1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.12
6 *** Changes in GDB 7.12
8 * GDB and GDBserver now build with a C++ compiler by default.
10 The --enable-build-with-cxx configure option is now enabled by
11 default. One must now explicitly configure with
12 --disable-build-with-cxx in order to build with a C compiler. This
13 option will be removed in a future release.
15 * GDBserver now supports recording btrace without maintaining an active
18 * GDB now supports a negative repeat count in the 'x' command to examine
19 memory backward from the given address. For example:
22 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
23 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
24 (gdb) x/-5i 0x0000000000400580
25 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
26 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
27 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
28 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
29 0x40057b <main(int, char**)+25>:
30 callq 0x400536 <Func1(int, char const*)>
32 * Fortran: Support structures with fields of dynamic types and
33 arrays of dynamic types.
35 * GDB now supports multibit bitfields and enums in target register
38 * New Python-based convenience function $_as_string(val), which returns
39 the textual representation of a value. This function is especially
40 useful to obtain the text label of an enum value.
42 * Intel MPX bound violation handling.
44 Segmentation faults caused by a Intel MPX boundary violation
45 now display the kind of violation (upper or lower), the memory
46 address accessed and the memory bounds, along with the usual
47 signal received and code location.
51 Program received signal SIGSEGV, Segmentation fault
52 Upper bound violation while accessing address 0x7fffffffc3b3
53 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
54 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
56 * Rust language support.
57 GDB now supports debugging programs written in the Rust programming
58 language. See https://www.rust-lang.org/ for more information about
61 * Support for running interpreters on specified input/output devices
63 GDB now supports a new mechanism that allows frontends to provide
64 fully featured GDB console views, as a better alternative to
65 building such views on top of the "-interpreter-exec console"
66 command. See the new "new-ui" command below. With that command,
67 frontends can now start GDB in the traditional command-line mode
68 running in an embedded terminal emulator widget, and create a
69 separate MI interpreter running on a specified i/o device. In this
70 way, GDB handles line editing, history, tab completion, etc. in the
71 console all by itself, and the GUI uses the separate MI interpreter
72 for its own control and synchronization, invisible to the command
75 * The "catch syscall" command catches groups of related syscalls.
77 The "catch syscall" command now supports catching a group of related
78 syscalls using the 'group:' or 'g:' prefix.
83 skip -gfile file-glob-pattern
84 skip -function function
85 skip -rfunction regular-expression
86 A generalized form of the skip command, with new support for
87 glob-style file names and regular expressions for function names.
88 Additionally, a file spec and a function spec may now be combined.
90 maint info line-table REGEXP
91 Display the contents of GDB's internal line table data struture.
94 Run any GDB unit tests that were compiled in.
97 Start a new user interface instance running INTERP as interpreter,
98 using the TTY file for input/output.
102 ** gdb.Breakpoint objects have a new attribute "pending", which
103 indicates whether the breakpoint is pending.
104 ** Three new breakpoint-related events have been added:
105 gdb.breakpoint_created, gdb.breakpoint_modified, and
106 gdb.breakpoint_deleted.
109 Signal ("set") the given MS-Windows event object. This is used in
110 conjunction with the Windows JIT debugging (AeDebug) support, where
111 the OS suspends a crashing process until a debugger can attach to
112 it. Resuming the crashing process, in order to debug it, is done by
115 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
116 was added in GDBserver, including JIT compiling fast tracepoint's
117 conditional expression bytecode into native code.
119 * Support for various remote target protocols and ROM monitors has
122 target m32rsdi Remote M32R debugging over SDI
123 target mips MIPS remote debugging protocol
124 target pmon PMON ROM monitor
125 target ddb NEC's DDB variant of PMON for Vr4300
126 target rockhopper NEC RockHopper variant of PMON
127 target lsi LSI variant of PMO
129 * Support for tracepoints and fast tracepoints on powerpc-linux,
130 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
131 including JIT compiling fast tracepoint's conditional expression
132 bytecode into native code.
134 * MI async record =record-started now includes the method and format used for
135 recording. For example:
137 =record-started,thread-group="i1",method="btrace",format="bts"
141 Andes NDS32 nds32*-*-elf
143 *** Changes in GDB 7.11
145 * GDB now supports debugging kernel-based threads on FreeBSD.
147 * Per-inferior thread numbers
149 Thread numbers are now per inferior instead of global. If you're
150 debugging multiple inferiors, GDB displays thread IDs using a
151 qualified INF_NUM.THR_NUM form. For example:
155 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
156 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
157 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
158 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
160 As consequence, thread numbers as visible in the $_thread
161 convenience variable and in Python's InferiorThread.num attribute
162 are no longer unique between inferiors.
164 GDB now maintains a second thread ID per thread, referred to as the
165 global thread ID, which is the new equivalent of thread numbers in
166 previous releases. See also $_gthread below.
168 For backwards compatibility, MI's thread IDs always refer to global
171 * Commands that accept thread IDs now accept the qualified
172 INF_NUM.THR_NUM form as well. For example:
175 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
178 * In commands that accept a list of thread IDs, you can now refer to
179 all threads of an inferior using a star wildcard. GDB accepts
180 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
181 refer to all threads of the current inferior. For example, "info
184 * You can use "info threads -gid" to display the global thread ID of
187 * The new convenience variable $_gthread holds the global number of
190 * The new convenience variable $_inferior holds the number of the
193 * GDB now displays the ID and name of the thread that hit a breakpoint
194 or received a signal, if your program is multi-threaded. For
197 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
198 Thread 1 "main" received signal SIGINT, Interrupt.
200 * Record btrace now supports non-stop mode.
202 * Support for tracepoints on aarch64-linux was added in GDBserver.
204 * The 'record instruction-history' command now indicates speculative execution
205 when using the Intel Processor Trace recording format.
207 * GDB now allows users to specify explicit locations, bypassing
208 the linespec parser. This feature is also available to GDB/MI
211 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
212 GDB now is able to debug both AArch64 applications and ARM applications
215 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
216 including JIT compiling fast tracepoint's conditional expression bytecode
219 * GDB now supports displaced stepping on AArch64 GNU/Linux.
221 * "info threads", "info inferiors", "info display", "info checkpoints"
222 and "maint info program-spaces" now list the corresponding items in
223 ascending ID order, for consistency with all other "info" commands.
225 * In Ada, the overloads selection menu has been enhanced to display the
226 parameter types and the return types for the matching overloaded subprograms.
230 maint set target-non-stop (on|off|auto)
231 maint show target-non-stop
232 Control whether GDB targets always operate in non-stop mode even if
233 "set non-stop" is "off". The default is "auto", meaning non-stop
234 mode is enabled if supported by the target.
236 maint set bfd-sharing
237 maint show bfd-sharing
238 Control the reuse of bfd objects.
242 Control display of debugging info regarding bfd caching.
246 Control display of debugging info regarding FreeBSD threads.
248 set remote multiprocess-extensions-packet
249 show remote multiprocess-extensions-packet
250 Set/show the use of the remote protocol multiprocess extensions.
252 set remote thread-events
253 show remote thread-events
254 Set/show the use of thread create/exit events.
256 set ada print-signatures on|off
257 show ada print-signatures"
258 Control whether parameter types and return types are displayed in overloads
259 selection menus. It is activaled (@code{on}) by default.
263 Controls the maximum size of memory, in bytes, that GDB will
264 allocate for value contents. Prevents incorrect programs from
265 causing GDB to allocate overly large buffers. Default is 64k.
267 * The "disassemble" command accepts a new modifier: /s.
268 It prints mixed source+disassembly like /m with two differences:
269 - disassembled instructions are now printed in program order, and
270 - and source for all relevant files is now printed.
271 The "/m" option is now considered deprecated: its "source-centric"
272 output hasn't proved useful in practice.
274 * The "record instruction-history" command accepts a new modifier: /s.
275 It behaves exactly like /m and prints mixed source+disassembly.
277 * The "set scheduler-locking" command supports a new mode "replay".
278 It behaves like "off" in record mode and like "on" in replay mode.
280 * Support for various ROM monitors has been removed:
282 target dbug dBUG ROM monitor for Motorola ColdFire
283 target picobug Motorola picobug monitor
284 target dink32 DINK32 ROM monitor for PowerPC
285 target m32r Renesas M32R/D ROM monitor
286 target mon2000 mon2000 ROM monitor
287 target ppcbug PPCBUG ROM monitor for PowerPC
289 * Support for reading/writing memory and extracting values on architectures
290 whose memory is addressable in units of any integral multiple of 8 bits.
295 Indicates that an exec system call was executed.
297 exec-events feature in qSupported
298 The qSupported packet allows GDB to request support for exec
299 events using the new 'gdbfeature' exec-event, and the qSupported
300 response can contain the corresponding 'stubfeature'. Set and
301 show commands can be used to display whether these features are enabled.
304 Equivalent to interrupting with the ^C character, but works in
307 thread created stop reason (T05 create:...)
308 Indicates that the thread was just created and is stopped at entry.
310 thread exit stop reply (w exitcode;tid)
311 Indicates that the thread has terminated.
314 Enables/disables thread create and exit event reporting. For
315 example, this is used in non-stop mode when GDB stops a set of
316 threads and synchronously waits for the their corresponding stop
317 replies. Without exit events, if one of the threads exits, GDB
318 would hang forever not knowing that it should no longer expect a
319 stop for that same thread.
322 Indicates that there are no resumed threads left in the target (all
323 threads are stopped). The remote stub reports support for this stop
324 reply to GDB's qSupported query.
327 Enables/disables catching syscalls from the inferior process.
328 The remote stub reports support for this packet to GDB's qSupported query.
330 syscall_entry stop reason
331 Indicates that a syscall was just called.
333 syscall_return stop reason
334 Indicates that a syscall just returned.
336 * Extended-remote exec events
338 ** GDB now has support for exec events on extended-remote Linux targets.
339 For such targets with Linux kernels 2.5.46 and later, this enables
340 follow-exec-mode and exec catchpoints.
342 set remote exec-event-feature-packet
343 show remote exec-event-feature-packet
344 Set/show the use of the remote exec event feature.
346 * Thread names in remote protocol
348 The reply to qXfer:threads:read may now include a name attribute for each
351 * Target remote mode fork and exec events
353 ** GDB now has support for fork and exec events on target remote mode
354 Linux targets. For such targets with Linux kernels 2.5.46 and later,
355 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
356 fork and exec catchpoints.
358 * Remote syscall events
360 ** GDB now has support for catch syscall on remote Linux targets,
361 currently enabled on x86/x86_64 architectures.
363 set remote catch-syscall-packet
364 show remote catch-syscall-packet
365 Set/show the use of the remote catch syscall feature.
369 ** The -var-set-format command now accepts the zero-hexadecimal
370 format. It outputs data in hexadecimal format with zero-padding on the
375 ** gdb.InferiorThread objects have a new attribute "global_num",
376 which refers to the thread's global thread ID. The existing
377 "num" attribute now refers to the thread's per-inferior number.
378 See "Per-inferior thread numbers" above.
379 ** gdb.InferiorThread objects have a new attribute "inferior", which
380 is the Inferior object the thread belongs to.
382 *** Changes in GDB 7.10
384 * Support for process record-replay and reverse debugging on aarch64*-linux*
385 targets has been added. GDB now supports recording of A64 instruction set
386 including advance SIMD instructions.
388 * Support for Sun's version of the "stabs" debug file format has been removed.
390 * GDB now honors the content of the file /proc/PID/coredump_filter
391 (PID is the process ID) on GNU/Linux systems. This file can be used
392 to specify the types of memory mappings that will be included in a
393 corefile. For more information, please refer to the manual page of
394 "core(5)". GDB also has a new command: "set use-coredump-filter
395 on|off". It allows to set whether GDB will read the content of the
396 /proc/PID/coredump_filter file when generating a corefile.
398 * The "info os" command on GNU/Linux can now display information on
400 "info os cpus" Listing of all cpus/cores on the system
402 * GDB has two new commands: "set serial parity odd|even|none" and
403 "show serial parity". These allows to set or show parity for the
406 * The "info source" command now displays the producer string if it was
407 present in the debug info. This typically includes the compiler version
408 and may include things like its command line arguments.
410 * The "info dll", an alias of the "info sharedlibrary" command,
411 is now available on all platforms.
413 * Directory names supplied to the "set sysroot" commands may be
414 prefixed with "target:" to tell GDB to access shared libraries from
415 the target system, be it local or remote. This replaces the prefix
416 "remote:". The default sysroot has been changed from "" to
417 "target:". "remote:" is automatically converted to "target:" for
418 backward compatibility.
420 * The system root specified by "set sysroot" will be prepended to the
421 filename of the main executable (if reported to GDB as absolute by
422 the operating system) when starting processes remotely, and when
423 attaching to already-running local or remote processes.
425 * GDB now supports automatic location and retrieval of executable
426 files from remote targets. Remote debugging can now be initiated
427 using only a "target remote" or "target extended-remote" command
428 (no "set sysroot" or "file" commands are required). See "New remote
431 * The "dump" command now supports verilog hex format.
433 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
435 * On GNU/Linux, GDB and gdbserver are now able to access executable
436 and shared library files without a "set sysroot" command when
437 attaching to processes running in different mount namespaces from
438 the debugger. This makes it possible to attach to processes in
439 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
440 See "New remote packets" below.
442 * The "tui reg" command now provides completion for all of the
443 available register groups, including target specific groups.
445 * The HISTSIZE environment variable is no longer read when determining
446 the size of GDB's command history. GDB now instead reads the dedicated
447 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
448 disables truncation of command history. Non-numeric values of GDBHISTSIZE
453 ** Memory ports can now be unbuffered.
457 ** gdb.Objfile objects have a new attribute "username",
458 which is the name of the objfile as specified by the user,
459 without, for example, resolving symlinks.
460 ** You can now write frame unwinders in Python.
461 ** gdb.Type objects have a new method "optimized_out",
462 returning optimized out gdb.Value instance of this type.
463 ** gdb.Value objects have new methods "reference_value" and
464 "const_value" which return a reference to the value and a
465 "const" version of the value respectively.
469 maint print symbol-cache
470 Print the contents of the symbol cache.
472 maint print symbol-cache-statistics
473 Print statistics of symbol cache usage.
475 maint flush-symbol-cache
476 Flush the contents of the symbol cache.
480 Start branch trace recording using Branch Trace Store (BTS) format.
483 Evaluate expression by using the compiler and print result.
487 Explicit commands for enabling and disabling tui mode.
490 set mpx bound on i386 and amd64
491 Support for bound table investigation on Intel MPX enabled applications.
495 Start branch trace recording using Intel Processor Trace format.
498 Print information about branch tracing internals.
500 maint btrace packet-history
501 Print the raw branch tracing data.
503 maint btrace clear-packet-history
504 Discard the stored raw branch tracing data.
507 Discard all branch tracing data. It will be fetched and processed
508 anew by the next "record" command.
513 Renamed from "set debug dwarf2-die".
515 Renamed from "show debug dwarf2-die".
518 Renamed from "set debug dwarf2-read".
519 show debug dwarf-read
520 Renamed from "show debug dwarf2-read".
522 maint set dwarf always-disassemble
523 Renamed from "maint set dwarf2 always-disassemble".
524 maint show dwarf always-disassemble
525 Renamed from "maint show dwarf2 always-disassemble".
527 maint set dwarf max-cache-age
528 Renamed from "maint set dwarf2 max-cache-age".
529 maint show dwarf max-cache-age
530 Renamed from "maint show dwarf2 max-cache-age".
533 show debug dwarf-line
534 Control display of debugging info regarding DWARF line processing.
538 Set the maximum number of candidates to be considered during
539 completion. The default value is 200. This limit allows GDB
540 to avoid generating large completion lists, the computation of
541 which can cause the debugger to become temporarily unresponsive.
543 set history remove-duplicates
544 show history remove-duplicates
545 Control the removal of duplicate history entries.
547 maint set symbol-cache-size
548 maint show symbol-cache-size
549 Control the size of the symbol cache.
551 set|show record btrace bts buffer-size
552 Set and show the size of the ring buffer used for branch tracing in
554 The obtained size may differ from the requested size. Use "info
555 record" to see the obtained buffer size.
557 set debug linux-namespaces
558 show debug linux-namespaces
559 Control display of debugging info regarding Linux namespaces.
561 set|show record btrace pt buffer-size
562 Set and show the size of the ring buffer used for branch tracing in
563 Intel Processor Trace format.
564 The obtained size may differ from the requested size. Use "info
565 record" to see the obtained buffer size.
567 maint set|show btrace pt skip-pad
568 Set and show whether PAD packets are skipped when computing the
571 * The command 'thread apply all' can now support new option '-ascending'
572 to call its specified command for all threads in ascending order.
574 * Python/Guile scripting
576 ** GDB now supports auto-loading of Python/Guile scripts contained in the
577 special section named `.debug_gdb_scripts'.
581 qXfer:btrace-conf:read
582 Return the branch trace configuration for the current thread.
584 Qbtrace-conf:bts:size
585 Set the requested ring buffer size for branch tracing in BTS format.
588 Enable Intel Procesor Trace-based branch tracing for the current
589 process. The remote stub reports support for this packet to GDB's
593 Set the requested ring buffer size for branch tracing in Intel Processor
597 Indicates a memory breakpoint instruction was executed, irrespective
598 of whether it was GDB that planted the breakpoint or the breakpoint
599 is hardcoded in the program. This is required for correct non-stop
603 Indicates the target stopped for a hardware breakpoint. This is
604 required for correct non-stop mode operation.
607 Return information about files on the remote system.
610 Return the full absolute name of the file that was executed to
611 create a process running on the remote system.
614 Select the filesystem on which vFile: operations with filename
615 arguments will operate. This is required for GDB to be able to
616 access files on remote targets where the remote stub does not
617 share a common filesystem with the inferior(s).
620 Indicates that a fork system call was executed.
623 Indicates that a vfork system call was executed.
625 vforkdone stop reason
626 Indicates that a vfork child of the specified process has executed
627 an exec or exit, allowing the vfork parent to resume execution.
629 fork-events and vfork-events features in qSupported
630 The qSupported packet allows GDB to request support for fork and
631 vfork events using new 'gdbfeatures' fork-events and vfork-events,
632 and the qSupported response can contain the corresponding
633 'stubfeatures'. Set and show commands can be used to display
634 whether these features are enabled.
636 * Extended-remote fork events
638 ** GDB now has support for fork events on extended-remote Linux
639 targets. For targets with Linux kernels 2.5.60 and later, this
640 enables follow-fork-mode and detach-on-fork for both fork and
641 vfork, as well as fork and vfork catchpoints.
643 * The info record command now shows the recording format and the
644 branch tracing configuration for the current thread when using
645 the btrace record target.
646 For the BTS format, it shows the ring buffer size.
648 * GDB now has support for DTrace USDT (Userland Static Defined
649 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
651 * GDB now supports access to vector registers on S/390 GNU/Linux
654 * Removed command line options
656 -xdb HP-UX XDB compatibility mode.
658 * Removed targets and native configurations
660 HP/PA running HP-UX hppa*-*-hpux*
661 Itanium running HP-UX ia64-*-hpux*
663 * New configure options
666 This configure option allows the user to build GDB with support for
667 Intel Processor Trace (default: auto). This requires libipt.
669 --with-libipt-prefix=PATH
670 Specify the path to the version of libipt that GDB should use.
671 $PATH/include should contain the intel-pt.h header and
672 $PATH/lib should contain the libipt.so library.
674 *** Changes in GDB 7.9.1
678 ** Xmethods can now specify a result type.
680 *** Changes in GDB 7.9
682 * GDB now supports hardware watchpoints on x86 GNU Hurd.
686 ** You can now access frame registers from Python scripts.
687 ** New attribute 'producer' for gdb.Symtab objects.
688 ** gdb.Objfile objects have a new attribute "progspace",
689 which is the gdb.Progspace object of the containing program space.
690 ** gdb.Objfile objects have a new attribute "owner".
691 ** gdb.Objfile objects have a new attribute "build_id",
692 which is the build ID generated when the file was built.
693 ** gdb.Objfile objects have a new method "add_separate_debug_file".
694 ** A new event "gdb.clear_objfiles" has been added, triggered when
695 selecting a new file to debug.
696 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
697 ** New function gdb.lookup_objfile.
699 New events which are triggered when GDB modifies the state of the
702 ** gdb.events.inferior_call_pre: Function call is about to be made.
703 ** gdb.events.inferior_call_post: Function call has just been made.
704 ** gdb.events.memory_changed: A memory location has been altered.
705 ** gdb.events.register_changed: A register has been altered.
707 * New Python-based convenience functions:
709 ** $_caller_is(name [, number_of_frames])
710 ** $_caller_matches(regexp [, number_of_frames])
711 ** $_any_caller_is(name [, number_of_frames])
712 ** $_any_caller_matches(regexp [, number_of_frames])
714 * GDB now supports the compilation and injection of source code into
715 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
716 to compile the source code to object code, and if successful, inject
717 and execute that code within the current context of the inferior.
718 Currently the C language is supported. The commands used to
719 interface with this new feature are:
721 compile code [-raw|-r] [--] [source code]
722 compile file [-raw|-r] filename
726 demangle [-l language] [--] name
727 Demangle "name" in the specified language, or the current language
728 if elided. This command is renamed from the "maint demangle" command.
729 The latter is kept as a no-op to avoid "maint demangle" being interpreted
730 as "maint demangler-warning".
732 queue-signal signal-name-or-number
733 Queue a signal to be delivered to the thread when it is resumed.
735 add-auto-load-scripts-directory directory
736 Add entries to the list of directories from which to load auto-loaded
739 maint print user-registers
740 List all currently available "user" registers.
742 compile code [-r|-raw] [--] [source code]
743 Compile, inject, and execute in the inferior the executable object
744 code produced by compiling the provided source code.
746 compile file [-r|-raw] filename
747 Compile and inject into the inferior the executable object code
748 produced by compiling the source code stored in the filename
751 * On resume, GDB now always passes the signal the program had stopped
752 for to the thread the signal was sent to, even if the user changed
753 threads before resuming. Previously GDB would often (but not
754 always) deliver the signal to the thread that happens to be current
757 * Conversely, the "signal" command now consistently delivers the
758 requested signal to the current thread. GDB now asks for
759 confirmation if the program had stopped for a signal and the user
760 switched threads meanwhile.
762 * "breakpoint always-inserted" modes "off" and "auto" merged.
764 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
765 won't remove breakpoints from the target until all threads stop,
766 even in non-stop mode. The "auto" mode has been removed, and "off"
767 is now the default mode.
771 set debug symbol-lookup
772 show debug symbol-lookup
773 Control display of debugging info regarding symbol lookup.
777 ** The -list-thread-groups command outputs an exit-code field for
778 inferiors that have exited.
782 MIPS SDE mips*-sde*-elf*
786 Support for these obsolete configurations has been removed.
788 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
789 SGI Irix-5.x mips-*-irix5*
790 SGI Irix-6.x mips-*-irix6*
791 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
792 VAX running Ultrix vax-*-ultrix*
794 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
795 and "assf"), have been removed. Use the "sharedlibrary" command, or
796 its alias "share", instead.
798 *** Changes in GDB 7.8
800 * New command line options
803 This is an alias for the --data-directory option.
805 * GDB supports printing and modifying of variable length automatic arrays
806 as specified in ISO C99.
808 * The ARM simulator now supports instruction level tracing
809 with or without disassembly.
813 GDB now has support for scripting using Guile. Whether this is
814 available is determined at configure time.
815 Guile version 2.0 or greater is required.
816 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
818 * New commands (for set/show, see "New options" below)
822 Invoke CODE by passing it to the Guile interpreter.
826 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
828 info auto-load guile-scripts [regexp]
829 Print the list of automatically loaded Guile scripts.
831 * The source command is now capable of sourcing Guile scripts.
832 This feature is dependent on the debugger being built with Guile support.
836 set print symbol-loading (off|brief|full)
837 show print symbol-loading
838 Control whether to print informational messages when loading symbol
839 information for a file. The default is "full", but when debugging
840 programs with large numbers of shared libraries the amount of output
843 set guile print-stack (none|message|full)
844 show guile print-stack
845 Show a stack trace when an error is encountered in a Guile script.
847 set auto-load guile-scripts (on|off)
848 show auto-load guile-scripts
849 Control auto-loading of Guile script files.
851 maint ada set ignore-descriptive-types (on|off)
852 maint ada show ignore-descriptive-types
853 Control whether the debugger should ignore descriptive types in Ada
854 programs. The default is not to ignore the descriptive types. See
855 the user manual for more details on descriptive types and the intended
856 usage of this option.
858 set auto-connect-native-target
860 Control whether GDB is allowed to automatically connect to the
861 native target for the run, attach, etc. commands when not connected
862 to any target yet. See also "target native" below.
864 set record btrace replay-memory-access (read-only|read-write)
865 show record btrace replay-memory-access
866 Control what memory accesses are allowed during replay.
868 maint set target-async (on|off)
869 maint show target-async
870 This controls whether GDB targets operate in synchronous or
871 asynchronous mode. Normally the default is asynchronous, if it is
872 available; but this can be changed to more easily debug problems
873 occurring only in synchronous mode.
875 set mi-async (on|off)
877 Control whether MI asynchronous mode is preferred. This supersedes
878 "set target-async" of previous GDB versions.
880 * "set target-async" is deprecated as a CLI option and is now an alias
881 for "set mi-async" (only puts MI into async mode).
883 * Background execution commands (e.g., "c&", "s&", etc.) are now
884 possible ``out of the box'' if the target supports them. Previously
885 the user would need to explicitly enable the possibility with the
886 "set target-async on" command.
888 * New features in the GDB remote stub, GDBserver
890 ** New option --debug-format=option1[,option2,...] allows one to add
891 additional text to each output. At present only timestamps
892 are supported: --debug-format=timestamps.
893 Timestamps can also be turned on with the
894 "monitor set debug-format timestamps" command from GDB.
896 * The 'record instruction-history' command now starts counting instructions
897 at one. This also affects the instruction ranges reported by the
898 'record function-call-history' command when given the /i modifier.
900 * The command 'record function-call-history' supports a new modifier '/c' to
901 indent the function names based on their call stack depth.
902 The fields for the '/i' and '/l' modifier have been reordered.
903 The source line range is now prefixed with 'at'.
904 The instruction range is now prefixed with 'inst'.
905 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
906 "record instruction-history" and "list" commands.
908 * The ranges given as arguments to the 'record function-call-history' and
909 'record instruction-history' commands are now inclusive.
911 * The btrace record target now supports the 'record goto' command.
912 For locations inside the execution trace, the back trace is computed
913 based on the information stored in the execution trace.
915 * The btrace record target supports limited reverse execution and replay.
916 The target does not record data and therefore does not allow reading
919 * The "catch syscall" command now works on s390*-linux* targets.
921 * The "compare-sections" command is no longer specific to target
922 remote. It now works with all targets.
924 * All native targets are now consistently called "native".
925 Consequently, the "target child", "target GNU", "target djgpp",
926 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
927 commands have been replaced with "target native". The QNX/NTO port
928 leaves the "procfs" target in place and adds a "native" target for
929 consistency with other ports. The impact on users should be minimal
930 as these commands previously either throwed an error, or were
931 no-ops. The target's name is visible in the output of the following
932 commands: "help target", "info target", "info files", "maint print
935 * The "target native" command now connects to the native target. This
936 can be used to launch native programs even when "set
937 auto-connect-native-target" is set to off.
939 * GDB now supports access to Intel MPX registers on GNU/Linux.
941 * Support for Intel AVX-512 registers on GNU/Linux.
942 Support displaying and modifying Intel AVX-512 registers
943 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
947 qXfer:btrace:read's annex
948 The qXfer:btrace:read packet supports a new annex 'delta' to read
949 branch trace incrementally.
953 ** Valid Python operations on gdb.Value objects representing
954 structs/classes invoke the corresponding overloaded operators if
956 ** New `Xmethods' feature in the Python API. Xmethods are
957 additional methods or replacements for existing methods of a C++
958 class. This feature is useful for those cases where a method
959 defined in C++ source code could be inlined or optimized out by
960 the compiler, making it unavailable to GDB.
963 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
965 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
966 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
967 its alias "share", instead.
969 * The commands "set remotebaud" and "show remotebaud" are no longer
970 supported. Use "set serial baud" and "show serial baud" (respectively)
975 ** A new option "-gdb-set mi-async" replaces "-gdb-set
976 target-async". The latter is left as a deprecated alias of the
977 former for backward compatibility. If the target supports it,
978 CLI background execution commands are now always possible by
979 default, independently of whether the frontend stated a
980 preference for asynchronous execution with "-gdb-set mi-async".
981 Previously "-gdb-set target-async off" affected both MI execution
982 commands and CLI execution commands.
984 *** Changes in GDB 7.7
986 * Improved support for process record-replay and reverse debugging on
987 arm*-linux* targets. Support for thumb32 and syscall instruction
988 recording has been added.
990 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
992 * GDB now supports Fission DWP file format version 2.
993 http://gcc.gnu.org/wiki/DebugFission
995 * New convenience function "$_isvoid", to check whether an expression
996 is void. A void expression is an expression where the type of the
997 result is "void". For example, some convenience variables may be
998 "void" when evaluated (e.g., "$_exitcode" before the execution of
999 the program being debugged; or an undefined convenience variable).
1000 Another example, when calling a function whose return type is
1003 * The "maintenance print objfiles" command now takes an optional regexp.
1005 * The "catch syscall" command now works on arm*-linux* targets.
1007 * GDB now consistently shows "<not saved>" when printing values of
1008 registers the debug info indicates have not been saved in the frame
1009 and there's nowhere to retrieve them from
1010 (callee-saved/call-clobbered registers):
1015 (gdb) info registers rax
1018 Before, the former would print "<optimized out>", and the latter
1019 "*value not available*".
1021 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1026 ** Frame filters and frame decorators have been added.
1027 ** Temporary breakpoints are now supported.
1028 ** Line tables representation has been added.
1029 ** New attribute 'parent_type' for gdb.Field objects.
1030 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1031 ** New attribute 'name' for gdb.Type objects.
1035 Nios II ELF nios2*-*-elf
1036 Nios II GNU/Linux nios2*-*-linux
1037 Texas Instruments MSP430 msp430*-*-elf
1039 * Removed native configurations
1041 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1042 been removed. ELF variants of these configurations are kept supported.
1044 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1045 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1046 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1047 i[34567]86-*-openbsd3.[0-3]
1048 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1049 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1050 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1054 Like "catch throw", but catches a re-thrown exception.
1055 maint check-psymtabs
1056 Renamed from old "maint check-symtabs".
1058 Perform consistency checks on symtabs.
1059 maint expand-symtabs
1060 Expand symtabs matching an optional regexp.
1063 Display the details of GDB configure-time options.
1065 maint set|show per-command
1066 maint set|show per-command space
1067 maint set|show per-command time
1068 maint set|show per-command symtab
1069 Enable display of per-command gdb resource usage.
1071 remove-symbol-file FILENAME
1072 remove-symbol-file -a ADDRESS
1073 Remove a symbol file added via add-symbol-file. The file to remove
1074 can be identified by its filename or by an address that lies within
1075 the boundaries of this symbol file in memory.
1078 info exceptions REGEXP
1079 Display the list of Ada exceptions defined in the program being
1080 debugged. If provided, only the exceptions whose names match REGEXP
1085 set debug symfile off|on
1087 Control display of debugging info regarding reading symbol files and
1088 symbol tables within those files
1090 set print raw frame-arguments
1091 show print raw frame-arguments
1092 Set/show whether to print frame arguments in raw mode,
1093 disregarding any defined pretty-printers.
1095 set remote trace-status-packet
1096 show remote trace-status-packet
1097 Set/show the use of remote protocol qTStatus packet.
1101 Control display of debugging messages related to Nios II targets.
1105 Control whether target-assisted range stepping is enabled.
1107 set startup-with-shell
1108 show startup-with-shell
1109 Specifies whether Unix child processes are started via a shell or
1114 Use the target memory cache for accesses to the code segment. This
1115 improves performance of remote debugging (particularly disassembly).
1117 * You can now use a literal value 'unlimited' for options that
1118 interpret 0 or -1 as meaning "unlimited". E.g., "set
1119 trace-buffer-size unlimited" is now an alias for "set
1120 trace-buffer-size -1" and "set height unlimited" is now an alias for
1123 * The "set debug symtab-create" debugging option of GDB has been changed to
1124 accept a verbosity level. 0 means "off", 1 provides basic debugging
1125 output, and values of 2 or greater provides more verbose output.
1127 * New command-line options
1129 Display the details of GDB configure-time options.
1131 * The command 'tsave' can now support new option '-ctf' to save trace
1132 buffer in Common Trace Format.
1134 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1137 * GDB now implements the the C++ 'typeid' operator.
1139 * The new convenience variable $_exception holds the exception being
1140 thrown or caught at an exception-related catchpoint.
1142 * The exception-related catchpoints, like "catch throw", now accept a
1143 regular expression which can be used to filter exceptions by type.
1145 * The new convenience variable $_exitsignal is automatically set to
1146 the terminating signal number when the program being debugged dies
1147 due to an uncaught signal.
1151 ** All MI commands now accept an optional "--language" option.
1152 Support for this feature can be verified by using the "-list-features"
1153 command, which should contain "language-option".
1155 ** The new command -info-gdb-mi-command allows the user to determine
1156 whether a GDB/MI command is supported or not.
1158 ** The "^error" result record returned when trying to execute an undefined
1159 GDB/MI command now provides a variable named "code" whose content is the
1160 "undefined-command" error code. Support for this feature can be verified
1161 by using the "-list-features" command, which should contain
1162 "undefined-command-error-code".
1164 ** The -trace-save MI command can optionally save trace buffer in Common
1167 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1169 ** The command -data-list-register-values now accepts an optional
1170 "--skip-unavailable" option. When used, only the available registers
1173 ** The new command -trace-frame-collected dumps collected variables,
1174 computed expressions, tvars, memory and registers in a traceframe.
1176 ** The commands -stack-list-locals, -stack-list-arguments and
1177 -stack-list-variables now accept an option "--skip-unavailable".
1178 When used, only the available locals or arguments are displayed.
1180 ** The -exec-run command now accepts an optional "--start" option.
1181 When used, the command follows the same semantics as the "start"
1182 command, stopping the program's execution at the start of its
1183 main subprogram. Support for this feature can be verified using
1184 the "-list-features" command, which should contain
1185 "exec-run-start-option".
1187 ** The new commands -catch-assert and -catch-exceptions insert
1188 catchpoints stopping the program when Ada exceptions are raised.
1190 ** The new command -info-ada-exceptions provides the equivalent of
1191 the new "info exceptions" command.
1193 * New system-wide configuration scripts
1194 A GDB installation now provides scripts suitable for use as system-wide
1195 configuration scripts for the following systems:
1199 * GDB now supports target-assigned range stepping with remote targets.
1200 This improves the performance of stepping source lines by reducing
1201 the number of control packets from/to GDB. See "New remote packets"
1204 * GDB now understands the element 'tvar' in the XML traceframe info.
1205 It has the id of the collected trace state variables.
1207 * On S/390 targets that provide the transactional-execution feature,
1208 the program interruption transaction diagnostic block (TDB) is now
1209 represented as a number of additional "registers" in GDB.
1211 * New remote packets
1215 The vCont packet supports a new 'r' action, that tells the remote
1216 stub to step through an address range itself, without GDB
1217 involvemement at each single-step.
1219 qXfer:libraries-svr4:read's annex
1220 The previously unused annex of the qXfer:libraries-svr4:read packet
1221 is now used to support passing an argument list. The remote stub
1222 reports support for this argument list to GDB's qSupported query.
1223 The defined arguments are "start" and "prev", used to reduce work
1224 necessary for library list updating, resulting in significant
1227 * New features in the GDB remote stub, GDBserver
1229 ** GDBserver now supports target-assisted range stepping. Currently
1230 enabled on x86/x86_64 GNU/Linux targets.
1232 ** GDBserver now adds element 'tvar' in the XML in the reply to
1233 'qXfer:traceframe-info:read'. It has the id of the collected
1234 trace state variables.
1236 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1239 * New 'z' formatter for printing and examining memory, this displays the
1240 value as hexadecimal zero padded on the left to the size of the type.
1242 * GDB can now use Windows x64 unwinding data.
1244 * The "set remotebaud" command has been replaced by "set serial baud".
1245 Similarly, "show remotebaud" has been replaced by "show serial baud".
1246 The "set remotebaud" and "show remotebaud" commands are still available
1247 to provide backward compatibility with older versions of GDB.
1249 *** Changes in GDB 7.6
1251 * Target record has been renamed to record-full.
1252 Record/replay is now enabled with the "record full" command.
1253 This also affects settings that are associated with full record/replay
1254 that have been moved from "set/show record" to "set/show record full":
1256 set|show record full insn-number-max
1257 set|show record full stop-at-limit
1258 set|show record full memory-query
1260 * A new record target "record-btrace" has been added. The new target
1261 uses hardware support to record the control-flow of a process. It
1262 does not support replaying the execution, but it implements the
1263 below new commands for investigating the recorded execution log.
1264 This new recording method can be enabled using:
1268 The "record-btrace" target is only available on Intel Atom processors
1269 and requires a Linux kernel 2.6.32 or later.
1271 * Two new commands have been added for record/replay to give information
1272 about the recorded execution without having to replay the execution.
1273 The commands are only supported by "record btrace".
1275 record instruction-history prints the execution history at
1276 instruction granularity
1278 record function-call-history prints the execution history at
1279 function granularity
1281 * New native configurations
1283 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1284 FreeBSD/powerpc powerpc*-*-freebsd
1285 x86_64/Cygwin x86_64-*-cygwin*
1286 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1290 ARM AArch64 aarch64*-*-elf
1291 ARM AArch64 GNU/Linux aarch64*-*-linux
1292 Lynx 178 PowerPC powerpc-*-lynx*178
1293 x86_64/Cygwin x86_64-*-cygwin*
1294 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1296 * If the configured location of system.gdbinit file (as given by the
1297 --with-system-gdbinit option at configure time) is in the
1298 data-directory (as specified by --with-gdb-datadir at configure
1299 time) or in one of its subdirectories, then GDB will look for the
1300 system-wide init file in the directory specified by the
1301 --data-directory command-line option.
1303 * New command line options:
1305 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1306 other initialization files, unlike -nx which disables all of them.
1308 * Removed command line options
1310 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1313 * The 'ptype' and 'whatis' commands now accept an argument to control
1316 * 'info proc' now works on some core files.
1320 ** Vectors can be created with gdb.Type.vector.
1322 ** Python's atexit.register now works in GDB.
1324 ** Types can be pretty-printed via a Python API.
1326 ** Python 3 is now supported (in addition to Python 2.4 or later)
1328 ** New class gdb.Architecture exposes GDB's internal representation
1329 of architecture in the Python API.
1331 ** New method Frame.architecture returns the gdb.Architecture object
1332 corresponding to the frame's architecture.
1334 * New Python-based convenience functions:
1336 ** $_memeq(buf1, buf2, length)
1337 ** $_streq(str1, str2)
1339 ** $_regex(str, regex)
1341 * The 'cd' command now defaults to using '~' (the home directory) if not
1344 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1345 default for GCC since November 2000.
1347 * The command 'forward-search' can now be abbreviated as 'fo'.
1349 * The command 'info tracepoints' can now display 'installed on target'
1350 or 'not installed on target' for each non-pending location of tracepoint.
1352 * New configure options
1354 --enable-libmcheck/--disable-libmcheck
1355 By default, development versions are built with -lmcheck on hosts
1356 that support it, in order to help track memory corruption issues.
1357 Release versions, on the other hand, are built without -lmcheck
1358 by default. The --enable-libmcheck/--disable-libmcheck configure
1359 options allow the user to override that default.
1360 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1361 This configure option allows the user to build GDB with
1362 libbabeltrace using which GDB can read Common Trace Format data.
1364 * New commands (for set/show, see "New options" below)
1367 Catch signals. This is similar to "handle", but allows commands and
1368 conditions to be attached.
1371 List the BFDs known to GDB.
1373 python-interactive [command]
1375 Start a Python interactive prompt, or evaluate the optional command
1376 and print the result of expressions.
1379 "py" is a new alias for "python".
1381 enable type-printer [name]...
1382 disable type-printer [name]...
1383 Enable or disable type printers.
1387 ** For the Renesas Super-H architecture, the "regs" command has been removed
1388 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1393 set print type methods (on|off)
1394 show print type methods
1395 Control whether method declarations are displayed by "ptype".
1396 The default is to show them.
1398 set print type typedefs (on|off)
1399 show print type typedefs
1400 Control whether typedef definitions are displayed by "ptype".
1401 The default is to show them.
1403 set filename-display basename|relative|absolute
1404 show filename-display
1405 Control the way in which filenames is displayed.
1406 The default is "relative", which preserves previous behavior.
1408 set trace-buffer-size
1409 show trace-buffer-size
1410 Request target to change the size of trace buffer.
1412 set remote trace-buffer-size-packet auto|on|off
1413 show remote trace-buffer-size-packet
1414 Control the use of the remote protocol `QTBuffer:size' packet.
1418 Control display of debugging messages related to ARM AArch64.
1421 set debug coff-pe-read
1422 show debug coff-pe-read
1423 Control display of debugging messages related to reading of COFF/PE
1428 Control display of debugging messages related to Mach-O symbols
1431 set debug notification
1432 show debug notification
1433 Control display of debugging info for async remote notification.
1437 ** Command parameter changes are now notified using new async record
1438 "=cmd-param-changed".
1439 ** Trace frame changes caused by command "tfind" are now notified using
1440 new async record "=traceframe-changed".
1441 ** The creation, deletion and modification of trace state variables
1442 are now notified using new async records "=tsv-created",
1443 "=tsv-deleted" and "=tsv-modified".
1444 ** The start and stop of process record are now notified using new
1445 async record "=record-started" and "=record-stopped".
1446 ** Memory changes are now notified using new async record
1448 ** The data-disassemble command response will include a "fullname" field
1449 containing the absolute file name when source has been requested.
1450 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1451 command, to allow pattern filling of memory areas.
1452 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1453 library load/unload events.
1454 ** The response to breakpoint commands and breakpoint async records
1455 includes an "installed" field containing a boolean state about each
1456 non-pending tracepoint location is whether installed on target or not.
1457 ** Output of the "-trace-status" command includes a "trace-file" field
1458 containing the name of the trace file being examined. This field is
1459 optional, and only present when examining a trace file.
1460 ** The "fullname" field is now always present along with the "file" field,
1461 even if the file cannot be found by GDB.
1463 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1464 You must have the LZMA library available when configuring GDB for this
1465 feature to be enabled. For more information, see:
1466 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1468 * New remote packets
1471 Set the size of trace buffer. The remote stub reports support for this
1472 packet to gdb's qSupported query.
1475 Enable Branch Trace Store (BTS)-based branch tracing for the current
1476 thread. The remote stub reports support for this packet to gdb's
1480 Disable branch tracing for the current thread. The remote stub reports
1481 support for this packet to gdb's qSupported query.
1484 Read the traced branches for the current thread. The remote stub
1485 reports support for this packet to gdb's qSupported query.
1487 *** Changes in GDB 7.5
1489 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1490 for more x32 ABI info.
1492 * GDB now supports access to MIPS DSP registers on Linux targets.
1494 * GDB now supports debugging microMIPS binaries.
1496 * The "info os" command on GNU/Linux can now display information on
1497 several new classes of objects managed by the operating system:
1498 "info os procgroups" lists process groups
1499 "info os files" lists file descriptors
1500 "info os sockets" lists internet-domain sockets
1501 "info os shm" lists shared-memory regions
1502 "info os semaphores" lists semaphores
1503 "info os msg" lists message queues
1504 "info os modules" lists loaded kernel modules
1506 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1507 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1508 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1509 options and inspect the probe arguments using the new $_probe_arg family
1510 of convenience variables. You can obtain more information about SystemTap
1511 in <http://sourceware.org/systemtap/>.
1513 * GDB now supports reversible debugging on ARM, it allows you to
1514 debug basic ARM and THUMB instructions, and provides
1515 record/replay support.
1517 * The option "symbol-reloading" has been deleted as it is no longer used.
1521 ** GDB commands implemented in Python can now be put in command class
1524 ** The "maint set python print-stack on|off" is now deleted.
1526 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1527 apply "flag enum"-style pretty-printing to any enum.
1529 ** gdb.lookup_symbol can now work when there is no current frame.
1531 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1532 the source at which the symbol was defined.
1534 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1535 method 'value'. The former indicates whether the symbol needs a
1536 frame in order to compute its value, and the latter computes the
1539 ** A new method 'referenced_value' on gdb.Value objects which can
1540 dereference pointer as well as C++ reference values.
1542 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1543 which return the global and static blocks (as gdb.Block objects),
1544 of the underlying symbol table, respectively.
1546 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1547 object associated with a PC value.
1549 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1550 of the address range occupied by code for the current source line.
1552 * Go language support.
1553 GDB now supports debugging programs written in the Go programming
1556 * GDBserver now supports stdio connections.
1557 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1559 * The binary "gdbtui" can no longer be built or installed.
1560 Use "gdb -tui" instead.
1562 * GDB will now print "flag" enums specially. A flag enum is one where
1563 all the enumerator values have no bits in common when pairwise
1564 "and"ed. When printing a value whose type is a flag enum, GDB will
1565 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1566 (gdb) print (enum E) 3
1569 * The filename part of a linespec will now match trailing components
1570 of a source file name. For example, "break gcc/expr.c:1000" will
1571 now set a breakpoint in build/gcc/expr.c, but not
1572 build/libcpp/expr.c.
1574 * The "info proc" and "generate-core-file" commands will now also
1575 work on remote targets connected to GDBserver on Linux.
1577 * The command "info catch" has been removed. It has been disabled
1578 since December 2007.
1580 * The "catch exception" and "catch assert" commands now accept
1581 a condition at the end of the command, much like the "break"
1582 command does. For instance:
1584 (gdb) catch exception Constraint_Error if Barrier = True
1586 Previously, it was possible to add a condition to such catchpoints,
1587 but it had to be done as a second step, after the catchpoint had been
1588 created, using the "condition" command.
1590 * The "info static-tracepoint-marker" command will now also work on
1591 native Linux targets with in-process agent.
1593 * GDB can now set breakpoints on inlined functions.
1595 * The .gdb_index section has been updated to include symbols for
1596 inlined functions. GDB will ignore older .gdb_index sections by
1597 default, which could cause symbol files to be loaded more slowly
1598 until their .gdb_index sections can be recreated. The new command
1599 "set use-deprecated-index-sections on" will cause GDB to use any older
1600 .gdb_index sections it finds. This will restore performance, but the
1601 ability to set breakpoints on inlined functions will be lost in symbol
1602 files with older .gdb_index sections.
1604 The .gdb_index section has also been updated to record more information
1605 about each symbol. This speeds up the "info variables", "info functions"
1606 and "info types" commands when used with programs having the .gdb_index
1607 section, as well as speeding up debugging with shared libraries using
1608 the .gdb_index section.
1610 * Ada support for GDB/MI Variable Objects has been added.
1612 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1617 ** New command -info-os is the MI equivalent of "info os".
1619 ** Output logs ("set logging" and related) now include MI output.
1623 ** "set use-deprecated-index-sections on|off"
1624 "show use-deprecated-index-sections on|off"
1625 Controls the use of deprecated .gdb_index sections.
1627 ** "catch load" and "catch unload" can be used to stop when a shared
1628 library is loaded or unloaded, respectively.
1630 ** "enable count" can be used to auto-disable a breakpoint after
1633 ** "info vtbl" can be used to show the virtual method tables for
1634 C++ and Java objects.
1636 ** "explore" and its sub commands "explore value" and "explore type"
1637 can be used to recursively explore values and types of
1638 expressions. These commands are available only if GDB is
1639 configured with '--with-python'.
1641 ** "info auto-load" shows status of all kinds of auto-loaded files,
1642 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1643 sequences of commands files, "info auto-load python-scripts"
1644 shows status of auto-loading Python script files,
1645 "info auto-load local-gdbinit" shows status of loading init file
1646 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1647 status of inferior specific thread debugging shared library loading.
1649 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1650 and "show auto-load-scripts" commands have been deprecated, use their
1651 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1652 and "show auto-load python-scripts" counterparts instead.
1654 ** "dprintf location,format,args..." creates a dynamic printf, which
1655 is basically a breakpoint that does a printf and immediately
1656 resumes your program's execution, so it is like a printf that you
1657 can insert dynamically at runtime instead of at compiletime.
1659 ** "set print symbol"
1661 Controls whether GDB attempts to display the symbol, if any,
1662 corresponding to addresses it prints. This defaults to "on", but
1663 you can set it to "off" to restore GDB's previous behavior.
1665 * Deprecated commands
1667 ** For the Renesas Super-H architecture, the "regs" command has been
1668 deprecated, and "info all-registers" should be used instead.
1672 Renesas RL78 rl78-*-elf
1673 HP OpenVMS ia64 ia64-hp-openvms*
1675 * GDBserver supports evaluation of breakpoint conditions. When
1676 support is advertised by GDBserver, GDB may be told to send the
1677 breakpoint conditions in bytecode form to GDBserver. GDBserver
1678 will only report the breakpoint trigger to GDB when its condition
1683 set mips compression
1684 show mips compression
1685 Select the compressed ISA encoding used in functions that have no symbol
1686 information available. The encoding can be set to either of:
1689 and is updated automatically from ELF file flags if available.
1691 set breakpoint condition-evaluation
1692 show breakpoint condition-evaluation
1693 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1694 GDBserver ("target"). Default option "auto" chooses the most efficient
1696 This option can improve debugger efficiency depending on the speed of the
1700 Disable auto-loading globally.
1703 Show auto-loading setting of all kinds of auto-loaded files.
1705 set auto-load gdb-scripts on|off
1706 show auto-load gdb-scripts
1707 Control auto-loading of GDB canned sequences of commands files.
1709 set auto-load python-scripts on|off
1710 show auto-load python-scripts
1711 Control auto-loading of Python script files.
1713 set auto-load local-gdbinit on|off
1714 show auto-load local-gdbinit
1715 Control loading of init file (.gdbinit) from current directory.
1717 set auto-load libthread-db on|off
1718 show auto-load libthread-db
1719 Control auto-loading of inferior specific thread debugging shared library.
1721 set auto-load scripts-directory <dir1>[:<dir2>...]
1722 show auto-load scripts-directory
1723 Set a list of directories from which to load auto-loaded scripts.
1724 Automatically loaded Python scripts and GDB scripts are located in one
1725 of the directories listed by this option.
1726 The delimiter (':' above) may differ according to the host platform.
1728 set auto-load safe-path <dir1>[:<dir2>...]
1729 show auto-load safe-path
1730 Set a list of directories from which it is safe to auto-load files.
1731 The delimiter (':' above) may differ according to the host platform.
1733 set debug auto-load on|off
1734 show debug auto-load
1735 Control display of debugging info for auto-loading the files above.
1737 set dprintf-style gdb|call|agent
1739 Control the way in which a dynamic printf is performed; "gdb"
1740 requests a GDB printf command, while "call" causes dprintf to call a
1741 function in the inferior. "agent" requests that the target agent
1742 (such as GDBserver) do the printing.
1744 set dprintf-function <expr>
1745 show dprintf-function
1746 set dprintf-channel <expr>
1747 show dprintf-channel
1748 Set the function and optional first argument to the call when using
1749 the "call" style of dynamic printf.
1751 set disconnected-dprintf on|off
1752 show disconnected-dprintf
1753 Control whether agent-style dynamic printfs continue to be in effect
1754 after GDB disconnects.
1756 * New configure options
1758 --with-auto-load-dir
1759 Configure default value for the 'set auto-load scripts-directory'
1760 setting above. It defaults to '$debugdir:$datadir/auto-load',
1761 $debugdir representing global debugging info directories (available
1762 via 'show debug-file-directory') and $datadir representing GDB's data
1763 directory (available via 'show data-directory').
1765 --with-auto-load-safe-path
1766 Configure default value for the 'set auto-load safe-path' setting
1767 above. It defaults to the --with-auto-load-dir setting.
1769 --without-auto-load-safe-path
1770 Set 'set auto-load safe-path' to '/', effectively disabling this
1773 * New remote packets
1775 z0/z1 conditional breakpoints extension
1777 The z0/z1 breakpoint insertion packets have been extended to carry
1778 a list of conditional expressions over to the remote stub depending on the
1779 condition evaluation mode. The use of this extension can be controlled
1780 via the "set remote conditional-breakpoints-packet" command.
1784 Specify the signals which the remote stub may pass to the debugged
1785 program without GDB involvement.
1787 * New command line options
1789 --init-command=FILE, -ix Like --command, -x but execute it
1790 before loading inferior.
1791 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1792 execute it before loading inferior.
1794 *** Changes in GDB 7.4
1796 * GDB now handles ambiguous linespecs more consistently; the existing
1797 FILE:LINE support has been expanded to other types of linespecs. A
1798 breakpoint will now be set on all matching locations in all
1799 inferiors, and locations will be added or removed according to
1802 * GDB now allows you to skip uninteresting functions and files when
1803 stepping with the "skip function" and "skip file" commands.
1805 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1806 and "show remote hardware-watchpoint-length-limit". These allows to
1807 set or show the maximum length limit (in bytes) of a remote
1808 target hardware watchpoint.
1810 This allows e.g. to use "unlimited" hardware watchpoints with the
1811 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1812 watchpoints are slower than real hardware watchpoints but are
1813 significantly faster than gdb software watchpoints.
1817 ** The register_pretty_printer function in module gdb.printing now takes
1818 an optional `replace' argument. If True, the new printer replaces any
1821 ** The "maint set python print-stack on|off" command has been
1822 deprecated and will be deleted in GDB 7.5.
1823 A new command: "set python print-stack none|full|message" has
1824 replaced it. Additionally, the default for "print-stack" is
1825 now "message", which just prints the error message without
1828 ** A prompt substitution hook (prompt_hook) is now available to the
1831 ** A new Python module, gdb.prompt has been added to the GDB Python
1832 modules library. This module provides functionality for
1833 escape sequences in prompts (used by set/show
1834 extended-prompt). These escape sequences are replaced by their
1835 corresponding value.
1837 ** Python commands and convenience-functions located in
1838 'data-directory'/python/gdb/command and
1839 'data-directory'/python/gdb/function are now automatically loaded
1842 ** Blocks now provide four new attributes. global_block and
1843 static_block will return the global and static blocks
1844 respectively. is_static and is_global are boolean attributes
1845 that indicate if the block is one of those two types.
1847 ** Symbols now provide the "type" attribute, the type of the symbol.
1849 ** The "gdb.breakpoint" function has been deprecated in favor of
1852 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1853 of a function. This class is based on the "finish" command
1854 available in the CLI.
1856 ** Type objects for struct and union types now allow access to
1857 the fields using standard Python dictionary (mapping) methods.
1858 For example, "some_type['myfield']" now works, as does
1859 "some_type.items()".
1861 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1864 ** A new function, "deep_items" has been added to the gdb.types
1865 module in the GDB Python modules library. This function returns
1866 an iterator over the fields of a struct or union type. Unlike
1867 the standard Python "iteritems" method, it will recursively traverse
1868 any anonymous fields.
1872 ** "*stopped" events can report several new "reason"s, such as
1875 ** Breakpoint changes are now notified using new async records, like
1876 "=breakpoint-modified".
1878 ** New command -ada-task-info.
1880 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1881 $sdir specifies the default system locations of shared libraries.
1882 $pdir specifies the directory where the libpthread used by the application
1885 GDB no longer looks in $sdir and $pdir after it has searched the directories
1886 mentioned in libthread-db-search-path. If you want to search those
1887 directories, they must be specified in libthread-db-search-path.
1888 The default value of libthread-db-search-path on GNU/Linux and Solaris
1889 systems is now "$sdir:$pdir".
1891 $pdir is not supported by gdbserver, it is currently ignored.
1892 $sdir is supported by gdbserver.
1894 * New configure option --with-iconv-bin.
1895 When using the internationalization support like the one in the GNU C
1896 library, GDB will invoke the "iconv" program to get a list of supported
1897 character sets. If this program lives in a non-standard location, one can
1898 use this option to specify where to find it.
1900 * When natively debugging programs on PowerPC BookE processors running
1901 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1902 watchpoints, which specify a mask in addition to an address to watch.
1903 The mask specifies that some bits of an address (the bits which are
1904 reset in the mask) should be ignored when matching the address accessed
1905 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1906 section in the user manual for more details.
1908 * The new option --once causes GDBserver to stop listening for connections once
1909 the first connection is made. The listening port used by GDBserver will
1910 become available after that.
1912 * New commands "info macros" and "alias" have been added.
1914 * New function parameters suffix @entry specifies value of function parameter
1915 at the time the function got called. Entry values are available only since
1921 "!" is now an alias of the "shell" command.
1922 Note that no space is needed between "!" and SHELL COMMAND.
1926 watch EXPRESSION mask MASK_VALUE
1927 The watch command now supports the mask argument which allows creation
1928 of masked watchpoints, if the current architecture supports this feature.
1930 info auto-load-scripts [REGEXP]
1931 This command was formerly named "maintenance print section-scripts".
1932 It is now generally useful and is no longer a maintenance-only command.
1934 info macro [-all] [--] MACRO
1935 The info macro command has new options `-all' and `--'. The first for
1936 printing all definitions of a macro. The second for explicitly specifying
1937 the end of arguments and the beginning of the macro name in case the macro
1938 name starts with a hyphen.
1940 collect[/s] EXPRESSIONS
1941 The tracepoint collect command now takes an optional modifier "/s"
1942 that directs it to dereference pointer-to-character types and
1943 collect the bytes of memory up to a zero byte. The behavior is
1944 similar to what you see when you use the regular print command on a
1945 string. An optional integer following the "/s" sets a bound on the
1946 number of bytes that will be collected.
1949 The trace start command now interprets any supplied arguments as a
1950 note to be recorded with the trace run, with an effect similar to
1951 setting the variable trace-notes.
1954 The trace stop command now interprets any arguments as a note to be
1955 mentioned along with the tstatus report that the trace was stopped
1956 with a command. The effect is similar to setting the variable
1959 * Tracepoints can now be enabled and disabled at any time after a trace
1960 experiment has been started using the standard "enable" and "disable"
1961 commands. It is now possible to start a trace experiment with no enabled
1962 tracepoints; GDB will display a warning, but will allow the experiment to
1963 begin, assuming that tracepoints will be enabled as needed while the trace
1966 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1967 locations with 4-byte instructions, when they were previously
1968 limited to locations with instructions of 5 bytes or longer.
1972 set debug dwarf2-read
1973 show debug dwarf2-read
1974 Turns on or off display of debugging messages related to reading
1975 DWARF debug info. The default is off.
1977 set debug symtab-create
1978 show debug symtab-create
1979 Turns on or off display of debugging messages related to symbol table
1980 creation. The default is off.
1983 show extended-prompt
1984 Set the GDB prompt, and allow escape sequences to be inserted to
1985 display miscellaneous information (see 'help set extended-prompt'
1986 for the list of sequences). This prompt (and any information
1987 accessed through the escape sequences) is updated every time the
1988 prompt is displayed.
1990 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1991 show print entry-values
1992 Set printing of frame argument values at function entry. In some cases
1993 GDB can determine the value of function argument which was passed by the
1994 function caller, even if the value was modified inside the called function.
1996 set debug entry-values
1997 show debug entry-values
1998 Control display of debugging info for determining frame argument values at
1999 function entry and virtual tail call frames.
2001 set basenames-may-differ
2002 show basenames-may-differ
2003 Set whether a source file may have multiple base names.
2004 (A "base name" is the name of a file with the directory part removed.
2005 Example: The base name of "/home/user/hello.c" is "hello.c".)
2006 If set, GDB will canonicalize file names (e.g., expand symlinks)
2007 before comparing them. Canonicalization is an expensive operation,
2008 but it allows the same file be known by more than one base name.
2009 If not set (the default), all source files are assumed to have just
2010 one base name, and gdb will do file name comparisons more efficiently.
2016 Set a user name and notes for the current and any future trace runs.
2017 This is useful for long-running and/or disconnected traces, to
2018 inform others (or yourself) as to who is running the trace, supply
2019 contact information, or otherwise explain what is going on.
2021 set trace-stop-notes
2022 show trace-stop-notes
2023 Set a note attached to the trace run, that is displayed when the
2024 trace has been stopped by a tstop command. This is useful for
2025 instance as an explanation, if you are stopping a trace run that was
2026 started by someone else.
2028 * New remote packets
2032 Dynamically enable a tracepoint in a started trace experiment.
2036 Dynamically disable a tracepoint in a started trace experiment.
2040 Set the user and notes of the trace run.
2044 Query the current status of a tracepoint.
2048 Query the minimum length of instruction at which a fast tracepoint may
2051 * Dcache size (number of lines) and line-size are now runtime-configurable
2052 via "set dcache line" and "set dcache line-size" commands.
2056 Texas Instruments TMS320C6x tic6x-*-*
2060 Renesas RL78 rl78-*-elf
2062 *** Changes in GDB 7.3.1
2064 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2066 *** Changes in GDB 7.3
2068 * GDB has a new command: "thread find [REGEXP]".
2069 It finds the thread id whose name, target id, or thread extra info
2070 matches the given regular expression.
2072 * The "catch syscall" command now works on mips*-linux* targets.
2074 * The -data-disassemble MI command now supports modes 2 and 3 for
2075 dumping the instruction opcodes.
2077 * New command line options
2079 -data-directory DIR Specify DIR as the "data-directory".
2080 This is mostly for testing purposes.
2082 * The "maint set python auto-load on|off" command has been renamed to
2083 "set auto-load-scripts on|off".
2085 * GDB has a new command: "set directories".
2086 It is like the "dir" command except that it replaces the
2087 source path list instead of augmenting it.
2089 * GDB now understands thread names.
2091 On GNU/Linux, "info threads" will display the thread name as set by
2092 prctl or pthread_setname_np.
2094 There is also a new command, "thread name", which can be used to
2095 assign a name internally for GDB to display.
2098 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2099 has been integrated into GDB.
2103 ** The function gdb.Write now accepts an optional keyword 'stream'.
2104 This keyword, when provided, will direct the output to either
2105 stdout, stderr, or GDB's logging output.
2107 ** Parameters can now be be sub-classed in Python, and in particular
2108 you may implement the get_set_doc and get_show_doc functions.
2109 This improves how Parameter set/show documentation is processed
2110 and allows for more dynamic content.
2112 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2113 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2114 have an is_valid method.
2116 ** Breakpoints can now be sub-classed in Python, and in particular
2117 you may implement a 'stop' function that is executed each time
2118 the inferior reaches that breakpoint.
2120 ** New function gdb.lookup_global_symbol looks up a global symbol.
2122 ** GDB values in Python are now callable if the value represents a
2123 function. For example, if 'some_value' represents a function that
2124 takes two integer parameters and returns a value, you can call
2125 that function like so:
2127 result = some_value (10,20)
2129 ** Module gdb.types has been added.
2130 It contains a collection of utilities for working with gdb.Types objects:
2131 get_basic_type, has_field, make_enum_dict.
2133 ** Module gdb.printing has been added.
2134 It contains utilities for writing and registering pretty-printers.
2135 New classes: PrettyPrinter, SubPrettyPrinter,
2136 RegexpCollectionPrettyPrinter.
2137 New function: register_pretty_printer.
2139 ** New commands "info pretty-printers", "enable pretty-printer" and
2140 "disable pretty-printer" have been added.
2142 ** gdb.parameter("directories") is now available.
2144 ** New function gdb.newest_frame returns the newest frame in the
2147 ** The gdb.InferiorThread class has a new "name" attribute. This
2148 holds the thread's name.
2150 ** Python Support for Inferior events.
2151 Python scripts can add observers to be notified of events
2152 occurring in the process being debugged.
2153 The following events are currently supported:
2154 - gdb.events.cont Continue event.
2155 - gdb.events.exited Inferior exited event.
2156 - gdb.events.stop Signal received, and Breakpoint hit events.
2160 ** GDB now puts template parameters in scope when debugging in an
2161 instantiation. For example, if you have:
2163 template<int X> int func (void) { return X; }
2165 then if you step into func<5>, "print X" will show "5". This
2166 feature requires proper debuginfo support from the compiler; it
2167 was added to GCC 4.5.
2169 ** The motion commands "next", "finish", "until", and "advance" now
2170 work better when exceptions are thrown. In particular, GDB will
2171 no longer lose control of the inferior; instead, the GDB will
2172 stop the inferior at the point at which the exception is caught.
2173 This functionality requires a change in the exception handling
2174 code that was introduced in GCC 4.5.
2176 * GDB now follows GCC's rules on accessing volatile objects when
2177 reading or writing target state during expression evaluation.
2178 One notable difference to prior behavior is that "print x = 0"
2179 no longer generates a read of x; the value of the assignment is
2180 now always taken directly from the value being assigned.
2182 * GDB now has some support for using labels in the program's source in
2183 linespecs. For instance, you can use "advance label" to continue
2184 execution to a label.
2186 * GDB now has support for reading and writing a new .gdb_index
2187 section. This section holds a fast index of DWARF debugging
2188 information and can be used to greatly speed up GDB startup and
2189 operation. See the documentation for `save gdb-index' for details.
2191 * The "watch" command now accepts an optional "-location" argument.
2192 When used, this causes GDB to watch the memory referred to by the
2193 expression. Such a watchpoint is never deleted due to it going out
2196 * GDB now supports thread debugging of core dumps on GNU/Linux.
2198 GDB now activates thread debugging using the libthread_db library
2199 when debugging GNU/Linux core dumps, similarly to when debugging
2200 live processes. As a result, when debugging a core dump file, GDB
2201 is now able to display pthread_t ids of threads. For example, "info
2202 threads" shows the same output as when debugging the process when it
2203 was live. In earlier releases, you'd see something like this:
2206 * 1 LWP 6780 main () at main.c:10
2208 While now you see this:
2211 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2213 It is also now possible to inspect TLS variables when debugging core
2216 When debugging a core dump generated on a machine other than the one
2217 used to run GDB, you may need to point GDB at the correct
2218 libthread_db library with the "set libthread-db-search-path"
2219 command. See the user manual for more details on this command.
2221 * When natively debugging programs on PowerPC BookE processors running
2222 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2223 which stop execution of the inferior whenever it executes an instruction
2224 at any address within the specified range. See the "PowerPC Embedded"
2225 section in the user manual for more details.
2227 * New features in the GDB remote stub, GDBserver
2229 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2230 and i686 LynxOS (version 5.x).
2232 ** GDBserver is now supported on Blackfin Linux.
2234 * New native configurations
2236 ia64 HP-UX ia64-*-hpux*
2240 Analog Devices, Inc. Blackfin Processor bfin-*
2242 * Ada task switching is now supported on sparc-elf targets when
2243 debugging a program using the Ravenscar Profile. For more information,
2244 see the "Tasking Support when using the Ravenscar Profile" section
2245 in the GDB user manual.
2247 * Guile support was removed.
2249 * New features in the GNU simulator
2251 ** The --map-info flag lists all known core mappings.
2253 ** CFI flashes may be simulated via the "cfi" device.
2255 *** Changes in GDB 7.2
2257 * Shared library support for remote targets by default
2259 When GDB is configured for a generic, non-OS specific target, like
2260 for example, --target=arm-eabi or one of the many *-*-elf targets,
2261 GDB now queries remote stubs for loaded shared libraries using the
2262 `qXfer:libraries:read' packet. Previously, shared library support
2263 was always disabled for such configurations.
2267 ** Argument Dependent Lookup (ADL)
2269 In C++ ADL lookup directs function search to the namespaces of its
2270 arguments even if the namespace has not been imported.
2280 Here the compiler will search for `foo' in the namespace of 'b'
2281 and find A::foo. GDB now supports this. This construct is commonly
2282 used in the Standard Template Library for operators.
2284 ** Improved User Defined Operator Support
2286 In addition to member operators, GDB now supports lookup of operators
2287 defined in a namespace and imported with a `using' directive, operators
2288 defined in the global scope, operators imported implicitly from an
2289 anonymous namespace, and the ADL operators mentioned in the previous
2291 GDB now also supports proper overload resolution for all the previously
2292 mentioned flavors of operators.
2294 ** static const class members
2296 Printing of static const class members that are initialized in the
2297 class definition has been fixed.
2299 * Windows Thread Information Block access.
2301 On Windows targets, GDB now supports displaying the Windows Thread
2302 Information Block (TIB) structure. This structure is visible either
2303 by using the new command `info w32 thread-information-block' or, by
2304 dereferencing the new convenience variable named `$_tlb', a
2305 thread-specific pointer to the TIB. This feature is also supported
2306 when remote debugging using GDBserver.
2308 * Static tracepoints
2310 Static tracepoints are calls in the user program into a tracing
2311 library. One such library is a port of the LTTng kernel tracer to
2312 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2313 When debugging with GDBserver, GDB now supports combining the GDB
2314 tracepoint machinery with such libraries. For example: the user can
2315 use GDB to probe a static tracepoint marker (a call from the user
2316 program into the tracing library) with the new "strace" command (see
2317 "New commands" below). This creates a "static tracepoint" in the
2318 breakpoint list, that can be manipulated with the same feature set
2319 as fast and regular tracepoints. E.g., collect registers, local and
2320 global variables, collect trace state variables, and define
2321 tracepoint conditions. In addition, the user can collect extra
2322 static tracepoint marker specific data, by collecting the new
2323 $_sdata internal variable. When analyzing the trace buffer, you can
2324 inspect $_sdata like any other variable available to GDB. For more
2325 information, see the "Tracepoints" chapter in GDB user manual. New
2326 remote packets have been defined to support static tracepoints, see
2327 the "New remote packets" section below.
2329 * Better reconstruction of tracepoints after disconnected tracing
2331 GDB will attempt to download the original source form of tracepoint
2332 definitions when starting a trace run, and then will upload these
2333 upon reconnection to the target, resulting in a more accurate
2334 reconstruction of the tracepoints that are in use on the target.
2338 You can now exercise direct control over the ways that GDB can
2339 affect your program. For instance, you can disallow the setting of
2340 breakpoints, so that the program can run continuously (assuming
2341 non-stop mode). In addition, the "observer" variable is available
2342 to switch all of the different controls; in observer mode, GDB
2343 cannot affect the target's behavior at all, which is useful for
2344 tasks like diagnosing live systems in the field.
2346 * The new convenience variable $_thread holds the number of the
2349 * New remote packets
2353 Return the address of the Windows Thread Information Block of a given thread.
2357 In response to several of the tracepoint packets, the target may now
2358 also respond with a number of intermediate `qRelocInsn' request
2359 packets before the final result packet, to have GDB handle
2360 relocating an instruction to execute at a different address. This
2361 is particularly useful for stubs that support fast tracepoints. GDB
2362 reports support for this feature in the qSupported packet.
2366 List static tracepoint markers in the target program.
2370 List static tracepoint markers at a given address in the target
2373 qXfer:statictrace:read
2375 Read the static trace data collected (by a `collect $_sdata'
2376 tracepoint action). The remote stub reports support for this packet
2377 to gdb's qSupported query.
2381 Send the current settings of GDB's permission flags.
2385 Send part of the source (textual) form of a tracepoint definition,
2386 which includes location, conditional, and action list.
2388 * The source command now accepts a -s option to force searching for the
2389 script in the source search path even if the script name specifies
2392 * New features in the GDB remote stub, GDBserver
2394 - GDBserver now support tracepoints (including fast tracepoints, and
2395 static tracepoints). The feature is currently supported by the
2396 i386-linux and amd64-linux builds. See the "Tracepoints support
2397 in gdbserver" section in the manual for more information.
2399 GDBserver JIT compiles the tracepoint's conditional agent
2400 expression bytecode into native code whenever possible for low
2401 overhead dynamic tracepoints conditionals. For such tracepoints,
2402 an expression that examines program state is evaluated when the
2403 tracepoint is reached, in order to determine whether to capture
2404 trace data. If the condition is simple and false, processing the
2405 tracepoint finishes very quickly and no data is gathered.
2407 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2408 for static tracepoints support.
2410 - GDBserver now supports x86_64 Windows 64-bit debugging.
2412 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2413 it understands register description.
2415 * The --batch flag now disables pagination and queries.
2417 * X86 general purpose registers
2419 GDB now supports reading/writing byte, word and double-word x86
2420 general purpose registers directly. This means you can use, say,
2421 $ah or $ax to refer, respectively, to the byte register AH and
2422 16-bit word register AX that are actually portions of the 32-bit
2423 register EAX or 64-bit register RAX.
2425 * The `commands' command now accepts a range of breakpoints to modify.
2426 A plain `commands' following a command that creates multiple
2427 breakpoints affects all the breakpoints set by that command. This
2428 applies to breakpoints set by `rbreak', and also applies when a
2429 single `break' command creates multiple breakpoints (e.g.,
2430 breakpoints on overloaded c++ functions).
2432 * The `rbreak' command now accepts a filename specification as part of
2433 its argument, limiting the functions selected by the regex to those
2434 in the specified file.
2436 * Support for remote debugging Windows and SymbianOS shared libraries
2437 from Unix hosts has been improved. Non Windows GDB builds now can
2438 understand target reported file names that follow MS-DOS based file
2439 system semantics, such as file names that include drive letters and
2440 use the backslash character as directory separator. This makes it
2441 possible to transparently use the "set sysroot" and "set
2442 solib-search-path" on Unix hosts to point as host copies of the
2443 target's shared libraries. See the new command "set
2444 target-file-system-kind" described below, and the "Commands to
2445 specify files" section in the user manual for more information.
2449 eval template, expressions...
2450 Convert the values of one or more expressions under the control
2451 of the string template to a command line, and call it.
2453 set target-file-system-kind unix|dos-based|auto
2454 show target-file-system-kind
2455 Set or show the assumed file system kind for target reported file
2458 save breakpoints <filename>
2459 Save all current breakpoint definitions to a file suitable for use
2460 in a later debugging session. To read the saved breakpoint
2461 definitions, use the `source' command.
2463 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2466 info static-tracepoint-markers
2467 Display information about static tracepoint markers in the target.
2469 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2470 Define a static tracepoint by probing a marker at the given
2471 function, line, address, or marker ID.
2475 Enable and disable observer mode.
2477 set may-write-registers on|off
2478 set may-write-memory on|off
2479 set may-insert-breakpoints on|off
2480 set may-insert-tracepoints on|off
2481 set may-insert-fast-tracepoints on|off
2482 set may-interrupt on|off
2483 Set individual permissions for GDB effects on the target. Note that
2484 some of these settings can have undesirable or surprising
2485 consequences, particularly when changed in the middle of a session.
2486 For instance, disabling the writing of memory can prevent
2487 breakpoints from being inserted, cause single-stepping to fail, or
2488 even crash your program, if you disable after breakpoints have been
2489 inserted. However, GDB should not crash.
2491 set record memory-query on|off
2492 show record memory-query
2493 Control whether to stop the inferior if memory changes caused
2494 by an instruction cannot be recorded.
2499 The disassemble command now supports "start,+length" form of two arguments.
2503 ** GDB now provides a new directory location, called the python directory,
2504 where Python scripts written for GDB can be installed. The location
2505 of that directory is <data-directory>/python, where <data-directory>
2506 is the GDB data directory. For more details, see section `Scripting
2507 GDB using Python' in the manual.
2509 ** The GDB Python API now has access to breakpoints, symbols, symbol
2510 tables, program spaces, inferiors, threads and frame's code blocks.
2511 Additionally, GDB Parameters can now be created from the API, and
2512 manipulated via set/show in the CLI.
2514 ** New functions gdb.target_charset, gdb.target_wide_charset,
2515 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2517 ** New exception gdb.GdbError.
2519 ** Pretty-printers are now also looked up in the current program space.
2521 ** Pretty-printers can now be individually enabled and disabled.
2523 ** GDB now looks for names of Python scripts to auto-load in a
2524 special section named `.debug_gdb_scripts', in addition to looking
2525 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2527 * Tracepoint actions were unified with breakpoint commands. In particular,
2528 there are no longer differences in "info break" output for breakpoints and
2529 tracepoints and the "commands" command can be used for both tracepoints and
2530 regular breakpoints.
2534 ARM Symbian arm*-*-symbianelf*
2536 * D language support.
2537 GDB now supports debugging programs written in the D programming
2540 * GDB now supports the extended ptrace interface for PowerPC which is
2541 available since Linux kernel version 2.6.34. This automatically enables
2542 any hardware breakpoints and additional hardware watchpoints available in
2543 the processor. The old ptrace interface exposes just one hardware
2544 watchpoint and no hardware breakpoints.
2546 * GDB is now able to use the Data Value Compare (DVC) register available on
2547 embedded PowerPC processors to implement in hardware simple watchpoint
2548 conditions of the form:
2550 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2552 This works in native GDB running on Linux kernels with the extended ptrace
2553 interface mentioned above.
2555 *** Changes in GDB 7.1
2559 ** Namespace Support
2561 GDB now supports importing of namespaces in C++. This enables the
2562 user to inspect variables from imported namespaces. Support for
2563 namepace aliasing has also been added. So, if a namespace is
2564 aliased in the current scope (e.g. namepace C=A; ) the user can
2565 print variables using the alias (e.g. (gdb) print C::x).
2569 All known bugs relating to the printing of virtual base class were
2570 fixed. It is now possible to call overloaded static methods using a
2575 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2576 and reinterpret_cast<> are now handled by the C++ expression parser.
2580 Xilinx MicroBlaze microblaze-*-*
2585 Xilinx MicroBlaze microblaze
2588 * Multi-program debugging.
2590 GDB now has support for multi-program (a.k.a. multi-executable or
2591 multi-exec) debugging. This allows for debugging multiple inferiors
2592 simultaneously each running a different program under the same GDB
2593 session. See "Debugging Multiple Inferiors and Programs" in the
2594 manual for more information. This implied some user visible changes
2595 in the multi-inferior support. For example, "info inferiors" now
2596 lists inferiors that are not running yet or that have exited
2597 already. See also "New commands" and "New options" below.
2599 * New tracing features
2601 GDB's tracepoint facility now includes several new features:
2603 ** Trace state variables
2605 GDB tracepoints now include support for trace state variables, which
2606 are variables managed by the target agent during a tracing
2607 experiment. They are useful for tracepoints that trigger each
2608 other, so for instance one tracepoint can count hits in a variable,
2609 and then a second tracepoint has a condition that is true when the
2610 count reaches a particular value. Trace state variables share the
2611 $-syntax of GDB convenience variables, and can appear in both
2612 tracepoint actions and condition expressions. Use the "tvariable"
2613 command to create, and "info tvariables" to view; see "Trace State
2614 Variables" in the manual for more detail.
2618 GDB now includes an option for defining fast tracepoints, which
2619 targets may implement more efficiently, such as by installing a jump
2620 into the target agent rather than a trap instruction. The resulting
2621 speedup can be by two orders of magnitude or more, although the
2622 tradeoff is that some program locations on some target architectures
2623 might not allow fast tracepoint installation, for instance if the
2624 instruction to be replaced is shorter than the jump. To request a
2625 fast tracepoint, use the "ftrace" command, with syntax identical to
2626 the regular trace command.
2628 ** Disconnected tracing
2630 It is now possible to detach GDB from the target while it is running
2631 a trace experiment, then reconnect later to see how the experiment
2632 is going. In addition, a new variable disconnected-tracing lets you
2633 tell the target agent whether to continue running a trace if the
2634 connection is lost unexpectedly.
2638 GDB now has the ability to save the trace buffer into a file, and
2639 then use that file as a target, similarly to you can do with
2640 corefiles. You can select trace frames, print data that was
2641 collected in them, and use tstatus to display the state of the
2642 tracing run at the moment that it was saved. To create a trace
2643 file, use "tsave <filename>", and to use it, do "target tfile
2646 ** Circular trace buffer
2648 You can ask the target agent to handle the trace buffer as a
2649 circular buffer, discarding the oldest trace frames to make room for
2650 newer ones, by setting circular-trace-buffer to on. This feature may
2651 not be available for all target agents.
2656 The disassemble command, when invoked with two arguments, now requires
2657 the arguments to be comma-separated.
2660 The info variables command now displays variable definitions. Files
2661 which only declare a variable are not shown.
2664 The source command is now capable of sourcing Python scripts.
2665 This feature is dependent on the debugger being build with Python
2668 Related to this enhancement is also the introduction of a new command
2669 "set script-extension" (see below).
2671 * New commands (for set/show, see "New options" below)
2673 record save [<FILENAME>]
2674 Save a file (in core file format) containing the process record
2675 execution log for replay debugging at a later time.
2677 record restore <FILENAME>
2678 Restore the process record execution log that was saved at an
2679 earlier time, for replay debugging.
2681 add-inferior [-copies <N>] [-exec <FILENAME>]
2684 clone-inferior [-copies <N>] [ID]
2685 Make a new inferior ready to execute the same program another
2686 inferior has loaded.
2691 maint info program-spaces
2692 List the program spaces loaded into GDB.
2694 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2695 show remote interrupt-sequence
2696 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2697 as the sequence to the remote target in order to interrupt the execution.
2698 Ctrl-C is a default. Some system prefers BREAK which is high level of
2699 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2700 Magic SysRq g. It is BREAK signal and character 'g'.
2702 set remote interrupt-on-connect [on | off]
2703 show remote interrupt-on-connect
2704 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2705 remote target when gdb connects to it. This is needed when you debug
2708 set remotebreak [on | off]
2710 Deprecated. Use "set/show remote interrupt-sequence" instead.
2712 tvariable $NAME [ = EXP ]
2713 Create or modify a trace state variable.
2716 List trace state variables and their values.
2718 delete tvariable $NAME ...
2719 Delete one or more trace state variables.
2722 Evaluate the given expressions without collecting anything into the
2723 trace buffer. (Valid in tracepoint actions only.)
2725 ftrace FN / FILE:LINE / *ADDR
2726 Define a fast tracepoint at the given function, line, or address.
2728 * New expression syntax
2730 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2731 GDB now parses 0b101010 identically with 42.
2735 set follow-exec-mode new|same
2736 show follow-exec-mode
2737 Control whether GDB reuses the same inferior across an exec call or
2738 creates a new one. This is useful to be able to restart the old
2739 executable after the inferior having done an exec call.
2741 set default-collect EXPR, ...
2742 show default-collect
2743 Define a list of expressions to be collected at each tracepoint.
2744 This is a useful way to ensure essential items are not overlooked,
2745 such as registers or a critical global variable.
2747 set disconnected-tracing
2748 show disconnected-tracing
2749 If set to 1, the target is instructed to continue tracing if it
2750 loses its connection to GDB. If 0, the target is to stop tracing
2753 set circular-trace-buffer
2754 show circular-trace-buffer
2755 If set to on, the target is instructed to use a circular trace buffer
2756 and discard the oldest trace frames instead of stopping the trace due
2757 to a full trace buffer. If set to off, the trace stops when the buffer
2758 fills up. Some targets may not support this.
2760 set script-extension off|soft|strict
2761 show script-extension
2762 If set to "off", the debugger does not perform any script language
2763 recognition, and all sourced files are assumed to be GDB scripts.
2764 If set to "soft" (the default), files are sourced according to
2765 filename extension, falling back to GDB scripts if the first
2767 If set to "strict", files are sourced according to filename extension.
2769 set ada trust-PAD-over-XVS on|off
2770 show ada trust-PAD-over-XVS
2771 If off, activate a workaround against a bug in the debugging information
2772 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2773 the GCC sources for more information about the GNAT encoding and
2774 PAD types in particular). It is always safe to set this option to
2775 off, but this introduces a slight performance penalty. The default
2778 * Python API Improvements
2780 ** GDB provides the new class gdb.LazyString. This is useful in
2781 some pretty-printing cases. The new method gdb.Value.lazy_string
2782 provides a simple way to create objects of this type.
2784 ** The fields returned by gdb.Type.fields now have an
2785 `is_base_class' attribute.
2787 ** The new method gdb.Type.range returns the range of an array type.
2789 ** The new method gdb.parse_and_eval can be used to parse and
2790 evaluate an expression.
2792 * New remote packets
2795 Define a trace state variable.
2798 Get the current value of a trace state variable.
2801 Set desired tracing behavior upon disconnection.
2804 Set the trace buffer to be linear or circular.
2807 Get data about the tracepoints currently in use.
2811 Process record now works correctly with hardware watchpoints.
2813 Multiple bug fixes have been made to the mips-irix port, making it
2814 much more reliable. In particular:
2815 - Debugging threaded applications is now possible again. Previously,
2816 GDB would hang while starting the program, or while waiting for
2817 the program to stop at a breakpoint.
2818 - Attaching to a running process no longer hangs.
2819 - An error occurring while loading a core file has been fixed.
2820 - Changing the value of the PC register now works again. This fixes
2821 problems observed when using the "jump" command, or when calling
2822 a function from GDB, or even when assigning a new value to $pc.
2823 - With the "finish" and "return" commands, the return value for functions
2824 returning a small array is now correctly printed.
2825 - It is now possible to break on shared library code which gets executed
2826 during a shared library init phase (code executed while executing
2827 their .init section). Previously, the breakpoint would have no effect.
2828 - GDB is now able to backtrace through the signal handler for
2829 non-threaded programs.
2831 PIE (Position Independent Executable) programs debugging is now supported.
2832 This includes debugging execution of PIC (Position Independent Code) shared
2833 libraries although for that, it should be possible to run such libraries as an
2836 *** Changes in GDB 7.0
2838 * GDB now has an interface for JIT compilation. Applications that
2839 dynamically generate code can create symbol files in memory and register
2840 them with GDB. For users, the feature should work transparently, and
2841 for JIT developers, the interface is documented in the GDB manual in the
2842 "JIT Compilation Interface" chapter.
2844 * Tracepoints may now be conditional. The syntax is as for
2845 breakpoints; either an "if" clause appended to the "trace" command,
2846 or the "condition" command is available. GDB sends the condition to
2847 the target for evaluation using the same bytecode format as is used
2848 for tracepoint actions.
2850 * The disassemble command now supports: an optional /r modifier, print the
2851 raw instructions in hex as well as in symbolic form, and an optional /m
2852 modifier to print mixed source+assembly.
2854 * Process record and replay
2856 In a architecture environment that supports ``process record and
2857 replay'', ``process record and replay'' target can record a log of
2858 the process execution, and replay it with both forward and reverse
2861 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2862 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2863 set execution-direction {forward|reverse}, for targets that support
2866 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2867 feature is available with a native GDB running on kernel version
2870 * GDB now has support for multi-byte and wide character sets on the
2871 target. Strings whose character type is wchar_t, char16_t, or
2872 char32_t are now correctly printed. GDB supports wide- and unicode-
2873 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2874 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2875 `printf'. This feature requires iconv to work properly; if your
2876 system does not have a working iconv, GDB can use GNU libiconv. See
2877 the installation instructions for more information.
2879 * GDB now supports automatic retrieval of shared library files from
2880 remote targets. To use this feature, specify a system root that begins
2881 with the `remote:' prefix, either via the `set sysroot' command or via
2882 the `--with-sysroot' configure-time option.
2884 * "info sharedlibrary" now takes an optional regex of libraries to show,
2885 and it now reports if a shared library has no debugging information.
2887 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2888 now complete on file names.
2890 * When completing in expressions, gdb will attempt to limit
2891 completions to allowable structure or union fields, where appropriate.
2892 For instance, consider:
2894 # struct example { int f1; double f2; };
2895 # struct example variable;
2898 If the user types TAB at the end of this command line, the available
2899 completions will be "f1" and "f2".
2901 * Inlined functions are now supported. They show up in backtraces, and
2902 the "step", "next", and "finish" commands handle them automatically.
2904 * GDB now supports the token-splicing (##) and stringification (#)
2905 operators when expanding macros. It also supports variable-arity
2908 * GDB now supports inspecting extra signal information, exported by
2909 the new $_siginfo convenience variable. The feature is currently
2910 implemented on linux ARM, i386 and amd64.
2912 * GDB can now display the VFP floating point registers and NEON vector
2913 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2914 can provide these registers (requires Linux 2.6.30 or later). Remote
2915 and simulator targets may also provide them.
2917 * New remote packets
2920 Search memory for a sequence of bytes.
2923 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2924 operation over reliable transport links. Use of this packet is
2925 controlled by the `set remote noack-packet' command.
2928 Kill the process with the specified process ID. Use this in preference
2929 to `k' when multiprocess protocol extensions are supported.
2932 Obtains additional operating system information
2936 Read or write additional signal information.
2938 * Removed remote protocol undocumented extension
2940 An undocumented extension to the remote protocol's `S' stop reply
2941 packet that permited the stub to pass a process id was removed.
2942 Remote servers should use the `T' stop reply packet instead.
2944 * GDB now supports multiple function calling conventions according to the
2945 DWARF-2 DW_AT_calling_convention function attribute.
2947 * The SH target utilizes the aforementioned change to distinguish between gcc
2948 and Renesas calling convention. It also adds the new CLI commands
2949 `set/show sh calling-convention'.
2951 * GDB can now read compressed debug sections, as produced by GNU gold
2952 with the --compress-debug-sections=zlib flag.
2954 * 64-bit core files are now supported on AIX.
2956 * Thread switching is now supported on Tru64.
2958 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2959 which will be allocated using malloc later in program execution.
2961 * The qXfer:libraries:read remote procotol packet now allows passing a
2962 list of section offsets.
2964 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2965 conditions handling signals delivered during attach or thread creation
2966 have also been fixed.
2968 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2969 From the user's standpoint, all unqualified instances of True and False
2970 are treated as the standard definitions, regardless of context.
2972 * GDB now parses C++ symbol and type names more flexibly. For
2975 template<typename T> class C { };
2978 GDB will now correctly handle all of:
2980 ptype C<char const *>
2981 ptype C<char const*>
2982 ptype C<const char *>
2983 ptype C<const char*>
2985 * New features in the GDB remote stub, gdbserver
2987 - The "--wrapper" command-line argument tells gdbserver to use a
2988 wrapper program to launch programs for debugging.
2990 - On PowerPC and S/390 targets, it is now possible to use a single
2991 gdbserver executable to debug both 32-bit and 64-bit programs.
2992 (This requires gdbserver itself to be built as a 64-bit executable.)
2994 - gdbserver uses the new noack protocol mode for TCP connections to
2995 reduce communications latency, if also supported and enabled in GDB.
2997 - Support for the sparc64-linux-gnu target is now included in
3000 - The amd64-linux build of gdbserver now supports debugging both
3001 32-bit and 64-bit programs.
3003 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3004 now support hardware watchpoints, and will use them automatically
3009 GDB now has support for scripting using Python. Whether this is
3010 available is determined at configure time.
3012 New GDB commands can now be written in Python.
3014 * Ada tasking support
3016 Ada tasks can now be inspected in GDB. The following commands have
3020 Print the list of Ada tasks.
3022 Print detailed information about task number N.
3024 Print the task number of the current task.
3026 Switch the context of debugging to task number N.
3028 * Support for user-defined prefixed commands. The "define" command can
3029 add new commands to existing prefixes, e.g. "target".
3031 * Multi-inferior, multi-process debugging.
3033 GDB now has generalized support for multi-inferior debugging. See
3034 "Debugging Multiple Inferiors" in the manual for more information.
3035 Although availability still depends on target support, the command
3036 set is more uniform now. The GNU/Linux specific multi-forks support
3037 has been migrated to this new framework. This implied some user
3038 visible changes; see "New commands" and also "Removed commands"
3041 * Target descriptions can now describe the target OS ABI. See the
3042 "Target Description Format" section in the user manual for more
3045 * Target descriptions can now describe "compatible" architectures
3046 to indicate that the target can execute applications for a different
3047 architecture in addition to those for the main target architecture.
3048 See the "Target Description Format" section in the user manual for
3051 * Multi-architecture debugging.
3053 GDB now includes general supports for debugging applications on
3054 hybrid systems that use more than one single processor architecture
3055 at the same time. Each such hybrid architecture still requires
3056 specific support to be added. The only hybrid architecture supported
3057 in this version of GDB is the Cell Broadband Engine.
3059 * GDB now supports integrated debugging of Cell/B.E. applications that
3060 use both the PPU and SPU architectures. To enable support for hybrid
3061 Cell/B.E. debugging, you need to configure GDB to support both the
3062 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3063 --enable-targets configure option.
3065 * Non-stop mode debugging.
3067 For some targets, GDB now supports an optional mode of operation in
3068 which you can examine stopped threads while other threads continue
3069 to execute freely. This is referred to as non-stop mode, with the
3070 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3071 section in the user manual for more information.
3073 To be able to support remote non-stop debugging, a remote stub needs
3074 to implement the non-stop mode remote protocol extensions, as
3075 described in the "Remote Non-Stop" section of the user manual. The
3076 GDB remote stub, gdbserver, has been adjusted to support these
3077 extensions on linux targets.
3079 * New commands (for set/show, see "New options" below)
3081 catch syscall [NAME(S) | NUMBER(S)]
3082 Catch system calls. Arguments, which should be names of system
3083 calls or their numbers, mean catch only those syscalls. Without
3084 arguments, every syscall will be caught. When the inferior issues
3085 any of the specified syscalls, GDB will stop and announce the system
3086 call, both when it is called and when its call returns. This
3087 feature is currently available with a native GDB running on the
3088 Linux Kernel, under the following architectures: x86, x86_64,
3089 PowerPC and PowerPC64.
3091 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3093 Search memory for a sequence of bytes.
3095 maint set python print-stack
3096 maint show python print-stack
3097 Show a stack trace when an error is encountered in a Python script.
3100 Invoke CODE by passing it to the Python interpreter.
3105 These allow macros to be defined, undefined, and listed
3109 Show operating system information about processes.
3112 List the inferiors currently under GDB's control.
3115 Switch focus to inferior number NUM.
3118 Detach from inferior number NUM.
3121 Kill inferior number NUM.
3125 set spu stop-on-load
3126 show spu stop-on-load
3127 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3129 set spu auto-flush-cache
3130 show spu auto-flush-cache
3131 Control whether to automatically flush the software-managed cache
3132 during Cell/B.E. debugging.
3134 set sh calling-convention
3135 show sh calling-convention
3136 Control the calling convention used when calling SH target functions.
3139 show debug timestamp
3140 Control display of timestamps with GDB debugging output.
3142 set disassemble-next-line
3143 show disassemble-next-line
3144 Control display of disassembled source lines or instructions when
3147 set remote noack-packet
3148 show remote noack-packet
3149 Set/show the use of remote protocol QStartNoAckMode packet. See above
3150 under "New remote packets."
3152 set remote query-attached-packet
3153 show remote query-attached-packet
3154 Control use of remote protocol `qAttached' (query-attached) packet.
3156 set remote read-siginfo-object
3157 show remote read-siginfo-object
3158 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3161 set remote write-siginfo-object
3162 show remote write-siginfo-object
3163 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3166 set remote reverse-continue
3167 show remote reverse-continue
3168 Control use of remote protocol 'bc' (reverse-continue) packet.
3170 set remote reverse-step
3171 show remote reverse-step
3172 Control use of remote protocol 'bs' (reverse-step) packet.
3174 set displaced-stepping
3175 show displaced-stepping
3176 Control displaced stepping mode. Displaced stepping is a way to
3177 single-step over breakpoints without removing them from the debuggee.
3178 Also known as "out-of-line single-stepping".
3181 show debug displaced
3182 Control display of debugging info for displaced stepping.
3184 maint set internal-error
3185 maint show internal-error
3186 Control what GDB does when an internal error is detected.
3188 maint set internal-warning
3189 maint show internal-warning
3190 Control what GDB does when an internal warning is detected.
3195 Use a wrapper program to launch programs for debugging.
3197 set multiple-symbols (all|ask|cancel)
3198 show multiple-symbols
3199 The value of this variable can be changed to adjust the debugger behavior
3200 when an expression or a breakpoint location contains an ambiguous symbol
3201 name (an overloaded function name, for instance).
3203 set breakpoint always-inserted
3204 show breakpoint always-inserted
3205 Keep breakpoints always inserted in the target, as opposed to inserting
3206 them when resuming the target, and removing them when the target stops.
3207 This option can improve debugger performance on slow remote targets.
3209 set arm fallback-mode (arm|thumb|auto)
3210 show arm fallback-mode
3211 set arm force-mode (arm|thumb|auto)
3213 These commands control how ARM GDB determines whether instructions
3214 are ARM or Thumb. The default for both settings is auto, which uses
3215 the current CPSR value for instructions without symbols; previous
3216 versions of GDB behaved as if "set arm fallback-mode arm".
3218 set disable-randomization
3219 show disable-randomization
3220 Standalone programs run with the virtual address space randomization enabled
3221 by default on some platforms. This option keeps the addresses stable across
3222 multiple debugging sessions.
3226 Control whether other threads are stopped or not when some thread hits
3231 Requests that asynchronous execution is enabled in the target, if available.
3232 In this case, it's possible to resume target in the background, and interact
3233 with GDB while the target is running. "show target-async" displays the
3234 current state of asynchronous execution of the target.
3236 set target-wide-charset
3237 show target-wide-charset
3238 The target-wide-charset is the name of the character set that GDB
3239 uses when printing characters whose type is wchar_t.
3241 set tcp auto-retry (on|off)
3243 set tcp connect-timeout
3244 show tcp connect-timeout
3245 These commands allow GDB to retry failed TCP connections to a remote stub
3246 with a specified timeout period; this is useful if the stub is launched
3247 in parallel with GDB but may not be ready to accept connections immediately.
3249 set libthread-db-search-path
3250 show libthread-db-search-path
3251 Control list of directories which GDB will search for appropriate
3254 set schedule-multiple (on|off)
3255 show schedule-multiple
3256 Allow GDB to resume all threads of all processes or only threads of
3257 the current process.
3261 Use more aggressive caching for accesses to the stack. This improves
3262 performance of remote debugging (particularly backtraces) without
3263 affecting correctness.
3265 set interactive-mode (on|off|auto)
3266 show interactive-mode
3267 Control whether GDB runs in interactive mode (on) or not (off).
3268 When in interactive mode, GDB waits for the user to answer all
3269 queries. Otherwise, GDB does not wait and assumes the default
3270 answer. When set to auto (the default), GDB determines which
3271 mode to use based on the stdin settings.
3276 For program forks, this is replaced by the new more generic `info
3277 inferiors' command. To list checkpoints, you can still use the
3278 `info checkpoints' command, which was an alias for the `info forks'
3282 Replaced by the new `inferior' command. To switch between
3283 checkpoints, you can still use the `restart' command, which was an
3284 alias for the `fork' command.
3287 This is removed, since some targets don't have a notion of
3288 processes. To switch between processes, you can still use the
3289 `inferior' command using GDB's own inferior number.
3292 For program forks, this is replaced by the new more generic `kill
3293 inferior' command. To delete a checkpoint, you can still use the
3294 `delete checkpoint' command, which was an alias for the `delete
3298 For program forks, this is replaced by the new more generic `detach
3299 inferior' command. To detach a checkpoint, you can still use the
3300 `detach checkpoint' command, which was an alias for the `detach
3303 * New native configurations
3305 x86/x86_64 Darwin i[34567]86-*-darwin*
3307 x86_64 MinGW x86_64-*-mingw*
3311 Lattice Mico32 lm32-*
3312 x86 DICOS i[34567]86-*-dicos*
3313 x86_64 DICOS x86_64-*-dicos*
3316 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3317 (mingw32ce) debugging.
3323 These commands were actually not implemented on any target.
3325 *** Changes in GDB 6.8
3327 * New native configurations
3329 NetBSD/hppa hppa*-*netbsd*
3330 Xtensa GNU/Linux xtensa*-*-linux*
3334 NetBSD/hppa hppa*-*-netbsd*
3335 Xtensa GNU/Lunux xtensa*-*-linux*
3337 * Change in command line behavior -- corefiles vs. process ids.
3339 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3340 attaching to process NUMBER fails, GDB no longer attempts to open a
3341 core file named NUMBER. Attaching to a program using the -c option
3342 is no longer supported. Instead, use the '-p' or '--pid' options.
3344 * GDB can now be built as a native debugger for debugging Windows x86
3345 (mingw32) Portable Executable (PE) programs.
3347 * Pending breakpoints no longer change their number when their address
3350 * GDB now supports breakpoints with multiple locations,
3351 including breakpoints on C++ constructors, inside C++ templates,
3352 and in inlined functions.
3354 * GDB's ability to debug optimized code has been improved. GDB more
3355 accurately identifies function bodies and lexical blocks that occupy
3356 more than one contiguous range of addresses.
3358 * Target descriptions can now describe registers for PowerPC.
3360 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3361 registers on PowerPC targets.
3363 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3364 targets even when the libthread_db library is not available.
3366 * The GDB remote stub, gdbserver, now supports the new file transfer
3367 commands (remote put, remote get, and remote delete).
3369 * The GDB remote stub, gdbserver, now supports run and attach in
3370 extended-remote mode.
3372 * hppa*64*-*-hpux11* target broken
3373 The debugger is unable to start a program and fails with the following
3374 error: "Error trying to get information about dynamic linker".
3375 The gdb-6.7 release is also affected.
3377 * GDB now supports the --enable-targets= configure option to allow
3378 building a single GDB executable that supports multiple remote
3379 target architectures.
3381 * GDB now supports debugging C and C++ programs which use the
3382 Decimal Floating Point extension. In addition, the PowerPC target
3383 now has a set of pseudo-registers to inspect decimal float values
3384 stored in two consecutive float registers.
3386 * The -break-insert MI command can optionally create pending
3389 * Improved support for debugging Ada
3390 Many improvements to the Ada language support have been made. These
3392 - Better support for Ada2005 interface types
3393 - Improved handling of arrays and slices in general
3394 - Better support for Taft-amendment types
3395 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3397 - Improved command completion in Ada
3400 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3405 set print frame-arguments (all|scalars|none)
3406 show print frame-arguments
3407 The value of this variable can be changed to control which argument
3408 values should be printed by the debugger when displaying a frame.
3413 Transfer files to and from a remote target, and delete remote files.
3420 Transfer files to and from a remote target, and delete remote files.
3422 * New remote packets
3429 Open, close, read, write, and delete files on the remote system.
3432 Attach to an existing process on the remote system, in extended-remote
3436 Run a new process on the remote system, in extended-remote mode.
3438 *** Changes in GDB 6.7
3440 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3441 bfd, libiberty and opcodes, as revealed by static analysis donated by
3442 Coverity, Inc. (http://scan.coverity.com).
3444 * When looking up multiply-defined global symbols, GDB will now prefer the
3445 symbol definition in the current shared library if it was built using the
3446 -Bsymbolic linker option.
3448 * When the Text User Interface (TUI) is not configured, GDB will now
3449 recognize the -tui command-line option and print a message that the TUI
3452 * The GDB remote stub, gdbserver, now has lower overhead for high
3453 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3455 * GDB for MIPS targets now autodetects whether a remote target provides
3456 32-bit or 64-bit register values.
3458 * Support for C++ member pointers has been improved.
3460 * GDB now understands XML target descriptions, which specify the
3461 target's overall architecture. GDB can read a description from
3462 a local file or over the remote serial protocol.
3464 * Vectors of single-byte data use a new integer type which is not
3465 automatically displayed as character or string data.
3467 * The /s format now works with the print command. It displays
3468 arrays of single-byte integers and pointers to single-byte integers
3471 * Target descriptions can now describe target-specific registers,
3472 for architectures which have implemented the support (currently
3473 only ARM, M68K, and MIPS).
3475 * GDB and the GDB remote stub, gdbserver, now support the XScale
3478 * The GDB remote stub, gdbserver, has been updated to support
3479 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3480 has been rewritten to use the standard GDB remote protocol.
3482 * GDB can now step into C++ functions which are called through thunks.
3484 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3486 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3487 layout. It also supports a TextSeg= and DataSeg= response when only
3488 segment base addresses (rather than offsets) are available.
3490 * The /i format now outputs any trailing branch delay slot instructions
3491 immediately following the last instruction within the count specified.
3493 * The GDB remote protocol "T" stop reply packet now supports a
3494 "library" response. Combined with the new "qXfer:libraries:read"
3495 packet, this response allows GDB to debug shared libraries on targets
3496 where the operating system manages the list of loaded libraries (e.g.
3497 Windows and SymbianOS).
3499 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3500 (DLLs) on Windows and Windows CE targets.
3502 * GDB now supports a faster verification that a .debug file matches its binary
3503 according to its build-id signature, if the signature is present.
3509 Enable or disable hardware flow control (RTS/CTS) on the serial port
3510 when debugging using remote targets.
3512 set mem inaccessible-by-default
3513 show mem inaccessible-by-default
3514 If the target supplies a memory map, for instance via the remote
3515 protocol's "qXfer:memory-map:read" packet, setting this variable
3516 prevents GDB from accessing memory outside the memory map. This
3517 is useful for targets with memory mapped registers or which react
3518 badly to accesses of unmapped address space.
3520 set breakpoint auto-hw
3521 show breakpoint auto-hw
3522 If the target supplies a memory map, for instance via the remote
3523 protocol's "qXfer:memory-map:read" packet, setting this variable
3524 lets GDB use hardware breakpoints automatically for memory regions
3525 where it can not use software breakpoints. This covers both the
3526 "break" command and internal breakpoints used for other commands
3527 including "next" and "finish".
3530 catch exception unhandled
3531 Stop the program execution when Ada exceptions are raised.
3534 Stop the program execution when an Ada assertion failed.
3538 Set an alternate system root for target files. This is a more
3539 general version of "set solib-absolute-prefix", which is now
3540 an alias to "set sysroot".
3543 Provide extended SPU facility status information. This set of
3544 commands is available only when debugging the Cell/B.E. SPU
3547 * New native configurations
3549 OpenBSD/sh sh*-*openbsd*
3552 unset tdesc filename
3554 Use the specified local file as an XML target description, and do
3555 not query the target for its built-in description.
3559 OpenBSD/sh sh*-*-openbsd*
3560 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3561 Toshiba Media Processor mep-elf
3563 * New remote packets
3566 Ignore the specified signals; pass them directly to the debugged program
3567 without stopping other threads or reporting them to GDB.
3569 qXfer:features:read:
3570 Read an XML target description from the target, which describes its
3575 Read or write contents of an spufs file on the target system. These
3576 packets are available only on the Cell/B.E. SPU architecture.
3578 qXfer:libraries:read:
3579 Report the loaded shared libraries. Combined with new "T" packet
3580 response, this packet allows GDB to debug shared libraries on
3581 targets where the operating system manages the list of loaded
3582 libraries (e.g. Windows and SymbianOS).
3586 Support for these obsolete configurations has been removed.
3594 i[34567]86-*-lynxos*
3595 i[34567]86-*-netware*
3596 i[34567]86-*-sco3.2v5*
3597 i[34567]86-*-sco3.2v4*
3599 i[34567]86-*-sysv4.2*
3602 i[34567]86-*-unixware2*
3603 i[34567]86-*-unixware*
3612 * Other removed features
3619 Various m68k-only ROM monitors.
3626 Various Renesas ROM monitors and debugging interfaces for SH and
3631 Support for a Macraigor serial interface to on-chip debugging.
3632 GDB does not directly support the newer parallel or USB
3637 A debug information format. The predecessor to DWARF 2 and
3638 DWARF 3, which are still supported.
3640 Support for the HP aCC compiler on HP-UX/PA-RISC
3642 SOM-encapsulated symbolic debugging information, automatic
3643 invocation of pxdb, and the aCC custom C++ ABI. This does not
3644 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3645 with aCC can still be debugged on an assembly level.
3647 MIPS ".pdr" sections
3649 A MIPS-specific format used to describe stack frame layout
3650 in debugging information.
3654 GDB could work with an older version of Guile to debug
3655 the interpreter and Scheme programs running in it.
3657 set mips stack-arg-size
3658 set mips saved-gpreg-size
3660 Use "set mips abi" to control parameter passing for MIPS.
3662 *** Changes in GDB 6.6
3667 Cell Broadband Engine SPU spu-elf
3669 * GDB can now be configured as a cross-debugger targeting native Windows
3670 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3671 running on a Windows system over TCP/IP to debug Windows programs.
3673 * The GDB remote stub, gdbserver, has been updated to support Windows and
3674 Cygwin debugging. Both single-threaded and multi-threaded programs are
3677 * The "set trust-readonly-sections" command works again. This command was
3678 broken in GDB 6.3, 6.4, and 6.5.
3680 * The "load" command now supports writing to flash memory, if the remote
3681 stub provides the required support.
3683 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3684 longer requires symbolic debug information (e.g. DWARF-2).
3689 unset substitute-path
3690 show substitute-path
3691 Manage a list of substitution rules that GDB uses to rewrite the name
3692 of the directories where the sources are located. This can be useful
3693 for instance when the sources were moved to a different location
3694 between compilation and debugging.
3698 Print each CLI command as it is executed. Each command is prefixed with
3699 a number of `+' symbols representing the nesting depth.
3700 The source command now has a `-v' option to enable the same feature.
3704 The ARM Demon monitor support (RDP protocol, "target rdp").
3706 Kernel Object Display, an embedded debugging feature which only worked with
3707 an obsolete version of Cisco IOS.
3709 The 'set download-write-size' and 'show download-write-size' commands.
3711 * New remote packets
3714 Tell a stub about GDB client features, and request remote target features.
3715 The first feature implemented is PacketSize, which allows the target to
3716 specify the size of packets it can handle - to minimize the number of
3717 packets required and improve performance when connected to a remote
3721 Fetch an OS auxilliary vector from the remote stub. This packet is a
3722 more efficient replacement for qPart:auxv:read.
3724 qXfer:memory-map:read:
3725 Fetch a memory map from the remote stub, including information about
3726 RAM, ROM, and flash memory devices.
3731 Erase and program a flash memory device.
3733 * Removed remote packets
3736 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3737 used it, and only gdbserver implemented it.
3739 *** Changes in GDB 6.5
3743 Renesas M32C/M16C m32c-elf
3745 Morpho Technologies ms1 ms1-elf
3749 init-if-undefined Initialize a convenience variable, but
3750 only if it doesn't already have a value.
3752 The following commands are presently only implemented for native GNU/Linux:
3754 checkpoint Save a snapshot of the program state.
3756 restart <n> Return the program state to a
3757 previously saved state.
3759 info checkpoints List currently saved checkpoints.
3761 delete-checkpoint <n> Delete a previously saved checkpoint.
3763 set|show detach-on-fork Tell gdb whether to detach from a newly
3764 forked process, or to keep debugging it.
3766 info forks List forks of the user program that
3767 are available to be debugged.
3769 fork <n> Switch to debugging one of several
3770 forks of the user program that are
3771 available to be debugged.
3773 delete-fork <n> Delete a fork from the list of forks
3774 that are available to be debugged (and
3775 kill the forked process).
3777 detach-fork <n> Delete a fork from the list of forks
3778 that are available to be debugged (and
3779 allow the process to continue).
3783 Morpho Technologies ms2 ms1-elf
3785 * Improved Windows host support
3787 GDB now builds as a cross debugger hosted on i686-mingw32, including
3788 native console support, and remote communications using either
3789 network sockets or serial ports.
3791 * Improved Modula-2 language support
3793 GDB can now print most types in the Modula-2 syntax. This includes:
3794 basic types, set types, record types, enumerated types, range types,
3795 pointer types and ARRAY types. Procedure var parameters are correctly
3796 printed and hexadecimal addresses and character constants are also
3797 written in the Modula-2 syntax. Best results can be obtained by using
3798 GNU Modula-2 together with the -gdwarf-2 command line option.
3802 The ARM rdi-share module.
3804 The Netware NLM debug server.
3806 *** Changes in GDB 6.4
3808 * New native configurations
3810 OpenBSD/arm arm*-*-openbsd*
3811 OpenBSD/mips64 mips64-*-openbsd*
3815 Morpho Technologies ms1 ms1-elf
3817 * New command line options
3819 --batch-silent As for --batch, but totally silent.
3820 --return-child-result The debugger will exist with the same value
3821 the child (debugged) program exited with.
3822 --eval-command COMMAND, -ex COMMAND
3823 Execute a single GDB CLI command. This may be
3824 specified multiple times and in conjunction
3825 with the --command (-x) option.
3827 * Deprecated commands removed
3829 The following commands, that were deprecated in 2000, have been
3833 set|show arm disassembly-flavor set|show arm disassembler
3834 othernames set arm disassembler
3835 set|show remotedebug set|show debug remote
3836 set|show archdebug set|show debug arch
3837 set|show eventdebug set|show debug event
3840 * New BSD user-level threads support
3842 It is now possible to debug programs using the user-level threads
3843 library on OpenBSD and FreeBSD. Currently supported (target)
3846 FreeBSD/amd64 x86_64-*-freebsd*
3847 FreeBSD/i386 i386-*-freebsd*
3848 OpenBSD/i386 i386-*-openbsd*
3850 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3851 are not yet supported.
3853 * New support for Matsushita MN10300 w/sim added
3854 (Work in progress). mn10300-elf.
3856 * REMOVED configurations and files
3858 VxWorks and the XDR protocol *-*-vxworks
3859 Motorola MCORE mcore-*-*
3860 National Semiconductor NS32000 ns32k-*-*
3862 * New "set print array-indexes" command
3864 After turning this setting "on", GDB prints the index of each element
3865 when displaying arrays. The default is "off" to preserve the previous
3868 * VAX floating point support
3870 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3872 * User-defined command support
3874 In addition to using $arg0..$arg9 for argument passing, it is now possible
3875 to use $argc to determine now many arguments have been passed. See the
3876 section on user-defined commands in the user manual for more information.
3878 *** Changes in GDB 6.3:
3880 * New command line option
3882 GDB now accepts -l followed by a number to set the timeout for remote
3885 * GDB works with GCC -feliminate-dwarf2-dups
3887 GDB now supports a more compact representation of DWARF-2 debug
3888 information using DW_FORM_ref_addr references. These are produced
3889 by GCC with the option -feliminate-dwarf2-dups and also by some
3890 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3891 to use -feliminate-dwarf2-dups.
3893 * Internationalization
3895 When supported by the host system, GDB will be built with
3896 internationalization (libintl). The task of marking up the sources is
3897 continued, we're looking forward to our first translation.
3901 Initial support for debugging programs compiled with the GNAT
3902 implementation of the Ada programming language has been integrated
3903 into GDB. In this release, support is limited to expression evaluation.
3905 * New native configurations
3907 GNU/Linux/m32r m32r-*-linux-gnu
3911 GDB's remote protocol now includes support for the 'p' packet. This
3912 packet is used to fetch individual registers from a remote inferior.
3914 * END-OF-LIFE registers[] compatibility module
3916 GDB's internal register infrastructure has been completely rewritten.
3917 The new infrastructure making possible the implementation of key new
3918 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3921 GDB 6.3 will be the last release to include the the registers[]
3922 compatibility module that allowed out-of-date configurations to
3923 continue to work. This change directly impacts the following
3933 powerpc bdm protocol
3935 Unless there is activity to revive these configurations, they will be
3936 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3938 * OBSOLETE configurations and files
3940 Configurations that have been declared obsolete in this release have
3941 been commented out. Unless there is activity to revive these
3942 configurations, the next release of GDB will have their sources
3943 permanently REMOVED.
3952 *** Changes in GDB 6.2.1:
3954 * MIPS `break main; run' gave an heuristic-fence-post warning
3956 When attempting to run even a simple program, a warning about
3957 heuristic-fence-post being hit would be reported. This problem has
3960 * MIPS IRIX 'long double' crashed GDB
3962 When examining a long double variable, GDB would get a segmentation
3963 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3964 IRIX long double values).
3968 A bug in the VAX stack code was causing problems with the "next"
3969 command. This problem has been fixed.
3971 *** Changes in GDB 6.2:
3973 * Fix for ``many threads''
3975 On GNU/Linux systems that use the NPTL threads library, a program
3976 rapidly creating and deleting threads would confuse GDB leading to the
3979 ptrace: No such process.
3980 thread_db_get_info: cannot get thread info: generic error
3982 This problem has been fixed.
3984 * "-async" and "-noasync" options removed.
3986 Support for the broken "-noasync" option has been removed (it caused
3989 * New ``start'' command.
3991 This command runs the program until the begining of the main procedure.
3993 * New BSD Kernel Data Access Library (libkvm) interface
3995 Using ``target kvm'' it is now possible to debug kernel core dumps and
3996 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3997 platforms. Currently supported (native-only) configurations are:
3999 FreeBSD/amd64 x86_64-*-freebsd*
4000 FreeBSD/i386 i?86-*-freebsd*
4001 NetBSD/i386 i?86-*-netbsd*
4002 NetBSD/m68k m68*-*-netbsd*
4003 NetBSD/sparc sparc-*-netbsd*
4004 OpenBSD/amd64 x86_64-*-openbsd*
4005 OpenBSD/i386 i?86-*-openbsd*
4006 OpenBSD/m68k m68*-openbsd*
4007 OpenBSD/sparc sparc-*-openbsd*
4009 * Signal trampoline code overhauled
4011 Many generic problems with GDB's signal handling code have been fixed.
4012 These include: backtraces through non-contiguous stacks; recognition
4013 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4014 call; backtrace through a signal trampoline; step into and out of
4015 signal handlers; and single-stepping in the signal trampoline.
4017 Please note that kernel bugs are a limiting factor here. These
4018 features have been shown to work on an s390 GNU/Linux system that
4019 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4021 * Cygwin support for DWARF 2 added.
4023 * New native configurations
4025 GNU/Linux/hppa hppa*-*-linux*
4026 OpenBSD/hppa hppa*-*-openbsd*
4027 OpenBSD/m68k m68*-*-openbsd*
4028 OpenBSD/m88k m88*-*-openbsd*
4029 OpenBSD/powerpc powerpc-*-openbsd*
4030 NetBSD/vax vax-*-netbsd*
4031 OpenBSD/vax vax-*-openbsd*
4033 * END-OF-LIFE frame compatibility module
4035 GDB's internal frame infrastructure has been completely rewritten.
4036 The new infrastructure making it possible to support key new features
4037 including DWARF 2 Call Frame Information. To aid in the task of
4038 migrating old configurations to this new infrastructure, a
4039 compatibility module, that allowed old configurations to continue to
4040 work, was also included.
4042 GDB 6.2 will be the last release to include this frame compatibility
4043 module. This change directly impacts the following configurations:
4053 Unless there is activity to revive these configurations, they will be
4054 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4056 * REMOVED configurations and files
4058 Sun 3, running SunOS 3 m68*-*-sunos3*
4059 Sun 3, running SunOS 4 m68*-*-sunos4*
4060 Sun 2, running SunOS 3 m68000-*-sunos3*
4061 Sun 2, running SunOS 4 m68000-*-sunos4*
4062 Motorola 680x0 running LynxOS m68*-*-lynxos*
4063 AT&T 3b1/Unix pc m68*-att-*
4064 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4065 decstation mips-dec-* mips-little-*
4066 riscos mips-*-riscos* mips-*-sysv*
4067 sonymips mips-sony-*
4068 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4070 *** Changes in GDB 6.1.1:
4072 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4074 The TUI (Text-mode User Interface) is now built as part of a default
4075 GDB configuration. It is enabled by either selecting the TUI with the
4076 command line option "-i=tui" or by running the separate "gdbtui"
4077 program. For more information on the TUI, see the manual "Debugging
4080 * Pending breakpoint support (also included in GDB 6.1)
4082 Support has been added to allow you to specify breakpoints in shared
4083 libraries that have not yet been loaded. If a breakpoint location
4084 cannot be found, and the "breakpoint pending" option is set to auto,
4085 GDB queries you if you wish to make the breakpoint pending on a future
4086 shared-library load. If and when GDB resolves the breakpoint symbol,
4087 the pending breakpoint is removed as one or more regular breakpoints
4090 Pending breakpoints are very useful for GCJ Java debugging.
4092 * Fixed ISO-C build problems
4094 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4095 non ISO-C code that stopped them being built using a more strict ISO-C
4096 compiler (e.g., IBM's C compiler).
4098 * Fixed build problem on IRIX 5
4100 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4101 wasn't able to compile compile on an IRIX 5 system.
4103 * Added execute permission to gdb/gdbserver/configure
4105 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4106 permission. This bug would cause configure to fail on a number of
4107 systems (Solaris, IRIX). Ref: server/519.
4109 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4111 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4112 has been updated to use constant array sizes.
4114 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4116 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4117 its generated DWARF Call Frame Info. This encoding was causing GDB to
4118 panic, that panic has been fixed. Ref: gdb/1628.
4120 * Fixed a problem when examining parameters in shared library code.
4122 When examining parameters in optimized shared library code generated
4123 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4124 not available''. GDB now correctly displays the variable's value.
4126 *** Changes in GDB 6.1:
4128 * Removed --with-mmalloc
4130 Support for the mmalloc memory manager has been removed, as it
4131 conflicted with the internal gdb byte cache.
4133 * Changes in AMD64 configurations
4135 The AMD64 target now includes the %cs and %ss registers. As a result
4136 the AMD64 remote protocol has changed; this affects the floating-point
4137 and SSE registers. If you rely on those registers for your debugging,
4138 you should upgrade gdbserver on the remote side.
4140 * Revised SPARC target
4142 The SPARC target has been completely revised, incorporating the
4143 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4144 support for LynxOS and SunOS 4 has been dropped. Calling functions
4145 from within GDB on operating systems with a non-executable stack
4146 (Solaris, OpenBSD) now works.
4150 GDB has a new C++ demangler which does a better job on the mangled
4151 names generated by current versions of g++. It also runs faster, so
4152 with this and other changes gdb should now start faster on large C++
4155 * DWARF 2 Location Expressions
4157 GDB support for location expressions has been extended to support function
4158 arguments and frame bases. Older versions of GDB could crash when they
4161 * C++ nested types and namespaces
4163 GDB's support for nested types and namespaces in C++ has been
4164 improved, especially if you use the DWARF 2 debugging format. (This
4165 is the default for recent versions of GCC on most platforms.)
4166 Specifically, if you have a class "Inner" defined within a class or
4167 namespace "Outer", then GDB realizes that the class's name is
4168 "Outer::Inner", not simply "Inner". This should greatly reduce the
4169 frequency of complaints about not finding RTTI symbols. In addition,
4170 if you are stopped at inside of a function defined within a namespace,
4171 GDB modifies its name lookup accordingly.
4173 * New native configurations
4175 NetBSD/amd64 x86_64-*-netbsd*
4176 OpenBSD/amd64 x86_64-*-openbsd*
4177 OpenBSD/alpha alpha*-*-openbsd*
4178 OpenBSD/sparc sparc-*-openbsd*
4179 OpenBSD/sparc64 sparc64-*-openbsd*
4181 * New debugging protocols
4183 M32R with SDI protocol m32r-*-elf*
4185 * "set prompt-escape-char" command deleted.
4187 The command "set prompt-escape-char" has been deleted. This command,
4188 and its very obscure effet on GDB's prompt, was never documented,
4189 tested, nor mentioned in the NEWS file.
4191 * OBSOLETE configurations and files
4193 Configurations that have been declared obsolete in this release have
4194 been commented out. Unless there is activity to revive these
4195 configurations, the next release of GDB will have their sources
4196 permanently REMOVED.
4198 Sun 3, running SunOS 3 m68*-*-sunos3*
4199 Sun 3, running SunOS 4 m68*-*-sunos4*
4200 Sun 2, running SunOS 3 m68000-*-sunos3*
4201 Sun 2, running SunOS 4 m68000-*-sunos4*
4202 Motorola 680x0 running LynxOS m68*-*-lynxos*
4203 AT&T 3b1/Unix pc m68*-att-*
4204 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4205 decstation mips-dec-* mips-little-*
4206 riscos mips-*-riscos* mips-*-sysv*
4207 sonymips mips-sony-*
4208 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4210 * REMOVED configurations and files
4212 SGI Irix-4.x mips-sgi-irix4 or iris4
4213 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4214 Z8000 simulator z8k-zilog-none or z8ksim
4215 Matsushita MN10200 w/simulator mn10200-*-*
4216 H8/500 simulator h8500-hitachi-hms or h8500hms
4217 HP/PA running BSD hppa*-*-bsd*
4218 HP/PA running OSF/1 hppa*-*-osf*
4219 HP/PA Pro target hppa*-*-pro*
4220 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4221 386BSD i[3456]86-*-bsd*
4222 Sequent family i[3456]86-sequent-sysv4*
4223 i[3456]86-sequent-sysv*
4224 i[3456]86-sequent-bsd*
4225 SPARC running LynxOS sparc-*-lynxos*
4226 SPARC running SunOS 4 sparc-*-sunos4*
4227 Tsqware Sparclet sparclet-*-*
4228 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4230 *** Changes in GDB 6.0:
4234 Support for debugging the Objective-C programming language has been
4235 integrated into GDB.
4237 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4239 DWARF 2's Call Frame Information makes available compiler generated
4240 information that more exactly describes the program's run-time stack.
4241 By using this information, GDB is able to provide more robust stack
4244 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4245 have been updated to use a new backtrace mechanism which includes
4246 DWARF 2 CFI support.
4250 GDB's remote protocol has been extended to include support for hosted
4251 file I/O (where the remote target uses GDB's file system). See GDB's
4252 remote protocol documentation for details.
4254 * All targets using the new architecture framework.
4256 All of GDB's targets have been updated to use the new internal
4257 architecture framework. The way is now open for future GDB releases
4258 to include cross-architecture native debugging support (i386 on amd64,
4261 * GNU/Linux's Thread Local Storage (TLS)
4263 GDB now includes support for for the GNU/Linux implementation of
4264 per-thread variables.
4266 * GNU/Linux's Native POSIX Thread Library (NPTL)
4268 GDB's thread code has been updated to work with either the new
4269 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4271 * Separate debug info.
4273 GDB, in conjunction with BINUTILS, now supports a mechanism for
4274 automatically loading debug information from a separate file. Instead
4275 of shipping full debug and non-debug versions of system libraries,
4276 system integrators can now instead ship just the stripped libraries
4277 and optional debug files.
4279 * DWARF 2 Location Expressions
4281 DWARF 2 Location Expressions allow the compiler to more completely
4282 describe the location of variables (even in optimized code) to the
4285 GDB now includes preliminary support for location expressions (support
4286 for DW_OP_piece is still missing).
4290 A number of long standing bugs that caused GDB to die while starting a
4291 Java application have been fixed. GDB's Java support is now
4292 considered "useable".
4294 * GNU/Linux support for fork, vfork, and exec.
4296 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4297 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4300 * GDB supports logging output to a file
4302 There are two new commands, "set logging" and "show logging", which can be
4303 used to capture GDB's output to a file.
4305 * The meaning of "detach" has changed for gdbserver
4307 The "detach" command will now resume the application, as documented. To
4308 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4311 * d10v, m68hc11 `regs' command deprecated
4313 The `info registers' command has been updated so that it displays the
4314 registers using a format identical to the old `regs' command.
4318 A new command, "maint set profile on/off", has been added. This command can
4319 be used to enable or disable profiling while running GDB, to profile a
4320 session or a set of commands. In addition there is a new configure switch,
4321 "--enable-profiling", which will cause GDB to be compiled with profiling
4322 data, for more informative profiling results.
4324 * Default MI syntax changed to "mi2".
4326 The default MI (machine interface) syntax, enabled by the command line
4327 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4328 "mi1", can be enabled by specifying the option "-i=mi1".
4330 Support for the original "mi0" syntax (included in GDB 5.0) has been
4333 Fix for gdb/192: removed extraneous space when displaying frame level.
4334 Fix for gdb/672: update changelist is now output in mi list format.
4335 Fix for gdb/702: a -var-assign that updates the value now shows up
4336 in a subsequent -var-update.
4338 * New native configurations.
4340 FreeBSD/amd64 x86_64-*-freebsd*
4342 * Multi-arched targets.
4344 HP/PA HPUX11 hppa*-*-hpux*
4345 Renesas M32R/D w/simulator m32r-*-elf*
4347 * OBSOLETE configurations and files
4349 Configurations that have been declared obsolete in this release have
4350 been commented out. Unless there is activity to revive these
4351 configurations, the next release of GDB will have their sources
4352 permanently REMOVED.
4354 Z8000 simulator z8k-zilog-none or z8ksim
4355 Matsushita MN10200 w/simulator mn10200-*-*
4356 H8/500 simulator h8500-hitachi-hms or h8500hms
4357 HP/PA running BSD hppa*-*-bsd*
4358 HP/PA running OSF/1 hppa*-*-osf*
4359 HP/PA Pro target hppa*-*-pro*
4360 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4361 Sequent family i[3456]86-sequent-sysv4*
4362 i[3456]86-sequent-sysv*
4363 i[3456]86-sequent-bsd*
4364 Tsqware Sparclet sparclet-*-*
4365 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4367 * REMOVED configurations and files
4370 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4371 IBM AIX PS/2 i[3456]86-*-aix
4372 i386 running Mach 3.0 i[3456]86-*-mach3*
4373 i386 running Mach i[3456]86-*-mach*
4374 i386 running OSF/1 i[3456]86-*osf1mk*
4375 HP/Apollo 68k Family m68*-apollo*-sysv*,
4377 m68*-hp-bsd*, m68*-hp-hpux*
4378 Argonaut Risc Chip (ARC) arc-*-*
4379 Mitsubishi D30V d30v-*-*
4380 Fujitsu FR30 fr30-*-elf*
4381 OS/9000 i[34]86-*-os9k
4382 I960 with MON960 i960-*-coff
4384 * MIPS $fp behavior changed
4386 The convenience variable $fp, for the MIPS, now consistently returns
4387 the address of the current frame's base. Previously, depending on the
4388 context, $fp could refer to either $sp or the current frame's base
4389 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4390 The GNU Source-Level Debugger''.
4392 *** Changes in GDB 5.3:
4394 * GNU/Linux shared library multi-threaded performance improved.
4396 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4397 `/proc', in preference to `ptrace' for memory reads. This may result
4398 in an improvement in the start-up time of multi-threaded, shared
4399 library applications when run under GDB. One GDB user writes: ``loads
4400 shared libs like mad''.
4402 * ``gdbserver'' now supports multi-threaded applications on some targets
4404 Support for debugging multi-threaded applications which use
4405 the GNU/Linux LinuxThreads package has been added for
4406 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4407 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4409 * GDB now supports C/C++ preprocessor macros.
4411 GDB now expands preprocessor macro invocations in C/C++ expressions,
4412 and provides various commands for showing macro definitions and how
4415 The new command `macro expand EXPRESSION' expands any macro
4416 invocations in expression, and shows the result.
4418 The new command `show macro MACRO-NAME' shows the definition of the
4419 macro named MACRO-NAME, and where it was defined.
4421 Most compilers don't include information about macros in the debugging
4422 information by default. In GCC 3.1, for example, you need to compile
4423 your program with the options `-gdwarf-2 -g3'. If the macro
4424 information is present in the executable, GDB will read it.
4426 * Multi-arched targets.
4428 DEC Alpha (partial) alpha*-*-*
4429 DEC VAX (partial) vax-*-*
4431 National Semiconductor NS32000 (partial) ns32k-*-*
4432 Motorola 68000 (partial) m68k-*-*
4433 Motorola MCORE mcore-*-*
4437 Fujitsu FRV architecture added by Red Hat frv*-*-*
4440 * New native configurations
4442 Alpha NetBSD alpha*-*-netbsd*
4443 SH NetBSD sh*-*-netbsdelf*
4444 MIPS NetBSD mips*-*-netbsd*
4445 UltraSPARC NetBSD sparc64-*-netbsd*
4447 * OBSOLETE configurations and files
4449 Configurations that have been declared obsolete in this release have
4450 been commented out. Unless there is activity to revive these
4451 configurations, the next release of GDB will have their sources
4452 permanently REMOVED.
4454 Mitsubishi D30V d30v-*-*
4455 OS/9000 i[34]86-*-os9k
4456 IBM AIX PS/2 i[3456]86-*-aix
4457 Fujitsu FR30 fr30-*-elf*
4458 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4459 Argonaut Risc Chip (ARC) arc-*-*
4460 i386 running Mach 3.0 i[3456]86-*-mach3*
4461 i386 running Mach i[3456]86-*-mach*
4462 i386 running OSF/1 i[3456]86-*osf1mk*
4463 HP/Apollo 68k Family m68*-apollo*-sysv*,
4465 m68*-hp-bsd*, m68*-hp-hpux*
4466 I960 with MON960 i960-*-coff
4468 * OBSOLETE languages
4470 CHILL, a Pascal like language used by telecommunications companies.
4472 * REMOVED configurations and files
4474 AMD 29k family via UDI a29k-amd-udi, udi29k
4475 A29K VxWorks a29k-*-vxworks
4476 AMD 29000 embedded, using EBMON a29k-none-none
4477 AMD 29000 embedded with COFF a29k-none-coff
4478 AMD 29000 embedded with a.out a29k-none-aout
4480 testsuite/gdb.hp/gdb.threads-hp/ directory
4482 * New command "set max-user-call-depth <nnn>"
4484 This command allows the user to limit the call depth of user-defined
4485 commands. The default is 1024.
4487 * Changes in FreeBSD/i386 native debugging.
4489 Support for the "generate-core-file" has been added.
4491 * New commands "dump", "append", and "restore".
4493 These commands allow data to be copied from target memory
4494 to a bfd-format or binary file (dump and append), and back
4495 from a file into memory (restore).
4497 * Improved "next/step" support on multi-processor Alpha Tru64.
4499 The previous single-step mechanism could cause unpredictable problems,
4500 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4501 of a software single-step mechanism prevents this.
4503 *** Changes in GDB 5.2.1:
4511 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4512 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4513 Fix, by Joel Brobecker imported from mainline.
4515 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4516 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4517 Fix, by Fred Fish, imported from mainline.
4519 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4520 Surprisingly enough, it works now.
4521 By Michal Ludvig, imported from mainline.
4523 i386 hardware watchpoint support:
4524 avoid misses on second run for some targets.
4525 By Pierre Muller, imported from mainline.
4527 *** Changes in GDB 5.2:
4529 * New command "set trust-readonly-sections on[off]".
4531 This command is a hint that tells gdb that read-only sections
4532 really are read-only (ie. that their contents will not change).
4533 In this mode, gdb will go to the object file rather than the
4534 target to read memory from read-only sections (such as ".text").
4535 This can be a significant performance improvement on some
4536 (notably embedded) targets.
4538 * New command "generate-core-file" (or "gcore").
4540 This new gdb command allows the user to drop a core file of the child
4541 process state at any time. So far it's been implemented only for
4542 GNU/Linux and Solaris, but should be relatively easily ported to other
4543 hosts. Argument is core file name (defaults to core.<pid>).
4545 * New command line option
4547 GDB now accepts --pid or -p followed by a process id.
4549 * Change in command line behavior -- corefiles vs. process ids.
4551 There is a subtle behavior in the way in which GDB handles
4552 command line arguments. The first non-flag argument is always
4553 a program to debug, but the second non-flag argument may either
4554 be a corefile or a process id. Previously, GDB would attempt to
4555 open the second argument as a corefile, and if that failed, would
4556 issue a superfluous error message and then attempt to attach it as
4557 a process. Now, if the second argument begins with a non-digit,
4558 it will be treated as a corefile. If it begins with a digit,
4559 GDB will attempt to attach it as a process, and if no such process
4560 is found, will then attempt to open it as a corefile.
4562 * Changes in ARM configurations.
4564 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4565 configuration is fully multi-arch.
4567 * New native configurations
4569 ARM NetBSD arm*-*-netbsd*
4570 x86 OpenBSD i[3456]86-*-openbsd*
4571 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4572 Sparc64 running FreeBSD sparc64-*-freebsd*
4576 Sanyo XStormy16 xstormy16-elf
4578 * OBSOLETE configurations and files
4580 Configurations that have been declared obsolete in this release have
4581 been commented out. Unless there is activity to revive these
4582 configurations, the next release of GDB will have their sources
4583 permanently REMOVED.
4585 AMD 29k family via UDI a29k-amd-udi, udi29k
4586 A29K VxWorks a29k-*-vxworks
4587 AMD 29000 embedded, using EBMON a29k-none-none
4588 AMD 29000 embedded with COFF a29k-none-coff
4589 AMD 29000 embedded with a.out a29k-none-aout
4591 testsuite/gdb.hp/gdb.threads-hp/ directory
4593 * REMOVED configurations and files
4595 TI TMS320C80 tic80-*-*
4597 PowerPC Solaris powerpcle-*-solaris*
4598 PowerPC Windows NT powerpcle-*-cygwin32
4599 PowerPC Netware powerpc-*-netware*
4600 Harris/CXUX m88k m88*-harris-cxux*
4601 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4602 ns32k-utek-sysv* ns32k-utek-*
4603 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4604 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4605 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4606 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4607 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4609 * Changes to command line processing
4611 The new `--args' feature can be used to specify command-line arguments
4612 for the inferior from gdb's command line.
4614 * Changes to key bindings
4616 There is a new `operate-and-get-next' function bound to `C-o'.
4618 *** Changes in GDB 5.1.1
4620 Fix compile problem on DJGPP.
4622 Fix a problem with floating-point registers on the i386 being
4625 Fix to stop GDB crashing on .debug_str debug info.
4627 Numerous documentation fixes.
4629 Numerous testsuite fixes.
4631 *** Changes in GDB 5.1:
4633 * New native configurations
4635 Alpha FreeBSD alpha*-*-freebsd*
4636 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4637 MIPS GNU/Linux mips*-*-linux*
4638 MIPS SGI Irix 6.x mips*-sgi-irix6*
4639 ia64 AIX ia64-*-aix*
4640 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4644 Motorola 68HC11 and 68HC12 m68hc11-elf
4646 UltraSparc running GNU/Linux sparc64-*-linux*
4648 * OBSOLETE configurations and files
4650 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4651 Harris/CXUX m88k m88*-harris-cxux*
4652 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4653 ns32k-utek-sysv* ns32k-utek-*
4654 TI TMS320C80 tic80-*-*
4656 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4657 PowerPC Solaris powerpcle-*-solaris*
4658 PowerPC Windows NT powerpcle-*-cygwin32
4659 PowerPC Netware powerpc-*-netware*
4660 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4661 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4662 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4663 Apple Macintosh (MPW) host N/A
4665 stuff.c (Program to stuff files into a specially prepared space in kdb)
4666 kdb-start.c (Main loop for the standalone kernel debugger)
4668 Configurations that have been declared obsolete in this release have
4669 been commented out. Unless there is activity to revive these
4670 configurations, the next release of GDB will have their sources
4671 permanently REMOVED.
4673 * REMOVED configurations and files
4675 Altos 3068 m68*-altos-*
4676 Convex c1-*-*, c2-*-*
4678 ARM RISCix arm-*-* (as host)
4682 * GDB has been converted to ISO C.
4684 GDB's source code has been converted to ISO C. In particular, the
4685 sources are fully protoized, and rely on standard headers being
4690 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4692 * The MI enabled by default.
4694 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4695 revised and enabled by default. Packages which use GDB as a debugging
4696 engine behind a UI or another front end are encouraged to switch to
4697 using the GDB/MI interface, instead of the old annotations interface
4698 which is now deprecated.
4700 * Support for debugging Pascal programs.
4702 GDB now includes support for debugging Pascal programs. The following
4703 main features are supported:
4705 - Pascal-specific data types such as sets;
4707 - automatic recognition of Pascal sources based on file-name
4710 - Pascal-style display of data types, variables, and functions;
4712 - a Pascal expression parser.
4714 However, some important features are not yet supported.
4716 - Pascal string operations are not supported at all;
4718 - there are some problems with boolean types;
4720 - Pascal type hexadecimal constants are not supported
4721 because they conflict with the internal variables format;
4723 - support for Pascal objects and classes is not full yet;
4725 - unlike Pascal, GDB is case-sensitive for symbol names.
4727 * Changes in completion.
4729 Commands such as `shell', `run' and `set args', which pass arguments
4730 to inferior programs, now complete on file names, similar to what
4731 users expect at the shell prompt.
4733 Commands which accept locations, such as `disassemble', `print',
4734 `breakpoint', `until', etc. now complete on filenames as well as
4735 program symbols. Thus, if you type "break foob TAB", and the source
4736 files linked into the programs include `foobar.c', that file name will
4737 be one of the candidates for completion. However, file names are not
4738 considered for completion after you typed a colon that delimits a file
4739 name from a name of a function in that file, as in "break foo.c:bar".
4741 `set demangle-style' completes on available demangling styles.
4743 * New platform-independent commands:
4745 It is now possible to define a post-hook for a command as well as a
4746 hook that runs before the command. For more details, see the
4747 documentation of `hookpost' in the GDB manual.
4749 * Changes in GNU/Linux native debugging.
4751 Support for debugging multi-threaded programs has been completely
4752 revised for all platforms except m68k and sparc. You can now debug as
4753 many threads as your system allows you to have.
4755 Attach/detach is supported for multi-threaded programs.
4757 Support for SSE registers was added for x86. This doesn't work for
4758 multi-threaded programs though.
4760 * Changes in MIPS configurations.
4762 Multi-arch support is enabled for all MIPS configurations.
4764 GDB can now be built as native debugger on SGI Irix 6.x systems for
4765 debugging n32 executables. (Debugging 64-bit executables is not yet
4768 * Unified support for hardware watchpoints in all x86 configurations.
4770 Most (if not all) native x86 configurations support hardware-assisted
4771 breakpoints and watchpoints in a unified manner. This support
4772 implements debug register sharing between watchpoints, which allows to
4773 put a virtually infinite number of watchpoints on the same address,
4774 and also supports watching regions up to 16 bytes with several debug
4777 The new maintenance command `maintenance show-debug-regs' toggles
4778 debugging print-outs in functions that insert, remove, and test
4779 watchpoints and hardware breakpoints.
4781 * Changes in the DJGPP native configuration.
4783 New command ``info dos sysinfo'' displays assorted information about
4784 the CPU, OS, memory, and DPMI server.
4786 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4787 display information about segment descriptors stored in GDT, LDT, and
4790 New commands ``info dos pde'' and ``info dos pte'' display entries
4791 from Page Directory and Page Tables (for now works with CWSDPMI only).
4792 New command ``info dos address-pte'' displays the Page Table entry for
4793 a given linear address.
4795 GDB can now pass command lines longer than 126 characters to the
4796 program being debugged (requires an update to the libdbg.a library
4797 which is part of the DJGPP development kit).
4799 DWARF2 debug info is now supported.
4801 It is now possible to `step' and `next' through calls to `longjmp'.
4803 * Changes in documentation.
4805 All GDB documentation was converted to GFDL, the GNU Free
4806 Documentation License.
4808 Tracepoints-related commands are now fully documented in the GDB
4811 TUI, the Text-mode User Interface, is now documented in the manual.
4813 Tracepoints-related commands are now fully documented in the GDB
4816 The "GDB Internals" manual now has an index. It also includes
4817 documentation of `ui_out' functions, GDB coding standards, x86
4818 hardware watchpoints, and memory region attributes.
4820 * GDB's version number moved to ``version.in''
4822 The Makefile variable VERSION has been replaced by the file
4823 ``version.in''. People creating GDB distributions should update the
4824 contents of this file.
4828 GUD support is now a standard part of the EMACS distribution.
4830 *** Changes in GDB 5.0:
4832 * Improved support for debugging FP programs on x86 targets
4834 Unified and much-improved support for debugging floating-point
4835 programs on all x86 targets. In particular, ``info float'' now
4836 displays the FP registers in the same format on all x86 targets, with
4837 greater level of detail.
4839 * Improvements and bugfixes in hardware-assisted watchpoints
4841 It is now possible to watch array elements, struct members, and
4842 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4843 on x86 targets no longer erroneously trigger when the address is
4846 * Improvements in the native DJGPP version of GDB
4848 The distribution now includes all the scripts and auxiliary files
4849 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4850 machines ``out of the box''.
4852 The DJGPP version can now debug programs that use signals. It is
4853 possible to catch signals that happened in the debuggee, deliver
4854 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4855 would kill the program being debugged.) Programs that hook hardware
4856 interrupts (keyboard, timer, etc.) can also be debugged.
4858 It is now possible to debug DJGPP programs that redirect their
4859 standard handles or switch them to raw (as opposed to cooked) mode, or
4860 even close them. The command ``run < foo > bar'' works as expected,
4861 and ``info terminal'' reports useful information about the debuggee's
4862 terminal, including raw/cooked mode, redirection, etc.
4864 The DJGPP version now uses termios functions for console I/O, which
4865 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4868 DOS-style file names with drive letters are now fully supported by
4871 It is now possible to debug DJGPP programs that switch their working
4872 directory. It is also possible to rerun the debuggee any number of
4873 times without restarting GDB; thus, you can use the same setup,
4874 breakpoints, etc. for many debugging sessions.
4876 * New native configurations
4878 ARM GNU/Linux arm*-*-linux*
4879 PowerPC GNU/Linux powerpc-*-linux*
4883 Motorola MCore mcore-*-*
4884 x86 VxWorks i[3456]86-*-vxworks*
4885 PowerPC VxWorks powerpc-*-vxworks*
4886 TI TMS320C80 tic80-*-*
4888 * OBSOLETE configurations
4890 Altos 3068 m68*-altos-*
4891 Convex c1-*-*, c2-*-*
4893 ARM RISCix arm-*-* (as host)
4896 Configurations that have been declared obsolete will be commented out,
4897 but the code will be left in place. If there is no activity to revive
4898 these configurations before the next release of GDB, the sources will
4899 be permanently REMOVED.
4901 * Gould support removed
4903 Support for the Gould PowerNode and NP1 has been removed.
4905 * New features for SVR4
4907 On SVR4 native platforms (such as Solaris), if you attach to a process
4908 without first loading a symbol file, GDB will now attempt to locate and
4909 load symbols from the running process's executable file.
4911 * Many C++ enhancements
4913 C++ support has been greatly improved. Overload resolution now works properly
4914 in almost all cases. RTTI support is on the way.
4916 * Remote targets can connect to a sub-program
4918 A popen(3) style serial-device has been added. This device starts a
4919 sub-process (such as a stand-alone simulator) and then communicates
4920 with that. The sub-program to run is specified using the syntax
4921 ``|<program> <args>'' vis:
4923 (gdb) set remotedebug 1
4924 (gdb) target extended-remote |mn10300-elf-sim program-args
4926 * MIPS 64 remote protocol
4928 A long standing bug in the mips64 remote protocol where by GDB
4929 expected certain 32 bit registers (ex SR) to be transfered as 32
4930 instead of 64 bits has been fixed.
4932 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4933 added to provide backward compatibility with older versions of GDB.
4935 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4937 The command ``set remotebinarydownload'' command has been replaced by
4938 ``set remote X-packet''. Other commands in ``set remote'' family
4939 include ``set remote P-packet''.
4941 * Breakpoint commands accept ranges.
4943 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4944 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4945 ``tracepoint passcount'' also accepts a range of tracepoints.
4947 * ``apropos'' command added.
4949 The ``apropos'' command searches through command names and
4950 documentation strings, printing out matches, making it much easier to
4951 try to find a command that does what you are looking for.
4955 A new machine oriented interface (MI) has been added to GDB. This
4956 interface is designed for debug environments running GDB as a separate
4957 process. This is part of the long term libGDB project. See the
4958 "GDB/MI" chapter of the GDB manual for further information. It can be
4959 enabled by configuring with:
4961 .../configure --enable-gdbmi
4963 *** Changes in GDB-4.18:
4965 * New native configurations
4967 HP-UX 10.20 hppa*-*-hpux10.20
4968 HP-UX 11.x hppa*-*-hpux11.0*
4969 M68K GNU/Linux m68*-*-linux*
4973 Fujitsu FR30 fr30-*-elf*
4974 Intel StrongARM strongarm-*-*
4975 Mitsubishi D30V d30v-*-*
4977 * OBSOLETE configurations
4979 Gould PowerNode, NP1 np1-*-*, pn-*-*
4981 Configurations that have been declared obsolete will be commented out,
4982 but the code will be left in place. If there is no activity to revive
4983 these configurations before the next release of GDB, the sources will
4984 be permanently REMOVED.
4988 As a compatibility experiment, GDB's source files buildsym.h and
4989 buildsym.c have been converted to pure standard C, no longer
4990 containing any K&R compatibility code. We believe that all systems in
4991 use today either come with a standard C compiler, or have a GCC port
4992 available. If this is not true, please report the affected
4993 configuration to bug-gdb@gnu.org immediately. See the README file for
4994 information about getting a standard C compiler if you don't have one
4999 GDB now uses readline 2.2.
5001 * set extension-language
5003 You can now control the mapping between filename extensions and source
5004 languages by using the `set extension-language' command. For instance,
5005 you can ask GDB to treat .c files as C++ by saying
5006 set extension-language .c c++
5007 The command `info extensions' lists all of the recognized extensions
5008 and their associated languages.
5010 * Setting processor type for PowerPC and RS/6000
5012 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5013 you can use the `set processor' command to specify what variant of the
5014 PowerPC family you are debugging. The command
5018 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5019 following PowerPC and RS6000 variants:
5021 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5022 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5024 403GC IBM PowerPC 403GC
5025 505 Motorola PowerPC 505
5026 860 Motorola PowerPC 860 or 850
5027 601 Motorola PowerPC 601
5028 602 Motorola PowerPC 602
5029 603 Motorola/IBM PowerPC 603 or 603e
5030 604 Motorola PowerPC 604 or 604e
5031 750 Motorola/IBM PowerPC 750 or 750
5033 At the moment, this command just tells GDB what to name the
5034 special-purpose processor registers. Since almost all the affected
5035 registers are inaccessible to user-level programs, this command is
5036 only useful for remote debugging in its present form.
5040 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5041 more extensive support for HP-UX. Added features include shared
5042 library support, kernel threads and hardware watchpoints for 11.00,
5043 support for HP's ANSI C and C++ compilers, and a compatibility mode
5044 for xdb and dbx commands.
5048 HP's donation includes the new concept of catchpoints, which is a
5049 generalization of the old catch command. On HP-UX, it is now possible
5050 to catch exec, fork, and vfork, as well as library loading.
5052 This means that the existing catch command has changed; its first
5053 argument now specifies the type of catch to be set up. See the
5054 output of "help catch" for a list of catchpoint types.
5056 * Debugging across forks
5058 On HP-UX, you can choose which process to debug when a fork() happens
5063 HP has donated a curses-based terminal user interface (TUI). To get
5064 it, build with --enable-tui. Although this can be enabled for any
5065 configuration, at present it only works for native HP debugging.
5067 * GDB remote protocol additions
5069 A new protocol packet 'X' that writes binary data is now available.
5070 Default behavior is to try 'X', then drop back to 'M' if the stub
5071 fails to respond. The settable variable `remotebinarydownload'
5072 allows explicit control over the use of 'X'.
5074 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5075 full 64-bit address. The command
5077 set remoteaddresssize 32
5079 can be used to revert to the old behaviour. For existing remote stubs
5080 the change should not be noticed, as the additional address information
5083 In order to assist in debugging stubs, you may use the maintenance
5084 command `packet' to send any text string to the stub. For instance,
5086 maint packet heythere
5088 sends the packet "$heythere#<checksum>". Note that it is very easy to
5089 disrupt a debugging session by sending the wrong packet at the wrong
5092 The compare-sections command allows you to compare section data on the
5093 target to what is in the executable file without uploading or
5094 downloading, by comparing CRC checksums.
5096 * Tracing can collect general expressions
5098 You may now collect general expressions at tracepoints. This requires
5099 further additions to the target-side stub; see tracepoint.c and
5100 doc/agentexpr.texi for further details.
5102 * mask-address variable for Mips
5104 For Mips targets, you may control the zeroing of the upper 32 bits of
5105 a 64-bit address by entering `set mask-address on'. This is mainly
5106 of interest to users of embedded R4xxx and R5xxx processors.
5108 * Higher serial baud rates
5110 GDB's serial code now allows you to specify baud rates 57600, 115200,
5111 230400, and 460800 baud. (Note that your host system may not be able
5112 to achieve all of these rates.)
5116 The i960 configuration now includes an initial implementation of a
5117 builtin simulator, contributed by Jim Wilson.
5120 *** Changes in GDB-4.17:
5122 * New native configurations
5124 Alpha GNU/Linux alpha*-*-linux*
5125 Unixware 2.x i[3456]86-unixware2*
5126 Irix 6.x mips*-sgi-irix6*
5127 PowerPC GNU/Linux powerpc-*-linux*
5128 PowerPC Solaris powerpcle-*-solaris*
5129 Sparc GNU/Linux sparc-*-linux*
5130 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5134 Argonaut Risc Chip (ARC) arc-*-*
5135 Hitachi H8/300S h8300*-*-*
5136 Matsushita MN10200 w/simulator mn10200-*-*
5137 Matsushita MN10300 w/simulator mn10300-*-*
5138 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5139 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5140 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5141 Mitsubishi D10V w/simulator d10v-*-*
5142 Mitsubishi M32R/D w/simulator m32r-*-elf*
5143 Tsqware Sparclet sparclet-*-*
5144 NEC V850 w/simulator v850-*-*
5146 * New debugging protocols
5148 ARM with RDI protocol arm*-*-*
5149 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5150 DDB and LSI variants of PMON protocol mips*-*-*
5151 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5152 PowerPC with SDS protocol powerpc{,le}-*-eabi
5153 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5157 All configurations can now understand and use the DWARF 2 debugging
5158 format. The choice is automatic, if the symbol file contains DWARF 2
5163 GDB now includes basic Java language support. This support is
5164 only useful with Java compilers that produce native machine code.
5166 * solib-absolute-prefix and solib-search-path
5168 For SunOS and SVR4 shared libraries, you may now set the prefix for
5169 loading absolute shared library symbol files, and the search path for
5170 locating non-absolute shared library symbol files.
5172 * Live range splitting
5174 GDB can now effectively debug code for which GCC has performed live
5175 range splitting as part of its optimization. See gdb/doc/LRS for
5176 more details on the expected format of the stabs information.
5180 GDB's support for the GNU Hurd, including thread debugging, has been
5181 updated to work with current versions of the Hurd.
5185 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5186 instruction set. ARM GDB automatically detects when Thumb
5187 instructions are in use, and adjusts disassembly and backtracing
5192 GDB's MIPS target configurations now handle the MIP16 16-bit
5197 GDB now includes support for overlays; if an executable has been
5198 linked such that multiple sections are based at the same address, GDB
5199 will decide which section to use for symbolic info. You can choose to
5200 control the decision manually, using overlay commands, or implement
5201 additional target-side support and use "overlay load-target" to bring
5202 in the overlay mapping. Do "help overlay" for more detail.
5206 The command "info symbol <address>" displays information about
5207 the symbol at the specified address.
5211 The standard remote protocol now includes an extension that allows
5212 asynchronous collection and display of trace data. This requires
5213 extensive support in the target-side debugging stub. Tracing mode
5214 includes a new interaction mode in GDB and new commands: see the
5215 file tracepoint.c for more details.
5219 Configurations for embedded MIPS now include a simulator contributed
5220 by Cygnus Solutions. The simulator supports the instruction sets
5221 of most MIPS variants.
5225 Sparc configurations may now include the ERC32 simulator contributed
5226 by the European Space Agency. The simulator is not built into
5227 Sparc targets by default; configure with --enable-sim to include it.
5231 For target configurations that may include multiple variants of a
5232 basic architecture (such as MIPS and SH), you may now set the
5233 architecture explicitly. "set arch" sets, "info arch" lists
5234 the possible architectures.
5236 *** Changes in GDB-4.16:
5238 * New native configurations
5240 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5241 M68K NetBSD m68k-*-netbsd*
5242 PowerPC AIX 4.x powerpc-*-aix*
5243 PowerPC MacOS powerpc-*-macos*
5244 PowerPC Windows NT powerpcle-*-cygwin32
5245 RS/6000 AIX 4.x rs6000-*-aix4*
5249 ARM with RDP protocol arm-*-*
5250 I960 with MON960 i960-*-coff
5251 MIPS VxWorks mips*-*-vxworks*
5252 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5253 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5255 Matra Sparclet sparclet-*-*
5259 The powerpc-eabi configuration now includes the PSIM simulator,
5260 contributed by Andrew Cagney, with assistance from Mike Meissner.
5261 PSIM is a very elaborate model of the PowerPC, including not only
5262 basic instruction set execution, but also details of execution unit
5263 performance and I/O hardware. See sim/ppc/README for more details.
5267 GDB now works with Solaris 2.5.
5269 * Windows 95/NT native
5271 GDB will now work as a native debugger on Windows 95 and Windows NT.
5272 To build it from source, you must use the "gnu-win32" environment,
5273 which uses a DLL to emulate enough of Unix to run the GNU tools.
5274 Further information, binaries, and sources are available at
5275 ftp.cygnus.com, under pub/gnu-win32.
5277 * dont-repeat command
5279 If a user-defined command includes the command `dont-repeat', then the
5280 command will not be repeated if the user just types return. This is
5281 useful if the command is time-consuming to run, so that accidental
5282 extra keystrokes don't run the same command many times.
5284 * Send break instead of ^C
5286 The standard remote protocol now includes an option to send a break
5287 rather than a ^C to the target in order to interrupt it. By default,
5288 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5290 * Remote protocol timeout
5292 The standard remote protocol includes a new variable `remotetimeout'
5293 that allows you to set the number of seconds before GDB gives up trying
5294 to read from the target. The default value is 2.
5296 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5298 By default GDB will automatically keep track of objects as they are
5299 loaded and unloaded by the dynamic linker. By using the command `set
5300 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5301 when shared library events occur, thus allowing you to set breakpoints
5302 in shared libraries which are explicitly loaded by the inferior.
5304 Note this feature does not work on hpux8. On hpux9 you must link
5305 /usr/lib/end.o into your program. This feature should work
5306 automatically on hpux10.
5308 * Irix 5.x hardware watchpoint support
5310 Irix 5 configurations now support the use of hardware watchpoints.
5312 * Mips protocol "SYN garbage limit"
5314 When debugging a Mips target using the `target mips' protocol, you
5315 may set the number of characters that GDB will ignore by setting
5316 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5317 every character. The default value is 1050.
5319 * Recording and replaying remote debug sessions
5321 If you set `remotelogfile' to the name of a file, gdb will write to it
5322 a recording of a remote debug session. This recording may then be
5323 replayed back to gdb using "gdbreplay". See gdbserver/README for
5324 details. This is useful when you have a problem with GDB while doing
5325 remote debugging; you can make a recording of the session and send it
5326 to someone else, who can then recreate the problem.
5328 * Speedups for remote debugging
5330 GDB includes speedups for downloading and stepping MIPS systems using
5331 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5332 and more efficient S-record downloading.
5334 * Memory use reductions and statistics collection
5336 GDB now uses less memory and reports statistics about memory usage.
5337 Try the `maint print statistics' command, for example.
5339 *** Changes in GDB-4.15:
5341 * Psymtabs for XCOFF
5343 The symbol reader for AIX GDB now uses partial symbol tables. This
5344 can greatly improve startup time, especially for large executables.
5346 * Remote targets use caching
5348 Remote targets now use a data cache to speed up communication with the
5349 remote side. The data cache could lead to incorrect results because
5350 it doesn't know about volatile variables, thus making it impossible to
5351 debug targets which use memory mapped I/O devices. `set remotecache
5352 off' turns the the data cache off.
5354 * Remote targets may have threads
5356 The standard remote protocol now includes support for multiple threads
5357 in the target system, using new protocol commands 'H' and 'T'. See
5358 gdb/remote.c for details.
5362 If GDB is configured with `--enable-netrom', then it will include
5363 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5364 acts as though it is a bank of ROM on the target board, but you can
5365 write into it over the network. GDB's support consists only of
5366 support for fast loading into the emulated ROM; to debug, you must use
5367 another protocol, such as standard remote protocol. The usual
5368 sequence is something like
5370 target nrom <netrom-hostname>
5372 target remote <netrom-hostname>:1235
5376 GDB now includes support for the Apple Macintosh, as a host only. It
5377 may be run as either an MPW tool or as a standalone application, and
5378 it can debug through the serial port. All the usual GDB commands are
5379 available, but to the target command, you must supply "serial" as the
5380 device type instead of "/dev/ttyXX". See mpw-README in the main
5381 directory for more information on how to build. The MPW configuration
5382 scripts */mpw-config.in support only a few targets, and only the
5383 mips-idt-ecoff target has been tested.
5387 GDB configuration now uses autoconf. This is not user-visible,
5388 but does simplify configuration and building.
5392 GDB now supports hpux10.
5394 *** Changes in GDB-4.14:
5396 * New native configurations
5398 x86 FreeBSD i[345]86-*-freebsd
5399 x86 NetBSD i[345]86-*-netbsd
5400 NS32k NetBSD ns32k-*-netbsd
5401 Sparc NetBSD sparc-*-netbsd
5405 A29K VxWorks a29k-*-vxworks
5406 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5407 CPU32 EST-300 emulator m68*-*-est*
5408 PowerPC ELF powerpc-*-elf
5411 * Alpha OSF/1 support for procfs
5413 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5414 possible to attach to running processes. As the mounting of the /proc
5415 filesystem is optional on the Alpha, GDB automatically determines
5416 the availability of /proc during startup. This can lead to problems
5417 if /proc is unmounted after GDB has been started.
5419 * Arguments to user-defined commands
5421 User commands may accept up to 10 arguments separated by whitespace.
5422 Arguments are accessed within the user command via $arg0..$arg9. A
5425 print $arg0 + $arg1 + $arg2
5427 To execute the command use:
5430 Defines the command "adder" which prints the sum of its three arguments.
5431 Note the arguments are text substitutions, so they may reference variables,
5432 use complex expressions, or even perform inferior function calls.
5434 * New `if' and `while' commands
5436 This makes it possible to write more sophisticated user-defined
5437 commands. Both commands take a single argument, which is the
5438 expression to evaluate, and must be followed by the commands to
5439 execute, one per line, if the expression is nonzero, the list being
5440 terminated by the word `end'. The `if' command list may include an
5441 `else' word, which causes the following commands to be executed only
5442 if the expression is zero.
5444 * Fortran source language mode
5446 GDB now includes partial support for Fortran 77. It will recognize
5447 Fortran programs and can evaluate a subset of Fortran expressions, but
5448 variables and functions may not be handled correctly. GDB will work
5449 with G77, but does not yet know much about symbols emitted by other
5452 * Better HPUX support
5454 Most debugging facilities now work on dynamic executables for HPPAs
5455 running hpux9 or later. You can attach to running dynamically linked
5456 processes, but by default the dynamic libraries will be read-only, so
5457 for instance you won't be able to put breakpoints in them. To change
5458 that behavior do the following before running the program:
5464 This will cause the libraries to be mapped private and read-write.
5465 To revert to the normal behavior, do this:
5471 You cannot set breakpoints or examine data in the library until after
5472 the library is loaded if the function/data symbols do not have
5475 GDB can now also read debug symbols produced by the HP C compiler on
5476 HPPAs (sorry, no C++, Fortran or 68k support).
5478 * Target byte order now dynamically selectable
5480 You can choose which byte order to use with a target system, via the
5481 commands "set endian big" and "set endian little", and you can see the
5482 current setting by using "show endian". You can also give the command
5483 "set endian auto", in which case GDB will use the byte order
5484 associated with the executable. Currently, only embedded MIPS
5485 configurations support dynamic selection of target byte order.
5487 * New DOS host serial code
5489 This version uses DPMI interrupts to handle buffered I/O, so you
5490 no longer need to run asynctsr when debugging boards connected to
5493 *** Changes in GDB-4.13:
5495 * New "complete" command
5497 This lists all the possible completions for the rest of the line, if it
5498 were to be given as a command itself. This is intended for use by emacs.
5500 * Trailing space optional in prompt
5502 "set prompt" no longer adds a space for you after the prompt you set. This
5503 allows you to set a prompt which ends in a space or one that does not.
5505 * Breakpoint hit counts
5507 "info break" now displays a count of the number of times the breakpoint
5508 has been hit. This is especially useful in conjunction with "ignore"; you
5509 can ignore a large number of breakpoint hits, look at the breakpoint info
5510 to see how many times the breakpoint was hit, then run again, ignoring one
5511 less than that number, and this will get you quickly to the last hit of
5514 * Ability to stop printing at NULL character
5516 "set print null-stop" will cause GDB to stop printing the characters of
5517 an array when the first NULL is encountered. This is useful when large
5518 arrays actually contain only short strings.
5520 * Shared library breakpoints
5522 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5523 breakpoints in shared libraries before the executable is run.
5525 * Hardware watchpoints
5527 There is a new hardware breakpoint for the watch command for sparclite
5528 targets. See gdb/sparclite/hw_breakpoint.note.
5530 Hardware watchpoints are also now supported under GNU/Linux.
5534 Annotations have been added. These are for use with graphical interfaces,
5535 and are still experimental. Currently only gdba.el uses these.
5537 * Improved Irix 5 support
5539 GDB now works properly with Irix 5.2.
5541 * Improved HPPA support
5543 GDB now works properly with the latest GCC and GAS.
5545 * New native configurations
5547 Sequent PTX4 i[34]86-sequent-ptx4
5548 HPPA running OSF/1 hppa*-*-osf*
5549 Atari TT running SVR4 m68*-*-sysv4*
5550 RS/6000 LynxOS rs6000-*-lynxos*
5554 OS/9000 i[34]86-*-os9k
5555 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5558 * Hitachi SH7000 and E7000-PC ICE support
5560 There is now support for communicating with the Hitachi E7000-PC ICE.
5561 This is available automatically when GDB is configured for the SH.
5565 As usual, a variety of small fixes and improvements, both generic
5566 and configuration-specific. See the ChangeLog for more detail.
5568 *** Changes in GDB-4.12:
5570 * Irix 5 is now supported
5574 GDB-4.12 on the HPPA has a number of changes which make it unable
5575 to debug the output from the currently released versions of GCC and
5576 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5577 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5578 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5581 *** Changes in GDB-4.11:
5583 * User visible changes:
5587 The "set remotedebug" option is now consistent between the mips remote
5588 target, remote targets using the gdb-specific protocol, UDI (AMD's
5589 debug protocol for the 29k) and the 88k bug monitor. It is now an
5590 integer specifying a debug level (normally 0 or 1, but 2 means more
5591 debugging info for the mips target).
5593 * DEC Alpha native support
5595 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5596 debug info, but GDB works fairly well with the DEC compiler and should
5597 work with a future GCC release. See the README file for a few
5598 Alpha-specific notes.
5600 * Preliminary thread implementation
5602 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5604 * LynxOS native and target support for 386
5606 This release has been hosted on LynxOS 2.2, and also can be configured
5607 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5610 * Improvements in C++ mangling/demangling.
5612 This release has much better g++ debugging, specifically in name
5613 mangling/demangling, virtual function calls, print virtual table,
5614 call methods, ...etc.
5616 *** Changes in GDB-4.10:
5618 * User visible changes:
5620 Remote debugging using the GDB-specific (`target remote') protocol now
5621 supports the `load' command. This is only useful if you have some
5622 other way of getting the stub to the target system, and you can put it
5623 somewhere in memory where it won't get clobbered by the download.
5625 Filename completion now works.
5627 When run under emacs mode, the "info line" command now causes the
5628 arrow to point to the line specified. Also, "info line" prints
5629 addresses in symbolic form (as well as hex).
5631 All vxworks based targets now support a user settable option, called
5632 vxworks-timeout. This option represents the number of seconds gdb
5633 should wait for responses to rpc's. You might want to use this if
5634 your vxworks target is, perhaps, a slow software simulator or happens
5635 to be on the far side of a thin network line.
5639 This release contains support for using a DEC alpha as a GDB host for
5640 cross debugging. Native alpha debugging is not supported yet.
5643 *** Changes in GDB-4.9:
5647 This is the first GDB release which is accompanied by a matching testsuite.
5648 The testsuite requires installation of dejagnu, which should be available
5649 via ftp from most sites that carry GNU software.
5653 'Cfront' style demangling has had its name changed to 'ARM' style, to
5654 emphasize that it was written from the specifications in the C++ Annotated
5655 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5656 disclaimers, it still generated too much confusion with users attempting to
5657 use gdb with AT&T cfront.
5661 GDB now uses a standard remote interface to a simulator library.
5662 So far, the library contains simulators for the Zilog Z8001/2, the
5663 Hitachi H8/300, H8/500 and Super-H.
5665 * New targets supported
5667 H8/300 simulator h8300-hitachi-hms or h8300hms
5668 H8/500 simulator h8500-hitachi-hms or h8500hms
5669 SH simulator sh-hitachi-hms or sh
5670 Z8000 simulator z8k-zilog-none or z8ksim
5671 IDT MIPS board over serial line mips-idt-ecoff
5673 Cross-debugging to GO32 targets is supported. It requires a custom
5674 version of the i386-stub.c module which is integrated with the
5675 GO32 memory extender.
5677 * New remote protocols
5679 MIPS remote debugging protocol.
5681 * New source languages supported
5683 This version includes preliminary support for Chill, a Pascal like language
5684 used by telecommunications companies. Chill support is also being integrated
5685 into the GNU compiler, but we don't know when it will be publically available.
5688 *** Changes in GDB-4.8:
5690 * HP Precision Architecture supported
5692 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5693 version of this support was available as a set of patches from the
5694 University of Utah. GDB does not support debugging of programs
5695 compiled with the HP compiler, because HP will not document their file
5696 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5697 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5699 Many problems in the preliminary version have been fixed.
5701 * Faster and better demangling
5703 We have improved template demangling and fixed numerous bugs in the GNU style
5704 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5705 character types (wchar_t) are now supported. Demangling of each symbol is now
5706 only done once, and is cached when the symbol table for a file is read in.
5707 This results in a small increase in memory usage for C programs, a moderate
5708 increase in memory usage for C++ programs, and a fantastic speedup in
5711 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5712 from the specifications in the Annotated Reference Manual, which AT&T's
5713 compiler does not actually implement.
5715 * G++ multiple inheritance compiler problem
5717 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5718 inheritance lattices was reworked to properly discover ambiguities. We
5719 recently found an example which causes this new algorithm to fail in a
5720 very subtle way, producing bad debug information for those classes.
5721 The file 'gcc.patch' (in this directory) can be applied to gcc to
5722 circumvent the problem. A future GCC release will contain a complete
5725 The previous G++ debug info problem (mentioned below for the gdb-4.7
5726 release) is fixed in gcc version 2.3.2.
5728 * Improved configure script
5730 The `configure' script will now attempt to guess your system type if
5731 you don't supply a host system type. The old scheme of supplying a
5732 host system triplet is preferable over using this. All the magic is
5733 done in the new `config.guess' script. Examine it for details.
5735 We have also brought our configure script much more in line with the FSF's
5736 version. It now supports the --with-xxx options. In particular,
5737 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5738 The resulting GDB will not be able to read arbitrary object file formats --
5739 only the format ``expected'' to be used on the configured target system.
5740 We hope to make this the default in a future release.
5742 * Documentation improvements
5744 There's new internal documentation on how to modify GDB, and how to
5745 produce clean changes to the code. We implore people to read it
5746 before submitting changes.
5748 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5749 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5750 `info' files are also provided. To build `info' files from scratch,
5751 you will need the latest `makeinfo' release, which will be available in
5752 a future texinfo-X.Y release.
5754 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5755 We're not sure exactly which versions have this problem, but it has
5756 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5757 or better. If that isn't possible, there is a patch in
5758 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5759 around this problem.
5763 GDB now supports array constants that can be used in expressions typed in by
5764 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5765 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5768 The new directory `gdb/sparclite' contains a program that demonstrates
5769 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5771 * New native hosts supported
5773 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5774 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5776 * New targets supported
5778 AMD 29k family via UDI a29k-amd-udi or udi29k
5780 * New file formats supported
5782 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5783 HPUX core files, and SCO 3.2v2 core files.
5787 Attaching to processes now works again; thanks for the many bug reports.
5789 We have also stomped on a bunch of core dumps caused by
5790 printf_filtered("%s") problems.
5792 We eliminated a copyright problem on the rpc and ptrace header files
5793 for VxWorks, which was discovered at the last minute during the 4.7
5794 release. You should now be able to build a VxWorks GDB.
5796 You can now interrupt gdb while an attached process is running. This
5797 will cause the attached process to stop, and give control back to GDB.
5799 We fixed problems caused by using too many file descriptors
5800 for reading symbols from object files and libraries. This was
5801 especially a problem for programs that used many (~100) shared
5804 The `step' command now only enters a subroutine if there is line number
5805 information for the subroutine. Otherwise it acts like the `next'
5806 command. Previously, `step' would enter subroutines if there was
5807 any debugging information about the routine. This avoids problems
5808 when using `cc -g1' on MIPS machines.
5810 * Internal improvements
5812 GDB's internal interfaces have been improved to make it easier to support
5813 debugging of multiple languages in the future.
5815 GDB now uses a common structure for symbol information internally.
5816 Minimal symbols (derived from linkage symbols in object files), partial
5817 symbols (from a quick scan of debug information), and full symbols
5818 contain a common subset of information, making it easier to write
5819 shared code that handles any of them.
5821 * New command line options
5823 We now accept --silent as an alias for --quiet.
5827 The memory-mapped-malloc library is now licensed under the GNU Library
5828 General Public License.
5830 *** Changes in GDB-4.7:
5832 * Host/native/target split
5834 GDB has had some major internal surgery to untangle the support for
5835 hosts and remote targets. Now, when you configure GDB for a remote
5836 target, it will no longer load in all of the support for debugging
5837 local programs on the host. When fully completed and tested, this will
5838 ensure that arbitrary host/target combinations are possible.
5840 The primary conceptual shift is to separate the non-portable code in
5841 GDB into three categories. Host specific code is required any time GDB
5842 is compiled on that host, regardless of the target. Target specific
5843 code relates to the peculiarities of the target, but can be compiled on
5844 any host. Native specific code is everything else: it can only be
5845 built when the host and target are the same system. Child process
5846 handling and core file support are two common `native' examples.
5848 GDB's use of /proc for controlling Unix child processes is now cleaner.
5849 It has been split out into a single module under the `target_ops' vector,
5850 plus two native-dependent functions for each system that uses /proc.
5852 * New hosts supported
5854 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5855 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5856 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5858 * New targets supported
5860 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5861 68030 and CPU32 m68030-*-*, m68332-*-*
5863 * New native hosts supported
5865 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5866 (386bsd is not well tested yet)
5867 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5869 * New file formats supported
5871 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5872 supports reading of `a.out.adobe' object files, which are an a.out
5873 format extended with minimal information about multiple sections.
5877 `show copying' is the same as the old `info copying'.
5878 `show warranty' is the same as `info warrantee'.
5879 These were renamed for consistency. The old commands continue to work.
5881 `info handle' is a new alias for `info signals'.
5883 You can now define pre-command hooks, which attach arbitrary command
5884 scripts to any command. The commands in the hook will be executed
5885 prior to the user's command. You can also create a hook which will be
5886 executed whenever the program stops. See gdb.texinfo.
5890 We now deal with Cfront style name mangling, and can even extract type
5891 info from mangled symbols. GDB can automatically figure out which
5892 symbol mangling style your C++ compiler uses.
5894 Calling of methods and virtual functions has been improved as well.
5898 The crash that occured when debugging Sun Ansi-C compiled binaries is
5899 fixed. This was due to mishandling of the extra N_SO stabs output
5902 We also finally got Ultrix 4.2 running in house, and fixed core file
5903 support, with help from a dozen people on the net.
5905 John M. Farrell discovered that the reason that single-stepping was so
5906 slow on all of the Mips based platforms (primarily SGI and DEC) was
5907 that we were trying to demangle and lookup a symbol used for internal
5908 purposes on every instruction that was being stepped through. Changing
5909 the name of that symbol so that it couldn't be mistaken for a C++
5910 mangled symbol sped things up a great deal.
5912 Rich Pixley sped up symbol lookups in general by getting much smarter
5913 about when C++ symbol mangling is necessary. This should make symbol
5914 completion (TAB on the command line) much faster. It's not as fast as
5915 we'd like, but it's significantly faster than gdb-4.6.
5919 A new user controllable variable 'call_scratch_address' can
5920 specify the location of a scratch area to be used when GDB
5921 calls a function in the target. This is necessary because the
5922 usual method of putting the scratch area on the stack does not work
5923 in systems that have separate instruction and data spaces.
5925 We integrated changes to support the 29k UDI (Universal Debugger
5926 Interface), but discovered at the last minute that we didn't have all
5927 of the appropriate copyright paperwork. We are working with AMD to
5928 resolve this, and hope to have it available soon.
5932 We have sped up the remote serial line protocol, especially for targets
5933 with lots of registers. It now supports a new `expedited status' ('T')
5934 message which can be used in place of the existing 'S' status message.
5935 This allows the remote stub to send only the registers that GDB
5936 needs to make a quick decision about single-stepping or conditional
5937 breakpoints, eliminating the need to fetch the entire register set for
5938 each instruction being stepped through.
5940 The GDB remote serial protocol now implements a write-through cache for
5941 registers, only re-reading the registers if the target has run.
5943 There is also a new remote serial stub for SPARC processors. You can
5944 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5945 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5946 processor with a serial port.
5950 Configure.in files have become much easier to read and modify. A new
5951 `table driven' format makes it more obvious what configurations are
5952 supported, and what files each one uses.
5956 There is a new opcodes library which will eventually contain all of the
5957 disassembly routines and opcode tables. At present, it only contains
5958 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5959 disassembler (binutils/objdump) to share these routines.
5961 The libiberty library is now copylefted under the GNU Library General
5962 Public License. This allows more liberal use, and was done so libg++
5963 can use it. This makes no difference to GDB, since the Library License
5964 grants all the rights from the General Public License.
5968 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5969 reference to the stabs symbol info used by the debugger. It is (as far
5970 as we know) the only published document on this fascinating topic. We
5971 encourage you to read it, compare it to the stabs information on your
5972 system, and send improvements on the document in general (to
5973 bug-gdb@prep.ai.mit.edu).
5975 And, of course, many bugs have been fixed.
5978 *** Changes in GDB-4.6:
5980 * Better support for C++ function names
5982 GDB now accepts as input the "demangled form" of C++ overloaded function
5983 names and member function names, and can do command completion on such names
5984 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5985 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5986 Make use of command completion, it is your friend.
5988 GDB also now accepts a variety of C++ mangled symbol formats. They are
5989 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5990 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5991 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5992 for the list of formats.
5994 * G++ symbol mangling problem
5996 Recent versions of gcc have a bug in how they emit debugging information for
5997 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5998 directory) can be applied to gcc to fix the problem. Alternatively, if you
5999 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6000 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6001 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6004 * New 'maintenance' command
6006 All of the commands related to hacking GDB internals have been moved out of
6007 the main command set, and now live behind the 'maintenance' command. This
6008 can also be abbreviated as 'mt'. The following changes were made:
6010 dump-me -> maintenance dump-me
6011 info all-breakpoints -> maintenance info breakpoints
6012 printmsyms -> maintenance print msyms
6013 printobjfiles -> maintenance print objfiles
6014 printpsyms -> maintenance print psymbols
6015 printsyms -> maintenance print symbols
6017 The following commands are new:
6019 maintenance demangle Call internal GDB demangler routine to
6020 demangle a C++ link name and prints the result.
6021 maintenance print type Print a type chain for a given symbol
6023 * Change to .gdbinit file processing
6025 We now read the $HOME/.gdbinit file before processing the argv arguments
6026 (e.g. reading symbol files or core files). This allows global parameters to
6027 be set, which will apply during the symbol reading. The ./.gdbinit is still
6028 read after argv processing.
6030 * New hosts supported
6032 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6034 GNU/Linux support i386-unknown-linux or linux
6036 We are also including code to support the HP/PA running BSD and HPUX. This
6037 is almost guaranteed not to work, as we didn't have time to test or build it
6038 for this release. We are including it so that the more adventurous (or
6039 masochistic) of you can play with it. We also had major problems with the
6040 fact that the compiler that we got from HP doesn't support the -g option.
6043 * New targets supported
6045 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6047 * More smarts about finding #include files
6049 GDB now remembers the compilation directory for all include files, and for
6050 all files from which C is generated (like yacc and lex sources). This
6051 greatly improves GDB's ability to find yacc/lex sources, and include files,
6052 especially if you are debugging your program from a directory different from
6053 the one that contains your sources.
6055 We also fixed a bug which caused difficulty with listing and setting
6056 breakpoints in include files which contain C code. (In the past, you had to
6057 try twice in order to list an include file that you hadn't looked at before.)
6059 * Interesting infernals change
6061 GDB now deals with arbitrary numbers of sections, where the symbols for each
6062 section must be relocated relative to that section's landing place in the
6063 target's address space. This work was needed to support ELF with embedded
6064 stabs used by Solaris-2.0.
6066 * Bug fixes (of course!)
6068 There have been loads of fixes for the following things:
6069 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6070 i960, stabs, DOS(GO32), procfs, etc...
6072 See the ChangeLog for details.
6074 *** Changes in GDB-4.5:
6076 * New machines supported (host and target)
6078 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6080 SGI Irix-4.x mips-sgi-irix4 or iris4
6082 * New malloc package
6084 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6085 Mmalloc is capable of handling mutiple heaps of memory. It is also
6086 capable of saving a heap to a file, and then mapping it back in later.
6087 This can be used to greatly speedup the startup of GDB by using a
6088 pre-parsed symbol table which lives in a mmalloc managed heap. For
6089 more details, please read mmalloc/mmalloc.texi.
6093 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6094 'help info proc' for details.
6096 * MIPS ecoff symbol table format
6098 The code that reads MIPS symbol table format is now supported on all hosts.
6099 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6102 * File name changes for MS-DOS
6104 Many files in the config directories have been renamed to make it easier to
6105 support GDB on MS-DOSe systems (which have very restrictive file name
6106 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6107 environment) is close to working but has some remaining problems. Note
6108 that debugging of DOS programs is not supported, due to limitations
6109 in the ``operating system'', but it can be used to host cross-debugging.
6111 * Cross byte order fixes
6113 Many fixes have been made to support cross debugging of Sparc and MIPS
6114 targets from hosts whose byte order differs.
6116 * New -mapped and -readnow options
6118 If memory-mapped files are available on your system through the 'mmap'
6119 system call, you can use the -mapped option on the `file' or
6120 `symbol-file' commands to cause GDB to write the symbols from your
6121 program into a reusable file. If the program you are debugging is
6122 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6123 Future GDB debugging sessions will notice the presence of this file,
6124 and will quickly map in symbol information from it, rather than reading
6125 the symbol table from the executable program. Using the '-mapped'
6126 option in a GDB `file' or `symbol-file' command has the same effect as
6127 starting GDB with the '-mapped' command-line option.
6129 You can cause GDB to read the entire symbol table immediately by using
6130 the '-readnow' option with any of the commands that load symbol table
6131 information (or on the GDB command line). This makes the command
6132 slower, but makes future operations faster.
6134 The -mapped and -readnow options are typically combined in order to
6135 build a `fred.syms' file that contains complete symbol information.
6136 A simple GDB invocation to do nothing but build a `.syms' file for future
6139 gdb -batch -nx -mapped -readnow programname
6141 The `.syms' file is specific to the host machine on which GDB is run.
6142 It holds an exact image of GDB's internal symbol table. It cannot be
6143 shared across multiple host platforms.
6145 * longjmp() handling
6147 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6148 siglongjmp() without losing control. This feature has not yet been ported to
6149 all systems. It currently works on many 386 platforms, all MIPS-based
6150 platforms (SGI, DECstation, etc), and Sun3/4.
6154 Preliminary work has been put in to support the new Solaris OS from Sun. At
6155 this time, it can control and debug processes, but it is not capable of
6160 As always, many many bug fixes. The major areas were with g++, and mipsread.
6161 People using the MIPS-based platforms should experience fewer mysterious
6162 crashes and trashed symbol tables.
6164 *** Changes in GDB-4.4:
6166 * New machines supported (host and target)
6168 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6170 BSD Reno on Vax vax-dec-bsd
6171 Ultrix on Vax vax-dec-ultrix
6173 * New machines supported (target)
6175 AMD 29000 embedded, using EBMON a29k-none-none
6179 GDB continues to improve its handling of C++. `References' work better.
6180 The demangler has also been improved, and now deals with symbols mangled as
6181 per the Annotated C++ Reference Guide.
6183 GDB also now handles `stabs' symbol information embedded in MIPS
6184 `ecoff' symbol tables. Since the ecoff format was not easily
6185 extensible to handle new languages such as C++, this appeared to be a
6186 good way to put C++ debugging info into MIPS binaries. This option
6187 will be supported in the GNU C compiler, version 2, when it is
6190 * New features for SVR4
6192 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6193 shared libraries. Debugging dynamically linked programs should present
6194 only minor differences from debugging statically linked programs.
6196 The `info proc' command will print out information about any process
6197 on an SVR4 system (including the one you are debugging). At the moment,
6198 it prints the address mappings of the process.
6200 If you bring up GDB on another SVR4 system, please send mail to
6201 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6203 * Better dynamic linking support in SunOS
6205 Reading symbols from shared libraries which contain debugging symbols
6206 now works properly. However, there remain issues such as automatic
6207 skipping of `transfer vector' code during function calls, which
6208 make it harder to debug code in a shared library, than to debug the
6209 same code linked statically.
6213 GDB is now using the latest `getopt' routines from the FSF. This
6214 version accepts the -- prefix for options with long names. GDB will
6215 continue to accept the old forms (-option and +option) as well.
6216 Various single letter abbreviations for options have been explicity
6217 added to the option table so that they won't get overshadowed in the
6218 future by other options that begin with the same letter.
6222 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6223 Many assorted bugs have been handled. Many more remain to be handled.
6224 See the various ChangeLog files (primarily in gdb and bfd) for details.
6227 *** Changes in GDB-4.3:
6229 * New machines supported (host and target)
6231 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6232 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6233 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6235 * Almost SCO Unix support
6237 We had hoped to support:
6238 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6239 (except for core file support), but we discovered very late in the release
6240 that it has problems with process groups that render gdb unusable. Sorry
6241 about that. I encourage people to fix it and post the fixes.
6243 * Preliminary ELF and DWARF support
6245 GDB can read ELF object files on System V Release 4, and can handle
6246 debugging records for C, in DWARF format, in ELF files. This support
6247 is preliminary. If you bring up GDB on another SVR4 system, please
6248 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6253 GDB now uses the latest `readline' library. One user-visible change
6254 is that two tabs will list possible command completions, which previously
6255 required typing M-? (meta-question mark, or ESC ?).
6259 The `stepi' bug that many of you noticed has been squashed.
6260 Many bugs in C++ have been handled. Many more remain to be handled.
6261 See the various ChangeLog files (primarily in gdb and bfd) for details.
6263 * State of the MIPS world (in case you wondered):
6265 GDB can understand the symbol tables emitted by the compilers
6266 supplied by most vendors of MIPS-based machines, including DEC. These
6267 symbol tables are in a format that essentially nobody else uses.
6269 Some versions of gcc come with an assembler post-processor called
6270 mips-tfile. This program is required if you want to do source-level
6271 debugging of gcc-compiled programs. I believe FSF does not ship
6272 mips-tfile with gcc version 1, but it will eventually come with gcc
6275 Debugging of g++ output remains a problem. g++ version 1.xx does not
6276 really support it at all. (If you're lucky, you should be able to get
6277 line numbers and stack traces to work, but no parameters or local
6278 variables.) With some work it should be possible to improve the
6281 When gcc version 2 is released, you will have somewhat better luck.
6282 However, even then you will get confusing results for inheritance and
6285 We will eventually provide full debugging of g++ output on
6286 DECstations. This will probably involve some kind of stabs-in-ecoff
6287 encapulation, but the details have not been worked out yet.
6290 *** Changes in GDB-4.2:
6292 * Improved configuration
6294 Only one copy of `configure' exists now, and it is not self-modifying.
6295 Porting BFD is simpler.
6299 The `step' and `next' commands now only stop at the first instruction
6300 of a source line. This prevents the multiple stops that used to occur
6301 in switch statements, for-loops, etc. `Step' continues to stop if a
6302 function that has debugging information is called within the line.
6306 Lots of small bugs fixed. More remain.
6308 * New host supported (not target)
6310 Intel 386 PC clone running Mach i386-none-mach
6313 *** Changes in GDB-4.1:
6315 * Multiple source language support
6317 GDB now has internal scaffolding to handle several source languages.
6318 It determines the type of each source file from its filename extension,
6319 and will switch expression parsing and number formatting to match the
6320 language of the function in the currently selected stack frame.
6321 You can also specifically set the language to be used, with
6322 `set language c' or `set language modula-2'.
6326 GDB now has preliminary support for the GNU Modula-2 compiler,
6327 currently under development at the State University of New York at
6328 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6329 continue through the fall of 1991 and into 1992.
6331 Other Modula-2 compilers are currently not supported, and attempting to
6332 debug programs compiled with them will likely result in an error as the
6333 symbol table is read. Feel free to work on it, though!
6335 There are hooks in GDB for strict type checking and range checking,
6336 in the `Modula-2 philosophy', but they do not currently work.
6340 GDB can now write to executable and core files (e.g. patch
6341 a variable's value). You must turn this switch on, specify
6342 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6343 by assigning a new value to a variable. Modifications take
6346 * Automatic SunOS shared library reading
6348 When you run your program, GDB automatically determines where its
6349 shared libraries (if any) have been loaded, and reads their symbols.
6350 The `share' command is no longer needed. This also works when
6351 examining core files.
6355 You can specify the number of lines that the `list' command shows.
6358 * New machines supported (host and target)
6360 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6361 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6362 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6364 * New hosts supported (not targets)
6366 IBM RT/PC: romp-ibm-aix or rtpc
6368 * New targets supported (not hosts)
6370 AMD 29000 embedded with COFF a29k-none-coff
6371 AMD 29000 embedded with a.out a29k-none-aout
6372 Ultracomputer remote kernel debug a29k-nyu-kern
6374 * New remote interfaces
6380 *** Changes in GDB-4.0:
6384 Wide output is wrapped at good places to make the output more readable.
6386 Gdb now supports cross-debugging from a host machine of one type to a
6387 target machine of another type. Communication with the target system
6388 is over serial lines. The ``target'' command handles connecting to the
6389 remote system; the ``load'' command will download a program into the
6390 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6391 also supports debugging of realtime processes running under VxWorks,
6392 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6393 stub on the target system.
6395 New CPUs supported include the AMD 29000 and Intel 960.
6397 GDB now reads object files and symbol tables via a ``binary file''
6398 library, which allows a single copy of GDB to debug programs of multiple
6399 object file types such as a.out and coff.
6401 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6402 refcard.dvi and refcard.ps are available to format it).
6405 * Control-Variable user interface simplified
6407 All variables that control the operation of the debugger can be set
6408 by the ``set'' command, and displayed by the ``show'' command.
6410 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6411 ``Show prompt'' produces the response:
6412 Gdb's prompt is new-gdb=>.
6414 What follows are the NEW set commands. The command ``help set'' will
6415 print a complete list of old and new set commands. ``help set FOO''
6416 will give a longer description of the variable FOO. ``show'' will show
6417 all of the variable descriptions and their current settings.
6419 confirm on/off: Enables warning questions for operations that are
6420 hard to recover from, e.g. rerunning the program while
6421 it is already running. Default is ON.
6423 editing on/off: Enables EMACS style command line editing
6424 of input. Previous lines can be recalled with
6425 control-P, the current line can be edited with control-B,
6426 you can search for commands with control-R, etc.
6429 history filename NAME: NAME is where the gdb command history
6430 will be stored. The default is .gdb_history,
6431 or the value of the environment variable
6434 history size N: The size, in commands, of the command history. The
6435 default is 256, or the value of the environment variable
6438 history save on/off: If this value is set to ON, the history file will
6439 be saved after exiting gdb. If set to OFF, the
6440 file will not be saved. The default is OFF.
6442 history expansion on/off: If this value is set to ON, then csh-like
6443 history expansion will be performed on
6444 command line input. The default is OFF.
6446 radix N: Sets the default radix for input and output. It can be set
6447 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6448 in the current radix, so "set radix 10" is always a no-op.
6450 height N: This integer value is the number of lines on a page. Default
6451 is 24, the current `stty rows'' setting, or the ``li#''
6452 setting from the termcap entry matching the environment
6455 width N: This integer value is the number of characters on a line.
6456 Default is 80, the current `stty cols'' setting, or the ``co#''
6457 setting from the termcap entry matching the environment
6460 Note: ``set screensize'' is obsolete. Use ``set height'' and
6461 ``set width'' instead.
6463 print address on/off: Print memory addresses in various command displays,
6464 such as stack traces and structure values. Gdb looks
6465 more ``symbolic'' if you turn this off; it looks more
6466 ``machine level'' with it on. Default is ON.
6468 print array on/off: Prettyprint arrays. New convenient format! Default
6471 print demangle on/off: Print C++ symbols in "source" form if on,
6474 print asm-demangle on/off: Same, for assembler level printouts
6477 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6480 * Support for Epoch Environment.
6482 The epoch environment is a version of Emacs v18 with windowing. One
6483 new command, ``inspect'', is identical to ``print'', except that if you
6484 are running in the epoch environment, the value is printed in its own
6488 * Support for Shared Libraries
6490 GDB can now debug programs and core files that use SunOS shared libraries.
6491 Symbols from a shared library cannot be referenced
6492 before the shared library has been linked with the program (this
6493 happens after you type ``run'' and before the function main() is entered).
6494 At any time after this linking (including when examining core files
6495 from dynamically linked programs), gdb reads the symbols from each
6496 shared library when you type the ``sharedlibrary'' command.
6497 It can be abbreviated ``share''.
6499 sharedlibrary REGEXP: Load shared object library symbols for files
6500 matching a unix regular expression. No argument
6501 indicates to load symbols for all shared libraries.
6503 info sharedlibrary: Status of loaded shared libraries.
6508 A watchpoint stops execution of a program whenever the value of an
6509 expression changes. Checking for this slows down execution
6510 tremendously whenever you are in the scope of the expression, but is
6511 quite useful for catching tough ``bit-spreader'' or pointer misuse
6512 problems. Some machines such as the 386 have hardware for doing this
6513 more quickly, and future versions of gdb will use this hardware.
6515 watch EXP: Set a watchpoint (breakpoint) for an expression.
6517 info watchpoints: Information about your watchpoints.
6519 delete N: Deletes watchpoint number N (same as breakpoints).
6520 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6521 enable N: Re-enables watchpoint number N (same as breakpoints).
6524 * C++ multiple inheritance
6526 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6529 * C++ exception handling
6531 Gdb now supports limited C++ exception handling. Besides the existing
6532 ability to breakpoint on an exception handler, gdb can breakpoint on
6533 the raising of an exception (before the stack is peeled back to the
6536 catch FOO: If there is a FOO exception handler in the dynamic scope,
6537 set a breakpoint to catch exceptions which may be raised there.
6538 Multiple exceptions (``catch foo bar baz'') may be caught.
6540 info catch: Lists all exceptions which may be caught in the
6541 current stack frame.
6544 * Minor command changes
6546 The command ``call func (arg, arg, ...)'' now acts like the print
6547 command, except it does not print or save a value if the function's result
6548 is void. This is similar to dbx usage.
6550 The ``up'' and ``down'' commands now always print the frame they end up
6551 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6552 frames without printing.
6554 * New directory command
6556 'dir' now adds directories to the FRONT of the source search path.
6557 The path starts off empty. Source files that contain debug information
6558 about the directory in which they were compiled can be found even
6559 with an empty path; Sun CC and GCC include this information. If GDB can't
6560 find your source file in the current directory, type "dir .".
6562 * Configuring GDB for compilation
6564 For normal use, type ``./configure host''. See README or gdb.texinfo
6567 GDB now handles cross debugging. If you are remotely debugging between
6568 two different machines, type ``./configure host -target=targ''.
6569 Host is the machine where GDB will run; targ is the machine
6570 where the program that you are debugging will run.