sgi-irix4 or iris4
4080 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4081 Z8000 simulator z8k-zilog-none or z8ksim
4082 Matsushita MN10200 w/simulator mn10200-*-*
4083 H8/500 simulator h8500-hitachi-hms or h8500hms
4084 HP/PA running BSD hppa*-*-bsd*
4085 HP/PA running OSF/1 hppa*-*-osf*
4086 HP/PA Pro target hppa*-*-pro*
4087 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4088 386BSD i[3456]86-*-bsd*
4089 Sequent family i[3456]86-sequent-sysv4*
4090 i[3456]86-sequent-sysv*
4091 i[3456]86-sequent-bsd*
4092 SPARC running LynxOS sparc-*-lynxos*
4093 SPARC running SunOS 4 sparc-*-sunos4*
4094 Tsqware Sparclet sparclet-*-*
4095 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4097 *** Changes in GDB 6.0:
4101 Support for debugging the Objective-C programming language has been
4102 integrated into GDB.
4104 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4106 DWARF 2's Call Frame Information makes available compiler generated
4107 information that more exactly describes the program's run-time stack.
4108 By using this information, GDB is able to provide more robust stack
4111 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4112 have been updated to use a new backtrace mechanism which includes
4113 DWARF 2 CFI support.
4117 GDB's remote protocol has been extended to include support for hosted
4118 file I/O (where the remote target uses GDB's file system). See GDB's
4119 remote protocol documentation for details.
4121 * All targets using the new architecture framework.
4123 All of GDB's targets have been updated to use the new internal
4124 architecture framework. The way is now open for future GDB releases
4125 to include cross-architecture native debugging support (i386 on amd64,
4128 * GNU/Linux's Thread Local Storage (TLS)
4130 GDB now includes support for for the GNU/Linux implementation of
4131 per-thread variables.
4133 * GNU/Linux's Native POSIX Thread Library (NPTL)
4135 GDB's thread code has been updated to work with either the new
4136 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4138 * Separate debug info.
4140 GDB, in conjunction with BINUTILS, now supports a mechanism for
4141 automatically loading debug information from a separate file. Instead
4142 of shipping full debug and non-debug versions of system libraries,
4143 system integrators can now instead ship just the stripped libraries
4144 and optional debug files.
4146 * DWARF 2 Location Expressions
4148 DWARF 2 Location Expressions allow the compiler to more completely
4149 describe the location of variables (even in optimized code) to the
4152 GDB now includes preliminary support for location expressions (support
4153 for DW_OP_piece is still missing).
4157 A number of long standing bugs that caused GDB to die while starting a
4158 Java application have been fixed. GDB's Java support is now
4159 considered "useable".
4161 * GNU/Linux support for fork, vfork, and exec.
4163 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4164 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4167 * GDB supports logging output to a file
4169 There are two new commands, "set logging" and "show logging", which can be
4170 used to capture GDB's output to a file.
4172 * The meaning of "detach" has changed for gdbserver
4174 The "detach" command will now resume the application, as documented. To
4175 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4178 * d10v, m68hc11 `regs' command deprecated
4180 The `info registers' command has been updated so that it displays the
4181 registers using a format identical to the old `regs' command.
4185 A new command, "maint set profile on/off", has been added. This command can
4186 be used to enable or disable profiling while running GDB, to profile a
4187 session or a set of commands. In addition there is a new configure switch,
4188 "--enable-profiling", which will cause GDB to be compiled with profiling
4189 data, for more informative profiling results.
4191 * Default MI syntax changed to "mi2".
4193 The default MI (machine interface) syntax, enabled by the command line
4194 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4195 "mi1", can be enabled by specifying the option "-i=mi1".
4197 Support for the original "mi0" syntax (included in GDB 5.0) has been
4200 Fix for gdb/192: removed extraneous space when displaying frame level.
4201 Fix for gdb/672: update changelist is now output in mi list format.
4202 Fix for gdb/702: a -var-assign that updates the value now shows up
4203 in a subsequent -var-update.
4205 * New native configurations.
4207 FreeBSD/amd64 x86_64-*-freebsd*
4209 * Multi-arched targets.
4211 HP/PA HPUX11 hppa*-*-hpux*
4212 Renesas M32R/D w/simulator m32r-*-elf*
4214 * OBSOLETE configurations and files
4216 Configurations that have been declared obsolete in this release have
4217 been commented out. Unless there is activity to revive these
4218 configurations, the next release of GDB will have their sources
4219 permanently REMOVED.
4221 Z8000 simulator z8k-zilog-none or z8ksim
4222 Matsushita MN10200 w/simulator mn10200-*-*
4223 H8/500 simulator h8500-hitachi-hms or h8500hms
4224 HP/PA running BSD hppa*-*-bsd*
4225 HP/PA running OSF/1 hppa*-*-osf*
4226 HP/PA Pro target hppa*-*-pro*
4227 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4228 Sequent family i[3456]86-sequent-sysv4*
4229 i[3456]86-sequent-sysv*
4230 i[3456]86-sequent-bsd*
4231 Tsqware Sparclet sparclet-*-*
4232 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4234 * REMOVED configurations and files
4237 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4238 IBM AIX PS/2 i[3456]86-*-aix
4239 i386 running Mach 3.0 i[3456]86-*-mach3*
4240 i386 running Mach i[3456]86-*-mach*
4241 i386 running OSF/1 i[3456]86-*osf1mk*
4242 HP/Apollo 68k Family m68*-apollo*-sysv*,
4244 m68*-hp-bsd*, m68*-hp-hpux*
4245 Argonaut Risc Chip (ARC) arc-*-*
4246 Mitsubishi D30V d30v-*-*
4247 Fujitsu FR30 fr30-*-elf*
4248 OS/9000 i[34]86-*-os9k
4249 I960 with MON960 i960-*-coff
4251 * MIPS $fp behavior changed
4253 The convenience variable $fp, for the MIPS, now consistently returns
4254 the address of the current frame's base. Previously, depending on the
4255 context, $fp could refer to either $sp or the current frame's base
4256 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4257 The GNU Source-Level Debugger''.
4259 *** Changes in GDB 5.3:
4261 * GNU/Linux shared library multi-threaded performance improved.
4263 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4264 `/proc', in preference to `ptrace' for memory reads. This may result
4265 in an improvement in the start-up time of multi-threaded, shared
4266 library applications when run under GDB. One GDB user writes: ``loads
4267 shared libs like mad''.
4269 * ``gdbserver'' now supports multi-threaded applications on some targets
4271 Support for debugging multi-threaded applications which use
4272 the GNU/Linux LinuxThreads package has been added for
4273 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4274 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4276 * GDB now supports C/C++ preprocessor macros.
4278 GDB now expands preprocessor macro invocations in C/C++ expressions,
4279 and provides various commands for showing macro definitions and how
4282 The new command `macro expand EXPRESSION' expands any macro
4283 invocations in expression, and shows the result.
4285 The new command `show macro MACRO-NAME' shows the definition of the
4286 macro named MACRO-NAME, and where it was defined.
4288 Most compilers don't include information about macros in the debugging
4289 information by default. In GCC 3.1, for example, you need to compile
4290 your program with the options `-gdwarf-2 -g3'. If the macro
4291 information is present in the executable, GDB will read it.
4293 * Multi-arched targets.
4295 DEC Alpha (partial) alpha*-*-*
4296 DEC VAX (partial) vax-*-*
4298 National Semiconductor NS32000 (partial) ns32k-*-*
4299 Motorola 68000 (partial) m68k-*-*
4300 Motorola MCORE mcore-*-*
4304 Fujitsu FRV architecture added by Red Hat frv*-*-*
4307 * New native configurations
4309 Alpha NetBSD alpha*-*-netbsd*
4310 SH NetBSD sh*-*-netbsdelf*
4311 MIPS NetBSD mips*-*-netbsd*
4312 UltraSPARC NetBSD sparc64-*-netbsd*
4314 * OBSOLETE configurations and files
4316 Configurations that have been declared obsolete in this release have
4317 been commented out. Unless there is activity to revive these
4318 configurations, the next release of GDB will have their sources
4319 permanently REMOVED.
4321 Mitsubishi D30V d30v-*-*
4322 OS/9000 i[34]86-*-os9k
4323 IBM AIX PS/2 i[3456]86-*-aix
4324 Fujitsu FR30 fr30-*-elf*
4325 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4326 Argonaut Risc Chip (ARC) arc-*-*
4327 i386 running Mach 3.0 i[3456]86-*-mach3*
4328 i386 running Mach i[3456]86-*-mach*
4329 i386 running OSF/1 i[3456]86-*osf1mk*
4330 HP/Apollo 68k Family m68*-apollo*-sysv*,
4332 m68*-hp-bsd*, m68*-hp-hpux*
4333 I960 with MON960 i960-*-coff
4335 * OBSOLETE languages
4337 CHILL, a Pascal like language used by telecommunications companies.
4339 * REMOVED configurations and files
4341 AMD 29k family via UDI a29k-amd-udi, udi29k
4342 A29K VxWorks a29k-*-vxworks
4343 AMD 29000 embedded, using EBMON a29k-none-none
4344 AMD 29000 embedded with COFF a29k-none-coff
4345 AMD 29000 embedded with a.out a29k-none-aout
4347 testsuite/gdb.hp/gdb.threads-hp/ directory
4349 * New command "set max-user-call-depth <nnn>"
4351 This command allows the user to limit the call depth of user-defined
4352 commands. The default is 1024.
4354 * Changes in FreeBSD/i386 native debugging.
4356 Support for the "generate-core-file" has been added.
4358 * New commands "dump", "append", and "restore".
4360 These commands allow data to be copied from target memory
4361 to a bfd-format or binary file (dump and append), and back
4362 from a file into memory (restore).
4364 * Improved "next/step" support on multi-processor Alpha Tru64.
4366 The previous single-step mechanism could cause unpredictable problems,
4367 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4368 of a software single-step mechanism prevents this.
4370 *** Changes in GDB 5.2.1:
4378 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4379 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4380 Fix, by Joel Brobecker imported from mainline.
4382 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4383 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4384 Fix, by Fred Fish, imported from mainline.
4386 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4387 Surprisingly enough, it works now.
4388 By Michal Ludvig, imported from mainline.
4390 i386 hardware watchpoint support:
4391 avoid misses on second run for some targets.
4392 By Pierre Muller, imported from mainline.
4394 *** Changes in GDB 5.2:
4396 * New command "set trust-readonly-sections on[off]".
4398 This command is a hint that tells gdb that read-only sections
4399 really are read-only (ie. that their contents will not change).
4400 In this mode, gdb will go to the object file rather than the
4401 target to read memory from read-only sections (such as ".text").
4402 This can be a significant performance improvement on some
4403 (notably embedded) targets.
4405 * New command "generate-core-file" (or "gcore").
4407 This new gdb command allows the user to drop a core file of the child
4408 process state at any time. So far it's been implemented only for
4409 GNU/Linux and Solaris, but should be relatively easily ported to other
4410 hosts. Argument is core file name (defaults to core.<pid>).
4412 * New command line option
4414 GDB now accepts --pid or -p followed by a process id.
4416 * Change in command line behavior -- corefiles vs. process ids.
4418 There is a subtle behavior in the way in which GDB handles
4419 command line arguments. The first non-flag argument is always
4420 a program to debug, but the second non-flag argument may either
4421 be a corefile or a process id. Previously, GDB would attempt to
4422 open the second argument as a corefile, and if that failed, would
4423 issue a superfluous error message and then attempt to attach it as
4424 a process. Now, if the second argument begins with a non-digit,
4425 it will be treated as a corefile. If it begins with a digit,
4426 GDB will attempt to attach it as a process, and if no such process
4427 is found, will then attempt to open it as a corefile.
4429 * Changes in ARM configurations.
4431 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4432 configuration is fully multi-arch.
4434 * New native configurations
4436 ARM NetBSD arm*-*-netbsd*
4437 x86 OpenBSD i[3456]86-*-openbsd*
4438 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4439 Sparc64 running FreeBSD sparc64-*-freebsd*
4443 Sanyo XStormy16 xstormy16-elf
4445 * OBSOLETE configurations and files
4447 Configurations that have been declared obsolete in this release have
4448 been commented out. Unless there is activity to revive these
4449 configurations, the next release of GDB will have their sources
4450 permanently REMOVED.
4452 AMD 29k family via UDI a29k-amd-udi, udi29k
4453 A29K VxWorks a29k-*-vxworks
4454 AMD 29000 embedded, using EBMON a29k-none-none
4455 AMD 29000 embedded with COFF a29k-none-coff
4456 AMD 29000 embedded with a.out a29k-none-aout
4458 testsuite/gdb.hp/gdb.threads-hp/ directory
4460 * REMOVED configurations and files
4462 TI TMS320C80 tic80-*-*
4464 PowerPC Solaris powerpcle-*-solaris*
4465 PowerPC Windows NT powerpcle-*-cygwin32
4466 PowerPC Netware powerpc-*-netware*
4467 Harris/CXUX m88k m88*-harris-cxux*
4468 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4469 ns32k-utek-sysv* ns32k-utek-*
4470 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4471 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4472 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4473 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4474 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4476 * Changes to command line processing
4478 The new `--args' feature can be used to specify command-line arguments
4479 for the inferior from gdb's command line.
4481 * Changes to key bindings
4483 There is a new `operate-and-get-next' function bound to `C-o'.
4485 *** Changes in GDB 5.1.1
4487 Fix compile problem on DJGPP.
4489 Fix a problem with floating-point registers on the i386 being
4492 Fix to stop GDB crashing on .debug_str debug info.
4494 Numerous documentation fixes.
4496 Numerous testsuite fixes.
4498 *** Changes in GDB 5.1:
4500 * New native configurations
4502 Alpha FreeBSD alpha*-*-freebsd*
4503 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4504 MIPS GNU/Linux mips*-*-linux*
4505 MIPS SGI Irix 6.x mips*-sgi-irix6*
4506 ia64 AIX ia64-*-aix*
4507 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4511 Motorola 68HC11 and 68HC12 m68hc11-elf
4513 UltraSparc running GNU/Linux sparc64-*-linux*
4515 * OBSOLETE configurations and files
4517 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4518 Harris/CXUX m88k m88*-harris-cxux*
4519 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4520 ns32k-utek-sysv* ns32k-utek-*
4521 TI TMS320C80 tic80-*-*
4523 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4524 PowerPC Solaris powerpcle-*-solaris*
4525 PowerPC Windows NT powerpcle-*-cygwin32
4526 PowerPC Netware powerpc-*-netware*
4527 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4528 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4529 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4530 Apple Macintosh (MPW) host N/A
4532 stuff.c (Program to stuff files into a specially prepared space in kdb)
4533 kdb-start.c (Main loop for the standalone kernel debugger)
4535 Configurations that have been declared obsolete in this release have
4536 been commented out. Unless there is activity to revive these
4537 configurations, the next release of GDB will have their sources
4538 permanently REMOVED.
4540 * REMOVED configurations and files
4542 Altos 3068 m68*-altos-*
4543 Convex c1-*-*, c2-*-*
4545 ARM RISCix arm-*-* (as host)
4549 * GDB has been converted to ISO C.
4551 GDB's source code has been converted to ISO C. In particular, the
4552 sources are fully protoized, and rely on standard headers being
4557 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4559 * The MI enabled by default.
4561 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4562 revised and enabled by default. Packages which use GDB as a debugging
4563 engine behind a UI or another front end are encouraged to switch to
4564 using the GDB/MI interface, instead of the old annotations interface
4565 which is now deprecated.
4567 * Support for debugging Pascal programs.
4569 GDB now includes support for debugging Pascal programs. The following
4570 main features are supported:
4572 - Pascal-specific data types such as sets;
4574 - automatic recognition of Pascal sources based on file-name
4577 - Pascal-style display of data types, variables, and functions;
4579 - a Pascal expression parser.
4581 However, some important features are not yet supported.
4583 - Pascal string operations are not supported at all;
4585 - there are some problems with boolean types;
4587 - Pascal type hexadecimal constants are not supported
4588 because they conflict with the internal variables format;
4590 - support for Pascal objects and classes is not full yet;
4592 - unlike Pascal, GDB is case-sensitive for symbol names.
4594 * Changes in completion.
4596 Commands such as `shell', `run' and `set args', which pass arguments
4597 to inferior programs, now complete on file names, similar to what
4598 users expect at the shell prompt.
4600 Commands which accept locations, such as `disassemble', `print',
4601 `breakpoint', `until', etc. now complete on filenames as well as
4602 program symbols. Thus, if you type "break foob TAB", and the source
4603 files linked into the programs include `foobar.c', that file name will
4604 be one of the candidates for completion. However, file names are not
4605 considered for completion after you typed a colon that delimits a file
4606 name from a name of a function in that file, as in "break foo.c:bar".
4608 `set demangle-style' completes on available demangling styles.
4610 * New platform-independent commands:
4612 It is now possible to define a post-hook for a command as well as a
4613 hook that runs before the command. For more details, see the
4614 documentation of `hookpost' in the GDB manual.
4616 * Changes in GNU/Linux native debugging.
4618 Support for debugging multi-threaded programs has been completely
4619 revised for all platforms except m68k and sparc. You can now debug as
4620 many threads as your system allows you to have.
4622 Attach/detach is supported for multi-threaded programs.
4624 Support for SSE registers was added for x86. This doesn't work for
4625 multi-threaded programs though.
4627 * Changes in MIPS configurations.
4629 Multi-arch support is enabled for all MIPS configurations.
4631 GDB can now be built as native debugger on SGI Irix 6.x systems for
4632 debugging n32 executables. (Debugging 64-bit executables is not yet
4635 * Unified support for hardware watchpoints in all x86 configurations.
4637 Most (if not all) native x86 configurations support hardware-assisted
4638 breakpoints and watchpoints in a unified manner. This support
4639 implements debug register sharing between watchpoints, which allows to
4640 put a virtually infinite number of watchpoints on the same address,
4641 and also supports watching regions up to 16 bytes with several debug
4644 The new maintenance command `maintenance show-debug-regs' toggles
4645 debugging print-outs in functions that insert, remove, and test
4646 watchpoints and hardware breakpoints.
4648 * Changes in the DJGPP native configuration.
4650 New command ``info dos sysinfo'' displays assorted information about
4651 the CPU, OS, memory, and DPMI server.
4653 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4654 display information about segment descriptors stored in GDT, LDT, and
4657 New commands ``info dos pde'' and ``info dos pte'' display entries
4658 from Page Directory and Page Tables (for now works with CWSDPMI only).
4659 New command ``info dos address-pte'' displays the Page Table entry for
4660 a given linear address.
4662 GDB can now pass command lines longer than 126 characters to the
4663 program being debugged (requires an update to the libdbg.a library
4664 which is part of the DJGPP development kit).
4666 DWARF2 debug info is now supported.
4668 It is now possible to `step' and `next' through calls to `longjmp'.
4670 * Changes in documentation.
4672 All GDB documentation was converted to GFDL, the GNU Free
4673 Documentation License.
4675 Tracepoints-related commands are now fully documented in the GDB
4678 TUI, the Text-mode User Interface, is now documented in the manual.
4680 Tracepoints-related commands are now fully documented in the GDB
4683 The "GDB Internals" manual now has an index. It also includes
4684 documentation of `ui_out' functions, GDB coding standards, x86
4685 hardware watchpoints, and memory region attributes.
4687 * GDB's version number moved to ``version.in''
4689 The Makefile variable VERSION has been replaced by the file
4690 ``version.in''. People creating GDB distributions should update the
4691 contents of this file.
4695 GUD support is now a standard part of the EMACS distribution.
4697 *** Changes in GDB 5.0:
4699 * Improved support for debugging FP programs on x86 targets
4701 Unified and much-improved support for debugging floating-point
4702 programs on all x86 targets. In particular, ``info float'' now
4703 displays the FP registers in the same format on all x86 targets, with
4704 greater level of detail.
4706 * Improvements and bugfixes in hardware-assisted watchpoints
4708 It is now possible to watch array elements, struct members, and
4709 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4710 on x86 targets no longer erroneously trigger when the address is
4713 * Improvements in the native DJGPP version of GDB
4715 The distribution now includes all the scripts and auxiliary files
4716 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4717 machines ``out of the box''.
4719 The DJGPP version can now debug programs that use signals. It is
4720 possible to catch signals that happened in the debuggee, deliver
4721 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4722 would kill the program being debugged.) Programs that hook hardware
4723 interrupts (keyboard, timer, etc.) can also be debugged.
4725 It is now possible to debug DJGPP programs that redirect their
4726 standard handles or switch them to raw (as opposed to cooked) mode, or
4727 even close them. The command ``run < foo > bar'' works as expected,
4728 and ``info terminal'' reports useful information about the debuggee's
4729 terminal, including raw/cooked mode, redirection, etc.
4731 The DJGPP version now uses termios functions for console I/O, which
4732 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4735 DOS-style file names with drive letters are now fully supported by
4738 It is now possible to debug DJGPP programs that switch their working
4739 directory. It is also possible to rerun the debuggee any number of
4740 times without restarting GDB; thus, you can use the same setup,
4741 breakpoints, etc. for many debugging sessions.
4743 * New native configurations
4745 ARM GNU/Linux arm*-*-linux*
4746 PowerPC GNU/Linux powerpc-*-linux*
4750 Motorola MCore mcore-*-*
4751 x86 VxWorks i[3456]86-*-vxworks*
4752 PowerPC VxWorks powerpc-*-vxworks*
4753 TI TMS320C80 tic80-*-*
4755 * OBSOLETE configurations
4757 Altos 3068 m68*-altos-*
4758 Convex c1-*-*, c2-*-*
4760 ARM RISCix arm-*-* (as host)
4763 Configurations that have been declared obsolete will be commented out,
4764 but the code will be left in place. If there is no activity to revive
4765 these configurations before the next release of GDB, the sources will
4766 be permanently REMOVED.
4768 * Gould support removed
4770 Support for the Gould PowerNode and NP1 has been removed.
4772 * New features for SVR4
4774 On SVR4 native platforms (such as Solaris), if you attach to a process
4775 without first loading a symbol file, GDB will now attempt to locate and
4776 load symbols from the running process's executable file.
4778 * Many C++ enhancements
4780 C++ support has been greatly improved. Overload resolution now works properly
4781 in almost all cases. RTTI support is on the way.
4783 * Remote targets can connect to a sub-program
4785 A popen(3) style serial-device has been added. This device starts a
4786 sub-process (such as a stand-alone simulator) and then communicates
4787 with that. The sub-program to run is specified using the syntax
4788 ``|<program> <args>'' vis:
4790 (gdb) set remotedebug 1
4791 (gdb) target extended-remote |mn10300-elf-sim program-args
4793 * MIPS 64 remote protocol
4795 A long standing bug in the mips64 remote protocol where by GDB
4796 expected certain 32 bit registers (ex SR) to be transfered as 32
4797 instead of 64 bits has been fixed.
4799 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4800 added to provide backward compatibility with older versions of GDB.
4802 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4804 The command ``set remotebinarydownload'' command has been replaced by
4805 ``set remote X-packet''. Other commands in ``set remote'' family
4806 include ``set remote P-packet''.
4808 * Breakpoint commands accept ranges.
4810 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4811 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4812 ``tracepoint passcount'' also accepts a range of tracepoints.
4814 * ``apropos'' command added.
4816 The ``apropos'' command searches through command names and
4817 documentation strings, printing out matches, making it much easier to
4818 try to find a command that does what you are looking for.
4822 A new machine oriented interface (MI) has been added to GDB. This
4823 interface is designed for debug environments running GDB as a separate
4824 process. This is part of the long term libGDB project. See the
4825 "GDB/MI" chapter of the GDB manual for further information. It can be
4826 enabled by configuring with:
4828 .../configure --enable-gdbmi
4830 *** Changes in GDB-4.18:
4832 * New native configurations
4834 HP-UX 10.20 hppa*-*-hpux10.20
4835 HP-UX 11.x hppa*-*-hpux11.0*
4836 M68K GNU/Linux m68*-*-linux*
4840 Fujitsu FR30 fr30-*-elf*
4841 Intel StrongARM strongarm-*-*
4842 Mitsubishi D30V d30v-*-*
4844 * OBSOLETE configurations
4846 Gould PowerNode, NP1 np1-*-*, pn-*-*
4848 Configurations that have been declared obsolete will be commented out,
4849 but the code will be left in place. If there is no activity to revive
4850 these configurations before the next release of GDB, the sources will
4851 be permanently REMOVED.
4855 As a compatibility experiment, GDB's source files buildsym.h and
4856 buildsym.c have been converted to pure standard C, no longer
4857 containing any K&R compatibility code. We believe that all systems in
4858 use today either come with a standard C compiler, or have a GCC port
4859 available. If this is not true, please report the affected
4860 configuration to bug-gdb@gnu.org immediately. See the README file for
4861 information about getting a standard C compiler if you don't have one
4866 GDB now uses readline 2.2.
4868 * set extension-language
4870 You can now control the mapping between filename extensions and source
4871 languages by using the `set extension-language' command. For instance,
4872 you can ask GDB to treat .c files as C++ by saying
4873 set extension-language .c c++
4874 The command `info extensions' lists all of the recognized extensions
4875 and their associated languages.
4877 * Setting processor type for PowerPC and RS/6000
4879 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4880 you can use the `set processor' command to specify what variant of the
4881 PowerPC family you are debugging. The command
4885 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4886 following PowerPC and RS6000 variants:
4888 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4889 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4891 403GC IBM PowerPC 403GC
4892 505 Motorola PowerPC 505
4893 860 Motorola PowerPC 860 or 850
4894 601 Motorola PowerPC 601
4895 602 Motorola PowerPC 602
4896 603 Motorola/IBM PowerPC 603 or 603e
4897 604 Motorola PowerPC 604 or 604e
4898 750 Motorola/IBM PowerPC 750 or 750
4900 At the moment, this command just tells GDB what to name the
4901 special-purpose processor registers. Since almost all the affected
4902 registers are inaccessible to user-level programs, this command is
4903 only useful for remote debugging in its present form.
4907 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4908 more extensive support for HP-UX. Added features include shared
4909 library support, kernel threads and hardware watchpoints for 11.00,
4910 support for HP's ANSI C and C++ compilers, and a compatibility mode
4911 for xdb and dbx commands.
4915 HP's donation includes the new concept of catchpoints, which is a
4916 generalization of the old catch command. On HP-UX, it is now possible
4917 to catch exec, fork, and vfork, as well as library loading.
4919 This means that the existing catch command has changed; its first
4920 argument now specifies the type of catch to be set up. See the
4921 output of "help catch" for a list of catchpoint types.
4923 * Debugging across forks
4925 On HP-UX, you can choose which process to debug when a fork() happens
4930 HP has donated a curses-based terminal user interface (TUI). To get
4931 it, build with --enable-tui. Although this can be enabled for any
4932 configuration, at present it only works for native HP debugging.
4934 * GDB remote protocol additions
4936 A new protocol packet 'X' that writes binary data is now available.
4937 Default behavior is to try 'X', then drop back to 'M' if the stub
4938 fails to respond. The settable variable `remotebinarydownload'
4939 allows explicit control over the use of 'X'.
4941 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4942 full 64-bit address. The command
4944 set remoteaddresssize 32
4946 can be used to revert to the old behaviour. For existing remote stubs
4947 the change should not be noticed, as the additional address information
4950 In order to assist in debugging stubs, you may use the maintenance
4951 command `packet' to send any text string to the stub. For instance,
4953 maint packet heythere
4955 sends the packet "$heythere#<checksum>". Note that it is very easy to
4956 disrupt a debugging session by sending the wrong packet at the wrong
4959 The compare-sections command allows you to compare section data on the
4960 target to what is in the executable file without uploading or
4961 downloading, by comparing CRC checksums.
4963 * Tracing can collect general expressions
4965 You may now collect general expressions at tracepoints. This requires
4966 further additions to the target-side stub; see tracepoint.c and
4967 doc/agentexpr.texi for further details.
4969 * mask-address variable for Mips
4971 For Mips targets, you may control the zeroing of the upper 32 bits of
4972 a 64-bit address by entering `set mask-address on'. This is mainly
4973 of interest to users of embedded R4xxx and R5xxx processors.
4975 * Higher serial baud rates
4977 GDB's serial code now allows you to specify baud rates 57600, 115200,
4978 230400, and 460800 baud. (Note that your host system may not be able
4979 to achieve all of these rates.)
4983 The i960 configuration now includes an initial implementation of a
4984 builtin simulator, contributed by Jim Wilson.
4987 *** Changes in GDB-4.17:
4989 * New native configurations
4991 Alpha GNU/Linux alpha*-*-linux*
4992 Unixware 2.x i[3456]86-unixware2*
4993 Irix 6.x mips*-sgi-irix6*
4994 PowerPC GNU/Linux powerpc-*-linux*
4995 PowerPC Solaris powerpcle-*-solaris*
4996 Sparc GNU/Linux sparc-*-linux*
4997 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5001 Argonaut Risc Chip (ARC) arc-*-*
5002 Hitachi H8/300S h8300*-*-*
5003 Matsushita MN10200 w/simulator mn10200-*-*
5004 Matsushita MN10300 w/simulator mn10300-*-*
5005 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5006 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5007 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5008 Mitsubishi D10V w/simulator d10v-*-*
5009 Mitsubishi M32R/D w/simulator m32r-*-elf*
5010 Tsqware Sparclet sparclet-*-*
5011 NEC V850 w/simulator v850-*-*
5013 * New debugging protocols
5015 ARM with RDI protocol arm*-*-*
5016 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5017 DDB and LSI variants of PMON protocol mips*-*-*
5018 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5019 PowerPC with SDS protocol powerpc{,le}-*-eabi
5020 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5024 All configurations can now understand and use the DWARF 2 debugging
5025 format. The choice is automatic, if the symbol file contains DWARF 2
5030 GDB now includes basic Java language support. This support is
5031 only useful with Java compilers that produce native machine code.
5033 * solib-absolute-prefix and solib-search-path
5035 For SunOS and SVR4 shared libraries, you may now set the prefix for
5036 loading absolute shared library symbol files, and the search path for
5037 locating non-absolute shared library symbol files.
5039 * Live range splitting
5041 GDB can now effectively debug code for which GCC has performed live
5042 range splitting as part of its optimization. See gdb/doc/LRS for
5043 more details on the expected format of the stabs information.
5047 GDB's support for the GNU Hurd, including thread debugging, has been
5048 updated to work with current versions of the Hurd.
5052 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5053 instruction set. ARM GDB automatically detects when Thumb
5054 instructions are in use, and adjusts disassembly and backtracing
5059 GDB's MIPS target configurations now handle the MIP16 16-bit
5064 GDB now includes support for overlays; if an executable has been
5065 linked such that multiple sections are based at the same address, GDB
5066 will decide which section to use for symbolic info. You can choose to
5067 control the decision manually, using overlay commands, or implement
5068 additional target-side support and use "overlay load-target" to bring
5069 in the overlay mapping. Do "help overlay" for more detail.
5073 The command "info symbol <address>" displays information about
5074 the symbol at the specified address.
5078 The standard remote protocol now includes an extension that allows
5079 asynchronous collection and display of trace data. This requires
5080 extensive support in the target-side debugging stub. Tracing mode
5081 includes a new interaction mode in GDB and new commands: see the
5082 file tracepoint.c for more details.
5086 Configurations for embedded MIPS now include a simulator contributed
5087 by Cygnus Solutions. The simulator supports the instruction sets
5088 of most MIPS variants.
5092 Sparc configurations may now include the ERC32 simulator contributed
5093 by the European Space Agency. The simulator is not built into
5094 Sparc targets by default; configure with --enable-sim to include it.
5098 For target configurations that may include multiple variants of a
5099 basic architecture (such as MIPS and SH), you may now set the
5100 architecture explicitly. "set arch" sets, "info arch" lists
5101 the possible architectures.
5103 *** Changes in GDB-4.16:
5105 * New native configurations
5107 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5108 M68K NetBSD m68k-*-netbsd*
5109 PowerPC AIX 4.x powerpc-*-aix*
5110 PowerPC MacOS powerpc-*-macos*
5111 PowerPC Windows NT powerpcle-*-cygwin32
5112 RS/6000 AIX 4.x rs6000-*-aix4*
5116 ARM with RDP protocol arm-*-*
5117 I960 with MON960 i960-*-coff
5118 MIPS VxWorks mips*-*-vxworks*
5119 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5120 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5122 Matra Sparclet sparclet-*-*
5126 The powerpc-eabi configuration now includes the PSIM simulator,
5127 contributed by Andrew Cagney, with assistance from Mike Meissner.
5128 PSIM is a very elaborate model of the PowerPC, including not only
5129 basic instruction set execution, but also details of execution unit
5130 performance and I/O hardware. See sim/ppc/README for more details.
5134 GDB now works with Solaris 2.5.
5136 * Windows 95/NT native
5138 GDB will now work as a native debugger on Windows 95 and Windows NT.
5139 To build it from source, you must use the "gnu-win32" environment,
5140 which uses a DLL to emulate enough of Unix to run the GNU tools.
5141 Further information, binaries, and sources are available at
5142 ftp.cygnus.com, under pub/gnu-win32.
5144 * dont-repeat command
5146 If a user-defined command includes the command `dont-repeat', then the
5147 command will not be repeated if the user just types return. This is
5148 useful if the command is time-consuming to run, so that accidental
5149 extra keystrokes don't run the same command many times.
5151 * Send break instead of ^C
5153 The standard remote protocol now includes an option to send a break
5154 rather than a ^C to the target in order to interrupt it. By default,
5155 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5157 * Remote protocol timeout
5159 The standard remote protocol includes a new variable `remotetimeout'
5160 that allows you to set the number of seconds before GDB gives up trying
5161 to read from the target. The default value is 2.
5163 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5165 By default GDB will automatically keep track of objects as they are
5166 loaded and unloaded by the dynamic linker. By using the command `set
5167 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5168 when shared library events occur, thus allowing you to set breakpoints
5169 in shared libraries which are explicitly loaded by the inferior.
5171 Note this feature does not work on hpux8. On hpux9 you must link
5172 /usr/lib/end.o into your program. This feature should work
5173 automatically on hpux10.
5175 * Irix 5.x hardware watchpoint support
5177 Irix 5 configurations now support the use of hardware watchpoints.
5179 * Mips protocol "SYN garbage limit"
5181 When debugging a Mips target using the `target mips' protocol, you
5182 may set the number of characters that GDB will ignore by setting
5183 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5184 every character. The default value is 1050.
5186 * Recording and replaying remote debug sessions
5188 If you set `remotelogfile' to the name of a file, gdb will write to it
5189 a recording of a remote debug session. This recording may then be
5190 replayed back to gdb using "gdbreplay". See gdbserver/README for
5191 details. This is useful when you have a problem with GDB while doing
5192 remote debugging; you can make a recording of the session and send it
5193 to someone else, who can then recreate the problem.
5195 * Speedups for remote debugging
5197 GDB includes speedups for downloading and stepping MIPS systems using
5198 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5199 and more efficient S-record downloading.
5201 * Memory use reductions and statistics collection
5203 GDB now uses less memory and reports statistics about memory usage.
5204 Try the `maint print statistics' command, for example.
5206 *** Changes in GDB-4.15:
5208 * Psymtabs for XCOFF
5210 The symbol reader for AIX GDB now uses partial symbol tables. This
5211 can greatly improve startup time, especially for large executables.
5213 * Remote targets use caching
5215 Remote targets now use a data cache to speed up communication with the
5216 remote side. The data cache could lead to incorrect results because
5217 it doesn't know about volatile variables, thus making it impossible to
5218 debug targets which use memory mapped I/O devices. `set remotecache
5219 off' turns the the data cache off.
5221 * Remote targets may have threads
5223 The standard remote protocol now includes support for multiple threads
5224 in the target system, using new protocol commands 'H' and 'T'. See
5225 gdb/remote.c for details.
5229 If GDB is configured with `--enable-netrom', then it will include
5230 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5231 acts as though it is a bank of ROM on the target board, but you can
5232 write into it over the network. GDB's support consists only of
5233 support for fast loading into the emulated ROM; to debug, you must use
5234 another protocol, such as standard remote protocol. The usual
5235 sequence is something like
5237 target nrom <netrom-hostname>
5239 target remote <netrom-hostname>:1235
5243 GDB now includes support for the Apple Macintosh, as a host only. It
5244 may be run as either an MPW tool or as a standalone application, and
5245 it can debug through the serial port. All the usual GDB commands are
5246 available, but to the target command, you must supply "serial" as the
5247 device type instead of "/dev/ttyXX". See mpw-README in the main
5248 directory for more information on how to build. The MPW configuration
5249 scripts */mpw-config.in support only a few targets, and only the
5250 mips-idt-ecoff target has been tested.
5254 GDB configuration now uses autoconf. This is not user-visible,
5255 but does simplify configuration and building.
5259 GDB now supports hpux10.
5261 *** Changes in GDB-4.14:
5263 * New native configurations
5265 x86 FreeBSD i[345]86-*-freebsd
5266 x86 NetBSD i[345]86-*-netbsd
5267 NS32k NetBSD ns32k-*-netbsd
5268 Sparc NetBSD sparc-*-netbsd
5272 A29K VxWorks a29k-*-vxworks
5273 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5274 CPU32 EST-300 emulator m68*-*-est*
5275 PowerPC ELF powerpc-*-elf
5278 * Alpha OSF/1 support for procfs
5280 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5281 possible to attach to running processes. As the mounting of the /proc
5282 filesystem is optional on the Alpha, GDB automatically determines
5283 the availability of /proc during startup. This can lead to problems
5284 if /proc is unmounted after GDB has been started.
5286 * Arguments to user-defined commands
5288 User commands may accept up to 10 arguments separated by whitespace.
5289 Arguments are accessed within the user command via $arg0..$arg9. A
5292 print $arg0 + $arg1 + $arg2
5294 To execute the command use:
5297 Defines the command "adder" which prints the sum of its three arguments.
5298 Note the arguments are text substitutions, so they may reference variables,
5299 use complex expressions, or even perform inferior function calls.
5301 * New `if' and `while' commands
5303 This makes it possible to write more sophisticated user-defined
5304 commands. Both commands take a single argument, which is the
5305 expression to evaluate, and must be followed by the commands to
5306 execute, one per line, if the expression is nonzero, the list being
5307 terminated by the word `end'. The `if' command list may include an
5308 `else' word, which causes the following commands to be executed only
5309 if the expression is zero.
5311 * Fortran source language mode
5313 GDB now includes partial support for Fortran 77. It will recognize
5314 Fortran programs and can evaluate a subset of Fortran expressions, but
5315 variables and functions may not be handled correctly. GDB will work
5316 with G77, but does not yet know much about symbols emitted by other
5319 * Better HPUX support
5321 Most debugging facilities now work on dynamic executables for HPPAs
5322 running hpux9 or later. You can attach to running dynamically linked
5323 processes, but by default the dynamic libraries will be read-only, so
5324 for instance you won't be able to put breakpoints in them. To change
5325 that behavior do the following before running the program:
5331 This will cause the libraries to be mapped private and read-write.
5332 To revert to the normal behavior, do this:
5338 You cannot set breakpoints or examine data in the library until after
5339 the library is loaded if the function/data symbols do not have
5342 GDB can now also read debug symbols produced by the HP C compiler on
5343 HPPAs (sorry, no C++, Fortran or 68k support).
5345 * Target byte order now dynamically selectable
5347 You can choose which byte order to use with a target system, via the
5348 commands "set endian big" and "set endian little", and you can see the
5349 current setting by using "show endian". You can also give the command
5350 "set endian auto", in which case GDB will use the byte order
5351 associated with the executable. Currently, only embedded MIPS
5352 configurations support dynamic selection of target byte order.
5354 * New DOS host serial code
5356 This version uses DPMI interrupts to handle buffered I/O, so you
5357 no longer need to run asynctsr when debugging boards connected to
5360 *** Changes in GDB-4.13:
5362 * New "complete" command
5364 This lists all the possible completions for the rest of the line, if it
5365 were to be given as a command itself. This is intended for use by emacs.
5367 * Trailing space optional in prompt
5369 "set prompt" no longer adds a space for you after the prompt you set. This
5370 allows you to set a prompt which ends in a space or one that does not.
5372 * Breakpoint hit counts
5374 "info break" now displays a count of the number of times the breakpoint
5375 has been hit. This is especially useful in conjunction with "ignore"; you
5376 can ignore a large number of breakpoint hits, look at the breakpoint info
5377 to see how many times the breakpoint was hit, then run again, ignoring one
5378 less than that number, and this will get you quickly to the last hit of
5381 * Ability to stop printing at NULL character
5383 "set print null-stop" will cause GDB to stop printing the characters of
5384 an array when the first NULL is encountered. This is useful when large
5385 arrays actually contain only short strings.
5387 * Shared library breakpoints
5389 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5390 breakpoints in shared libraries before the executable is run.
5392 * Hardware watchpoints
5394 There is a new hardware breakpoint for the watch command for sparclite
5395 targets. See gdb/sparclite/hw_breakpoint.note.
5397 Hardware watchpoints are also now supported under GNU/Linux.
5401 Annotations have been added. These are for use with graphical interfaces,
5402 and are still experimental. Currently only gdba.el uses these.
5404 * Improved Irix 5 support
5406 GDB now works properly with Irix 5.2.
5408 * Improved HPPA support
5410 GDB now works properly with the latest GCC and GAS.
5412 * New native configurations
5414 Sequent PTX4 i[34]86-sequent-ptx4
5415 HPPA running OSF/1 hppa*-*-osf*
5416 Atari TT running SVR4 m68*-*-sysv4*
5417 RS/6000 LynxOS rs6000-*-lynxos*
5421 OS/9000 i[34]86-*-os9k
5422 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5425 * Hitachi SH7000 and E7000-PC ICE support
5427 There is now support for communicating with the Hitachi E7000-PC ICE.
5428 This is available automatically when GDB is configured for the SH.
5432 As usual, a variety of small fixes and improvements, both generic
5433 and configuration-specific. See the ChangeLog for more detail.
5435 *** Changes in GDB-4.12:
5437 * Irix 5 is now supported
5441 GDB-4.12 on the HPPA has a number of changes which make it unable
5442 to debug the output from the currently released versions of GCC and
5443 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5444 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5445 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5448 *** Changes in GDB-4.11:
5450 * User visible changes:
5454 The "set remotedebug" option is now consistent between the mips remote
5455 target, remote targets using the gdb-specific protocol, UDI (AMD's
5456 debug protocol for the 29k) and the 88k bug monitor. It is now an
5457 integer specifying a debug level (normally 0 or 1, but 2 means more
5458 debugging info for the mips target).
5460 * DEC Alpha native support
5462 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5463 debug info, but GDB works fairly well with the DEC compiler and should
5464 work with a future GCC release. See the README file for a few
5465 Alpha-specific notes.
5467 * Preliminary thread implementation
5469 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5471 * LynxOS native and target support for 386
5473 This release has been hosted on LynxOS 2.2, and also can be configured
5474 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5477 * Improvements in C++ mangling/demangling.
5479 This release has much better g++ debugging, specifically in name
5480 mangling/demangling, virtual function calls, print virtual table,
5481 call methods, ...etc.
5483 *** Changes in GDB-4.10:
5485 * User visible changes:
5487 Remote debugging using the GDB-specific (`target remote') protocol now
5488 supports the `load' command. This is only useful if you have some
5489 other way of getting the stub to the target system, and you can put it
5490 somewhere in memory where it won't get clobbered by the download.
5492 Filename completion now works.
5494 When run under emacs mode, the "info line" command now causes the
5495 arrow to point to the line specified. Also, "info line" prints
5496 addresses in symbolic form (as well as hex).
5498 All vxworks based targets now support a user settable option, called
5499 vxworks-timeout. This option represents the number of seconds gdb
5500 should wait for responses to rpc's. You might want to use this if
5501 your vxworks target is, perhaps, a slow software simulator or happens
5502 to be on the far side of a thin network line.
5506 This release contains support for using a DEC alpha as a GDB host for
5507 cross debugging. Native alpha debugging is not supported yet.
5510 *** Changes in GDB-4.9:
5514 This is the first GDB release which is accompanied by a matching testsuite.
5515 The testsuite requires installation of dejagnu, which should be available
5516 via ftp from most sites that carry GNU software.
5520 'Cfront' style demangling has had its name changed to 'ARM' style, to
5521 emphasize that it was written from the specifications in the C++ Annotated
5522 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5523 disclaimers, it still generated too much confusion with users attempting to
5524 use gdb with AT&T cfront.
5528 GDB now uses a standard remote interface to a simulator library.
5529 So far, the library contains simulators for the Zilog Z8001/2, the
5530 Hitachi H8/300, H8/500 and Super-H.
5532 * New targets supported
5534 H8/300 simulator h8300-hitachi-hms or h8300hms
5535 H8/500 simulator h8500-hitachi-hms or h8500hms
5536 SH simulator sh-hitachi-hms or sh
5537 Z8000 simulator z8k-zilog-none or z8ksim
5538 IDT MIPS board over serial line mips-idt-ecoff
5540 Cross-debugging to GO32 targets is supported. It requires a custom
5541 version of the i386-stub.c module which is integrated with the
5542 GO32 memory extender.
5544 * New remote protocols
5546 MIPS remote debugging protocol.
5548 * New source languages supported
5550 This version includes preliminary support for Chill, a Pascal like language
5551 used by telecommunications companies. Chill support is also being integrated
5552 into the GNU compiler, but we don't know when it will be publically available.
5555 *** Changes in GDB-4.8:
5557 * HP Precision Architecture supported
5559 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5560 version of this support was available as a set of patches from the
5561 University of Utah. GDB does not support debugging of programs
5562 compiled with the HP compiler, because HP will not document their file
5563 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5564 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5566 Many problems in the preliminary version have been fixed.
5568 * Faster and better demangling
5570 We have improved template demangling and fixed numerous bugs in the GNU style
5571 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5572 character types (wchar_t) are now supported. Demangling of each symbol is now
5573 only done once, and is cached when the symbol table for a file is read in.
5574 This results in a small increase in memory usage for C programs, a moderate
5575 increase in memory usage for C++ programs, and a fantastic speedup in
5578 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5579 from the specifications in the Annotated Reference Manual, which AT&T's
5580 compiler does not actually implement.
5582 * G++ multiple inheritance compiler problem
5584 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5585 inheritance lattices was reworked to properly discover ambiguities. We
5586 recently found an example which causes this new algorithm to fail in a
5587 very subtle way, producing bad debug information for those classes.
5588 The file 'gcc.patch' (in this directory) can be applied to gcc to
5589 circumvent the problem. A future GCC release will contain a complete
5592 The previous G++ debug info problem (mentioned below for the gdb-4.7
5593 release) is fixed in gcc version 2.3.2.
5595 * Improved configure script
5597 The `configure' script will now attempt to guess your system type if
5598 you don't supply a host system type. The old scheme of supplying a
5599 host system triplet is preferable over using this. All the magic is
5600 done in the new `config.guess' script. Examine it for details.
5602 We have also brought our configure script much more in line with the FSF's
5603 version. It now supports the --with-xxx options. In particular,
5604 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5605 The resulting GDB will not be able to read arbitrary object file formats --
5606 only the format ``expected'' to be used on the configured target system.
5607 We hope to make this the default in a future release.
5609 * Documentation improvements
5611 There's new internal documentation on how to modify GDB, and how to
5612 produce clean changes to the code. We implore people to read it
5613 before submitting changes.
5615 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5616 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5617 `info' files are also provided. To build `info' files from scratch,
5618 you will need the latest `makeinfo' release, which will be available in
5619 a future texinfo-X.Y release.
5621 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5622 We're not sure exactly which versions have this problem, but it has
5623 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5624 or better. If that isn't possible, there is a patch in
5625 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5626 around this problem.
5630 GDB now supports array constants that can be used in expressions typed in by
5631 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5632 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5635 The new directory `gdb/sparclite' contains a program that demonstrates
5636 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5638 * New native hosts supported
5640 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5641 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5643 * New targets supported
5645 AMD 29k family via UDI a29k-amd-udi or udi29k
5647 * New file formats supported
5649 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5650 HPUX core files, and SCO 3.2v2 core files.
5654 Attaching to processes now works again; thanks for the many bug reports.
5656 We have also stomped on a bunch of core dumps caused by
5657 printf_filtered("%s") problems.
5659 We eliminated a copyright problem on the rpc and ptrace header files
5660 for VxWorks, which was discovered at the last minute during the 4.7
5661 release. You should now be able to build a VxWorks GDB.
5663 You can now interrupt gdb while an attached process is running. This
5664 will cause the attached process to stop, and give control back to GDB.
5666 We fixed problems caused by using too many file descriptors
5667 for reading symbols from object files and libraries. This was
5668 especially a problem for programs that used many (~100) shared
5671 The `step' command now only enters a subroutine if there is line number
5672 information for the subroutine. Otherwise it acts like the `next'
5673 command. Previously, `step' would enter subroutines if there was
5674 any debugging information about the routine. This avoids problems
5675 when using `cc -g1' on MIPS machines.
5677 * Internal improvements
5679 GDB's internal interfaces have been improved to make it easier to support
5680 debugging of multiple languages in the future.
5682 GDB now uses a common structure for symbol information internally.
5683 Minimal symbols (derived from linkage symbols in object files), partial
5684 symbols (from a quick scan of debug information), and full symbols
5685 contain a common subset of information, making it easier to write
5686 shared code that handles any of them.
5688 * New command line options
5690 We now accept --silent as an alias for --quiet.
5694 The memory-mapped-malloc library is now licensed under the GNU Library
5695 General Public License.
5697 *** Changes in GDB-4.7:
5699 * Host/native/target split
5701 GDB has had some major internal surgery to untangle the support for
5702 hosts and remote targets. Now, when you configure GDB for a remote
5703 target, it will no longer load in all of the support for debugging
5704 local programs on the host. When fully completed and tested, this will
5705 ensure that arbitrary host/target combinations are possible.
5707 The primary conceptual shift is to separate the non-portable code in
5708 GDB into three categories. Host specific code is required any time GDB
5709 is compiled on that host, regardless of the target. Target specific
5710 code relates to the peculiarities of the target, but can be compiled on
5711 any host. Native specific code is everything else: it can only be
5712 built when the host and target are the same system. Child process
5713 handling and core file support are two common `native' examples.
5715 GDB's use of /proc for controlling Unix child processes is now cleaner.
5716 It has been split out into a single module under the `target_ops' vector,
5717 plus two native-dependent functions for each system that uses /proc.
5719 * New hosts supported
5721 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5722 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5723 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5725 * New targets supported
5727 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5728 68030 and CPU32 m68030-*-*, m68332-*-*
5730 * New native hosts supported
5732 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5733 (386bsd is not well tested yet)
5734 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5736 * New file formats supported
5738 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5739 supports reading of `a.out.adobe' object files, which are an a.out
5740 format extended with minimal information about multiple sections.
5744 `show copying' is the same as the old `info copying'.
5745 `show warranty' is the same as `info warrantee'.
5746 These were renamed for consistency. The old commands continue to work.
5748 `info handle' is a new alias for `info signals'.
5750 You can now define pre-command hooks, which attach arbitrary command
5751 scripts to any command. The commands in the hook will be executed
5752 prior to the user's command. You can also create a hook which will be
5753 executed whenever the program stops. See gdb.texinfo.
5757 We now deal with Cfront style name mangling, and can even extract type
5758 info from mangled symbols. GDB can automatically figure out which
5759 symbol mangling style your C++ compiler uses.
5761 Calling of methods and virtual functions has been improved as well.
5765 The crash that occured when debugging Sun Ansi-C compiled binaries is
5766 fixed. This was due to mishandling of the extra N_SO stabs output
5769 We also finally got Ultrix 4.2 running in house, and fixed core file
5770 support, with help from a dozen people on the net.
5772 John M. Farrell discovered that the reason that single-stepping was so
5773 slow on all of the Mips based platforms (primarily SGI and DEC) was
5774 that we were trying to demangle and lookup a symbol used for internal
5775 purposes on every instruction that was being stepped through. Changing
5776 the name of that symbol so that it couldn't be mistaken for a C++
5777 mangled symbol sped things up a great deal.
5779 Rich Pixley sped up symbol lookups in general by getting much smarter
5780 about when C++ symbol mangling is necessary. This should make symbol
5781 completion (TAB on the command line) much faster. It's not as fast as
5782 we'd like, but it's significantly faster than gdb-4.6.
5786 A new user controllable variable 'call_scratch_address' can
5787 specify the location of a scratch area to be used when GDB
5788 calls a function in the target. This is necessary because the
5789 usual method of putting the scratch area on the stack does not work
5790 in systems that have separate instruction and data spaces.
5792 We integrated changes to support the 29k UDI (Universal Debugger
5793 Interface), but discovered at the last minute that we didn't have all
5794 of the appropriate copyright paperwork. We are working with AMD to
5795 resolve this, and hope to have it available soon.
5799 We have sped up the remote serial line protocol, especially for targets
5800 with lots of registers. It now supports a new `expedited status' ('T')
5801 message which can be used in place of the existing 'S' status message.
5802 This allows the remote stub to send only the registers that GDB
5803 needs to make a quick decision about single-stepping or conditional
5804 breakpoints, eliminating the need to fetch the entire register set for
5805 each instruction being stepped through.
5807 The GDB remote serial protocol now implements a write-through cache for
5808 registers, only re-reading the registers if the target has run.
5810 There is also a new remote serial stub for SPARC processors. You can
5811 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5812 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5813 processor with a serial port.
5817 Configure.in files have become much easier to read and modify. A new
5818 `table driven' format makes it more obvious what configurations are
5819 supported, and what files each one uses.
5823 There is a new opcodes library which will eventually contain all of the
5824 disassembly routines and opcode tables. At present, it only contains
5825 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5826 disassembler (binutils/objdump) to share these routines.
5828 The libiberty library is now copylefted under the GNU Library General
5829 Public License. This allows more liberal use, and was done so libg++
5830 can use it. This makes no difference to GDB, since the Library License
5831 grants all the rights from the General Public License.
5835 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5836 reference to the stabs symbol info used by the debugger. It is (as far
5837 as we know) the only published document on this fascinating topic. We
5838 encourage you to read it, compare it to the stabs information on your
5839 system, and send improvements on the document in general (to
5840 bug-gdb@prep.ai.mit.edu).
5842 And, of course, many bugs have been fixed.
5845 *** Changes in GDB-4.6:
5847 * Better support for C++ function names
5849 GDB now accepts as input the "demangled form" of C++ overloaded function
5850 names and member function names, and can do command completion on such names
5851 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5852 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5853 Make use of command completion, it is your friend.
5855 GDB also now accepts a variety of C++ mangled symbol formats. They are
5856 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5857 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5858 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5859 for the list of formats.
5861 * G++ symbol mangling problem
5863 Recent versions of gcc have a bug in how they emit debugging information for
5864 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5865 directory) can be applied to gcc to fix the problem. Alternatively, if you
5866 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5867 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5868 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5871 * New 'maintenance' command
5873 All of the commands related to hacking GDB internals have been moved out of
5874 the main command set, and now live behind the 'maintenance' command. This
5875 can also be abbreviated as 'mt'. The following changes were made:
5877 dump-me -> maintenance dump-me
5878 info all-breakpoints -> maintenance info breakpoints
5879 printmsyms -> maintenance print msyms
5880 printobjfiles -> maintenance print objfiles
5881 printpsyms -> maintenance print psymbols
5882 printsyms -> maintenance print symbols
5884 The following commands are new:
5886 maintenance demangle Call internal GDB demangler routine to
5887 demangle a C++ link name and prints the result.
5888 maintenance print type Print a type chain for a given symbol
5890 * Change to .gdbinit file processing
5892 We now read the $HOME/.gdbinit file before processing the argv arguments
5893 (e.g. reading symbol files or core files). This allows global parameters to
5894 be set, which will apply during the symbol reading. The ./.gdbinit is still
5895 read after argv processing.
5897 * New hosts supported
5899 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5901 GNU/Linux support i386-unknown-linux or linux
5903 We are also including code to support the HP/PA running BSD and HPUX. This
5904 is almost guaranteed not to work, as we didn't have time to test or build it
5905 for this release. We are including it so that the more adventurous (or
5906 masochistic) of you can play with it. We also had major problems with the
5907 fact that the compiler that we got from HP doesn't support the -g option.
5910 * New targets supported
5912 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5914 * More smarts about finding #include files
5916 GDB now remembers the compilation directory for all include files, and for
5917 all files from which C is generated (like yacc and lex sources). This
5918 greatly improves GDB's ability to find yacc/lex sources, and include files,
5919 especially if you are debugging your program from a directory different from
5920 the one that contains your sources.
5922 We also fixed a bug which caused difficulty with listing and setting
5923 breakpoints in include files which contain C code. (In the past, you had to
5924 try twice in order to list an include file that you hadn't looked at before.)
5926 * Interesting infernals change
5928 GDB now deals with arbitrary numbers of sections, where the symbols for each
5929 section must be relocated relative to that section's landing place in the
5930 target's address space. This work was needed to support ELF with embedded
5931 stabs used by Solaris-2.0.
5933 * Bug fixes (of course!)
5935 There have been loads of fixes for the following things:
5936 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5937 i960, stabs, DOS(GO32), procfs, etc...
5939 See the ChangeLog for details.
5941 *** Changes in GDB-4.5:
5943 * New machines supported (host and target)
5945 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5947 SGI Irix-4.x mips-sgi-irix4 or iris4
5949 * New malloc package
5951 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5952 Mmalloc is capable of handling mutiple heaps of memory. It is also
5953 capable of saving a heap to a file, and then mapping it back in later.
5954 This can be used to greatly speedup the startup of GDB by using a
5955 pre-parsed symbol table which lives in a mmalloc managed heap. For
5956 more details, please read mmalloc/mmalloc.texi.
5960 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5961 'help info proc' for details.
5963 * MIPS ecoff symbol table format
5965 The code that reads MIPS symbol table format is now supported on all hosts.
5966 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5969 * File name changes for MS-DOS
5971 Many files in the config directories have been renamed to make it easier to
5972 support GDB on MS-DOSe systems (which have very restrictive file name
5973 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5974 environment) is close to working but has some remaining problems. Note
5975 that debugging of DOS programs is not supported, due to limitations
5976 in the ``operating system'', but it can be used to host cross-debugging.
5978 * Cross byte order fixes
5980 Many fixes have been made to support cross debugging of Sparc and MIPS
5981 targets from hosts whose byte order differs.
5983 * New -mapped and -readnow options
5985 If memory-mapped files are available on your system through the 'mmap'
5986 system call, you can use the -mapped option on the `file' or
5987 `symbol-file' commands to cause GDB to write the symbols from your
5988 program into a reusable file. If the program you are debugging is
5989 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5990 Future GDB debugging sessions will notice the presence of this file,
5991 and will quickly map in symbol information from it, rather than reading
5992 the symbol table from the executable program. Using the '-mapped'
5993 option in a GDB `file' or `symbol-file' command has the same effect as
5994 starting GDB with the '-mapped' command-line option.
5996 You can cause GDB to read the entire symbol table immediately by using
5997 the '-readnow' option with any of the commands that load symbol table
5998 information (or on the GDB command line). This makes the command
5999 slower, but makes future operations faster.
6001 The -mapped and -readnow options are typically combined in order to
6002 build a `fred.syms' file that contains complete symbol information.
6003 A simple GDB invocation to do nothing but build a `.syms' file for future
6006 gdb -batch -nx -mapped -readnow programname
6008 The `.syms' file is specific to the host machine on which GDB is run.
6009 It holds an exact image of GDB's internal symbol table. It cannot be
6010 shared across multiple host platforms.
6012 * longjmp() handling
6014 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6015 siglongjmp() without losing control. This feature has not yet been ported to
6016 all systems. It currently works on many 386 platforms, all MIPS-based
6017 platforms (SGI, DECstation, etc), and Sun3/4.
6021 Preliminary work has been put in to support the new Solaris OS from Sun. At
6022 this time, it can control and debug processes, but it is not capable of
6027 As always, many many bug fixes. The major areas were with g++, and mipsread.
6028 People using the MIPS-based platforms should experience fewer mysterious
6029 crashes and trashed symbol tables.
6031 *** Changes in GDB-4.4:
6033 * New machines supported (host and target)
6035 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6037 BSD Reno on Vax vax-dec-bsd
6038 Ultrix on Vax vax-dec-ultrix
6040 * New machines supported (target)
6042 AMD 29000 embedded, using EBMON a29k-none-none
6046 GDB continues to improve its handling of C++. `References' work better.
6047 The demangler has also been improved, and now deals with symbols mangled as
6048 per the Annotated C++ Reference Guide.
6050 GDB also now handles `stabs' symbol information embedded in MIPS
6051 `ecoff' symbol tables. Since the ecoff format was not easily
6052 extensible to handle new languages such as C++, this appeared to be a
6053 good way to put C++ debugging info into MIPS binaries. This option
6054 will be supported in the GNU C compiler, version 2, when it is
6057 * New features for SVR4
6059 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6060 shared libraries. Debugging dynamically linked programs should present
6061 only minor differences from debugging statically linked programs.
6063 The `info proc' command will print out information about any process
6064 on an SVR4 system (including the one you are debugging). At the moment,
6065 it prints the address mappings of the process.
6067 If you bring up GDB on another SVR4 system, please send mail to
6068 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6070 * Better dynamic linking support in SunOS
6072 Reading symbols from shared libraries which contain debugging symbols
6073 now works properly. However, there remain issues such as automatic
6074 skipping of `transfer vector' code during function calls, which
6075 make it harder to debug code in a shared library, than to debug the
6076 same code linked statically.
6080 GDB is now using the latest `getopt' routines from the FSF. This
6081 version accepts the -- prefix for options with long names. GDB will
6082 continue to accept the old forms (-option and +option) as well.
6083 Various single letter abbreviations for options have been explicity
6084 added to the option table so that they won't get overshadowed in the
6085 future by other options that begin with the same letter.
6089 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6090 Many assorted bugs have been handled. Many more remain to be handled.
6091 See the various ChangeLog files (primarily in gdb and bfd) for details.
6094 *** Changes in GDB-4.3:
6096 * New machines supported (host and target)
6098 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6099 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6100 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6102 * Almost SCO Unix support
6104 We had hoped to support:
6105 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6106 (except for core file support), but we discovered very late in the release
6107 that it has problems with process groups that render gdb unusable. Sorry
6108 about that. I encourage people to fix it and post the fixes.
6110 * Preliminary ELF and DWARF support
6112 GDB can read ELF object files on System V Release 4, and can handle
6113 debugging records for C, in DWARF format, in ELF files. This support
6114 is preliminary. If you bring up GDB on another SVR4 system, please
6115 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6120 GDB now uses the latest `readline' library. One user-visible change
6121 is that two tabs will list possible command completions, which previously
6122 required typing M-? (meta-question mark, or ESC ?).
6126 The `stepi' bug that many of you noticed has been squashed.
6127 Many bugs in C++ have been handled. Many more remain to be handled.
6128 See the various ChangeLog files (primarily in gdb and bfd) for details.
6130 * State of the MIPS world (in case you wondered):
6132 GDB can understand the symbol tables emitted by the compilers
6133 supplied by most vendors of MIPS-based machines, including DEC. These
6134 symbol tables are in a format that essentially nobody else uses.
6136 Some versions of gcc come with an assembler post-processor called
6137 mips-tfile. This program is required if you want to do source-level
6138 debugging of gcc-compiled programs. I believe FSF does not ship
6139 mips-tfile with gcc version 1, but it will eventually come with gcc
6142 Debugging of g++ output remains a problem. g++ version 1.xx does not
6143 really support it at all. (If you're lucky, you should be able to get
6144 line numbers and stack traces to work, but no parameters or local
6145 variables.) With some work it should be possible to improve the
6148 When gcc version 2 is released, you will have somewhat better luck.
6149 However, even then you will get confusing results for inheritance and
6152 We will eventually provide full debugging of g++ output on
6153 DECstations. This will probably involve some kind of stabs-in-ecoff
6154 encapulation, but the details have not been worked out yet.
6157 *** Changes in GDB-4.2:
6159 * Improved configuration
6161 Only one copy of `configure' exists now, and it is not self-modifying.
6162 Porting BFD is simpler.
6166 The `step' and `next' commands now only stop at the first instruction
6167 of a source line. This prevents the multiple stops that used to occur
6168 in switch statements, for-loops, etc. `Step' continues to stop if a
6169 function that has debugging information is called within the line.
6173 Lots of small bugs fixed. More remain.
6175 * New host supported (not target)
6177 Intel 386 PC clone running Mach i386-none-mach
6180 *** Changes in GDB-4.1:
6182 * Multiple source language support
6184 GDB now has internal scaffolding to handle several source languages.
6185 It determines the type of each source file from its filename extension,
6186 and will switch expression parsing and number formatting to match the
6187 language of the function in the currently selected stack frame.
6188 You can also specifically set the language to be used, with
6189 `set language c' or `set language modula-2'.
6193 GDB now has preliminary support for the GNU Modula-2 compiler,
6194 currently under development at the State University of New York at
6195 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6196 continue through the fall of 1991 and into 1992.
6198 Other Modula-2 compilers are currently not supported, and attempting to
6199 debug programs compiled with them will likely result in an error as the
6200 symbol table is read. Feel free to work on it, though!
6202 There are hooks in GDB for strict type checking and range checking,
6203 in the `Modula-2 philosophy', but they do not currently work.
6207 GDB can now write to executable and core files (e.g. patch
6208 a variable's value). You must turn this switch on, specify
6209 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6210 by assigning a new value to a variable. Modifications take
6213 * Automatic SunOS shared library reading
6215 When you run your program, GDB automatically determines where its
6216 shared libraries (if any) have been loaded, and reads their symbols.
6217 The `share' command is no longer needed. This also works when
6218 examining core files.
6222 You can specify the number of lines that the `list' command shows.
6225 * New machines supported (host and target)
6227 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6228 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6229 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6231 * New hosts supported (not targets)
6233 IBM RT/PC: romp-ibm-aix or rtpc
6235 * New targets supported (not hosts)
6237 AMD 29000 embedded with COFF a29k-none-coff
6238 AMD 29000 embedded with a.out a29k-none-aout
6239 Ultracomputer remote kernel debug a29k-nyu-kern
6241 * New remote interfaces
6247 *** Changes in GDB-4.0:
6251 Wide output is wrapped at good places to make the output more readable.
6253 Gdb now supports cross-debugging from a host machine of one type to a
6254 target machine of another type. Communication with the target system
6255 is over serial lines. The ``target'' command handles connecting to the
6256 remote system; the ``load'' command will download a program into the
6257 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6258 also supports debugging of realtime processes running under VxWorks,
6259 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6260 stub on the target system.
6262 New CPUs supported include the AMD 29000 and Intel 960.
6264 GDB now reads object files and symbol tables via a ``binary file''
6265 library, which allows a single copy of GDB to debug programs of multiple
6266 object file types such as a.out and coff.
6268 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6269 refcard.dvi and refcard.ps are available to format it).
6272 * Control-Variable user interface simplified
6274 All variables that control the operation of the debugger can be set
6275 by the ``set'' command, and displayed by the ``show'' command.
6277 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6278 ``Show prompt'' produces the response:
6279 Gdb's prompt is new-gdb=>.
6281 What follows are the NEW set commands. The command ``help set'' will
6282 print a complete list of old and new set commands. ``help set FOO''
6283 will give a longer description of the variable FOO. ``show'' will show
6284 all of the variable descriptions and their current settings.
6286 confirm on/off: Enables warning questions for operations that are
6287 hard to recover from, e.g. rerunning the program while
6288 it is already running. Default is ON.
6290 editing on/off: Enables EMACS style command line editing
6291 of input. Previous lines can be recalled with
6292 control-P, the current line can be edited with control-B,
6293 you can search for commands with control-R, etc.
6296 history filename NAME: NAME is where the gdb command history
6297 will be stored. The default is .gdb_history,
6298 or the value of the environment variable
6301 history size N: The size, in commands, of the command history. The
6302 default is 256, or the value of the environment variable
6305 history save on/off: If this value is set to ON, the history file will
6306 be saved after exiting gdb. If set to OFF, the
6307 file will not be saved. The default is OFF.
6309 history expansion on/off: If this value is set to ON, then csh-like
6310 history expansion will be performed on
6311 command line input. The default is OFF.
6313 radix N: Sets the default radix for input and output. It can be set
6314 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6315 in the current radix, so "set radix 10" is always a no-op.
6317 height N: This integer value is the number of lines on a page. Default
6318 is 24, the current `stty rows'' setting, or the ``li#''
6319 setting from the termcap entry matching the environment
6322 width N: This integer value is the number of characters on a line.
6323 Default is 80, the current `stty cols'' setting, or the ``co#''
6324 setting from the termcap entry matching the environment
6327 Note: ``set screensize'' is obsolete. Use ``set height'' and
6328 ``set width'' instead.
6330 print address on/off: Print memory addresses in various command displays,
6331 such as stack traces and structure values. Gdb looks
6332 more ``symbolic'' if you turn this off; it looks more
6333 ``machine level'' with it on. Default is ON.
6335 print array on/off: Prettyprint arrays. New convenient format! Default
6338 print demangle on/off: Print C++ symbols in "source" form if on,
6341 print asm-demangle on/off: Same, for assembler level printouts
6344 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6347 * Support for Epoch Environment.
6349 The epoch environment is a version of Emacs v18 with windowing. One
6350 new command, ``inspect'', is identical to ``print'', except that if you
6351 are running in the epoch environment, the value is printed in its own
6355 * Support for Shared Libraries
6357 GDB can now debug programs and core files that use SunOS shared libraries.
6358 Symbols from a shared library cannot be referenced
6359 before the shared library has been linked with the program (this
6360 happens after you type ``run'' and before the function main() is entered).
6361 At any time after this linking (including when examining core files
6362 from dynamically linked programs), gdb reads the symbols from each
6363 shared library when you type the ``sharedlibrary'' command.
6364 It can be abbreviated ``share''.
6366 sharedlibrary REGEXP: Load shared object library symbols for files
6367 matching a unix regular expression. No argument
6368 indicates to load symbols for all shared libraries.
6370 info sharedlibrary: Status of loaded shared libraries.
6375 A watchpoint stops execution of a program whenever the value of an
6376 expression changes. Checking for this slows down execution
6377 tremendously whenever you are in the scope of the expression, but is
6378 quite useful for catching tough ``bit-spreader'' or pointer misuse
6379 problems. Some machines such as the 386 have hardware for doing this
6380 more quickly, and future versions of gdb will use this hardware.
6382 watch EXP: Set a watchpoint (breakpoint) for an expression.
6384 info watchpoints: Information about your watchpoints.
6386 delete N: Deletes watchpoint number N (same as breakpoints).
6387 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6388 enable N: Re-enables watchpoint number N (same as breakpoints).
6391 * C++ multiple inheritance
6393 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6396 * C++ exception handling
6398 Gdb now supports limited C++ exception handling. Besides the existing
6399 ability to breakpoint on an exception handler, gdb can breakpoint on
6400 the raising of an exception (before the stack is peeled back to the
6403 catch FOO: If there is a FOO exception handler in the dynamic scope,
6404 set a breakpoint to catch exceptions which may be raised there.
6405 Multiple exceptions (``catch foo bar baz'') may be caught.
6407 info catch: Lists all exceptions which may be caught in the
6408 current stack frame.
6411 * Minor command changes
6413 The command ``call func (arg, arg, ...)'' now acts like the print
6414 command, except it does not print or save a value if the function's result
6415 is void. This is similar to dbx usage.
6417 The ``up'' and ``down'' commands now always print the frame they end up
6418 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6419 frames without printing.
6421 * New directory command
6423 'dir' now adds directories to the FRONT of the source search path.
6424 The path starts off empty. Source files that contain debug information
6425 about the directory in which they were compiled can be found even
6426 with an empty path; Sun CC and GCC include this information. If GDB can't
6427 find your source file in the current directory, type "dir .".
6429 * Configuring GDB for compilation
6431 For normal use, type ``./configure host''. See README or gdb.texinfo
6434 GDB now handles cross debugging. If you are remotely debugging between
6435 two different machines, type ``./configure host -target=targ''.
6436 Host is the machine where GDB will run; targ is the machine
6437 where the program that you are debugging will run.
projects / external / binutils.git / blob