1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.11
6 * GDBserver now supports recording btrace without maintaining an active
9 * GDB now supports a negative repeat count in the 'x' command to examine
10 memory backward from the given address. For example:
13 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
14 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
15 (gdb) x/-5i 0x0000000000400580
16 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
17 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
18 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
19 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
20 0x40057b <main(int, char**)+25>:
21 callq 0x400536 <Func1(int, char const*)>
23 * Fortran: Support structures with fields of dynamic types and
24 arrays of dynamic types.
26 * GDB now supports multibit bitfields and enums in target register
29 * New Python-based convenience function $_as_string(val), which returns
30 the textual representation of a value. This function is especially
31 useful to obtain the text label of an enum value.
33 * Intel MPX bound violation handling.
35 Segmentation faults caused by a Intel MPX boundary violation
36 now display the kind of violation (upper or lower), the memory
37 address accessed and the memory bounds, along with the usual
38 signal received and code location.
42 Program received signal SIGSEGV, Segmentation fault
43 Upper bound violation while accessing address 0x7fffffffc3b3
44 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
45 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
47 * Rust language support.
48 GDB now supports debugging programs written in the Rust programming
49 language. See https://www.rust-lang.org/ for more information about
52 * Support for running interpreters on specified input/output devices
54 GDB now supports a new mechanism that allows frontends to provide
55 fully featured GDB console views, as a better alternative to
56 building such views on top of the "-interpreter-exec console"
57 command. See the new "new-ui" command below. With that command,
58 frontends can now start GDB in the traditional command-line mode
59 running in an embedded terminal emulator widget, and create a
60 separate MI interpreter running on a specified i/o device. In this
61 way, GDB handles line editing, history, tab completion, etc. in the
62 console all by itself, and the GUI uses the separate MI interpreter
63 for its own control and synchronization, invisible to the command
66 * The "catch syscall" command catches groups of related syscalls.
68 The "catch syscall" command now supports catching a group of related
69 syscalls using the 'group:' or 'g:' prefix.
74 skip -gfile file-glob-pattern
75 skip -function function
76 skip -rfunction regular-expression
77 A generalized form of the skip command, with new support for
78 glob-style file names and regular expressions for function names.
79 Additionally, a file spec and a function spec may now be combined.
81 maint info line-table REGEXP
82 Display the contents of GDB's internal line table data struture.
85 Run any GDB unit tests that were compiled in.
88 Start a new user interface instance running INTERP as interpreter,
89 using the TTY file for input/output.
93 ** gdb.Breakpoint objects have a new attribute "pending", which
94 indicates whether the breakpoint is pending.
97 Signal ("set") the given MS-Windows event object. This is used in
98 conjunction with the Windows JIT debugging (AeDebug) support, where
99 the OS suspends a crashing process until a debugger can attach to
100 it. Resuming the crashing process, in order to debug it, is done by
103 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
104 was added in GDBserver, including JIT compiling fast tracepoint's
105 conditional expression bytecode into native code.
107 * Support for various remote target protocols and ROM monitors has
110 target m32rsdi Remote M32R debugging over SDI
111 target mips MIPS remote debugging protocol
112 target pmon PMON ROM monitor
113 target ddb NEC's DDB variant of PMON for Vr4300
114 target rockhopper NEC RockHopper variant of PMON
115 target lsi LSI variant of PMO
117 * Support for tracepoints and fast tracepoints on powerpc-linux,
118 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
119 including JIT compiling fast tracepoint's conditional expression
120 bytecode into native code.
122 * MI async record =record-started now includes the method and format used for
123 recording. For example:
125 =record-started,thread-group="i1",method="btrace",format="bts"
129 Andes NDS32 nds32*-*-elf
131 *** Changes in GDB 7.11
133 * GDB now supports debugging kernel-based threads on FreeBSD.
135 * Per-inferior thread numbers
137 Thread numbers are now per inferior instead of global. If you're
138 debugging multiple inferiors, GDB displays thread IDs using a
139 qualified INF_NUM.THR_NUM form. For example:
143 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
144 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
145 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
146 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
148 As consequence, thread numbers as visible in the $_thread
149 convenience variable and in Python's InferiorThread.num attribute
150 are no longer unique between inferiors.
152 GDB now maintains a second thread ID per thread, referred to as the
153 global thread ID, which is the new equivalent of thread numbers in
154 previous releases. See also $_gthread below.
156 For backwards compatibility, MI's thread IDs always refer to global
159 * Commands that accept thread IDs now accept the qualified
160 INF_NUM.THR_NUM form as well. For example:
163 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
166 * In commands that accept a list of thread IDs, you can now refer to
167 all threads of an inferior using a star wildcard. GDB accepts
168 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
169 refer to all threads of the current inferior. For example, "info
172 * You can use "info threads -gid" to display the global thread ID of
175 * The new convenience variable $_gthread holds the global number of
178 * The new convenience variable $_inferior holds the number of the
181 * GDB now displays the ID and name of the thread that hit a breakpoint
182 or received a signal, if your program is multi-threaded. For
185 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
186 Thread 1 "main" received signal SIGINT, Interrupt.
188 * Record btrace now supports non-stop mode.
190 * Support for tracepoints on aarch64-linux was added in GDBserver.
192 * The 'record instruction-history' command now indicates speculative execution
193 when using the Intel Processor Trace recording format.
195 * GDB now allows users to specify explicit locations, bypassing
196 the linespec parser. This feature is also available to GDB/MI
199 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
200 GDB now is able to debug both AArch64 applications and ARM applications
203 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
204 including JIT compiling fast tracepoint's conditional expression bytecode
207 * GDB now supports displaced stepping on AArch64 GNU/Linux.
209 * "info threads", "info inferiors", "info display", "info checkpoints"
210 and "maint info program-spaces" now list the corresponding items in
211 ascending ID order, for consistency with all other "info" commands.
213 * In Ada, the overloads selection menu has been enhanced to display the
214 parameter types and the return types for the matching overloaded subprograms.
218 maint set target-non-stop (on|off|auto)
219 maint show target-non-stop
220 Control whether GDB targets always operate in non-stop mode even if
221 "set non-stop" is "off". The default is "auto", meaning non-stop
222 mode is enabled if supported by the target.
224 maint set bfd-sharing
225 maint show bfd-sharing
226 Control the reuse of bfd objects.
230 Control display of debugging info regarding bfd caching.
234 Control display of debugging info regarding FreeBSD threads.
236 set remote multiprocess-extensions-packet
237 show remote multiprocess-extensions-packet
238 Set/show the use of the remote protocol multiprocess extensions.
240 set remote thread-events
241 show remote thread-events
242 Set/show the use of thread create/exit events.
244 set ada print-signatures on|off
245 show ada print-signatures"
246 Control whether parameter types and return types are displayed in overloads
247 selection menus. It is activaled (@code{on}) by default.
251 Controls the maximum size of memory, in bytes, that GDB will
252 allocate for value contents. Prevents incorrect programs from
253 causing GDB to allocate overly large buffers. Default is 64k.
255 * The "disassemble" command accepts a new modifier: /s.
256 It prints mixed source+disassembly like /m with two differences:
257 - disassembled instructions are now printed in program order, and
258 - and source for all relevant files is now printed.
259 The "/m" option is now considered deprecated: its "source-centric"
260 output hasn't proved useful in practice.
262 * The "record instruction-history" command accepts a new modifier: /s.
263 It behaves exactly like /m and prints mixed source+disassembly.
265 * The "set scheduler-locking" command supports a new mode "replay".
266 It behaves like "off" in record mode and like "on" in replay mode.
268 * Support for various ROM monitors has been removed:
270 target dbug dBUG ROM monitor for Motorola ColdFire
271 target picobug Motorola picobug monitor
272 target dink32 DINK32 ROM monitor for PowerPC
273 target m32r Renesas M32R/D ROM monitor
274 target mon2000 mon2000 ROM monitor
275 target ppcbug PPCBUG ROM monitor for PowerPC
277 * Support for reading/writing memory and extracting values on architectures
278 whose memory is addressable in units of any integral multiple of 8 bits.
283 Indicates that an exec system call was executed.
285 exec-events feature in qSupported
286 The qSupported packet allows GDB to request support for exec
287 events using the new 'gdbfeature' exec-event, and the qSupported
288 response can contain the corresponding 'stubfeature'. Set and
289 show commands can be used to display whether these features are enabled.
292 Equivalent to interrupting with the ^C character, but works in
295 thread created stop reason (T05 create:...)
296 Indicates that the thread was just created and is stopped at entry.
298 thread exit stop reply (w exitcode;tid)
299 Indicates that the thread has terminated.
302 Enables/disables thread create and exit event reporting. For
303 example, this is used in non-stop mode when GDB stops a set of
304 threads and synchronously waits for the their corresponding stop
305 replies. Without exit events, if one of the threads exits, GDB
306 would hang forever not knowing that it should no longer expect a
307 stop for that same thread.
310 Indicates that there are no resumed threads left in the target (all
311 threads are stopped). The remote stub reports support for this stop
312 reply to GDB's qSupported query.
315 Enables/disables catching syscalls from the inferior process.
316 The remote stub reports support for this packet to GDB's qSupported query.
318 syscall_entry stop reason
319 Indicates that a syscall was just called.
321 syscall_return stop reason
322 Indicates that a syscall just returned.
324 * Extended-remote exec events
326 ** GDB now has support for exec events on extended-remote Linux targets.
327 For such targets with Linux kernels 2.5.46 and later, this enables
328 follow-exec-mode and exec catchpoints.
330 set remote exec-event-feature-packet
331 show remote exec-event-feature-packet
332 Set/show the use of the remote exec event feature.
334 * Thread names in remote protocol
336 The reply to qXfer:threads:read may now include a name attribute for each
339 * Target remote mode fork and exec events
341 ** GDB now has support for fork and exec events on target remote mode
342 Linux targets. For such targets with Linux kernels 2.5.46 and later,
343 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
344 fork and exec catchpoints.
346 * Remote syscall events
348 ** GDB now has support for catch syscall on remote Linux targets,
349 currently enabled on x86/x86_64 architectures.
351 set remote catch-syscall-packet
352 show remote catch-syscall-packet
353 Set/show the use of the remote catch syscall feature.
357 ** The -var-set-format command now accepts the zero-hexadecimal
358 format. It outputs data in hexadecimal format with zero-padding on the
363 ** gdb.InferiorThread objects have a new attribute "global_num",
364 which refers to the thread's global thread ID. The existing
365 "num" attribute now refers to the thread's per-inferior number.
366 See "Per-inferior thread numbers" above.
367 ** gdb.InferiorThread objects have a new attribute "inferior", which
368 is the Inferior object the thread belongs to.
370 *** Changes in GDB 7.10
372 * Support for process record-replay and reverse debugging on aarch64*-linux*
373 targets has been added. GDB now supports recording of A64 instruction set
374 including advance SIMD instructions.
376 * Support for Sun's version of the "stabs" debug file format has been removed.
378 * GDB now honors the content of the file /proc/PID/coredump_filter
379 (PID is the process ID) on GNU/Linux systems. This file can be used
380 to specify the types of memory mappings that will be included in a
381 corefile. For more information, please refer to the manual page of
382 "core(5)". GDB also has a new command: "set use-coredump-filter
383 on|off". It allows to set whether GDB will read the content of the
384 /proc/PID/coredump_filter file when generating a corefile.
386 * The "info os" command on GNU/Linux can now display information on
388 "info os cpus" Listing of all cpus/cores on the system
390 * GDB has two new commands: "set serial parity odd|even|none" and
391 "show serial parity". These allows to set or show parity for the
394 * The "info source" command now displays the producer string if it was
395 present in the debug info. This typically includes the compiler version
396 and may include things like its command line arguments.
398 * The "info dll", an alias of the "info sharedlibrary" command,
399 is now available on all platforms.
401 * Directory names supplied to the "set sysroot" commands may be
402 prefixed with "target:" to tell GDB to access shared libraries from
403 the target system, be it local or remote. This replaces the prefix
404 "remote:". The default sysroot has been changed from "" to
405 "target:". "remote:" is automatically converted to "target:" for
406 backward compatibility.
408 * The system root specified by "set sysroot" will be prepended to the
409 filename of the main executable (if reported to GDB as absolute by
410 the operating system) when starting processes remotely, and when
411 attaching to already-running local or remote processes.
413 * GDB now supports automatic location and retrieval of executable
414 files from remote targets. Remote debugging can now be initiated
415 using only a "target remote" or "target extended-remote" command
416 (no "set sysroot" or "file" commands are required). See "New remote
419 * The "dump" command now supports verilog hex format.
421 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
423 * On GNU/Linux, GDB and gdbserver are now able to access executable
424 and shared library files without a "set sysroot" command when
425 attaching to processes running in different mount namespaces from
426 the debugger. This makes it possible to attach to processes in
427 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
428 See "New remote packets" below.
430 * The "tui reg" command now provides completion for all of the
431 available register groups, including target specific groups.
433 * The HISTSIZE environment variable is no longer read when determining
434 the size of GDB's command history. GDB now instead reads the dedicated
435 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
436 disables truncation of command history. Non-numeric values of GDBHISTSIZE
441 ** Memory ports can now be unbuffered.
445 ** gdb.Objfile objects have a new attribute "username",
446 which is the name of the objfile as specified by the user,
447 without, for example, resolving symlinks.
448 ** You can now write frame unwinders in Python.
449 ** gdb.Type objects have a new method "optimized_out",
450 returning optimized out gdb.Value instance of this type.
451 ** gdb.Value objects have new methods "reference_value" and
452 "const_value" which return a reference to the value and a
453 "const" version of the value respectively.
457 maint print symbol-cache
458 Print the contents of the symbol cache.
460 maint print symbol-cache-statistics
461 Print statistics of symbol cache usage.
463 maint flush-symbol-cache
464 Flush the contents of the symbol cache.
468 Start branch trace recording using Branch Trace Store (BTS) format.
471 Evaluate expression by using the compiler and print result.
475 Explicit commands for enabling and disabling tui mode.
478 set mpx bound on i386 and amd64
479 Support for bound table investigation on Intel MPX enabled applications.
483 Start branch trace recording using Intel Processor Trace format.
486 Print information about branch tracing internals.
488 maint btrace packet-history
489 Print the raw branch tracing data.
491 maint btrace clear-packet-history
492 Discard the stored raw branch tracing data.
495 Discard all branch tracing data. It will be fetched and processed
496 anew by the next "record" command.
501 Renamed from "set debug dwarf2-die".
503 Renamed from "show debug dwarf2-die".
506 Renamed from "set debug dwarf2-read".
507 show debug dwarf-read
508 Renamed from "show debug dwarf2-read".
510 maint set dwarf always-disassemble
511 Renamed from "maint set dwarf2 always-disassemble".
512 maint show dwarf always-disassemble
513 Renamed from "maint show dwarf2 always-disassemble".
515 maint set dwarf max-cache-age
516 Renamed from "maint set dwarf2 max-cache-age".
517 maint show dwarf max-cache-age
518 Renamed from "maint show dwarf2 max-cache-age".
521 show debug dwarf-line
522 Control display of debugging info regarding DWARF line processing.
526 Set the maximum number of candidates to be considered during
527 completion. The default value is 200. This limit allows GDB
528 to avoid generating large completion lists, the computation of
529 which can cause the debugger to become temporarily unresponsive.
531 set history remove-duplicates
532 show history remove-duplicates
533 Control the removal of duplicate history entries.
535 maint set symbol-cache-size
536 maint show symbol-cache-size
537 Control the size of the symbol cache.
539 set|show record btrace bts buffer-size
540 Set and show the size of the ring buffer used for branch tracing in
542 The obtained size may differ from the requested size. Use "info
543 record" to see the obtained buffer size.
545 set debug linux-namespaces
546 show debug linux-namespaces
547 Control display of debugging info regarding Linux namespaces.
549 set|show record btrace pt buffer-size
550 Set and show the size of the ring buffer used for branch tracing in
551 Intel Processor Trace format.
552 The obtained size may differ from the requested size. Use "info
553 record" to see the obtained buffer size.
555 maint set|show btrace pt skip-pad
556 Set and show whether PAD packets are skipped when computing the
559 * The command 'thread apply all' can now support new option '-ascending'
560 to call its specified command for all threads in ascending order.
562 * Python/Guile scripting
564 ** GDB now supports auto-loading of Python/Guile scripts contained in the
565 special section named `.debug_gdb_scripts'.
569 qXfer:btrace-conf:read
570 Return the branch trace configuration for the current thread.
572 Qbtrace-conf:bts:size
573 Set the requested ring buffer size for branch tracing in BTS format.
576 Enable Intel Procesor Trace-based branch tracing for the current
577 process. The remote stub reports support for this packet to GDB's
581 Set the requested ring buffer size for branch tracing in Intel Processor
585 Indicates a memory breakpoint instruction was executed, irrespective
586 of whether it was GDB that planted the breakpoint or the breakpoint
587 is hardcoded in the program. This is required for correct non-stop
591 Indicates the target stopped for a hardware breakpoint. This is
592 required for correct non-stop mode operation.
595 Return information about files on the remote system.
598 Return the full absolute name of the file that was executed to
599 create a process running on the remote system.
602 Select the filesystem on which vFile: operations with filename
603 arguments will operate. This is required for GDB to be able to
604 access files on remote targets where the remote stub does not
605 share a common filesystem with the inferior(s).
608 Indicates that a fork system call was executed.
611 Indicates that a vfork system call was executed.
613 vforkdone stop reason
614 Indicates that a vfork child of the specified process has executed
615 an exec or exit, allowing the vfork parent to resume execution.
617 fork-events and vfork-events features in qSupported
618 The qSupported packet allows GDB to request support for fork and
619 vfork events using new 'gdbfeatures' fork-events and vfork-events,
620 and the qSupported response can contain the corresponding
621 'stubfeatures'. Set and show commands can be used to display
622 whether these features are enabled.
624 * Extended-remote fork events
626 ** GDB now has support for fork events on extended-remote Linux
627 targets. For targets with Linux kernels 2.5.60 and later, this
628 enables follow-fork-mode and detach-on-fork for both fork and
629 vfork, as well as fork and vfork catchpoints.
631 * The info record command now shows the recording format and the
632 branch tracing configuration for the current thread when using
633 the btrace record target.
634 For the BTS format, it shows the ring buffer size.
636 * GDB now has support for DTrace USDT (Userland Static Defined
637 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
639 * GDB now supports access to vector registers on S/390 GNU/Linux
642 * Removed command line options
644 -xdb HP-UX XDB compatibility mode.
646 * Removed targets and native configurations
648 HP/PA running HP-UX hppa*-*-hpux*
649 Itanium running HP-UX ia64-*-hpux*
651 * New configure options
654 This configure option allows the user to build GDB with support for
655 Intel Processor Trace (default: auto). This requires libipt.
657 --with-libipt-prefix=PATH
658 Specify the path to the version of libipt that GDB should use.
659 $PATH/include should contain the intel-pt.h header and
660 $PATH/lib should contain the libipt.so library.
662 *** Changes in GDB 7.9.1
666 ** Xmethods can now specify a result type.
668 *** Changes in GDB 7.9
670 * GDB now supports hardware watchpoints on x86 GNU Hurd.
674 ** You can now access frame registers from Python scripts.
675 ** New attribute 'producer' for gdb.Symtab objects.
676 ** gdb.Objfile objects have a new attribute "progspace",
677 which is the gdb.Progspace object of the containing program space.
678 ** gdb.Objfile objects have a new attribute "owner".
679 ** gdb.Objfile objects have a new attribute "build_id",
680 which is the build ID generated when the file was built.
681 ** gdb.Objfile objects have a new method "add_separate_debug_file".
682 ** A new event "gdb.clear_objfiles" has been added, triggered when
683 selecting a new file to debug.
684 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
685 ** New function gdb.lookup_objfile.
687 New events which are triggered when GDB modifies the state of the
690 ** gdb.events.inferior_call_pre: Function call is about to be made.
691 ** gdb.events.inferior_call_post: Function call has just been made.
692 ** gdb.events.memory_changed: A memory location has been altered.
693 ** gdb.events.register_changed: A register has been altered.
695 * New Python-based convenience functions:
697 ** $_caller_is(name [, number_of_frames])
698 ** $_caller_matches(regexp [, number_of_frames])
699 ** $_any_caller_is(name [, number_of_frames])
700 ** $_any_caller_matches(regexp [, number_of_frames])
702 * GDB now supports the compilation and injection of source code into
703 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
704 to compile the source code to object code, and if successful, inject
705 and execute that code within the current context of the inferior.
706 Currently the C language is supported. The commands used to
707 interface with this new feature are:
709 compile code [-raw|-r] [--] [source code]
710 compile file [-raw|-r] filename
714 demangle [-l language] [--] name
715 Demangle "name" in the specified language, or the current language
716 if elided. This command is renamed from the "maint demangle" command.
717 The latter is kept as a no-op to avoid "maint demangle" being interpreted
718 as "maint demangler-warning".
720 queue-signal signal-name-or-number
721 Queue a signal to be delivered to the thread when it is resumed.
723 add-auto-load-scripts-directory directory
724 Add entries to the list of directories from which to load auto-loaded
727 maint print user-registers
728 List all currently available "user" registers.
730 compile code [-r|-raw] [--] [source code]
731 Compile, inject, and execute in the inferior the executable object
732 code produced by compiling the provided source code.
734 compile file [-r|-raw] filename
735 Compile and inject into the inferior the executable object code
736 produced by compiling the source code stored in the filename
739 * On resume, GDB now always passes the signal the program had stopped
740 for to the thread the signal was sent to, even if the user changed
741 threads before resuming. Previously GDB would often (but not
742 always) deliver the signal to the thread that happens to be current
745 * Conversely, the "signal" command now consistently delivers the
746 requested signal to the current thread. GDB now asks for
747 confirmation if the program had stopped for a signal and the user
748 switched threads meanwhile.
750 * "breakpoint always-inserted" modes "off" and "auto" merged.
752 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
753 won't remove breakpoints from the target until all threads stop,
754 even in non-stop mode. The "auto" mode has been removed, and "off"
755 is now the default mode.
759 set debug symbol-lookup
760 show debug symbol-lookup
761 Control display of debugging info regarding symbol lookup.
765 ** The -list-thread-groups command outputs an exit-code field for
766 inferiors that have exited.
770 MIPS SDE mips*-sde*-elf*
774 Support for these obsolete configurations has been removed.
776 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
777 SGI Irix-5.x mips-*-irix5*
778 SGI Irix-6.x mips-*-irix6*
779 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
780 VAX running Ultrix vax-*-ultrix*
782 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
783 and "assf"), have been removed. Use the "sharedlibrary" command, or
784 its alias "share", instead.
786 *** Changes in GDB 7.8
788 * New command line options
791 This is an alias for the --data-directory option.
793 * GDB supports printing and modifying of variable length automatic arrays
794 as specified in ISO C99.
796 * The ARM simulator now supports instruction level tracing
797 with or without disassembly.
801 GDB now has support for scripting using Guile. Whether this is
802 available is determined at configure time.
803 Guile version 2.0 or greater is required.
804 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
806 * New commands (for set/show, see "New options" below)
810 Invoke CODE by passing it to the Guile interpreter.
814 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
816 info auto-load guile-scripts [regexp]
817 Print the list of automatically loaded Guile scripts.
819 * The source command is now capable of sourcing Guile scripts.
820 This feature is dependent on the debugger being built with Guile support.
824 set print symbol-loading (off|brief|full)
825 show print symbol-loading
826 Control whether to print informational messages when loading symbol
827 information for a file. The default is "full", but when debugging
828 programs with large numbers of shared libraries the amount of output
831 set guile print-stack (none|message|full)
832 show guile print-stack
833 Show a stack trace when an error is encountered in a Guile script.
835 set auto-load guile-scripts (on|off)
836 show auto-load guile-scripts
837 Control auto-loading of Guile script files.
839 maint ada set ignore-descriptive-types (on|off)
840 maint ada show ignore-descriptive-types
841 Control whether the debugger should ignore descriptive types in Ada
842 programs. The default is not to ignore the descriptive types. See
843 the user manual for more details on descriptive types and the intended
844 usage of this option.
846 set auto-connect-native-target
848 Control whether GDB is allowed to automatically connect to the
849 native target for the run, attach, etc. commands when not connected
850 to any target yet. See also "target native" below.
852 set record btrace replay-memory-access (read-only|read-write)
853 show record btrace replay-memory-access
854 Control what memory accesses are allowed during replay.
856 maint set target-async (on|off)
857 maint show target-async
858 This controls whether GDB targets operate in synchronous or
859 asynchronous mode. Normally the default is asynchronous, if it is
860 available; but this can be changed to more easily debug problems
861 occurring only in synchronous mode.
863 set mi-async (on|off)
865 Control whether MI asynchronous mode is preferred. This supersedes
866 "set target-async" of previous GDB versions.
868 * "set target-async" is deprecated as a CLI option and is now an alias
869 for "set mi-async" (only puts MI into async mode).
871 * Background execution commands (e.g., "c&", "s&", etc.) are now
872 possible ``out of the box'' if the target supports them. Previously
873 the user would need to explicitly enable the possibility with the
874 "set target-async on" command.
876 * New features in the GDB remote stub, GDBserver
878 ** New option --debug-format=option1[,option2,...] allows one to add
879 additional text to each output. At present only timestamps
880 are supported: --debug-format=timestamps.
881 Timestamps can also be turned on with the
882 "monitor set debug-format timestamps" command from GDB.
884 * The 'record instruction-history' command now starts counting instructions
885 at one. This also affects the instruction ranges reported by the
886 'record function-call-history' command when given the /i modifier.
888 * The command 'record function-call-history' supports a new modifier '/c' to
889 indent the function names based on their call stack depth.
890 The fields for the '/i' and '/l' modifier have been reordered.
891 The source line range is now prefixed with 'at'.
892 The instruction range is now prefixed with 'inst'.
893 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
894 "record instruction-history" and "list" commands.
896 * The ranges given as arguments to the 'record function-call-history' and
897 'record instruction-history' commands are now inclusive.
899 * The btrace record target now supports the 'record goto' command.
900 For locations inside the execution trace, the back trace is computed
901 based on the information stored in the execution trace.
903 * The btrace record target supports limited reverse execution and replay.
904 The target does not record data and therefore does not allow reading
907 * The "catch syscall" command now works on s390*-linux* targets.
909 * The "compare-sections" command is no longer specific to target
910 remote. It now works with all targets.
912 * All native targets are now consistently called "native".
913 Consequently, the "target child", "target GNU", "target djgpp",
914 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
915 commands have been replaced with "target native". The QNX/NTO port
916 leaves the "procfs" target in place and adds a "native" target for
917 consistency with other ports. The impact on users should be minimal
918 as these commands previously either throwed an error, or were
919 no-ops. The target's name is visible in the output of the following
920 commands: "help target", "info target", "info files", "maint print
923 * The "target native" command now connects to the native target. This
924 can be used to launch native programs even when "set
925 auto-connect-native-target" is set to off.
927 * GDB now supports access to Intel MPX registers on GNU/Linux.
929 * Support for Intel AVX-512 registers on GNU/Linux.
930 Support displaying and modifying Intel AVX-512 registers
931 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
935 qXfer:btrace:read's annex
936 The qXfer:btrace:read packet supports a new annex 'delta' to read
937 branch trace incrementally.
941 ** Valid Python operations on gdb.Value objects representing
942 structs/classes invoke the corresponding overloaded operators if
944 ** New `Xmethods' feature in the Python API. Xmethods are
945 additional methods or replacements for existing methods of a C++
946 class. This feature is useful for those cases where a method
947 defined in C++ source code could be inlined or optimized out by
948 the compiler, making it unavailable to GDB.
951 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
953 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
954 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
955 its alias "share", instead.
957 * The commands "set remotebaud" and "show remotebaud" are no longer
958 supported. Use "set serial baud" and "show serial baud" (respectively)
963 ** A new option "-gdb-set mi-async" replaces "-gdb-set
964 target-async". The latter is left as a deprecated alias of the
965 former for backward compatibility. If the target supports it,
966 CLI background execution commands are now always possible by
967 default, independently of whether the frontend stated a
968 preference for asynchronous execution with "-gdb-set mi-async".
969 Previously "-gdb-set target-async off" affected both MI execution
970 commands and CLI execution commands.
972 *** Changes in GDB 7.7
974 * Improved support for process record-replay and reverse debugging on
975 arm*-linux* targets. Support for thumb32 and syscall instruction
976 recording has been added.
978 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
980 * GDB now supports Fission DWP file format version 2.
981 http://gcc.gnu.org/wiki/DebugFission
983 * New convenience function "$_isvoid", to check whether an expression
984 is void. A void expression is an expression where the type of the
985 result is "void". For example, some convenience variables may be
986 "void" when evaluated (e.g., "$_exitcode" before the execution of
987 the program being debugged; or an undefined convenience variable).
988 Another example, when calling a function whose return type is
991 * The "maintenance print objfiles" command now takes an optional regexp.
993 * The "catch syscall" command now works on arm*-linux* targets.
995 * GDB now consistently shows "<not saved>" when printing values of
996 registers the debug info indicates have not been saved in the frame
997 and there's nowhere to retrieve them from
998 (callee-saved/call-clobbered registers):
1003 (gdb) info registers rax
1006 Before, the former would print "<optimized out>", and the latter
1007 "*value not available*".
1009 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1014 ** Frame filters and frame decorators have been added.
1015 ** Temporary breakpoints are now supported.
1016 ** Line tables representation has been added.
1017 ** New attribute 'parent_type' for gdb.Field objects.
1018 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1019 ** New attribute 'name' for gdb.Type objects.
1023 Nios II ELF nios2*-*-elf
1024 Nios II GNU/Linux nios2*-*-linux
1025 Texas Instruments MSP430 msp430*-*-elf
1027 * Removed native configurations
1029 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1030 been removed. ELF variants of these configurations are kept supported.
1032 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1033 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1034 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1035 i[34567]86-*-openbsd3.[0-3]
1036 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1037 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1038 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1042 Like "catch throw", but catches a re-thrown exception.
1043 maint check-psymtabs
1044 Renamed from old "maint check-symtabs".
1046 Perform consistency checks on symtabs.
1047 maint expand-symtabs
1048 Expand symtabs matching an optional regexp.
1051 Display the details of GDB configure-time options.
1053 maint set|show per-command
1054 maint set|show per-command space
1055 maint set|show per-command time
1056 maint set|show per-command symtab
1057 Enable display of per-command gdb resource usage.
1059 remove-symbol-file FILENAME
1060 remove-symbol-file -a ADDRESS
1061 Remove a symbol file added via add-symbol-file. The file to remove
1062 can be identified by its filename or by an address that lies within
1063 the boundaries of this symbol file in memory.
1066 info exceptions REGEXP
1067 Display the list of Ada exceptions defined in the program being
1068 debugged. If provided, only the exceptions whose names match REGEXP
1073 set debug symfile off|on
1075 Control display of debugging info regarding reading symbol files and
1076 symbol tables within those files
1078 set print raw frame-arguments
1079 show print raw frame-arguments
1080 Set/show whether to print frame arguments in raw mode,
1081 disregarding any defined pretty-printers.
1083 set remote trace-status-packet
1084 show remote trace-status-packet
1085 Set/show the use of remote protocol qTStatus packet.
1089 Control display of debugging messages related to Nios II targets.
1093 Control whether target-assisted range stepping is enabled.
1095 set startup-with-shell
1096 show startup-with-shell
1097 Specifies whether Unix child processes are started via a shell or
1102 Use the target memory cache for accesses to the code segment. This
1103 improves performance of remote debugging (particularly disassembly).
1105 * You can now use a literal value 'unlimited' for options that
1106 interpret 0 or -1 as meaning "unlimited". E.g., "set
1107 trace-buffer-size unlimited" is now an alias for "set
1108 trace-buffer-size -1" and "set height unlimited" is now an alias for
1111 * The "set debug symtab-create" debugging option of GDB has been changed to
1112 accept a verbosity level. 0 means "off", 1 provides basic debugging
1113 output, and values of 2 or greater provides more verbose output.
1115 * New command-line options
1117 Display the details of GDB configure-time options.
1119 * The command 'tsave' can now support new option '-ctf' to save trace
1120 buffer in Common Trace Format.
1122 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1125 * GDB now implements the the C++ 'typeid' operator.
1127 * The new convenience variable $_exception holds the exception being
1128 thrown or caught at an exception-related catchpoint.
1130 * The exception-related catchpoints, like "catch throw", now accept a
1131 regular expression which can be used to filter exceptions by type.
1133 * The new convenience variable $_exitsignal is automatically set to
1134 the terminating signal number when the program being debugged dies
1135 due to an uncaught signal.
1139 ** All MI commands now accept an optional "--language" option.
1140 Support for this feature can be verified by using the "-list-features"
1141 command, which should contain "language-option".
1143 ** The new command -info-gdb-mi-command allows the user to determine
1144 whether a GDB/MI command is supported or not.
1146 ** The "^error" result record returned when trying to execute an undefined
1147 GDB/MI command now provides a variable named "code" whose content is the
1148 "undefined-command" error code. Support for this feature can be verified
1149 by using the "-list-features" command, which should contain
1150 "undefined-command-error-code".
1152 ** The -trace-save MI command can optionally save trace buffer in Common
1155 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1157 ** The command -data-list-register-values now accepts an optional
1158 "--skip-unavailable" option. When used, only the available registers
1161 ** The new command -trace-frame-collected dumps collected variables,
1162 computed expressions, tvars, memory and registers in a traceframe.
1164 ** The commands -stack-list-locals, -stack-list-arguments and
1165 -stack-list-variables now accept an option "--skip-unavailable".
1166 When used, only the available locals or arguments are displayed.
1168 ** The -exec-run command now accepts an optional "--start" option.
1169 When used, the command follows the same semantics as the "start"
1170 command, stopping the program's execution at the start of its
1171 main subprogram. Support for this feature can be verified using
1172 the "-list-features" command, which should contain
1173 "exec-run-start-option".
1175 ** The new commands -catch-assert and -catch-exceptions insert
1176 catchpoints stopping the program when Ada exceptions are raised.
1178 ** The new command -info-ada-exceptions provides the equivalent of
1179 the new "info exceptions" command.
1181 * New system-wide configuration scripts
1182 A GDB installation now provides scripts suitable for use as system-wide
1183 configuration scripts for the following systems:
1187 * GDB now supports target-assigned range stepping with remote targets.
1188 This improves the performance of stepping source lines by reducing
1189 the number of control packets from/to GDB. See "New remote packets"
1192 * GDB now understands the element 'tvar' in the XML traceframe info.
1193 It has the id of the collected trace state variables.
1195 * On S/390 targets that provide the transactional-execution feature,
1196 the program interruption transaction diagnostic block (TDB) is now
1197 represented as a number of additional "registers" in GDB.
1199 * New remote packets
1203 The vCont packet supports a new 'r' action, that tells the remote
1204 stub to step through an address range itself, without GDB
1205 involvemement at each single-step.
1207 qXfer:libraries-svr4:read's annex
1208 The previously unused annex of the qXfer:libraries-svr4:read packet
1209 is now used to support passing an argument list. The remote stub
1210 reports support for this argument list to GDB's qSupported query.
1211 The defined arguments are "start" and "prev", used to reduce work
1212 necessary for library list updating, resulting in significant
1215 * New features in the GDB remote stub, GDBserver
1217 ** GDBserver now supports target-assisted range stepping. Currently
1218 enabled on x86/x86_64 GNU/Linux targets.
1220 ** GDBserver now adds element 'tvar' in the XML in the reply to
1221 'qXfer:traceframe-info:read'. It has the id of the collected
1222 trace state variables.
1224 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1227 * New 'z' formatter for printing and examining memory, this displays the
1228 value as hexadecimal zero padded on the left to the size of the type.
1230 * GDB can now use Windows x64 unwinding data.
1232 * The "set remotebaud" command has been replaced by "set serial baud".
1233 Similarly, "show remotebaud" has been replaced by "show serial baud".
1234 The "set remotebaud" and "show remotebaud" commands are still available
1235 to provide backward compatibility with older versions of GDB.
1237 *** Changes in GDB 7.6
1239 * Target record has been renamed to record-full.
1240 Record/replay is now enabled with the "record full" command.
1241 This also affects settings that are associated with full record/replay
1242 that have been moved from "set/show record" to "set/show record full":
1244 set|show record full insn-number-max
1245 set|show record full stop-at-limit
1246 set|show record full memory-query
1248 * A new record target "record-btrace" has been added. The new target
1249 uses hardware support to record the control-flow of a process. It
1250 does not support replaying the execution, but it implements the
1251 below new commands for investigating the recorded execution log.
1252 This new recording method can be enabled using:
1256 The "record-btrace" target is only available on Intel Atom processors
1257 and requires a Linux kernel 2.6.32 or later.
1259 * Two new commands have been added for record/replay to give information
1260 about the recorded execution without having to replay the execution.
1261 The commands are only supported by "record btrace".
1263 record instruction-history prints the execution history at
1264 instruction granularity
1266 record function-call-history prints the execution history at
1267 function granularity
1269 * New native configurations
1271 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1272 FreeBSD/powerpc powerpc*-*-freebsd
1273 x86_64/Cygwin x86_64-*-cygwin*
1274 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1278 ARM AArch64 aarch64*-*-elf
1279 ARM AArch64 GNU/Linux aarch64*-*-linux
1280 Lynx 178 PowerPC powerpc-*-lynx*178
1281 x86_64/Cygwin x86_64-*-cygwin*
1282 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1284 * If the configured location of system.gdbinit file (as given by the
1285 --with-system-gdbinit option at configure time) is in the
1286 data-directory (as specified by --with-gdb-datadir at configure
1287 time) or in one of its subdirectories, then GDB will look for the
1288 system-wide init file in the directory specified by the
1289 --data-directory command-line option.
1291 * New command line options:
1293 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1294 other initialization files, unlike -nx which disables all of them.
1296 * Removed command line options
1298 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1301 * The 'ptype' and 'whatis' commands now accept an argument to control
1304 * 'info proc' now works on some core files.
1308 ** Vectors can be created with gdb.Type.vector.
1310 ** Python's atexit.register now works in GDB.
1312 ** Types can be pretty-printed via a Python API.
1314 ** Python 3 is now supported (in addition to Python 2.4 or later)
1316 ** New class gdb.Architecture exposes GDB's internal representation
1317 of architecture in the Python API.
1319 ** New method Frame.architecture returns the gdb.Architecture object
1320 corresponding to the frame's architecture.
1322 * New Python-based convenience functions:
1324 ** $_memeq(buf1, buf2, length)
1325 ** $_streq(str1, str2)
1327 ** $_regex(str, regex)
1329 * The 'cd' command now defaults to using '~' (the home directory) if not
1332 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1333 default for GCC since November 2000.
1335 * The command 'forward-search' can now be abbreviated as 'fo'.
1337 * The command 'info tracepoints' can now display 'installed on target'
1338 or 'not installed on target' for each non-pending location of tracepoint.
1340 * New configure options
1342 --enable-libmcheck/--disable-libmcheck
1343 By default, development versions are built with -lmcheck on hosts
1344 that support it, in order to help track memory corruption issues.
1345 Release versions, on the other hand, are built without -lmcheck
1346 by default. The --enable-libmcheck/--disable-libmcheck configure
1347 options allow the user to override that default.
1348 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1349 This configure option allows the user to build GDB with
1350 libbabeltrace using which GDB can read Common Trace Format data.
1352 * New commands (for set/show, see "New options" below)
1355 Catch signals. This is similar to "handle", but allows commands and
1356 conditions to be attached.
1359 List the BFDs known to GDB.
1361 python-interactive [command]
1363 Start a Python interactive prompt, or evaluate the optional command
1364 and print the result of expressions.
1367 "py" is a new alias for "python".
1369 enable type-printer [name]...
1370 disable type-printer [name]...
1371 Enable or disable type printers.
1375 ** For the Renesas Super-H architecture, the "regs" command has been removed
1376 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1381 set print type methods (on|off)
1382 show print type methods
1383 Control whether method declarations are displayed by "ptype".
1384 The default is to show them.
1386 set print type typedefs (on|off)
1387 show print type typedefs
1388 Control whether typedef definitions are displayed by "ptype".
1389 The default is to show them.
1391 set filename-display basename|relative|absolute
1392 show filename-display
1393 Control the way in which filenames is displayed.
1394 The default is "relative", which preserves previous behavior.
1396 set trace-buffer-size
1397 show trace-buffer-size
1398 Request target to change the size of trace buffer.
1400 set remote trace-buffer-size-packet auto|on|off
1401 show remote trace-buffer-size-packet
1402 Control the use of the remote protocol `QTBuffer:size' packet.
1406 Control display of debugging messages related to ARM AArch64.
1409 set debug coff-pe-read
1410 show debug coff-pe-read
1411 Control display of debugging messages related to reading of COFF/PE
1416 Control display of debugging messages related to Mach-O symbols
1419 set debug notification
1420 show debug notification
1421 Control display of debugging info for async remote notification.
1425 ** Command parameter changes are now notified using new async record
1426 "=cmd-param-changed".
1427 ** Trace frame changes caused by command "tfind" are now notified using
1428 new async record "=traceframe-changed".
1429 ** The creation, deletion and modification of trace state variables
1430 are now notified using new async records "=tsv-created",
1431 "=tsv-deleted" and "=tsv-modified".
1432 ** The start and stop of process record are now notified using new
1433 async record "=record-started" and "=record-stopped".
1434 ** Memory changes are now notified using new async record
1436 ** The data-disassemble command response will include a "fullname" field
1437 containing the absolute file name when source has been requested.
1438 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1439 command, to allow pattern filling of memory areas.
1440 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1441 library load/unload events.
1442 ** The response to breakpoint commands and breakpoint async records
1443 includes an "installed" field containing a boolean state about each
1444 non-pending tracepoint location is whether installed on target or not.
1445 ** Output of the "-trace-status" command includes a "trace-file" field
1446 containing the name of the trace file being examined. This field is
1447 optional, and only present when examining a trace file.
1448 ** The "fullname" field is now always present along with the "file" field,
1449 even if the file cannot be found by GDB.
1451 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1452 You must have the LZMA library available when configuring GDB for this
1453 feature to be enabled. For more information, see:
1454 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1456 * New remote packets
1459 Set the size of trace buffer. The remote stub reports support for this
1460 packet to gdb's qSupported query.
1463 Enable Branch Trace Store (BTS)-based branch tracing for the current
1464 thread. The remote stub reports support for this packet to gdb's
1468 Disable branch tracing for the current thread. The remote stub reports
1469 support for this packet to gdb's qSupported query.
1472 Read the traced branches for the current thread. The remote stub
1473 reports support for this packet to gdb's qSupported query.
1475 *** Changes in GDB 7.5
1477 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1478 for more x32 ABI info.
1480 * GDB now supports access to MIPS DSP registers on Linux targets.
1482 * GDB now supports debugging microMIPS binaries.
1484 * The "info os" command on GNU/Linux can now display information on
1485 several new classes of objects managed by the operating system:
1486 "info os procgroups" lists process groups
1487 "info os files" lists file descriptors
1488 "info os sockets" lists internet-domain sockets
1489 "info os shm" lists shared-memory regions
1490 "info os semaphores" lists semaphores
1491 "info os msg" lists message queues
1492 "info os modules" lists loaded kernel modules
1494 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1495 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1496 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1497 options and inspect the probe arguments using the new $_probe_arg family
1498 of convenience variables. You can obtain more information about SystemTap
1499 in <http://sourceware.org/systemtap/>.
1501 * GDB now supports reversible debugging on ARM, it allows you to
1502 debug basic ARM and THUMB instructions, and provides
1503 record/replay support.
1505 * The option "symbol-reloading" has been deleted as it is no longer used.
1509 ** GDB commands implemented in Python can now be put in command class
1512 ** The "maint set python print-stack on|off" is now deleted.
1514 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1515 apply "flag enum"-style pretty-printing to any enum.
1517 ** gdb.lookup_symbol can now work when there is no current frame.
1519 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1520 the source at which the symbol was defined.
1522 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1523 method 'value'. The former indicates whether the symbol needs a
1524 frame in order to compute its value, and the latter computes the
1527 ** A new method 'referenced_value' on gdb.Value objects which can
1528 dereference pointer as well as C++ reference values.
1530 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1531 which return the global and static blocks (as gdb.Block objects),
1532 of the underlying symbol table, respectively.
1534 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1535 object associated with a PC value.
1537 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1538 of the address range occupied by code for the current source line.
1540 * Go language support.
1541 GDB now supports debugging programs written in the Go programming
1544 * GDBserver now supports stdio connections.
1545 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1547 * The binary "gdbtui" can no longer be built or installed.
1548 Use "gdb -tui" instead.
1550 * GDB will now print "flag" enums specially. A flag enum is one where
1551 all the enumerator values have no bits in common when pairwise
1552 "and"ed. When printing a value whose type is a flag enum, GDB will
1553 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1554 (gdb) print (enum E) 3
1557 * The filename part of a linespec will now match trailing components
1558 of a source file name. For example, "break gcc/expr.c:1000" will
1559 now set a breakpoint in build/gcc/expr.c, but not
1560 build/libcpp/expr.c.
1562 * The "info proc" and "generate-core-file" commands will now also
1563 work on remote targets connected to GDBserver on Linux.
1565 * The command "info catch" has been removed. It has been disabled
1566 since December 2007.
1568 * The "catch exception" and "catch assert" commands now accept
1569 a condition at the end of the command, much like the "break"
1570 command does. For instance:
1572 (gdb) catch exception Constraint_Error if Barrier = True
1574 Previously, it was possible to add a condition to such catchpoints,
1575 but it had to be done as a second step, after the catchpoint had been
1576 created, using the "condition" command.
1578 * The "info static-tracepoint-marker" command will now also work on
1579 native Linux targets with in-process agent.
1581 * GDB can now set breakpoints on inlined functions.
1583 * The .gdb_index section has been updated to include symbols for
1584 inlined functions. GDB will ignore older .gdb_index sections by
1585 default, which could cause symbol files to be loaded more slowly
1586 until their .gdb_index sections can be recreated. The new command
1587 "set use-deprecated-index-sections on" will cause GDB to use any older
1588 .gdb_index sections it finds. This will restore performance, but the
1589 ability to set breakpoints on inlined functions will be lost in symbol
1590 files with older .gdb_index sections.
1592 The .gdb_index section has also been updated to record more information
1593 about each symbol. This speeds up the "info variables", "info functions"
1594 and "info types" commands when used with programs having the .gdb_index
1595 section, as well as speeding up debugging with shared libraries using
1596 the .gdb_index section.
1598 * Ada support for GDB/MI Variable Objects has been added.
1600 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1605 ** New command -info-os is the MI equivalent of "info os".
1607 ** Output logs ("set logging" and related) now include MI output.
1611 ** "set use-deprecated-index-sections on|off"
1612 "show use-deprecated-index-sections on|off"
1613 Controls the use of deprecated .gdb_index sections.
1615 ** "catch load" and "catch unload" can be used to stop when a shared
1616 library is loaded or unloaded, respectively.
1618 ** "enable count" can be used to auto-disable a breakpoint after
1621 ** "info vtbl" can be used to show the virtual method tables for
1622 C++ and Java objects.
1624 ** "explore" and its sub commands "explore value" and "explore type"
1625 can be used to recursively explore values and types of
1626 expressions. These commands are available only if GDB is
1627 configured with '--with-python'.
1629 ** "info auto-load" shows status of all kinds of auto-loaded files,
1630 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1631 sequences of commands files, "info auto-load python-scripts"
1632 shows status of auto-loading Python script files,
1633 "info auto-load local-gdbinit" shows status of loading init file
1634 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1635 status of inferior specific thread debugging shared library loading.
1637 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1638 and "show auto-load-scripts" commands have been deprecated, use their
1639 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1640 and "show auto-load python-scripts" counterparts instead.
1642 ** "dprintf location,format,args..." creates a dynamic printf, which
1643 is basically a breakpoint that does a printf and immediately
1644 resumes your program's execution, so it is like a printf that you
1645 can insert dynamically at runtime instead of at compiletime.
1647 ** "set print symbol"
1649 Controls whether GDB attempts to display the symbol, if any,
1650 corresponding to addresses it prints. This defaults to "on", but
1651 you can set it to "off" to restore GDB's previous behavior.
1653 * Deprecated commands
1655 ** For the Renesas Super-H architecture, the "regs" command has been
1656 deprecated, and "info all-registers" should be used instead.
1660 Renesas RL78 rl78-*-elf
1661 HP OpenVMS ia64 ia64-hp-openvms*
1663 * GDBserver supports evaluation of breakpoint conditions. When
1664 support is advertised by GDBserver, GDB may be told to send the
1665 breakpoint conditions in bytecode form to GDBserver. GDBserver
1666 will only report the breakpoint trigger to GDB when its condition
1671 set mips compression
1672 show mips compression
1673 Select the compressed ISA encoding used in functions that have no symbol
1674 information available. The encoding can be set to either of:
1677 and is updated automatically from ELF file flags if available.
1679 set breakpoint condition-evaluation
1680 show breakpoint condition-evaluation
1681 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1682 GDBserver ("target"). Default option "auto" chooses the most efficient
1684 This option can improve debugger efficiency depending on the speed of the
1688 Disable auto-loading globally.
1691 Show auto-loading setting of all kinds of auto-loaded files.
1693 set auto-load gdb-scripts on|off
1694 show auto-load gdb-scripts
1695 Control auto-loading of GDB canned sequences of commands files.
1697 set auto-load python-scripts on|off
1698 show auto-load python-scripts
1699 Control auto-loading of Python script files.
1701 set auto-load local-gdbinit on|off
1702 show auto-load local-gdbinit
1703 Control loading of init file (.gdbinit) from current directory.
1705 set auto-load libthread-db on|off
1706 show auto-load libthread-db
1707 Control auto-loading of inferior specific thread debugging shared library.
1709 set auto-load scripts-directory <dir1>[:<dir2>...]
1710 show auto-load scripts-directory
1711 Set a list of directories from which to load auto-loaded scripts.
1712 Automatically loaded Python scripts and GDB scripts are located in one
1713 of the directories listed by this option.
1714 The delimiter (':' above) may differ according to the host platform.
1716 set auto-load safe-path <dir1>[:<dir2>...]
1717 show auto-load safe-path
1718 Set a list of directories from which it is safe to auto-load files.
1719 The delimiter (':' above) may differ according to the host platform.
1721 set debug auto-load on|off
1722 show debug auto-load
1723 Control display of debugging info for auto-loading the files above.
1725 set dprintf-style gdb|call|agent
1727 Control the way in which a dynamic printf is performed; "gdb"
1728 requests a GDB printf command, while "call" causes dprintf to call a
1729 function in the inferior. "agent" requests that the target agent
1730 (such as GDBserver) do the printing.
1732 set dprintf-function <expr>
1733 show dprintf-function
1734 set dprintf-channel <expr>
1735 show dprintf-channel
1736 Set the function and optional first argument to the call when using
1737 the "call" style of dynamic printf.
1739 set disconnected-dprintf on|off
1740 show disconnected-dprintf
1741 Control whether agent-style dynamic printfs continue to be in effect
1742 after GDB disconnects.
1744 * New configure options
1746 --with-auto-load-dir
1747 Configure default value for the 'set auto-load scripts-directory'
1748 setting above. It defaults to '$debugdir:$datadir/auto-load',
1749 $debugdir representing global debugging info directories (available
1750 via 'show debug-file-directory') and $datadir representing GDB's data
1751 directory (available via 'show data-directory').
1753 --with-auto-load-safe-path
1754 Configure default value for the 'set auto-load safe-path' setting
1755 above. It defaults to the --with-auto-load-dir setting.
1757 --without-auto-load-safe-path
1758 Set 'set auto-load safe-path' to '/', effectively disabling this
1761 * New remote packets
1763 z0/z1 conditional breakpoints extension
1765 The z0/z1 breakpoint insertion packets have been extended to carry
1766 a list of conditional expressions over to the remote stub depending on the
1767 condition evaluation mode. The use of this extension can be controlled
1768 via the "set remote conditional-breakpoints-packet" command.
1772 Specify the signals which the remote stub may pass to the debugged
1773 program without GDB involvement.
1775 * New command line options
1777 --init-command=FILE, -ix Like --command, -x but execute it
1778 before loading inferior.
1779 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1780 execute it before loading inferior.
1782 *** Changes in GDB 7.4
1784 * GDB now handles ambiguous linespecs more consistently; the existing
1785 FILE:LINE support has been expanded to other types of linespecs. A
1786 breakpoint will now be set on all matching locations in all
1787 inferiors, and locations will be added or removed according to
1790 * GDB now allows you to skip uninteresting functions and files when
1791 stepping with the "skip function" and "skip file" commands.
1793 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1794 and "show remote hardware-watchpoint-length-limit". These allows to
1795 set or show the maximum length limit (in bytes) of a remote
1796 target hardware watchpoint.
1798 This allows e.g. to use "unlimited" hardware watchpoints with the
1799 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1800 watchpoints are slower than real hardware watchpoints but are
1801 significantly faster than gdb software watchpoints.
1805 ** The register_pretty_printer function in module gdb.printing now takes
1806 an optional `replace' argument. If True, the new printer replaces any
1809 ** The "maint set python print-stack on|off" command has been
1810 deprecated and will be deleted in GDB 7.5.
1811 A new command: "set python print-stack none|full|message" has
1812 replaced it. Additionally, the default for "print-stack" is
1813 now "message", which just prints the error message without
1816 ** A prompt substitution hook (prompt_hook) is now available to the
1819 ** A new Python module, gdb.prompt has been added to the GDB Python
1820 modules library. This module provides functionality for
1821 escape sequences in prompts (used by set/show
1822 extended-prompt). These escape sequences are replaced by their
1823 corresponding value.
1825 ** Python commands and convenience-functions located in
1826 'data-directory'/python/gdb/command and
1827 'data-directory'/python/gdb/function are now automatically loaded
1830 ** Blocks now provide four new attributes. global_block and
1831 static_block will return the global and static blocks
1832 respectively. is_static and is_global are boolean attributes
1833 that indicate if the block is one of those two types.
1835 ** Symbols now provide the "type" attribute, the type of the symbol.
1837 ** The "gdb.breakpoint" function has been deprecated in favor of
1840 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1841 of a function. This class is based on the "finish" command
1842 available in the CLI.
1844 ** Type objects for struct and union types now allow access to
1845 the fields using standard Python dictionary (mapping) methods.
1846 For example, "some_type['myfield']" now works, as does
1847 "some_type.items()".
1849 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1852 ** A new function, "deep_items" has been added to the gdb.types
1853 module in the GDB Python modules library. This function returns
1854 an iterator over the fields of a struct or union type. Unlike
1855 the standard Python "iteritems" method, it will recursively traverse
1856 any anonymous fields.
1860 ** "*stopped" events can report several new "reason"s, such as
1863 ** Breakpoint changes are now notified using new async records, like
1864 "=breakpoint-modified".
1866 ** New command -ada-task-info.
1868 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1869 $sdir specifies the default system locations of shared libraries.
1870 $pdir specifies the directory where the libpthread used by the application
1873 GDB no longer looks in $sdir and $pdir after it has searched the directories
1874 mentioned in libthread-db-search-path. If you want to search those
1875 directories, they must be specified in libthread-db-search-path.
1876 The default value of libthread-db-search-path on GNU/Linux and Solaris
1877 systems is now "$sdir:$pdir".
1879 $pdir is not supported by gdbserver, it is currently ignored.
1880 $sdir is supported by gdbserver.
1882 * New configure option --with-iconv-bin.
1883 When using the internationalization support like the one in the GNU C
1884 library, GDB will invoke the "iconv" program to get a list of supported
1885 character sets. If this program lives in a non-standard location, one can
1886 use this option to specify where to find it.
1888 * When natively debugging programs on PowerPC BookE processors running
1889 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1890 watchpoints, which specify a mask in addition to an address to watch.
1891 The mask specifies that some bits of an address (the bits which are
1892 reset in the mask) should be ignored when matching the address accessed
1893 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1894 section in the user manual for more details.
1896 * The new option --once causes GDBserver to stop listening for connections once
1897 the first connection is made. The listening port used by GDBserver will
1898 become available after that.
1900 * New commands "info macros" and "alias" have been added.
1902 * New function parameters suffix @entry specifies value of function parameter
1903 at the time the function got called. Entry values are available only since
1909 "!" is now an alias of the "shell" command.
1910 Note that no space is needed between "!" and SHELL COMMAND.
1914 watch EXPRESSION mask MASK_VALUE
1915 The watch command now supports the mask argument which allows creation
1916 of masked watchpoints, if the current architecture supports this feature.
1918 info auto-load-scripts [REGEXP]
1919 This command was formerly named "maintenance print section-scripts".
1920 It is now generally useful and is no longer a maintenance-only command.
1922 info macro [-all] [--] MACRO
1923 The info macro command has new options `-all' and `--'. The first for
1924 printing all definitions of a macro. The second for explicitly specifying
1925 the end of arguments and the beginning of the macro name in case the macro
1926 name starts with a hyphen.
1928 collect[/s] EXPRESSIONS
1929 The tracepoint collect command now takes an optional modifier "/s"
1930 that directs it to dereference pointer-to-character types and
1931 collect the bytes of memory up to a zero byte. The behavior is
1932 similar to what you see when you use the regular print command on a
1933 string. An optional integer following the "/s" sets a bound on the
1934 number of bytes that will be collected.
1937 The trace start command now interprets any supplied arguments as a
1938 note to be recorded with the trace run, with an effect similar to
1939 setting the variable trace-notes.
1942 The trace stop command now interprets any arguments as a note to be
1943 mentioned along with the tstatus report that the trace was stopped
1944 with a command. The effect is similar to setting the variable
1947 * Tracepoints can now be enabled and disabled at any time after a trace
1948 experiment has been started using the standard "enable" and "disable"
1949 commands. It is now possible to start a trace experiment with no enabled
1950 tracepoints; GDB will display a warning, but will allow the experiment to
1951 begin, assuming that tracepoints will be enabled as needed while the trace
1954 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1955 locations with 4-byte instructions, when they were previously
1956 limited to locations with instructions of 5 bytes or longer.
1960 set debug dwarf2-read
1961 show debug dwarf2-read
1962 Turns on or off display of debugging messages related to reading
1963 DWARF debug info. The default is off.
1965 set debug symtab-create
1966 show debug symtab-create
1967 Turns on or off display of debugging messages related to symbol table
1968 creation. The default is off.
1971 show extended-prompt
1972 Set the GDB prompt, and allow escape sequences to be inserted to
1973 display miscellaneous information (see 'help set extended-prompt'
1974 for the list of sequences). This prompt (and any information
1975 accessed through the escape sequences) is updated every time the
1976 prompt is displayed.
1978 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1979 show print entry-values
1980 Set printing of frame argument values at function entry. In some cases
1981 GDB can determine the value of function argument which was passed by the
1982 function caller, even if the value was modified inside the called function.
1984 set debug entry-values
1985 show debug entry-values
1986 Control display of debugging info for determining frame argument values at
1987 function entry and virtual tail call frames.
1989 set basenames-may-differ
1990 show basenames-may-differ
1991 Set whether a source file may have multiple base names.
1992 (A "base name" is the name of a file with the directory part removed.
1993 Example: The base name of "/home/user/hello.c" is "hello.c".)
1994 If set, GDB will canonicalize file names (e.g., expand symlinks)
1995 before comparing them. Canonicalization is an expensive operation,
1996 but it allows the same file be known by more than one base name.
1997 If not set (the default), all source files are assumed to have just
1998 one base name, and gdb will do file name comparisons more efficiently.
2004 Set a user name and notes for the current and any future trace runs.
2005 This is useful for long-running and/or disconnected traces, to
2006 inform others (or yourself) as to who is running the trace, supply
2007 contact information, or otherwise explain what is going on.
2009 set trace-stop-notes
2010 show trace-stop-notes
2011 Set a note attached to the trace run, that is displayed when the
2012 trace has been stopped by a tstop command. This is useful for
2013 instance as an explanation, if you are stopping a trace run that was
2014 started by someone else.
2016 * New remote packets
2020 Dynamically enable a tracepoint in a started trace experiment.
2024 Dynamically disable a tracepoint in a started trace experiment.
2028 Set the user and notes of the trace run.
2032 Query the current status of a tracepoint.
2036 Query the minimum length of instruction at which a fast tracepoint may
2039 * Dcache size (number of lines) and line-size are now runtime-configurable
2040 via "set dcache line" and "set dcache line-size" commands.
2044 Texas Instruments TMS320C6x tic6x-*-*
2048 Renesas RL78 rl78-*-elf
2050 *** Changes in GDB 7.3.1
2052 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2054 *** Changes in GDB 7.3
2056 * GDB has a new command: "thread find [REGEXP]".
2057 It finds the thread id whose name, target id, or thread extra info
2058 matches the given regular expression.
2060 * The "catch syscall" command now works on mips*-linux* targets.
2062 * The -data-disassemble MI command now supports modes 2 and 3 for
2063 dumping the instruction opcodes.
2065 * New command line options
2067 -data-directory DIR Specify DIR as the "data-directory".
2068 This is mostly for testing purposes.
2070 * The "maint set python auto-load on|off" command has been renamed to
2071 "set auto-load-scripts on|off".
2073 * GDB has a new command: "set directories".
2074 It is like the "dir" command except that it replaces the
2075 source path list instead of augmenting it.
2077 * GDB now understands thread names.
2079 On GNU/Linux, "info threads" will display the thread name as set by
2080 prctl or pthread_setname_np.
2082 There is also a new command, "thread name", which can be used to
2083 assign a name internally for GDB to display.
2086 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2087 has been integrated into GDB.
2091 ** The function gdb.Write now accepts an optional keyword 'stream'.
2092 This keyword, when provided, will direct the output to either
2093 stdout, stderr, or GDB's logging output.
2095 ** Parameters can now be be sub-classed in Python, and in particular
2096 you may implement the get_set_doc and get_show_doc functions.
2097 This improves how Parameter set/show documentation is processed
2098 and allows for more dynamic content.
2100 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2101 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2102 have an is_valid method.
2104 ** Breakpoints can now be sub-classed in Python, and in particular
2105 you may implement a 'stop' function that is executed each time
2106 the inferior reaches that breakpoint.
2108 ** New function gdb.lookup_global_symbol looks up a global symbol.
2110 ** GDB values in Python are now callable if the value represents a
2111 function. For example, if 'some_value' represents a function that
2112 takes two integer parameters and returns a value, you can call
2113 that function like so:
2115 result = some_value (10,20)
2117 ** Module gdb.types has been added.
2118 It contains a collection of utilities for working with gdb.Types objects:
2119 get_basic_type, has_field, make_enum_dict.
2121 ** Module gdb.printing has been added.
2122 It contains utilities for writing and registering pretty-printers.
2123 New classes: PrettyPrinter, SubPrettyPrinter,
2124 RegexpCollectionPrettyPrinter.
2125 New function: register_pretty_printer.
2127 ** New commands "info pretty-printers", "enable pretty-printer" and
2128 "disable pretty-printer" have been added.
2130 ** gdb.parameter("directories") is now available.
2132 ** New function gdb.newest_frame returns the newest frame in the
2135 ** The gdb.InferiorThread class has a new "name" attribute. This
2136 holds the thread's name.
2138 ** Python Support for Inferior events.
2139 Python scripts can add observers to be notified of events
2140 occurring in the process being debugged.
2141 The following events are currently supported:
2142 - gdb.events.cont Continue event.
2143 - gdb.events.exited Inferior exited event.
2144 - gdb.events.stop Signal received, and Breakpoint hit events.
2148 ** GDB now puts template parameters in scope when debugging in an
2149 instantiation. For example, if you have:
2151 template<int X> int func (void) { return X; }
2153 then if you step into func<5>, "print X" will show "5". This
2154 feature requires proper debuginfo support from the compiler; it
2155 was added to GCC 4.5.
2157 ** The motion commands "next", "finish", "until", and "advance" now
2158 work better when exceptions are thrown. In particular, GDB will
2159 no longer lose control of the inferior; instead, the GDB will
2160 stop the inferior at the point at which the exception is caught.
2161 This functionality requires a change in the exception handling
2162 code that was introduced in GCC 4.5.
2164 * GDB now follows GCC's rules on accessing volatile objects when
2165 reading or writing target state during expression evaluation.
2166 One notable difference to prior behavior is that "print x = 0"
2167 no longer generates a read of x; the value of the assignment is
2168 now always taken directly from the value being assigned.
2170 * GDB now has some support for using labels in the program's source in
2171 linespecs. For instance, you can use "advance label" to continue
2172 execution to a label.
2174 * GDB now has support for reading and writing a new .gdb_index
2175 section. This section holds a fast index of DWARF debugging
2176 information and can be used to greatly speed up GDB startup and
2177 operation. See the documentation for `save gdb-index' for details.
2179 * The "watch" command now accepts an optional "-location" argument.
2180 When used, this causes GDB to watch the memory referred to by the
2181 expression. Such a watchpoint is never deleted due to it going out
2184 * GDB now supports thread debugging of core dumps on GNU/Linux.
2186 GDB now activates thread debugging using the libthread_db library
2187 when debugging GNU/Linux core dumps, similarly to when debugging
2188 live processes. As a result, when debugging a core dump file, GDB
2189 is now able to display pthread_t ids of threads. For example, "info
2190 threads" shows the same output as when debugging the process when it
2191 was live. In earlier releases, you'd see something like this:
2194 * 1 LWP 6780 main () at main.c:10
2196 While now you see this:
2199 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2201 It is also now possible to inspect TLS variables when debugging core
2204 When debugging a core dump generated on a machine other than the one
2205 used to run GDB, you may need to point GDB at the correct
2206 libthread_db library with the "set libthread-db-search-path"
2207 command. See the user manual for more details on this command.
2209 * When natively debugging programs on PowerPC BookE processors running
2210 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2211 which stop execution of the inferior whenever it executes an instruction
2212 at any address within the specified range. See the "PowerPC Embedded"
2213 section in the user manual for more details.
2215 * New features in the GDB remote stub, GDBserver
2217 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2218 and i686 LynxOS (version 5.x).
2220 ** GDBserver is now supported on Blackfin Linux.
2222 * New native configurations
2224 ia64 HP-UX ia64-*-hpux*
2228 Analog Devices, Inc. Blackfin Processor bfin-*
2230 * Ada task switching is now supported on sparc-elf targets when
2231 debugging a program using the Ravenscar Profile. For more information,
2232 see the "Tasking Support when using the Ravenscar Profile" section
2233 in the GDB user manual.
2235 * Guile support was removed.
2237 * New features in the GNU simulator
2239 ** The --map-info flag lists all known core mappings.
2241 ** CFI flashes may be simulated via the "cfi" device.
2243 *** Changes in GDB 7.2
2245 * Shared library support for remote targets by default
2247 When GDB is configured for a generic, non-OS specific target, like
2248 for example, --target=arm-eabi or one of the many *-*-elf targets,
2249 GDB now queries remote stubs for loaded shared libraries using the
2250 `qXfer:libraries:read' packet. Previously, shared library support
2251 was always disabled for such configurations.
2255 ** Argument Dependent Lookup (ADL)
2257 In C++ ADL lookup directs function search to the namespaces of its
2258 arguments even if the namespace has not been imported.
2268 Here the compiler will search for `foo' in the namespace of 'b'
2269 and find A::foo. GDB now supports this. This construct is commonly
2270 used in the Standard Template Library for operators.
2272 ** Improved User Defined Operator Support
2274 In addition to member operators, GDB now supports lookup of operators
2275 defined in a namespace and imported with a `using' directive, operators
2276 defined in the global scope, operators imported implicitly from an
2277 anonymous namespace, and the ADL operators mentioned in the previous
2279 GDB now also supports proper overload resolution for all the previously
2280 mentioned flavors of operators.
2282 ** static const class members
2284 Printing of static const class members that are initialized in the
2285 class definition has been fixed.
2287 * Windows Thread Information Block access.
2289 On Windows targets, GDB now supports displaying the Windows Thread
2290 Information Block (TIB) structure. This structure is visible either
2291 by using the new command `info w32 thread-information-block' or, by
2292 dereferencing the new convenience variable named `$_tlb', a
2293 thread-specific pointer to the TIB. This feature is also supported
2294 when remote debugging using GDBserver.
2296 * Static tracepoints
2298 Static tracepoints are calls in the user program into a tracing
2299 library. One such library is a port of the LTTng kernel tracer to
2300 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2301 When debugging with GDBserver, GDB now supports combining the GDB
2302 tracepoint machinery with such libraries. For example: the user can
2303 use GDB to probe a static tracepoint marker (a call from the user
2304 program into the tracing library) with the new "strace" command (see
2305 "New commands" below). This creates a "static tracepoint" in the
2306 breakpoint list, that can be manipulated with the same feature set
2307 as fast and regular tracepoints. E.g., collect registers, local and
2308 global variables, collect trace state variables, and define
2309 tracepoint conditions. In addition, the user can collect extra
2310 static tracepoint marker specific data, by collecting the new
2311 $_sdata internal variable. When analyzing the trace buffer, you can
2312 inspect $_sdata like any other variable available to GDB. For more
2313 information, see the "Tracepoints" chapter in GDB user manual. New
2314 remote packets have been defined to support static tracepoints, see
2315 the "New remote packets" section below.
2317 * Better reconstruction of tracepoints after disconnected tracing
2319 GDB will attempt to download the original source form of tracepoint
2320 definitions when starting a trace run, and then will upload these
2321 upon reconnection to the target, resulting in a more accurate
2322 reconstruction of the tracepoints that are in use on the target.
2326 You can now exercise direct control over the ways that GDB can
2327 affect your program. For instance, you can disallow the setting of
2328 breakpoints, so that the program can run continuously (assuming
2329 non-stop mode). In addition, the "observer" variable is available
2330 to switch all of the different controls; in observer mode, GDB
2331 cannot affect the target's behavior at all, which is useful for
2332 tasks like diagnosing live systems in the field.
2334 * The new convenience variable $_thread holds the number of the
2337 * New remote packets
2341 Return the address of the Windows Thread Information Block of a given thread.
2345 In response to several of the tracepoint packets, the target may now
2346 also respond with a number of intermediate `qRelocInsn' request
2347 packets before the final result packet, to have GDB handle
2348 relocating an instruction to execute at a different address. This
2349 is particularly useful for stubs that support fast tracepoints. GDB
2350 reports support for this feature in the qSupported packet.
2354 List static tracepoint markers in the target program.
2358 List static tracepoint markers at a given address in the target
2361 qXfer:statictrace:read
2363 Read the static trace data collected (by a `collect $_sdata'
2364 tracepoint action). The remote stub reports support for this packet
2365 to gdb's qSupported query.
2369 Send the current settings of GDB's permission flags.
2373 Send part of the source (textual) form of a tracepoint definition,
2374 which includes location, conditional, and action list.
2376 * The source command now accepts a -s option to force searching for the
2377 script in the source search path even if the script name specifies
2380 * New features in the GDB remote stub, GDBserver
2382 - GDBserver now support tracepoints (including fast tracepoints, and
2383 static tracepoints). The feature is currently supported by the
2384 i386-linux and amd64-linux builds. See the "Tracepoints support
2385 in gdbserver" section in the manual for more information.
2387 GDBserver JIT compiles the tracepoint's conditional agent
2388 expression bytecode into native code whenever possible for low
2389 overhead dynamic tracepoints conditionals. For such tracepoints,
2390 an expression that examines program state is evaluated when the
2391 tracepoint is reached, in order to determine whether to capture
2392 trace data. If the condition is simple and false, processing the
2393 tracepoint finishes very quickly and no data is gathered.
2395 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2396 for static tracepoints support.
2398 - GDBserver now supports x86_64 Windows 64-bit debugging.
2400 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2401 it understands register description.
2403 * The --batch flag now disables pagination and queries.
2405 * X86 general purpose registers
2407 GDB now supports reading/writing byte, word and double-word x86
2408 general purpose registers directly. This means you can use, say,
2409 $ah or $ax to refer, respectively, to the byte register AH and
2410 16-bit word register AX that are actually portions of the 32-bit
2411 register EAX or 64-bit register RAX.
2413 * The `commands' command now accepts a range of breakpoints to modify.
2414 A plain `commands' following a command that creates multiple
2415 breakpoints affects all the breakpoints set by that command. This
2416 applies to breakpoints set by `rbreak', and also applies when a
2417 single `break' command creates multiple breakpoints (e.g.,
2418 breakpoints on overloaded c++ functions).
2420 * The `rbreak' command now accepts a filename specification as part of
2421 its argument, limiting the functions selected by the regex to those
2422 in the specified file.
2424 * Support for remote debugging Windows and SymbianOS shared libraries
2425 from Unix hosts has been improved. Non Windows GDB builds now can
2426 understand target reported file names that follow MS-DOS based file
2427 system semantics, such as file names that include drive letters and
2428 use the backslash character as directory separator. This makes it
2429 possible to transparently use the "set sysroot" and "set
2430 solib-search-path" on Unix hosts to point as host copies of the
2431 target's shared libraries. See the new command "set
2432 target-file-system-kind" described below, and the "Commands to
2433 specify files" section in the user manual for more information.
2437 eval template, expressions...
2438 Convert the values of one or more expressions under the control
2439 of the string template to a command line, and call it.
2441 set target-file-system-kind unix|dos-based|auto
2442 show target-file-system-kind
2443 Set or show the assumed file system kind for target reported file
2446 save breakpoints <filename>
2447 Save all current breakpoint definitions to a file suitable for use
2448 in a later debugging session. To read the saved breakpoint
2449 definitions, use the `source' command.
2451 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2454 info static-tracepoint-markers
2455 Display information about static tracepoint markers in the target.
2457 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2458 Define a static tracepoint by probing a marker at the given
2459 function, line, address, or marker ID.
2463 Enable and disable observer mode.
2465 set may-write-registers on|off
2466 set may-write-memory on|off
2467 set may-insert-breakpoints on|off
2468 set may-insert-tracepoints on|off
2469 set may-insert-fast-tracepoints on|off
2470 set may-interrupt on|off
2471 Set individual permissions for GDB effects on the target. Note that
2472 some of these settings can have undesirable or surprising
2473 consequences, particularly when changed in the middle of a session.
2474 For instance, disabling the writing of memory can prevent
2475 breakpoints from being inserted, cause single-stepping to fail, or
2476 even crash your program, if you disable after breakpoints have been
2477 inserted. However, GDB should not crash.
2479 set record memory-query on|off
2480 show record memory-query
2481 Control whether to stop the inferior if memory changes caused
2482 by an instruction cannot be recorded.
2487 The disassemble command now supports "start,+length" form of two arguments.
2491 ** GDB now provides a new directory location, called the python directory,
2492 where Python scripts written for GDB can be installed. The location
2493 of that directory is <data-directory>/python, where <data-directory>
2494 is the GDB data directory. For more details, see section `Scripting
2495 GDB using Python' in the manual.
2497 ** The GDB Python API now has access to breakpoints, symbols, symbol
2498 tables, program spaces, inferiors, threads and frame's code blocks.
2499 Additionally, GDB Parameters can now be created from the API, and
2500 manipulated via set/show in the CLI.
2502 ** New functions gdb.target_charset, gdb.target_wide_charset,
2503 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2505 ** New exception gdb.GdbError.
2507 ** Pretty-printers are now also looked up in the current program space.
2509 ** Pretty-printers can now be individually enabled and disabled.
2511 ** GDB now looks for names of Python scripts to auto-load in a
2512 special section named `.debug_gdb_scripts', in addition to looking
2513 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2515 * Tracepoint actions were unified with breakpoint commands. In particular,
2516 there are no longer differences in "info break" output for breakpoints and
2517 tracepoints and the "commands" command can be used for both tracepoints and
2518 regular breakpoints.
2522 ARM Symbian arm*-*-symbianelf*
2524 * D language support.
2525 GDB now supports debugging programs written in the D programming
2528 * GDB now supports the extended ptrace interface for PowerPC which is
2529 available since Linux kernel version 2.6.34. This automatically enables
2530 any hardware breakpoints and additional hardware watchpoints available in
2531 the processor. The old ptrace interface exposes just one hardware
2532 watchpoint and no hardware breakpoints.
2534 * GDB is now able to use the Data Value Compare (DVC) register available on
2535 embedded PowerPC processors to implement in hardware simple watchpoint
2536 conditions of the form:
2538 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2540 This works in native GDB running on Linux kernels with the extended ptrace
2541 interface mentioned above.
2543 *** Changes in GDB 7.1
2547 ** Namespace Support
2549 GDB now supports importing of namespaces in C++. This enables the
2550 user to inspect variables from imported namespaces. Support for
2551 namepace aliasing has also been added. So, if a namespace is
2552 aliased in the current scope (e.g. namepace C=A; ) the user can
2553 print variables using the alias (e.g. (gdb) print C::x).
2557 All known bugs relating to the printing of virtual base class were
2558 fixed. It is now possible to call overloaded static methods using a
2563 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2564 and reinterpret_cast<> are now handled by the C++ expression parser.
2568 Xilinx MicroBlaze microblaze-*-*
2573 Xilinx MicroBlaze microblaze
2576 * Multi-program debugging.
2578 GDB now has support for multi-program (a.k.a. multi-executable or
2579 multi-exec) debugging. This allows for debugging multiple inferiors
2580 simultaneously each running a different program under the same GDB
2581 session. See "Debugging Multiple Inferiors and Programs" in the
2582 manual for more information. This implied some user visible changes
2583 in the multi-inferior support. For example, "info inferiors" now
2584 lists inferiors that are not running yet or that have exited
2585 already. See also "New commands" and "New options" below.
2587 * New tracing features
2589 GDB's tracepoint facility now includes several new features:
2591 ** Trace state variables
2593 GDB tracepoints now include support for trace state variables, which
2594 are variables managed by the target agent during a tracing
2595 experiment. They are useful for tracepoints that trigger each
2596 other, so for instance one tracepoint can count hits in a variable,
2597 and then a second tracepoint has a condition that is true when the
2598 count reaches a particular value. Trace state variables share the
2599 $-syntax of GDB convenience variables, and can appear in both
2600 tracepoint actions and condition expressions. Use the "tvariable"
2601 command to create, and "info tvariables" to view; see "Trace State
2602 Variables" in the manual for more detail.
2606 GDB now includes an option for defining fast tracepoints, which
2607 targets may implement more efficiently, such as by installing a jump
2608 into the target agent rather than a trap instruction. The resulting
2609 speedup can be by two orders of magnitude or more, although the
2610 tradeoff is that some program locations on some target architectures
2611 might not allow fast tracepoint installation, for instance if the
2612 instruction to be replaced is shorter than the jump. To request a
2613 fast tracepoint, use the "ftrace" command, with syntax identical to
2614 the regular trace command.
2616 ** Disconnected tracing
2618 It is now possible to detach GDB from the target while it is running
2619 a trace experiment, then reconnect later to see how the experiment
2620 is going. In addition, a new variable disconnected-tracing lets you
2621 tell the target agent whether to continue running a trace if the
2622 connection is lost unexpectedly.
2626 GDB now has the ability to save the trace buffer into a file, and
2627 then use that file as a target, similarly to you can do with
2628 corefiles. You can select trace frames, print data that was
2629 collected in them, and use tstatus to display the state of the
2630 tracing run at the moment that it was saved. To create a trace
2631 file, use "tsave <filename>", and to use it, do "target tfile
2634 ** Circular trace buffer
2636 You can ask the target agent to handle the trace buffer as a
2637 circular buffer, discarding the oldest trace frames to make room for
2638 newer ones, by setting circular-trace-buffer to on. This feature may
2639 not be available for all target agents.
2644 The disassemble command, when invoked with two arguments, now requires
2645 the arguments to be comma-separated.
2648 The info variables command now displays variable definitions. Files
2649 which only declare a variable are not shown.
2652 The source command is now capable of sourcing Python scripts.
2653 This feature is dependent on the debugger being build with Python
2656 Related to this enhancement is also the introduction of a new command
2657 "set script-extension" (see below).
2659 * New commands (for set/show, see "New options" below)
2661 record save [<FILENAME>]
2662 Save a file (in core file format) containing the process record
2663 execution log for replay debugging at a later time.
2665 record restore <FILENAME>
2666 Restore the process record execution log that was saved at an
2667 earlier time, for replay debugging.
2669 add-inferior [-copies <N>] [-exec <FILENAME>]
2672 clone-inferior [-copies <N>] [ID]
2673 Make a new inferior ready to execute the same program another
2674 inferior has loaded.
2679 maint info program-spaces
2680 List the program spaces loaded into GDB.
2682 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2683 show remote interrupt-sequence
2684 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2685 as the sequence to the remote target in order to interrupt the execution.
2686 Ctrl-C is a default. Some system prefers BREAK which is high level of
2687 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2688 Magic SysRq g. It is BREAK signal and character 'g'.
2690 set remote interrupt-on-connect [on | off]
2691 show remote interrupt-on-connect
2692 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2693 remote target when gdb connects to it. This is needed when you debug
2696 set remotebreak [on | off]
2698 Deprecated. Use "set/show remote interrupt-sequence" instead.
2700 tvariable $NAME [ = EXP ]
2701 Create or modify a trace state variable.
2704 List trace state variables and their values.
2706 delete tvariable $NAME ...
2707 Delete one or more trace state variables.
2710 Evaluate the given expressions without collecting anything into the
2711 trace buffer. (Valid in tracepoint actions only.)
2713 ftrace FN / FILE:LINE / *ADDR
2714 Define a fast tracepoint at the given function, line, or address.
2716 * New expression syntax
2718 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2719 GDB now parses 0b101010 identically with 42.
2723 set follow-exec-mode new|same
2724 show follow-exec-mode
2725 Control whether GDB reuses the same inferior across an exec call or
2726 creates a new one. This is useful to be able to restart the old
2727 executable after the inferior having done an exec call.
2729 set default-collect EXPR, ...
2730 show default-collect
2731 Define a list of expressions to be collected at each tracepoint.
2732 This is a useful way to ensure essential items are not overlooked,
2733 such as registers or a critical global variable.
2735 set disconnected-tracing
2736 show disconnected-tracing
2737 If set to 1, the target is instructed to continue tracing if it
2738 loses its connection to GDB. If 0, the target is to stop tracing
2741 set circular-trace-buffer
2742 show circular-trace-buffer
2743 If set to on, the target is instructed to use a circular trace buffer
2744 and discard the oldest trace frames instead of stopping the trace due
2745 to a full trace buffer. If set to off, the trace stops when the buffer
2746 fills up. Some targets may not support this.
2748 set script-extension off|soft|strict
2749 show script-extension
2750 If set to "off", the debugger does not perform any script language
2751 recognition, and all sourced files are assumed to be GDB scripts.
2752 If set to "soft" (the default), files are sourced according to
2753 filename extension, falling back to GDB scripts if the first
2755 If set to "strict", files are sourced according to filename extension.
2757 set ada trust-PAD-over-XVS on|off
2758 show ada trust-PAD-over-XVS
2759 If off, activate a workaround against a bug in the debugging information
2760 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2761 the GCC sources for more information about the GNAT encoding and
2762 PAD types in particular). It is always safe to set this option to
2763 off, but this introduces a slight performance penalty. The default
2766 * Python API Improvements
2768 ** GDB provides the new class gdb.LazyString. This is useful in
2769 some pretty-printing cases. The new method gdb.Value.lazy_string
2770 provides a simple way to create objects of this type.
2772 ** The fields returned by gdb.Type.fields now have an
2773 `is_base_class' attribute.
2775 ** The new method gdb.Type.range returns the range of an array type.
2777 ** The new method gdb.parse_and_eval can be used to parse and
2778 evaluate an expression.
2780 * New remote packets
2783 Define a trace state variable.
2786 Get the current value of a trace state variable.
2789 Set desired tracing behavior upon disconnection.
2792 Set the trace buffer to be linear or circular.
2795 Get data about the tracepoints currently in use.
2799 Process record now works correctly with hardware watchpoints.
2801 Multiple bug fixes have been made to the mips-irix port, making it
2802 much more reliable. In particular:
2803 - Debugging threaded applications is now possible again. Previously,
2804 GDB would hang while starting the program, or while waiting for
2805 the program to stop at a breakpoint.
2806 - Attaching to a running process no longer hangs.
2807 - An error occurring while loading a core file has been fixed.
2808 - Changing the value of the PC register now works again. This fixes
2809 problems observed when using the "jump" command, or when calling
2810 a function from GDB, or even when assigning a new value to $pc.
2811 - With the "finish" and "return" commands, the return value for functions
2812 returning a small array is now correctly printed.
2813 - It is now possible to break on shared library code which gets executed
2814 during a shared library init phase (code executed while executing
2815 their .init section). Previously, the breakpoint would have no effect.
2816 - GDB is now able to backtrace through the signal handler for
2817 non-threaded programs.
2819 PIE (Position Independent Executable) programs debugging is now supported.
2820 This includes debugging execution of PIC (Position Independent Code) shared
2821 libraries although for that, it should be possible to run such libraries as an
2824 *** Changes in GDB 7.0
2826 * GDB now has an interface for JIT compilation. Applications that
2827 dynamically generate code can create symbol files in memory and register
2828 them with GDB. For users, the feature should work transparently, and
2829 for JIT developers, the interface is documented in the GDB manual in the
2830 "JIT Compilation Interface" chapter.
2832 * Tracepoints may now be conditional. The syntax is as for
2833 breakpoints; either an "if" clause appended to the "trace" command,
2834 or the "condition" command is available. GDB sends the condition to
2835 the target for evaluation using the same bytecode format as is used
2836 for tracepoint actions.
2838 * The disassemble command now supports: an optional /r modifier, print the
2839 raw instructions in hex as well as in symbolic form, and an optional /m
2840 modifier to print mixed source+assembly.
2842 * Process record and replay
2844 In a architecture environment that supports ``process record and
2845 replay'', ``process record and replay'' target can record a log of
2846 the process execution, and replay it with both forward and reverse
2849 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2850 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2851 set execution-direction {forward|reverse}, for targets that support
2854 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2855 feature is available with a native GDB running on kernel version
2858 * GDB now has support for multi-byte and wide character sets on the
2859 target. Strings whose character type is wchar_t, char16_t, or
2860 char32_t are now correctly printed. GDB supports wide- and unicode-
2861 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2862 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2863 `printf'. This feature requires iconv to work properly; if your
2864 system does not have a working iconv, GDB can use GNU libiconv. See
2865 the installation instructions for more information.
2867 * GDB now supports automatic retrieval of shared library files from
2868 remote targets. To use this feature, specify a system root that begins
2869 with the `remote:' prefix, either via the `set sysroot' command or via
2870 the `--with-sysroot' configure-time option.
2872 * "info sharedlibrary" now takes an optional regex of libraries to show,
2873 and it now reports if a shared library has no debugging information.
2875 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2876 now complete on file names.
2878 * When completing in expressions, gdb will attempt to limit
2879 completions to allowable structure or union fields, where appropriate.
2880 For instance, consider:
2882 # struct example { int f1; double f2; };
2883 # struct example variable;
2886 If the user types TAB at the end of this command line, the available
2887 completions will be "f1" and "f2".
2889 * Inlined functions are now supported. They show up in backtraces, and
2890 the "step", "next", and "finish" commands handle them automatically.
2892 * GDB now supports the token-splicing (##) and stringification (#)
2893 operators when expanding macros. It also supports variable-arity
2896 * GDB now supports inspecting extra signal information, exported by
2897 the new $_siginfo convenience variable. The feature is currently
2898 implemented on linux ARM, i386 and amd64.
2900 * GDB can now display the VFP floating point registers and NEON vector
2901 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2902 can provide these registers (requires Linux 2.6.30 or later). Remote
2903 and simulator targets may also provide them.
2905 * New remote packets
2908 Search memory for a sequence of bytes.
2911 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2912 operation over reliable transport links. Use of this packet is
2913 controlled by the `set remote noack-packet' command.
2916 Kill the process with the specified process ID. Use this in preference
2917 to `k' when multiprocess protocol extensions are supported.
2920 Obtains additional operating system information
2924 Read or write additional signal information.
2926 * Removed remote protocol undocumented extension
2928 An undocumented extension to the remote protocol's `S' stop reply
2929 packet that permited the stub to pass a process id was removed.
2930 Remote servers should use the `T' stop reply packet instead.
2932 * GDB now supports multiple function calling conventions according to the
2933 DWARF-2 DW_AT_calling_convention function attribute.
2935 * The SH target utilizes the aforementioned change to distinguish between gcc
2936 and Renesas calling convention. It also adds the new CLI commands
2937 `set/show sh calling-convention'.
2939 * GDB can now read compressed debug sections, as produced by GNU gold
2940 with the --compress-debug-sections=zlib flag.
2942 * 64-bit core files are now supported on AIX.
2944 * Thread switching is now supported on Tru64.
2946 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2947 which will be allocated using malloc later in program execution.
2949 * The qXfer:libraries:read remote procotol packet now allows passing a
2950 list of section offsets.
2952 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2953 conditions handling signals delivered during attach or thread creation
2954 have also been fixed.
2956 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2957 From the user's standpoint, all unqualified instances of True and False
2958 are treated as the standard definitions, regardless of context.
2960 * GDB now parses C++ symbol and type names more flexibly. For
2963 template<typename T> class C { };
2966 GDB will now correctly handle all of:
2968 ptype C<char const *>
2969 ptype C<char const*>
2970 ptype C<const char *>
2971 ptype C<const char*>
2973 * New features in the GDB remote stub, gdbserver
2975 - The "--wrapper" command-line argument tells gdbserver to use a
2976 wrapper program to launch programs for debugging.
2978 - On PowerPC and S/390 targets, it is now possible to use a single
2979 gdbserver executable to debug both 32-bit and 64-bit programs.
2980 (This requires gdbserver itself to be built as a 64-bit executable.)
2982 - gdbserver uses the new noack protocol mode for TCP connections to
2983 reduce communications latency, if also supported and enabled in GDB.
2985 - Support for the sparc64-linux-gnu target is now included in
2988 - The amd64-linux build of gdbserver now supports debugging both
2989 32-bit and 64-bit programs.
2991 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2992 now support hardware watchpoints, and will use them automatically
2997 GDB now has support for scripting using Python. Whether this is
2998 available is determined at configure time.
3000 New GDB commands can now be written in Python.
3002 * Ada tasking support
3004 Ada tasks can now be inspected in GDB. The following commands have
3008 Print the list of Ada tasks.
3010 Print detailed information about task number N.
3012 Print the task number of the current task.
3014 Switch the context of debugging to task number N.
3016 * Support for user-defined prefixed commands. The "define" command can
3017 add new commands to existing prefixes, e.g. "target".
3019 * Multi-inferior, multi-process debugging.
3021 GDB now has generalized support for multi-inferior debugging. See
3022 "Debugging Multiple Inferiors" in the manual for more information.
3023 Although availability still depends on target support, the command
3024 set is more uniform now. The GNU/Linux specific multi-forks support
3025 has been migrated to this new framework. This implied some user
3026 visible changes; see "New commands" and also "Removed commands"
3029 * Target descriptions can now describe the target OS ABI. See the
3030 "Target Description Format" section in the user manual for more
3033 * Target descriptions can now describe "compatible" architectures
3034 to indicate that the target can execute applications for a different
3035 architecture in addition to those for the main target architecture.
3036 See the "Target Description Format" section in the user manual for
3039 * Multi-architecture debugging.
3041 GDB now includes general supports for debugging applications on
3042 hybrid systems that use more than one single processor architecture
3043 at the same time. Each such hybrid architecture still requires
3044 specific support to be added. The only hybrid architecture supported
3045 in this version of GDB is the Cell Broadband Engine.
3047 * GDB now supports integrated debugging of Cell/B.E. applications that
3048 use both the PPU and SPU architectures. To enable support for hybrid
3049 Cell/B.E. debugging, you need to configure GDB to support both the
3050 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3051 --enable-targets configure option.
3053 * Non-stop mode debugging.
3055 For some targets, GDB now supports an optional mode of operation in
3056 which you can examine stopped threads while other threads continue
3057 to execute freely. This is referred to as non-stop mode, with the
3058 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3059 section in the user manual for more information.
3061 To be able to support remote non-stop debugging, a remote stub needs
3062 to implement the non-stop mode remote protocol extensions, as
3063 described in the "Remote Non-Stop" section of the user manual. The
3064 GDB remote stub, gdbserver, has been adjusted to support these
3065 extensions on linux targets.
3067 * New commands (for set/show, see "New options" below)
3069 catch syscall [NAME(S) | NUMBER(S)]
3070 Catch system calls. Arguments, which should be names of system
3071 calls or their numbers, mean catch only those syscalls. Without
3072 arguments, every syscall will be caught. When the inferior issues
3073 any of the specified syscalls, GDB will stop and announce the system
3074 call, both when it is called and when its call returns. This
3075 feature is currently available with a native GDB running on the
3076 Linux Kernel, under the following architectures: x86, x86_64,
3077 PowerPC and PowerPC64.
3079 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3081 Search memory for a sequence of bytes.
3083 maint set python print-stack
3084 maint show python print-stack
3085 Show a stack trace when an error is encountered in a Python script.
3088 Invoke CODE by passing it to the Python interpreter.
3093 These allow macros to be defined, undefined, and listed
3097 Show operating system information about processes.
3100 List the inferiors currently under GDB's control.
3103 Switch focus to inferior number NUM.
3106 Detach from inferior number NUM.
3109 Kill inferior number NUM.
3113 set spu stop-on-load
3114 show spu stop-on-load
3115 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3117 set spu auto-flush-cache
3118 show spu auto-flush-cache
3119 Control whether to automatically flush the software-managed cache
3120 during Cell/B.E. debugging.
3122 set sh calling-convention
3123 show sh calling-convention
3124 Control the calling convention used when calling SH target functions.
3127 show debug timestamp
3128 Control display of timestamps with GDB debugging output.
3130 set disassemble-next-line
3131 show disassemble-next-line
3132 Control display of disassembled source lines or instructions when
3135 set remote noack-packet
3136 show remote noack-packet
3137 Set/show the use of remote protocol QStartNoAckMode packet. See above
3138 under "New remote packets."
3140 set remote query-attached-packet
3141 show remote query-attached-packet
3142 Control use of remote protocol `qAttached' (query-attached) packet.
3144 set remote read-siginfo-object
3145 show remote read-siginfo-object
3146 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3149 set remote write-siginfo-object
3150 show remote write-siginfo-object
3151 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3154 set remote reverse-continue
3155 show remote reverse-continue
3156 Control use of remote protocol 'bc' (reverse-continue) packet.
3158 set remote reverse-step
3159 show remote reverse-step
3160 Control use of remote protocol 'bs' (reverse-step) packet.
3162 set displaced-stepping
3163 show displaced-stepping
3164 Control displaced stepping mode. Displaced stepping is a way to
3165 single-step over breakpoints without removing them from the debuggee.
3166 Also known as "out-of-line single-stepping".
3169 show debug displaced
3170 Control display of debugging info for displaced stepping.
3172 maint set internal-error
3173 maint show internal-error
3174 Control what GDB does when an internal error is detected.
3176 maint set internal-warning
3177 maint show internal-warning
3178 Control what GDB does when an internal warning is detected.
3183 Use a wrapper program to launch programs for debugging.
3185 set multiple-symbols (all|ask|cancel)
3186 show multiple-symbols
3187 The value of this variable can be changed to adjust the debugger behavior
3188 when an expression or a breakpoint location contains an ambiguous symbol
3189 name (an overloaded function name, for instance).
3191 set breakpoint always-inserted
3192 show breakpoint always-inserted
3193 Keep breakpoints always inserted in the target, as opposed to inserting
3194 them when resuming the target, and removing them when the target stops.
3195 This option can improve debugger performance on slow remote targets.
3197 set arm fallback-mode (arm|thumb|auto)
3198 show arm fallback-mode
3199 set arm force-mode (arm|thumb|auto)
3201 These commands control how ARM GDB determines whether instructions
3202 are ARM or Thumb. The default for both settings is auto, which uses
3203 the current CPSR value for instructions without symbols; previous
3204 versions of GDB behaved as if "set arm fallback-mode arm".
3206 set disable-randomization
3207 show disable-randomization
3208 Standalone programs run with the virtual address space randomization enabled
3209 by default on some platforms. This option keeps the addresses stable across
3210 multiple debugging sessions.
3214 Control whether other threads are stopped or not when some thread hits
3219 Requests that asynchronous execution is enabled in the target, if available.
3220 In this case, it's possible to resume target in the background, and interact
3221 with GDB while the target is running. "show target-async" displays the
3222 current state of asynchronous execution of the target.
3224 set target-wide-charset
3225 show target-wide-charset
3226 The target-wide-charset is the name of the character set that GDB
3227 uses when printing characters whose type is wchar_t.
3229 set tcp auto-retry (on|off)
3231 set tcp connect-timeout
3232 show tcp connect-timeout
3233 These commands allow GDB to retry failed TCP connections to a remote stub
3234 with a specified timeout period; this is useful if the stub is launched
3235 in parallel with GDB but may not be ready to accept connections immediately.
3237 set libthread-db-search-path
3238 show libthread-db-search-path
3239 Control list of directories which GDB will search for appropriate
3242 set schedule-multiple (on|off)
3243 show schedule-multiple
3244 Allow GDB to resume all threads of all processes or only threads of
3245 the current process.
3249 Use more aggressive caching for accesses to the stack. This improves
3250 performance of remote debugging (particularly backtraces) without
3251 affecting correctness.
3253 set interactive-mode (on|off|auto)
3254 show interactive-mode
3255 Control whether GDB runs in interactive mode (on) or not (off).
3256 When in interactive mode, GDB waits for the user to answer all
3257 queries. Otherwise, GDB does not wait and assumes the default
3258 answer. When set to auto (the default), GDB determines which
3259 mode to use based on the stdin settings.
3264 For program forks, this is replaced by the new more generic `info
3265 inferiors' command. To list checkpoints, you can still use the
3266 `info checkpoints' command, which was an alias for the `info forks'
3270 Replaced by the new `inferior' command. To switch between
3271 checkpoints, you can still use the `restart' command, which was an
3272 alias for the `fork' command.
3275 This is removed, since some targets don't have a notion of
3276 processes. To switch between processes, you can still use the
3277 `inferior' command using GDB's own inferior number.
3280 For program forks, this is replaced by the new more generic `kill
3281 inferior' command. To delete a checkpoint, you can still use the
3282 `delete checkpoint' command, which was an alias for the `delete
3286 For program forks, this is replaced by the new more generic `detach
3287 inferior' command. To detach a checkpoint, you can still use the
3288 `detach checkpoint' command, which was an alias for the `detach
3291 * New native configurations
3293 x86/x86_64 Darwin i[34567]86-*-darwin*
3295 x86_64 MinGW x86_64-*-mingw*
3299 Lattice Mico32 lm32-*
3300 x86 DICOS i[34567]86-*-dicos*
3301 x86_64 DICOS x86_64-*-dicos*
3304 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3305 (mingw32ce) debugging.
3311 These commands were actually not implemented on any target.
3313 *** Changes in GDB 6.8
3315 * New native configurations
3317 NetBSD/hppa hppa*-*netbsd*
3318 Xtensa GNU/Linux xtensa*-*-linux*
3322 NetBSD/hppa hppa*-*-netbsd*
3323 Xtensa GNU/Lunux xtensa*-*-linux*
3325 * Change in command line behavior -- corefiles vs. process ids.
3327 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3328 attaching to process NUMBER fails, GDB no longer attempts to open a
3329 core file named NUMBER. Attaching to a program using the -c option
3330 is no longer supported. Instead, use the '-p' or '--pid' options.
3332 * GDB can now be built as a native debugger for debugging Windows x86
3333 (mingw32) Portable Executable (PE) programs.
3335 * Pending breakpoints no longer change their number when their address
3338 * GDB now supports breakpoints with multiple locations,
3339 including breakpoints on C++ constructors, inside C++ templates,
3340 and in inlined functions.
3342 * GDB's ability to debug optimized code has been improved. GDB more
3343 accurately identifies function bodies and lexical blocks that occupy
3344 more than one contiguous range of addresses.
3346 * Target descriptions can now describe registers for PowerPC.
3348 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3349 registers on PowerPC targets.
3351 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3352 targets even when the libthread_db library is not available.
3354 * The GDB remote stub, gdbserver, now supports the new file transfer
3355 commands (remote put, remote get, and remote delete).
3357 * The GDB remote stub, gdbserver, now supports run and attach in
3358 extended-remote mode.
3360 * hppa*64*-*-hpux11* target broken
3361 The debugger is unable to start a program and fails with the following
3362 error: "Error trying to get information about dynamic linker".
3363 The gdb-6.7 release is also affected.
3365 * GDB now supports the --enable-targets= configure option to allow
3366 building a single GDB executable that supports multiple remote
3367 target architectures.
3369 * GDB now supports debugging C and C++ programs which use the
3370 Decimal Floating Point extension. In addition, the PowerPC target
3371 now has a set of pseudo-registers to inspect decimal float values
3372 stored in two consecutive float registers.
3374 * The -break-insert MI command can optionally create pending
3377 * Improved support for debugging Ada
3378 Many improvements to the Ada language support have been made. These
3380 - Better support for Ada2005 interface types
3381 - Improved handling of arrays and slices in general
3382 - Better support for Taft-amendment types
3383 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3385 - Improved command completion in Ada
3388 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3393 set print frame-arguments (all|scalars|none)
3394 show print frame-arguments
3395 The value of this variable can be changed to control which argument
3396 values should be printed by the debugger when displaying a frame.
3401 Transfer files to and from a remote target, and delete remote files.
3408 Transfer files to and from a remote target, and delete remote files.
3410 * New remote packets
3417 Open, close, read, write, and delete files on the remote system.
3420 Attach to an existing process on the remote system, in extended-remote
3424 Run a new process on the remote system, in extended-remote mode.
3426 *** Changes in GDB 6.7
3428 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3429 bfd, libiberty and opcodes, as revealed by static analysis donated by
3430 Coverity, Inc. (http://scan.coverity.com).
3432 * When looking up multiply-defined global symbols, GDB will now prefer the
3433 symbol definition in the current shared library if it was built using the
3434 -Bsymbolic linker option.
3436 * When the Text User Interface (TUI) is not configured, GDB will now
3437 recognize the -tui command-line option and print a message that the TUI
3440 * The GDB remote stub, gdbserver, now has lower overhead for high
3441 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3443 * GDB for MIPS targets now autodetects whether a remote target provides
3444 32-bit or 64-bit register values.
3446 * Support for C++ member pointers has been improved.
3448 * GDB now understands XML target descriptions, which specify the
3449 target's overall architecture. GDB can read a description from
3450 a local file or over the remote serial protocol.
3452 * Vectors of single-byte data use a new integer type which is not
3453 automatically displayed as character or string data.
3455 * The /s format now works with the print command. It displays
3456 arrays of single-byte integers and pointers to single-byte integers
3459 * Target descriptions can now describe target-specific registers,
3460 for architectures which have implemented the support (currently
3461 only ARM, M68K, and MIPS).
3463 * GDB and the GDB remote stub, gdbserver, now support the XScale
3466 * The GDB remote stub, gdbserver, has been updated to support
3467 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3468 has been rewritten to use the standard GDB remote protocol.
3470 * GDB can now step into C++ functions which are called through thunks.
3472 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3474 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3475 layout. It also supports a TextSeg= and DataSeg= response when only
3476 segment base addresses (rather than offsets) are available.
3478 * The /i format now outputs any trailing branch delay slot instructions
3479 immediately following the last instruction within the count specified.
3481 * The GDB remote protocol "T" stop reply packet now supports a
3482 "library" response. Combined with the new "qXfer:libraries:read"
3483 packet, this response allows GDB to debug shared libraries on targets
3484 where the operating system manages the list of loaded libraries (e.g.
3485 Windows and SymbianOS).
3487 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3488 (DLLs) on Windows and Windows CE targets.
3490 * GDB now supports a faster verification that a .debug file matches its binary
3491 according to its build-id signature, if the signature is present.
3497 Enable or disable hardware flow control (RTS/CTS) on the serial port
3498 when debugging using remote targets.
3500 set mem inaccessible-by-default
3501 show mem inaccessible-by-default
3502 If the target supplies a memory map, for instance via the remote
3503 protocol's "qXfer:memory-map:read" packet, setting this variable
3504 prevents GDB from accessing memory outside the memory map. This
3505 is useful for targets with memory mapped registers or which react
3506 badly to accesses of unmapped address space.
3508 set breakpoint auto-hw
3509 show breakpoint auto-hw
3510 If the target supplies a memory map, for instance via the remote
3511 protocol's "qXfer:memory-map:read" packet, setting this variable
3512 lets GDB use hardware breakpoints automatically for memory regions
3513 where it can not use software breakpoints. This covers both the
3514 "break" command and internal breakpoints used for other commands
3515 including "next" and "finish".
3518 catch exception unhandled
3519 Stop the program execution when Ada exceptions are raised.
3522 Stop the program execution when an Ada assertion failed.
3526 Set an alternate system root for target files. This is a more
3527 general version of "set solib-absolute-prefix", which is now
3528 an alias to "set sysroot".
3531 Provide extended SPU facility status information. This set of
3532 commands is available only when debugging the Cell/B.E. SPU
3535 * New native configurations
3537 OpenBSD/sh sh*-*openbsd*
3540 unset tdesc filename
3542 Use the specified local file as an XML target description, and do
3543 not query the target for its built-in description.
3547 OpenBSD/sh sh*-*-openbsd*
3548 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3549 Toshiba Media Processor mep-elf
3551 * New remote packets
3554 Ignore the specified signals; pass them directly to the debugged program
3555 without stopping other threads or reporting them to GDB.
3557 qXfer:features:read:
3558 Read an XML target description from the target, which describes its
3563 Read or write contents of an spufs file on the target system. These
3564 packets are available only on the Cell/B.E. SPU architecture.
3566 qXfer:libraries:read:
3567 Report the loaded shared libraries. Combined with new "T" packet
3568 response, this packet allows GDB to debug shared libraries on
3569 targets where the operating system manages the list of loaded
3570 libraries (e.g. Windows and SymbianOS).
3574 Support for these obsolete configurations has been removed.
3582 i[34567]86-*-lynxos*
3583 i[34567]86-*-netware*
3584 i[34567]86-*-sco3.2v5*
3585 i[34567]86-*-sco3.2v4*
3587 i[34567]86-*-sysv4.2*
3590 i[34567]86-*-unixware2*
3591 i[34567]86-*-unixware*
3600 * Other removed features
3607 Various m68k-only ROM monitors.
3614 Various Renesas ROM monitors and debugging interfaces for SH and
3619 Support for a Macraigor serial interface to on-chip debugging.
3620 GDB does not directly support the newer parallel or USB
3625 A debug information format. The predecessor to DWARF 2 and
3626 DWARF 3, which are still supported.
3628 Support for the HP aCC compiler on HP-UX/PA-RISC
3630 SOM-encapsulated symbolic debugging information, automatic
3631 invocation of pxdb, and the aCC custom C++ ABI. This does not
3632 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3633 with aCC can still be debugged on an assembly level.
3635 MIPS ".pdr" sections
3637 A MIPS-specific format used to describe stack frame layout
3638 in debugging information.
3642 GDB could work with an older version of Guile to debug
3643 the interpreter and Scheme programs running in it.
3645 set mips stack-arg-size
3646 set mips saved-gpreg-size
3648 Use "set mips abi" to control parameter passing for MIPS.
3650 *** Changes in GDB 6.6
3655 Cell Broadband Engine SPU spu-elf
3657 * GDB can now be configured as a cross-debugger targeting native Windows
3658 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3659 running on a Windows system over TCP/IP to debug Windows programs.
3661 * The GDB remote stub, gdbserver, has been updated to support Windows and
3662 Cygwin debugging. Both single-threaded and multi-threaded programs are
3665 * The "set trust-readonly-sections" command works again. This command was
3666 broken in GDB 6.3, 6.4, and 6.5.
3668 * The "load" command now supports writing to flash memory, if the remote
3669 stub provides the required support.
3671 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3672 longer requires symbolic debug information (e.g. DWARF-2).
3677 unset substitute-path
3678 show substitute-path
3679 Manage a list of substitution rules that GDB uses to rewrite the name
3680 of the directories where the sources are located. This can be useful
3681 for instance when the sources were moved to a different location
3682 between compilation and debugging.
3686 Print each CLI command as it is executed. Each command is prefixed with
3687 a number of `+' symbols representing the nesting depth.
3688 The source command now has a `-v' option to enable the same feature.
3692 The ARM Demon monitor support (RDP protocol, "target rdp").
3694 Kernel Object Display, an embedded debugging feature which only worked with
3695 an obsolete version of Cisco IOS.
3697 The 'set download-write-size' and 'show download-write-size' commands.
3699 * New remote packets
3702 Tell a stub about GDB client features, and request remote target features.
3703 The first feature implemented is PacketSize, which allows the target to
3704 specify the size of packets it can handle - to minimize the number of
3705 packets required and improve performance when connected to a remote
3709 Fetch an OS auxilliary vector from the remote stub. This packet is a
3710 more efficient replacement for qPart:auxv:read.
3712 qXfer:memory-map:read:
3713 Fetch a memory map from the remote stub, including information about
3714 RAM, ROM, and flash memory devices.
3719 Erase and program a flash memory device.
3721 * Removed remote packets
3724 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3725 used it, and only gdbserver implemented it.
3727 *** Changes in GDB 6.5
3731 Renesas M32C/M16C m32c-elf
3733 Morpho Technologies ms1 ms1-elf
3737 init-if-undefined Initialize a convenience variable, but
3738 only if it doesn't already have a value.
3740 The following commands are presently only implemented for native GNU/Linux:
3742 checkpoint Save a snapshot of the program state.
3744 restart <n> Return the program state to a
3745 previously saved state.
3747 info checkpoints List currently saved checkpoints.
3749 delete-checkpoint <n> Delete a previously saved checkpoint.
3751 set|show detach-on-fork Tell gdb whether to detach from a newly
3752 forked process, or to keep debugging it.
3754 info forks List forks of the user program that
3755 are available to be debugged.
3757 fork <n> Switch to debugging one of several
3758 forks of the user program that are
3759 available to be debugged.
3761 delete-fork <n> Delete a fork from the list of forks
3762 that are available to be debugged (and
3763 kill the forked process).
3765 detach-fork <n> Delete a fork from the list of forks
3766 that are available to be debugged (and
3767 allow the process to continue).
3771 Morpho Technologies ms2 ms1-elf
3773 * Improved Windows host support
3775 GDB now builds as a cross debugger hosted on i686-mingw32, including
3776 native console support, and remote communications using either
3777 network sockets or serial ports.
3779 * Improved Modula-2 language support
3781 GDB can now print most types in the Modula-2 syntax. This includes:
3782 basic types, set types, record types, enumerated types, range types,
3783 pointer types and ARRAY types. Procedure var parameters are correctly
3784 printed and hexadecimal addresses and character constants are also
3785 written in the Modula-2 syntax. Best results can be obtained by using
3786 GNU Modula-2 together with the -gdwarf-2 command line option.
3790 The ARM rdi-share module.
3792 The Netware NLM debug server.
3794 *** Changes in GDB 6.4
3796 * New native configurations
3798 OpenBSD/arm arm*-*-openbsd*
3799 OpenBSD/mips64 mips64-*-openbsd*
3803 Morpho Technologies ms1 ms1-elf
3805 * New command line options
3807 --batch-silent As for --batch, but totally silent.
3808 --return-child-result The debugger will exist with the same value
3809 the child (debugged) program exited with.
3810 --eval-command COMMAND, -ex COMMAND
3811 Execute a single GDB CLI command. This may be
3812 specified multiple times and in conjunction
3813 with the --command (-x) option.
3815 * Deprecated commands removed
3817 The following commands, that were deprecated in 2000, have been
3821 set|show arm disassembly-flavor set|show arm disassembler
3822 othernames set arm disassembler
3823 set|show remotedebug set|show debug remote
3824 set|show archdebug set|show debug arch
3825 set|show eventdebug set|show debug event
3828 * New BSD user-level threads support
3830 It is now possible to debug programs using the user-level threads
3831 library on OpenBSD and FreeBSD. Currently supported (target)
3834 FreeBSD/amd64 x86_64-*-freebsd*
3835 FreeBSD/i386 i386-*-freebsd*
3836 OpenBSD/i386 i386-*-openbsd*
3838 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3839 are not yet supported.
3841 * New support for Matsushita MN10300 w/sim added
3842 (Work in progress). mn10300-elf.
3844 * REMOVED configurations and files
3846 VxWorks and the XDR protocol *-*-vxworks
3847 Motorola MCORE mcore-*-*
3848 National Semiconductor NS32000 ns32k-*-*
3850 * New "set print array-indexes" command
3852 After turning this setting "on", GDB prints the index of each element
3853 when displaying arrays. The default is "off" to preserve the previous
3856 * VAX floating point support
3858 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3860 * User-defined command support
3862 In addition to using $arg0..$arg9 for argument passing, it is now possible
3863 to use $argc to determine now many arguments have been passed. See the
3864 section on user-defined commands in the user manual for more information.
3866 *** Changes in GDB 6.3:
3868 * New command line option
3870 GDB now accepts -l followed by a number to set the timeout for remote
3873 * GDB works with GCC -feliminate-dwarf2-dups
3875 GDB now supports a more compact representation of DWARF-2 debug
3876 information using DW_FORM_ref_addr references. These are produced
3877 by GCC with the option -feliminate-dwarf2-dups and also by some
3878 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3879 to use -feliminate-dwarf2-dups.
3881 * Internationalization
3883 When supported by the host system, GDB will be built with
3884 internationalization (libintl). The task of marking up the sources is
3885 continued, we're looking forward to our first translation.
3889 Initial support for debugging programs compiled with the GNAT
3890 implementation of the Ada programming language has been integrated
3891 into GDB. In this release, support is limited to expression evaluation.
3893 * New native configurations
3895 GNU/Linux/m32r m32r-*-linux-gnu
3899 GDB's remote protocol now includes support for the 'p' packet. This
3900 packet is used to fetch individual registers from a remote inferior.
3902 * END-OF-LIFE registers[] compatibility module
3904 GDB's internal register infrastructure has been completely rewritten.
3905 The new infrastructure making possible the implementation of key new
3906 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3909 GDB 6.3 will be the last release to include the the registers[]
3910 compatibility module that allowed out-of-date configurations to
3911 continue to work. This change directly impacts the following
3921 powerpc bdm protocol
3923 Unless there is activity to revive these configurations, they will be
3924 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3926 * OBSOLETE configurations and files
3928 Configurations that have been declared obsolete in this release have
3929 been commented out. Unless there is activity to revive these
3930 configurations, the next release of GDB will have their sources
3931 permanently REMOVED.
3940 *** Changes in GDB 6.2.1:
3942 * MIPS `break main; run' gave an heuristic-fence-post warning
3944 When attempting to run even a simple program, a warning about
3945 heuristic-fence-post being hit would be reported. This problem has
3948 * MIPS IRIX 'long double' crashed GDB
3950 When examining a long double variable, GDB would get a segmentation
3951 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3952 IRIX long double values).
3956 A bug in the VAX stack code was causing problems with the "next"
3957 command. This problem has been fixed.
3959 *** Changes in GDB 6.2:
3961 * Fix for ``many threads''
3963 On GNU/Linux systems that use the NPTL threads library, a program
3964 rapidly creating and deleting threads would confuse GDB leading to the
3967 ptrace: No such process.
3968 thread_db_get_info: cannot get thread info: generic error
3970 This problem has been fixed.
3972 * "-async" and "-noasync" options removed.
3974 Support for the broken "-noasync" option has been removed (it caused
3977 * New ``start'' command.
3979 This command runs the program until the begining of the main procedure.
3981 * New BSD Kernel Data Access Library (libkvm) interface
3983 Using ``target kvm'' it is now possible to debug kernel core dumps and
3984 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3985 platforms. Currently supported (native-only) configurations are:
3987 FreeBSD/amd64 x86_64-*-freebsd*
3988 FreeBSD/i386 i?86-*-freebsd*
3989 NetBSD/i386 i?86-*-netbsd*
3990 NetBSD/m68k m68*-*-netbsd*
3991 NetBSD/sparc sparc-*-netbsd*
3992 OpenBSD/amd64 x86_64-*-openbsd*
3993 OpenBSD/i386 i?86-*-openbsd*
3994 OpenBSD/m68k m68*-openbsd*
3995 OpenBSD/sparc sparc-*-openbsd*
3997 * Signal trampoline code overhauled
3999 Many generic problems with GDB's signal handling code have been fixed.
4000 These include: backtraces through non-contiguous stacks; recognition
4001 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4002 call; backtrace through a signal trampoline; step into and out of
4003 signal handlers; and single-stepping in the signal trampoline.
4005 Please note that kernel bugs are a limiting factor here. These
4006 features have been shown to work on an s390 GNU/Linux system that
4007 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4009 * Cygwin support for DWARF 2 added.
4011 * New native configurations
4013 GNU/Linux/hppa hppa*-*-linux*
4014 OpenBSD/hppa hppa*-*-openbsd*
4015 OpenBSD/m68k m68*-*-openbsd*
4016 OpenBSD/m88k m88*-*-openbsd*
4017 OpenBSD/powerpc powerpc-*-openbsd*
4018 NetBSD/vax vax-*-netbsd*
4019 OpenBSD/vax vax-*-openbsd*
4021 * END-OF-LIFE frame compatibility module
4023 GDB's internal frame infrastructure has been completely rewritten.
4024 The new infrastructure making it possible to support key new features
4025 including DWARF 2 Call Frame Information. To aid in the task of
4026 migrating old configurations to this new infrastructure, a
4027 compatibility module, that allowed old configurations to continue to
4028 work, was also included.
4030 GDB 6.2 will be the last release to include this frame compatibility
4031 module. This change directly impacts the following configurations:
4041 Unless there is activity to revive these configurations, they will be
4042 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4044 * REMOVED configurations and files
4046 Sun 3, running SunOS 3 m68*-*-sunos3*
4047 Sun 3, running SunOS 4 m68*-*-sunos4*
4048 Sun 2, running SunOS 3 m68000-*-sunos3*
4049 Sun 2, running SunOS 4 m68000-*-sunos4*
4050 Motorola 680x0 running LynxOS m68*-*-lynxos*
4051 AT&T 3b1/Unix pc m68*-att-*
4052 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4053 decstation mips-dec-* mips-little-*
4054 riscos mips-*-riscos* mips-*-sysv*
4055 sonymips mips-sony-*
4056 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4058 *** Changes in GDB 6.1.1:
4060 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4062 The TUI (Text-mode User Interface) is now built as part of a default
4063 GDB configuration. It is enabled by either selecting the TUI with the
4064 command line option "-i=tui" or by running the separate "gdbtui"
4065 program. For more information on the TUI, see the manual "Debugging
4068 * Pending breakpoint support (also included in GDB 6.1)
4070 Support has been added to allow you to specify breakpoints in shared
4071 libraries that have not yet been loaded. If a breakpoint location
4072 cannot be found, and the "breakpoint pending" option is set to auto,
4073 GDB queries you if you wish to make the breakpoint pending on a future
4074 shared-library load. If and when GDB resolves the breakpoint symbol,
4075 the pending breakpoint is removed as one or more regular breakpoints
4078 Pending breakpoints are very useful for GCJ Java debugging.
4080 * Fixed ISO-C build problems
4082 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4083 non ISO-C code that stopped them being built using a more strict ISO-C
4084 compiler (e.g., IBM's C compiler).
4086 * Fixed build problem on IRIX 5
4088 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4089 wasn't able to compile compile on an IRIX 5 system.
4091 * Added execute permission to gdb/gdbserver/configure
4093 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4094 permission. This bug would cause configure to fail on a number of
4095 systems (Solaris, IRIX). Ref: server/519.
4097 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4099 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4100 has been updated to use constant array sizes.
4102 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4104 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4105 its generated DWARF Call Frame Info. This encoding was causing GDB to
4106 panic, that panic has been fixed. Ref: gdb/1628.
4108 * Fixed a problem when examining parameters in shared library code.
4110 When examining parameters in optimized shared library code generated
4111 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4112 not available''. GDB now correctly displays the variable's value.
4114 *** Changes in GDB 6.1:
4116 * Removed --with-mmalloc
4118 Support for the mmalloc memory manager has been removed, as it
4119 conflicted with the internal gdb byte cache.
4121 * Changes in AMD64 configurations
4123 The AMD64 target now includes the %cs and %ss registers. As a result
4124 the AMD64 remote protocol has changed; this affects the floating-point
4125 and SSE registers. If you rely on those registers for your debugging,
4126 you should upgrade gdbserver on the remote side.
4128 * Revised SPARC target
4130 The SPARC target has been completely revised, incorporating the
4131 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4132 support for LynxOS and SunOS 4 has been dropped. Calling functions
4133 from within GDB on operating systems with a non-executable stack
4134 (Solaris, OpenBSD) now works.
4138 GDB has a new C++ demangler which does a better job on the mangled
4139 names generated by current versions of g++. It also runs faster, so
4140 with this and other changes gdb should now start faster on large C++
4143 * DWARF 2 Location Expressions
4145 GDB support for location expressions has been extended to support function
4146 arguments and frame bases. Older versions of GDB could crash when they
4149 * C++ nested types and namespaces
4151 GDB's support for nested types and namespaces in C++ has been
4152 improved, especially if you use the DWARF 2 debugging format. (This
4153 is the default for recent versions of GCC on most platforms.)
4154 Specifically, if you have a class "Inner" defined within a class or
4155 namespace "Outer", then GDB realizes that the class's name is
4156 "Outer::Inner", not simply "Inner". This should greatly reduce the
4157 frequency of complaints about not finding RTTI symbols. In addition,
4158 if you are stopped at inside of a function defined within a namespace,
4159 GDB modifies its name lookup accordingly.
4161 * New native configurations
4163 NetBSD/amd64 x86_64-*-netbsd*
4164 OpenBSD/amd64 x86_64-*-openbsd*
4165 OpenBSD/alpha alpha*-*-openbsd*
4166 OpenBSD/sparc sparc-*-openbsd*
4167 OpenBSD/sparc64 sparc64-*-openbsd*
4169 * New debugging protocols
4171 M32R with SDI protocol m32r-*-elf*
4173 * "set prompt-escape-char" command deleted.
4175 The command "set prompt-escape-char" has been deleted. This command,
4176 and its very obscure effet on GDB's prompt, was never documented,
4177 tested, nor mentioned in the NEWS file.
4179 * OBSOLETE configurations and files
4181 Configurations that have been declared obsolete in this release have
4182 been commented out. Unless there is activity to revive these
4183 configurations, the next release of GDB will have their sources
4184 permanently REMOVED.
4186 Sun 3, running SunOS 3 m68*-*-sunos3*
4187 Sun 3, running SunOS 4 m68*-*-sunos4*
4188 Sun 2, running SunOS 3 m68000-*-sunos3*
4189 Sun 2, running SunOS 4 m68000-*-sunos4*
4190 Motorola 680x0 running LynxOS m68*-*-lynxos*
4191 AT&T 3b1/Unix pc m68*-att-*
4192 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4193 decstation mips-dec-* mips-little-*
4194 riscos mips-*-riscos* mips-*-sysv*
4195 sonymips mips-sony-*
4196 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4198 * REMOVED configurations and files
4200 SGI Irix-4.x mips-sgi-irix4 or iris4
4201 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4202 Z8000 simulator z8k-zilog-none or z8ksim
4203 Matsushita MN10200 w/simulator mn10200-*-*
4204 H8/500 simulator h8500-hitachi-hms or h8500hms
4205 HP/PA running BSD hppa*-*-bsd*
4206 HP/PA running OSF/1 hppa*-*-osf*
4207 HP/PA Pro target hppa*-*-pro*
4208 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4209 386BSD i[3456]86-*-bsd*
4210 Sequent family i[3456]86-sequent-sysv4*
4211 i[3456]86-sequent-sysv*
4212 i[3456]86-sequent-bsd*
4213 SPARC running LynxOS sparc-*-lynxos*
4214 SPARC running SunOS 4 sparc-*-sunos4*
4215 Tsqware Sparclet sparclet-*-*
4216 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4218 *** Changes in GDB 6.0:
4222 Support for debugging the Objective-C programming language has been
4223 integrated into GDB.
4225 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4227 DWARF 2's Call Frame Information makes available compiler generated
4228 information that more exactly describes the program's run-time stack.
4229 By using this information, GDB is able to provide more robust stack
4232 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4233 have been updated to use a new backtrace mechanism which includes
4234 DWARF 2 CFI support.
4238 GDB's remote protocol has been extended to include support for hosted
4239 file I/O (where the remote target uses GDB's file system). See GDB's
4240 remote protocol documentation for details.
4242 * All targets using the new architecture framework.
4244 All of GDB's targets have been updated to use the new internal
4245 architecture framework. The way is now open for future GDB releases
4246 to include cross-architecture native debugging support (i386 on amd64,
4249 * GNU/Linux's Thread Local Storage (TLS)
4251 GDB now includes support for for the GNU/Linux implementation of
4252 per-thread variables.
4254 * GNU/Linux's Native POSIX Thread Library (NPTL)
4256 GDB's thread code has been updated to work with either the new
4257 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4259 * Separate debug info.
4261 GDB, in conjunction with BINUTILS, now supports a mechanism for
4262 automatically loading debug information from a separate file. Instead
4263 of shipping full debug and non-debug versions of system libraries,
4264 system integrators can now instead ship just the stripped libraries
4265 and optional debug files.
4267 * DWARF 2 Location Expressions
4269 DWARF 2 Location Expressions allow the compiler to more completely
4270 describe the location of variables (even in optimized code) to the
4273 GDB now includes preliminary support for location expressions (support
4274 for DW_OP_piece is still missing).
4278 A number of long standing bugs that caused GDB to die while starting a
4279 Java application have been fixed. GDB's Java support is now
4280 considered "useable".
4282 * GNU/Linux support for fork, vfork, and exec.
4284 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4285 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4288 * GDB supports logging output to a file
4290 There are two new commands, "set logging" and "show logging", which can be
4291 used to capture GDB's output to a file.
4293 * The meaning of "detach" has changed for gdbserver
4295 The "detach" command will now resume the application, as documented. To
4296 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4299 * d10v, m68hc11 `regs' command deprecated
4301 The `info registers' command has been updated so that it displays the
4302 registers using a format identical to the old `regs' command.
4306 A new command, "maint set profile on/off", has been added. This command can
4307 be used to enable or disable profiling while running GDB, to profile a
4308 session or a set of commands. In addition there is a new configure switch,
4309 "--enable-profiling", which will cause GDB to be compiled with profiling
4310 data, for more informative profiling results.
4312 * Default MI syntax changed to "mi2".
4314 The default MI (machine interface) syntax, enabled by the command line
4315 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4316 "mi1", can be enabled by specifying the option "-i=mi1".
4318 Support for the original "mi0" syntax (included in GDB 5.0) has been
4321 Fix for gdb/192: removed extraneous space when displaying frame level.
4322 Fix for gdb/672: update changelist is now output in mi list format.
4323 Fix for gdb/702: a -var-assign that updates the value now shows up
4324 in a subsequent -var-update.
4326 * New native configurations.
4328 FreeBSD/amd64 x86_64-*-freebsd*
4330 * Multi-arched targets.
4332 HP/PA HPUX11 hppa*-*-hpux*
4333 Renesas M32R/D w/simulator m32r-*-elf*
4335 * OBSOLETE configurations and files
4337 Configurations that have been declared obsolete in this release have
4338 been commented out. Unless there is activity to revive these
4339 configurations, the next release of GDB will have their sources
4340 permanently REMOVED.
4342 Z8000 simulator z8k-zilog-none or z8ksim
4343 Matsushita MN10200 w/simulator mn10200-*-*
4344 H8/500 simulator h8500-hitachi-hms or h8500hms
4345 HP/PA running BSD hppa*-*-bsd*
4346 HP/PA running OSF/1 hppa*-*-osf*
4347 HP/PA Pro target hppa*-*-pro*
4348 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4349 Sequent family i[3456]86-sequent-sysv4*
4350 i[3456]86-sequent-sysv*
4351 i[3456]86-sequent-bsd*
4352 Tsqware Sparclet sparclet-*-*
4353 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4355 * REMOVED configurations and files
4358 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4359 IBM AIX PS/2 i[3456]86-*-aix
4360 i386 running Mach 3.0 i[3456]86-*-mach3*
4361 i386 running Mach i[3456]86-*-mach*
4362 i386 running OSF/1 i[3456]86-*osf1mk*
4363 HP/Apollo 68k Family m68*-apollo*-sysv*,
4365 m68*-hp-bsd*, m68*-hp-hpux*
4366 Argonaut Risc Chip (ARC) arc-*-*
4367 Mitsubishi D30V d30v-*-*
4368 Fujitsu FR30 fr30-*-elf*
4369 OS/9000 i[34]86-*-os9k
4370 I960 with MON960 i960-*-coff
4372 * MIPS $fp behavior changed
4374 The convenience variable $fp, for the MIPS, now consistently returns
4375 the address of the current frame's base. Previously, depending on the
4376 context, $fp could refer to either $sp or the current frame's base
4377 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4378 The GNU Source-Level Debugger''.
4380 *** Changes in GDB 5.3:
4382 * GNU/Linux shared library multi-threaded performance improved.
4384 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4385 `/proc', in preference to `ptrace' for memory reads. This may result
4386 in an improvement in the start-up time of multi-threaded, shared
4387 library applications when run under GDB. One GDB user writes: ``loads
4388 shared libs like mad''.
4390 * ``gdbserver'' now supports multi-threaded applications on some targets
4392 Support for debugging multi-threaded applications which use
4393 the GNU/Linux LinuxThreads package has been added for
4394 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4395 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4397 * GDB now supports C/C++ preprocessor macros.
4399 GDB now expands preprocessor macro invocations in C/C++ expressions,
4400 and provides various commands for showing macro definitions and how
4403 The new command `macro expand EXPRESSION' expands any macro
4404 invocations in expression, and shows the result.
4406 The new command `show macro MACRO-NAME' shows the definition of the
4407 macro named MACRO-NAME, and where it was defined.
4409 Most compilers don't include information about macros in the debugging
4410 information by default. In GCC 3.1, for example, you need to compile
4411 your program with the options `-gdwarf-2 -g3'. If the macro
4412 information is present in the executable, GDB will read it.
4414 * Multi-arched targets.
4416 DEC Alpha (partial) alpha*-*-*
4417 DEC VAX (partial) vax-*-*
4419 National Semiconductor NS32000 (partial) ns32k-*-*
4420 Motorola 68000 (partial) m68k-*-*
4421 Motorola MCORE mcore-*-*
4425 Fujitsu FRV architecture added by Red Hat frv*-*-*
4428 * New native configurations
4430 Alpha NetBSD alpha*-*-netbsd*
4431 SH NetBSD sh*-*-netbsdelf*
4432 MIPS NetBSD mips*-*-netbsd*
4433 UltraSPARC NetBSD sparc64-*-netbsd*
4435 * OBSOLETE configurations and files
4437 Configurations that have been declared obsolete in this release have
4438 been commented out. Unless there is activity to revive these
4439 configurations, the next release of GDB will have their sources
4440 permanently REMOVED.
4442 Mitsubishi D30V d30v-*-*
4443 OS/9000 i[34]86-*-os9k
4444 IBM AIX PS/2 i[3456]86-*-aix
4445 Fujitsu FR30 fr30-*-elf*
4446 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4447 Argonaut Risc Chip (ARC) arc-*-*
4448 i386 running Mach 3.0 i[3456]86-*-mach3*
4449 i386 running Mach i[3456]86-*-mach*
4450 i386 running OSF/1 i[3456]86-*osf1mk*
4451 HP/Apollo 68k Family m68*-apollo*-sysv*,
4453 m68*-hp-bsd*, m68*-hp-hpux*
4454 I960 with MON960 i960-*-coff
4456 * OBSOLETE languages
4458 CHILL, a Pascal like language used by telecommunications companies.
4460 * REMOVED configurations and files
4462 AMD 29k family via UDI a29k-amd-udi, udi29k
4463 A29K VxWorks a29k-*-vxworks
4464 AMD 29000 embedded, using EBMON a29k-none-none
4465 AMD 29000 embedded with COFF a29k-none-coff
4466 AMD 29000 embedded with a.out a29k-none-aout
4468 testsuite/gdb.hp/gdb.threads-hp/ directory
4470 * New command "set max-user-call-depth <nnn>"
4472 This command allows the user to limit the call depth of user-defined
4473 commands. The default is 1024.
4475 * Changes in FreeBSD/i386 native debugging.
4477 Support for the "generate-core-file" has been added.
4479 * New commands "dump", "append", and "restore".
4481 These commands allow data to be copied from target memory
4482 to a bfd-format or binary file (dump and append), and back
4483 from a file into memory (restore).
4485 * Improved "next/step" support on multi-processor Alpha Tru64.
4487 The previous single-step mechanism could cause unpredictable problems,
4488 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4489 of a software single-step mechanism prevents this.
4491 *** Changes in GDB 5.2.1:
4499 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4500 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4501 Fix, by Joel Brobecker imported from mainline.
4503 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4504 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4505 Fix, by Fred Fish, imported from mainline.
4507 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4508 Surprisingly enough, it works now.
4509 By Michal Ludvig, imported from mainline.
4511 i386 hardware watchpoint support:
4512 avoid misses on second run for some targets.
4513 By Pierre Muller, imported from mainline.
4515 *** Changes in GDB 5.2:
4517 * New command "set trust-readonly-sections on[off]".
4519 This command is a hint that tells gdb that read-only sections
4520 really are read-only (ie. that their contents will not change).
4521 In this mode, gdb will go to the object file rather than the
4522 target to read memory from read-only sections (such as ".text").
4523 This can be a significant performance improvement on some
4524 (notably embedded) targets.
4526 * New command "generate-core-file" (or "gcore").
4528 This new gdb command allows the user to drop a core file of the child
4529 process state at any time. So far it's been implemented only for
4530 GNU/Linux and Solaris, but should be relatively easily ported to other
4531 hosts. Argument is core file name (defaults to core.<pid>).
4533 * New command line option
4535 GDB now accepts --pid or -p followed by a process id.
4537 * Change in command line behavior -- corefiles vs. process ids.
4539 There is a subtle behavior in the way in which GDB handles
4540 command line arguments. The first non-flag argument is always
4541 a program to debug, but the second non-flag argument may either
4542 be a corefile or a process id. Previously, GDB would attempt to
4543 open the second argument as a corefile, and if that failed, would
4544 issue a superfluous error message and then attempt to attach it as
4545 a process. Now, if the second argument begins with a non-digit,
4546 it will be treated as a corefile. If it begins with a digit,
4547 GDB will attempt to attach it as a process, and if no such process
4548 is found, will then attempt to open it as a corefile.
4550 * Changes in ARM configurations.
4552 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4553 configuration is fully multi-arch.
4555 * New native configurations
4557 ARM NetBSD arm*-*-netbsd*
4558 x86 OpenBSD i[3456]86-*-openbsd*
4559 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4560 Sparc64 running FreeBSD sparc64-*-freebsd*
4564 Sanyo XStormy16 xstormy16-elf
4566 * OBSOLETE configurations and files
4568 Configurations that have been declared obsolete in this release have
4569 been commented out. Unless there is activity to revive these
4570 configurations, the next release of GDB will have their sources
4571 permanently REMOVED.
4573 AMD 29k family via UDI a29k-amd-udi, udi29k
4574 A29K VxWorks a29k-*-vxworks
4575 AMD 29000 embedded, using EBMON a29k-none-none
4576 AMD 29000 embedded with COFF a29k-none-coff
4577 AMD 29000 embedded with a.out a29k-none-aout
4579 testsuite/gdb.hp/gdb.threads-hp/ directory
4581 * REMOVED configurations and files
4583 TI TMS320C80 tic80-*-*
4585 PowerPC Solaris powerpcle-*-solaris*
4586 PowerPC Windows NT powerpcle-*-cygwin32
4587 PowerPC Netware powerpc-*-netware*
4588 Harris/CXUX m88k m88*-harris-cxux*
4589 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4590 ns32k-utek-sysv* ns32k-utek-*
4591 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4592 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4593 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4594 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4595 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4597 * Changes to command line processing
4599 The new `--args' feature can be used to specify command-line arguments
4600 for the inferior from gdb's command line.
4602 * Changes to key bindings
4604 There is a new `operate-and-get-next' function bound to `C-o'.
4606 *** Changes in GDB 5.1.1
4608 Fix compile problem on DJGPP.
4610 Fix a problem with floating-point registers on the i386 being
4613 Fix to stop GDB crashing on .debug_str debug info.
4615 Numerous documentation fixes.
4617 Numerous testsuite fixes.
4619 *** Changes in GDB 5.1:
4621 * New native configurations
4623 Alpha FreeBSD alpha*-*-freebsd*
4624 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4625 MIPS GNU/Linux mips*-*-linux*
4626 MIPS SGI Irix 6.x mips*-sgi-irix6*
4627 ia64 AIX ia64-*-aix*
4628 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4632 Motorola 68HC11 and 68HC12 m68hc11-elf
4634 UltraSparc running GNU/Linux sparc64-*-linux*
4636 * OBSOLETE configurations and files
4638 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4639 Harris/CXUX m88k m88*-harris-cxux*
4640 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4641 ns32k-utek-sysv* ns32k-utek-*
4642 TI TMS320C80 tic80-*-*
4644 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4645 PowerPC Solaris powerpcle-*-solaris*
4646 PowerPC Windows NT powerpcle-*-cygwin32
4647 PowerPC Netware powerpc-*-netware*
4648 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4649 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4650 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4651 Apple Macintosh (MPW) host N/A
4653 stuff.c (Program to stuff files into a specially prepared space in kdb)
4654 kdb-start.c (Main loop for the standalone kernel debugger)
4656 Configurations that have been declared obsolete in this release have
4657 been commented out. Unless there is activity to revive these
4658 configurations, the next release of GDB will have their sources
4659 permanently REMOVED.
4661 * REMOVED configurations and files
4663 Altos 3068 m68*-altos-*
4664 Convex c1-*-*, c2-*-*
4666 ARM RISCix arm-*-* (as host)
4670 * GDB has been converted to ISO C.
4672 GDB's source code has been converted to ISO C. In particular, the
4673 sources are fully protoized, and rely on standard headers being
4678 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4680 * The MI enabled by default.
4682 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4683 revised and enabled by default. Packages which use GDB as a debugging
4684 engine behind a UI or another front end are encouraged to switch to
4685 using the GDB/MI interface, instead of the old annotations interface
4686 which is now deprecated.
4688 * Support for debugging Pascal programs.
4690 GDB now includes support for debugging Pascal programs. The following
4691 main features are supported:
4693 - Pascal-specific data types such as sets;
4695 - automatic recognition of Pascal sources based on file-name
4698 - Pascal-style display of data types, variables, and functions;
4700 - a Pascal expression parser.
4702 However, some important features are not yet supported.
4704 - Pascal string operations are not supported at all;
4706 - there are some problems with boolean types;
4708 - Pascal type hexadecimal constants are not supported
4709 because they conflict with the internal variables format;
4711 - support for Pascal objects and classes is not full yet;
4713 - unlike Pascal, GDB is case-sensitive for symbol names.
4715 * Changes in completion.
4717 Commands such as `shell', `run' and `set args', which pass arguments
4718 to inferior programs, now complete on file names, similar to what
4719 users expect at the shell prompt.
4721 Commands which accept locations, such as `disassemble', `print',
4722 `breakpoint', `until', etc. now complete on filenames as well as
4723 program symbols. Thus, if you type "break foob TAB", and the source
4724 files linked into the programs include `foobar.c', that file name will
4725 be one of the candidates for completion. However, file names are not
4726 considered for completion after you typed a colon that delimits a file
4727 name from a name of a function in that file, as in "break foo.c:bar".
4729 `set demangle-style' completes on available demangling styles.
4731 * New platform-independent commands:
4733 It is now possible to define a post-hook for a command as well as a
4734 hook that runs before the command. For more details, see the
4735 documentation of `hookpost' in the GDB manual.
4737 * Changes in GNU/Linux native debugging.
4739 Support for debugging multi-threaded programs has been completely
4740 revised for all platforms except m68k and sparc. You can now debug as
4741 many threads as your system allows you to have.
4743 Attach/detach is supported for multi-threaded programs.
4745 Support for SSE registers was added for x86. This doesn't work for
4746 multi-threaded programs though.
4748 * Changes in MIPS configurations.
4750 Multi-arch support is enabled for all MIPS configurations.
4752 GDB can now be built as native debugger on SGI Irix 6.x systems for
4753 debugging n32 executables. (Debugging 64-bit executables is not yet
4756 * Unified support for hardware watchpoints in all x86 configurations.
4758 Most (if not all) native x86 configurations support hardware-assisted
4759 breakpoints and watchpoints in a unified manner. This support
4760 implements debug register sharing between watchpoints, which allows to
4761 put a virtually infinite number of watchpoints on the same address,
4762 and also supports watching regions up to 16 bytes with several debug
4765 The new maintenance command `maintenance show-debug-regs' toggles
4766 debugging print-outs in functions that insert, remove, and test
4767 watchpoints and hardware breakpoints.
4769 * Changes in the DJGPP native configuration.
4771 New command ``info dos sysinfo'' displays assorted information about
4772 the CPU, OS, memory, and DPMI server.
4774 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4775 display information about segment descriptors stored in GDT, LDT, and
4778 New commands ``info dos pde'' and ``info dos pte'' display entries
4779 from Page Directory and Page Tables (for now works with CWSDPMI only).
4780 New command ``info dos address-pte'' displays the Page Table entry for
4781 a given linear address.
4783 GDB can now pass command lines longer than 126 characters to the
4784 program being debugged (requires an update to the libdbg.a library
4785 which is part of the DJGPP development kit).
4787 DWARF2 debug info is now supported.
4789 It is now possible to `step' and `next' through calls to `longjmp'.
4791 * Changes in documentation.
4793 All GDB documentation was converted to GFDL, the GNU Free
4794 Documentation License.
4796 Tracepoints-related commands are now fully documented in the GDB
4799 TUI, the Text-mode User Interface, is now documented in the manual.
4801 Tracepoints-related commands are now fully documented in the GDB
4804 The "GDB Internals" manual now has an index. It also includes
4805 documentation of `ui_out' functions, GDB coding standards, x86
4806 hardware watchpoints, and memory region attributes.
4808 * GDB's version number moved to ``version.in''
4810 The Makefile variable VERSION has been replaced by the file
4811 ``version.in''. People creating GDB distributions should update the
4812 contents of this file.
4816 GUD support is now a standard part of the EMACS distribution.
4818 *** Changes in GDB 5.0:
4820 * Improved support for debugging FP programs on x86 targets
4822 Unified and much-improved support for debugging floating-point
4823 programs on all x86 targets. In particular, ``info float'' now
4824 displays the FP registers in the same format on all x86 targets, with
4825 greater level of detail.
4827 * Improvements and bugfixes in hardware-assisted watchpoints
4829 It is now possible to watch array elements, struct members, and
4830 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4831 on x86 targets no longer erroneously trigger when the address is
4834 * Improvements in the native DJGPP version of GDB
4836 The distribution now includes all the scripts and auxiliary files
4837 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4838 machines ``out of the box''.
4840 The DJGPP version can now debug programs that use signals. It is
4841 possible to catch signals that happened in the debuggee, deliver
4842 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4843 would kill the program being debugged.) Programs that hook hardware
4844 interrupts (keyboard, timer, etc.) can also be debugged.
4846 It is now possible to debug DJGPP programs that redirect their
4847 standard handles or switch them to raw (as opposed to cooked) mode, or
4848 even close them. The command ``run < foo > bar'' works as expected,
4849 and ``info terminal'' reports useful information about the debuggee's
4850 terminal, including raw/cooked mode, redirection, etc.
4852 The DJGPP version now uses termios functions for console I/O, which
4853 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4856 DOS-style file names with drive letters are now fully supported by
4859 It is now possible to debug DJGPP programs that switch their working
4860 directory. It is also possible to rerun the debuggee any number of
4861 times without restarting GDB; thus, you can use the same setup,
4862 breakpoints, etc. for many debugging sessions.
4864 * New native configurations
4866 ARM GNU/Linux arm*-*-linux*
4867 PowerPC GNU/Linux powerpc-*-linux*
4871 Motorola MCore mcore-*-*
4872 x86 VxWorks i[3456]86-*-vxworks*
4873 PowerPC VxWorks powerpc-*-vxworks*
4874 TI TMS320C80 tic80-*-*
4876 * OBSOLETE configurations
4878 Altos 3068 m68*-altos-*
4879 Convex c1-*-*, c2-*-*
4881 ARM RISCix arm-*-* (as host)
4884 Configurations that have been declared obsolete will be commented out,
4885 but the code will be left in place. If there is no activity to revive
4886 these configurations before the next release of GDB, the sources will
4887 be permanently REMOVED.
4889 * Gould support removed
4891 Support for the Gould PowerNode and NP1 has been removed.
4893 * New features for SVR4
4895 On SVR4 native platforms (such as Solaris), if you attach to a process
4896 without first loading a symbol file, GDB will now attempt to locate and
4897 load symbols from the running process's executable file.
4899 * Many C++ enhancements
4901 C++ support has been greatly improved. Overload resolution now works properly
4902 in almost all cases. RTTI support is on the way.
4904 * Remote targets can connect to a sub-program
4906 A popen(3) style serial-device has been added. This device starts a
4907 sub-process (such as a stand-alone simulator) and then communicates
4908 with that. The sub-program to run is specified using the syntax
4909 ``|<program> <args>'' vis:
4911 (gdb) set remotedebug 1
4912 (gdb) target extended-remote |mn10300-elf-sim program-args
4914 * MIPS 64 remote protocol
4916 A long standing bug in the mips64 remote protocol where by GDB
4917 expected certain 32 bit registers (ex SR) to be transfered as 32
4918 instead of 64 bits has been fixed.
4920 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4921 added to provide backward compatibility with older versions of GDB.
4923 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4925 The command ``set remotebinarydownload'' command has been replaced by
4926 ``set remote X-packet''. Other commands in ``set remote'' family
4927 include ``set remote P-packet''.
4929 * Breakpoint commands accept ranges.
4931 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4932 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4933 ``tracepoint passcount'' also accepts a range of tracepoints.
4935 * ``apropos'' command added.
4937 The ``apropos'' command searches through command names and
4938 documentation strings, printing out matches, making it much easier to
4939 try to find a command that does what you are looking for.
4943 A new machine oriented interface (MI) has been added to GDB. This
4944 interface is designed for debug environments running GDB as a separate
4945 process. This is part of the long term libGDB project. See the
4946 "GDB/MI" chapter of the GDB manual for further information. It can be
4947 enabled by configuring with:
4949 .../configure --enable-gdbmi
4951 *** Changes in GDB-4.18:
4953 * New native configurations
4955 HP-UX 10.20 hppa*-*-hpux10.20
4956 HP-UX 11.x hppa*-*-hpux11.0*
4957 M68K GNU/Linux m68*-*-linux*
4961 Fujitsu FR30 fr30-*-elf*
4962 Intel StrongARM strongarm-*-*
4963 Mitsubishi D30V d30v-*-*
4965 * OBSOLETE configurations
4967 Gould PowerNode, NP1 np1-*-*, pn-*-*
4969 Configurations that have been declared obsolete will be commented out,
4970 but the code will be left in place. If there is no activity to revive
4971 these configurations before the next release of GDB, the sources will
4972 be permanently REMOVED.
4976 As a compatibility experiment, GDB's source files buildsym.h and
4977 buildsym.c have been converted to pure standard C, no longer
4978 containing any K&R compatibility code. We believe that all systems in
4979 use today either come with a standard C compiler, or have a GCC port
4980 available. If this is not true, please report the affected
4981 configuration to bug-gdb@gnu.org immediately. See the README file for
4982 information about getting a standard C compiler if you don't have one
4987 GDB now uses readline 2.2.
4989 * set extension-language
4991 You can now control the mapping between filename extensions and source
4992 languages by using the `set extension-language' command. For instance,
4993 you can ask GDB to treat .c files as C++ by saying
4994 set extension-language .c c++
4995 The command `info extensions' lists all of the recognized extensions
4996 and their associated languages.
4998 * Setting processor type for PowerPC and RS/6000
5000 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5001 you can use the `set processor' command to specify what variant of the
5002 PowerPC family you are debugging. The command
5006 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5007 following PowerPC and RS6000 variants:
5009 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5010 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5012 403GC IBM PowerPC 403GC
5013 505 Motorola PowerPC 505
5014 860 Motorola PowerPC 860 or 850
5015 601 Motorola PowerPC 601
5016 602 Motorola PowerPC 602
5017 603 Motorola/IBM PowerPC 603 or 603e
5018 604 Motorola PowerPC 604 or 604e
5019 750 Motorola/IBM PowerPC 750 or 750
5021 At the moment, this command just tells GDB what to name the
5022 special-purpose processor registers. Since almost all the affected
5023 registers are inaccessible to user-level programs, this command is
5024 only useful for remote debugging in its present form.
5028 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5029 more extensive support for HP-UX. Added features include shared
5030 library support, kernel threads and hardware watchpoints for 11.00,
5031 support for HP's ANSI C and C++ compilers, and a compatibility mode
5032 for xdb and dbx commands.
5036 HP's donation includes the new concept of catchpoints, which is a
5037 generalization of the old catch command. On HP-UX, it is now possible
5038 to catch exec, fork, and vfork, as well as library loading.
5040 This means that the existing catch command has changed; its first
5041 argument now specifies the type of catch to be set up. See the
5042 output of "help catch" for a list of catchpoint types.
5044 * Debugging across forks
5046 On HP-UX, you can choose which process to debug when a fork() happens
5051 HP has donated a curses-based terminal user interface (TUI). To get
5052 it, build with --enable-tui. Although this can be enabled for any
5053 configuration, at present it only works for native HP debugging.
5055 * GDB remote protocol additions
5057 A new protocol packet 'X' that writes binary data is now available.
5058 Default behavior is to try 'X', then drop back to 'M' if the stub
5059 fails to respond. The settable variable `remotebinarydownload'
5060 allows explicit control over the use of 'X'.
5062 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5063 full 64-bit address. The command
5065 set remoteaddresssize 32
5067 can be used to revert to the old behaviour. For existing remote stubs
5068 the change should not be noticed, as the additional address information
5071 In order to assist in debugging stubs, you may use the maintenance
5072 command `packet' to send any text string to the stub. For instance,
5074 maint packet heythere
5076 sends the packet "$heythere#<checksum>". Note that it is very easy to
5077 disrupt a debugging session by sending the wrong packet at the wrong
5080 The compare-sections command allows you to compare section data on the
5081 target to what is in the executable file without uploading or
5082 downloading, by comparing CRC checksums.
5084 * Tracing can collect general expressions
5086 You may now collect general expressions at tracepoints. This requires
5087 further additions to the target-side stub; see tracepoint.c and
5088 doc/agentexpr.texi for further details.
5090 * mask-address variable for Mips
5092 For Mips targets, you may control the zeroing of the upper 32 bits of
5093 a 64-bit address by entering `set mask-address on'. This is mainly
5094 of interest to users of embedded R4xxx and R5xxx processors.
5096 * Higher serial baud rates
5098 GDB's serial code now allows you to specify baud rates 57600, 115200,
5099 230400, and 460800 baud. (Note that your host system may not be able
5100 to achieve all of these rates.)
5104 The i960 configuration now includes an initial implementation of a
5105 builtin simulator, contributed by Jim Wilson.
5108 *** Changes in GDB-4.17:
5110 * New native configurations
5112 Alpha GNU/Linux alpha*-*-linux*
5113 Unixware 2.x i[3456]86-unixware2*
5114 Irix 6.x mips*-sgi-irix6*
5115 PowerPC GNU/Linux powerpc-*-linux*
5116 PowerPC Solaris powerpcle-*-solaris*
5117 Sparc GNU/Linux sparc-*-linux*
5118 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5122 Argonaut Risc Chip (ARC) arc-*-*
5123 Hitachi H8/300S h8300*-*-*
5124 Matsushita MN10200 w/simulator mn10200-*-*
5125 Matsushita MN10300 w/simulator mn10300-*-*
5126 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5127 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5128 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5129 Mitsubishi D10V w/simulator d10v-*-*
5130 Mitsubishi M32R/D w/simulator m32r-*-elf*
5131 Tsqware Sparclet sparclet-*-*
5132 NEC V850 w/simulator v850-*-*
5134 * New debugging protocols
5136 ARM with RDI protocol arm*-*-*
5137 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5138 DDB and LSI variants of PMON protocol mips*-*-*
5139 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5140 PowerPC with SDS protocol powerpc{,le}-*-eabi
5141 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5145 All configurations can now understand and use the DWARF 2 debugging
5146 format. The choice is automatic, if the symbol file contains DWARF 2
5151 GDB now includes basic Java language support. This support is
5152 only useful with Java compilers that produce native machine code.
5154 * solib-absolute-prefix and solib-search-path
5156 For SunOS and SVR4 shared libraries, you may now set the prefix for
5157 loading absolute shared library symbol files, and the search path for
5158 locating non-absolute shared library symbol files.
5160 * Live range splitting
5162 GDB can now effectively debug code for which GCC has performed live
5163 range splitting as part of its optimization. See gdb/doc/LRS for
5164 more details on the expected format of the stabs information.
5168 GDB's support for the GNU Hurd, including thread debugging, has been
5169 updated to work with current versions of the Hurd.
5173 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5174 instruction set. ARM GDB automatically detects when Thumb
5175 instructions are in use, and adjusts disassembly and backtracing
5180 GDB's MIPS target configurations now handle the MIP16 16-bit
5185 GDB now includes support for overlays; if an executable has been
5186 linked such that multiple sections are based at the same address, GDB
5187 will decide which section to use for symbolic info. You can choose to
5188 control the decision manually, using overlay commands, or implement
5189 additional target-side support and use "overlay load-target" to bring
5190 in the overlay mapping. Do "help overlay" for more detail.
5194 The command "info symbol <address>" displays information about
5195 the symbol at the specified address.
5199 The standard remote protocol now includes an extension that allows
5200 asynchronous collection and display of trace data. This requires
5201 extensive support in the target-side debugging stub. Tracing mode
5202 includes a new interaction mode in GDB and new commands: see the
5203 file tracepoint.c for more details.
5207 Configurations for embedded MIPS now include a simulator contributed
5208 by Cygnus Solutions. The simulator supports the instruction sets
5209 of most MIPS variants.
5213 Sparc configurations may now include the ERC32 simulator contributed
5214 by the European Space Agency. The simulator is not built into
5215 Sparc targets by default; configure with --enable-sim to include it.
5219 For target configurations that may include multiple variants of a
5220 basic architecture (such as MIPS and SH), you may now set the
5221 architecture explicitly. "set arch" sets, "info arch" lists
5222 the possible architectures.
5224 *** Changes in GDB-4.16:
5226 * New native configurations
5228 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5229 M68K NetBSD m68k-*-netbsd*
5230 PowerPC AIX 4.x powerpc-*-aix*
5231 PowerPC MacOS powerpc-*-macos*
5232 PowerPC Windows NT powerpcle-*-cygwin32
5233 RS/6000 AIX 4.x rs6000-*-aix4*
5237 ARM with RDP protocol arm-*-*
5238 I960 with MON960 i960-*-coff
5239 MIPS VxWorks mips*-*-vxworks*
5240 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5241 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5243 Matra Sparclet sparclet-*-*
5247 The powerpc-eabi configuration now includes the PSIM simulator,
5248 contributed by Andrew Cagney, with assistance from Mike Meissner.
5249 PSIM is a very elaborate model of the PowerPC, including not only
5250 basic instruction set execution, but also details of execution unit
5251 performance and I/O hardware. See sim/ppc/README for more details.
5255 GDB now works with Solaris 2.5.
5257 * Windows 95/NT native
5259 GDB will now work as a native debugger on Windows 95 and Windows NT.
5260 To build it from source, you must use the "gnu-win32" environment,
5261 which uses a DLL to emulate enough of Unix to run the GNU tools.
5262 Further information, binaries, and sources are available at
5263 ftp.cygnus.com, under pub/gnu-win32.
5265 * dont-repeat command
5267 If a user-defined command includes the command `dont-repeat', then the
5268 command will not be repeated if the user just types return. This is
5269 useful if the command is time-consuming to run, so that accidental
5270 extra keystrokes don't run the same command many times.
5272 * Send break instead of ^C
5274 The standard remote protocol now includes an option to send a break
5275 rather than a ^C to the target in order to interrupt it. By default,
5276 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5278 * Remote protocol timeout
5280 The standard remote protocol includes a new variable `remotetimeout'
5281 that allows you to set the number of seconds before GDB gives up trying
5282 to read from the target. The default value is 2.
5284 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5286 By default GDB will automatically keep track of objects as they are
5287 loaded and unloaded by the dynamic linker. By using the command `set
5288 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5289 when shared library events occur, thus allowing you to set breakpoints
5290 in shared libraries which are explicitly loaded by the inferior.
5292 Note this feature does not work on hpux8. On hpux9 you must link
5293 /usr/lib/end.o into your program. This feature should work
5294 automatically on hpux10.
5296 * Irix 5.x hardware watchpoint support
5298 Irix 5 configurations now support the use of hardware watchpoints.
5300 * Mips protocol "SYN garbage limit"
5302 When debugging a Mips target using the `target mips' protocol, you
5303 may set the number of characters that GDB will ignore by setting
5304 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5305 every character. The default value is 1050.
5307 * Recording and replaying remote debug sessions
5309 If you set `remotelogfile' to the name of a file, gdb will write to it
5310 a recording of a remote debug session. This recording may then be
5311 replayed back to gdb using "gdbreplay". See gdbserver/README for
5312 details. This is useful when you have a problem with GDB while doing
5313 remote debugging; you can make a recording of the session and send it
5314 to someone else, who can then recreate the problem.
5316 * Speedups for remote debugging
5318 GDB includes speedups for downloading and stepping MIPS systems using
5319 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5320 and more efficient S-record downloading.
5322 * Memory use reductions and statistics collection
5324 GDB now uses less memory and reports statistics about memory usage.
5325 Try the `maint print statistics' command, for example.
5327 *** Changes in GDB-4.15:
5329 * Psymtabs for XCOFF
5331 The symbol reader for AIX GDB now uses partial symbol tables. This
5332 can greatly improve startup time, especially for large executables.
5334 * Remote targets use caching
5336 Remote targets now use a data cache to speed up communication with the
5337 remote side. The data cache could lead to incorrect results because
5338 it doesn't know about volatile variables, thus making it impossible to
5339 debug targets which use memory mapped I/O devices. `set remotecache
5340 off' turns the the data cache off.
5342 * Remote targets may have threads
5344 The standard remote protocol now includes support for multiple threads
5345 in the target system, using new protocol commands 'H' and 'T'. See
5346 gdb/remote.c for details.
5350 If GDB is configured with `--enable-netrom', then it will include
5351 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5352 acts as though it is a bank of ROM on the target board, but you can
5353 write into it over the network. GDB's support consists only of
5354 support for fast loading into the emulated ROM; to debug, you must use
5355 another protocol, such as standard remote protocol. The usual
5356 sequence is something like
5358 target nrom <netrom-hostname>
5360 target remote <netrom-hostname>:1235
5364 GDB now includes support for the Apple Macintosh, as a host only. It
5365 may be run as either an MPW tool or as a standalone application, and
5366 it can debug through the serial port. All the usual GDB commands are
5367 available, but to the target command, you must supply "serial" as the
5368 device type instead of "/dev/ttyXX". See mpw-README in the main
5369 directory for more information on how to build. The MPW configuration
5370 scripts */mpw-config.in support only a few targets, and only the
5371 mips-idt-ecoff target has been tested.
5375 GDB configuration now uses autoconf. This is not user-visible,
5376 but does simplify configuration and building.
5380 GDB now supports hpux10.
5382 *** Changes in GDB-4.14:
5384 * New native configurations
5386 x86 FreeBSD i[345]86-*-freebsd
5387 x86 NetBSD i[345]86-*-netbsd
5388 NS32k NetBSD ns32k-*-netbsd
5389 Sparc NetBSD sparc-*-netbsd
5393 A29K VxWorks a29k-*-vxworks
5394 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5395 CPU32 EST-300 emulator m68*-*-est*
5396 PowerPC ELF powerpc-*-elf
5399 * Alpha OSF/1 support for procfs
5401 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5402 possible to attach to running processes. As the mounting of the /proc
5403 filesystem is optional on the Alpha, GDB automatically determines
5404 the availability of /proc during startup. This can lead to problems
5405 if /proc is unmounted after GDB has been started.
5407 * Arguments to user-defined commands
5409 User commands may accept up to 10 arguments separated by whitespace.
5410 Arguments are accessed within the user command via $arg0..$arg9. A
5413 print $arg0 + $arg1 + $arg2
5415 To execute the command use:
5418 Defines the command "adder" which prints the sum of its three arguments.
5419 Note the arguments are text substitutions, so they may reference variables,
5420 use complex expressions, or even perform inferior function calls.
5422 * New `if' and `while' commands
5424 This makes it possible to write more sophisticated user-defined
5425 commands. Both commands take a single argument, which is the
5426 expression to evaluate, and must be followed by the commands to
5427 execute, one per line, if the expression is nonzero, the list being
5428 terminated by the word `end'. The `if' command list may include an
5429 `else' word, which causes the following commands to be executed only
5430 if the expression is zero.
5432 * Fortran source language mode
5434 GDB now includes partial support for Fortran 77. It will recognize
5435 Fortran programs and can evaluate a subset of Fortran expressions, but
5436 variables and functions may not be handled correctly. GDB will work
5437 with G77, but does not yet know much about symbols emitted by other
5440 * Better HPUX support
5442 Most debugging facilities now work on dynamic executables for HPPAs
5443 running hpux9 or later. You can attach to running dynamically linked
5444 processes, but by default the dynamic libraries will be read-only, so
5445 for instance you won't be able to put breakpoints in them. To change
5446 that behavior do the following before running the program:
5452 This will cause the libraries to be mapped private and read-write.
5453 To revert to the normal behavior, do this:
5459 You cannot set breakpoints or examine data in the library until after
5460 the library is loaded if the function/data symbols do not have
5463 GDB can now also read debug symbols produced by the HP C compiler on
5464 HPPAs (sorry, no C++, Fortran or 68k support).
5466 * Target byte order now dynamically selectable
5468 You can choose which byte order to use with a target system, via the
5469 commands "set endian big" and "set endian little", and you can see the
5470 current setting by using "show endian". You can also give the command
5471 "set endian auto", in which case GDB will use the byte order
5472 associated with the executable. Currently, only embedded MIPS
5473 configurations support dynamic selection of target byte order.
5475 * New DOS host serial code
5477 This version uses DPMI interrupts to handle buffered I/O, so you
5478 no longer need to run asynctsr when debugging boards connected to
5481 *** Changes in GDB-4.13:
5483 * New "complete" command
5485 This lists all the possible completions for the rest of the line, if it
5486 were to be given as a command itself. This is intended for use by emacs.
5488 * Trailing space optional in prompt
5490 "set prompt" no longer adds a space for you after the prompt you set. This
5491 allows you to set a prompt which ends in a space or one that does not.
5493 * Breakpoint hit counts
5495 "info break" now displays a count of the number of times the breakpoint
5496 has been hit. This is especially useful in conjunction with "ignore"; you
5497 can ignore a large number of breakpoint hits, look at the breakpoint info
5498 to see how many times the breakpoint was hit, then run again, ignoring one
5499 less than that number, and this will get you quickly to the last hit of
5502 * Ability to stop printing at NULL character
5504 "set print null-stop" will cause GDB to stop printing the characters of
5505 an array when the first NULL is encountered. This is useful when large
5506 arrays actually contain only short strings.
5508 * Shared library breakpoints
5510 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5511 breakpoints in shared libraries before the executable is run.
5513 * Hardware watchpoints
5515 There is a new hardware breakpoint for the watch command for sparclite
5516 targets. See gdb/sparclite/hw_breakpoint.note.
5518 Hardware watchpoints are also now supported under GNU/Linux.
5522 Annotations have been added. These are for use with graphical interfaces,
5523 and are still experimental. Currently only gdba.el uses these.
5525 * Improved Irix 5 support
5527 GDB now works properly with Irix 5.2.
5529 * Improved HPPA support
5531 GDB now works properly with the latest GCC and GAS.
5533 * New native configurations
5535 Sequent PTX4 i[34]86-sequent-ptx4
5536 HPPA running OSF/1 hppa*-*-osf*
5537 Atari TT running SVR4 m68*-*-sysv4*
5538 RS/6000 LynxOS rs6000-*-lynxos*
5542 OS/9000 i[34]86-*-os9k
5543 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5546 * Hitachi SH7000 and E7000-PC ICE support
5548 There is now support for communicating with the Hitachi E7000-PC ICE.
5549 This is available automatically when GDB is configured for the SH.
5553 As usual, a variety of small fixes and improvements, both generic
5554 and configuration-specific. See the ChangeLog for more detail.
5556 *** Changes in GDB-4.12:
5558 * Irix 5 is now supported
5562 GDB-4.12 on the HPPA has a number of changes which make it unable
5563 to debug the output from the currently released versions of GCC and
5564 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5565 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5566 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5569 *** Changes in GDB-4.11:
5571 * User visible changes:
5575 The "set remotedebug" option is now consistent between the mips remote
5576 target, remote targets using the gdb-specific protocol, UDI (AMD's
5577 debug protocol for the 29k) and the 88k bug monitor. It is now an
5578 integer specifying a debug level (normally 0 or 1, but 2 means more
5579 debugging info for the mips target).
5581 * DEC Alpha native support
5583 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5584 debug info, but GDB works fairly well with the DEC compiler and should
5585 work with a future GCC release. See the README file for a few
5586 Alpha-specific notes.
5588 * Preliminary thread implementation
5590 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5592 * LynxOS native and target support for 386
5594 This release has been hosted on LynxOS 2.2, and also can be configured
5595 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5598 * Improvements in C++ mangling/demangling.
5600 This release has much better g++ debugging, specifically in name
5601 mangling/demangling, virtual function calls, print virtual table,
5602 call methods, ...etc.
5604 *** Changes in GDB-4.10:
5606 * User visible changes:
5608 Remote debugging using the GDB-specific (`target remote') protocol now
5609 supports the `load' command. This is only useful if you have some
5610 other way of getting the stub to the target system, and you can put it
5611 somewhere in memory where it won't get clobbered by the download.
5613 Filename completion now works.
5615 When run under emacs mode, the "info line" command now causes the
5616 arrow to point to the line specified. Also, "info line" prints
5617 addresses in symbolic form (as well as hex).
5619 All vxworks based targets now support a user settable option, called
5620 vxworks-timeout. This option represents the number of seconds gdb
5621 should wait for responses to rpc's. You might want to use this if
5622 your vxworks target is, perhaps, a slow software simulator or happens
5623 to be on the far side of a thin network line.
5627 This release contains support for using a DEC alpha as a GDB host for
5628 cross debugging. Native alpha debugging is not supported yet.
5631 *** Changes in GDB-4.9:
5635 This is the first GDB release which is accompanied by a matching testsuite.
5636 The testsuite requires installation of dejagnu, which should be available
5637 via ftp from most sites that carry GNU software.
5641 'Cfront' style demangling has had its name changed to 'ARM' style, to
5642 emphasize that it was written from the specifications in the C++ Annotated
5643 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5644 disclaimers, it still generated too much confusion with users attempting to
5645 use gdb with AT&T cfront.
5649 GDB now uses a standard remote interface to a simulator library.
5650 So far, the library contains simulators for the Zilog Z8001/2, the
5651 Hitachi H8/300, H8/500 and Super-H.
5653 * New targets supported
5655 H8/300 simulator h8300-hitachi-hms or h8300hms
5656 H8/500 simulator h8500-hitachi-hms or h8500hms
5657 SH simulator sh-hitachi-hms or sh
5658 Z8000 simulator z8k-zilog-none or z8ksim
5659 IDT MIPS board over serial line mips-idt-ecoff
5661 Cross-debugging to GO32 targets is supported. It requires a custom
5662 version of the i386-stub.c module which is integrated with the
5663 GO32 memory extender.
5665 * New remote protocols
5667 MIPS remote debugging protocol.
5669 * New source languages supported
5671 This version includes preliminary support for Chill, a Pascal like language
5672 used by telecommunications companies. Chill support is also being integrated
5673 into the GNU compiler, but we don't know when it will be publically available.
5676 *** Changes in GDB-4.8:
5678 * HP Precision Architecture supported
5680 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5681 version of this support was available as a set of patches from the
5682 University of Utah. GDB does not support debugging of programs
5683 compiled with the HP compiler, because HP will not document their file
5684 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5685 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5687 Many problems in the preliminary version have been fixed.
5689 * Faster and better demangling
5691 We have improved template demangling and fixed numerous bugs in the GNU style
5692 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5693 character types (wchar_t) are now supported. Demangling of each symbol is now
5694 only done once, and is cached when the symbol table for a file is read in.
5695 This results in a small increase in memory usage for C programs, a moderate
5696 increase in memory usage for C++ programs, and a fantastic speedup in
5699 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5700 from the specifications in the Annotated Reference Manual, which AT&T's
5701 compiler does not actually implement.
5703 * G++ multiple inheritance compiler problem
5705 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5706 inheritance lattices was reworked to properly discover ambiguities. We
5707 recently found an example which causes this new algorithm to fail in a
5708 very subtle way, producing bad debug information for those classes.
5709 The file 'gcc.patch' (in this directory) can be applied to gcc to
5710 circumvent the problem. A future GCC release will contain a complete
5713 The previous G++ debug info problem (mentioned below for the gdb-4.7
5714 release) is fixed in gcc version 2.3.2.
5716 * Improved configure script
5718 The `configure' script will now attempt to guess your system type if
5719 you don't supply a host system type. The old scheme of supplying a
5720 host system triplet is preferable over using this. All the magic is
5721 done in the new `config.guess' script. Examine it for details.
5723 We have also brought our configure script much more in line with the FSF's
5724 version. It now supports the --with-xxx options. In particular,
5725 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5726 The resulting GDB will not be able to read arbitrary object file formats --
5727 only the format ``expected'' to be used on the configured target system.
5728 We hope to make this the default in a future release.
5730 * Documentation improvements
5732 There's new internal documentation on how to modify GDB, and how to
5733 produce clean changes to the code. We implore people to read it
5734 before submitting changes.
5736 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5737 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5738 `info' files are also provided. To build `info' files from scratch,
5739 you will need the latest `makeinfo' release, which will be available in
5740 a future texinfo-X.Y release.
5742 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5743 We're not sure exactly which versions have this problem, but it has
5744 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5745 or better. If that isn't possible, there is a patch in
5746 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5747 around this problem.
5751 GDB now supports array constants that can be used in expressions typed in by
5752 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5753 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5756 The new directory `gdb/sparclite' contains a program that demonstrates
5757 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5759 * New native hosts supported
5761 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5762 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5764 * New targets supported
5766 AMD 29k family via UDI a29k-amd-udi or udi29k
5768 * New file formats supported
5770 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5771 HPUX core files, and SCO 3.2v2 core files.
5775 Attaching to processes now works again; thanks for the many bug reports.
5777 We have also stomped on a bunch of core dumps caused by
5778 printf_filtered("%s") problems.
5780 We eliminated a copyright problem on the rpc and ptrace header files
5781 for VxWorks, which was discovered at the last minute during the 4.7
5782 release. You should now be able to build a VxWorks GDB.
5784 You can now interrupt gdb while an attached process is running. This
5785 will cause the attached process to stop, and give control back to GDB.
5787 We fixed problems caused by using too many file descriptors
5788 for reading symbols from object files and libraries. This was
5789 especially a problem for programs that used many (~100) shared
5792 The `step' command now only enters a subroutine if there is line number
5793 information for the subroutine. Otherwise it acts like the `next'
5794 command. Previously, `step' would enter subroutines if there was
5795 any debugging information about the routine. This avoids problems
5796 when using `cc -g1' on MIPS machines.
5798 * Internal improvements
5800 GDB's internal interfaces have been improved to make it easier to support
5801 debugging of multiple languages in the future.
5803 GDB now uses a common structure for symbol information internally.
5804 Minimal symbols (derived from linkage symbols in object files), partial
5805 symbols (from a quick scan of debug information), and full symbols
5806 contain a common subset of information, making it easier to write
5807 shared code that handles any of them.
5809 * New command line options
5811 We now accept --silent as an alias for --quiet.
5815 The memory-mapped-malloc library is now licensed under the GNU Library
5816 General Public License.
5818 *** Changes in GDB-4.7:
5820 * Host/native/target split
5822 GDB has had some major internal surgery to untangle the support for
5823 hosts and remote targets. Now, when you configure GDB for a remote
5824 target, it will no longer load in all of the support for debugging
5825 local programs on the host. When fully completed and tested, this will
5826 ensure that arbitrary host/target combinations are possible.
5828 The primary conceptual shift is to separate the non-portable code in
5829 GDB into three categories. Host specific code is required any time GDB
5830 is compiled on that host, regardless of the target. Target specific
5831 code relates to the peculiarities of the target, but can be compiled on
5832 any host. Native specific code is everything else: it can only be
5833 built when the host and target are the same system. Child process
5834 handling and core file support are two common `native' examples.
5836 GDB's use of /proc for controlling Unix child processes is now cleaner.
5837 It has been split out into a single module under the `target_ops' vector,
5838 plus two native-dependent functions for each system that uses /proc.
5840 * New hosts supported
5842 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5843 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5844 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5846 * New targets supported
5848 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5849 68030 and CPU32 m68030-*-*, m68332-*-*
5851 * New native hosts supported
5853 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5854 (386bsd is not well tested yet)
5855 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5857 * New file formats supported
5859 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5860 supports reading of `a.out.adobe' object files, which are an a.out
5861 format extended with minimal information about multiple sections.
5865 `show copying' is the same as the old `info copying'.
5866 `show warranty' is the same as `info warrantee'.
5867 These were renamed for consistency. The old commands continue to work.
5869 `info handle' is a new alias for `info signals'.
5871 You can now define pre-command hooks, which attach arbitrary command
5872 scripts to any command. The commands in the hook will be executed
5873 prior to the user's command. You can also create a hook which will be
5874 executed whenever the program stops. See gdb.texinfo.
5878 We now deal with Cfront style name mangling, and can even extract type
5879 info from mangled symbols. GDB can automatically figure out which
5880 symbol mangling style your C++ compiler uses.
5882 Calling of methods and virtual functions has been improved as well.
5886 The crash that occured when debugging Sun Ansi-C compiled binaries is
5887 fixed. This was due to mishandling of the extra N_SO stabs output
5890 We also finally got Ultrix 4.2 running in house, and fixed core file
5891 support, with help from a dozen people on the net.
5893 John M. Farrell discovered that the reason that single-stepping was so
5894 slow on all of the Mips based platforms (primarily SGI and DEC) was
5895 that we were trying to demangle and lookup a symbol used for internal
5896 purposes on every instruction that was being stepped through. Changing
5897 the name of that symbol so that it couldn't be mistaken for a C++
5898 mangled symbol sped things up a great deal.
5900 Rich Pixley sped up symbol lookups in general by getting much smarter
5901 about when C++ symbol mangling is necessary. This should make symbol
5902 completion (TAB on the command line) much faster. It's not as fast as
5903 we'd like, but it's significantly faster than gdb-4.6.
5907 A new user controllable variable 'call_scratch_address' can
5908 specify the location of a scratch area to be used when GDB
5909 calls a function in the target. This is necessary because the
5910 usual method of putting the scratch area on the stack does not work
5911 in systems that have separate instruction and data spaces.
5913 We integrated changes to support the 29k UDI (Universal Debugger
5914 Interface), but discovered at the last minute that we didn't have all
5915 of the appropriate copyright paperwork. We are working with AMD to
5916 resolve this, and hope to have it available soon.
5920 We have sped up the remote serial line protocol, especially for targets
5921 with lots of registers. It now supports a new `expedited status' ('T')
5922 message which can be used in place of the existing 'S' status message.
5923 This allows the remote stub to send only the registers that GDB
5924 needs to make a quick decision about single-stepping or conditional
5925 breakpoints, eliminating the need to fetch the entire register set for
5926 each instruction being stepped through.
5928 The GDB remote serial protocol now implements a write-through cache for
5929 registers, only re-reading the registers if the target has run.
5931 There is also a new remote serial stub for SPARC processors. You can
5932 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5933 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5934 processor with a serial port.
5938 Configure.in files have become much easier to read and modify. A new
5939 `table driven' format makes it more obvious what configurations are
5940 supported, and what files each one uses.
5944 There is a new opcodes library which will eventually contain all of the
5945 disassembly routines and opcode tables. At present, it only contains
5946 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5947 disassembler (binutils/objdump) to share these routines.
5949 The libiberty library is now copylefted under the GNU Library General
5950 Public License. This allows more liberal use, and was done so libg++
5951 can use it. This makes no difference to GDB, since the Library License
5952 grants all the rights from the General Public License.
5956 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5957 reference to the stabs symbol info used by the debugger. It is (as far
5958 as we know) the only published document on this fascinating topic. We
5959 encourage you to read it, compare it to the stabs information on your
5960 system, and send improvements on the document in general (to
5961 bug-gdb@prep.ai.mit.edu).
5963 And, of course, many bugs have been fixed.
5966 *** Changes in GDB-4.6:
5968 * Better support for C++ function names
5970 GDB now accepts as input the "demangled form" of C++ overloaded function
5971 names and member function names, and can do command completion on such names
5972 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5973 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5974 Make use of command completion, it is your friend.
5976 GDB also now accepts a variety of C++ mangled symbol formats. They are
5977 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5978 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5979 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5980 for the list of formats.
5982 * G++ symbol mangling problem
5984 Recent versions of gcc have a bug in how they emit debugging information for
5985 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5986 directory) can be applied to gcc to fix the problem. Alternatively, if you
5987 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5988 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5989 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5992 * New 'maintenance' command
5994 All of the commands related to hacking GDB internals have been moved out of
5995 the main command set, and now live behind the 'maintenance' command. This
5996 can also be abbreviated as 'mt'. The following changes were made:
5998 dump-me -> maintenance dump-me
5999 info all-breakpoints -> maintenance info breakpoints
6000 printmsyms -> maintenance print msyms
6001 printobjfiles -> maintenance print objfiles
6002 printpsyms -> maintenance print psymbols
6003 printsyms -> maintenance print symbols
6005 The following commands are new:
6007 maintenance demangle Call internal GDB demangler routine to
6008 demangle a C++ link name and prints the result.
6009 maintenance print type Print a type chain for a given symbol
6011 * Change to .gdbinit file processing
6013 We now read the $HOME/.gdbinit file before processing the argv arguments
6014 (e.g. reading symbol files or core files). This allows global parameters to
6015 be set, which will apply during the symbol reading. The ./.gdbinit is still
6016 read after argv processing.
6018 * New hosts supported
6020 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6022 GNU/Linux support i386-unknown-linux or linux
6024 We are also including code to support the HP/PA running BSD and HPUX. This
6025 is almost guaranteed not to work, as we didn't have time to test or build it
6026 for this release. We are including it so that the more adventurous (or
6027 masochistic) of you can play with it. We also had major problems with the
6028 fact that the compiler that we got from HP doesn't support the -g option.
6031 * New targets supported
6033 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6035 * More smarts about finding #include files
6037 GDB now remembers the compilation directory for all include files, and for
6038 all files from which C is generated (like yacc and lex sources). This
6039 greatly improves GDB's ability to find yacc/lex sources, and include files,
6040 especially if you are debugging your program from a directory different from
6041 the one that contains your sources.
6043 We also fixed a bug which caused difficulty with listing and setting
6044 breakpoints in include files which contain C code. (In the past, you had to
6045 try twice in order to list an include file that you hadn't looked at before.)
6047 * Interesting infernals change
6049 GDB now deals with arbitrary numbers of sections, where the symbols for each
6050 section must be relocated relative to that section's landing place in the
6051 target's address space. This work was needed to support ELF with embedded
6052 stabs used by Solaris-2.0.
6054 * Bug fixes (of course!)
6056 There have been loads of fixes for the following things:
6057 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6058 i960, stabs, DOS(GO32), procfs, etc...
6060 See the ChangeLog for details.
6062 *** Changes in GDB-4.5:
6064 * New machines supported (host and target)
6066 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6068 SGI Irix-4.x mips-sgi-irix4 or iris4
6070 * New malloc package
6072 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6073 Mmalloc is capable of handling mutiple heaps of memory. It is also
6074 capable of saving a heap to a file, and then mapping it back in later.
6075 This can be used to greatly speedup the startup of GDB by using a
6076 pre-parsed symbol table which lives in a mmalloc managed heap. For
6077 more details, please read mmalloc/mmalloc.texi.
6081 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6082 'help info proc' for details.
6084 * MIPS ecoff symbol table format
6086 The code that reads MIPS symbol table format is now supported on all hosts.
6087 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6090 * File name changes for MS-DOS
6092 Many files in the config directories have been renamed to make it easier to
6093 support GDB on MS-DOSe systems (which have very restrictive file name
6094 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6095 environment) is close to working but has some remaining problems. Note
6096 that debugging of DOS programs is not supported, due to limitations
6097 in the ``operating system'', but it can be used to host cross-debugging.
6099 * Cross byte order fixes
6101 Many fixes have been made to support cross debugging of Sparc and MIPS
6102 targets from hosts whose byte order differs.
6104 * New -mapped and -readnow options
6106 If memory-mapped files are available on your system through the 'mmap'
6107 system call, you can use the -mapped option on the `file' or
6108 `symbol-file' commands to cause GDB to write the symbols from your
6109 program into a reusable file. If the program you are debugging is
6110 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6111 Future GDB debugging sessions will notice the presence of this file,
6112 and will quickly map in symbol information from it, rather than reading
6113 the symbol table from the executable program. Using the '-mapped'
6114 option in a GDB `file' or `symbol-file' command has the same effect as
6115 starting GDB with the '-mapped' command-line option.
6117 You can cause GDB to read the entire symbol table immediately by using
6118 the '-readnow' option with any of the commands that load symbol table
6119 information (or on the GDB command line). This makes the command
6120 slower, but makes future operations faster.
6122 The -mapped and -readnow options are typically combined in order to
6123 build a `fred.syms' file that contains complete symbol information.
6124 A simple GDB invocation to do nothing but build a `.syms' file for future
6127 gdb -batch -nx -mapped -readnow programname
6129 The `.syms' file is specific to the host machine on which GDB is run.
6130 It holds an exact image of GDB's internal symbol table. It cannot be
6131 shared across multiple host platforms.
6133 * longjmp() handling
6135 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6136 siglongjmp() without losing control. This feature has not yet been ported to
6137 all systems. It currently works on many 386 platforms, all MIPS-based
6138 platforms (SGI, DECstation, etc), and Sun3/4.
6142 Preliminary work has been put in to support the new Solaris OS from Sun. At
6143 this time, it can control and debug processes, but it is not capable of
6148 As always, many many bug fixes. The major areas were with g++, and mipsread.
6149 People using the MIPS-based platforms should experience fewer mysterious
6150 crashes and trashed symbol tables.
6152 *** Changes in GDB-4.4:
6154 * New machines supported (host and target)
6156 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6158 BSD Reno on Vax vax-dec-bsd
6159 Ultrix on Vax vax-dec-ultrix
6161 * New machines supported (target)
6163 AMD 29000 embedded, using EBMON a29k-none-none
6167 GDB continues to improve its handling of C++. `References' work better.
6168 The demangler has also been improved, and now deals with symbols mangled as
6169 per the Annotated C++ Reference Guide.
6171 GDB also now handles `stabs' symbol information embedded in MIPS
6172 `ecoff' symbol tables. Since the ecoff format was not easily
6173 extensible to handle new languages such as C++, this appeared to be a
6174 good way to put C++ debugging info into MIPS binaries. This option
6175 will be supported in the GNU C compiler, version 2, when it is
6178 * New features for SVR4
6180 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6181 shared libraries. Debugging dynamically linked programs should present
6182 only minor differences from debugging statically linked programs.
6184 The `info proc' command will print out information about any process
6185 on an SVR4 system (including the one you are debugging). At the moment,
6186 it prints the address mappings of the process.
6188 If you bring up GDB on another SVR4 system, please send mail to
6189 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6191 * Better dynamic linking support in SunOS
6193 Reading symbols from shared libraries which contain debugging symbols
6194 now works properly. However, there remain issues such as automatic
6195 skipping of `transfer vector' code during function calls, which
6196 make it harder to debug code in a shared library, than to debug the
6197 same code linked statically.
6201 GDB is now using the latest `getopt' routines from the FSF. This
6202 version accepts the -- prefix for options with long names. GDB will
6203 continue to accept the old forms (-option and +option) as well.
6204 Various single letter abbreviations for options have been explicity
6205 added to the option table so that they won't get overshadowed in the
6206 future by other options that begin with the same letter.
6210 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6211 Many assorted bugs have been handled. Many more remain to be handled.
6212 See the various ChangeLog files (primarily in gdb and bfd) for details.
6215 *** Changes in GDB-4.3:
6217 * New machines supported (host and target)
6219 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6220 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6221 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6223 * Almost SCO Unix support
6225 We had hoped to support:
6226 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6227 (except for core file support), but we discovered very late in the release
6228 that it has problems with process groups that render gdb unusable. Sorry
6229 about that. I encourage people to fix it and post the fixes.
6231 * Preliminary ELF and DWARF support
6233 GDB can read ELF object files on System V Release 4, and can handle
6234 debugging records for C, in DWARF format, in ELF files. This support
6235 is preliminary. If you bring up GDB on another SVR4 system, please
6236 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6241 GDB now uses the latest `readline' library. One user-visible change
6242 is that two tabs will list possible command completions, which previously
6243 required typing M-? (meta-question mark, or ESC ?).
6247 The `stepi' bug that many of you noticed has been squashed.
6248 Many bugs in C++ have been handled. Many more remain to be handled.
6249 See the various ChangeLog files (primarily in gdb and bfd) for details.
6251 * State of the MIPS world (in case you wondered):
6253 GDB can understand the symbol tables emitted by the compilers
6254 supplied by most vendors of MIPS-based machines, including DEC. These
6255 symbol tables are in a format that essentially nobody else uses.
6257 Some versions of gcc come with an assembler post-processor called
6258 mips-tfile. This program is required if you want to do source-level
6259 debugging of gcc-compiled programs. I believe FSF does not ship
6260 mips-tfile with gcc version 1, but it will eventually come with gcc
6263 Debugging of g++ output remains a problem. g++ version 1.xx does not
6264 really support it at all. (If you're lucky, you should be able to get
6265 line numbers and stack traces to work, but no parameters or local
6266 variables.) With some work it should be possible to improve the
6269 When gcc version 2 is released, you will have somewhat better luck.
6270 However, even then you will get confusing results for inheritance and
6273 We will eventually provide full debugging of g++ output on
6274 DECstations. This will probably involve some kind of stabs-in-ecoff
6275 encapulation, but the details have not been worked out yet.
6278 *** Changes in GDB-4.2:
6280 * Improved configuration
6282 Only one copy of `configure' exists now, and it is not self-modifying.
6283 Porting BFD is simpler.
6287 The `step' and `next' commands now only stop at the first instruction
6288 of a source line. This prevents the multiple stops that used to occur
6289 in switch statements, for-loops, etc. `Step' continues to stop if a
6290 function that has debugging information is called within the line.
6294 Lots of small bugs fixed. More remain.
6296 * New host supported (not target)
6298 Intel 386 PC clone running Mach i386-none-mach
6301 *** Changes in GDB-4.1:
6303 * Multiple source language support
6305 GDB now has internal scaffolding to handle several source languages.
6306 It determines the type of each source file from its filename extension,
6307 and will switch expression parsing and number formatting to match the
6308 language of the function in the currently selected stack frame.
6309 You can also specifically set the language to be used, with
6310 `set language c' or `set language modula-2'.
6314 GDB now has preliminary support for the GNU Modula-2 compiler,
6315 currently under development at the State University of New York at
6316 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6317 continue through the fall of 1991 and into 1992.
6319 Other Modula-2 compilers are currently not supported, and attempting to
6320 debug programs compiled with them will likely result in an error as the
6321 symbol table is read. Feel free to work on it, though!
6323 There are hooks in GDB for strict type checking and range checking,
6324 in the `Modula-2 philosophy', but they do not currently work.
6328 GDB can now write to executable and core files (e.g. patch
6329 a variable's value). You must turn this switch on, specify
6330 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6331 by assigning a new value to a variable. Modifications take
6334 * Automatic SunOS shared library reading
6336 When you run your program, GDB automatically determines where its
6337 shared libraries (if any) have been loaded, and reads their symbols.
6338 The `share' command is no longer needed. This also works when
6339 examining core files.
6343 You can specify the number of lines that the `list' command shows.
6346 * New machines supported (host and target)
6348 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6349 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6350 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6352 * New hosts supported (not targets)
6354 IBM RT/PC: romp-ibm-aix or rtpc
6356 * New targets supported (not hosts)
6358 AMD 29000 embedded with COFF a29k-none-coff
6359 AMD 29000 embedded with a.out a29k-none-aout
6360 Ultracomputer remote kernel debug a29k-nyu-kern
6362 * New remote interfaces
6368 *** Changes in GDB-4.0:
6372 Wide output is wrapped at good places to make the output more readable.
6374 Gdb now supports cross-debugging from a host machine of one type to a
6375 target machine of another type. Communication with the target system
6376 is over serial lines. The ``target'' command handles connecting to the
6377 remote system; the ``load'' command will download a program into the
6378 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6379 also supports debugging of realtime processes running under VxWorks,
6380 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6381 stub on the target system.
6383 New CPUs supported include the AMD 29000 and Intel 960.
6385 GDB now reads object files and symbol tables via a ``binary file''
6386 library, which allows a single copy of GDB to debug programs of multiple
6387 object file types such as a.out and coff.
6389 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6390 refcard.dvi and refcard.ps are available to format it).
6393 * Control-Variable user interface simplified
6395 All variables that control the operation of the debugger can be set
6396 by the ``set'' command, and displayed by the ``show'' command.
6398 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6399 ``Show prompt'' produces the response:
6400 Gdb's prompt is new-gdb=>.
6402 What follows are the NEW set commands. The command ``help set'' will
6403 print a complete list of old and new set commands. ``help set FOO''
6404 will give a longer description of the variable FOO. ``show'' will show
6405 all of the variable descriptions and their current settings.
6407 confirm on/off: Enables warning questions for operations that are
6408 hard to recover from, e.g. rerunning the program while
6409 it is already running. Default is ON.
6411 editing on/off: Enables EMACS style command line editing
6412 of input. Previous lines can be recalled with
6413 control-P, the current line can be edited with control-B,
6414 you can search for commands with control-R, etc.
6417 history filename NAME: NAME is where the gdb command history
6418 will be stored. The default is .gdb_history,
6419 or the value of the environment variable
6422 history size N: The size, in commands, of the command history. The
6423 default is 256, or the value of the environment variable
6426 history save on/off: If this value is set to ON, the history file will
6427 be saved after exiting gdb. If set to OFF, the
6428 file will not be saved. The default is OFF.
6430 history expansion on/off: If this value is set to ON, then csh-like
6431 history expansion will be performed on
6432 command line input. The default is OFF.
6434 radix N: Sets the default radix for input and output. It can be set
6435 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6436 in the current radix, so "set radix 10" is always a no-op.
6438 height N: This integer value is the number of lines on a page. Default
6439 is 24, the current `stty rows'' setting, or the ``li#''
6440 setting from the termcap entry matching the environment
6443 width N: This integer value is the number of characters on a line.
6444 Default is 80, the current `stty cols'' setting, or the ``co#''
6445 setting from the termcap entry matching the environment
6448 Note: ``set screensize'' is obsolete. Use ``set height'' and
6449 ``set width'' instead.
6451 print address on/off: Print memory addresses in various command displays,
6452 such as stack traces and structure values. Gdb looks
6453 more ``symbolic'' if you turn this off; it looks more
6454 ``machine level'' with it on. Default is ON.
6456 print array on/off: Prettyprint arrays. New convenient format! Default
6459 print demangle on/off: Print C++ symbols in "source" form if on,
6462 print asm-demangle on/off: Same, for assembler level printouts
6465 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6468 * Support for Epoch Environment.
6470 The epoch environment is a version of Emacs v18 with windowing. One
6471 new command, ``inspect'', is identical to ``print'', except that if you
6472 are running in the epoch environment, the value is printed in its own
6476 * Support for Shared Libraries
6478 GDB can now debug programs and core files that use SunOS shared libraries.
6479 Symbols from a shared library cannot be referenced
6480 before the shared library has been linked with the program (this
6481 happens after you type ``run'' and before the function main() is entered).
6482 At any time after this linking (including when examining core files
6483 from dynamically linked programs), gdb reads the symbols from each
6484 shared library when you type the ``sharedlibrary'' command.
6485 It can be abbreviated ``share''.
6487 sharedlibrary REGEXP: Load shared object library symbols for files
6488 matching a unix regular expression. No argument
6489 indicates to load symbols for all shared libraries.
6491 info sharedlibrary: Status of loaded shared libraries.
6496 A watchpoint stops execution of a program whenever the value of an
6497 expression changes. Checking for this slows down execution
6498 tremendously whenever you are in the scope of the expression, but is
6499 quite useful for catching tough ``bit-spreader'' or pointer misuse
6500 problems. Some machines such as the 386 have hardware for doing this
6501 more quickly, and future versions of gdb will use this hardware.
6503 watch EXP: Set a watchpoint (breakpoint) for an expression.
6505 info watchpoints: Information about your watchpoints.
6507 delete N: Deletes watchpoint number N (same as breakpoints).
6508 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6509 enable N: Re-enables watchpoint number N (same as breakpoints).
6512 * C++ multiple inheritance
6514 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6517 * C++ exception handling
6519 Gdb now supports limited C++ exception handling. Besides the existing
6520 ability to breakpoint on an exception handler, gdb can breakpoint on
6521 the raising of an exception (before the stack is peeled back to the
6524 catch FOO: If there is a FOO exception handler in the dynamic scope,
6525 set a breakpoint to catch exceptions which may be raised there.
6526 Multiple exceptions (``catch foo bar baz'') may be caught.
6528 info catch: Lists all exceptions which may be caught in the
6529 current stack frame.
6532 * Minor command changes
6534 The command ``call func (arg, arg, ...)'' now acts like the print
6535 command, except it does not print or save a value if the function's result
6536 is void. This is similar to dbx usage.
6538 The ``up'' and ``down'' commands now always print the frame they end up
6539 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6540 frames without printing.
6542 * New directory command
6544 'dir' now adds directories to the FRONT of the source search path.
6545 The path starts off empty. Source files that contain debug information
6546 about the directory in which they were compiled can be found even
6547 with an empty path; Sun CC and GCC include this information. If GDB can't
6548 find your source file in the current directory, type "dir .".
6550 * Configuring GDB for compilation
6552 For normal use, type ``./configure host''. See README or gdb.texinfo
6555 GDB now handles cross debugging. If you are remotely debugging between
6556 two different machines, type ``./configure host -target=targ''.
6557 Host is the machine where GDB will run; targ is the machine
6558 where the program that you are debugging will run.
projects / external / binutils.git / blob