1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.12
6 * Support for thread names on MS-Windows.
8 GDB now catches and handles the special exception that programs
9 running on MS-Windows use to assign names to threads in the
12 *** Changes in GDB 7.12
14 * GDB and GDBserver now build with a C++ compiler by default.
16 The --enable-build-with-cxx configure option is now enabled by
17 default. One must now explicitly configure with
18 --disable-build-with-cxx in order to build with a C compiler. This
19 option will be removed in a future release.
21 * GDBserver now supports recording btrace without maintaining an active
24 * GDB now supports a negative repeat count in the 'x' command to examine
25 memory backward from the given address. For example:
28 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
29 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
30 (gdb) x/-5i 0x0000000000400580
31 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
32 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
33 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
34 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
35 0x40057b <main(int, char**)+25>:
36 callq 0x400536 <Func1(int, char const*)>
38 * Fortran: Support structures with fields of dynamic types and
39 arrays of dynamic types.
41 * GDB now supports multibit bitfields and enums in target register
44 * New Python-based convenience function $_as_string(val), which returns
45 the textual representation of a value. This function is especially
46 useful to obtain the text label of an enum value.
48 * Intel MPX bound violation handling.
50 Segmentation faults caused by a Intel MPX boundary violation
51 now display the kind of violation (upper or lower), the memory
52 address accessed and the memory bounds, along with the usual
53 signal received and code location.
57 Program received signal SIGSEGV, Segmentation fault
58 Upper bound violation while accessing address 0x7fffffffc3b3
59 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
60 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
62 * Rust language support.
63 GDB now supports debugging programs written in the Rust programming
64 language. See https://www.rust-lang.org/ for more information about
67 * Support for running interpreters on specified input/output devices
69 GDB now supports a new mechanism that allows frontends to provide
70 fully featured GDB console views, as a better alternative to
71 building such views on top of the "-interpreter-exec console"
72 command. See the new "new-ui" command below. With that command,
73 frontends can now start GDB in the traditional command-line mode
74 running in an embedded terminal emulator widget, and create a
75 separate MI interpreter running on a specified i/o device. In this
76 way, GDB handles line editing, history, tab completion, etc. in the
77 console all by itself, and the GUI uses the separate MI interpreter
78 for its own control and synchronization, invisible to the command
81 * The "catch syscall" command catches groups of related syscalls.
83 The "catch syscall" command now supports catching a group of related
84 syscalls using the 'group:' or 'g:' prefix.
89 skip -gfile file-glob-pattern
90 skip -function function
91 skip -rfunction regular-expression
92 A generalized form of the skip command, with new support for
93 glob-style file names and regular expressions for function names.
94 Additionally, a file spec and a function spec may now be combined.
96 maint info line-table REGEXP
97 Display the contents of GDB's internal line table data struture.
100 Run any GDB unit tests that were compiled in.
103 Start a new user interface instance running INTERP as interpreter,
104 using the TTY file for input/output.
108 ** gdb.Breakpoint objects have a new attribute "pending", which
109 indicates whether the breakpoint is pending.
110 ** Three new breakpoint-related events have been added:
111 gdb.breakpoint_created, gdb.breakpoint_modified, and
112 gdb.breakpoint_deleted.
115 Signal ("set") the given MS-Windows event object. This is used in
116 conjunction with the Windows JIT debugging (AeDebug) support, where
117 the OS suspends a crashing process until a debugger can attach to
118 it. Resuming the crashing process, in order to debug it, is done by
121 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
122 was added in GDBserver, including JIT compiling fast tracepoint's
123 conditional expression bytecode into native code.
125 * Support for various remote target protocols and ROM monitors has
128 target m32rsdi Remote M32R debugging over SDI
129 target mips MIPS remote debugging protocol
130 target pmon PMON ROM monitor
131 target ddb NEC's DDB variant of PMON for Vr4300
132 target rockhopper NEC RockHopper variant of PMON
133 target lsi LSI variant of PMO
135 * Support for tracepoints and fast tracepoints on powerpc-linux,
136 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
137 including JIT compiling fast tracepoint's conditional expression
138 bytecode into native code.
140 * MI async record =record-started now includes the method and format used for
141 recording. For example:
143 =record-started,thread-group="i1",method="btrace",format="bts"
147 Andes NDS32 nds32*-*-elf
149 *** Changes in GDB 7.11
151 * GDB now supports debugging kernel-based threads on FreeBSD.
153 * Per-inferior thread numbers
155 Thread numbers are now per inferior instead of global. If you're
156 debugging multiple inferiors, GDB displays thread IDs using a
157 qualified INF_NUM.THR_NUM form. For example:
161 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
162 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
163 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
164 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
166 As consequence, thread numbers as visible in the $_thread
167 convenience variable and in Python's InferiorThread.num attribute
168 are no longer unique between inferiors.
170 GDB now maintains a second thread ID per thread, referred to as the
171 global thread ID, which is the new equivalent of thread numbers in
172 previous releases. See also $_gthread below.
174 For backwards compatibility, MI's thread IDs always refer to global
177 * Commands that accept thread IDs now accept the qualified
178 INF_NUM.THR_NUM form as well. For example:
181 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
184 * In commands that accept a list of thread IDs, you can now refer to
185 all threads of an inferior using a star wildcard. GDB accepts
186 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
187 refer to all threads of the current inferior. For example, "info
190 * You can use "info threads -gid" to display the global thread ID of
193 * The new convenience variable $_gthread holds the global number of
196 * The new convenience variable $_inferior holds the number of the
199 * GDB now displays the ID and name of the thread that hit a breakpoint
200 or received a signal, if your program is multi-threaded. For
203 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
204 Thread 1 "main" received signal SIGINT, Interrupt.
206 * Record btrace now supports non-stop mode.
208 * Support for tracepoints on aarch64-linux was added in GDBserver.
210 * The 'record instruction-history' command now indicates speculative execution
211 when using the Intel Processor Trace recording format.
213 * GDB now allows users to specify explicit locations, bypassing
214 the linespec parser. This feature is also available to GDB/MI
217 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
218 GDB now is able to debug both AArch64 applications and ARM applications
221 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
222 including JIT compiling fast tracepoint's conditional expression bytecode
225 * GDB now supports displaced stepping on AArch64 GNU/Linux.
227 * "info threads", "info inferiors", "info display", "info checkpoints"
228 and "maint info program-spaces" now list the corresponding items in
229 ascending ID order, for consistency with all other "info" commands.
231 * In Ada, the overloads selection menu has been enhanced to display the
232 parameter types and the return types for the matching overloaded subprograms.
236 maint set target-non-stop (on|off|auto)
237 maint show target-non-stop
238 Control whether GDB targets always operate in non-stop mode even if
239 "set non-stop" is "off". The default is "auto", meaning non-stop
240 mode is enabled if supported by the target.
242 maint set bfd-sharing
243 maint show bfd-sharing
244 Control the reuse of bfd objects.
248 Control display of debugging info regarding bfd caching.
252 Control display of debugging info regarding FreeBSD threads.
254 set remote multiprocess-extensions-packet
255 show remote multiprocess-extensions-packet
256 Set/show the use of the remote protocol multiprocess extensions.
258 set remote thread-events
259 show remote thread-events
260 Set/show the use of thread create/exit events.
262 set ada print-signatures on|off
263 show ada print-signatures"
264 Control whether parameter types and return types are displayed in overloads
265 selection menus. It is activaled (@code{on}) by default.
269 Controls the maximum size of memory, in bytes, that GDB will
270 allocate for value contents. Prevents incorrect programs from
271 causing GDB to allocate overly large buffers. Default is 64k.
273 * The "disassemble" command accepts a new modifier: /s.
274 It prints mixed source+disassembly like /m with two differences:
275 - disassembled instructions are now printed in program order, and
276 - and source for all relevant files is now printed.
277 The "/m" option is now considered deprecated: its "source-centric"
278 output hasn't proved useful in practice.
280 * The "record instruction-history" command accepts a new modifier: /s.
281 It behaves exactly like /m and prints mixed source+disassembly.
283 * The "set scheduler-locking" command supports a new mode "replay".
284 It behaves like "off" in record mode and like "on" in replay mode.
286 * Support for various ROM monitors has been removed:
288 target dbug dBUG ROM monitor for Motorola ColdFire
289 target picobug Motorola picobug monitor
290 target dink32 DINK32 ROM monitor for PowerPC
291 target m32r Renesas M32R/D ROM monitor
292 target mon2000 mon2000 ROM monitor
293 target ppcbug PPCBUG ROM monitor for PowerPC
295 * Support for reading/writing memory and extracting values on architectures
296 whose memory is addressable in units of any integral multiple of 8 bits.
301 Indicates that an exec system call was executed.
303 exec-events feature in qSupported
304 The qSupported packet allows GDB to request support for exec
305 events using the new 'gdbfeature' exec-event, and the qSupported
306 response can contain the corresponding 'stubfeature'. Set and
307 show commands can be used to display whether these features are enabled.
310 Equivalent to interrupting with the ^C character, but works in
313 thread created stop reason (T05 create:...)
314 Indicates that the thread was just created and is stopped at entry.
316 thread exit stop reply (w exitcode;tid)
317 Indicates that the thread has terminated.
320 Enables/disables thread create and exit event reporting. For
321 example, this is used in non-stop mode when GDB stops a set of
322 threads and synchronously waits for the their corresponding stop
323 replies. Without exit events, if one of the threads exits, GDB
324 would hang forever not knowing that it should no longer expect a
325 stop for that same thread.
328 Indicates that there are no resumed threads left in the target (all
329 threads are stopped). The remote stub reports support for this stop
330 reply to GDB's qSupported query.
333 Enables/disables catching syscalls from the inferior process.
334 The remote stub reports support for this packet to GDB's qSupported query.
336 syscall_entry stop reason
337 Indicates that a syscall was just called.
339 syscall_return stop reason
340 Indicates that a syscall just returned.
342 * Extended-remote exec events
344 ** GDB now has support for exec events on extended-remote Linux targets.
345 For such targets with Linux kernels 2.5.46 and later, this enables
346 follow-exec-mode and exec catchpoints.
348 set remote exec-event-feature-packet
349 show remote exec-event-feature-packet
350 Set/show the use of the remote exec event feature.
352 * Thread names in remote protocol
354 The reply to qXfer:threads:read may now include a name attribute for each
357 * Target remote mode fork and exec events
359 ** GDB now has support for fork and exec events on target remote mode
360 Linux targets. For such targets with Linux kernels 2.5.46 and later,
361 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
362 fork and exec catchpoints.
364 * Remote syscall events
366 ** GDB now has support for catch syscall on remote Linux targets,
367 currently enabled on x86/x86_64 architectures.
369 set remote catch-syscall-packet
370 show remote catch-syscall-packet
371 Set/show the use of the remote catch syscall feature.
375 ** The -var-set-format command now accepts the zero-hexadecimal
376 format. It outputs data in hexadecimal format with zero-padding on the
381 ** gdb.InferiorThread objects have a new attribute "global_num",
382 which refers to the thread's global thread ID. The existing
383 "num" attribute now refers to the thread's per-inferior number.
384 See "Per-inferior thread numbers" above.
385 ** gdb.InferiorThread objects have a new attribute "inferior", which
386 is the Inferior object the thread belongs to.
388 *** Changes in GDB 7.10
390 * Support for process record-replay and reverse debugging on aarch64*-linux*
391 targets has been added. GDB now supports recording of A64 instruction set
392 including advance SIMD instructions.
394 * Support for Sun's version of the "stabs" debug file format has been removed.
396 * GDB now honors the content of the file /proc/PID/coredump_filter
397 (PID is the process ID) on GNU/Linux systems. This file can be used
398 to specify the types of memory mappings that will be included in a
399 corefile. For more information, please refer to the manual page of
400 "core(5)". GDB also has a new command: "set use-coredump-filter
401 on|off". It allows to set whether GDB will read the content of the
402 /proc/PID/coredump_filter file when generating a corefile.
404 * The "info os" command on GNU/Linux can now display information on
406 "info os cpus" Listing of all cpus/cores on the system
408 * GDB has two new commands: "set serial parity odd|even|none" and
409 "show serial parity". These allows to set or show parity for the
412 * The "info source" command now displays the producer string if it was
413 present in the debug info. This typically includes the compiler version
414 and may include things like its command line arguments.
416 * The "info dll", an alias of the "info sharedlibrary" command,
417 is now available on all platforms.
419 * Directory names supplied to the "set sysroot" commands may be
420 prefixed with "target:" to tell GDB to access shared libraries from
421 the target system, be it local or remote. This replaces the prefix
422 "remote:". The default sysroot has been changed from "" to
423 "target:". "remote:" is automatically converted to "target:" for
424 backward compatibility.
426 * The system root specified by "set sysroot" will be prepended to the
427 filename of the main executable (if reported to GDB as absolute by
428 the operating system) when starting processes remotely, and when
429 attaching to already-running local or remote processes.
431 * GDB now supports automatic location and retrieval of executable
432 files from remote targets. Remote debugging can now be initiated
433 using only a "target remote" or "target extended-remote" command
434 (no "set sysroot" or "file" commands are required). See "New remote
437 * The "dump" command now supports verilog hex format.
439 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
441 * On GNU/Linux, GDB and gdbserver are now able to access executable
442 and shared library files without a "set sysroot" command when
443 attaching to processes running in different mount namespaces from
444 the debugger. This makes it possible to attach to processes in
445 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
446 See "New remote packets" below.
448 * The "tui reg" command now provides completion for all of the
449 available register groups, including target specific groups.
451 * The HISTSIZE environment variable is no longer read when determining
452 the size of GDB's command history. GDB now instead reads the dedicated
453 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
454 disables truncation of command history. Non-numeric values of GDBHISTSIZE
459 ** Memory ports can now be unbuffered.
463 ** gdb.Objfile objects have a new attribute "username",
464 which is the name of the objfile as specified by the user,
465 without, for example, resolving symlinks.
466 ** You can now write frame unwinders in Python.
467 ** gdb.Type objects have a new method "optimized_out",
468 returning optimized out gdb.Value instance of this type.
469 ** gdb.Value objects have new methods "reference_value" and
470 "const_value" which return a reference to the value and a
471 "const" version of the value respectively.
475 maint print symbol-cache
476 Print the contents of the symbol cache.
478 maint print symbol-cache-statistics
479 Print statistics of symbol cache usage.
481 maint flush-symbol-cache
482 Flush the contents of the symbol cache.
486 Start branch trace recording using Branch Trace Store (BTS) format.
489 Evaluate expression by using the compiler and print result.
493 Explicit commands for enabling and disabling tui mode.
496 set mpx bound on i386 and amd64
497 Support for bound table investigation on Intel MPX enabled applications.
501 Start branch trace recording using Intel Processor Trace format.
504 Print information about branch tracing internals.
506 maint btrace packet-history
507 Print the raw branch tracing data.
509 maint btrace clear-packet-history
510 Discard the stored raw branch tracing data.
513 Discard all branch tracing data. It will be fetched and processed
514 anew by the next "record" command.
519 Renamed from "set debug dwarf2-die".
521 Renamed from "show debug dwarf2-die".
524 Renamed from "set debug dwarf2-read".
525 show debug dwarf-read
526 Renamed from "show debug dwarf2-read".
528 maint set dwarf always-disassemble
529 Renamed from "maint set dwarf2 always-disassemble".
530 maint show dwarf always-disassemble
531 Renamed from "maint show dwarf2 always-disassemble".
533 maint set dwarf max-cache-age
534 Renamed from "maint set dwarf2 max-cache-age".
535 maint show dwarf max-cache-age
536 Renamed from "maint show dwarf2 max-cache-age".
539 show debug dwarf-line
540 Control display of debugging info regarding DWARF line processing.
544 Set the maximum number of candidates to be considered during
545 completion. The default value is 200. This limit allows GDB
546 to avoid generating large completion lists, the computation of
547 which can cause the debugger to become temporarily unresponsive.
549 set history remove-duplicates
550 show history remove-duplicates
551 Control the removal of duplicate history entries.
553 maint set symbol-cache-size
554 maint show symbol-cache-size
555 Control the size of the symbol cache.
557 set|show record btrace bts buffer-size
558 Set and show the size of the ring buffer used for branch tracing in
560 The obtained size may differ from the requested size. Use "info
561 record" to see the obtained buffer size.
563 set debug linux-namespaces
564 show debug linux-namespaces
565 Control display of debugging info regarding Linux namespaces.
567 set|show record btrace pt buffer-size
568 Set and show the size of the ring buffer used for branch tracing in
569 Intel Processor Trace format.
570 The obtained size may differ from the requested size. Use "info
571 record" to see the obtained buffer size.
573 maint set|show btrace pt skip-pad
574 Set and show whether PAD packets are skipped when computing the
577 * The command 'thread apply all' can now support new option '-ascending'
578 to call its specified command for all threads in ascending order.
580 * Python/Guile scripting
582 ** GDB now supports auto-loading of Python/Guile scripts contained in the
583 special section named `.debug_gdb_scripts'.
587 qXfer:btrace-conf:read
588 Return the branch trace configuration for the current thread.
590 Qbtrace-conf:bts:size
591 Set the requested ring buffer size for branch tracing in BTS format.
594 Enable Intel Procesor Trace-based branch tracing for the current
595 process. The remote stub reports support for this packet to GDB's
599 Set the requested ring buffer size for branch tracing in Intel Processor
603 Indicates a memory breakpoint instruction was executed, irrespective
604 of whether it was GDB that planted the breakpoint or the breakpoint
605 is hardcoded in the program. This is required for correct non-stop
609 Indicates the target stopped for a hardware breakpoint. This is
610 required for correct non-stop mode operation.
613 Return information about files on the remote system.
616 Return the full absolute name of the file that was executed to
617 create a process running on the remote system.
620 Select the filesystem on which vFile: operations with filename
621 arguments will operate. This is required for GDB to be able to
622 access files on remote targets where the remote stub does not
623 share a common filesystem with the inferior(s).
626 Indicates that a fork system call was executed.
629 Indicates that a vfork system call was executed.
631 vforkdone stop reason
632 Indicates that a vfork child of the specified process has executed
633 an exec or exit, allowing the vfork parent to resume execution.
635 fork-events and vfork-events features in qSupported
636 The qSupported packet allows GDB to request support for fork and
637 vfork events using new 'gdbfeatures' fork-events and vfork-events,
638 and the qSupported response can contain the corresponding
639 'stubfeatures'. Set and show commands can be used to display
640 whether these features are enabled.
642 * Extended-remote fork events
644 ** GDB now has support for fork events on extended-remote Linux
645 targets. For targets with Linux kernels 2.5.60 and later, this
646 enables follow-fork-mode and detach-on-fork for both fork and
647 vfork, as well as fork and vfork catchpoints.
649 * The info record command now shows the recording format and the
650 branch tracing configuration for the current thread when using
651 the btrace record target.
652 For the BTS format, it shows the ring buffer size.
654 * GDB now has support for DTrace USDT (Userland Static Defined
655 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
657 * GDB now supports access to vector registers on S/390 GNU/Linux
660 * Removed command line options
662 -xdb HP-UX XDB compatibility mode.
664 * Removed targets and native configurations
666 HP/PA running HP-UX hppa*-*-hpux*
667 Itanium running HP-UX ia64-*-hpux*
669 * New configure options
672 This configure option allows the user to build GDB with support for
673 Intel Processor Trace (default: auto). This requires libipt.
675 --with-libipt-prefix=PATH
676 Specify the path to the version of libipt that GDB should use.
677 $PATH/include should contain the intel-pt.h header and
678 $PATH/lib should contain the libipt.so library.
680 *** Changes in GDB 7.9.1
684 ** Xmethods can now specify a result type.
686 *** Changes in GDB 7.9
688 * GDB now supports hardware watchpoints on x86 GNU Hurd.
692 ** You can now access frame registers from Python scripts.
693 ** New attribute 'producer' for gdb.Symtab objects.
694 ** gdb.Objfile objects have a new attribute "progspace",
695 which is the gdb.Progspace object of the containing program space.
696 ** gdb.Objfile objects have a new attribute "owner".
697 ** gdb.Objfile objects have a new attribute "build_id",
698 which is the build ID generated when the file was built.
699 ** gdb.Objfile objects have a new method "add_separate_debug_file".
700 ** A new event "gdb.clear_objfiles" has been added, triggered when
701 selecting a new file to debug.
702 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
703 ** New function gdb.lookup_objfile.
705 New events which are triggered when GDB modifies the state of the
708 ** gdb.events.inferior_call_pre: Function call is about to be made.
709 ** gdb.events.inferior_call_post: Function call has just been made.
710 ** gdb.events.memory_changed: A memory location has been altered.
711 ** gdb.events.register_changed: A register has been altered.
713 * New Python-based convenience functions:
715 ** $_caller_is(name [, number_of_frames])
716 ** $_caller_matches(regexp [, number_of_frames])
717 ** $_any_caller_is(name [, number_of_frames])
718 ** $_any_caller_matches(regexp [, number_of_frames])
720 * GDB now supports the compilation and injection of source code into
721 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
722 to compile the source code to object code, and if successful, inject
723 and execute that code within the current context of the inferior.
724 Currently the C language is supported. The commands used to
725 interface with this new feature are:
727 compile code [-raw|-r] [--] [source code]
728 compile file [-raw|-r] filename
732 demangle [-l language] [--] name
733 Demangle "name" in the specified language, or the current language
734 if elided. This command is renamed from the "maint demangle" command.
735 The latter is kept as a no-op to avoid "maint demangle" being interpreted
736 as "maint demangler-warning".
738 queue-signal signal-name-or-number
739 Queue a signal to be delivered to the thread when it is resumed.
741 add-auto-load-scripts-directory directory
742 Add entries to the list of directories from which to load auto-loaded
745 maint print user-registers
746 List all currently available "user" registers.
748 compile code [-r|-raw] [--] [source code]
749 Compile, inject, and execute in the inferior the executable object
750 code produced by compiling the provided source code.
752 compile file [-r|-raw] filename
753 Compile and inject into the inferior the executable object code
754 produced by compiling the source code stored in the filename
757 * On resume, GDB now always passes the signal the program had stopped
758 for to the thread the signal was sent to, even if the user changed
759 threads before resuming. Previously GDB would often (but not
760 always) deliver the signal to the thread that happens to be current
763 * Conversely, the "signal" command now consistently delivers the
764 requested signal to the current thread. GDB now asks for
765 confirmation if the program had stopped for a signal and the user
766 switched threads meanwhile.
768 * "breakpoint always-inserted" modes "off" and "auto" merged.
770 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
771 won't remove breakpoints from the target until all threads stop,
772 even in non-stop mode. The "auto" mode has been removed, and "off"
773 is now the default mode.
777 set debug symbol-lookup
778 show debug symbol-lookup
779 Control display of debugging info regarding symbol lookup.
783 ** The -list-thread-groups command outputs an exit-code field for
784 inferiors that have exited.
788 MIPS SDE mips*-sde*-elf*
792 Support for these obsolete configurations has been removed.
794 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
795 SGI Irix-5.x mips-*-irix5*
796 SGI Irix-6.x mips-*-irix6*
797 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
798 VAX running Ultrix vax-*-ultrix*
800 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
801 and "assf"), have been removed. Use the "sharedlibrary" command, or
802 its alias "share", instead.
804 *** Changes in GDB 7.8
806 * New command line options
809 This is an alias for the --data-directory option.
811 * GDB supports printing and modifying of variable length automatic arrays
812 as specified in ISO C99.
814 * The ARM simulator now supports instruction level tracing
815 with or without disassembly.
819 GDB now has support for scripting using Guile. Whether this is
820 available is determined at configure time.
821 Guile version 2.0 or greater is required.
822 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
824 * New commands (for set/show, see "New options" below)
828 Invoke CODE by passing it to the Guile interpreter.
832 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
834 info auto-load guile-scripts [regexp]
835 Print the list of automatically loaded Guile scripts.
837 * The source command is now capable of sourcing Guile scripts.
838 This feature is dependent on the debugger being built with Guile support.
842 set print symbol-loading (off|brief|full)
843 show print symbol-loading
844 Control whether to print informational messages when loading symbol
845 information for a file. The default is "full", but when debugging
846 programs with large numbers of shared libraries the amount of output
849 set guile print-stack (none|message|full)
850 show guile print-stack
851 Show a stack trace when an error is encountered in a Guile script.
853 set auto-load guile-scripts (on|off)
854 show auto-load guile-scripts
855 Control auto-loading of Guile script files.
857 maint ada set ignore-descriptive-types (on|off)
858 maint ada show ignore-descriptive-types
859 Control whether the debugger should ignore descriptive types in Ada
860 programs. The default is not to ignore the descriptive types. See
861 the user manual for more details on descriptive types and the intended
862 usage of this option.
864 set auto-connect-native-target
866 Control whether GDB is allowed to automatically connect to the
867 native target for the run, attach, etc. commands when not connected
868 to any target yet. See also "target native" below.
870 set record btrace replay-memory-access (read-only|read-write)
871 show record btrace replay-memory-access
872 Control what memory accesses are allowed during replay.
874 maint set target-async (on|off)
875 maint show target-async
876 This controls whether GDB targets operate in synchronous or
877 asynchronous mode. Normally the default is asynchronous, if it is
878 available; but this can be changed to more easily debug problems
879 occurring only in synchronous mode.
881 set mi-async (on|off)
883 Control whether MI asynchronous mode is preferred. This supersedes
884 "set target-async" of previous GDB versions.
886 * "set target-async" is deprecated as a CLI option and is now an alias
887 for "set mi-async" (only puts MI into async mode).
889 * Background execution commands (e.g., "c&", "s&", etc.) are now
890 possible ``out of the box'' if the target supports them. Previously
891 the user would need to explicitly enable the possibility with the
892 "set target-async on" command.
894 * New features in the GDB remote stub, GDBserver
896 ** New option --debug-format=option1[,option2,...] allows one to add
897 additional text to each output. At present only timestamps
898 are supported: --debug-format=timestamps.
899 Timestamps can also be turned on with the
900 "monitor set debug-format timestamps" command from GDB.
902 * The 'record instruction-history' command now starts counting instructions
903 at one. This also affects the instruction ranges reported by the
904 'record function-call-history' command when given the /i modifier.
906 * The command 'record function-call-history' supports a new modifier '/c' to
907 indent the function names based on their call stack depth.
908 The fields for the '/i' and '/l' modifier have been reordered.
909 The source line range is now prefixed with 'at'.
910 The instruction range is now prefixed with 'inst'.
911 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
912 "record instruction-history" and "list" commands.
914 * The ranges given as arguments to the 'record function-call-history' and
915 'record instruction-history' commands are now inclusive.
917 * The btrace record target now supports the 'record goto' command.
918 For locations inside the execution trace, the back trace is computed
919 based on the information stored in the execution trace.
921 * The btrace record target supports limited reverse execution and replay.
922 The target does not record data and therefore does not allow reading
925 * The "catch syscall" command now works on s390*-linux* targets.
927 * The "compare-sections" command is no longer specific to target
928 remote. It now works with all targets.
930 * All native targets are now consistently called "native".
931 Consequently, the "target child", "target GNU", "target djgpp",
932 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
933 commands have been replaced with "target native". The QNX/NTO port
934 leaves the "procfs" target in place and adds a "native" target for
935 consistency with other ports. The impact on users should be minimal
936 as these commands previously either throwed an error, or were
937 no-ops. The target's name is visible in the output of the following
938 commands: "help target", "info target", "info files", "maint print
941 * The "target native" command now connects to the native target. This
942 can be used to launch native programs even when "set
943 auto-connect-native-target" is set to off.
945 * GDB now supports access to Intel MPX registers on GNU/Linux.
947 * Support for Intel AVX-512 registers on GNU/Linux.
948 Support displaying and modifying Intel AVX-512 registers
949 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
953 qXfer:btrace:read's annex
954 The qXfer:btrace:read packet supports a new annex 'delta' to read
955 branch trace incrementally.
959 ** Valid Python operations on gdb.Value objects representing
960 structs/classes invoke the corresponding overloaded operators if
962 ** New `Xmethods' feature in the Python API. Xmethods are
963 additional methods or replacements for existing methods of a C++
964 class. This feature is useful for those cases where a method
965 defined in C++ source code could be inlined or optimized out by
966 the compiler, making it unavailable to GDB.
969 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
971 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
972 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
973 its alias "share", instead.
975 * The commands "set remotebaud" and "show remotebaud" are no longer
976 supported. Use "set serial baud" and "show serial baud" (respectively)
981 ** A new option "-gdb-set mi-async" replaces "-gdb-set
982 target-async". The latter is left as a deprecated alias of the
983 former for backward compatibility. If the target supports it,
984 CLI background execution commands are now always possible by
985 default, independently of whether the frontend stated a
986 preference for asynchronous execution with "-gdb-set mi-async".
987 Previously "-gdb-set target-async off" affected both MI execution
988 commands and CLI execution commands.
990 *** Changes in GDB 7.7
992 * Improved support for process record-replay and reverse debugging on
993 arm*-linux* targets. Support for thumb32 and syscall instruction
994 recording has been added.
996 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
998 * GDB now supports Fission DWP file format version 2.
999 http://gcc.gnu.org/wiki/DebugFission
1001 * New convenience function "$_isvoid", to check whether an expression
1002 is void. A void expression is an expression where the type of the
1003 result is "void". For example, some convenience variables may be
1004 "void" when evaluated (e.g., "$_exitcode" before the execution of
1005 the program being debugged; or an undefined convenience variable).
1006 Another example, when calling a function whose return type is
1009 * The "maintenance print objfiles" command now takes an optional regexp.
1011 * The "catch syscall" command now works on arm*-linux* targets.
1013 * GDB now consistently shows "<not saved>" when printing values of
1014 registers the debug info indicates have not been saved in the frame
1015 and there's nowhere to retrieve them from
1016 (callee-saved/call-clobbered registers):
1021 (gdb) info registers rax
1024 Before, the former would print "<optimized out>", and the latter
1025 "*value not available*".
1027 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1032 ** Frame filters and frame decorators have been added.
1033 ** Temporary breakpoints are now supported.
1034 ** Line tables representation has been added.
1035 ** New attribute 'parent_type' for gdb.Field objects.
1036 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1037 ** New attribute 'name' for gdb.Type objects.
1041 Nios II ELF nios2*-*-elf
1042 Nios II GNU/Linux nios2*-*-linux
1043 Texas Instruments MSP430 msp430*-*-elf
1045 * Removed native configurations
1047 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1048 been removed. ELF variants of these configurations are kept supported.
1050 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1051 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1052 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1053 i[34567]86-*-openbsd3.[0-3]
1054 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1055 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1056 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1060 Like "catch throw", but catches a re-thrown exception.
1061 maint check-psymtabs
1062 Renamed from old "maint check-symtabs".
1064 Perform consistency checks on symtabs.
1065 maint expand-symtabs
1066 Expand symtabs matching an optional regexp.
1069 Display the details of GDB configure-time options.
1071 maint set|show per-command
1072 maint set|show per-command space
1073 maint set|show per-command time
1074 maint set|show per-command symtab
1075 Enable display of per-command gdb resource usage.
1077 remove-symbol-file FILENAME
1078 remove-symbol-file -a ADDRESS
1079 Remove a symbol file added via add-symbol-file. The file to remove
1080 can be identified by its filename or by an address that lies within
1081 the boundaries of this symbol file in memory.
1084 info exceptions REGEXP
1085 Display the list of Ada exceptions defined in the program being
1086 debugged. If provided, only the exceptions whose names match REGEXP
1091 set debug symfile off|on
1093 Control display of debugging info regarding reading symbol files and
1094 symbol tables within those files
1096 set print raw frame-arguments
1097 show print raw frame-arguments
1098 Set/show whether to print frame arguments in raw mode,
1099 disregarding any defined pretty-printers.
1101 set remote trace-status-packet
1102 show remote trace-status-packet
1103 Set/show the use of remote protocol qTStatus packet.
1107 Control display of debugging messages related to Nios II targets.
1111 Control whether target-assisted range stepping is enabled.
1113 set startup-with-shell
1114 show startup-with-shell
1115 Specifies whether Unix child processes are started via a shell or
1120 Use the target memory cache for accesses to the code segment. This
1121 improves performance of remote debugging (particularly disassembly).
1123 * You can now use a literal value 'unlimited' for options that
1124 interpret 0 or -1 as meaning "unlimited". E.g., "set
1125 trace-buffer-size unlimited" is now an alias for "set
1126 trace-buffer-size -1" and "set height unlimited" is now an alias for
1129 * The "set debug symtab-create" debugging option of GDB has been changed to
1130 accept a verbosity level. 0 means "off", 1 provides basic debugging
1131 output, and values of 2 or greater provides more verbose output.
1133 * New command-line options
1135 Display the details of GDB configure-time options.
1137 * The command 'tsave' can now support new option '-ctf' to save trace
1138 buffer in Common Trace Format.
1140 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1143 * GDB now implements the the C++ 'typeid' operator.
1145 * The new convenience variable $_exception holds the exception being
1146 thrown or caught at an exception-related catchpoint.
1148 * The exception-related catchpoints, like "catch throw", now accept a
1149 regular expression which can be used to filter exceptions by type.
1151 * The new convenience variable $_exitsignal is automatically set to
1152 the terminating signal number when the program being debugged dies
1153 due to an uncaught signal.
1157 ** All MI commands now accept an optional "--language" option.
1158 Support for this feature can be verified by using the "-list-features"
1159 command, which should contain "language-option".
1161 ** The new command -info-gdb-mi-command allows the user to determine
1162 whether a GDB/MI command is supported or not.
1164 ** The "^error" result record returned when trying to execute an undefined
1165 GDB/MI command now provides a variable named "code" whose content is the
1166 "undefined-command" error code. Support for this feature can be verified
1167 by using the "-list-features" command, which should contain
1168 "undefined-command-error-code".
1170 ** The -trace-save MI command can optionally save trace buffer in Common
1173 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1175 ** The command -data-list-register-values now accepts an optional
1176 "--skip-unavailable" option. When used, only the available registers
1179 ** The new command -trace-frame-collected dumps collected variables,
1180 computed expressions, tvars, memory and registers in a traceframe.
1182 ** The commands -stack-list-locals, -stack-list-arguments and
1183 -stack-list-variables now accept an option "--skip-unavailable".
1184 When used, only the available locals or arguments are displayed.
1186 ** The -exec-run command now accepts an optional "--start" option.
1187 When used, the command follows the same semantics as the "start"
1188 command, stopping the program's execution at the start of its
1189 main subprogram. Support for this feature can be verified using
1190 the "-list-features" command, which should contain
1191 "exec-run-start-option".
1193 ** The new commands -catch-assert and -catch-exceptions insert
1194 catchpoints stopping the program when Ada exceptions are raised.
1196 ** The new command -info-ada-exceptions provides the equivalent of
1197 the new "info exceptions" command.
1199 * New system-wide configuration scripts
1200 A GDB installation now provides scripts suitable for use as system-wide
1201 configuration scripts for the following systems:
1205 * GDB now supports target-assigned range stepping with remote targets.
1206 This improves the performance of stepping source lines by reducing
1207 the number of control packets from/to GDB. See "New remote packets"
1210 * GDB now understands the element 'tvar' in the XML traceframe info.
1211 It has the id of the collected trace state variables.
1213 * On S/390 targets that provide the transactional-execution feature,
1214 the program interruption transaction diagnostic block (TDB) is now
1215 represented as a number of additional "registers" in GDB.
1217 * New remote packets
1221 The vCont packet supports a new 'r' action, that tells the remote
1222 stub to step through an address range itself, without GDB
1223 involvemement at each single-step.
1225 qXfer:libraries-svr4:read's annex
1226 The previously unused annex of the qXfer:libraries-svr4:read packet
1227 is now used to support passing an argument list. The remote stub
1228 reports support for this argument list to GDB's qSupported query.
1229 The defined arguments are "start" and "prev", used to reduce work
1230 necessary for library list updating, resulting in significant
1233 * New features in the GDB remote stub, GDBserver
1235 ** GDBserver now supports target-assisted range stepping. Currently
1236 enabled on x86/x86_64 GNU/Linux targets.
1238 ** GDBserver now adds element 'tvar' in the XML in the reply to
1239 'qXfer:traceframe-info:read'. It has the id of the collected
1240 trace state variables.
1242 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1245 * New 'z' formatter for printing and examining memory, this displays the
1246 value as hexadecimal zero padded on the left to the size of the type.
1248 * GDB can now use Windows x64 unwinding data.
1250 * The "set remotebaud" command has been replaced by "set serial baud".
1251 Similarly, "show remotebaud" has been replaced by "show serial baud".
1252 The "set remotebaud" and "show remotebaud" commands are still available
1253 to provide backward compatibility with older versions of GDB.
1255 *** Changes in GDB 7.6
1257 * Target record has been renamed to record-full.
1258 Record/replay is now enabled with the "record full" command.
1259 This also affects settings that are associated with full record/replay
1260 that have been moved from "set/show record" to "set/show record full":
1262 set|show record full insn-number-max
1263 set|show record full stop-at-limit
1264 set|show record full memory-query
1266 * A new record target "record-btrace" has been added. The new target
1267 uses hardware support to record the control-flow of a process. It
1268 does not support replaying the execution, but it implements the
1269 below new commands for investigating the recorded execution log.
1270 This new recording method can be enabled using:
1274 The "record-btrace" target is only available on Intel Atom processors
1275 and requires a Linux kernel 2.6.32 or later.
1277 * Two new commands have been added for record/replay to give information
1278 about the recorded execution without having to replay the execution.
1279 The commands are only supported by "record btrace".
1281 record instruction-history prints the execution history at
1282 instruction granularity
1284 record function-call-history prints the execution history at
1285 function granularity
1287 * New native configurations
1289 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1290 FreeBSD/powerpc powerpc*-*-freebsd
1291 x86_64/Cygwin x86_64-*-cygwin*
1292 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1296 ARM AArch64 aarch64*-*-elf
1297 ARM AArch64 GNU/Linux aarch64*-*-linux
1298 Lynx 178 PowerPC powerpc-*-lynx*178
1299 x86_64/Cygwin x86_64-*-cygwin*
1300 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1302 * If the configured location of system.gdbinit file (as given by the
1303 --with-system-gdbinit option at configure time) is in the
1304 data-directory (as specified by --with-gdb-datadir at configure
1305 time) or in one of its subdirectories, then GDB will look for the
1306 system-wide init file in the directory specified by the
1307 --data-directory command-line option.
1309 * New command line options:
1311 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1312 other initialization files, unlike -nx which disables all of them.
1314 * Removed command line options
1316 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1319 * The 'ptype' and 'whatis' commands now accept an argument to control
1322 * 'info proc' now works on some core files.
1326 ** Vectors can be created with gdb.Type.vector.
1328 ** Python's atexit.register now works in GDB.
1330 ** Types can be pretty-printed via a Python API.
1332 ** Python 3 is now supported (in addition to Python 2.4 or later)
1334 ** New class gdb.Architecture exposes GDB's internal representation
1335 of architecture in the Python API.
1337 ** New method Frame.architecture returns the gdb.Architecture object
1338 corresponding to the frame's architecture.
1340 * New Python-based convenience functions:
1342 ** $_memeq(buf1, buf2, length)
1343 ** $_streq(str1, str2)
1345 ** $_regex(str, regex)
1347 * The 'cd' command now defaults to using '~' (the home directory) if not
1350 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1351 default for GCC since November 2000.
1353 * The command 'forward-search' can now be abbreviated as 'fo'.
1355 * The command 'info tracepoints' can now display 'installed on target'
1356 or 'not installed on target' for each non-pending location of tracepoint.
1358 * New configure options
1360 --enable-libmcheck/--disable-libmcheck
1361 By default, development versions are built with -lmcheck on hosts
1362 that support it, in order to help track memory corruption issues.
1363 Release versions, on the other hand, are built without -lmcheck
1364 by default. The --enable-libmcheck/--disable-libmcheck configure
1365 options allow the user to override that default.
1366 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1367 This configure option allows the user to build GDB with
1368 libbabeltrace using which GDB can read Common Trace Format data.
1370 * New commands (for set/show, see "New options" below)
1373 Catch signals. This is similar to "handle", but allows commands and
1374 conditions to be attached.
1377 List the BFDs known to GDB.
1379 python-interactive [command]
1381 Start a Python interactive prompt, or evaluate the optional command
1382 and print the result of expressions.
1385 "py" is a new alias for "python".
1387 enable type-printer [name]...
1388 disable type-printer [name]...
1389 Enable or disable type printers.
1393 ** For the Renesas Super-H architecture, the "regs" command has been removed
1394 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1399 set print type methods (on|off)
1400 show print type methods
1401 Control whether method declarations are displayed by "ptype".
1402 The default is to show them.
1404 set print type typedefs (on|off)
1405 show print type typedefs
1406 Control whether typedef definitions are displayed by "ptype".
1407 The default is to show them.
1409 set filename-display basename|relative|absolute
1410 show filename-display
1411 Control the way in which filenames is displayed.
1412 The default is "relative", which preserves previous behavior.
1414 set trace-buffer-size
1415 show trace-buffer-size
1416 Request target to change the size of trace buffer.
1418 set remote trace-buffer-size-packet auto|on|off
1419 show remote trace-buffer-size-packet
1420 Control the use of the remote protocol `QTBuffer:size' packet.
1424 Control display of debugging messages related to ARM AArch64.
1427 set debug coff-pe-read
1428 show debug coff-pe-read
1429 Control display of debugging messages related to reading of COFF/PE
1434 Control display of debugging messages related to Mach-O symbols
1437 set debug notification
1438 show debug notification
1439 Control display of debugging info for async remote notification.
1443 ** Command parameter changes are now notified using new async record
1444 "=cmd-param-changed".
1445 ** Trace frame changes caused by command "tfind" are now notified using
1446 new async record "=traceframe-changed".
1447 ** The creation, deletion and modification of trace state variables
1448 are now notified using new async records "=tsv-created",
1449 "=tsv-deleted" and "=tsv-modified".
1450 ** The start and stop of process record are now notified using new
1451 async record "=record-started" and "=record-stopped".
1452 ** Memory changes are now notified using new async record
1454 ** The data-disassemble command response will include a "fullname" field
1455 containing the absolute file name when source has been requested.
1456 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1457 command, to allow pattern filling of memory areas.
1458 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1459 library load/unload events.
1460 ** The response to breakpoint commands and breakpoint async records
1461 includes an "installed" field containing a boolean state about each
1462 non-pending tracepoint location is whether installed on target or not.
1463 ** Output of the "-trace-status" command includes a "trace-file" field
1464 containing the name of the trace file being examined. This field is
1465 optional, and only present when examining a trace file.
1466 ** The "fullname" field is now always present along with the "file" field,
1467 even if the file cannot be found by GDB.
1469 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1470 You must have the LZMA library available when configuring GDB for this
1471 feature to be enabled. For more information, see:
1472 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1474 * New remote packets
1477 Set the size of trace buffer. The remote stub reports support for this
1478 packet to gdb's qSupported query.
1481 Enable Branch Trace Store (BTS)-based branch tracing for the current
1482 thread. The remote stub reports support for this packet to gdb's
1486 Disable branch tracing for the current thread. The remote stub reports
1487 support for this packet to gdb's qSupported query.
1490 Read the traced branches for the current thread. The remote stub
1491 reports support for this packet to gdb's qSupported query.
1493 *** Changes in GDB 7.5
1495 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1496 for more x32 ABI info.
1498 * GDB now supports access to MIPS DSP registers on Linux targets.
1500 * GDB now supports debugging microMIPS binaries.
1502 * The "info os" command on GNU/Linux can now display information on
1503 several new classes of objects managed by the operating system:
1504 "info os procgroups" lists process groups
1505 "info os files" lists file descriptors
1506 "info os sockets" lists internet-domain sockets
1507 "info os shm" lists shared-memory regions
1508 "info os semaphores" lists semaphores
1509 "info os msg" lists message queues
1510 "info os modules" lists loaded kernel modules
1512 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1513 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1514 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1515 options and inspect the probe arguments using the new $_probe_arg family
1516 of convenience variables. You can obtain more information about SystemTap
1517 in <http://sourceware.org/systemtap/>.
1519 * GDB now supports reversible debugging on ARM, it allows you to
1520 debug basic ARM and THUMB instructions, and provides
1521 record/replay support.
1523 * The option "symbol-reloading" has been deleted as it is no longer used.
1527 ** GDB commands implemented in Python can now be put in command class
1530 ** The "maint set python print-stack on|off" is now deleted.
1532 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1533 apply "flag enum"-style pretty-printing to any enum.
1535 ** gdb.lookup_symbol can now work when there is no current frame.
1537 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1538 the source at which the symbol was defined.
1540 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1541 method 'value'. The former indicates whether the symbol needs a
1542 frame in order to compute its value, and the latter computes the
1545 ** A new method 'referenced_value' on gdb.Value objects which can
1546 dereference pointer as well as C++ reference values.
1548 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1549 which return the global and static blocks (as gdb.Block objects),
1550 of the underlying symbol table, respectively.
1552 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1553 object associated with a PC value.
1555 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1556 of the address range occupied by code for the current source line.
1558 * Go language support.
1559 GDB now supports debugging programs written in the Go programming
1562 * GDBserver now supports stdio connections.
1563 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1565 * The binary "gdbtui" can no longer be built or installed.
1566 Use "gdb -tui" instead.
1568 * GDB will now print "flag" enums specially. A flag enum is one where
1569 all the enumerator values have no bits in common when pairwise
1570 "and"ed. When printing a value whose type is a flag enum, GDB will
1571 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1572 (gdb) print (enum E) 3
1575 * The filename part of a linespec will now match trailing components
1576 of a source file name. For example, "break gcc/expr.c:1000" will
1577 now set a breakpoint in build/gcc/expr.c, but not
1578 build/libcpp/expr.c.
1580 * The "info proc" and "generate-core-file" commands will now also
1581 work on remote targets connected to GDBserver on Linux.
1583 * The command "info catch" has been removed. It has been disabled
1584 since December 2007.
1586 * The "catch exception" and "catch assert" commands now accept
1587 a condition at the end of the command, much like the "break"
1588 command does. For instance:
1590 (gdb) catch exception Constraint_Error if Barrier = True
1592 Previously, it was possible to add a condition to such catchpoints,
1593 but it had to be done as a second step, after the catchpoint had been
1594 created, using the "condition" command.
1596 * The "info static-tracepoint-marker" command will now also work on
1597 native Linux targets with in-process agent.
1599 * GDB can now set breakpoints on inlined functions.
1601 * The .gdb_index section has been updated to include symbols for
1602 inlined functions. GDB will ignore older .gdb_index sections by
1603 default, which could cause symbol files to be loaded more slowly
1604 until their .gdb_index sections can be recreated. The new command
1605 "set use-deprecated-index-sections on" will cause GDB to use any older
1606 .gdb_index sections it finds. This will restore performance, but the
1607 ability to set breakpoints on inlined functions will be lost in symbol
1608 files with older .gdb_index sections.
1610 The .gdb_index section has also been updated to record more information
1611 about each symbol. This speeds up the "info variables", "info functions"
1612 and "info types" commands when used with programs having the .gdb_index
1613 section, as well as speeding up debugging with shared libraries using
1614 the .gdb_index section.
1616 * Ada support for GDB/MI Variable Objects has been added.
1618 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1623 ** New command -info-os is the MI equivalent of "info os".
1625 ** Output logs ("set logging" and related) now include MI output.
1629 ** "set use-deprecated-index-sections on|off"
1630 "show use-deprecated-index-sections on|off"
1631 Controls the use of deprecated .gdb_index sections.
1633 ** "catch load" and "catch unload" can be used to stop when a shared
1634 library is loaded or unloaded, respectively.
1636 ** "enable count" can be used to auto-disable a breakpoint after
1639 ** "info vtbl" can be used to show the virtual method tables for
1640 C++ and Java objects.
1642 ** "explore" and its sub commands "explore value" and "explore type"
1643 can be used to recursively explore values and types of
1644 expressions. These commands are available only if GDB is
1645 configured with '--with-python'.
1647 ** "info auto-load" shows status of all kinds of auto-loaded files,
1648 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1649 sequences of commands files, "info auto-load python-scripts"
1650 shows status of auto-loading Python script files,
1651 "info auto-load local-gdbinit" shows status of loading init file
1652 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1653 status of inferior specific thread debugging shared library loading.
1655 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1656 and "show auto-load-scripts" commands have been deprecated, use their
1657 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1658 and "show auto-load python-scripts" counterparts instead.
1660 ** "dprintf location,format,args..." creates a dynamic printf, which
1661 is basically a breakpoint that does a printf and immediately
1662 resumes your program's execution, so it is like a printf that you
1663 can insert dynamically at runtime instead of at compiletime.
1665 ** "set print symbol"
1667 Controls whether GDB attempts to display the symbol, if any,
1668 corresponding to addresses it prints. This defaults to "on", but
1669 you can set it to "off" to restore GDB's previous behavior.
1671 * Deprecated commands
1673 ** For the Renesas Super-H architecture, the "regs" command has been
1674 deprecated, and "info all-registers" should be used instead.
1678 Renesas RL78 rl78-*-elf
1679 HP OpenVMS ia64 ia64-hp-openvms*
1681 * GDBserver supports evaluation of breakpoint conditions. When
1682 support is advertised by GDBserver, GDB may be told to send the
1683 breakpoint conditions in bytecode form to GDBserver. GDBserver
1684 will only report the breakpoint trigger to GDB when its condition
1689 set mips compression
1690 show mips compression
1691 Select the compressed ISA encoding used in functions that have no symbol
1692 information available. The encoding can be set to either of:
1695 and is updated automatically from ELF file flags if available.
1697 set breakpoint condition-evaluation
1698 show breakpoint condition-evaluation
1699 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1700 GDBserver ("target"). Default option "auto" chooses the most efficient
1702 This option can improve debugger efficiency depending on the speed of the
1706 Disable auto-loading globally.
1709 Show auto-loading setting of all kinds of auto-loaded files.
1711 set auto-load gdb-scripts on|off
1712 show auto-load gdb-scripts
1713 Control auto-loading of GDB canned sequences of commands files.
1715 set auto-load python-scripts on|off
1716 show auto-load python-scripts
1717 Control auto-loading of Python script files.
1719 set auto-load local-gdbinit on|off
1720 show auto-load local-gdbinit
1721 Control loading of init file (.gdbinit) from current directory.
1723 set auto-load libthread-db on|off
1724 show auto-load libthread-db
1725 Control auto-loading of inferior specific thread debugging shared library.
1727 set auto-load scripts-directory <dir1>[:<dir2>...]
1728 show auto-load scripts-directory
1729 Set a list of directories from which to load auto-loaded scripts.
1730 Automatically loaded Python scripts and GDB scripts are located in one
1731 of the directories listed by this option.
1732 The delimiter (':' above) may differ according to the host platform.
1734 set auto-load safe-path <dir1>[:<dir2>...]
1735 show auto-load safe-path
1736 Set a list of directories from which it is safe to auto-load files.
1737 The delimiter (':' above) may differ according to the host platform.
1739 set debug auto-load on|off
1740 show debug auto-load
1741 Control display of debugging info for auto-loading the files above.
1743 set dprintf-style gdb|call|agent
1745 Control the way in which a dynamic printf is performed; "gdb"
1746 requests a GDB printf command, while "call" causes dprintf to call a
1747 function in the inferior. "agent" requests that the target agent
1748 (such as GDBserver) do the printing.
1750 set dprintf-function <expr>
1751 show dprintf-function
1752 set dprintf-channel <expr>
1753 show dprintf-channel
1754 Set the function and optional first argument to the call when using
1755 the "call" style of dynamic printf.
1757 set disconnected-dprintf on|off
1758 show disconnected-dprintf
1759 Control whether agent-style dynamic printfs continue to be in effect
1760 after GDB disconnects.
1762 * New configure options
1764 --with-auto-load-dir
1765 Configure default value for the 'set auto-load scripts-directory'
1766 setting above. It defaults to '$debugdir:$datadir/auto-load',
1767 $debugdir representing global debugging info directories (available
1768 via 'show debug-file-directory') and $datadir representing GDB's data
1769 directory (available via 'show data-directory').
1771 --with-auto-load-safe-path
1772 Configure default value for the 'set auto-load safe-path' setting
1773 above. It defaults to the --with-auto-load-dir setting.
1775 --without-auto-load-safe-path
1776 Set 'set auto-load safe-path' to '/', effectively disabling this
1779 * New remote packets
1781 z0/z1 conditional breakpoints extension
1783 The z0/z1 breakpoint insertion packets have been extended to carry
1784 a list of conditional expressions over to the remote stub depending on the
1785 condition evaluation mode. The use of this extension can be controlled
1786 via the "set remote conditional-breakpoints-packet" command.
1790 Specify the signals which the remote stub may pass to the debugged
1791 program without GDB involvement.
1793 * New command line options
1795 --init-command=FILE, -ix Like --command, -x but execute it
1796 before loading inferior.
1797 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1798 execute it before loading inferior.
1800 *** Changes in GDB 7.4
1802 * GDB now handles ambiguous linespecs more consistently; the existing
1803 FILE:LINE support has been expanded to other types of linespecs. A
1804 breakpoint will now be set on all matching locations in all
1805 inferiors, and locations will be added or removed according to
1808 * GDB now allows you to skip uninteresting functions and files when
1809 stepping with the "skip function" and "skip file" commands.
1811 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1812 and "show remote hardware-watchpoint-length-limit". These allows to
1813 set or show the maximum length limit (in bytes) of a remote
1814 target hardware watchpoint.
1816 This allows e.g. to use "unlimited" hardware watchpoints with the
1817 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1818 watchpoints are slower than real hardware watchpoints but are
1819 significantly faster than gdb software watchpoints.
1823 ** The register_pretty_printer function in module gdb.printing now takes
1824 an optional `replace' argument. If True, the new printer replaces any
1827 ** The "maint set python print-stack on|off" command has been
1828 deprecated and will be deleted in GDB 7.5.
1829 A new command: "set python print-stack none|full|message" has
1830 replaced it. Additionally, the default for "print-stack" is
1831 now "message", which just prints the error message without
1834 ** A prompt substitution hook (prompt_hook) is now available to the
1837 ** A new Python module, gdb.prompt has been added to the GDB Python
1838 modules library. This module provides functionality for
1839 escape sequences in prompts (used by set/show
1840 extended-prompt). These escape sequences are replaced by their
1841 corresponding value.
1843 ** Python commands and convenience-functions located in
1844 'data-directory'/python/gdb/command and
1845 'data-directory'/python/gdb/function are now automatically loaded
1848 ** Blocks now provide four new attributes. global_block and
1849 static_block will return the global and static blocks
1850 respectively. is_static and is_global are boolean attributes
1851 that indicate if the block is one of those two types.
1853 ** Symbols now provide the "type" attribute, the type of the symbol.
1855 ** The "gdb.breakpoint" function has been deprecated in favor of
1858 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1859 of a function. This class is based on the "finish" command
1860 available in the CLI.
1862 ** Type objects for struct and union types now allow access to
1863 the fields using standard Python dictionary (mapping) methods.
1864 For example, "some_type['myfield']" now works, as does
1865 "some_type.items()".
1867 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1870 ** A new function, "deep_items" has been added to the gdb.types
1871 module in the GDB Python modules library. This function returns
1872 an iterator over the fields of a struct or union type. Unlike
1873 the standard Python "iteritems" method, it will recursively traverse
1874 any anonymous fields.
1878 ** "*stopped" events can report several new "reason"s, such as
1881 ** Breakpoint changes are now notified using new async records, like
1882 "=breakpoint-modified".
1884 ** New command -ada-task-info.
1886 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1887 $sdir specifies the default system locations of shared libraries.
1888 $pdir specifies the directory where the libpthread used by the application
1891 GDB no longer looks in $sdir and $pdir after it has searched the directories
1892 mentioned in libthread-db-search-path. If you want to search those
1893 directories, they must be specified in libthread-db-search-path.
1894 The default value of libthread-db-search-path on GNU/Linux and Solaris
1895 systems is now "$sdir:$pdir".
1897 $pdir is not supported by gdbserver, it is currently ignored.
1898 $sdir is supported by gdbserver.
1900 * New configure option --with-iconv-bin.
1901 When using the internationalization support like the one in the GNU C
1902 library, GDB will invoke the "iconv" program to get a list of supported
1903 character sets. If this program lives in a non-standard location, one can
1904 use this option to specify where to find it.
1906 * When natively debugging programs on PowerPC BookE processors running
1907 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1908 watchpoints, which specify a mask in addition to an address to watch.
1909 The mask specifies that some bits of an address (the bits which are
1910 reset in the mask) should be ignored when matching the address accessed
1911 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1912 section in the user manual for more details.
1914 * The new option --once causes GDBserver to stop listening for connections once
1915 the first connection is made. The listening port used by GDBserver will
1916 become available after that.
1918 * New commands "info macros" and "alias" have been added.
1920 * New function parameters suffix @entry specifies value of function parameter
1921 at the time the function got called. Entry values are available only since
1927 "!" is now an alias of the "shell" command.
1928 Note that no space is needed between "!" and SHELL COMMAND.
1932 watch EXPRESSION mask MASK_VALUE
1933 The watch command now supports the mask argument which allows creation
1934 of masked watchpoints, if the current architecture supports this feature.
1936 info auto-load-scripts [REGEXP]
1937 This command was formerly named "maintenance print section-scripts".
1938 It is now generally useful and is no longer a maintenance-only command.
1940 info macro [-all] [--] MACRO
1941 The info macro command has new options `-all' and `--'. The first for
1942 printing all definitions of a macro. The second for explicitly specifying
1943 the end of arguments and the beginning of the macro name in case the macro
1944 name starts with a hyphen.
1946 collect[/s] EXPRESSIONS
1947 The tracepoint collect command now takes an optional modifier "/s"
1948 that directs it to dereference pointer-to-character types and
1949 collect the bytes of memory up to a zero byte. The behavior is
1950 similar to what you see when you use the regular print command on a
1951 string. An optional integer following the "/s" sets a bound on the
1952 number of bytes that will be collected.
1955 The trace start command now interprets any supplied arguments as a
1956 note to be recorded with the trace run, with an effect similar to
1957 setting the variable trace-notes.
1960 The trace stop command now interprets any arguments as a note to be
1961 mentioned along with the tstatus report that the trace was stopped
1962 with a command. The effect is similar to setting the variable
1965 * Tracepoints can now be enabled and disabled at any time after a trace
1966 experiment has been started using the standard "enable" and "disable"
1967 commands. It is now possible to start a trace experiment with no enabled
1968 tracepoints; GDB will display a warning, but will allow the experiment to
1969 begin, assuming that tracepoints will be enabled as needed while the trace
1972 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1973 locations with 4-byte instructions, when they were previously
1974 limited to locations with instructions of 5 bytes or longer.
1978 set debug dwarf2-read
1979 show debug dwarf2-read
1980 Turns on or off display of debugging messages related to reading
1981 DWARF debug info. The default is off.
1983 set debug symtab-create
1984 show debug symtab-create
1985 Turns on or off display of debugging messages related to symbol table
1986 creation. The default is off.
1989 show extended-prompt
1990 Set the GDB prompt, and allow escape sequences to be inserted to
1991 display miscellaneous information (see 'help set extended-prompt'
1992 for the list of sequences). This prompt (and any information
1993 accessed through the escape sequences) is updated every time the
1994 prompt is displayed.
1996 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1997 show print entry-values
1998 Set printing of frame argument values at function entry. In some cases
1999 GDB can determine the value of function argument which was passed by the
2000 function caller, even if the value was modified inside the called function.
2002 set debug entry-values
2003 show debug entry-values
2004 Control display of debugging info for determining frame argument values at
2005 function entry and virtual tail call frames.
2007 set basenames-may-differ
2008 show basenames-may-differ
2009 Set whether a source file may have multiple base names.
2010 (A "base name" is the name of a file with the directory part removed.
2011 Example: The base name of "/home/user/hello.c" is "hello.c".)
2012 If set, GDB will canonicalize file names (e.g., expand symlinks)
2013 before comparing them. Canonicalization is an expensive operation,
2014 but it allows the same file be known by more than one base name.
2015 If not set (the default), all source files are assumed to have just
2016 one base name, and gdb will do file name comparisons more efficiently.
2022 Set a user name and notes for the current and any future trace runs.
2023 This is useful for long-running and/or disconnected traces, to
2024 inform others (or yourself) as to who is running the trace, supply
2025 contact information, or otherwise explain what is going on.
2027 set trace-stop-notes
2028 show trace-stop-notes
2029 Set a note attached to the trace run, that is displayed when the
2030 trace has been stopped by a tstop command. This is useful for
2031 instance as an explanation, if you are stopping a trace run that was
2032 started by someone else.
2034 * New remote packets
2038 Dynamically enable a tracepoint in a started trace experiment.
2042 Dynamically disable a tracepoint in a started trace experiment.
2046 Set the user and notes of the trace run.
2050 Query the current status of a tracepoint.
2054 Query the minimum length of instruction at which a fast tracepoint may
2057 * Dcache size (number of lines) and line-size are now runtime-configurable
2058 via "set dcache line" and "set dcache line-size" commands.
2062 Texas Instruments TMS320C6x tic6x-*-*
2066 Renesas RL78 rl78-*-elf
2068 *** Changes in GDB 7.3.1
2070 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2072 *** Changes in GDB 7.3
2074 * GDB has a new command: "thread find [REGEXP]".
2075 It finds the thread id whose name, target id, or thread extra info
2076 matches the given regular expression.
2078 * The "catch syscall" command now works on mips*-linux* targets.
2080 * The -data-disassemble MI command now supports modes 2 and 3 for
2081 dumping the instruction opcodes.
2083 * New command line options
2085 -data-directory DIR Specify DIR as the "data-directory".
2086 This is mostly for testing purposes.
2088 * The "maint set python auto-load on|off" command has been renamed to
2089 "set auto-load-scripts on|off".
2091 * GDB has a new command: "set directories".
2092 It is like the "dir" command except that it replaces the
2093 source path list instead of augmenting it.
2095 * GDB now understands thread names.
2097 On GNU/Linux, "info threads" will display the thread name as set by
2098 prctl or pthread_setname_np.
2100 There is also a new command, "thread name", which can be used to
2101 assign a name internally for GDB to display.
2104 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2105 has been integrated into GDB.
2109 ** The function gdb.Write now accepts an optional keyword 'stream'.
2110 This keyword, when provided, will direct the output to either
2111 stdout, stderr, or GDB's logging output.
2113 ** Parameters can now be be sub-classed in Python, and in particular
2114 you may implement the get_set_doc and get_show_doc functions.
2115 This improves how Parameter set/show documentation is processed
2116 and allows for more dynamic content.
2118 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2119 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2120 have an is_valid method.
2122 ** Breakpoints can now be sub-classed in Python, and in particular
2123 you may implement a 'stop' function that is executed each time
2124 the inferior reaches that breakpoint.
2126 ** New function gdb.lookup_global_symbol looks up a global symbol.
2128 ** GDB values in Python are now callable if the value represents a
2129 function. For example, if 'some_value' represents a function that
2130 takes two integer parameters and returns a value, you can call
2131 that function like so:
2133 result = some_value (10,20)
2135 ** Module gdb.types has been added.
2136 It contains a collection of utilities for working with gdb.Types objects:
2137 get_basic_type, has_field, make_enum_dict.
2139 ** Module gdb.printing has been added.
2140 It contains utilities for writing and registering pretty-printers.
2141 New classes: PrettyPrinter, SubPrettyPrinter,
2142 RegexpCollectionPrettyPrinter.
2143 New function: register_pretty_printer.
2145 ** New commands "info pretty-printers", "enable pretty-printer" and
2146 "disable pretty-printer" have been added.
2148 ** gdb.parameter("directories") is now available.
2150 ** New function gdb.newest_frame returns the newest frame in the
2153 ** The gdb.InferiorThread class has a new "name" attribute. This
2154 holds the thread's name.
2156 ** Python Support for Inferior events.
2157 Python scripts can add observers to be notified of events
2158 occurring in the process being debugged.
2159 The following events are currently supported:
2160 - gdb.events.cont Continue event.
2161 - gdb.events.exited Inferior exited event.
2162 - gdb.events.stop Signal received, and Breakpoint hit events.
2166 ** GDB now puts template parameters in scope when debugging in an
2167 instantiation. For example, if you have:
2169 template<int X> int func (void) { return X; }
2171 then if you step into func<5>, "print X" will show "5". This
2172 feature requires proper debuginfo support from the compiler; it
2173 was added to GCC 4.5.
2175 ** The motion commands "next", "finish", "until", and "advance" now
2176 work better when exceptions are thrown. In particular, GDB will
2177 no longer lose control of the inferior; instead, the GDB will
2178 stop the inferior at the point at which the exception is caught.
2179 This functionality requires a change in the exception handling
2180 code that was introduced in GCC 4.5.
2182 * GDB now follows GCC's rules on accessing volatile objects when
2183 reading or writing target state during expression evaluation.
2184 One notable difference to prior behavior is that "print x = 0"
2185 no longer generates a read of x; the value of the assignment is
2186 now always taken directly from the value being assigned.
2188 * GDB now has some support for using labels in the program's source in
2189 linespecs. For instance, you can use "advance label" to continue
2190 execution to a label.
2192 * GDB now has support for reading and writing a new .gdb_index
2193 section. This section holds a fast index of DWARF debugging
2194 information and can be used to greatly speed up GDB startup and
2195 operation. See the documentation for `save gdb-index' for details.
2197 * The "watch" command now accepts an optional "-location" argument.
2198 When used, this causes GDB to watch the memory referred to by the
2199 expression. Such a watchpoint is never deleted due to it going out
2202 * GDB now supports thread debugging of core dumps on GNU/Linux.
2204 GDB now activates thread debugging using the libthread_db library
2205 when debugging GNU/Linux core dumps, similarly to when debugging
2206 live processes. As a result, when debugging a core dump file, GDB
2207 is now able to display pthread_t ids of threads. For example, "info
2208 threads" shows the same output as when debugging the process when it
2209 was live. In earlier releases, you'd see something like this:
2212 * 1 LWP 6780 main () at main.c:10
2214 While now you see this:
2217 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2219 It is also now possible to inspect TLS variables when debugging core
2222 When debugging a core dump generated on a machine other than the one
2223 used to run GDB, you may need to point GDB at the correct
2224 libthread_db library with the "set libthread-db-search-path"
2225 command. See the user manual for more details on this command.
2227 * When natively debugging programs on PowerPC BookE processors running
2228 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2229 which stop execution of the inferior whenever it executes an instruction
2230 at any address within the specified range. See the "PowerPC Embedded"
2231 section in the user manual for more details.
2233 * New features in the GDB remote stub, GDBserver
2235 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2236 and i686 LynxOS (version 5.x).
2238 ** GDBserver is now supported on Blackfin Linux.
2240 * New native configurations
2242 ia64 HP-UX ia64-*-hpux*
2246 Analog Devices, Inc. Blackfin Processor bfin-*
2248 * Ada task switching is now supported on sparc-elf targets when
2249 debugging a program using the Ravenscar Profile. For more information,
2250 see the "Tasking Support when using the Ravenscar Profile" section
2251 in the GDB user manual.
2253 * Guile support was removed.
2255 * New features in the GNU simulator
2257 ** The --map-info flag lists all known core mappings.
2259 ** CFI flashes may be simulated via the "cfi" device.
2261 *** Changes in GDB 7.2
2263 * Shared library support for remote targets by default
2265 When GDB is configured for a generic, non-OS specific target, like
2266 for example, --target=arm-eabi or one of the many *-*-elf targets,
2267 GDB now queries remote stubs for loaded shared libraries using the
2268 `qXfer:libraries:read' packet. Previously, shared library support
2269 was always disabled for such configurations.
2273 ** Argument Dependent Lookup (ADL)
2275 In C++ ADL lookup directs function search to the namespaces of its
2276 arguments even if the namespace has not been imported.
2286 Here the compiler will search for `foo' in the namespace of 'b'
2287 and find A::foo. GDB now supports this. This construct is commonly
2288 used in the Standard Template Library for operators.
2290 ** Improved User Defined Operator Support
2292 In addition to member operators, GDB now supports lookup of operators
2293 defined in a namespace and imported with a `using' directive, operators
2294 defined in the global scope, operators imported implicitly from an
2295 anonymous namespace, and the ADL operators mentioned in the previous
2297 GDB now also supports proper overload resolution for all the previously
2298 mentioned flavors of operators.
2300 ** static const class members
2302 Printing of static const class members that are initialized in the
2303 class definition has been fixed.
2305 * Windows Thread Information Block access.
2307 On Windows targets, GDB now supports displaying the Windows Thread
2308 Information Block (TIB) structure. This structure is visible either
2309 by using the new command `info w32 thread-information-block' or, by
2310 dereferencing the new convenience variable named `$_tlb', a
2311 thread-specific pointer to the TIB. This feature is also supported
2312 when remote debugging using GDBserver.
2314 * Static tracepoints
2316 Static tracepoints are calls in the user program into a tracing
2317 library. One such library is a port of the LTTng kernel tracer to
2318 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2319 When debugging with GDBserver, GDB now supports combining the GDB
2320 tracepoint machinery with such libraries. For example: the user can
2321 use GDB to probe a static tracepoint marker (a call from the user
2322 program into the tracing library) with the new "strace" command (see
2323 "New commands" below). This creates a "static tracepoint" in the
2324 breakpoint list, that can be manipulated with the same feature set
2325 as fast and regular tracepoints. E.g., collect registers, local and
2326 global variables, collect trace state variables, and define
2327 tracepoint conditions. In addition, the user can collect extra
2328 static tracepoint marker specific data, by collecting the new
2329 $_sdata internal variable. When analyzing the trace buffer, you can
2330 inspect $_sdata like any other variable available to GDB. For more
2331 information, see the "Tracepoints" chapter in GDB user manual. New
2332 remote packets have been defined to support static tracepoints, see
2333 the "New remote packets" section below.
2335 * Better reconstruction of tracepoints after disconnected tracing
2337 GDB will attempt to download the original source form of tracepoint
2338 definitions when starting a trace run, and then will upload these
2339 upon reconnection to the target, resulting in a more accurate
2340 reconstruction of the tracepoints that are in use on the target.
2344 You can now exercise direct control over the ways that GDB can
2345 affect your program. For instance, you can disallow the setting of
2346 breakpoints, so that the program can run continuously (assuming
2347 non-stop mode). In addition, the "observer" variable is available
2348 to switch all of the different controls; in observer mode, GDB
2349 cannot affect the target's behavior at all, which is useful for
2350 tasks like diagnosing live systems in the field.
2352 * The new convenience variable $_thread holds the number of the
2355 * New remote packets
2359 Return the address of the Windows Thread Information Block of a given thread.
2363 In response to several of the tracepoint packets, the target may now
2364 also respond with a number of intermediate `qRelocInsn' request
2365 packets before the final result packet, to have GDB handle
2366 relocating an instruction to execute at a different address. This
2367 is particularly useful for stubs that support fast tracepoints. GDB
2368 reports support for this feature in the qSupported packet.
2372 List static tracepoint markers in the target program.
2376 List static tracepoint markers at a given address in the target
2379 qXfer:statictrace:read
2381 Read the static trace data collected (by a `collect $_sdata'
2382 tracepoint action). The remote stub reports support for this packet
2383 to gdb's qSupported query.
2387 Send the current settings of GDB's permission flags.
2391 Send part of the source (textual) form of a tracepoint definition,
2392 which includes location, conditional, and action list.
2394 * The source command now accepts a -s option to force searching for the
2395 script in the source search path even if the script name specifies
2398 * New features in the GDB remote stub, GDBserver
2400 - GDBserver now support tracepoints (including fast tracepoints, and
2401 static tracepoints). The feature is currently supported by the
2402 i386-linux and amd64-linux builds. See the "Tracepoints support
2403 in gdbserver" section in the manual for more information.
2405 GDBserver JIT compiles the tracepoint's conditional agent
2406 expression bytecode into native code whenever possible for low
2407 overhead dynamic tracepoints conditionals. For such tracepoints,
2408 an expression that examines program state is evaluated when the
2409 tracepoint is reached, in order to determine whether to capture
2410 trace data. If the condition is simple and false, processing the
2411 tracepoint finishes very quickly and no data is gathered.
2413 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2414 for static tracepoints support.
2416 - GDBserver now supports x86_64 Windows 64-bit debugging.
2418 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2419 it understands register description.
2421 * The --batch flag now disables pagination and queries.
2423 * X86 general purpose registers
2425 GDB now supports reading/writing byte, word and double-word x86
2426 general purpose registers directly. This means you can use, say,
2427 $ah or $ax to refer, respectively, to the byte register AH and
2428 16-bit word register AX that are actually portions of the 32-bit
2429 register EAX or 64-bit register RAX.
2431 * The `commands' command now accepts a range of breakpoints to modify.
2432 A plain `commands' following a command that creates multiple
2433 breakpoints affects all the breakpoints set by that command. This
2434 applies to breakpoints set by `rbreak', and also applies when a
2435 single `break' command creates multiple breakpoints (e.g.,
2436 breakpoints on overloaded c++ functions).
2438 * The `rbreak' command now accepts a filename specification as part of
2439 its argument, limiting the functions selected by the regex to those
2440 in the specified file.
2442 * Support for remote debugging Windows and SymbianOS shared libraries
2443 from Unix hosts has been improved. Non Windows GDB builds now can
2444 understand target reported file names that follow MS-DOS based file
2445 system semantics, such as file names that include drive letters and
2446 use the backslash character as directory separator. This makes it
2447 possible to transparently use the "set sysroot" and "set
2448 solib-search-path" on Unix hosts to point as host copies of the
2449 target's shared libraries. See the new command "set
2450 target-file-system-kind" described below, and the "Commands to
2451 specify files" section in the user manual for more information.
2455 eval template, expressions...
2456 Convert the values of one or more expressions under the control
2457 of the string template to a command line, and call it.
2459 set target-file-system-kind unix|dos-based|auto
2460 show target-file-system-kind
2461 Set or show the assumed file system kind for target reported file
2464 save breakpoints <filename>
2465 Save all current breakpoint definitions to a file suitable for use
2466 in a later debugging session. To read the saved breakpoint
2467 definitions, use the `source' command.
2469 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2472 info static-tracepoint-markers
2473 Display information about static tracepoint markers in the target.
2475 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2476 Define a static tracepoint by probing a marker at the given
2477 function, line, address, or marker ID.
2481 Enable and disable observer mode.
2483 set may-write-registers on|off
2484 set may-write-memory on|off
2485 set may-insert-breakpoints on|off
2486 set may-insert-tracepoints on|off
2487 set may-insert-fast-tracepoints on|off
2488 set may-interrupt on|off
2489 Set individual permissions for GDB effects on the target. Note that
2490 some of these settings can have undesirable or surprising
2491 consequences, particularly when changed in the middle of a session.
2492 For instance, disabling the writing of memory can prevent
2493 breakpoints from being inserted, cause single-stepping to fail, or
2494 even crash your program, if you disable after breakpoints have been
2495 inserted. However, GDB should not crash.
2497 set record memory-query on|off
2498 show record memory-query
2499 Control whether to stop the inferior if memory changes caused
2500 by an instruction cannot be recorded.
2505 The disassemble command now supports "start,+length" form of two arguments.
2509 ** GDB now provides a new directory location, called the python directory,
2510 where Python scripts written for GDB can be installed. The location
2511 of that directory is <data-directory>/python, where <data-directory>
2512 is the GDB data directory. For more details, see section `Scripting
2513 GDB using Python' in the manual.
2515 ** The GDB Python API now has access to breakpoints, symbols, symbol
2516 tables, program spaces, inferiors, threads and frame's code blocks.
2517 Additionally, GDB Parameters can now be created from the API, and
2518 manipulated via set/show in the CLI.
2520 ** New functions gdb.target_charset, gdb.target_wide_charset,
2521 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2523 ** New exception gdb.GdbError.
2525 ** Pretty-printers are now also looked up in the current program space.
2527 ** Pretty-printers can now be individually enabled and disabled.
2529 ** GDB now looks for names of Python scripts to auto-load in a
2530 special section named `.debug_gdb_scripts', in addition to looking
2531 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2533 * Tracepoint actions were unified with breakpoint commands. In particular,
2534 there are no longer differences in "info break" output for breakpoints and
2535 tracepoints and the "commands" command can be used for both tracepoints and
2536 regular breakpoints.
2540 ARM Symbian arm*-*-symbianelf*
2542 * D language support.
2543 GDB now supports debugging programs written in the D programming
2546 * GDB now supports the extended ptrace interface for PowerPC which is
2547 available since Linux kernel version 2.6.34. This automatically enables
2548 any hardware breakpoints and additional hardware watchpoints available in
2549 the processor. The old ptrace interface exposes just one hardware
2550 watchpoint and no hardware breakpoints.
2552 * GDB is now able to use the Data Value Compare (DVC) register available on
2553 embedded PowerPC processors to implement in hardware simple watchpoint
2554 conditions of the form:
2556 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2558 This works in native GDB running on Linux kernels with the extended ptrace
2559 interface mentioned above.
2561 *** Changes in GDB 7.1
2565 ** Namespace Support
2567 GDB now supports importing of namespaces in C++. This enables the
2568 user to inspect variables from imported namespaces. Support for
2569 namepace aliasing has also been added. So, if a namespace is
2570 aliased in the current scope (e.g. namepace C=A; ) the user can
2571 print variables using the alias (e.g. (gdb) print C::x).
2575 All known bugs relating to the printing of virtual base class were
2576 fixed. It is now possible to call overloaded static methods using a
2581 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2582 and reinterpret_cast<> are now handled by the C++ expression parser.
2586 Xilinx MicroBlaze microblaze-*-*
2591 Xilinx MicroBlaze microblaze
2594 * Multi-program debugging.
2596 GDB now has support for multi-program (a.k.a. multi-executable or
2597 multi-exec) debugging. This allows for debugging multiple inferiors
2598 simultaneously each running a different program under the same GDB
2599 session. See "Debugging Multiple Inferiors and Programs" in the
2600 manual for more information. This implied some user visible changes
2601 in the multi-inferior support. For example, "info inferiors" now
2602 lists inferiors that are not running yet or that have exited
2603 already. See also "New commands" and "New options" below.
2605 * New tracing features
2607 GDB's tracepoint facility now includes several new features:
2609 ** Trace state variables
2611 GDB tracepoints now include support for trace state variables, which
2612 are variables managed by the target agent during a tracing
2613 experiment. They are useful for tracepoints that trigger each
2614 other, so for instance one tracepoint can count hits in a variable,
2615 and then a second tracepoint has a condition that is true when the
2616 count reaches a particular value. Trace state variables share the
2617 $-syntax of GDB convenience variables, and can appear in both
2618 tracepoint actions and condition expressions. Use the "tvariable"
2619 command to create, and "info tvariables" to view; see "Trace State
2620 Variables" in the manual for more detail.
2624 GDB now includes an option for defining fast tracepoints, which
2625 targets may implement more efficiently, such as by installing a jump
2626 into the target agent rather than a trap instruction. The resulting
2627 speedup can be by two orders of magnitude or more, although the
2628 tradeoff is that some program locations on some target architectures
2629 might not allow fast tracepoint installation, for instance if the
2630 instruction to be replaced is shorter than the jump. To request a
2631 fast tracepoint, use the "ftrace" command, with syntax identical to
2632 the regular trace command.
2634 ** Disconnected tracing
2636 It is now possible to detach GDB from the target while it is running
2637 a trace experiment, then reconnect later to see how the experiment
2638 is going. In addition, a new variable disconnected-tracing lets you
2639 tell the target agent whether to continue running a trace if the
2640 connection is lost unexpectedly.
2644 GDB now has the ability to save the trace buffer into a file, and
2645 then use that file as a target, similarly to you can do with
2646 corefiles. You can select trace frames, print data that was
2647 collected in them, and use tstatus to display the state of the
2648 tracing run at the moment that it was saved. To create a trace
2649 file, use "tsave <filename>", and to use it, do "target tfile
2652 ** Circular trace buffer
2654 You can ask the target agent to handle the trace buffer as a
2655 circular buffer, discarding the oldest trace frames to make room for
2656 newer ones, by setting circular-trace-buffer to on. This feature may
2657 not be available for all target agents.
2662 The disassemble command, when invoked with two arguments, now requires
2663 the arguments to be comma-separated.
2666 The info variables command now displays variable definitions. Files
2667 which only declare a variable are not shown.
2670 The source command is now capable of sourcing Python scripts.
2671 This feature is dependent on the debugger being build with Python
2674 Related to this enhancement is also the introduction of a new command
2675 "set script-extension" (see below).
2677 * New commands (for set/show, see "New options" below)
2679 record save [<FILENAME>]
2680 Save a file (in core file format) containing the process record
2681 execution log for replay debugging at a later time.
2683 record restore <FILENAME>
2684 Restore the process record execution log that was saved at an
2685 earlier time, for replay debugging.
2687 add-inferior [-copies <N>] [-exec <FILENAME>]
2690 clone-inferior [-copies <N>] [ID]
2691 Make a new inferior ready to execute the same program another
2692 inferior has loaded.
2697 maint info program-spaces
2698 List the program spaces loaded into GDB.
2700 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2701 show remote interrupt-sequence
2702 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2703 as the sequence to the remote target in order to interrupt the execution.
2704 Ctrl-C is a default. Some system prefers BREAK which is high level of
2705 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2706 Magic SysRq g. It is BREAK signal and character 'g'.
2708 set remote interrupt-on-connect [on | off]
2709 show remote interrupt-on-connect
2710 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2711 remote target when gdb connects to it. This is needed when you debug
2714 set remotebreak [on | off]
2716 Deprecated. Use "set/show remote interrupt-sequence" instead.
2718 tvariable $NAME [ = EXP ]
2719 Create or modify a trace state variable.
2722 List trace state variables and their values.
2724 delete tvariable $NAME ...
2725 Delete one or more trace state variables.
2728 Evaluate the given expressions without collecting anything into the
2729 trace buffer. (Valid in tracepoint actions only.)
2731 ftrace FN / FILE:LINE / *ADDR
2732 Define a fast tracepoint at the given function, line, or address.
2734 * New expression syntax
2736 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2737 GDB now parses 0b101010 identically with 42.
2741 set follow-exec-mode new|same
2742 show follow-exec-mode
2743 Control whether GDB reuses the same inferior across an exec call or
2744 creates a new one. This is useful to be able to restart the old
2745 executable after the inferior having done an exec call.
2747 set default-collect EXPR, ...
2748 show default-collect
2749 Define a list of expressions to be collected at each tracepoint.
2750 This is a useful way to ensure essential items are not overlooked,
2751 such as registers or a critical global variable.
2753 set disconnected-tracing
2754 show disconnected-tracing
2755 If set to 1, the target is instructed to continue tracing if it
2756 loses its connection to GDB. If 0, the target is to stop tracing
2759 set circular-trace-buffer
2760 show circular-trace-buffer
2761 If set to on, the target is instructed to use a circular trace buffer
2762 and discard the oldest trace frames instead of stopping the trace due
2763 to a full trace buffer. If set to off, the trace stops when the buffer
2764 fills up. Some targets may not support this.
2766 set script-extension off|soft|strict
2767 show script-extension
2768 If set to "off", the debugger does not perform any script language
2769 recognition, and all sourced files are assumed to be GDB scripts.
2770 If set to "soft" (the default), files are sourced according to
2771 filename extension, falling back to GDB scripts if the first
2773 If set to "strict", files are sourced according to filename extension.
2775 set ada trust-PAD-over-XVS on|off
2776 show ada trust-PAD-over-XVS
2777 If off, activate a workaround against a bug in the debugging information
2778 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2779 the GCC sources for more information about the GNAT encoding and
2780 PAD types in particular). It is always safe to set this option to
2781 off, but this introduces a slight performance penalty. The default
2784 * Python API Improvements
2786 ** GDB provides the new class gdb.LazyString. This is useful in
2787 some pretty-printing cases. The new method gdb.Value.lazy_string
2788 provides a simple way to create objects of this type.
2790 ** The fields returned by gdb.Type.fields now have an
2791 `is_base_class' attribute.
2793 ** The new method gdb.Type.range returns the range of an array type.
2795 ** The new method gdb.parse_and_eval can be used to parse and
2796 evaluate an expression.
2798 * New remote packets
2801 Define a trace state variable.
2804 Get the current value of a trace state variable.
2807 Set desired tracing behavior upon disconnection.
2810 Set the trace buffer to be linear or circular.
2813 Get data about the tracepoints currently in use.
2817 Process record now works correctly with hardware watchpoints.
2819 Multiple bug fixes have been made to the mips-irix port, making it
2820 much more reliable. In particular:
2821 - Debugging threaded applications is now possible again. Previously,
2822 GDB would hang while starting the program, or while waiting for
2823 the program to stop at a breakpoint.
2824 - Attaching to a running process no longer hangs.
2825 - An error occurring while loading a core file has been fixed.
2826 - Changing the value of the PC register now works again. This fixes
2827 problems observed when using the "jump" command, or when calling
2828 a function from GDB, or even when assigning a new value to $pc.
2829 - With the "finish" and "return" commands, the return value for functions
2830 returning a small array is now correctly printed.
2831 - It is now possible to break on shared library code which gets executed
2832 during a shared library init phase (code executed while executing
2833 their .init section). Previously, the breakpoint would have no effect.
2834 - GDB is now able to backtrace through the signal handler for
2835 non-threaded programs.
2837 PIE (Position Independent Executable) programs debugging is now supported.
2838 This includes debugging execution of PIC (Position Independent Code) shared
2839 libraries although for that, it should be possible to run such libraries as an
2842 *** Changes in GDB 7.0
2844 * GDB now has an interface for JIT compilation. Applications that
2845 dynamically generate code can create symbol files in memory and register
2846 them with GDB. For users, the feature should work transparently, and
2847 for JIT developers, the interface is documented in the GDB manual in the
2848 "JIT Compilation Interface" chapter.
2850 * Tracepoints may now be conditional. The syntax is as for
2851 breakpoints; either an "if" clause appended to the "trace" command,
2852 or the "condition" command is available. GDB sends the condition to
2853 the target for evaluation using the same bytecode format as is used
2854 for tracepoint actions.
2856 * The disassemble command now supports: an optional /r modifier, print the
2857 raw instructions in hex as well as in symbolic form, and an optional /m
2858 modifier to print mixed source+assembly.
2860 * Process record and replay
2862 In a architecture environment that supports ``process record and
2863 replay'', ``process record and replay'' target can record a log of
2864 the process execution, and replay it with both forward and reverse
2867 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2868 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2869 set execution-direction {forward|reverse}, for targets that support
2872 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2873 feature is available with a native GDB running on kernel version
2876 * GDB now has support for multi-byte and wide character sets on the
2877 target. Strings whose character type is wchar_t, char16_t, or
2878 char32_t are now correctly printed. GDB supports wide- and unicode-
2879 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2880 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2881 `printf'. This feature requires iconv to work properly; if your
2882 system does not have a working iconv, GDB can use GNU libiconv. See
2883 the installation instructions for more information.
2885 * GDB now supports automatic retrieval of shared library files from
2886 remote targets. To use this feature, specify a system root that begins
2887 with the `remote:' prefix, either via the `set sysroot' command or via
2888 the `--with-sysroot' configure-time option.
2890 * "info sharedlibrary" now takes an optional regex of libraries to show,
2891 and it now reports if a shared library has no debugging information.
2893 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2894 now complete on file names.
2896 * When completing in expressions, gdb will attempt to limit
2897 completions to allowable structure or union fields, where appropriate.
2898 For instance, consider:
2900 # struct example { int f1; double f2; };
2901 # struct example variable;
2904 If the user types TAB at the end of this command line, the available
2905 completions will be "f1" and "f2".
2907 * Inlined functions are now supported. They show up in backtraces, and
2908 the "step", "next", and "finish" commands handle them automatically.
2910 * GDB now supports the token-splicing (##) and stringification (#)
2911 operators when expanding macros. It also supports variable-arity
2914 * GDB now supports inspecting extra signal information, exported by
2915 the new $_siginfo convenience variable. The feature is currently
2916 implemented on linux ARM, i386 and amd64.
2918 * GDB can now display the VFP floating point registers and NEON vector
2919 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2920 can provide these registers (requires Linux 2.6.30 or later). Remote
2921 and simulator targets may also provide them.
2923 * New remote packets
2926 Search memory for a sequence of bytes.
2929 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2930 operation over reliable transport links. Use of this packet is
2931 controlled by the `set remote noack-packet' command.
2934 Kill the process with the specified process ID. Use this in preference
2935 to `k' when multiprocess protocol extensions are supported.
2938 Obtains additional operating system information
2942 Read or write additional signal information.
2944 * Removed remote protocol undocumented extension
2946 An undocumented extension to the remote protocol's `S' stop reply
2947 packet that permited the stub to pass a process id was removed.
2948 Remote servers should use the `T' stop reply packet instead.
2950 * GDB now supports multiple function calling conventions according to the
2951 DWARF-2 DW_AT_calling_convention function attribute.
2953 * The SH target utilizes the aforementioned change to distinguish between gcc
2954 and Renesas calling convention. It also adds the new CLI commands
2955 `set/show sh calling-convention'.
2957 * GDB can now read compressed debug sections, as produced by GNU gold
2958 with the --compress-debug-sections=zlib flag.
2960 * 64-bit core files are now supported on AIX.
2962 * Thread switching is now supported on Tru64.
2964 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2965 which will be allocated using malloc later in program execution.
2967 * The qXfer:libraries:read remote procotol packet now allows passing a
2968 list of section offsets.
2970 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2971 conditions handling signals delivered during attach or thread creation
2972 have also been fixed.
2974 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2975 From the user's standpoint, all unqualified instances of True and False
2976 are treated as the standard definitions, regardless of context.
2978 * GDB now parses C++ symbol and type names more flexibly. For
2981 template<typename T> class C { };
2984 GDB will now correctly handle all of:
2986 ptype C<char const *>
2987 ptype C<char const*>
2988 ptype C<const char *>
2989 ptype C<const char*>
2991 * New features in the GDB remote stub, gdbserver
2993 - The "--wrapper" command-line argument tells gdbserver to use a
2994 wrapper program to launch programs for debugging.
2996 - On PowerPC and S/390 targets, it is now possible to use a single
2997 gdbserver executable to debug both 32-bit and 64-bit programs.
2998 (This requires gdbserver itself to be built as a 64-bit executable.)
3000 - gdbserver uses the new noack protocol mode for TCP connections to
3001 reduce communications latency, if also supported and enabled in GDB.
3003 - Support for the sparc64-linux-gnu target is now included in
3006 - The amd64-linux build of gdbserver now supports debugging both
3007 32-bit and 64-bit programs.
3009 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3010 now support hardware watchpoints, and will use them automatically
3015 GDB now has support for scripting using Python. Whether this is
3016 available is determined at configure time.
3018 New GDB commands can now be written in Python.
3020 * Ada tasking support
3022 Ada tasks can now be inspected in GDB. The following commands have
3026 Print the list of Ada tasks.
3028 Print detailed information about task number N.
3030 Print the task number of the current task.
3032 Switch the context of debugging to task number N.
3034 * Support for user-defined prefixed commands. The "define" command can
3035 add new commands to existing prefixes, e.g. "target".
3037 * Multi-inferior, multi-process debugging.
3039 GDB now has generalized support for multi-inferior debugging. See
3040 "Debugging Multiple Inferiors" in the manual for more information.
3041 Although availability still depends on target support, the command
3042 set is more uniform now. The GNU/Linux specific multi-forks support
3043 has been migrated to this new framework. This implied some user
3044 visible changes; see "New commands" and also "Removed commands"
3047 * Target descriptions can now describe the target OS ABI. See the
3048 "Target Description Format" section in the user manual for more
3051 * Target descriptions can now describe "compatible" architectures
3052 to indicate that the target can execute applications for a different
3053 architecture in addition to those for the main target architecture.
3054 See the "Target Description Format" section in the user manual for
3057 * Multi-architecture debugging.
3059 GDB now includes general supports for debugging applications on
3060 hybrid systems that use more than one single processor architecture
3061 at the same time. Each such hybrid architecture still requires
3062 specific support to be added. The only hybrid architecture supported
3063 in this version of GDB is the Cell Broadband Engine.
3065 * GDB now supports integrated debugging of Cell/B.E. applications that
3066 use both the PPU and SPU architectures. To enable support for hybrid
3067 Cell/B.E. debugging, you need to configure GDB to support both the
3068 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3069 --enable-targets configure option.
3071 * Non-stop mode debugging.
3073 For some targets, GDB now supports an optional mode of operation in
3074 which you can examine stopped threads while other threads continue
3075 to execute freely. This is referred to as non-stop mode, with the
3076 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3077 section in the user manual for more information.
3079 To be able to support remote non-stop debugging, a remote stub needs
3080 to implement the non-stop mode remote protocol extensions, as
3081 described in the "Remote Non-Stop" section of the user manual. The
3082 GDB remote stub, gdbserver, has been adjusted to support these
3083 extensions on linux targets.
3085 * New commands (for set/show, see "New options" below)
3087 catch syscall [NAME(S) | NUMBER(S)]
3088 Catch system calls. Arguments, which should be names of system
3089 calls or their numbers, mean catch only those syscalls. Without
3090 arguments, every syscall will be caught. When the inferior issues
3091 any of the specified syscalls, GDB will stop and announce the system
3092 call, both when it is called and when its call returns. This
3093 feature is currently available with a native GDB running on the
3094 Linux Kernel, under the following architectures: x86, x86_64,
3095 PowerPC and PowerPC64.
3097 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3099 Search memory for a sequence of bytes.
3101 maint set python print-stack
3102 maint show python print-stack
3103 Show a stack trace when an error is encountered in a Python script.
3106 Invoke CODE by passing it to the Python interpreter.
3111 These allow macros to be defined, undefined, and listed
3115 Show operating system information about processes.
3118 List the inferiors currently under GDB's control.
3121 Switch focus to inferior number NUM.
3124 Detach from inferior number NUM.
3127 Kill inferior number NUM.
3131 set spu stop-on-load
3132 show spu stop-on-load
3133 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3135 set spu auto-flush-cache
3136 show spu auto-flush-cache
3137 Control whether to automatically flush the software-managed cache
3138 during Cell/B.E. debugging.
3140 set sh calling-convention
3141 show sh calling-convention
3142 Control the calling convention used when calling SH target functions.
3145 show debug timestamp
3146 Control display of timestamps with GDB debugging output.
3148 set disassemble-next-line
3149 show disassemble-next-line
3150 Control display of disassembled source lines or instructions when
3153 set remote noack-packet
3154 show remote noack-packet
3155 Set/show the use of remote protocol QStartNoAckMode packet. See above
3156 under "New remote packets."
3158 set remote query-attached-packet
3159 show remote query-attached-packet
3160 Control use of remote protocol `qAttached' (query-attached) packet.
3162 set remote read-siginfo-object
3163 show remote read-siginfo-object
3164 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3167 set remote write-siginfo-object
3168 show remote write-siginfo-object
3169 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3172 set remote reverse-continue
3173 show remote reverse-continue
3174 Control use of remote protocol 'bc' (reverse-continue) packet.
3176 set remote reverse-step
3177 show remote reverse-step
3178 Control use of remote protocol 'bs' (reverse-step) packet.
3180 set displaced-stepping
3181 show displaced-stepping
3182 Control displaced stepping mode. Displaced stepping is a way to
3183 single-step over breakpoints without removing them from the debuggee.
3184 Also known as "out-of-line single-stepping".
3187 show debug displaced
3188 Control display of debugging info for displaced stepping.
3190 maint set internal-error
3191 maint show internal-error
3192 Control what GDB does when an internal error is detected.
3194 maint set internal-warning
3195 maint show internal-warning
3196 Control what GDB does when an internal warning is detected.
3201 Use a wrapper program to launch programs for debugging.
3203 set multiple-symbols (all|ask|cancel)
3204 show multiple-symbols
3205 The value of this variable can be changed to adjust the debugger behavior
3206 when an expression or a breakpoint location contains an ambiguous symbol
3207 name (an overloaded function name, for instance).
3209 set breakpoint always-inserted
3210 show breakpoint always-inserted
3211 Keep breakpoints always inserted in the target, as opposed to inserting
3212 them when resuming the target, and removing them when the target stops.
3213 This option can improve debugger performance on slow remote targets.
3215 set arm fallback-mode (arm|thumb|auto)
3216 show arm fallback-mode
3217 set arm force-mode (arm|thumb|auto)
3219 These commands control how ARM GDB determines whether instructions
3220 are ARM or Thumb. The default for both settings is auto, which uses
3221 the current CPSR value for instructions without symbols; previous
3222 versions of GDB behaved as if "set arm fallback-mode arm".
3224 set disable-randomization
3225 show disable-randomization
3226 Standalone programs run with the virtual address space randomization enabled
3227 by default on some platforms. This option keeps the addresses stable across
3228 multiple debugging sessions.
3232 Control whether other threads are stopped or not when some thread hits
3237 Requests that asynchronous execution is enabled in the target, if available.
3238 In this case, it's possible to resume target in the background, and interact
3239 with GDB while the target is running. "show target-async" displays the
3240 current state of asynchronous execution of the target.
3242 set target-wide-charset
3243 show target-wide-charset
3244 The target-wide-charset is the name of the character set that GDB
3245 uses when printing characters whose type is wchar_t.
3247 set tcp auto-retry (on|off)
3249 set tcp connect-timeout
3250 show tcp connect-timeout
3251 These commands allow GDB to retry failed TCP connections to a remote stub
3252 with a specified timeout period; this is useful if the stub is launched
3253 in parallel with GDB but may not be ready to accept connections immediately.
3255 set libthread-db-search-path
3256 show libthread-db-search-path
3257 Control list of directories which GDB will search for appropriate
3260 set schedule-multiple (on|off)
3261 show schedule-multiple
3262 Allow GDB to resume all threads of all processes or only threads of
3263 the current process.
3267 Use more aggressive caching for accesses to the stack. This improves
3268 performance of remote debugging (particularly backtraces) without
3269 affecting correctness.
3271 set interactive-mode (on|off|auto)
3272 show interactive-mode
3273 Control whether GDB runs in interactive mode (on) or not (off).
3274 When in interactive mode, GDB waits for the user to answer all
3275 queries. Otherwise, GDB does not wait and assumes the default
3276 answer. When set to auto (the default), GDB determines which
3277 mode to use based on the stdin settings.
3282 For program forks, this is replaced by the new more generic `info
3283 inferiors' command. To list checkpoints, you can still use the
3284 `info checkpoints' command, which was an alias for the `info forks'
3288 Replaced by the new `inferior' command. To switch between
3289 checkpoints, you can still use the `restart' command, which was an
3290 alias for the `fork' command.
3293 This is removed, since some targets don't have a notion of
3294 processes. To switch between processes, you can still use the
3295 `inferior' command using GDB's own inferior number.
3298 For program forks, this is replaced by the new more generic `kill
3299 inferior' command. To delete a checkpoint, you can still use the
3300 `delete checkpoint' command, which was an alias for the `delete
3304 For program forks, this is replaced by the new more generic `detach
3305 inferior' command. To detach a checkpoint, you can still use the
3306 `detach checkpoint' command, which was an alias for the `detach
3309 * New native configurations
3311 x86/x86_64 Darwin i[34567]86-*-darwin*
3313 x86_64 MinGW x86_64-*-mingw*
3317 Lattice Mico32 lm32-*
3318 x86 DICOS i[34567]86-*-dicos*
3319 x86_64 DICOS x86_64-*-dicos*
3322 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3323 (mingw32ce) debugging.
3329 These commands were actually not implemented on any target.
3331 *** Changes in GDB 6.8
3333 * New native configurations
3335 NetBSD/hppa hppa*-*netbsd*
3336 Xtensa GNU/Linux xtensa*-*-linux*
3340 NetBSD/hppa hppa*-*-netbsd*
3341 Xtensa GNU/Lunux xtensa*-*-linux*
3343 * Change in command line behavior -- corefiles vs. process ids.
3345 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3346 attaching to process NUMBER fails, GDB no longer attempts to open a
3347 core file named NUMBER. Attaching to a program using the -c option
3348 is no longer supported. Instead, use the '-p' or '--pid' options.
3350 * GDB can now be built as a native debugger for debugging Windows x86
3351 (mingw32) Portable Executable (PE) programs.
3353 * Pending breakpoints no longer change their number when their address
3356 * GDB now supports breakpoints with multiple locations,
3357 including breakpoints on C++ constructors, inside C++ templates,
3358 and in inlined functions.
3360 * GDB's ability to debug optimized code has been improved. GDB more
3361 accurately identifies function bodies and lexical blocks that occupy
3362 more than one contiguous range of addresses.
3364 * Target descriptions can now describe registers for PowerPC.
3366 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3367 registers on PowerPC targets.
3369 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3370 targets even when the libthread_db library is not available.
3372 * The GDB remote stub, gdbserver, now supports the new file transfer
3373 commands (remote put, remote get, and remote delete).
3375 * The GDB remote stub, gdbserver, now supports run and attach in
3376 extended-remote mode.
3378 * hppa*64*-*-hpux11* target broken
3379 The debugger is unable to start a program and fails with the following
3380 error: "Error trying to get information about dynamic linker".
3381 The gdb-6.7 release is also affected.
3383 * GDB now supports the --enable-targets= configure option to allow
3384 building a single GDB executable that supports multiple remote
3385 target architectures.
3387 * GDB now supports debugging C and C++ programs which use the
3388 Decimal Floating Point extension. In addition, the PowerPC target
3389 now has a set of pseudo-registers to inspect decimal float values
3390 stored in two consecutive float registers.
3392 * The -break-insert MI command can optionally create pending
3395 * Improved support for debugging Ada
3396 Many improvements to the Ada language support have been made. These
3398 - Better support for Ada2005 interface types
3399 - Improved handling of arrays and slices in general
3400 - Better support for Taft-amendment types
3401 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3403 - Improved command completion in Ada
3406 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3411 set print frame-arguments (all|scalars|none)
3412 show print frame-arguments
3413 The value of this variable can be changed to control which argument
3414 values should be printed by the debugger when displaying a frame.
3419 Transfer files to and from a remote target, and delete remote files.
3426 Transfer files to and from a remote target, and delete remote files.
3428 * New remote packets
3435 Open, close, read, write, and delete files on the remote system.
3438 Attach to an existing process on the remote system, in extended-remote
3442 Run a new process on the remote system, in extended-remote mode.
3444 *** Changes in GDB 6.7
3446 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3447 bfd, libiberty and opcodes, as revealed by static analysis donated by
3448 Coverity, Inc. (http://scan.coverity.com).
3450 * When looking up multiply-defined global symbols, GDB will now prefer the
3451 symbol definition in the current shared library if it was built using the
3452 -Bsymbolic linker option.
3454 * When the Text User Interface (TUI) is not configured, GDB will now
3455 recognize the -tui command-line option and print a message that the TUI
3458 * The GDB remote stub, gdbserver, now has lower overhead for high
3459 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3461 * GDB for MIPS targets now autodetects whether a remote target provides
3462 32-bit or 64-bit register values.
3464 * Support for C++ member pointers has been improved.
3466 * GDB now understands XML target descriptions, which specify the
3467 target's overall architecture. GDB can read a description from
3468 a local file or over the remote serial protocol.
3470 * Vectors of single-byte data use a new integer type which is not
3471 automatically displayed as character or string data.
3473 * The /s format now works with the print command. It displays
3474 arrays of single-byte integers and pointers to single-byte integers
3477 * Target descriptions can now describe target-specific registers,
3478 for architectures which have implemented the support (currently
3479 only ARM, M68K, and MIPS).
3481 * GDB and the GDB remote stub, gdbserver, now support the XScale
3484 * The GDB remote stub, gdbserver, has been updated to support
3485 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3486 has been rewritten to use the standard GDB remote protocol.
3488 * GDB can now step into C++ functions which are called through thunks.
3490 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3492 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3493 layout. It also supports a TextSeg= and DataSeg= response when only
3494 segment base addresses (rather than offsets) are available.
3496 * The /i format now outputs any trailing branch delay slot instructions
3497 immediately following the last instruction within the count specified.
3499 * The GDB remote protocol "T" stop reply packet now supports a
3500 "library" response. Combined with the new "qXfer:libraries:read"
3501 packet, this response allows GDB to debug shared libraries on targets
3502 where the operating system manages the list of loaded libraries (e.g.
3503 Windows and SymbianOS).
3505 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3506 (DLLs) on Windows and Windows CE targets.
3508 * GDB now supports a faster verification that a .debug file matches its binary
3509 according to its build-id signature, if the signature is present.
3515 Enable or disable hardware flow control (RTS/CTS) on the serial port
3516 when debugging using remote targets.
3518 set mem inaccessible-by-default
3519 show mem inaccessible-by-default
3520 If the target supplies a memory map, for instance via the remote
3521 protocol's "qXfer:memory-map:read" packet, setting this variable
3522 prevents GDB from accessing memory outside the memory map. This
3523 is useful for targets with memory mapped registers or which react
3524 badly to accesses of unmapped address space.
3526 set breakpoint auto-hw
3527 show breakpoint auto-hw
3528 If the target supplies a memory map, for instance via the remote
3529 protocol's "qXfer:memory-map:read" packet, setting this variable
3530 lets GDB use hardware breakpoints automatically for memory regions
3531 where it can not use software breakpoints. This covers both the
3532 "break" command and internal breakpoints used for other commands
3533 including "next" and "finish".
3536 catch exception unhandled
3537 Stop the program execution when Ada exceptions are raised.
3540 Stop the program execution when an Ada assertion failed.
3544 Set an alternate system root for target files. This is a more
3545 general version of "set solib-absolute-prefix", which is now
3546 an alias to "set sysroot".
3549 Provide extended SPU facility status information. This set of
3550 commands is available only when debugging the Cell/B.E. SPU
3553 * New native configurations
3555 OpenBSD/sh sh*-*openbsd*
3558 unset tdesc filename
3560 Use the specified local file as an XML target description, and do
3561 not query the target for its built-in description.
3565 OpenBSD/sh sh*-*-openbsd*
3566 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3567 Toshiba Media Processor mep-elf
3569 * New remote packets
3572 Ignore the specified signals; pass them directly to the debugged program
3573 without stopping other threads or reporting them to GDB.
3575 qXfer:features:read:
3576 Read an XML target description from the target, which describes its
3581 Read or write contents of an spufs file on the target system. These
3582 packets are available only on the Cell/B.E. SPU architecture.
3584 qXfer:libraries:read:
3585 Report the loaded shared libraries. Combined with new "T" packet
3586 response, this packet allows GDB to debug shared libraries on
3587 targets where the operating system manages the list of loaded
3588 libraries (e.g. Windows and SymbianOS).
3592 Support for these obsolete configurations has been removed.
3600 i[34567]86-*-lynxos*
3601 i[34567]86-*-netware*
3602 i[34567]86-*-sco3.2v5*
3603 i[34567]86-*-sco3.2v4*
3605 i[34567]86-*-sysv4.2*
3608 i[34567]86-*-unixware2*
3609 i[34567]86-*-unixware*
3618 * Other removed features
3625 Various m68k-only ROM monitors.
3632 Various Renesas ROM monitors and debugging interfaces for SH and
3637 Support for a Macraigor serial interface to on-chip debugging.
3638 GDB does not directly support the newer parallel or USB
3643 A debug information format. The predecessor to DWARF 2 and
3644 DWARF 3, which are still supported.
3646 Support for the HP aCC compiler on HP-UX/PA-RISC
3648 SOM-encapsulated symbolic debugging information, automatic
3649 invocation of pxdb, and the aCC custom C++ ABI. This does not
3650 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3651 with aCC can still be debugged on an assembly level.
3653 MIPS ".pdr" sections
3655 A MIPS-specific format used to describe stack frame layout
3656 in debugging information.
3660 GDB could work with an older version of Guile to debug
3661 the interpreter and Scheme programs running in it.
3663 set mips stack-arg-size
3664 set mips saved-gpreg-size
3666 Use "set mips abi" to control parameter passing for MIPS.
3668 *** Changes in GDB 6.6
3673 Cell Broadband Engine SPU spu-elf
3675 * GDB can now be configured as a cross-debugger targeting native Windows
3676 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3677 running on a Windows system over TCP/IP to debug Windows programs.
3679 * The GDB remote stub, gdbserver, has been updated to support Windows and
3680 Cygwin debugging. Both single-threaded and multi-threaded programs are
3683 * The "set trust-readonly-sections" command works again. This command was
3684 broken in GDB 6.3, 6.4, and 6.5.
3686 * The "load" command now supports writing to flash memory, if the remote
3687 stub provides the required support.
3689 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3690 longer requires symbolic debug information (e.g. DWARF-2).
3695 unset substitute-path
3696 show substitute-path
3697 Manage a list of substitution rules that GDB uses to rewrite the name
3698 of the directories where the sources are located. This can be useful
3699 for instance when the sources were moved to a different location
3700 between compilation and debugging.
3704 Print each CLI command as it is executed. Each command is prefixed with
3705 a number of `+' symbols representing the nesting depth.
3706 The source command now has a `-v' option to enable the same feature.
3710 The ARM Demon monitor support (RDP protocol, "target rdp").
3712 Kernel Object Display, an embedded debugging feature which only worked with
3713 an obsolete version of Cisco IOS.
3715 The 'set download-write-size' and 'show download-write-size' commands.
3717 * New remote packets
3720 Tell a stub about GDB client features, and request remote target features.
3721 The first feature implemented is PacketSize, which allows the target to
3722 specify the size of packets it can handle - to minimize the number of
3723 packets required and improve performance when connected to a remote
3727 Fetch an OS auxilliary vector from the remote stub. This packet is a
3728 more efficient replacement for qPart:auxv:read.
3730 qXfer:memory-map:read:
3731 Fetch a memory map from the remote stub, including information about
3732 RAM, ROM, and flash memory devices.
3737 Erase and program a flash memory device.
3739 * Removed remote packets
3742 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3743 used it, and only gdbserver implemented it.
3745 *** Changes in GDB 6.5
3749 Renesas M32C/M16C m32c-elf
3751 Morpho Technologies ms1 ms1-elf
3755 init-if-undefined Initialize a convenience variable, but
3756 only if it doesn't already have a value.
3758 The following commands are presently only implemented for native GNU/Linux:
3760 checkpoint Save a snapshot of the program state.
3762 restart <n> Return the program state to a
3763 previously saved state.
3765 info checkpoints List currently saved checkpoints.
3767 delete-checkpoint <n> Delete a previously saved checkpoint.
3769 set|show detach-on-fork Tell gdb whether to detach from a newly
3770 forked process, or to keep debugging it.
3772 info forks List forks of the user program that
3773 are available to be debugged.
3775 fork <n> Switch to debugging one of several
3776 forks of the user program that are
3777 available to be debugged.
3779 delete-fork <n> Delete a fork from the list of forks
3780 that are available to be debugged (and
3781 kill the forked process).
3783 detach-fork <n> Delete a fork from the list of forks
3784 that are available to be debugged (and
3785 allow the process to continue).
3789 Morpho Technologies ms2 ms1-elf
3791 * Improved Windows host support
3793 GDB now builds as a cross debugger hosted on i686-mingw32, including
3794 native console support, and remote communications using either
3795 network sockets or serial ports.
3797 * Improved Modula-2 language support
3799 GDB can now print most types in the Modula-2 syntax. This includes:
3800 basic types, set types, record types, enumerated types, range types,
3801 pointer types and ARRAY types. Procedure var parameters are correctly
3802 printed and hexadecimal addresses and character constants are also
3803 written in the Modula-2 syntax. Best results can be obtained by using
3804 GNU Modula-2 together with the -gdwarf-2 command line option.
3808 The ARM rdi-share module.
3810 The Netware NLM debug server.
3812 *** Changes in GDB 6.4
3814 * New native configurations
3816 OpenBSD/arm arm*-*-openbsd*
3817 OpenBSD/mips64 mips64-*-openbsd*
3821 Morpho Technologies ms1 ms1-elf
3823 * New command line options
3825 --batch-silent As for --batch, but totally silent.
3826 --return-child-result The debugger will exist with the same value
3827 the child (debugged) program exited with.
3828 --eval-command COMMAND, -ex COMMAND
3829 Execute a single GDB CLI command. This may be
3830 specified multiple times and in conjunction
3831 with the --command (-x) option.
3833 * Deprecated commands removed
3835 The following commands, that were deprecated in 2000, have been
3839 set|show arm disassembly-flavor set|show arm disassembler
3840 othernames set arm disassembler
3841 set|show remotedebug set|show debug remote
3842 set|show archdebug set|show debug arch
3843 set|show eventdebug set|show debug event
3846 * New BSD user-level threads support
3848 It is now possible to debug programs using the user-level threads
3849 library on OpenBSD and FreeBSD. Currently supported (target)
3852 FreeBSD/amd64 x86_64-*-freebsd*
3853 FreeBSD/i386 i386-*-freebsd*
3854 OpenBSD/i386 i386-*-openbsd*
3856 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3857 are not yet supported.
3859 * New support for Matsushita MN10300 w/sim added
3860 (Work in progress). mn10300-elf.
3862 * REMOVED configurations and files
3864 VxWorks and the XDR protocol *-*-vxworks
3865 Motorola MCORE mcore-*-*
3866 National Semiconductor NS32000 ns32k-*-*
3868 * New "set print array-indexes" command
3870 After turning this setting "on", GDB prints the index of each element
3871 when displaying arrays. The default is "off" to preserve the previous
3874 * VAX floating point support
3876 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3878 * User-defined command support
3880 In addition to using $arg0..$arg9 for argument passing, it is now possible
3881 to use $argc to determine now many arguments have been passed. See the
3882 section on user-defined commands in the user manual for more information.
3884 *** Changes in GDB 6.3:
3886 * New command line option
3888 GDB now accepts -l followed by a number to set the timeout for remote
3891 * GDB works with GCC -feliminate-dwarf2-dups
3893 GDB now supports a more compact representation of DWARF-2 debug
3894 information using DW_FORM_ref_addr references. These are produced
3895 by GCC with the option -feliminate-dwarf2-dups and also by some
3896 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3897 to use -feliminate-dwarf2-dups.
3899 * Internationalization
3901 When supported by the host system, GDB will be built with
3902 internationalization (libintl). The task of marking up the sources is
3903 continued, we're looking forward to our first translation.
3907 Initial support for debugging programs compiled with the GNAT
3908 implementation of the Ada programming language has been integrated
3909 into GDB. In this release, support is limited to expression evaluation.
3911 * New native configurations
3913 GNU/Linux/m32r m32r-*-linux-gnu
3917 GDB's remote protocol now includes support for the 'p' packet. This
3918 packet is used to fetch individual registers from a remote inferior.
3920 * END-OF-LIFE registers[] compatibility module
3922 GDB's internal register infrastructure has been completely rewritten.
3923 The new infrastructure making possible the implementation of key new
3924 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3927 GDB 6.3 will be the last release to include the the registers[]
3928 compatibility module that allowed out-of-date configurations to
3929 continue to work. This change directly impacts the following
3939 powerpc bdm protocol
3941 Unless there is activity to revive these configurations, they will be
3942 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3944 * OBSOLETE configurations and files
3946 Configurations that have been declared obsolete in this release have
3947 been commented out. Unless there is activity to revive these
3948 configurations, the next release of GDB will have their sources
3949 permanently REMOVED.
3958 *** Changes in GDB 6.2.1:
3960 * MIPS `break main; run' gave an heuristic-fence-post warning
3962 When attempting to run even a simple program, a warning about
3963 heuristic-fence-post being hit would be reported. This problem has
3966 * MIPS IRIX 'long double' crashed GDB
3968 When examining a long double variable, GDB would get a segmentation
3969 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3970 IRIX long double values).
3974 A bug in the VAX stack code was causing problems with the "next"
3975 command. This problem has been fixed.
3977 *** Changes in GDB 6.2:
3979 * Fix for ``many threads''
3981 On GNU/Linux systems that use the NPTL threads library, a program
3982 rapidly creating and deleting threads would confuse GDB leading to the
3985 ptrace: No such process.
3986 thread_db_get_info: cannot get thread info: generic error
3988 This problem has been fixed.
3990 * "-async" and "-noasync" options removed.
3992 Support for the broken "-noasync" option has been removed (it caused
3995 * New ``start'' command.
3997 This command runs the program until the begining of the main procedure.
3999 * New BSD Kernel Data Access Library (libkvm) interface
4001 Using ``target kvm'' it is now possible to debug kernel core dumps and
4002 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4003 platforms. Currently supported (native-only) configurations are:
4005 FreeBSD/amd64 x86_64-*-freebsd*
4006 FreeBSD/i386 i?86-*-freebsd*
4007 NetBSD/i386 i?86-*-netbsd*
4008 NetBSD/m68k m68*-*-netbsd*
4009 NetBSD/sparc sparc-*-netbsd*
4010 OpenBSD/amd64 x86_64-*-openbsd*
4011 OpenBSD/i386 i?86-*-openbsd*
4012 OpenBSD/m68k m68*-openbsd*
4013 OpenBSD/sparc sparc-*-openbsd*
4015 * Signal trampoline code overhauled
4017 Many generic problems with GDB's signal handling code have been fixed.
4018 These include: backtraces through non-contiguous stacks; recognition
4019 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4020 call; backtrace through a signal trampoline; step into and out of
4021 signal handlers; and single-stepping in the signal trampoline.
4023 Please note that kernel bugs are a limiting factor here. These
4024 features have been shown to work on an s390 GNU/Linux system that
4025 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4027 * Cygwin support for DWARF 2 added.
4029 * New native configurations
4031 GNU/Linux/hppa hppa*-*-linux*
4032 OpenBSD/hppa hppa*-*-openbsd*
4033 OpenBSD/m68k m68*-*-openbsd*
4034 OpenBSD/m88k m88*-*-openbsd*
4035 OpenBSD/powerpc powerpc-*-openbsd*
4036 NetBSD/vax vax-*-netbsd*
4037 OpenBSD/vax vax-*-openbsd*
4039 * END-OF-LIFE frame compatibility module
4041 GDB's internal frame infrastructure has been completely rewritten.
4042 The new infrastructure making it possible to support key new features
4043 including DWARF 2 Call Frame Information. To aid in the task of
4044 migrating old configurations to this new infrastructure, a
4045 compatibility module, that allowed old configurations to continue to
4046 work, was also included.
4048 GDB 6.2 will be the last release to include this frame compatibility
4049 module. This change directly impacts the following configurations:
4059 Unless there is activity to revive these configurations, they will be
4060 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4062 * REMOVED configurations and files
4064 Sun 3, running SunOS 3 m68*-*-sunos3*
4065 Sun 3, running SunOS 4 m68*-*-sunos4*
4066 Sun 2, running SunOS 3 m68000-*-sunos3*
4067 Sun 2, running SunOS 4 m68000-*-sunos4*
4068 Motorola 680x0 running LynxOS m68*-*-lynxos*
4069 AT&T 3b1/Unix pc m68*-att-*
4070 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4071 decstation mips-dec-* mips-little-*
4072 riscos mips-*-riscos* mips-*-sysv*
4073 sonymips mips-sony-*
4074 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4076 *** Changes in GDB 6.1.1:
4078 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4080 The TUI (Text-mode User Interface) is now built as part of a default
4081 GDB configuration. It is enabled by either selecting the TUI with the
4082 command line option "-i=tui" or by running the separate "gdbtui"
4083 program. For more information on the TUI, see the manual "Debugging
4086 * Pending breakpoint support (also included in GDB 6.1)
4088 Support has been added to allow you to specify breakpoints in shared
4089 libraries that have not yet been loaded. If a breakpoint location
4090 cannot be found, and the "breakpoint pending" option is set to auto,
4091 GDB queries you if you wish to make the breakpoint pending on a future
4092 shared-library load. If and when GDB resolves the breakpoint symbol,
4093 the pending breakpoint is removed as one or more regular breakpoints
4096 Pending breakpoints are very useful for GCJ Java debugging.
4098 * Fixed ISO-C build problems
4100 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4101 non ISO-C code that stopped them being built using a more strict ISO-C
4102 compiler (e.g., IBM's C compiler).
4104 * Fixed build problem on IRIX 5
4106 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4107 wasn't able to compile compile on an IRIX 5 system.
4109 * Added execute permission to gdb/gdbserver/configure
4111 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4112 permission. This bug would cause configure to fail on a number of
4113 systems (Solaris, IRIX). Ref: server/519.
4115 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4117 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4118 has been updated to use constant array sizes.
4120 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4122 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4123 its generated DWARF Call Frame Info. This encoding was causing GDB to
4124 panic, that panic has been fixed. Ref: gdb/1628.
4126 * Fixed a problem when examining parameters in shared library code.
4128 When examining parameters in optimized shared library code generated
4129 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4130 not available''. GDB now correctly displays the variable's value.
4132 *** Changes in GDB 6.1:
4134 * Removed --with-mmalloc
4136 Support for the mmalloc memory manager has been removed, as it
4137 conflicted with the internal gdb byte cache.
4139 * Changes in AMD64 configurations
4141 The AMD64 target now includes the %cs and %ss registers. As a result
4142 the AMD64 remote protocol has changed; this affects the floating-point
4143 and SSE registers. If you rely on those registers for your debugging,
4144 you should upgrade gdbserver on the remote side.
4146 * Revised SPARC target
4148 The SPARC target has been completely revised, incorporating the
4149 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4150 support for LynxOS and SunOS 4 has been dropped. Calling functions
4151 from within GDB on operating systems with a non-executable stack
4152 (Solaris, OpenBSD) now works.
4156 GDB has a new C++ demangler which does a better job on the mangled
4157 names generated by current versions of g++. It also runs faster, so
4158 with this and other changes gdb should now start faster on large C++
4161 * DWARF 2 Location Expressions
4163 GDB support for location expressions has been extended to support function
4164 arguments and frame bases. Older versions of GDB could crash when they
4167 * C++ nested types and namespaces
4169 GDB's support for nested types and namespaces in C++ has been
4170 improved, especially if you use the DWARF 2 debugging format. (This
4171 is the default for recent versions of GCC on most platforms.)
4172 Specifically, if you have a class "Inner" defined within a class or
4173 namespace "Outer", then GDB realizes that the class's name is
4174 "Outer::Inner", not simply "Inner". This should greatly reduce the
4175 frequency of complaints about not finding RTTI symbols. In addition,
4176 if you are stopped at inside of a function defined within a namespace,
4177 GDB modifies its name lookup accordingly.
4179 * New native configurations
4181 NetBSD/amd64 x86_64-*-netbsd*
4182 OpenBSD/amd64 x86_64-*-openbsd*
4183 OpenBSD/alpha alpha*-*-openbsd*
4184 OpenBSD/sparc sparc-*-openbsd*
4185 OpenBSD/sparc64 sparc64-*-openbsd*
4187 * New debugging protocols
4189 M32R with SDI protocol m32r-*-elf*
4191 * "set prompt-escape-char" command deleted.
4193 The command "set prompt-escape-char" has been deleted. This command,
4194 and its very obscure effet on GDB's prompt, was never documented,
4195 tested, nor mentioned in the NEWS file.
4197 * OBSOLETE configurations and files
4199 Configurations that have been declared obsolete in this release have
4200 been commented out. Unless there is activity to revive these
4201 configurations, the next release of GDB will have their sources
4202 permanently REMOVED.
4204 Sun 3, running SunOS 3 m68*-*-sunos3*
4205 Sun 3, running SunOS 4 m68*-*-sunos4*
4206 Sun 2, running SunOS 3 m68000-*-sunos3*
4207 Sun 2, running SunOS 4 m68000-*-sunos4*
4208 Motorola 680x0 running LynxOS m68*-*-lynxos*
4209 AT&T 3b1/Unix pc m68*-att-*
4210 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4211 decstation mips-dec-* mips-little-*
4212 riscos mips-*-riscos* mips-*-sysv*
4213 sonymips mips-sony-*
4214 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4216 * REMOVED configurations and files
4218 SGI Irix-4.x mips-sgi-irix4 or iris4
4219 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4220 Z8000 simulator z8k-zilog-none or z8ksim
4221 Matsushita MN10200 w/simulator mn10200-*-*
4222 H8/500 simulator h8500-hitachi-hms or h8500hms
4223 HP/PA running BSD hppa*-*-bsd*
4224 HP/PA running OSF/1 hppa*-*-osf*
4225 HP/PA Pro target hppa*-*-pro*
4226 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4227 386BSD i[3456]86-*-bsd*
4228 Sequent family i[3456]86-sequent-sysv4*
4229 i[3456]86-sequent-sysv*
4230 i[3456]86-sequent-bsd*
4231 SPARC running LynxOS sparc-*-lynxos*
4232 SPARC running SunOS 4 sparc-*-sunos4*
4233 Tsqware Sparclet sparclet-*-*
4234 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4236 *** Changes in GDB 6.0:
4240 Support for debugging the Objective-C programming language has been
4241 integrated into GDB.
4243 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4245 DWARF 2's Call Frame Information makes available compiler generated
4246 information that more exactly describes the program's run-time stack.
4247 By using this information, GDB is able to provide more robust stack
4250 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4251 have been updated to use a new backtrace mechanism which includes
4252 DWARF 2 CFI support.
4256 GDB's remote protocol has been extended to include support for hosted
4257 file I/O (where the remote target uses GDB's file system). See GDB's
4258 remote protocol documentation for details.
4260 * All targets using the new architecture framework.
4262 All of GDB's targets have been updated to use the new internal
4263 architecture framework. The way is now open for future GDB releases
4264 to include cross-architecture native debugging support (i386 on amd64,
4267 * GNU/Linux's Thread Local Storage (TLS)
4269 GDB now includes support for for the GNU/Linux implementation of
4270 per-thread variables.
4272 * GNU/Linux's Native POSIX Thread Library (NPTL)
4274 GDB's thread code has been updated to work with either the new
4275 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4277 * Separate debug info.
4279 GDB, in conjunction with BINUTILS, now supports a mechanism for
4280 automatically loading debug information from a separate file. Instead
4281 of shipping full debug and non-debug versions of system libraries,
4282 system integrators can now instead ship just the stripped libraries
4283 and optional debug files.
4285 * DWARF 2 Location Expressions
4287 DWARF 2 Location Expressions allow the compiler to more completely
4288 describe the location of variables (even in optimized code) to the
4291 GDB now includes preliminary support for location expressions (support
4292 for DW_OP_piece is still missing).
4296 A number of long standing bugs that caused GDB to die while starting a
4297 Java application have been fixed. GDB's Java support is now
4298 considered "useable".
4300 * GNU/Linux support for fork, vfork, and exec.
4302 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4303 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4306 * GDB supports logging output to a file
4308 There are two new commands, "set logging" and "show logging", which can be
4309 used to capture GDB's output to a file.
4311 * The meaning of "detach" has changed for gdbserver
4313 The "detach" command will now resume the application, as documented. To
4314 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4317 * d10v, m68hc11 `regs' command deprecated
4319 The `info registers' command has been updated so that it displays the
4320 registers using a format identical to the old `regs' command.
4324 A new command, "maint set profile on/off", has been added. This command can
4325 be used to enable or disable profiling while running GDB, to profile a
4326 session or a set of commands. In addition there is a new configure switch,
4327 "--enable-profiling", which will cause GDB to be compiled with profiling
4328 data, for more informative profiling results.
4330 * Default MI syntax changed to "mi2".
4332 The default MI (machine interface) syntax, enabled by the command line
4333 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4334 "mi1", can be enabled by specifying the option "-i=mi1".
4336 Support for the original "mi0" syntax (included in GDB 5.0) has been
4339 Fix for gdb/192: removed extraneous space when displaying frame level.
4340 Fix for gdb/672: update changelist is now output in mi list format.
4341 Fix for gdb/702: a -var-assign that updates the value now shows up
4342 in a subsequent -var-update.
4344 * New native configurations.
4346 FreeBSD/amd64 x86_64-*-freebsd*
4348 * Multi-arched targets.
4350 HP/PA HPUX11 hppa*-*-hpux*
4351 Renesas M32R/D w/simulator m32r-*-elf*
4353 * OBSOLETE configurations and files
4355 Configurations that have been declared obsolete in this release have
4356 been commented out. Unless there is activity to revive these
4357 configurations, the next release of GDB will have their sources
4358 permanently REMOVED.
4360 Z8000 simulator z8k-zilog-none or z8ksim
4361 Matsushita MN10200 w/simulator mn10200-*-*
4362 H8/500 simulator h8500-hitachi-hms or h8500hms
4363 HP/PA running BSD hppa*-*-bsd*
4364 HP/PA running OSF/1 hppa*-*-osf*
4365 HP/PA Pro target hppa*-*-pro*
4366 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4367 Sequent family i[3456]86-sequent-sysv4*
4368 i[3456]86-sequent-sysv*
4369 i[3456]86-sequent-bsd*
4370 Tsqware Sparclet sparclet-*-*
4371 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4373 * REMOVED configurations and files
4376 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4377 IBM AIX PS/2 i[3456]86-*-aix
4378 i386 running Mach 3.0 i[3456]86-*-mach3*
4379 i386 running Mach i[3456]86-*-mach*
4380 i386 running OSF/1 i[3456]86-*osf1mk*
4381 HP/Apollo 68k Family m68*-apollo*-sysv*,
4383 m68*-hp-bsd*, m68*-hp-hpux*
4384 Argonaut Risc Chip (ARC) arc-*-*
4385 Mitsubishi D30V d30v-*-*
4386 Fujitsu FR30 fr30-*-elf*
4387 OS/9000 i[34]86-*-os9k
4388 I960 with MON960 i960-*-coff
4390 * MIPS $fp behavior changed
4392 The convenience variable $fp, for the MIPS, now consistently returns
4393 the address of the current frame's base. Previously, depending on the
4394 context, $fp could refer to either $sp or the current frame's base
4395 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4396 The GNU Source-Level Debugger''.
4398 *** Changes in GDB 5.3:
4400 * GNU/Linux shared library multi-threaded performance improved.
4402 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4403 `/proc', in preference to `ptrace' for memory reads. This may result
4404 in an improvement in the start-up time of multi-threaded, shared
4405 library applications when run under GDB. One GDB user writes: ``loads
4406 shared libs like mad''.
4408 * ``gdbserver'' now supports multi-threaded applications on some targets
4410 Support for debugging multi-threaded applications which use
4411 the GNU/Linux LinuxThreads package has been added for
4412 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4413 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4415 * GDB now supports C/C++ preprocessor macros.
4417 GDB now expands preprocessor macro invocations in C/C++ expressions,
4418 and provides various commands for showing macro definitions and how
4421 The new command `macro expand EXPRESSION' expands any macro
4422 invocations in expression, and shows the result.
4424 The new command `show macro MACRO-NAME' shows the definition of the
4425 macro named MACRO-NAME, and where it was defined.
4427 Most compilers don't include information about macros in the debugging
4428 information by default. In GCC 3.1, for example, you need to compile
4429 your program with the options `-gdwarf-2 -g3'. If the macro
4430 information is present in the executable, GDB will read it.
4432 * Multi-arched targets.
4434 DEC Alpha (partial) alpha*-*-*
4435 DEC VAX (partial) vax-*-*
4437 National Semiconductor NS32000 (partial) ns32k-*-*
4438 Motorola 68000 (partial) m68k-*-*
4439 Motorola MCORE mcore-*-*
4443 Fujitsu FRV architecture added by Red Hat frv*-*-*
4446 * New native configurations
4448 Alpha NetBSD alpha*-*-netbsd*
4449 SH NetBSD sh*-*-netbsdelf*
4450 MIPS NetBSD mips*-*-netbsd*
4451 UltraSPARC NetBSD sparc64-*-netbsd*
4453 * OBSOLETE configurations and files
4455 Configurations that have been declared obsolete in this release have
4456 been commented out. Unless there is activity to revive these
4457 configurations, the next release of GDB will have their sources
4458 permanently REMOVED.
4460 Mitsubishi D30V d30v-*-*
4461 OS/9000 i[34]86-*-os9k
4462 IBM AIX PS/2 i[3456]86-*-aix
4463 Fujitsu FR30 fr30-*-elf*
4464 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4465 Argonaut Risc Chip (ARC) arc-*-*
4466 i386 running Mach 3.0 i[3456]86-*-mach3*
4467 i386 running Mach i[3456]86-*-mach*
4468 i386 running OSF/1 i[3456]86-*osf1mk*
4469 HP/Apollo 68k Family m68*-apollo*-sysv*,
4471 m68*-hp-bsd*, m68*-hp-hpux*
4472 I960 with MON960 i960-*-coff
4474 * OBSOLETE languages
4476 CHILL, a Pascal like language used by telecommunications companies.
4478 * REMOVED configurations and files
4480 AMD 29k family via UDI a29k-amd-udi, udi29k
4481 A29K VxWorks a29k-*-vxworks
4482 AMD 29000 embedded, using EBMON a29k-none-none
4483 AMD 29000 embedded with COFF a29k-none-coff
4484 AMD 29000 embedded with a.out a29k-none-aout
4486 testsuite/gdb.hp/gdb.threads-hp/ directory
4488 * New command "set max-user-call-depth <nnn>"
4490 This command allows the user to limit the call depth of user-defined
4491 commands. The default is 1024.
4493 * Changes in FreeBSD/i386 native debugging.
4495 Support for the "generate-core-file" has been added.
4497 * New commands "dump", "append", and "restore".
4499 These commands allow data to be copied from target memory
4500 to a bfd-format or binary file (dump and append), and back
4501 from a file into memory (restore).
4503 * Improved "next/step" support on multi-processor Alpha Tru64.
4505 The previous single-step mechanism could cause unpredictable problems,
4506 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4507 of a software single-step mechanism prevents this.
4509 *** Changes in GDB 5.2.1:
4517 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4518 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4519 Fix, by Joel Brobecker imported from mainline.
4521 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4522 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4523 Fix, by Fred Fish, imported from mainline.
4525 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4526 Surprisingly enough, it works now.
4527 By Michal Ludvig, imported from mainline.
4529 i386 hardware watchpoint support:
4530 avoid misses on second run for some targets.
4531 By Pierre Muller, imported from mainline.
4533 *** Changes in GDB 5.2:
4535 * New command "set trust-readonly-sections on[off]".
4537 This command is a hint that tells gdb that read-only sections
4538 really are read-only (ie. that their contents will not change).
4539 In this mode, gdb will go to the object file rather than the
4540 target to read memory from read-only sections (such as ".text").
4541 This can be a significant performance improvement on some
4542 (notably embedded) targets.
4544 * New command "generate-core-file" (or "gcore").
4546 This new gdb command allows the user to drop a core file of the child
4547 process state at any time. So far it's been implemented only for
4548 GNU/Linux and Solaris, but should be relatively easily ported to other
4549 hosts. Argument is core file name (defaults to core.<pid>).
4551 * New command line option
4553 GDB now accepts --pid or -p followed by a process id.
4555 * Change in command line behavior -- corefiles vs. process ids.
4557 There is a subtle behavior in the way in which GDB handles
4558 command line arguments. The first non-flag argument is always
4559 a program to debug, but the second non-flag argument may either
4560 be a corefile or a process id. Previously, GDB would attempt to
4561 open the second argument as a corefile, and if that failed, would
4562 issue a superfluous error message and then attempt to attach it as
4563 a process. Now, if the second argument begins with a non-digit,
4564 it will be treated as a corefile. If it begins with a digit,
4565 GDB will attempt to attach it as a process, and if no such process
4566 is found, will then attempt to open it as a corefile.
4568 * Changes in ARM configurations.
4570 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4571 configuration is fully multi-arch.
4573 * New native configurations
4575 ARM NetBSD arm*-*-netbsd*
4576 x86 OpenBSD i[3456]86-*-openbsd*
4577 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4578 Sparc64 running FreeBSD sparc64-*-freebsd*
4582 Sanyo XStormy16 xstormy16-elf
4584 * OBSOLETE configurations and files
4586 Configurations that have been declared obsolete in this release have
4587 been commented out. Unless there is activity to revive these
4588 configurations, the next release of GDB will have their sources
4589 permanently REMOVED.
4591 AMD 29k family via UDI a29k-amd-udi, udi29k
4592 A29K VxWorks a29k-*-vxworks
4593 AMD 29000 embedded, using EBMON a29k-none-none
4594 AMD 29000 embedded with COFF a29k-none-coff
4595 AMD 29000 embedded with a.out a29k-none-aout
4597 testsuite/gdb.hp/gdb.threads-hp/ directory
4599 * REMOVED configurations and files
4601 TI TMS320C80 tic80-*-*
4603 PowerPC Solaris powerpcle-*-solaris*
4604 PowerPC Windows NT powerpcle-*-cygwin32
4605 PowerPC Netware powerpc-*-netware*
4606 Harris/CXUX m88k m88*-harris-cxux*
4607 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4608 ns32k-utek-sysv* ns32k-utek-*
4609 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4610 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4611 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4612 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4613 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4615 * Changes to command line processing
4617 The new `--args' feature can be used to specify command-line arguments
4618 for the inferior from gdb's command line.
4620 * Changes to key bindings
4622 There is a new `operate-and-get-next' function bound to `C-o'.
4624 *** Changes in GDB 5.1.1
4626 Fix compile problem on DJGPP.
4628 Fix a problem with floating-point registers on the i386 being
4631 Fix to stop GDB crashing on .debug_str debug info.
4633 Numerous documentation fixes.
4635 Numerous testsuite fixes.
4637 *** Changes in GDB 5.1:
4639 * New native configurations
4641 Alpha FreeBSD alpha*-*-freebsd*
4642 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4643 MIPS GNU/Linux mips*-*-linux*
4644 MIPS SGI Irix 6.x mips*-sgi-irix6*
4645 ia64 AIX ia64-*-aix*
4646 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4650 Motorola 68HC11 and 68HC12 m68hc11-elf
4652 UltraSparc running GNU/Linux sparc64-*-linux*
4654 * OBSOLETE configurations and files
4656 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4657 Harris/CXUX m88k m88*-harris-cxux*
4658 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4659 ns32k-utek-sysv* ns32k-utek-*
4660 TI TMS320C80 tic80-*-*
4662 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4663 PowerPC Solaris powerpcle-*-solaris*
4664 PowerPC Windows NT powerpcle-*-cygwin32
4665 PowerPC Netware powerpc-*-netware*
4666 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4667 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4668 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4669 Apple Macintosh (MPW) host N/A
4671 stuff.c (Program to stuff files into a specially prepared space in kdb)
4672 kdb-start.c (Main loop for the standalone kernel debugger)
4674 Configurations that have been declared obsolete in this release have
4675 been commented out. Unless there is activity to revive these
4676 configurations, the next release of GDB will have their sources
4677 permanently REMOVED.
4679 * REMOVED configurations and files
4681 Altos 3068 m68*-altos-*
4682 Convex c1-*-*, c2-*-*
4684 ARM RISCix arm-*-* (as host)
4688 * GDB has been converted to ISO C.
4690 GDB's source code has been converted to ISO C. In particular, the
4691 sources are fully protoized, and rely on standard headers being
4696 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4698 * The MI enabled by default.
4700 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4701 revised and enabled by default. Packages which use GDB as a debugging
4702 engine behind a UI or another front end are encouraged to switch to
4703 using the GDB/MI interface, instead of the old annotations interface
4704 which is now deprecated.
4706 * Support for debugging Pascal programs.
4708 GDB now includes support for debugging Pascal programs. The following
4709 main features are supported:
4711 - Pascal-specific data types such as sets;
4713 - automatic recognition of Pascal sources based on file-name
4716 - Pascal-style display of data types, variables, and functions;
4718 - a Pascal expression parser.
4720 However, some important features are not yet supported.
4722 - Pascal string operations are not supported at all;
4724 - there are some problems with boolean types;
4726 - Pascal type hexadecimal constants are not supported
4727 because they conflict with the internal variables format;
4729 - support for Pascal objects and classes is not full yet;
4731 - unlike Pascal, GDB is case-sensitive for symbol names.
4733 * Changes in completion.
4735 Commands such as `shell', `run' and `set args', which pass arguments
4736 to inferior programs, now complete on file names, similar to what
4737 users expect at the shell prompt.
4739 Commands which accept locations, such as `disassemble', `print',
4740 `breakpoint', `until', etc. now complete on filenames as well as
4741 program symbols. Thus, if you type "break foob TAB", and the source
4742 files linked into the programs include `foobar.c', that file name will
4743 be one of the candidates for completion. However, file names are not
4744 considered for completion after you typed a colon that delimits a file
4745 name from a name of a function in that file, as in "break foo.c:bar".
4747 `set demangle-style' completes on available demangling styles.
4749 * New platform-independent commands:
4751 It is now possible to define a post-hook for a command as well as a
4752 hook that runs before the command. For more details, see the
4753 documentation of `hookpost' in the GDB manual.
4755 * Changes in GNU/Linux native debugging.
4757 Support for debugging multi-threaded programs has been completely
4758 revised for all platforms except m68k and sparc. You can now debug as
4759 many threads as your system allows you to have.
4761 Attach/detach is supported for multi-threaded programs.
4763 Support for SSE registers was added for x86. This doesn't work for
4764 multi-threaded programs though.
4766 * Changes in MIPS configurations.
4768 Multi-arch support is enabled for all MIPS configurations.
4770 GDB can now be built as native debugger on SGI Irix 6.x systems for
4771 debugging n32 executables. (Debugging 64-bit executables is not yet
4774 * Unified support for hardware watchpoints in all x86 configurations.
4776 Most (if not all) native x86 configurations support hardware-assisted
4777 breakpoints and watchpoints in a unified manner. This support
4778 implements debug register sharing between watchpoints, which allows to
4779 put a virtually infinite number of watchpoints on the same address,
4780 and also supports watching regions up to 16 bytes with several debug
4783 The new maintenance command `maintenance show-debug-regs' toggles
4784 debugging print-outs in functions that insert, remove, and test
4785 watchpoints and hardware breakpoints.
4787 * Changes in the DJGPP native configuration.
4789 New command ``info dos sysinfo'' displays assorted information about
4790 the CPU, OS, memory, and DPMI server.
4792 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4793 display information about segment descriptors stored in GDT, LDT, and
4796 New commands ``info dos pde'' and ``info dos pte'' display entries
4797 from Page Directory and Page Tables (for now works with CWSDPMI only).
4798 New command ``info dos address-pte'' displays the Page Table entry for
4799 a given linear address.
4801 GDB can now pass command lines longer than 126 characters to the
4802 program being debugged (requires an update to the libdbg.a library
4803 which is part of the DJGPP development kit).
4805 DWARF2 debug info is now supported.
4807 It is now possible to `step' and `next' through calls to `longjmp'.
4809 * Changes in documentation.
4811 All GDB documentation was converted to GFDL, the GNU Free
4812 Documentation License.
4814 Tracepoints-related commands are now fully documented in the GDB
4817 TUI, the Text-mode User Interface, is now documented in the manual.
4819 Tracepoints-related commands are now fully documented in the GDB
4822 The "GDB Internals" manual now has an index. It also includes
4823 documentation of `ui_out' functions, GDB coding standards, x86
4824 hardware watchpoints, and memory region attributes.
4826 * GDB's version number moved to ``version.in''
4828 The Makefile variable VERSION has been replaced by the file
4829 ``version.in''. People creating GDB distributions should update the
4830 contents of this file.
4834 GUD support is now a standard part of the EMACS distribution.
4836 *** Changes in GDB 5.0:
4838 * Improved support for debugging FP programs on x86 targets
4840 Unified and much-improved support for debugging floating-point
4841 programs on all x86 targets. In particular, ``info float'' now
4842 displays the FP registers in the same format on all x86 targets, with
4843 greater level of detail.
4845 * Improvements and bugfixes in hardware-assisted watchpoints
4847 It is now possible to watch array elements, struct members, and
4848 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4849 on x86 targets no longer erroneously trigger when the address is
4852 * Improvements in the native DJGPP version of GDB
4854 The distribution now includes all the scripts and auxiliary files
4855 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4856 machines ``out of the box''.
4858 The DJGPP version can now debug programs that use signals. It is
4859 possible to catch signals that happened in the debuggee, deliver
4860 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4861 would kill the program being debugged.) Programs that hook hardware
4862 interrupts (keyboard, timer, etc.) can also be debugged.
4864 It is now possible to debug DJGPP programs that redirect their
4865 standard handles or switch them to raw (as opposed to cooked) mode, or
4866 even close them. The command ``run < foo > bar'' works as expected,
4867 and ``info terminal'' reports useful information about the debuggee's
4868 terminal, including raw/cooked mode, redirection, etc.
4870 The DJGPP version now uses termios functions for console I/O, which
4871 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4874 DOS-style file names with drive letters are now fully supported by
4877 It is now possible to debug DJGPP programs that switch their working
4878 directory. It is also possible to rerun the debuggee any number of
4879 times without restarting GDB; thus, you can use the same setup,
4880 breakpoints, etc. for many debugging sessions.
4882 * New native configurations
4884 ARM GNU/Linux arm*-*-linux*
4885 PowerPC GNU/Linux powerpc-*-linux*
4889 Motorola MCore mcore-*-*
4890 x86 VxWorks i[3456]86-*-vxworks*
4891 PowerPC VxWorks powerpc-*-vxworks*
4892 TI TMS320C80 tic80-*-*
4894 * OBSOLETE configurations
4896 Altos 3068 m68*-altos-*
4897 Convex c1-*-*, c2-*-*
4899 ARM RISCix arm-*-* (as host)
4902 Configurations that have been declared obsolete will be commented out,
4903 but the code will be left in place. If there is no activity to revive
4904 these configurations before the next release of GDB, the sources will
4905 be permanently REMOVED.
4907 * Gould support removed
4909 Support for the Gould PowerNode and NP1 has been removed.
4911 * New features for SVR4
4913 On SVR4 native platforms (such as Solaris), if you attach to a process
4914 without first loading a symbol file, GDB will now attempt to locate and
4915 load symbols from the running process's executable file.
4917 * Many C++ enhancements
4919 C++ support has been greatly improved. Overload resolution now works properly
4920 in almost all cases. RTTI support is on the way.
4922 * Remote targets can connect to a sub-program
4924 A popen(3) style serial-device has been added. This device starts a
4925 sub-process (such as a stand-alone simulator) and then communicates
4926 with that. The sub-program to run is specified using the syntax
4927 ``|<program> <args>'' vis:
4929 (gdb) set remotedebug 1
4930 (gdb) target extended-remote |mn10300-elf-sim program-args
4932 * MIPS 64 remote protocol
4934 A long standing bug in the mips64 remote protocol where by GDB
4935 expected certain 32 bit registers (ex SR) to be transfered as 32
4936 instead of 64 bits has been fixed.
4938 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4939 added to provide backward compatibility with older versions of GDB.
4941 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4943 The command ``set remotebinarydownload'' command has been replaced by
4944 ``set remote X-packet''. Other commands in ``set remote'' family
4945 include ``set remote P-packet''.
4947 * Breakpoint commands accept ranges.
4949 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4950 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4951 ``tracepoint passcount'' also accepts a range of tracepoints.
4953 * ``apropos'' command added.
4955 The ``apropos'' command searches through command names and
4956 documentation strings, printing out matches, making it much easier to
4957 try to find a command that does what you are looking for.
4961 A new machine oriented interface (MI) has been added to GDB. This
4962 interface is designed for debug environments running GDB as a separate
4963 process. This is part of the long term libGDB project. See the
4964 "GDB/MI" chapter of the GDB manual for further information. It can be
4965 enabled by configuring with:
4967 .../configure --enable-gdbmi
4969 *** Changes in GDB-4.18:
4971 * New native configurations
4973 HP-UX 10.20 hppa*-*-hpux10.20
4974 HP-UX 11.x hppa*-*-hpux11.0*
4975 M68K GNU/Linux m68*-*-linux*
4979 Fujitsu FR30 fr30-*-elf*
4980 Intel StrongARM strongarm-*-*
4981 Mitsubishi D30V d30v-*-*
4983 * OBSOLETE configurations
4985 Gould PowerNode, NP1 np1-*-*, pn-*-*
4987 Configurations that have been declared obsolete will be commented out,
4988 but the code will be left in place. If there is no activity to revive
4989 these configurations before the next release of GDB, the sources will
4990 be permanently REMOVED.
4994 As a compatibility experiment, GDB's source files buildsym.h and
4995 buildsym.c have been converted to pure standard C, no longer
4996 containing any K&R compatibility code. We believe that all systems in
4997 use today either come with a standard C compiler, or have a GCC port
4998 available. If this is not true, please report the affected
4999 configuration to bug-gdb@gnu.org immediately. See the README file for
5000 information about getting a standard C compiler if you don't have one
5005 GDB now uses readline 2.2.
5007 * set extension-language
5009 You can now control the mapping between filename extensions and source
5010 languages by using the `set extension-language' command. For instance,
5011 you can ask GDB to treat .c files as C++ by saying
5012 set extension-language .c c++
5013 The command `info extensions' lists all of the recognized extensions
5014 and their associated languages.
5016 * Setting processor type for PowerPC and RS/6000
5018 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5019 you can use the `set processor' command to specify what variant of the
5020 PowerPC family you are debugging. The command
5024 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5025 following PowerPC and RS6000 variants:
5027 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5028 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5030 403GC IBM PowerPC 403GC
5031 505 Motorola PowerPC 505
5032 860 Motorola PowerPC 860 or 850
5033 601 Motorola PowerPC 601
5034 602 Motorola PowerPC 602
5035 603 Motorola/IBM PowerPC 603 or 603e
5036 604 Motorola PowerPC 604 or 604e
5037 750 Motorola/IBM PowerPC 750 or 750
5039 At the moment, this command just tells GDB what to name the
5040 special-purpose processor registers. Since almost all the affected
5041 registers are inaccessible to user-level programs, this command is
5042 only useful for remote debugging in its present form.
5046 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5047 more extensive support for HP-UX. Added features include shared
5048 library support, kernel threads and hardware watchpoints for 11.00,
5049 support for HP's ANSI C and C++ compilers, and a compatibility mode
5050 for xdb and dbx commands.
5054 HP's donation includes the new concept of catchpoints, which is a
5055 generalization of the old catch command. On HP-UX, it is now possible
5056 to catch exec, fork, and vfork, as well as library loading.
5058 This means that the existing catch command has changed; its first
5059 argument now specifies the type of catch to be set up. See the
5060 output of "help catch" for a list of catchpoint types.
5062 * Debugging across forks
5064 On HP-UX, you can choose which process to debug when a fork() happens
5069 HP has donated a curses-based terminal user interface (TUI). To get
5070 it, build with --enable-tui. Although this can be enabled for any
5071 configuration, at present it only works for native HP debugging.
5073 * GDB remote protocol additions
5075 A new protocol packet 'X' that writes binary data is now available.
5076 Default behavior is to try 'X', then drop back to 'M' if the stub
5077 fails to respond. The settable variable `remotebinarydownload'
5078 allows explicit control over the use of 'X'.
5080 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5081 full 64-bit address. The command
5083 set remoteaddresssize 32
5085 can be used to revert to the old behaviour. For existing remote stubs
5086 the change should not be noticed, as the additional address information
5089 In order to assist in debugging stubs, you may use the maintenance
5090 command `packet' to send any text string to the stub. For instance,
5092 maint packet heythere
5094 sends the packet "$heythere#<checksum>". Note that it is very easy to
5095 disrupt a debugging session by sending the wrong packet at the wrong
5098 The compare-sections command allows you to compare section data on the
5099 target to what is in the executable file without uploading or
5100 downloading, by comparing CRC checksums.
5102 * Tracing can collect general expressions
5104 You may now collect general expressions at tracepoints. This requires
5105 further additions to the target-side stub; see tracepoint.c and
5106 doc/agentexpr.texi for further details.
5108 * mask-address variable for Mips
5110 For Mips targets, you may control the zeroing of the upper 32 bits of
5111 a 64-bit address by entering `set mask-address on'. This is mainly
5112 of interest to users of embedded R4xxx and R5xxx processors.
5114 * Higher serial baud rates
5116 GDB's serial code now allows you to specify baud rates 57600, 115200,
5117 230400, and 460800 baud. (Note that your host system may not be able
5118 to achieve all of these rates.)
5122 The i960 configuration now includes an initial implementation of a
5123 builtin simulator, contributed by Jim Wilson.
5126 *** Changes in GDB-4.17:
5128 * New native configurations
5130 Alpha GNU/Linux alpha*-*-linux*
5131 Unixware 2.x i[3456]86-unixware2*
5132 Irix 6.x mips*-sgi-irix6*
5133 PowerPC GNU/Linux powerpc-*-linux*
5134 PowerPC Solaris powerpcle-*-solaris*
5135 Sparc GNU/Linux sparc-*-linux*
5136 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5140 Argonaut Risc Chip (ARC) arc-*-*
5141 Hitachi H8/300S h8300*-*-*
5142 Matsushita MN10200 w/simulator mn10200-*-*
5143 Matsushita MN10300 w/simulator mn10300-*-*
5144 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5145 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5146 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5147 Mitsubishi D10V w/simulator d10v-*-*
5148 Mitsubishi M32R/D w/simulator m32r-*-elf*
5149 Tsqware Sparclet sparclet-*-*
5150 NEC V850 w/simulator v850-*-*
5152 * New debugging protocols
5154 ARM with RDI protocol arm*-*-*
5155 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5156 DDB and LSI variants of PMON protocol mips*-*-*
5157 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5158 PowerPC with SDS protocol powerpc{,le}-*-eabi
5159 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5163 All configurations can now understand and use the DWARF 2 debugging
5164 format. The choice is automatic, if the symbol file contains DWARF 2
5169 GDB now includes basic Java language support. This support is
5170 only useful with Java compilers that produce native machine code.
5172 * solib-absolute-prefix and solib-search-path
5174 For SunOS and SVR4 shared libraries, you may now set the prefix for
5175 loading absolute shared library symbol files, and the search path for
5176 locating non-absolute shared library symbol files.
5178 * Live range splitting
5180 GDB can now effectively debug code for which GCC has performed live
5181 range splitting as part of its optimization. See gdb/doc/LRS for
5182 more details on the expected format of the stabs information.
5186 GDB's support for the GNU Hurd, including thread debugging, has been
5187 updated to work with current versions of the Hurd.
5191 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5192 instruction set. ARM GDB automatically detects when Thumb
5193 instructions are in use, and adjusts disassembly and backtracing
5198 GDB's MIPS target configurations now handle the MIP16 16-bit
5203 GDB now includes support for overlays; if an executable has been
5204 linked such that multiple sections are based at the same address, GDB
5205 will decide which section to use for symbolic info. You can choose to
5206 control the decision manually, using overlay commands, or implement
5207 additional target-side support and use "overlay load-target" to bring
5208 in the overlay mapping. Do "help overlay" for more detail.
5212 The command "info symbol <address>" displays information about
5213 the symbol at the specified address.
5217 The standard remote protocol now includes an extension that allows
5218 asynchronous collection and display of trace data. This requires
5219 extensive support in the target-side debugging stub. Tracing mode
5220 includes a new interaction mode in GDB and new commands: see the
5221 file tracepoint.c for more details.
5225 Configurations for embedded MIPS now include a simulator contributed
5226 by Cygnus Solutions. The simulator supports the instruction sets
5227 of most MIPS variants.
5231 Sparc configurations may now include the ERC32 simulator contributed
5232 by the European Space Agency. The simulator is not built into
5233 Sparc targets by default; configure with --enable-sim to include it.
5237 For target configurations that may include multiple variants of a
5238 basic architecture (such as MIPS and SH), you may now set the
5239 architecture explicitly. "set arch" sets, "info arch" lists
5240 the possible architectures.
5242 *** Changes in GDB-4.16:
5244 * New native configurations
5246 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5247 M68K NetBSD m68k-*-netbsd*
5248 PowerPC AIX 4.x powerpc-*-aix*
5249 PowerPC MacOS powerpc-*-macos*
5250 PowerPC Windows NT powerpcle-*-cygwin32
5251 RS/6000 AIX 4.x rs6000-*-aix4*
5255 ARM with RDP protocol arm-*-*
5256 I960 with MON960 i960-*-coff
5257 MIPS VxWorks mips*-*-vxworks*
5258 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5259 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5261 Matra Sparclet sparclet-*-*
5265 The powerpc-eabi configuration now includes the PSIM simulator,
5266 contributed by Andrew Cagney, with assistance from Mike Meissner.
5267 PSIM is a very elaborate model of the PowerPC, including not only
5268 basic instruction set execution, but also details of execution unit
5269 performance and I/O hardware. See sim/ppc/README for more details.
5273 GDB now works with Solaris 2.5.
5275 * Windows 95/NT native
5277 GDB will now work as a native debugger on Windows 95 and Windows NT.
5278 To build it from source, you must use the "gnu-win32" environment,
5279 which uses a DLL to emulate enough of Unix to run the GNU tools.
5280 Further information, binaries, and sources are available at
5281 ftp.cygnus.com, under pub/gnu-win32.
5283 * dont-repeat command
5285 If a user-defined command includes the command `dont-repeat', then the
5286 command will not be repeated if the user just types return. This is
5287 useful if the command is time-consuming to run, so that accidental
5288 extra keystrokes don't run the same command many times.
5290 * Send break instead of ^C
5292 The standard remote protocol now includes an option to send a break
5293 rather than a ^C to the target in order to interrupt it. By default,
5294 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5296 * Remote protocol timeout
5298 The standard remote protocol includes a new variable `remotetimeout'
5299 that allows you to set the number of seconds before GDB gives up trying
5300 to read from the target. The default value is 2.
5302 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5304 By default GDB will automatically keep track of objects as they are
5305 loaded and unloaded by the dynamic linker. By using the command `set
5306 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5307 when shared library events occur, thus allowing you to set breakpoints
5308 in shared libraries which are explicitly loaded by the inferior.
5310 Note this feature does not work on hpux8. On hpux9 you must link
5311 /usr/lib/end.o into your program. This feature should work
5312 automatically on hpux10.
5314 * Irix 5.x hardware watchpoint support
5316 Irix 5 configurations now support the use of hardware watchpoints.
5318 * Mips protocol "SYN garbage limit"
5320 When debugging a Mips target using the `target mips' protocol, you
5321 may set the number of characters that GDB will ignore by setting
5322 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5323 every character. The default value is 1050.
5325 * Recording and replaying remote debug sessions
5327 If you set `remotelogfile' to the name of a file, gdb will write to it
5328 a recording of a remote debug session. This recording may then be
5329 replayed back to gdb using "gdbreplay". See gdbserver/README for
5330 details. This is useful when you have a problem with GDB while doing
5331 remote debugging; you can make a recording of the session and send it
5332 to someone else, who can then recreate the problem.
5334 * Speedups for remote debugging
5336 GDB includes speedups for downloading and stepping MIPS systems using
5337 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5338 and more efficient S-record downloading.
5340 * Memory use reductions and statistics collection
5342 GDB now uses less memory and reports statistics about memory usage.
5343 Try the `maint print statistics' command, for example.
5345 *** Changes in GDB-4.15:
5347 * Psymtabs for XCOFF
5349 The symbol reader for AIX GDB now uses partial symbol tables. This
5350 can greatly improve startup time, especially for large executables.
5352 * Remote targets use caching
5354 Remote targets now use a data cache to speed up communication with the
5355 remote side. The data cache could lead to incorrect results because
5356 it doesn't know about volatile variables, thus making it impossible to
5357 debug targets which use memory mapped I/O devices. `set remotecache
5358 off' turns the the data cache off.
5360 * Remote targets may have threads
5362 The standard remote protocol now includes support for multiple threads
5363 in the target system, using new protocol commands 'H' and 'T'. See
5364 gdb/remote.c for details.
5368 If GDB is configured with `--enable-netrom', then it will include
5369 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5370 acts as though it is a bank of ROM on the target board, but you can
5371 write into it over the network. GDB's support consists only of
5372 support for fast loading into the emulated ROM; to debug, you must use
5373 another protocol, such as standard remote protocol. The usual
5374 sequence is something like
5376 target nrom <netrom-hostname>
5378 target remote <netrom-hostname>:1235
5382 GDB now includes support for the Apple Macintosh, as a host only. It
5383 may be run as either an MPW tool or as a standalone application, and
5384 it can debug through the serial port. All the usual GDB commands are
5385 available, but to the target command, you must supply "serial" as the
5386 device type instead of "/dev/ttyXX". See mpw-README in the main
5387 directory for more information on how to build. The MPW configuration
5388 scripts */mpw-config.in support only a few targets, and only the
5389 mips-idt-ecoff target has been tested.
5393 GDB configuration now uses autoconf. This is not user-visible,
5394 but does simplify configuration and building.
5398 GDB now supports hpux10.
5400 *** Changes in GDB-4.14:
5402 * New native configurations
5404 x86 FreeBSD i[345]86-*-freebsd
5405 x86 NetBSD i[345]86-*-netbsd
5406 NS32k NetBSD ns32k-*-netbsd
5407 Sparc NetBSD sparc-*-netbsd
5411 A29K VxWorks a29k-*-vxworks
5412 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5413 CPU32 EST-300 emulator m68*-*-est*
5414 PowerPC ELF powerpc-*-elf
5417 * Alpha OSF/1 support for procfs
5419 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5420 possible to attach to running processes. As the mounting of the /proc
5421 filesystem is optional on the Alpha, GDB automatically determines
5422 the availability of /proc during startup. This can lead to problems
5423 if /proc is unmounted after GDB has been started.
5425 * Arguments to user-defined commands
5427 User commands may accept up to 10 arguments separated by whitespace.
5428 Arguments are accessed within the user command via $arg0..$arg9. A
5431 print $arg0 + $arg1 + $arg2
5433 To execute the command use:
5436 Defines the command "adder" which prints the sum of its three arguments.
5437 Note the arguments are text substitutions, so they may reference variables,
5438 use complex expressions, or even perform inferior function calls.
5440 * New `if' and `while' commands
5442 This makes it possible to write more sophisticated user-defined
5443 commands. Both commands take a single argument, which is the
5444 expression to evaluate, and must be followed by the commands to
5445 execute, one per line, if the expression is nonzero, the list being
5446 terminated by the word `end'. The `if' command list may include an
5447 `else' word, which causes the following commands to be executed only
5448 if the expression is zero.
5450 * Fortran source language mode
5452 GDB now includes partial support for Fortran 77. It will recognize
5453 Fortran programs and can evaluate a subset of Fortran expressions, but
5454 variables and functions may not be handled correctly. GDB will work
5455 with G77, but does not yet know much about symbols emitted by other
5458 * Better HPUX support
5460 Most debugging facilities now work on dynamic executables for HPPAs
5461 running hpux9 or later. You can attach to running dynamically linked
5462 processes, but by default the dynamic libraries will be read-only, so
5463 for instance you won't be able to put breakpoints in them. To change
5464 that behavior do the following before running the program:
5470 This will cause the libraries to be mapped private and read-write.
5471 To revert to the normal behavior, do this:
5477 You cannot set breakpoints or examine data in the library until after
5478 the library is loaded if the function/data symbols do not have
5481 GDB can now also read debug symbols produced by the HP C compiler on
5482 HPPAs (sorry, no C++, Fortran or 68k support).
5484 * Target byte order now dynamically selectable
5486 You can choose which byte order to use with a target system, via the
5487 commands "set endian big" and "set endian little", and you can see the
5488 current setting by using "show endian". You can also give the command
5489 "set endian auto", in which case GDB will use the byte order
5490 associated with the executable. Currently, only embedded MIPS
5491 configurations support dynamic selection of target byte order.
5493 * New DOS host serial code
5495 This version uses DPMI interrupts to handle buffered I/O, so you
5496 no longer need to run asynctsr when debugging boards connected to
5499 *** Changes in GDB-4.13:
5501 * New "complete" command
5503 This lists all the possible completions for the rest of the line, if it
5504 were to be given as a command itself. This is intended for use by emacs.
5506 * Trailing space optional in prompt
5508 "set prompt" no longer adds a space for you after the prompt you set. This
5509 allows you to set a prompt which ends in a space or one that does not.
5511 * Breakpoint hit counts
5513 "info break" now displays a count of the number of times the breakpoint
5514 has been hit. This is especially useful in conjunction with "ignore"; you
5515 can ignore a large number of breakpoint hits, look at the breakpoint info
5516 to see how many times the breakpoint was hit, then run again, ignoring one
5517 less than that number, and this will get you quickly to the last hit of
5520 * Ability to stop printing at NULL character
5522 "set print null-stop" will cause GDB to stop printing the characters of
5523 an array when the first NULL is encountered. This is useful when large
5524 arrays actually contain only short strings.
5526 * Shared library breakpoints
5528 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5529 breakpoints in shared libraries before the executable is run.
5531 * Hardware watchpoints
5533 There is a new hardware breakpoint for the watch command for sparclite
5534 targets. See gdb/sparclite/hw_breakpoint.note.
5536 Hardware watchpoints are also now supported under GNU/Linux.
5540 Annotations have been added. These are for use with graphical interfaces,
5541 and are still experimental. Currently only gdba.el uses these.
5543 * Improved Irix 5 support
5545 GDB now works properly with Irix 5.2.
5547 * Improved HPPA support
5549 GDB now works properly with the latest GCC and GAS.
5551 * New native configurations
5553 Sequent PTX4 i[34]86-sequent-ptx4
5554 HPPA running OSF/1 hppa*-*-osf*
5555 Atari TT running SVR4 m68*-*-sysv4*
5556 RS/6000 LynxOS rs6000-*-lynxos*
5560 OS/9000 i[34]86-*-os9k
5561 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5564 * Hitachi SH7000 and E7000-PC ICE support
5566 There is now support for communicating with the Hitachi E7000-PC ICE.
5567 This is available automatically when GDB is configured for the SH.
5571 As usual, a variety of small fixes and improvements, both generic
5572 and configuration-specific. See the ChangeLog for more detail.
5574 *** Changes in GDB-4.12:
5576 * Irix 5 is now supported
5580 GDB-4.12 on the HPPA has a number of changes which make it unable
5581 to debug the output from the currently released versions of GCC and
5582 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5583 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5584 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5587 *** Changes in GDB-4.11:
5589 * User visible changes:
5593 The "set remotedebug" option is now consistent between the mips remote
5594 target, remote targets using the gdb-specific protocol, UDI (AMD's
5595 debug protocol for the 29k) and the 88k bug monitor. It is now an
5596 integer specifying a debug level (normally 0 or 1, but 2 means more
5597 debugging info for the mips target).
5599 * DEC Alpha native support
5601 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5602 debug info, but GDB works fairly well with the DEC compiler and should
5603 work with a future GCC release. See the README file for a few
5604 Alpha-specific notes.
5606 * Preliminary thread implementation
5608 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5610 * LynxOS native and target support for 386
5612 This release has been hosted on LynxOS 2.2, and also can be configured
5613 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5616 * Improvements in C++ mangling/demangling.
5618 This release has much better g++ debugging, specifically in name
5619 mangling/demangling, virtual function calls, print virtual table,
5620 call methods, ...etc.
5622 *** Changes in GDB-4.10:
5624 * User visible changes:
5626 Remote debugging using the GDB-specific (`target remote') protocol now
5627 supports the `load' command. This is only useful if you have some
5628 other way of getting the stub to the target system, and you can put it
5629 somewhere in memory where it won't get clobbered by the download.
5631 Filename completion now works.
5633 When run under emacs mode, the "info line" command now causes the
5634 arrow to point to the line specified. Also, "info line" prints
5635 addresses in symbolic form (as well as hex).
5637 All vxworks based targets now support a user settable option, called
5638 vxworks-timeout. This option represents the number of seconds gdb
5639 should wait for responses to rpc's. You might want to use this if
5640 your vxworks target is, perhaps, a slow software simulator or happens
5641 to be on the far side of a thin network line.
5645 This release contains support for using a DEC alpha as a GDB host for
5646 cross debugging. Native alpha debugging is not supported yet.
5649 *** Changes in GDB-4.9:
5653 This is the first GDB release which is accompanied by a matching testsuite.
5654 The testsuite requires installation of dejagnu, which should be available
5655 via ftp from most sites that carry GNU software.
5659 'Cfront' style demangling has had its name changed to 'ARM' style, to
5660 emphasize that it was written from the specifications in the C++ Annotated
5661 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5662 disclaimers, it still generated too much confusion with users attempting to
5663 use gdb with AT&T cfront.
5667 GDB now uses a standard remote interface to a simulator library.
5668 So far, the library contains simulators for the Zilog Z8001/2, the
5669 Hitachi H8/300, H8/500 and Super-H.
5671 * New targets supported
5673 H8/300 simulator h8300-hitachi-hms or h8300hms
5674 H8/500 simulator h8500-hitachi-hms or h8500hms
5675 SH simulator sh-hitachi-hms or sh
5676 Z8000 simulator z8k-zilog-none or z8ksim
5677 IDT MIPS board over serial line mips-idt-ecoff
5679 Cross-debugging to GO32 targets is supported. It requires a custom
5680 version of the i386-stub.c module which is integrated with the
5681 GO32 memory extender.
5683 * New remote protocols
5685 MIPS remote debugging protocol.
5687 * New source languages supported
5689 This version includes preliminary support for Chill, a Pascal like language
5690 used by telecommunications companies. Chill support is also being integrated
5691 into the GNU compiler, but we don't know when it will be publically available.
5694 *** Changes in GDB-4.8:
5696 * HP Precision Architecture supported
5698 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5699 version of this support was available as a set of patches from the
5700 University of Utah. GDB does not support debugging of programs
5701 compiled with the HP compiler, because HP will not document their file
5702 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5703 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5705 Many problems in the preliminary version have been fixed.
5707 * Faster and better demangling
5709 We have improved template demangling and fixed numerous bugs in the GNU style
5710 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5711 character types (wchar_t) are now supported. Demangling of each symbol is now
5712 only done once, and is cached when the symbol table for a file is read in.
5713 This results in a small increase in memory usage for C programs, a moderate
5714 increase in memory usage for C++ programs, and a fantastic speedup in
5717 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5718 from the specifications in the Annotated Reference Manual, which AT&T's
5719 compiler does not actually implement.
5721 * G++ multiple inheritance compiler problem
5723 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5724 inheritance lattices was reworked to properly discover ambiguities. We
5725 recently found an example which causes this new algorithm to fail in a
5726 very subtle way, producing bad debug information for those classes.
5727 The file 'gcc.patch' (in this directory) can be applied to gcc to
5728 circumvent the problem. A future GCC release will contain a complete
5731 The previous G++ debug info problem (mentioned below for the gdb-4.7
5732 release) is fixed in gcc version 2.3.2.
5734 * Improved configure script
5736 The `configure' script will now attempt to guess your system type if
5737 you don't supply a host system type. The old scheme of supplying a
5738 host system triplet is preferable over using this. All the magic is
5739 done in the new `config.guess' script. Examine it for details.
5741 We have also brought our configure script much more in line with the FSF's
5742 version. It now supports the --with-xxx options. In particular,
5743 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5744 The resulting GDB will not be able to read arbitrary object file formats --
5745 only the format ``expected'' to be used on the configured target system.
5746 We hope to make this the default in a future release.
5748 * Documentation improvements
5750 There's new internal documentation on how to modify GDB, and how to
5751 produce clean changes to the code. We implore people to read it
5752 before submitting changes.
5754 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5755 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5756 `info' files are also provided. To build `info' files from scratch,
5757 you will need the latest `makeinfo' release, which will be available in
5758 a future texinfo-X.Y release.
5760 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5761 We're not sure exactly which versions have this problem, but it has
5762 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5763 or better. If that isn't possible, there is a patch in
5764 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5765 around this problem.
5769 GDB now supports array constants that can be used in expressions typed in by
5770 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5771 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5774 The new directory `gdb/sparclite' contains a program that demonstrates
5775 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5777 * New native hosts supported
5779 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5780 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5782 * New targets supported
5784 AMD 29k family via UDI a29k-amd-udi or udi29k
5786 * New file formats supported
5788 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5789 HPUX core files, and SCO 3.2v2 core files.
5793 Attaching to processes now works again; thanks for the many bug reports.
5795 We have also stomped on a bunch of core dumps caused by
5796 printf_filtered("%s") problems.
5798 We eliminated a copyright problem on the rpc and ptrace header files
5799 for VxWorks, which was discovered at the last minute during the 4.7
5800 release. You should now be able to build a VxWorks GDB.
5802 You can now interrupt gdb while an attached process is running. This
5803 will cause the attached process to stop, and give control back to GDB.
5805 We fixed problems caused by using too many file descriptors
5806 for reading symbols from object files and libraries. This was
5807 especially a problem for programs that used many (~100) shared
5810 The `step' command now only enters a subroutine if there is line number
5811 information for the subroutine. Otherwise it acts like the `next'
5812 command. Previously, `step' would enter subroutines if there was
5813 any debugging information about the routine. This avoids problems
5814 when using `cc -g1' on MIPS machines.
5816 * Internal improvements
5818 GDB's internal interfaces have been improved to make it easier to support
5819 debugging of multiple languages in the future.
5821 GDB now uses a common structure for symbol information internally.
5822 Minimal symbols (derived from linkage symbols in object files), partial
5823 symbols (from a quick scan of debug information), and full symbols
5824 contain a common subset of information, making it easier to write
5825 shared code that handles any of them.
5827 * New command line options
5829 We now accept --silent as an alias for --quiet.
5833 The memory-mapped-malloc library is now licensed under the GNU Library
5834 General Public License.
5836 *** Changes in GDB-4.7:
5838 * Host/native/target split
5840 GDB has had some major internal surgery to untangle the support for
5841 hosts and remote targets. Now, when you configure GDB for a remote
5842 target, it will no longer load in all of the support for debugging
5843 local programs on the host. When fully completed and tested, this will
5844 ensure that arbitrary host/target combinations are possible.
5846 The primary conceptual shift is to separate the non-portable code in
5847 GDB into three categories. Host specific code is required any time GDB
5848 is compiled on that host, regardless of the target. Target specific
5849 code relates to the peculiarities of the target, but can be compiled on
5850 any host. Native specific code is everything else: it can only be
5851 built when the host and target are the same system. Child process
5852 handling and core file support are two common `native' examples.
5854 GDB's use of /proc for controlling Unix child processes is now cleaner.
5855 It has been split out into a single module under the `target_ops' vector,
5856 plus two native-dependent functions for each system that uses /proc.
5858 * New hosts supported
5860 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5861 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5862 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5864 * New targets supported
5866 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5867 68030 and CPU32 m68030-*-*, m68332-*-*
5869 * New native hosts supported
5871 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5872 (386bsd is not well tested yet)
5873 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5875 * New file formats supported
5877 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5878 supports reading of `a.out.adobe' object files, which are an a.out
5879 format extended with minimal information about multiple sections.
5883 `show copying' is the same as the old `info copying'.
5884 `show warranty' is the same as `info warrantee'.
5885 These were renamed for consistency. The old commands continue to work.
5887 `info handle' is a new alias for `info signals'.
5889 You can now define pre-command hooks, which attach arbitrary command
5890 scripts to any command. The commands in the hook will be executed
5891 prior to the user's command. You can also create a hook which will be
5892 executed whenever the program stops. See gdb.texinfo.
5896 We now deal with Cfront style name mangling, and can even extract type
5897 info from mangled symbols. GDB can automatically figure out which
5898 symbol mangling style your C++ compiler uses.
5900 Calling of methods and virtual functions has been improved as well.
5904 The crash that occured when debugging Sun Ansi-C compiled binaries is
5905 fixed. This was due to mishandling of the extra N_SO stabs output
5908 We also finally got Ultrix 4.2 running in house, and fixed core file
5909 support, with help from a dozen people on the net.
5911 John M. Farrell discovered that the reason that single-stepping was so
5912 slow on all of the Mips based platforms (primarily SGI and DEC) was
5913 that we were trying to demangle and lookup a symbol used for internal
5914 purposes on every instruction that was being stepped through. Changing
5915 the name of that symbol so that it couldn't be mistaken for a C++
5916 mangled symbol sped things up a great deal.
5918 Rich Pixley sped up symbol lookups in general by getting much smarter
5919 about when C++ symbol mangling is necessary. This should make symbol
5920 completion (TAB on the command line) much faster. It's not as fast as
5921 we'd like, but it's significantly faster than gdb-4.6.
5925 A new user controllable variable 'call_scratch_address' can
5926 specify the location of a scratch area to be used when GDB
5927 calls a function in the target. This is necessary because the
5928 usual method of putting the scratch area on the stack does not work
5929 in systems that have separate instruction and data spaces.
5931 We integrated changes to support the 29k UDI (Universal Debugger
5932 Interface), but discovered at the last minute that we didn't have all
5933 of the appropriate copyright paperwork. We are working with AMD to
5934 resolve this, and hope to have it available soon.
5938 We have sped up the remote serial line protocol, especially for targets
5939 with lots of registers. It now supports a new `expedited status' ('T')
5940 message which can be used in place of the existing 'S' status message.
5941 This allows the remote stub to send only the registers that GDB
5942 needs to make a quick decision about single-stepping or conditional
5943 breakpoints, eliminating the need to fetch the entire register set for
5944 each instruction being stepped through.
5946 The GDB remote serial protocol now implements a write-through cache for
5947 registers, only re-reading the registers if the target has run.
5949 There is also a new remote serial stub for SPARC processors. You can
5950 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5951 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5952 processor with a serial port.
5956 Configure.in files have become much easier to read and modify. A new
5957 `table driven' format makes it more obvious what configurations are
5958 supported, and what files each one uses.
5962 There is a new opcodes library which will eventually contain all of the
5963 disassembly routines and opcode tables. At present, it only contains
5964 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5965 disassembler (binutils/objdump) to share these routines.
5967 The libiberty library is now copylefted under the GNU Library General
5968 Public License. This allows more liberal use, and was done so libg++
5969 can use it. This makes no difference to GDB, since the Library License
5970 grants all the rights from the General Public License.
5974 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5975 reference to the stabs symbol info used by the debugger. It is (as far
5976 as we know) the only published document on this fascinating topic. We
5977 encourage you to read it, compare it to the stabs information on your
5978 system, and send improvements on the document in general (to
5979 bug-gdb@prep.ai.mit.edu).
5981 And, of course, many bugs have been fixed.
5984 *** Changes in GDB-4.6:
5986 * Better support for C++ function names
5988 GDB now accepts as input the "demangled form" of C++ overloaded function
5989 names and member function names, and can do command completion on such names
5990 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5991 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5992 Make use of command completion, it is your friend.
5994 GDB also now accepts a variety of C++ mangled symbol formats. They are
5995 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5996 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5997 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5998 for the list of formats.
6000 * G++ symbol mangling problem
6002 Recent versions of gcc have a bug in how they emit debugging information for
6003 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6004 directory) can be applied to gcc to fix the problem. Alternatively, if you
6005 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6006 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6007 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6010 * New 'maintenance' command
6012 All of the commands related to hacking GDB internals have been moved out of
6013 the main command set, and now live behind the 'maintenance' command. This
6014 can also be abbreviated as 'mt'. The following changes were made:
6016 dump-me -> maintenance dump-me
6017 info all-breakpoints -> maintenance info breakpoints
6018 printmsyms -> maintenance print msyms
6019 printobjfiles -> maintenance print objfiles
6020 printpsyms -> maintenance print psymbols
6021 printsyms -> maintenance print symbols
6023 The following commands are new:
6025 maintenance demangle Call internal GDB demangler routine to
6026 demangle a C++ link name and prints the result.
6027 maintenance print type Print a type chain for a given symbol
6029 * Change to .gdbinit file processing
6031 We now read the $HOME/.gdbinit file before processing the argv arguments
6032 (e.g. reading symbol files or core files). This allows global parameters to
6033 be set, which will apply during the symbol reading. The ./.gdbinit is still
6034 read after argv processing.
6036 * New hosts supported
6038 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6040 GNU/Linux support i386-unknown-linux or linux
6042 We are also including code to support the HP/PA running BSD and HPUX. This
6043 is almost guaranteed not to work, as we didn't have time to test or build it
6044 for this release. We are including it so that the more adventurous (or
6045 masochistic) of you can play with it. We also had major problems with the
6046 fact that the compiler that we got from HP doesn't support the -g option.
6049 * New targets supported
6051 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6053 * More smarts about finding #include files
6055 GDB now remembers the compilation directory for all include files, and for
6056 all files from which C is generated (like yacc and lex sources). This
6057 greatly improves GDB's ability to find yacc/lex sources, and include files,
6058 especially if you are debugging your program from a directory different from
6059 the one that contains your sources.
6061 We also fixed a bug which caused difficulty with listing and setting
6062 breakpoints in include files which contain C code. (In the past, you had to
6063 try twice in order to list an include file that you hadn't looked at before.)
6065 * Interesting infernals change
6067 GDB now deals with arbitrary numbers of sections, where the symbols for each
6068 section must be relocated relative to that section's landing place in the
6069 target's address space. This work was needed to support ELF with embedded
6070 stabs used by Solaris-2.0.
6072 * Bug fixes (of course!)
6074 There have been loads of fixes for the following things:
6075 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6076 i960, stabs, DOS(GO32), procfs, etc...
6078 See the ChangeLog for details.
6080 *** Changes in GDB-4.5:
6082 * New machines supported (host and target)
6084 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6086 SGI Irix-4.x mips-sgi-irix4 or iris4
6088 * New malloc package
6090 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6091 Mmalloc is capable of handling mutiple heaps of memory. It is also
6092 capable of saving a heap to a file, and then mapping it back in later.
6093 This can be used to greatly speedup the startup of GDB by using a
6094 pre-parsed symbol table which lives in a mmalloc managed heap. For
6095 more details, please read mmalloc/mmalloc.texi.
6099 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6100 'help info proc' for details.
6102 * MIPS ecoff symbol table format
6104 The code that reads MIPS symbol table format is now supported on all hosts.
6105 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6108 * File name changes for MS-DOS
6110 Many files in the config directories have been renamed to make it easier to
6111 support GDB on MS-DOSe systems (which have very restrictive file name
6112 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6113 environment) is close to working but has some remaining problems. Note
6114 that debugging of DOS programs is not supported, due to limitations
6115 in the ``operating system'', but it can be used to host cross-debugging.
6117 * Cross byte order fixes
6119 Many fixes have been made to support cross debugging of Sparc and MIPS
6120 targets from hosts whose byte order differs.
6122 * New -mapped and -readnow options
6124 If memory-mapped files are available on your system through the 'mmap'
6125 system call, you can use the -mapped option on the `file' or
6126 `symbol-file' commands to cause GDB to write the symbols from your
6127 program into a reusable file. If the program you are debugging is
6128 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6129 Future GDB debugging sessions will notice the presence of this file,
6130 and will quickly map in symbol information from it, rather than reading
6131 the symbol table from the executable program. Using the '-mapped'
6132 option in a GDB `file' or `symbol-file' command has the same effect as
6133 starting GDB with the '-mapped' command-line option.
6135 You can cause GDB to read the entire symbol table immediately by using
6136 the '-readnow' option with any of the commands that load symbol table
6137 information (or on the GDB command line). This makes the command
6138 slower, but makes future operations faster.
6140 The -mapped and -readnow options are typically combined in order to
6141 build a `fred.syms' file that contains complete symbol information.
6142 A simple GDB invocation to do nothing but build a `.syms' file for future
6145 gdb -batch -nx -mapped -readnow programname
6147 The `.syms' file is specific to the host machine on which GDB is run.
6148 It holds an exact image of GDB's internal symbol table. It cannot be
6149 shared across multiple host platforms.
6151 * longjmp() handling
6153 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6154 siglongjmp() without losing control. This feature has not yet been ported to
6155 all systems. It currently works on many 386 platforms, all MIPS-based
6156 platforms (SGI, DECstation, etc), and Sun3/4.
6160 Preliminary work has been put in to support the new Solaris OS from Sun. At
6161 this time, it can control and debug processes, but it is not capable of
6166 As always, many many bug fixes. The major areas were with g++, and mipsread.
6167 People using the MIPS-based platforms should experience fewer mysterious
6168 crashes and trashed symbol tables.
6170 *** Changes in GDB-4.4:
6172 * New machines supported (host and target)
6174 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6176 BSD Reno on Vax vax-dec-bsd
6177 Ultrix on Vax vax-dec-ultrix
6179 * New machines supported (target)
6181 AMD 29000 embedded, using EBMON a29k-none-none
6185 GDB continues to improve its handling of C++. `References' work better.
6186 The demangler has also been improved, and now deals with symbols mangled as
6187 per the Annotated C++ Reference Guide.
6189 GDB also now handles `stabs' symbol information embedded in MIPS
6190 `ecoff' symbol tables. Since the ecoff format was not easily
6191 extensible to handle new languages such as C++, this appeared to be a
6192 good way to put C++ debugging info into MIPS binaries. This option
6193 will be supported in the GNU C compiler, version 2, when it is
6196 * New features for SVR4
6198 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6199 shared libraries. Debugging dynamically linked programs should present
6200 only minor differences from debugging statically linked programs.
6202 The `info proc' command will print out information about any process
6203 on an SVR4 system (including the one you are debugging). At the moment,
6204 it prints the address mappings of the process.
6206 If you bring up GDB on another SVR4 system, please send mail to
6207 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6209 * Better dynamic linking support in SunOS
6211 Reading symbols from shared libraries which contain debugging symbols
6212 now works properly. However, there remain issues such as automatic
6213 skipping of `transfer vector' code during function calls, which
6214 make it harder to debug code in a shared library, than to debug the
6215 same code linked statically.
6219 GDB is now using the latest `getopt' routines from the FSF. This
6220 version accepts the -- prefix for options with long names. GDB will
6221 continue to accept the old forms (-option and +option) as well.
6222 Various single letter abbreviations for options have been explicity
6223 added to the option table so that they won't get overshadowed in the
6224 future by other options that begin with the same letter.
6228 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6229 Many assorted bugs have been handled. Many more remain to be handled.
6230 See the various ChangeLog files (primarily in gdb and bfd) for details.
6233 *** Changes in GDB-4.3:
6235 * New machines supported (host and target)
6237 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6238 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6239 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6241 * Almost SCO Unix support
6243 We had hoped to support:
6244 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6245 (except for core file support), but we discovered very late in the release
6246 that it has problems with process groups that render gdb unusable. Sorry
6247 about that. I encourage people to fix it and post the fixes.
6249 * Preliminary ELF and DWARF support
6251 GDB can read ELF object files on System V Release 4, and can handle
6252 debugging records for C, in DWARF format, in ELF files. This support
6253 is preliminary. If you bring up GDB on another SVR4 system, please
6254 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6259 GDB now uses the latest `readline' library. One user-visible change
6260 is that two tabs will list possible command completions, which previously
6261 required typing M-? (meta-question mark, or ESC ?).
6265 The `stepi' bug that many of you noticed has been squashed.
6266 Many bugs in C++ have been handled. Many more remain to be handled.
6267 See the various ChangeLog files (primarily in gdb and bfd) for details.
6269 * State of the MIPS world (in case you wondered):
6271 GDB can understand the symbol tables emitted by the compilers
6272 supplied by most vendors of MIPS-based machines, including DEC. These
6273 symbol tables are in a format that essentially nobody else uses.
6275 Some versions of gcc come with an assembler post-processor called
6276 mips-tfile. This program is required if you want to do source-level
6277 debugging of gcc-compiled programs. I believe FSF does not ship
6278 mips-tfile with gcc version 1, but it will eventually come with gcc
6281 Debugging of g++ output remains a problem. g++ version 1.xx does not
6282 really support it at all. (If you're lucky, you should be able to get
6283 line numbers and stack traces to work, but no parameters or local
6284 variables.) With some work it should be possible to improve the
6287 When gcc version 2 is released, you will have somewhat better luck.
6288 However, even then you will get confusing results for inheritance and
6291 We will eventually provide full debugging of g++ output on
6292 DECstations. This will probably involve some kind of stabs-in-ecoff
6293 encapulation, but the details have not been worked out yet.
6296 *** Changes in GDB-4.2:
6298 * Improved configuration
6300 Only one copy of `configure' exists now, and it is not self-modifying.
6301 Porting BFD is simpler.
6305 The `step' and `next' commands now only stop at the first instruction
6306 of a source line. This prevents the multiple stops that used to occur
6307 in switch statements, for-loops, etc. `Step' continues to stop if a
6308 function that has debugging information is called within the line.
6312 Lots of small bugs fixed. More remain.
6314 * New host supported (not target)
6316 Intel 386 PC clone running Mach i386-none-mach
6319 *** Changes in GDB-4.1:
6321 * Multiple source language support
6323 GDB now has internal scaffolding to handle several source languages.
6324 It determines the type of each source file from its filename extension,
6325 and will switch expression parsing and number formatting to match the
6326 language of the function in the currently selected stack frame.
6327 You can also specifically set the language to be used, with
6328 `set language c' or `set language modula-2'.
6332 GDB now has preliminary support for the GNU Modula-2 compiler,
6333 currently under development at the State University of New York at
6334 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6335 continue through the fall of 1991 and into 1992.
6337 Other Modula-2 compilers are currently not supported, and attempting to
6338 debug programs compiled with them will likely result in an error as the
6339 symbol table is read. Feel free to work on it, though!
6341 There are hooks in GDB for strict type checking and range checking,
6342 in the `Modula-2 philosophy', but they do not currently work.
6346 GDB can now write to executable and core files (e.g. patch
6347 a variable's value). You must turn this switch on, specify
6348 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6349 by assigning a new value to a variable. Modifications take
6352 * Automatic SunOS shared library reading
6354 When you run your program, GDB automatically determines where its
6355 shared libraries (if any) have been loaded, and reads their symbols.
6356 The `share' command is no longer needed. This also works when
6357 examining core files.
6361 You can specify the number of lines that the `list' command shows.
6364 * New machines supported (host and target)
6366 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6367 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6368 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6370 * New hosts supported (not targets)
6372 IBM RT/PC: romp-ibm-aix or rtpc
6374 * New targets supported (not hosts)
6376 AMD 29000 embedded with COFF a29k-none-coff
6377 AMD 29000 embedded with a.out a29k-none-aout
6378 Ultracomputer remote kernel debug a29k-nyu-kern
6380 * New remote interfaces
6386 *** Changes in GDB-4.0:
6390 Wide output is wrapped at good places to make the output more readable.
6392 Gdb now supports cross-debugging from a host machine of one type to a
6393 target machine of another type. Communication with the target system
6394 is over serial lines. The ``target'' command handles connecting to the
6395 remote system; the ``load'' command will download a program into the
6396 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6397 also supports debugging of realtime processes running under VxWorks,
6398 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6399 stub on the target system.
6401 New CPUs supported include the AMD 29000 and Intel 960.
6403 GDB now reads object files and symbol tables via a ``binary file''
6404 library, which allows a single copy of GDB to debug programs of multiple
6405 object file types such as a.out and coff.
6407 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6408 refcard.dvi and refcard.ps are available to format it).
6411 * Control-Variable user interface simplified
6413 All variables that control the operation of the debugger can be set
6414 by the ``set'' command, and displayed by the ``show'' command.
6416 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6417 ``Show prompt'' produces the response:
6418 Gdb's prompt is new-gdb=>.
6420 What follows are the NEW set commands. The command ``help set'' will
6421 print a complete list of old and new set commands. ``help set FOO''
6422 will give a longer description of the variable FOO. ``show'' will show
6423 all of the variable descriptions and their current settings.
6425 confirm on/off: Enables warning questions for operations that are
6426 hard to recover from, e.g. rerunning the program while
6427 it is already running. Default is ON.
6429 editing on/off: Enables EMACS style command line editing
6430 of input. Previous lines can be recalled with
6431 control-P, the current line can be edited with control-B,
6432 you can search for commands with control-R, etc.
6435 history filename NAME: NAME is where the gdb command history
6436 will be stored. The default is .gdb_history,
6437 or the value of the environment variable
6440 history size N: The size, in commands, of the command history. The
6441 default is 256, or the value of the environment variable
6444 history save on/off: If this value is set to ON, the history file will
6445 be saved after exiting gdb. If set to OFF, the
6446 file will not be saved. The default is OFF.
6448 history expansion on/off: If this value is set to ON, then csh-like
6449 history expansion will be performed on
6450 command line input. The default is OFF.
6452 radix N: Sets the default radix for input and output. It can be set
6453 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6454 in the current radix, so "set radix 10" is always a no-op.
6456 height N: This integer value is the number of lines on a page. Default
6457 is 24, the current `stty rows'' setting, or the ``li#''
6458 setting from the termcap entry matching the environment
6461 width N: This integer value is the number of characters on a line.
6462 Default is 80, the current `stty cols'' setting, or the ``co#''
6463 setting from the termcap entry matching the environment
6466 Note: ``set screensize'' is obsolete. Use ``set height'' and
6467 ``set width'' instead.
6469 print address on/off: Print memory addresses in various command displays,
6470 such as stack traces and structure values. Gdb looks
6471 more ``symbolic'' if you turn this off; it looks more
6472 ``machine level'' with it on. Default is ON.
6474 print array on/off: Prettyprint arrays. New convenient format! Default
6477 print demangle on/off: Print C++ symbols in "source" form if on,
6480 print asm-demangle on/off: Same, for assembler level printouts
6483 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6486 * Support for Epoch Environment.
6488 The epoch environment is a version of Emacs v18 with windowing. One
6489 new command, ``inspect'', is identical to ``print'', except that if you
6490 are running in the epoch environment, the value is printed in its own
6494 * Support for Shared Libraries
6496 GDB can now debug programs and core files that use SunOS shared libraries.
6497 Symbols from a shared library cannot be referenced
6498 before the shared library has been linked with the program (this
6499 happens after you type ``run'' and before the function main() is entered).
6500 At any time after this linking (including when examining core files
6501 from dynamically linked programs), gdb reads the symbols from each
6502 shared library when you type the ``sharedlibrary'' command.
6503 It can be abbreviated ``share''.
6505 sharedlibrary REGEXP: Load shared object library symbols for files
6506 matching a unix regular expression. No argument
6507 indicates to load symbols for all shared libraries.
6509 info sharedlibrary: Status of loaded shared libraries.
6514 A watchpoint stops execution of a program whenever the value of an
6515 expression changes. Checking for this slows down execution
6516 tremendously whenever you are in the scope of the expression, but is
6517 quite useful for catching tough ``bit-spreader'' or pointer misuse
6518 problems. Some machines such as the 386 have hardware for doing this
6519 more quickly, and future versions of gdb will use this hardware.
6521 watch EXP: Set a watchpoint (breakpoint) for an expression.
6523 info watchpoints: Information about your watchpoints.
6525 delete N: Deletes watchpoint number N (same as breakpoints).
6526 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6527 enable N: Re-enables watchpoint number N (same as breakpoints).
6530 * C++ multiple inheritance
6532 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6535 * C++ exception handling
6537 Gdb now supports limited C++ exception handling. Besides the existing
6538 ability to breakpoint on an exception handler, gdb can breakpoint on
6539 the raising of an exception (before the stack is peeled back to the
6542 catch FOO: If there is a FOO exception handler in the dynamic scope,
6543 set a breakpoint to catch exceptions which may be raised there.
6544 Multiple exceptions (``catch foo bar baz'') may be caught.
6546 info catch: Lists all exceptions which may be caught in the
6547 current stack frame.
6550 * Minor command changes
6552 The command ``call func (arg, arg, ...)'' now acts like the print
6553 command, except it does not print or save a value if the function's result
6554 is void. This is similar to dbx usage.
6556 The ``up'' and ``down'' commands now always print the frame they end up
6557 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6558 frames without printing.
6560 * New directory command
6562 'dir' now adds directories to the FRONT of the source search path.
6563 The path starts off empty. Source files that contain debug information
6564 about the directory in which they were compiled can be found even
6565 with an empty path; Sun CC and GCC include this information. If GDB can't
6566 find your source file in the current directory, type "dir .".
6568 * Configuring GDB for compilation
6570 For normal use, type ``./configure host''. See README or gdb.texinfo
6573 GDB now handles cross debugging. If you are remotely debugging between
6574 two different machines, type ``./configure host -target=targ''.
6575 Host is the machine where GDB will run; targ is the machine
6576 where the program that you are debugging will run.