1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.12
6 *** Changes in GDB 7.12
8 * GDBserver now supports recording btrace without maintaining an active
11 * GDB now supports a negative repeat count in the 'x' command to examine
12 memory backward from the given address. For example:
15 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
16 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
17 (gdb) x/-5i 0x0000000000400580
18 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
19 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
20 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
21 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
22 0x40057b <main(int, char**)+25>:
23 callq 0x400536 <Func1(int, char const*)>
25 * Fortran: Support structures with fields of dynamic types and
26 arrays of dynamic types.
28 * GDB now supports multibit bitfields and enums in target register
31 * New Python-based convenience function $_as_string(val), which returns
32 the textual representation of a value. This function is especially
33 useful to obtain the text label of an enum value.
35 * Intel MPX bound violation handling.
37 Segmentation faults caused by a Intel MPX boundary violation
38 now display the kind of violation (upper or lower), the memory
39 address accessed and the memory bounds, along with the usual
40 signal received and code location.
44 Program received signal SIGSEGV, Segmentation fault
45 Upper bound violation while accessing address 0x7fffffffc3b3
46 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
47 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
49 * Rust language support.
50 GDB now supports debugging programs written in the Rust programming
51 language. See https://www.rust-lang.org/ for more information about
54 * Support for running interpreters on specified input/output devices
56 GDB now supports a new mechanism that allows frontends to provide
57 fully featured GDB console views, as a better alternative to
58 building such views on top of the "-interpreter-exec console"
59 command. See the new "new-ui" command below. With that command,
60 frontends can now start GDB in the traditional command-line mode
61 running in an embedded terminal emulator widget, and create a
62 separate MI interpreter running on a specified i/o device. In this
63 way, GDB handles line editing, history, tab completion, etc. in the
64 console all by itself, and the GUI uses the separate MI interpreter
65 for its own control and synchronization, invisible to the command
68 * The "catch syscall" command catches groups of related syscalls.
70 The "catch syscall" command now supports catching a group of related
71 syscalls using the 'group:' or 'g:' prefix.
76 skip -gfile file-glob-pattern
77 skip -function function
78 skip -rfunction regular-expression
79 A generalized form of the skip command, with new support for
80 glob-style file names and regular expressions for function names.
81 Additionally, a file spec and a function spec may now be combined.
83 maint info line-table REGEXP
84 Display the contents of GDB's internal line table data struture.
87 Run any GDB unit tests that were compiled in.
90 Start a new user interface instance running INTERP as interpreter,
91 using the TTY file for input/output.
95 ** gdb.Breakpoint objects have a new attribute "pending", which
96 indicates whether the breakpoint is pending.
99 Signal ("set") the given MS-Windows event object. This is used in
100 conjunction with the Windows JIT debugging (AeDebug) support, where
101 the OS suspends a crashing process until a debugger can attach to
102 it. Resuming the crashing process, in order to debug it, is done by
105 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
106 was added in GDBserver, including JIT compiling fast tracepoint's
107 conditional expression bytecode into native code.
109 * Support for various remote target protocols and ROM monitors has
112 target m32rsdi Remote M32R debugging over SDI
113 target mips MIPS remote debugging protocol
114 target pmon PMON ROM monitor
115 target ddb NEC's DDB variant of PMON for Vr4300
116 target rockhopper NEC RockHopper variant of PMON
117 target lsi LSI variant of PMO
119 * Support for tracepoints and fast tracepoints on powerpc-linux,
120 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
121 including JIT compiling fast tracepoint's conditional expression
122 bytecode into native code.
124 * MI async record =record-started now includes the method and format used for
125 recording. For example:
127 =record-started,thread-group="i1",method="btrace",format="bts"
131 Andes NDS32 nds32*-*-elf
133 *** Changes in GDB 7.11
135 * GDB now supports debugging kernel-based threads on FreeBSD.
137 * Per-inferior thread numbers
139 Thread numbers are now per inferior instead of global. If you're
140 debugging multiple inferiors, GDB displays thread IDs using a
141 qualified INF_NUM.THR_NUM form. For example:
145 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
146 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
147 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
148 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
150 As consequence, thread numbers as visible in the $_thread
151 convenience variable and in Python's InferiorThread.num attribute
152 are no longer unique between inferiors.
154 GDB now maintains a second thread ID per thread, referred to as the
155 global thread ID, which is the new equivalent of thread numbers in
156 previous releases. See also $_gthread below.
158 For backwards compatibility, MI's thread IDs always refer to global
161 * Commands that accept thread IDs now accept the qualified
162 INF_NUM.THR_NUM form as well. For example:
165 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
168 * In commands that accept a list of thread IDs, you can now refer to
169 all threads of an inferior using a star wildcard. GDB accepts
170 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
171 refer to all threads of the current inferior. For example, "info
174 * You can use "info threads -gid" to display the global thread ID of
177 * The new convenience variable $_gthread holds the global number of
180 * The new convenience variable $_inferior holds the number of the
183 * GDB now displays the ID and name of the thread that hit a breakpoint
184 or received a signal, if your program is multi-threaded. For
187 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
188 Thread 1 "main" received signal SIGINT, Interrupt.
190 * Record btrace now supports non-stop mode.
192 * Support for tracepoints on aarch64-linux was added in GDBserver.
194 * The 'record instruction-history' command now indicates speculative execution
195 when using the Intel Processor Trace recording format.
197 * GDB now allows users to specify explicit locations, bypassing
198 the linespec parser. This feature is also available to GDB/MI
201 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
202 GDB now is able to debug both AArch64 applications and ARM applications
205 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
206 including JIT compiling fast tracepoint's conditional expression bytecode
209 * GDB now supports displaced stepping on AArch64 GNU/Linux.
211 * "info threads", "info inferiors", "info display", "info checkpoints"
212 and "maint info program-spaces" now list the corresponding items in
213 ascending ID order, for consistency with all other "info" commands.
215 * In Ada, the overloads selection menu has been enhanced to display the
216 parameter types and the return types for the matching overloaded subprograms.
220 maint set target-non-stop (on|off|auto)
221 maint show target-non-stop
222 Control whether GDB targets always operate in non-stop mode even if
223 "set non-stop" is "off". The default is "auto", meaning non-stop
224 mode is enabled if supported by the target.
226 maint set bfd-sharing
227 maint show bfd-sharing
228 Control the reuse of bfd objects.
232 Control display of debugging info regarding bfd caching.
236 Control display of debugging info regarding FreeBSD threads.
238 set remote multiprocess-extensions-packet
239 show remote multiprocess-extensions-packet
240 Set/show the use of the remote protocol multiprocess extensions.
242 set remote thread-events
243 show remote thread-events
244 Set/show the use of thread create/exit events.
246 set ada print-signatures on|off
247 show ada print-signatures"
248 Control whether parameter types and return types are displayed in overloads
249 selection menus. It is activaled (@code{on}) by default.
253 Controls the maximum size of memory, in bytes, that GDB will
254 allocate for value contents. Prevents incorrect programs from
255 causing GDB to allocate overly large buffers. Default is 64k.
257 * The "disassemble" command accepts a new modifier: /s.
258 It prints mixed source+disassembly like /m with two differences:
259 - disassembled instructions are now printed in program order, and
260 - and source for all relevant files is now printed.
261 The "/m" option is now considered deprecated: its "source-centric"
262 output hasn't proved useful in practice.
264 * The "record instruction-history" command accepts a new modifier: /s.
265 It behaves exactly like /m and prints mixed source+disassembly.
267 * The "set scheduler-locking" command supports a new mode "replay".
268 It behaves like "off" in record mode and like "on" in replay mode.
270 * Support for various ROM monitors has been removed:
272 target dbug dBUG ROM monitor for Motorola ColdFire
273 target picobug Motorola picobug monitor
274 target dink32 DINK32 ROM monitor for PowerPC
275 target m32r Renesas M32R/D ROM monitor
276 target mon2000 mon2000 ROM monitor
277 target ppcbug PPCBUG ROM monitor for PowerPC
279 * Support for reading/writing memory and extracting values on architectures
280 whose memory is addressable in units of any integral multiple of 8 bits.
285 Indicates that an exec system call was executed.
287 exec-events feature in qSupported
288 The qSupported packet allows GDB to request support for exec
289 events using the new 'gdbfeature' exec-event, and the qSupported
290 response can contain the corresponding 'stubfeature'. Set and
291 show commands can be used to display whether these features are enabled.
294 Equivalent to interrupting with the ^C character, but works in
297 thread created stop reason (T05 create:...)
298 Indicates that the thread was just created and is stopped at entry.
300 thread exit stop reply (w exitcode;tid)
301 Indicates that the thread has terminated.
304 Enables/disables thread create and exit event reporting. For
305 example, this is used in non-stop mode when GDB stops a set of
306 threads and synchronously waits for the their corresponding stop
307 replies. Without exit events, if one of the threads exits, GDB
308 would hang forever not knowing that it should no longer expect a
309 stop for that same thread.
312 Indicates that there are no resumed threads left in the target (all
313 threads are stopped). The remote stub reports support for this stop
314 reply to GDB's qSupported query.
317 Enables/disables catching syscalls from the inferior process.
318 The remote stub reports support for this packet to GDB's qSupported query.
320 syscall_entry stop reason
321 Indicates that a syscall was just called.
323 syscall_return stop reason
324 Indicates that a syscall just returned.
326 * Extended-remote exec events
328 ** GDB now has support for exec events on extended-remote Linux targets.
329 For such targets with Linux kernels 2.5.46 and later, this enables
330 follow-exec-mode and exec catchpoints.
332 set remote exec-event-feature-packet
333 show remote exec-event-feature-packet
334 Set/show the use of the remote exec event feature.
336 * Thread names in remote protocol
338 The reply to qXfer:threads:read may now include a name attribute for each
341 * Target remote mode fork and exec events
343 ** GDB now has support for fork and exec events on target remote mode
344 Linux targets. For such targets with Linux kernels 2.5.46 and later,
345 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
346 fork and exec catchpoints.
348 * Remote syscall events
350 ** GDB now has support for catch syscall on remote Linux targets,
351 currently enabled on x86/x86_64 architectures.
353 set remote catch-syscall-packet
354 show remote catch-syscall-packet
355 Set/show the use of the remote catch syscall feature.
359 ** The -var-set-format command now accepts the zero-hexadecimal
360 format. It outputs data in hexadecimal format with zero-padding on the
365 ** gdb.InferiorThread objects have a new attribute "global_num",
366 which refers to the thread's global thread ID. The existing
367 "num" attribute now refers to the thread's per-inferior number.
368 See "Per-inferior thread numbers" above.
369 ** gdb.InferiorThread objects have a new attribute "inferior", which
370 is the Inferior object the thread belongs to.
372 *** Changes in GDB 7.10
374 * Support for process record-replay and reverse debugging on aarch64*-linux*
375 targets has been added. GDB now supports recording of A64 instruction set
376 including advance SIMD instructions.
378 * Support for Sun's version of the "stabs" debug file format has been removed.
380 * GDB now honors the content of the file /proc/PID/coredump_filter
381 (PID is the process ID) on GNU/Linux systems. This file can be used
382 to specify the types of memory mappings that will be included in a
383 corefile. For more information, please refer to the manual page of
384 "core(5)". GDB also has a new command: "set use-coredump-filter
385 on|off". It allows to set whether GDB will read the content of the
386 /proc/PID/coredump_filter file when generating a corefile.
388 * The "info os" command on GNU/Linux can now display information on
390 "info os cpus" Listing of all cpus/cores on the system
392 * GDB has two new commands: "set serial parity odd|even|none" and
393 "show serial parity". These allows to set or show parity for the
396 * The "info source" command now displays the producer string if it was
397 present in the debug info. This typically includes the compiler version
398 and may include things like its command line arguments.
400 * The "info dll", an alias of the "info sharedlibrary" command,
401 is now available on all platforms.
403 * Directory names supplied to the "set sysroot" commands may be
404 prefixed with "target:" to tell GDB to access shared libraries from
405 the target system, be it local or remote. This replaces the prefix
406 "remote:". The default sysroot has been changed from "" to
407 "target:". "remote:" is automatically converted to "target:" for
408 backward compatibility.
410 * The system root specified by "set sysroot" will be prepended to the
411 filename of the main executable (if reported to GDB as absolute by
412 the operating system) when starting processes remotely, and when
413 attaching to already-running local or remote processes.
415 * GDB now supports automatic location and retrieval of executable
416 files from remote targets. Remote debugging can now be initiated
417 using only a "target remote" or "target extended-remote" command
418 (no "set sysroot" or "file" commands are required). See "New remote
421 * The "dump" command now supports verilog hex format.
423 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
425 * On GNU/Linux, GDB and gdbserver are now able to access executable
426 and shared library files without a "set sysroot" command when
427 attaching to processes running in different mount namespaces from
428 the debugger. This makes it possible to attach to processes in
429 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
430 See "New remote packets" below.
432 * The "tui reg" command now provides completion for all of the
433 available register groups, including target specific groups.
435 * The HISTSIZE environment variable is no longer read when determining
436 the size of GDB's command history. GDB now instead reads the dedicated
437 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
438 disables truncation of command history. Non-numeric values of GDBHISTSIZE
443 ** Memory ports can now be unbuffered.
447 ** gdb.Objfile objects have a new attribute "username",
448 which is the name of the objfile as specified by the user,
449 without, for example, resolving symlinks.
450 ** You can now write frame unwinders in Python.
451 ** gdb.Type objects have a new method "optimized_out",
452 returning optimized out gdb.Value instance of this type.
453 ** gdb.Value objects have new methods "reference_value" and
454 "const_value" which return a reference to the value and a
455 "const" version of the value respectively.
459 maint print symbol-cache
460 Print the contents of the symbol cache.
462 maint print symbol-cache-statistics
463 Print statistics of symbol cache usage.
465 maint flush-symbol-cache
466 Flush the contents of the symbol cache.
470 Start branch trace recording using Branch Trace Store (BTS) format.
473 Evaluate expression by using the compiler and print result.
477 Explicit commands for enabling and disabling tui mode.
480 set mpx bound on i386 and amd64
481 Support for bound table investigation on Intel MPX enabled applications.
485 Start branch trace recording using Intel Processor Trace format.
488 Print information about branch tracing internals.
490 maint btrace packet-history
491 Print the raw branch tracing data.
493 maint btrace clear-packet-history
494 Discard the stored raw branch tracing data.
497 Discard all branch tracing data. It will be fetched and processed
498 anew by the next "record" command.
503 Renamed from "set debug dwarf2-die".
505 Renamed from "show debug dwarf2-die".
508 Renamed from "set debug dwarf2-read".
509 show debug dwarf-read
510 Renamed from "show debug dwarf2-read".
512 maint set dwarf always-disassemble
513 Renamed from "maint set dwarf2 always-disassemble".
514 maint show dwarf always-disassemble
515 Renamed from "maint show dwarf2 always-disassemble".
517 maint set dwarf max-cache-age
518 Renamed from "maint set dwarf2 max-cache-age".
519 maint show dwarf max-cache-age
520 Renamed from "maint show dwarf2 max-cache-age".
523 show debug dwarf-line
524 Control display of debugging info regarding DWARF line processing.
528 Set the maximum number of candidates to be considered during
529 completion. The default value is 200. This limit allows GDB
530 to avoid generating large completion lists, the computation of
531 which can cause the debugger to become temporarily unresponsive.
533 set history remove-duplicates
534 show history remove-duplicates
535 Control the removal of duplicate history entries.
537 maint set symbol-cache-size
538 maint show symbol-cache-size
539 Control the size of the symbol cache.
541 set|show record btrace bts buffer-size
542 Set and show the size of the ring buffer used for branch tracing in
544 The obtained size may differ from the requested size. Use "info
545 record" to see the obtained buffer size.
547 set debug linux-namespaces
548 show debug linux-namespaces
549 Control display of debugging info regarding Linux namespaces.
551 set|show record btrace pt buffer-size
552 Set and show the size of the ring buffer used for branch tracing in
553 Intel Processor Trace format.
554 The obtained size may differ from the requested size. Use "info
555 record" to see the obtained buffer size.
557 maint set|show btrace pt skip-pad
558 Set and show whether PAD packets are skipped when computing the
561 * The command 'thread apply all' can now support new option '-ascending'
562 to call its specified command for all threads in ascending order.
564 * Python/Guile scripting
566 ** GDB now supports auto-loading of Python/Guile scripts contained in the
567 special section named `.debug_gdb_scripts'.
571 qXfer:btrace-conf:read
572 Return the branch trace configuration for the current thread.
574 Qbtrace-conf:bts:size
575 Set the requested ring buffer size for branch tracing in BTS format.
578 Enable Intel Procesor Trace-based branch tracing for the current
579 process. The remote stub reports support for this packet to GDB's
583 Set the requested ring buffer size for branch tracing in Intel Processor
587 Indicates a memory breakpoint instruction was executed, irrespective
588 of whether it was GDB that planted the breakpoint or the breakpoint
589 is hardcoded in the program. This is required for correct non-stop
593 Indicates the target stopped for a hardware breakpoint. This is
594 required for correct non-stop mode operation.
597 Return information about files on the remote system.
600 Return the full absolute name of the file that was executed to
601 create a process running on the remote system.
604 Select the filesystem on which vFile: operations with filename
605 arguments will operate. This is required for GDB to be able to
606 access files on remote targets where the remote stub does not
607 share a common filesystem with the inferior(s).
610 Indicates that a fork system call was executed.
613 Indicates that a vfork system call was executed.
615 vforkdone stop reason
616 Indicates that a vfork child of the specified process has executed
617 an exec or exit, allowing the vfork parent to resume execution.
619 fork-events and vfork-events features in qSupported
620 The qSupported packet allows GDB to request support for fork and
621 vfork events using new 'gdbfeatures' fork-events and vfork-events,
622 and the qSupported response can contain the corresponding
623 'stubfeatures'. Set and show commands can be used to display
624 whether these features are enabled.
626 * Extended-remote fork events
628 ** GDB now has support for fork events on extended-remote Linux
629 targets. For targets with Linux kernels 2.5.60 and later, this
630 enables follow-fork-mode and detach-on-fork for both fork and
631 vfork, as well as fork and vfork catchpoints.
633 * The info record command now shows the recording format and the
634 branch tracing configuration for the current thread when using
635 the btrace record target.
636 For the BTS format, it shows the ring buffer size.
638 * GDB now has support for DTrace USDT (Userland Static Defined
639 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
641 * GDB now supports access to vector registers on S/390 GNU/Linux
644 * Removed command line options
646 -xdb HP-UX XDB compatibility mode.
648 * Removed targets and native configurations
650 HP/PA running HP-UX hppa*-*-hpux*
651 Itanium running HP-UX ia64-*-hpux*
653 * New configure options
656 This configure option allows the user to build GDB with support for
657 Intel Processor Trace (default: auto). This requires libipt.
659 --with-libipt-prefix=PATH
660 Specify the path to the version of libipt that GDB should use.
661 $PATH/include should contain the intel-pt.h header and
662 $PATH/lib should contain the libipt.so library.
664 *** Changes in GDB 7.9.1
668 ** Xmethods can now specify a result type.
670 *** Changes in GDB 7.9
672 * GDB now supports hardware watchpoints on x86 GNU Hurd.
676 ** You can now access frame registers from Python scripts.
677 ** New attribute 'producer' for gdb.Symtab objects.
678 ** gdb.Objfile objects have a new attribute "progspace",
679 which is the gdb.Progspace object of the containing program space.
680 ** gdb.Objfile objects have a new attribute "owner".
681 ** gdb.Objfile objects have a new attribute "build_id",
682 which is the build ID generated when the file was built.
683 ** gdb.Objfile objects have a new method "add_separate_debug_file".
684 ** A new event "gdb.clear_objfiles" has been added, triggered when
685 selecting a new file to debug.
686 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
687 ** New function gdb.lookup_objfile.
689 New events which are triggered when GDB modifies the state of the
692 ** gdb.events.inferior_call_pre: Function call is about to be made.
693 ** gdb.events.inferior_call_post: Function call has just been made.
694 ** gdb.events.memory_changed: A memory location has been altered.
695 ** gdb.events.register_changed: A register has been altered.
697 * New Python-based convenience functions:
699 ** $_caller_is(name [, number_of_frames])
700 ** $_caller_matches(regexp [, number_of_frames])
701 ** $_any_caller_is(name [, number_of_frames])
702 ** $_any_caller_matches(regexp [, number_of_frames])
704 * GDB now supports the compilation and injection of source code into
705 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
706 to compile the source code to object code, and if successful, inject
707 and execute that code within the current context of the inferior.
708 Currently the C language is supported. The commands used to
709 interface with this new feature are:
711 compile code [-raw|-r] [--] [source code]
712 compile file [-raw|-r] filename
716 demangle [-l language] [--] name
717 Demangle "name" in the specified language, or the current language
718 if elided. This command is renamed from the "maint demangle" command.
719 The latter is kept as a no-op to avoid "maint demangle" being interpreted
720 as "maint demangler-warning".
722 queue-signal signal-name-or-number
723 Queue a signal to be delivered to the thread when it is resumed.
725 add-auto-load-scripts-directory directory
726 Add entries to the list of directories from which to load auto-loaded
729 maint print user-registers
730 List all currently available "user" registers.
732 compile code [-r|-raw] [--] [source code]
733 Compile, inject, and execute in the inferior the executable object
734 code produced by compiling the provided source code.
736 compile file [-r|-raw] filename
737 Compile and inject into the inferior the executable object code
738 produced by compiling the source code stored in the filename
741 * On resume, GDB now always passes the signal the program had stopped
742 for to the thread the signal was sent to, even if the user changed
743 threads before resuming. Previously GDB would often (but not
744 always) deliver the signal to the thread that happens to be current
747 * Conversely, the "signal" command now consistently delivers the
748 requested signal to the current thread. GDB now asks for
749 confirmation if the program had stopped for a signal and the user
750 switched threads meanwhile.
752 * "breakpoint always-inserted" modes "off" and "auto" merged.
754 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
755 won't remove breakpoints from the target until all threads stop,
756 even in non-stop mode. The "auto" mode has been removed, and "off"
757 is now the default mode.
761 set debug symbol-lookup
762 show debug symbol-lookup
763 Control display of debugging info regarding symbol lookup.
767 ** The -list-thread-groups command outputs an exit-code field for
768 inferiors that have exited.
772 MIPS SDE mips*-sde*-elf*
776 Support for these obsolete configurations has been removed.
778 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
779 SGI Irix-5.x mips-*-irix5*
780 SGI Irix-6.x mips-*-irix6*
781 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
782 VAX running Ultrix vax-*-ultrix*
784 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
785 and "assf"), have been removed. Use the "sharedlibrary" command, or
786 its alias "share", instead.
788 *** Changes in GDB 7.8
790 * New command line options
793 This is an alias for the --data-directory option.
795 * GDB supports printing and modifying of variable length automatic arrays
796 as specified in ISO C99.
798 * The ARM simulator now supports instruction level tracing
799 with or without disassembly.
803 GDB now has support for scripting using Guile. Whether this is
804 available is determined at configure time.
805 Guile version 2.0 or greater is required.
806 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
808 * New commands (for set/show, see "New options" below)
812 Invoke CODE by passing it to the Guile interpreter.
816 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
818 info auto-load guile-scripts [regexp]
819 Print the list of automatically loaded Guile scripts.
821 * The source command is now capable of sourcing Guile scripts.
822 This feature is dependent on the debugger being built with Guile support.
826 set print symbol-loading (off|brief|full)
827 show print symbol-loading
828 Control whether to print informational messages when loading symbol
829 information for a file. The default is "full", but when debugging
830 programs with large numbers of shared libraries the amount of output
833 set guile print-stack (none|message|full)
834 show guile print-stack
835 Show a stack trace when an error is encountered in a Guile script.
837 set auto-load guile-scripts (on|off)
838 show auto-load guile-scripts
839 Control auto-loading of Guile script files.
841 maint ada set ignore-descriptive-types (on|off)
842 maint ada show ignore-descriptive-types
843 Control whether the debugger should ignore descriptive types in Ada
844 programs. The default is not to ignore the descriptive types. See
845 the user manual for more details on descriptive types and the intended
846 usage of this option.
848 set auto-connect-native-target
850 Control whether GDB is allowed to automatically connect to the
851 native target for the run, attach, etc. commands when not connected
852 to any target yet. See also "target native" below.
854 set record btrace replay-memory-access (read-only|read-write)
855 show record btrace replay-memory-access
856 Control what memory accesses are allowed during replay.
858 maint set target-async (on|off)
859 maint show target-async
860 This controls whether GDB targets operate in synchronous or
861 asynchronous mode. Normally the default is asynchronous, if it is
862 available; but this can be changed to more easily debug problems
863 occurring only in synchronous mode.
865 set mi-async (on|off)
867 Control whether MI asynchronous mode is preferred. This supersedes
868 "set target-async" of previous GDB versions.
870 * "set target-async" is deprecated as a CLI option and is now an alias
871 for "set mi-async" (only puts MI into async mode).
873 * Background execution commands (e.g., "c&", "s&", etc.) are now
874 possible ``out of the box'' if the target supports them. Previously
875 the user would need to explicitly enable the possibility with the
876 "set target-async on" command.
878 * New features in the GDB remote stub, GDBserver
880 ** New option --debug-format=option1[,option2,...] allows one to add
881 additional text to each output. At present only timestamps
882 are supported: --debug-format=timestamps.
883 Timestamps can also be turned on with the
884 "monitor set debug-format timestamps" command from GDB.
886 * The 'record instruction-history' command now starts counting instructions
887 at one. This also affects the instruction ranges reported by the
888 'record function-call-history' command when given the /i modifier.
890 * The command 'record function-call-history' supports a new modifier '/c' to
891 indent the function names based on their call stack depth.
892 The fields for the '/i' and '/l' modifier have been reordered.
893 The source line range is now prefixed with 'at'.
894 The instruction range is now prefixed with 'inst'.
895 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
896 "record instruction-history" and "list" commands.
898 * The ranges given as arguments to the 'record function-call-history' and
899 'record instruction-history' commands are now inclusive.
901 * The btrace record target now supports the 'record goto' command.
902 For locations inside the execution trace, the back trace is computed
903 based on the information stored in the execution trace.
905 * The btrace record target supports limited reverse execution and replay.
906 The target does not record data and therefore does not allow reading
909 * The "catch syscall" command now works on s390*-linux* targets.
911 * The "compare-sections" command is no longer specific to target
912 remote. It now works with all targets.
914 * All native targets are now consistently called "native".
915 Consequently, the "target child", "target GNU", "target djgpp",
916 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
917 commands have been replaced with "target native". The QNX/NTO port
918 leaves the "procfs" target in place and adds a "native" target for
919 consistency with other ports. The impact on users should be minimal
920 as these commands previously either throwed an error, or were
921 no-ops. The target's name is visible in the output of the following
922 commands: "help target", "info target", "info files", "maint print
925 * The "target native" command now connects to the native target. This
926 can be used to launch native programs even when "set
927 auto-connect-native-target" is set to off.
929 * GDB now supports access to Intel MPX registers on GNU/Linux.
931 * Support for Intel AVX-512 registers on GNU/Linux.
932 Support displaying and modifying Intel AVX-512 registers
933 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
937 qXfer:btrace:read's annex
938 The qXfer:btrace:read packet supports a new annex 'delta' to read
939 branch trace incrementally.
943 ** Valid Python operations on gdb.Value objects representing
944 structs/classes invoke the corresponding overloaded operators if
946 ** New `Xmethods' feature in the Python API. Xmethods are
947 additional methods or replacements for existing methods of a C++
948 class. This feature is useful for those cases where a method
949 defined in C++ source code could be inlined or optimized out by
950 the compiler, making it unavailable to GDB.
953 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
955 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
956 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
957 its alias "share", instead.
959 * The commands "set remotebaud" and "show remotebaud" are no longer
960 supported. Use "set serial baud" and "show serial baud" (respectively)
965 ** A new option "-gdb-set mi-async" replaces "-gdb-set
966 target-async". The latter is left as a deprecated alias of the
967 former for backward compatibility. If the target supports it,
968 CLI background execution commands are now always possible by
969 default, independently of whether the frontend stated a
970 preference for asynchronous execution with "-gdb-set mi-async".
971 Previously "-gdb-set target-async off" affected both MI execution
972 commands and CLI execution commands.
974 *** Changes in GDB 7.7
976 * Improved support for process record-replay and reverse debugging on
977 arm*-linux* targets. Support for thumb32 and syscall instruction
978 recording has been added.
980 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
982 * GDB now supports Fission DWP file format version 2.
983 http://gcc.gnu.org/wiki/DebugFission
985 * New convenience function "$_isvoid", to check whether an expression
986 is void. A void expression is an expression where the type of the
987 result is "void". For example, some convenience variables may be
988 "void" when evaluated (e.g., "$_exitcode" before the execution of
989 the program being debugged; or an undefined convenience variable).
990 Another example, when calling a function whose return type is
993 * The "maintenance print objfiles" command now takes an optional regexp.
995 * The "catch syscall" command now works on arm*-linux* targets.
997 * GDB now consistently shows "<not saved>" when printing values of
998 registers the debug info indicates have not been saved in the frame
999 and there's nowhere to retrieve them from
1000 (callee-saved/call-clobbered registers):
1005 (gdb) info registers rax
1008 Before, the former would print "<optimized out>", and the latter
1009 "*value not available*".
1011 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1016 ** Frame filters and frame decorators have been added.
1017 ** Temporary breakpoints are now supported.
1018 ** Line tables representation has been added.
1019 ** New attribute 'parent_type' for gdb.Field objects.
1020 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1021 ** New attribute 'name' for gdb.Type objects.
1025 Nios II ELF nios2*-*-elf
1026 Nios II GNU/Linux nios2*-*-linux
1027 Texas Instruments MSP430 msp430*-*-elf
1029 * Removed native configurations
1031 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1032 been removed. ELF variants of these configurations are kept supported.
1034 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1035 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1036 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1037 i[34567]86-*-openbsd3.[0-3]
1038 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1039 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1040 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1044 Like "catch throw", but catches a re-thrown exception.
1045 maint check-psymtabs
1046 Renamed from old "maint check-symtabs".
1048 Perform consistency checks on symtabs.
1049 maint expand-symtabs
1050 Expand symtabs matching an optional regexp.
1053 Display the details of GDB configure-time options.
1055 maint set|show per-command
1056 maint set|show per-command space
1057 maint set|show per-command time
1058 maint set|show per-command symtab
1059 Enable display of per-command gdb resource usage.
1061 remove-symbol-file FILENAME
1062 remove-symbol-file -a ADDRESS
1063 Remove a symbol file added via add-symbol-file. The file to remove
1064 can be identified by its filename or by an address that lies within
1065 the boundaries of this symbol file in memory.
1068 info exceptions REGEXP
1069 Display the list of Ada exceptions defined in the program being
1070 debugged. If provided, only the exceptions whose names match REGEXP
1075 set debug symfile off|on
1077 Control display of debugging info regarding reading symbol files and
1078 symbol tables within those files
1080 set print raw frame-arguments
1081 show print raw frame-arguments
1082 Set/show whether to print frame arguments in raw mode,
1083 disregarding any defined pretty-printers.
1085 set remote trace-status-packet
1086 show remote trace-status-packet
1087 Set/show the use of remote protocol qTStatus packet.
1091 Control display of debugging messages related to Nios II targets.
1095 Control whether target-assisted range stepping is enabled.
1097 set startup-with-shell
1098 show startup-with-shell
1099 Specifies whether Unix child processes are started via a shell or
1104 Use the target memory cache for accesses to the code segment. This
1105 improves performance of remote debugging (particularly disassembly).
1107 * You can now use a literal value 'unlimited' for options that
1108 interpret 0 or -1 as meaning "unlimited". E.g., "set
1109 trace-buffer-size unlimited" is now an alias for "set
1110 trace-buffer-size -1" and "set height unlimited" is now an alias for
1113 * The "set debug symtab-create" debugging option of GDB has been changed to
1114 accept a verbosity level. 0 means "off", 1 provides basic debugging
1115 output, and values of 2 or greater provides more verbose output.
1117 * New command-line options
1119 Display the details of GDB configure-time options.
1121 * The command 'tsave' can now support new option '-ctf' to save trace
1122 buffer in Common Trace Format.
1124 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1127 * GDB now implements the the C++ 'typeid' operator.
1129 * The new convenience variable $_exception holds the exception being
1130 thrown or caught at an exception-related catchpoint.
1132 * The exception-related catchpoints, like "catch throw", now accept a
1133 regular expression which can be used to filter exceptions by type.
1135 * The new convenience variable $_exitsignal is automatically set to
1136 the terminating signal number when the program being debugged dies
1137 due to an uncaught signal.
1141 ** All MI commands now accept an optional "--language" option.
1142 Support for this feature can be verified by using the "-list-features"
1143 command, which should contain "language-option".
1145 ** The new command -info-gdb-mi-command allows the user to determine
1146 whether a GDB/MI command is supported or not.
1148 ** The "^error" result record returned when trying to execute an undefined
1149 GDB/MI command now provides a variable named "code" whose content is the
1150 "undefined-command" error code. Support for this feature can be verified
1151 by using the "-list-features" command, which should contain
1152 "undefined-command-error-code".
1154 ** The -trace-save MI command can optionally save trace buffer in Common
1157 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1159 ** The command -data-list-register-values now accepts an optional
1160 "--skip-unavailable" option. When used, only the available registers
1163 ** The new command -trace-frame-collected dumps collected variables,
1164 computed expressions, tvars, memory and registers in a traceframe.
1166 ** The commands -stack-list-locals, -stack-list-arguments and
1167 -stack-list-variables now accept an option "--skip-unavailable".
1168 When used, only the available locals or arguments are displayed.
1170 ** The -exec-run command now accepts an optional "--start" option.
1171 When used, the command follows the same semantics as the "start"
1172 command, stopping the program's execution at the start of its
1173 main subprogram. Support for this feature can be verified using
1174 the "-list-features" command, which should contain
1175 "exec-run-start-option".
1177 ** The new commands -catch-assert and -catch-exceptions insert
1178 catchpoints stopping the program when Ada exceptions are raised.
1180 ** The new command -info-ada-exceptions provides the equivalent of
1181 the new "info exceptions" command.
1183 * New system-wide configuration scripts
1184 A GDB installation now provides scripts suitable for use as system-wide
1185 configuration scripts for the following systems:
1189 * GDB now supports target-assigned range stepping with remote targets.
1190 This improves the performance of stepping source lines by reducing
1191 the number of control packets from/to GDB. See "New remote packets"
1194 * GDB now understands the element 'tvar' in the XML traceframe info.
1195 It has the id of the collected trace state variables.
1197 * On S/390 targets that provide the transactional-execution feature,
1198 the program interruption transaction diagnostic block (TDB) is now
1199 represented as a number of additional "registers" in GDB.
1201 * New remote packets
1205 The vCont packet supports a new 'r' action, that tells the remote
1206 stub to step through an address range itself, without GDB
1207 involvemement at each single-step.
1209 qXfer:libraries-svr4:read's annex
1210 The previously unused annex of the qXfer:libraries-svr4:read packet
1211 is now used to support passing an argument list. The remote stub
1212 reports support for this argument list to GDB's qSupported query.
1213 The defined arguments are "start" and "prev", used to reduce work
1214 necessary for library list updating, resulting in significant
1217 * New features in the GDB remote stub, GDBserver
1219 ** GDBserver now supports target-assisted range stepping. Currently
1220 enabled on x86/x86_64 GNU/Linux targets.
1222 ** GDBserver now adds element 'tvar' in the XML in the reply to
1223 'qXfer:traceframe-info:read'. It has the id of the collected
1224 trace state variables.
1226 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1229 * New 'z' formatter for printing and examining memory, this displays the
1230 value as hexadecimal zero padded on the left to the size of the type.
1232 * GDB can now use Windows x64 unwinding data.
1234 * The "set remotebaud" command has been replaced by "set serial baud".
1235 Similarly, "show remotebaud" has been replaced by "show serial baud".
1236 The "set remotebaud" and "show remotebaud" commands are still available
1237 to provide backward compatibility with older versions of GDB.
1239 *** Changes in GDB 7.6
1241 * Target record has been renamed to record-full.
1242 Record/replay is now enabled with the "record full" command.
1243 This also affects settings that are associated with full record/replay
1244 that have been moved from "set/show record" to "set/show record full":
1246 set|show record full insn-number-max
1247 set|show record full stop-at-limit
1248 set|show record full memory-query
1250 * A new record target "record-btrace" has been added. The new target
1251 uses hardware support to record the control-flow of a process. It
1252 does not support replaying the execution, but it implements the
1253 below new commands for investigating the recorded execution log.
1254 This new recording method can be enabled using:
1258 The "record-btrace" target is only available on Intel Atom processors
1259 and requires a Linux kernel 2.6.32 or later.
1261 * Two new commands have been added for record/replay to give information
1262 about the recorded execution without having to replay the execution.
1263 The commands are only supported by "record btrace".
1265 record instruction-history prints the execution history at
1266 instruction granularity
1268 record function-call-history prints the execution history at
1269 function granularity
1271 * New native configurations
1273 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1274 FreeBSD/powerpc powerpc*-*-freebsd
1275 x86_64/Cygwin x86_64-*-cygwin*
1276 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1280 ARM AArch64 aarch64*-*-elf
1281 ARM AArch64 GNU/Linux aarch64*-*-linux
1282 Lynx 178 PowerPC powerpc-*-lynx*178
1283 x86_64/Cygwin x86_64-*-cygwin*
1284 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1286 * If the configured location of system.gdbinit file (as given by the
1287 --with-system-gdbinit option at configure time) is in the
1288 data-directory (as specified by --with-gdb-datadir at configure
1289 time) or in one of its subdirectories, then GDB will look for the
1290 system-wide init file in the directory specified by the
1291 --data-directory command-line option.
1293 * New command line options:
1295 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1296 other initialization files, unlike -nx which disables all of them.
1298 * Removed command line options
1300 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1303 * The 'ptype' and 'whatis' commands now accept an argument to control
1306 * 'info proc' now works on some core files.
1310 ** Vectors can be created with gdb.Type.vector.
1312 ** Python's atexit.register now works in GDB.
1314 ** Types can be pretty-printed via a Python API.
1316 ** Python 3 is now supported (in addition to Python 2.4 or later)
1318 ** New class gdb.Architecture exposes GDB's internal representation
1319 of architecture in the Python API.
1321 ** New method Frame.architecture returns the gdb.Architecture object
1322 corresponding to the frame's architecture.
1324 * New Python-based convenience functions:
1326 ** $_memeq(buf1, buf2, length)
1327 ** $_streq(str1, str2)
1329 ** $_regex(str, regex)
1331 * The 'cd' command now defaults to using '~' (the home directory) if not
1334 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1335 default for GCC since November 2000.
1337 * The command 'forward-search' can now be abbreviated as 'fo'.
1339 * The command 'info tracepoints' can now display 'installed on target'
1340 or 'not installed on target' for each non-pending location of tracepoint.
1342 * New configure options
1344 --enable-libmcheck/--disable-libmcheck
1345 By default, development versions are built with -lmcheck on hosts
1346 that support it, in order to help track memory corruption issues.
1347 Release versions, on the other hand, are built without -lmcheck
1348 by default. The --enable-libmcheck/--disable-libmcheck configure
1349 options allow the user to override that default.
1350 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1351 This configure option allows the user to build GDB with
1352 libbabeltrace using which GDB can read Common Trace Format data.
1354 * New commands (for set/show, see "New options" below)
1357 Catch signals. This is similar to "handle", but allows commands and
1358 conditions to be attached.
1361 List the BFDs known to GDB.
1363 python-interactive [command]
1365 Start a Python interactive prompt, or evaluate the optional command
1366 and print the result of expressions.
1369 "py" is a new alias for "python".
1371 enable type-printer [name]...
1372 disable type-printer [name]...
1373 Enable or disable type printers.
1377 ** For the Renesas Super-H architecture, the "regs" command has been removed
1378 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1383 set print type methods (on|off)
1384 show print type methods
1385 Control whether method declarations are displayed by "ptype".
1386 The default is to show them.
1388 set print type typedefs (on|off)
1389 show print type typedefs
1390 Control whether typedef definitions are displayed by "ptype".
1391 The default is to show them.
1393 set filename-display basename|relative|absolute
1394 show filename-display
1395 Control the way in which filenames is displayed.
1396 The default is "relative", which preserves previous behavior.
1398 set trace-buffer-size
1399 show trace-buffer-size
1400 Request target to change the size of trace buffer.
1402 set remote trace-buffer-size-packet auto|on|off
1403 show remote trace-buffer-size-packet
1404 Control the use of the remote protocol `QTBuffer:size' packet.
1408 Control display of debugging messages related to ARM AArch64.
1411 set debug coff-pe-read
1412 show debug coff-pe-read
1413 Control display of debugging messages related to reading of COFF/PE
1418 Control display of debugging messages related to Mach-O symbols
1421 set debug notification
1422 show debug notification
1423 Control display of debugging info for async remote notification.
1427 ** Command parameter changes are now notified using new async record
1428 "=cmd-param-changed".
1429 ** Trace frame changes caused by command "tfind" are now notified using
1430 new async record "=traceframe-changed".
1431 ** The creation, deletion and modification of trace state variables
1432 are now notified using new async records "=tsv-created",
1433 "=tsv-deleted" and "=tsv-modified".
1434 ** The start and stop of process record are now notified using new
1435 async record "=record-started" and "=record-stopped".
1436 ** Memory changes are now notified using new async record
1438 ** The data-disassemble command response will include a "fullname" field
1439 containing the absolute file name when source has been requested.
1440 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1441 command, to allow pattern filling of memory areas.
1442 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1443 library load/unload events.
1444 ** The response to breakpoint commands and breakpoint async records
1445 includes an "installed" field containing a boolean state about each
1446 non-pending tracepoint location is whether installed on target or not.
1447 ** Output of the "-trace-status" command includes a "trace-file" field
1448 containing the name of the trace file being examined. This field is
1449 optional, and only present when examining a trace file.
1450 ** The "fullname" field is now always present along with the "file" field,
1451 even if the file cannot be found by GDB.
1453 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1454 You must have the LZMA library available when configuring GDB for this
1455 feature to be enabled. For more information, see:
1456 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1458 * New remote packets
1461 Set the size of trace buffer. The remote stub reports support for this
1462 packet to gdb's qSupported query.
1465 Enable Branch Trace Store (BTS)-based branch tracing for the current
1466 thread. The remote stub reports support for this packet to gdb's
1470 Disable branch tracing for the current thread. The remote stub reports
1471 support for this packet to gdb's qSupported query.
1474 Read the traced branches for the current thread. The remote stub
1475 reports support for this packet to gdb's qSupported query.
1477 *** Changes in GDB 7.5
1479 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1480 for more x32 ABI info.
1482 * GDB now supports access to MIPS DSP registers on Linux targets.
1484 * GDB now supports debugging microMIPS binaries.
1486 * The "info os" command on GNU/Linux can now display information on
1487 several new classes of objects managed by the operating system:
1488 "info os procgroups" lists process groups
1489 "info os files" lists file descriptors
1490 "info os sockets" lists internet-domain sockets
1491 "info os shm" lists shared-memory regions
1492 "info os semaphores" lists semaphores
1493 "info os msg" lists message queues
1494 "info os modules" lists loaded kernel modules
1496 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1497 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1498 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1499 options and inspect the probe arguments using the new $_probe_arg family
1500 of convenience variables. You can obtain more information about SystemTap
1501 in <http://sourceware.org/systemtap/>.
1503 * GDB now supports reversible debugging on ARM, it allows you to
1504 debug basic ARM and THUMB instructions, and provides
1505 record/replay support.
1507 * The option "symbol-reloading" has been deleted as it is no longer used.
1511 ** GDB commands implemented in Python can now be put in command class
1514 ** The "maint set python print-stack on|off" is now deleted.
1516 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1517 apply "flag enum"-style pretty-printing to any enum.
1519 ** gdb.lookup_symbol can now work when there is no current frame.
1521 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1522 the source at which the symbol was defined.
1524 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1525 method 'value'. The former indicates whether the symbol needs a
1526 frame in order to compute its value, and the latter computes the
1529 ** A new method 'referenced_value' on gdb.Value objects which can
1530 dereference pointer as well as C++ reference values.
1532 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1533 which return the global and static blocks (as gdb.Block objects),
1534 of the underlying symbol table, respectively.
1536 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1537 object associated with a PC value.
1539 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1540 of the address range occupied by code for the current source line.
1542 * Go language support.
1543 GDB now supports debugging programs written in the Go programming
1546 * GDBserver now supports stdio connections.
1547 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1549 * The binary "gdbtui" can no longer be built or installed.
1550 Use "gdb -tui" instead.
1552 * GDB will now print "flag" enums specially. A flag enum is one where
1553 all the enumerator values have no bits in common when pairwise
1554 "and"ed. When printing a value whose type is a flag enum, GDB will
1555 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1556 (gdb) print (enum E) 3
1559 * The filename part of a linespec will now match trailing components
1560 of a source file name. For example, "break gcc/expr.c:1000" will
1561 now set a breakpoint in build/gcc/expr.c, but not
1562 build/libcpp/expr.c.
1564 * The "info proc" and "generate-core-file" commands will now also
1565 work on remote targets connected to GDBserver on Linux.
1567 * The command "info catch" has been removed. It has been disabled
1568 since December 2007.
1570 * The "catch exception" and "catch assert" commands now accept
1571 a condition at the end of the command, much like the "break"
1572 command does. For instance:
1574 (gdb) catch exception Constraint_Error if Barrier = True
1576 Previously, it was possible to add a condition to such catchpoints,
1577 but it had to be done as a second step, after the catchpoint had been
1578 created, using the "condition" command.
1580 * The "info static-tracepoint-marker" command will now also work on
1581 native Linux targets with in-process agent.
1583 * GDB can now set breakpoints on inlined functions.
1585 * The .gdb_index section has been updated to include symbols for
1586 inlined functions. GDB will ignore older .gdb_index sections by
1587 default, which could cause symbol files to be loaded more slowly
1588 until their .gdb_index sections can be recreated. The new command
1589 "set use-deprecated-index-sections on" will cause GDB to use any older
1590 .gdb_index sections it finds. This will restore performance, but the
1591 ability to set breakpoints on inlined functions will be lost in symbol
1592 files with older .gdb_index sections.
1594 The .gdb_index section has also been updated to record more information
1595 about each symbol. This speeds up the "info variables", "info functions"
1596 and "info types" commands when used with programs having the .gdb_index
1597 section, as well as speeding up debugging with shared libraries using
1598 the .gdb_index section.
1600 * Ada support for GDB/MI Variable Objects has been added.
1602 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1607 ** New command -info-os is the MI equivalent of "info os".
1609 ** Output logs ("set logging" and related) now include MI output.
1613 ** "set use-deprecated-index-sections on|off"
1614 "show use-deprecated-index-sections on|off"
1615 Controls the use of deprecated .gdb_index sections.
1617 ** "catch load" and "catch unload" can be used to stop when a shared
1618 library is loaded or unloaded, respectively.
1620 ** "enable count" can be used to auto-disable a breakpoint after
1623 ** "info vtbl" can be used to show the virtual method tables for
1624 C++ and Java objects.
1626 ** "explore" and its sub commands "explore value" and "explore type"
1627 can be used to recursively explore values and types of
1628 expressions. These commands are available only if GDB is
1629 configured with '--with-python'.
1631 ** "info auto-load" shows status of all kinds of auto-loaded files,
1632 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1633 sequences of commands files, "info auto-load python-scripts"
1634 shows status of auto-loading Python script files,
1635 "info auto-load local-gdbinit" shows status of loading init file
1636 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1637 status of inferior specific thread debugging shared library loading.
1639 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1640 and "show auto-load-scripts" commands have been deprecated, use their
1641 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1642 and "show auto-load python-scripts" counterparts instead.
1644 ** "dprintf location,format,args..." creates a dynamic printf, which
1645 is basically a breakpoint that does a printf and immediately
1646 resumes your program's execution, so it is like a printf that you
1647 can insert dynamically at runtime instead of at compiletime.
1649 ** "set print symbol"
1651 Controls whether GDB attempts to display the symbol, if any,
1652 corresponding to addresses it prints. This defaults to "on", but
1653 you can set it to "off" to restore GDB's previous behavior.
1655 * Deprecated commands
1657 ** For the Renesas Super-H architecture, the "regs" command has been
1658 deprecated, and "info all-registers" should be used instead.
1662 Renesas RL78 rl78-*-elf
1663 HP OpenVMS ia64 ia64-hp-openvms*
1665 * GDBserver supports evaluation of breakpoint conditions. When
1666 support is advertised by GDBserver, GDB may be told to send the
1667 breakpoint conditions in bytecode form to GDBserver. GDBserver
1668 will only report the breakpoint trigger to GDB when its condition
1673 set mips compression
1674 show mips compression
1675 Select the compressed ISA encoding used in functions that have no symbol
1676 information available. The encoding can be set to either of:
1679 and is updated automatically from ELF file flags if available.
1681 set breakpoint condition-evaluation
1682 show breakpoint condition-evaluation
1683 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1684 GDBserver ("target"). Default option "auto" chooses the most efficient
1686 This option can improve debugger efficiency depending on the speed of the
1690 Disable auto-loading globally.
1693 Show auto-loading setting of all kinds of auto-loaded files.
1695 set auto-load gdb-scripts on|off
1696 show auto-load gdb-scripts
1697 Control auto-loading of GDB canned sequences of commands files.
1699 set auto-load python-scripts on|off
1700 show auto-load python-scripts
1701 Control auto-loading of Python script files.
1703 set auto-load local-gdbinit on|off
1704 show auto-load local-gdbinit
1705 Control loading of init file (.gdbinit) from current directory.
1707 set auto-load libthread-db on|off
1708 show auto-load libthread-db
1709 Control auto-loading of inferior specific thread debugging shared library.
1711 set auto-load scripts-directory <dir1>[:<dir2>...]
1712 show auto-load scripts-directory
1713 Set a list of directories from which to load auto-loaded scripts.
1714 Automatically loaded Python scripts and GDB scripts are located in one
1715 of the directories listed by this option.
1716 The delimiter (':' above) may differ according to the host platform.
1718 set auto-load safe-path <dir1>[:<dir2>...]
1719 show auto-load safe-path
1720 Set a list of directories from which it is safe to auto-load files.
1721 The delimiter (':' above) may differ according to the host platform.
1723 set debug auto-load on|off
1724 show debug auto-load
1725 Control display of debugging info for auto-loading the files above.
1727 set dprintf-style gdb|call|agent
1729 Control the way in which a dynamic printf is performed; "gdb"
1730 requests a GDB printf command, while "call" causes dprintf to call a
1731 function in the inferior. "agent" requests that the target agent
1732 (such as GDBserver) do the printing.
1734 set dprintf-function <expr>
1735 show dprintf-function
1736 set dprintf-channel <expr>
1737 show dprintf-channel
1738 Set the function and optional first argument to the call when using
1739 the "call" style of dynamic printf.
1741 set disconnected-dprintf on|off
1742 show disconnected-dprintf
1743 Control whether agent-style dynamic printfs continue to be in effect
1744 after GDB disconnects.
1746 * New configure options
1748 --with-auto-load-dir
1749 Configure default value for the 'set auto-load scripts-directory'
1750 setting above. It defaults to '$debugdir:$datadir/auto-load',
1751 $debugdir representing global debugging info directories (available
1752 via 'show debug-file-directory') and $datadir representing GDB's data
1753 directory (available via 'show data-directory').
1755 --with-auto-load-safe-path
1756 Configure default value for the 'set auto-load safe-path' setting
1757 above. It defaults to the --with-auto-load-dir setting.
1759 --without-auto-load-safe-path
1760 Set 'set auto-load safe-path' to '/', effectively disabling this
1763 * New remote packets
1765 z0/z1 conditional breakpoints extension
1767 The z0/z1 breakpoint insertion packets have been extended to carry
1768 a list of conditional expressions over to the remote stub depending on the
1769 condition evaluation mode. The use of this extension can be controlled
1770 via the "set remote conditional-breakpoints-packet" command.
1774 Specify the signals which the remote stub may pass to the debugged
1775 program without GDB involvement.
1777 * New command line options
1779 --init-command=FILE, -ix Like --command, -x but execute it
1780 before loading inferior.
1781 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1782 execute it before loading inferior.
1784 *** Changes in GDB 7.4
1786 * GDB now handles ambiguous linespecs more consistently; the existing
1787 FILE:LINE support has been expanded to other types of linespecs. A
1788 breakpoint will now be set on all matching locations in all
1789 inferiors, and locations will be added or removed according to
1792 * GDB now allows you to skip uninteresting functions and files when
1793 stepping with the "skip function" and "skip file" commands.
1795 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1796 and "show remote hardware-watchpoint-length-limit". These allows to
1797 set or show the maximum length limit (in bytes) of a remote
1798 target hardware watchpoint.
1800 This allows e.g. to use "unlimited" hardware watchpoints with the
1801 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1802 watchpoints are slower than real hardware watchpoints but are
1803 significantly faster than gdb software watchpoints.
1807 ** The register_pretty_printer function in module gdb.printing now takes
1808 an optional `replace' argument. If True, the new printer replaces any
1811 ** The "maint set python print-stack on|off" command has been
1812 deprecated and will be deleted in GDB 7.5.
1813 A new command: "set python print-stack none|full|message" has
1814 replaced it. Additionally, the default for "print-stack" is
1815 now "message", which just prints the error message without
1818 ** A prompt substitution hook (prompt_hook) is now available to the
1821 ** A new Python module, gdb.prompt has been added to the GDB Python
1822 modules library. This module provides functionality for
1823 escape sequences in prompts (used by set/show
1824 extended-prompt). These escape sequences are replaced by their
1825 corresponding value.
1827 ** Python commands and convenience-functions located in
1828 'data-directory'/python/gdb/command and
1829 'data-directory'/python/gdb/function are now automatically loaded
1832 ** Blocks now provide four new attributes. global_block and
1833 static_block will return the global and static blocks
1834 respectively. is_static and is_global are boolean attributes
1835 that indicate if the block is one of those two types.
1837 ** Symbols now provide the "type" attribute, the type of the symbol.
1839 ** The "gdb.breakpoint" function has been deprecated in favor of
1842 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1843 of a function. This class is based on the "finish" command
1844 available in the CLI.
1846 ** Type objects for struct and union types now allow access to
1847 the fields using standard Python dictionary (mapping) methods.
1848 For example, "some_type['myfield']" now works, as does
1849 "some_type.items()".
1851 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1854 ** A new function, "deep_items" has been added to the gdb.types
1855 module in the GDB Python modules library. This function returns
1856 an iterator over the fields of a struct or union type. Unlike
1857 the standard Python "iteritems" method, it will recursively traverse
1858 any anonymous fields.
1862 ** "*stopped" events can report several new "reason"s, such as
1865 ** Breakpoint changes are now notified using new async records, like
1866 "=breakpoint-modified".
1868 ** New command -ada-task-info.
1870 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1871 $sdir specifies the default system locations of shared libraries.
1872 $pdir specifies the directory where the libpthread used by the application
1875 GDB no longer looks in $sdir and $pdir after it has searched the directories
1876 mentioned in libthread-db-search-path. If you want to search those
1877 directories, they must be specified in libthread-db-search-path.
1878 The default value of libthread-db-search-path on GNU/Linux and Solaris
1879 systems is now "$sdir:$pdir".
1881 $pdir is not supported by gdbserver, it is currently ignored.
1882 $sdir is supported by gdbserver.
1884 * New configure option --with-iconv-bin.
1885 When using the internationalization support like the one in the GNU C
1886 library, GDB will invoke the "iconv" program to get a list of supported
1887 character sets. If this program lives in a non-standard location, one can
1888 use this option to specify where to find it.
1890 * When natively debugging programs on PowerPC BookE processors running
1891 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1892 watchpoints, which specify a mask in addition to an address to watch.
1893 The mask specifies that some bits of an address (the bits which are
1894 reset in the mask) should be ignored when matching the address accessed
1895 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1896 section in the user manual for more details.
1898 * The new option --once causes GDBserver to stop listening for connections once
1899 the first connection is made. The listening port used by GDBserver will
1900 become available after that.
1902 * New commands "info macros" and "alias" have been added.
1904 * New function parameters suffix @entry specifies value of function parameter
1905 at the time the function got called. Entry values are available only since
1911 "!" is now an alias of the "shell" command.
1912 Note that no space is needed between "!" and SHELL COMMAND.
1916 watch EXPRESSION mask MASK_VALUE
1917 The watch command now supports the mask argument which allows creation
1918 of masked watchpoints, if the current architecture supports this feature.
1920 info auto-load-scripts [REGEXP]
1921 This command was formerly named "maintenance print section-scripts".
1922 It is now generally useful and is no longer a maintenance-only command.
1924 info macro [-all] [--] MACRO
1925 The info macro command has new options `-all' and `--'. The first for
1926 printing all definitions of a macro. The second for explicitly specifying
1927 the end of arguments and the beginning of the macro name in case the macro
1928 name starts with a hyphen.
1930 collect[/s] EXPRESSIONS
1931 The tracepoint collect command now takes an optional modifier "/s"
1932 that directs it to dereference pointer-to-character types and
1933 collect the bytes of memory up to a zero byte. The behavior is
1934 similar to what you see when you use the regular print command on a
1935 string. An optional integer following the "/s" sets a bound on the
1936 number of bytes that will be collected.
1939 The trace start command now interprets any supplied arguments as a
1940 note to be recorded with the trace run, with an effect similar to
1941 setting the variable trace-notes.
1944 The trace stop command now interprets any arguments as a note to be
1945 mentioned along with the tstatus report that the trace was stopped
1946 with a command. The effect is similar to setting the variable
1949 * Tracepoints can now be enabled and disabled at any time after a trace
1950 experiment has been started using the standard "enable" and "disable"
1951 commands. It is now possible to start a trace experiment with no enabled
1952 tracepoints; GDB will display a warning, but will allow the experiment to
1953 begin, assuming that tracepoints will be enabled as needed while the trace
1956 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1957 locations with 4-byte instructions, when they were previously
1958 limited to locations with instructions of 5 bytes or longer.
1962 set debug dwarf2-read
1963 show debug dwarf2-read
1964 Turns on or off display of debugging messages related to reading
1965 DWARF debug info. The default is off.
1967 set debug symtab-create
1968 show debug symtab-create
1969 Turns on or off display of debugging messages related to symbol table
1970 creation. The default is off.
1973 show extended-prompt
1974 Set the GDB prompt, and allow escape sequences to be inserted to
1975 display miscellaneous information (see 'help set extended-prompt'
1976 for the list of sequences). This prompt (and any information
1977 accessed through the escape sequences) is updated every time the
1978 prompt is displayed.
1980 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1981 show print entry-values
1982 Set printing of frame argument values at function entry. In some cases
1983 GDB can determine the value of function argument which was passed by the
1984 function caller, even if the value was modified inside the called function.
1986 set debug entry-values
1987 show debug entry-values
1988 Control display of debugging info for determining frame argument values at
1989 function entry and virtual tail call frames.
1991 set basenames-may-differ
1992 show basenames-may-differ
1993 Set whether a source file may have multiple base names.
1994 (A "base name" is the name of a file with the directory part removed.
1995 Example: The base name of "/home/user/hello.c" is "hello.c".)
1996 If set, GDB will canonicalize file names (e.g., expand symlinks)
1997 before comparing them. Canonicalization is an expensive operation,
1998 but it allows the same file be known by more than one base name.
1999 If not set (the default), all source files are assumed to have just
2000 one base name, and gdb will do file name comparisons more efficiently.
2006 Set a user name and notes for the current and any future trace runs.
2007 This is useful for long-running and/or disconnected traces, to
2008 inform others (or yourself) as to who is running the trace, supply
2009 contact information, or otherwise explain what is going on.
2011 set trace-stop-notes
2012 show trace-stop-notes
2013 Set a note attached to the trace run, that is displayed when the
2014 trace has been stopped by a tstop command. This is useful for
2015 instance as an explanation, if you are stopping a trace run that was
2016 started by someone else.
2018 * New remote packets
2022 Dynamically enable a tracepoint in a started trace experiment.
2026 Dynamically disable a tracepoint in a started trace experiment.
2030 Set the user and notes of the trace run.
2034 Query the current status of a tracepoint.
2038 Query the minimum length of instruction at which a fast tracepoint may
2041 * Dcache size (number of lines) and line-size are now runtime-configurable
2042 via "set dcache line" and "set dcache line-size" commands.
2046 Texas Instruments TMS320C6x tic6x-*-*
2050 Renesas RL78 rl78-*-elf
2052 *** Changes in GDB 7.3.1
2054 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2056 *** Changes in GDB 7.3
2058 * GDB has a new command: "thread find [REGEXP]".
2059 It finds the thread id whose name, target id, or thread extra info
2060 matches the given regular expression.
2062 * The "catch syscall" command now works on mips*-linux* targets.
2064 * The -data-disassemble MI command now supports modes 2 and 3 for
2065 dumping the instruction opcodes.
2067 * New command line options
2069 -data-directory DIR Specify DIR as the "data-directory".
2070 This is mostly for testing purposes.
2072 * The "maint set python auto-load on|off" command has been renamed to
2073 "set auto-load-scripts on|off".
2075 * GDB has a new command: "set directories".
2076 It is like the "dir" command except that it replaces the
2077 source path list instead of augmenting it.
2079 * GDB now understands thread names.
2081 On GNU/Linux, "info threads" will display the thread name as set by
2082 prctl or pthread_setname_np.
2084 There is also a new command, "thread name", which can be used to
2085 assign a name internally for GDB to display.
2088 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2089 has been integrated into GDB.
2093 ** The function gdb.Write now accepts an optional keyword 'stream'.
2094 This keyword, when provided, will direct the output to either
2095 stdout, stderr, or GDB's logging output.
2097 ** Parameters can now be be sub-classed in Python, and in particular
2098 you may implement the get_set_doc and get_show_doc functions.
2099 This improves how Parameter set/show documentation is processed
2100 and allows for more dynamic content.
2102 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2103 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2104 have an is_valid method.
2106 ** Breakpoints can now be sub-classed in Python, and in particular
2107 you may implement a 'stop' function that is executed each time
2108 the inferior reaches that breakpoint.
2110 ** New function gdb.lookup_global_symbol looks up a global symbol.
2112 ** GDB values in Python are now callable if the value represents a
2113 function. For example, if 'some_value' represents a function that
2114 takes two integer parameters and returns a value, you can call
2115 that function like so:
2117 result = some_value (10,20)
2119 ** Module gdb.types has been added.
2120 It contains a collection of utilities for working with gdb.Types objects:
2121 get_basic_type, has_field, make_enum_dict.
2123 ** Module gdb.printing has been added.
2124 It contains utilities for writing and registering pretty-printers.
2125 New classes: PrettyPrinter, SubPrettyPrinter,
2126 RegexpCollectionPrettyPrinter.
2127 New function: register_pretty_printer.
2129 ** New commands "info pretty-printers", "enable pretty-printer" and
2130 "disable pretty-printer" have been added.
2132 ** gdb.parameter("directories") is now available.
2134 ** New function gdb.newest_frame returns the newest frame in the
2137 ** The gdb.InferiorThread class has a new "name" attribute. This
2138 holds the thread's name.
2140 ** Python Support for Inferior events.
2141 Python scripts can add observers to be notified of events
2142 occurring in the process being debugged.
2143 The following events are currently supported:
2144 - gdb.events.cont Continue event.
2145 - gdb.events.exited Inferior exited event.
2146 - gdb.events.stop Signal received, and Breakpoint hit events.
2150 ** GDB now puts template parameters in scope when debugging in an
2151 instantiation. For example, if you have:
2153 template<int X> int func (void) { return X; }
2155 then if you step into func<5>, "print X" will show "5". This
2156 feature requires proper debuginfo support from the compiler; it
2157 was added to GCC 4.5.
2159 ** The motion commands "next", "finish", "until", and "advance" now
2160 work better when exceptions are thrown. In particular, GDB will
2161 no longer lose control of the inferior; instead, the GDB will
2162 stop the inferior at the point at which the exception is caught.
2163 This functionality requires a change in the exception handling
2164 code that was introduced in GCC 4.5.
2166 * GDB now follows GCC's rules on accessing volatile objects when
2167 reading or writing target state during expression evaluation.
2168 One notable difference to prior behavior is that "print x = 0"
2169 no longer generates a read of x; the value of the assignment is
2170 now always taken directly from the value being assigned.
2172 * GDB now has some support for using labels in the program's source in
2173 linespecs. For instance, you can use "advance label" to continue
2174 execution to a label.
2176 * GDB now has support for reading and writing a new .gdb_index
2177 section. This section holds a fast index of DWARF debugging
2178 information and can be used to greatly speed up GDB startup and
2179 operation. See the documentation for `save gdb-index' for details.
2181 * The "watch" command now accepts an optional "-location" argument.
2182 When used, this causes GDB to watch the memory referred to by the
2183 expression. Such a watchpoint is never deleted due to it going out
2186 * GDB now supports thread debugging of core dumps on GNU/Linux.
2188 GDB now activates thread debugging using the libthread_db library
2189 when debugging GNU/Linux core dumps, similarly to when debugging
2190 live processes. As a result, when debugging a core dump file, GDB
2191 is now able to display pthread_t ids of threads. For example, "info
2192 threads" shows the same output as when debugging the process when it
2193 was live. In earlier releases, you'd see something like this:
2196 * 1 LWP 6780 main () at main.c:10
2198 While now you see this:
2201 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2203 It is also now possible to inspect TLS variables when debugging core
2206 When debugging a core dump generated on a machine other than the one
2207 used to run GDB, you may need to point GDB at the correct
2208 libthread_db library with the "set libthread-db-search-path"
2209 command. See the user manual for more details on this command.
2211 * When natively debugging programs on PowerPC BookE processors running
2212 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2213 which stop execution of the inferior whenever it executes an instruction
2214 at any address within the specified range. See the "PowerPC Embedded"
2215 section in the user manual for more details.
2217 * New features in the GDB remote stub, GDBserver
2219 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2220 and i686 LynxOS (version 5.x).
2222 ** GDBserver is now supported on Blackfin Linux.
2224 * New native configurations
2226 ia64 HP-UX ia64-*-hpux*
2230 Analog Devices, Inc. Blackfin Processor bfin-*
2232 * Ada task switching is now supported on sparc-elf targets when
2233 debugging a program using the Ravenscar Profile. For more information,
2234 see the "Tasking Support when using the Ravenscar Profile" section
2235 in the GDB user manual.
2237 * Guile support was removed.
2239 * New features in the GNU simulator
2241 ** The --map-info flag lists all known core mappings.
2243 ** CFI flashes may be simulated via the "cfi" device.
2245 *** Changes in GDB 7.2
2247 * Shared library support for remote targets by default
2249 When GDB is configured for a generic, non-OS specific target, like
2250 for example, --target=arm-eabi or one of the many *-*-elf targets,
2251 GDB now queries remote stubs for loaded shared libraries using the
2252 `qXfer:libraries:read' packet. Previously, shared library support
2253 was always disabled for such configurations.
2257 ** Argument Dependent Lookup (ADL)
2259 In C++ ADL lookup directs function search to the namespaces of its
2260 arguments even if the namespace has not been imported.
2270 Here the compiler will search for `foo' in the namespace of 'b'
2271 and find A::foo. GDB now supports this. This construct is commonly
2272 used in the Standard Template Library for operators.
2274 ** Improved User Defined Operator Support
2276 In addition to member operators, GDB now supports lookup of operators
2277 defined in a namespace and imported with a `using' directive, operators
2278 defined in the global scope, operators imported implicitly from an
2279 anonymous namespace, and the ADL operators mentioned in the previous
2281 GDB now also supports proper overload resolution for all the previously
2282 mentioned flavors of operators.
2284 ** static const class members
2286 Printing of static const class members that are initialized in the
2287 class definition has been fixed.
2289 * Windows Thread Information Block access.
2291 On Windows targets, GDB now supports displaying the Windows Thread
2292 Information Block (TIB) structure. This structure is visible either
2293 by using the new command `info w32 thread-information-block' or, by
2294 dereferencing the new convenience variable named `$_tlb', a
2295 thread-specific pointer to the TIB. This feature is also supported
2296 when remote debugging using GDBserver.
2298 * Static tracepoints
2300 Static tracepoints are calls in the user program into a tracing
2301 library. One such library is a port of the LTTng kernel tracer to
2302 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2303 When debugging with GDBserver, GDB now supports combining the GDB
2304 tracepoint machinery with such libraries. For example: the user can
2305 use GDB to probe a static tracepoint marker (a call from the user
2306 program into the tracing library) with the new "strace" command (see
2307 "New commands" below). This creates a "static tracepoint" in the
2308 breakpoint list, that can be manipulated with the same feature set
2309 as fast and regular tracepoints. E.g., collect registers, local and
2310 global variables, collect trace state variables, and define
2311 tracepoint conditions. In addition, the user can collect extra
2312 static tracepoint marker specific data, by collecting the new
2313 $_sdata internal variable. When analyzing the trace buffer, you can
2314 inspect $_sdata like any other variable available to GDB. For more
2315 information, see the "Tracepoints" chapter in GDB user manual. New
2316 remote packets have been defined to support static tracepoints, see
2317 the "New remote packets" section below.
2319 * Better reconstruction of tracepoints after disconnected tracing
2321 GDB will attempt to download the original source form of tracepoint
2322 definitions when starting a trace run, and then will upload these
2323 upon reconnection to the target, resulting in a more accurate
2324 reconstruction of the tracepoints that are in use on the target.
2328 You can now exercise direct control over the ways that GDB can
2329 affect your program. For instance, you can disallow the setting of
2330 breakpoints, so that the program can run continuously (assuming
2331 non-stop mode). In addition, the "observer" variable is available
2332 to switch all of the different controls; in observer mode, GDB
2333 cannot affect the target's behavior at all, which is useful for
2334 tasks like diagnosing live systems in the field.
2336 * The new convenience variable $_thread holds the number of the
2339 * New remote packets
2343 Return the address of the Windows Thread Information Block of a given thread.
2347 In response to several of the tracepoint packets, the target may now
2348 also respond with a number of intermediate `qRelocInsn' request
2349 packets before the final result packet, to have GDB handle
2350 relocating an instruction to execute at a different address. This
2351 is particularly useful for stubs that support fast tracepoints. GDB
2352 reports support for this feature in the qSupported packet.
2356 List static tracepoint markers in the target program.
2360 List static tracepoint markers at a given address in the target
2363 qXfer:statictrace:read
2365 Read the static trace data collected (by a `collect $_sdata'
2366 tracepoint action). The remote stub reports support for this packet
2367 to gdb's qSupported query.
2371 Send the current settings of GDB's permission flags.
2375 Send part of the source (textual) form of a tracepoint definition,
2376 which includes location, conditional, and action list.
2378 * The source command now accepts a -s option to force searching for the
2379 script in the source search path even if the script name specifies
2382 * New features in the GDB remote stub, GDBserver
2384 - GDBserver now support tracepoints (including fast tracepoints, and
2385 static tracepoints). The feature is currently supported by the
2386 i386-linux and amd64-linux builds. See the "Tracepoints support
2387 in gdbserver" section in the manual for more information.
2389 GDBserver JIT compiles the tracepoint's conditional agent
2390 expression bytecode into native code whenever possible for low
2391 overhead dynamic tracepoints conditionals. For such tracepoints,
2392 an expression that examines program state is evaluated when the
2393 tracepoint is reached, in order to determine whether to capture
2394 trace data. If the condition is simple and false, processing the
2395 tracepoint finishes very quickly and no data is gathered.
2397 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2398 for static tracepoints support.
2400 - GDBserver now supports x86_64 Windows 64-bit debugging.
2402 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2403 it understands register description.
2405 * The --batch flag now disables pagination and queries.
2407 * X86 general purpose registers
2409 GDB now supports reading/writing byte, word and double-word x86
2410 general purpose registers directly. This means you can use, say,
2411 $ah or $ax to refer, respectively, to the byte register AH and
2412 16-bit word register AX that are actually portions of the 32-bit
2413 register EAX or 64-bit register RAX.
2415 * The `commands' command now accepts a range of breakpoints to modify.
2416 A plain `commands' following a command that creates multiple
2417 breakpoints affects all the breakpoints set by that command. This
2418 applies to breakpoints set by `rbreak', and also applies when a
2419 single `break' command creates multiple breakpoints (e.g.,
2420 breakpoints on overloaded c++ functions).
2422 * The `rbreak' command now accepts a filename specification as part of
2423 its argument, limiting the functions selected by the regex to those
2424 in the specified file.
2426 * Support for remote debugging Windows and SymbianOS shared libraries
2427 from Unix hosts has been improved. Non Windows GDB builds now can
2428 understand target reported file names that follow MS-DOS based file
2429 system semantics, such as file names that include drive letters and
2430 use the backslash character as directory separator. This makes it
2431 possible to transparently use the "set sysroot" and "set
2432 solib-search-path" on Unix hosts to point as host copies of the
2433 target's shared libraries. See the new command "set
2434 target-file-system-kind" described below, and the "Commands to
2435 specify files" section in the user manual for more information.
2439 eval template, expressions...
2440 Convert the values of one or more expressions under the control
2441 of the string template to a command line, and call it.
2443 set target-file-system-kind unix|dos-based|auto
2444 show target-file-system-kind
2445 Set or show the assumed file system kind for target reported file
2448 save breakpoints <filename>
2449 Save all current breakpoint definitions to a file suitable for use
2450 in a later debugging session. To read the saved breakpoint
2451 definitions, use the `source' command.
2453 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2456 info static-tracepoint-markers
2457 Display information about static tracepoint markers in the target.
2459 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2460 Define a static tracepoint by probing a marker at the given
2461 function, line, address, or marker ID.
2465 Enable and disable observer mode.
2467 set may-write-registers on|off
2468 set may-write-memory on|off
2469 set may-insert-breakpoints on|off
2470 set may-insert-tracepoints on|off
2471 set may-insert-fast-tracepoints on|off
2472 set may-interrupt on|off
2473 Set individual permissions for GDB effects on the target. Note that
2474 some of these settings can have undesirable or surprising
2475 consequences, particularly when changed in the middle of a session.
2476 For instance, disabling the writing of memory can prevent
2477 breakpoints from being inserted, cause single-stepping to fail, or
2478 even crash your program, if you disable after breakpoints have been
2479 inserted. However, GDB should not crash.
2481 set record memory-query on|off
2482 show record memory-query
2483 Control whether to stop the inferior if memory changes caused
2484 by an instruction cannot be recorded.
2489 The disassemble command now supports "start,+length" form of two arguments.
2493 ** GDB now provides a new directory location, called the python directory,
2494 where Python scripts written for GDB can be installed. The location
2495 of that directory is <data-directory>/python, where <data-directory>
2496 is the GDB data directory. For more details, see section `Scripting
2497 GDB using Python' in the manual.
2499 ** The GDB Python API now has access to breakpoints, symbols, symbol
2500 tables, program spaces, inferiors, threads and frame's code blocks.
2501 Additionally, GDB Parameters can now be created from the API, and
2502 manipulated via set/show in the CLI.
2504 ** New functions gdb.target_charset, gdb.target_wide_charset,
2505 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2507 ** New exception gdb.GdbError.
2509 ** Pretty-printers are now also looked up in the current program space.
2511 ** Pretty-printers can now be individually enabled and disabled.
2513 ** GDB now looks for names of Python scripts to auto-load in a
2514 special section named `.debug_gdb_scripts', in addition to looking
2515 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2517 * Tracepoint actions were unified with breakpoint commands. In particular,
2518 there are no longer differences in "info break" output for breakpoints and
2519 tracepoints and the "commands" command can be used for both tracepoints and
2520 regular breakpoints.
2524 ARM Symbian arm*-*-symbianelf*
2526 * D language support.
2527 GDB now supports debugging programs written in the D programming
2530 * GDB now supports the extended ptrace interface for PowerPC which is
2531 available since Linux kernel version 2.6.34. This automatically enables
2532 any hardware breakpoints and additional hardware watchpoints available in
2533 the processor. The old ptrace interface exposes just one hardware
2534 watchpoint and no hardware breakpoints.
2536 * GDB is now able to use the Data Value Compare (DVC) register available on
2537 embedded PowerPC processors to implement in hardware simple watchpoint
2538 conditions of the form:
2540 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2542 This works in native GDB running on Linux kernels with the extended ptrace
2543 interface mentioned above.
2545 *** Changes in GDB 7.1
2549 ** Namespace Support
2551 GDB now supports importing of namespaces in C++. This enables the
2552 user to inspect variables from imported namespaces. Support for
2553 namepace aliasing has also been added. So, if a namespace is
2554 aliased in the current scope (e.g. namepace C=A; ) the user can
2555 print variables using the alias (e.g. (gdb) print C::x).
2559 All known bugs relating to the printing of virtual base class were
2560 fixed. It is now possible to call overloaded static methods using a
2565 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2566 and reinterpret_cast<> are now handled by the C++ expression parser.
2570 Xilinx MicroBlaze microblaze-*-*
2575 Xilinx MicroBlaze microblaze
2578 * Multi-program debugging.
2580 GDB now has support for multi-program (a.k.a. multi-executable or
2581 multi-exec) debugging. This allows for debugging multiple inferiors
2582 simultaneously each running a different program under the same GDB
2583 session. See "Debugging Multiple Inferiors and Programs" in the
2584 manual for more information. This implied some user visible changes
2585 in the multi-inferior support. For example, "info inferiors" now
2586 lists inferiors that are not running yet or that have exited
2587 already. See also "New commands" and "New options" below.
2589 * New tracing features
2591 GDB's tracepoint facility now includes several new features:
2593 ** Trace state variables
2595 GDB tracepoints now include support for trace state variables, which
2596 are variables managed by the target agent during a tracing
2597 experiment. They are useful for tracepoints that trigger each
2598 other, so for instance one tracepoint can count hits in a variable,
2599 and then a second tracepoint has a condition that is true when the
2600 count reaches a particular value. Trace state variables share the
2601 $-syntax of GDB convenience variables, and can appear in both
2602 tracepoint actions and condition expressions. Use the "tvariable"
2603 command to create, and "info tvariables" to view; see "Trace State
2604 Variables" in the manual for more detail.
2608 GDB now includes an option for defining fast tracepoints, which
2609 targets may implement more efficiently, such as by installing a jump
2610 into the target agent rather than a trap instruction. The resulting
2611 speedup can be by two orders of magnitude or more, although the
2612 tradeoff is that some program locations on some target architectures
2613 might not allow fast tracepoint installation, for instance if the
2614 instruction to be replaced is shorter than the jump. To request a
2615 fast tracepoint, use the "ftrace" command, with syntax identical to
2616 the regular trace command.
2618 ** Disconnected tracing
2620 It is now possible to detach GDB from the target while it is running
2621 a trace experiment, then reconnect later to see how the experiment
2622 is going. In addition, a new variable disconnected-tracing lets you
2623 tell the target agent whether to continue running a trace if the
2624 connection is lost unexpectedly.
2628 GDB now has the ability to save the trace buffer into a file, and
2629 then use that file as a target, similarly to you can do with
2630 corefiles. You can select trace frames, print data that was
2631 collected in them, and use tstatus to display the state of the
2632 tracing run at the moment that it was saved. To create a trace
2633 file, use "tsave <filename>", and to use it, do "target tfile
2636 ** Circular trace buffer
2638 You can ask the target agent to handle the trace buffer as a
2639 circular buffer, discarding the oldest trace frames to make room for
2640 newer ones, by setting circular-trace-buffer to on. This feature may
2641 not be available for all target agents.
2646 The disassemble command, when invoked with two arguments, now requires
2647 the arguments to be comma-separated.
2650 The info variables command now displays variable definitions. Files
2651 which only declare a variable are not shown.
2654 The source command is now capable of sourcing Python scripts.
2655 This feature is dependent on the debugger being build with Python
2658 Related to this enhancement is also the introduction of a new command
2659 "set script-extension" (see below).
2661 * New commands (for set/show, see "New options" below)
2663 record save [<FILENAME>]
2664 Save a file (in core file format) containing the process record
2665 execution log for replay debugging at a later time.
2667 record restore <FILENAME>
2668 Restore the process record execution log that was saved at an
2669 earlier time, for replay debugging.
2671 add-inferior [-copies <N>] [-exec <FILENAME>]
2674 clone-inferior [-copies <N>] [ID]
2675 Make a new inferior ready to execute the same program another
2676 inferior has loaded.
2681 maint info program-spaces
2682 List the program spaces loaded into GDB.
2684 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2685 show remote interrupt-sequence
2686 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2687 as the sequence to the remote target in order to interrupt the execution.
2688 Ctrl-C is a default. Some system prefers BREAK which is high level of
2689 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2690 Magic SysRq g. It is BREAK signal and character 'g'.
2692 set remote interrupt-on-connect [on | off]
2693 show remote interrupt-on-connect
2694 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2695 remote target when gdb connects to it. This is needed when you debug
2698 set remotebreak [on | off]
2700 Deprecated. Use "set/show remote interrupt-sequence" instead.
2702 tvariable $NAME [ = EXP ]
2703 Create or modify a trace state variable.
2706 List trace state variables and their values.
2708 delete tvariable $NAME ...
2709 Delete one or more trace state variables.
2712 Evaluate the given expressions without collecting anything into the
2713 trace buffer. (Valid in tracepoint actions only.)
2715 ftrace FN / FILE:LINE / *ADDR
2716 Define a fast tracepoint at the given function, line, or address.
2718 * New expression syntax
2720 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2721 GDB now parses 0b101010 identically with 42.
2725 set follow-exec-mode new|same
2726 show follow-exec-mode
2727 Control whether GDB reuses the same inferior across an exec call or
2728 creates a new one. This is useful to be able to restart the old
2729 executable after the inferior having done an exec call.
2731 set default-collect EXPR, ...
2732 show default-collect
2733 Define a list of expressions to be collected at each tracepoint.
2734 This is a useful way to ensure essential items are not overlooked,
2735 such as registers or a critical global variable.
2737 set disconnected-tracing
2738 show disconnected-tracing
2739 If set to 1, the target is instructed to continue tracing if it
2740 loses its connection to GDB. If 0, the target is to stop tracing
2743 set circular-trace-buffer
2744 show circular-trace-buffer
2745 If set to on, the target is instructed to use a circular trace buffer
2746 and discard the oldest trace frames instead of stopping the trace due
2747 to a full trace buffer. If set to off, the trace stops when the buffer
2748 fills up. Some targets may not support this.
2750 set script-extension off|soft|strict
2751 show script-extension
2752 If set to "off", the debugger does not perform any script language
2753 recognition, and all sourced files are assumed to be GDB scripts.
2754 If set to "soft" (the default), files are sourced according to
2755 filename extension, falling back to GDB scripts if the first
2757 If set to "strict", files are sourced according to filename extension.
2759 set ada trust-PAD-over-XVS on|off
2760 show ada trust-PAD-over-XVS
2761 If off, activate a workaround against a bug in the debugging information
2762 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2763 the GCC sources for more information about the GNAT encoding and
2764 PAD types in particular). It is always safe to set this option to
2765 off, but this introduces a slight performance penalty. The default
2768 * Python API Improvements
2770 ** GDB provides the new class gdb.LazyString. This is useful in
2771 some pretty-printing cases. The new method gdb.Value.lazy_string
2772 provides a simple way to create objects of this type.
2774 ** The fields returned by gdb.Type.fields now have an
2775 `is_base_class' attribute.
2777 ** The new method gdb.Type.range returns the range of an array type.
2779 ** The new method gdb.parse_and_eval can be used to parse and
2780 evaluate an expression.
2782 * New remote packets
2785 Define a trace state variable.
2788 Get the current value of a trace state variable.
2791 Set desired tracing behavior upon disconnection.
2794 Set the trace buffer to be linear or circular.
2797 Get data about the tracepoints currently in use.
2801 Process record now works correctly with hardware watchpoints.
2803 Multiple bug fixes have been made to the mips-irix port, making it
2804 much more reliable. In particular:
2805 - Debugging threaded applications is now possible again. Previously,
2806 GDB would hang while starting the program, or while waiting for
2807 the program to stop at a breakpoint.
2808 - Attaching to a running process no longer hangs.
2809 - An error occurring while loading a core file has been fixed.
2810 - Changing the value of the PC register now works again. This fixes
2811 problems observed when using the "jump" command, or when calling
2812 a function from GDB, or even when assigning a new value to $pc.
2813 - With the "finish" and "return" commands, the return value for functions
2814 returning a small array is now correctly printed.
2815 - It is now possible to break on shared library code which gets executed
2816 during a shared library init phase (code executed while executing
2817 their .init section). Previously, the breakpoint would have no effect.
2818 - GDB is now able to backtrace through the signal handler for
2819 non-threaded programs.
2821 PIE (Position Independent Executable) programs debugging is now supported.
2822 This includes debugging execution of PIC (Position Independent Code) shared
2823 libraries although for that, it should be possible to run such libraries as an
2826 *** Changes in GDB 7.0
2828 * GDB now has an interface for JIT compilation. Applications that
2829 dynamically generate code can create symbol files in memory and register
2830 them with GDB. For users, the feature should work transparently, and
2831 for JIT developers, the interface is documented in the GDB manual in the
2832 "JIT Compilation Interface" chapter.
2834 * Tracepoints may now be conditional. The syntax is as for
2835 breakpoints; either an "if" clause appended to the "trace" command,
2836 or the "condition" command is available. GDB sends the condition to
2837 the target for evaluation using the same bytecode format as is used
2838 for tracepoint actions.
2840 * The disassemble command now supports: an optional /r modifier, print the
2841 raw instructions in hex as well as in symbolic form, and an optional /m
2842 modifier to print mixed source+assembly.
2844 * Process record and replay
2846 In a architecture environment that supports ``process record and
2847 replay'', ``process record and replay'' target can record a log of
2848 the process execution, and replay it with both forward and reverse
2851 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2852 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2853 set execution-direction {forward|reverse}, for targets that support
2856 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2857 feature is available with a native GDB running on kernel version
2860 * GDB now has support for multi-byte and wide character sets on the
2861 target. Strings whose character type is wchar_t, char16_t, or
2862 char32_t are now correctly printed. GDB supports wide- and unicode-
2863 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2864 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2865 `printf'. This feature requires iconv to work properly; if your
2866 system does not have a working iconv, GDB can use GNU libiconv. See
2867 the installation instructions for more information.
2869 * GDB now supports automatic retrieval of shared library files from
2870 remote targets. To use this feature, specify a system root that begins
2871 with the `remote:' prefix, either via the `set sysroot' command or via
2872 the `--with-sysroot' configure-time option.
2874 * "info sharedlibrary" now takes an optional regex of libraries to show,
2875 and it now reports if a shared library has no debugging information.
2877 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2878 now complete on file names.
2880 * When completing in expressions, gdb will attempt to limit
2881 completions to allowable structure or union fields, where appropriate.
2882 For instance, consider:
2884 # struct example { int f1; double f2; };
2885 # struct example variable;
2888 If the user types TAB at the end of this command line, the available
2889 completions will be "f1" and "f2".
2891 * Inlined functions are now supported. They show up in backtraces, and
2892 the "step", "next", and "finish" commands handle them automatically.
2894 * GDB now supports the token-splicing (##) and stringification (#)
2895 operators when expanding macros. It also supports variable-arity
2898 * GDB now supports inspecting extra signal information, exported by
2899 the new $_siginfo convenience variable. The feature is currently
2900 implemented on linux ARM, i386 and amd64.
2902 * GDB can now display the VFP floating point registers and NEON vector
2903 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2904 can provide these registers (requires Linux 2.6.30 or later). Remote
2905 and simulator targets may also provide them.
2907 * New remote packets
2910 Search memory for a sequence of bytes.
2913 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2914 operation over reliable transport links. Use of this packet is
2915 controlled by the `set remote noack-packet' command.
2918 Kill the process with the specified process ID. Use this in preference
2919 to `k' when multiprocess protocol extensions are supported.
2922 Obtains additional operating system information
2926 Read or write additional signal information.
2928 * Removed remote protocol undocumented extension
2930 An undocumented extension to the remote protocol's `S' stop reply
2931 packet that permited the stub to pass a process id was removed.
2932 Remote servers should use the `T' stop reply packet instead.
2934 * GDB now supports multiple function calling conventions according to the
2935 DWARF-2 DW_AT_calling_convention function attribute.
2937 * The SH target utilizes the aforementioned change to distinguish between gcc
2938 and Renesas calling convention. It also adds the new CLI commands
2939 `set/show sh calling-convention'.
2941 * GDB can now read compressed debug sections, as produced by GNU gold
2942 with the --compress-debug-sections=zlib flag.
2944 * 64-bit core files are now supported on AIX.
2946 * Thread switching is now supported on Tru64.
2948 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2949 which will be allocated using malloc later in program execution.
2951 * The qXfer:libraries:read remote procotol packet now allows passing a
2952 list of section offsets.
2954 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2955 conditions handling signals delivered during attach or thread creation
2956 have also been fixed.
2958 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2959 From the user's standpoint, all unqualified instances of True and False
2960 are treated as the standard definitions, regardless of context.
2962 * GDB now parses C++ symbol and type names more flexibly. For
2965 template<typename T> class C { };
2968 GDB will now correctly handle all of:
2970 ptype C<char const *>
2971 ptype C<char const*>
2972 ptype C<const char *>
2973 ptype C<const char*>
2975 * New features in the GDB remote stub, gdbserver
2977 - The "--wrapper" command-line argument tells gdbserver to use a
2978 wrapper program to launch programs for debugging.
2980 - On PowerPC and S/390 targets, it is now possible to use a single
2981 gdbserver executable to debug both 32-bit and 64-bit programs.
2982 (This requires gdbserver itself to be built as a 64-bit executable.)
2984 - gdbserver uses the new noack protocol mode for TCP connections to
2985 reduce communications latency, if also supported and enabled in GDB.
2987 - Support for the sparc64-linux-gnu target is now included in
2990 - The amd64-linux build of gdbserver now supports debugging both
2991 32-bit and 64-bit programs.
2993 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2994 now support hardware watchpoints, and will use them automatically
2999 GDB now has support for scripting using Python. Whether this is
3000 available is determined at configure time.
3002 New GDB commands can now be written in Python.
3004 * Ada tasking support
3006 Ada tasks can now be inspected in GDB. The following commands have
3010 Print the list of Ada tasks.
3012 Print detailed information about task number N.
3014 Print the task number of the current task.
3016 Switch the context of debugging to task number N.
3018 * Support for user-defined prefixed commands. The "define" command can
3019 add new commands to existing prefixes, e.g. "target".
3021 * Multi-inferior, multi-process debugging.
3023 GDB now has generalized support for multi-inferior debugging. See
3024 "Debugging Multiple Inferiors" in the manual for more information.
3025 Although availability still depends on target support, the command
3026 set is more uniform now. The GNU/Linux specific multi-forks support
3027 has been migrated to this new framework. This implied some user
3028 visible changes; see "New commands" and also "Removed commands"
3031 * Target descriptions can now describe the target OS ABI. See the
3032 "Target Description Format" section in the user manual for more
3035 * Target descriptions can now describe "compatible" architectures
3036 to indicate that the target can execute applications for a different
3037 architecture in addition to those for the main target architecture.
3038 See the "Target Description Format" section in the user manual for
3041 * Multi-architecture debugging.
3043 GDB now includes general supports for debugging applications on
3044 hybrid systems that use more than one single processor architecture
3045 at the same time. Each such hybrid architecture still requires
3046 specific support to be added. The only hybrid architecture supported
3047 in this version of GDB is the Cell Broadband Engine.
3049 * GDB now supports integrated debugging of Cell/B.E. applications that
3050 use both the PPU and SPU architectures. To enable support for hybrid
3051 Cell/B.E. debugging, you need to configure GDB to support both the
3052 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3053 --enable-targets configure option.
3055 * Non-stop mode debugging.
3057 For some targets, GDB now supports an optional mode of operation in
3058 which you can examine stopped threads while other threads continue
3059 to execute freely. This is referred to as non-stop mode, with the
3060 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3061 section in the user manual for more information.
3063 To be able to support remote non-stop debugging, a remote stub needs
3064 to implement the non-stop mode remote protocol extensions, as
3065 described in the "Remote Non-Stop" section of the user manual. The
3066 GDB remote stub, gdbserver, has been adjusted to support these
3067 extensions on linux targets.
3069 * New commands (for set/show, see "New options" below)
3071 catch syscall [NAME(S) | NUMBER(S)]
3072 Catch system calls. Arguments, which should be names of system
3073 calls or their numbers, mean catch only those syscalls. Without
3074 arguments, every syscall will be caught. When the inferior issues
3075 any of the specified syscalls, GDB will stop and announce the system
3076 call, both when it is called and when its call returns. This
3077 feature is currently available with a native GDB running on the
3078 Linux Kernel, under the following architectures: x86, x86_64,
3079 PowerPC and PowerPC64.
3081 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3083 Search memory for a sequence of bytes.
3085 maint set python print-stack
3086 maint show python print-stack
3087 Show a stack trace when an error is encountered in a Python script.
3090 Invoke CODE by passing it to the Python interpreter.
3095 These allow macros to be defined, undefined, and listed
3099 Show operating system information about processes.
3102 List the inferiors currently under GDB's control.
3105 Switch focus to inferior number NUM.
3108 Detach from inferior number NUM.
3111 Kill inferior number NUM.
3115 set spu stop-on-load
3116 show spu stop-on-load
3117 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3119 set spu auto-flush-cache
3120 show spu auto-flush-cache
3121 Control whether to automatically flush the software-managed cache
3122 during Cell/B.E. debugging.
3124 set sh calling-convention
3125 show sh calling-convention
3126 Control the calling convention used when calling SH target functions.
3129 show debug timestamp
3130 Control display of timestamps with GDB debugging output.
3132 set disassemble-next-line
3133 show disassemble-next-line
3134 Control display of disassembled source lines or instructions when
3137 set remote noack-packet
3138 show remote noack-packet
3139 Set/show the use of remote protocol QStartNoAckMode packet. See above
3140 under "New remote packets."
3142 set remote query-attached-packet
3143 show remote query-attached-packet
3144 Control use of remote protocol `qAttached' (query-attached) packet.
3146 set remote read-siginfo-object
3147 show remote read-siginfo-object
3148 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3151 set remote write-siginfo-object
3152 show remote write-siginfo-object
3153 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3156 set remote reverse-continue
3157 show remote reverse-continue
3158 Control use of remote protocol 'bc' (reverse-continue) packet.
3160 set remote reverse-step
3161 show remote reverse-step
3162 Control use of remote protocol 'bs' (reverse-step) packet.
3164 set displaced-stepping
3165 show displaced-stepping
3166 Control displaced stepping mode. Displaced stepping is a way to
3167 single-step over breakpoints without removing them from the debuggee.
3168 Also known as "out-of-line single-stepping".
3171 show debug displaced
3172 Control display of debugging info for displaced stepping.
3174 maint set internal-error
3175 maint show internal-error
3176 Control what GDB does when an internal error is detected.
3178 maint set internal-warning
3179 maint show internal-warning
3180 Control what GDB does when an internal warning is detected.
3185 Use a wrapper program to launch programs for debugging.
3187 set multiple-symbols (all|ask|cancel)
3188 show multiple-symbols
3189 The value of this variable can be changed to adjust the debugger behavior
3190 when an expression or a breakpoint location contains an ambiguous symbol
3191 name (an overloaded function name, for instance).
3193 set breakpoint always-inserted
3194 show breakpoint always-inserted
3195 Keep breakpoints always inserted in the target, as opposed to inserting
3196 them when resuming the target, and removing them when the target stops.
3197 This option can improve debugger performance on slow remote targets.
3199 set arm fallback-mode (arm|thumb|auto)
3200 show arm fallback-mode
3201 set arm force-mode (arm|thumb|auto)
3203 These commands control how ARM GDB determines whether instructions
3204 are ARM or Thumb. The default for both settings is auto, which uses
3205 the current CPSR value for instructions without symbols; previous
3206 versions of GDB behaved as if "set arm fallback-mode arm".
3208 set disable-randomization
3209 show disable-randomization
3210 Standalone programs run with the virtual address space randomization enabled
3211 by default on some platforms. This option keeps the addresses stable across
3212 multiple debugging sessions.
3216 Control whether other threads are stopped or not when some thread hits
3221 Requests that asynchronous execution is enabled in the target, if available.
3222 In this case, it's possible to resume target in the background, and interact
3223 with GDB while the target is running. "show target-async" displays the
3224 current state of asynchronous execution of the target.
3226 set target-wide-charset
3227 show target-wide-charset
3228 The target-wide-charset is the name of the character set that GDB
3229 uses when printing characters whose type is wchar_t.
3231 set tcp auto-retry (on|off)
3233 set tcp connect-timeout
3234 show tcp connect-timeout
3235 These commands allow GDB to retry failed TCP connections to a remote stub
3236 with a specified timeout period; this is useful if the stub is launched
3237 in parallel with GDB but may not be ready to accept connections immediately.
3239 set libthread-db-search-path
3240 show libthread-db-search-path
3241 Control list of directories which GDB will search for appropriate
3244 set schedule-multiple (on|off)
3245 show schedule-multiple
3246 Allow GDB to resume all threads of all processes or only threads of
3247 the current process.
3251 Use more aggressive caching for accesses to the stack. This improves
3252 performance of remote debugging (particularly backtraces) without
3253 affecting correctness.
3255 set interactive-mode (on|off|auto)
3256 show interactive-mode
3257 Control whether GDB runs in interactive mode (on) or not (off).
3258 When in interactive mode, GDB waits for the user to answer all
3259 queries. Otherwise, GDB does not wait and assumes the default
3260 answer. When set to auto (the default), GDB determines which
3261 mode to use based on the stdin settings.
3266 For program forks, this is replaced by the new more generic `info
3267 inferiors' command. To list checkpoints, you can still use the
3268 `info checkpoints' command, which was an alias for the `info forks'
3272 Replaced by the new `inferior' command. To switch between
3273 checkpoints, you can still use the `restart' command, which was an
3274 alias for the `fork' command.
3277 This is removed, since some targets don't have a notion of
3278 processes. To switch between processes, you can still use the
3279 `inferior' command using GDB's own inferior number.
3282 For program forks, this is replaced by the new more generic `kill
3283 inferior' command. To delete a checkpoint, you can still use the
3284 `delete checkpoint' command, which was an alias for the `delete
3288 For program forks, this is replaced by the new more generic `detach
3289 inferior' command. To detach a checkpoint, you can still use the
3290 `detach checkpoint' command, which was an alias for the `detach
3293 * New native configurations
3295 x86/x86_64 Darwin i[34567]86-*-darwin*
3297 x86_64 MinGW x86_64-*-mingw*
3301 Lattice Mico32 lm32-*
3302 x86 DICOS i[34567]86-*-dicos*
3303 x86_64 DICOS x86_64-*-dicos*
3306 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3307 (mingw32ce) debugging.
3313 These commands were actually not implemented on any target.
3315 *** Changes in GDB 6.8
3317 * New native configurations
3319 NetBSD/hppa hppa*-*netbsd*
3320 Xtensa GNU/Linux xtensa*-*-linux*
3324 NetBSD/hppa hppa*-*-netbsd*
3325 Xtensa GNU/Lunux xtensa*-*-linux*
3327 * Change in command line behavior -- corefiles vs. process ids.
3329 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3330 attaching to process NUMBER fails, GDB no longer attempts to open a
3331 core file named NUMBER. Attaching to a program using the -c option
3332 is no longer supported. Instead, use the '-p' or '--pid' options.
3334 * GDB can now be built as a native debugger for debugging Windows x86
3335 (mingw32) Portable Executable (PE) programs.
3337 * Pending breakpoints no longer change their number when their address
3340 * GDB now supports breakpoints with multiple locations,
3341 including breakpoints on C++ constructors, inside C++ templates,
3342 and in inlined functions.
3344 * GDB's ability to debug optimized code has been improved. GDB more
3345 accurately identifies function bodies and lexical blocks that occupy
3346 more than one contiguous range of addresses.
3348 * Target descriptions can now describe registers for PowerPC.
3350 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3351 registers on PowerPC targets.
3353 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3354 targets even when the libthread_db library is not available.
3356 * The GDB remote stub, gdbserver, now supports the new file transfer
3357 commands (remote put, remote get, and remote delete).
3359 * The GDB remote stub, gdbserver, now supports run and attach in
3360 extended-remote mode.
3362 * hppa*64*-*-hpux11* target broken
3363 The debugger is unable to start a program and fails with the following
3364 error: "Error trying to get information about dynamic linker".
3365 The gdb-6.7 release is also affected.
3367 * GDB now supports the --enable-targets= configure option to allow
3368 building a single GDB executable that supports multiple remote
3369 target architectures.
3371 * GDB now supports debugging C and C++ programs which use the
3372 Decimal Floating Point extension. In addition, the PowerPC target
3373 now has a set of pseudo-registers to inspect decimal float values
3374 stored in two consecutive float registers.
3376 * The -break-insert MI command can optionally create pending
3379 * Improved support for debugging Ada
3380 Many improvements to the Ada language support have been made. These
3382 - Better support for Ada2005 interface types
3383 - Improved handling of arrays and slices in general
3384 - Better support for Taft-amendment types
3385 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3387 - Improved command completion in Ada
3390 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3395 set print frame-arguments (all|scalars|none)
3396 show print frame-arguments
3397 The value of this variable can be changed to control which argument
3398 values should be printed by the debugger when displaying a frame.
3403 Transfer files to and from a remote target, and delete remote files.
3410 Transfer files to and from a remote target, and delete remote files.
3412 * New remote packets
3419 Open, close, read, write, and delete files on the remote system.
3422 Attach to an existing process on the remote system, in extended-remote
3426 Run a new process on the remote system, in extended-remote mode.
3428 *** Changes in GDB 6.7
3430 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3431 bfd, libiberty and opcodes, as revealed by static analysis donated by
3432 Coverity, Inc. (http://scan.coverity.com).
3434 * When looking up multiply-defined global symbols, GDB will now prefer the
3435 symbol definition in the current shared library if it was built using the
3436 -Bsymbolic linker option.
3438 * When the Text User Interface (TUI) is not configured, GDB will now
3439 recognize the -tui command-line option and print a message that the TUI
3442 * The GDB remote stub, gdbserver, now has lower overhead for high
3443 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3445 * GDB for MIPS targets now autodetects whether a remote target provides
3446 32-bit or 64-bit register values.
3448 * Support for C++ member pointers has been improved.
3450 * GDB now understands XML target descriptions, which specify the
3451 target's overall architecture. GDB can read a description from
3452 a local file or over the remote serial protocol.
3454 * Vectors of single-byte data use a new integer type which is not
3455 automatically displayed as character or string data.
3457 * The /s format now works with the print command. It displays
3458 arrays of single-byte integers and pointers to single-byte integers
3461 * Target descriptions can now describe target-specific registers,
3462 for architectures which have implemented the support (currently
3463 only ARM, M68K, and MIPS).
3465 * GDB and the GDB remote stub, gdbserver, now support the XScale
3468 * The GDB remote stub, gdbserver, has been updated to support
3469 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3470 has been rewritten to use the standard GDB remote protocol.
3472 * GDB can now step into C++ functions which are called through thunks.
3474 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3476 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3477 layout. It also supports a TextSeg= and DataSeg= response when only
3478 segment base addresses (rather than offsets) are available.
3480 * The /i format now outputs any trailing branch delay slot instructions
3481 immediately following the last instruction within the count specified.
3483 * The GDB remote protocol "T" stop reply packet now supports a
3484 "library" response. Combined with the new "qXfer:libraries:read"
3485 packet, this response allows GDB to debug shared libraries on targets
3486 where the operating system manages the list of loaded libraries (e.g.
3487 Windows and SymbianOS).
3489 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3490 (DLLs) on Windows and Windows CE targets.
3492 * GDB now supports a faster verification that a .debug file matches its binary
3493 according to its build-id signature, if the signature is present.
3499 Enable or disable hardware flow control (RTS/CTS) on the serial port
3500 when debugging using remote targets.
3502 set mem inaccessible-by-default
3503 show mem inaccessible-by-default
3504 If the target supplies a memory map, for instance via the remote
3505 protocol's "qXfer:memory-map:read" packet, setting this variable
3506 prevents GDB from accessing memory outside the memory map. This
3507 is useful for targets with memory mapped registers or which react
3508 badly to accesses of unmapped address space.
3510 set breakpoint auto-hw
3511 show breakpoint auto-hw
3512 If the target supplies a memory map, for instance via the remote
3513 protocol's "qXfer:memory-map:read" packet, setting this variable
3514 lets GDB use hardware breakpoints automatically for memory regions
3515 where it can not use software breakpoints. This covers both the
3516 "break" command and internal breakpoints used for other commands
3517 including "next" and "finish".
3520 catch exception unhandled
3521 Stop the program execution when Ada exceptions are raised.
3524 Stop the program execution when an Ada assertion failed.
3528 Set an alternate system root for target files. This is a more
3529 general version of "set solib-absolute-prefix", which is now
3530 an alias to "set sysroot".
3533 Provide extended SPU facility status information. This set of
3534 commands is available only when debugging the Cell/B.E. SPU
3537 * New native configurations
3539 OpenBSD/sh sh*-*openbsd*
3542 unset tdesc filename
3544 Use the specified local file as an XML target description, and do
3545 not query the target for its built-in description.
3549 OpenBSD/sh sh*-*-openbsd*
3550 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3551 Toshiba Media Processor mep-elf
3553 * New remote packets
3556 Ignore the specified signals; pass them directly to the debugged program
3557 without stopping other threads or reporting them to GDB.
3559 qXfer:features:read:
3560 Read an XML target description from the target, which describes its
3565 Read or write contents of an spufs file on the target system. These
3566 packets are available only on the Cell/B.E. SPU architecture.
3568 qXfer:libraries:read:
3569 Report the loaded shared libraries. Combined with new "T" packet
3570 response, this packet allows GDB to debug shared libraries on
3571 targets where the operating system manages the list of loaded
3572 libraries (e.g. Windows and SymbianOS).
3576 Support for these obsolete configurations has been removed.
3584 i[34567]86-*-lynxos*
3585 i[34567]86-*-netware*
3586 i[34567]86-*-sco3.2v5*
3587 i[34567]86-*-sco3.2v4*
3589 i[34567]86-*-sysv4.2*
3592 i[34567]86-*-unixware2*
3593 i[34567]86-*-unixware*
3602 * Other removed features
3609 Various m68k-only ROM monitors.
3616 Various Renesas ROM monitors and debugging interfaces for SH and
3621 Support for a Macraigor serial interface to on-chip debugging.
3622 GDB does not directly support the newer parallel or USB
3627 A debug information format. The predecessor to DWARF 2 and
3628 DWARF 3, which are still supported.
3630 Support for the HP aCC compiler on HP-UX/PA-RISC
3632 SOM-encapsulated symbolic debugging information, automatic
3633 invocation of pxdb, and the aCC custom C++ ABI. This does not
3634 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3635 with aCC can still be debugged on an assembly level.
3637 MIPS ".pdr" sections
3639 A MIPS-specific format used to describe stack frame layout
3640 in debugging information.
3644 GDB could work with an older version of Guile to debug
3645 the interpreter and Scheme programs running in it.
3647 set mips stack-arg-size
3648 set mips saved-gpreg-size
3650 Use "set mips abi" to control parameter passing for MIPS.
3652 *** Changes in GDB 6.6
3657 Cell Broadband Engine SPU spu-elf
3659 * GDB can now be configured as a cross-debugger targeting native Windows
3660 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3661 running on a Windows system over TCP/IP to debug Windows programs.
3663 * The GDB remote stub, gdbserver, has been updated to support Windows and
3664 Cygwin debugging. Both single-threaded and multi-threaded programs are
3667 * The "set trust-readonly-sections" command works again. This command was
3668 broken in GDB 6.3, 6.4, and 6.5.
3670 * The "load" command now supports writing to flash memory, if the remote
3671 stub provides the required support.
3673 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3674 longer requires symbolic debug information (e.g. DWARF-2).
3679 unset substitute-path
3680 show substitute-path
3681 Manage a list of substitution rules that GDB uses to rewrite the name
3682 of the directories where the sources are located. This can be useful
3683 for instance when the sources were moved to a different location
3684 between compilation and debugging.
3688 Print each CLI command as it is executed. Each command is prefixed with
3689 a number of `+' symbols representing the nesting depth.
3690 The source command now has a `-v' option to enable the same feature.
3694 The ARM Demon monitor support (RDP protocol, "target rdp").
3696 Kernel Object Display, an embedded debugging feature which only worked with
3697 an obsolete version of Cisco IOS.
3699 The 'set download-write-size' and 'show download-write-size' commands.
3701 * New remote packets
3704 Tell a stub about GDB client features, and request remote target features.
3705 The first feature implemented is PacketSize, which allows the target to
3706 specify the size of packets it can handle - to minimize the number of
3707 packets required and improve performance when connected to a remote
3711 Fetch an OS auxilliary vector from the remote stub. This packet is a
3712 more efficient replacement for qPart:auxv:read.
3714 qXfer:memory-map:read:
3715 Fetch a memory map from the remote stub, including information about
3716 RAM, ROM, and flash memory devices.
3721 Erase and program a flash memory device.
3723 * Removed remote packets
3726 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3727 used it, and only gdbserver implemented it.
3729 *** Changes in GDB 6.5
3733 Renesas M32C/M16C m32c-elf
3735 Morpho Technologies ms1 ms1-elf
3739 init-if-undefined Initialize a convenience variable, but
3740 only if it doesn't already have a value.
3742 The following commands are presently only implemented for native GNU/Linux:
3744 checkpoint Save a snapshot of the program state.
3746 restart <n> Return the program state to a
3747 previously saved state.
3749 info checkpoints List currently saved checkpoints.
3751 delete-checkpoint <n> Delete a previously saved checkpoint.
3753 set|show detach-on-fork Tell gdb whether to detach from a newly
3754 forked process, or to keep debugging it.
3756 info forks List forks of the user program that
3757 are available to be debugged.
3759 fork <n> Switch to debugging one of several
3760 forks of the user program that are
3761 available to be debugged.
3763 delete-fork <n> Delete a fork from the list of forks
3764 that are available to be debugged (and
3765 kill the forked process).
3767 detach-fork <n> Delete a fork from the list of forks
3768 that are available to be debugged (and
3769 allow the process to continue).
3773 Morpho Technologies ms2 ms1-elf
3775 * Improved Windows host support
3777 GDB now builds as a cross debugger hosted on i686-mingw32, including
3778 native console support, and remote communications using either
3779 network sockets or serial ports.
3781 * Improved Modula-2 language support
3783 GDB can now print most types in the Modula-2 syntax. This includes:
3784 basic types, set types, record types, enumerated types, range types,
3785 pointer types and ARRAY types. Procedure var parameters are correctly
3786 printed and hexadecimal addresses and character constants are also
3787 written in the Modula-2 syntax. Best results can be obtained by using
3788 GNU Modula-2 together with the -gdwarf-2 command line option.
3792 The ARM rdi-share module.
3794 The Netware NLM debug server.
3796 *** Changes in GDB 6.4
3798 * New native configurations
3800 OpenBSD/arm arm*-*-openbsd*
3801 OpenBSD/mips64 mips64-*-openbsd*
3805 Morpho Technologies ms1 ms1-elf
3807 * New command line options
3809 --batch-silent As for --batch, but totally silent.
3810 --return-child-result The debugger will exist with the same value
3811 the child (debugged) program exited with.
3812 --eval-command COMMAND, -ex COMMAND
3813 Execute a single GDB CLI command. This may be
3814 specified multiple times and in conjunction
3815 with the --command (-x) option.
3817 * Deprecated commands removed
3819 The following commands, that were deprecated in 2000, have been
3823 set|show arm disassembly-flavor set|show arm disassembler
3824 othernames set arm disassembler
3825 set|show remotedebug set|show debug remote
3826 set|show archdebug set|show debug arch
3827 set|show eventdebug set|show debug event
3830 * New BSD user-level threads support
3832 It is now possible to debug programs using the user-level threads
3833 library on OpenBSD and FreeBSD. Currently supported (target)
3836 FreeBSD/amd64 x86_64-*-freebsd*
3837 FreeBSD/i386 i386-*-freebsd*
3838 OpenBSD/i386 i386-*-openbsd*
3840 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3841 are not yet supported.
3843 * New support for Matsushita MN10300 w/sim added
3844 (Work in progress). mn10300-elf.
3846 * REMOVED configurations and files
3848 VxWorks and the XDR protocol *-*-vxworks
3849 Motorola MCORE mcore-*-*
3850 National Semiconductor NS32000 ns32k-*-*
3852 * New "set print array-indexes" command
3854 After turning this setting "on", GDB prints the index of each element
3855 when displaying arrays. The default is "off" to preserve the previous
3858 * VAX floating point support
3860 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3862 * User-defined command support
3864 In addition to using $arg0..$arg9 for argument passing, it is now possible
3865 to use $argc to determine now many arguments have been passed. See the
3866 section on user-defined commands in the user manual for more information.
3868 *** Changes in GDB 6.3:
3870 * New command line option
3872 GDB now accepts -l followed by a number to set the timeout for remote
3875 * GDB works with GCC -feliminate-dwarf2-dups
3877 GDB now supports a more compact representation of DWARF-2 debug
3878 information using DW_FORM_ref_addr references. These are produced
3879 by GCC with the option -feliminate-dwarf2-dups and also by some
3880 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3881 to use -feliminate-dwarf2-dups.
3883 * Internationalization
3885 When supported by the host system, GDB will be built with
3886 internationalization (libintl). The task of marking up the sources is
3887 continued, we're looking forward to our first translation.
3891 Initial support for debugging programs compiled with the GNAT
3892 implementation of the Ada programming language has been integrated
3893 into GDB. In this release, support is limited to expression evaluation.
3895 * New native configurations
3897 GNU/Linux/m32r m32r-*-linux-gnu
3901 GDB's remote protocol now includes support for the 'p' packet. This
3902 packet is used to fetch individual registers from a remote inferior.
3904 * END-OF-LIFE registers[] compatibility module
3906 GDB's internal register infrastructure has been completely rewritten.
3907 The new infrastructure making possible the implementation of key new
3908 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3911 GDB 6.3 will be the last release to include the the registers[]
3912 compatibility module that allowed out-of-date configurations to
3913 continue to work. This change directly impacts the following
3923 powerpc bdm protocol
3925 Unless there is activity to revive these configurations, they will be
3926 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3928 * OBSOLETE configurations and files
3930 Configurations that have been declared obsolete in this release have
3931 been commented out. Unless there is activity to revive these
3932 configurations, the next release of GDB will have their sources
3933 permanently REMOVED.
3942 *** Changes in GDB 6.2.1:
3944 * MIPS `break main; run' gave an heuristic-fence-post warning
3946 When attempting to run even a simple program, a warning about
3947 heuristic-fence-post being hit would be reported. This problem has
3950 * MIPS IRIX 'long double' crashed GDB
3952 When examining a long double variable, GDB would get a segmentation
3953 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3954 IRIX long double values).
3958 A bug in the VAX stack code was causing problems with the "next"
3959 command. This problem has been fixed.
3961 *** Changes in GDB 6.2:
3963 * Fix for ``many threads''
3965 On GNU/Linux systems that use the NPTL threads library, a program
3966 rapidly creating and deleting threads would confuse GDB leading to the
3969 ptrace: No such process.
3970 thread_db_get_info: cannot get thread info: generic error
3972 This problem has been fixed.
3974 * "-async" and "-noasync" options removed.
3976 Support for the broken "-noasync" option has been removed (it caused
3979 * New ``start'' command.
3981 This command runs the program until the begining of the main procedure.
3983 * New BSD Kernel Data Access Library (libkvm) interface
3985 Using ``target kvm'' it is now possible to debug kernel core dumps and
3986 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3987 platforms. Currently supported (native-only) configurations are:
3989 FreeBSD/amd64 x86_64-*-freebsd*
3990 FreeBSD/i386 i?86-*-freebsd*
3991 NetBSD/i386 i?86-*-netbsd*
3992 NetBSD/m68k m68*-*-netbsd*
3993 NetBSD/sparc sparc-*-netbsd*
3994 OpenBSD/amd64 x86_64-*-openbsd*
3995 OpenBSD/i386 i?86-*-openbsd*
3996 OpenBSD/m68k m68*-openbsd*
3997 OpenBSD/sparc sparc-*-openbsd*
3999 * Signal trampoline code overhauled
4001 Many generic problems with GDB's signal handling code have been fixed.
4002 These include: backtraces through non-contiguous stacks; recognition
4003 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4004 call; backtrace through a signal trampoline; step into and out of
4005 signal handlers; and single-stepping in the signal trampoline.
4007 Please note that kernel bugs are a limiting factor here. These
4008 features have been shown to work on an s390 GNU/Linux system that
4009 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4011 * Cygwin support for DWARF 2 added.
4013 * New native configurations
4015 GNU/Linux/hppa hppa*-*-linux*
4016 OpenBSD/hppa hppa*-*-openbsd*
4017 OpenBSD/m68k m68*-*-openbsd*
4018 OpenBSD/m88k m88*-*-openbsd*
4019 OpenBSD/powerpc powerpc-*-openbsd*
4020 NetBSD/vax vax-*-netbsd*
4021 OpenBSD/vax vax-*-openbsd*
4023 * END-OF-LIFE frame compatibility module
4025 GDB's internal frame infrastructure has been completely rewritten.
4026 The new infrastructure making it possible to support key new features
4027 including DWARF 2 Call Frame Information. To aid in the task of
4028 migrating old configurations to this new infrastructure, a
4029 compatibility module, that allowed old configurations to continue to
4030 work, was also included.
4032 GDB 6.2 will be the last release to include this frame compatibility
4033 module. This change directly impacts the following configurations:
4043 Unless there is activity to revive these configurations, they will be
4044 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4046 * REMOVED configurations and files
4048 Sun 3, running SunOS 3 m68*-*-sunos3*
4049 Sun 3, running SunOS 4 m68*-*-sunos4*
4050 Sun 2, running SunOS 3 m68000-*-sunos3*
4051 Sun 2, running SunOS 4 m68000-*-sunos4*
4052 Motorola 680x0 running LynxOS m68*-*-lynxos*
4053 AT&T 3b1/Unix pc m68*-att-*
4054 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4055 decstation mips-dec-* mips-little-*
4056 riscos mips-*-riscos* mips-*-sysv*
4057 sonymips mips-sony-*
4058 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4060 *** Changes in GDB 6.1.1:
4062 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4064 The TUI (Text-mode User Interface) is now built as part of a default
4065 GDB configuration. It is enabled by either selecting the TUI with the
4066 command line option "-i=tui" or by running the separate "gdbtui"
4067 program. For more information on the TUI, see the manual "Debugging
4070 * Pending breakpoint support (also included in GDB 6.1)
4072 Support has been added to allow you to specify breakpoints in shared
4073 libraries that have not yet been loaded. If a breakpoint location
4074 cannot be found, and the "breakpoint pending" option is set to auto,
4075 GDB queries you if you wish to make the breakpoint pending on a future
4076 shared-library load. If and when GDB resolves the breakpoint symbol,
4077 the pending breakpoint is removed as one or more regular breakpoints
4080 Pending breakpoints are very useful for GCJ Java debugging.
4082 * Fixed ISO-C build problems
4084 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4085 non ISO-C code that stopped them being built using a more strict ISO-C
4086 compiler (e.g., IBM's C compiler).
4088 * Fixed build problem on IRIX 5
4090 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4091 wasn't able to compile compile on an IRIX 5 system.
4093 * Added execute permission to gdb/gdbserver/configure
4095 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4096 permission. This bug would cause configure to fail on a number of
4097 systems (Solaris, IRIX). Ref: server/519.
4099 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4101 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4102 has been updated to use constant array sizes.
4104 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4106 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4107 its generated DWARF Call Frame Info. This encoding was causing GDB to
4108 panic, that panic has been fixed. Ref: gdb/1628.
4110 * Fixed a problem when examining parameters in shared library code.
4112 When examining parameters in optimized shared library code generated
4113 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4114 not available''. GDB now correctly displays the variable's value.
4116 *** Changes in GDB 6.1:
4118 * Removed --with-mmalloc
4120 Support for the mmalloc memory manager has been removed, as it
4121 conflicted with the internal gdb byte cache.
4123 * Changes in AMD64 configurations
4125 The AMD64 target now includes the %cs and %ss registers. As a result
4126 the AMD64 remote protocol has changed; this affects the floating-point
4127 and SSE registers. If you rely on those registers for your debugging,
4128 you should upgrade gdbserver on the remote side.
4130 * Revised SPARC target
4132 The SPARC target has been completely revised, incorporating the
4133 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4134 support for LynxOS and SunOS 4 has been dropped. Calling functions
4135 from within GDB on operating systems with a non-executable stack
4136 (Solaris, OpenBSD) now works.
4140 GDB has a new C++ demangler which does a better job on the mangled
4141 names generated by current versions of g++. It also runs faster, so
4142 with this and other changes gdb should now start faster on large C++
4145 * DWARF 2 Location Expressions
4147 GDB support for location expressions has been extended to support function
4148 arguments and frame bases. Older versions of GDB could crash when they
4151 * C++ nested types and namespaces
4153 GDB's support for nested types and namespaces in C++ has been
4154 improved, especially if you use the DWARF 2 debugging format. (This
4155 is the default for recent versions of GCC on most platforms.)
4156 Specifically, if you have a class "Inner" defined within a class or
4157 namespace "Outer", then GDB realizes that the class's name is
4158 "Outer::Inner", not simply "Inner". This should greatly reduce the
4159 frequency of complaints about not finding RTTI symbols. In addition,
4160 if you are stopped at inside of a function defined within a namespace,
4161 GDB modifies its name lookup accordingly.
4163 * New native configurations
4165 NetBSD/amd64 x86_64-*-netbsd*
4166 OpenBSD/amd64 x86_64-*-openbsd*
4167 OpenBSD/alpha alpha*-*-openbsd*
4168 OpenBSD/sparc sparc-*-openbsd*
4169 OpenBSD/sparc64 sparc64-*-openbsd*
4171 * New debugging protocols
4173 M32R with SDI protocol m32r-*-elf*
4175 * "set prompt-escape-char" command deleted.
4177 The command "set prompt-escape-char" has been deleted. This command,
4178 and its very obscure effet on GDB's prompt, was never documented,
4179 tested, nor mentioned in the NEWS file.
4181 * OBSOLETE configurations and files
4183 Configurations that have been declared obsolete in this release have
4184 been commented out. Unless there is activity to revive these
4185 configurations, the next release of GDB will have their sources
4186 permanently REMOVED.
4188 Sun 3, running SunOS 3 m68*-*-sunos3*
4189 Sun 3, running SunOS 4 m68*-*-sunos4*
4190 Sun 2, running SunOS 3 m68000-*-sunos3*
4191 Sun 2, running SunOS 4 m68000-*-sunos4*
4192 Motorola 680x0 running LynxOS m68*-*-lynxos*
4193 AT&T 3b1/Unix pc m68*-att-*
4194 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4195 decstation mips-dec-* mips-little-*
4196 riscos mips-*-riscos* mips-*-sysv*
4197 sonymips mips-sony-*
4198 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4200 * REMOVED configurations and files
4202 SGI Irix-4.x mips-sgi-irix4 or iris4
4203 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4204 Z8000 simulator z8k-zilog-none or z8ksim
4205 Matsushita MN10200 w/simulator mn10200-*-*
4206 H8/500 simulator h8500-hitachi-hms or h8500hms
4207 HP/PA running BSD hppa*-*-bsd*
4208 HP/PA running OSF/1 hppa*-*-osf*
4209 HP/PA Pro target hppa*-*-pro*
4210 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4211 386BSD i[3456]86-*-bsd*
4212 Sequent family i[3456]86-sequent-sysv4*
4213 i[3456]86-sequent-sysv*
4214 i[3456]86-sequent-bsd*
4215 SPARC running LynxOS sparc-*-lynxos*
4216 SPARC running SunOS 4 sparc-*-sunos4*
4217 Tsqware Sparclet sparclet-*-*
4218 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4220 *** Changes in GDB 6.0:
4224 Support for debugging the Objective-C programming language has been
4225 integrated into GDB.
4227 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4229 DWARF 2's Call Frame Information makes available compiler generated
4230 information that more exactly describes the program's run-time stack.
4231 By using this information, GDB is able to provide more robust stack
4234 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4235 have been updated to use a new backtrace mechanism which includes
4236 DWARF 2 CFI support.
4240 GDB's remote protocol has been extended to include support for hosted
4241 file I/O (where the remote target uses GDB's file system). See GDB's
4242 remote protocol documentation for details.
4244 * All targets using the new architecture framework.
4246 All of GDB's targets have been updated to use the new internal
4247 architecture framework. The way is now open for future GDB releases
4248 to include cross-architecture native debugging support (i386 on amd64,
4251 * GNU/Linux's Thread Local Storage (TLS)
4253 GDB now includes support for for the GNU/Linux implementation of
4254 per-thread variables.
4256 * GNU/Linux's Native POSIX Thread Library (NPTL)
4258 GDB's thread code has been updated to work with either the new
4259 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4261 * Separate debug info.
4263 GDB, in conjunction with BINUTILS, now supports a mechanism for
4264 automatically loading debug information from a separate file. Instead
4265 of shipping full debug and non-debug versions of system libraries,
4266 system integrators can now instead ship just the stripped libraries
4267 and optional debug files.
4269 * DWARF 2 Location Expressions
4271 DWARF 2 Location Expressions allow the compiler to more completely
4272 describe the location of variables (even in optimized code) to the
4275 GDB now includes preliminary support for location expressions (support
4276 for DW_OP_piece is still missing).
4280 A number of long standing bugs that caused GDB to die while starting a
4281 Java application have been fixed. GDB's Java support is now
4282 considered "useable".
4284 * GNU/Linux support for fork, vfork, and exec.
4286 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4287 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4290 * GDB supports logging output to a file
4292 There are two new commands, "set logging" and "show logging", which can be
4293 used to capture GDB's output to a file.
4295 * The meaning of "detach" has changed for gdbserver
4297 The "detach" command will now resume the application, as documented. To
4298 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4301 * d10v, m68hc11 `regs' command deprecated
4303 The `info registers' command has been updated so that it displays the
4304 registers using a format identical to the old `regs' command.
4308 A new command, "maint set profile on/off", has been added. This command can
4309 be used to enable or disable profiling while running GDB, to profile a
4310 session or a set of commands. In addition there is a new configure switch,
4311 "--enable-profiling", which will cause GDB to be compiled with profiling
4312 data, for more informative profiling results.
4314 * Default MI syntax changed to "mi2".
4316 The default MI (machine interface) syntax, enabled by the command line
4317 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4318 "mi1", can be enabled by specifying the option "-i=mi1".
4320 Support for the original "mi0" syntax (included in GDB 5.0) has been
4323 Fix for gdb/192: removed extraneous space when displaying frame level.
4324 Fix for gdb/672: update changelist is now output in mi list format.
4325 Fix for gdb/702: a -var-assign that updates the value now shows up
4326 in a subsequent -var-update.
4328 * New native configurations.
4330 FreeBSD/amd64 x86_64-*-freebsd*
4332 * Multi-arched targets.
4334 HP/PA HPUX11 hppa*-*-hpux*
4335 Renesas M32R/D w/simulator m32r-*-elf*
4337 * OBSOLETE configurations and files
4339 Configurations that have been declared obsolete in this release have
4340 been commented out. Unless there is activity to revive these
4341 configurations, the next release of GDB will have their sources
4342 permanently REMOVED.
4344 Z8000 simulator z8k-zilog-none or z8ksim
4345 Matsushita MN10200 w/simulator mn10200-*-*
4346 H8/500 simulator h8500-hitachi-hms or h8500hms
4347 HP/PA running BSD hppa*-*-bsd*
4348 HP/PA running OSF/1 hppa*-*-osf*
4349 HP/PA Pro target hppa*-*-pro*
4350 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4351 Sequent family i[3456]86-sequent-sysv4*
4352 i[3456]86-sequent-sysv*
4353 i[3456]86-sequent-bsd*
4354 Tsqware Sparclet sparclet-*-*
4355 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4357 * REMOVED configurations and files
4360 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4361 IBM AIX PS/2 i[3456]86-*-aix
4362 i386 running Mach 3.0 i[3456]86-*-mach3*
4363 i386 running Mach i[3456]86-*-mach*
4364 i386 running OSF/1 i[3456]86-*osf1mk*
4365 HP/Apollo 68k Family m68*-apollo*-sysv*,
4367 m68*-hp-bsd*, m68*-hp-hpux*
4368 Argonaut Risc Chip (ARC) arc-*-*
4369 Mitsubishi D30V d30v-*-*
4370 Fujitsu FR30 fr30-*-elf*
4371 OS/9000 i[34]86-*-os9k
4372 I960 with MON960 i960-*-coff
4374 * MIPS $fp behavior changed
4376 The convenience variable $fp, for the MIPS, now consistently returns
4377 the address of the current frame's base. Previously, depending on the
4378 context, $fp could refer to either $sp or the current frame's base
4379 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4380 The GNU Source-Level Debugger''.
4382 *** Changes in GDB 5.3:
4384 * GNU/Linux shared library multi-threaded performance improved.
4386 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4387 `/proc', in preference to `ptrace' for memory reads. This may result
4388 in an improvement in the start-up time of multi-threaded, shared
4389 library applications when run under GDB. One GDB user writes: ``loads
4390 shared libs like mad''.
4392 * ``gdbserver'' now supports multi-threaded applications on some targets
4394 Support for debugging multi-threaded applications which use
4395 the GNU/Linux LinuxThreads package has been added for
4396 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4397 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4399 * GDB now supports C/C++ preprocessor macros.
4401 GDB now expands preprocessor macro invocations in C/C++ expressions,
4402 and provides various commands for showing macro definitions and how
4405 The new command `macro expand EXPRESSION' expands any macro
4406 invocations in expression, and shows the result.
4408 The new command `show macro MACRO-NAME' shows the definition of the
4409 macro named MACRO-NAME, and where it was defined.
4411 Most compilers don't include information about macros in the debugging
4412 information by default. In GCC 3.1, for example, you need to compile
4413 your program with the options `-gdwarf-2 -g3'. If the macro
4414 information is present in the executable, GDB will read it.
4416 * Multi-arched targets.
4418 DEC Alpha (partial) alpha*-*-*
4419 DEC VAX (partial) vax-*-*
4421 National Semiconductor NS32000 (partial) ns32k-*-*
4422 Motorola 68000 (partial) m68k-*-*
4423 Motorola MCORE mcore-*-*
4427 Fujitsu FRV architecture added by Red Hat frv*-*-*
4430 * New native configurations
4432 Alpha NetBSD alpha*-*-netbsd*
4433 SH NetBSD sh*-*-netbsdelf*
4434 MIPS NetBSD mips*-*-netbsd*
4435 UltraSPARC NetBSD sparc64-*-netbsd*
4437 * OBSOLETE configurations and files
4439 Configurations that have been declared obsolete in this release have
4440 been commented out. Unless there is activity to revive these
4441 configurations, the next release of GDB will have their sources
4442 permanently REMOVED.
4444 Mitsubishi D30V d30v-*-*
4445 OS/9000 i[34]86-*-os9k
4446 IBM AIX PS/2 i[3456]86-*-aix
4447 Fujitsu FR30 fr30-*-elf*
4448 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4449 Argonaut Risc Chip (ARC) arc-*-*
4450 i386 running Mach 3.0 i[3456]86-*-mach3*
4451 i386 running Mach i[3456]86-*-mach*
4452 i386 running OSF/1 i[3456]86-*osf1mk*
4453 HP/Apollo 68k Family m68*-apollo*-sysv*,
4455 m68*-hp-bsd*, m68*-hp-hpux*
4456 I960 with MON960 i960-*-coff
4458 * OBSOLETE languages
4460 CHILL, a Pascal like language used by telecommunications companies.
4462 * REMOVED configurations and files
4464 AMD 29k family via UDI a29k-amd-udi, udi29k
4465 A29K VxWorks a29k-*-vxworks
4466 AMD 29000 embedded, using EBMON a29k-none-none
4467 AMD 29000 embedded with COFF a29k-none-coff
4468 AMD 29000 embedded with a.out a29k-none-aout
4470 testsuite/gdb.hp/gdb.threads-hp/ directory
4472 * New command "set max-user-call-depth <nnn>"
4474 This command allows the user to limit the call depth of user-defined
4475 commands. The default is 1024.
4477 * Changes in FreeBSD/i386 native debugging.
4479 Support for the "generate-core-file" has been added.
4481 * New commands "dump", "append", and "restore".
4483 These commands allow data to be copied from target memory
4484 to a bfd-format or binary file (dump and append), and back
4485 from a file into memory (restore).
4487 * Improved "next/step" support on multi-processor Alpha Tru64.
4489 The previous single-step mechanism could cause unpredictable problems,
4490 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4491 of a software single-step mechanism prevents this.
4493 *** Changes in GDB 5.2.1:
4501 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4502 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4503 Fix, by Joel Brobecker imported from mainline.
4505 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4506 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4507 Fix, by Fred Fish, imported from mainline.
4509 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4510 Surprisingly enough, it works now.
4511 By Michal Ludvig, imported from mainline.
4513 i386 hardware watchpoint support:
4514 avoid misses on second run for some targets.
4515 By Pierre Muller, imported from mainline.
4517 *** Changes in GDB 5.2:
4519 * New command "set trust-readonly-sections on[off]".
4521 This command is a hint that tells gdb that read-only sections
4522 really are read-only (ie. that their contents will not change).
4523 In this mode, gdb will go to the object file rather than the
4524 target to read memory from read-only sections (such as ".text").
4525 This can be a significant performance improvement on some
4526 (notably embedded) targets.
4528 * New command "generate-core-file" (or "gcore").
4530 This new gdb command allows the user to drop a core file of the child
4531 process state at any time. So far it's been implemented only for
4532 GNU/Linux and Solaris, but should be relatively easily ported to other
4533 hosts. Argument is core file name (defaults to core.<pid>).
4535 * New command line option
4537 GDB now accepts --pid or -p followed by a process id.
4539 * Change in command line behavior -- corefiles vs. process ids.
4541 There is a subtle behavior in the way in which GDB handles
4542 command line arguments. The first non-flag argument is always
4543 a program to debug, but the second non-flag argument may either
4544 be a corefile or a process id. Previously, GDB would attempt to
4545 open the second argument as a corefile, and if that failed, would
4546 issue a superfluous error message and then attempt to attach it as
4547 a process. Now, if the second argument begins with a non-digit,
4548 it will be treated as a corefile. If it begins with a digit,
4549 GDB will attempt to attach it as a process, and if no such process
4550 is found, will then attempt to open it as a corefile.
4552 * Changes in ARM configurations.
4554 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4555 configuration is fully multi-arch.
4557 * New native configurations
4559 ARM NetBSD arm*-*-netbsd*
4560 x86 OpenBSD i[3456]86-*-openbsd*
4561 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4562 Sparc64 running FreeBSD sparc64-*-freebsd*
4566 Sanyo XStormy16 xstormy16-elf
4568 * OBSOLETE configurations and files
4570 Configurations that have been declared obsolete in this release have
4571 been commented out. Unless there is activity to revive these
4572 configurations, the next release of GDB will have their sources
4573 permanently REMOVED.
4575 AMD 29k family via UDI a29k-amd-udi, udi29k
4576 A29K VxWorks a29k-*-vxworks
4577 AMD 29000 embedded, using EBMON a29k-none-none
4578 AMD 29000 embedded with COFF a29k-none-coff
4579 AMD 29000 embedded with a.out a29k-none-aout
4581 testsuite/gdb.hp/gdb.threads-hp/ directory
4583 * REMOVED configurations and files
4585 TI TMS320C80 tic80-*-*
4587 PowerPC Solaris powerpcle-*-solaris*
4588 PowerPC Windows NT powerpcle-*-cygwin32
4589 PowerPC Netware powerpc-*-netware*
4590 Harris/CXUX m88k m88*-harris-cxux*
4591 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4592 ns32k-utek-sysv* ns32k-utek-*
4593 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4594 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4595 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4596 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4597 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4599 * Changes to command line processing
4601 The new `--args' feature can be used to specify command-line arguments
4602 for the inferior from gdb's command line.
4604 * Changes to key bindings
4606 There is a new `operate-and-get-next' function bound to `C-o'.
4608 *** Changes in GDB 5.1.1
4610 Fix compile problem on DJGPP.
4612 Fix a problem with floating-point registers on the i386 being
4615 Fix to stop GDB crashing on .debug_str debug info.
4617 Numerous documentation fixes.
4619 Numerous testsuite fixes.
4621 *** Changes in GDB 5.1:
4623 * New native configurations
4625 Alpha FreeBSD alpha*-*-freebsd*
4626 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4627 MIPS GNU/Linux mips*-*-linux*
4628 MIPS SGI Irix 6.x mips*-sgi-irix6*
4629 ia64 AIX ia64-*-aix*
4630 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4634 Motorola 68HC11 and 68HC12 m68hc11-elf
4636 UltraSparc running GNU/Linux sparc64-*-linux*
4638 * OBSOLETE configurations and files
4640 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4641 Harris/CXUX m88k m88*-harris-cxux*
4642 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4643 ns32k-utek-sysv* ns32k-utek-*
4644 TI TMS320C80 tic80-*-*
4646 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4647 PowerPC Solaris powerpcle-*-solaris*
4648 PowerPC Windows NT powerpcle-*-cygwin32
4649 PowerPC Netware powerpc-*-netware*
4650 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4651 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4652 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4653 Apple Macintosh (MPW) host N/A
4655 stuff.c (Program to stuff files into a specially prepared space in kdb)
4656 kdb-start.c (Main loop for the standalone kernel debugger)
4658 Configurations that have been declared obsolete in this release have
4659 been commented out. Unless there is activity to revive these
4660 configurations, the next release of GDB will have their sources
4661 permanently REMOVED.
4663 * REMOVED configurations and files
4665 Altos 3068 m68*-altos-*
4666 Convex c1-*-*, c2-*-*
4668 ARM RISCix arm-*-* (as host)
4672 * GDB has been converted to ISO C.
4674 GDB's source code has been converted to ISO C. In particular, the
4675 sources are fully protoized, and rely on standard headers being
4680 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4682 * The MI enabled by default.
4684 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4685 revised and enabled by default. Packages which use GDB as a debugging
4686 engine behind a UI or another front end are encouraged to switch to
4687 using the GDB/MI interface, instead of the old annotations interface
4688 which is now deprecated.
4690 * Support for debugging Pascal programs.
4692 GDB now includes support for debugging Pascal programs. The following
4693 main features are supported:
4695 - Pascal-specific data types such as sets;
4697 - automatic recognition of Pascal sources based on file-name
4700 - Pascal-style display of data types, variables, and functions;
4702 - a Pascal expression parser.
4704 However, some important features are not yet supported.
4706 - Pascal string operations are not supported at all;
4708 - there are some problems with boolean types;
4710 - Pascal type hexadecimal constants are not supported
4711 because they conflict with the internal variables format;
4713 - support for Pascal objects and classes is not full yet;
4715 - unlike Pascal, GDB is case-sensitive for symbol names.
4717 * Changes in completion.
4719 Commands such as `shell', `run' and `set args', which pass arguments
4720 to inferior programs, now complete on file names, similar to what
4721 users expect at the shell prompt.
4723 Commands which accept locations, such as `disassemble', `print',
4724 `breakpoint', `until', etc. now complete on filenames as well as
4725 program symbols. Thus, if you type "break foob TAB", and the source
4726 files linked into the programs include `foobar.c', that file name will
4727 be one of the candidates for completion. However, file names are not
4728 considered for completion after you typed a colon that delimits a file
4729 name from a name of a function in that file, as in "break foo.c:bar".
4731 `set demangle-style' completes on available demangling styles.
4733 * New platform-independent commands:
4735 It is now possible to define a post-hook for a command as well as a
4736 hook that runs before the command. For more details, see the
4737 documentation of `hookpost' in the GDB manual.
4739 * Changes in GNU/Linux native debugging.
4741 Support for debugging multi-threaded programs has been completely
4742 revised for all platforms except m68k and sparc. You can now debug as
4743 many threads as your system allows you to have.
4745 Attach/detach is supported for multi-threaded programs.
4747 Support for SSE registers was added for x86. This doesn't work for
4748 multi-threaded programs though.
4750 * Changes in MIPS configurations.
4752 Multi-arch support is enabled for all MIPS configurations.
4754 GDB can now be built as native debugger on SGI Irix 6.x systems for
4755 debugging n32 executables. (Debugging 64-bit executables is not yet
4758 * Unified support for hardware watchpoints in all x86 configurations.
4760 Most (if not all) native x86 configurations support hardware-assisted
4761 breakpoints and watchpoints in a unified manner. This support
4762 implements debug register sharing between watchpoints, which allows to
4763 put a virtually infinite number of watchpoints on the same address,
4764 and also supports watching regions up to 16 bytes with several debug
4767 The new maintenance command `maintenance show-debug-regs' toggles
4768 debugging print-outs in functions that insert, remove, and test
4769 watchpoints and hardware breakpoints.
4771 * Changes in the DJGPP native configuration.
4773 New command ``info dos sysinfo'' displays assorted information about
4774 the CPU, OS, memory, and DPMI server.
4776 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4777 display information about segment descriptors stored in GDT, LDT, and
4780 New commands ``info dos pde'' and ``info dos pte'' display entries
4781 from Page Directory and Page Tables (for now works with CWSDPMI only).
4782 New command ``info dos address-pte'' displays the Page Table entry for
4783 a given linear address.
4785 GDB can now pass command lines longer than 126 characters to the
4786 program being debugged (requires an update to the libdbg.a library
4787 which is part of the DJGPP development kit).
4789 DWARF2 debug info is now supported.
4791 It is now possible to `step' and `next' through calls to `longjmp'.
4793 * Changes in documentation.
4795 All GDB documentation was converted to GFDL, the GNU Free
4796 Documentation License.
4798 Tracepoints-related commands are now fully documented in the GDB
4801 TUI, the Text-mode User Interface, is now documented in the manual.
4803 Tracepoints-related commands are now fully documented in the GDB
4806 The "GDB Internals" manual now has an index. It also includes
4807 documentation of `ui_out' functions, GDB coding standards, x86
4808 hardware watchpoints, and memory region attributes.
4810 * GDB's version number moved to ``version.in''
4812 The Makefile variable VERSION has been replaced by the file
4813 ``version.in''. People creating GDB distributions should update the
4814 contents of this file.
4818 GUD support is now a standard part of the EMACS distribution.
4820 *** Changes in GDB 5.0:
4822 * Improved support for debugging FP programs on x86 targets
4824 Unified and much-improved support for debugging floating-point
4825 programs on all x86 targets. In particular, ``info float'' now
4826 displays the FP registers in the same format on all x86 targets, with
4827 greater level of detail.
4829 * Improvements and bugfixes in hardware-assisted watchpoints
4831 It is now possible to watch array elements, struct members, and
4832 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4833 on x86 targets no longer erroneously trigger when the address is
4836 * Improvements in the native DJGPP version of GDB
4838 The distribution now includes all the scripts and auxiliary files
4839 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4840 machines ``out of the box''.
4842 The DJGPP version can now debug programs that use signals. It is
4843 possible to catch signals that happened in the debuggee, deliver
4844 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4845 would kill the program being debugged.) Programs that hook hardware
4846 interrupts (keyboard, timer, etc.) can also be debugged.
4848 It is now possible to debug DJGPP programs that redirect their
4849 standard handles or switch them to raw (as opposed to cooked) mode, or
4850 even close them. The command ``run < foo > bar'' works as expected,
4851 and ``info terminal'' reports useful information about the debuggee's
4852 terminal, including raw/cooked mode, redirection, etc.
4854 The DJGPP version now uses termios functions for console I/O, which
4855 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4858 DOS-style file names with drive letters are now fully supported by
4861 It is now possible to debug DJGPP programs that switch their working
4862 directory. It is also possible to rerun the debuggee any number of
4863 times without restarting GDB; thus, you can use the same setup,
4864 breakpoints, etc. for many debugging sessions.
4866 * New native configurations
4868 ARM GNU/Linux arm*-*-linux*
4869 PowerPC GNU/Linux powerpc-*-linux*
4873 Motorola MCore mcore-*-*
4874 x86 VxWorks i[3456]86-*-vxworks*
4875 PowerPC VxWorks powerpc-*-vxworks*
4876 TI TMS320C80 tic80-*-*
4878 * OBSOLETE configurations
4880 Altos 3068 m68*-altos-*
4881 Convex c1-*-*, c2-*-*
4883 ARM RISCix arm-*-* (as host)
4886 Configurations that have been declared obsolete will be commented out,
4887 but the code will be left in place. If there is no activity to revive
4888 these configurations before the next release of GDB, the sources will
4889 be permanently REMOVED.
4891 * Gould support removed
4893 Support for the Gould PowerNode and NP1 has been removed.
4895 * New features for SVR4
4897 On SVR4 native platforms (such as Solaris), if you attach to a process
4898 without first loading a symbol file, GDB will now attempt to locate and
4899 load symbols from the running process's executable file.
4901 * Many C++ enhancements
4903 C++ support has been greatly improved. Overload resolution now works properly
4904 in almost all cases. RTTI support is on the way.
4906 * Remote targets can connect to a sub-program
4908 A popen(3) style serial-device has been added. This device starts a
4909 sub-process (such as a stand-alone simulator) and then communicates
4910 with that. The sub-program to run is specified using the syntax
4911 ``|<program> <args>'' vis:
4913 (gdb) set remotedebug 1
4914 (gdb) target extended-remote |mn10300-elf-sim program-args
4916 * MIPS 64 remote protocol
4918 A long standing bug in the mips64 remote protocol where by GDB
4919 expected certain 32 bit registers (ex SR) to be transfered as 32
4920 instead of 64 bits has been fixed.
4922 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4923 added to provide backward compatibility with older versions of GDB.
4925 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4927 The command ``set remotebinarydownload'' command has been replaced by
4928 ``set remote X-packet''. Other commands in ``set remote'' family
4929 include ``set remote P-packet''.
4931 * Breakpoint commands accept ranges.
4933 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4934 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4935 ``tracepoint passcount'' also accepts a range of tracepoints.
4937 * ``apropos'' command added.
4939 The ``apropos'' command searches through command names and
4940 documentation strings, printing out matches, making it much easier to
4941 try to find a command that does what you are looking for.
4945 A new machine oriented interface (MI) has been added to GDB. This
4946 interface is designed for debug environments running GDB as a separate
4947 process. This is part of the long term libGDB project. See the
4948 "GDB/MI" chapter of the GDB manual for further information. It can be
4949 enabled by configuring with:
4951 .../configure --enable-gdbmi
4953 *** Changes in GDB-4.18:
4955 * New native configurations
4957 HP-UX 10.20 hppa*-*-hpux10.20
4958 HP-UX 11.x hppa*-*-hpux11.0*
4959 M68K GNU/Linux m68*-*-linux*
4963 Fujitsu FR30 fr30-*-elf*
4964 Intel StrongARM strongarm-*-*
4965 Mitsubishi D30V d30v-*-*
4967 * OBSOLETE configurations
4969 Gould PowerNode, NP1 np1-*-*, pn-*-*
4971 Configurations that have been declared obsolete will be commented out,
4972 but the code will be left in place. If there is no activity to revive
4973 these configurations before the next release of GDB, the sources will
4974 be permanently REMOVED.
4978 As a compatibility experiment, GDB's source files buildsym.h and
4979 buildsym.c have been converted to pure standard C, no longer
4980 containing any K&R compatibility code. We believe that all systems in
4981 use today either come with a standard C compiler, or have a GCC port
4982 available. If this is not true, please report the affected
4983 configuration to bug-gdb@gnu.org immediately. See the README file for
4984 information about getting a standard C compiler if you don't have one
4989 GDB now uses readline 2.2.
4991 * set extension-language
4993 You can now control the mapping between filename extensions and source
4994 languages by using the `set extension-language' command. For instance,
4995 you can ask GDB to treat .c files as C++ by saying
4996 set extension-language .c c++
4997 The command `info extensions' lists all of the recognized extensions
4998 and their associated languages.
5000 * Setting processor type for PowerPC and RS/6000
5002 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5003 you can use the `set processor' command to specify what variant of the
5004 PowerPC family you are debugging. The command
5008 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5009 following PowerPC and RS6000 variants:
5011 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5012 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5014 403GC IBM PowerPC 403GC
5015 505 Motorola PowerPC 505
5016 860 Motorola PowerPC 860 or 850
5017 601 Motorola PowerPC 601
5018 602 Motorola PowerPC 602
5019 603 Motorola/IBM PowerPC 603 or 603e
5020 604 Motorola PowerPC 604 or 604e
5021 750 Motorola/IBM PowerPC 750 or 750
5023 At the moment, this command just tells GDB what to name the
5024 special-purpose processor registers. Since almost all the affected
5025 registers are inaccessible to user-level programs, this command is
5026 only useful for remote debugging in its present form.
5030 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5031 more extensive support for HP-UX. Added features include shared
5032 library support, kernel threads and hardware watchpoints for 11.00,
5033 support for HP's ANSI C and C++ compilers, and a compatibility mode
5034 for xdb and dbx commands.
5038 HP's donation includes the new concept of catchpoints, which is a
5039 generalization of the old catch command. On HP-UX, it is now possible
5040 to catch exec, fork, and vfork, as well as library loading.
5042 This means that the existing catch command has changed; its first
5043 argument now specifies the type of catch to be set up. See the
5044 output of "help catch" for a list of catchpoint types.
5046 * Debugging across forks
5048 On HP-UX, you can choose which process to debug when a fork() happens
5053 HP has donated a curses-based terminal user interface (TUI). To get
5054 it, build with --enable-tui. Although this can be enabled for any
5055 configuration, at present it only works for native HP debugging.
5057 * GDB remote protocol additions
5059 A new protocol packet 'X' that writes binary data is now available.
5060 Default behavior is to try 'X', then drop back to 'M' if the stub
5061 fails to respond. The settable variable `remotebinarydownload'
5062 allows explicit control over the use of 'X'.
5064 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5065 full 64-bit address. The command
5067 set remoteaddresssize 32
5069 can be used to revert to the old behaviour. For existing remote stubs
5070 the change should not be noticed, as the additional address information
5073 In order to assist in debugging stubs, you may use the maintenance
5074 command `packet' to send any text string to the stub. For instance,
5076 maint packet heythere
5078 sends the packet "$heythere#<checksum>". Note that it is very easy to
5079 disrupt a debugging session by sending the wrong packet at the wrong
5082 The compare-sections command allows you to compare section data on the
5083 target to what is in the executable file without uploading or
5084 downloading, by comparing CRC checksums.
5086 * Tracing can collect general expressions
5088 You may now collect general expressions at tracepoints. This requires
5089 further additions to the target-side stub; see tracepoint.c and
5090 doc/agentexpr.texi for further details.
5092 * mask-address variable for Mips
5094 For Mips targets, you may control the zeroing of the upper 32 bits of
5095 a 64-bit address by entering `set mask-address on'. This is mainly
5096 of interest to users of embedded R4xxx and R5xxx processors.
5098 * Higher serial baud rates
5100 GDB's serial code now allows you to specify baud rates 57600, 115200,
5101 230400, and 460800 baud. (Note that your host system may not be able
5102 to achieve all of these rates.)
5106 The i960 configuration now includes an initial implementation of a
5107 builtin simulator, contributed by Jim Wilson.
5110 *** Changes in GDB-4.17:
5112 * New native configurations
5114 Alpha GNU/Linux alpha*-*-linux*
5115 Unixware 2.x i[3456]86-unixware2*
5116 Irix 6.x mips*-sgi-irix6*
5117 PowerPC GNU/Linux powerpc-*-linux*
5118 PowerPC Solaris powerpcle-*-solaris*
5119 Sparc GNU/Linux sparc-*-linux*
5120 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5124 Argonaut Risc Chip (ARC) arc-*-*
5125 Hitachi H8/300S h8300*-*-*
5126 Matsushita MN10200 w/simulator mn10200-*-*
5127 Matsushita MN10300 w/simulator mn10300-*-*
5128 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5129 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5130 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5131 Mitsubishi D10V w/simulator d10v-*-*
5132 Mitsubishi M32R/D w/simulator m32r-*-elf*
5133 Tsqware Sparclet sparclet-*-*
5134 NEC V850 w/simulator v850-*-*
5136 * New debugging protocols
5138 ARM with RDI protocol arm*-*-*
5139 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5140 DDB and LSI variants of PMON protocol mips*-*-*
5141 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5142 PowerPC with SDS protocol powerpc{,le}-*-eabi
5143 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5147 All configurations can now understand and use the DWARF 2 debugging
5148 format. The choice is automatic, if the symbol file contains DWARF 2
5153 GDB now includes basic Java language support. This support is
5154 only useful with Java compilers that produce native machine code.
5156 * solib-absolute-prefix and solib-search-path
5158 For SunOS and SVR4 shared libraries, you may now set the prefix for
5159 loading absolute shared library symbol files, and the search path for
5160 locating non-absolute shared library symbol files.
5162 * Live range splitting
5164 GDB can now effectively debug code for which GCC has performed live
5165 range splitting as part of its optimization. See gdb/doc/LRS for
5166 more details on the expected format of the stabs information.
5170 GDB's support for the GNU Hurd, including thread debugging, has been
5171 updated to work with current versions of the Hurd.
5175 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5176 instruction set. ARM GDB automatically detects when Thumb
5177 instructions are in use, and adjusts disassembly and backtracing
5182 GDB's MIPS target configurations now handle the MIP16 16-bit
5187 GDB now includes support for overlays; if an executable has been
5188 linked such that multiple sections are based at the same address, GDB
5189 will decide which section to use for symbolic info. You can choose to
5190 control the decision manually, using overlay commands, or implement
5191 additional target-side support and use "overlay load-target" to bring
5192 in the overlay mapping. Do "help overlay" for more detail.
5196 The command "info symbol <address>" displays information about
5197 the symbol at the specified address.
5201 The standard remote protocol now includes an extension that allows
5202 asynchronous collection and display of trace data. This requires
5203 extensive support in the target-side debugging stub. Tracing mode
5204 includes a new interaction mode in GDB and new commands: see the
5205 file tracepoint.c for more details.
5209 Configurations for embedded MIPS now include a simulator contributed
5210 by Cygnus Solutions. The simulator supports the instruction sets
5211 of most MIPS variants.
5215 Sparc configurations may now include the ERC32 simulator contributed
5216 by the European Space Agency. The simulator is not built into
5217 Sparc targets by default; configure with --enable-sim to include it.
5221 For target configurations that may include multiple variants of a
5222 basic architecture (such as MIPS and SH), you may now set the
5223 architecture explicitly. "set arch" sets, "info arch" lists
5224 the possible architectures.
5226 *** Changes in GDB-4.16:
5228 * New native configurations
5230 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5231 M68K NetBSD m68k-*-netbsd*
5232 PowerPC AIX 4.x powerpc-*-aix*
5233 PowerPC MacOS powerpc-*-macos*
5234 PowerPC Windows NT powerpcle-*-cygwin32
5235 RS/6000 AIX 4.x rs6000-*-aix4*
5239 ARM with RDP protocol arm-*-*
5240 I960 with MON960 i960-*-coff
5241 MIPS VxWorks mips*-*-vxworks*
5242 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5243 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5245 Matra Sparclet sparclet-*-*
5249 The powerpc-eabi configuration now includes the PSIM simulator,
5250 contributed by Andrew Cagney, with assistance from Mike Meissner.
5251 PSIM is a very elaborate model of the PowerPC, including not only
5252 basic instruction set execution, but also details of execution unit
5253 performance and I/O hardware. See sim/ppc/README for more details.
5257 GDB now works with Solaris 2.5.
5259 * Windows 95/NT native
5261 GDB will now work as a native debugger on Windows 95 and Windows NT.
5262 To build it from source, you must use the "gnu-win32" environment,
5263 which uses a DLL to emulate enough of Unix to run the GNU tools.
5264 Further information, binaries, and sources are available at
5265 ftp.cygnus.com, under pub/gnu-win32.
5267 * dont-repeat command
5269 If a user-defined command includes the command `dont-repeat', then the
5270 command will not be repeated if the user just types return. This is
5271 useful if the command is time-consuming to run, so that accidental
5272 extra keystrokes don't run the same command many times.
5274 * Send break instead of ^C
5276 The standard remote protocol now includes an option to send a break
5277 rather than a ^C to the target in order to interrupt it. By default,
5278 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5280 * Remote protocol timeout
5282 The standard remote protocol includes a new variable `remotetimeout'
5283 that allows you to set the number of seconds before GDB gives up trying
5284 to read from the target. The default value is 2.
5286 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5288 By default GDB will automatically keep track of objects as they are
5289 loaded and unloaded by the dynamic linker. By using the command `set
5290 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5291 when shared library events occur, thus allowing you to set breakpoints
5292 in shared libraries which are explicitly loaded by the inferior.
5294 Note this feature does not work on hpux8. On hpux9 you must link
5295 /usr/lib/end.o into your program. This feature should work
5296 automatically on hpux10.
5298 * Irix 5.x hardware watchpoint support
5300 Irix 5 configurations now support the use of hardware watchpoints.
5302 * Mips protocol "SYN garbage limit"
5304 When debugging a Mips target using the `target mips' protocol, you
5305 may set the number of characters that GDB will ignore by setting
5306 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5307 every character. The default value is 1050.
5309 * Recording and replaying remote debug sessions
5311 If you set `remotelogfile' to the name of a file, gdb will write to it
5312 a recording of a remote debug session. This recording may then be
5313 replayed back to gdb using "gdbreplay". See gdbserver/README for
5314 details. This is useful when you have a problem with GDB while doing
5315 remote debugging; you can make a recording of the session and send it
5316 to someone else, who can then recreate the problem.
5318 * Speedups for remote debugging
5320 GDB includes speedups for downloading and stepping MIPS systems using
5321 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5322 and more efficient S-record downloading.
5324 * Memory use reductions and statistics collection
5326 GDB now uses less memory and reports statistics about memory usage.
5327 Try the `maint print statistics' command, for example.
5329 *** Changes in GDB-4.15:
5331 * Psymtabs for XCOFF
5333 The symbol reader for AIX GDB now uses partial symbol tables. This
5334 can greatly improve startup time, especially for large executables.
5336 * Remote targets use caching
5338 Remote targets now use a data cache to speed up communication with the
5339 remote side. The data cache could lead to incorrect results because
5340 it doesn't know about volatile variables, thus making it impossible to
5341 debug targets which use memory mapped I/O devices. `set remotecache
5342 off' turns the the data cache off.
5344 * Remote targets may have threads
5346 The standard remote protocol now includes support for multiple threads
5347 in the target system, using new protocol commands 'H' and 'T'. See
5348 gdb/remote.c for details.
5352 If GDB is configured with `--enable-netrom', then it will include
5353 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5354 acts as though it is a bank of ROM on the target board, but you can
5355 write into it over the network. GDB's support consists only of
5356 support for fast loading into the emulated ROM; to debug, you must use
5357 another protocol, such as standard remote protocol. The usual
5358 sequence is something like
5360 target nrom <netrom-hostname>
5362 target remote <netrom-hostname>:1235
5366 GDB now includes support for the Apple Macintosh, as a host only. It
5367 may be run as either an MPW tool or as a standalone application, and
5368 it can debug through the serial port. All the usual GDB commands are
5369 available, but to the target command, you must supply "serial" as the
5370 device type instead of "/dev/ttyXX". See mpw-README in the main
5371 directory for more information on how to build. The MPW configuration
5372 scripts */mpw-config.in support only a few targets, and only the
5373 mips-idt-ecoff target has been tested.
5377 GDB configuration now uses autoconf. This is not user-visible,
5378 but does simplify configuration and building.
5382 GDB now supports hpux10.
5384 *** Changes in GDB-4.14:
5386 * New native configurations
5388 x86 FreeBSD i[345]86-*-freebsd
5389 x86 NetBSD i[345]86-*-netbsd
5390 NS32k NetBSD ns32k-*-netbsd
5391 Sparc NetBSD sparc-*-netbsd
5395 A29K VxWorks a29k-*-vxworks
5396 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5397 CPU32 EST-300 emulator m68*-*-est*
5398 PowerPC ELF powerpc-*-elf
5401 * Alpha OSF/1 support for procfs
5403 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5404 possible to attach to running processes. As the mounting of the /proc
5405 filesystem is optional on the Alpha, GDB automatically determines
5406 the availability of /proc during startup. This can lead to problems
5407 if /proc is unmounted after GDB has been started.
5409 * Arguments to user-defined commands
5411 User commands may accept up to 10 arguments separated by whitespace.
5412 Arguments are accessed within the user command via $arg0..$arg9. A
5415 print $arg0 + $arg1 + $arg2
5417 To execute the command use:
5420 Defines the command "adder" which prints the sum of its three arguments.
5421 Note the arguments are text substitutions, so they may reference variables,
5422 use complex expressions, or even perform inferior function calls.
5424 * New `if' and `while' commands
5426 This makes it possible to write more sophisticated user-defined
5427 commands. Both commands take a single argument, which is the
5428 expression to evaluate, and must be followed by the commands to
5429 execute, one per line, if the expression is nonzero, the list being
5430 terminated by the word `end'. The `if' command list may include an
5431 `else' word, which causes the following commands to be executed only
5432 if the expression is zero.
5434 * Fortran source language mode
5436 GDB now includes partial support for Fortran 77. It will recognize
5437 Fortran programs and can evaluate a subset of Fortran expressions, but
5438 variables and functions may not be handled correctly. GDB will work
5439 with G77, but does not yet know much about symbols emitted by other
5442 * Better HPUX support
5444 Most debugging facilities now work on dynamic executables for HPPAs
5445 running hpux9 or later. You can attach to running dynamically linked
5446 processes, but by default the dynamic libraries will be read-only, so
5447 for instance you won't be able to put breakpoints in them. To change
5448 that behavior do the following before running the program:
5454 This will cause the libraries to be mapped private and read-write.
5455 To revert to the normal behavior, do this:
5461 You cannot set breakpoints or examine data in the library until after
5462 the library is loaded if the function/data symbols do not have
5465 GDB can now also read debug symbols produced by the HP C compiler on
5466 HPPAs (sorry, no C++, Fortran or 68k support).
5468 * Target byte order now dynamically selectable
5470 You can choose which byte order to use with a target system, via the
5471 commands "set endian big" and "set endian little", and you can see the
5472 current setting by using "show endian". You can also give the command
5473 "set endian auto", in which case GDB will use the byte order
5474 associated with the executable. Currently, only embedded MIPS
5475 configurations support dynamic selection of target byte order.
5477 * New DOS host serial code
5479 This version uses DPMI interrupts to handle buffered I/O, so you
5480 no longer need to run asynctsr when debugging boards connected to
5483 *** Changes in GDB-4.13:
5485 * New "complete" command
5487 This lists all the possible completions for the rest of the line, if it
5488 were to be given as a command itself. This is intended for use by emacs.
5490 * Trailing space optional in prompt
5492 "set prompt" no longer adds a space for you after the prompt you set. This
5493 allows you to set a prompt which ends in a space or one that does not.
5495 * Breakpoint hit counts
5497 "info break" now displays a count of the number of times the breakpoint
5498 has been hit. This is especially useful in conjunction with "ignore"; you
5499 can ignore a large number of breakpoint hits, look at the breakpoint info
5500 to see how many times the breakpoint was hit, then run again, ignoring one
5501 less than that number, and this will get you quickly to the last hit of
5504 * Ability to stop printing at NULL character
5506 "set print null-stop" will cause GDB to stop printing the characters of
5507 an array when the first NULL is encountered. This is useful when large
5508 arrays actually contain only short strings.
5510 * Shared library breakpoints
5512 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5513 breakpoints in shared libraries before the executable is run.
5515 * Hardware watchpoints
5517 There is a new hardware breakpoint for the watch command for sparclite
5518 targets. See gdb/sparclite/hw_breakpoint.note.
5520 Hardware watchpoints are also now supported under GNU/Linux.
5524 Annotations have been added. These are for use with graphical interfaces,
5525 and are still experimental. Currently only gdba.el uses these.
5527 * Improved Irix 5 support
5529 GDB now works properly with Irix 5.2.
5531 * Improved HPPA support
5533 GDB now works properly with the latest GCC and GAS.
5535 * New native configurations
5537 Sequent PTX4 i[34]86-sequent-ptx4
5538 HPPA running OSF/1 hppa*-*-osf*
5539 Atari TT running SVR4 m68*-*-sysv4*
5540 RS/6000 LynxOS rs6000-*-lynxos*
5544 OS/9000 i[34]86-*-os9k
5545 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5548 * Hitachi SH7000 and E7000-PC ICE support
5550 There is now support for communicating with the Hitachi E7000-PC ICE.
5551 This is available automatically when GDB is configured for the SH.
5555 As usual, a variety of small fixes and improvements, both generic
5556 and configuration-specific. See the ChangeLog for more detail.
5558 *** Changes in GDB-4.12:
5560 * Irix 5 is now supported
5564 GDB-4.12 on the HPPA has a number of changes which make it unable
5565 to debug the output from the currently released versions of GCC and
5566 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5567 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5568 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5571 *** Changes in GDB-4.11:
5573 * User visible changes:
5577 The "set remotedebug" option is now consistent between the mips remote
5578 target, remote targets using the gdb-specific protocol, UDI (AMD's
5579 debug protocol for the 29k) and the 88k bug monitor. It is now an
5580 integer specifying a debug level (normally 0 or 1, but 2 means more
5581 debugging info for the mips target).
5583 * DEC Alpha native support
5585 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5586 debug info, but GDB works fairly well with the DEC compiler and should
5587 work with a future GCC release. See the README file for a few
5588 Alpha-specific notes.
5590 * Preliminary thread implementation
5592 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5594 * LynxOS native and target support for 386
5596 This release has been hosted on LynxOS 2.2, and also can be configured
5597 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5600 * Improvements in C++ mangling/demangling.
5602 This release has much better g++ debugging, specifically in name
5603 mangling/demangling, virtual function calls, print virtual table,
5604 call methods, ...etc.
5606 *** Changes in GDB-4.10:
5608 * User visible changes:
5610 Remote debugging using the GDB-specific (`target remote') protocol now
5611 supports the `load' command. This is only useful if you have some
5612 other way of getting the stub to the target system, and you can put it
5613 somewhere in memory where it won't get clobbered by the download.
5615 Filename completion now works.
5617 When run under emacs mode, the "info line" command now causes the
5618 arrow to point to the line specified. Also, "info line" prints
5619 addresses in symbolic form (as well as hex).
5621 All vxworks based targets now support a user settable option, called
5622 vxworks-timeout. This option represents the number of seconds gdb
5623 should wait for responses to rpc's. You might want to use this if
5624 your vxworks target is, perhaps, a slow software simulator or happens
5625 to be on the far side of a thin network line.
5629 This release contains support for using a DEC alpha as a GDB host for
5630 cross debugging. Native alpha debugging is not supported yet.
5633 *** Changes in GDB-4.9:
5637 This is the first GDB release which is accompanied by a matching testsuite.
5638 The testsuite requires installation of dejagnu, which should be available
5639 via ftp from most sites that carry GNU software.
5643 'Cfront' style demangling has had its name changed to 'ARM' style, to
5644 emphasize that it was written from the specifications in the C++ Annotated
5645 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5646 disclaimers, it still generated too much confusion with users attempting to
5647 use gdb with AT&T cfront.
5651 GDB now uses a standard remote interface to a simulator library.
5652 So far, the library contains simulators for the Zilog Z8001/2, the
5653 Hitachi H8/300, H8/500 and Super-H.
5655 * New targets supported
5657 H8/300 simulator h8300-hitachi-hms or h8300hms
5658 H8/500 simulator h8500-hitachi-hms or h8500hms
5659 SH simulator sh-hitachi-hms or sh
5660 Z8000 simulator z8k-zilog-none or z8ksim
5661 IDT MIPS board over serial line mips-idt-ecoff
5663 Cross-debugging to GO32 targets is supported. It requires a custom
5664 version of the i386-stub.c module which is integrated with the
5665 GO32 memory extender.
5667 * New remote protocols
5669 MIPS remote debugging protocol.
5671 * New source languages supported
5673 This version includes preliminary support for Chill, a Pascal like language
5674 used by telecommunications companies. Chill support is also being integrated
5675 into the GNU compiler, but we don't know when it will be publically available.
5678 *** Changes in GDB-4.8:
5680 * HP Precision Architecture supported
5682 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5683 version of this support was available as a set of patches from the
5684 University of Utah. GDB does not support debugging of programs
5685 compiled with the HP compiler, because HP will not document their file
5686 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5687 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5689 Many problems in the preliminary version have been fixed.
5691 * Faster and better demangling
5693 We have improved template demangling and fixed numerous bugs in the GNU style
5694 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5695 character types (wchar_t) are now supported. Demangling of each symbol is now
5696 only done once, and is cached when the symbol table for a file is read in.
5697 This results in a small increase in memory usage for C programs, a moderate
5698 increase in memory usage for C++ programs, and a fantastic speedup in
5701 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5702 from the specifications in the Annotated Reference Manual, which AT&T's
5703 compiler does not actually implement.
5705 * G++ multiple inheritance compiler problem
5707 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5708 inheritance lattices was reworked to properly discover ambiguities. We
5709 recently found an example which causes this new algorithm to fail in a
5710 very subtle way, producing bad debug information for those classes.
5711 The file 'gcc.patch' (in this directory) can be applied to gcc to
5712 circumvent the problem. A future GCC release will contain a complete
5715 The previous G++ debug info problem (mentioned below for the gdb-4.7
5716 release) is fixed in gcc version 2.3.2.
5718 * Improved configure script
5720 The `configure' script will now attempt to guess your system type if
5721 you don't supply a host system type. The old scheme of supplying a
5722 host system triplet is preferable over using this. All the magic is
5723 done in the new `config.guess' script. Examine it for details.
5725 We have also brought our configure script much more in line with the FSF's
5726 version. It now supports the --with-xxx options. In particular,
5727 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5728 The resulting GDB will not be able to read arbitrary object file formats --
5729 only the format ``expected'' to be used on the configured target system.
5730 We hope to make this the default in a future release.
5732 * Documentation improvements
5734 There's new internal documentation on how to modify GDB, and how to
5735 produce clean changes to the code. We implore people to read it
5736 before submitting changes.
5738 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5739 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5740 `info' files are also provided. To build `info' files from scratch,
5741 you will need the latest `makeinfo' release, which will be available in
5742 a future texinfo-X.Y release.
5744 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5745 We're not sure exactly which versions have this problem, but it has
5746 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5747 or better. If that isn't possible, there is a patch in
5748 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5749 around this problem.
5753 GDB now supports array constants that can be used in expressions typed in by
5754 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5755 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5758 The new directory `gdb/sparclite' contains a program that demonstrates
5759 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5761 * New native hosts supported
5763 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5764 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5766 * New targets supported
5768 AMD 29k family via UDI a29k-amd-udi or udi29k
5770 * New file formats supported
5772 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5773 HPUX core files, and SCO 3.2v2 core files.
5777 Attaching to processes now works again; thanks for the many bug reports.
5779 We have also stomped on a bunch of core dumps caused by
5780 printf_filtered("%s") problems.
5782 We eliminated a copyright problem on the rpc and ptrace header files
5783 for VxWorks, which was discovered at the last minute during the 4.7
5784 release. You should now be able to build a VxWorks GDB.
5786 You can now interrupt gdb while an attached process is running. This
5787 will cause the attached process to stop, and give control back to GDB.
5789 We fixed problems caused by using too many file descriptors
5790 for reading symbols from object files and libraries. This was
5791 especially a problem for programs that used many (~100) shared
5794 The `step' command now only enters a subroutine if there is line number
5795 information for the subroutine. Otherwise it acts like the `next'
5796 command. Previously, `step' would enter subroutines if there was
5797 any debugging information about the routine. This avoids problems
5798 when using `cc -g1' on MIPS machines.
5800 * Internal improvements
5802 GDB's internal interfaces have been improved to make it easier to support
5803 debugging of multiple languages in the future.
5805 GDB now uses a common structure for symbol information internally.
5806 Minimal symbols (derived from linkage symbols in object files), partial
5807 symbols (from a quick scan of debug information), and full symbols
5808 contain a common subset of information, making it easier to write
5809 shared code that handles any of them.
5811 * New command line options
5813 We now accept --silent as an alias for --quiet.
5817 The memory-mapped-malloc library is now licensed under the GNU Library
5818 General Public License.
5820 *** Changes in GDB-4.7:
5822 * Host/native/target split
5824 GDB has had some major internal surgery to untangle the support for
5825 hosts and remote targets. Now, when you configure GDB for a remote
5826 target, it will no longer load in all of the support for debugging
5827 local programs on the host. When fully completed and tested, this will
5828 ensure that arbitrary host/target combinations are possible.
5830 The primary conceptual shift is to separate the non-portable code in
5831 GDB into three categories. Host specific code is required any time GDB
5832 is compiled on that host, regardless of the target. Target specific
5833 code relates to the peculiarities of the target, but can be compiled on
5834 any host. Native specific code is everything else: it can only be
5835 built when the host and target are the same system. Child process
5836 handling and core file support are two common `native' examples.
5838 GDB's use of /proc for controlling Unix child processes is now cleaner.
5839 It has been split out into a single module under the `target_ops' vector,
5840 plus two native-dependent functions for each system that uses /proc.
5842 * New hosts supported
5844 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5845 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5846 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5848 * New targets supported
5850 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5851 68030 and CPU32 m68030-*-*, m68332-*-*
5853 * New native hosts supported
5855 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5856 (386bsd is not well tested yet)
5857 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5859 * New file formats supported
5861 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5862 supports reading of `a.out.adobe' object files, which are an a.out
5863 format extended with minimal information about multiple sections.
5867 `show copying' is the same as the old `info copying'.
5868 `show warranty' is the same as `info warrantee'.
5869 These were renamed for consistency. The old commands continue to work.
5871 `info handle' is a new alias for `info signals'.
5873 You can now define pre-command hooks, which attach arbitrary command
5874 scripts to any command. The commands in the hook will be executed
5875 prior to the user's command. You can also create a hook which will be
5876 executed whenever the program stops. See gdb.texinfo.
5880 We now deal with Cfront style name mangling, and can even extract type
5881 info from mangled symbols. GDB can automatically figure out which
5882 symbol mangling style your C++ compiler uses.
5884 Calling of methods and virtual functions has been improved as well.
5888 The crash that occured when debugging Sun Ansi-C compiled binaries is
5889 fixed. This was due to mishandling of the extra N_SO stabs output
5892 We also finally got Ultrix 4.2 running in house, and fixed core file
5893 support, with help from a dozen people on the net.
5895 John M. Farrell discovered that the reason that single-stepping was so
5896 slow on all of the Mips based platforms (primarily SGI and DEC) was
5897 that we were trying to demangle and lookup a symbol used for internal
5898 purposes on every instruction that was being stepped through. Changing
5899 the name of that symbol so that it couldn't be mistaken for a C++
5900 mangled symbol sped things up a great deal.
5902 Rich Pixley sped up symbol lookups in general by getting much smarter
5903 about when C++ symbol mangling is necessary. This should make symbol
5904 completion (TAB on the command line) much faster. It's not as fast as
5905 we'd like, but it's significantly faster than gdb-4.6.
5909 A new user controllable variable 'call_scratch_address' can
5910 specify the location of a scratch area to be used when GDB
5911 calls a function in the target. This is necessary because the
5912 usual method of putting the scratch area on the stack does not work
5913 in systems that have separate instruction and data spaces.
5915 We integrated changes to support the 29k UDI (Universal Debugger
5916 Interface), but discovered at the last minute that we didn't have all
5917 of the appropriate copyright paperwork. We are working with AMD to
5918 resolve this, and hope to have it available soon.
5922 We have sped up the remote serial line protocol, especially for targets
5923 with lots of registers. It now supports a new `expedited status' ('T')
5924 message which can be used in place of the existing 'S' status message.
5925 This allows the remote stub to send only the registers that GDB
5926 needs to make a quick decision about single-stepping or conditional
5927 breakpoints, eliminating the need to fetch the entire register set for
5928 each instruction being stepped through.
5930 The GDB remote serial protocol now implements a write-through cache for
5931 registers, only re-reading the registers if the target has run.
5933 There is also a new remote serial stub for SPARC processors. You can
5934 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5935 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5936 processor with a serial port.
5940 Configure.in files have become much easier to read and modify. A new
5941 `table driven' format makes it more obvious what configurations are
5942 supported, and what files each one uses.
5946 There is a new opcodes library which will eventually contain all of the
5947 disassembly routines and opcode tables. At present, it only contains
5948 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5949 disassembler (binutils/objdump) to share these routines.
5951 The libiberty library is now copylefted under the GNU Library General
5952 Public License. This allows more liberal use, and was done so libg++
5953 can use it. This makes no difference to GDB, since the Library License
5954 grants all the rights from the General Public License.
5958 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5959 reference to the stabs symbol info used by the debugger. It is (as far
5960 as we know) the only published document on this fascinating topic. We
5961 encourage you to read it, compare it to the stabs information on your
5962 system, and send improvements on the document in general (to
5963 bug-gdb@prep.ai.mit.edu).
5965 And, of course, many bugs have been fixed.
5968 *** Changes in GDB-4.6:
5970 * Better support for C++ function names
5972 GDB now accepts as input the "demangled form" of C++ overloaded function
5973 names and member function names, and can do command completion on such names
5974 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5975 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5976 Make use of command completion, it is your friend.
5978 GDB also now accepts a variety of C++ mangled symbol formats. They are
5979 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5980 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5981 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5982 for the list of formats.
5984 * G++ symbol mangling problem
5986 Recent versions of gcc have a bug in how they emit debugging information for
5987 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5988 directory) can be applied to gcc to fix the problem. Alternatively, if you
5989 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5990 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5991 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5994 * New 'maintenance' command
5996 All of the commands related to hacking GDB internals have been moved out of
5997 the main command set, and now live behind the 'maintenance' command. This
5998 can also be abbreviated as 'mt'. The following changes were made:
6000 dump-me -> maintenance dump-me
6001 info all-breakpoints -> maintenance info breakpoints
6002 printmsyms -> maintenance print msyms
6003 printobjfiles -> maintenance print objfiles
6004 printpsyms -> maintenance print psymbols
6005 printsyms -> maintenance print symbols
6007 The following commands are new:
6009 maintenance demangle Call internal GDB demangler routine to
6010 demangle a C++ link name and prints the result.
6011 maintenance print type Print a type chain for a given symbol
6013 * Change to .gdbinit file processing
6015 We now read the $HOME/.gdbinit file before processing the argv arguments
6016 (e.g. reading symbol files or core files). This allows global parameters to
6017 be set, which will apply during the symbol reading. The ./.gdbinit is still
6018 read after argv processing.
6020 * New hosts supported
6022 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6024 GNU/Linux support i386-unknown-linux or linux
6026 We are also including code to support the HP/PA running BSD and HPUX. This
6027 is almost guaranteed not to work, as we didn't have time to test or build it
6028 for this release. We are including it so that the more adventurous (or
6029 masochistic) of you can play with it. We also had major problems with the
6030 fact that the compiler that we got from HP doesn't support the -g option.
6033 * New targets supported
6035 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6037 * More smarts about finding #include files
6039 GDB now remembers the compilation directory for all include files, and for
6040 all files from which C is generated (like yacc and lex sources). This
6041 greatly improves GDB's ability to find yacc/lex sources, and include files,
6042 especially if you are debugging your program from a directory different from
6043 the one that contains your sources.
6045 We also fixed a bug which caused difficulty with listing and setting
6046 breakpoints in include files which contain C code. (In the past, you had to
6047 try twice in order to list an include file that you hadn't looked at before.)
6049 * Interesting infernals change
6051 GDB now deals with arbitrary numbers of sections, where the symbols for each
6052 section must be relocated relative to that section's landing place in the
6053 target's address space. This work was needed to support ELF with embedded
6054 stabs used by Solaris-2.0.
6056 * Bug fixes (of course!)
6058 There have been loads of fixes for the following things:
6059 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6060 i960, stabs, DOS(GO32), procfs, etc...
6062 See the ChangeLog for details.
6064 *** Changes in GDB-4.5:
6066 * New machines supported (host and target)
6068 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6070 SGI Irix-4.x mips-sgi-irix4 or iris4
6072 * New malloc package
6074 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6075 Mmalloc is capable of handling mutiple heaps of memory. It is also
6076 capable of saving a heap to a file, and then mapping it back in later.
6077 This can be used to greatly speedup the startup of GDB by using a
6078 pre-parsed symbol table which lives in a mmalloc managed heap. For
6079 more details, please read mmalloc/mmalloc.texi.
6083 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6084 'help info proc' for details.
6086 * MIPS ecoff symbol table format
6088 The code that reads MIPS symbol table format is now supported on all hosts.
6089 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6092 * File name changes for MS-DOS
6094 Many files in the config directories have been renamed to make it easier to
6095 support GDB on MS-DOSe systems (which have very restrictive file name
6096 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6097 environment) is close to working but has some remaining problems. Note
6098 that debugging of DOS programs is not supported, due to limitations
6099 in the ``operating system'', but it can be used to host cross-debugging.
6101 * Cross byte order fixes
6103 Many fixes have been made to support cross debugging of Sparc and MIPS
6104 targets from hosts whose byte order differs.
6106 * New -mapped and -readnow options
6108 If memory-mapped files are available on your system through the 'mmap'
6109 system call, you can use the -mapped option on the `file' or
6110 `symbol-file' commands to cause GDB to write the symbols from your
6111 program into a reusable file. If the program you are debugging is
6112 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6113 Future GDB debugging sessions will notice the presence of this file,
6114 and will quickly map in symbol information from it, rather than reading
6115 the symbol table from the executable program. Using the '-mapped'
6116 option in a GDB `file' or `symbol-file' command has the same effect as
6117 starting GDB with the '-mapped' command-line option.
6119 You can cause GDB to read the entire symbol table immediately by using
6120 the '-readnow' option with any of the commands that load symbol table
6121 information (or on the GDB command line). This makes the command
6122 slower, but makes future operations faster.
6124 The -mapped and -readnow options are typically combined in order to
6125 build a `fred.syms' file that contains complete symbol information.
6126 A simple GDB invocation to do nothing but build a `.syms' file for future
6129 gdb -batch -nx -mapped -readnow programname
6131 The `.syms' file is specific to the host machine on which GDB is run.
6132 It holds an exact image of GDB's internal symbol table. It cannot be
6133 shared across multiple host platforms.
6135 * longjmp() handling
6137 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6138 siglongjmp() without losing control. This feature has not yet been ported to
6139 all systems. It currently works on many 386 platforms, all MIPS-based
6140 platforms (SGI, DECstation, etc), and Sun3/4.
6144 Preliminary work has been put in to support the new Solaris OS from Sun. At
6145 this time, it can control and debug processes, but it is not capable of
6150 As always, many many bug fixes. The major areas were with g++, and mipsread.
6151 People using the MIPS-based platforms should experience fewer mysterious
6152 crashes and trashed symbol tables.
6154 *** Changes in GDB-4.4:
6156 * New machines supported (host and target)
6158 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6160 BSD Reno on Vax vax-dec-bsd
6161 Ultrix on Vax vax-dec-ultrix
6163 * New machines supported (target)
6165 AMD 29000 embedded, using EBMON a29k-none-none
6169 GDB continues to improve its handling of C++. `References' work better.
6170 The demangler has also been improved, and now deals with symbols mangled as
6171 per the Annotated C++ Reference Guide.
6173 GDB also now handles `stabs' symbol information embedded in MIPS
6174 `ecoff' symbol tables. Since the ecoff format was not easily
6175 extensible to handle new languages such as C++, this appeared to be a
6176 good way to put C++ debugging info into MIPS binaries. This option
6177 will be supported in the GNU C compiler, version 2, when it is
6180 * New features for SVR4
6182 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6183 shared libraries. Debugging dynamically linked programs should present
6184 only minor differences from debugging statically linked programs.
6186 The `info proc' command will print out information about any process
6187 on an SVR4 system (including the one you are debugging). At the moment,
6188 it prints the address mappings of the process.
6190 If you bring up GDB on another SVR4 system, please send mail to
6191 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6193 * Better dynamic linking support in SunOS
6195 Reading symbols from shared libraries which contain debugging symbols
6196 now works properly. However, there remain issues such as automatic
6197 skipping of `transfer vector' code during function calls, which
6198 make it harder to debug code in a shared library, than to debug the
6199 same code linked statically.
6203 GDB is now using the latest `getopt' routines from the FSF. This
6204 version accepts the -- prefix for options with long names. GDB will
6205 continue to accept the old forms (-option and +option) as well.
6206 Various single letter abbreviations for options have been explicity
6207 added to the option table so that they won't get overshadowed in the
6208 future by other options that begin with the same letter.
6212 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6213 Many assorted bugs have been handled. Many more remain to be handled.
6214 See the various ChangeLog files (primarily in gdb and bfd) for details.
6217 *** Changes in GDB-4.3:
6219 * New machines supported (host and target)
6221 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6222 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6223 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6225 * Almost SCO Unix support
6227 We had hoped to support:
6228 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6229 (except for core file support), but we discovered very late in the release
6230 that it has problems with process groups that render gdb unusable. Sorry
6231 about that. I encourage people to fix it and post the fixes.
6233 * Preliminary ELF and DWARF support
6235 GDB can read ELF object files on System V Release 4, and can handle
6236 debugging records for C, in DWARF format, in ELF files. This support
6237 is preliminary. If you bring up GDB on another SVR4 system, please
6238 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6243 GDB now uses the latest `readline' library. One user-visible change
6244 is that two tabs will list possible command completions, which previously
6245 required typing M-? (meta-question mark, or ESC ?).
6249 The `stepi' bug that many of you noticed has been squashed.
6250 Many bugs in C++ have been handled. Many more remain to be handled.
6251 See the various ChangeLog files (primarily in gdb and bfd) for details.
6253 * State of the MIPS world (in case you wondered):
6255 GDB can understand the symbol tables emitted by the compilers
6256 supplied by most vendors of MIPS-based machines, including DEC. These
6257 symbol tables are in a format that essentially nobody else uses.
6259 Some versions of gcc come with an assembler post-processor called
6260 mips-tfile. This program is required if you want to do source-level
6261 debugging of gcc-compiled programs. I believe FSF does not ship
6262 mips-tfile with gcc version 1, but it will eventually come with gcc
6265 Debugging of g++ output remains a problem. g++ version 1.xx does not
6266 really support it at all. (If you're lucky, you should be able to get
6267 line numbers and stack traces to work, but no parameters or local
6268 variables.) With some work it should be possible to improve the
6271 When gcc version 2 is released, you will have somewhat better luck.
6272 However, even then you will get confusing results for inheritance and
6275 We will eventually provide full debugging of g++ output on
6276 DECstations. This will probably involve some kind of stabs-in-ecoff
6277 encapulation, but the details have not been worked out yet.
6280 *** Changes in GDB-4.2:
6282 * Improved configuration
6284 Only one copy of `configure' exists now, and it is not self-modifying.
6285 Porting BFD is simpler.
6289 The `step' and `next' commands now only stop at the first instruction
6290 of a source line. This prevents the multiple stops that used to occur
6291 in switch statements, for-loops, etc. `Step' continues to stop if a
6292 function that has debugging information is called within the line.
6296 Lots of small bugs fixed. More remain.
6298 * New host supported (not target)
6300 Intel 386 PC clone running Mach i386-none-mach
6303 *** Changes in GDB-4.1:
6305 * Multiple source language support
6307 GDB now has internal scaffolding to handle several source languages.
6308 It determines the type of each source file from its filename extension,
6309 and will switch expression parsing and number formatting to match the
6310 language of the function in the currently selected stack frame.
6311 You can also specifically set the language to be used, with
6312 `set language c' or `set language modula-2'.
6316 GDB now has preliminary support for the GNU Modula-2 compiler,
6317 currently under development at the State University of New York at
6318 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6319 continue through the fall of 1991 and into 1992.
6321 Other Modula-2 compilers are currently not supported, and attempting to
6322 debug programs compiled with them will likely result in an error as the
6323 symbol table is read. Feel free to work on it, though!
6325 There are hooks in GDB for strict type checking and range checking,
6326 in the `Modula-2 philosophy', but they do not currently work.
6330 GDB can now write to executable and core files (e.g. patch
6331 a variable's value). You must turn this switch on, specify
6332 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6333 by assigning a new value to a variable. Modifications take
6336 * Automatic SunOS shared library reading
6338 When you run your program, GDB automatically determines where its
6339 shared libraries (if any) have been loaded, and reads their symbols.
6340 The `share' command is no longer needed. This also works when
6341 examining core files.
6345 You can specify the number of lines that the `list' command shows.
6348 * New machines supported (host and target)
6350 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6351 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6352 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6354 * New hosts supported (not targets)
6356 IBM RT/PC: romp-ibm-aix or rtpc
6358 * New targets supported (not hosts)
6360 AMD 29000 embedded with COFF a29k-none-coff
6361 AMD 29000 embedded with a.out a29k-none-aout
6362 Ultracomputer remote kernel debug a29k-nyu-kern
6364 * New remote interfaces
6370 *** Changes in GDB-4.0:
6374 Wide output is wrapped at good places to make the output more readable.
6376 Gdb now supports cross-debugging from a host machine of one type to a
6377 target machine of another type. Communication with the target system
6378 is over serial lines. The ``target'' command handles connecting to the
6379 remote system; the ``load'' command will download a program into the
6380 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6381 also supports debugging of realtime processes running under VxWorks,
6382 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6383 stub on the target system.
6385 New CPUs supported include the AMD 29000 and Intel 960.
6387 GDB now reads object files and symbol tables via a ``binary file''
6388 library, which allows a single copy of GDB to debug programs of multiple
6389 object file types such as a.out and coff.
6391 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6392 refcard.dvi and refcard.ps are available to format it).
6395 * Control-Variable user interface simplified
6397 All variables that control the operation of the debugger can be set
6398 by the ``set'' command, and displayed by the ``show'' command.
6400 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6401 ``Show prompt'' produces the response:
6402 Gdb's prompt is new-gdb=>.
6404 What follows are the NEW set commands. The command ``help set'' will
6405 print a complete list of old and new set commands. ``help set FOO''
6406 will give a longer description of the variable FOO. ``show'' will show
6407 all of the variable descriptions and their current settings.
6409 confirm on/off: Enables warning questions for operations that are
6410 hard to recover from, e.g. rerunning the program while
6411 it is already running. Default is ON.
6413 editing on/off: Enables EMACS style command line editing
6414 of input. Previous lines can be recalled with
6415 control-P, the current line can be edited with control-B,
6416 you can search for commands with control-R, etc.
6419 history filename NAME: NAME is where the gdb command history
6420 will be stored. The default is .gdb_history,
6421 or the value of the environment variable
6424 history size N: The size, in commands, of the command history. The
6425 default is 256, or the value of the environment variable
6428 history save on/off: If this value is set to ON, the history file will
6429 be saved after exiting gdb. If set to OFF, the
6430 file will not be saved. The default is OFF.
6432 history expansion on/off: If this value is set to ON, then csh-like
6433 history expansion will be performed on
6434 command line input. The default is OFF.
6436 radix N: Sets the default radix for input and output. It can be set
6437 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6438 in the current radix, so "set radix 10" is always a no-op.
6440 height N: This integer value is the number of lines on a page. Default
6441 is 24, the current `stty rows'' setting, or the ``li#''
6442 setting from the termcap entry matching the environment
6445 width N: This integer value is the number of characters on a line.
6446 Default is 80, the current `stty cols'' setting, or the ``co#''
6447 setting from the termcap entry matching the environment
6450 Note: ``set screensize'' is obsolete. Use ``set height'' and
6451 ``set width'' instead.
6453 print address on/off: Print memory addresses in various command displays,
6454 such as stack traces and structure values. Gdb looks
6455 more ``symbolic'' if you turn this off; it looks more
6456 ``machine level'' with it on. Default is ON.
6458 print array on/off: Prettyprint arrays. New convenient format! Default
6461 print demangle on/off: Print C++ symbols in "source" form if on,
6464 print asm-demangle on/off: Same, for assembler level printouts
6467 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6470 * Support for Epoch Environment.
6472 The epoch environment is a version of Emacs v18 with windowing. One
6473 new command, ``inspect'', is identical to ``print'', except that if you
6474 are running in the epoch environment, the value is printed in its own
6478 * Support for Shared Libraries
6480 GDB can now debug programs and core files that use SunOS shared libraries.
6481 Symbols from a shared library cannot be referenced
6482 before the shared library has been linked with the program (this
6483 happens after you type ``run'' and before the function main() is entered).
6484 At any time after this linking (including when examining core files
6485 from dynamically linked programs), gdb reads the symbols from each
6486 shared library when you type the ``sharedlibrary'' command.
6487 It can be abbreviated ``share''.
6489 sharedlibrary REGEXP: Load shared object library symbols for files
6490 matching a unix regular expression. No argument
6491 indicates to load symbols for all shared libraries.
6493 info sharedlibrary: Status of loaded shared libraries.
6498 A watchpoint stops execution of a program whenever the value of an
6499 expression changes. Checking for this slows down execution
6500 tremendously whenever you are in the scope of the expression, but is
6501 quite useful for catching tough ``bit-spreader'' or pointer misuse
6502 problems. Some machines such as the 386 have hardware for doing this
6503 more quickly, and future versions of gdb will use this hardware.
6505 watch EXP: Set a watchpoint (breakpoint) for an expression.
6507 info watchpoints: Information about your watchpoints.
6509 delete N: Deletes watchpoint number N (same as breakpoints).
6510 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6511 enable N: Re-enables watchpoint number N (same as breakpoints).
6514 * C++ multiple inheritance
6516 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6519 * C++ exception handling
6521 Gdb now supports limited C++ exception handling. Besides the existing
6522 ability to breakpoint on an exception handler, gdb can breakpoint on
6523 the raising of an exception (before the stack is peeled back to the
6526 catch FOO: If there is a FOO exception handler in the dynamic scope,
6527 set a breakpoint to catch exceptions which may be raised there.
6528 Multiple exceptions (``catch foo bar baz'') may be caught.
6530 info catch: Lists all exceptions which may be caught in the
6531 current stack frame.
6534 * Minor command changes
6536 The command ``call func (arg, arg, ...)'' now acts like the print
6537 command, except it does not print or save a value if the function's result
6538 is void. This is similar to dbx usage.
6540 The ``up'' and ``down'' commands now always print the frame they end up
6541 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6542 frames without printing.
6544 * New directory command
6546 'dir' now adds directories to the FRONT of the source search path.
6547 The path starts off empty. Source files that contain debug information
6548 about the directory in which they were compiled can be found even
6549 with an empty path; Sun CC and GCC include this information. If GDB can't
6550 find your source file in the current directory, type "dir .".
6552 * Configuring GDB for compilation
6554 For normal use, type ``./configure host''. See README or gdb.texinfo
6557 GDB now handles cross debugging. If you are remotely debugging between
6558 two different machines, type ``./configure host -target=targ''.
6559 Host is the machine where GDB will run; targ is the machine
6560 where the program that you are debugging will run.
projects / external / binutils.git / blob