1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.11
6 * Intel MPX bound violation handling.
8 Segmentation faults caused by a Intel MPX boundary violation
9 now display the kind of violation (upper or lower), the memory
10 address accessed and the memory bounds, along with the usual
11 signal received and code location.
15 Program received signal SIGSEGV, Segmentation fault
16 Upper bound violation while accessing address 0x7fffffffc3b3
17 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
18 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
23 skip -gfile file-glob-pattern
24 skip -function function
25 skip -rfunction regular-expression
26 A generalized form of the skip command, with new support for
27 glob-style file names and regular expressions for function names.
28 Additionally, a file spec and a function spec may now be combined.
30 *** Changes in GDB 7.11
32 * GDB now supports debugging kernel-based threads on FreeBSD.
34 * Per-inferior thread numbers
36 Thread numbers are now per inferior instead of global. If you're
37 debugging multiple inferiors, GDB displays thread IDs using a
38 qualified INF_NUM.THR_NUM form. For example:
42 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
43 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
44 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
45 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
47 As consequence, thread numbers as visible in the $_thread
48 convenience variable and in Python's InferiorThread.num attribute
49 are no longer unique between inferiors.
51 GDB now maintains a second thread ID per thread, referred to as the
52 global thread ID, which is the new equivalent of thread numbers in
53 previous releases. See also $_gthread below.
55 For backwards compatibility, MI's thread IDs always refer to global
58 * Commands that accept thread IDs now accept the qualified
59 INF_NUM.THR_NUM form as well. For example:
62 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
65 * In commands that accept a list of thread IDs, you can now refer to
66 all threads of an inferior using a star wildcard. GDB accepts
67 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
68 refer to all threads of the current inferior. For example, "info
71 * You can use "info threads -gid" to display the global thread ID of
74 * The new convenience variable $_gthread holds the global number of
77 * The new convenience variable $_inferior holds the number of the
80 * GDB now displays the ID and name of the thread that hit a breakpoint
81 or received a signal, if your program is multi-threaded. For
84 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
85 Thread 1 "main" received signal SIGINT, Interrupt.
87 * Record btrace now supports non-stop mode.
89 * Support for tracepoints on aarch64-linux was added in GDBserver.
91 * The 'record instruction-history' command now indicates speculative execution
92 when using the Intel Processor Trace recording format.
94 * GDB now allows users to specify explicit locations, bypassing
95 the linespec parser. This feature is also available to GDB/MI
98 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
99 GDB now is able to debug both AArch64 applications and ARM applications
102 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
103 including JIT compiling fast tracepoint's conditional expression bytecode
106 * GDB now supports displaced stepping on AArch64 GNU/Linux.
108 * "info threads", "info inferiors", "info display", "info checkpoints"
109 and "maint info program-spaces" now list the corresponding items in
110 ascending ID order, for consistency with all other "info" commands.
112 * In Ada, the overloads selection menu has been enhanced to display the
113 parameter types and the return types for the matching overloaded subprograms.
117 maint set target-non-stop (on|off|auto)
118 maint show target-non-stop
119 Control whether GDB targets always operate in non-stop mode even if
120 "set non-stop" is "off". The default is "auto", meaning non-stop
121 mode is enabled if supported by the target.
123 maint set bfd-sharing
124 maint show bfd-sharing
125 Control the reuse of bfd objects.
129 Control display of debugging info regarding bfd caching.
133 Control display of debugging info regarding FreeBSD threads.
135 set remote multiprocess-extensions-packet
136 show remote multiprocess-extensions-packet
137 Set/show the use of the remote protocol multiprocess extensions.
139 set remote thread-events
140 show remote thread-events
141 Set/show the use of thread create/exit events.
143 set ada print-signatures on|off
144 show ada print-signatures"
145 Control whether parameter types and return types are displayed in overloads
146 selection menus. It is activaled (@code{on}) by default.
150 Controls the maximum size of memory, in bytes, that GDB will
151 allocate for value contents. Prevents incorrect programs from
152 causing GDB to allocate overly large buffers. Default is 64k.
154 * The "disassemble" command accepts a new modifier: /s.
155 It prints mixed source+disassembly like /m with two differences:
156 - disassembled instructions are now printed in program order, and
157 - and source for all relevant files is now printed.
158 The "/m" option is now considered deprecated: its "source-centric"
159 output hasn't proved useful in practice.
161 * The "record instruction-history" command accepts a new modifier: /s.
162 It behaves exactly like /m and prints mixed source+disassembly.
164 * The "set scheduler-locking" command supports a new mode "replay".
165 It behaves like "off" in record mode and like "on" in replay mode.
167 * Support for various ROM monitors has been removed:
169 target dbug dBUG ROM monitor for Motorola ColdFire
170 target picobug Motorola picobug monitor
171 target dink32 DINK32 ROM monitor for PowerPC
172 target m32r Renesas M32R/D ROM monitor
173 target mon2000 mon2000 ROM monitor
174 target ppcbug PPCBUG ROM monitor for PowerPC
176 * Support for reading/writing memory and extracting values on architectures
177 whose memory is addressable in units of any integral multiple of 8 bits.
182 Indicates that an exec system call was executed.
184 exec-events feature in qSupported
185 The qSupported packet allows GDB to request support for exec
186 events using the new 'gdbfeature' exec-event, and the qSupported
187 response can contain the corresponding 'stubfeature'. Set and
188 show commands can be used to display whether these features are enabled.
191 Equivalent to interrupting with the ^C character, but works in
194 thread created stop reason (T05 create:...)
195 Indicates that the thread was just created and is stopped at entry.
197 thread exit stop reply (w exitcode;tid)
198 Indicates that the thread has terminated.
201 Enables/disables thread create and exit event reporting. For
202 example, this is used in non-stop mode when GDB stops a set of
203 threads and synchronously waits for the their corresponding stop
204 replies. Without exit events, if one of the threads exits, GDB
205 would hang forever not knowing that it should no longer expect a
206 stop for that same thread.
210 Indicates that there are no resumed threads left in the target (all
211 threads are stopped). The remote stub reports support for this stop
212 reply to GDB's qSupported query.
214 QCatchSyscalls:1 [;SYSNO]...
216 Enable ("QCatchSyscalls:1") or disable ("QCatchSyscalls:0")
217 catching syscalls from the inferior process.
219 syscall_entry stop reason
220 Indicates that a syscall was just called.
222 syscall_return stop reason
223 Indicates that a syscall just returned.
225 QCatchSyscalls:1 in qSupported
226 The qSupported packet may now include QCatchSyscalls:1 in the reply
227 to indicate support for catching syscalls.
229 * Extended-remote exec events
231 ** GDB now has support for exec events on extended-remote Linux targets.
232 For such targets with Linux kernels 2.5.46 and later, this enables
233 follow-exec-mode and exec catchpoints.
235 set remote exec-event-feature-packet
236 show remote exec-event-feature-packet
237 Set/show the use of the remote exec event feature.
239 * Thread names in remote protocol
241 The reply to qXfer:threads:read may now include a name attribute for each
244 * Target remote mode fork and exec events
246 ** GDB now has support for fork and exec events on target remote mode
247 Linux targets. For such targets with Linux kernels 2.5.46 and later,
248 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
249 fork and exec catchpoints.
251 * Remote syscall events
253 ** GDB now has support for catch syscall on remote Linux targets,
254 currently enabled on x86/x86_64 architectures.
256 set remote catch-syscall-packet
257 show remote catch-syscall-packet
258 Set/show the use of the remote catch syscall feature.
262 ** The -var-set-format command now accepts the zero-hexadecimal
263 format. It outputs data in hexadecimal format with zero-padding on the
268 ** gdb.InferiorThread objects have a new attribute "global_num",
269 which refers to the thread's global thread ID. The existing
270 "num" attribute now refers to the thread's per-inferior number.
271 See "Per-inferior thread numbers" above.
272 ** gdb.InferiorThread objects have a new attribute "inferior", which
273 is the Inferior object the thread belongs to.
275 *** Changes in GDB 7.10
277 * Support for process record-replay and reverse debugging on aarch64*-linux*
278 targets has been added. GDB now supports recording of A64 instruction set
279 including advance SIMD instructions.
281 * Support for Sun's version of the "stabs" debug file format has been removed.
283 * GDB now honors the content of the file /proc/PID/coredump_filter
284 (PID is the process ID) on GNU/Linux systems. This file can be used
285 to specify the types of memory mappings that will be included in a
286 corefile. For more information, please refer to the manual page of
287 "core(5)". GDB also has a new command: "set use-coredump-filter
288 on|off". It allows to set whether GDB will read the content of the
289 /proc/PID/coredump_filter file when generating a corefile.
291 * The "info os" command on GNU/Linux can now display information on
293 "info os cpus" Listing of all cpus/cores on the system
295 * GDB has two new commands: "set serial parity odd|even|none" and
296 "show serial parity". These allows to set or show parity for the
299 * The "info source" command now displays the producer string if it was
300 present in the debug info. This typically includes the compiler version
301 and may include things like its command line arguments.
303 * The "info dll", an alias of the "info sharedlibrary" command,
304 is now available on all platforms.
306 * Directory names supplied to the "set sysroot" commands may be
307 prefixed with "target:" to tell GDB to access shared libraries from
308 the target system, be it local or remote. This replaces the prefix
309 "remote:". The default sysroot has been changed from "" to
310 "target:". "remote:" is automatically converted to "target:" for
311 backward compatibility.
313 * The system root specified by "set sysroot" will be prepended to the
314 filename of the main executable (if reported to GDB as absolute by
315 the operating system) when starting processes remotely, and when
316 attaching to already-running local or remote processes.
318 * GDB now supports automatic location and retrieval of executable
319 files from remote targets. Remote debugging can now be initiated
320 using only a "target remote" or "target extended-remote" command
321 (no "set sysroot" or "file" commands are required). See "New remote
324 * The "dump" command now supports verilog hex format.
326 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
328 * On GNU/Linux, GDB and gdbserver are now able to access executable
329 and shared library files without a "set sysroot" command when
330 attaching to processes running in different mount namespaces from
331 the debugger. This makes it possible to attach to processes in
332 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
333 See "New remote packets" below.
335 * The "tui reg" command now provides completion for all of the
336 available register groups, including target specific groups.
338 * The HISTSIZE environment variable is no longer read when determining
339 the size of GDB's command history. GDB now instead reads the dedicated
340 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
341 disables truncation of command history. Non-numeric values of GDBHISTSIZE
346 ** Memory ports can now be unbuffered.
350 ** gdb.Objfile objects have a new attribute "username",
351 which is the name of the objfile as specified by the user,
352 without, for example, resolving symlinks.
353 ** You can now write frame unwinders in Python.
354 ** gdb.Type objects have a new method "optimized_out",
355 returning optimized out gdb.Value instance of this type.
356 ** gdb.Value objects have new methods "reference_value" and
357 "const_value" which return a reference to the value and a
358 "const" version of the value respectively.
362 maint print symbol-cache
363 Print the contents of the symbol cache.
365 maint print symbol-cache-statistics
366 Print statistics of symbol cache usage.
368 maint flush-symbol-cache
369 Flush the contents of the symbol cache.
373 Start branch trace recording using Branch Trace Store (BTS) format.
376 Evaluate expression by using the compiler and print result.
380 Explicit commands for enabling and disabling tui mode.
383 set mpx bound on i386 and amd64
384 Support for bound table investigation on Intel MPX enabled applications.
388 Start branch trace recording using Intel Processor Trace format.
391 Print information about branch tracing internals.
393 maint btrace packet-history
394 Print the raw branch tracing data.
396 maint btrace clear-packet-history
397 Discard the stored raw branch tracing data.
400 Discard all branch tracing data. It will be fetched and processed
401 anew by the next "record" command.
406 Renamed from "set debug dwarf2-die".
408 Renamed from "show debug dwarf2-die".
411 Renamed from "set debug dwarf2-read".
412 show debug dwarf-read
413 Renamed from "show debug dwarf2-read".
415 maint set dwarf always-disassemble
416 Renamed from "maint set dwarf2 always-disassemble".
417 maint show dwarf always-disassemble
418 Renamed from "maint show dwarf2 always-disassemble".
420 maint set dwarf max-cache-age
421 Renamed from "maint set dwarf2 max-cache-age".
422 maint show dwarf max-cache-age
423 Renamed from "maint show dwarf2 max-cache-age".
426 show debug dwarf-line
427 Control display of debugging info regarding DWARF line processing.
431 Set the maximum number of candidates to be considered during
432 completion. The default value is 200. This limit allows GDB
433 to avoid generating large completion lists, the computation of
434 which can cause the debugger to become temporarily unresponsive.
436 set history remove-duplicates
437 show history remove-duplicates
438 Control the removal of duplicate history entries.
440 maint set symbol-cache-size
441 maint show symbol-cache-size
442 Control the size of the symbol cache.
444 set|show record btrace bts buffer-size
445 Set and show the size of the ring buffer used for branch tracing in
447 The obtained size may differ from the requested size. Use "info
448 record" to see the obtained buffer size.
450 set debug linux-namespaces
451 show debug linux-namespaces
452 Control display of debugging info regarding Linux namespaces.
454 set|show record btrace pt buffer-size
455 Set and show the size of the ring buffer used for branch tracing in
456 Intel Processor Trace format.
457 The obtained size may differ from the requested size. Use "info
458 record" to see the obtained buffer size.
460 maint set|show btrace pt skip-pad
461 Set and show whether PAD packets are skipped when computing the
464 * The command 'thread apply all' can now support new option '-ascending'
465 to call its specified command for all threads in ascending order.
467 * Python/Guile scripting
469 ** GDB now supports auto-loading of Python/Guile scripts contained in the
470 special section named `.debug_gdb_scripts'.
474 qXfer:btrace-conf:read
475 Return the branch trace configuration for the current thread.
477 Qbtrace-conf:bts:size
478 Set the requested ring buffer size for branch tracing in BTS format.
481 Enable Intel Procesor Trace-based branch tracing for the current
482 process. The remote stub reports support for this packet to GDB's
486 Set the requested ring buffer size for branch tracing in Intel Processor
490 Indicates a memory breakpoint instruction was executed, irrespective
491 of whether it was GDB that planted the breakpoint or the breakpoint
492 is hardcoded in the program. This is required for correct non-stop
496 Indicates the target stopped for a hardware breakpoint. This is
497 required for correct non-stop mode operation.
500 Return information about files on the remote system.
503 Return the full absolute name of the file that was executed to
504 create a process running on the remote system.
507 Select the filesystem on which vFile: operations with filename
508 arguments will operate. This is required for GDB to be able to
509 access files on remote targets where the remote stub does not
510 share a common filesystem with the inferior(s).
513 Indicates that a fork system call was executed.
516 Indicates that a vfork system call was executed.
518 vforkdone stop reason
519 Indicates that a vfork child of the specified process has executed
520 an exec or exit, allowing the vfork parent to resume execution.
522 fork-events and vfork-events features in qSupported
523 The qSupported packet allows GDB to request support for fork and
524 vfork events using new 'gdbfeatures' fork-events and vfork-events,
525 and the qSupported response can contain the corresponding
526 'stubfeatures'. Set and show commands can be used to display
527 whether these features are enabled.
529 * Extended-remote fork events
531 ** GDB now has support for fork events on extended-remote Linux
532 targets. For targets with Linux kernels 2.5.60 and later, this
533 enables follow-fork-mode and detach-on-fork for both fork and
534 vfork, as well as fork and vfork catchpoints.
536 * The info record command now shows the recording format and the
537 branch tracing configuration for the current thread when using
538 the btrace record target.
539 For the BTS format, it shows the ring buffer size.
541 * GDB now has support for DTrace USDT (Userland Static Defined
542 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
544 * GDB now supports access to vector registers on S/390 GNU/Linux
547 * Removed command line options
549 -xdb HP-UX XDB compatibility mode.
551 * Removed targets and native configurations
553 HP/PA running HP-UX hppa*-*-hpux*
554 Itanium running HP-UX ia64-*-hpux*
556 * New configure options
559 This configure option allows the user to build GDB with support for
560 Intel Processor Trace (default: auto). This requires libipt.
562 --with-libipt-prefix=PATH
563 Specify the path to the version of libipt that GDB should use.
564 $PATH/include should contain the intel-pt.h header and
565 $PATH/lib should contain the libipt.so library.
567 *** Changes in GDB 7.9.1
571 ** Xmethods can now specify a result type.
573 *** Changes in GDB 7.9
575 * GDB now supports hardware watchpoints on x86 GNU Hurd.
579 ** You can now access frame registers from Python scripts.
580 ** New attribute 'producer' for gdb.Symtab objects.
581 ** gdb.Objfile objects have a new attribute "progspace",
582 which is the gdb.Progspace object of the containing program space.
583 ** gdb.Objfile objects have a new attribute "owner".
584 ** gdb.Objfile objects have a new attribute "build_id",
585 which is the build ID generated when the file was built.
586 ** gdb.Objfile objects have a new method "add_separate_debug_file".
587 ** A new event "gdb.clear_objfiles" has been added, triggered when
588 selecting a new file to debug.
589 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
590 ** New function gdb.lookup_objfile.
592 New events which are triggered when GDB modifies the state of the
595 ** gdb.events.inferior_call_pre: Function call is about to be made.
596 ** gdb.events.inferior_call_post: Function call has just been made.
597 ** gdb.events.memory_changed: A memory location has been altered.
598 ** gdb.events.register_changed: A register has been altered.
600 * New Python-based convenience functions:
602 ** $_caller_is(name [, number_of_frames])
603 ** $_caller_matches(regexp [, number_of_frames])
604 ** $_any_caller_is(name [, number_of_frames])
605 ** $_any_caller_matches(regexp [, number_of_frames])
607 * GDB now supports the compilation and injection of source code into
608 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
609 to compile the source code to object code, and if successful, inject
610 and execute that code within the current context of the inferior.
611 Currently the C language is supported. The commands used to
612 interface with this new feature are:
614 compile code [-raw|-r] [--] [source code]
615 compile file [-raw|-r] filename
619 demangle [-l language] [--] name
620 Demangle "name" in the specified language, or the current language
621 if elided. This command is renamed from the "maint demangle" command.
622 The latter is kept as a no-op to avoid "maint demangle" being interpreted
623 as "maint demangler-warning".
625 queue-signal signal-name-or-number
626 Queue a signal to be delivered to the thread when it is resumed.
628 add-auto-load-scripts-directory directory
629 Add entries to the list of directories from which to load auto-loaded
632 maint print user-registers
633 List all currently available "user" registers.
635 compile code [-r|-raw] [--] [source code]
636 Compile, inject, and execute in the inferior the executable object
637 code produced by compiling the provided source code.
639 compile file [-r|-raw] filename
640 Compile and inject into the inferior the executable object code
641 produced by compiling the source code stored in the filename
644 * On resume, GDB now always passes the signal the program had stopped
645 for to the thread the signal was sent to, even if the user changed
646 threads before resuming. Previously GDB would often (but not
647 always) deliver the signal to the thread that happens to be current
650 * Conversely, the "signal" command now consistently delivers the
651 requested signal to the current thread. GDB now asks for
652 confirmation if the program had stopped for a signal and the user
653 switched threads meanwhile.
655 * "breakpoint always-inserted" modes "off" and "auto" merged.
657 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
658 won't remove breakpoints from the target until all threads stop,
659 even in non-stop mode. The "auto" mode has been removed, and "off"
660 is now the default mode.
664 set debug symbol-lookup
665 show debug symbol-lookup
666 Control display of debugging info regarding symbol lookup.
670 ** The -list-thread-groups command outputs an exit-code field for
671 inferiors that have exited.
675 MIPS SDE mips*-sde*-elf*
679 Support for these obsolete configurations has been removed.
681 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
682 SGI Irix-5.x mips-*-irix5*
683 SGI Irix-6.x mips-*-irix6*
684 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
685 VAX running Ultrix vax-*-ultrix*
687 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
688 and "assf"), have been removed. Use the "sharedlibrary" command, or
689 its alias "share", instead.
691 *** Changes in GDB 7.8
693 * New command line options
696 This is an alias for the --data-directory option.
698 * GDB supports printing and modifying of variable length automatic arrays
699 as specified in ISO C99.
701 * The ARM simulator now supports instruction level tracing
702 with or without disassembly.
706 GDB now has support for scripting using Guile. Whether this is
707 available is determined at configure time.
708 Guile version 2.0 or greater is required.
709 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
711 * New commands (for set/show, see "New options" below)
715 Invoke CODE by passing it to the Guile interpreter.
719 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
721 info auto-load guile-scripts [regexp]
722 Print the list of automatically loaded Guile scripts.
724 * The source command is now capable of sourcing Guile scripts.
725 This feature is dependent on the debugger being built with Guile support.
729 set print symbol-loading (off|brief|full)
730 show print symbol-loading
731 Control whether to print informational messages when loading symbol
732 information for a file. The default is "full", but when debugging
733 programs with large numbers of shared libraries the amount of output
736 set guile print-stack (none|message|full)
737 show guile print-stack
738 Show a stack trace when an error is encountered in a Guile script.
740 set auto-load guile-scripts (on|off)
741 show auto-load guile-scripts
742 Control auto-loading of Guile script files.
744 maint ada set ignore-descriptive-types (on|off)
745 maint ada show ignore-descriptive-types
746 Control whether the debugger should ignore descriptive types in Ada
747 programs. The default is not to ignore the descriptive types. See
748 the user manual for more details on descriptive types and the intended
749 usage of this option.
751 set auto-connect-native-target
753 Control whether GDB is allowed to automatically connect to the
754 native target for the run, attach, etc. commands when not connected
755 to any target yet. See also "target native" below.
757 set record btrace replay-memory-access (read-only|read-write)
758 show record btrace replay-memory-access
759 Control what memory accesses are allowed during replay.
761 maint set target-async (on|off)
762 maint show target-async
763 This controls whether GDB targets operate in synchronous or
764 asynchronous mode. Normally the default is asynchronous, if it is
765 available; but this can be changed to more easily debug problems
766 occurring only in synchronous mode.
768 set mi-async (on|off)
770 Control whether MI asynchronous mode is preferred. This supersedes
771 "set target-async" of previous GDB versions.
773 * "set target-async" is deprecated as a CLI option and is now an alias
774 for "set mi-async" (only puts MI into async mode).
776 * Background execution commands (e.g., "c&", "s&", etc.) are now
777 possible ``out of the box'' if the target supports them. Previously
778 the user would need to explicitly enable the possibility with the
779 "set target-async on" command.
781 * New features in the GDB remote stub, GDBserver
783 ** New option --debug-format=option1[,option2,...] allows one to add
784 additional text to each output. At present only timestamps
785 are supported: --debug-format=timestamps.
786 Timestamps can also be turned on with the
787 "monitor set debug-format timestamps" command from GDB.
789 * The 'record instruction-history' command now starts counting instructions
790 at one. This also affects the instruction ranges reported by the
791 'record function-call-history' command when given the /i modifier.
793 * The command 'record function-call-history' supports a new modifier '/c' to
794 indent the function names based on their call stack depth.
795 The fields for the '/i' and '/l' modifier have been reordered.
796 The source line range is now prefixed with 'at'.
797 The instruction range is now prefixed with 'inst'.
798 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
799 "record instruction-history" and "list" commands.
801 * The ranges given as arguments to the 'record function-call-history' and
802 'record instruction-history' commands are now inclusive.
804 * The btrace record target now supports the 'record goto' command.
805 For locations inside the execution trace, the back trace is computed
806 based on the information stored in the execution trace.
808 * The btrace record target supports limited reverse execution and replay.
809 The target does not record data and therefore does not allow reading
812 * The "catch syscall" command now works on s390*-linux* targets.
814 * The "compare-sections" command is no longer specific to target
815 remote. It now works with all targets.
817 * All native targets are now consistently called "native".
818 Consequently, the "target child", "target GNU", "target djgpp",
819 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
820 commands have been replaced with "target native". The QNX/NTO port
821 leaves the "procfs" target in place and adds a "native" target for
822 consistency with other ports. The impact on users should be minimal
823 as these commands previously either throwed an error, or were
824 no-ops. The target's name is visible in the output of the following
825 commands: "help target", "info target", "info files", "maint print
828 * The "target native" command now connects to the native target. This
829 can be used to launch native programs even when "set
830 auto-connect-native-target" is set to off.
832 * GDB now supports access to Intel MPX registers on GNU/Linux.
834 * Support for Intel AVX-512 registers on GNU/Linux.
835 Support displaying and modifying Intel AVX-512 registers
836 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
840 qXfer:btrace:read's annex
841 The qXfer:btrace:read packet supports a new annex 'delta' to read
842 branch trace incrementally.
846 ** Valid Python operations on gdb.Value objects representing
847 structs/classes invoke the corresponding overloaded operators if
849 ** New `Xmethods' feature in the Python API. Xmethods are
850 additional methods or replacements for existing methods of a C++
851 class. This feature is useful for those cases where a method
852 defined in C++ source code could be inlined or optimized out by
853 the compiler, making it unavailable to GDB.
856 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
858 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
859 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
860 its alias "share", instead.
862 * The commands "set remotebaud" and "show remotebaud" are no longer
863 supported. Use "set serial baud" and "show serial baud" (respectively)
868 ** A new option "-gdb-set mi-async" replaces "-gdb-set
869 target-async". The latter is left as a deprecated alias of the
870 former for backward compatibility. If the target supports it,
871 CLI background execution commands are now always possible by
872 default, independently of whether the frontend stated a
873 preference for asynchronous execution with "-gdb-set mi-async".
874 Previously "-gdb-set target-async off" affected both MI execution
875 commands and CLI execution commands.
877 *** Changes in GDB 7.7
879 * Improved support for process record-replay and reverse debugging on
880 arm*-linux* targets. Support for thumb32 and syscall instruction
881 recording has been added.
883 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
885 * GDB now supports Fission DWP file format version 2.
886 http://gcc.gnu.org/wiki/DebugFission
888 * New convenience function "$_isvoid", to check whether an expression
889 is void. A void expression is an expression where the type of the
890 result is "void". For example, some convenience variables may be
891 "void" when evaluated (e.g., "$_exitcode" before the execution of
892 the program being debugged; or an undefined convenience variable).
893 Another example, when calling a function whose return type is
896 * The "maintenance print objfiles" command now takes an optional regexp.
898 * The "catch syscall" command now works on arm*-linux* targets.
900 * GDB now consistently shows "<not saved>" when printing values of
901 registers the debug info indicates have not been saved in the frame
902 and there's nowhere to retrieve them from
903 (callee-saved/call-clobbered registers):
908 (gdb) info registers rax
911 Before, the former would print "<optimized out>", and the latter
912 "*value not available*".
914 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
919 ** Frame filters and frame decorators have been added.
920 ** Temporary breakpoints are now supported.
921 ** Line tables representation has been added.
922 ** New attribute 'parent_type' for gdb.Field objects.
923 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
924 ** New attribute 'name' for gdb.Type objects.
928 Nios II ELF nios2*-*-elf
929 Nios II GNU/Linux nios2*-*-linux
930 Texas Instruments MSP430 msp430*-*-elf
932 * Removed native configurations
934 Support for these a.out NetBSD and OpenBSD obsolete configurations has
935 been removed. ELF variants of these configurations are kept supported.
937 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
938 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
939 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
940 i[34567]86-*-openbsd3.[0-3]
941 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
942 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
943 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
947 Like "catch throw", but catches a re-thrown exception.
949 Renamed from old "maint check-symtabs".
951 Perform consistency checks on symtabs.
953 Expand symtabs matching an optional regexp.
956 Display the details of GDB configure-time options.
958 maint set|show per-command
959 maint set|show per-command space
960 maint set|show per-command time
961 maint set|show per-command symtab
962 Enable display of per-command gdb resource usage.
964 remove-symbol-file FILENAME
965 remove-symbol-file -a ADDRESS
966 Remove a symbol file added via add-symbol-file. The file to remove
967 can be identified by its filename or by an address that lies within
968 the boundaries of this symbol file in memory.
971 info exceptions REGEXP
972 Display the list of Ada exceptions defined in the program being
973 debugged. If provided, only the exceptions whose names match REGEXP
978 set debug symfile off|on
980 Control display of debugging info regarding reading symbol files and
981 symbol tables within those files
983 set print raw frame-arguments
984 show print raw frame-arguments
985 Set/show whether to print frame arguments in raw mode,
986 disregarding any defined pretty-printers.
988 set remote trace-status-packet
989 show remote trace-status-packet
990 Set/show the use of remote protocol qTStatus packet.
994 Control display of debugging messages related to Nios II targets.
998 Control whether target-assisted range stepping is enabled.
1000 set startup-with-shell
1001 show startup-with-shell
1002 Specifies whether Unix child processes are started via a shell or
1007 Use the target memory cache for accesses to the code segment. This
1008 improves performance of remote debugging (particularly disassembly).
1010 * You can now use a literal value 'unlimited' for options that
1011 interpret 0 or -1 as meaning "unlimited". E.g., "set
1012 trace-buffer-size unlimited" is now an alias for "set
1013 trace-buffer-size -1" and "set height unlimited" is now an alias for
1016 * The "set debug symtab-create" debugging option of GDB has been changed to
1017 accept a verbosity level. 0 means "off", 1 provides basic debugging
1018 output, and values of 2 or greater provides more verbose output.
1020 * New command-line options
1022 Display the details of GDB configure-time options.
1024 * The command 'tsave' can now support new option '-ctf' to save trace
1025 buffer in Common Trace Format.
1027 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1030 * GDB now implements the the C++ 'typeid' operator.
1032 * The new convenience variable $_exception holds the exception being
1033 thrown or caught at an exception-related catchpoint.
1035 * The exception-related catchpoints, like "catch throw", now accept a
1036 regular expression which can be used to filter exceptions by type.
1038 * The new convenience variable $_exitsignal is automatically set to
1039 the terminating signal number when the program being debugged dies
1040 due to an uncaught signal.
1044 ** All MI commands now accept an optional "--language" option.
1045 Support for this feature can be verified by using the "-list-features"
1046 command, which should contain "language-option".
1048 ** The new command -info-gdb-mi-command allows the user to determine
1049 whether a GDB/MI command is supported or not.
1051 ** The "^error" result record returned when trying to execute an undefined
1052 GDB/MI command now provides a variable named "code" whose content is the
1053 "undefined-command" error code. Support for this feature can be verified
1054 by using the "-list-features" command, which should contain
1055 "undefined-command-error-code".
1057 ** The -trace-save MI command can optionally save trace buffer in Common
1060 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1062 ** The command -data-list-register-values now accepts an optional
1063 "--skip-unavailable" option. When used, only the available registers
1066 ** The new command -trace-frame-collected dumps collected variables,
1067 computed expressions, tvars, memory and registers in a traceframe.
1069 ** The commands -stack-list-locals, -stack-list-arguments and
1070 -stack-list-variables now accept an option "--skip-unavailable".
1071 When used, only the available locals or arguments are displayed.
1073 ** The -exec-run command now accepts an optional "--start" option.
1074 When used, the command follows the same semantics as the "start"
1075 command, stopping the program's execution at the start of its
1076 main subprogram. Support for this feature can be verified using
1077 the "-list-features" command, which should contain
1078 "exec-run-start-option".
1080 ** The new commands -catch-assert and -catch-exceptions insert
1081 catchpoints stopping the program when Ada exceptions are raised.
1083 ** The new command -info-ada-exceptions provides the equivalent of
1084 the new "info exceptions" command.
1086 * New system-wide configuration scripts
1087 A GDB installation now provides scripts suitable for use as system-wide
1088 configuration scripts for the following systems:
1092 * GDB now supports target-assigned range stepping with remote targets.
1093 This improves the performance of stepping source lines by reducing
1094 the number of control packets from/to GDB. See "New remote packets"
1097 * GDB now understands the element 'tvar' in the XML traceframe info.
1098 It has the id of the collected trace state variables.
1100 * On S/390 targets that provide the transactional-execution feature,
1101 the program interruption transaction diagnostic block (TDB) is now
1102 represented as a number of additional "registers" in GDB.
1104 * New remote packets
1108 The vCont packet supports a new 'r' action, that tells the remote
1109 stub to step through an address range itself, without GDB
1110 involvemement at each single-step.
1112 qXfer:libraries-svr4:read's annex
1113 The previously unused annex of the qXfer:libraries-svr4:read packet
1114 is now used to support passing an argument list. The remote stub
1115 reports support for this argument list to GDB's qSupported query.
1116 The defined arguments are "start" and "prev", used to reduce work
1117 necessary for library list updating, resulting in significant
1120 * New features in the GDB remote stub, GDBserver
1122 ** GDBserver now supports target-assisted range stepping. Currently
1123 enabled on x86/x86_64 GNU/Linux targets.
1125 ** GDBserver now adds element 'tvar' in the XML in the reply to
1126 'qXfer:traceframe-info:read'. It has the id of the collected
1127 trace state variables.
1129 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1132 * New 'z' formatter for printing and examining memory, this displays the
1133 value as hexadecimal zero padded on the left to the size of the type.
1135 * GDB can now use Windows x64 unwinding data.
1137 * The "set remotebaud" command has been replaced by "set serial baud".
1138 Similarly, "show remotebaud" has been replaced by "show serial baud".
1139 The "set remotebaud" and "show remotebaud" commands are still available
1140 to provide backward compatibility with older versions of GDB.
1142 *** Changes in GDB 7.6
1144 * Target record has been renamed to record-full.
1145 Record/replay is now enabled with the "record full" command.
1146 This also affects settings that are associated with full record/replay
1147 that have been moved from "set/show record" to "set/show record full":
1149 set|show record full insn-number-max
1150 set|show record full stop-at-limit
1151 set|show record full memory-query
1153 * A new record target "record-btrace" has been added. The new target
1154 uses hardware support to record the control-flow of a process. It
1155 does not support replaying the execution, but it implements the
1156 below new commands for investigating the recorded execution log.
1157 This new recording method can be enabled using:
1161 The "record-btrace" target is only available on Intel Atom processors
1162 and requires a Linux kernel 2.6.32 or later.
1164 * Two new commands have been added for record/replay to give information
1165 about the recorded execution without having to replay the execution.
1166 The commands are only supported by "record btrace".
1168 record instruction-history prints the execution history at
1169 instruction granularity
1171 record function-call-history prints the execution history at
1172 function granularity
1174 * New native configurations
1176 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1177 FreeBSD/powerpc powerpc*-*-freebsd
1178 x86_64/Cygwin x86_64-*-cygwin*
1179 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1183 ARM AArch64 aarch64*-*-elf
1184 ARM AArch64 GNU/Linux aarch64*-*-linux
1185 Lynx 178 PowerPC powerpc-*-lynx*178
1186 x86_64/Cygwin x86_64-*-cygwin*
1187 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1189 * If the configured location of system.gdbinit file (as given by the
1190 --with-system-gdbinit option at configure time) is in the
1191 data-directory (as specified by --with-gdb-datadir at configure
1192 time) or in one of its subdirectories, then GDB will look for the
1193 system-wide init file in the directory specified by the
1194 --data-directory command-line option.
1196 * New command line options:
1198 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1199 other initialization files, unlike -nx which disables all of them.
1201 * Removed command line options
1203 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1206 * The 'ptype' and 'whatis' commands now accept an argument to control
1209 * 'info proc' now works on some core files.
1213 ** Vectors can be created with gdb.Type.vector.
1215 ** Python's atexit.register now works in GDB.
1217 ** Types can be pretty-printed via a Python API.
1219 ** Python 3 is now supported (in addition to Python 2.4 or later)
1221 ** New class gdb.Architecture exposes GDB's internal representation
1222 of architecture in the Python API.
1224 ** New method Frame.architecture returns the gdb.Architecture object
1225 corresponding to the frame's architecture.
1227 * New Python-based convenience functions:
1229 ** $_memeq(buf1, buf2, length)
1230 ** $_streq(str1, str2)
1232 ** $_regex(str, regex)
1234 * The 'cd' command now defaults to using '~' (the home directory) if not
1237 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1238 default for GCC since November 2000.
1240 * The command 'forward-search' can now be abbreviated as 'fo'.
1242 * The command 'info tracepoints' can now display 'installed on target'
1243 or 'not installed on target' for each non-pending location of tracepoint.
1245 * New configure options
1247 --enable-libmcheck/--disable-libmcheck
1248 By default, development versions are built with -lmcheck on hosts
1249 that support it, in order to help track memory corruption issues.
1250 Release versions, on the other hand, are built without -lmcheck
1251 by default. The --enable-libmcheck/--disable-libmcheck configure
1252 options allow the user to override that default.
1253 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1254 This configure option allows the user to build GDB with
1255 libbabeltrace using which GDB can read Common Trace Format data.
1257 * New commands (for set/show, see "New options" below)
1260 Catch signals. This is similar to "handle", but allows commands and
1261 conditions to be attached.
1264 List the BFDs known to GDB.
1266 python-interactive [command]
1268 Start a Python interactive prompt, or evaluate the optional command
1269 and print the result of expressions.
1272 "py" is a new alias for "python".
1274 enable type-printer [name]...
1275 disable type-printer [name]...
1276 Enable or disable type printers.
1280 ** For the Renesas Super-H architecture, the "regs" command has been removed
1281 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1286 set print type methods (on|off)
1287 show print type methods
1288 Control whether method declarations are displayed by "ptype".
1289 The default is to show them.
1291 set print type typedefs (on|off)
1292 show print type typedefs
1293 Control whether typedef definitions are displayed by "ptype".
1294 The default is to show them.
1296 set filename-display basename|relative|absolute
1297 show filename-display
1298 Control the way in which filenames is displayed.
1299 The default is "relative", which preserves previous behavior.
1301 set trace-buffer-size
1302 show trace-buffer-size
1303 Request target to change the size of trace buffer.
1305 set remote trace-buffer-size-packet auto|on|off
1306 show remote trace-buffer-size-packet
1307 Control the use of the remote protocol `QTBuffer:size' packet.
1311 Control display of debugging messages related to ARM AArch64.
1314 set debug coff-pe-read
1315 show debug coff-pe-read
1316 Control display of debugging messages related to reading of COFF/PE
1321 Control display of debugging messages related to Mach-O symbols
1324 set debug notification
1325 show debug notification
1326 Control display of debugging info for async remote notification.
1330 ** Command parameter changes are now notified using new async record
1331 "=cmd-param-changed".
1332 ** Trace frame changes caused by command "tfind" are now notified using
1333 new async record "=traceframe-changed".
1334 ** The creation, deletion and modification of trace state variables
1335 are now notified using new async records "=tsv-created",
1336 "=tsv-deleted" and "=tsv-modified".
1337 ** The start and stop of process record are now notified using new
1338 async record "=record-started" and "=record-stopped".
1339 ** Memory changes are now notified using new async record
1341 ** The data-disassemble command response will include a "fullname" field
1342 containing the absolute file name when source has been requested.
1343 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1344 command, to allow pattern filling of memory areas.
1345 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1346 library load/unload events.
1347 ** The response to breakpoint commands and breakpoint async records
1348 includes an "installed" field containing a boolean state about each
1349 non-pending tracepoint location is whether installed on target or not.
1350 ** Output of the "-trace-status" command includes a "trace-file" field
1351 containing the name of the trace file being examined. This field is
1352 optional, and only present when examining a trace file.
1353 ** The "fullname" field is now always present along with the "file" field,
1354 even if the file cannot be found by GDB.
1356 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1357 You must have the LZMA library available when configuring GDB for this
1358 feature to be enabled. For more information, see:
1359 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1361 * New remote packets
1364 Set the size of trace buffer. The remote stub reports support for this
1365 packet to gdb's qSupported query.
1368 Enable Branch Trace Store (BTS)-based branch tracing for the current
1369 thread. The remote stub reports support for this packet to gdb's
1373 Disable branch tracing for the current thread. The remote stub reports
1374 support for this packet to gdb's qSupported query.
1377 Read the traced branches for the current thread. The remote stub
1378 reports support for this packet to gdb's qSupported query.
1380 *** Changes in GDB 7.5
1382 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1383 for more x32 ABI info.
1385 * GDB now supports access to MIPS DSP registers on Linux targets.
1387 * GDB now supports debugging microMIPS binaries.
1389 * The "info os" command on GNU/Linux can now display information on
1390 several new classes of objects managed by the operating system:
1391 "info os procgroups" lists process groups
1392 "info os files" lists file descriptors
1393 "info os sockets" lists internet-domain sockets
1394 "info os shm" lists shared-memory regions
1395 "info os semaphores" lists semaphores
1396 "info os msg" lists message queues
1397 "info os modules" lists loaded kernel modules
1399 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1400 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1401 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1402 options and inspect the probe arguments using the new $_probe_arg family
1403 of convenience variables. You can obtain more information about SystemTap
1404 in <http://sourceware.org/systemtap/>.
1406 * GDB now supports reversible debugging on ARM, it allows you to
1407 debug basic ARM and THUMB instructions, and provides
1408 record/replay support.
1410 * The option "symbol-reloading" has been deleted as it is no longer used.
1414 ** GDB commands implemented in Python can now be put in command class
1417 ** The "maint set python print-stack on|off" is now deleted.
1419 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1420 apply "flag enum"-style pretty-printing to any enum.
1422 ** gdb.lookup_symbol can now work when there is no current frame.
1424 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1425 the source at which the symbol was defined.
1427 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1428 method 'value'. The former indicates whether the symbol needs a
1429 frame in order to compute its value, and the latter computes the
1432 ** A new method 'referenced_value' on gdb.Value objects which can
1433 dereference pointer as well as C++ reference values.
1435 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1436 which return the global and static blocks (as gdb.Block objects),
1437 of the underlying symbol table, respectively.
1439 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1440 object associated with a PC value.
1442 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1443 of the address range occupied by code for the current source line.
1445 * Go language support.
1446 GDB now supports debugging programs written in the Go programming
1449 * GDBserver now supports stdio connections.
1450 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1452 * The binary "gdbtui" can no longer be built or installed.
1453 Use "gdb -tui" instead.
1455 * GDB will now print "flag" enums specially. A flag enum is one where
1456 all the enumerator values have no bits in common when pairwise
1457 "and"ed. When printing a value whose type is a flag enum, GDB will
1458 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1459 (gdb) print (enum E) 3
1462 * The filename part of a linespec will now match trailing components
1463 of a source file name. For example, "break gcc/expr.c:1000" will
1464 now set a breakpoint in build/gcc/expr.c, but not
1465 build/libcpp/expr.c.
1467 * The "info proc" and "generate-core-file" commands will now also
1468 work on remote targets connected to GDBserver on Linux.
1470 * The command "info catch" has been removed. It has been disabled
1471 since December 2007.
1473 * The "catch exception" and "catch assert" commands now accept
1474 a condition at the end of the command, much like the "break"
1475 command does. For instance:
1477 (gdb) catch exception Constraint_Error if Barrier = True
1479 Previously, it was possible to add a condition to such catchpoints,
1480 but it had to be done as a second step, after the catchpoint had been
1481 created, using the "condition" command.
1483 * The "info static-tracepoint-marker" command will now also work on
1484 native Linux targets with in-process agent.
1486 * GDB can now set breakpoints on inlined functions.
1488 * The .gdb_index section has been updated to include symbols for
1489 inlined functions. GDB will ignore older .gdb_index sections by
1490 default, which could cause symbol files to be loaded more slowly
1491 until their .gdb_index sections can be recreated. The new command
1492 "set use-deprecated-index-sections on" will cause GDB to use any older
1493 .gdb_index sections it finds. This will restore performance, but the
1494 ability to set breakpoints on inlined functions will be lost in symbol
1495 files with older .gdb_index sections.
1497 The .gdb_index section has also been updated to record more information
1498 about each symbol. This speeds up the "info variables", "info functions"
1499 and "info types" commands when used with programs having the .gdb_index
1500 section, as well as speeding up debugging with shared libraries using
1501 the .gdb_index section.
1503 * Ada support for GDB/MI Variable Objects has been added.
1505 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1510 ** New command -info-os is the MI equivalent of "info os".
1512 ** Output logs ("set logging" and related) now include MI output.
1516 ** "set use-deprecated-index-sections on|off"
1517 "show use-deprecated-index-sections on|off"
1518 Controls the use of deprecated .gdb_index sections.
1520 ** "catch load" and "catch unload" can be used to stop when a shared
1521 library is loaded or unloaded, respectively.
1523 ** "enable count" can be used to auto-disable a breakpoint after
1526 ** "info vtbl" can be used to show the virtual method tables for
1527 C++ and Java objects.
1529 ** "explore" and its sub commands "explore value" and "explore type"
1530 can be used to recursively explore values and types of
1531 expressions. These commands are available only if GDB is
1532 configured with '--with-python'.
1534 ** "info auto-load" shows status of all kinds of auto-loaded files,
1535 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1536 sequences of commands files, "info auto-load python-scripts"
1537 shows status of auto-loading Python script files,
1538 "info auto-load local-gdbinit" shows status of loading init file
1539 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1540 status of inferior specific thread debugging shared library loading.
1542 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1543 and "show auto-load-scripts" commands have been deprecated, use their
1544 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1545 and "show auto-load python-scripts" counterparts instead.
1547 ** "dprintf location,format,args..." creates a dynamic printf, which
1548 is basically a breakpoint that does a printf and immediately
1549 resumes your program's execution, so it is like a printf that you
1550 can insert dynamically at runtime instead of at compiletime.
1552 ** "set print symbol"
1554 Controls whether GDB attempts to display the symbol, if any,
1555 corresponding to addresses it prints. This defaults to "on", but
1556 you can set it to "off" to restore GDB's previous behavior.
1558 * Deprecated commands
1560 ** For the Renesas Super-H architecture, the "regs" command has been
1561 deprecated, and "info all-registers" should be used instead.
1565 Renesas RL78 rl78-*-elf
1566 HP OpenVMS ia64 ia64-hp-openvms*
1568 * GDBserver supports evaluation of breakpoint conditions. When
1569 support is advertised by GDBserver, GDB may be told to send the
1570 breakpoint conditions in bytecode form to GDBserver. GDBserver
1571 will only report the breakpoint trigger to GDB when its condition
1576 set mips compression
1577 show mips compression
1578 Select the compressed ISA encoding used in functions that have no symbol
1579 information available. The encoding can be set to either of:
1582 and is updated automatically from ELF file flags if available.
1584 set breakpoint condition-evaluation
1585 show breakpoint condition-evaluation
1586 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1587 GDBserver ("target"). Default option "auto" chooses the most efficient
1589 This option can improve debugger efficiency depending on the speed of the
1593 Disable auto-loading globally.
1596 Show auto-loading setting of all kinds of auto-loaded files.
1598 set auto-load gdb-scripts on|off
1599 show auto-load gdb-scripts
1600 Control auto-loading of GDB canned sequences of commands files.
1602 set auto-load python-scripts on|off
1603 show auto-load python-scripts
1604 Control auto-loading of Python script files.
1606 set auto-load local-gdbinit on|off
1607 show auto-load local-gdbinit
1608 Control loading of init file (.gdbinit) from current directory.
1610 set auto-load libthread-db on|off
1611 show auto-load libthread-db
1612 Control auto-loading of inferior specific thread debugging shared library.
1614 set auto-load scripts-directory <dir1>[:<dir2>...]
1615 show auto-load scripts-directory
1616 Set a list of directories from which to load auto-loaded scripts.
1617 Automatically loaded Python scripts and GDB scripts are located in one
1618 of the directories listed by this option.
1619 The delimiter (':' above) may differ according to the host platform.
1621 set auto-load safe-path <dir1>[:<dir2>...]
1622 show auto-load safe-path
1623 Set a list of directories from which it is safe to auto-load files.
1624 The delimiter (':' above) may differ according to the host platform.
1626 set debug auto-load on|off
1627 show debug auto-load
1628 Control display of debugging info for auto-loading the files above.
1630 set dprintf-style gdb|call|agent
1632 Control the way in which a dynamic printf is performed; "gdb"
1633 requests a GDB printf command, while "call" causes dprintf to call a
1634 function in the inferior. "agent" requests that the target agent
1635 (such as GDBserver) do the printing.
1637 set dprintf-function <expr>
1638 show dprintf-function
1639 set dprintf-channel <expr>
1640 show dprintf-channel
1641 Set the function and optional first argument to the call when using
1642 the "call" style of dynamic printf.
1644 set disconnected-dprintf on|off
1645 show disconnected-dprintf
1646 Control whether agent-style dynamic printfs continue to be in effect
1647 after GDB disconnects.
1649 * New configure options
1651 --with-auto-load-dir
1652 Configure default value for the 'set auto-load scripts-directory'
1653 setting above. It defaults to '$debugdir:$datadir/auto-load',
1654 $debugdir representing global debugging info directories (available
1655 via 'show debug-file-directory') and $datadir representing GDB's data
1656 directory (available via 'show data-directory').
1658 --with-auto-load-safe-path
1659 Configure default value for the 'set auto-load safe-path' setting
1660 above. It defaults to the --with-auto-load-dir setting.
1662 --without-auto-load-safe-path
1663 Set 'set auto-load safe-path' to '/', effectively disabling this
1666 * New remote packets
1668 z0/z1 conditional breakpoints extension
1670 The z0/z1 breakpoint insertion packets have been extended to carry
1671 a list of conditional expressions over to the remote stub depending on the
1672 condition evaluation mode. The use of this extension can be controlled
1673 via the "set remote conditional-breakpoints-packet" command.
1677 Specify the signals which the remote stub may pass to the debugged
1678 program without GDB involvement.
1680 * New command line options
1682 --init-command=FILE, -ix Like --command, -x but execute it
1683 before loading inferior.
1684 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1685 execute it before loading inferior.
1687 *** Changes in GDB 7.4
1689 * GDB now handles ambiguous linespecs more consistently; the existing
1690 FILE:LINE support has been expanded to other types of linespecs. A
1691 breakpoint will now be set on all matching locations in all
1692 inferiors, and locations will be added or removed according to
1695 * GDB now allows you to skip uninteresting functions and files when
1696 stepping with the "skip function" and "skip file" commands.
1698 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1699 and "show remote hardware-watchpoint-length-limit". These allows to
1700 set or show the maximum length limit (in bytes) of a remote
1701 target hardware watchpoint.
1703 This allows e.g. to use "unlimited" hardware watchpoints with the
1704 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1705 watchpoints are slower than real hardware watchpoints but are
1706 significantly faster than gdb software watchpoints.
1710 ** The register_pretty_printer function in module gdb.printing now takes
1711 an optional `replace' argument. If True, the new printer replaces any
1714 ** The "maint set python print-stack on|off" command has been
1715 deprecated and will be deleted in GDB 7.5.
1716 A new command: "set python print-stack none|full|message" has
1717 replaced it. Additionally, the default for "print-stack" is
1718 now "message", which just prints the error message without
1721 ** A prompt substitution hook (prompt_hook) is now available to the
1724 ** A new Python module, gdb.prompt has been added to the GDB Python
1725 modules library. This module provides functionality for
1726 escape sequences in prompts (used by set/show
1727 extended-prompt). These escape sequences are replaced by their
1728 corresponding value.
1730 ** Python commands and convenience-functions located in
1731 'data-directory'/python/gdb/command and
1732 'data-directory'/python/gdb/function are now automatically loaded
1735 ** Blocks now provide four new attributes. global_block and
1736 static_block will return the global and static blocks
1737 respectively. is_static and is_global are boolean attributes
1738 that indicate if the block is one of those two types.
1740 ** Symbols now provide the "type" attribute, the type of the symbol.
1742 ** The "gdb.breakpoint" function has been deprecated in favor of
1745 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1746 of a function. This class is based on the "finish" command
1747 available in the CLI.
1749 ** Type objects for struct and union types now allow access to
1750 the fields using standard Python dictionary (mapping) methods.
1751 For example, "some_type['myfield']" now works, as does
1752 "some_type.items()".
1754 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1757 ** A new function, "deep_items" has been added to the gdb.types
1758 module in the GDB Python modules library. This function returns
1759 an iterator over the fields of a struct or union type. Unlike
1760 the standard Python "iteritems" method, it will recursively traverse
1761 any anonymous fields.
1765 ** "*stopped" events can report several new "reason"s, such as
1768 ** Breakpoint changes are now notified using new async records, like
1769 "=breakpoint-modified".
1771 ** New command -ada-task-info.
1773 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1774 $sdir specifies the default system locations of shared libraries.
1775 $pdir specifies the directory where the libpthread used by the application
1778 GDB no longer looks in $sdir and $pdir after it has searched the directories
1779 mentioned in libthread-db-search-path. If you want to search those
1780 directories, they must be specified in libthread-db-search-path.
1781 The default value of libthread-db-search-path on GNU/Linux and Solaris
1782 systems is now "$sdir:$pdir".
1784 $pdir is not supported by gdbserver, it is currently ignored.
1785 $sdir is supported by gdbserver.
1787 * New configure option --with-iconv-bin.
1788 When using the internationalization support like the one in the GNU C
1789 library, GDB will invoke the "iconv" program to get a list of supported
1790 character sets. If this program lives in a non-standard location, one can
1791 use this option to specify where to find it.
1793 * When natively debugging programs on PowerPC BookE processors running
1794 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1795 watchpoints, which specify a mask in addition to an address to watch.
1796 The mask specifies that some bits of an address (the bits which are
1797 reset in the mask) should be ignored when matching the address accessed
1798 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1799 section in the user manual for more details.
1801 * The new option --once causes GDBserver to stop listening for connections once
1802 the first connection is made. The listening port used by GDBserver will
1803 become available after that.
1805 * New commands "info macros" and "alias" have been added.
1807 * New function parameters suffix @entry specifies value of function parameter
1808 at the time the function got called. Entry values are available only since
1814 "!" is now an alias of the "shell" command.
1815 Note that no space is needed between "!" and SHELL COMMAND.
1819 watch EXPRESSION mask MASK_VALUE
1820 The watch command now supports the mask argument which allows creation
1821 of masked watchpoints, if the current architecture supports this feature.
1823 info auto-load-scripts [REGEXP]
1824 This command was formerly named "maintenance print section-scripts".
1825 It is now generally useful and is no longer a maintenance-only command.
1827 info macro [-all] [--] MACRO
1828 The info macro command has new options `-all' and `--'. The first for
1829 printing all definitions of a macro. The second for explicitly specifying
1830 the end of arguments and the beginning of the macro name in case the macro
1831 name starts with a hyphen.
1833 collect[/s] EXPRESSIONS
1834 The tracepoint collect command now takes an optional modifier "/s"
1835 that directs it to dereference pointer-to-character types and
1836 collect the bytes of memory up to a zero byte. The behavior is
1837 similar to what you see when you use the regular print command on a
1838 string. An optional integer following the "/s" sets a bound on the
1839 number of bytes that will be collected.
1842 The trace start command now interprets any supplied arguments as a
1843 note to be recorded with the trace run, with an effect similar to
1844 setting the variable trace-notes.
1847 The trace stop command now interprets any arguments as a note to be
1848 mentioned along with the tstatus report that the trace was stopped
1849 with a command. The effect is similar to setting the variable
1852 * Tracepoints can now be enabled and disabled at any time after a trace
1853 experiment has been started using the standard "enable" and "disable"
1854 commands. It is now possible to start a trace experiment with no enabled
1855 tracepoints; GDB will display a warning, but will allow the experiment to
1856 begin, assuming that tracepoints will be enabled as needed while the trace
1859 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1860 locations with 4-byte instructions, when they were previously
1861 limited to locations with instructions of 5 bytes or longer.
1865 set debug dwarf2-read
1866 show debug dwarf2-read
1867 Turns on or off display of debugging messages related to reading
1868 DWARF debug info. The default is off.
1870 set debug symtab-create
1871 show debug symtab-create
1872 Turns on or off display of debugging messages related to symbol table
1873 creation. The default is off.
1876 show extended-prompt
1877 Set the GDB prompt, and allow escape sequences to be inserted to
1878 display miscellaneous information (see 'help set extended-prompt'
1879 for the list of sequences). This prompt (and any information
1880 accessed through the escape sequences) is updated every time the
1881 prompt is displayed.
1883 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1884 show print entry-values
1885 Set printing of frame argument values at function entry. In some cases
1886 GDB can determine the value of function argument which was passed by the
1887 function caller, even if the value was modified inside the called function.
1889 set debug entry-values
1890 show debug entry-values
1891 Control display of debugging info for determining frame argument values at
1892 function entry and virtual tail call frames.
1894 set basenames-may-differ
1895 show basenames-may-differ
1896 Set whether a source file may have multiple base names.
1897 (A "base name" is the name of a file with the directory part removed.
1898 Example: The base name of "/home/user/hello.c" is "hello.c".)
1899 If set, GDB will canonicalize file names (e.g., expand symlinks)
1900 before comparing them. Canonicalization is an expensive operation,
1901 but it allows the same file be known by more than one base name.
1902 If not set (the default), all source files are assumed to have just
1903 one base name, and gdb will do file name comparisons more efficiently.
1909 Set a user name and notes for the current and any future trace runs.
1910 This is useful for long-running and/or disconnected traces, to
1911 inform others (or yourself) as to who is running the trace, supply
1912 contact information, or otherwise explain what is going on.
1914 set trace-stop-notes
1915 show trace-stop-notes
1916 Set a note attached to the trace run, that is displayed when the
1917 trace has been stopped by a tstop command. This is useful for
1918 instance as an explanation, if you are stopping a trace run that was
1919 started by someone else.
1921 * New remote packets
1925 Dynamically enable a tracepoint in a started trace experiment.
1929 Dynamically disable a tracepoint in a started trace experiment.
1933 Set the user and notes of the trace run.
1937 Query the current status of a tracepoint.
1941 Query the minimum length of instruction at which a fast tracepoint may
1944 * Dcache size (number of lines) and line-size are now runtime-configurable
1945 via "set dcache line" and "set dcache line-size" commands.
1949 Texas Instruments TMS320C6x tic6x-*-*
1953 Renesas RL78 rl78-*-elf
1955 *** Changes in GDB 7.3.1
1957 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1959 *** Changes in GDB 7.3
1961 * GDB has a new command: "thread find [REGEXP]".
1962 It finds the thread id whose name, target id, or thread extra info
1963 matches the given regular expression.
1965 * The "catch syscall" command now works on mips*-linux* targets.
1967 * The -data-disassemble MI command now supports modes 2 and 3 for
1968 dumping the instruction opcodes.
1970 * New command line options
1972 -data-directory DIR Specify DIR as the "data-directory".
1973 This is mostly for testing purposes.
1975 * The "maint set python auto-load on|off" command has been renamed to
1976 "set auto-load-scripts on|off".
1978 * GDB has a new command: "set directories".
1979 It is like the "dir" command except that it replaces the
1980 source path list instead of augmenting it.
1982 * GDB now understands thread names.
1984 On GNU/Linux, "info threads" will display the thread name as set by
1985 prctl or pthread_setname_np.
1987 There is also a new command, "thread name", which can be used to
1988 assign a name internally for GDB to display.
1991 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1992 has been integrated into GDB.
1996 ** The function gdb.Write now accepts an optional keyword 'stream'.
1997 This keyword, when provided, will direct the output to either
1998 stdout, stderr, or GDB's logging output.
2000 ** Parameters can now be be sub-classed in Python, and in particular
2001 you may implement the get_set_doc and get_show_doc functions.
2002 This improves how Parameter set/show documentation is processed
2003 and allows for more dynamic content.
2005 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2006 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2007 have an is_valid method.
2009 ** Breakpoints can now be sub-classed in Python, and in particular
2010 you may implement a 'stop' function that is executed each time
2011 the inferior reaches that breakpoint.
2013 ** New function gdb.lookup_global_symbol looks up a global symbol.
2015 ** GDB values in Python are now callable if the value represents a
2016 function. For example, if 'some_value' represents a function that
2017 takes two integer parameters and returns a value, you can call
2018 that function like so:
2020 result = some_value (10,20)
2022 ** Module gdb.types has been added.
2023 It contains a collection of utilities for working with gdb.Types objects:
2024 get_basic_type, has_field, make_enum_dict.
2026 ** Module gdb.printing has been added.
2027 It contains utilities for writing and registering pretty-printers.
2028 New classes: PrettyPrinter, SubPrettyPrinter,
2029 RegexpCollectionPrettyPrinter.
2030 New function: register_pretty_printer.
2032 ** New commands "info pretty-printers", "enable pretty-printer" and
2033 "disable pretty-printer" have been added.
2035 ** gdb.parameter("directories") is now available.
2037 ** New function gdb.newest_frame returns the newest frame in the
2040 ** The gdb.InferiorThread class has a new "name" attribute. This
2041 holds the thread's name.
2043 ** Python Support for Inferior events.
2044 Python scripts can add observers to be notified of events
2045 occurring in the process being debugged.
2046 The following events are currently supported:
2047 - gdb.events.cont Continue event.
2048 - gdb.events.exited Inferior exited event.
2049 - gdb.events.stop Signal received, and Breakpoint hit events.
2053 ** GDB now puts template parameters in scope when debugging in an
2054 instantiation. For example, if you have:
2056 template<int X> int func (void) { return X; }
2058 then if you step into func<5>, "print X" will show "5". This
2059 feature requires proper debuginfo support from the compiler; it
2060 was added to GCC 4.5.
2062 ** The motion commands "next", "finish", "until", and "advance" now
2063 work better when exceptions are thrown. In particular, GDB will
2064 no longer lose control of the inferior; instead, the GDB will
2065 stop the inferior at the point at which the exception is caught.
2066 This functionality requires a change in the exception handling
2067 code that was introduced in GCC 4.5.
2069 * GDB now follows GCC's rules on accessing volatile objects when
2070 reading or writing target state during expression evaluation.
2071 One notable difference to prior behavior is that "print x = 0"
2072 no longer generates a read of x; the value of the assignment is
2073 now always taken directly from the value being assigned.
2075 * GDB now has some support for using labels in the program's source in
2076 linespecs. For instance, you can use "advance label" to continue
2077 execution to a label.
2079 * GDB now has support for reading and writing a new .gdb_index
2080 section. This section holds a fast index of DWARF debugging
2081 information and can be used to greatly speed up GDB startup and
2082 operation. See the documentation for `save gdb-index' for details.
2084 * The "watch" command now accepts an optional "-location" argument.
2085 When used, this causes GDB to watch the memory referred to by the
2086 expression. Such a watchpoint is never deleted due to it going out
2089 * GDB now supports thread debugging of core dumps on GNU/Linux.
2091 GDB now activates thread debugging using the libthread_db library
2092 when debugging GNU/Linux core dumps, similarly to when debugging
2093 live processes. As a result, when debugging a core dump file, GDB
2094 is now able to display pthread_t ids of threads. For example, "info
2095 threads" shows the same output as when debugging the process when it
2096 was live. In earlier releases, you'd see something like this:
2099 * 1 LWP 6780 main () at main.c:10
2101 While now you see this:
2104 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2106 It is also now possible to inspect TLS variables when debugging core
2109 When debugging a core dump generated on a machine other than the one
2110 used to run GDB, you may need to point GDB at the correct
2111 libthread_db library with the "set libthread-db-search-path"
2112 command. See the user manual for more details on this command.
2114 * When natively debugging programs on PowerPC BookE processors running
2115 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2116 which stop execution of the inferior whenever it executes an instruction
2117 at any address within the specified range. See the "PowerPC Embedded"
2118 section in the user manual for more details.
2120 * New features in the GDB remote stub, GDBserver
2122 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2123 and i686 LynxOS (version 5.x).
2125 ** GDBserver is now supported on Blackfin Linux.
2127 * New native configurations
2129 ia64 HP-UX ia64-*-hpux*
2133 Analog Devices, Inc. Blackfin Processor bfin-*
2135 * Ada task switching is now supported on sparc-elf targets when
2136 debugging a program using the Ravenscar Profile. For more information,
2137 see the "Tasking Support when using the Ravenscar Profile" section
2138 in the GDB user manual.
2140 * Guile support was removed.
2142 * New features in the GNU simulator
2144 ** The --map-info flag lists all known core mappings.
2146 ** CFI flashes may be simulated via the "cfi" device.
2148 *** Changes in GDB 7.2
2150 * Shared library support for remote targets by default
2152 When GDB is configured for a generic, non-OS specific target, like
2153 for example, --target=arm-eabi or one of the many *-*-elf targets,
2154 GDB now queries remote stubs for loaded shared libraries using the
2155 `qXfer:libraries:read' packet. Previously, shared library support
2156 was always disabled for such configurations.
2160 ** Argument Dependent Lookup (ADL)
2162 In C++ ADL lookup directs function search to the namespaces of its
2163 arguments even if the namespace has not been imported.
2173 Here the compiler will search for `foo' in the namespace of 'b'
2174 and find A::foo. GDB now supports this. This construct is commonly
2175 used in the Standard Template Library for operators.
2177 ** Improved User Defined Operator Support
2179 In addition to member operators, GDB now supports lookup of operators
2180 defined in a namespace and imported with a `using' directive, operators
2181 defined in the global scope, operators imported implicitly from an
2182 anonymous namespace, and the ADL operators mentioned in the previous
2184 GDB now also supports proper overload resolution for all the previously
2185 mentioned flavors of operators.
2187 ** static const class members
2189 Printing of static const class members that are initialized in the
2190 class definition has been fixed.
2192 * Windows Thread Information Block access.
2194 On Windows targets, GDB now supports displaying the Windows Thread
2195 Information Block (TIB) structure. This structure is visible either
2196 by using the new command `info w32 thread-information-block' or, by
2197 dereferencing the new convenience variable named `$_tlb', a
2198 thread-specific pointer to the TIB. This feature is also supported
2199 when remote debugging using GDBserver.
2201 * Static tracepoints
2203 Static tracepoints are calls in the user program into a tracing
2204 library. One such library is a port of the LTTng kernel tracer to
2205 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2206 When debugging with GDBserver, GDB now supports combining the GDB
2207 tracepoint machinery with such libraries. For example: the user can
2208 use GDB to probe a static tracepoint marker (a call from the user
2209 program into the tracing library) with the new "strace" command (see
2210 "New commands" below). This creates a "static tracepoint" in the
2211 breakpoint list, that can be manipulated with the same feature set
2212 as fast and regular tracepoints. E.g., collect registers, local and
2213 global variables, collect trace state variables, and define
2214 tracepoint conditions. In addition, the user can collect extra
2215 static tracepoint marker specific data, by collecting the new
2216 $_sdata internal variable. When analyzing the trace buffer, you can
2217 inspect $_sdata like any other variable available to GDB. For more
2218 information, see the "Tracepoints" chapter in GDB user manual. New
2219 remote packets have been defined to support static tracepoints, see
2220 the "New remote packets" section below.
2222 * Better reconstruction of tracepoints after disconnected tracing
2224 GDB will attempt to download the original source form of tracepoint
2225 definitions when starting a trace run, and then will upload these
2226 upon reconnection to the target, resulting in a more accurate
2227 reconstruction of the tracepoints that are in use on the target.
2231 You can now exercise direct control over the ways that GDB can
2232 affect your program. For instance, you can disallow the setting of
2233 breakpoints, so that the program can run continuously (assuming
2234 non-stop mode). In addition, the "observer" variable is available
2235 to switch all of the different controls; in observer mode, GDB
2236 cannot affect the target's behavior at all, which is useful for
2237 tasks like diagnosing live systems in the field.
2239 * The new convenience variable $_thread holds the number of the
2242 * New remote packets
2246 Return the address of the Windows Thread Information Block of a given thread.
2250 In response to several of the tracepoint packets, the target may now
2251 also respond with a number of intermediate `qRelocInsn' request
2252 packets before the final result packet, to have GDB handle
2253 relocating an instruction to execute at a different address. This
2254 is particularly useful for stubs that support fast tracepoints. GDB
2255 reports support for this feature in the qSupported packet.
2259 List static tracepoint markers in the target program.
2263 List static tracepoint markers at a given address in the target
2266 qXfer:statictrace:read
2268 Read the static trace data collected (by a `collect $_sdata'
2269 tracepoint action). The remote stub reports support for this packet
2270 to gdb's qSupported query.
2274 Send the current settings of GDB's permission flags.
2278 Send part of the source (textual) form of a tracepoint definition,
2279 which includes location, conditional, and action list.
2281 * The source command now accepts a -s option to force searching for the
2282 script in the source search path even if the script name specifies
2285 * New features in the GDB remote stub, GDBserver
2287 - GDBserver now support tracepoints (including fast tracepoints, and
2288 static tracepoints). The feature is currently supported by the
2289 i386-linux and amd64-linux builds. See the "Tracepoints support
2290 in gdbserver" section in the manual for more information.
2292 GDBserver JIT compiles the tracepoint's conditional agent
2293 expression bytecode into native code whenever possible for low
2294 overhead dynamic tracepoints conditionals. For such tracepoints,
2295 an expression that examines program state is evaluated when the
2296 tracepoint is reached, in order to determine whether to capture
2297 trace data. If the condition is simple and false, processing the
2298 tracepoint finishes very quickly and no data is gathered.
2300 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2301 for static tracepoints support.
2303 - GDBserver now supports x86_64 Windows 64-bit debugging.
2305 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2306 it understands register description.
2308 * The --batch flag now disables pagination and queries.
2310 * X86 general purpose registers
2312 GDB now supports reading/writing byte, word and double-word x86
2313 general purpose registers directly. This means you can use, say,
2314 $ah or $ax to refer, respectively, to the byte register AH and
2315 16-bit word register AX that are actually portions of the 32-bit
2316 register EAX or 64-bit register RAX.
2318 * The `commands' command now accepts a range of breakpoints to modify.
2319 A plain `commands' following a command that creates multiple
2320 breakpoints affects all the breakpoints set by that command. This
2321 applies to breakpoints set by `rbreak', and also applies when a
2322 single `break' command creates multiple breakpoints (e.g.,
2323 breakpoints on overloaded c++ functions).
2325 * The `rbreak' command now accepts a filename specification as part of
2326 its argument, limiting the functions selected by the regex to those
2327 in the specified file.
2329 * Support for remote debugging Windows and SymbianOS shared libraries
2330 from Unix hosts has been improved. Non Windows GDB builds now can
2331 understand target reported file names that follow MS-DOS based file
2332 system semantics, such as file names that include drive letters and
2333 use the backslash character as directory separator. This makes it
2334 possible to transparently use the "set sysroot" and "set
2335 solib-search-path" on Unix hosts to point as host copies of the
2336 target's shared libraries. See the new command "set
2337 target-file-system-kind" described below, and the "Commands to
2338 specify files" section in the user manual for more information.
2342 eval template, expressions...
2343 Convert the values of one or more expressions under the control
2344 of the string template to a command line, and call it.
2346 set target-file-system-kind unix|dos-based|auto
2347 show target-file-system-kind
2348 Set or show the assumed file system kind for target reported file
2351 save breakpoints <filename>
2352 Save all current breakpoint definitions to a file suitable for use
2353 in a later debugging session. To read the saved breakpoint
2354 definitions, use the `source' command.
2356 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2359 info static-tracepoint-markers
2360 Display information about static tracepoint markers in the target.
2362 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2363 Define a static tracepoint by probing a marker at the given
2364 function, line, address, or marker ID.
2368 Enable and disable observer mode.
2370 set may-write-registers on|off
2371 set may-write-memory on|off
2372 set may-insert-breakpoints on|off
2373 set may-insert-tracepoints on|off
2374 set may-insert-fast-tracepoints on|off
2375 set may-interrupt on|off
2376 Set individual permissions for GDB effects on the target. Note that
2377 some of these settings can have undesirable or surprising
2378 consequences, particularly when changed in the middle of a session.
2379 For instance, disabling the writing of memory can prevent
2380 breakpoints from being inserted, cause single-stepping to fail, or
2381 even crash your program, if you disable after breakpoints have been
2382 inserted. However, GDB should not crash.
2384 set record memory-query on|off
2385 show record memory-query
2386 Control whether to stop the inferior if memory changes caused
2387 by an instruction cannot be recorded.
2392 The disassemble command now supports "start,+length" form of two arguments.
2396 ** GDB now provides a new directory location, called the python directory,
2397 where Python scripts written for GDB can be installed. The location
2398 of that directory is <data-directory>/python, where <data-directory>
2399 is the GDB data directory. For more details, see section `Scripting
2400 GDB using Python' in the manual.
2402 ** The GDB Python API now has access to breakpoints, symbols, symbol
2403 tables, program spaces, inferiors, threads and frame's code blocks.
2404 Additionally, GDB Parameters can now be created from the API, and
2405 manipulated via set/show in the CLI.
2407 ** New functions gdb.target_charset, gdb.target_wide_charset,
2408 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2410 ** New exception gdb.GdbError.
2412 ** Pretty-printers are now also looked up in the current program space.
2414 ** Pretty-printers can now be individually enabled and disabled.
2416 ** GDB now looks for names of Python scripts to auto-load in a
2417 special section named `.debug_gdb_scripts', in addition to looking
2418 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2420 * Tracepoint actions were unified with breakpoint commands. In particular,
2421 there are no longer differences in "info break" output for breakpoints and
2422 tracepoints and the "commands" command can be used for both tracepoints and
2423 regular breakpoints.
2427 ARM Symbian arm*-*-symbianelf*
2429 * D language support.
2430 GDB now supports debugging programs written in the D programming
2433 * GDB now supports the extended ptrace interface for PowerPC which is
2434 available since Linux kernel version 2.6.34. This automatically enables
2435 any hardware breakpoints and additional hardware watchpoints available in
2436 the processor. The old ptrace interface exposes just one hardware
2437 watchpoint and no hardware breakpoints.
2439 * GDB is now able to use the Data Value Compare (DVC) register available on
2440 embedded PowerPC processors to implement in hardware simple watchpoint
2441 conditions of the form:
2443 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2445 This works in native GDB running on Linux kernels with the extended ptrace
2446 interface mentioned above.
2448 *** Changes in GDB 7.1
2452 ** Namespace Support
2454 GDB now supports importing of namespaces in C++. This enables the
2455 user to inspect variables from imported namespaces. Support for
2456 namepace aliasing has also been added. So, if a namespace is
2457 aliased in the current scope (e.g. namepace C=A; ) the user can
2458 print variables using the alias (e.g. (gdb) print C::x).
2462 All known bugs relating to the printing of virtual base class were
2463 fixed. It is now possible to call overloaded static methods using a
2468 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2469 and reinterpret_cast<> are now handled by the C++ expression parser.
2473 Xilinx MicroBlaze microblaze-*-*
2478 Xilinx MicroBlaze microblaze
2481 * Multi-program debugging.
2483 GDB now has support for multi-program (a.k.a. multi-executable or
2484 multi-exec) debugging. This allows for debugging multiple inferiors
2485 simultaneously each running a different program under the same GDB
2486 session. See "Debugging Multiple Inferiors and Programs" in the
2487 manual for more information. This implied some user visible changes
2488 in the multi-inferior support. For example, "info inferiors" now
2489 lists inferiors that are not running yet or that have exited
2490 already. See also "New commands" and "New options" below.
2492 * New tracing features
2494 GDB's tracepoint facility now includes several new features:
2496 ** Trace state variables
2498 GDB tracepoints now include support for trace state variables, which
2499 are variables managed by the target agent during a tracing
2500 experiment. They are useful for tracepoints that trigger each
2501 other, so for instance one tracepoint can count hits in a variable,
2502 and then a second tracepoint has a condition that is true when the
2503 count reaches a particular value. Trace state variables share the
2504 $-syntax of GDB convenience variables, and can appear in both
2505 tracepoint actions and condition expressions. Use the "tvariable"
2506 command to create, and "info tvariables" to view; see "Trace State
2507 Variables" in the manual for more detail.
2511 GDB now includes an option for defining fast tracepoints, which
2512 targets may implement more efficiently, such as by installing a jump
2513 into the target agent rather than a trap instruction. The resulting
2514 speedup can be by two orders of magnitude or more, although the
2515 tradeoff is that some program locations on some target architectures
2516 might not allow fast tracepoint installation, for instance if the
2517 instruction to be replaced is shorter than the jump. To request a
2518 fast tracepoint, use the "ftrace" command, with syntax identical to
2519 the regular trace command.
2521 ** Disconnected tracing
2523 It is now possible to detach GDB from the target while it is running
2524 a trace experiment, then reconnect later to see how the experiment
2525 is going. In addition, a new variable disconnected-tracing lets you
2526 tell the target agent whether to continue running a trace if the
2527 connection is lost unexpectedly.
2531 GDB now has the ability to save the trace buffer into a file, and
2532 then use that file as a target, similarly to you can do with
2533 corefiles. You can select trace frames, print data that was
2534 collected in them, and use tstatus to display the state of the
2535 tracing run at the moment that it was saved. To create a trace
2536 file, use "tsave <filename>", and to use it, do "target tfile
2539 ** Circular trace buffer
2541 You can ask the target agent to handle the trace buffer as a
2542 circular buffer, discarding the oldest trace frames to make room for
2543 newer ones, by setting circular-trace-buffer to on. This feature may
2544 not be available for all target agents.
2549 The disassemble command, when invoked with two arguments, now requires
2550 the arguments to be comma-separated.
2553 The info variables command now displays variable definitions. Files
2554 which only declare a variable are not shown.
2557 The source command is now capable of sourcing Python scripts.
2558 This feature is dependent on the debugger being build with Python
2561 Related to this enhancement is also the introduction of a new command
2562 "set script-extension" (see below).
2564 * New commands (for set/show, see "New options" below)
2566 record save [<FILENAME>]
2567 Save a file (in core file format) containing the process record
2568 execution log for replay debugging at a later time.
2570 record restore <FILENAME>
2571 Restore the process record execution log that was saved at an
2572 earlier time, for replay debugging.
2574 add-inferior [-copies <N>] [-exec <FILENAME>]
2577 clone-inferior [-copies <N>] [ID]
2578 Make a new inferior ready to execute the same program another
2579 inferior has loaded.
2584 maint info program-spaces
2585 List the program spaces loaded into GDB.
2587 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2588 show remote interrupt-sequence
2589 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2590 as the sequence to the remote target in order to interrupt the execution.
2591 Ctrl-C is a default. Some system prefers BREAK which is high level of
2592 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2593 Magic SysRq g. It is BREAK signal and character 'g'.
2595 set remote interrupt-on-connect [on | off]
2596 show remote interrupt-on-connect
2597 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2598 remote target when gdb connects to it. This is needed when you debug
2601 set remotebreak [on | off]
2603 Deprecated. Use "set/show remote interrupt-sequence" instead.
2605 tvariable $NAME [ = EXP ]
2606 Create or modify a trace state variable.
2609 List trace state variables and their values.
2611 delete tvariable $NAME ...
2612 Delete one or more trace state variables.
2615 Evaluate the given expressions without collecting anything into the
2616 trace buffer. (Valid in tracepoint actions only.)
2618 ftrace FN / FILE:LINE / *ADDR
2619 Define a fast tracepoint at the given function, line, or address.
2621 * New expression syntax
2623 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2624 GDB now parses 0b101010 identically with 42.
2628 set follow-exec-mode new|same
2629 show follow-exec-mode
2630 Control whether GDB reuses the same inferior across an exec call or
2631 creates a new one. This is useful to be able to restart the old
2632 executable after the inferior having done an exec call.
2634 set default-collect EXPR, ...
2635 show default-collect
2636 Define a list of expressions to be collected at each tracepoint.
2637 This is a useful way to ensure essential items are not overlooked,
2638 such as registers or a critical global variable.
2640 set disconnected-tracing
2641 show disconnected-tracing
2642 If set to 1, the target is instructed to continue tracing if it
2643 loses its connection to GDB. If 0, the target is to stop tracing
2646 set circular-trace-buffer
2647 show circular-trace-buffer
2648 If set to on, the target is instructed to use a circular trace buffer
2649 and discard the oldest trace frames instead of stopping the trace due
2650 to a full trace buffer. If set to off, the trace stops when the buffer
2651 fills up. Some targets may not support this.
2653 set script-extension off|soft|strict
2654 show script-extension
2655 If set to "off", the debugger does not perform any script language
2656 recognition, and all sourced files are assumed to be GDB scripts.
2657 If set to "soft" (the default), files are sourced according to
2658 filename extension, falling back to GDB scripts if the first
2660 If set to "strict", files are sourced according to filename extension.
2662 set ada trust-PAD-over-XVS on|off
2663 show ada trust-PAD-over-XVS
2664 If off, activate a workaround against a bug in the debugging information
2665 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2666 the GCC sources for more information about the GNAT encoding and
2667 PAD types in particular). It is always safe to set this option to
2668 off, but this introduces a slight performance penalty. The default
2671 * Python API Improvements
2673 ** GDB provides the new class gdb.LazyString. This is useful in
2674 some pretty-printing cases. The new method gdb.Value.lazy_string
2675 provides a simple way to create objects of this type.
2677 ** The fields returned by gdb.Type.fields now have an
2678 `is_base_class' attribute.
2680 ** The new method gdb.Type.range returns the range of an array type.
2682 ** The new method gdb.parse_and_eval can be used to parse and
2683 evaluate an expression.
2685 * New remote packets
2688 Define a trace state variable.
2691 Get the current value of a trace state variable.
2694 Set desired tracing behavior upon disconnection.
2697 Set the trace buffer to be linear or circular.
2700 Get data about the tracepoints currently in use.
2704 Process record now works correctly with hardware watchpoints.
2706 Multiple bug fixes have been made to the mips-irix port, making it
2707 much more reliable. In particular:
2708 - Debugging threaded applications is now possible again. Previously,
2709 GDB would hang while starting the program, or while waiting for
2710 the program to stop at a breakpoint.
2711 - Attaching to a running process no longer hangs.
2712 - An error occurring while loading a core file has been fixed.
2713 - Changing the value of the PC register now works again. This fixes
2714 problems observed when using the "jump" command, or when calling
2715 a function from GDB, or even when assigning a new value to $pc.
2716 - With the "finish" and "return" commands, the return value for functions
2717 returning a small array is now correctly printed.
2718 - It is now possible to break on shared library code which gets executed
2719 during a shared library init phase (code executed while executing
2720 their .init section). Previously, the breakpoint would have no effect.
2721 - GDB is now able to backtrace through the signal handler for
2722 non-threaded programs.
2724 PIE (Position Independent Executable) programs debugging is now supported.
2725 This includes debugging execution of PIC (Position Independent Code) shared
2726 libraries although for that, it should be possible to run such libraries as an
2729 *** Changes in GDB 7.0
2731 * GDB now has an interface for JIT compilation. Applications that
2732 dynamically generate code can create symbol files in memory and register
2733 them with GDB. For users, the feature should work transparently, and
2734 for JIT developers, the interface is documented in the GDB manual in the
2735 "JIT Compilation Interface" chapter.
2737 * Tracepoints may now be conditional. The syntax is as for
2738 breakpoints; either an "if" clause appended to the "trace" command,
2739 or the "condition" command is available. GDB sends the condition to
2740 the target for evaluation using the same bytecode format as is used
2741 for tracepoint actions.
2743 * The disassemble command now supports: an optional /r modifier, print the
2744 raw instructions in hex as well as in symbolic form, and an optional /m
2745 modifier to print mixed source+assembly.
2747 * Process record and replay
2749 In a architecture environment that supports ``process record and
2750 replay'', ``process record and replay'' target can record a log of
2751 the process execution, and replay it with both forward and reverse
2754 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2755 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2756 set execution-direction {forward|reverse}, for targets that support
2759 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2760 feature is available with a native GDB running on kernel version
2763 * GDB now has support for multi-byte and wide character sets on the
2764 target. Strings whose character type is wchar_t, char16_t, or
2765 char32_t are now correctly printed. GDB supports wide- and unicode-
2766 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2767 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2768 `printf'. This feature requires iconv to work properly; if your
2769 system does not have a working iconv, GDB can use GNU libiconv. See
2770 the installation instructions for more information.
2772 * GDB now supports automatic retrieval of shared library files from
2773 remote targets. To use this feature, specify a system root that begins
2774 with the `remote:' prefix, either via the `set sysroot' command or via
2775 the `--with-sysroot' configure-time option.
2777 * "info sharedlibrary" now takes an optional regex of libraries to show,
2778 and it now reports if a shared library has no debugging information.
2780 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2781 now complete on file names.
2783 * When completing in expressions, gdb will attempt to limit
2784 completions to allowable structure or union fields, where appropriate.
2785 For instance, consider:
2787 # struct example { int f1; double f2; };
2788 # struct example variable;
2791 If the user types TAB at the end of this command line, the available
2792 completions will be "f1" and "f2".
2794 * Inlined functions are now supported. They show up in backtraces, and
2795 the "step", "next", and "finish" commands handle them automatically.
2797 * GDB now supports the token-splicing (##) and stringification (#)
2798 operators when expanding macros. It also supports variable-arity
2801 * GDB now supports inspecting extra signal information, exported by
2802 the new $_siginfo convenience variable. The feature is currently
2803 implemented on linux ARM, i386 and amd64.
2805 * GDB can now display the VFP floating point registers and NEON vector
2806 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2807 can provide these registers (requires Linux 2.6.30 or later). Remote
2808 and simulator targets may also provide them.
2810 * New remote packets
2813 Search memory for a sequence of bytes.
2816 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2817 operation over reliable transport links. Use of this packet is
2818 controlled by the `set remote noack-packet' command.
2821 Kill the process with the specified process ID. Use this in preference
2822 to `k' when multiprocess protocol extensions are supported.
2825 Obtains additional operating system information
2829 Read or write additional signal information.
2831 * Removed remote protocol undocumented extension
2833 An undocumented extension to the remote protocol's `S' stop reply
2834 packet that permited the stub to pass a process id was removed.
2835 Remote servers should use the `T' stop reply packet instead.
2837 * GDB now supports multiple function calling conventions according to the
2838 DWARF-2 DW_AT_calling_convention function attribute.
2840 * The SH target utilizes the aforementioned change to distinguish between gcc
2841 and Renesas calling convention. It also adds the new CLI commands
2842 `set/show sh calling-convention'.
2844 * GDB can now read compressed debug sections, as produced by GNU gold
2845 with the --compress-debug-sections=zlib flag.
2847 * 64-bit core files are now supported on AIX.
2849 * Thread switching is now supported on Tru64.
2851 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2852 which will be allocated using malloc later in program execution.
2854 * The qXfer:libraries:read remote procotol packet now allows passing a
2855 list of section offsets.
2857 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2858 conditions handling signals delivered during attach or thread creation
2859 have also been fixed.
2861 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2862 From the user's standpoint, all unqualified instances of True and False
2863 are treated as the standard definitions, regardless of context.
2865 * GDB now parses C++ symbol and type names more flexibly. For
2868 template<typename T> class C { };
2871 GDB will now correctly handle all of:
2873 ptype C<char const *>
2874 ptype C<char const*>
2875 ptype C<const char *>
2876 ptype C<const char*>
2878 * New features in the GDB remote stub, gdbserver
2880 - The "--wrapper" command-line argument tells gdbserver to use a
2881 wrapper program to launch programs for debugging.
2883 - On PowerPC and S/390 targets, it is now possible to use a single
2884 gdbserver executable to debug both 32-bit and 64-bit programs.
2885 (This requires gdbserver itself to be built as a 64-bit executable.)
2887 - gdbserver uses the new noack protocol mode for TCP connections to
2888 reduce communications latency, if also supported and enabled in GDB.
2890 - Support for the sparc64-linux-gnu target is now included in
2893 - The amd64-linux build of gdbserver now supports debugging both
2894 32-bit and 64-bit programs.
2896 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2897 now support hardware watchpoints, and will use them automatically
2902 GDB now has support for scripting using Python. Whether this is
2903 available is determined at configure time.
2905 New GDB commands can now be written in Python.
2907 * Ada tasking support
2909 Ada tasks can now be inspected in GDB. The following commands have
2913 Print the list of Ada tasks.
2915 Print detailed information about task number N.
2917 Print the task number of the current task.
2919 Switch the context of debugging to task number N.
2921 * Support for user-defined prefixed commands. The "define" command can
2922 add new commands to existing prefixes, e.g. "target".
2924 * Multi-inferior, multi-process debugging.
2926 GDB now has generalized support for multi-inferior debugging. See
2927 "Debugging Multiple Inferiors" in the manual for more information.
2928 Although availability still depends on target support, the command
2929 set is more uniform now. The GNU/Linux specific multi-forks support
2930 has been migrated to this new framework. This implied some user
2931 visible changes; see "New commands" and also "Removed commands"
2934 * Target descriptions can now describe the target OS ABI. See the
2935 "Target Description Format" section in the user manual for more
2938 * Target descriptions can now describe "compatible" architectures
2939 to indicate that the target can execute applications for a different
2940 architecture in addition to those for the main target architecture.
2941 See the "Target Description Format" section in the user manual for
2944 * Multi-architecture debugging.
2946 GDB now includes general supports for debugging applications on
2947 hybrid systems that use more than one single processor architecture
2948 at the same time. Each such hybrid architecture still requires
2949 specific support to be added. The only hybrid architecture supported
2950 in this version of GDB is the Cell Broadband Engine.
2952 * GDB now supports integrated debugging of Cell/B.E. applications that
2953 use both the PPU and SPU architectures. To enable support for hybrid
2954 Cell/B.E. debugging, you need to configure GDB to support both the
2955 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2956 --enable-targets configure option.
2958 * Non-stop mode debugging.
2960 For some targets, GDB now supports an optional mode of operation in
2961 which you can examine stopped threads while other threads continue
2962 to execute freely. This is referred to as non-stop mode, with the
2963 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2964 section in the user manual for more information.
2966 To be able to support remote non-stop debugging, a remote stub needs
2967 to implement the non-stop mode remote protocol extensions, as
2968 described in the "Remote Non-Stop" section of the user manual. The
2969 GDB remote stub, gdbserver, has been adjusted to support these
2970 extensions on linux targets.
2972 * New commands (for set/show, see "New options" below)
2974 catch syscall [NAME(S) | NUMBER(S)]
2975 Catch system calls. Arguments, which should be names of system
2976 calls or their numbers, mean catch only those syscalls. Without
2977 arguments, every syscall will be caught. When the inferior issues
2978 any of the specified syscalls, GDB will stop and announce the system
2979 call, both when it is called and when its call returns. This
2980 feature is currently available with a native GDB running on the
2981 Linux Kernel, under the following architectures: x86, x86_64,
2982 PowerPC and PowerPC64.
2984 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2986 Search memory for a sequence of bytes.
2988 maint set python print-stack
2989 maint show python print-stack
2990 Show a stack trace when an error is encountered in a Python script.
2993 Invoke CODE by passing it to the Python interpreter.
2998 These allow macros to be defined, undefined, and listed
3002 Show operating system information about processes.
3005 List the inferiors currently under GDB's control.
3008 Switch focus to inferior number NUM.
3011 Detach from inferior number NUM.
3014 Kill inferior number NUM.
3018 set spu stop-on-load
3019 show spu stop-on-load
3020 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3022 set spu auto-flush-cache
3023 show spu auto-flush-cache
3024 Control whether to automatically flush the software-managed cache
3025 during Cell/B.E. debugging.
3027 set sh calling-convention
3028 show sh calling-convention
3029 Control the calling convention used when calling SH target functions.
3032 show debug timestamp
3033 Control display of timestamps with GDB debugging output.
3035 set disassemble-next-line
3036 show disassemble-next-line
3037 Control display of disassembled source lines or instructions when
3040 set remote noack-packet
3041 show remote noack-packet
3042 Set/show the use of remote protocol QStartNoAckMode packet. See above
3043 under "New remote packets."
3045 set remote query-attached-packet
3046 show remote query-attached-packet
3047 Control use of remote protocol `qAttached' (query-attached) packet.
3049 set remote read-siginfo-object
3050 show remote read-siginfo-object
3051 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3054 set remote write-siginfo-object
3055 show remote write-siginfo-object
3056 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3059 set remote reverse-continue
3060 show remote reverse-continue
3061 Control use of remote protocol 'bc' (reverse-continue) packet.
3063 set remote reverse-step
3064 show remote reverse-step
3065 Control use of remote protocol 'bs' (reverse-step) packet.
3067 set displaced-stepping
3068 show displaced-stepping
3069 Control displaced stepping mode. Displaced stepping is a way to
3070 single-step over breakpoints without removing them from the debuggee.
3071 Also known as "out-of-line single-stepping".
3074 show debug displaced
3075 Control display of debugging info for displaced stepping.
3077 maint set internal-error
3078 maint show internal-error
3079 Control what GDB does when an internal error is detected.
3081 maint set internal-warning
3082 maint show internal-warning
3083 Control what GDB does when an internal warning is detected.
3088 Use a wrapper program to launch programs for debugging.
3090 set multiple-symbols (all|ask|cancel)
3091 show multiple-symbols
3092 The value of this variable can be changed to adjust the debugger behavior
3093 when an expression or a breakpoint location contains an ambiguous symbol
3094 name (an overloaded function name, for instance).
3096 set breakpoint always-inserted
3097 show breakpoint always-inserted
3098 Keep breakpoints always inserted in the target, as opposed to inserting
3099 them when resuming the target, and removing them when the target stops.
3100 This option can improve debugger performance on slow remote targets.
3102 set arm fallback-mode (arm|thumb|auto)
3103 show arm fallback-mode
3104 set arm force-mode (arm|thumb|auto)
3106 These commands control how ARM GDB determines whether instructions
3107 are ARM or Thumb. The default for both settings is auto, which uses
3108 the current CPSR value for instructions without symbols; previous
3109 versions of GDB behaved as if "set arm fallback-mode arm".
3111 set disable-randomization
3112 show disable-randomization
3113 Standalone programs run with the virtual address space randomization enabled
3114 by default on some platforms. This option keeps the addresses stable across
3115 multiple debugging sessions.
3119 Control whether other threads are stopped or not when some thread hits
3124 Requests that asynchronous execution is enabled in the target, if available.
3125 In this case, it's possible to resume target in the background, and interact
3126 with GDB while the target is running. "show target-async" displays the
3127 current state of asynchronous execution of the target.
3129 set target-wide-charset
3130 show target-wide-charset
3131 The target-wide-charset is the name of the character set that GDB
3132 uses when printing characters whose type is wchar_t.
3134 set tcp auto-retry (on|off)
3136 set tcp connect-timeout
3137 show tcp connect-timeout
3138 These commands allow GDB to retry failed TCP connections to a remote stub
3139 with a specified timeout period; this is useful if the stub is launched
3140 in parallel with GDB but may not be ready to accept connections immediately.
3142 set libthread-db-search-path
3143 show libthread-db-search-path
3144 Control list of directories which GDB will search for appropriate
3147 set schedule-multiple (on|off)
3148 show schedule-multiple
3149 Allow GDB to resume all threads of all processes or only threads of
3150 the current process.
3154 Use more aggressive caching for accesses to the stack. This improves
3155 performance of remote debugging (particularly backtraces) without
3156 affecting correctness.
3158 set interactive-mode (on|off|auto)
3159 show interactive-mode
3160 Control whether GDB runs in interactive mode (on) or not (off).
3161 When in interactive mode, GDB waits for the user to answer all
3162 queries. Otherwise, GDB does not wait and assumes the default
3163 answer. When set to auto (the default), GDB determines which
3164 mode to use based on the stdin settings.
3169 For program forks, this is replaced by the new more generic `info
3170 inferiors' command. To list checkpoints, you can still use the
3171 `info checkpoints' command, which was an alias for the `info forks'
3175 Replaced by the new `inferior' command. To switch between
3176 checkpoints, you can still use the `restart' command, which was an
3177 alias for the `fork' command.
3180 This is removed, since some targets don't have a notion of
3181 processes. To switch between processes, you can still use the
3182 `inferior' command using GDB's own inferior number.
3185 For program forks, this is replaced by the new more generic `kill
3186 inferior' command. To delete a checkpoint, you can still use the
3187 `delete checkpoint' command, which was an alias for the `delete
3191 For program forks, this is replaced by the new more generic `detach
3192 inferior' command. To detach a checkpoint, you can still use the
3193 `detach checkpoint' command, which was an alias for the `detach
3196 * New native configurations
3198 x86/x86_64 Darwin i[34567]86-*-darwin*
3200 x86_64 MinGW x86_64-*-mingw*
3204 Lattice Mico32 lm32-*
3205 x86 DICOS i[34567]86-*-dicos*
3206 x86_64 DICOS x86_64-*-dicos*
3209 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3210 (mingw32ce) debugging.
3216 These commands were actually not implemented on any target.
3218 *** Changes in GDB 6.8
3220 * New native configurations
3222 NetBSD/hppa hppa*-*netbsd*
3223 Xtensa GNU/Linux xtensa*-*-linux*
3227 NetBSD/hppa hppa*-*-netbsd*
3228 Xtensa GNU/Lunux xtensa*-*-linux*
3230 * Change in command line behavior -- corefiles vs. process ids.
3232 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3233 attaching to process NUMBER fails, GDB no longer attempts to open a
3234 core file named NUMBER. Attaching to a program using the -c option
3235 is no longer supported. Instead, use the '-p' or '--pid' options.
3237 * GDB can now be built as a native debugger for debugging Windows x86
3238 (mingw32) Portable Executable (PE) programs.
3240 * Pending breakpoints no longer change their number when their address
3243 * GDB now supports breakpoints with multiple locations,
3244 including breakpoints on C++ constructors, inside C++ templates,
3245 and in inlined functions.
3247 * GDB's ability to debug optimized code has been improved. GDB more
3248 accurately identifies function bodies and lexical blocks that occupy
3249 more than one contiguous range of addresses.
3251 * Target descriptions can now describe registers for PowerPC.
3253 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3254 registers on PowerPC targets.
3256 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3257 targets even when the libthread_db library is not available.
3259 * The GDB remote stub, gdbserver, now supports the new file transfer
3260 commands (remote put, remote get, and remote delete).
3262 * The GDB remote stub, gdbserver, now supports run and attach in
3263 extended-remote mode.
3265 * hppa*64*-*-hpux11* target broken
3266 The debugger is unable to start a program and fails with the following
3267 error: "Error trying to get information about dynamic linker".
3268 The gdb-6.7 release is also affected.
3270 * GDB now supports the --enable-targets= configure option to allow
3271 building a single GDB executable that supports multiple remote
3272 target architectures.
3274 * GDB now supports debugging C and C++ programs which use the
3275 Decimal Floating Point extension. In addition, the PowerPC target
3276 now has a set of pseudo-registers to inspect decimal float values
3277 stored in two consecutive float registers.
3279 * The -break-insert MI command can optionally create pending
3282 * Improved support for debugging Ada
3283 Many improvements to the Ada language support have been made. These
3285 - Better support for Ada2005 interface types
3286 - Improved handling of arrays and slices in general
3287 - Better support for Taft-amendment types
3288 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3290 - Improved command completion in Ada
3293 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3298 set print frame-arguments (all|scalars|none)
3299 show print frame-arguments
3300 The value of this variable can be changed to control which argument
3301 values should be printed by the debugger when displaying a frame.
3306 Transfer files to and from a remote target, and delete remote files.
3313 Transfer files to and from a remote target, and delete remote files.
3315 * New remote packets
3322 Open, close, read, write, and delete files on the remote system.
3325 Attach to an existing process on the remote system, in extended-remote
3329 Run a new process on the remote system, in extended-remote mode.
3331 *** Changes in GDB 6.7
3333 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3334 bfd, libiberty and opcodes, as revealed by static analysis donated by
3335 Coverity, Inc. (http://scan.coverity.com).
3337 * When looking up multiply-defined global symbols, GDB will now prefer the
3338 symbol definition in the current shared library if it was built using the
3339 -Bsymbolic linker option.
3341 * When the Text User Interface (TUI) is not configured, GDB will now
3342 recognize the -tui command-line option and print a message that the TUI
3345 * The GDB remote stub, gdbserver, now has lower overhead for high
3346 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3348 * GDB for MIPS targets now autodetects whether a remote target provides
3349 32-bit or 64-bit register values.
3351 * Support for C++ member pointers has been improved.
3353 * GDB now understands XML target descriptions, which specify the
3354 target's overall architecture. GDB can read a description from
3355 a local file or over the remote serial protocol.
3357 * Vectors of single-byte data use a new integer type which is not
3358 automatically displayed as character or string data.
3360 * The /s format now works with the print command. It displays
3361 arrays of single-byte integers and pointers to single-byte integers
3364 * Target descriptions can now describe target-specific registers,
3365 for architectures which have implemented the support (currently
3366 only ARM, M68K, and MIPS).
3368 * GDB and the GDB remote stub, gdbserver, now support the XScale
3371 * The GDB remote stub, gdbserver, has been updated to support
3372 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3373 has been rewritten to use the standard GDB remote protocol.
3375 * GDB can now step into C++ functions which are called through thunks.
3377 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3379 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3380 layout. It also supports a TextSeg= and DataSeg= response when only
3381 segment base addresses (rather than offsets) are available.
3383 * The /i format now outputs any trailing branch delay slot instructions
3384 immediately following the last instruction within the count specified.
3386 * The GDB remote protocol "T" stop reply packet now supports a
3387 "library" response. Combined with the new "qXfer:libraries:read"
3388 packet, this response allows GDB to debug shared libraries on targets
3389 where the operating system manages the list of loaded libraries (e.g.
3390 Windows and SymbianOS).
3392 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3393 (DLLs) on Windows and Windows CE targets.
3395 * GDB now supports a faster verification that a .debug file matches its binary
3396 according to its build-id signature, if the signature is present.
3402 Enable or disable hardware flow control (RTS/CTS) on the serial port
3403 when debugging using remote targets.
3405 set mem inaccessible-by-default
3406 show mem inaccessible-by-default
3407 If the target supplies a memory map, for instance via the remote
3408 protocol's "qXfer:memory-map:read" packet, setting this variable
3409 prevents GDB from accessing memory outside the memory map. This
3410 is useful for targets with memory mapped registers or which react
3411 badly to accesses of unmapped address space.
3413 set breakpoint auto-hw
3414 show breakpoint auto-hw
3415 If the target supplies a memory map, for instance via the remote
3416 protocol's "qXfer:memory-map:read" packet, setting this variable
3417 lets GDB use hardware breakpoints automatically for memory regions
3418 where it can not use software breakpoints. This covers both the
3419 "break" command and internal breakpoints used for other commands
3420 including "next" and "finish".
3423 catch exception unhandled
3424 Stop the program execution when Ada exceptions are raised.
3427 Stop the program execution when an Ada assertion failed.
3431 Set an alternate system root for target files. This is a more
3432 general version of "set solib-absolute-prefix", which is now
3433 an alias to "set sysroot".
3436 Provide extended SPU facility status information. This set of
3437 commands is available only when debugging the Cell/B.E. SPU
3440 * New native configurations
3442 OpenBSD/sh sh*-*openbsd*
3445 unset tdesc filename
3447 Use the specified local file as an XML target description, and do
3448 not query the target for its built-in description.
3452 OpenBSD/sh sh*-*-openbsd*
3453 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3454 Toshiba Media Processor mep-elf
3456 * New remote packets
3459 Ignore the specified signals; pass them directly to the debugged program
3460 without stopping other threads or reporting them to GDB.
3462 qXfer:features:read:
3463 Read an XML target description from the target, which describes its
3468 Read or write contents of an spufs file on the target system. These
3469 packets are available only on the Cell/B.E. SPU architecture.
3471 qXfer:libraries:read:
3472 Report the loaded shared libraries. Combined with new "T" packet
3473 response, this packet allows GDB to debug shared libraries on
3474 targets where the operating system manages the list of loaded
3475 libraries (e.g. Windows and SymbianOS).
3479 Support for these obsolete configurations has been removed.
3487 i[34567]86-*-lynxos*
3488 i[34567]86-*-netware*
3489 i[34567]86-*-sco3.2v5*
3490 i[34567]86-*-sco3.2v4*
3492 i[34567]86-*-sysv4.2*
3495 i[34567]86-*-unixware2*
3496 i[34567]86-*-unixware*
3505 * Other removed features
3512 Various m68k-only ROM monitors.
3519 Various Renesas ROM monitors and debugging interfaces for SH and
3524 Support for a Macraigor serial interface to on-chip debugging.
3525 GDB does not directly support the newer parallel or USB
3530 A debug information format. The predecessor to DWARF 2 and
3531 DWARF 3, which are still supported.
3533 Support for the HP aCC compiler on HP-UX/PA-RISC
3535 SOM-encapsulated symbolic debugging information, automatic
3536 invocation of pxdb, and the aCC custom C++ ABI. This does not
3537 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3538 with aCC can still be debugged on an assembly level.
3540 MIPS ".pdr" sections
3542 A MIPS-specific format used to describe stack frame layout
3543 in debugging information.
3547 GDB could work with an older version of Guile to debug
3548 the interpreter and Scheme programs running in it.
3550 set mips stack-arg-size
3551 set mips saved-gpreg-size
3553 Use "set mips abi" to control parameter passing for MIPS.
3555 *** Changes in GDB 6.6
3560 Cell Broadband Engine SPU spu-elf
3562 * GDB can now be configured as a cross-debugger targeting native Windows
3563 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3564 running on a Windows system over TCP/IP to debug Windows programs.
3566 * The GDB remote stub, gdbserver, has been updated to support Windows and
3567 Cygwin debugging. Both single-threaded and multi-threaded programs are
3570 * The "set trust-readonly-sections" command works again. This command was
3571 broken in GDB 6.3, 6.4, and 6.5.
3573 * The "load" command now supports writing to flash memory, if the remote
3574 stub provides the required support.
3576 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3577 longer requires symbolic debug information (e.g. DWARF-2).
3582 unset substitute-path
3583 show substitute-path
3584 Manage a list of substitution rules that GDB uses to rewrite the name
3585 of the directories where the sources are located. This can be useful
3586 for instance when the sources were moved to a different location
3587 between compilation and debugging.
3591 Print each CLI command as it is executed. Each command is prefixed with
3592 a number of `+' symbols representing the nesting depth.
3593 The source command now has a `-v' option to enable the same feature.
3597 The ARM Demon monitor support (RDP protocol, "target rdp").
3599 Kernel Object Display, an embedded debugging feature which only worked with
3600 an obsolete version of Cisco IOS.
3602 The 'set download-write-size' and 'show download-write-size' commands.
3604 * New remote packets
3607 Tell a stub about GDB client features, and request remote target features.
3608 The first feature implemented is PacketSize, which allows the target to
3609 specify the size of packets it can handle - to minimize the number of
3610 packets required and improve performance when connected to a remote
3614 Fetch an OS auxilliary vector from the remote stub. This packet is a
3615 more efficient replacement for qPart:auxv:read.
3617 qXfer:memory-map:read:
3618 Fetch a memory map from the remote stub, including information about
3619 RAM, ROM, and flash memory devices.
3624 Erase and program a flash memory device.
3626 * Removed remote packets
3629 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3630 used it, and only gdbserver implemented it.
3632 *** Changes in GDB 6.5
3636 Renesas M32C/M16C m32c-elf
3638 Morpho Technologies ms1 ms1-elf
3642 init-if-undefined Initialize a convenience variable, but
3643 only if it doesn't already have a value.
3645 The following commands are presently only implemented for native GNU/Linux:
3647 checkpoint Save a snapshot of the program state.
3649 restart <n> Return the program state to a
3650 previously saved state.
3652 info checkpoints List currently saved checkpoints.
3654 delete-checkpoint <n> Delete a previously saved checkpoint.
3656 set|show detach-on-fork Tell gdb whether to detach from a newly
3657 forked process, or to keep debugging it.
3659 info forks List forks of the user program that
3660 are available to be debugged.
3662 fork <n> Switch to debugging one of several
3663 forks of the user program that are
3664 available to be debugged.
3666 delete-fork <n> Delete a fork from the list of forks
3667 that are available to be debugged (and
3668 kill the forked process).
3670 detach-fork <n> Delete a fork from the list of forks
3671 that are available to be debugged (and
3672 allow the process to continue).
3676 Morpho Technologies ms2 ms1-elf
3678 * Improved Windows host support
3680 GDB now builds as a cross debugger hosted on i686-mingw32, including
3681 native console support, and remote communications using either
3682 network sockets or serial ports.
3684 * Improved Modula-2 language support
3686 GDB can now print most types in the Modula-2 syntax. This includes:
3687 basic types, set types, record types, enumerated types, range types,
3688 pointer types and ARRAY types. Procedure var parameters are correctly
3689 printed and hexadecimal addresses and character constants are also
3690 written in the Modula-2 syntax. Best results can be obtained by using
3691 GNU Modula-2 together with the -gdwarf-2 command line option.
3695 The ARM rdi-share module.
3697 The Netware NLM debug server.
3699 *** Changes in GDB 6.4
3701 * New native configurations
3703 OpenBSD/arm arm*-*-openbsd*
3704 OpenBSD/mips64 mips64-*-openbsd*
3708 Morpho Technologies ms1 ms1-elf
3710 * New command line options
3712 --batch-silent As for --batch, but totally silent.
3713 --return-child-result The debugger will exist with the same value
3714 the child (debugged) program exited with.
3715 --eval-command COMMAND, -ex COMMAND
3716 Execute a single GDB CLI command. This may be
3717 specified multiple times and in conjunction
3718 with the --command (-x) option.
3720 * Deprecated commands removed
3722 The following commands, that were deprecated in 2000, have been
3726 set|show arm disassembly-flavor set|show arm disassembler
3727 othernames set arm disassembler
3728 set|show remotedebug set|show debug remote
3729 set|show archdebug set|show debug arch
3730 set|show eventdebug set|show debug event
3733 * New BSD user-level threads support
3735 It is now possible to debug programs using the user-level threads
3736 library on OpenBSD and FreeBSD. Currently supported (target)
3739 FreeBSD/amd64 x86_64-*-freebsd*
3740 FreeBSD/i386 i386-*-freebsd*
3741 OpenBSD/i386 i386-*-openbsd*
3743 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3744 are not yet supported.
3746 * New support for Matsushita MN10300 w/sim added
3747 (Work in progress). mn10300-elf.
3749 * REMOVED configurations and files
3751 VxWorks and the XDR protocol *-*-vxworks
3752 Motorola MCORE mcore-*-*
3753 National Semiconductor NS32000 ns32k-*-*
3755 * New "set print array-indexes" command
3757 After turning this setting "on", GDB prints the index of each element
3758 when displaying arrays. The default is "off" to preserve the previous
3761 * VAX floating point support
3763 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3765 * User-defined command support
3767 In addition to using $arg0..$arg9 for argument passing, it is now possible
3768 to use $argc to determine now many arguments have been passed. See the
3769 section on user-defined commands in the user manual for more information.
3771 *** Changes in GDB 6.3:
3773 * New command line option
3775 GDB now accepts -l followed by a number to set the timeout for remote
3778 * GDB works with GCC -feliminate-dwarf2-dups
3780 GDB now supports a more compact representation of DWARF-2 debug
3781 information using DW_FORM_ref_addr references. These are produced
3782 by GCC with the option -feliminate-dwarf2-dups and also by some
3783 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3784 to use -feliminate-dwarf2-dups.
3786 * Internationalization
3788 When supported by the host system, GDB will be built with
3789 internationalization (libintl). The task of marking up the sources is
3790 continued, we're looking forward to our first translation.
3794 Initial support for debugging programs compiled with the GNAT
3795 implementation of the Ada programming language has been integrated
3796 into GDB. In this release, support is limited to expression evaluation.
3798 * New native configurations
3800 GNU/Linux/m32r m32r-*-linux-gnu
3804 GDB's remote protocol now includes support for the 'p' packet. This
3805 packet is used to fetch individual registers from a remote inferior.
3807 * END-OF-LIFE registers[] compatibility module
3809 GDB's internal register infrastructure has been completely rewritten.
3810 The new infrastructure making possible the implementation of key new
3811 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3814 GDB 6.3 will be the last release to include the the registers[]
3815 compatibility module that allowed out-of-date configurations to
3816 continue to work. This change directly impacts the following
3826 powerpc bdm protocol
3828 Unless there is activity to revive these configurations, they will be
3829 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3831 * OBSOLETE configurations and files
3833 Configurations that have been declared obsolete in this release have
3834 been commented out. Unless there is activity to revive these
3835 configurations, the next release of GDB will have their sources
3836 permanently REMOVED.
3845 *** Changes in GDB 6.2.1:
3847 * MIPS `break main; run' gave an heuristic-fence-post warning
3849 When attempting to run even a simple program, a warning about
3850 heuristic-fence-post being hit would be reported. This problem has
3853 * MIPS IRIX 'long double' crashed GDB
3855 When examining a long double variable, GDB would get a segmentation
3856 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3857 IRIX long double values).
3861 A bug in the VAX stack code was causing problems with the "next"
3862 command. This problem has been fixed.
3864 *** Changes in GDB 6.2:
3866 * Fix for ``many threads''
3868 On GNU/Linux systems that use the NPTL threads library, a program
3869 rapidly creating and deleting threads would confuse GDB leading to the
3872 ptrace: No such process.
3873 thread_db_get_info: cannot get thread info: generic error
3875 This problem has been fixed.
3877 * "-async" and "-noasync" options removed.
3879 Support for the broken "-noasync" option has been removed (it caused
3882 * New ``start'' command.
3884 This command runs the program until the begining of the main procedure.
3886 * New BSD Kernel Data Access Library (libkvm) interface
3888 Using ``target kvm'' it is now possible to debug kernel core dumps and
3889 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3890 platforms. Currently supported (native-only) configurations are:
3892 FreeBSD/amd64 x86_64-*-freebsd*
3893 FreeBSD/i386 i?86-*-freebsd*
3894 NetBSD/i386 i?86-*-netbsd*
3895 NetBSD/m68k m68*-*-netbsd*
3896 NetBSD/sparc sparc-*-netbsd*
3897 OpenBSD/amd64 x86_64-*-openbsd*
3898 OpenBSD/i386 i?86-*-openbsd*
3899 OpenBSD/m68k m68*-openbsd*
3900 OpenBSD/sparc sparc-*-openbsd*
3902 * Signal trampoline code overhauled
3904 Many generic problems with GDB's signal handling code have been fixed.
3905 These include: backtraces through non-contiguous stacks; recognition
3906 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3907 call; backtrace through a signal trampoline; step into and out of
3908 signal handlers; and single-stepping in the signal trampoline.
3910 Please note that kernel bugs are a limiting factor here. These
3911 features have been shown to work on an s390 GNU/Linux system that
3912 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3914 * Cygwin support for DWARF 2 added.
3916 * New native configurations
3918 GNU/Linux/hppa hppa*-*-linux*
3919 OpenBSD/hppa hppa*-*-openbsd*
3920 OpenBSD/m68k m68*-*-openbsd*
3921 OpenBSD/m88k m88*-*-openbsd*
3922 OpenBSD/powerpc powerpc-*-openbsd*
3923 NetBSD/vax vax-*-netbsd*
3924 OpenBSD/vax vax-*-openbsd*
3926 * END-OF-LIFE frame compatibility module
3928 GDB's internal frame infrastructure has been completely rewritten.
3929 The new infrastructure making it possible to support key new features
3930 including DWARF 2 Call Frame Information. To aid in the task of
3931 migrating old configurations to this new infrastructure, a
3932 compatibility module, that allowed old configurations to continue to
3933 work, was also included.
3935 GDB 6.2 will be the last release to include this frame compatibility
3936 module. This change directly impacts the following configurations:
3946 Unless there is activity to revive these configurations, they will be
3947 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3949 * REMOVED configurations and files
3951 Sun 3, running SunOS 3 m68*-*-sunos3*
3952 Sun 3, running SunOS 4 m68*-*-sunos4*
3953 Sun 2, running SunOS 3 m68000-*-sunos3*
3954 Sun 2, running SunOS 4 m68000-*-sunos4*
3955 Motorola 680x0 running LynxOS m68*-*-lynxos*
3956 AT&T 3b1/Unix pc m68*-att-*
3957 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3958 decstation mips-dec-* mips-little-*
3959 riscos mips-*-riscos* mips-*-sysv*
3960 sonymips mips-sony-*
3961 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3963 *** Changes in GDB 6.1.1:
3965 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3967 The TUI (Text-mode User Interface) is now built as part of a default
3968 GDB configuration. It is enabled by either selecting the TUI with the
3969 command line option "-i=tui" or by running the separate "gdbtui"
3970 program. For more information on the TUI, see the manual "Debugging
3973 * Pending breakpoint support (also included in GDB 6.1)
3975 Support has been added to allow you to specify breakpoints in shared
3976 libraries that have not yet been loaded. If a breakpoint location
3977 cannot be found, and the "breakpoint pending" option is set to auto,
3978 GDB queries you if you wish to make the breakpoint pending on a future
3979 shared-library load. If and when GDB resolves the breakpoint symbol,
3980 the pending breakpoint is removed as one or more regular breakpoints
3983 Pending breakpoints are very useful for GCJ Java debugging.
3985 * Fixed ISO-C build problems
3987 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3988 non ISO-C code that stopped them being built using a more strict ISO-C
3989 compiler (e.g., IBM's C compiler).
3991 * Fixed build problem on IRIX 5
3993 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3994 wasn't able to compile compile on an IRIX 5 system.
3996 * Added execute permission to gdb/gdbserver/configure
3998 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3999 permission. This bug would cause configure to fail on a number of
4000 systems (Solaris, IRIX). Ref: server/519.
4002 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4004 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4005 has been updated to use constant array sizes.
4007 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4009 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4010 its generated DWARF Call Frame Info. This encoding was causing GDB to
4011 panic, that panic has been fixed. Ref: gdb/1628.
4013 * Fixed a problem when examining parameters in shared library code.
4015 When examining parameters in optimized shared library code generated
4016 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4017 not available''. GDB now correctly displays the variable's value.
4019 *** Changes in GDB 6.1:
4021 * Removed --with-mmalloc
4023 Support for the mmalloc memory manager has been removed, as it
4024 conflicted with the internal gdb byte cache.
4026 * Changes in AMD64 configurations
4028 The AMD64 target now includes the %cs and %ss registers. As a result
4029 the AMD64 remote protocol has changed; this affects the floating-point
4030 and SSE registers. If you rely on those registers for your debugging,
4031 you should upgrade gdbserver on the remote side.
4033 * Revised SPARC target
4035 The SPARC target has been completely revised, incorporating the
4036 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4037 support for LynxOS and SunOS 4 has been dropped. Calling functions
4038 from within GDB on operating systems with a non-executable stack
4039 (Solaris, OpenBSD) now works.
4043 GDB has a new C++ demangler which does a better job on the mangled
4044 names generated by current versions of g++. It also runs faster, so
4045 with this and other changes gdb should now start faster on large C++
4048 * DWARF 2 Location Expressions
4050 GDB support for location expressions has been extended to support function
4051 arguments and frame bases. Older versions of GDB could crash when they
4054 * C++ nested types and namespaces
4056 GDB's support for nested types and namespaces in C++ has been
4057 improved, especially if you use the DWARF 2 debugging format. (This
4058 is the default for recent versions of GCC on most platforms.)
4059 Specifically, if you have a class "Inner" defined within a class or
4060 namespace "Outer", then GDB realizes that the class's name is
4061 "Outer::Inner", not simply "Inner". This should greatly reduce the
4062 frequency of complaints about not finding RTTI symbols. In addition,
4063 if you are stopped at inside of a function defined within a namespace,
4064 GDB modifies its name lookup accordingly.
4066 * New native configurations
4068 NetBSD/amd64 x86_64-*-netbsd*
4069 OpenBSD/amd64 x86_64-*-openbsd*
4070 OpenBSD/alpha alpha*-*-openbsd*
4071 OpenBSD/sparc sparc-*-openbsd*
4072 OpenBSD/sparc64 sparc64-*-openbsd*
4074 * New debugging protocols
4076 M32R with SDI protocol m32r-*-elf*
4078 * "set prompt-escape-char" command deleted.
4080 The command "set prompt-escape-char" has been deleted. This command,
4081 and its very obscure effet on GDB's prompt, was never documented,
4082 tested, nor mentioned in the NEWS file.
4084 * OBSOLETE configurations and files
4086 Configurations that have been declared obsolete in this release have
4087 been commented out. Unless there is activity to revive these
4088 configurations, the next release of GDB will have their sources
4089 permanently REMOVED.
4091 Sun 3, running SunOS 3 m68*-*-sunos3*
4092 Sun 3, running SunOS 4 m68*-*-sunos4*
4093 Sun 2, running SunOS 3 m68000-*-sunos3*
4094 Sun 2, running SunOS 4 m68000-*-sunos4*
4095 Motorola 680x0 running LynxOS m68*-*-lynxos*
4096 AT&T 3b1/Unix pc m68*-att-*
4097 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4098 decstation mips-dec-* mips-little-*
4099 riscos mips-*-riscos* mips-*-sysv*
4100 sonymips mips-sony-*
4101 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4103 * REMOVED configurations and files
4105 SGI Irix-4.x mips-sgi-irix4 or iris4
4106 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4107 Z8000 simulator z8k-zilog-none or z8ksim
4108 Matsushita MN10200 w/simulator mn10200-*-*
4109 H8/500 simulator h8500-hitachi-hms or h8500hms
4110 HP/PA running BSD hppa*-*-bsd*
4111 HP/PA running OSF/1 hppa*-*-osf*
4112 HP/PA Pro target hppa*-*-pro*
4113 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4114 386BSD i[3456]86-*-bsd*
4115 Sequent family i[3456]86-sequent-sysv4*
4116 i[3456]86-sequent-sysv*
4117 i[3456]86-sequent-bsd*
4118 SPARC running LynxOS sparc-*-lynxos*
4119 SPARC running SunOS 4 sparc-*-sunos4*
4120 Tsqware Sparclet sparclet-*-*
4121 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4123 *** Changes in GDB 6.0:
4127 Support for debugging the Objective-C programming language has been
4128 integrated into GDB.
4130 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4132 DWARF 2's Call Frame Information makes available compiler generated
4133 information that more exactly describes the program's run-time stack.
4134 By using this information, GDB is able to provide more robust stack
4137 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4138 have been updated to use a new backtrace mechanism which includes
4139 DWARF 2 CFI support.
4143 GDB's remote protocol has been extended to include support for hosted
4144 file I/O (where the remote target uses GDB's file system). See GDB's
4145 remote protocol documentation for details.
4147 * All targets using the new architecture framework.
4149 All of GDB's targets have been updated to use the new internal
4150 architecture framework. The way is now open for future GDB releases
4151 to include cross-architecture native debugging support (i386 on amd64,
4154 * GNU/Linux's Thread Local Storage (TLS)
4156 GDB now includes support for for the GNU/Linux implementation of
4157 per-thread variables.
4159 * GNU/Linux's Native POSIX Thread Library (NPTL)
4161 GDB's thread code has been updated to work with either the new
4162 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4164 * Separate debug info.
4166 GDB, in conjunction with BINUTILS, now supports a mechanism for
4167 automatically loading debug information from a separate file. Instead
4168 of shipping full debug and non-debug versions of system libraries,
4169 system integrators can now instead ship just the stripped libraries
4170 and optional debug files.
4172 * DWARF 2 Location Expressions
4174 DWARF 2 Location Expressions allow the compiler to more completely
4175 describe the location of variables (even in optimized code) to the
4178 GDB now includes preliminary support for location expressions (support
4179 for DW_OP_piece is still missing).
4183 A number of long standing bugs that caused GDB to die while starting a
4184 Java application have been fixed. GDB's Java support is now
4185 considered "useable".
4187 * GNU/Linux support for fork, vfork, and exec.
4189 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4190 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4193 * GDB supports logging output to a file
4195 There are two new commands, "set logging" and "show logging", which can be
4196 used to capture GDB's output to a file.
4198 * The meaning of "detach" has changed for gdbserver
4200 The "detach" command will now resume the application, as documented. To
4201 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4204 * d10v, m68hc11 `regs' command deprecated
4206 The `info registers' command has been updated so that it displays the
4207 registers using a format identical to the old `regs' command.
4211 A new command, "maint set profile on/off", has been added. This command can
4212 be used to enable or disable profiling while running GDB, to profile a
4213 session or a set of commands. In addition there is a new configure switch,
4214 "--enable-profiling", which will cause GDB to be compiled with profiling
4215 data, for more informative profiling results.
4217 * Default MI syntax changed to "mi2".
4219 The default MI (machine interface) syntax, enabled by the command line
4220 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4221 "mi1", can be enabled by specifying the option "-i=mi1".
4223 Support for the original "mi0" syntax (included in GDB 5.0) has been
4226 Fix for gdb/192: removed extraneous space when displaying frame level.
4227 Fix for gdb/672: update changelist is now output in mi list format.
4228 Fix for gdb/702: a -var-assign that updates the value now shows up
4229 in a subsequent -var-update.
4231 * New native configurations.
4233 FreeBSD/amd64 x86_64-*-freebsd*
4235 * Multi-arched targets.
4237 HP/PA HPUX11 hppa*-*-hpux*
4238 Renesas M32R/D w/simulator m32r-*-elf*
4240 * OBSOLETE configurations and files
4242 Configurations that have been declared obsolete in this release have
4243 been commented out. Unless there is activity to revive these
4244 configurations, the next release of GDB will have their sources
4245 permanently REMOVED.
4247 Z8000 simulator z8k-zilog-none or z8ksim
4248 Matsushita MN10200 w/simulator mn10200-*-*
4249 H8/500 simulator h8500-hitachi-hms or h8500hms
4250 HP/PA running BSD hppa*-*-bsd*
4251 HP/PA running OSF/1 hppa*-*-osf*
4252 HP/PA Pro target hppa*-*-pro*
4253 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4254 Sequent family i[3456]86-sequent-sysv4*
4255 i[3456]86-sequent-sysv*
4256 i[3456]86-sequent-bsd*
4257 Tsqware Sparclet sparclet-*-*
4258 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4260 * REMOVED configurations and files
4263 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4264 IBM AIX PS/2 i[3456]86-*-aix
4265 i386 running Mach 3.0 i[3456]86-*-mach3*
4266 i386 running Mach i[3456]86-*-mach*
4267 i386 running OSF/1 i[3456]86-*osf1mk*
4268 HP/Apollo 68k Family m68*-apollo*-sysv*,
4270 m68*-hp-bsd*, m68*-hp-hpux*
4271 Argonaut Risc Chip (ARC) arc-*-*
4272 Mitsubishi D30V d30v-*-*
4273 Fujitsu FR30 fr30-*-elf*
4274 OS/9000 i[34]86-*-os9k
4275 I960 with MON960 i960-*-coff
4277 * MIPS $fp behavior changed
4279 The convenience variable $fp, for the MIPS, now consistently returns
4280 the address of the current frame's base. Previously, depending on the
4281 context, $fp could refer to either $sp or the current frame's base
4282 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4283 The GNU Source-Level Debugger''.
4285 *** Changes in GDB 5.3:
4287 * GNU/Linux shared library multi-threaded performance improved.
4289 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4290 `/proc', in preference to `ptrace' for memory reads. This may result
4291 in an improvement in the start-up time of multi-threaded, shared
4292 library applications when run under GDB. One GDB user writes: ``loads
4293 shared libs like mad''.
4295 * ``gdbserver'' now supports multi-threaded applications on some targets
4297 Support for debugging multi-threaded applications which use
4298 the GNU/Linux LinuxThreads package has been added for
4299 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4300 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4302 * GDB now supports C/C++ preprocessor macros.
4304 GDB now expands preprocessor macro invocations in C/C++ expressions,
4305 and provides various commands for showing macro definitions and how
4308 The new command `macro expand EXPRESSION' expands any macro
4309 invocations in expression, and shows the result.
4311 The new command `show macro MACRO-NAME' shows the definition of the
4312 macro named MACRO-NAME, and where it was defined.
4314 Most compilers don't include information about macros in the debugging
4315 information by default. In GCC 3.1, for example, you need to compile
4316 your program with the options `-gdwarf-2 -g3'. If the macro
4317 information is present in the executable, GDB will read it.
4319 * Multi-arched targets.
4321 DEC Alpha (partial) alpha*-*-*
4322 DEC VAX (partial) vax-*-*
4324 National Semiconductor NS32000 (partial) ns32k-*-*
4325 Motorola 68000 (partial) m68k-*-*
4326 Motorola MCORE mcore-*-*
4330 Fujitsu FRV architecture added by Red Hat frv*-*-*
4333 * New native configurations
4335 Alpha NetBSD alpha*-*-netbsd*
4336 SH NetBSD sh*-*-netbsdelf*
4337 MIPS NetBSD mips*-*-netbsd*
4338 UltraSPARC NetBSD sparc64-*-netbsd*
4340 * OBSOLETE configurations and files
4342 Configurations that have been declared obsolete in this release have
4343 been commented out. Unless there is activity to revive these
4344 configurations, the next release of GDB will have their sources
4345 permanently REMOVED.
4347 Mitsubishi D30V d30v-*-*
4348 OS/9000 i[34]86-*-os9k
4349 IBM AIX PS/2 i[3456]86-*-aix
4350 Fujitsu FR30 fr30-*-elf*
4351 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4352 Argonaut Risc Chip (ARC) arc-*-*
4353 i386 running Mach 3.0 i[3456]86-*-mach3*
4354 i386 running Mach i[3456]86-*-mach*
4355 i386 running OSF/1 i[3456]86-*osf1mk*
4356 HP/Apollo 68k Family m68*-apollo*-sysv*,
4358 m68*-hp-bsd*, m68*-hp-hpux*
4359 I960 with MON960 i960-*-coff
4361 * OBSOLETE languages
4363 CHILL, a Pascal like language used by telecommunications companies.
4365 * REMOVED configurations and files
4367 AMD 29k family via UDI a29k-amd-udi, udi29k
4368 A29K VxWorks a29k-*-vxworks
4369 AMD 29000 embedded, using EBMON a29k-none-none
4370 AMD 29000 embedded with COFF a29k-none-coff
4371 AMD 29000 embedded with a.out a29k-none-aout
4373 testsuite/gdb.hp/gdb.threads-hp/ directory
4375 * New command "set max-user-call-depth <nnn>"
4377 This command allows the user to limit the call depth of user-defined
4378 commands. The default is 1024.
4380 * Changes in FreeBSD/i386 native debugging.
4382 Support for the "generate-core-file" has been added.
4384 * New commands "dump", "append", and "restore".
4386 These commands allow data to be copied from target memory
4387 to a bfd-format or binary file (dump and append), and back
4388 from a file into memory (restore).
4390 * Improved "next/step" support on multi-processor Alpha Tru64.
4392 The previous single-step mechanism could cause unpredictable problems,
4393 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4394 of a software single-step mechanism prevents this.
4396 *** Changes in GDB 5.2.1:
4404 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4405 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4406 Fix, by Joel Brobecker imported from mainline.
4408 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4409 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4410 Fix, by Fred Fish, imported from mainline.
4412 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4413 Surprisingly enough, it works now.
4414 By Michal Ludvig, imported from mainline.
4416 i386 hardware watchpoint support:
4417 avoid misses on second run for some targets.
4418 By Pierre Muller, imported from mainline.
4420 *** Changes in GDB 5.2:
4422 * New command "set trust-readonly-sections on[off]".
4424 This command is a hint that tells gdb that read-only sections
4425 really are read-only (ie. that their contents will not change).
4426 In this mode, gdb will go to the object file rather than the
4427 target to read memory from read-only sections (such as ".text").
4428 This can be a significant performance improvement on some
4429 (notably embedded) targets.
4431 * New command "generate-core-file" (or "gcore").
4433 This new gdb command allows the user to drop a core file of the child
4434 process state at any time. So far it's been implemented only for
4435 GNU/Linux and Solaris, but should be relatively easily ported to other
4436 hosts. Argument is core file name (defaults to core.<pid>).
4438 * New command line option
4440 GDB now accepts --pid or -p followed by a process id.
4442 * Change in command line behavior -- corefiles vs. process ids.
4444 There is a subtle behavior in the way in which GDB handles
4445 command line arguments. The first non-flag argument is always
4446 a program to debug, but the second non-flag argument may either
4447 be a corefile or a process id. Previously, GDB would attempt to
4448 open the second argument as a corefile, and if that failed, would
4449 issue a superfluous error message and then attempt to attach it as
4450 a process. Now, if the second argument begins with a non-digit,
4451 it will be treated as a corefile. If it begins with a digit,
4452 GDB will attempt to attach it as a process, and if no such process
4453 is found, will then attempt to open it as a corefile.
4455 * Changes in ARM configurations.
4457 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4458 configuration is fully multi-arch.
4460 * New native configurations
4462 ARM NetBSD arm*-*-netbsd*
4463 x86 OpenBSD i[3456]86-*-openbsd*
4464 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4465 Sparc64 running FreeBSD sparc64-*-freebsd*
4469 Sanyo XStormy16 xstormy16-elf
4471 * OBSOLETE configurations and files
4473 Configurations that have been declared obsolete in this release have
4474 been commented out. Unless there is activity to revive these
4475 configurations, the next release of GDB will have their sources
4476 permanently REMOVED.
4478 AMD 29k family via UDI a29k-amd-udi, udi29k
4479 A29K VxWorks a29k-*-vxworks
4480 AMD 29000 embedded, using EBMON a29k-none-none
4481 AMD 29000 embedded with COFF a29k-none-coff
4482 AMD 29000 embedded with a.out a29k-none-aout
4484 testsuite/gdb.hp/gdb.threads-hp/ directory
4486 * REMOVED configurations and files
4488 TI TMS320C80 tic80-*-*
4490 PowerPC Solaris powerpcle-*-solaris*
4491 PowerPC Windows NT powerpcle-*-cygwin32
4492 PowerPC Netware powerpc-*-netware*
4493 Harris/CXUX m88k m88*-harris-cxux*
4494 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4495 ns32k-utek-sysv* ns32k-utek-*
4496 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4497 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4498 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4499 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4500 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4502 * Changes to command line processing
4504 The new `--args' feature can be used to specify command-line arguments
4505 for the inferior from gdb's command line.
4507 * Changes to key bindings
4509 There is a new `operate-and-get-next' function bound to `C-o'.
4511 *** Changes in GDB 5.1.1
4513 Fix compile problem on DJGPP.
4515 Fix a problem with floating-point registers on the i386 being
4518 Fix to stop GDB crashing on .debug_str debug info.
4520 Numerous documentation fixes.
4522 Numerous testsuite fixes.
4524 *** Changes in GDB 5.1:
4526 * New native configurations
4528 Alpha FreeBSD alpha*-*-freebsd*
4529 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4530 MIPS GNU/Linux mips*-*-linux*
4531 MIPS SGI Irix 6.x mips*-sgi-irix6*
4532 ia64 AIX ia64-*-aix*
4533 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4537 Motorola 68HC11 and 68HC12 m68hc11-elf
4539 UltraSparc running GNU/Linux sparc64-*-linux*
4541 * OBSOLETE configurations and files
4543 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4544 Harris/CXUX m88k m88*-harris-cxux*
4545 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4546 ns32k-utek-sysv* ns32k-utek-*
4547 TI TMS320C80 tic80-*-*
4549 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4550 PowerPC Solaris powerpcle-*-solaris*
4551 PowerPC Windows NT powerpcle-*-cygwin32
4552 PowerPC Netware powerpc-*-netware*
4553 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4554 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4555 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4556 Apple Macintosh (MPW) host N/A
4558 stuff.c (Program to stuff files into a specially prepared space in kdb)
4559 kdb-start.c (Main loop for the standalone kernel debugger)
4561 Configurations that have been declared obsolete in this release have
4562 been commented out. Unless there is activity to revive these
4563 configurations, the next release of GDB will have their sources
4564 permanently REMOVED.
4566 * REMOVED configurations and files
4568 Altos 3068 m68*-altos-*
4569 Convex c1-*-*, c2-*-*
4571 ARM RISCix arm-*-* (as host)
4575 * GDB has been converted to ISO C.
4577 GDB's source code has been converted to ISO C. In particular, the
4578 sources are fully protoized, and rely on standard headers being
4583 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4585 * The MI enabled by default.
4587 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4588 revised and enabled by default. Packages which use GDB as a debugging
4589 engine behind a UI or another front end are encouraged to switch to
4590 using the GDB/MI interface, instead of the old annotations interface
4591 which is now deprecated.
4593 * Support for debugging Pascal programs.
4595 GDB now includes support for debugging Pascal programs. The following
4596 main features are supported:
4598 - Pascal-specific data types such as sets;
4600 - automatic recognition of Pascal sources based on file-name
4603 - Pascal-style display of data types, variables, and functions;
4605 - a Pascal expression parser.
4607 However, some important features are not yet supported.
4609 - Pascal string operations are not supported at all;
4611 - there are some problems with boolean types;
4613 - Pascal type hexadecimal constants are not supported
4614 because they conflict with the internal variables format;
4616 - support for Pascal objects and classes is not full yet;
4618 - unlike Pascal, GDB is case-sensitive for symbol names.
4620 * Changes in completion.
4622 Commands such as `shell', `run' and `set args', which pass arguments
4623 to inferior programs, now complete on file names, similar to what
4624 users expect at the shell prompt.
4626 Commands which accept locations, such as `disassemble', `print',
4627 `breakpoint', `until', etc. now complete on filenames as well as
4628 program symbols. Thus, if you type "break foob TAB", and the source
4629 files linked into the programs include `foobar.c', that file name will
4630 be one of the candidates for completion. However, file names are not
4631 considered for completion after you typed a colon that delimits a file
4632 name from a name of a function in that file, as in "break foo.c:bar".
4634 `set demangle-style' completes on available demangling styles.
4636 * New platform-independent commands:
4638 It is now possible to define a post-hook for a command as well as a
4639 hook that runs before the command. For more details, see the
4640 documentation of `hookpost' in the GDB manual.
4642 * Changes in GNU/Linux native debugging.
4644 Support for debugging multi-threaded programs has been completely
4645 revised for all platforms except m68k and sparc. You can now debug as
4646 many threads as your system allows you to have.
4648 Attach/detach is supported for multi-threaded programs.
4650 Support for SSE registers was added for x86. This doesn't work for
4651 multi-threaded programs though.
4653 * Changes in MIPS configurations.
4655 Multi-arch support is enabled for all MIPS configurations.
4657 GDB can now be built as native debugger on SGI Irix 6.x systems for
4658 debugging n32 executables. (Debugging 64-bit executables is not yet
4661 * Unified support for hardware watchpoints in all x86 configurations.
4663 Most (if not all) native x86 configurations support hardware-assisted
4664 breakpoints and watchpoints in a unified manner. This support
4665 implements debug register sharing between watchpoints, which allows to
4666 put a virtually infinite number of watchpoints on the same address,
4667 and also supports watching regions up to 16 bytes with several debug
4670 The new maintenance command `maintenance show-debug-regs' toggles
4671 debugging print-outs in functions that insert, remove, and test
4672 watchpoints and hardware breakpoints.
4674 * Changes in the DJGPP native configuration.
4676 New command ``info dos sysinfo'' displays assorted information about
4677 the CPU, OS, memory, and DPMI server.
4679 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4680 display information about segment descriptors stored in GDT, LDT, and
4683 New commands ``info dos pde'' and ``info dos pte'' display entries
4684 from Page Directory and Page Tables (for now works with CWSDPMI only).
4685 New command ``info dos address-pte'' displays the Page Table entry for
4686 a given linear address.
4688 GDB can now pass command lines longer than 126 characters to the
4689 program being debugged (requires an update to the libdbg.a library
4690 which is part of the DJGPP development kit).
4692 DWARF2 debug info is now supported.
4694 It is now possible to `step' and `next' through calls to `longjmp'.
4696 * Changes in documentation.
4698 All GDB documentation was converted to GFDL, the GNU Free
4699 Documentation License.
4701 Tracepoints-related commands are now fully documented in the GDB
4704 TUI, the Text-mode User Interface, is now documented in the manual.
4706 Tracepoints-related commands are now fully documented in the GDB
4709 The "GDB Internals" manual now has an index. It also includes
4710 documentation of `ui_out' functions, GDB coding standards, x86
4711 hardware watchpoints, and memory region attributes.
4713 * GDB's version number moved to ``version.in''
4715 The Makefile variable VERSION has been replaced by the file
4716 ``version.in''. People creating GDB distributions should update the
4717 contents of this file.
4721 GUD support is now a standard part of the EMACS distribution.
4723 *** Changes in GDB 5.0:
4725 * Improved support for debugging FP programs on x86 targets
4727 Unified and much-improved support for debugging floating-point
4728 programs on all x86 targets. In particular, ``info float'' now
4729 displays the FP registers in the same format on all x86 targets, with
4730 greater level of detail.
4732 * Improvements and bugfixes in hardware-assisted watchpoints
4734 It is now possible to watch array elements, struct members, and
4735 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4736 on x86 targets no longer erroneously trigger when the address is
4739 * Improvements in the native DJGPP version of GDB
4741 The distribution now includes all the scripts and auxiliary files
4742 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4743 machines ``out of the box''.
4745 The DJGPP version can now debug programs that use signals. It is
4746 possible to catch signals that happened in the debuggee, deliver
4747 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4748 would kill the program being debugged.) Programs that hook hardware
4749 interrupts (keyboard, timer, etc.) can also be debugged.
4751 It is now possible to debug DJGPP programs that redirect their
4752 standard handles or switch them to raw (as opposed to cooked) mode, or
4753 even close them. The command ``run < foo > bar'' works as expected,
4754 and ``info terminal'' reports useful information about the debuggee's
4755 terminal, including raw/cooked mode, redirection, etc.
4757 The DJGPP version now uses termios functions for console I/O, which
4758 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4761 DOS-style file names with drive letters are now fully supported by
4764 It is now possible to debug DJGPP programs that switch their working
4765 directory. It is also possible to rerun the debuggee any number of
4766 times without restarting GDB; thus, you can use the same setup,
4767 breakpoints, etc. for many debugging sessions.
4769 * New native configurations
4771 ARM GNU/Linux arm*-*-linux*
4772 PowerPC GNU/Linux powerpc-*-linux*
4776 Motorola MCore mcore-*-*
4777 x86 VxWorks i[3456]86-*-vxworks*
4778 PowerPC VxWorks powerpc-*-vxworks*
4779 TI TMS320C80 tic80-*-*
4781 * OBSOLETE configurations
4783 Altos 3068 m68*-altos-*
4784 Convex c1-*-*, c2-*-*
4786 ARM RISCix arm-*-* (as host)
4789 Configurations that have been declared obsolete will be commented out,
4790 but the code will be left in place. If there is no activity to revive
4791 these configurations before the next release of GDB, the sources will
4792 be permanently REMOVED.
4794 * Gould support removed
4796 Support for the Gould PowerNode and NP1 has been removed.
4798 * New features for SVR4
4800 On SVR4 native platforms (such as Solaris), if you attach to a process
4801 without first loading a symbol file, GDB will now attempt to locate and
4802 load symbols from the running process's executable file.
4804 * Many C++ enhancements
4806 C++ support has been greatly improved. Overload resolution now works properly
4807 in almost all cases. RTTI support is on the way.
4809 * Remote targets can connect to a sub-program
4811 A popen(3) style serial-device has been added. This device starts a
4812 sub-process (such as a stand-alone simulator) and then communicates
4813 with that. The sub-program to run is specified using the syntax
4814 ``|<program> <args>'' vis:
4816 (gdb) set remotedebug 1
4817 (gdb) target extended-remote |mn10300-elf-sim program-args
4819 * MIPS 64 remote protocol
4821 A long standing bug in the mips64 remote protocol where by GDB
4822 expected certain 32 bit registers (ex SR) to be transfered as 32
4823 instead of 64 bits has been fixed.
4825 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4826 added to provide backward compatibility with older versions of GDB.
4828 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4830 The command ``set remotebinarydownload'' command has been replaced by
4831 ``set remote X-packet''. Other commands in ``set remote'' family
4832 include ``set remote P-packet''.
4834 * Breakpoint commands accept ranges.
4836 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4837 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4838 ``tracepoint passcount'' also accepts a range of tracepoints.
4840 * ``apropos'' command added.
4842 The ``apropos'' command searches through command names and
4843 documentation strings, printing out matches, making it much easier to
4844 try to find a command that does what you are looking for.
4848 A new machine oriented interface (MI) has been added to GDB. This
4849 interface is designed for debug environments running GDB as a separate
4850 process. This is part of the long term libGDB project. See the
4851 "GDB/MI" chapter of the GDB manual for further information. It can be
4852 enabled by configuring with:
4854 .../configure --enable-gdbmi
4856 *** Changes in GDB-4.18:
4858 * New native configurations
4860 HP-UX 10.20 hppa*-*-hpux10.20
4861 HP-UX 11.x hppa*-*-hpux11.0*
4862 M68K GNU/Linux m68*-*-linux*
4866 Fujitsu FR30 fr30-*-elf*
4867 Intel StrongARM strongarm-*-*
4868 Mitsubishi D30V d30v-*-*
4870 * OBSOLETE configurations
4872 Gould PowerNode, NP1 np1-*-*, pn-*-*
4874 Configurations that have been declared obsolete will be commented out,
4875 but the code will be left in place. If there is no activity to revive
4876 these configurations before the next release of GDB, the sources will
4877 be permanently REMOVED.
4881 As a compatibility experiment, GDB's source files buildsym.h and
4882 buildsym.c have been converted to pure standard C, no longer
4883 containing any K&R compatibility code. We believe that all systems in
4884 use today either come with a standard C compiler, or have a GCC port
4885 available. If this is not true, please report the affected
4886 configuration to bug-gdb@gnu.org immediately. See the README file for
4887 information about getting a standard C compiler if you don't have one
4892 GDB now uses readline 2.2.
4894 * set extension-language
4896 You can now control the mapping between filename extensions and source
4897 languages by using the `set extension-language' command. For instance,
4898 you can ask GDB to treat .c files as C++ by saying
4899 set extension-language .c c++
4900 The command `info extensions' lists all of the recognized extensions
4901 and their associated languages.
4903 * Setting processor type for PowerPC and RS/6000
4905 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4906 you can use the `set processor' command to specify what variant of the
4907 PowerPC family you are debugging. The command
4911 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4912 following PowerPC and RS6000 variants:
4914 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4915 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4917 403GC IBM PowerPC 403GC
4918 505 Motorola PowerPC 505
4919 860 Motorola PowerPC 860 or 850
4920 601 Motorola PowerPC 601
4921 602 Motorola PowerPC 602
4922 603 Motorola/IBM PowerPC 603 or 603e
4923 604 Motorola PowerPC 604 or 604e
4924 750 Motorola/IBM PowerPC 750 or 750
4926 At the moment, this command just tells GDB what to name the
4927 special-purpose processor registers. Since almost all the affected
4928 registers are inaccessible to user-level programs, this command is
4929 only useful for remote debugging in its present form.
4933 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4934 more extensive support for HP-UX. Added features include shared
4935 library support, kernel threads and hardware watchpoints for 11.00,
4936 support for HP's ANSI C and C++ compilers, and a compatibility mode
4937 for xdb and dbx commands.
4941 HP's donation includes the new concept of catchpoints, which is a
4942 generalization of the old catch command. On HP-UX, it is now possible
4943 to catch exec, fork, and vfork, as well as library loading.
4945 This means that the existing catch command has changed; its first
4946 argument now specifies the type of catch to be set up. See the
4947 output of "help catch" for a list of catchpoint types.
4949 * Debugging across forks
4951 On HP-UX, you can choose which process to debug when a fork() happens
4956 HP has donated a curses-based terminal user interface (TUI). To get
4957 it, build with --enable-tui. Although this can be enabled for any
4958 configuration, at present it only works for native HP debugging.
4960 * GDB remote protocol additions
4962 A new protocol packet 'X' that writes binary data is now available.
4963 Default behavior is to try 'X', then drop back to 'M' if the stub
4964 fails to respond. The settable variable `remotebinarydownload'
4965 allows explicit control over the use of 'X'.
4967 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4968 full 64-bit address. The command
4970 set remoteaddresssize 32
4972 can be used to revert to the old behaviour. For existing remote stubs
4973 the change should not be noticed, as the additional address information
4976 In order to assist in debugging stubs, you may use the maintenance
4977 command `packet' to send any text string to the stub. For instance,
4979 maint packet heythere
4981 sends the packet "$heythere#<checksum>". Note that it is very easy to
4982 disrupt a debugging session by sending the wrong packet at the wrong
4985 The compare-sections command allows you to compare section data on the
4986 target to what is in the executable file without uploading or
4987 downloading, by comparing CRC checksums.
4989 * Tracing can collect general expressions
4991 You may now collect general expressions at tracepoints. This requires
4992 further additions to the target-side stub; see tracepoint.c and
4993 doc/agentexpr.texi for further details.
4995 * mask-address variable for Mips
4997 For Mips targets, you may control the zeroing of the upper 32 bits of
4998 a 64-bit address by entering `set mask-address on'. This is mainly
4999 of interest to users of embedded R4xxx and R5xxx processors.
5001 * Higher serial baud rates
5003 GDB's serial code now allows you to specify baud rates 57600, 115200,
5004 230400, and 460800 baud. (Note that your host system may not be able
5005 to achieve all of these rates.)
5009 The i960 configuration now includes an initial implementation of a
5010 builtin simulator, contributed by Jim Wilson.
5013 *** Changes in GDB-4.17:
5015 * New native configurations
5017 Alpha GNU/Linux alpha*-*-linux*
5018 Unixware 2.x i[3456]86-unixware2*
5019 Irix 6.x mips*-sgi-irix6*
5020 PowerPC GNU/Linux powerpc-*-linux*
5021 PowerPC Solaris powerpcle-*-solaris*
5022 Sparc GNU/Linux sparc-*-linux*
5023 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5027 Argonaut Risc Chip (ARC) arc-*-*
5028 Hitachi H8/300S h8300*-*-*
5029 Matsushita MN10200 w/simulator mn10200-*-*
5030 Matsushita MN10300 w/simulator mn10300-*-*
5031 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5032 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5033 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5034 Mitsubishi D10V w/simulator d10v-*-*
5035 Mitsubishi M32R/D w/simulator m32r-*-elf*
5036 Tsqware Sparclet sparclet-*-*
5037 NEC V850 w/simulator v850-*-*
5039 * New debugging protocols
5041 ARM with RDI protocol arm*-*-*
5042 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5043 DDB and LSI variants of PMON protocol mips*-*-*
5044 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5045 PowerPC with SDS protocol powerpc{,le}-*-eabi
5046 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5050 All configurations can now understand and use the DWARF 2 debugging
5051 format. The choice is automatic, if the symbol file contains DWARF 2
5056 GDB now includes basic Java language support. This support is
5057 only useful with Java compilers that produce native machine code.
5059 * solib-absolute-prefix and solib-search-path
5061 For SunOS and SVR4 shared libraries, you may now set the prefix for
5062 loading absolute shared library symbol files, and the search path for
5063 locating non-absolute shared library symbol files.
5065 * Live range splitting
5067 GDB can now effectively debug code for which GCC has performed live
5068 range splitting as part of its optimization. See gdb/doc/LRS for
5069 more details on the expected format of the stabs information.
5073 GDB's support for the GNU Hurd, including thread debugging, has been
5074 updated to work with current versions of the Hurd.
5078 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5079 instruction set. ARM GDB automatically detects when Thumb
5080 instructions are in use, and adjusts disassembly and backtracing
5085 GDB's MIPS target configurations now handle the MIP16 16-bit
5090 GDB now includes support for overlays; if an executable has been
5091 linked such that multiple sections are based at the same address, GDB
5092 will decide which section to use for symbolic info. You can choose to
5093 control the decision manually, using overlay commands, or implement
5094 additional target-side support and use "overlay load-target" to bring
5095 in the overlay mapping. Do "help overlay" for more detail.
5099 The command "info symbol <address>" displays information about
5100 the symbol at the specified address.
5104 The standard remote protocol now includes an extension that allows
5105 asynchronous collection and display of trace data. This requires
5106 extensive support in the target-side debugging stub. Tracing mode
5107 includes a new interaction mode in GDB and new commands: see the
5108 file tracepoint.c for more details.
5112 Configurations for embedded MIPS now include a simulator contributed
5113 by Cygnus Solutions. The simulator supports the instruction sets
5114 of most MIPS variants.
5118 Sparc configurations may now include the ERC32 simulator contributed
5119 by the European Space Agency. The simulator is not built into
5120 Sparc targets by default; configure with --enable-sim to include it.
5124 For target configurations that may include multiple variants of a
5125 basic architecture (such as MIPS and SH), you may now set the
5126 architecture explicitly. "set arch" sets, "info arch" lists
5127 the possible architectures.
5129 *** Changes in GDB-4.16:
5131 * New native configurations
5133 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5134 M68K NetBSD m68k-*-netbsd*
5135 PowerPC AIX 4.x powerpc-*-aix*
5136 PowerPC MacOS powerpc-*-macos*
5137 PowerPC Windows NT powerpcle-*-cygwin32
5138 RS/6000 AIX 4.x rs6000-*-aix4*
5142 ARM with RDP protocol arm-*-*
5143 I960 with MON960 i960-*-coff
5144 MIPS VxWorks mips*-*-vxworks*
5145 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5146 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5148 Matra Sparclet sparclet-*-*
5152 The powerpc-eabi configuration now includes the PSIM simulator,
5153 contributed by Andrew Cagney, with assistance from Mike Meissner.
5154 PSIM is a very elaborate model of the PowerPC, including not only
5155 basic instruction set execution, but also details of execution unit
5156 performance and I/O hardware. See sim/ppc/README for more details.
5160 GDB now works with Solaris 2.5.
5162 * Windows 95/NT native
5164 GDB will now work as a native debugger on Windows 95 and Windows NT.
5165 To build it from source, you must use the "gnu-win32" environment,
5166 which uses a DLL to emulate enough of Unix to run the GNU tools.
5167 Further information, binaries, and sources are available at
5168 ftp.cygnus.com, under pub/gnu-win32.
5170 * dont-repeat command
5172 If a user-defined command includes the command `dont-repeat', then the
5173 command will not be repeated if the user just types return. This is
5174 useful if the command is time-consuming to run, so that accidental
5175 extra keystrokes don't run the same command many times.
5177 * Send break instead of ^C
5179 The standard remote protocol now includes an option to send a break
5180 rather than a ^C to the target in order to interrupt it. By default,
5181 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5183 * Remote protocol timeout
5185 The standard remote protocol includes a new variable `remotetimeout'
5186 that allows you to set the number of seconds before GDB gives up trying
5187 to read from the target. The default value is 2.
5189 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5191 By default GDB will automatically keep track of objects as they are
5192 loaded and unloaded by the dynamic linker. By using the command `set
5193 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5194 when shared library events occur, thus allowing you to set breakpoints
5195 in shared libraries which are explicitly loaded by the inferior.
5197 Note this feature does not work on hpux8. On hpux9 you must link
5198 /usr/lib/end.o into your program. This feature should work
5199 automatically on hpux10.
5201 * Irix 5.x hardware watchpoint support
5203 Irix 5 configurations now support the use of hardware watchpoints.
5205 * Mips protocol "SYN garbage limit"
5207 When debugging a Mips target using the `target mips' protocol, you
5208 may set the number of characters that GDB will ignore by setting
5209 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5210 every character. The default value is 1050.
5212 * Recording and replaying remote debug sessions
5214 If you set `remotelogfile' to the name of a file, gdb will write to it
5215 a recording of a remote debug session. This recording may then be
5216 replayed back to gdb using "gdbreplay". See gdbserver/README for
5217 details. This is useful when you have a problem with GDB while doing
5218 remote debugging; you can make a recording of the session and send it
5219 to someone else, who can then recreate the problem.
5221 * Speedups for remote debugging
5223 GDB includes speedups for downloading and stepping MIPS systems using
5224 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5225 and more efficient S-record downloading.
5227 * Memory use reductions and statistics collection
5229 GDB now uses less memory and reports statistics about memory usage.
5230 Try the `maint print statistics' command, for example.
5232 *** Changes in GDB-4.15:
5234 * Psymtabs for XCOFF
5236 The symbol reader for AIX GDB now uses partial symbol tables. This
5237 can greatly improve startup time, especially for large executables.
5239 * Remote targets use caching
5241 Remote targets now use a data cache to speed up communication with the
5242 remote side. The data cache could lead to incorrect results because
5243 it doesn't know about volatile variables, thus making it impossible to
5244 debug targets which use memory mapped I/O devices. `set remotecache
5245 off' turns the the data cache off.
5247 * Remote targets may have threads
5249 The standard remote protocol now includes support for multiple threads
5250 in the target system, using new protocol commands 'H' and 'T'. See
5251 gdb/remote.c for details.
5255 If GDB is configured with `--enable-netrom', then it will include
5256 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5257 acts as though it is a bank of ROM on the target board, but you can
5258 write into it over the network. GDB's support consists only of
5259 support for fast loading into the emulated ROM; to debug, you must use
5260 another protocol, such as standard remote protocol. The usual
5261 sequence is something like
5263 target nrom <netrom-hostname>
5265 target remote <netrom-hostname>:1235
5269 GDB now includes support for the Apple Macintosh, as a host only. It
5270 may be run as either an MPW tool or as a standalone application, and
5271 it can debug through the serial port. All the usual GDB commands are
5272 available, but to the target command, you must supply "serial" as the
5273 device type instead of "/dev/ttyXX". See mpw-README in the main
5274 directory for more information on how to build. The MPW configuration
5275 scripts */mpw-config.in support only a few targets, and only the
5276 mips-idt-ecoff target has been tested.
5280 GDB configuration now uses autoconf. This is not user-visible,
5281 but does simplify configuration and building.
5285 GDB now supports hpux10.
5287 *** Changes in GDB-4.14:
5289 * New native configurations
5291 x86 FreeBSD i[345]86-*-freebsd
5292 x86 NetBSD i[345]86-*-netbsd
5293 NS32k NetBSD ns32k-*-netbsd
5294 Sparc NetBSD sparc-*-netbsd
5298 A29K VxWorks a29k-*-vxworks
5299 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5300 CPU32 EST-300 emulator m68*-*-est*
5301 PowerPC ELF powerpc-*-elf
5304 * Alpha OSF/1 support for procfs
5306 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5307 possible to attach to running processes. As the mounting of the /proc
5308 filesystem is optional on the Alpha, GDB automatically determines
5309 the availability of /proc during startup. This can lead to problems
5310 if /proc is unmounted after GDB has been started.
5312 * Arguments to user-defined commands
5314 User commands may accept up to 10 arguments separated by whitespace.
5315 Arguments are accessed within the user command via $arg0..$arg9. A
5318 print $arg0 + $arg1 + $arg2
5320 To execute the command use:
5323 Defines the command "adder" which prints the sum of its three arguments.
5324 Note the arguments are text substitutions, so they may reference variables,
5325 use complex expressions, or even perform inferior function calls.
5327 * New `if' and `while' commands
5329 This makes it possible to write more sophisticated user-defined
5330 commands. Both commands take a single argument, which is the
5331 expression to evaluate, and must be followed by the commands to
5332 execute, one per line, if the expression is nonzero, the list being
5333 terminated by the word `end'. The `if' command list may include an
5334 `else' word, which causes the following commands to be executed only
5335 if the expression is zero.
5337 * Fortran source language mode
5339 GDB now includes partial support for Fortran 77. It will recognize
5340 Fortran programs and can evaluate a subset of Fortran expressions, but
5341 variables and functions may not be handled correctly. GDB will work
5342 with G77, but does not yet know much about symbols emitted by other
5345 * Better HPUX support
5347 Most debugging facilities now work on dynamic executables for HPPAs
5348 running hpux9 or later. You can attach to running dynamically linked
5349 processes, but by default the dynamic libraries will be read-only, so
5350 for instance you won't be able to put breakpoints in them. To change
5351 that behavior do the following before running the program:
5357 This will cause the libraries to be mapped private and read-write.
5358 To revert to the normal behavior, do this:
5364 You cannot set breakpoints or examine data in the library until after
5365 the library is loaded if the function/data symbols do not have
5368 GDB can now also read debug symbols produced by the HP C compiler on
5369 HPPAs (sorry, no C++, Fortran or 68k support).
5371 * Target byte order now dynamically selectable
5373 You can choose which byte order to use with a target system, via the
5374 commands "set endian big" and "set endian little", and you can see the
5375 current setting by using "show endian". You can also give the command
5376 "set endian auto", in which case GDB will use the byte order
5377 associated with the executable. Currently, only embedded MIPS
5378 configurations support dynamic selection of target byte order.
5380 * New DOS host serial code
5382 This version uses DPMI interrupts to handle buffered I/O, so you
5383 no longer need to run asynctsr when debugging boards connected to
5386 *** Changes in GDB-4.13:
5388 * New "complete" command
5390 This lists all the possible completions for the rest of the line, if it
5391 were to be given as a command itself. This is intended for use by emacs.
5393 * Trailing space optional in prompt
5395 "set prompt" no longer adds a space for you after the prompt you set. This
5396 allows you to set a prompt which ends in a space or one that does not.
5398 * Breakpoint hit counts
5400 "info break" now displays a count of the number of times the breakpoint
5401 has been hit. This is especially useful in conjunction with "ignore"; you
5402 can ignore a large number of breakpoint hits, look at the breakpoint info
5403 to see how many times the breakpoint was hit, then run again, ignoring one
5404 less than that number, and this will get you quickly to the last hit of
5407 * Ability to stop printing at NULL character
5409 "set print null-stop" will cause GDB to stop printing the characters of
5410 an array when the first NULL is encountered. This is useful when large
5411 arrays actually contain only short strings.
5413 * Shared library breakpoints
5415 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5416 breakpoints in shared libraries before the executable is run.
5418 * Hardware watchpoints
5420 There is a new hardware breakpoint for the watch command for sparclite
5421 targets. See gdb/sparclite/hw_breakpoint.note.
5423 Hardware watchpoints are also now supported under GNU/Linux.
5427 Annotations have been added. These are for use with graphical interfaces,
5428 and are still experimental. Currently only gdba.el uses these.
5430 * Improved Irix 5 support
5432 GDB now works properly with Irix 5.2.
5434 * Improved HPPA support
5436 GDB now works properly with the latest GCC and GAS.
5438 * New native configurations
5440 Sequent PTX4 i[34]86-sequent-ptx4
5441 HPPA running OSF/1 hppa*-*-osf*
5442 Atari TT running SVR4 m68*-*-sysv4*
5443 RS/6000 LynxOS rs6000-*-lynxos*
5447 OS/9000 i[34]86-*-os9k
5448 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5451 * Hitachi SH7000 and E7000-PC ICE support
5453 There is now support for communicating with the Hitachi E7000-PC ICE.
5454 This is available automatically when GDB is configured for the SH.
5458 As usual, a variety of small fixes and improvements, both generic
5459 and configuration-specific. See the ChangeLog for more detail.
5461 *** Changes in GDB-4.12:
5463 * Irix 5 is now supported
5467 GDB-4.12 on the HPPA has a number of changes which make it unable
5468 to debug the output from the currently released versions of GCC and
5469 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5470 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5471 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5474 *** Changes in GDB-4.11:
5476 * User visible changes:
5480 The "set remotedebug" option is now consistent between the mips remote
5481 target, remote targets using the gdb-specific protocol, UDI (AMD's
5482 debug protocol for the 29k) and the 88k bug monitor. It is now an
5483 integer specifying a debug level (normally 0 or 1, but 2 means more
5484 debugging info for the mips target).
5486 * DEC Alpha native support
5488 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5489 debug info, but GDB works fairly well with the DEC compiler and should
5490 work with a future GCC release. See the README file for a few
5491 Alpha-specific notes.
5493 * Preliminary thread implementation
5495 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5497 * LynxOS native and target support for 386
5499 This release has been hosted on LynxOS 2.2, and also can be configured
5500 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5503 * Improvements in C++ mangling/demangling.
5505 This release has much better g++ debugging, specifically in name
5506 mangling/demangling, virtual function calls, print virtual table,
5507 call methods, ...etc.
5509 *** Changes in GDB-4.10:
5511 * User visible changes:
5513 Remote debugging using the GDB-specific (`target remote') protocol now
5514 supports the `load' command. This is only useful if you have some
5515 other way of getting the stub to the target system, and you can put it
5516 somewhere in memory where it won't get clobbered by the download.
5518 Filename completion now works.
5520 When run under emacs mode, the "info line" command now causes the
5521 arrow to point to the line specified. Also, "info line" prints
5522 addresses in symbolic form (as well as hex).
5524 All vxworks based targets now support a user settable option, called
5525 vxworks-timeout. This option represents the number of seconds gdb
5526 should wait for responses to rpc's. You might want to use this if
5527 your vxworks target is, perhaps, a slow software simulator or happens
5528 to be on the far side of a thin network line.
5532 This release contains support for using a DEC alpha as a GDB host for
5533 cross debugging. Native alpha debugging is not supported yet.
5536 *** Changes in GDB-4.9:
5540 This is the first GDB release which is accompanied by a matching testsuite.
5541 The testsuite requires installation of dejagnu, which should be available
5542 via ftp from most sites that carry GNU software.
5546 'Cfront' style demangling has had its name changed to 'ARM' style, to
5547 emphasize that it was written from the specifications in the C++ Annotated
5548 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5549 disclaimers, it still generated too much confusion with users attempting to
5550 use gdb with AT&T cfront.
5554 GDB now uses a standard remote interface to a simulator library.
5555 So far, the library contains simulators for the Zilog Z8001/2, the
5556 Hitachi H8/300, H8/500 and Super-H.
5558 * New targets supported
5560 H8/300 simulator h8300-hitachi-hms or h8300hms
5561 H8/500 simulator h8500-hitachi-hms or h8500hms
5562 SH simulator sh-hitachi-hms or sh
5563 Z8000 simulator z8k-zilog-none or z8ksim
5564 IDT MIPS board over serial line mips-idt-ecoff
5566 Cross-debugging to GO32 targets is supported. It requires a custom
5567 version of the i386-stub.c module which is integrated with the
5568 GO32 memory extender.
5570 * New remote protocols
5572 MIPS remote debugging protocol.
5574 * New source languages supported
5576 This version includes preliminary support for Chill, a Pascal like language
5577 used by telecommunications companies. Chill support is also being integrated
5578 into the GNU compiler, but we don't know when it will be publically available.
5581 *** Changes in GDB-4.8:
5583 * HP Precision Architecture supported
5585 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5586 version of this support was available as a set of patches from the
5587 University of Utah. GDB does not support debugging of programs
5588 compiled with the HP compiler, because HP will not document their file
5589 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5590 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5592 Many problems in the preliminary version have been fixed.
5594 * Faster and better demangling
5596 We have improved template demangling and fixed numerous bugs in the GNU style
5597 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5598 character types (wchar_t) are now supported. Demangling of each symbol is now
5599 only done once, and is cached when the symbol table for a file is read in.
5600 This results in a small increase in memory usage for C programs, a moderate
5601 increase in memory usage for C++ programs, and a fantastic speedup in
5604 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5605 from the specifications in the Annotated Reference Manual, which AT&T's
5606 compiler does not actually implement.
5608 * G++ multiple inheritance compiler problem
5610 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5611 inheritance lattices was reworked to properly discover ambiguities. We
5612 recently found an example which causes this new algorithm to fail in a
5613 very subtle way, producing bad debug information for those classes.
5614 The file 'gcc.patch' (in this directory) can be applied to gcc to
5615 circumvent the problem. A future GCC release will contain a complete
5618 The previous G++ debug info problem (mentioned below for the gdb-4.7
5619 release) is fixed in gcc version 2.3.2.
5621 * Improved configure script
5623 The `configure' script will now attempt to guess your system type if
5624 you don't supply a host system type. The old scheme of supplying a
5625 host system triplet is preferable over using this. All the magic is
5626 done in the new `config.guess' script. Examine it for details.
5628 We have also brought our configure script much more in line with the FSF's
5629 version. It now supports the --with-xxx options. In particular,
5630 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5631 The resulting GDB will not be able to read arbitrary object file formats --
5632 only the format ``expected'' to be used on the configured target system.
5633 We hope to make this the default in a future release.
5635 * Documentation improvements
5637 There's new internal documentation on how to modify GDB, and how to
5638 produce clean changes to the code. We implore people to read it
5639 before submitting changes.
5641 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5642 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5643 `info' files are also provided. To build `info' files from scratch,
5644 you will need the latest `makeinfo' release, which will be available in
5645 a future texinfo-X.Y release.
5647 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5648 We're not sure exactly which versions have this problem, but it has
5649 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5650 or better. If that isn't possible, there is a patch in
5651 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5652 around this problem.
5656 GDB now supports array constants that can be used in expressions typed in by
5657 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5658 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5661 The new directory `gdb/sparclite' contains a program that demonstrates
5662 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5664 * New native hosts supported
5666 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5667 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5669 * New targets supported
5671 AMD 29k family via UDI a29k-amd-udi or udi29k
5673 * New file formats supported
5675 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5676 HPUX core files, and SCO 3.2v2 core files.
5680 Attaching to processes now works again; thanks for the many bug reports.
5682 We have also stomped on a bunch of core dumps caused by
5683 printf_filtered("%s") problems.
5685 We eliminated a copyright problem on the rpc and ptrace header files
5686 for VxWorks, which was discovered at the last minute during the 4.7
5687 release. You should now be able to build a VxWorks GDB.
5689 You can now interrupt gdb while an attached process is running. This
5690 will cause the attached process to stop, and give control back to GDB.
5692 We fixed problems caused by using too many file descriptors
5693 for reading symbols from object files and libraries. This was
5694 especially a problem for programs that used many (~100) shared
5697 The `step' command now only enters a subroutine if there is line number
5698 information for the subroutine. Otherwise it acts like the `next'
5699 command. Previously, `step' would enter subroutines if there was
5700 any debugging information about the routine. This avoids problems
5701 when using `cc -g1' on MIPS machines.
5703 * Internal improvements
5705 GDB's internal interfaces have been improved to make it easier to support
5706 debugging of multiple languages in the future.
5708 GDB now uses a common structure for symbol information internally.
5709 Minimal symbols (derived from linkage symbols in object files), partial
5710 symbols (from a quick scan of debug information), and full symbols
5711 contain a common subset of information, making it easier to write
5712 shared code that handles any of them.
5714 * New command line options
5716 We now accept --silent as an alias for --quiet.
5720 The memory-mapped-malloc library is now licensed under the GNU Library
5721 General Public License.
5723 *** Changes in GDB-4.7:
5725 * Host/native/target split
5727 GDB has had some major internal surgery to untangle the support for
5728 hosts and remote targets. Now, when you configure GDB for a remote
5729 target, it will no longer load in all of the support for debugging
5730 local programs on the host. When fully completed and tested, this will
5731 ensure that arbitrary host/target combinations are possible.
5733 The primary conceptual shift is to separate the non-portable code in
5734 GDB into three categories. Host specific code is required any time GDB
5735 is compiled on that host, regardless of the target. Target specific
5736 code relates to the peculiarities of the target, but can be compiled on
5737 any host. Native specific code is everything else: it can only be
5738 built when the host and target are the same system. Child process
5739 handling and core file support are two common `native' examples.
5741 GDB's use of /proc for controlling Unix child processes is now cleaner.
5742 It has been split out into a single module under the `target_ops' vector,
5743 plus two native-dependent functions for each system that uses /proc.
5745 * New hosts supported
5747 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5748 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5749 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5751 * New targets supported
5753 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5754 68030 and CPU32 m68030-*-*, m68332-*-*
5756 * New native hosts supported
5758 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5759 (386bsd is not well tested yet)
5760 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5762 * New file formats supported
5764 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5765 supports reading of `a.out.adobe' object files, which are an a.out
5766 format extended with minimal information about multiple sections.
5770 `show copying' is the same as the old `info copying'.
5771 `show warranty' is the same as `info warrantee'.
5772 These were renamed for consistency. The old commands continue to work.
5774 `info handle' is a new alias for `info signals'.
5776 You can now define pre-command hooks, which attach arbitrary command
5777 scripts to any command. The commands in the hook will be executed
5778 prior to the user's command. You can also create a hook which will be
5779 executed whenever the program stops. See gdb.texinfo.
5783 We now deal with Cfront style name mangling, and can even extract type
5784 info from mangled symbols. GDB can automatically figure out which
5785 symbol mangling style your C++ compiler uses.
5787 Calling of methods and virtual functions has been improved as well.
5791 The crash that occured when debugging Sun Ansi-C compiled binaries is
5792 fixed. This was due to mishandling of the extra N_SO stabs output
5795 We also finally got Ultrix 4.2 running in house, and fixed core file
5796 support, with help from a dozen people on the net.
5798 John M. Farrell discovered that the reason that single-stepping was so
5799 slow on all of the Mips based platforms (primarily SGI and DEC) was
5800 that we were trying to demangle and lookup a symbol used for internal
5801 purposes on every instruction that was being stepped through. Changing
5802 the name of that symbol so that it couldn't be mistaken for a C++
5803 mangled symbol sped things up a great deal.
5805 Rich Pixley sped up symbol lookups in general by getting much smarter
5806 about when C++ symbol mangling is necessary. This should make symbol
5807 completion (TAB on the command line) much faster. It's not as fast as
5808 we'd like, but it's significantly faster than gdb-4.6.
5812 A new user controllable variable 'call_scratch_address' can
5813 specify the location of a scratch area to be used when GDB
5814 calls a function in the target. This is necessary because the
5815 usual method of putting the scratch area on the stack does not work
5816 in systems that have separate instruction and data spaces.
5818 We integrated changes to support the 29k UDI (Universal Debugger
5819 Interface), but discovered at the last minute that we didn't have all
5820 of the appropriate copyright paperwork. We are working with AMD to
5821 resolve this, and hope to have it available soon.
5825 We have sped up the remote serial line protocol, especially for targets
5826 with lots of registers. It now supports a new `expedited status' ('T')
5827 message which can be used in place of the existing 'S' status message.
5828 This allows the remote stub to send only the registers that GDB
5829 needs to make a quick decision about single-stepping or conditional
5830 breakpoints, eliminating the need to fetch the entire register set for
5831 each instruction being stepped through.
5833 The GDB remote serial protocol now implements a write-through cache for
5834 registers, only re-reading the registers if the target has run.
5836 There is also a new remote serial stub for SPARC processors. You can
5837 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5838 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5839 processor with a serial port.
5843 Configure.in files have become much easier to read and modify. A new
5844 `table driven' format makes it more obvious what configurations are
5845 supported, and what files each one uses.
5849 There is a new opcodes library which will eventually contain all of the
5850 disassembly routines and opcode tables. At present, it only contains
5851 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5852 disassembler (binutils/objdump) to share these routines.
5854 The libiberty library is now copylefted under the GNU Library General
5855 Public License. This allows more liberal use, and was done so libg++
5856 can use it. This makes no difference to GDB, since the Library License
5857 grants all the rights from the General Public License.
5861 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5862 reference to the stabs symbol info used by the debugger. It is (as far
5863 as we know) the only published document on this fascinating topic. We
5864 encourage you to read it, compare it to the stabs information on your
5865 system, and send improvements on the document in general (to
5866 bug-gdb@prep.ai.mit.edu).
5868 And, of course, many bugs have been fixed.
5871 *** Changes in GDB-4.6:
5873 * Better support for C++ function names
5875 GDB now accepts as input the "demangled form" of C++ overloaded function
5876 names and member function names, and can do command completion on such names
5877 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5878 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5879 Make use of command completion, it is your friend.
5881 GDB also now accepts a variety of C++ mangled symbol formats. They are
5882 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5883 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5884 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5885 for the list of formats.
5887 * G++ symbol mangling problem
5889 Recent versions of gcc have a bug in how they emit debugging information for
5890 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5891 directory) can be applied to gcc to fix the problem. Alternatively, if you
5892 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5893 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5894 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5897 * New 'maintenance' command
5899 All of the commands related to hacking GDB internals have been moved out of
5900 the main command set, and now live behind the 'maintenance' command. This
5901 can also be abbreviated as 'mt'. The following changes were made:
5903 dump-me -> maintenance dump-me
5904 info all-breakpoints -> maintenance info breakpoints
5905 printmsyms -> maintenance print msyms
5906 printobjfiles -> maintenance print objfiles
5907 printpsyms -> maintenance print psymbols
5908 printsyms -> maintenance print symbols
5910 The following commands are new:
5912 maintenance demangle Call internal GDB demangler routine to
5913 demangle a C++ link name and prints the result.
5914 maintenance print type Print a type chain for a given symbol
5916 * Change to .gdbinit file processing
5918 We now read the $HOME/.gdbinit file before processing the argv arguments
5919 (e.g. reading symbol files or core files). This allows global parameters to
5920 be set, which will apply during the symbol reading. The ./.gdbinit is still
5921 read after argv processing.
5923 * New hosts supported
5925 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5927 GNU/Linux support i386-unknown-linux or linux
5929 We are also including code to support the HP/PA running BSD and HPUX. This
5930 is almost guaranteed not to work, as we didn't have time to test or build it
5931 for this release. We are including it so that the more adventurous (or
5932 masochistic) of you can play with it. We also had major problems with the
5933 fact that the compiler that we got from HP doesn't support the -g option.
5936 * New targets supported
5938 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5940 * More smarts about finding #include files
5942 GDB now remembers the compilation directory for all include files, and for
5943 all files from which C is generated (like yacc and lex sources). This
5944 greatly improves GDB's ability to find yacc/lex sources, and include files,
5945 especially if you are debugging your program from a directory different from
5946 the one that contains your sources.
5948 We also fixed a bug which caused difficulty with listing and setting
5949 breakpoints in include files which contain C code. (In the past, you had to
5950 try twice in order to list an include file that you hadn't looked at before.)
5952 * Interesting infernals change
5954 GDB now deals with arbitrary numbers of sections, where the symbols for each
5955 section must be relocated relative to that section's landing place in the
5956 target's address space. This work was needed to support ELF with embedded
5957 stabs used by Solaris-2.0.
5959 * Bug fixes (of course!)
5961 There have been loads of fixes for the following things:
5962 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5963 i960, stabs, DOS(GO32), procfs, etc...
5965 See the ChangeLog for details.
5967 *** Changes in GDB-4.5:
5969 * New machines supported (host and target)
5971 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5973 SGI Irix-4.x mips-sgi-irix4 or iris4
5975 * New malloc package
5977 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5978 Mmalloc is capable of handling mutiple heaps of memory. It is also
5979 capable of saving a heap to a file, and then mapping it back in later.
5980 This can be used to greatly speedup the startup of GDB by using a
5981 pre-parsed symbol table which lives in a mmalloc managed heap. For
5982 more details, please read mmalloc/mmalloc.texi.
5986 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5987 'help info proc' for details.
5989 * MIPS ecoff symbol table format
5991 The code that reads MIPS symbol table format is now supported on all hosts.
5992 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5995 * File name changes for MS-DOS
5997 Many files in the config directories have been renamed to make it easier to
5998 support GDB on MS-DOSe systems (which have very restrictive file name
5999 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6000 environment) is close to working but has some remaining problems. Note
6001 that debugging of DOS programs is not supported, due to limitations
6002 in the ``operating system'', but it can be used to host cross-debugging.
6004 * Cross byte order fixes
6006 Many fixes have been made to support cross debugging of Sparc and MIPS
6007 targets from hosts whose byte order differs.
6009 * New -mapped and -readnow options
6011 If memory-mapped files are available on your system through the 'mmap'
6012 system call, you can use the -mapped option on the `file' or
6013 `symbol-file' commands to cause GDB to write the symbols from your
6014 program into a reusable file. If the program you are debugging is
6015 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6016 Future GDB debugging sessions will notice the presence of this file,
6017 and will quickly map in symbol information from it, rather than reading
6018 the symbol table from the executable program. Using the '-mapped'
6019 option in a GDB `file' or `symbol-file' command has the same effect as
6020 starting GDB with the '-mapped' command-line option.
6022 You can cause GDB to read the entire symbol table immediately by using
6023 the '-readnow' option with any of the commands that load symbol table
6024 information (or on the GDB command line). This makes the command
6025 slower, but makes future operations faster.
6027 The -mapped and -readnow options are typically combined in order to
6028 build a `fred.syms' file that contains complete symbol information.
6029 A simple GDB invocation to do nothing but build a `.syms' file for future
6032 gdb -batch -nx -mapped -readnow programname
6034 The `.syms' file is specific to the host machine on which GDB is run.
6035 It holds an exact image of GDB's internal symbol table. It cannot be
6036 shared across multiple host platforms.
6038 * longjmp() handling
6040 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6041 siglongjmp() without losing control. This feature has not yet been ported to
6042 all systems. It currently works on many 386 platforms, all MIPS-based
6043 platforms (SGI, DECstation, etc), and Sun3/4.
6047 Preliminary work has been put in to support the new Solaris OS from Sun. At
6048 this time, it can control and debug processes, but it is not capable of
6053 As always, many many bug fixes. The major areas were with g++, and mipsread.
6054 People using the MIPS-based platforms should experience fewer mysterious
6055 crashes and trashed symbol tables.
6057 *** Changes in GDB-4.4:
6059 * New machines supported (host and target)
6061 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6063 BSD Reno on Vax vax-dec-bsd
6064 Ultrix on Vax vax-dec-ultrix
6066 * New machines supported (target)
6068 AMD 29000 embedded, using EBMON a29k-none-none
6072 GDB continues to improve its handling of C++. `References' work better.
6073 The demangler has also been improved, and now deals with symbols mangled as
6074 per the Annotated C++ Reference Guide.
6076 GDB also now handles `stabs' symbol information embedded in MIPS
6077 `ecoff' symbol tables. Since the ecoff format was not easily
6078 extensible to handle new languages such as C++, this appeared to be a
6079 good way to put C++ debugging info into MIPS binaries. This option
6080 will be supported in the GNU C compiler, version 2, when it is
6083 * New features for SVR4
6085 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6086 shared libraries. Debugging dynamically linked programs should present
6087 only minor differences from debugging statically linked programs.
6089 The `info proc' command will print out information about any process
6090 on an SVR4 system (including the one you are debugging). At the moment,
6091 it prints the address mappings of the process.
6093 If you bring up GDB on another SVR4 system, please send mail to
6094 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6096 * Better dynamic linking support in SunOS
6098 Reading symbols from shared libraries which contain debugging symbols
6099 now works properly. However, there remain issues such as automatic
6100 skipping of `transfer vector' code during function calls, which
6101 make it harder to debug code in a shared library, than to debug the
6102 same code linked statically.
6106 GDB is now using the latest `getopt' routines from the FSF. This
6107 version accepts the -- prefix for options with long names. GDB will
6108 continue to accept the old forms (-option and +option) as well.
6109 Various single letter abbreviations for options have been explicity
6110 added to the option table so that they won't get overshadowed in the
6111 future by other options that begin with the same letter.
6115 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6116 Many assorted bugs have been handled. Many more remain to be handled.
6117 See the various ChangeLog files (primarily in gdb and bfd) for details.
6120 *** Changes in GDB-4.3:
6122 * New machines supported (host and target)
6124 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6125 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6126 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6128 * Almost SCO Unix support
6130 We had hoped to support:
6131 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6132 (except for core file support), but we discovered very late in the release
6133 that it has problems with process groups that render gdb unusable. Sorry
6134 about that. I encourage people to fix it and post the fixes.
6136 * Preliminary ELF and DWARF support
6138 GDB can read ELF object files on System V Release 4, and can handle
6139 debugging records for C, in DWARF format, in ELF files. This support
6140 is preliminary. If you bring up GDB on another SVR4 system, please
6141 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6146 GDB now uses the latest `readline' library. One user-visible change
6147 is that two tabs will list possible command completions, which previously
6148 required typing M-? (meta-question mark, or ESC ?).
6152 The `stepi' bug that many of you noticed has been squashed.
6153 Many bugs in C++ have been handled. Many more remain to be handled.
6154 See the various ChangeLog files (primarily in gdb and bfd) for details.
6156 * State of the MIPS world (in case you wondered):
6158 GDB can understand the symbol tables emitted by the compilers
6159 supplied by most vendors of MIPS-based machines, including DEC. These
6160 symbol tables are in a format that essentially nobody else uses.
6162 Some versions of gcc come with an assembler post-processor called
6163 mips-tfile. This program is required if you want to do source-level
6164 debugging of gcc-compiled programs. I believe FSF does not ship
6165 mips-tfile with gcc version 1, but it will eventually come with gcc
6168 Debugging of g++ output remains a problem. g++ version 1.xx does not
6169 really support it at all. (If you're lucky, you should be able to get
6170 line numbers and stack traces to work, but no parameters or local
6171 variables.) With some work it should be possible to improve the
6174 When gcc version 2 is released, you will have somewhat better luck.
6175 However, even then you will get confusing results for inheritance and
6178 We will eventually provide full debugging of g++ output on
6179 DECstations. This will probably involve some kind of stabs-in-ecoff
6180 encapulation, but the details have not been worked out yet.
6183 *** Changes in GDB-4.2:
6185 * Improved configuration
6187 Only one copy of `configure' exists now, and it is not self-modifying.
6188 Porting BFD is simpler.
6192 The `step' and `next' commands now only stop at the first instruction
6193 of a source line. This prevents the multiple stops that used to occur
6194 in switch statements, for-loops, etc. `Step' continues to stop if a
6195 function that has debugging information is called within the line.
6199 Lots of small bugs fixed. More remain.
6201 * New host supported (not target)
6203 Intel 386 PC clone running Mach i386-none-mach
6206 *** Changes in GDB-4.1:
6208 * Multiple source language support
6210 GDB now has internal scaffolding to handle several source languages.
6211 It determines the type of each source file from its filename extension,
6212 and will switch expression parsing and number formatting to match the
6213 language of the function in the currently selected stack frame.
6214 You can also specifically set the language to be used, with
6215 `set language c' or `set language modula-2'.
6219 GDB now has preliminary support for the GNU Modula-2 compiler,
6220 currently under development at the State University of New York at
6221 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6222 continue through the fall of 1991 and into 1992.
6224 Other Modula-2 compilers are currently not supported, and attempting to
6225 debug programs compiled with them will likely result in an error as the
6226 symbol table is read. Feel free to work on it, though!
6228 There are hooks in GDB for strict type checking and range checking,
6229 in the `Modula-2 philosophy', but they do not currently work.
6233 GDB can now write to executable and core files (e.g. patch
6234 a variable's value). You must turn this switch on, specify
6235 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6236 by assigning a new value to a variable. Modifications take
6239 * Automatic SunOS shared library reading
6241 When you run your program, GDB automatically determines where its
6242 shared libraries (if any) have been loaded, and reads their symbols.
6243 The `share' command is no longer needed. This also works when
6244 examining core files.
6248 You can specify the number of lines that the `list' command shows.
6251 * New machines supported (host and target)
6253 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6254 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6255 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6257 * New hosts supported (not targets)
6259 IBM RT/PC: romp-ibm-aix or rtpc
6261 * New targets supported (not hosts)
6263 AMD 29000 embedded with COFF a29k-none-coff
6264 AMD 29000 embedded with a.out a29k-none-aout
6265 Ultracomputer remote kernel debug a29k-nyu-kern
6267 * New remote interfaces
6273 *** Changes in GDB-4.0:
6277 Wide output is wrapped at good places to make the output more readable.
6279 Gdb now supports cross-debugging from a host machine of one type to a
6280 target machine of another type. Communication with the target system
6281 is over serial lines. The ``target'' command handles connecting to the
6282 remote system; the ``load'' command will download a program into the
6283 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6284 also supports debugging of realtime processes running under VxWorks,
6285 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6286 stub on the target system.
6288 New CPUs supported include the AMD 29000 and Intel 960.
6290 GDB now reads object files and symbol tables via a ``binary file''
6291 library, which allows a single copy of GDB to debug programs of multiple
6292 object file types such as a.out and coff.
6294 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6295 refcard.dvi and refcard.ps are available to format it).
6298 * Control-Variable user interface simplified
6300 All variables that control the operation of the debugger can be set
6301 by the ``set'' command, and displayed by the ``show'' command.
6303 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6304 ``Show prompt'' produces the response:
6305 Gdb's prompt is new-gdb=>.
6307 What follows are the NEW set commands. The command ``help set'' will
6308 print a complete list of old and new set commands. ``help set FOO''
6309 will give a longer description of the variable FOO. ``show'' will show
6310 all of the variable descriptions and their current settings.
6312 confirm on/off: Enables warning questions for operations that are
6313 hard to recover from, e.g. rerunning the program while
6314 it is already running. Default is ON.
6316 editing on/off: Enables EMACS style command line editing
6317 of input. Previous lines can be recalled with
6318 control-P, the current line can be edited with control-B,
6319 you can search for commands with control-R, etc.
6322 history filename NAME: NAME is where the gdb command history
6323 will be stored. The default is .gdb_history,
6324 or the value of the environment variable
6327 history size N: The size, in commands, of the command history. The
6328 default is 256, or the value of the environment variable
6331 history save on/off: If this value is set to ON, the history file will
6332 be saved after exiting gdb. If set to OFF, the
6333 file will not be saved. The default is OFF.
6335 history expansion on/off: If this value is set to ON, then csh-like
6336 history expansion will be performed on
6337 command line input. The default is OFF.
6339 radix N: Sets the default radix for input and output. It can be set
6340 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6341 in the current radix, so "set radix 10" is always a no-op.
6343 height N: This integer value is the number of lines on a page. Default
6344 is 24, the current `stty rows'' setting, or the ``li#''
6345 setting from the termcap entry matching the environment
6348 width N: This integer value is the number of characters on a line.
6349 Default is 80, the current `stty cols'' setting, or the ``co#''
6350 setting from the termcap entry matching the environment
6353 Note: ``set screensize'' is obsolete. Use ``set height'' and
6354 ``set width'' instead.
6356 print address on/off: Print memory addresses in various command displays,
6357 such as stack traces and structure values. Gdb looks
6358 more ``symbolic'' if you turn this off; it looks more
6359 ``machine level'' with it on. Default is ON.
6361 print array on/off: Prettyprint arrays. New convenient format! Default
6364 print demangle on/off: Print C++ symbols in "source" form if on,
6367 print asm-demangle on/off: Same, for assembler level printouts
6370 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6373 * Support for Epoch Environment.
6375 The epoch environment is a version of Emacs v18 with windowing. One
6376 new command, ``inspect'', is identical to ``print'', except that if you
6377 are running in the epoch environment, the value is printed in its own
6381 * Support for Shared Libraries
6383 GDB can now debug programs and core files that use SunOS shared libraries.
6384 Symbols from a shared library cannot be referenced
6385 before the shared library has been linked with the program (this
6386 happens after you type ``run'' and before the function main() is entered).
6387 At any time after this linking (including when examining core files
6388 from dynamically linked programs), gdb reads the symbols from each
6389 shared library when you type the ``sharedlibrary'' command.
6390 It can be abbreviated ``share''.
6392 sharedlibrary REGEXP: Load shared object library symbols for files
6393 matching a unix regular expression. No argument
6394 indicates to load symbols for all shared libraries.
6396 info sharedlibrary: Status of loaded shared libraries.
6401 A watchpoint stops execution of a program whenever the value of an
6402 expression changes. Checking for this slows down execution
6403 tremendously whenever you are in the scope of the expression, but is
6404 quite useful for catching tough ``bit-spreader'' or pointer misuse
6405 problems. Some machines such as the 386 have hardware for doing this
6406 more quickly, and future versions of gdb will use this hardware.
6408 watch EXP: Set a watchpoint (breakpoint) for an expression.
6410 info watchpoints: Information about your watchpoints.
6412 delete N: Deletes watchpoint number N (same as breakpoints).
6413 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6414 enable N: Re-enables watchpoint number N (same as breakpoints).
6417 * C++ multiple inheritance
6419 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6422 * C++ exception handling
6424 Gdb now supports limited C++ exception handling. Besides the existing
6425 ability to breakpoint on an exception handler, gdb can breakpoint on
6426 the raising of an exception (before the stack is peeled back to the
6429 catch FOO: If there is a FOO exception handler in the dynamic scope,
6430 set a breakpoint to catch exceptions which may be raised there.
6431 Multiple exceptions (``catch foo bar baz'') may be caught.
6433 info catch: Lists all exceptions which may be caught in the
6434 current stack frame.
6437 * Minor command changes
6439 The command ``call func (arg, arg, ...)'' now acts like the print
6440 command, except it does not print or save a value if the function's result
6441 is void. This is similar to dbx usage.
6443 The ``up'' and ``down'' commands now always print the frame they end up
6444 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6445 frames without printing.
6447 * New directory command
6449 'dir' now adds directories to the FRONT of the source search path.
6450 The path starts off empty. Source files that contain debug information
6451 about the directory in which they were compiled can be found even
6452 with an empty path; Sun CC and GCC include this information. If GDB can't
6453 find your source file in the current directory, type "dir .".
6455 * Configuring GDB for compilation
6457 For normal use, type ``./configure host''. See README or gdb.texinfo
6460 GDB now handles cross debugging. If you are remotely debugging between
6461 two different machines, type ``./configure host -target=targ''.
6462 Host is the machine where GDB will run; targ is the machine
6463 where the program that you are debugging will run.