1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.11
6 * GDB now supports multibit bitfields and enums in target register
9 * New Python-based convenience function $_as_string(val), which returns
10 the textual representation of a value. This function is especially
11 useful to obtain the text label of an enum value.
13 * Intel MPX bound violation handling.
15 Segmentation faults caused by a Intel MPX boundary violation
16 now display the kind of violation (upper or lower), the memory
17 address accessed and the memory bounds, along with the usual
18 signal received and code location.
22 Program received signal SIGSEGV, Segmentation fault
23 Upper bound violation while accessing address 0x7fffffffc3b3
24 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
25 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
30 skip -gfile file-glob-pattern
31 skip -function function
32 skip -rfunction regular-expression
33 A generalized form of the skip command, with new support for
34 glob-style file names and regular expressions for function names.
35 Additionally, a file spec and a function spec may now be combined.
37 maint info line-table REGEXP
38 Display the contents of GDB's internal line table data struture.
40 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
41 was added in GDBserver, including JIT compiling fast tracepoint's
42 conditional expression bytecode into native code.
44 * Support for various remote target protocols and ROM monitors has
47 target m32rsdi Remote M32R debugging over SDI
48 target mips MIPS remote debugging protocol
49 target pmon PMON ROM monitor
50 target ddb NEC's DDB variant of PMON for Vr4300
51 target rockhopper NEC RockHopper variant of PMON
52 target lsi LSI variant of PMO
54 *** Changes in GDB 7.11
56 * GDB now supports debugging kernel-based threads on FreeBSD.
58 * Per-inferior thread numbers
60 Thread numbers are now per inferior instead of global. If you're
61 debugging multiple inferiors, GDB displays thread IDs using a
62 qualified INF_NUM.THR_NUM form. For example:
66 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
67 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
68 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
69 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
71 As consequence, thread numbers as visible in the $_thread
72 convenience variable and in Python's InferiorThread.num attribute
73 are no longer unique between inferiors.
75 GDB now maintains a second thread ID per thread, referred to as the
76 global thread ID, which is the new equivalent of thread numbers in
77 previous releases. See also $_gthread below.
79 For backwards compatibility, MI's thread IDs always refer to global
82 * Commands that accept thread IDs now accept the qualified
83 INF_NUM.THR_NUM form as well. For example:
86 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
89 * In commands that accept a list of thread IDs, you can now refer to
90 all threads of an inferior using a star wildcard. GDB accepts
91 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
92 refer to all threads of the current inferior. For example, "info
95 * You can use "info threads -gid" to display the global thread ID of
98 * The new convenience variable $_gthread holds the global number of
101 * The new convenience variable $_inferior holds the number of the
104 * GDB now displays the ID and name of the thread that hit a breakpoint
105 or received a signal, if your program is multi-threaded. For
108 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
109 Thread 1 "main" received signal SIGINT, Interrupt.
111 * Record btrace now supports non-stop mode.
113 * Support for tracepoints on aarch64-linux was added in GDBserver.
115 * The 'record instruction-history' command now indicates speculative execution
116 when using the Intel Processor Trace recording format.
118 * GDB now allows users to specify explicit locations, bypassing
119 the linespec parser. This feature is also available to GDB/MI
122 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
123 GDB now is able to debug both AArch64 applications and ARM applications
126 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
127 including JIT compiling fast tracepoint's conditional expression bytecode
130 * GDB now supports displaced stepping on AArch64 GNU/Linux.
132 * "info threads", "info inferiors", "info display", "info checkpoints"
133 and "maint info program-spaces" now list the corresponding items in
134 ascending ID order, for consistency with all other "info" commands.
136 * In Ada, the overloads selection menu has been enhanced to display the
137 parameter types and the return types for the matching overloaded subprograms.
141 maint set target-non-stop (on|off|auto)
142 maint show target-non-stop
143 Control whether GDB targets always operate in non-stop mode even if
144 "set non-stop" is "off". The default is "auto", meaning non-stop
145 mode is enabled if supported by the target.
147 maint set bfd-sharing
148 maint show bfd-sharing
149 Control the reuse of bfd objects.
153 Control display of debugging info regarding bfd caching.
157 Control display of debugging info regarding FreeBSD threads.
159 set remote multiprocess-extensions-packet
160 show remote multiprocess-extensions-packet
161 Set/show the use of the remote protocol multiprocess extensions.
163 set remote thread-events
164 show remote thread-events
165 Set/show the use of thread create/exit events.
167 set ada print-signatures on|off
168 show ada print-signatures"
169 Control whether parameter types and return types are displayed in overloads
170 selection menus. It is activaled (@code{on}) by default.
174 Controls the maximum size of memory, in bytes, that GDB will
175 allocate for value contents. Prevents incorrect programs from
176 causing GDB to allocate overly large buffers. Default is 64k.
178 * The "disassemble" command accepts a new modifier: /s.
179 It prints mixed source+disassembly like /m with two differences:
180 - disassembled instructions are now printed in program order, and
181 - and source for all relevant files is now printed.
182 The "/m" option is now considered deprecated: its "source-centric"
183 output hasn't proved useful in practice.
185 * The "record instruction-history" command accepts a new modifier: /s.
186 It behaves exactly like /m and prints mixed source+disassembly.
188 * The "set scheduler-locking" command supports a new mode "replay".
189 It behaves like "off" in record mode and like "on" in replay mode.
191 * Support for various ROM monitors has been removed:
193 target dbug dBUG ROM monitor for Motorola ColdFire
194 target picobug Motorola picobug monitor
195 target dink32 DINK32 ROM monitor for PowerPC
196 target m32r Renesas M32R/D ROM monitor
197 target mon2000 mon2000 ROM monitor
198 target ppcbug PPCBUG ROM monitor for PowerPC
200 * Support for reading/writing memory and extracting values on architectures
201 whose memory is addressable in units of any integral multiple of 8 bits.
206 Indicates that an exec system call was executed.
208 exec-events feature in qSupported
209 The qSupported packet allows GDB to request support for exec
210 events using the new 'gdbfeature' exec-event, and the qSupported
211 response can contain the corresponding 'stubfeature'. Set and
212 show commands can be used to display whether these features are enabled.
215 Equivalent to interrupting with the ^C character, but works in
218 thread created stop reason (T05 create:...)
219 Indicates that the thread was just created and is stopped at entry.
221 thread exit stop reply (w exitcode;tid)
222 Indicates that the thread has terminated.
225 Enables/disables thread create and exit event reporting. For
226 example, this is used in non-stop mode when GDB stops a set of
227 threads and synchronously waits for the their corresponding stop
228 replies. Without exit events, if one of the threads exits, GDB
229 would hang forever not knowing that it should no longer expect a
230 stop for that same thread.
234 Indicates that there are no resumed threads left in the target (all
235 threads are stopped). The remote stub reports support for this stop
236 reply to GDB's qSupported query.
238 QCatchSyscalls:1 [;SYSNO]...
240 Enable ("QCatchSyscalls:1") or disable ("QCatchSyscalls:0")
241 catching syscalls from the inferior process.
243 syscall_entry stop reason
244 Indicates that a syscall was just called.
246 syscall_return stop reason
247 Indicates that a syscall just returned.
249 QCatchSyscalls:1 in qSupported
250 The qSupported packet may now include QCatchSyscalls:1 in the reply
251 to indicate support for catching syscalls.
253 * Extended-remote exec events
255 ** GDB now has support for exec events on extended-remote Linux targets.
256 For such targets with Linux kernels 2.5.46 and later, this enables
257 follow-exec-mode and exec catchpoints.
259 set remote exec-event-feature-packet
260 show remote exec-event-feature-packet
261 Set/show the use of the remote exec event feature.
263 * Thread names in remote protocol
265 The reply to qXfer:threads:read may now include a name attribute for each
268 * Target remote mode fork and exec events
270 ** GDB now has support for fork and exec events on target remote mode
271 Linux targets. For such targets with Linux kernels 2.5.46 and later,
272 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
273 fork and exec catchpoints.
275 * Remote syscall events
277 ** GDB now has support for catch syscall on remote Linux targets,
278 currently enabled on x86/x86_64 architectures.
280 set remote catch-syscall-packet
281 show remote catch-syscall-packet
282 Set/show the use of the remote catch syscall feature.
286 ** The -var-set-format command now accepts the zero-hexadecimal
287 format. It outputs data in hexadecimal format with zero-padding on the
292 ** gdb.InferiorThread objects have a new attribute "global_num",
293 which refers to the thread's global thread ID. The existing
294 "num" attribute now refers to the thread's per-inferior number.
295 See "Per-inferior thread numbers" above.
296 ** gdb.InferiorThread objects have a new attribute "inferior", which
297 is the Inferior object the thread belongs to.
299 *** Changes in GDB 7.10
301 * Support for process record-replay and reverse debugging on aarch64*-linux*
302 targets has been added. GDB now supports recording of A64 instruction set
303 including advance SIMD instructions.
305 * Support for Sun's version of the "stabs" debug file format has been removed.
307 * GDB now honors the content of the file /proc/PID/coredump_filter
308 (PID is the process ID) on GNU/Linux systems. This file can be used
309 to specify the types of memory mappings that will be included in a
310 corefile. For more information, please refer to the manual page of
311 "core(5)". GDB also has a new command: "set use-coredump-filter
312 on|off". It allows to set whether GDB will read the content of the
313 /proc/PID/coredump_filter file when generating a corefile.
315 * The "info os" command on GNU/Linux can now display information on
317 "info os cpus" Listing of all cpus/cores on the system
319 * GDB has two new commands: "set serial parity odd|even|none" and
320 "show serial parity". These allows to set or show parity for the
323 * The "info source" command now displays the producer string if it was
324 present in the debug info. This typically includes the compiler version
325 and may include things like its command line arguments.
327 * The "info dll", an alias of the "info sharedlibrary" command,
328 is now available on all platforms.
330 * Directory names supplied to the "set sysroot" commands may be
331 prefixed with "target:" to tell GDB to access shared libraries from
332 the target system, be it local or remote. This replaces the prefix
333 "remote:". The default sysroot has been changed from "" to
334 "target:". "remote:" is automatically converted to "target:" for
335 backward compatibility.
337 * The system root specified by "set sysroot" will be prepended to the
338 filename of the main executable (if reported to GDB as absolute by
339 the operating system) when starting processes remotely, and when
340 attaching to already-running local or remote processes.
342 * GDB now supports automatic location and retrieval of executable
343 files from remote targets. Remote debugging can now be initiated
344 using only a "target remote" or "target extended-remote" command
345 (no "set sysroot" or "file" commands are required). See "New remote
348 * The "dump" command now supports verilog hex format.
350 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
352 * On GNU/Linux, GDB and gdbserver are now able to access executable
353 and shared library files without a "set sysroot" command when
354 attaching to processes running in different mount namespaces from
355 the debugger. This makes it possible to attach to processes in
356 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
357 See "New remote packets" below.
359 * The "tui reg" command now provides completion for all of the
360 available register groups, including target specific groups.
362 * The HISTSIZE environment variable is no longer read when determining
363 the size of GDB's command history. GDB now instead reads the dedicated
364 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
365 disables truncation of command history. Non-numeric values of GDBHISTSIZE
370 ** Memory ports can now be unbuffered.
374 ** gdb.Objfile objects have a new attribute "username",
375 which is the name of the objfile as specified by the user,
376 without, for example, resolving symlinks.
377 ** You can now write frame unwinders in Python.
378 ** gdb.Type objects have a new method "optimized_out",
379 returning optimized out gdb.Value instance of this type.
380 ** gdb.Value objects have new methods "reference_value" and
381 "const_value" which return a reference to the value and a
382 "const" version of the value respectively.
386 maint print symbol-cache
387 Print the contents of the symbol cache.
389 maint print symbol-cache-statistics
390 Print statistics of symbol cache usage.
392 maint flush-symbol-cache
393 Flush the contents of the symbol cache.
397 Start branch trace recording using Branch Trace Store (BTS) format.
400 Evaluate expression by using the compiler and print result.
404 Explicit commands for enabling and disabling tui mode.
407 set mpx bound on i386 and amd64
408 Support for bound table investigation on Intel MPX enabled applications.
412 Start branch trace recording using Intel Processor Trace format.
415 Print information about branch tracing internals.
417 maint btrace packet-history
418 Print the raw branch tracing data.
420 maint btrace clear-packet-history
421 Discard the stored raw branch tracing data.
424 Discard all branch tracing data. It will be fetched and processed
425 anew by the next "record" command.
430 Renamed from "set debug dwarf2-die".
432 Renamed from "show debug dwarf2-die".
435 Renamed from "set debug dwarf2-read".
436 show debug dwarf-read
437 Renamed from "show debug dwarf2-read".
439 maint set dwarf always-disassemble
440 Renamed from "maint set dwarf2 always-disassemble".
441 maint show dwarf always-disassemble
442 Renamed from "maint show dwarf2 always-disassemble".
444 maint set dwarf max-cache-age
445 Renamed from "maint set dwarf2 max-cache-age".
446 maint show dwarf max-cache-age
447 Renamed from "maint show dwarf2 max-cache-age".
450 show debug dwarf-line
451 Control display of debugging info regarding DWARF line processing.
455 Set the maximum number of candidates to be considered during
456 completion. The default value is 200. This limit allows GDB
457 to avoid generating large completion lists, the computation of
458 which can cause the debugger to become temporarily unresponsive.
460 set history remove-duplicates
461 show history remove-duplicates
462 Control the removal of duplicate history entries.
464 maint set symbol-cache-size
465 maint show symbol-cache-size
466 Control the size of the symbol cache.
468 set|show record btrace bts buffer-size
469 Set and show the size of the ring buffer used for branch tracing in
471 The obtained size may differ from the requested size. Use "info
472 record" to see the obtained buffer size.
474 set debug linux-namespaces
475 show debug linux-namespaces
476 Control display of debugging info regarding Linux namespaces.
478 set|show record btrace pt buffer-size
479 Set and show the size of the ring buffer used for branch tracing in
480 Intel Processor Trace format.
481 The obtained size may differ from the requested size. Use "info
482 record" to see the obtained buffer size.
484 maint set|show btrace pt skip-pad
485 Set and show whether PAD packets are skipped when computing the
488 * The command 'thread apply all' can now support new option '-ascending'
489 to call its specified command for all threads in ascending order.
491 * Python/Guile scripting
493 ** GDB now supports auto-loading of Python/Guile scripts contained in the
494 special section named `.debug_gdb_scripts'.
498 qXfer:btrace-conf:read
499 Return the branch trace configuration for the current thread.
501 Qbtrace-conf:bts:size
502 Set the requested ring buffer size for branch tracing in BTS format.
505 Enable Intel Procesor Trace-based branch tracing for the current
506 process. The remote stub reports support for this packet to GDB's
510 Set the requested ring buffer size for branch tracing in Intel Processor
514 Indicates a memory breakpoint instruction was executed, irrespective
515 of whether it was GDB that planted the breakpoint or the breakpoint
516 is hardcoded in the program. This is required for correct non-stop
520 Indicates the target stopped for a hardware breakpoint. This is
521 required for correct non-stop mode operation.
524 Return information about files on the remote system.
527 Return the full absolute name of the file that was executed to
528 create a process running on the remote system.
531 Select the filesystem on which vFile: operations with filename
532 arguments will operate. This is required for GDB to be able to
533 access files on remote targets where the remote stub does not
534 share a common filesystem with the inferior(s).
537 Indicates that a fork system call was executed.
540 Indicates that a vfork system call was executed.
542 vforkdone stop reason
543 Indicates that a vfork child of the specified process has executed
544 an exec or exit, allowing the vfork parent to resume execution.
546 fork-events and vfork-events features in qSupported
547 The qSupported packet allows GDB to request support for fork and
548 vfork events using new 'gdbfeatures' fork-events and vfork-events,
549 and the qSupported response can contain the corresponding
550 'stubfeatures'. Set and show commands can be used to display
551 whether these features are enabled.
553 * Extended-remote fork events
555 ** GDB now has support for fork events on extended-remote Linux
556 targets. For targets with Linux kernels 2.5.60 and later, this
557 enables follow-fork-mode and detach-on-fork for both fork and
558 vfork, as well as fork and vfork catchpoints.
560 * The info record command now shows the recording format and the
561 branch tracing configuration for the current thread when using
562 the btrace record target.
563 For the BTS format, it shows the ring buffer size.
565 * GDB now has support for DTrace USDT (Userland Static Defined
566 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
568 * GDB now supports access to vector registers on S/390 GNU/Linux
571 * Removed command line options
573 -xdb HP-UX XDB compatibility mode.
575 * Removed targets and native configurations
577 HP/PA running HP-UX hppa*-*-hpux*
578 Itanium running HP-UX ia64-*-hpux*
580 * New configure options
583 This configure option allows the user to build GDB with support for
584 Intel Processor Trace (default: auto). This requires libipt.
586 --with-libipt-prefix=PATH
587 Specify the path to the version of libipt that GDB should use.
588 $PATH/include should contain the intel-pt.h header and
589 $PATH/lib should contain the libipt.so library.
591 *** Changes in GDB 7.9.1
595 ** Xmethods can now specify a result type.
597 *** Changes in GDB 7.9
599 * GDB now supports hardware watchpoints on x86 GNU Hurd.
603 ** You can now access frame registers from Python scripts.
604 ** New attribute 'producer' for gdb.Symtab objects.
605 ** gdb.Objfile objects have a new attribute "progspace",
606 which is the gdb.Progspace object of the containing program space.
607 ** gdb.Objfile objects have a new attribute "owner".
608 ** gdb.Objfile objects have a new attribute "build_id",
609 which is the build ID generated when the file was built.
610 ** gdb.Objfile objects have a new method "add_separate_debug_file".
611 ** A new event "gdb.clear_objfiles" has been added, triggered when
612 selecting a new file to debug.
613 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
614 ** New function gdb.lookup_objfile.
616 New events which are triggered when GDB modifies the state of the
619 ** gdb.events.inferior_call_pre: Function call is about to be made.
620 ** gdb.events.inferior_call_post: Function call has just been made.
621 ** gdb.events.memory_changed: A memory location has been altered.
622 ** gdb.events.register_changed: A register has been altered.
624 * New Python-based convenience functions:
626 ** $_caller_is(name [, number_of_frames])
627 ** $_caller_matches(regexp [, number_of_frames])
628 ** $_any_caller_is(name [, number_of_frames])
629 ** $_any_caller_matches(regexp [, number_of_frames])
631 * GDB now supports the compilation and injection of source code into
632 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
633 to compile the source code to object code, and if successful, inject
634 and execute that code within the current context of the inferior.
635 Currently the C language is supported. The commands used to
636 interface with this new feature are:
638 compile code [-raw|-r] [--] [source code]
639 compile file [-raw|-r] filename
643 demangle [-l language] [--] name
644 Demangle "name" in the specified language, or the current language
645 if elided. This command is renamed from the "maint demangle" command.
646 The latter is kept as a no-op to avoid "maint demangle" being interpreted
647 as "maint demangler-warning".
649 queue-signal signal-name-or-number
650 Queue a signal to be delivered to the thread when it is resumed.
652 add-auto-load-scripts-directory directory
653 Add entries to the list of directories from which to load auto-loaded
656 maint print user-registers
657 List all currently available "user" registers.
659 compile code [-r|-raw] [--] [source code]
660 Compile, inject, and execute in the inferior the executable object
661 code produced by compiling the provided source code.
663 compile file [-r|-raw] filename
664 Compile and inject into the inferior the executable object code
665 produced by compiling the source code stored in the filename
668 * On resume, GDB now always passes the signal the program had stopped
669 for to the thread the signal was sent to, even if the user changed
670 threads before resuming. Previously GDB would often (but not
671 always) deliver the signal to the thread that happens to be current
674 * Conversely, the "signal" command now consistently delivers the
675 requested signal to the current thread. GDB now asks for
676 confirmation if the program had stopped for a signal and the user
677 switched threads meanwhile.
679 * "breakpoint always-inserted" modes "off" and "auto" merged.
681 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
682 won't remove breakpoints from the target until all threads stop,
683 even in non-stop mode. The "auto" mode has been removed, and "off"
684 is now the default mode.
688 set debug symbol-lookup
689 show debug symbol-lookup
690 Control display of debugging info regarding symbol lookup.
694 ** The -list-thread-groups command outputs an exit-code field for
695 inferiors that have exited.
699 MIPS SDE mips*-sde*-elf*
703 Support for these obsolete configurations has been removed.
705 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
706 SGI Irix-5.x mips-*-irix5*
707 SGI Irix-6.x mips-*-irix6*
708 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
709 VAX running Ultrix vax-*-ultrix*
711 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
712 and "assf"), have been removed. Use the "sharedlibrary" command, or
713 its alias "share", instead.
715 *** Changes in GDB 7.8
717 * New command line options
720 This is an alias for the --data-directory option.
722 * GDB supports printing and modifying of variable length automatic arrays
723 as specified in ISO C99.
725 * The ARM simulator now supports instruction level tracing
726 with or without disassembly.
730 GDB now has support for scripting using Guile. Whether this is
731 available is determined at configure time.
732 Guile version 2.0 or greater is required.
733 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
735 * New commands (for set/show, see "New options" below)
739 Invoke CODE by passing it to the Guile interpreter.
743 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
745 info auto-load guile-scripts [regexp]
746 Print the list of automatically loaded Guile scripts.
748 * The source command is now capable of sourcing Guile scripts.
749 This feature is dependent on the debugger being built with Guile support.
753 set print symbol-loading (off|brief|full)
754 show print symbol-loading
755 Control whether to print informational messages when loading symbol
756 information for a file. The default is "full", but when debugging
757 programs with large numbers of shared libraries the amount of output
760 set guile print-stack (none|message|full)
761 show guile print-stack
762 Show a stack trace when an error is encountered in a Guile script.
764 set auto-load guile-scripts (on|off)
765 show auto-load guile-scripts
766 Control auto-loading of Guile script files.
768 maint ada set ignore-descriptive-types (on|off)
769 maint ada show ignore-descriptive-types
770 Control whether the debugger should ignore descriptive types in Ada
771 programs. The default is not to ignore the descriptive types. See
772 the user manual for more details on descriptive types and the intended
773 usage of this option.
775 set auto-connect-native-target
777 Control whether GDB is allowed to automatically connect to the
778 native target for the run, attach, etc. commands when not connected
779 to any target yet. See also "target native" below.
781 set record btrace replay-memory-access (read-only|read-write)
782 show record btrace replay-memory-access
783 Control what memory accesses are allowed during replay.
785 maint set target-async (on|off)
786 maint show target-async
787 This controls whether GDB targets operate in synchronous or
788 asynchronous mode. Normally the default is asynchronous, if it is
789 available; but this can be changed to more easily debug problems
790 occurring only in synchronous mode.
792 set mi-async (on|off)
794 Control whether MI asynchronous mode is preferred. This supersedes
795 "set target-async" of previous GDB versions.
797 * "set target-async" is deprecated as a CLI option and is now an alias
798 for "set mi-async" (only puts MI into async mode).
800 * Background execution commands (e.g., "c&", "s&", etc.) are now
801 possible ``out of the box'' if the target supports them. Previously
802 the user would need to explicitly enable the possibility with the
803 "set target-async on" command.
805 * New features in the GDB remote stub, GDBserver
807 ** New option --debug-format=option1[,option2,...] allows one to add
808 additional text to each output. At present only timestamps
809 are supported: --debug-format=timestamps.
810 Timestamps can also be turned on with the
811 "monitor set debug-format timestamps" command from GDB.
813 * The 'record instruction-history' command now starts counting instructions
814 at one. This also affects the instruction ranges reported by the
815 'record function-call-history' command when given the /i modifier.
817 * The command 'record function-call-history' supports a new modifier '/c' to
818 indent the function names based on their call stack depth.
819 The fields for the '/i' and '/l' modifier have been reordered.
820 The source line range is now prefixed with 'at'.
821 The instruction range is now prefixed with 'inst'.
822 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
823 "record instruction-history" and "list" commands.
825 * The ranges given as arguments to the 'record function-call-history' and
826 'record instruction-history' commands are now inclusive.
828 * The btrace record target now supports the 'record goto' command.
829 For locations inside the execution trace, the back trace is computed
830 based on the information stored in the execution trace.
832 * The btrace record target supports limited reverse execution and replay.
833 The target does not record data and therefore does not allow reading
836 * The "catch syscall" command now works on s390*-linux* targets.
838 * The "compare-sections" command is no longer specific to target
839 remote. It now works with all targets.
841 * All native targets are now consistently called "native".
842 Consequently, the "target child", "target GNU", "target djgpp",
843 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
844 commands have been replaced with "target native". The QNX/NTO port
845 leaves the "procfs" target in place and adds a "native" target for
846 consistency with other ports. The impact on users should be minimal
847 as these commands previously either throwed an error, or were
848 no-ops. The target's name is visible in the output of the following
849 commands: "help target", "info target", "info files", "maint print
852 * The "target native" command now connects to the native target. This
853 can be used to launch native programs even when "set
854 auto-connect-native-target" is set to off.
856 * GDB now supports access to Intel MPX registers on GNU/Linux.
858 * Support for Intel AVX-512 registers on GNU/Linux.
859 Support displaying and modifying Intel AVX-512 registers
860 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
864 qXfer:btrace:read's annex
865 The qXfer:btrace:read packet supports a new annex 'delta' to read
866 branch trace incrementally.
870 ** Valid Python operations on gdb.Value objects representing
871 structs/classes invoke the corresponding overloaded operators if
873 ** New `Xmethods' feature in the Python API. Xmethods are
874 additional methods or replacements for existing methods of a C++
875 class. This feature is useful for those cases where a method
876 defined in C++ source code could be inlined or optimized out by
877 the compiler, making it unavailable to GDB.
880 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
882 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
883 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
884 its alias "share", instead.
886 * The commands "set remotebaud" and "show remotebaud" are no longer
887 supported. Use "set serial baud" and "show serial baud" (respectively)
892 ** A new option "-gdb-set mi-async" replaces "-gdb-set
893 target-async". The latter is left as a deprecated alias of the
894 former for backward compatibility. If the target supports it,
895 CLI background execution commands are now always possible by
896 default, independently of whether the frontend stated a
897 preference for asynchronous execution with "-gdb-set mi-async".
898 Previously "-gdb-set target-async off" affected both MI execution
899 commands and CLI execution commands.
901 *** Changes in GDB 7.7
903 * Improved support for process record-replay and reverse debugging on
904 arm*-linux* targets. Support for thumb32 and syscall instruction
905 recording has been added.
907 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
909 * GDB now supports Fission DWP file format version 2.
910 http://gcc.gnu.org/wiki/DebugFission
912 * New convenience function "$_isvoid", to check whether an expression
913 is void. A void expression is an expression where the type of the
914 result is "void". For example, some convenience variables may be
915 "void" when evaluated (e.g., "$_exitcode" before the execution of
916 the program being debugged; or an undefined convenience variable).
917 Another example, when calling a function whose return type is
920 * The "maintenance print objfiles" command now takes an optional regexp.
922 * The "catch syscall" command now works on arm*-linux* targets.
924 * GDB now consistently shows "<not saved>" when printing values of
925 registers the debug info indicates have not been saved in the frame
926 and there's nowhere to retrieve them from
927 (callee-saved/call-clobbered registers):
932 (gdb) info registers rax
935 Before, the former would print "<optimized out>", and the latter
936 "*value not available*".
938 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
943 ** Frame filters and frame decorators have been added.
944 ** Temporary breakpoints are now supported.
945 ** Line tables representation has been added.
946 ** New attribute 'parent_type' for gdb.Field objects.
947 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
948 ** New attribute 'name' for gdb.Type objects.
952 Nios II ELF nios2*-*-elf
953 Nios II GNU/Linux nios2*-*-linux
954 Texas Instruments MSP430 msp430*-*-elf
956 * Removed native configurations
958 Support for these a.out NetBSD and OpenBSD obsolete configurations has
959 been removed. ELF variants of these configurations are kept supported.
961 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
962 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
963 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
964 i[34567]86-*-openbsd3.[0-3]
965 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
966 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
967 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
971 Like "catch throw", but catches a re-thrown exception.
973 Renamed from old "maint check-symtabs".
975 Perform consistency checks on symtabs.
977 Expand symtabs matching an optional regexp.
980 Display the details of GDB configure-time options.
982 maint set|show per-command
983 maint set|show per-command space
984 maint set|show per-command time
985 maint set|show per-command symtab
986 Enable display of per-command gdb resource usage.
988 remove-symbol-file FILENAME
989 remove-symbol-file -a ADDRESS
990 Remove a symbol file added via add-symbol-file. The file to remove
991 can be identified by its filename or by an address that lies within
992 the boundaries of this symbol file in memory.
995 info exceptions REGEXP
996 Display the list of Ada exceptions defined in the program being
997 debugged. If provided, only the exceptions whose names match REGEXP
1002 set debug symfile off|on
1004 Control display of debugging info regarding reading symbol files and
1005 symbol tables within those files
1007 set print raw frame-arguments
1008 show print raw frame-arguments
1009 Set/show whether to print frame arguments in raw mode,
1010 disregarding any defined pretty-printers.
1012 set remote trace-status-packet
1013 show remote trace-status-packet
1014 Set/show the use of remote protocol qTStatus packet.
1018 Control display of debugging messages related to Nios II targets.
1022 Control whether target-assisted range stepping is enabled.
1024 set startup-with-shell
1025 show startup-with-shell
1026 Specifies whether Unix child processes are started via a shell or
1031 Use the target memory cache for accesses to the code segment. This
1032 improves performance of remote debugging (particularly disassembly).
1034 * You can now use a literal value 'unlimited' for options that
1035 interpret 0 or -1 as meaning "unlimited". E.g., "set
1036 trace-buffer-size unlimited" is now an alias for "set
1037 trace-buffer-size -1" and "set height unlimited" is now an alias for
1040 * The "set debug symtab-create" debugging option of GDB has been changed to
1041 accept a verbosity level. 0 means "off", 1 provides basic debugging
1042 output, and values of 2 or greater provides more verbose output.
1044 * New command-line options
1046 Display the details of GDB configure-time options.
1048 * The command 'tsave' can now support new option '-ctf' to save trace
1049 buffer in Common Trace Format.
1051 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1054 * GDB now implements the the C++ 'typeid' operator.
1056 * The new convenience variable $_exception holds the exception being
1057 thrown or caught at an exception-related catchpoint.
1059 * The exception-related catchpoints, like "catch throw", now accept a
1060 regular expression which can be used to filter exceptions by type.
1062 * The new convenience variable $_exitsignal is automatically set to
1063 the terminating signal number when the program being debugged dies
1064 due to an uncaught signal.
1068 ** All MI commands now accept an optional "--language" option.
1069 Support for this feature can be verified by using the "-list-features"
1070 command, which should contain "language-option".
1072 ** The new command -info-gdb-mi-command allows the user to determine
1073 whether a GDB/MI command is supported or not.
1075 ** The "^error" result record returned when trying to execute an undefined
1076 GDB/MI command now provides a variable named "code" whose content is the
1077 "undefined-command" error code. Support for this feature can be verified
1078 by using the "-list-features" command, which should contain
1079 "undefined-command-error-code".
1081 ** The -trace-save MI command can optionally save trace buffer in Common
1084 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1086 ** The command -data-list-register-values now accepts an optional
1087 "--skip-unavailable" option. When used, only the available registers
1090 ** The new command -trace-frame-collected dumps collected variables,
1091 computed expressions, tvars, memory and registers in a traceframe.
1093 ** The commands -stack-list-locals, -stack-list-arguments and
1094 -stack-list-variables now accept an option "--skip-unavailable".
1095 When used, only the available locals or arguments are displayed.
1097 ** The -exec-run command now accepts an optional "--start" option.
1098 When used, the command follows the same semantics as the "start"
1099 command, stopping the program's execution at the start of its
1100 main subprogram. Support for this feature can be verified using
1101 the "-list-features" command, which should contain
1102 "exec-run-start-option".
1104 ** The new commands -catch-assert and -catch-exceptions insert
1105 catchpoints stopping the program when Ada exceptions are raised.
1107 ** The new command -info-ada-exceptions provides the equivalent of
1108 the new "info exceptions" command.
1110 * New system-wide configuration scripts
1111 A GDB installation now provides scripts suitable for use as system-wide
1112 configuration scripts for the following systems:
1116 * GDB now supports target-assigned range stepping with remote targets.
1117 This improves the performance of stepping source lines by reducing
1118 the number of control packets from/to GDB. See "New remote packets"
1121 * GDB now understands the element 'tvar' in the XML traceframe info.
1122 It has the id of the collected trace state variables.
1124 * On S/390 targets that provide the transactional-execution feature,
1125 the program interruption transaction diagnostic block (TDB) is now
1126 represented as a number of additional "registers" in GDB.
1128 * New remote packets
1132 The vCont packet supports a new 'r' action, that tells the remote
1133 stub to step through an address range itself, without GDB
1134 involvemement at each single-step.
1136 qXfer:libraries-svr4:read's annex
1137 The previously unused annex of the qXfer:libraries-svr4:read packet
1138 is now used to support passing an argument list. The remote stub
1139 reports support for this argument list to GDB's qSupported query.
1140 The defined arguments are "start" and "prev", used to reduce work
1141 necessary for library list updating, resulting in significant
1144 * New features in the GDB remote stub, GDBserver
1146 ** GDBserver now supports target-assisted range stepping. Currently
1147 enabled on x86/x86_64 GNU/Linux targets.
1149 ** GDBserver now adds element 'tvar' in the XML in the reply to
1150 'qXfer:traceframe-info:read'. It has the id of the collected
1151 trace state variables.
1153 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1156 * New 'z' formatter for printing and examining memory, this displays the
1157 value as hexadecimal zero padded on the left to the size of the type.
1159 * GDB can now use Windows x64 unwinding data.
1161 * The "set remotebaud" command has been replaced by "set serial baud".
1162 Similarly, "show remotebaud" has been replaced by "show serial baud".
1163 The "set remotebaud" and "show remotebaud" commands are still available
1164 to provide backward compatibility with older versions of GDB.
1166 *** Changes in GDB 7.6
1168 * Target record has been renamed to record-full.
1169 Record/replay is now enabled with the "record full" command.
1170 This also affects settings that are associated with full record/replay
1171 that have been moved from "set/show record" to "set/show record full":
1173 set|show record full insn-number-max
1174 set|show record full stop-at-limit
1175 set|show record full memory-query
1177 * A new record target "record-btrace" has been added. The new target
1178 uses hardware support to record the control-flow of a process. It
1179 does not support replaying the execution, but it implements the
1180 below new commands for investigating the recorded execution log.
1181 This new recording method can be enabled using:
1185 The "record-btrace" target is only available on Intel Atom processors
1186 and requires a Linux kernel 2.6.32 or later.
1188 * Two new commands have been added for record/replay to give information
1189 about the recorded execution without having to replay the execution.
1190 The commands are only supported by "record btrace".
1192 record instruction-history prints the execution history at
1193 instruction granularity
1195 record function-call-history prints the execution history at
1196 function granularity
1198 * New native configurations
1200 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1201 FreeBSD/powerpc powerpc*-*-freebsd
1202 x86_64/Cygwin x86_64-*-cygwin*
1203 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1207 ARM AArch64 aarch64*-*-elf
1208 ARM AArch64 GNU/Linux aarch64*-*-linux
1209 Lynx 178 PowerPC powerpc-*-lynx*178
1210 x86_64/Cygwin x86_64-*-cygwin*
1211 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1213 * If the configured location of system.gdbinit file (as given by the
1214 --with-system-gdbinit option at configure time) is in the
1215 data-directory (as specified by --with-gdb-datadir at configure
1216 time) or in one of its subdirectories, then GDB will look for the
1217 system-wide init file in the directory specified by the
1218 --data-directory command-line option.
1220 * New command line options:
1222 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1223 other initialization files, unlike -nx which disables all of them.
1225 * Removed command line options
1227 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1230 * The 'ptype' and 'whatis' commands now accept an argument to control
1233 * 'info proc' now works on some core files.
1237 ** Vectors can be created with gdb.Type.vector.
1239 ** Python's atexit.register now works in GDB.
1241 ** Types can be pretty-printed via a Python API.
1243 ** Python 3 is now supported (in addition to Python 2.4 or later)
1245 ** New class gdb.Architecture exposes GDB's internal representation
1246 of architecture in the Python API.
1248 ** New method Frame.architecture returns the gdb.Architecture object
1249 corresponding to the frame's architecture.
1251 * New Python-based convenience functions:
1253 ** $_memeq(buf1, buf2, length)
1254 ** $_streq(str1, str2)
1256 ** $_regex(str, regex)
1258 * The 'cd' command now defaults to using '~' (the home directory) if not
1261 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1262 default for GCC since November 2000.
1264 * The command 'forward-search' can now be abbreviated as 'fo'.
1266 * The command 'info tracepoints' can now display 'installed on target'
1267 or 'not installed on target' for each non-pending location of tracepoint.
1269 * New configure options
1271 --enable-libmcheck/--disable-libmcheck
1272 By default, development versions are built with -lmcheck on hosts
1273 that support it, in order to help track memory corruption issues.
1274 Release versions, on the other hand, are built without -lmcheck
1275 by default. The --enable-libmcheck/--disable-libmcheck configure
1276 options allow the user to override that default.
1277 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1278 This configure option allows the user to build GDB with
1279 libbabeltrace using which GDB can read Common Trace Format data.
1281 * New commands (for set/show, see "New options" below)
1284 Catch signals. This is similar to "handle", but allows commands and
1285 conditions to be attached.
1288 List the BFDs known to GDB.
1290 python-interactive [command]
1292 Start a Python interactive prompt, or evaluate the optional command
1293 and print the result of expressions.
1296 "py" is a new alias for "python".
1298 enable type-printer [name]...
1299 disable type-printer [name]...
1300 Enable or disable type printers.
1304 ** For the Renesas Super-H architecture, the "regs" command has been removed
1305 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1310 set print type methods (on|off)
1311 show print type methods
1312 Control whether method declarations are displayed by "ptype".
1313 The default is to show them.
1315 set print type typedefs (on|off)
1316 show print type typedefs
1317 Control whether typedef definitions are displayed by "ptype".
1318 The default is to show them.
1320 set filename-display basename|relative|absolute
1321 show filename-display
1322 Control the way in which filenames is displayed.
1323 The default is "relative", which preserves previous behavior.
1325 set trace-buffer-size
1326 show trace-buffer-size
1327 Request target to change the size of trace buffer.
1329 set remote trace-buffer-size-packet auto|on|off
1330 show remote trace-buffer-size-packet
1331 Control the use of the remote protocol `QTBuffer:size' packet.
1335 Control display of debugging messages related to ARM AArch64.
1338 set debug coff-pe-read
1339 show debug coff-pe-read
1340 Control display of debugging messages related to reading of COFF/PE
1345 Control display of debugging messages related to Mach-O symbols
1348 set debug notification
1349 show debug notification
1350 Control display of debugging info for async remote notification.
1354 ** Command parameter changes are now notified using new async record
1355 "=cmd-param-changed".
1356 ** Trace frame changes caused by command "tfind" are now notified using
1357 new async record "=traceframe-changed".
1358 ** The creation, deletion and modification of trace state variables
1359 are now notified using new async records "=tsv-created",
1360 "=tsv-deleted" and "=tsv-modified".
1361 ** The start and stop of process record are now notified using new
1362 async record "=record-started" and "=record-stopped".
1363 ** Memory changes are now notified using new async record
1365 ** The data-disassemble command response will include a "fullname" field
1366 containing the absolute file name when source has been requested.
1367 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1368 command, to allow pattern filling of memory areas.
1369 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1370 library load/unload events.
1371 ** The response to breakpoint commands and breakpoint async records
1372 includes an "installed" field containing a boolean state about each
1373 non-pending tracepoint location is whether installed on target or not.
1374 ** Output of the "-trace-status" command includes a "trace-file" field
1375 containing the name of the trace file being examined. This field is
1376 optional, and only present when examining a trace file.
1377 ** The "fullname" field is now always present along with the "file" field,
1378 even if the file cannot be found by GDB.
1380 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1381 You must have the LZMA library available when configuring GDB for this
1382 feature to be enabled. For more information, see:
1383 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1385 * New remote packets
1388 Set the size of trace buffer. The remote stub reports support for this
1389 packet to gdb's qSupported query.
1392 Enable Branch Trace Store (BTS)-based branch tracing for the current
1393 thread. The remote stub reports support for this packet to gdb's
1397 Disable branch tracing for the current thread. The remote stub reports
1398 support for this packet to gdb's qSupported query.
1401 Read the traced branches for the current thread. The remote stub
1402 reports support for this packet to gdb's qSupported query.
1404 *** Changes in GDB 7.5
1406 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1407 for more x32 ABI info.
1409 * GDB now supports access to MIPS DSP registers on Linux targets.
1411 * GDB now supports debugging microMIPS binaries.
1413 * The "info os" command on GNU/Linux can now display information on
1414 several new classes of objects managed by the operating system:
1415 "info os procgroups" lists process groups
1416 "info os files" lists file descriptors
1417 "info os sockets" lists internet-domain sockets
1418 "info os shm" lists shared-memory regions
1419 "info os semaphores" lists semaphores
1420 "info os msg" lists message queues
1421 "info os modules" lists loaded kernel modules
1423 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1424 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1425 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1426 options and inspect the probe arguments using the new $_probe_arg family
1427 of convenience variables. You can obtain more information about SystemTap
1428 in <http://sourceware.org/systemtap/>.
1430 * GDB now supports reversible debugging on ARM, it allows you to
1431 debug basic ARM and THUMB instructions, and provides
1432 record/replay support.
1434 * The option "symbol-reloading" has been deleted as it is no longer used.
1438 ** GDB commands implemented in Python can now be put in command class
1441 ** The "maint set python print-stack on|off" is now deleted.
1443 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1444 apply "flag enum"-style pretty-printing to any enum.
1446 ** gdb.lookup_symbol can now work when there is no current frame.
1448 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1449 the source at which the symbol was defined.
1451 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1452 method 'value'. The former indicates whether the symbol needs a
1453 frame in order to compute its value, and the latter computes the
1456 ** A new method 'referenced_value' on gdb.Value objects which can
1457 dereference pointer as well as C++ reference values.
1459 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1460 which return the global and static blocks (as gdb.Block objects),
1461 of the underlying symbol table, respectively.
1463 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1464 object associated with a PC value.
1466 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1467 of the address range occupied by code for the current source line.
1469 * Go language support.
1470 GDB now supports debugging programs written in the Go programming
1473 * GDBserver now supports stdio connections.
1474 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1476 * The binary "gdbtui" can no longer be built or installed.
1477 Use "gdb -tui" instead.
1479 * GDB will now print "flag" enums specially. A flag enum is one where
1480 all the enumerator values have no bits in common when pairwise
1481 "and"ed. When printing a value whose type is a flag enum, GDB will
1482 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1483 (gdb) print (enum E) 3
1486 * The filename part of a linespec will now match trailing components
1487 of a source file name. For example, "break gcc/expr.c:1000" will
1488 now set a breakpoint in build/gcc/expr.c, but not
1489 build/libcpp/expr.c.
1491 * The "info proc" and "generate-core-file" commands will now also
1492 work on remote targets connected to GDBserver on Linux.
1494 * The command "info catch" has been removed. It has been disabled
1495 since December 2007.
1497 * The "catch exception" and "catch assert" commands now accept
1498 a condition at the end of the command, much like the "break"
1499 command does. For instance:
1501 (gdb) catch exception Constraint_Error if Barrier = True
1503 Previously, it was possible to add a condition to such catchpoints,
1504 but it had to be done as a second step, after the catchpoint had been
1505 created, using the "condition" command.
1507 * The "info static-tracepoint-marker" command will now also work on
1508 native Linux targets with in-process agent.
1510 * GDB can now set breakpoints on inlined functions.
1512 * The .gdb_index section has been updated to include symbols for
1513 inlined functions. GDB will ignore older .gdb_index sections by
1514 default, which could cause symbol files to be loaded more slowly
1515 until their .gdb_index sections can be recreated. The new command
1516 "set use-deprecated-index-sections on" will cause GDB to use any older
1517 .gdb_index sections it finds. This will restore performance, but the
1518 ability to set breakpoints on inlined functions will be lost in symbol
1519 files with older .gdb_index sections.
1521 The .gdb_index section has also been updated to record more information
1522 about each symbol. This speeds up the "info variables", "info functions"
1523 and "info types" commands when used with programs having the .gdb_index
1524 section, as well as speeding up debugging with shared libraries using
1525 the .gdb_index section.
1527 * Ada support for GDB/MI Variable Objects has been added.
1529 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1534 ** New command -info-os is the MI equivalent of "info os".
1536 ** Output logs ("set logging" and related) now include MI output.
1540 ** "set use-deprecated-index-sections on|off"
1541 "show use-deprecated-index-sections on|off"
1542 Controls the use of deprecated .gdb_index sections.
1544 ** "catch load" and "catch unload" can be used to stop when a shared
1545 library is loaded or unloaded, respectively.
1547 ** "enable count" can be used to auto-disable a breakpoint after
1550 ** "info vtbl" can be used to show the virtual method tables for
1551 C++ and Java objects.
1553 ** "explore" and its sub commands "explore value" and "explore type"
1554 can be used to recursively explore values and types of
1555 expressions. These commands are available only if GDB is
1556 configured with '--with-python'.
1558 ** "info auto-load" shows status of all kinds of auto-loaded files,
1559 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1560 sequences of commands files, "info auto-load python-scripts"
1561 shows status of auto-loading Python script files,
1562 "info auto-load local-gdbinit" shows status of loading init file
1563 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1564 status of inferior specific thread debugging shared library loading.
1566 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1567 and "show auto-load-scripts" commands have been deprecated, use their
1568 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1569 and "show auto-load python-scripts" counterparts instead.
1571 ** "dprintf location,format,args..." creates a dynamic printf, which
1572 is basically a breakpoint that does a printf and immediately
1573 resumes your program's execution, so it is like a printf that you
1574 can insert dynamically at runtime instead of at compiletime.
1576 ** "set print symbol"
1578 Controls whether GDB attempts to display the symbol, if any,
1579 corresponding to addresses it prints. This defaults to "on", but
1580 you can set it to "off" to restore GDB's previous behavior.
1582 * Deprecated commands
1584 ** For the Renesas Super-H architecture, the "regs" command has been
1585 deprecated, and "info all-registers" should be used instead.
1589 Renesas RL78 rl78-*-elf
1590 HP OpenVMS ia64 ia64-hp-openvms*
1592 * GDBserver supports evaluation of breakpoint conditions. When
1593 support is advertised by GDBserver, GDB may be told to send the
1594 breakpoint conditions in bytecode form to GDBserver. GDBserver
1595 will only report the breakpoint trigger to GDB when its condition
1600 set mips compression
1601 show mips compression
1602 Select the compressed ISA encoding used in functions that have no symbol
1603 information available. The encoding can be set to either of:
1606 and is updated automatically from ELF file flags if available.
1608 set breakpoint condition-evaluation
1609 show breakpoint condition-evaluation
1610 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1611 GDBserver ("target"). Default option "auto" chooses the most efficient
1613 This option can improve debugger efficiency depending on the speed of the
1617 Disable auto-loading globally.
1620 Show auto-loading setting of all kinds of auto-loaded files.
1622 set auto-load gdb-scripts on|off
1623 show auto-load gdb-scripts
1624 Control auto-loading of GDB canned sequences of commands files.
1626 set auto-load python-scripts on|off
1627 show auto-load python-scripts
1628 Control auto-loading of Python script files.
1630 set auto-load local-gdbinit on|off
1631 show auto-load local-gdbinit
1632 Control loading of init file (.gdbinit) from current directory.
1634 set auto-load libthread-db on|off
1635 show auto-load libthread-db
1636 Control auto-loading of inferior specific thread debugging shared library.
1638 set auto-load scripts-directory <dir1>[:<dir2>...]
1639 show auto-load scripts-directory
1640 Set a list of directories from which to load auto-loaded scripts.
1641 Automatically loaded Python scripts and GDB scripts are located in one
1642 of the directories listed by this option.
1643 The delimiter (':' above) may differ according to the host platform.
1645 set auto-load safe-path <dir1>[:<dir2>...]
1646 show auto-load safe-path
1647 Set a list of directories from which it is safe to auto-load files.
1648 The delimiter (':' above) may differ according to the host platform.
1650 set debug auto-load on|off
1651 show debug auto-load
1652 Control display of debugging info for auto-loading the files above.
1654 set dprintf-style gdb|call|agent
1656 Control the way in which a dynamic printf is performed; "gdb"
1657 requests a GDB printf command, while "call" causes dprintf to call a
1658 function in the inferior. "agent" requests that the target agent
1659 (such as GDBserver) do the printing.
1661 set dprintf-function <expr>
1662 show dprintf-function
1663 set dprintf-channel <expr>
1664 show dprintf-channel
1665 Set the function and optional first argument to the call when using
1666 the "call" style of dynamic printf.
1668 set disconnected-dprintf on|off
1669 show disconnected-dprintf
1670 Control whether agent-style dynamic printfs continue to be in effect
1671 after GDB disconnects.
1673 * New configure options
1675 --with-auto-load-dir
1676 Configure default value for the 'set auto-load scripts-directory'
1677 setting above. It defaults to '$debugdir:$datadir/auto-load',
1678 $debugdir representing global debugging info directories (available
1679 via 'show debug-file-directory') and $datadir representing GDB's data
1680 directory (available via 'show data-directory').
1682 --with-auto-load-safe-path
1683 Configure default value for the 'set auto-load safe-path' setting
1684 above. It defaults to the --with-auto-load-dir setting.
1686 --without-auto-load-safe-path
1687 Set 'set auto-load safe-path' to '/', effectively disabling this
1690 * New remote packets
1692 z0/z1 conditional breakpoints extension
1694 The z0/z1 breakpoint insertion packets have been extended to carry
1695 a list of conditional expressions over to the remote stub depending on the
1696 condition evaluation mode. The use of this extension can be controlled
1697 via the "set remote conditional-breakpoints-packet" command.
1701 Specify the signals which the remote stub may pass to the debugged
1702 program without GDB involvement.
1704 * New command line options
1706 --init-command=FILE, -ix Like --command, -x but execute it
1707 before loading inferior.
1708 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1709 execute it before loading inferior.
1711 *** Changes in GDB 7.4
1713 * GDB now handles ambiguous linespecs more consistently; the existing
1714 FILE:LINE support has been expanded to other types of linespecs. A
1715 breakpoint will now be set on all matching locations in all
1716 inferiors, and locations will be added or removed according to
1719 * GDB now allows you to skip uninteresting functions and files when
1720 stepping with the "skip function" and "skip file" commands.
1722 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1723 and "show remote hardware-watchpoint-length-limit". These allows to
1724 set or show the maximum length limit (in bytes) of a remote
1725 target hardware watchpoint.
1727 This allows e.g. to use "unlimited" hardware watchpoints with the
1728 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1729 watchpoints are slower than real hardware watchpoints but are
1730 significantly faster than gdb software watchpoints.
1734 ** The register_pretty_printer function in module gdb.printing now takes
1735 an optional `replace' argument. If True, the new printer replaces any
1738 ** The "maint set python print-stack on|off" command has been
1739 deprecated and will be deleted in GDB 7.5.
1740 A new command: "set python print-stack none|full|message" has
1741 replaced it. Additionally, the default for "print-stack" is
1742 now "message", which just prints the error message without
1745 ** A prompt substitution hook (prompt_hook) is now available to the
1748 ** A new Python module, gdb.prompt has been added to the GDB Python
1749 modules library. This module provides functionality for
1750 escape sequences in prompts (used by set/show
1751 extended-prompt). These escape sequences are replaced by their
1752 corresponding value.
1754 ** Python commands and convenience-functions located in
1755 'data-directory'/python/gdb/command and
1756 'data-directory'/python/gdb/function are now automatically loaded
1759 ** Blocks now provide four new attributes. global_block and
1760 static_block will return the global and static blocks
1761 respectively. is_static and is_global are boolean attributes
1762 that indicate if the block is one of those two types.
1764 ** Symbols now provide the "type" attribute, the type of the symbol.
1766 ** The "gdb.breakpoint" function has been deprecated in favor of
1769 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1770 of a function. This class is based on the "finish" command
1771 available in the CLI.
1773 ** Type objects for struct and union types now allow access to
1774 the fields using standard Python dictionary (mapping) methods.
1775 For example, "some_type['myfield']" now works, as does
1776 "some_type.items()".
1778 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1781 ** A new function, "deep_items" has been added to the gdb.types
1782 module in the GDB Python modules library. This function returns
1783 an iterator over the fields of a struct or union type. Unlike
1784 the standard Python "iteritems" method, it will recursively traverse
1785 any anonymous fields.
1789 ** "*stopped" events can report several new "reason"s, such as
1792 ** Breakpoint changes are now notified using new async records, like
1793 "=breakpoint-modified".
1795 ** New command -ada-task-info.
1797 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1798 $sdir specifies the default system locations of shared libraries.
1799 $pdir specifies the directory where the libpthread used by the application
1802 GDB no longer looks in $sdir and $pdir after it has searched the directories
1803 mentioned in libthread-db-search-path. If you want to search those
1804 directories, they must be specified in libthread-db-search-path.
1805 The default value of libthread-db-search-path on GNU/Linux and Solaris
1806 systems is now "$sdir:$pdir".
1808 $pdir is not supported by gdbserver, it is currently ignored.
1809 $sdir is supported by gdbserver.
1811 * New configure option --with-iconv-bin.
1812 When using the internationalization support like the one in the GNU C
1813 library, GDB will invoke the "iconv" program to get a list of supported
1814 character sets. If this program lives in a non-standard location, one can
1815 use this option to specify where to find it.
1817 * When natively debugging programs on PowerPC BookE processors running
1818 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1819 watchpoints, which specify a mask in addition to an address to watch.
1820 The mask specifies that some bits of an address (the bits which are
1821 reset in the mask) should be ignored when matching the address accessed
1822 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1823 section in the user manual for more details.
1825 * The new option --once causes GDBserver to stop listening for connections once
1826 the first connection is made. The listening port used by GDBserver will
1827 become available after that.
1829 * New commands "info macros" and "alias" have been added.
1831 * New function parameters suffix @entry specifies value of function parameter
1832 at the time the function got called. Entry values are available only since
1838 "!" is now an alias of the "shell" command.
1839 Note that no space is needed between "!" and SHELL COMMAND.
1843 watch EXPRESSION mask MASK_VALUE
1844 The watch command now supports the mask argument which allows creation
1845 of masked watchpoints, if the current architecture supports this feature.
1847 info auto-load-scripts [REGEXP]
1848 This command was formerly named "maintenance print section-scripts".
1849 It is now generally useful and is no longer a maintenance-only command.
1851 info macro [-all] [--] MACRO
1852 The info macro command has new options `-all' and `--'. The first for
1853 printing all definitions of a macro. The second for explicitly specifying
1854 the end of arguments and the beginning of the macro name in case the macro
1855 name starts with a hyphen.
1857 collect[/s] EXPRESSIONS
1858 The tracepoint collect command now takes an optional modifier "/s"
1859 that directs it to dereference pointer-to-character types and
1860 collect the bytes of memory up to a zero byte. The behavior is
1861 similar to what you see when you use the regular print command on a
1862 string. An optional integer following the "/s" sets a bound on the
1863 number of bytes that will be collected.
1866 The trace start command now interprets any supplied arguments as a
1867 note to be recorded with the trace run, with an effect similar to
1868 setting the variable trace-notes.
1871 The trace stop command now interprets any arguments as a note to be
1872 mentioned along with the tstatus report that the trace was stopped
1873 with a command. The effect is similar to setting the variable
1876 * Tracepoints can now be enabled and disabled at any time after a trace
1877 experiment has been started using the standard "enable" and "disable"
1878 commands. It is now possible to start a trace experiment with no enabled
1879 tracepoints; GDB will display a warning, but will allow the experiment to
1880 begin, assuming that tracepoints will be enabled as needed while the trace
1883 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1884 locations with 4-byte instructions, when they were previously
1885 limited to locations with instructions of 5 bytes or longer.
1889 set debug dwarf2-read
1890 show debug dwarf2-read
1891 Turns on or off display of debugging messages related to reading
1892 DWARF debug info. The default is off.
1894 set debug symtab-create
1895 show debug symtab-create
1896 Turns on or off display of debugging messages related to symbol table
1897 creation. The default is off.
1900 show extended-prompt
1901 Set the GDB prompt, and allow escape sequences to be inserted to
1902 display miscellaneous information (see 'help set extended-prompt'
1903 for the list of sequences). This prompt (and any information
1904 accessed through the escape sequences) is updated every time the
1905 prompt is displayed.
1907 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1908 show print entry-values
1909 Set printing of frame argument values at function entry. In some cases
1910 GDB can determine the value of function argument which was passed by the
1911 function caller, even if the value was modified inside the called function.
1913 set debug entry-values
1914 show debug entry-values
1915 Control display of debugging info for determining frame argument values at
1916 function entry and virtual tail call frames.
1918 set basenames-may-differ
1919 show basenames-may-differ
1920 Set whether a source file may have multiple base names.
1921 (A "base name" is the name of a file with the directory part removed.
1922 Example: The base name of "/home/user/hello.c" is "hello.c".)
1923 If set, GDB will canonicalize file names (e.g., expand symlinks)
1924 before comparing them. Canonicalization is an expensive operation,
1925 but it allows the same file be known by more than one base name.
1926 If not set (the default), all source files are assumed to have just
1927 one base name, and gdb will do file name comparisons more efficiently.
1933 Set a user name and notes for the current and any future trace runs.
1934 This is useful for long-running and/or disconnected traces, to
1935 inform others (or yourself) as to who is running the trace, supply
1936 contact information, or otherwise explain what is going on.
1938 set trace-stop-notes
1939 show trace-stop-notes
1940 Set a note attached to the trace run, that is displayed when the
1941 trace has been stopped by a tstop command. This is useful for
1942 instance as an explanation, if you are stopping a trace run that was
1943 started by someone else.
1945 * New remote packets
1949 Dynamically enable a tracepoint in a started trace experiment.
1953 Dynamically disable a tracepoint in a started trace experiment.
1957 Set the user and notes of the trace run.
1961 Query the current status of a tracepoint.
1965 Query the minimum length of instruction at which a fast tracepoint may
1968 * Dcache size (number of lines) and line-size are now runtime-configurable
1969 via "set dcache line" and "set dcache line-size" commands.
1973 Texas Instruments TMS320C6x tic6x-*-*
1977 Renesas RL78 rl78-*-elf
1979 *** Changes in GDB 7.3.1
1981 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1983 *** Changes in GDB 7.3
1985 * GDB has a new command: "thread find [REGEXP]".
1986 It finds the thread id whose name, target id, or thread extra info
1987 matches the given regular expression.
1989 * The "catch syscall" command now works on mips*-linux* targets.
1991 * The -data-disassemble MI command now supports modes 2 and 3 for
1992 dumping the instruction opcodes.
1994 * New command line options
1996 -data-directory DIR Specify DIR as the "data-directory".
1997 This is mostly for testing purposes.
1999 * The "maint set python auto-load on|off" command has been renamed to
2000 "set auto-load-scripts on|off".
2002 * GDB has a new command: "set directories".
2003 It is like the "dir" command except that it replaces the
2004 source path list instead of augmenting it.
2006 * GDB now understands thread names.
2008 On GNU/Linux, "info threads" will display the thread name as set by
2009 prctl or pthread_setname_np.
2011 There is also a new command, "thread name", which can be used to
2012 assign a name internally for GDB to display.
2015 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2016 has been integrated into GDB.
2020 ** The function gdb.Write now accepts an optional keyword 'stream'.
2021 This keyword, when provided, will direct the output to either
2022 stdout, stderr, or GDB's logging output.
2024 ** Parameters can now be be sub-classed in Python, and in particular
2025 you may implement the get_set_doc and get_show_doc functions.
2026 This improves how Parameter set/show documentation is processed
2027 and allows for more dynamic content.
2029 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2030 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2031 have an is_valid method.
2033 ** Breakpoints can now be sub-classed in Python, and in particular
2034 you may implement a 'stop' function that is executed each time
2035 the inferior reaches that breakpoint.
2037 ** New function gdb.lookup_global_symbol looks up a global symbol.
2039 ** GDB values in Python are now callable if the value represents a
2040 function. For example, if 'some_value' represents a function that
2041 takes two integer parameters and returns a value, you can call
2042 that function like so:
2044 result = some_value (10,20)
2046 ** Module gdb.types has been added.
2047 It contains a collection of utilities for working with gdb.Types objects:
2048 get_basic_type, has_field, make_enum_dict.
2050 ** Module gdb.printing has been added.
2051 It contains utilities for writing and registering pretty-printers.
2052 New classes: PrettyPrinter, SubPrettyPrinter,
2053 RegexpCollectionPrettyPrinter.
2054 New function: register_pretty_printer.
2056 ** New commands "info pretty-printers", "enable pretty-printer" and
2057 "disable pretty-printer" have been added.
2059 ** gdb.parameter("directories") is now available.
2061 ** New function gdb.newest_frame returns the newest frame in the
2064 ** The gdb.InferiorThread class has a new "name" attribute. This
2065 holds the thread's name.
2067 ** Python Support for Inferior events.
2068 Python scripts can add observers to be notified of events
2069 occurring in the process being debugged.
2070 The following events are currently supported:
2071 - gdb.events.cont Continue event.
2072 - gdb.events.exited Inferior exited event.
2073 - gdb.events.stop Signal received, and Breakpoint hit events.
2077 ** GDB now puts template parameters in scope when debugging in an
2078 instantiation. For example, if you have:
2080 template<int X> int func (void) { return X; }
2082 then if you step into func<5>, "print X" will show "5". This
2083 feature requires proper debuginfo support from the compiler; it
2084 was added to GCC 4.5.
2086 ** The motion commands "next", "finish", "until", and "advance" now
2087 work better when exceptions are thrown. In particular, GDB will
2088 no longer lose control of the inferior; instead, the GDB will
2089 stop the inferior at the point at which the exception is caught.
2090 This functionality requires a change in the exception handling
2091 code that was introduced in GCC 4.5.
2093 * GDB now follows GCC's rules on accessing volatile objects when
2094 reading or writing target state during expression evaluation.
2095 One notable difference to prior behavior is that "print x = 0"
2096 no longer generates a read of x; the value of the assignment is
2097 now always taken directly from the value being assigned.
2099 * GDB now has some support for using labels in the program's source in
2100 linespecs. For instance, you can use "advance label" to continue
2101 execution to a label.
2103 * GDB now has support for reading and writing a new .gdb_index
2104 section. This section holds a fast index of DWARF debugging
2105 information and can be used to greatly speed up GDB startup and
2106 operation. See the documentation for `save gdb-index' for details.
2108 * The "watch" command now accepts an optional "-location" argument.
2109 When used, this causes GDB to watch the memory referred to by the
2110 expression. Such a watchpoint is never deleted due to it going out
2113 * GDB now supports thread debugging of core dumps on GNU/Linux.
2115 GDB now activates thread debugging using the libthread_db library
2116 when debugging GNU/Linux core dumps, similarly to when debugging
2117 live processes. As a result, when debugging a core dump file, GDB
2118 is now able to display pthread_t ids of threads. For example, "info
2119 threads" shows the same output as when debugging the process when it
2120 was live. In earlier releases, you'd see something like this:
2123 * 1 LWP 6780 main () at main.c:10
2125 While now you see this:
2128 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2130 It is also now possible to inspect TLS variables when debugging core
2133 When debugging a core dump generated on a machine other than the one
2134 used to run GDB, you may need to point GDB at the correct
2135 libthread_db library with the "set libthread-db-search-path"
2136 command. See the user manual for more details on this command.
2138 * When natively debugging programs on PowerPC BookE processors running
2139 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2140 which stop execution of the inferior whenever it executes an instruction
2141 at any address within the specified range. See the "PowerPC Embedded"
2142 section in the user manual for more details.
2144 * New features in the GDB remote stub, GDBserver
2146 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2147 and i686 LynxOS (version 5.x).
2149 ** GDBserver is now supported on Blackfin Linux.
2151 * New native configurations
2153 ia64 HP-UX ia64-*-hpux*
2157 Analog Devices, Inc. Blackfin Processor bfin-*
2159 * Ada task switching is now supported on sparc-elf targets when
2160 debugging a program using the Ravenscar Profile. For more information,
2161 see the "Tasking Support when using the Ravenscar Profile" section
2162 in the GDB user manual.
2164 * Guile support was removed.
2166 * New features in the GNU simulator
2168 ** The --map-info flag lists all known core mappings.
2170 ** CFI flashes may be simulated via the "cfi" device.
2172 *** Changes in GDB 7.2
2174 * Shared library support for remote targets by default
2176 When GDB is configured for a generic, non-OS specific target, like
2177 for example, --target=arm-eabi or one of the many *-*-elf targets,
2178 GDB now queries remote stubs for loaded shared libraries using the
2179 `qXfer:libraries:read' packet. Previously, shared library support
2180 was always disabled for such configurations.
2184 ** Argument Dependent Lookup (ADL)
2186 In C++ ADL lookup directs function search to the namespaces of its
2187 arguments even if the namespace has not been imported.
2197 Here the compiler will search for `foo' in the namespace of 'b'
2198 and find A::foo. GDB now supports this. This construct is commonly
2199 used in the Standard Template Library for operators.
2201 ** Improved User Defined Operator Support
2203 In addition to member operators, GDB now supports lookup of operators
2204 defined in a namespace and imported with a `using' directive, operators
2205 defined in the global scope, operators imported implicitly from an
2206 anonymous namespace, and the ADL operators mentioned in the previous
2208 GDB now also supports proper overload resolution for all the previously
2209 mentioned flavors of operators.
2211 ** static const class members
2213 Printing of static const class members that are initialized in the
2214 class definition has been fixed.
2216 * Windows Thread Information Block access.
2218 On Windows targets, GDB now supports displaying the Windows Thread
2219 Information Block (TIB) structure. This structure is visible either
2220 by using the new command `info w32 thread-information-block' or, by
2221 dereferencing the new convenience variable named `$_tlb', a
2222 thread-specific pointer to the TIB. This feature is also supported
2223 when remote debugging using GDBserver.
2225 * Static tracepoints
2227 Static tracepoints are calls in the user program into a tracing
2228 library. One such library is a port of the LTTng kernel tracer to
2229 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2230 When debugging with GDBserver, GDB now supports combining the GDB
2231 tracepoint machinery with such libraries. For example: the user can
2232 use GDB to probe a static tracepoint marker (a call from the user
2233 program into the tracing library) with the new "strace" command (see
2234 "New commands" below). This creates a "static tracepoint" in the
2235 breakpoint list, that can be manipulated with the same feature set
2236 as fast and regular tracepoints. E.g., collect registers, local and
2237 global variables, collect trace state variables, and define
2238 tracepoint conditions. In addition, the user can collect extra
2239 static tracepoint marker specific data, by collecting the new
2240 $_sdata internal variable. When analyzing the trace buffer, you can
2241 inspect $_sdata like any other variable available to GDB. For more
2242 information, see the "Tracepoints" chapter in GDB user manual. New
2243 remote packets have been defined to support static tracepoints, see
2244 the "New remote packets" section below.
2246 * Better reconstruction of tracepoints after disconnected tracing
2248 GDB will attempt to download the original source form of tracepoint
2249 definitions when starting a trace run, and then will upload these
2250 upon reconnection to the target, resulting in a more accurate
2251 reconstruction of the tracepoints that are in use on the target.
2255 You can now exercise direct control over the ways that GDB can
2256 affect your program. For instance, you can disallow the setting of
2257 breakpoints, so that the program can run continuously (assuming
2258 non-stop mode). In addition, the "observer" variable is available
2259 to switch all of the different controls; in observer mode, GDB
2260 cannot affect the target's behavior at all, which is useful for
2261 tasks like diagnosing live systems in the field.
2263 * The new convenience variable $_thread holds the number of the
2266 * New remote packets
2270 Return the address of the Windows Thread Information Block of a given thread.
2274 In response to several of the tracepoint packets, the target may now
2275 also respond with a number of intermediate `qRelocInsn' request
2276 packets before the final result packet, to have GDB handle
2277 relocating an instruction to execute at a different address. This
2278 is particularly useful for stubs that support fast tracepoints. GDB
2279 reports support for this feature in the qSupported packet.
2283 List static tracepoint markers in the target program.
2287 List static tracepoint markers at a given address in the target
2290 qXfer:statictrace:read
2292 Read the static trace data collected (by a `collect $_sdata'
2293 tracepoint action). The remote stub reports support for this packet
2294 to gdb's qSupported query.
2298 Send the current settings of GDB's permission flags.
2302 Send part of the source (textual) form of a tracepoint definition,
2303 which includes location, conditional, and action list.
2305 * The source command now accepts a -s option to force searching for the
2306 script in the source search path even if the script name specifies
2309 * New features in the GDB remote stub, GDBserver
2311 - GDBserver now support tracepoints (including fast tracepoints, and
2312 static tracepoints). The feature is currently supported by the
2313 i386-linux and amd64-linux builds. See the "Tracepoints support
2314 in gdbserver" section in the manual for more information.
2316 GDBserver JIT compiles the tracepoint's conditional agent
2317 expression bytecode into native code whenever possible for low
2318 overhead dynamic tracepoints conditionals. For such tracepoints,
2319 an expression that examines program state is evaluated when the
2320 tracepoint is reached, in order to determine whether to capture
2321 trace data. If the condition is simple and false, processing the
2322 tracepoint finishes very quickly and no data is gathered.
2324 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2325 for static tracepoints support.
2327 - GDBserver now supports x86_64 Windows 64-bit debugging.
2329 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2330 it understands register description.
2332 * The --batch flag now disables pagination and queries.
2334 * X86 general purpose registers
2336 GDB now supports reading/writing byte, word and double-word x86
2337 general purpose registers directly. This means you can use, say,
2338 $ah or $ax to refer, respectively, to the byte register AH and
2339 16-bit word register AX that are actually portions of the 32-bit
2340 register EAX or 64-bit register RAX.
2342 * The `commands' command now accepts a range of breakpoints to modify.
2343 A plain `commands' following a command that creates multiple
2344 breakpoints affects all the breakpoints set by that command. This
2345 applies to breakpoints set by `rbreak', and also applies when a
2346 single `break' command creates multiple breakpoints (e.g.,
2347 breakpoints on overloaded c++ functions).
2349 * The `rbreak' command now accepts a filename specification as part of
2350 its argument, limiting the functions selected by the regex to those
2351 in the specified file.
2353 * Support for remote debugging Windows and SymbianOS shared libraries
2354 from Unix hosts has been improved. Non Windows GDB builds now can
2355 understand target reported file names that follow MS-DOS based file
2356 system semantics, such as file names that include drive letters and
2357 use the backslash character as directory separator. This makes it
2358 possible to transparently use the "set sysroot" and "set
2359 solib-search-path" on Unix hosts to point as host copies of the
2360 target's shared libraries. See the new command "set
2361 target-file-system-kind" described below, and the "Commands to
2362 specify files" section in the user manual for more information.
2366 eval template, expressions...
2367 Convert the values of one or more expressions under the control
2368 of the string template to a command line, and call it.
2370 set target-file-system-kind unix|dos-based|auto
2371 show target-file-system-kind
2372 Set or show the assumed file system kind for target reported file
2375 save breakpoints <filename>
2376 Save all current breakpoint definitions to a file suitable for use
2377 in a later debugging session. To read the saved breakpoint
2378 definitions, use the `source' command.
2380 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2383 info static-tracepoint-markers
2384 Display information about static tracepoint markers in the target.
2386 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2387 Define a static tracepoint by probing a marker at the given
2388 function, line, address, or marker ID.
2392 Enable and disable observer mode.
2394 set may-write-registers on|off
2395 set may-write-memory on|off
2396 set may-insert-breakpoints on|off
2397 set may-insert-tracepoints on|off
2398 set may-insert-fast-tracepoints on|off
2399 set may-interrupt on|off
2400 Set individual permissions for GDB effects on the target. Note that
2401 some of these settings can have undesirable or surprising
2402 consequences, particularly when changed in the middle of a session.
2403 For instance, disabling the writing of memory can prevent
2404 breakpoints from being inserted, cause single-stepping to fail, or
2405 even crash your program, if you disable after breakpoints have been
2406 inserted. However, GDB should not crash.
2408 set record memory-query on|off
2409 show record memory-query
2410 Control whether to stop the inferior if memory changes caused
2411 by an instruction cannot be recorded.
2416 The disassemble command now supports "start,+length" form of two arguments.
2420 ** GDB now provides a new directory location, called the python directory,
2421 where Python scripts written for GDB can be installed. The location
2422 of that directory is <data-directory>/python, where <data-directory>
2423 is the GDB data directory. For more details, see section `Scripting
2424 GDB using Python' in the manual.
2426 ** The GDB Python API now has access to breakpoints, symbols, symbol
2427 tables, program spaces, inferiors, threads and frame's code blocks.
2428 Additionally, GDB Parameters can now be created from the API, and
2429 manipulated via set/show in the CLI.
2431 ** New functions gdb.target_charset, gdb.target_wide_charset,
2432 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2434 ** New exception gdb.GdbError.
2436 ** Pretty-printers are now also looked up in the current program space.
2438 ** Pretty-printers can now be individually enabled and disabled.
2440 ** GDB now looks for names of Python scripts to auto-load in a
2441 special section named `.debug_gdb_scripts', in addition to looking
2442 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2444 * Tracepoint actions were unified with breakpoint commands. In particular,
2445 there are no longer differences in "info break" output for breakpoints and
2446 tracepoints and the "commands" command can be used for both tracepoints and
2447 regular breakpoints.
2451 ARM Symbian arm*-*-symbianelf*
2453 * D language support.
2454 GDB now supports debugging programs written in the D programming
2457 * GDB now supports the extended ptrace interface for PowerPC which is
2458 available since Linux kernel version 2.6.34. This automatically enables
2459 any hardware breakpoints and additional hardware watchpoints available in
2460 the processor. The old ptrace interface exposes just one hardware
2461 watchpoint and no hardware breakpoints.
2463 * GDB is now able to use the Data Value Compare (DVC) register available on
2464 embedded PowerPC processors to implement in hardware simple watchpoint
2465 conditions of the form:
2467 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2469 This works in native GDB running on Linux kernels with the extended ptrace
2470 interface mentioned above.
2472 *** Changes in GDB 7.1
2476 ** Namespace Support
2478 GDB now supports importing of namespaces in C++. This enables the
2479 user to inspect variables from imported namespaces. Support for
2480 namepace aliasing has also been added. So, if a namespace is
2481 aliased in the current scope (e.g. namepace C=A; ) the user can
2482 print variables using the alias (e.g. (gdb) print C::x).
2486 All known bugs relating to the printing of virtual base class were
2487 fixed. It is now possible to call overloaded static methods using a
2492 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2493 and reinterpret_cast<> are now handled by the C++ expression parser.
2497 Xilinx MicroBlaze microblaze-*-*
2502 Xilinx MicroBlaze microblaze
2505 * Multi-program debugging.
2507 GDB now has support for multi-program (a.k.a. multi-executable or
2508 multi-exec) debugging. This allows for debugging multiple inferiors
2509 simultaneously each running a different program under the same GDB
2510 session. See "Debugging Multiple Inferiors and Programs" in the
2511 manual for more information. This implied some user visible changes
2512 in the multi-inferior support. For example, "info inferiors" now
2513 lists inferiors that are not running yet or that have exited
2514 already. See also "New commands" and "New options" below.
2516 * New tracing features
2518 GDB's tracepoint facility now includes several new features:
2520 ** Trace state variables
2522 GDB tracepoints now include support for trace state variables, which
2523 are variables managed by the target agent during a tracing
2524 experiment. They are useful for tracepoints that trigger each
2525 other, so for instance one tracepoint can count hits in a variable,
2526 and then a second tracepoint has a condition that is true when the
2527 count reaches a particular value. Trace state variables share the
2528 $-syntax of GDB convenience variables, and can appear in both
2529 tracepoint actions and condition expressions. Use the "tvariable"
2530 command to create, and "info tvariables" to view; see "Trace State
2531 Variables" in the manual for more detail.
2535 GDB now includes an option for defining fast tracepoints, which
2536 targets may implement more efficiently, such as by installing a jump
2537 into the target agent rather than a trap instruction. The resulting
2538 speedup can be by two orders of magnitude or more, although the
2539 tradeoff is that some program locations on some target architectures
2540 might not allow fast tracepoint installation, for instance if the
2541 instruction to be replaced is shorter than the jump. To request a
2542 fast tracepoint, use the "ftrace" command, with syntax identical to
2543 the regular trace command.
2545 ** Disconnected tracing
2547 It is now possible to detach GDB from the target while it is running
2548 a trace experiment, then reconnect later to see how the experiment
2549 is going. In addition, a new variable disconnected-tracing lets you
2550 tell the target agent whether to continue running a trace if the
2551 connection is lost unexpectedly.
2555 GDB now has the ability to save the trace buffer into a file, and
2556 then use that file as a target, similarly to you can do with
2557 corefiles. You can select trace frames, print data that was
2558 collected in them, and use tstatus to display the state of the
2559 tracing run at the moment that it was saved. To create a trace
2560 file, use "tsave <filename>", and to use it, do "target tfile
2563 ** Circular trace buffer
2565 You can ask the target agent to handle the trace buffer as a
2566 circular buffer, discarding the oldest trace frames to make room for
2567 newer ones, by setting circular-trace-buffer to on. This feature may
2568 not be available for all target agents.
2573 The disassemble command, when invoked with two arguments, now requires
2574 the arguments to be comma-separated.
2577 The info variables command now displays variable definitions. Files
2578 which only declare a variable are not shown.
2581 The source command is now capable of sourcing Python scripts.
2582 This feature is dependent on the debugger being build with Python
2585 Related to this enhancement is also the introduction of a new command
2586 "set script-extension" (see below).
2588 * New commands (for set/show, see "New options" below)
2590 record save [<FILENAME>]
2591 Save a file (in core file format) containing the process record
2592 execution log for replay debugging at a later time.
2594 record restore <FILENAME>
2595 Restore the process record execution log that was saved at an
2596 earlier time, for replay debugging.
2598 add-inferior [-copies <N>] [-exec <FILENAME>]
2601 clone-inferior [-copies <N>] [ID]
2602 Make a new inferior ready to execute the same program another
2603 inferior has loaded.
2608 maint info program-spaces
2609 List the program spaces loaded into GDB.
2611 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2612 show remote interrupt-sequence
2613 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2614 as the sequence to the remote target in order to interrupt the execution.
2615 Ctrl-C is a default. Some system prefers BREAK which is high level of
2616 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2617 Magic SysRq g. It is BREAK signal and character 'g'.
2619 set remote interrupt-on-connect [on | off]
2620 show remote interrupt-on-connect
2621 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2622 remote target when gdb connects to it. This is needed when you debug
2625 set remotebreak [on | off]
2627 Deprecated. Use "set/show remote interrupt-sequence" instead.
2629 tvariable $NAME [ = EXP ]
2630 Create or modify a trace state variable.
2633 List trace state variables and their values.
2635 delete tvariable $NAME ...
2636 Delete one or more trace state variables.
2639 Evaluate the given expressions without collecting anything into the
2640 trace buffer. (Valid in tracepoint actions only.)
2642 ftrace FN / FILE:LINE / *ADDR
2643 Define a fast tracepoint at the given function, line, or address.
2645 * New expression syntax
2647 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2648 GDB now parses 0b101010 identically with 42.
2652 set follow-exec-mode new|same
2653 show follow-exec-mode
2654 Control whether GDB reuses the same inferior across an exec call or
2655 creates a new one. This is useful to be able to restart the old
2656 executable after the inferior having done an exec call.
2658 set default-collect EXPR, ...
2659 show default-collect
2660 Define a list of expressions to be collected at each tracepoint.
2661 This is a useful way to ensure essential items are not overlooked,
2662 such as registers or a critical global variable.
2664 set disconnected-tracing
2665 show disconnected-tracing
2666 If set to 1, the target is instructed to continue tracing if it
2667 loses its connection to GDB. If 0, the target is to stop tracing
2670 set circular-trace-buffer
2671 show circular-trace-buffer
2672 If set to on, the target is instructed to use a circular trace buffer
2673 and discard the oldest trace frames instead of stopping the trace due
2674 to a full trace buffer. If set to off, the trace stops when the buffer
2675 fills up. Some targets may not support this.
2677 set script-extension off|soft|strict
2678 show script-extension
2679 If set to "off", the debugger does not perform any script language
2680 recognition, and all sourced files are assumed to be GDB scripts.
2681 If set to "soft" (the default), files are sourced according to
2682 filename extension, falling back to GDB scripts if the first
2684 If set to "strict", files are sourced according to filename extension.
2686 set ada trust-PAD-over-XVS on|off
2687 show ada trust-PAD-over-XVS
2688 If off, activate a workaround against a bug in the debugging information
2689 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2690 the GCC sources for more information about the GNAT encoding and
2691 PAD types in particular). It is always safe to set this option to
2692 off, but this introduces a slight performance penalty. The default
2695 * Python API Improvements
2697 ** GDB provides the new class gdb.LazyString. This is useful in
2698 some pretty-printing cases. The new method gdb.Value.lazy_string
2699 provides a simple way to create objects of this type.
2701 ** The fields returned by gdb.Type.fields now have an
2702 `is_base_class' attribute.
2704 ** The new method gdb.Type.range returns the range of an array type.
2706 ** The new method gdb.parse_and_eval can be used to parse and
2707 evaluate an expression.
2709 * New remote packets
2712 Define a trace state variable.
2715 Get the current value of a trace state variable.
2718 Set desired tracing behavior upon disconnection.
2721 Set the trace buffer to be linear or circular.
2724 Get data about the tracepoints currently in use.
2728 Process record now works correctly with hardware watchpoints.
2730 Multiple bug fixes have been made to the mips-irix port, making it
2731 much more reliable. In particular:
2732 - Debugging threaded applications is now possible again. Previously,
2733 GDB would hang while starting the program, or while waiting for
2734 the program to stop at a breakpoint.
2735 - Attaching to a running process no longer hangs.
2736 - An error occurring while loading a core file has been fixed.
2737 - Changing the value of the PC register now works again. This fixes
2738 problems observed when using the "jump" command, or when calling
2739 a function from GDB, or even when assigning a new value to $pc.
2740 - With the "finish" and "return" commands, the return value for functions
2741 returning a small array is now correctly printed.
2742 - It is now possible to break on shared library code which gets executed
2743 during a shared library init phase (code executed while executing
2744 their .init section). Previously, the breakpoint would have no effect.
2745 - GDB is now able to backtrace through the signal handler for
2746 non-threaded programs.
2748 PIE (Position Independent Executable) programs debugging is now supported.
2749 This includes debugging execution of PIC (Position Independent Code) shared
2750 libraries although for that, it should be possible to run such libraries as an
2753 *** Changes in GDB 7.0
2755 * GDB now has an interface for JIT compilation. Applications that
2756 dynamically generate code can create symbol files in memory and register
2757 them with GDB. For users, the feature should work transparently, and
2758 for JIT developers, the interface is documented in the GDB manual in the
2759 "JIT Compilation Interface" chapter.
2761 * Tracepoints may now be conditional. The syntax is as for
2762 breakpoints; either an "if" clause appended to the "trace" command,
2763 or the "condition" command is available. GDB sends the condition to
2764 the target for evaluation using the same bytecode format as is used
2765 for tracepoint actions.
2767 * The disassemble command now supports: an optional /r modifier, print the
2768 raw instructions in hex as well as in symbolic form, and an optional /m
2769 modifier to print mixed source+assembly.
2771 * Process record and replay
2773 In a architecture environment that supports ``process record and
2774 replay'', ``process record and replay'' target can record a log of
2775 the process execution, and replay it with both forward and reverse
2778 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2779 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2780 set execution-direction {forward|reverse}, for targets that support
2783 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2784 feature is available with a native GDB running on kernel version
2787 * GDB now has support for multi-byte and wide character sets on the
2788 target. Strings whose character type is wchar_t, char16_t, or
2789 char32_t are now correctly printed. GDB supports wide- and unicode-
2790 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2791 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2792 `printf'. This feature requires iconv to work properly; if your
2793 system does not have a working iconv, GDB can use GNU libiconv. See
2794 the installation instructions for more information.
2796 * GDB now supports automatic retrieval of shared library files from
2797 remote targets. To use this feature, specify a system root that begins
2798 with the `remote:' prefix, either via the `set sysroot' command or via
2799 the `--with-sysroot' configure-time option.
2801 * "info sharedlibrary" now takes an optional regex of libraries to show,
2802 and it now reports if a shared library has no debugging information.
2804 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2805 now complete on file names.
2807 * When completing in expressions, gdb will attempt to limit
2808 completions to allowable structure or union fields, where appropriate.
2809 For instance, consider:
2811 # struct example { int f1; double f2; };
2812 # struct example variable;
2815 If the user types TAB at the end of this command line, the available
2816 completions will be "f1" and "f2".
2818 * Inlined functions are now supported. They show up in backtraces, and
2819 the "step", "next", and "finish" commands handle them automatically.
2821 * GDB now supports the token-splicing (##) and stringification (#)
2822 operators when expanding macros. It also supports variable-arity
2825 * GDB now supports inspecting extra signal information, exported by
2826 the new $_siginfo convenience variable. The feature is currently
2827 implemented on linux ARM, i386 and amd64.
2829 * GDB can now display the VFP floating point registers and NEON vector
2830 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2831 can provide these registers (requires Linux 2.6.30 or later). Remote
2832 and simulator targets may also provide them.
2834 * New remote packets
2837 Search memory for a sequence of bytes.
2840 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2841 operation over reliable transport links. Use of this packet is
2842 controlled by the `set remote noack-packet' command.
2845 Kill the process with the specified process ID. Use this in preference
2846 to `k' when multiprocess protocol extensions are supported.
2849 Obtains additional operating system information
2853 Read or write additional signal information.
2855 * Removed remote protocol undocumented extension
2857 An undocumented extension to the remote protocol's `S' stop reply
2858 packet that permited the stub to pass a process id was removed.
2859 Remote servers should use the `T' stop reply packet instead.
2861 * GDB now supports multiple function calling conventions according to the
2862 DWARF-2 DW_AT_calling_convention function attribute.
2864 * The SH target utilizes the aforementioned change to distinguish between gcc
2865 and Renesas calling convention. It also adds the new CLI commands
2866 `set/show sh calling-convention'.
2868 * GDB can now read compressed debug sections, as produced by GNU gold
2869 with the --compress-debug-sections=zlib flag.
2871 * 64-bit core files are now supported on AIX.
2873 * Thread switching is now supported on Tru64.
2875 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2876 which will be allocated using malloc later in program execution.
2878 * The qXfer:libraries:read remote procotol packet now allows passing a
2879 list of section offsets.
2881 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2882 conditions handling signals delivered during attach or thread creation
2883 have also been fixed.
2885 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2886 From the user's standpoint, all unqualified instances of True and False
2887 are treated as the standard definitions, regardless of context.
2889 * GDB now parses C++ symbol and type names more flexibly. For
2892 template<typename T> class C { };
2895 GDB will now correctly handle all of:
2897 ptype C<char const *>
2898 ptype C<char const*>
2899 ptype C<const char *>
2900 ptype C<const char*>
2902 * New features in the GDB remote stub, gdbserver
2904 - The "--wrapper" command-line argument tells gdbserver to use a
2905 wrapper program to launch programs for debugging.
2907 - On PowerPC and S/390 targets, it is now possible to use a single
2908 gdbserver executable to debug both 32-bit and 64-bit programs.
2909 (This requires gdbserver itself to be built as a 64-bit executable.)
2911 - gdbserver uses the new noack protocol mode for TCP connections to
2912 reduce communications latency, if also supported and enabled in GDB.
2914 - Support for the sparc64-linux-gnu target is now included in
2917 - The amd64-linux build of gdbserver now supports debugging both
2918 32-bit and 64-bit programs.
2920 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2921 now support hardware watchpoints, and will use them automatically
2926 GDB now has support for scripting using Python. Whether this is
2927 available is determined at configure time.
2929 New GDB commands can now be written in Python.
2931 * Ada tasking support
2933 Ada tasks can now be inspected in GDB. The following commands have
2937 Print the list of Ada tasks.
2939 Print detailed information about task number N.
2941 Print the task number of the current task.
2943 Switch the context of debugging to task number N.
2945 * Support for user-defined prefixed commands. The "define" command can
2946 add new commands to existing prefixes, e.g. "target".
2948 * Multi-inferior, multi-process debugging.
2950 GDB now has generalized support for multi-inferior debugging. See
2951 "Debugging Multiple Inferiors" in the manual for more information.
2952 Although availability still depends on target support, the command
2953 set is more uniform now. The GNU/Linux specific multi-forks support
2954 has been migrated to this new framework. This implied some user
2955 visible changes; see "New commands" and also "Removed commands"
2958 * Target descriptions can now describe the target OS ABI. See the
2959 "Target Description Format" section in the user manual for more
2962 * Target descriptions can now describe "compatible" architectures
2963 to indicate that the target can execute applications for a different
2964 architecture in addition to those for the main target architecture.
2965 See the "Target Description Format" section in the user manual for
2968 * Multi-architecture debugging.
2970 GDB now includes general supports for debugging applications on
2971 hybrid systems that use more than one single processor architecture
2972 at the same time. Each such hybrid architecture still requires
2973 specific support to be added. The only hybrid architecture supported
2974 in this version of GDB is the Cell Broadband Engine.
2976 * GDB now supports integrated debugging of Cell/B.E. applications that
2977 use both the PPU and SPU architectures. To enable support for hybrid
2978 Cell/B.E. debugging, you need to configure GDB to support both the
2979 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2980 --enable-targets configure option.
2982 * Non-stop mode debugging.
2984 For some targets, GDB now supports an optional mode of operation in
2985 which you can examine stopped threads while other threads continue
2986 to execute freely. This is referred to as non-stop mode, with the
2987 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2988 section in the user manual for more information.
2990 To be able to support remote non-stop debugging, a remote stub needs
2991 to implement the non-stop mode remote protocol extensions, as
2992 described in the "Remote Non-Stop" section of the user manual. The
2993 GDB remote stub, gdbserver, has been adjusted to support these
2994 extensions on linux targets.
2996 * New commands (for set/show, see "New options" below)
2998 catch syscall [NAME(S) | NUMBER(S)]
2999 Catch system calls. Arguments, which should be names of system
3000 calls or their numbers, mean catch only those syscalls. Without
3001 arguments, every syscall will be caught. When the inferior issues
3002 any of the specified syscalls, GDB will stop and announce the system
3003 call, both when it is called and when its call returns. This
3004 feature is currently available with a native GDB running on the
3005 Linux Kernel, under the following architectures: x86, x86_64,
3006 PowerPC and PowerPC64.
3008 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3010 Search memory for a sequence of bytes.
3012 maint set python print-stack
3013 maint show python print-stack
3014 Show a stack trace when an error is encountered in a Python script.
3017 Invoke CODE by passing it to the Python interpreter.
3022 These allow macros to be defined, undefined, and listed
3026 Show operating system information about processes.
3029 List the inferiors currently under GDB's control.
3032 Switch focus to inferior number NUM.
3035 Detach from inferior number NUM.
3038 Kill inferior number NUM.
3042 set spu stop-on-load
3043 show spu stop-on-load
3044 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3046 set spu auto-flush-cache
3047 show spu auto-flush-cache
3048 Control whether to automatically flush the software-managed cache
3049 during Cell/B.E. debugging.
3051 set sh calling-convention
3052 show sh calling-convention
3053 Control the calling convention used when calling SH target functions.
3056 show debug timestamp
3057 Control display of timestamps with GDB debugging output.
3059 set disassemble-next-line
3060 show disassemble-next-line
3061 Control display of disassembled source lines or instructions when
3064 set remote noack-packet
3065 show remote noack-packet
3066 Set/show the use of remote protocol QStartNoAckMode packet. See above
3067 under "New remote packets."
3069 set remote query-attached-packet
3070 show remote query-attached-packet
3071 Control use of remote protocol `qAttached' (query-attached) packet.
3073 set remote read-siginfo-object
3074 show remote read-siginfo-object
3075 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3078 set remote write-siginfo-object
3079 show remote write-siginfo-object
3080 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3083 set remote reverse-continue
3084 show remote reverse-continue
3085 Control use of remote protocol 'bc' (reverse-continue) packet.
3087 set remote reverse-step
3088 show remote reverse-step
3089 Control use of remote protocol 'bs' (reverse-step) packet.
3091 set displaced-stepping
3092 show displaced-stepping
3093 Control displaced stepping mode. Displaced stepping is a way to
3094 single-step over breakpoints without removing them from the debuggee.
3095 Also known as "out-of-line single-stepping".
3098 show debug displaced
3099 Control display of debugging info for displaced stepping.
3101 maint set internal-error
3102 maint show internal-error
3103 Control what GDB does when an internal error is detected.
3105 maint set internal-warning
3106 maint show internal-warning
3107 Control what GDB does when an internal warning is detected.
3112 Use a wrapper program to launch programs for debugging.
3114 set multiple-symbols (all|ask|cancel)
3115 show multiple-symbols
3116 The value of this variable can be changed to adjust the debugger behavior
3117 when an expression or a breakpoint location contains an ambiguous symbol
3118 name (an overloaded function name, for instance).
3120 set breakpoint always-inserted
3121 show breakpoint always-inserted
3122 Keep breakpoints always inserted in the target, as opposed to inserting
3123 them when resuming the target, and removing them when the target stops.
3124 This option can improve debugger performance on slow remote targets.
3126 set arm fallback-mode (arm|thumb|auto)
3127 show arm fallback-mode
3128 set arm force-mode (arm|thumb|auto)
3130 These commands control how ARM GDB determines whether instructions
3131 are ARM or Thumb. The default for both settings is auto, which uses
3132 the current CPSR value for instructions without symbols; previous
3133 versions of GDB behaved as if "set arm fallback-mode arm".
3135 set disable-randomization
3136 show disable-randomization
3137 Standalone programs run with the virtual address space randomization enabled
3138 by default on some platforms. This option keeps the addresses stable across
3139 multiple debugging sessions.
3143 Control whether other threads are stopped or not when some thread hits
3148 Requests that asynchronous execution is enabled in the target, if available.
3149 In this case, it's possible to resume target in the background, and interact
3150 with GDB while the target is running. "show target-async" displays the
3151 current state of asynchronous execution of the target.
3153 set target-wide-charset
3154 show target-wide-charset
3155 The target-wide-charset is the name of the character set that GDB
3156 uses when printing characters whose type is wchar_t.
3158 set tcp auto-retry (on|off)
3160 set tcp connect-timeout
3161 show tcp connect-timeout
3162 These commands allow GDB to retry failed TCP connections to a remote stub
3163 with a specified timeout period; this is useful if the stub is launched
3164 in parallel with GDB but may not be ready to accept connections immediately.
3166 set libthread-db-search-path
3167 show libthread-db-search-path
3168 Control list of directories which GDB will search for appropriate
3171 set schedule-multiple (on|off)
3172 show schedule-multiple
3173 Allow GDB to resume all threads of all processes or only threads of
3174 the current process.
3178 Use more aggressive caching for accesses to the stack. This improves
3179 performance of remote debugging (particularly backtraces) without
3180 affecting correctness.
3182 set interactive-mode (on|off|auto)
3183 show interactive-mode
3184 Control whether GDB runs in interactive mode (on) or not (off).
3185 When in interactive mode, GDB waits for the user to answer all
3186 queries. Otherwise, GDB does not wait and assumes the default
3187 answer. When set to auto (the default), GDB determines which
3188 mode to use based on the stdin settings.
3193 For program forks, this is replaced by the new more generic `info
3194 inferiors' command. To list checkpoints, you can still use the
3195 `info checkpoints' command, which was an alias for the `info forks'
3199 Replaced by the new `inferior' command. To switch between
3200 checkpoints, you can still use the `restart' command, which was an
3201 alias for the `fork' command.
3204 This is removed, since some targets don't have a notion of
3205 processes. To switch between processes, you can still use the
3206 `inferior' command using GDB's own inferior number.
3209 For program forks, this is replaced by the new more generic `kill
3210 inferior' command. To delete a checkpoint, you can still use the
3211 `delete checkpoint' command, which was an alias for the `delete
3215 For program forks, this is replaced by the new more generic `detach
3216 inferior' command. To detach a checkpoint, you can still use the
3217 `detach checkpoint' command, which was an alias for the `detach
3220 * New native configurations
3222 x86/x86_64 Darwin i[34567]86-*-darwin*
3224 x86_64 MinGW x86_64-*-mingw*
3228 Lattice Mico32 lm32-*
3229 x86 DICOS i[34567]86-*-dicos*
3230 x86_64 DICOS x86_64-*-dicos*
3233 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3234 (mingw32ce) debugging.
3240 These commands were actually not implemented on any target.
3242 *** Changes in GDB 6.8
3244 * New native configurations
3246 NetBSD/hppa hppa*-*netbsd*
3247 Xtensa GNU/Linux xtensa*-*-linux*
3251 NetBSD/hppa hppa*-*-netbsd*
3252 Xtensa GNU/Lunux xtensa*-*-linux*
3254 * Change in command line behavior -- corefiles vs. process ids.
3256 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3257 attaching to process NUMBER fails, GDB no longer attempts to open a
3258 core file named NUMBER. Attaching to a program using the -c option
3259 is no longer supported. Instead, use the '-p' or '--pid' options.
3261 * GDB can now be built as a native debugger for debugging Windows x86
3262 (mingw32) Portable Executable (PE) programs.
3264 * Pending breakpoints no longer change their number when their address
3267 * GDB now supports breakpoints with multiple locations,
3268 including breakpoints on C++ constructors, inside C++ templates,
3269 and in inlined functions.
3271 * GDB's ability to debug optimized code has been improved. GDB more
3272 accurately identifies function bodies and lexical blocks that occupy
3273 more than one contiguous range of addresses.
3275 * Target descriptions can now describe registers for PowerPC.
3277 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3278 registers on PowerPC targets.
3280 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3281 targets even when the libthread_db library is not available.
3283 * The GDB remote stub, gdbserver, now supports the new file transfer
3284 commands (remote put, remote get, and remote delete).
3286 * The GDB remote stub, gdbserver, now supports run and attach in
3287 extended-remote mode.
3289 * hppa*64*-*-hpux11* target broken
3290 The debugger is unable to start a program and fails with the following
3291 error: "Error trying to get information about dynamic linker".
3292 The gdb-6.7 release is also affected.
3294 * GDB now supports the --enable-targets= configure option to allow
3295 building a single GDB executable that supports multiple remote
3296 target architectures.
3298 * GDB now supports debugging C and C++ programs which use the
3299 Decimal Floating Point extension. In addition, the PowerPC target
3300 now has a set of pseudo-registers to inspect decimal float values
3301 stored in two consecutive float registers.
3303 * The -break-insert MI command can optionally create pending
3306 * Improved support for debugging Ada
3307 Many improvements to the Ada language support have been made. These
3309 - Better support for Ada2005 interface types
3310 - Improved handling of arrays and slices in general
3311 - Better support for Taft-amendment types
3312 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3314 - Improved command completion in Ada
3317 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3322 set print frame-arguments (all|scalars|none)
3323 show print frame-arguments
3324 The value of this variable can be changed to control which argument
3325 values should be printed by the debugger when displaying a frame.
3330 Transfer files to and from a remote target, and delete remote files.
3337 Transfer files to and from a remote target, and delete remote files.
3339 * New remote packets
3346 Open, close, read, write, and delete files on the remote system.
3349 Attach to an existing process on the remote system, in extended-remote
3353 Run a new process on the remote system, in extended-remote mode.
3355 *** Changes in GDB 6.7
3357 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3358 bfd, libiberty and opcodes, as revealed by static analysis donated by
3359 Coverity, Inc. (http://scan.coverity.com).
3361 * When looking up multiply-defined global symbols, GDB will now prefer the
3362 symbol definition in the current shared library if it was built using the
3363 -Bsymbolic linker option.
3365 * When the Text User Interface (TUI) is not configured, GDB will now
3366 recognize the -tui command-line option and print a message that the TUI
3369 * The GDB remote stub, gdbserver, now has lower overhead for high
3370 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3372 * GDB for MIPS targets now autodetects whether a remote target provides
3373 32-bit or 64-bit register values.
3375 * Support for C++ member pointers has been improved.
3377 * GDB now understands XML target descriptions, which specify the
3378 target's overall architecture. GDB can read a description from
3379 a local file or over the remote serial protocol.
3381 * Vectors of single-byte data use a new integer type which is not
3382 automatically displayed as character or string data.
3384 * The /s format now works with the print command. It displays
3385 arrays of single-byte integers and pointers to single-byte integers
3388 * Target descriptions can now describe target-specific registers,
3389 for architectures which have implemented the support (currently
3390 only ARM, M68K, and MIPS).
3392 * GDB and the GDB remote stub, gdbserver, now support the XScale
3395 * The GDB remote stub, gdbserver, has been updated to support
3396 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3397 has been rewritten to use the standard GDB remote protocol.
3399 * GDB can now step into C++ functions which are called through thunks.
3401 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3403 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3404 layout. It also supports a TextSeg= and DataSeg= response when only
3405 segment base addresses (rather than offsets) are available.
3407 * The /i format now outputs any trailing branch delay slot instructions
3408 immediately following the last instruction within the count specified.
3410 * The GDB remote protocol "T" stop reply packet now supports a
3411 "library" response. Combined with the new "qXfer:libraries:read"
3412 packet, this response allows GDB to debug shared libraries on targets
3413 where the operating system manages the list of loaded libraries (e.g.
3414 Windows and SymbianOS).
3416 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3417 (DLLs) on Windows and Windows CE targets.
3419 * GDB now supports a faster verification that a .debug file matches its binary
3420 according to its build-id signature, if the signature is present.
3426 Enable or disable hardware flow control (RTS/CTS) on the serial port
3427 when debugging using remote targets.
3429 set mem inaccessible-by-default
3430 show mem inaccessible-by-default
3431 If the target supplies a memory map, for instance via the remote
3432 protocol's "qXfer:memory-map:read" packet, setting this variable
3433 prevents GDB from accessing memory outside the memory map. This
3434 is useful for targets with memory mapped registers or which react
3435 badly to accesses of unmapped address space.
3437 set breakpoint auto-hw
3438 show breakpoint auto-hw
3439 If the target supplies a memory map, for instance via the remote
3440 protocol's "qXfer:memory-map:read" packet, setting this variable
3441 lets GDB use hardware breakpoints automatically for memory regions
3442 where it can not use software breakpoints. This covers both the
3443 "break" command and internal breakpoints used for other commands
3444 including "next" and "finish".
3447 catch exception unhandled
3448 Stop the program execution when Ada exceptions are raised.
3451 Stop the program execution when an Ada assertion failed.
3455 Set an alternate system root for target files. This is a more
3456 general version of "set solib-absolute-prefix", which is now
3457 an alias to "set sysroot".
3460 Provide extended SPU facility status information. This set of
3461 commands is available only when debugging the Cell/B.E. SPU
3464 * New native configurations
3466 OpenBSD/sh sh*-*openbsd*
3469 unset tdesc filename
3471 Use the specified local file as an XML target description, and do
3472 not query the target for its built-in description.
3476 OpenBSD/sh sh*-*-openbsd*
3477 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3478 Toshiba Media Processor mep-elf
3480 * New remote packets
3483 Ignore the specified signals; pass them directly to the debugged program
3484 without stopping other threads or reporting them to GDB.
3486 qXfer:features:read:
3487 Read an XML target description from the target, which describes its
3492 Read or write contents of an spufs file on the target system. These
3493 packets are available only on the Cell/B.E. SPU architecture.
3495 qXfer:libraries:read:
3496 Report the loaded shared libraries. Combined with new "T" packet
3497 response, this packet allows GDB to debug shared libraries on
3498 targets where the operating system manages the list of loaded
3499 libraries (e.g. Windows and SymbianOS).
3503 Support for these obsolete configurations has been removed.
3511 i[34567]86-*-lynxos*
3512 i[34567]86-*-netware*
3513 i[34567]86-*-sco3.2v5*
3514 i[34567]86-*-sco3.2v4*
3516 i[34567]86-*-sysv4.2*
3519 i[34567]86-*-unixware2*
3520 i[34567]86-*-unixware*
3529 * Other removed features
3536 Various m68k-only ROM monitors.
3543 Various Renesas ROM monitors and debugging interfaces for SH and
3548 Support for a Macraigor serial interface to on-chip debugging.
3549 GDB does not directly support the newer parallel or USB
3554 A debug information format. The predecessor to DWARF 2 and
3555 DWARF 3, which are still supported.
3557 Support for the HP aCC compiler on HP-UX/PA-RISC
3559 SOM-encapsulated symbolic debugging information, automatic
3560 invocation of pxdb, and the aCC custom C++ ABI. This does not
3561 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3562 with aCC can still be debugged on an assembly level.
3564 MIPS ".pdr" sections
3566 A MIPS-specific format used to describe stack frame layout
3567 in debugging information.
3571 GDB could work with an older version of Guile to debug
3572 the interpreter and Scheme programs running in it.
3574 set mips stack-arg-size
3575 set mips saved-gpreg-size
3577 Use "set mips abi" to control parameter passing for MIPS.
3579 *** Changes in GDB 6.6
3584 Cell Broadband Engine SPU spu-elf
3586 * GDB can now be configured as a cross-debugger targeting native Windows
3587 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3588 running on a Windows system over TCP/IP to debug Windows programs.
3590 * The GDB remote stub, gdbserver, has been updated to support Windows and
3591 Cygwin debugging. Both single-threaded and multi-threaded programs are
3594 * The "set trust-readonly-sections" command works again. This command was
3595 broken in GDB 6.3, 6.4, and 6.5.
3597 * The "load" command now supports writing to flash memory, if the remote
3598 stub provides the required support.
3600 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3601 longer requires symbolic debug information (e.g. DWARF-2).
3606 unset substitute-path
3607 show substitute-path
3608 Manage a list of substitution rules that GDB uses to rewrite the name
3609 of the directories where the sources are located. This can be useful
3610 for instance when the sources were moved to a different location
3611 between compilation and debugging.
3615 Print each CLI command as it is executed. Each command is prefixed with
3616 a number of `+' symbols representing the nesting depth.
3617 The source command now has a `-v' option to enable the same feature.
3621 The ARM Demon monitor support (RDP protocol, "target rdp").
3623 Kernel Object Display, an embedded debugging feature which only worked with
3624 an obsolete version of Cisco IOS.
3626 The 'set download-write-size' and 'show download-write-size' commands.
3628 * New remote packets
3631 Tell a stub about GDB client features, and request remote target features.
3632 The first feature implemented is PacketSize, which allows the target to
3633 specify the size of packets it can handle - to minimize the number of
3634 packets required and improve performance when connected to a remote
3638 Fetch an OS auxilliary vector from the remote stub. This packet is a
3639 more efficient replacement for qPart:auxv:read.
3641 qXfer:memory-map:read:
3642 Fetch a memory map from the remote stub, including information about
3643 RAM, ROM, and flash memory devices.
3648 Erase and program a flash memory device.
3650 * Removed remote packets
3653 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3654 used it, and only gdbserver implemented it.
3656 *** Changes in GDB 6.5
3660 Renesas M32C/M16C m32c-elf
3662 Morpho Technologies ms1 ms1-elf
3666 init-if-undefined Initialize a convenience variable, but
3667 only if it doesn't already have a value.
3669 The following commands are presently only implemented for native GNU/Linux:
3671 checkpoint Save a snapshot of the program state.
3673 restart <n> Return the program state to a
3674 previously saved state.
3676 info checkpoints List currently saved checkpoints.
3678 delete-checkpoint <n> Delete a previously saved checkpoint.
3680 set|show detach-on-fork Tell gdb whether to detach from a newly
3681 forked process, or to keep debugging it.
3683 info forks List forks of the user program that
3684 are available to be debugged.
3686 fork <n> Switch to debugging one of several
3687 forks of the user program that are
3688 available to be debugged.
3690 delete-fork <n> Delete a fork from the list of forks
3691 that are available to be debugged (and
3692 kill the forked process).
3694 detach-fork <n> Delete a fork from the list of forks
3695 that are available to be debugged (and
3696 allow the process to continue).
3700 Morpho Technologies ms2 ms1-elf
3702 * Improved Windows host support
3704 GDB now builds as a cross debugger hosted on i686-mingw32, including
3705 native console support, and remote communications using either
3706 network sockets or serial ports.
3708 * Improved Modula-2 language support
3710 GDB can now print most types in the Modula-2 syntax. This includes:
3711 basic types, set types, record types, enumerated types, range types,
3712 pointer types and ARRAY types. Procedure var parameters are correctly
3713 printed and hexadecimal addresses and character constants are also
3714 written in the Modula-2 syntax. Best results can be obtained by using
3715 GNU Modula-2 together with the -gdwarf-2 command line option.
3719 The ARM rdi-share module.
3721 The Netware NLM debug server.
3723 *** Changes in GDB 6.4
3725 * New native configurations
3727 OpenBSD/arm arm*-*-openbsd*
3728 OpenBSD/mips64 mips64-*-openbsd*
3732 Morpho Technologies ms1 ms1-elf
3734 * New command line options
3736 --batch-silent As for --batch, but totally silent.
3737 --return-child-result The debugger will exist with the same value
3738 the child (debugged) program exited with.
3739 --eval-command COMMAND, -ex COMMAND
3740 Execute a single GDB CLI command. This may be
3741 specified multiple times and in conjunction
3742 with the --command (-x) option.
3744 * Deprecated commands removed
3746 The following commands, that were deprecated in 2000, have been
3750 set|show arm disassembly-flavor set|show arm disassembler
3751 othernames set arm disassembler
3752 set|show remotedebug set|show debug remote
3753 set|show archdebug set|show debug arch
3754 set|show eventdebug set|show debug event
3757 * New BSD user-level threads support
3759 It is now possible to debug programs using the user-level threads
3760 library on OpenBSD and FreeBSD. Currently supported (target)
3763 FreeBSD/amd64 x86_64-*-freebsd*
3764 FreeBSD/i386 i386-*-freebsd*
3765 OpenBSD/i386 i386-*-openbsd*
3767 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3768 are not yet supported.
3770 * New support for Matsushita MN10300 w/sim added
3771 (Work in progress). mn10300-elf.
3773 * REMOVED configurations and files
3775 VxWorks and the XDR protocol *-*-vxworks
3776 Motorola MCORE mcore-*-*
3777 National Semiconductor NS32000 ns32k-*-*
3779 * New "set print array-indexes" command
3781 After turning this setting "on", GDB prints the index of each element
3782 when displaying arrays. The default is "off" to preserve the previous
3785 * VAX floating point support
3787 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3789 * User-defined command support
3791 In addition to using $arg0..$arg9 for argument passing, it is now possible
3792 to use $argc to determine now many arguments have been passed. See the
3793 section on user-defined commands in the user manual for more information.
3795 *** Changes in GDB 6.3:
3797 * New command line option
3799 GDB now accepts -l followed by a number to set the timeout for remote
3802 * GDB works with GCC -feliminate-dwarf2-dups
3804 GDB now supports a more compact representation of DWARF-2 debug
3805 information using DW_FORM_ref_addr references. These are produced
3806 by GCC with the option -feliminate-dwarf2-dups and also by some
3807 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3808 to use -feliminate-dwarf2-dups.
3810 * Internationalization
3812 When supported by the host system, GDB will be built with
3813 internationalization (libintl). The task of marking up the sources is
3814 continued, we're looking forward to our first translation.
3818 Initial support for debugging programs compiled with the GNAT
3819 implementation of the Ada programming language has been integrated
3820 into GDB. In this release, support is limited to expression evaluation.
3822 * New native configurations
3824 GNU/Linux/m32r m32r-*-linux-gnu
3828 GDB's remote protocol now includes support for the 'p' packet. This
3829 packet is used to fetch individual registers from a remote inferior.
3831 * END-OF-LIFE registers[] compatibility module
3833 GDB's internal register infrastructure has been completely rewritten.
3834 The new infrastructure making possible the implementation of key new
3835 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3838 GDB 6.3 will be the last release to include the the registers[]
3839 compatibility module that allowed out-of-date configurations to
3840 continue to work. This change directly impacts the following
3850 powerpc bdm protocol
3852 Unless there is activity to revive these configurations, they will be
3853 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3855 * OBSOLETE configurations and files
3857 Configurations that have been declared obsolete in this release have
3858 been commented out. Unless there is activity to revive these
3859 configurations, the next release of GDB will have their sources
3860 permanently REMOVED.
3869 *** Changes in GDB 6.2.1:
3871 * MIPS `break main; run' gave an heuristic-fence-post warning
3873 When attempting to run even a simple program, a warning about
3874 heuristic-fence-post being hit would be reported. This problem has
3877 * MIPS IRIX 'long double' crashed GDB
3879 When examining a long double variable, GDB would get a segmentation
3880 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3881 IRIX long double values).
3885 A bug in the VAX stack code was causing problems with the "next"
3886 command. This problem has been fixed.
3888 *** Changes in GDB 6.2:
3890 * Fix for ``many threads''
3892 On GNU/Linux systems that use the NPTL threads library, a program
3893 rapidly creating and deleting threads would confuse GDB leading to the
3896 ptrace: No such process.
3897 thread_db_get_info: cannot get thread info: generic error
3899 This problem has been fixed.
3901 * "-async" and "-noasync" options removed.
3903 Support for the broken "-noasync" option has been removed (it caused
3906 * New ``start'' command.
3908 This command runs the program until the begining of the main procedure.
3910 * New BSD Kernel Data Access Library (libkvm) interface
3912 Using ``target kvm'' it is now possible to debug kernel core dumps and
3913 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3914 platforms. Currently supported (native-only) configurations are:
3916 FreeBSD/amd64 x86_64-*-freebsd*
3917 FreeBSD/i386 i?86-*-freebsd*
3918 NetBSD/i386 i?86-*-netbsd*
3919 NetBSD/m68k m68*-*-netbsd*
3920 NetBSD/sparc sparc-*-netbsd*
3921 OpenBSD/amd64 x86_64-*-openbsd*
3922 OpenBSD/i386 i?86-*-openbsd*
3923 OpenBSD/m68k m68*-openbsd*
3924 OpenBSD/sparc sparc-*-openbsd*
3926 * Signal trampoline code overhauled
3928 Many generic problems with GDB's signal handling code have been fixed.
3929 These include: backtraces through non-contiguous stacks; recognition
3930 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3931 call; backtrace through a signal trampoline; step into and out of
3932 signal handlers; and single-stepping in the signal trampoline.
3934 Please note that kernel bugs are a limiting factor here. These
3935 features have been shown to work on an s390 GNU/Linux system that
3936 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3938 * Cygwin support for DWARF 2 added.
3940 * New native configurations
3942 GNU/Linux/hppa hppa*-*-linux*
3943 OpenBSD/hppa hppa*-*-openbsd*
3944 OpenBSD/m68k m68*-*-openbsd*
3945 OpenBSD/m88k m88*-*-openbsd*
3946 OpenBSD/powerpc powerpc-*-openbsd*
3947 NetBSD/vax vax-*-netbsd*
3948 OpenBSD/vax vax-*-openbsd*
3950 * END-OF-LIFE frame compatibility module
3952 GDB's internal frame infrastructure has been completely rewritten.
3953 The new infrastructure making it possible to support key new features
3954 including DWARF 2 Call Frame Information. To aid in the task of
3955 migrating old configurations to this new infrastructure, a
3956 compatibility module, that allowed old configurations to continue to
3957 work, was also included.
3959 GDB 6.2 will be the last release to include this frame compatibility
3960 module. This change directly impacts the following configurations:
3970 Unless there is activity to revive these configurations, they will be
3971 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3973 * REMOVED configurations and files
3975 Sun 3, running SunOS 3 m68*-*-sunos3*
3976 Sun 3, running SunOS 4 m68*-*-sunos4*
3977 Sun 2, running SunOS 3 m68000-*-sunos3*
3978 Sun 2, running SunOS 4 m68000-*-sunos4*
3979 Motorola 680x0 running LynxOS m68*-*-lynxos*
3980 AT&T 3b1/Unix pc m68*-att-*
3981 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3982 decstation mips-dec-* mips-little-*
3983 riscos mips-*-riscos* mips-*-sysv*
3984 sonymips mips-sony-*
3985 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3987 *** Changes in GDB 6.1.1:
3989 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3991 The TUI (Text-mode User Interface) is now built as part of a default
3992 GDB configuration. It is enabled by either selecting the TUI with the
3993 command line option "-i=tui" or by running the separate "gdbtui"
3994 program. For more information on the TUI, see the manual "Debugging
3997 * Pending breakpoint support (also included in GDB 6.1)
3999 Support has been added to allow you to specify breakpoints in shared
4000 libraries that have not yet been loaded. If a breakpoint location
4001 cannot be found, and the "breakpoint pending" option is set to auto,
4002 GDB queries you if you wish to make the breakpoint pending on a future
4003 shared-library load. If and when GDB resolves the breakpoint symbol,
4004 the pending breakpoint is removed as one or more regular breakpoints
4007 Pending breakpoints are very useful for GCJ Java debugging.
4009 * Fixed ISO-C build problems
4011 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4012 non ISO-C code that stopped them being built using a more strict ISO-C
4013 compiler (e.g., IBM's C compiler).
4015 * Fixed build problem on IRIX 5
4017 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4018 wasn't able to compile compile on an IRIX 5 system.
4020 * Added execute permission to gdb/gdbserver/configure
4022 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4023 permission. This bug would cause configure to fail on a number of
4024 systems (Solaris, IRIX). Ref: server/519.
4026 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4028 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4029 has been updated to use constant array sizes.
4031 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4033 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4034 its generated DWARF Call Frame Info. This encoding was causing GDB to
4035 panic, that panic has been fixed. Ref: gdb/1628.
4037 * Fixed a problem when examining parameters in shared library code.
4039 When examining parameters in optimized shared library code generated
4040 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4041 not available''. GDB now correctly displays the variable's value.
4043 *** Changes in GDB 6.1:
4045 * Removed --with-mmalloc
4047 Support for the mmalloc memory manager has been removed, as it
4048 conflicted with the internal gdb byte cache.
4050 * Changes in AMD64 configurations
4052 The AMD64 target now includes the %cs and %ss registers. As a result
4053 the AMD64 remote protocol has changed; this affects the floating-point
4054 and SSE registers. If you rely on those registers for your debugging,
4055 you should upgrade gdbserver on the remote side.
4057 * Revised SPARC target
4059 The SPARC target has been completely revised, incorporating the
4060 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4061 support for LynxOS and SunOS 4 has been dropped. Calling functions
4062 from within GDB on operating systems with a non-executable stack
4063 (Solaris, OpenBSD) now works.
4067 GDB has a new C++ demangler which does a better job on the mangled
4068 names generated by current versions of g++. It also runs faster, so
4069 with this and other changes gdb should now start faster on large C++
4072 * DWARF 2 Location Expressions
4074 GDB support for location expressions has been extended to support function
4075 arguments and frame bases. Older versions of GDB could crash when they
4078 * C++ nested types and namespaces
4080 GDB's support for nested types and namespaces in C++ has been
4081 improved, especially if you use the DWARF 2 debugging format. (This
4082 is the default for recent versions of GCC on most platforms.)
4083 Specifically, if you have a class "Inner" defined within a class or
4084 namespace "Outer", then GDB realizes that the class's name is
4085 "Outer::Inner", not simply "Inner". This should greatly reduce the
4086 frequency of complaints about not finding RTTI symbols. In addition,
4087 if you are stopped at inside of a function defined within a namespace,
4088 GDB modifies its name lookup accordingly.
4090 * New native configurations
4092 NetBSD/amd64 x86_64-*-netbsd*
4093 OpenBSD/amd64 x86_64-*-openbsd*
4094 OpenBSD/alpha alpha*-*-openbsd*
4095 OpenBSD/sparc sparc-*-openbsd*
4096 OpenBSD/sparc64 sparc64-*-openbsd*
4098 * New debugging protocols
4100 M32R with SDI protocol m32r-*-elf*
4102 * "set prompt-escape-char" command deleted.
4104 The command "set prompt-escape-char" has been deleted. This command,
4105 and its very obscure effet on GDB's prompt, was never documented,
4106 tested, nor mentioned in the NEWS file.
4108 * OBSOLETE configurations and files
4110 Configurations that have been declared obsolete in this release have
4111 been commented out. Unless there is activity to revive these
4112 configurations, the next release of GDB will have their sources
4113 permanently REMOVED.
4115 Sun 3, running SunOS 3 m68*-*-sunos3*
4116 Sun 3, running SunOS 4 m68*-*-sunos4*
4117 Sun 2, running SunOS 3 m68000-*-sunos3*
4118 Sun 2, running SunOS 4 m68000-*-sunos4*
4119 Motorola 680x0 running LynxOS m68*-*-lynxos*
4120 AT&T 3b1/Unix pc m68*-att-*
4121 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4122 decstation mips-dec-* mips-little-*
4123 riscos mips-*-riscos* mips-*-sysv*
4124 sonymips mips-sony-*
4125 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4127 * REMOVED configurations and files
4129 SGI Irix-4.x mips-sgi-irix4 or iris4
4130 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4131 Z8000 simulator z8k-zilog-none or z8ksim
4132 Matsushita MN10200 w/simulator mn10200-*-*
4133 H8/500 simulator h8500-hitachi-hms or h8500hms
4134 HP/PA running BSD hppa*-*-bsd*
4135 HP/PA running OSF/1 hppa*-*-osf*
4136 HP/PA Pro target hppa*-*-pro*
4137 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4138 386BSD i[3456]86-*-bsd*
4139 Sequent family i[3456]86-sequent-sysv4*
4140 i[3456]86-sequent-sysv*
4141 i[3456]86-sequent-bsd*
4142 SPARC running LynxOS sparc-*-lynxos*
4143 SPARC running SunOS 4 sparc-*-sunos4*
4144 Tsqware Sparclet sparclet-*-*
4145 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4147 *** Changes in GDB 6.0:
4151 Support for debugging the Objective-C programming language has been
4152 integrated into GDB.
4154 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4156 DWARF 2's Call Frame Information makes available compiler generated
4157 information that more exactly describes the program's run-time stack.
4158 By using this information, GDB is able to provide more robust stack
4161 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4162 have been updated to use a new backtrace mechanism which includes
4163 DWARF 2 CFI support.
4167 GDB's remote protocol has been extended to include support for hosted
4168 file I/O (where the remote target uses GDB's file system). See GDB's
4169 remote protocol documentation for details.
4171 * All targets using the new architecture framework.
4173 All of GDB's targets have been updated to use the new internal
4174 architecture framework. The way is now open for future GDB releases
4175 to include cross-architecture native debugging support (i386 on amd64,
4178 * GNU/Linux's Thread Local Storage (TLS)
4180 GDB now includes support for for the GNU/Linux implementation of
4181 per-thread variables.
4183 * GNU/Linux's Native POSIX Thread Library (NPTL)
4185 GDB's thread code has been updated to work with either the new
4186 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4188 * Separate debug info.
4190 GDB, in conjunction with BINUTILS, now supports a mechanism for
4191 automatically loading debug information from a separate file. Instead
4192 of shipping full debug and non-debug versions of system libraries,
4193 system integrators can now instead ship just the stripped libraries
4194 and optional debug files.
4196 * DWARF 2 Location Expressions
4198 DWARF 2 Location Expressions allow the compiler to more completely
4199 describe the location of variables (even in optimized code) to the
4202 GDB now includes preliminary support for location expressions (support
4203 for DW_OP_piece is still missing).
4207 A number of long standing bugs that caused GDB to die while starting a
4208 Java application have been fixed. GDB's Java support is now
4209 considered "useable".
4211 * GNU/Linux support for fork, vfork, and exec.
4213 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4214 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4217 * GDB supports logging output to a file
4219 There are two new commands, "set logging" and "show logging", which can be
4220 used to capture GDB's output to a file.
4222 * The meaning of "detach" has changed for gdbserver
4224 The "detach" command will now resume the application, as documented. To
4225 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4228 * d10v, m68hc11 `regs' command deprecated
4230 The `info registers' command has been updated so that it displays the
4231 registers using a format identical to the old `regs' command.
4235 A new command, "maint set profile on/off", has been added. This command can
4236 be used to enable or disable profiling while running GDB, to profile a
4237 session or a set of commands. In addition there is a new configure switch,
4238 "--enable-profiling", which will cause GDB to be compiled with profiling
4239 data, for more informative profiling results.
4241 * Default MI syntax changed to "mi2".
4243 The default MI (machine interface) syntax, enabled by the command line
4244 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4245 "mi1", can be enabled by specifying the option "-i=mi1".
4247 Support for the original "mi0" syntax (included in GDB 5.0) has been
4250 Fix for gdb/192: removed extraneous space when displaying frame level.
4251 Fix for gdb/672: update changelist is now output in mi list format.
4252 Fix for gdb/702: a -var-assign that updates the value now shows up
4253 in a subsequent -var-update.
4255 * New native configurations.
4257 FreeBSD/amd64 x86_64-*-freebsd*
4259 * Multi-arched targets.
4261 HP/PA HPUX11 hppa*-*-hpux*
4262 Renesas M32R/D w/simulator m32r-*-elf*
4264 * OBSOLETE configurations and files
4266 Configurations that have been declared obsolete in this release have
4267 been commented out. Unless there is activity to revive these
4268 configurations, the next release of GDB will have their sources
4269 permanently REMOVED.
4271 Z8000 simulator z8k-zilog-none or z8ksim
4272 Matsushita MN10200 w/simulator mn10200-*-*
4273 H8/500 simulator h8500-hitachi-hms or h8500hms
4274 HP/PA running BSD hppa*-*-bsd*
4275 HP/PA running OSF/1 hppa*-*-osf*
4276 HP/PA Pro target hppa*-*-pro*
4277 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4278 Sequent family i[3456]86-sequent-sysv4*
4279 i[3456]86-sequent-sysv*
4280 i[3456]86-sequent-bsd*
4281 Tsqware Sparclet sparclet-*-*
4282 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4284 * REMOVED configurations and files
4287 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4288 IBM AIX PS/2 i[3456]86-*-aix
4289 i386 running Mach 3.0 i[3456]86-*-mach3*
4290 i386 running Mach i[3456]86-*-mach*
4291 i386 running OSF/1 i[3456]86-*osf1mk*
4292 HP/Apollo 68k Family m68*-apollo*-sysv*,
4294 m68*-hp-bsd*, m68*-hp-hpux*
4295 Argonaut Risc Chip (ARC) arc-*-*
4296 Mitsubishi D30V d30v-*-*
4297 Fujitsu FR30 fr30-*-elf*
4298 OS/9000 i[34]86-*-os9k
4299 I960 with MON960 i960-*-coff
4301 * MIPS $fp behavior changed
4303 The convenience variable $fp, for the MIPS, now consistently returns
4304 the address of the current frame's base. Previously, depending on the
4305 context, $fp could refer to either $sp or the current frame's base
4306 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4307 The GNU Source-Level Debugger''.
4309 *** Changes in GDB 5.3:
4311 * GNU/Linux shared library multi-threaded performance improved.
4313 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4314 `/proc', in preference to `ptrace' for memory reads. This may result
4315 in an improvement in the start-up time of multi-threaded, shared
4316 library applications when run under GDB. One GDB user writes: ``loads
4317 shared libs like mad''.
4319 * ``gdbserver'' now supports multi-threaded applications on some targets
4321 Support for debugging multi-threaded applications which use
4322 the GNU/Linux LinuxThreads package has been added for
4323 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4324 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4326 * GDB now supports C/C++ preprocessor macros.
4328 GDB now expands preprocessor macro invocations in C/C++ expressions,
4329 and provides various commands for showing macro definitions and how
4332 The new command `macro expand EXPRESSION' expands any macro
4333 invocations in expression, and shows the result.
4335 The new command `show macro MACRO-NAME' shows the definition of the
4336 macro named MACRO-NAME, and where it was defined.
4338 Most compilers don't include information about macros in the debugging
4339 information by default. In GCC 3.1, for example, you need to compile
4340 your program with the options `-gdwarf-2 -g3'. If the macro
4341 information is present in the executable, GDB will read it.
4343 * Multi-arched targets.
4345 DEC Alpha (partial) alpha*-*-*
4346 DEC VAX (partial) vax-*-*
4348 National Semiconductor NS32000 (partial) ns32k-*-*
4349 Motorola 68000 (partial) m68k-*-*
4350 Motorola MCORE mcore-*-*
4354 Fujitsu FRV architecture added by Red Hat frv*-*-*
4357 * New native configurations
4359 Alpha NetBSD alpha*-*-netbsd*
4360 SH NetBSD sh*-*-netbsdelf*
4361 MIPS NetBSD mips*-*-netbsd*
4362 UltraSPARC NetBSD sparc64-*-netbsd*
4364 * OBSOLETE configurations and files
4366 Configurations that have been declared obsolete in this release have
4367 been commented out. Unless there is activity to revive these
4368 configurations, the next release of GDB will have their sources
4369 permanently REMOVED.
4371 Mitsubishi D30V d30v-*-*
4372 OS/9000 i[34]86-*-os9k
4373 IBM AIX PS/2 i[3456]86-*-aix
4374 Fujitsu FR30 fr30-*-elf*
4375 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4376 Argonaut Risc Chip (ARC) arc-*-*
4377 i386 running Mach 3.0 i[3456]86-*-mach3*
4378 i386 running Mach i[3456]86-*-mach*
4379 i386 running OSF/1 i[3456]86-*osf1mk*
4380 HP/Apollo 68k Family m68*-apollo*-sysv*,
4382 m68*-hp-bsd*, m68*-hp-hpux*
4383 I960 with MON960 i960-*-coff
4385 * OBSOLETE languages
4387 CHILL, a Pascal like language used by telecommunications companies.
4389 * REMOVED configurations and files
4391 AMD 29k family via UDI a29k-amd-udi, udi29k
4392 A29K VxWorks a29k-*-vxworks
4393 AMD 29000 embedded, using EBMON a29k-none-none
4394 AMD 29000 embedded with COFF a29k-none-coff
4395 AMD 29000 embedded with a.out a29k-none-aout
4397 testsuite/gdb.hp/gdb.threads-hp/ directory
4399 * New command "set max-user-call-depth <nnn>"
4401 This command allows the user to limit the call depth of user-defined
4402 commands. The default is 1024.
4404 * Changes in FreeBSD/i386 native debugging.
4406 Support for the "generate-core-file" has been added.
4408 * New commands "dump", "append", and "restore".
4410 These commands allow data to be copied from target memory
4411 to a bfd-format or binary file (dump and append), and back
4412 from a file into memory (restore).
4414 * Improved "next/step" support on multi-processor Alpha Tru64.
4416 The previous single-step mechanism could cause unpredictable problems,
4417 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4418 of a software single-step mechanism prevents this.
4420 *** Changes in GDB 5.2.1:
4428 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4429 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4430 Fix, by Joel Brobecker imported from mainline.
4432 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4433 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4434 Fix, by Fred Fish, imported from mainline.
4436 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4437 Surprisingly enough, it works now.
4438 By Michal Ludvig, imported from mainline.
4440 i386 hardware watchpoint support:
4441 avoid misses on second run for some targets.
4442 By Pierre Muller, imported from mainline.
4444 *** Changes in GDB 5.2:
4446 * New command "set trust-readonly-sections on[off]".
4448 This command is a hint that tells gdb that read-only sections
4449 really are read-only (ie. that their contents will not change).
4450 In this mode, gdb will go to the object file rather than the
4451 target to read memory from read-only sections (such as ".text").
4452 This can be a significant performance improvement on some
4453 (notably embedded) targets.
4455 * New command "generate-core-file" (or "gcore").
4457 This new gdb command allows the user to drop a core file of the child
4458 process state at any time. So far it's been implemented only for
4459 GNU/Linux and Solaris, but should be relatively easily ported to other
4460 hosts. Argument is core file name (defaults to core.<pid>).
4462 * New command line option
4464 GDB now accepts --pid or -p followed by a process id.
4466 * Change in command line behavior -- corefiles vs. process ids.
4468 There is a subtle behavior in the way in which GDB handles
4469 command line arguments. The first non-flag argument is always
4470 a program to debug, but the second non-flag argument may either
4471 be a corefile or a process id. Previously, GDB would attempt to
4472 open the second argument as a corefile, and if that failed, would
4473 issue a superfluous error message and then attempt to attach it as
4474 a process. Now, if the second argument begins with a non-digit,
4475 it will be treated as a corefile. If it begins with a digit,
4476 GDB will attempt to attach it as a process, and if no such process
4477 is found, will then attempt to open it as a corefile.
4479 * Changes in ARM configurations.
4481 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4482 configuration is fully multi-arch.
4484 * New native configurations
4486 ARM NetBSD arm*-*-netbsd*
4487 x86 OpenBSD i[3456]86-*-openbsd*
4488 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4489 Sparc64 running FreeBSD sparc64-*-freebsd*
4493 Sanyo XStormy16 xstormy16-elf
4495 * OBSOLETE configurations and files
4497 Configurations that have been declared obsolete in this release have
4498 been commented out. Unless there is activity to revive these
4499 configurations, the next release of GDB will have their sources
4500 permanently REMOVED.
4502 AMD 29k family via UDI a29k-amd-udi, udi29k
4503 A29K VxWorks a29k-*-vxworks
4504 AMD 29000 embedded, using EBMON a29k-none-none
4505 AMD 29000 embedded with COFF a29k-none-coff
4506 AMD 29000 embedded with a.out a29k-none-aout
4508 testsuite/gdb.hp/gdb.threads-hp/ directory
4510 * REMOVED configurations and files
4512 TI TMS320C80 tic80-*-*
4514 PowerPC Solaris powerpcle-*-solaris*
4515 PowerPC Windows NT powerpcle-*-cygwin32
4516 PowerPC Netware powerpc-*-netware*
4517 Harris/CXUX m88k m88*-harris-cxux*
4518 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4519 ns32k-utek-sysv* ns32k-utek-*
4520 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4521 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4522 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4523 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4524 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4526 * Changes to command line processing
4528 The new `--args' feature can be used to specify command-line arguments
4529 for the inferior from gdb's command line.
4531 * Changes to key bindings
4533 There is a new `operate-and-get-next' function bound to `C-o'.
4535 *** Changes in GDB 5.1.1
4537 Fix compile problem on DJGPP.
4539 Fix a problem with floating-point registers on the i386 being
4542 Fix to stop GDB crashing on .debug_str debug info.
4544 Numerous documentation fixes.
4546 Numerous testsuite fixes.
4548 *** Changes in GDB 5.1:
4550 * New native configurations
4552 Alpha FreeBSD alpha*-*-freebsd*
4553 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4554 MIPS GNU/Linux mips*-*-linux*
4555 MIPS SGI Irix 6.x mips*-sgi-irix6*
4556 ia64 AIX ia64-*-aix*
4557 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4561 Motorola 68HC11 and 68HC12 m68hc11-elf
4563 UltraSparc running GNU/Linux sparc64-*-linux*
4565 * OBSOLETE configurations and files
4567 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4568 Harris/CXUX m88k m88*-harris-cxux*
4569 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4570 ns32k-utek-sysv* ns32k-utek-*
4571 TI TMS320C80 tic80-*-*
4573 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4574 PowerPC Solaris powerpcle-*-solaris*
4575 PowerPC Windows NT powerpcle-*-cygwin32
4576 PowerPC Netware powerpc-*-netware*
4577 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4578 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4579 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4580 Apple Macintosh (MPW) host N/A
4582 stuff.c (Program to stuff files into a specially prepared space in kdb)
4583 kdb-start.c (Main loop for the standalone kernel debugger)
4585 Configurations that have been declared obsolete in this release have
4586 been commented out. Unless there is activity to revive these
4587 configurations, the next release of GDB will have their sources
4588 permanently REMOVED.
4590 * REMOVED configurations and files
4592 Altos 3068 m68*-altos-*
4593 Convex c1-*-*, c2-*-*
4595 ARM RISCix arm-*-* (as host)
4599 * GDB has been converted to ISO C.
4601 GDB's source code has been converted to ISO C. In particular, the
4602 sources are fully protoized, and rely on standard headers being
4607 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4609 * The MI enabled by default.
4611 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4612 revised and enabled by default. Packages which use GDB as a debugging
4613 engine behind a UI or another front end are encouraged to switch to
4614 using the GDB/MI interface, instead of the old annotations interface
4615 which is now deprecated.
4617 * Support for debugging Pascal programs.
4619 GDB now includes support for debugging Pascal programs. The following
4620 main features are supported:
4622 - Pascal-specific data types such as sets;
4624 - automatic recognition of Pascal sources based on file-name
4627 - Pascal-style display of data types, variables, and functions;
4629 - a Pascal expression parser.
4631 However, some important features are not yet supported.
4633 - Pascal string operations are not supported at all;
4635 - there are some problems with boolean types;
4637 - Pascal type hexadecimal constants are not supported
4638 because they conflict with the internal variables format;
4640 - support for Pascal objects and classes is not full yet;
4642 - unlike Pascal, GDB is case-sensitive for symbol names.
4644 * Changes in completion.
4646 Commands such as `shell', `run' and `set args', which pass arguments
4647 to inferior programs, now complete on file names, similar to what
4648 users expect at the shell prompt.
4650 Commands which accept locations, such as `disassemble', `print',
4651 `breakpoint', `until', etc. now complete on filenames as well as
4652 program symbols. Thus, if you type "break foob TAB", and the source
4653 files linked into the programs include `foobar.c', that file name will
4654 be one of the candidates for completion. However, file names are not
4655 considered for completion after you typed a colon that delimits a file
4656 name from a name of a function in that file, as in "break foo.c:bar".
4658 `set demangle-style' completes on available demangling styles.
4660 * New platform-independent commands:
4662 It is now possible to define a post-hook for a command as well as a
4663 hook that runs before the command. For more details, see the
4664 documentation of `hookpost' in the GDB manual.
4666 * Changes in GNU/Linux native debugging.
4668 Support for debugging multi-threaded programs has been completely
4669 revised for all platforms except m68k and sparc. You can now debug as
4670 many threads as your system allows you to have.
4672 Attach/detach is supported for multi-threaded programs.
4674 Support for SSE registers was added for x86. This doesn't work for
4675 multi-threaded programs though.
4677 * Changes in MIPS configurations.
4679 Multi-arch support is enabled for all MIPS configurations.
4681 GDB can now be built as native debugger on SGI Irix 6.x systems for
4682 debugging n32 executables. (Debugging 64-bit executables is not yet
4685 * Unified support for hardware watchpoints in all x86 configurations.
4687 Most (if not all) native x86 configurations support hardware-assisted
4688 breakpoints and watchpoints in a unified manner. This support
4689 implements debug register sharing between watchpoints, which allows to
4690 put a virtually infinite number of watchpoints on the same address,
4691 and also supports watching regions up to 16 bytes with several debug
4694 The new maintenance command `maintenance show-debug-regs' toggles
4695 debugging print-outs in functions that insert, remove, and test
4696 watchpoints and hardware breakpoints.
4698 * Changes in the DJGPP native configuration.
4700 New command ``info dos sysinfo'' displays assorted information about
4701 the CPU, OS, memory, and DPMI server.
4703 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4704 display information about segment descriptors stored in GDT, LDT, and
4707 New commands ``info dos pde'' and ``info dos pte'' display entries
4708 from Page Directory and Page Tables (for now works with CWSDPMI only).
4709 New command ``info dos address-pte'' displays the Page Table entry for
4710 a given linear address.
4712 GDB can now pass command lines longer than 126 characters to the
4713 program being debugged (requires an update to the libdbg.a library
4714 which is part of the DJGPP development kit).
4716 DWARF2 debug info is now supported.
4718 It is now possible to `step' and `next' through calls to `longjmp'.
4720 * Changes in documentation.
4722 All GDB documentation was converted to GFDL, the GNU Free
4723 Documentation License.
4725 Tracepoints-related commands are now fully documented in the GDB
4728 TUI, the Text-mode User Interface, is now documented in the manual.
4730 Tracepoints-related commands are now fully documented in the GDB
4733 The "GDB Internals" manual now has an index. It also includes
4734 documentation of `ui_out' functions, GDB coding standards, x86
4735 hardware watchpoints, and memory region attributes.
4737 * GDB's version number moved to ``version.in''
4739 The Makefile variable VERSION has been replaced by the file
4740 ``version.in''. People creating GDB distributions should update the
4741 contents of this file.
4745 GUD support is now a standard part of the EMACS distribution.
4747 *** Changes in GDB 5.0:
4749 * Improved support for debugging FP programs on x86 targets
4751 Unified and much-improved support for debugging floating-point
4752 programs on all x86 targets. In particular, ``info float'' now
4753 displays the FP registers in the same format on all x86 targets, with
4754 greater level of detail.
4756 * Improvements and bugfixes in hardware-assisted watchpoints
4758 It is now possible to watch array elements, struct members, and
4759 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4760 on x86 targets no longer erroneously trigger when the address is
4763 * Improvements in the native DJGPP version of GDB
4765 The distribution now includes all the scripts and auxiliary files
4766 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4767 machines ``out of the box''.
4769 The DJGPP version can now debug programs that use signals. It is
4770 possible to catch signals that happened in the debuggee, deliver
4771 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4772 would kill the program being debugged.) Programs that hook hardware
4773 interrupts (keyboard, timer, etc.) can also be debugged.
4775 It is now possible to debug DJGPP programs that redirect their
4776 standard handles or switch them to raw (as opposed to cooked) mode, or
4777 even close them. The command ``run < foo > bar'' works as expected,
4778 and ``info terminal'' reports useful information about the debuggee's
4779 terminal, including raw/cooked mode, redirection, etc.
4781 The DJGPP version now uses termios functions for console I/O, which
4782 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4785 DOS-style file names with drive letters are now fully supported by
4788 It is now possible to debug DJGPP programs that switch their working
4789 directory. It is also possible to rerun the debuggee any number of
4790 times without restarting GDB; thus, you can use the same setup,
4791 breakpoints, etc. for many debugging sessions.
4793 * New native configurations
4795 ARM GNU/Linux arm*-*-linux*
4796 PowerPC GNU/Linux powerpc-*-linux*
4800 Motorola MCore mcore-*-*
4801 x86 VxWorks i[3456]86-*-vxworks*
4802 PowerPC VxWorks powerpc-*-vxworks*
4803 TI TMS320C80 tic80-*-*
4805 * OBSOLETE configurations
4807 Altos 3068 m68*-altos-*
4808 Convex c1-*-*, c2-*-*
4810 ARM RISCix arm-*-* (as host)
4813 Configurations that have been declared obsolete will be commented out,
4814 but the code will be left in place. If there is no activity to revive
4815 these configurations before the next release of GDB, the sources will
4816 be permanently REMOVED.
4818 * Gould support removed
4820 Support for the Gould PowerNode and NP1 has been removed.
4822 * New features for SVR4
4824 On SVR4 native platforms (such as Solaris), if you attach to a process
4825 without first loading a symbol file, GDB will now attempt to locate and
4826 load symbols from the running process's executable file.
4828 * Many C++ enhancements
4830 C++ support has been greatly improved. Overload resolution now works properly
4831 in almost all cases. RTTI support is on the way.
4833 * Remote targets can connect to a sub-program
4835 A popen(3) style serial-device has been added. This device starts a
4836 sub-process (such as a stand-alone simulator) and then communicates
4837 with that. The sub-program to run is specified using the syntax
4838 ``|<program> <args>'' vis:
4840 (gdb) set remotedebug 1
4841 (gdb) target extended-remote |mn10300-elf-sim program-args
4843 * MIPS 64 remote protocol
4845 A long standing bug in the mips64 remote protocol where by GDB
4846 expected certain 32 bit registers (ex SR) to be transfered as 32
4847 instead of 64 bits has been fixed.
4849 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4850 added to provide backward compatibility with older versions of GDB.
4852 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4854 The command ``set remotebinarydownload'' command has been replaced by
4855 ``set remote X-packet''. Other commands in ``set remote'' family
4856 include ``set remote P-packet''.
4858 * Breakpoint commands accept ranges.
4860 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4861 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4862 ``tracepoint passcount'' also accepts a range of tracepoints.
4864 * ``apropos'' command added.
4866 The ``apropos'' command searches through command names and
4867 documentation strings, printing out matches, making it much easier to
4868 try to find a command that does what you are looking for.
4872 A new machine oriented interface (MI) has been added to GDB. This
4873 interface is designed for debug environments running GDB as a separate
4874 process. This is part of the long term libGDB project. See the
4875 "GDB/MI" chapter of the GDB manual for further information. It can be
4876 enabled by configuring with:
4878 .../configure --enable-gdbmi
4880 *** Changes in GDB-4.18:
4882 * New native configurations
4884 HP-UX 10.20 hppa*-*-hpux10.20
4885 HP-UX 11.x hppa*-*-hpux11.0*
4886 M68K GNU/Linux m68*-*-linux*
4890 Fujitsu FR30 fr30-*-elf*
4891 Intel StrongARM strongarm-*-*
4892 Mitsubishi D30V d30v-*-*
4894 * OBSOLETE configurations
4896 Gould PowerNode, NP1 np1-*-*, pn-*-*
4898 Configurations that have been declared obsolete will be commented out,
4899 but the code will be left in place. If there is no activity to revive
4900 these configurations before the next release of GDB, the sources will
4901 be permanently REMOVED.
4905 As a compatibility experiment, GDB's source files buildsym.h and
4906 buildsym.c have been converted to pure standard C, no longer
4907 containing any K&R compatibility code. We believe that all systems in
4908 use today either come with a standard C compiler, or have a GCC port
4909 available. If this is not true, please report the affected
4910 configuration to bug-gdb@gnu.org immediately. See the README file for
4911 information about getting a standard C compiler if you don't have one
4916 GDB now uses readline 2.2.
4918 * set extension-language
4920 You can now control the mapping between filename extensions and source
4921 languages by using the `set extension-language' command. For instance,
4922 you can ask GDB to treat .c files as C++ by saying
4923 set extension-language .c c++
4924 The command `info extensions' lists all of the recognized extensions
4925 and their associated languages.
4927 * Setting processor type for PowerPC and RS/6000
4929 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4930 you can use the `set processor' command to specify what variant of the
4931 PowerPC family you are debugging. The command
4935 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4936 following PowerPC and RS6000 variants:
4938 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4939 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4941 403GC IBM PowerPC 403GC
4942 505 Motorola PowerPC 505
4943 860 Motorola PowerPC 860 or 850
4944 601 Motorola PowerPC 601
4945 602 Motorola PowerPC 602
4946 603 Motorola/IBM PowerPC 603 or 603e
4947 604 Motorola PowerPC 604 or 604e
4948 750 Motorola/IBM PowerPC 750 or 750
4950 At the moment, this command just tells GDB what to name the
4951 special-purpose processor registers. Since almost all the affected
4952 registers are inaccessible to user-level programs, this command is
4953 only useful for remote debugging in its present form.
4957 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4958 more extensive support for HP-UX. Added features include shared
4959 library support, kernel threads and hardware watchpoints for 11.00,
4960 support for HP's ANSI C and C++ compilers, and a compatibility mode
4961 for xdb and dbx commands.
4965 HP's donation includes the new concept of catchpoints, which is a
4966 generalization of the old catch command. On HP-UX, it is now possible
4967 to catch exec, fork, and vfork, as well as library loading.
4969 This means that the existing catch command has changed; its first
4970 argument now specifies the type of catch to be set up. See the
4971 output of "help catch" for a list of catchpoint types.
4973 * Debugging across forks
4975 On HP-UX, you can choose which process to debug when a fork() happens
4980 HP has donated a curses-based terminal user interface (TUI). To get
4981 it, build with --enable-tui. Although this can be enabled for any
4982 configuration, at present it only works for native HP debugging.
4984 * GDB remote protocol additions
4986 A new protocol packet 'X' that writes binary data is now available.
4987 Default behavior is to try 'X', then drop back to 'M' if the stub
4988 fails to respond. The settable variable `remotebinarydownload'
4989 allows explicit control over the use of 'X'.
4991 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4992 full 64-bit address. The command
4994 set remoteaddresssize 32
4996 can be used to revert to the old behaviour. For existing remote stubs
4997 the change should not be noticed, as the additional address information
5000 In order to assist in debugging stubs, you may use the maintenance
5001 command `packet' to send any text string to the stub. For instance,
5003 maint packet heythere
5005 sends the packet "$heythere#<checksum>". Note that it is very easy to
5006 disrupt a debugging session by sending the wrong packet at the wrong
5009 The compare-sections command allows you to compare section data on the
5010 target to what is in the executable file without uploading or
5011 downloading, by comparing CRC checksums.
5013 * Tracing can collect general expressions
5015 You may now collect general expressions at tracepoints. This requires
5016 further additions to the target-side stub; see tracepoint.c and
5017 doc/agentexpr.texi for further details.
5019 * mask-address variable for Mips
5021 For Mips targets, you may control the zeroing of the upper 32 bits of
5022 a 64-bit address by entering `set mask-address on'. This is mainly
5023 of interest to users of embedded R4xxx and R5xxx processors.
5025 * Higher serial baud rates
5027 GDB's serial code now allows you to specify baud rates 57600, 115200,
5028 230400, and 460800 baud. (Note that your host system may not be able
5029 to achieve all of these rates.)
5033 The i960 configuration now includes an initial implementation of a
5034 builtin simulator, contributed by Jim Wilson.
5037 *** Changes in GDB-4.17:
5039 * New native configurations
5041 Alpha GNU/Linux alpha*-*-linux*
5042 Unixware 2.x i[3456]86-unixware2*
5043 Irix 6.x mips*-sgi-irix6*
5044 PowerPC GNU/Linux powerpc-*-linux*
5045 PowerPC Solaris powerpcle-*-solaris*
5046 Sparc GNU/Linux sparc-*-linux*
5047 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5051 Argonaut Risc Chip (ARC) arc-*-*
5052 Hitachi H8/300S h8300*-*-*
5053 Matsushita MN10200 w/simulator mn10200-*-*
5054 Matsushita MN10300 w/simulator mn10300-*-*
5055 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5056 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5057 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5058 Mitsubishi D10V w/simulator d10v-*-*
5059 Mitsubishi M32R/D w/simulator m32r-*-elf*
5060 Tsqware Sparclet sparclet-*-*
5061 NEC V850 w/simulator v850-*-*
5063 * New debugging protocols
5065 ARM with RDI protocol arm*-*-*
5066 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5067 DDB and LSI variants of PMON protocol mips*-*-*
5068 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5069 PowerPC with SDS protocol powerpc{,le}-*-eabi
5070 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5074 All configurations can now understand and use the DWARF 2 debugging
5075 format. The choice is automatic, if the symbol file contains DWARF 2
5080 GDB now includes basic Java language support. This support is
5081 only useful with Java compilers that produce native machine code.
5083 * solib-absolute-prefix and solib-search-path
5085 For SunOS and SVR4 shared libraries, you may now set the prefix for
5086 loading absolute shared library symbol files, and the search path for
5087 locating non-absolute shared library symbol files.
5089 * Live range splitting
5091 GDB can now effectively debug code for which GCC has performed live
5092 range splitting as part of its optimization. See gdb/doc/LRS for
5093 more details on the expected format of the stabs information.
5097 GDB's support for the GNU Hurd, including thread debugging, has been
5098 updated to work with current versions of the Hurd.
5102 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5103 instruction set. ARM GDB automatically detects when Thumb
5104 instructions are in use, and adjusts disassembly and backtracing
5109 GDB's MIPS target configurations now handle the MIP16 16-bit
5114 GDB now includes support for overlays; if an executable has been
5115 linked such that multiple sections are based at the same address, GDB
5116 will decide which section to use for symbolic info. You can choose to
5117 control the decision manually, using overlay commands, or implement
5118 additional target-side support and use "overlay load-target" to bring
5119 in the overlay mapping. Do "help overlay" for more detail.
5123 The command "info symbol <address>" displays information about
5124 the symbol at the specified address.
5128 The standard remote protocol now includes an extension that allows
5129 asynchronous collection and display of trace data. This requires
5130 extensive support in the target-side debugging stub. Tracing mode
5131 includes a new interaction mode in GDB and new commands: see the
5132 file tracepoint.c for more details.
5136 Configurations for embedded MIPS now include a simulator contributed
5137 by Cygnus Solutions. The simulator supports the instruction sets
5138 of most MIPS variants.
5142 Sparc configurations may now include the ERC32 simulator contributed
5143 by the European Space Agency. The simulator is not built into
5144 Sparc targets by default; configure with --enable-sim to include it.
5148 For target configurations that may include multiple variants of a
5149 basic architecture (such as MIPS and SH), you may now set the
5150 architecture explicitly. "set arch" sets, "info arch" lists
5151 the possible architectures.
5153 *** Changes in GDB-4.16:
5155 * New native configurations
5157 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5158 M68K NetBSD m68k-*-netbsd*
5159 PowerPC AIX 4.x powerpc-*-aix*
5160 PowerPC MacOS powerpc-*-macos*
5161 PowerPC Windows NT powerpcle-*-cygwin32
5162 RS/6000 AIX 4.x rs6000-*-aix4*
5166 ARM with RDP protocol arm-*-*
5167 I960 with MON960 i960-*-coff
5168 MIPS VxWorks mips*-*-vxworks*
5169 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5170 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5172 Matra Sparclet sparclet-*-*
5176 The powerpc-eabi configuration now includes the PSIM simulator,
5177 contributed by Andrew Cagney, with assistance from Mike Meissner.
5178 PSIM is a very elaborate model of the PowerPC, including not only
5179 basic instruction set execution, but also details of execution unit
5180 performance and I/O hardware. See sim/ppc/README for more details.
5184 GDB now works with Solaris 2.5.
5186 * Windows 95/NT native
5188 GDB will now work as a native debugger on Windows 95 and Windows NT.
5189 To build it from source, you must use the "gnu-win32" environment,
5190 which uses a DLL to emulate enough of Unix to run the GNU tools.
5191 Further information, binaries, and sources are available at
5192 ftp.cygnus.com, under pub/gnu-win32.
5194 * dont-repeat command
5196 If a user-defined command includes the command `dont-repeat', then the
5197 command will not be repeated if the user just types return. This is
5198 useful if the command is time-consuming to run, so that accidental
5199 extra keystrokes don't run the same command many times.
5201 * Send break instead of ^C
5203 The standard remote protocol now includes an option to send a break
5204 rather than a ^C to the target in order to interrupt it. By default,
5205 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5207 * Remote protocol timeout
5209 The standard remote protocol includes a new variable `remotetimeout'
5210 that allows you to set the number of seconds before GDB gives up trying
5211 to read from the target. The default value is 2.
5213 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5215 By default GDB will automatically keep track of objects as they are
5216 loaded and unloaded by the dynamic linker. By using the command `set
5217 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5218 when shared library events occur, thus allowing you to set breakpoints
5219 in shared libraries which are explicitly loaded by the inferior.
5221 Note this feature does not work on hpux8. On hpux9 you must link
5222 /usr/lib/end.o into your program. This feature should work
5223 automatically on hpux10.
5225 * Irix 5.x hardware watchpoint support
5227 Irix 5 configurations now support the use of hardware watchpoints.
5229 * Mips protocol "SYN garbage limit"
5231 When debugging a Mips target using the `target mips' protocol, you
5232 may set the number of characters that GDB will ignore by setting
5233 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5234 every character. The default value is 1050.
5236 * Recording and replaying remote debug sessions
5238 If you set `remotelogfile' to the name of a file, gdb will write to it
5239 a recording of a remote debug session. This recording may then be
5240 replayed back to gdb using "gdbreplay". See gdbserver/README for
5241 details. This is useful when you have a problem with GDB while doing
5242 remote debugging; you can make a recording of the session and send it
5243 to someone else, who can then recreate the problem.
5245 * Speedups for remote debugging
5247 GDB includes speedups for downloading and stepping MIPS systems using
5248 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5249 and more efficient S-record downloading.
5251 * Memory use reductions and statistics collection
5253 GDB now uses less memory and reports statistics about memory usage.
5254 Try the `maint print statistics' command, for example.
5256 *** Changes in GDB-4.15:
5258 * Psymtabs for XCOFF
5260 The symbol reader for AIX GDB now uses partial symbol tables. This
5261 can greatly improve startup time, especially for large executables.
5263 * Remote targets use caching
5265 Remote targets now use a data cache to speed up communication with the
5266 remote side. The data cache could lead to incorrect results because
5267 it doesn't know about volatile variables, thus making it impossible to
5268 debug targets which use memory mapped I/O devices. `set remotecache
5269 off' turns the the data cache off.
5271 * Remote targets may have threads
5273 The standard remote protocol now includes support for multiple threads
5274 in the target system, using new protocol commands 'H' and 'T'. See
5275 gdb/remote.c for details.
5279 If GDB is configured with `--enable-netrom', then it will include
5280 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5281 acts as though it is a bank of ROM on the target board, but you can
5282 write into it over the network. GDB's support consists only of
5283 support for fast loading into the emulated ROM; to debug, you must use
5284 another protocol, such as standard remote protocol. The usual
5285 sequence is something like
5287 target nrom <netrom-hostname>
5289 target remote <netrom-hostname>:1235
5293 GDB now includes support for the Apple Macintosh, as a host only. It
5294 may be run as either an MPW tool or as a standalone application, and
5295 it can debug through the serial port. All the usual GDB commands are
5296 available, but to the target command, you must supply "serial" as the
5297 device type instead of "/dev/ttyXX". See mpw-README in the main
5298 directory for more information on how to build. The MPW configuration
5299 scripts */mpw-config.in support only a few targets, and only the
5300 mips-idt-ecoff target has been tested.
5304 GDB configuration now uses autoconf. This is not user-visible,
5305 but does simplify configuration and building.
5309 GDB now supports hpux10.
5311 *** Changes in GDB-4.14:
5313 * New native configurations
5315 x86 FreeBSD i[345]86-*-freebsd
5316 x86 NetBSD i[345]86-*-netbsd
5317 NS32k NetBSD ns32k-*-netbsd
5318 Sparc NetBSD sparc-*-netbsd
5322 A29K VxWorks a29k-*-vxworks
5323 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5324 CPU32 EST-300 emulator m68*-*-est*
5325 PowerPC ELF powerpc-*-elf
5328 * Alpha OSF/1 support for procfs
5330 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5331 possible to attach to running processes. As the mounting of the /proc
5332 filesystem is optional on the Alpha, GDB automatically determines
5333 the availability of /proc during startup. This can lead to problems
5334 if /proc is unmounted after GDB has been started.
5336 * Arguments to user-defined commands
5338 User commands may accept up to 10 arguments separated by whitespace.
5339 Arguments are accessed within the user command via $arg0..$arg9. A
5342 print $arg0 + $arg1 + $arg2
5344 To execute the command use:
5347 Defines the command "adder" which prints the sum of its three arguments.
5348 Note the arguments are text substitutions, so they may reference variables,
5349 use complex expressions, or even perform inferior function calls.
5351 * New `if' and `while' commands
5353 This makes it possible to write more sophisticated user-defined
5354 commands. Both commands take a single argument, which is the
5355 expression to evaluate, and must be followed by the commands to
5356 execute, one per line, if the expression is nonzero, the list being
5357 terminated by the word `end'. The `if' command list may include an
5358 `else' word, which causes the following commands to be executed only
5359 if the expression is zero.
5361 * Fortran source language mode
5363 GDB now includes partial support for Fortran 77. It will recognize
5364 Fortran programs and can evaluate a subset of Fortran expressions, but
5365 variables and functions may not be handled correctly. GDB will work
5366 with G77, but does not yet know much about symbols emitted by other
5369 * Better HPUX support
5371 Most debugging facilities now work on dynamic executables for HPPAs
5372 running hpux9 or later. You can attach to running dynamically linked
5373 processes, but by default the dynamic libraries will be read-only, so
5374 for instance you won't be able to put breakpoints in them. To change
5375 that behavior do the following before running the program:
5381 This will cause the libraries to be mapped private and read-write.
5382 To revert to the normal behavior, do this:
5388 You cannot set breakpoints or examine data in the library until after
5389 the library is loaded if the function/data symbols do not have
5392 GDB can now also read debug symbols produced by the HP C compiler on
5393 HPPAs (sorry, no C++, Fortran or 68k support).
5395 * Target byte order now dynamically selectable
5397 You can choose which byte order to use with a target system, via the
5398 commands "set endian big" and "set endian little", and you can see the
5399 current setting by using "show endian". You can also give the command
5400 "set endian auto", in which case GDB will use the byte order
5401 associated with the executable. Currently, only embedded MIPS
5402 configurations support dynamic selection of target byte order.
5404 * New DOS host serial code
5406 This version uses DPMI interrupts to handle buffered I/O, so you
5407 no longer need to run asynctsr when debugging boards connected to
5410 *** Changes in GDB-4.13:
5412 * New "complete" command
5414 This lists all the possible completions for the rest of the line, if it
5415 were to be given as a command itself. This is intended for use by emacs.
5417 * Trailing space optional in prompt
5419 "set prompt" no longer adds a space for you after the prompt you set. This
5420 allows you to set a prompt which ends in a space or one that does not.
5422 * Breakpoint hit counts
5424 "info break" now displays a count of the number of times the breakpoint
5425 has been hit. This is especially useful in conjunction with "ignore"; you
5426 can ignore a large number of breakpoint hits, look at the breakpoint info
5427 to see how many times the breakpoint was hit, then run again, ignoring one
5428 less than that number, and this will get you quickly to the last hit of
5431 * Ability to stop printing at NULL character
5433 "set print null-stop" will cause GDB to stop printing the characters of
5434 an array when the first NULL is encountered. This is useful when large
5435 arrays actually contain only short strings.
5437 * Shared library breakpoints
5439 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5440 breakpoints in shared libraries before the executable is run.
5442 * Hardware watchpoints
5444 There is a new hardware breakpoint for the watch command for sparclite
5445 targets. See gdb/sparclite/hw_breakpoint.note.
5447 Hardware watchpoints are also now supported under GNU/Linux.
5451 Annotations have been added. These are for use with graphical interfaces,
5452 and are still experimental. Currently only gdba.el uses these.
5454 * Improved Irix 5 support
5456 GDB now works properly with Irix 5.2.
5458 * Improved HPPA support
5460 GDB now works properly with the latest GCC and GAS.
5462 * New native configurations
5464 Sequent PTX4 i[34]86-sequent-ptx4
5465 HPPA running OSF/1 hppa*-*-osf*
5466 Atari TT running SVR4 m68*-*-sysv4*
5467 RS/6000 LynxOS rs6000-*-lynxos*
5471 OS/9000 i[34]86-*-os9k
5472 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5475 * Hitachi SH7000 and E7000-PC ICE support
5477 There is now support for communicating with the Hitachi E7000-PC ICE.
5478 This is available automatically when GDB is configured for the SH.
5482 As usual, a variety of small fixes and improvements, both generic
5483 and configuration-specific. See the ChangeLog for more detail.
5485 *** Changes in GDB-4.12:
5487 * Irix 5 is now supported
5491 GDB-4.12 on the HPPA has a number of changes which make it unable
5492 to debug the output from the currently released versions of GCC and
5493 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5494 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5495 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5498 *** Changes in GDB-4.11:
5500 * User visible changes:
5504 The "set remotedebug" option is now consistent between the mips remote
5505 target, remote targets using the gdb-specific protocol, UDI (AMD's
5506 debug protocol for the 29k) and the 88k bug monitor. It is now an
5507 integer specifying a debug level (normally 0 or 1, but 2 means more
5508 debugging info for the mips target).
5510 * DEC Alpha native support
5512 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5513 debug info, but GDB works fairly well with the DEC compiler and should
5514 work with a future GCC release. See the README file for a few
5515 Alpha-specific notes.
5517 * Preliminary thread implementation
5519 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5521 * LynxOS native and target support for 386
5523 This release has been hosted on LynxOS 2.2, and also can be configured
5524 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5527 * Improvements in C++ mangling/demangling.
5529 This release has much better g++ debugging, specifically in name
5530 mangling/demangling, virtual function calls, print virtual table,
5531 call methods, ...etc.
5533 *** Changes in GDB-4.10:
5535 * User visible changes:
5537 Remote debugging using the GDB-specific (`target remote') protocol now
5538 supports the `load' command. This is only useful if you have some
5539 other way of getting the stub to the target system, and you can put it
5540 somewhere in memory where it won't get clobbered by the download.
5542 Filename completion now works.
5544 When run under emacs mode, the "info line" command now causes the
5545 arrow to point to the line specified. Also, "info line" prints
5546 addresses in symbolic form (as well as hex).
5548 All vxworks based targets now support a user settable option, called
5549 vxworks-timeout. This option represents the number of seconds gdb
5550 should wait for responses to rpc's. You might want to use this if
5551 your vxworks target is, perhaps, a slow software simulator or happens
5552 to be on the far side of a thin network line.
5556 This release contains support for using a DEC alpha as a GDB host for
5557 cross debugging. Native alpha debugging is not supported yet.
5560 *** Changes in GDB-4.9:
5564 This is the first GDB release which is accompanied by a matching testsuite.
5565 The testsuite requires installation of dejagnu, which should be available
5566 via ftp from most sites that carry GNU software.
5570 'Cfront' style demangling has had its name changed to 'ARM' style, to
5571 emphasize that it was written from the specifications in the C++ Annotated
5572 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5573 disclaimers, it still generated too much confusion with users attempting to
5574 use gdb with AT&T cfront.
5578 GDB now uses a standard remote interface to a simulator library.
5579 So far, the library contains simulators for the Zilog Z8001/2, the
5580 Hitachi H8/300, H8/500 and Super-H.
5582 * New targets supported
5584 H8/300 simulator h8300-hitachi-hms or h8300hms
5585 H8/500 simulator h8500-hitachi-hms or h8500hms
5586 SH simulator sh-hitachi-hms or sh
5587 Z8000 simulator z8k-zilog-none or z8ksim
5588 IDT MIPS board over serial line mips-idt-ecoff
5590 Cross-debugging to GO32 targets is supported. It requires a custom
5591 version of the i386-stub.c module which is integrated with the
5592 GO32 memory extender.
5594 * New remote protocols
5596 MIPS remote debugging protocol.
5598 * New source languages supported
5600 This version includes preliminary support for Chill, a Pascal like language
5601 used by telecommunications companies. Chill support is also being integrated
5602 into the GNU compiler, but we don't know when it will be publically available.
5605 *** Changes in GDB-4.8:
5607 * HP Precision Architecture supported
5609 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5610 version of this support was available as a set of patches from the
5611 University of Utah. GDB does not support debugging of programs
5612 compiled with the HP compiler, because HP will not document their file
5613 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5614 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5616 Many problems in the preliminary version have been fixed.
5618 * Faster and better demangling
5620 We have improved template demangling and fixed numerous bugs in the GNU style
5621 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5622 character types (wchar_t) are now supported. Demangling of each symbol is now
5623 only done once, and is cached when the symbol table for a file is read in.
5624 This results in a small increase in memory usage for C programs, a moderate
5625 increase in memory usage for C++ programs, and a fantastic speedup in
5628 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5629 from the specifications in the Annotated Reference Manual, which AT&T's
5630 compiler does not actually implement.
5632 * G++ multiple inheritance compiler problem
5634 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5635 inheritance lattices was reworked to properly discover ambiguities. We
5636 recently found an example which causes this new algorithm to fail in a
5637 very subtle way, producing bad debug information for those classes.
5638 The file 'gcc.patch' (in this directory) can be applied to gcc to
5639 circumvent the problem. A future GCC release will contain a complete
5642 The previous G++ debug info problem (mentioned below for the gdb-4.7
5643 release) is fixed in gcc version 2.3.2.
5645 * Improved configure script
5647 The `configure' script will now attempt to guess your system type if
5648 you don't supply a host system type. The old scheme of supplying a
5649 host system triplet is preferable over using this. All the magic is
5650 done in the new `config.guess' script. Examine it for details.
5652 We have also brought our configure script much more in line with the FSF's
5653 version. It now supports the --with-xxx options. In particular,
5654 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5655 The resulting GDB will not be able to read arbitrary object file formats --
5656 only the format ``expected'' to be used on the configured target system.
5657 We hope to make this the default in a future release.
5659 * Documentation improvements
5661 There's new internal documentation on how to modify GDB, and how to
5662 produce clean changes to the code. We implore people to read it
5663 before submitting changes.
5665 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5666 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5667 `info' files are also provided. To build `info' files from scratch,
5668 you will need the latest `makeinfo' release, which will be available in
5669 a future texinfo-X.Y release.
5671 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5672 We're not sure exactly which versions have this problem, but it has
5673 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5674 or better. If that isn't possible, there is a patch in
5675 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5676 around this problem.
5680 GDB now supports array constants that can be used in expressions typed in by
5681 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5682 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5685 The new directory `gdb/sparclite' contains a program that demonstrates
5686 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5688 * New native hosts supported
5690 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5691 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5693 * New targets supported
5695 AMD 29k family via UDI a29k-amd-udi or udi29k
5697 * New file formats supported
5699 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5700 HPUX core files, and SCO 3.2v2 core files.
5704 Attaching to processes now works again; thanks for the many bug reports.
5706 We have also stomped on a bunch of core dumps caused by
5707 printf_filtered("%s") problems.
5709 We eliminated a copyright problem on the rpc and ptrace header files
5710 for VxWorks, which was discovered at the last minute during the 4.7
5711 release. You should now be able to build a VxWorks GDB.
5713 You can now interrupt gdb while an attached process is running. This
5714 will cause the attached process to stop, and give control back to GDB.
5716 We fixed problems caused by using too many file descriptors
5717 for reading symbols from object files and libraries. This was
5718 especially a problem for programs that used many (~100) shared
5721 The `step' command now only enters a subroutine if there is line number
5722 information for the subroutine. Otherwise it acts like the `next'
5723 command. Previously, `step' would enter subroutines if there was
5724 any debugging information about the routine. This avoids problems
5725 when using `cc -g1' on MIPS machines.
5727 * Internal improvements
5729 GDB's internal interfaces have been improved to make it easier to support
5730 debugging of multiple languages in the future.
5732 GDB now uses a common structure for symbol information internally.
5733 Minimal symbols (derived from linkage symbols in object files), partial
5734 symbols (from a quick scan of debug information), and full symbols
5735 contain a common subset of information, making it easier to write
5736 shared code that handles any of them.
5738 * New command line options
5740 We now accept --silent as an alias for --quiet.
5744 The memory-mapped-malloc library is now licensed under the GNU Library
5745 General Public License.
5747 *** Changes in GDB-4.7:
5749 * Host/native/target split
5751 GDB has had some major internal surgery to untangle the support for
5752 hosts and remote targets. Now, when you configure GDB for a remote
5753 target, it will no longer load in all of the support for debugging
5754 local programs on the host. When fully completed and tested, this will
5755 ensure that arbitrary host/target combinations are possible.
5757 The primary conceptual shift is to separate the non-portable code in
5758 GDB into three categories. Host specific code is required any time GDB
5759 is compiled on that host, regardless of the target. Target specific
5760 code relates to the peculiarities of the target, but can be compiled on
5761 any host. Native specific code is everything else: it can only be
5762 built when the host and target are the same system. Child process
5763 handling and core file support are two common `native' examples.
5765 GDB's use of /proc for controlling Unix child processes is now cleaner.
5766 It has been split out into a single module under the `target_ops' vector,
5767 plus two native-dependent functions for each system that uses /proc.
5769 * New hosts supported
5771 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5772 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5773 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5775 * New targets supported
5777 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5778 68030 and CPU32 m68030-*-*, m68332-*-*
5780 * New native hosts supported
5782 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5783 (386bsd is not well tested yet)
5784 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5786 * New file formats supported
5788 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5789 supports reading of `a.out.adobe' object files, which are an a.out
5790 format extended with minimal information about multiple sections.
5794 `show copying' is the same as the old `info copying'.
5795 `show warranty' is the same as `info warrantee'.
5796 These were renamed for consistency. The old commands continue to work.
5798 `info handle' is a new alias for `info signals'.
5800 You can now define pre-command hooks, which attach arbitrary command
5801 scripts to any command. The commands in the hook will be executed
5802 prior to the user's command. You can also create a hook which will be
5803 executed whenever the program stops. See gdb.texinfo.
5807 We now deal with Cfront style name mangling, and can even extract type
5808 info from mangled symbols. GDB can automatically figure out which
5809 symbol mangling style your C++ compiler uses.
5811 Calling of methods and virtual functions has been improved as well.
5815 The crash that occured when debugging Sun Ansi-C compiled binaries is
5816 fixed. This was due to mishandling of the extra N_SO stabs output
5819 We also finally got Ultrix 4.2 running in house, and fixed core file
5820 support, with help from a dozen people on the net.
5822 John M. Farrell discovered that the reason that single-stepping was so
5823 slow on all of the Mips based platforms (primarily SGI and DEC) was
5824 that we were trying to demangle and lookup a symbol used for internal
5825 purposes on every instruction that was being stepped through. Changing
5826 the name of that symbol so that it couldn't be mistaken for a C++
5827 mangled symbol sped things up a great deal.
5829 Rich Pixley sped up symbol lookups in general by getting much smarter
5830 about when C++ symbol mangling is necessary. This should make symbol
5831 completion (TAB on the command line) much faster. It's not as fast as
5832 we'd like, but it's significantly faster than gdb-4.6.
5836 A new user controllable variable 'call_scratch_address' can
5837 specify the location of a scratch area to be used when GDB
5838 calls a function in the target. This is necessary because the
5839 usual method of putting the scratch area on the stack does not work
5840 in systems that have separate instruction and data spaces.
5842 We integrated changes to support the 29k UDI (Universal Debugger
5843 Interface), but discovered at the last minute that we didn't have all
5844 of the appropriate copyright paperwork. We are working with AMD to
5845 resolve this, and hope to have it available soon.
5849 We have sped up the remote serial line protocol, especially for targets
5850 with lots of registers. It now supports a new `expedited status' ('T')
5851 message which can be used in place of the existing 'S' status message.
5852 This allows the remote stub to send only the registers that GDB
5853 needs to make a quick decision about single-stepping or conditional
5854 breakpoints, eliminating the need to fetch the entire register set for
5855 each instruction being stepped through.
5857 The GDB remote serial protocol now implements a write-through cache for
5858 registers, only re-reading the registers if the target has run.
5860 There is also a new remote serial stub for SPARC processors. You can
5861 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5862 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5863 processor with a serial port.
5867 Configure.in files have become much easier to read and modify. A new
5868 `table driven' format makes it more obvious what configurations are
5869 supported, and what files each one uses.
5873 There is a new opcodes library which will eventually contain all of the
5874 disassembly routines and opcode tables. At present, it only contains
5875 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5876 disassembler (binutils/objdump) to share these routines.
5878 The libiberty library is now copylefted under the GNU Library General
5879 Public License. This allows more liberal use, and was done so libg++
5880 can use it. This makes no difference to GDB, since the Library License
5881 grants all the rights from the General Public License.
5885 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5886 reference to the stabs symbol info used by the debugger. It is (as far
5887 as we know) the only published document on this fascinating topic. We
5888 encourage you to read it, compare it to the stabs information on your
5889 system, and send improvements on the document in general (to
5890 bug-gdb@prep.ai.mit.edu).
5892 And, of course, many bugs have been fixed.
5895 *** Changes in GDB-4.6:
5897 * Better support for C++ function names
5899 GDB now accepts as input the "demangled form" of C++ overloaded function
5900 names and member function names, and can do command completion on such names
5901 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5902 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5903 Make use of command completion, it is your friend.
5905 GDB also now accepts a variety of C++ mangled symbol formats. They are
5906 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5907 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5908 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5909 for the list of formats.
5911 * G++ symbol mangling problem
5913 Recent versions of gcc have a bug in how they emit debugging information for
5914 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5915 directory) can be applied to gcc to fix the problem. Alternatively, if you
5916 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5917 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5918 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5921 * New 'maintenance' command
5923 All of the commands related to hacking GDB internals have been moved out of
5924 the main command set, and now live behind the 'maintenance' command. This
5925 can also be abbreviated as 'mt'. The following changes were made:
5927 dump-me -> maintenance dump-me
5928 info all-breakpoints -> maintenance info breakpoints
5929 printmsyms -> maintenance print msyms
5930 printobjfiles -> maintenance print objfiles
5931 printpsyms -> maintenance print psymbols
5932 printsyms -> maintenance print symbols
5934 The following commands are new:
5936 maintenance demangle Call internal GDB demangler routine to
5937 demangle a C++ link name and prints the result.
5938 maintenance print type Print a type chain for a given symbol
5940 * Change to .gdbinit file processing
5942 We now read the $HOME/.gdbinit file before processing the argv arguments
5943 (e.g. reading symbol files or core files). This allows global parameters to
5944 be set, which will apply during the symbol reading. The ./.gdbinit is still
5945 read after argv processing.
5947 * New hosts supported
5949 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5951 GNU/Linux support i386-unknown-linux or linux
5953 We are also including code to support the HP/PA running BSD and HPUX. This
5954 is almost guaranteed not to work, as we didn't have time to test or build it
5955 for this release. We are including it so that the more adventurous (or
5956 masochistic) of you can play with it. We also had major problems with the
5957 fact that the compiler that we got from HP doesn't support the -g option.
5960 * New targets supported
5962 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5964 * More smarts about finding #include files
5966 GDB now remembers the compilation directory for all include files, and for
5967 all files from which C is generated (like yacc and lex sources). This
5968 greatly improves GDB's ability to find yacc/lex sources, and include files,
5969 especially if you are debugging your program from a directory different from
5970 the one that contains your sources.
5972 We also fixed a bug which caused difficulty with listing and setting
5973 breakpoints in include files which contain C code. (In the past, you had to
5974 try twice in order to list an include file that you hadn't looked at before.)
5976 * Interesting infernals change
5978 GDB now deals with arbitrary numbers of sections, where the symbols for each
5979 section must be relocated relative to that section's landing place in the
5980 target's address space. This work was needed to support ELF with embedded
5981 stabs used by Solaris-2.0.
5983 * Bug fixes (of course!)
5985 There have been loads of fixes for the following things:
5986 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5987 i960, stabs, DOS(GO32), procfs, etc...
5989 See the ChangeLog for details.
5991 *** Changes in GDB-4.5:
5993 * New machines supported (host and target)
5995 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5997 SGI Irix-4.x mips-sgi-irix4 or iris4
5999 * New malloc package
6001 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6002 Mmalloc is capable of handling mutiple heaps of memory. It is also
6003 capable of saving a heap to a file, and then mapping it back in later.
6004 This can be used to greatly speedup the startup of GDB by using a
6005 pre-parsed symbol table which lives in a mmalloc managed heap. For
6006 more details, please read mmalloc/mmalloc.texi.
6010 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6011 'help info proc' for details.
6013 * MIPS ecoff symbol table format
6015 The code that reads MIPS symbol table format is now supported on all hosts.
6016 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6019 * File name changes for MS-DOS
6021 Many files in the config directories have been renamed to make it easier to
6022 support GDB on MS-DOSe systems (which have very restrictive file name
6023 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6024 environment) is close to working but has some remaining problems. Note
6025 that debugging of DOS programs is not supported, due to limitations
6026 in the ``operating system'', but it can be used to host cross-debugging.
6028 * Cross byte order fixes
6030 Many fixes have been made to support cross debugging of Sparc and MIPS
6031 targets from hosts whose byte order differs.
6033 * New -mapped and -readnow options
6035 If memory-mapped files are available on your system through the 'mmap'
6036 system call, you can use the -mapped option on the `file' or
6037 `symbol-file' commands to cause GDB to write the symbols from your
6038 program into a reusable file. If the program you are debugging is
6039 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6040 Future GDB debugging sessions will notice the presence of this file,
6041 and will quickly map in symbol information from it, rather than reading
6042 the symbol table from the executable program. Using the '-mapped'
6043 option in a GDB `file' or `symbol-file' command has the same effect as
6044 starting GDB with the '-mapped' command-line option.
6046 You can cause GDB to read the entire symbol table immediately by using
6047 the '-readnow' option with any of the commands that load symbol table
6048 information (or on the GDB command line). This makes the command
6049 slower, but makes future operations faster.
6051 The -mapped and -readnow options are typically combined in order to
6052 build a `fred.syms' file that contains complete symbol information.
6053 A simple GDB invocation to do nothing but build a `.syms' file for future
6056 gdb -batch -nx -mapped -readnow programname
6058 The `.syms' file is specific to the host machine on which GDB is run.
6059 It holds an exact image of GDB's internal symbol table. It cannot be
6060 shared across multiple host platforms.
6062 * longjmp() handling
6064 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6065 siglongjmp() without losing control. This feature has not yet been ported to
6066 all systems. It currently works on many 386 platforms, all MIPS-based
6067 platforms (SGI, DECstation, etc), and Sun3/4.
6071 Preliminary work has been put in to support the new Solaris OS from Sun. At
6072 this time, it can control and debug processes, but it is not capable of
6077 As always, many many bug fixes. The major areas were with g++, and mipsread.
6078 People using the MIPS-based platforms should experience fewer mysterious
6079 crashes and trashed symbol tables.
6081 *** Changes in GDB-4.4:
6083 * New machines supported (host and target)
6085 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6087 BSD Reno on Vax vax-dec-bsd
6088 Ultrix on Vax vax-dec-ultrix
6090 * New machines supported (target)
6092 AMD 29000 embedded, using EBMON a29k-none-none
6096 GDB continues to improve its handling of C++. `References' work better.
6097 The demangler has also been improved, and now deals with symbols mangled as
6098 per the Annotated C++ Reference Guide.
6100 GDB also now handles `stabs' symbol information embedded in MIPS
6101 `ecoff' symbol tables. Since the ecoff format was not easily
6102 extensible to handle new languages such as C++, this appeared to be a
6103 good way to put C++ debugging info into MIPS binaries. This option
6104 will be supported in the GNU C compiler, version 2, when it is
6107 * New features for SVR4
6109 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6110 shared libraries. Debugging dynamically linked programs should present
6111 only minor differences from debugging statically linked programs.
6113 The `info proc' command will print out information about any process
6114 on an SVR4 system (including the one you are debugging). At the moment,
6115 it prints the address mappings of the process.
6117 If you bring up GDB on another SVR4 system, please send mail to
6118 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6120 * Better dynamic linking support in SunOS
6122 Reading symbols from shared libraries which contain debugging symbols
6123 now works properly. However, there remain issues such as automatic
6124 skipping of `transfer vector' code during function calls, which
6125 make it harder to debug code in a shared library, than to debug the
6126 same code linked statically.
6130 GDB is now using the latest `getopt' routines from the FSF. This
6131 version accepts the -- prefix for options with long names. GDB will
6132 continue to accept the old forms (-option and +option) as well.
6133 Various single letter abbreviations for options have been explicity
6134 added to the option table so that they won't get overshadowed in the
6135 future by other options that begin with the same letter.
6139 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6140 Many assorted bugs have been handled. Many more remain to be handled.
6141 See the various ChangeLog files (primarily in gdb and bfd) for details.
6144 *** Changes in GDB-4.3:
6146 * New machines supported (host and target)
6148 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6149 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6150 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6152 * Almost SCO Unix support
6154 We had hoped to support:
6155 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6156 (except for core file support), but we discovered very late in the release
6157 that it has problems with process groups that render gdb unusable. Sorry
6158 about that. I encourage people to fix it and post the fixes.
6160 * Preliminary ELF and DWARF support
6162 GDB can read ELF object files on System V Release 4, and can handle
6163 debugging records for C, in DWARF format, in ELF files. This support
6164 is preliminary. If you bring up GDB on another SVR4 system, please
6165 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6170 GDB now uses the latest `readline' library. One user-visible change
6171 is that two tabs will list possible command completions, which previously
6172 required typing M-? (meta-question mark, or ESC ?).
6176 The `stepi' bug that many of you noticed has been squashed.
6177 Many bugs in C++ have been handled. Many more remain to be handled.
6178 See the various ChangeLog files (primarily in gdb and bfd) for details.
6180 * State of the MIPS world (in case you wondered):
6182 GDB can understand the symbol tables emitted by the compilers
6183 supplied by most vendors of MIPS-based machines, including DEC. These
6184 symbol tables are in a format that essentially nobody else uses.
6186 Some versions of gcc come with an assembler post-processor called
6187 mips-tfile. This program is required if you want to do source-level
6188 debugging of gcc-compiled programs. I believe FSF does not ship
6189 mips-tfile with gcc version 1, but it will eventually come with gcc
6192 Debugging of g++ output remains a problem. g++ version 1.xx does not
6193 really support it at all. (If you're lucky, you should be able to get
6194 line numbers and stack traces to work, but no parameters or local
6195 variables.) With some work it should be possible to improve the
6198 When gcc version 2 is released, you will have somewhat better luck.
6199 However, even then you will get confusing results for inheritance and
6202 We will eventually provide full debugging of g++ output on
6203 DECstations. This will probably involve some kind of stabs-in-ecoff
6204 encapulation, but the details have not been worked out yet.
6207 *** Changes in GDB-4.2:
6209 * Improved configuration
6211 Only one copy of `configure' exists now, and it is not self-modifying.
6212 Porting BFD is simpler.
6216 The `step' and `next' commands now only stop at the first instruction
6217 of a source line. This prevents the multiple stops that used to occur
6218 in switch statements, for-loops, etc. `Step' continues to stop if a
6219 function that has debugging information is called within the line.
6223 Lots of small bugs fixed. More remain.
6225 * New host supported (not target)
6227 Intel 386 PC clone running Mach i386-none-mach
6230 *** Changes in GDB-4.1:
6232 * Multiple source language support
6234 GDB now has internal scaffolding to handle several source languages.
6235 It determines the type of each source file from its filename extension,
6236 and will switch expression parsing and number formatting to match the
6237 language of the function in the currently selected stack frame.
6238 You can also specifically set the language to be used, with
6239 `set language c' or `set language modula-2'.
6243 GDB now has preliminary support for the GNU Modula-2 compiler,
6244 currently under development at the State University of New York at
6245 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6246 continue through the fall of 1991 and into 1992.
6248 Other Modula-2 compilers are currently not supported, and attempting to
6249 debug programs compiled with them will likely result in an error as the
6250 symbol table is read. Feel free to work on it, though!
6252 There are hooks in GDB for strict type checking and range checking,
6253 in the `Modula-2 philosophy', but they do not currently work.
6257 GDB can now write to executable and core files (e.g. patch
6258 a variable's value). You must turn this switch on, specify
6259 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6260 by assigning a new value to a variable. Modifications take
6263 * Automatic SunOS shared library reading
6265 When you run your program, GDB automatically determines where its
6266 shared libraries (if any) have been loaded, and reads their symbols.
6267 The `share' command is no longer needed. This also works when
6268 examining core files.
6272 You can specify the number of lines that the `list' command shows.
6275 * New machines supported (host and target)
6277 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6278 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6279 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6281 * New hosts supported (not targets)
6283 IBM RT/PC: romp-ibm-aix or rtpc
6285 * New targets supported (not hosts)
6287 AMD 29000 embedded with COFF a29k-none-coff
6288 AMD 29000 embedded with a.out a29k-none-aout
6289 Ultracomputer remote kernel debug a29k-nyu-kern
6291 * New remote interfaces
6297 *** Changes in GDB-4.0:
6301 Wide output is wrapped at good places to make the output more readable.
6303 Gdb now supports cross-debugging from a host machine of one type to a
6304 target machine of another type. Communication with the target system
6305 is over serial lines. The ``target'' command handles connecting to the
6306 remote system; the ``load'' command will download a program into the
6307 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6308 also supports debugging of realtime processes running under VxWorks,
6309 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6310 stub on the target system.
6312 New CPUs supported include the AMD 29000 and Intel 960.
6314 GDB now reads object files and symbol tables via a ``binary file''
6315 library, which allows a single copy of GDB to debug programs of multiple
6316 object file types such as a.out and coff.
6318 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6319 refcard.dvi and refcard.ps are available to format it).
6322 * Control-Variable user interface simplified
6324 All variables that control the operation of the debugger can be set
6325 by the ``set'' command, and displayed by the ``show'' command.
6327 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6328 ``Show prompt'' produces the response:
6329 Gdb's prompt is new-gdb=>.
6331 What follows are the NEW set commands. The command ``help set'' will
6332 print a complete list of old and new set commands. ``help set FOO''
6333 will give a longer description of the variable FOO. ``show'' will show
6334 all of the variable descriptions and their current settings.
6336 confirm on/off: Enables warning questions for operations that are
6337 hard to recover from, e.g. rerunning the program while
6338 it is already running. Default is ON.
6340 editing on/off: Enables EMACS style command line editing
6341 of input. Previous lines can be recalled with
6342 control-P, the current line can be edited with control-B,
6343 you can search for commands with control-R, etc.
6346 history filename NAME: NAME is where the gdb command history
6347 will be stored. The default is .gdb_history,
6348 or the value of the environment variable
6351 history size N: The size, in commands, of the command history. The
6352 default is 256, or the value of the environment variable
6355 history save on/off: If this value is set to ON, the history file will
6356 be saved after exiting gdb. If set to OFF, the
6357 file will not be saved. The default is OFF.
6359 history expansion on/off: If this value is set to ON, then csh-like
6360 history expansion will be performed on
6361 command line input. The default is OFF.
6363 radix N: Sets the default radix for input and output. It can be set
6364 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6365 in the current radix, so "set radix 10" is always a no-op.
6367 height N: This integer value is the number of lines on a page. Default
6368 is 24, the current `stty rows'' setting, or the ``li#''
6369 setting from the termcap entry matching the environment
6372 width N: This integer value is the number of characters on a line.
6373 Default is 80, the current `stty cols'' setting, or the ``co#''
6374 setting from the termcap entry matching the environment
6377 Note: ``set screensize'' is obsolete. Use ``set height'' and
6378 ``set width'' instead.
6380 print address on/off: Print memory addresses in various command displays,
6381 such as stack traces and structure values. Gdb looks
6382 more ``symbolic'' if you turn this off; it looks more
6383 ``machine level'' with it on. Default is ON.
6385 print array on/off: Prettyprint arrays. New convenient format! Default
6388 print demangle on/off: Print C++ symbols in "source" form if on,
6391 print asm-demangle on/off: Same, for assembler level printouts
6394 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6397 * Support for Epoch Environment.
6399 The epoch environment is a version of Emacs v18 with windowing. One
6400 new command, ``inspect'', is identical to ``print'', except that if you
6401 are running in the epoch environment, the value is printed in its own
6405 * Support for Shared Libraries
6407 GDB can now debug programs and core files that use SunOS shared libraries.
6408 Symbols from a shared library cannot be referenced
6409 before the shared library has been linked with the program (this
6410 happens after you type ``run'' and before the function main() is entered).
6411 At any time after this linking (including when examining core files
6412 from dynamically linked programs), gdb reads the symbols from each
6413 shared library when you type the ``sharedlibrary'' command.
6414 It can be abbreviated ``share''.
6416 sharedlibrary REGEXP: Load shared object library symbols for files
6417 matching a unix regular expression. No argument
6418 indicates to load symbols for all shared libraries.
6420 info sharedlibrary: Status of loaded shared libraries.
6425 A watchpoint stops execution of a program whenever the value of an
6426 expression changes. Checking for this slows down execution
6427 tremendously whenever you are in the scope of the expression, but is
6428 quite useful for catching tough ``bit-spreader'' or pointer misuse
6429 problems. Some machines such as the 386 have hardware for doing this
6430 more quickly, and future versions of gdb will use this hardware.
6432 watch EXP: Set a watchpoint (breakpoint) for an expression.
6434 info watchpoints: Information about your watchpoints.
6436 delete N: Deletes watchpoint number N (same as breakpoints).
6437 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6438 enable N: Re-enables watchpoint number N (same as breakpoints).
6441 * C++ multiple inheritance
6443 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6446 * C++ exception handling
6448 Gdb now supports limited C++ exception handling. Besides the existing
6449 ability to breakpoint on an exception handler, gdb can breakpoint on
6450 the raising of an exception (before the stack is peeled back to the
6453 catch FOO: If there is a FOO exception handler in the dynamic scope,
6454 set a breakpoint to catch exceptions which may be raised there.
6455 Multiple exceptions (``catch foo bar baz'') may be caught.
6457 info catch: Lists all exceptions which may be caught in the
6458 current stack frame.
6461 * Minor command changes
6463 The command ``call func (arg, arg, ...)'' now acts like the print
6464 command, except it does not print or save a value if the function's result
6465 is void. This is similar to dbx usage.
6467 The ``up'' and ``down'' commands now always print the frame they end up
6468 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6469 frames without printing.
6471 * New directory command
6473 'dir' now adds directories to the FRONT of the source search path.
6474 The path starts off empty. Source files that contain debug information
6475 about the directory in which they were compiled can be found even
6476 with an empty path; Sun CC and GCC include this information. If GDB can't
6477 find your source file in the current directory, type "dir .".
6479 * Configuring GDB for compilation
6481 For normal use, type ``./configure host''. See README or gdb.texinfo
6484 GDB now handles cross debugging. If you are remotely debugging between
6485 two different machines, type ``./configure host -target=targ''.
6486 Host is the machine where GDB will run; targ is the machine
6487 where the program that you are debugging will run.
projects / external / binutils.git / blob