1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.11
6 * GDB now supports a negative repeat count in the 'x' command to examine
7 memory backward from the given address. For example:
10 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
11 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
12 (gdb) x/-5i 0x0000000000400580
13 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
14 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
15 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
16 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
17 0x40057b <main(int, char**)+25>:
18 callq 0x400536 <Func1(int, char const*)>
20 * Fortran: Support structures with fields of dynamic types and
21 arrays of dynamic types.
23 * GDB now supports multibit bitfields and enums in target register
26 * New Python-based convenience function $_as_string(val), which returns
27 the textual representation of a value. This function is especially
28 useful to obtain the text label of an enum value.
30 * Intel MPX bound violation handling.
32 Segmentation faults caused by a Intel MPX boundary violation
33 now display the kind of violation (upper or lower), the memory
34 address accessed and the memory bounds, along with the usual
35 signal received and code location.
39 Program received signal SIGSEGV, Segmentation fault
40 Upper bound violation while accessing address 0x7fffffffc3b3
41 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
42 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
44 * Rust language support.
45 GDB now supports debugging programs written in the Rust programming
46 language. See https://www.rust-lang.org/ for more information about
49 * Support for running interpreters on specified input/output devices
51 GDB now supports a new mechanism that allows frontends to provide
52 fully featured GDB console views, as a better alternative to
53 building such views on top of the "-interpreter-exec console"
54 command. See the new "new-ui" command below. With that command,
55 frontends can now start GDB in the traditional command-line mode
56 running in an embedded terminal emulator widget, and create a
57 separate MI interpreter running on a specified i/o device. In this
58 way, GDB handles line editing, history, tab completion, etc. in the
59 console all by itself, and the GUI uses the separate MI interpreter
60 for its own control and synchronization, invisible to the command
66 skip -gfile file-glob-pattern
67 skip -function function
68 skip -rfunction regular-expression
69 A generalized form of the skip command, with new support for
70 glob-style file names and regular expressions for function names.
71 Additionally, a file spec and a function spec may now be combined.
73 maint info line-table REGEXP
74 Display the contents of GDB's internal line table data struture.
77 Run any GDB unit tests that were compiled in.
80 Start a new user interface instance running INTERP as interpreter,
81 using the TTY file for input/output.
85 ** gdb.Breakpoint objects have a new attribute "pending", which
86 indicates whether the breakpoint is pending.
89 Signal ("set") the given MS-Windows event object. This is used in
90 conjunction with the Windows JIT debugging (AeDebug) support, where
91 the OS suspends a crashing process until a debugger can attach to
92 it. Resuming the crashing process, in order to debug it, is done by
95 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
96 was added in GDBserver, including JIT compiling fast tracepoint's
97 conditional expression bytecode into native code.
99 * Support for various remote target protocols and ROM monitors has
102 target m32rsdi Remote M32R debugging over SDI
103 target mips MIPS remote debugging protocol
104 target pmon PMON ROM monitor
105 target ddb NEC's DDB variant of PMON for Vr4300
106 target rockhopper NEC RockHopper variant of PMON
107 target lsi LSI variant of PMO
109 * Support for tracepoints and fast tracepoints on powerpc-linux,
110 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
111 including JIT compiling fast tracepoint's conditional expression
112 bytecode into native code.
114 * MI async record =record-started now includes the method and format used for
115 recording. For example:
117 =record-started,thread-group="i1",method="btrace",format="bts"
121 Andes NDS32 nds32*-*-elf
123 *** Changes in GDB 7.11
125 * GDB now supports debugging kernel-based threads on FreeBSD.
127 * Per-inferior thread numbers
129 Thread numbers are now per inferior instead of global. If you're
130 debugging multiple inferiors, GDB displays thread IDs using a
131 qualified INF_NUM.THR_NUM form. For example:
135 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
136 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
137 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
138 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
140 As consequence, thread numbers as visible in the $_thread
141 convenience variable and in Python's InferiorThread.num attribute
142 are no longer unique between inferiors.
144 GDB now maintains a second thread ID per thread, referred to as the
145 global thread ID, which is the new equivalent of thread numbers in
146 previous releases. See also $_gthread below.
148 For backwards compatibility, MI's thread IDs always refer to global
151 * Commands that accept thread IDs now accept the qualified
152 INF_NUM.THR_NUM form as well. For example:
155 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
158 * In commands that accept a list of thread IDs, you can now refer to
159 all threads of an inferior using a star wildcard. GDB accepts
160 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
161 refer to all threads of the current inferior. For example, "info
164 * You can use "info threads -gid" to display the global thread ID of
167 * The new convenience variable $_gthread holds the global number of
170 * The new convenience variable $_inferior holds the number of the
173 * GDB now displays the ID and name of the thread that hit a breakpoint
174 or received a signal, if your program is multi-threaded. For
177 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
178 Thread 1 "main" received signal SIGINT, Interrupt.
180 * Record btrace now supports non-stop mode.
182 * Support for tracepoints on aarch64-linux was added in GDBserver.
184 * The 'record instruction-history' command now indicates speculative execution
185 when using the Intel Processor Trace recording format.
187 * GDB now allows users to specify explicit locations, bypassing
188 the linespec parser. This feature is also available to GDB/MI
191 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
192 GDB now is able to debug both AArch64 applications and ARM applications
195 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
196 including JIT compiling fast tracepoint's conditional expression bytecode
199 * GDB now supports displaced stepping on AArch64 GNU/Linux.
201 * "info threads", "info inferiors", "info display", "info checkpoints"
202 and "maint info program-spaces" now list the corresponding items in
203 ascending ID order, for consistency with all other "info" commands.
205 * In Ada, the overloads selection menu has been enhanced to display the
206 parameter types and the return types for the matching overloaded subprograms.
210 maint set target-non-stop (on|off|auto)
211 maint show target-non-stop
212 Control whether GDB targets always operate in non-stop mode even if
213 "set non-stop" is "off". The default is "auto", meaning non-stop
214 mode is enabled if supported by the target.
216 maint set bfd-sharing
217 maint show bfd-sharing
218 Control the reuse of bfd objects.
222 Control display of debugging info regarding bfd caching.
226 Control display of debugging info regarding FreeBSD threads.
228 set remote multiprocess-extensions-packet
229 show remote multiprocess-extensions-packet
230 Set/show the use of the remote protocol multiprocess extensions.
232 set remote thread-events
233 show remote thread-events
234 Set/show the use of thread create/exit events.
236 set ada print-signatures on|off
237 show ada print-signatures"
238 Control whether parameter types and return types are displayed in overloads
239 selection menus. It is activaled (@code{on}) by default.
243 Controls the maximum size of memory, in bytes, that GDB will
244 allocate for value contents. Prevents incorrect programs from
245 causing GDB to allocate overly large buffers. Default is 64k.
247 * The "disassemble" command accepts a new modifier: /s.
248 It prints mixed source+disassembly like /m with two differences:
249 - disassembled instructions are now printed in program order, and
250 - and source for all relevant files is now printed.
251 The "/m" option is now considered deprecated: its "source-centric"
252 output hasn't proved useful in practice.
254 * The "record instruction-history" command accepts a new modifier: /s.
255 It behaves exactly like /m and prints mixed source+disassembly.
257 * The "set scheduler-locking" command supports a new mode "replay".
258 It behaves like "off" in record mode and like "on" in replay mode.
260 * Support for various ROM monitors has been removed:
262 target dbug dBUG ROM monitor for Motorola ColdFire
263 target picobug Motorola picobug monitor
264 target dink32 DINK32 ROM monitor for PowerPC
265 target m32r Renesas M32R/D ROM monitor
266 target mon2000 mon2000 ROM monitor
267 target ppcbug PPCBUG ROM monitor for PowerPC
269 * Support for reading/writing memory and extracting values on architectures
270 whose memory is addressable in units of any integral multiple of 8 bits.
275 Indicates that an exec system call was executed.
277 exec-events feature in qSupported
278 The qSupported packet allows GDB to request support for exec
279 events using the new 'gdbfeature' exec-event, and the qSupported
280 response can contain the corresponding 'stubfeature'. Set and
281 show commands can be used to display whether these features are enabled.
284 Equivalent to interrupting with the ^C character, but works in
287 thread created stop reason (T05 create:...)
288 Indicates that the thread was just created and is stopped at entry.
290 thread exit stop reply (w exitcode;tid)
291 Indicates that the thread has terminated.
294 Enables/disables thread create and exit event reporting. For
295 example, this is used in non-stop mode when GDB stops a set of
296 threads and synchronously waits for the their corresponding stop
297 replies. Without exit events, if one of the threads exits, GDB
298 would hang forever not knowing that it should no longer expect a
299 stop for that same thread.
302 Indicates that there are no resumed threads left in the target (all
303 threads are stopped). The remote stub reports support for this stop
304 reply to GDB's qSupported query.
307 Enables/disables catching syscalls from the inferior process.
308 The remote stub reports support for this packet to GDB's qSupported query.
310 syscall_entry stop reason
311 Indicates that a syscall was just called.
313 syscall_return stop reason
314 Indicates that a syscall just returned.
316 * Extended-remote exec events
318 ** GDB now has support for exec events on extended-remote Linux targets.
319 For such targets with Linux kernels 2.5.46 and later, this enables
320 follow-exec-mode and exec catchpoints.
322 set remote exec-event-feature-packet
323 show remote exec-event-feature-packet
324 Set/show the use of the remote exec event feature.
326 * Thread names in remote protocol
328 The reply to qXfer:threads:read may now include a name attribute for each
331 * Target remote mode fork and exec events
333 ** GDB now has support for fork and exec events on target remote mode
334 Linux targets. For such targets with Linux kernels 2.5.46 and later,
335 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
336 fork and exec catchpoints.
338 * Remote syscall events
340 ** GDB now has support for catch syscall on remote Linux targets,
341 currently enabled on x86/x86_64 architectures.
343 set remote catch-syscall-packet
344 show remote catch-syscall-packet
345 Set/show the use of the remote catch syscall feature.
349 ** The -var-set-format command now accepts the zero-hexadecimal
350 format. It outputs data in hexadecimal format with zero-padding on the
355 ** gdb.InferiorThread objects have a new attribute "global_num",
356 which refers to the thread's global thread ID. The existing
357 "num" attribute now refers to the thread's per-inferior number.
358 See "Per-inferior thread numbers" above.
359 ** gdb.InferiorThread objects have a new attribute "inferior", which
360 is the Inferior object the thread belongs to.
362 *** Changes in GDB 7.10
364 * Support for process record-replay and reverse debugging on aarch64*-linux*
365 targets has been added. GDB now supports recording of A64 instruction set
366 including advance SIMD instructions.
368 * Support for Sun's version of the "stabs" debug file format has been removed.
370 * GDB now honors the content of the file /proc/PID/coredump_filter
371 (PID is the process ID) on GNU/Linux systems. This file can be used
372 to specify the types of memory mappings that will be included in a
373 corefile. For more information, please refer to the manual page of
374 "core(5)". GDB also has a new command: "set use-coredump-filter
375 on|off". It allows to set whether GDB will read the content of the
376 /proc/PID/coredump_filter file when generating a corefile.
378 * The "info os" command on GNU/Linux can now display information on
380 "info os cpus" Listing of all cpus/cores on the system
382 * GDB has two new commands: "set serial parity odd|even|none" and
383 "show serial parity". These allows to set or show parity for the
386 * The "info source" command now displays the producer string if it was
387 present in the debug info. This typically includes the compiler version
388 and may include things like its command line arguments.
390 * The "info dll", an alias of the "info sharedlibrary" command,
391 is now available on all platforms.
393 * Directory names supplied to the "set sysroot" commands may be
394 prefixed with "target:" to tell GDB to access shared libraries from
395 the target system, be it local or remote. This replaces the prefix
396 "remote:". The default sysroot has been changed from "" to
397 "target:". "remote:" is automatically converted to "target:" for
398 backward compatibility.
400 * The system root specified by "set sysroot" will be prepended to the
401 filename of the main executable (if reported to GDB as absolute by
402 the operating system) when starting processes remotely, and when
403 attaching to already-running local or remote processes.
405 * GDB now supports automatic location and retrieval of executable
406 files from remote targets. Remote debugging can now be initiated
407 using only a "target remote" or "target extended-remote" command
408 (no "set sysroot" or "file" commands are required). See "New remote
411 * The "dump" command now supports verilog hex format.
413 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
415 * On GNU/Linux, GDB and gdbserver are now able to access executable
416 and shared library files without a "set sysroot" command when
417 attaching to processes running in different mount namespaces from
418 the debugger. This makes it possible to attach to processes in
419 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
420 See "New remote packets" below.
422 * The "tui reg" command now provides completion for all of the
423 available register groups, including target specific groups.
425 * The HISTSIZE environment variable is no longer read when determining
426 the size of GDB's command history. GDB now instead reads the dedicated
427 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
428 disables truncation of command history. Non-numeric values of GDBHISTSIZE
433 ** Memory ports can now be unbuffered.
437 ** gdb.Objfile objects have a new attribute "username",
438 which is the name of the objfile as specified by the user,
439 without, for example, resolving symlinks.
440 ** You can now write frame unwinders in Python.
441 ** gdb.Type objects have a new method "optimized_out",
442 returning optimized out gdb.Value instance of this type.
443 ** gdb.Value objects have new methods "reference_value" and
444 "const_value" which return a reference to the value and a
445 "const" version of the value respectively.
449 maint print symbol-cache
450 Print the contents of the symbol cache.
452 maint print symbol-cache-statistics
453 Print statistics of symbol cache usage.
455 maint flush-symbol-cache
456 Flush the contents of the symbol cache.
460 Start branch trace recording using Branch Trace Store (BTS) format.
463 Evaluate expression by using the compiler and print result.
467 Explicit commands for enabling and disabling tui mode.
470 set mpx bound on i386 and amd64
471 Support for bound table investigation on Intel MPX enabled applications.
475 Start branch trace recording using Intel Processor Trace format.
478 Print information about branch tracing internals.
480 maint btrace packet-history
481 Print the raw branch tracing data.
483 maint btrace clear-packet-history
484 Discard the stored raw branch tracing data.
487 Discard all branch tracing data. It will be fetched and processed
488 anew by the next "record" command.
493 Renamed from "set debug dwarf2-die".
495 Renamed from "show debug dwarf2-die".
498 Renamed from "set debug dwarf2-read".
499 show debug dwarf-read
500 Renamed from "show debug dwarf2-read".
502 maint set dwarf always-disassemble
503 Renamed from "maint set dwarf2 always-disassemble".
504 maint show dwarf always-disassemble
505 Renamed from "maint show dwarf2 always-disassemble".
507 maint set dwarf max-cache-age
508 Renamed from "maint set dwarf2 max-cache-age".
509 maint show dwarf max-cache-age
510 Renamed from "maint show dwarf2 max-cache-age".
513 show debug dwarf-line
514 Control display of debugging info regarding DWARF line processing.
518 Set the maximum number of candidates to be considered during
519 completion. The default value is 200. This limit allows GDB
520 to avoid generating large completion lists, the computation of
521 which can cause the debugger to become temporarily unresponsive.
523 set history remove-duplicates
524 show history remove-duplicates
525 Control the removal of duplicate history entries.
527 maint set symbol-cache-size
528 maint show symbol-cache-size
529 Control the size of the symbol cache.
531 set|show record btrace bts buffer-size
532 Set and show the size of the ring buffer used for branch tracing in
534 The obtained size may differ from the requested size. Use "info
535 record" to see the obtained buffer size.
537 set debug linux-namespaces
538 show debug linux-namespaces
539 Control display of debugging info regarding Linux namespaces.
541 set|show record btrace pt buffer-size
542 Set and show the size of the ring buffer used for branch tracing in
543 Intel Processor Trace format.
544 The obtained size may differ from the requested size. Use "info
545 record" to see the obtained buffer size.
547 maint set|show btrace pt skip-pad
548 Set and show whether PAD packets are skipped when computing the
551 * The command 'thread apply all' can now support new option '-ascending'
552 to call its specified command for all threads in ascending order.
554 * Python/Guile scripting
556 ** GDB now supports auto-loading of Python/Guile scripts contained in the
557 special section named `.debug_gdb_scripts'.
561 qXfer:btrace-conf:read
562 Return the branch trace configuration for the current thread.
564 Qbtrace-conf:bts:size
565 Set the requested ring buffer size for branch tracing in BTS format.
568 Enable Intel Procesor Trace-based branch tracing for the current
569 process. The remote stub reports support for this packet to GDB's
573 Set the requested ring buffer size for branch tracing in Intel Processor
577 Indicates a memory breakpoint instruction was executed, irrespective
578 of whether it was GDB that planted the breakpoint or the breakpoint
579 is hardcoded in the program. This is required for correct non-stop
583 Indicates the target stopped for a hardware breakpoint. This is
584 required for correct non-stop mode operation.
587 Return information about files on the remote system.
590 Return the full absolute name of the file that was executed to
591 create a process running on the remote system.
594 Select the filesystem on which vFile: operations with filename
595 arguments will operate. This is required for GDB to be able to
596 access files on remote targets where the remote stub does not
597 share a common filesystem with the inferior(s).
600 Indicates that a fork system call was executed.
603 Indicates that a vfork system call was executed.
605 vforkdone stop reason
606 Indicates that a vfork child of the specified process has executed
607 an exec or exit, allowing the vfork parent to resume execution.
609 fork-events and vfork-events features in qSupported
610 The qSupported packet allows GDB to request support for fork and
611 vfork events using new 'gdbfeatures' fork-events and vfork-events,
612 and the qSupported response can contain the corresponding
613 'stubfeatures'. Set and show commands can be used to display
614 whether these features are enabled.
616 * Extended-remote fork events
618 ** GDB now has support for fork events on extended-remote Linux
619 targets. For targets with Linux kernels 2.5.60 and later, this
620 enables follow-fork-mode and detach-on-fork for both fork and
621 vfork, as well as fork and vfork catchpoints.
623 * The info record command now shows the recording format and the
624 branch tracing configuration for the current thread when using
625 the btrace record target.
626 For the BTS format, it shows the ring buffer size.
628 * GDB now has support for DTrace USDT (Userland Static Defined
629 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
631 * GDB now supports access to vector registers on S/390 GNU/Linux
634 * Removed command line options
636 -xdb HP-UX XDB compatibility mode.
638 * Removed targets and native configurations
640 HP/PA running HP-UX hppa*-*-hpux*
641 Itanium running HP-UX ia64-*-hpux*
643 * New configure options
646 This configure option allows the user to build GDB with support for
647 Intel Processor Trace (default: auto). This requires libipt.
649 --with-libipt-prefix=PATH
650 Specify the path to the version of libipt that GDB should use.
651 $PATH/include should contain the intel-pt.h header and
652 $PATH/lib should contain the libipt.so library.
654 *** Changes in GDB 7.9.1
658 ** Xmethods can now specify a result type.
660 *** Changes in GDB 7.9
662 * GDB now supports hardware watchpoints on x86 GNU Hurd.
666 ** You can now access frame registers from Python scripts.
667 ** New attribute 'producer' for gdb.Symtab objects.
668 ** gdb.Objfile objects have a new attribute "progspace",
669 which is the gdb.Progspace object of the containing program space.
670 ** gdb.Objfile objects have a new attribute "owner".
671 ** gdb.Objfile objects have a new attribute "build_id",
672 which is the build ID generated when the file was built.
673 ** gdb.Objfile objects have a new method "add_separate_debug_file".
674 ** A new event "gdb.clear_objfiles" has been added, triggered when
675 selecting a new file to debug.
676 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
677 ** New function gdb.lookup_objfile.
679 New events which are triggered when GDB modifies the state of the
682 ** gdb.events.inferior_call_pre: Function call is about to be made.
683 ** gdb.events.inferior_call_post: Function call has just been made.
684 ** gdb.events.memory_changed: A memory location has been altered.
685 ** gdb.events.register_changed: A register has been altered.
687 * New Python-based convenience functions:
689 ** $_caller_is(name [, number_of_frames])
690 ** $_caller_matches(regexp [, number_of_frames])
691 ** $_any_caller_is(name [, number_of_frames])
692 ** $_any_caller_matches(regexp [, number_of_frames])
694 * GDB now supports the compilation and injection of source code into
695 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
696 to compile the source code to object code, and if successful, inject
697 and execute that code within the current context of the inferior.
698 Currently the C language is supported. The commands used to
699 interface with this new feature are:
701 compile code [-raw|-r] [--] [source code]
702 compile file [-raw|-r] filename
706 demangle [-l language] [--] name
707 Demangle "name" in the specified language, or the current language
708 if elided. This command is renamed from the "maint demangle" command.
709 The latter is kept as a no-op to avoid "maint demangle" being interpreted
710 as "maint demangler-warning".
712 queue-signal signal-name-or-number
713 Queue a signal to be delivered to the thread when it is resumed.
715 add-auto-load-scripts-directory directory
716 Add entries to the list of directories from which to load auto-loaded
719 maint print user-registers
720 List all currently available "user" registers.
722 compile code [-r|-raw] [--] [source code]
723 Compile, inject, and execute in the inferior the executable object
724 code produced by compiling the provided source code.
726 compile file [-r|-raw] filename
727 Compile and inject into the inferior the executable object code
728 produced by compiling the source code stored in the filename
731 * On resume, GDB now always passes the signal the program had stopped
732 for to the thread the signal was sent to, even if the user changed
733 threads before resuming. Previously GDB would often (but not
734 always) deliver the signal to the thread that happens to be current
737 * Conversely, the "signal" command now consistently delivers the
738 requested signal to the current thread. GDB now asks for
739 confirmation if the program had stopped for a signal and the user
740 switched threads meanwhile.
742 * "breakpoint always-inserted" modes "off" and "auto" merged.
744 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
745 won't remove breakpoints from the target until all threads stop,
746 even in non-stop mode. The "auto" mode has been removed, and "off"
747 is now the default mode.
751 set debug symbol-lookup
752 show debug symbol-lookup
753 Control display of debugging info regarding symbol lookup.
757 ** The -list-thread-groups command outputs an exit-code field for
758 inferiors that have exited.
762 MIPS SDE mips*-sde*-elf*
766 Support for these obsolete configurations has been removed.
768 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
769 SGI Irix-5.x mips-*-irix5*
770 SGI Irix-6.x mips-*-irix6*
771 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
772 VAX running Ultrix vax-*-ultrix*
774 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
775 and "assf"), have been removed. Use the "sharedlibrary" command, or
776 its alias "share", instead.
778 *** Changes in GDB 7.8
780 * New command line options
783 This is an alias for the --data-directory option.
785 * GDB supports printing and modifying of variable length automatic arrays
786 as specified in ISO C99.
788 * The ARM simulator now supports instruction level tracing
789 with or without disassembly.
793 GDB now has support for scripting using Guile. Whether this is
794 available is determined at configure time.
795 Guile version 2.0 or greater is required.
796 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
798 * New commands (for set/show, see "New options" below)
802 Invoke CODE by passing it to the Guile interpreter.
806 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
808 info auto-load guile-scripts [regexp]
809 Print the list of automatically loaded Guile scripts.
811 * The source command is now capable of sourcing Guile scripts.
812 This feature is dependent on the debugger being built with Guile support.
816 set print symbol-loading (off|brief|full)
817 show print symbol-loading
818 Control whether to print informational messages when loading symbol
819 information for a file. The default is "full", but when debugging
820 programs with large numbers of shared libraries the amount of output
823 set guile print-stack (none|message|full)
824 show guile print-stack
825 Show a stack trace when an error is encountered in a Guile script.
827 set auto-load guile-scripts (on|off)
828 show auto-load guile-scripts
829 Control auto-loading of Guile script files.
831 maint ada set ignore-descriptive-types (on|off)
832 maint ada show ignore-descriptive-types
833 Control whether the debugger should ignore descriptive types in Ada
834 programs. The default is not to ignore the descriptive types. See
835 the user manual for more details on descriptive types and the intended
836 usage of this option.
838 set auto-connect-native-target
840 Control whether GDB is allowed to automatically connect to the
841 native target for the run, attach, etc. commands when not connected
842 to any target yet. See also "target native" below.
844 set record btrace replay-memory-access (read-only|read-write)
845 show record btrace replay-memory-access
846 Control what memory accesses are allowed during replay.
848 maint set target-async (on|off)
849 maint show target-async
850 This controls whether GDB targets operate in synchronous or
851 asynchronous mode. Normally the default is asynchronous, if it is
852 available; but this can be changed to more easily debug problems
853 occurring only in synchronous mode.
855 set mi-async (on|off)
857 Control whether MI asynchronous mode is preferred. This supersedes
858 "set target-async" of previous GDB versions.
860 * "set target-async" is deprecated as a CLI option and is now an alias
861 for "set mi-async" (only puts MI into async mode).
863 * Background execution commands (e.g., "c&", "s&", etc.) are now
864 possible ``out of the box'' if the target supports them. Previously
865 the user would need to explicitly enable the possibility with the
866 "set target-async on" command.
868 * New features in the GDB remote stub, GDBserver
870 ** New option --debug-format=option1[,option2,...] allows one to add
871 additional text to each output. At present only timestamps
872 are supported: --debug-format=timestamps.
873 Timestamps can also be turned on with the
874 "monitor set debug-format timestamps" command from GDB.
876 * The 'record instruction-history' command now starts counting instructions
877 at one. This also affects the instruction ranges reported by the
878 'record function-call-history' command when given the /i modifier.
880 * The command 'record function-call-history' supports a new modifier '/c' to
881 indent the function names based on their call stack depth.
882 The fields for the '/i' and '/l' modifier have been reordered.
883 The source line range is now prefixed with 'at'.
884 The instruction range is now prefixed with 'inst'.
885 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
886 "record instruction-history" and "list" commands.
888 * The ranges given as arguments to the 'record function-call-history' and
889 'record instruction-history' commands are now inclusive.
891 * The btrace record target now supports the 'record goto' command.
892 For locations inside the execution trace, the back trace is computed
893 based on the information stored in the execution trace.
895 * The btrace record target supports limited reverse execution and replay.
896 The target does not record data and therefore does not allow reading
899 * The "catch syscall" command now works on s390*-linux* targets.
901 * The "compare-sections" command is no longer specific to target
902 remote. It now works with all targets.
904 * All native targets are now consistently called "native".
905 Consequently, the "target child", "target GNU", "target djgpp",
906 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
907 commands have been replaced with "target native". The QNX/NTO port
908 leaves the "procfs" target in place and adds a "native" target for
909 consistency with other ports. The impact on users should be minimal
910 as these commands previously either throwed an error, or were
911 no-ops. The target's name is visible in the output of the following
912 commands: "help target", "info target", "info files", "maint print
915 * The "target native" command now connects to the native target. This
916 can be used to launch native programs even when "set
917 auto-connect-native-target" is set to off.
919 * GDB now supports access to Intel MPX registers on GNU/Linux.
921 * Support for Intel AVX-512 registers on GNU/Linux.
922 Support displaying and modifying Intel AVX-512 registers
923 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
927 qXfer:btrace:read's annex
928 The qXfer:btrace:read packet supports a new annex 'delta' to read
929 branch trace incrementally.
933 ** Valid Python operations on gdb.Value objects representing
934 structs/classes invoke the corresponding overloaded operators if
936 ** New `Xmethods' feature in the Python API. Xmethods are
937 additional methods or replacements for existing methods of a C++
938 class. This feature is useful for those cases where a method
939 defined in C++ source code could be inlined or optimized out by
940 the compiler, making it unavailable to GDB.
943 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
945 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
946 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
947 its alias "share", instead.
949 * The commands "set remotebaud" and "show remotebaud" are no longer
950 supported. Use "set serial baud" and "show serial baud" (respectively)
955 ** A new option "-gdb-set mi-async" replaces "-gdb-set
956 target-async". The latter is left as a deprecated alias of the
957 former for backward compatibility. If the target supports it,
958 CLI background execution commands are now always possible by
959 default, independently of whether the frontend stated a
960 preference for asynchronous execution with "-gdb-set mi-async".
961 Previously "-gdb-set target-async off" affected both MI execution
962 commands and CLI execution commands.
964 *** Changes in GDB 7.7
966 * Improved support for process record-replay and reverse debugging on
967 arm*-linux* targets. Support for thumb32 and syscall instruction
968 recording has been added.
970 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
972 * GDB now supports Fission DWP file format version 2.
973 http://gcc.gnu.org/wiki/DebugFission
975 * New convenience function "$_isvoid", to check whether an expression
976 is void. A void expression is an expression where the type of the
977 result is "void". For example, some convenience variables may be
978 "void" when evaluated (e.g., "$_exitcode" before the execution of
979 the program being debugged; or an undefined convenience variable).
980 Another example, when calling a function whose return type is
983 * The "maintenance print objfiles" command now takes an optional regexp.
985 * The "catch syscall" command now works on arm*-linux* targets.
987 * GDB now consistently shows "<not saved>" when printing values of
988 registers the debug info indicates have not been saved in the frame
989 and there's nowhere to retrieve them from
990 (callee-saved/call-clobbered registers):
995 (gdb) info registers rax
998 Before, the former would print "<optimized out>", and the latter
999 "*value not available*".
1001 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1006 ** Frame filters and frame decorators have been added.
1007 ** Temporary breakpoints are now supported.
1008 ** Line tables representation has been added.
1009 ** New attribute 'parent_type' for gdb.Field objects.
1010 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1011 ** New attribute 'name' for gdb.Type objects.
1015 Nios II ELF nios2*-*-elf
1016 Nios II GNU/Linux nios2*-*-linux
1017 Texas Instruments MSP430 msp430*-*-elf
1019 * Removed native configurations
1021 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1022 been removed. ELF variants of these configurations are kept supported.
1024 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1025 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1026 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1027 i[34567]86-*-openbsd3.[0-3]
1028 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1029 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1030 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1034 Like "catch throw", but catches a re-thrown exception.
1035 maint check-psymtabs
1036 Renamed from old "maint check-symtabs".
1038 Perform consistency checks on symtabs.
1039 maint expand-symtabs
1040 Expand symtabs matching an optional regexp.
1043 Display the details of GDB configure-time options.
1045 maint set|show per-command
1046 maint set|show per-command space
1047 maint set|show per-command time
1048 maint set|show per-command symtab
1049 Enable display of per-command gdb resource usage.
1051 remove-symbol-file FILENAME
1052 remove-symbol-file -a ADDRESS
1053 Remove a symbol file added via add-symbol-file. The file to remove
1054 can be identified by its filename or by an address that lies within
1055 the boundaries of this symbol file in memory.
1058 info exceptions REGEXP
1059 Display the list of Ada exceptions defined in the program being
1060 debugged. If provided, only the exceptions whose names match REGEXP
1065 set debug symfile off|on
1067 Control display of debugging info regarding reading symbol files and
1068 symbol tables within those files
1070 set print raw frame-arguments
1071 show print raw frame-arguments
1072 Set/show whether to print frame arguments in raw mode,
1073 disregarding any defined pretty-printers.
1075 set remote trace-status-packet
1076 show remote trace-status-packet
1077 Set/show the use of remote protocol qTStatus packet.
1081 Control display of debugging messages related to Nios II targets.
1085 Control whether target-assisted range stepping is enabled.
1087 set startup-with-shell
1088 show startup-with-shell
1089 Specifies whether Unix child processes are started via a shell or
1094 Use the target memory cache for accesses to the code segment. This
1095 improves performance of remote debugging (particularly disassembly).
1097 * You can now use a literal value 'unlimited' for options that
1098 interpret 0 or -1 as meaning "unlimited". E.g., "set
1099 trace-buffer-size unlimited" is now an alias for "set
1100 trace-buffer-size -1" and "set height unlimited" is now an alias for
1103 * The "set debug symtab-create" debugging option of GDB has been changed to
1104 accept a verbosity level. 0 means "off", 1 provides basic debugging
1105 output, and values of 2 or greater provides more verbose output.
1107 * New command-line options
1109 Display the details of GDB configure-time options.
1111 * The command 'tsave' can now support new option '-ctf' to save trace
1112 buffer in Common Trace Format.
1114 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1117 * GDB now implements the the C++ 'typeid' operator.
1119 * The new convenience variable $_exception holds the exception being
1120 thrown or caught at an exception-related catchpoint.
1122 * The exception-related catchpoints, like "catch throw", now accept a
1123 regular expression which can be used to filter exceptions by type.
1125 * The new convenience variable $_exitsignal is automatically set to
1126 the terminating signal number when the program being debugged dies
1127 due to an uncaught signal.
1131 ** All MI commands now accept an optional "--language" option.
1132 Support for this feature can be verified by using the "-list-features"
1133 command, which should contain "language-option".
1135 ** The new command -info-gdb-mi-command allows the user to determine
1136 whether a GDB/MI command is supported or not.
1138 ** The "^error" result record returned when trying to execute an undefined
1139 GDB/MI command now provides a variable named "code" whose content is the
1140 "undefined-command" error code. Support for this feature can be verified
1141 by using the "-list-features" command, which should contain
1142 "undefined-command-error-code".
1144 ** The -trace-save MI command can optionally save trace buffer in Common
1147 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1149 ** The command -data-list-register-values now accepts an optional
1150 "--skip-unavailable" option. When used, only the available registers
1153 ** The new command -trace-frame-collected dumps collected variables,
1154 computed expressions, tvars, memory and registers in a traceframe.
1156 ** The commands -stack-list-locals, -stack-list-arguments and
1157 -stack-list-variables now accept an option "--skip-unavailable".
1158 When used, only the available locals or arguments are displayed.
1160 ** The -exec-run command now accepts an optional "--start" option.
1161 When used, the command follows the same semantics as the "start"
1162 command, stopping the program's execution at the start of its
1163 main subprogram. Support for this feature can be verified using
1164 the "-list-features" command, which should contain
1165 "exec-run-start-option".
1167 ** The new commands -catch-assert and -catch-exceptions insert
1168 catchpoints stopping the program when Ada exceptions are raised.
1170 ** The new command -info-ada-exceptions provides the equivalent of
1171 the new "info exceptions" command.
1173 * New system-wide configuration scripts
1174 A GDB installation now provides scripts suitable for use as system-wide
1175 configuration scripts for the following systems:
1179 * GDB now supports target-assigned range stepping with remote targets.
1180 This improves the performance of stepping source lines by reducing
1181 the number of control packets from/to GDB. See "New remote packets"
1184 * GDB now understands the element 'tvar' in the XML traceframe info.
1185 It has the id of the collected trace state variables.
1187 * On S/390 targets that provide the transactional-execution feature,
1188 the program interruption transaction diagnostic block (TDB) is now
1189 represented as a number of additional "registers" in GDB.
1191 * New remote packets
1195 The vCont packet supports a new 'r' action, that tells the remote
1196 stub to step through an address range itself, without GDB
1197 involvemement at each single-step.
1199 qXfer:libraries-svr4:read's annex
1200 The previously unused annex of the qXfer:libraries-svr4:read packet
1201 is now used to support passing an argument list. The remote stub
1202 reports support for this argument list to GDB's qSupported query.
1203 The defined arguments are "start" and "prev", used to reduce work
1204 necessary for library list updating, resulting in significant
1207 * New features in the GDB remote stub, GDBserver
1209 ** GDBserver now supports target-assisted range stepping. Currently
1210 enabled on x86/x86_64 GNU/Linux targets.
1212 ** GDBserver now adds element 'tvar' in the XML in the reply to
1213 'qXfer:traceframe-info:read'. It has the id of the collected
1214 trace state variables.
1216 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1219 * New 'z' formatter for printing and examining memory, this displays the
1220 value as hexadecimal zero padded on the left to the size of the type.
1222 * GDB can now use Windows x64 unwinding data.
1224 * The "set remotebaud" command has been replaced by "set serial baud".
1225 Similarly, "show remotebaud" has been replaced by "show serial baud".
1226 The "set remotebaud" and "show remotebaud" commands are still available
1227 to provide backward compatibility with older versions of GDB.
1229 *** Changes in GDB 7.6
1231 * Target record has been renamed to record-full.
1232 Record/replay is now enabled with the "record full" command.
1233 This also affects settings that are associated with full record/replay
1234 that have been moved from "set/show record" to "set/show record full":
1236 set|show record full insn-number-max
1237 set|show record full stop-at-limit
1238 set|show record full memory-query
1240 * A new record target "record-btrace" has been added. The new target
1241 uses hardware support to record the control-flow of a process. It
1242 does not support replaying the execution, but it implements the
1243 below new commands for investigating the recorded execution log.
1244 This new recording method can be enabled using:
1248 The "record-btrace" target is only available on Intel Atom processors
1249 and requires a Linux kernel 2.6.32 or later.
1251 * Two new commands have been added for record/replay to give information
1252 about the recorded execution without having to replay the execution.
1253 The commands are only supported by "record btrace".
1255 record instruction-history prints the execution history at
1256 instruction granularity
1258 record function-call-history prints the execution history at
1259 function granularity
1261 * New native configurations
1263 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1264 FreeBSD/powerpc powerpc*-*-freebsd
1265 x86_64/Cygwin x86_64-*-cygwin*
1266 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1270 ARM AArch64 aarch64*-*-elf
1271 ARM AArch64 GNU/Linux aarch64*-*-linux
1272 Lynx 178 PowerPC powerpc-*-lynx*178
1273 x86_64/Cygwin x86_64-*-cygwin*
1274 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1276 * If the configured location of system.gdbinit file (as given by the
1277 --with-system-gdbinit option at configure time) is in the
1278 data-directory (as specified by --with-gdb-datadir at configure
1279 time) or in one of its subdirectories, then GDB will look for the
1280 system-wide init file in the directory specified by the
1281 --data-directory command-line option.
1283 * New command line options:
1285 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1286 other initialization files, unlike -nx which disables all of them.
1288 * Removed command line options
1290 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1293 * The 'ptype' and 'whatis' commands now accept an argument to control
1296 * 'info proc' now works on some core files.
1300 ** Vectors can be created with gdb.Type.vector.
1302 ** Python's atexit.register now works in GDB.
1304 ** Types can be pretty-printed via a Python API.
1306 ** Python 3 is now supported (in addition to Python 2.4 or later)
1308 ** New class gdb.Architecture exposes GDB's internal representation
1309 of architecture in the Python API.
1311 ** New method Frame.architecture returns the gdb.Architecture object
1312 corresponding to the frame's architecture.
1314 * New Python-based convenience functions:
1316 ** $_memeq(buf1, buf2, length)
1317 ** $_streq(str1, str2)
1319 ** $_regex(str, regex)
1321 * The 'cd' command now defaults to using '~' (the home directory) if not
1324 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1325 default for GCC since November 2000.
1327 * The command 'forward-search' can now be abbreviated as 'fo'.
1329 * The command 'info tracepoints' can now display 'installed on target'
1330 or 'not installed on target' for each non-pending location of tracepoint.
1332 * New configure options
1334 --enable-libmcheck/--disable-libmcheck
1335 By default, development versions are built with -lmcheck on hosts
1336 that support it, in order to help track memory corruption issues.
1337 Release versions, on the other hand, are built without -lmcheck
1338 by default. The --enable-libmcheck/--disable-libmcheck configure
1339 options allow the user to override that default.
1340 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1341 This configure option allows the user to build GDB with
1342 libbabeltrace using which GDB can read Common Trace Format data.
1344 * New commands (for set/show, see "New options" below)
1347 Catch signals. This is similar to "handle", but allows commands and
1348 conditions to be attached.
1351 List the BFDs known to GDB.
1353 python-interactive [command]
1355 Start a Python interactive prompt, or evaluate the optional command
1356 and print the result of expressions.
1359 "py" is a new alias for "python".
1361 enable type-printer [name]...
1362 disable type-printer [name]...
1363 Enable or disable type printers.
1367 ** For the Renesas Super-H architecture, the "regs" command has been removed
1368 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1373 set print type methods (on|off)
1374 show print type methods
1375 Control whether method declarations are displayed by "ptype".
1376 The default is to show them.
1378 set print type typedefs (on|off)
1379 show print type typedefs
1380 Control whether typedef definitions are displayed by "ptype".
1381 The default is to show them.
1383 set filename-display basename|relative|absolute
1384 show filename-display
1385 Control the way in which filenames is displayed.
1386 The default is "relative", which preserves previous behavior.
1388 set trace-buffer-size
1389 show trace-buffer-size
1390 Request target to change the size of trace buffer.
1392 set remote trace-buffer-size-packet auto|on|off
1393 show remote trace-buffer-size-packet
1394 Control the use of the remote protocol `QTBuffer:size' packet.
1398 Control display of debugging messages related to ARM AArch64.
1401 set debug coff-pe-read
1402 show debug coff-pe-read
1403 Control display of debugging messages related to reading of COFF/PE
1408 Control display of debugging messages related to Mach-O symbols
1411 set debug notification
1412 show debug notification
1413 Control display of debugging info for async remote notification.
1417 ** Command parameter changes are now notified using new async record
1418 "=cmd-param-changed".
1419 ** Trace frame changes caused by command "tfind" are now notified using
1420 new async record "=traceframe-changed".
1421 ** The creation, deletion and modification of trace state variables
1422 are now notified using new async records "=tsv-created",
1423 "=tsv-deleted" and "=tsv-modified".
1424 ** The start and stop of process record are now notified using new
1425 async record "=record-started" and "=record-stopped".
1426 ** Memory changes are now notified using new async record
1428 ** The data-disassemble command response will include a "fullname" field
1429 containing the absolute file name when source has been requested.
1430 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1431 command, to allow pattern filling of memory areas.
1432 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1433 library load/unload events.
1434 ** The response to breakpoint commands and breakpoint async records
1435 includes an "installed" field containing a boolean state about each
1436 non-pending tracepoint location is whether installed on target or not.
1437 ** Output of the "-trace-status" command includes a "trace-file" field
1438 containing the name of the trace file being examined. This field is
1439 optional, and only present when examining a trace file.
1440 ** The "fullname" field is now always present along with the "file" field,
1441 even if the file cannot be found by GDB.
1443 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1444 You must have the LZMA library available when configuring GDB for this
1445 feature to be enabled. For more information, see:
1446 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1448 * New remote packets
1451 Set the size of trace buffer. The remote stub reports support for this
1452 packet to gdb's qSupported query.
1455 Enable Branch Trace Store (BTS)-based branch tracing for the current
1456 thread. The remote stub reports support for this packet to gdb's
1460 Disable branch tracing for the current thread. The remote stub reports
1461 support for this packet to gdb's qSupported query.
1464 Read the traced branches for the current thread. The remote stub
1465 reports support for this packet to gdb's qSupported query.
1467 *** Changes in GDB 7.5
1469 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1470 for more x32 ABI info.
1472 * GDB now supports access to MIPS DSP registers on Linux targets.
1474 * GDB now supports debugging microMIPS binaries.
1476 * The "info os" command on GNU/Linux can now display information on
1477 several new classes of objects managed by the operating system:
1478 "info os procgroups" lists process groups
1479 "info os files" lists file descriptors
1480 "info os sockets" lists internet-domain sockets
1481 "info os shm" lists shared-memory regions
1482 "info os semaphores" lists semaphores
1483 "info os msg" lists message queues
1484 "info os modules" lists loaded kernel modules
1486 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1487 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1488 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1489 options and inspect the probe arguments using the new $_probe_arg family
1490 of convenience variables. You can obtain more information about SystemTap
1491 in <http://sourceware.org/systemtap/>.
1493 * GDB now supports reversible debugging on ARM, it allows you to
1494 debug basic ARM and THUMB instructions, and provides
1495 record/replay support.
1497 * The option "symbol-reloading" has been deleted as it is no longer used.
1501 ** GDB commands implemented in Python can now be put in command class
1504 ** The "maint set python print-stack on|off" is now deleted.
1506 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1507 apply "flag enum"-style pretty-printing to any enum.
1509 ** gdb.lookup_symbol can now work when there is no current frame.
1511 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1512 the source at which the symbol was defined.
1514 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1515 method 'value'. The former indicates whether the symbol needs a
1516 frame in order to compute its value, and the latter computes the
1519 ** A new method 'referenced_value' on gdb.Value objects which can
1520 dereference pointer as well as C++ reference values.
1522 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1523 which return the global and static blocks (as gdb.Block objects),
1524 of the underlying symbol table, respectively.
1526 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1527 object associated with a PC value.
1529 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1530 of the address range occupied by code for the current source line.
1532 * Go language support.
1533 GDB now supports debugging programs written in the Go programming
1536 * GDBserver now supports stdio connections.
1537 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1539 * The binary "gdbtui" can no longer be built or installed.
1540 Use "gdb -tui" instead.
1542 * GDB will now print "flag" enums specially. A flag enum is one where
1543 all the enumerator values have no bits in common when pairwise
1544 "and"ed. When printing a value whose type is a flag enum, GDB will
1545 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1546 (gdb) print (enum E) 3
1549 * The filename part of a linespec will now match trailing components
1550 of a source file name. For example, "break gcc/expr.c:1000" will
1551 now set a breakpoint in build/gcc/expr.c, but not
1552 build/libcpp/expr.c.
1554 * The "info proc" and "generate-core-file" commands will now also
1555 work on remote targets connected to GDBserver on Linux.
1557 * The command "info catch" has been removed. It has been disabled
1558 since December 2007.
1560 * The "catch exception" and "catch assert" commands now accept
1561 a condition at the end of the command, much like the "break"
1562 command does. For instance:
1564 (gdb) catch exception Constraint_Error if Barrier = True
1566 Previously, it was possible to add a condition to such catchpoints,
1567 but it had to be done as a second step, after the catchpoint had been
1568 created, using the "condition" command.
1570 * The "info static-tracepoint-marker" command will now also work on
1571 native Linux targets with in-process agent.
1573 * GDB can now set breakpoints on inlined functions.
1575 * The .gdb_index section has been updated to include symbols for
1576 inlined functions. GDB will ignore older .gdb_index sections by
1577 default, which could cause symbol files to be loaded more slowly
1578 until their .gdb_index sections can be recreated. The new command
1579 "set use-deprecated-index-sections on" will cause GDB to use any older
1580 .gdb_index sections it finds. This will restore performance, but the
1581 ability to set breakpoints on inlined functions will be lost in symbol
1582 files with older .gdb_index sections.
1584 The .gdb_index section has also been updated to record more information
1585 about each symbol. This speeds up the "info variables", "info functions"
1586 and "info types" commands when used with programs having the .gdb_index
1587 section, as well as speeding up debugging with shared libraries using
1588 the .gdb_index section.
1590 * Ada support for GDB/MI Variable Objects has been added.
1592 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1597 ** New command -info-os is the MI equivalent of "info os".
1599 ** Output logs ("set logging" and related) now include MI output.
1603 ** "set use-deprecated-index-sections on|off"
1604 "show use-deprecated-index-sections on|off"
1605 Controls the use of deprecated .gdb_index sections.
1607 ** "catch load" and "catch unload" can be used to stop when a shared
1608 library is loaded or unloaded, respectively.
1610 ** "enable count" can be used to auto-disable a breakpoint after
1613 ** "info vtbl" can be used to show the virtual method tables for
1614 C++ and Java objects.
1616 ** "explore" and its sub commands "explore value" and "explore type"
1617 can be used to recursively explore values and types of
1618 expressions. These commands are available only if GDB is
1619 configured with '--with-python'.
1621 ** "info auto-load" shows status of all kinds of auto-loaded files,
1622 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1623 sequences of commands files, "info auto-load python-scripts"
1624 shows status of auto-loading Python script files,
1625 "info auto-load local-gdbinit" shows status of loading init file
1626 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1627 status of inferior specific thread debugging shared library loading.
1629 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1630 and "show auto-load-scripts" commands have been deprecated, use their
1631 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1632 and "show auto-load python-scripts" counterparts instead.
1634 ** "dprintf location,format,args..." creates a dynamic printf, which
1635 is basically a breakpoint that does a printf and immediately
1636 resumes your program's execution, so it is like a printf that you
1637 can insert dynamically at runtime instead of at compiletime.
1639 ** "set print symbol"
1641 Controls whether GDB attempts to display the symbol, if any,
1642 corresponding to addresses it prints. This defaults to "on", but
1643 you can set it to "off" to restore GDB's previous behavior.
1645 * Deprecated commands
1647 ** For the Renesas Super-H architecture, the "regs" command has been
1648 deprecated, and "info all-registers" should be used instead.
1652 Renesas RL78 rl78-*-elf
1653 HP OpenVMS ia64 ia64-hp-openvms*
1655 * GDBserver supports evaluation of breakpoint conditions. When
1656 support is advertised by GDBserver, GDB may be told to send the
1657 breakpoint conditions in bytecode form to GDBserver. GDBserver
1658 will only report the breakpoint trigger to GDB when its condition
1663 set mips compression
1664 show mips compression
1665 Select the compressed ISA encoding used in functions that have no symbol
1666 information available. The encoding can be set to either of:
1669 and is updated automatically from ELF file flags if available.
1671 set breakpoint condition-evaluation
1672 show breakpoint condition-evaluation
1673 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1674 GDBserver ("target"). Default option "auto" chooses the most efficient
1676 This option can improve debugger efficiency depending on the speed of the
1680 Disable auto-loading globally.
1683 Show auto-loading setting of all kinds of auto-loaded files.
1685 set auto-load gdb-scripts on|off
1686 show auto-load gdb-scripts
1687 Control auto-loading of GDB canned sequences of commands files.
1689 set auto-load python-scripts on|off
1690 show auto-load python-scripts
1691 Control auto-loading of Python script files.
1693 set auto-load local-gdbinit on|off
1694 show auto-load local-gdbinit
1695 Control loading of init file (.gdbinit) from current directory.
1697 set auto-load libthread-db on|off
1698 show auto-load libthread-db
1699 Control auto-loading of inferior specific thread debugging shared library.
1701 set auto-load scripts-directory <dir1>[:<dir2>...]
1702 show auto-load scripts-directory
1703 Set a list of directories from which to load auto-loaded scripts.
1704 Automatically loaded Python scripts and GDB scripts are located in one
1705 of the directories listed by this option.
1706 The delimiter (':' above) may differ according to the host platform.
1708 set auto-load safe-path <dir1>[:<dir2>...]
1709 show auto-load safe-path
1710 Set a list of directories from which it is safe to auto-load files.
1711 The delimiter (':' above) may differ according to the host platform.
1713 set debug auto-load on|off
1714 show debug auto-load
1715 Control display of debugging info for auto-loading the files above.
1717 set dprintf-style gdb|call|agent
1719 Control the way in which a dynamic printf is performed; "gdb"
1720 requests a GDB printf command, while "call" causes dprintf to call a
1721 function in the inferior. "agent" requests that the target agent
1722 (such as GDBserver) do the printing.
1724 set dprintf-function <expr>
1725 show dprintf-function
1726 set dprintf-channel <expr>
1727 show dprintf-channel
1728 Set the function and optional first argument to the call when using
1729 the "call" style of dynamic printf.
1731 set disconnected-dprintf on|off
1732 show disconnected-dprintf
1733 Control whether agent-style dynamic printfs continue to be in effect
1734 after GDB disconnects.
1736 * New configure options
1738 --with-auto-load-dir
1739 Configure default value for the 'set auto-load scripts-directory'
1740 setting above. It defaults to '$debugdir:$datadir/auto-load',
1741 $debugdir representing global debugging info directories (available
1742 via 'show debug-file-directory') and $datadir representing GDB's data
1743 directory (available via 'show data-directory').
1745 --with-auto-load-safe-path
1746 Configure default value for the 'set auto-load safe-path' setting
1747 above. It defaults to the --with-auto-load-dir setting.
1749 --without-auto-load-safe-path
1750 Set 'set auto-load safe-path' to '/', effectively disabling this
1753 * New remote packets
1755 z0/z1 conditional breakpoints extension
1757 The z0/z1 breakpoint insertion packets have been extended to carry
1758 a list of conditional expressions over to the remote stub depending on the
1759 condition evaluation mode. The use of this extension can be controlled
1760 via the "set remote conditional-breakpoints-packet" command.
1764 Specify the signals which the remote stub may pass to the debugged
1765 program without GDB involvement.
1767 * New command line options
1769 --init-command=FILE, -ix Like --command, -x but execute it
1770 before loading inferior.
1771 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1772 execute it before loading inferior.
1774 *** Changes in GDB 7.4
1776 * GDB now handles ambiguous linespecs more consistently; the existing
1777 FILE:LINE support has been expanded to other types of linespecs. A
1778 breakpoint will now be set on all matching locations in all
1779 inferiors, and locations will be added or removed according to
1782 * GDB now allows you to skip uninteresting functions and files when
1783 stepping with the "skip function" and "skip file" commands.
1785 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1786 and "show remote hardware-watchpoint-length-limit". These allows to
1787 set or show the maximum length limit (in bytes) of a remote
1788 target hardware watchpoint.
1790 This allows e.g. to use "unlimited" hardware watchpoints with the
1791 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1792 watchpoints are slower than real hardware watchpoints but are
1793 significantly faster than gdb software watchpoints.
1797 ** The register_pretty_printer function in module gdb.printing now takes
1798 an optional `replace' argument. If True, the new printer replaces any
1801 ** The "maint set python print-stack on|off" command has been
1802 deprecated and will be deleted in GDB 7.5.
1803 A new command: "set python print-stack none|full|message" has
1804 replaced it. Additionally, the default for "print-stack" is
1805 now "message", which just prints the error message without
1808 ** A prompt substitution hook (prompt_hook) is now available to the
1811 ** A new Python module, gdb.prompt has been added to the GDB Python
1812 modules library. This module provides functionality for
1813 escape sequences in prompts (used by set/show
1814 extended-prompt). These escape sequences are replaced by their
1815 corresponding value.
1817 ** Python commands and convenience-functions located in
1818 'data-directory'/python/gdb/command and
1819 'data-directory'/python/gdb/function are now automatically loaded
1822 ** Blocks now provide four new attributes. global_block and
1823 static_block will return the global and static blocks
1824 respectively. is_static and is_global are boolean attributes
1825 that indicate if the block is one of those two types.
1827 ** Symbols now provide the "type" attribute, the type of the symbol.
1829 ** The "gdb.breakpoint" function has been deprecated in favor of
1832 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1833 of a function. This class is based on the "finish" command
1834 available in the CLI.
1836 ** Type objects for struct and union types now allow access to
1837 the fields using standard Python dictionary (mapping) methods.
1838 For example, "some_type['myfield']" now works, as does
1839 "some_type.items()".
1841 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1844 ** A new function, "deep_items" has been added to the gdb.types
1845 module in the GDB Python modules library. This function returns
1846 an iterator over the fields of a struct or union type. Unlike
1847 the standard Python "iteritems" method, it will recursively traverse
1848 any anonymous fields.
1852 ** "*stopped" events can report several new "reason"s, such as
1855 ** Breakpoint changes are now notified using new async records, like
1856 "=breakpoint-modified".
1858 ** New command -ada-task-info.
1860 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1861 $sdir specifies the default system locations of shared libraries.
1862 $pdir specifies the directory where the libpthread used by the application
1865 GDB no longer looks in $sdir and $pdir after it has searched the directories
1866 mentioned in libthread-db-search-path. If you want to search those
1867 directories, they must be specified in libthread-db-search-path.
1868 The default value of libthread-db-search-path on GNU/Linux and Solaris
1869 systems is now "$sdir:$pdir".
1871 $pdir is not supported by gdbserver, it is currently ignored.
1872 $sdir is supported by gdbserver.
1874 * New configure option --with-iconv-bin.
1875 When using the internationalization support like the one in the GNU C
1876 library, GDB will invoke the "iconv" program to get a list of supported
1877 character sets. If this program lives in a non-standard location, one can
1878 use this option to specify where to find it.
1880 * When natively debugging programs on PowerPC BookE processors running
1881 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1882 watchpoints, which specify a mask in addition to an address to watch.
1883 The mask specifies that some bits of an address (the bits which are
1884 reset in the mask) should be ignored when matching the address accessed
1885 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1886 section in the user manual for more details.
1888 * The new option --once causes GDBserver to stop listening for connections once
1889 the first connection is made. The listening port used by GDBserver will
1890 become available after that.
1892 * New commands "info macros" and "alias" have been added.
1894 * New function parameters suffix @entry specifies value of function parameter
1895 at the time the function got called. Entry values are available only since
1901 "!" is now an alias of the "shell" command.
1902 Note that no space is needed between "!" and SHELL COMMAND.
1906 watch EXPRESSION mask MASK_VALUE
1907 The watch command now supports the mask argument which allows creation
1908 of masked watchpoints, if the current architecture supports this feature.
1910 info auto-load-scripts [REGEXP]
1911 This command was formerly named "maintenance print section-scripts".
1912 It is now generally useful and is no longer a maintenance-only command.
1914 info macro [-all] [--] MACRO
1915 The info macro command has new options `-all' and `--'. The first for
1916 printing all definitions of a macro. The second for explicitly specifying
1917 the end of arguments and the beginning of the macro name in case the macro
1918 name starts with a hyphen.
1920 collect[/s] EXPRESSIONS
1921 The tracepoint collect command now takes an optional modifier "/s"
1922 that directs it to dereference pointer-to-character types and
1923 collect the bytes of memory up to a zero byte. The behavior is
1924 similar to what you see when you use the regular print command on a
1925 string. An optional integer following the "/s" sets a bound on the
1926 number of bytes that will be collected.
1929 The trace start command now interprets any supplied arguments as a
1930 note to be recorded with the trace run, with an effect similar to
1931 setting the variable trace-notes.
1934 The trace stop command now interprets any arguments as a note to be
1935 mentioned along with the tstatus report that the trace was stopped
1936 with a command. The effect is similar to setting the variable
1939 * Tracepoints can now be enabled and disabled at any time after a trace
1940 experiment has been started using the standard "enable" and "disable"
1941 commands. It is now possible to start a trace experiment with no enabled
1942 tracepoints; GDB will display a warning, but will allow the experiment to
1943 begin, assuming that tracepoints will be enabled as needed while the trace
1946 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1947 locations with 4-byte instructions, when they were previously
1948 limited to locations with instructions of 5 bytes or longer.
1952 set debug dwarf2-read
1953 show debug dwarf2-read
1954 Turns on or off display of debugging messages related to reading
1955 DWARF debug info. The default is off.
1957 set debug symtab-create
1958 show debug symtab-create
1959 Turns on or off display of debugging messages related to symbol table
1960 creation. The default is off.
1963 show extended-prompt
1964 Set the GDB prompt, and allow escape sequences to be inserted to
1965 display miscellaneous information (see 'help set extended-prompt'
1966 for the list of sequences). This prompt (and any information
1967 accessed through the escape sequences) is updated every time the
1968 prompt is displayed.
1970 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1971 show print entry-values
1972 Set printing of frame argument values at function entry. In some cases
1973 GDB can determine the value of function argument which was passed by the
1974 function caller, even if the value was modified inside the called function.
1976 set debug entry-values
1977 show debug entry-values
1978 Control display of debugging info for determining frame argument values at
1979 function entry and virtual tail call frames.
1981 set basenames-may-differ
1982 show basenames-may-differ
1983 Set whether a source file may have multiple base names.
1984 (A "base name" is the name of a file with the directory part removed.
1985 Example: The base name of "/home/user/hello.c" is "hello.c".)
1986 If set, GDB will canonicalize file names (e.g., expand symlinks)
1987 before comparing them. Canonicalization is an expensive operation,
1988 but it allows the same file be known by more than one base name.
1989 If not set (the default), all source files are assumed to have just
1990 one base name, and gdb will do file name comparisons more efficiently.
1996 Set a user name and notes for the current and any future trace runs.
1997 This is useful for long-running and/or disconnected traces, to
1998 inform others (or yourself) as to who is running the trace, supply
1999 contact information, or otherwise explain what is going on.
2001 set trace-stop-notes
2002 show trace-stop-notes
2003 Set a note attached to the trace run, that is displayed when the
2004 trace has been stopped by a tstop command. This is useful for
2005 instance as an explanation, if you are stopping a trace run that was
2006 started by someone else.
2008 * New remote packets
2012 Dynamically enable a tracepoint in a started trace experiment.
2016 Dynamically disable a tracepoint in a started trace experiment.
2020 Set the user and notes of the trace run.
2024 Query the current status of a tracepoint.
2028 Query the minimum length of instruction at which a fast tracepoint may
2031 * Dcache size (number of lines) and line-size are now runtime-configurable
2032 via "set dcache line" and "set dcache line-size" commands.
2036 Texas Instruments TMS320C6x tic6x-*-*
2040 Renesas RL78 rl78-*-elf
2042 *** Changes in GDB 7.3.1
2044 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2046 *** Changes in GDB 7.3
2048 * GDB has a new command: "thread find [REGEXP]".
2049 It finds the thread id whose name, target id, or thread extra info
2050 matches the given regular expression.
2052 * The "catch syscall" command now works on mips*-linux* targets.
2054 * The -data-disassemble MI command now supports modes 2 and 3 for
2055 dumping the instruction opcodes.
2057 * New command line options
2059 -data-directory DIR Specify DIR as the "data-directory".
2060 This is mostly for testing purposes.
2062 * The "maint set python auto-load on|off" command has been renamed to
2063 "set auto-load-scripts on|off".
2065 * GDB has a new command: "set directories".
2066 It is like the "dir" command except that it replaces the
2067 source path list instead of augmenting it.
2069 * GDB now understands thread names.
2071 On GNU/Linux, "info threads" will display the thread name as set by
2072 prctl or pthread_setname_np.
2074 There is also a new command, "thread name", which can be used to
2075 assign a name internally for GDB to display.
2078 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2079 has been integrated into GDB.
2083 ** The function gdb.Write now accepts an optional keyword 'stream'.
2084 This keyword, when provided, will direct the output to either
2085 stdout, stderr, or GDB's logging output.
2087 ** Parameters can now be be sub-classed in Python, and in particular
2088 you may implement the get_set_doc and get_show_doc functions.
2089 This improves how Parameter set/show documentation is processed
2090 and allows for more dynamic content.
2092 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2093 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2094 have an is_valid method.
2096 ** Breakpoints can now be sub-classed in Python, and in particular
2097 you may implement a 'stop' function that is executed each time
2098 the inferior reaches that breakpoint.
2100 ** New function gdb.lookup_global_symbol looks up a global symbol.
2102 ** GDB values in Python are now callable if the value represents a
2103 function. For example, if 'some_value' represents a function that
2104 takes two integer parameters and returns a value, you can call
2105 that function like so:
2107 result = some_value (10,20)
2109 ** Module gdb.types has been added.
2110 It contains a collection of utilities for working with gdb.Types objects:
2111 get_basic_type, has_field, make_enum_dict.
2113 ** Module gdb.printing has been added.
2114 It contains utilities for writing and registering pretty-printers.
2115 New classes: PrettyPrinter, SubPrettyPrinter,
2116 RegexpCollectionPrettyPrinter.
2117 New function: register_pretty_printer.
2119 ** New commands "info pretty-printers", "enable pretty-printer" and
2120 "disable pretty-printer" have been added.
2122 ** gdb.parameter("directories") is now available.
2124 ** New function gdb.newest_frame returns the newest frame in the
2127 ** The gdb.InferiorThread class has a new "name" attribute. This
2128 holds the thread's name.
2130 ** Python Support for Inferior events.
2131 Python scripts can add observers to be notified of events
2132 occurring in the process being debugged.
2133 The following events are currently supported:
2134 - gdb.events.cont Continue event.
2135 - gdb.events.exited Inferior exited event.
2136 - gdb.events.stop Signal received, and Breakpoint hit events.
2140 ** GDB now puts template parameters in scope when debugging in an
2141 instantiation. For example, if you have:
2143 template<int X> int func (void) { return X; }
2145 then if you step into func<5>, "print X" will show "5". This
2146 feature requires proper debuginfo support from the compiler; it
2147 was added to GCC 4.5.
2149 ** The motion commands "next", "finish", "until", and "advance" now
2150 work better when exceptions are thrown. In particular, GDB will
2151 no longer lose control of the inferior; instead, the GDB will
2152 stop the inferior at the point at which the exception is caught.
2153 This functionality requires a change in the exception handling
2154 code that was introduced in GCC 4.5.
2156 * GDB now follows GCC's rules on accessing volatile objects when
2157 reading or writing target state during expression evaluation.
2158 One notable difference to prior behavior is that "print x = 0"
2159 no longer generates a read of x; the value of the assignment is
2160 now always taken directly from the value being assigned.
2162 * GDB now has some support for using labels in the program's source in
2163 linespecs. For instance, you can use "advance label" to continue
2164 execution to a label.
2166 * GDB now has support for reading and writing a new .gdb_index
2167 section. This section holds a fast index of DWARF debugging
2168 information and can be used to greatly speed up GDB startup and
2169 operation. See the documentation for `save gdb-index' for details.
2171 * The "watch" command now accepts an optional "-location" argument.
2172 When used, this causes GDB to watch the memory referred to by the
2173 expression. Such a watchpoint is never deleted due to it going out
2176 * GDB now supports thread debugging of core dumps on GNU/Linux.
2178 GDB now activates thread debugging using the libthread_db library
2179 when debugging GNU/Linux core dumps, similarly to when debugging
2180 live processes. As a result, when debugging a core dump file, GDB
2181 is now able to display pthread_t ids of threads. For example, "info
2182 threads" shows the same output as when debugging the process when it
2183 was live. In earlier releases, you'd see something like this:
2186 * 1 LWP 6780 main () at main.c:10
2188 While now you see this:
2191 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2193 It is also now possible to inspect TLS variables when debugging core
2196 When debugging a core dump generated on a machine other than the one
2197 used to run GDB, you may need to point GDB at the correct
2198 libthread_db library with the "set libthread-db-search-path"
2199 command. See the user manual for more details on this command.
2201 * When natively debugging programs on PowerPC BookE processors running
2202 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2203 which stop execution of the inferior whenever it executes an instruction
2204 at any address within the specified range. See the "PowerPC Embedded"
2205 section in the user manual for more details.
2207 * New features in the GDB remote stub, GDBserver
2209 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2210 and i686 LynxOS (version 5.x).
2212 ** GDBserver is now supported on Blackfin Linux.
2214 * New native configurations
2216 ia64 HP-UX ia64-*-hpux*
2220 Analog Devices, Inc. Blackfin Processor bfin-*
2222 * Ada task switching is now supported on sparc-elf targets when
2223 debugging a program using the Ravenscar Profile. For more information,
2224 see the "Tasking Support when using the Ravenscar Profile" section
2225 in the GDB user manual.
2227 * Guile support was removed.
2229 * New features in the GNU simulator
2231 ** The --map-info flag lists all known core mappings.
2233 ** CFI flashes may be simulated via the "cfi" device.
2235 *** Changes in GDB 7.2
2237 * Shared library support for remote targets by default
2239 When GDB is configured for a generic, non-OS specific target, like
2240 for example, --target=arm-eabi or one of the many *-*-elf targets,
2241 GDB now queries remote stubs for loaded shared libraries using the
2242 `qXfer:libraries:read' packet. Previously, shared library support
2243 was always disabled for such configurations.
2247 ** Argument Dependent Lookup (ADL)
2249 In C++ ADL lookup directs function search to the namespaces of its
2250 arguments even if the namespace has not been imported.
2260 Here the compiler will search for `foo' in the namespace of 'b'
2261 and find A::foo. GDB now supports this. This construct is commonly
2262 used in the Standard Template Library for operators.
2264 ** Improved User Defined Operator Support
2266 In addition to member operators, GDB now supports lookup of operators
2267 defined in a namespace and imported with a `using' directive, operators
2268 defined in the global scope, operators imported implicitly from an
2269 anonymous namespace, and the ADL operators mentioned in the previous
2271 GDB now also supports proper overload resolution for all the previously
2272 mentioned flavors of operators.
2274 ** static const class members
2276 Printing of static const class members that are initialized in the
2277 class definition has been fixed.
2279 * Windows Thread Information Block access.
2281 On Windows targets, GDB now supports displaying the Windows Thread
2282 Information Block (TIB) structure. This structure is visible either
2283 by using the new command `info w32 thread-information-block' or, by
2284 dereferencing the new convenience variable named `$_tlb', a
2285 thread-specific pointer to the TIB. This feature is also supported
2286 when remote debugging using GDBserver.
2288 * Static tracepoints
2290 Static tracepoints are calls in the user program into a tracing
2291 library. One such library is a port of the LTTng kernel tracer to
2292 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2293 When debugging with GDBserver, GDB now supports combining the GDB
2294 tracepoint machinery with such libraries. For example: the user can
2295 use GDB to probe a static tracepoint marker (a call from the user
2296 program into the tracing library) with the new "strace" command (see
2297 "New commands" below). This creates a "static tracepoint" in the
2298 breakpoint list, that can be manipulated with the same feature set
2299 as fast and regular tracepoints. E.g., collect registers, local and
2300 global variables, collect trace state variables, and define
2301 tracepoint conditions. In addition, the user can collect extra
2302 static tracepoint marker specific data, by collecting the new
2303 $_sdata internal variable. When analyzing the trace buffer, you can
2304 inspect $_sdata like any other variable available to GDB. For more
2305 information, see the "Tracepoints" chapter in GDB user manual. New
2306 remote packets have been defined to support static tracepoints, see
2307 the "New remote packets" section below.
2309 * Better reconstruction of tracepoints after disconnected tracing
2311 GDB will attempt to download the original source form of tracepoint
2312 definitions when starting a trace run, and then will upload these
2313 upon reconnection to the target, resulting in a more accurate
2314 reconstruction of the tracepoints that are in use on the target.
2318 You can now exercise direct control over the ways that GDB can
2319 affect your program. For instance, you can disallow the setting of
2320 breakpoints, so that the program can run continuously (assuming
2321 non-stop mode). In addition, the "observer" variable is available
2322 to switch all of the different controls; in observer mode, GDB
2323 cannot affect the target's behavior at all, which is useful for
2324 tasks like diagnosing live systems in the field.
2326 * The new convenience variable $_thread holds the number of the
2329 * New remote packets
2333 Return the address of the Windows Thread Information Block of a given thread.
2337 In response to several of the tracepoint packets, the target may now
2338 also respond with a number of intermediate `qRelocInsn' request
2339 packets before the final result packet, to have GDB handle
2340 relocating an instruction to execute at a different address. This
2341 is particularly useful for stubs that support fast tracepoints. GDB
2342 reports support for this feature in the qSupported packet.
2346 List static tracepoint markers in the target program.
2350 List static tracepoint markers at a given address in the target
2353 qXfer:statictrace:read
2355 Read the static trace data collected (by a `collect $_sdata'
2356 tracepoint action). The remote stub reports support for this packet
2357 to gdb's qSupported query.
2361 Send the current settings of GDB's permission flags.
2365 Send part of the source (textual) form of a tracepoint definition,
2366 which includes location, conditional, and action list.
2368 * The source command now accepts a -s option to force searching for the
2369 script in the source search path even if the script name specifies
2372 * New features in the GDB remote stub, GDBserver
2374 - GDBserver now support tracepoints (including fast tracepoints, and
2375 static tracepoints). The feature is currently supported by the
2376 i386-linux and amd64-linux builds. See the "Tracepoints support
2377 in gdbserver" section in the manual for more information.
2379 GDBserver JIT compiles the tracepoint's conditional agent
2380 expression bytecode into native code whenever possible for low
2381 overhead dynamic tracepoints conditionals. For such tracepoints,
2382 an expression that examines program state is evaluated when the
2383 tracepoint is reached, in order to determine whether to capture
2384 trace data. If the condition is simple and false, processing the
2385 tracepoint finishes very quickly and no data is gathered.
2387 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2388 for static tracepoints support.
2390 - GDBserver now supports x86_64 Windows 64-bit debugging.
2392 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2393 it understands register description.
2395 * The --batch flag now disables pagination and queries.
2397 * X86 general purpose registers
2399 GDB now supports reading/writing byte, word and double-word x86
2400 general purpose registers directly. This means you can use, say,
2401 $ah or $ax to refer, respectively, to the byte register AH and
2402 16-bit word register AX that are actually portions of the 32-bit
2403 register EAX or 64-bit register RAX.
2405 * The `commands' command now accepts a range of breakpoints to modify.
2406 A plain `commands' following a command that creates multiple
2407 breakpoints affects all the breakpoints set by that command. This
2408 applies to breakpoints set by `rbreak', and also applies when a
2409 single `break' command creates multiple breakpoints (e.g.,
2410 breakpoints on overloaded c++ functions).
2412 * The `rbreak' command now accepts a filename specification as part of
2413 its argument, limiting the functions selected by the regex to those
2414 in the specified file.
2416 * Support for remote debugging Windows and SymbianOS shared libraries
2417 from Unix hosts has been improved. Non Windows GDB builds now can
2418 understand target reported file names that follow MS-DOS based file
2419 system semantics, such as file names that include drive letters and
2420 use the backslash character as directory separator. This makes it
2421 possible to transparently use the "set sysroot" and "set
2422 solib-search-path" on Unix hosts to point as host copies of the
2423 target's shared libraries. See the new command "set
2424 target-file-system-kind" described below, and the "Commands to
2425 specify files" section in the user manual for more information.
2429 eval template, expressions...
2430 Convert the values of one or more expressions under the control
2431 of the string template to a command line, and call it.
2433 set target-file-system-kind unix|dos-based|auto
2434 show target-file-system-kind
2435 Set or show the assumed file system kind for target reported file
2438 save breakpoints <filename>
2439 Save all current breakpoint definitions to a file suitable for use
2440 in a later debugging session. To read the saved breakpoint
2441 definitions, use the `source' command.
2443 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2446 info static-tracepoint-markers
2447 Display information about static tracepoint markers in the target.
2449 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2450 Define a static tracepoint by probing a marker at the given
2451 function, line, address, or marker ID.
2455 Enable and disable observer mode.
2457 set may-write-registers on|off
2458 set may-write-memory on|off
2459 set may-insert-breakpoints on|off
2460 set may-insert-tracepoints on|off
2461 set may-insert-fast-tracepoints on|off
2462 set may-interrupt on|off
2463 Set individual permissions for GDB effects on the target. Note that
2464 some of these settings can have undesirable or surprising
2465 consequences, particularly when changed in the middle of a session.
2466 For instance, disabling the writing of memory can prevent
2467 breakpoints from being inserted, cause single-stepping to fail, or
2468 even crash your program, if you disable after breakpoints have been
2469 inserted. However, GDB should not crash.
2471 set record memory-query on|off
2472 show record memory-query
2473 Control whether to stop the inferior if memory changes caused
2474 by an instruction cannot be recorded.
2479 The disassemble command now supports "start,+length" form of two arguments.
2483 ** GDB now provides a new directory location, called the python directory,
2484 where Python scripts written for GDB can be installed. The location
2485 of that directory is <data-directory>/python, where <data-directory>
2486 is the GDB data directory. For more details, see section `Scripting
2487 GDB using Python' in the manual.
2489 ** The GDB Python API now has access to breakpoints, symbols, symbol
2490 tables, program spaces, inferiors, threads and frame's code blocks.
2491 Additionally, GDB Parameters can now be created from the API, and
2492 manipulated via set/show in the CLI.
2494 ** New functions gdb.target_charset, gdb.target_wide_charset,
2495 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2497 ** New exception gdb.GdbError.
2499 ** Pretty-printers are now also looked up in the current program space.
2501 ** Pretty-printers can now be individually enabled and disabled.
2503 ** GDB now looks for names of Python scripts to auto-load in a
2504 special section named `.debug_gdb_scripts', in addition to looking
2505 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2507 * Tracepoint actions were unified with breakpoint commands. In particular,
2508 there are no longer differences in "info break" output for breakpoints and
2509 tracepoints and the "commands" command can be used for both tracepoints and
2510 regular breakpoints.
2514 ARM Symbian arm*-*-symbianelf*
2516 * D language support.
2517 GDB now supports debugging programs written in the D programming
2520 * GDB now supports the extended ptrace interface for PowerPC which is
2521 available since Linux kernel version 2.6.34. This automatically enables
2522 any hardware breakpoints and additional hardware watchpoints available in
2523 the processor. The old ptrace interface exposes just one hardware
2524 watchpoint and no hardware breakpoints.
2526 * GDB is now able to use the Data Value Compare (DVC) register available on
2527 embedded PowerPC processors to implement in hardware simple watchpoint
2528 conditions of the form:
2530 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2532 This works in native GDB running on Linux kernels with the extended ptrace
2533 interface mentioned above.
2535 *** Changes in GDB 7.1
2539 ** Namespace Support
2541 GDB now supports importing of namespaces in C++. This enables the
2542 user to inspect variables from imported namespaces. Support for
2543 namepace aliasing has also been added. So, if a namespace is
2544 aliased in the current scope (e.g. namepace C=A; ) the user can
2545 print variables using the alias (e.g. (gdb) print C::x).
2549 All known bugs relating to the printing of virtual base class were
2550 fixed. It is now possible to call overloaded static methods using a
2555 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2556 and reinterpret_cast<> are now handled by the C++ expression parser.
2560 Xilinx MicroBlaze microblaze-*-*
2565 Xilinx MicroBlaze microblaze
2568 * Multi-program debugging.
2570 GDB now has support for multi-program (a.k.a. multi-executable or
2571 multi-exec) debugging. This allows for debugging multiple inferiors
2572 simultaneously each running a different program under the same GDB
2573 session. See "Debugging Multiple Inferiors and Programs" in the
2574 manual for more information. This implied some user visible changes
2575 in the multi-inferior support. For example, "info inferiors" now
2576 lists inferiors that are not running yet or that have exited
2577 already. See also "New commands" and "New options" below.
2579 * New tracing features
2581 GDB's tracepoint facility now includes several new features:
2583 ** Trace state variables
2585 GDB tracepoints now include support for trace state variables, which
2586 are variables managed by the target agent during a tracing
2587 experiment. They are useful for tracepoints that trigger each
2588 other, so for instance one tracepoint can count hits in a variable,
2589 and then a second tracepoint has a condition that is true when the
2590 count reaches a particular value. Trace state variables share the
2591 $-syntax of GDB convenience variables, and can appear in both
2592 tracepoint actions and condition expressions. Use the "tvariable"
2593 command to create, and "info tvariables" to view; see "Trace State
2594 Variables" in the manual for more detail.
2598 GDB now includes an option for defining fast tracepoints, which
2599 targets may implement more efficiently, such as by installing a jump
2600 into the target agent rather than a trap instruction. The resulting
2601 speedup can be by two orders of magnitude or more, although the
2602 tradeoff is that some program locations on some target architectures
2603 might not allow fast tracepoint installation, for instance if the
2604 instruction to be replaced is shorter than the jump. To request a
2605 fast tracepoint, use the "ftrace" command, with syntax identical to
2606 the regular trace command.
2608 ** Disconnected tracing
2610 It is now possible to detach GDB from the target while it is running
2611 a trace experiment, then reconnect later to see how the experiment
2612 is going. In addition, a new variable disconnected-tracing lets you
2613 tell the target agent whether to continue running a trace if the
2614 connection is lost unexpectedly.
2618 GDB now has the ability to save the trace buffer into a file, and
2619 then use that file as a target, similarly to you can do with
2620 corefiles. You can select trace frames, print data that was
2621 collected in them, and use tstatus to display the state of the
2622 tracing run at the moment that it was saved. To create a trace
2623 file, use "tsave <filename>", and to use it, do "target tfile
2626 ** Circular trace buffer
2628 You can ask the target agent to handle the trace buffer as a
2629 circular buffer, discarding the oldest trace frames to make room for
2630 newer ones, by setting circular-trace-buffer to on. This feature may
2631 not be available for all target agents.
2636 The disassemble command, when invoked with two arguments, now requires
2637 the arguments to be comma-separated.
2640 The info variables command now displays variable definitions. Files
2641 which only declare a variable are not shown.
2644 The source command is now capable of sourcing Python scripts.
2645 This feature is dependent on the debugger being build with Python
2648 Related to this enhancement is also the introduction of a new command
2649 "set script-extension" (see below).
2651 * New commands (for set/show, see "New options" below)
2653 record save [<FILENAME>]
2654 Save a file (in core file format) containing the process record
2655 execution log for replay debugging at a later time.
2657 record restore <FILENAME>
2658 Restore the process record execution log that was saved at an
2659 earlier time, for replay debugging.
2661 add-inferior [-copies <N>] [-exec <FILENAME>]
2664 clone-inferior [-copies <N>] [ID]
2665 Make a new inferior ready to execute the same program another
2666 inferior has loaded.
2671 maint info program-spaces
2672 List the program spaces loaded into GDB.
2674 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2675 show remote interrupt-sequence
2676 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2677 as the sequence to the remote target in order to interrupt the execution.
2678 Ctrl-C is a default. Some system prefers BREAK which is high level of
2679 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2680 Magic SysRq g. It is BREAK signal and character 'g'.
2682 set remote interrupt-on-connect [on | off]
2683 show remote interrupt-on-connect
2684 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2685 remote target when gdb connects to it. This is needed when you debug
2688 set remotebreak [on | off]
2690 Deprecated. Use "set/show remote interrupt-sequence" instead.
2692 tvariable $NAME [ = EXP ]
2693 Create or modify a trace state variable.
2696 List trace state variables and their values.
2698 delete tvariable $NAME ...
2699 Delete one or more trace state variables.
2702 Evaluate the given expressions without collecting anything into the
2703 trace buffer. (Valid in tracepoint actions only.)
2705 ftrace FN / FILE:LINE / *ADDR
2706 Define a fast tracepoint at the given function, line, or address.
2708 * New expression syntax
2710 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2711 GDB now parses 0b101010 identically with 42.
2715 set follow-exec-mode new|same
2716 show follow-exec-mode
2717 Control whether GDB reuses the same inferior across an exec call or
2718 creates a new one. This is useful to be able to restart the old
2719 executable after the inferior having done an exec call.
2721 set default-collect EXPR, ...
2722 show default-collect
2723 Define a list of expressions to be collected at each tracepoint.
2724 This is a useful way to ensure essential items are not overlooked,
2725 such as registers or a critical global variable.
2727 set disconnected-tracing
2728 show disconnected-tracing
2729 If set to 1, the target is instructed to continue tracing if it
2730 loses its connection to GDB. If 0, the target is to stop tracing
2733 set circular-trace-buffer
2734 show circular-trace-buffer
2735 If set to on, the target is instructed to use a circular trace buffer
2736 and discard the oldest trace frames instead of stopping the trace due
2737 to a full trace buffer. If set to off, the trace stops when the buffer
2738 fills up. Some targets may not support this.
2740 set script-extension off|soft|strict
2741 show script-extension
2742 If set to "off", the debugger does not perform any script language
2743 recognition, and all sourced files are assumed to be GDB scripts.
2744 If set to "soft" (the default), files are sourced according to
2745 filename extension, falling back to GDB scripts if the first
2747 If set to "strict", files are sourced according to filename extension.
2749 set ada trust-PAD-over-XVS on|off
2750 show ada trust-PAD-over-XVS
2751 If off, activate a workaround against a bug in the debugging information
2752 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2753 the GCC sources for more information about the GNAT encoding and
2754 PAD types in particular). It is always safe to set this option to
2755 off, but this introduces a slight performance penalty. The default
2758 * Python API Improvements
2760 ** GDB provides the new class gdb.LazyString. This is useful in
2761 some pretty-printing cases. The new method gdb.Value.lazy_string
2762 provides a simple way to create objects of this type.
2764 ** The fields returned by gdb.Type.fields now have an
2765 `is_base_class' attribute.
2767 ** The new method gdb.Type.range returns the range of an array type.
2769 ** The new method gdb.parse_and_eval can be used to parse and
2770 evaluate an expression.
2772 * New remote packets
2775 Define a trace state variable.
2778 Get the current value of a trace state variable.
2781 Set desired tracing behavior upon disconnection.
2784 Set the trace buffer to be linear or circular.
2787 Get data about the tracepoints currently in use.
2791 Process record now works correctly with hardware watchpoints.
2793 Multiple bug fixes have been made to the mips-irix port, making it
2794 much more reliable. In particular:
2795 - Debugging threaded applications is now possible again. Previously,
2796 GDB would hang while starting the program, or while waiting for
2797 the program to stop at a breakpoint.
2798 - Attaching to a running process no longer hangs.
2799 - An error occurring while loading a core file has been fixed.
2800 - Changing the value of the PC register now works again. This fixes
2801 problems observed when using the "jump" command, or when calling
2802 a function from GDB, or even when assigning a new value to $pc.
2803 - With the "finish" and "return" commands, the return value for functions
2804 returning a small array is now correctly printed.
2805 - It is now possible to break on shared library code which gets executed
2806 during a shared library init phase (code executed while executing
2807 their .init section). Previously, the breakpoint would have no effect.
2808 - GDB is now able to backtrace through the signal handler for
2809 non-threaded programs.
2811 PIE (Position Independent Executable) programs debugging is now supported.
2812 This includes debugging execution of PIC (Position Independent Code) shared
2813 libraries although for that, it should be possible to run such libraries as an
2816 *** Changes in GDB 7.0
2818 * GDB now has an interface for JIT compilation. Applications that
2819 dynamically generate code can create symbol files in memory and register
2820 them with GDB. For users, the feature should work transparently, and
2821 for JIT developers, the interface is documented in the GDB manual in the
2822 "JIT Compilation Interface" chapter.
2824 * Tracepoints may now be conditional. The syntax is as for
2825 breakpoints; either an "if" clause appended to the "trace" command,
2826 or the "condition" command is available. GDB sends the condition to
2827 the target for evaluation using the same bytecode format as is used
2828 for tracepoint actions.
2830 * The disassemble command now supports: an optional /r modifier, print the
2831 raw instructions in hex as well as in symbolic form, and an optional /m
2832 modifier to print mixed source+assembly.
2834 * Process record and replay
2836 In a architecture environment that supports ``process record and
2837 replay'', ``process record and replay'' target can record a log of
2838 the process execution, and replay it with both forward and reverse
2841 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2842 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2843 set execution-direction {forward|reverse}, for targets that support
2846 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2847 feature is available with a native GDB running on kernel version
2850 * GDB now has support for multi-byte and wide character sets on the
2851 target. Strings whose character type is wchar_t, char16_t, or
2852 char32_t are now correctly printed. GDB supports wide- and unicode-
2853 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2854 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2855 `printf'. This feature requires iconv to work properly; if your
2856 system does not have a working iconv, GDB can use GNU libiconv. See
2857 the installation instructions for more information.
2859 * GDB now supports automatic retrieval of shared library files from
2860 remote targets. To use this feature, specify a system root that begins
2861 with the `remote:' prefix, either via the `set sysroot' command or via
2862 the `--with-sysroot' configure-time option.
2864 * "info sharedlibrary" now takes an optional regex of libraries to show,
2865 and it now reports if a shared library has no debugging information.
2867 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2868 now complete on file names.
2870 * When completing in expressions, gdb will attempt to limit
2871 completions to allowable structure or union fields, where appropriate.
2872 For instance, consider:
2874 # struct example { int f1; double f2; };
2875 # struct example variable;
2878 If the user types TAB at the end of this command line, the available
2879 completions will be "f1" and "f2".
2881 * Inlined functions are now supported. They show up in backtraces, and
2882 the "step", "next", and "finish" commands handle them automatically.
2884 * GDB now supports the token-splicing (##) and stringification (#)
2885 operators when expanding macros. It also supports variable-arity
2888 * GDB now supports inspecting extra signal information, exported by
2889 the new $_siginfo convenience variable. The feature is currently
2890 implemented on linux ARM, i386 and amd64.
2892 * GDB can now display the VFP floating point registers and NEON vector
2893 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2894 can provide these registers (requires Linux 2.6.30 or later). Remote
2895 and simulator targets may also provide them.
2897 * New remote packets
2900 Search memory for a sequence of bytes.
2903 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2904 operation over reliable transport links. Use of this packet is
2905 controlled by the `set remote noack-packet' command.
2908 Kill the process with the specified process ID. Use this in preference
2909 to `k' when multiprocess protocol extensions are supported.
2912 Obtains additional operating system information
2916 Read or write additional signal information.
2918 * Removed remote protocol undocumented extension
2920 An undocumented extension to the remote protocol's `S' stop reply
2921 packet that permited the stub to pass a process id was removed.
2922 Remote servers should use the `T' stop reply packet instead.
2924 * GDB now supports multiple function calling conventions according to the
2925 DWARF-2 DW_AT_calling_convention function attribute.
2927 * The SH target utilizes the aforementioned change to distinguish between gcc
2928 and Renesas calling convention. It also adds the new CLI commands
2929 `set/show sh calling-convention'.
2931 * GDB can now read compressed debug sections, as produced by GNU gold
2932 with the --compress-debug-sections=zlib flag.
2934 * 64-bit core files are now supported on AIX.
2936 * Thread switching is now supported on Tru64.
2938 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2939 which will be allocated using malloc later in program execution.
2941 * The qXfer:libraries:read remote procotol packet now allows passing a
2942 list of section offsets.
2944 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2945 conditions handling signals delivered during attach or thread creation
2946 have also been fixed.
2948 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2949 From the user's standpoint, all unqualified instances of True and False
2950 are treated as the standard definitions, regardless of context.
2952 * GDB now parses C++ symbol and type names more flexibly. For
2955 template<typename T> class C { };
2958 GDB will now correctly handle all of:
2960 ptype C<char const *>
2961 ptype C<char const*>
2962 ptype C<const char *>
2963 ptype C<const char*>
2965 * New features in the GDB remote stub, gdbserver
2967 - The "--wrapper" command-line argument tells gdbserver to use a
2968 wrapper program to launch programs for debugging.
2970 - On PowerPC and S/390 targets, it is now possible to use a single
2971 gdbserver executable to debug both 32-bit and 64-bit programs.
2972 (This requires gdbserver itself to be built as a 64-bit executable.)
2974 - gdbserver uses the new noack protocol mode for TCP connections to
2975 reduce communications latency, if also supported and enabled in GDB.
2977 - Support for the sparc64-linux-gnu target is now included in
2980 - The amd64-linux build of gdbserver now supports debugging both
2981 32-bit and 64-bit programs.
2983 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2984 now support hardware watchpoints, and will use them automatically
2989 GDB now has support for scripting using Python. Whether this is
2990 available is determined at configure time.
2992 New GDB commands can now be written in Python.
2994 * Ada tasking support
2996 Ada tasks can now be inspected in GDB. The following commands have
3000 Print the list of Ada tasks.
3002 Print detailed information about task number N.
3004 Print the task number of the current task.
3006 Switch the context of debugging to task number N.
3008 * Support for user-defined prefixed commands. The "define" command can
3009 add new commands to existing prefixes, e.g. "target".
3011 * Multi-inferior, multi-process debugging.
3013 GDB now has generalized support for multi-inferior debugging. See
3014 "Debugging Multiple Inferiors" in the manual for more information.
3015 Although availability still depends on target support, the command
3016 set is more uniform now. The GNU/Linux specific multi-forks support
3017 has been migrated to this new framework. This implied some user
3018 visible changes; see "New commands" and also "Removed commands"
3021 * Target descriptions can now describe the target OS ABI. See the
3022 "Target Description Format" section in the user manual for more
3025 * Target descriptions can now describe "compatible" architectures
3026 to indicate that the target can execute applications for a different
3027 architecture in addition to those for the main target architecture.
3028 See the "Target Description Format" section in the user manual for
3031 * Multi-architecture debugging.
3033 GDB now includes general supports for debugging applications on
3034 hybrid systems that use more than one single processor architecture
3035 at the same time. Each such hybrid architecture still requires
3036 specific support to be added. The only hybrid architecture supported
3037 in this version of GDB is the Cell Broadband Engine.
3039 * GDB now supports integrated debugging of Cell/B.E. applications that
3040 use both the PPU and SPU architectures. To enable support for hybrid
3041 Cell/B.E. debugging, you need to configure GDB to support both the
3042 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3043 --enable-targets configure option.
3045 * Non-stop mode debugging.
3047 For some targets, GDB now supports an optional mode of operation in
3048 which you can examine stopped threads while other threads continue
3049 to execute freely. This is referred to as non-stop mode, with the
3050 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3051 section in the user manual for more information.
3053 To be able to support remote non-stop debugging, a remote stub needs
3054 to implement the non-stop mode remote protocol extensions, as
3055 described in the "Remote Non-Stop" section of the user manual. The
3056 GDB remote stub, gdbserver, has been adjusted to support these
3057 extensions on linux targets.
3059 * New commands (for set/show, see "New options" below)
3061 catch syscall [NAME(S) | NUMBER(S)]
3062 Catch system calls. Arguments, which should be names of system
3063 calls or their numbers, mean catch only those syscalls. Without
3064 arguments, every syscall will be caught. When the inferior issues
3065 any of the specified syscalls, GDB will stop and announce the system
3066 call, both when it is called and when its call returns. This
3067 feature is currently available with a native GDB running on the
3068 Linux Kernel, under the following architectures: x86, x86_64,
3069 PowerPC and PowerPC64.
3071 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3073 Search memory for a sequence of bytes.
3075 maint set python print-stack
3076 maint show python print-stack
3077 Show a stack trace when an error is encountered in a Python script.
3080 Invoke CODE by passing it to the Python interpreter.
3085 These allow macros to be defined, undefined, and listed
3089 Show operating system information about processes.
3092 List the inferiors currently under GDB's control.
3095 Switch focus to inferior number NUM.
3098 Detach from inferior number NUM.
3101 Kill inferior number NUM.
3105 set spu stop-on-load
3106 show spu stop-on-load
3107 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3109 set spu auto-flush-cache
3110 show spu auto-flush-cache
3111 Control whether to automatically flush the software-managed cache
3112 during Cell/B.E. debugging.
3114 set sh calling-convention
3115 show sh calling-convention
3116 Control the calling convention used when calling SH target functions.
3119 show debug timestamp
3120 Control display of timestamps with GDB debugging output.
3122 set disassemble-next-line
3123 show disassemble-next-line
3124 Control display of disassembled source lines or instructions when
3127 set remote noack-packet
3128 show remote noack-packet
3129 Set/show the use of remote protocol QStartNoAckMode packet. See above
3130 under "New remote packets."
3132 set remote query-attached-packet
3133 show remote query-attached-packet
3134 Control use of remote protocol `qAttached' (query-attached) packet.
3136 set remote read-siginfo-object
3137 show remote read-siginfo-object
3138 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3141 set remote write-siginfo-object
3142 show remote write-siginfo-object
3143 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3146 set remote reverse-continue
3147 show remote reverse-continue
3148 Control use of remote protocol 'bc' (reverse-continue) packet.
3150 set remote reverse-step
3151 show remote reverse-step
3152 Control use of remote protocol 'bs' (reverse-step) packet.
3154 set displaced-stepping
3155 show displaced-stepping
3156 Control displaced stepping mode. Displaced stepping is a way to
3157 single-step over breakpoints without removing them from the debuggee.
3158 Also known as "out-of-line single-stepping".
3161 show debug displaced
3162 Control display of debugging info for displaced stepping.
3164 maint set internal-error
3165 maint show internal-error
3166 Control what GDB does when an internal error is detected.
3168 maint set internal-warning
3169 maint show internal-warning
3170 Control what GDB does when an internal warning is detected.
3175 Use a wrapper program to launch programs for debugging.
3177 set multiple-symbols (all|ask|cancel)
3178 show multiple-symbols
3179 The value of this variable can be changed to adjust the debugger behavior
3180 when an expression or a breakpoint location contains an ambiguous symbol
3181 name (an overloaded function name, for instance).
3183 set breakpoint always-inserted
3184 show breakpoint always-inserted
3185 Keep breakpoints always inserted in the target, as opposed to inserting
3186 them when resuming the target, and removing them when the target stops.
3187 This option can improve debugger performance on slow remote targets.
3189 set arm fallback-mode (arm|thumb|auto)
3190 show arm fallback-mode
3191 set arm force-mode (arm|thumb|auto)
3193 These commands control how ARM GDB determines whether instructions
3194 are ARM or Thumb. The default for both settings is auto, which uses
3195 the current CPSR value for instructions without symbols; previous
3196 versions of GDB behaved as if "set arm fallback-mode arm".
3198 set disable-randomization
3199 show disable-randomization
3200 Standalone programs run with the virtual address space randomization enabled
3201 by default on some platforms. This option keeps the addresses stable across
3202 multiple debugging sessions.
3206 Control whether other threads are stopped or not when some thread hits
3211 Requests that asynchronous execution is enabled in the target, if available.
3212 In this case, it's possible to resume target in the background, and interact
3213 with GDB while the target is running. "show target-async" displays the
3214 current state of asynchronous execution of the target.
3216 set target-wide-charset
3217 show target-wide-charset
3218 The target-wide-charset is the name of the character set that GDB
3219 uses when printing characters whose type is wchar_t.
3221 set tcp auto-retry (on|off)
3223 set tcp connect-timeout
3224 show tcp connect-timeout
3225 These commands allow GDB to retry failed TCP connections to a remote stub
3226 with a specified timeout period; this is useful if the stub is launched
3227 in parallel with GDB but may not be ready to accept connections immediately.
3229 set libthread-db-search-path
3230 show libthread-db-search-path
3231 Control list of directories which GDB will search for appropriate
3234 set schedule-multiple (on|off)
3235 show schedule-multiple
3236 Allow GDB to resume all threads of all processes or only threads of
3237 the current process.
3241 Use more aggressive caching for accesses to the stack. This improves
3242 performance of remote debugging (particularly backtraces) without
3243 affecting correctness.
3245 set interactive-mode (on|off|auto)
3246 show interactive-mode
3247 Control whether GDB runs in interactive mode (on) or not (off).
3248 When in interactive mode, GDB waits for the user to answer all
3249 queries. Otherwise, GDB does not wait and assumes the default
3250 answer. When set to auto (the default), GDB determines which
3251 mode to use based on the stdin settings.
3256 For program forks, this is replaced by the new more generic `info
3257 inferiors' command. To list checkpoints, you can still use the
3258 `info checkpoints' command, which was an alias for the `info forks'
3262 Replaced by the new `inferior' command. To switch between
3263 checkpoints, you can still use the `restart' command, which was an
3264 alias for the `fork' command.
3267 This is removed, since some targets don't have a notion of
3268 processes. To switch between processes, you can still use the
3269 `inferior' command using GDB's own inferior number.
3272 For program forks, this is replaced by the new more generic `kill
3273 inferior' command. To delete a checkpoint, you can still use the
3274 `delete checkpoint' command, which was an alias for the `delete
3278 For program forks, this is replaced by the new more generic `detach
3279 inferior' command. To detach a checkpoint, you can still use the
3280 `detach checkpoint' command, which was an alias for the `detach
3283 * New native configurations
3285 x86/x86_64 Darwin i[34567]86-*-darwin*
3287 x86_64 MinGW x86_64-*-mingw*
3291 Lattice Mico32 lm32-*
3292 x86 DICOS i[34567]86-*-dicos*
3293 x86_64 DICOS x86_64-*-dicos*
3296 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3297 (mingw32ce) debugging.
3303 These commands were actually not implemented on any target.
3305 *** Changes in GDB 6.8
3307 * New native configurations
3309 NetBSD/hppa hppa*-*netbsd*
3310 Xtensa GNU/Linux xtensa*-*-linux*
3314 NetBSD/hppa hppa*-*-netbsd*
3315 Xtensa GNU/Lunux xtensa*-*-linux*
3317 * Change in command line behavior -- corefiles vs. process ids.
3319 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3320 attaching to process NUMBER fails, GDB no longer attempts to open a
3321 core file named NUMBER. Attaching to a program using the -c option
3322 is no longer supported. Instead, use the '-p' or '--pid' options.
3324 * GDB can now be built as a native debugger for debugging Windows x86
3325 (mingw32) Portable Executable (PE) programs.
3327 * Pending breakpoints no longer change their number when their address
3330 * GDB now supports breakpoints with multiple locations,
3331 including breakpoints on C++ constructors, inside C++ templates,
3332 and in inlined functions.
3334 * GDB's ability to debug optimized code has been improved. GDB more
3335 accurately identifies function bodies and lexical blocks that occupy
3336 more than one contiguous range of addresses.
3338 * Target descriptions can now describe registers for PowerPC.
3340 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3341 registers on PowerPC targets.
3343 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3344 targets even when the libthread_db library is not available.
3346 * The GDB remote stub, gdbserver, now supports the new file transfer
3347 commands (remote put, remote get, and remote delete).
3349 * The GDB remote stub, gdbserver, now supports run and attach in
3350 extended-remote mode.
3352 * hppa*64*-*-hpux11* target broken
3353 The debugger is unable to start a program and fails with the following
3354 error: "Error trying to get information about dynamic linker".
3355 The gdb-6.7 release is also affected.
3357 * GDB now supports the --enable-targets= configure option to allow
3358 building a single GDB executable that supports multiple remote
3359 target architectures.
3361 * GDB now supports debugging C and C++ programs which use the
3362 Decimal Floating Point extension. In addition, the PowerPC target
3363 now has a set of pseudo-registers to inspect decimal float values
3364 stored in two consecutive float registers.
3366 * The -break-insert MI command can optionally create pending
3369 * Improved support for debugging Ada
3370 Many improvements to the Ada language support have been made. These
3372 - Better support for Ada2005 interface types
3373 - Improved handling of arrays and slices in general
3374 - Better support for Taft-amendment types
3375 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3377 - Improved command completion in Ada
3380 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3385 set print frame-arguments (all|scalars|none)
3386 show print frame-arguments
3387 The value of this variable can be changed to control which argument
3388 values should be printed by the debugger when displaying a frame.
3393 Transfer files to and from a remote target, and delete remote files.
3400 Transfer files to and from a remote target, and delete remote files.
3402 * New remote packets
3409 Open, close, read, write, and delete files on the remote system.
3412 Attach to an existing process on the remote system, in extended-remote
3416 Run a new process on the remote system, in extended-remote mode.
3418 *** Changes in GDB 6.7
3420 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3421 bfd, libiberty and opcodes, as revealed by static analysis donated by
3422 Coverity, Inc. (http://scan.coverity.com).
3424 * When looking up multiply-defined global symbols, GDB will now prefer the
3425 symbol definition in the current shared library if it was built using the
3426 -Bsymbolic linker option.
3428 * When the Text User Interface (TUI) is not configured, GDB will now
3429 recognize the -tui command-line option and print a message that the TUI
3432 * The GDB remote stub, gdbserver, now has lower overhead for high
3433 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3435 * GDB for MIPS targets now autodetects whether a remote target provides
3436 32-bit or 64-bit register values.
3438 * Support for C++ member pointers has been improved.
3440 * GDB now understands XML target descriptions, which specify the
3441 target's overall architecture. GDB can read a description from
3442 a local file or over the remote serial protocol.
3444 * Vectors of single-byte data use a new integer type which is not
3445 automatically displayed as character or string data.
3447 * The /s format now works with the print command. It displays
3448 arrays of single-byte integers and pointers to single-byte integers
3451 * Target descriptions can now describe target-specific registers,
3452 for architectures which have implemented the support (currently
3453 only ARM, M68K, and MIPS).
3455 * GDB and the GDB remote stub, gdbserver, now support the XScale
3458 * The GDB remote stub, gdbserver, has been updated to support
3459 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3460 has been rewritten to use the standard GDB remote protocol.
3462 * GDB can now step into C++ functions which are called through thunks.
3464 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3466 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3467 layout. It also supports a TextSeg= and DataSeg= response when only
3468 segment base addresses (rather than offsets) are available.
3470 * The /i format now outputs any trailing branch delay slot instructions
3471 immediately following the last instruction within the count specified.
3473 * The GDB remote protocol "T" stop reply packet now supports a
3474 "library" response. Combined with the new "qXfer:libraries:read"
3475 packet, this response allows GDB to debug shared libraries on targets
3476 where the operating system manages the list of loaded libraries (e.g.
3477 Windows and SymbianOS).
3479 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3480 (DLLs) on Windows and Windows CE targets.
3482 * GDB now supports a faster verification that a .debug file matches its binary
3483 according to its build-id signature, if the signature is present.
3489 Enable or disable hardware flow control (RTS/CTS) on the serial port
3490 when debugging using remote targets.
3492 set mem inaccessible-by-default
3493 show mem inaccessible-by-default
3494 If the target supplies a memory map, for instance via the remote
3495 protocol's "qXfer:memory-map:read" packet, setting this variable
3496 prevents GDB from accessing memory outside the memory map. This
3497 is useful for targets with memory mapped registers or which react
3498 badly to accesses of unmapped address space.
3500 set breakpoint auto-hw
3501 show breakpoint auto-hw
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 lets GDB use hardware breakpoints automatically for memory regions
3505 where it can not use software breakpoints. This covers both the
3506 "break" command and internal breakpoints used for other commands
3507 including "next" and "finish".
3510 catch exception unhandled
3511 Stop the program execution when Ada exceptions are raised.
3514 Stop the program execution when an Ada assertion failed.
3518 Set an alternate system root for target files. This is a more
3519 general version of "set solib-absolute-prefix", which is now
3520 an alias to "set sysroot".
3523 Provide extended SPU facility status information. This set of
3524 commands is available only when debugging the Cell/B.E. SPU
3527 * New native configurations
3529 OpenBSD/sh sh*-*openbsd*
3532 unset tdesc filename
3534 Use the specified local file as an XML target description, and do
3535 not query the target for its built-in description.
3539 OpenBSD/sh sh*-*-openbsd*
3540 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3541 Toshiba Media Processor mep-elf
3543 * New remote packets
3546 Ignore the specified signals; pass them directly to the debugged program
3547 without stopping other threads or reporting them to GDB.
3549 qXfer:features:read:
3550 Read an XML target description from the target, which describes its
3555 Read or write contents of an spufs file on the target system. These
3556 packets are available only on the Cell/B.E. SPU architecture.
3558 qXfer:libraries:read:
3559 Report the loaded shared libraries. Combined with new "T" packet
3560 response, this packet allows GDB to debug shared libraries on
3561 targets where the operating system manages the list of loaded
3562 libraries (e.g. Windows and SymbianOS).
3566 Support for these obsolete configurations has been removed.
3574 i[34567]86-*-lynxos*
3575 i[34567]86-*-netware*
3576 i[34567]86-*-sco3.2v5*
3577 i[34567]86-*-sco3.2v4*
3579 i[34567]86-*-sysv4.2*
3582 i[34567]86-*-unixware2*
3583 i[34567]86-*-unixware*
3592 * Other removed features
3599 Various m68k-only ROM monitors.
3606 Various Renesas ROM monitors and debugging interfaces for SH and
3611 Support for a Macraigor serial interface to on-chip debugging.
3612 GDB does not directly support the newer parallel or USB
3617 A debug information format. The predecessor to DWARF 2 and
3618 DWARF 3, which are still supported.
3620 Support for the HP aCC compiler on HP-UX/PA-RISC
3622 SOM-encapsulated symbolic debugging information, automatic
3623 invocation of pxdb, and the aCC custom C++ ABI. This does not
3624 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3625 with aCC can still be debugged on an assembly level.
3627 MIPS ".pdr" sections
3629 A MIPS-specific format used to describe stack frame layout
3630 in debugging information.
3634 GDB could work with an older version of Guile to debug
3635 the interpreter and Scheme programs running in it.
3637 set mips stack-arg-size
3638 set mips saved-gpreg-size
3640 Use "set mips abi" to control parameter passing for MIPS.
3642 *** Changes in GDB 6.6
3647 Cell Broadband Engine SPU spu-elf
3649 * GDB can now be configured as a cross-debugger targeting native Windows
3650 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3651 running on a Windows system over TCP/IP to debug Windows programs.
3653 * The GDB remote stub, gdbserver, has been updated to support Windows and
3654 Cygwin debugging. Both single-threaded and multi-threaded programs are
3657 * The "set trust-readonly-sections" command works again. This command was
3658 broken in GDB 6.3, 6.4, and 6.5.
3660 * The "load" command now supports writing to flash memory, if the remote
3661 stub provides the required support.
3663 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3664 longer requires symbolic debug information (e.g. DWARF-2).
3669 unset substitute-path
3670 show substitute-path
3671 Manage a list of substitution rules that GDB uses to rewrite the name
3672 of the directories where the sources are located. This can be useful
3673 for instance when the sources were moved to a different location
3674 between compilation and debugging.
3678 Print each CLI command as it is executed. Each command is prefixed with
3679 a number of `+' symbols representing the nesting depth.
3680 The source command now has a `-v' option to enable the same feature.
3684 The ARM Demon monitor support (RDP protocol, "target rdp").
3686 Kernel Object Display, an embedded debugging feature which only worked with
3687 an obsolete version of Cisco IOS.
3689 The 'set download-write-size' and 'show download-write-size' commands.
3691 * New remote packets
3694 Tell a stub about GDB client features, and request remote target features.
3695 The first feature implemented is PacketSize, which allows the target to
3696 specify the size of packets it can handle - to minimize the number of
3697 packets required and improve performance when connected to a remote
3701 Fetch an OS auxilliary vector from the remote stub. This packet is a
3702 more efficient replacement for qPart:auxv:read.
3704 qXfer:memory-map:read:
3705 Fetch a memory map from the remote stub, including information about
3706 RAM, ROM, and flash memory devices.
3711 Erase and program a flash memory device.
3713 * Removed remote packets
3716 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3717 used it, and only gdbserver implemented it.
3719 *** Changes in GDB 6.5
3723 Renesas M32C/M16C m32c-elf
3725 Morpho Technologies ms1 ms1-elf
3729 init-if-undefined Initialize a convenience variable, but
3730 only if it doesn't already have a value.
3732 The following commands are presently only implemented for native GNU/Linux:
3734 checkpoint Save a snapshot of the program state.
3736 restart <n> Return the program state to a
3737 previously saved state.
3739 info checkpoints List currently saved checkpoints.
3741 delete-checkpoint <n> Delete a previously saved checkpoint.
3743 set|show detach-on-fork Tell gdb whether to detach from a newly
3744 forked process, or to keep debugging it.
3746 info forks List forks of the user program that
3747 are available to be debugged.
3749 fork <n> Switch to debugging one of several
3750 forks of the user program that are
3751 available to be debugged.
3753 delete-fork <n> Delete a fork from the list of forks
3754 that are available to be debugged (and
3755 kill the forked process).
3757 detach-fork <n> Delete a fork from the list of forks
3758 that are available to be debugged (and
3759 allow the process to continue).
3763 Morpho Technologies ms2 ms1-elf
3765 * Improved Windows host support
3767 GDB now builds as a cross debugger hosted on i686-mingw32, including
3768 native console support, and remote communications using either
3769 network sockets or serial ports.
3771 * Improved Modula-2 language support
3773 GDB can now print most types in the Modula-2 syntax. This includes:
3774 basic types, set types, record types, enumerated types, range types,
3775 pointer types and ARRAY types. Procedure var parameters are correctly
3776 printed and hexadecimal addresses and character constants are also
3777 written in the Modula-2 syntax. Best results can be obtained by using
3778 GNU Modula-2 together with the -gdwarf-2 command line option.
3782 The ARM rdi-share module.
3784 The Netware NLM debug server.
3786 *** Changes in GDB 6.4
3788 * New native configurations
3790 OpenBSD/arm arm*-*-openbsd*
3791 OpenBSD/mips64 mips64-*-openbsd*
3795 Morpho Technologies ms1 ms1-elf
3797 * New command line options
3799 --batch-silent As for --batch, but totally silent.
3800 --return-child-result The debugger will exist with the same value
3801 the child (debugged) program exited with.
3802 --eval-command COMMAND, -ex COMMAND
3803 Execute a single GDB CLI command. This may be
3804 specified multiple times and in conjunction
3805 with the --command (-x) option.
3807 * Deprecated commands removed
3809 The following commands, that were deprecated in 2000, have been
3813 set|show arm disassembly-flavor set|show arm disassembler
3814 othernames set arm disassembler
3815 set|show remotedebug set|show debug remote
3816 set|show archdebug set|show debug arch
3817 set|show eventdebug set|show debug event
3820 * New BSD user-level threads support
3822 It is now possible to debug programs using the user-level threads
3823 library on OpenBSD and FreeBSD. Currently supported (target)
3826 FreeBSD/amd64 x86_64-*-freebsd*
3827 FreeBSD/i386 i386-*-freebsd*
3828 OpenBSD/i386 i386-*-openbsd*
3830 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3831 are not yet supported.
3833 * New support for Matsushita MN10300 w/sim added
3834 (Work in progress). mn10300-elf.
3836 * REMOVED configurations and files
3838 VxWorks and the XDR protocol *-*-vxworks
3839 Motorola MCORE mcore-*-*
3840 National Semiconductor NS32000 ns32k-*-*
3842 * New "set print array-indexes" command
3844 After turning this setting "on", GDB prints the index of each element
3845 when displaying arrays. The default is "off" to preserve the previous
3848 * VAX floating point support
3850 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3852 * User-defined command support
3854 In addition to using $arg0..$arg9 for argument passing, it is now possible
3855 to use $argc to determine now many arguments have been passed. See the
3856 section on user-defined commands in the user manual for more information.
3858 *** Changes in GDB 6.3:
3860 * New command line option
3862 GDB now accepts -l followed by a number to set the timeout for remote
3865 * GDB works with GCC -feliminate-dwarf2-dups
3867 GDB now supports a more compact representation of DWARF-2 debug
3868 information using DW_FORM_ref_addr references. These are produced
3869 by GCC with the option -feliminate-dwarf2-dups and also by some
3870 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3871 to use -feliminate-dwarf2-dups.
3873 * Internationalization
3875 When supported by the host system, GDB will be built with
3876 internationalization (libintl). The task of marking up the sources is
3877 continued, we're looking forward to our first translation.
3881 Initial support for debugging programs compiled with the GNAT
3882 implementation of the Ada programming language has been integrated
3883 into GDB. In this release, support is limited to expression evaluation.
3885 * New native configurations
3887 GNU/Linux/m32r m32r-*-linux-gnu
3891 GDB's remote protocol now includes support for the 'p' packet. This
3892 packet is used to fetch individual registers from a remote inferior.
3894 * END-OF-LIFE registers[] compatibility module
3896 GDB's internal register infrastructure has been completely rewritten.
3897 The new infrastructure making possible the implementation of key new
3898 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3901 GDB 6.3 will be the last release to include the the registers[]
3902 compatibility module that allowed out-of-date configurations to
3903 continue to work. This change directly impacts the following
3913 powerpc bdm protocol
3915 Unless there is activity to revive these configurations, they will be
3916 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3918 * OBSOLETE configurations and files
3920 Configurations that have been declared obsolete in this release have
3921 been commented out. Unless there is activity to revive these
3922 configurations, the next release of GDB will have their sources
3923 permanently REMOVED.
3932 *** Changes in GDB 6.2.1:
3934 * MIPS `break main; run' gave an heuristic-fence-post warning
3936 When attempting to run even a simple program, a warning about
3937 heuristic-fence-post being hit would be reported. This problem has
3940 * MIPS IRIX 'long double' crashed GDB
3942 When examining a long double variable, GDB would get a segmentation
3943 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3944 IRIX long double values).
3948 A bug in the VAX stack code was causing problems with the "next"
3949 command. This problem has been fixed.
3951 *** Changes in GDB 6.2:
3953 * Fix for ``many threads''
3955 On GNU/Linux systems that use the NPTL threads library, a program
3956 rapidly creating and deleting threads would confuse GDB leading to the
3959 ptrace: No such process.
3960 thread_db_get_info: cannot get thread info: generic error
3962 This problem has been fixed.
3964 * "-async" and "-noasync" options removed.
3966 Support for the broken "-noasync" option has been removed (it caused
3969 * New ``start'' command.
3971 This command runs the program until the begining of the main procedure.
3973 * New BSD Kernel Data Access Library (libkvm) interface
3975 Using ``target kvm'' it is now possible to debug kernel core dumps and
3976 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3977 platforms. Currently supported (native-only) configurations are:
3979 FreeBSD/amd64 x86_64-*-freebsd*
3980 FreeBSD/i386 i?86-*-freebsd*
3981 NetBSD/i386 i?86-*-netbsd*
3982 NetBSD/m68k m68*-*-netbsd*
3983 NetBSD/sparc sparc-*-netbsd*
3984 OpenBSD/amd64 x86_64-*-openbsd*
3985 OpenBSD/i386 i?86-*-openbsd*
3986 OpenBSD/m68k m68*-openbsd*
3987 OpenBSD/sparc sparc-*-openbsd*
3989 * Signal trampoline code overhauled
3991 Many generic problems with GDB's signal handling code have been fixed.
3992 These include: backtraces through non-contiguous stacks; recognition
3993 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3994 call; backtrace through a signal trampoline; step into and out of
3995 signal handlers; and single-stepping in the signal trampoline.
3997 Please note that kernel bugs are a limiting factor here. These
3998 features have been shown to work on an s390 GNU/Linux system that
3999 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4001 * Cygwin support for DWARF 2 added.
4003 * New native configurations
4005 GNU/Linux/hppa hppa*-*-linux*
4006 OpenBSD/hppa hppa*-*-openbsd*
4007 OpenBSD/m68k m68*-*-openbsd*
4008 OpenBSD/m88k m88*-*-openbsd*
4009 OpenBSD/powerpc powerpc-*-openbsd*
4010 NetBSD/vax vax-*-netbsd*
4011 OpenBSD/vax vax-*-openbsd*
4013 * END-OF-LIFE frame compatibility module
4015 GDB's internal frame infrastructure has been completely rewritten.
4016 The new infrastructure making it possible to support key new features
4017 including DWARF 2 Call Frame Information. To aid in the task of
4018 migrating old configurations to this new infrastructure, a
4019 compatibility module, that allowed old configurations to continue to
4020 work, was also included.
4022 GDB 6.2 will be the last release to include this frame compatibility
4023 module. This change directly impacts the following configurations:
4033 Unless there is activity to revive these configurations, they will be
4034 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4036 * REMOVED configurations and files
4038 Sun 3, running SunOS 3 m68*-*-sunos3*
4039 Sun 3, running SunOS 4 m68*-*-sunos4*
4040 Sun 2, running SunOS 3 m68000-*-sunos3*
4041 Sun 2, running SunOS 4 m68000-*-sunos4*
4042 Motorola 680x0 running LynxOS m68*-*-lynxos*
4043 AT&T 3b1/Unix pc m68*-att-*
4044 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4045 decstation mips-dec-* mips-little-*
4046 riscos mips-*-riscos* mips-*-sysv*
4047 sonymips mips-sony-*
4048 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4050 *** Changes in GDB 6.1.1:
4052 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4054 The TUI (Text-mode User Interface) is now built as part of a default
4055 GDB configuration. It is enabled by either selecting the TUI with the
4056 command line option "-i=tui" or by running the separate "gdbtui"
4057 program. For more information on the TUI, see the manual "Debugging
4060 * Pending breakpoint support (also included in GDB 6.1)
4062 Support has been added to allow you to specify breakpoints in shared
4063 libraries that have not yet been loaded. If a breakpoint location
4064 cannot be found, and the "breakpoint pending" option is set to auto,
4065 GDB queries you if you wish to make the breakpoint pending on a future
4066 shared-library load. If and when GDB resolves the breakpoint symbol,
4067 the pending breakpoint is removed as one or more regular breakpoints
4070 Pending breakpoints are very useful for GCJ Java debugging.
4072 * Fixed ISO-C build problems
4074 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4075 non ISO-C code that stopped them being built using a more strict ISO-C
4076 compiler (e.g., IBM's C compiler).
4078 * Fixed build problem on IRIX 5
4080 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4081 wasn't able to compile compile on an IRIX 5 system.
4083 * Added execute permission to gdb/gdbserver/configure
4085 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4086 permission. This bug would cause configure to fail on a number of
4087 systems (Solaris, IRIX). Ref: server/519.
4089 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4091 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4092 has been updated to use constant array sizes.
4094 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4096 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4097 its generated DWARF Call Frame Info. This encoding was causing GDB to
4098 panic, that panic has been fixed. Ref: gdb/1628.
4100 * Fixed a problem when examining parameters in shared library code.
4102 When examining parameters in optimized shared library code generated
4103 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4104 not available''. GDB now correctly displays the variable's value.
4106 *** Changes in GDB 6.1:
4108 * Removed --with-mmalloc
4110 Support for the mmalloc memory manager has been removed, as it
4111 conflicted with the internal gdb byte cache.
4113 * Changes in AMD64 configurations
4115 The AMD64 target now includes the %cs and %ss registers. As a result
4116 the AMD64 remote protocol has changed; this affects the floating-point
4117 and SSE registers. If you rely on those registers for your debugging,
4118 you should upgrade gdbserver on the remote side.
4120 * Revised SPARC target
4122 The SPARC target has been completely revised, incorporating the
4123 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4124 support for LynxOS and SunOS 4 has been dropped. Calling functions
4125 from within GDB on operating systems with a non-executable stack
4126 (Solaris, OpenBSD) now works.
4130 GDB has a new C++ demangler which does a better job on the mangled
4131 names generated by current versions of g++. It also runs faster, so
4132 with this and other changes gdb should now start faster on large C++
4135 * DWARF 2 Location Expressions
4137 GDB support for location expressions has been extended to support function
4138 arguments and frame bases. Older versions of GDB could crash when they
4141 * C++ nested types and namespaces
4143 GDB's support for nested types and namespaces in C++ has been
4144 improved, especially if you use the DWARF 2 debugging format. (This
4145 is the default for recent versions of GCC on most platforms.)
4146 Specifically, if you have a class "Inner" defined within a class or
4147 namespace "Outer", then GDB realizes that the class's name is
4148 "Outer::Inner", not simply "Inner". This should greatly reduce the
4149 frequency of complaints about not finding RTTI symbols. In addition,
4150 if you are stopped at inside of a function defined within a namespace,
4151 GDB modifies its name lookup accordingly.
4153 * New native configurations
4155 NetBSD/amd64 x86_64-*-netbsd*
4156 OpenBSD/amd64 x86_64-*-openbsd*
4157 OpenBSD/alpha alpha*-*-openbsd*
4158 OpenBSD/sparc sparc-*-openbsd*
4159 OpenBSD/sparc64 sparc64-*-openbsd*
4161 * New debugging protocols
4163 M32R with SDI protocol m32r-*-elf*
4165 * "set prompt-escape-char" command deleted.
4167 The command "set prompt-escape-char" has been deleted. This command,
4168 and its very obscure effet on GDB's prompt, was never documented,
4169 tested, nor mentioned in the NEWS file.
4171 * OBSOLETE configurations and files
4173 Configurations that have been declared obsolete in this release have
4174 been commented out. Unless there is activity to revive these
4175 configurations, the next release of GDB will have their sources
4176 permanently REMOVED.
4178 Sun 3, running SunOS 3 m68*-*-sunos3*
4179 Sun 3, running SunOS 4 m68*-*-sunos4*
4180 Sun 2, running SunOS 3 m68000-*-sunos3*
4181 Sun 2, running SunOS 4 m68000-*-sunos4*
4182 Motorola 680x0 running LynxOS m68*-*-lynxos*
4183 AT&T 3b1/Unix pc m68*-att-*
4184 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4185 decstation mips-dec-* mips-little-*
4186 riscos mips-*-riscos* mips-*-sysv*
4187 sonymips mips-sony-*
4188 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4190 * REMOVED configurations and files
4192 SGI Irix-4.x mips-sgi-irix4 or iris4
4193 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4194 Z8000 simulator z8k-zilog-none or z8ksim
4195 Matsushita MN10200 w/simulator mn10200-*-*
4196 H8/500 simulator h8500-hitachi-hms or h8500hms
4197 HP/PA running BSD hppa*-*-bsd*
4198 HP/PA running OSF/1 hppa*-*-osf*
4199 HP/PA Pro target hppa*-*-pro*
4200 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4201 386BSD i[3456]86-*-bsd*
4202 Sequent family i[3456]86-sequent-sysv4*
4203 i[3456]86-sequent-sysv*
4204 i[3456]86-sequent-bsd*
4205 SPARC running LynxOS sparc-*-lynxos*
4206 SPARC running SunOS 4 sparc-*-sunos4*
4207 Tsqware Sparclet sparclet-*-*
4208 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4210 *** Changes in GDB 6.0:
4214 Support for debugging the Objective-C programming language has been
4215 integrated into GDB.
4217 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4219 DWARF 2's Call Frame Information makes available compiler generated
4220 information that more exactly describes the program's run-time stack.
4221 By using this information, GDB is able to provide more robust stack
4224 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4225 have been updated to use a new backtrace mechanism which includes
4226 DWARF 2 CFI support.
4230 GDB's remote protocol has been extended to include support for hosted
4231 file I/O (where the remote target uses GDB's file system). See GDB's
4232 remote protocol documentation for details.
4234 * All targets using the new architecture framework.
4236 All of GDB's targets have been updated to use the new internal
4237 architecture framework. The way is now open for future GDB releases
4238 to include cross-architecture native debugging support (i386 on amd64,
4241 * GNU/Linux's Thread Local Storage (TLS)
4243 GDB now includes support for for the GNU/Linux implementation of
4244 per-thread variables.
4246 * GNU/Linux's Native POSIX Thread Library (NPTL)
4248 GDB's thread code has been updated to work with either the new
4249 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4251 * Separate debug info.
4253 GDB, in conjunction with BINUTILS, now supports a mechanism for
4254 automatically loading debug information from a separate file. Instead
4255 of shipping full debug and non-debug versions of system libraries,
4256 system integrators can now instead ship just the stripped libraries
4257 and optional debug files.
4259 * DWARF 2 Location Expressions
4261 DWARF 2 Location Expressions allow the compiler to more completely
4262 describe the location of variables (even in optimized code) to the
4265 GDB now includes preliminary support for location expressions (support
4266 for DW_OP_piece is still missing).
4270 A number of long standing bugs that caused GDB to die while starting a
4271 Java application have been fixed. GDB's Java support is now
4272 considered "useable".
4274 * GNU/Linux support for fork, vfork, and exec.
4276 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4277 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4280 * GDB supports logging output to a file
4282 There are two new commands, "set logging" and "show logging", which can be
4283 used to capture GDB's output to a file.
4285 * The meaning of "detach" has changed for gdbserver
4287 The "detach" command will now resume the application, as documented. To
4288 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4291 * d10v, m68hc11 `regs' command deprecated
4293 The `info registers' command has been updated so that it displays the
4294 registers using a format identical to the old `regs' command.
4298 A new command, "maint set profile on/off", has been added. This command can
4299 be used to enable or disable profiling while running GDB, to profile a
4300 session or a set of commands. In addition there is a new configure switch,
4301 "--enable-profiling", which will cause GDB to be compiled with profiling
4302 data, for more informative profiling results.
4304 * Default MI syntax changed to "mi2".
4306 The default MI (machine interface) syntax, enabled by the command line
4307 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4308 "mi1", can be enabled by specifying the option "-i=mi1".
4310 Support for the original "mi0" syntax (included in GDB 5.0) has been
4313 Fix for gdb/192: removed extraneous space when displaying frame level.
4314 Fix for gdb/672: update changelist is now output in mi list format.
4315 Fix for gdb/702: a -var-assign that updates the value now shows up
4316 in a subsequent -var-update.
4318 * New native configurations.
4320 FreeBSD/amd64 x86_64-*-freebsd*
4322 * Multi-arched targets.
4324 HP/PA HPUX11 hppa*-*-hpux*
4325 Renesas M32R/D w/simulator m32r-*-elf*
4327 * OBSOLETE configurations and files
4329 Configurations that have been declared obsolete in this release have
4330 been commented out. Unless there is activity to revive these
4331 configurations, the next release of GDB will have their sources
4332 permanently REMOVED.
4334 Z8000 simulator z8k-zilog-none or z8ksim
4335 Matsushita MN10200 w/simulator mn10200-*-*
4336 H8/500 simulator h8500-hitachi-hms or h8500hms
4337 HP/PA running BSD hppa*-*-bsd*
4338 HP/PA running OSF/1 hppa*-*-osf*
4339 HP/PA Pro target hppa*-*-pro*
4340 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4341 Sequent family i[3456]86-sequent-sysv4*
4342 i[3456]86-sequent-sysv*
4343 i[3456]86-sequent-bsd*
4344 Tsqware Sparclet sparclet-*-*
4345 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4347 * REMOVED configurations and files
4350 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4351 IBM AIX PS/2 i[3456]86-*-aix
4352 i386 running Mach 3.0 i[3456]86-*-mach3*
4353 i386 running Mach i[3456]86-*-mach*
4354 i386 running OSF/1 i[3456]86-*osf1mk*
4355 HP/Apollo 68k Family m68*-apollo*-sysv*,
4357 m68*-hp-bsd*, m68*-hp-hpux*
4358 Argonaut Risc Chip (ARC) arc-*-*
4359 Mitsubishi D30V d30v-*-*
4360 Fujitsu FR30 fr30-*-elf*
4361 OS/9000 i[34]86-*-os9k
4362 I960 with MON960 i960-*-coff
4364 * MIPS $fp behavior changed
4366 The convenience variable $fp, for the MIPS, now consistently returns
4367 the address of the current frame's base. Previously, depending on the
4368 context, $fp could refer to either $sp or the current frame's base
4369 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4370 The GNU Source-Level Debugger''.
4372 *** Changes in GDB 5.3:
4374 * GNU/Linux shared library multi-threaded performance improved.
4376 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4377 `/proc', in preference to `ptrace' for memory reads. This may result
4378 in an improvement in the start-up time of multi-threaded, shared
4379 library applications when run under GDB. One GDB user writes: ``loads
4380 shared libs like mad''.
4382 * ``gdbserver'' now supports multi-threaded applications on some targets
4384 Support for debugging multi-threaded applications which use
4385 the GNU/Linux LinuxThreads package has been added for
4386 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4387 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4389 * GDB now supports C/C++ preprocessor macros.
4391 GDB now expands preprocessor macro invocations in C/C++ expressions,
4392 and provides various commands for showing macro definitions and how
4395 The new command `macro expand EXPRESSION' expands any macro
4396 invocations in expression, and shows the result.
4398 The new command `show macro MACRO-NAME' shows the definition of the
4399 macro named MACRO-NAME, and where it was defined.
4401 Most compilers don't include information about macros in the debugging
4402 information by default. In GCC 3.1, for example, you need to compile
4403 your program with the options `-gdwarf-2 -g3'. If the macro
4404 information is present in the executable, GDB will read it.
4406 * Multi-arched targets.
4408 DEC Alpha (partial) alpha*-*-*
4409 DEC VAX (partial) vax-*-*
4411 National Semiconductor NS32000 (partial) ns32k-*-*
4412 Motorola 68000 (partial) m68k-*-*
4413 Motorola MCORE mcore-*-*
4417 Fujitsu FRV architecture added by Red Hat frv*-*-*
4420 * New native configurations
4422 Alpha NetBSD alpha*-*-netbsd*
4423 SH NetBSD sh*-*-netbsdelf*
4424 MIPS NetBSD mips*-*-netbsd*
4425 UltraSPARC NetBSD sparc64-*-netbsd*
4427 * OBSOLETE configurations and files
4429 Configurations that have been declared obsolete in this release have
4430 been commented out. Unless there is activity to revive these
4431 configurations, the next release of GDB will have their sources
4432 permanently REMOVED.
4434 Mitsubishi D30V d30v-*-*
4435 OS/9000 i[34]86-*-os9k
4436 IBM AIX PS/2 i[3456]86-*-aix
4437 Fujitsu FR30 fr30-*-elf*
4438 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4439 Argonaut Risc Chip (ARC) arc-*-*
4440 i386 running Mach 3.0 i[3456]86-*-mach3*
4441 i386 running Mach i[3456]86-*-mach*
4442 i386 running OSF/1 i[3456]86-*osf1mk*
4443 HP/Apollo 68k Family m68*-apollo*-sysv*,
4445 m68*-hp-bsd*, m68*-hp-hpux*
4446 I960 with MON960 i960-*-coff
4448 * OBSOLETE languages
4450 CHILL, a Pascal like language used by telecommunications companies.
4452 * REMOVED configurations and files
4454 AMD 29k family via UDI a29k-amd-udi, udi29k
4455 A29K VxWorks a29k-*-vxworks
4456 AMD 29000 embedded, using EBMON a29k-none-none
4457 AMD 29000 embedded with COFF a29k-none-coff
4458 AMD 29000 embedded with a.out a29k-none-aout
4460 testsuite/gdb.hp/gdb.threads-hp/ directory
4462 * New command "set max-user-call-depth <nnn>"
4464 This command allows the user to limit the call depth of user-defined
4465 commands. The default is 1024.
4467 * Changes in FreeBSD/i386 native debugging.
4469 Support for the "generate-core-file" has been added.
4471 * New commands "dump", "append", and "restore".
4473 These commands allow data to be copied from target memory
4474 to a bfd-format or binary file (dump and append), and back
4475 from a file into memory (restore).
4477 * Improved "next/step" support on multi-processor Alpha Tru64.
4479 The previous single-step mechanism could cause unpredictable problems,
4480 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4481 of a software single-step mechanism prevents this.
4483 *** Changes in GDB 5.2.1:
4491 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4492 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4493 Fix, by Joel Brobecker imported from mainline.
4495 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4496 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4497 Fix, by Fred Fish, imported from mainline.
4499 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4500 Surprisingly enough, it works now.
4501 By Michal Ludvig, imported from mainline.
4503 i386 hardware watchpoint support:
4504 avoid misses on second run for some targets.
4505 By Pierre Muller, imported from mainline.
4507 *** Changes in GDB 5.2:
4509 * New command "set trust-readonly-sections on[off]".
4511 This command is a hint that tells gdb that read-only sections
4512 really are read-only (ie. that their contents will not change).
4513 In this mode, gdb will go to the object file rather than the
4514 target to read memory from read-only sections (such as ".text").
4515 This can be a significant performance improvement on some
4516 (notably embedded) targets.
4518 * New command "generate-core-file" (or "gcore").
4520 This new gdb command allows the user to drop a core file of the child
4521 process state at any time. So far it's been implemented only for
4522 GNU/Linux and Solaris, but should be relatively easily ported to other
4523 hosts. Argument is core file name (defaults to core.<pid>).
4525 * New command line option
4527 GDB now accepts --pid or -p followed by a process id.
4529 * Change in command line behavior -- corefiles vs. process ids.
4531 There is a subtle behavior in the way in which GDB handles
4532 command line arguments. The first non-flag argument is always
4533 a program to debug, but the second non-flag argument may either
4534 be a corefile or a process id. Previously, GDB would attempt to
4535 open the second argument as a corefile, and if that failed, would
4536 issue a superfluous error message and then attempt to attach it as
4537 a process. Now, if the second argument begins with a non-digit,
4538 it will be treated as a corefile. If it begins with a digit,
4539 GDB will attempt to attach it as a process, and if no such process
4540 is found, will then attempt to open it as a corefile.
4542 * Changes in ARM configurations.
4544 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4545 configuration is fully multi-arch.
4547 * New native configurations
4549 ARM NetBSD arm*-*-netbsd*
4550 x86 OpenBSD i[3456]86-*-openbsd*
4551 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4552 Sparc64 running FreeBSD sparc64-*-freebsd*
4556 Sanyo XStormy16 xstormy16-elf
4558 * OBSOLETE configurations and files
4560 Configurations that have been declared obsolete in this release have
4561 been commented out. Unless there is activity to revive these
4562 configurations, the next release of GDB will have their sources
4563 permanently REMOVED.
4565 AMD 29k family via UDI a29k-amd-udi, udi29k
4566 A29K VxWorks a29k-*-vxworks
4567 AMD 29000 embedded, using EBMON a29k-none-none
4568 AMD 29000 embedded with COFF a29k-none-coff
4569 AMD 29000 embedded with a.out a29k-none-aout
4571 testsuite/gdb.hp/gdb.threads-hp/ directory
4573 * REMOVED configurations and files
4575 TI TMS320C80 tic80-*-*
4577 PowerPC Solaris powerpcle-*-solaris*
4578 PowerPC Windows NT powerpcle-*-cygwin32
4579 PowerPC Netware powerpc-*-netware*
4580 Harris/CXUX m88k m88*-harris-cxux*
4581 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4582 ns32k-utek-sysv* ns32k-utek-*
4583 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4584 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4585 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4586 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4587 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4589 * Changes to command line processing
4591 The new `--args' feature can be used to specify command-line arguments
4592 for the inferior from gdb's command line.
4594 * Changes to key bindings
4596 There is a new `operate-and-get-next' function bound to `C-o'.
4598 *** Changes in GDB 5.1.1
4600 Fix compile problem on DJGPP.
4602 Fix a problem with floating-point registers on the i386 being
4605 Fix to stop GDB crashing on .debug_str debug info.
4607 Numerous documentation fixes.
4609 Numerous testsuite fixes.
4611 *** Changes in GDB 5.1:
4613 * New native configurations
4615 Alpha FreeBSD alpha*-*-freebsd*
4616 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4617 MIPS GNU/Linux mips*-*-linux*
4618 MIPS SGI Irix 6.x mips*-sgi-irix6*
4619 ia64 AIX ia64-*-aix*
4620 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4624 Motorola 68HC11 and 68HC12 m68hc11-elf
4626 UltraSparc running GNU/Linux sparc64-*-linux*
4628 * OBSOLETE configurations and files
4630 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4631 Harris/CXUX m88k m88*-harris-cxux*
4632 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4633 ns32k-utek-sysv* ns32k-utek-*
4634 TI TMS320C80 tic80-*-*
4636 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4637 PowerPC Solaris powerpcle-*-solaris*
4638 PowerPC Windows NT powerpcle-*-cygwin32
4639 PowerPC Netware powerpc-*-netware*
4640 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4641 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4642 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4643 Apple Macintosh (MPW) host N/A
4645 stuff.c (Program to stuff files into a specially prepared space in kdb)
4646 kdb-start.c (Main loop for the standalone kernel debugger)
4648 Configurations that have been declared obsolete in this release have
4649 been commented out. Unless there is activity to revive these
4650 configurations, the next release of GDB will have their sources
4651 permanently REMOVED.
4653 * REMOVED configurations and files
4655 Altos 3068 m68*-altos-*
4656 Convex c1-*-*, c2-*-*
4658 ARM RISCix arm-*-* (as host)
4662 * GDB has been converted to ISO C.
4664 GDB's source code has been converted to ISO C. In particular, the
4665 sources are fully protoized, and rely on standard headers being
4670 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4672 * The MI enabled by default.
4674 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4675 revised and enabled by default. Packages which use GDB as a debugging
4676 engine behind a UI or another front end are encouraged to switch to
4677 using the GDB/MI interface, instead of the old annotations interface
4678 which is now deprecated.
4680 * Support for debugging Pascal programs.
4682 GDB now includes support for debugging Pascal programs. The following
4683 main features are supported:
4685 - Pascal-specific data types such as sets;
4687 - automatic recognition of Pascal sources based on file-name
4690 - Pascal-style display of data types, variables, and functions;
4692 - a Pascal expression parser.
4694 However, some important features are not yet supported.
4696 - Pascal string operations are not supported at all;
4698 - there are some problems with boolean types;
4700 - Pascal type hexadecimal constants are not supported
4701 because they conflict with the internal variables format;
4703 - support for Pascal objects and classes is not full yet;
4705 - unlike Pascal, GDB is case-sensitive for symbol names.
4707 * Changes in completion.
4709 Commands such as `shell', `run' and `set args', which pass arguments
4710 to inferior programs, now complete on file names, similar to what
4711 users expect at the shell prompt.
4713 Commands which accept locations, such as `disassemble', `print',
4714 `breakpoint', `until', etc. now complete on filenames as well as
4715 program symbols. Thus, if you type "break foob TAB", and the source
4716 files linked into the programs include `foobar.c', that file name will
4717 be one of the candidates for completion. However, file names are not
4718 considered for completion after you typed a colon that delimits a file
4719 name from a name of a function in that file, as in "break foo.c:bar".
4721 `set demangle-style' completes on available demangling styles.
4723 * New platform-independent commands:
4725 It is now possible to define a post-hook for a command as well as a
4726 hook that runs before the command. For more details, see the
4727 documentation of `hookpost' in the GDB manual.
4729 * Changes in GNU/Linux native debugging.
4731 Support for debugging multi-threaded programs has been completely
4732 revised for all platforms except m68k and sparc. You can now debug as
4733 many threads as your system allows you to have.
4735 Attach/detach is supported for multi-threaded programs.
4737 Support for SSE registers was added for x86. This doesn't work for
4738 multi-threaded programs though.
4740 * Changes in MIPS configurations.
4742 Multi-arch support is enabled for all MIPS configurations.
4744 GDB can now be built as native debugger on SGI Irix 6.x systems for
4745 debugging n32 executables. (Debugging 64-bit executables is not yet
4748 * Unified support for hardware watchpoints in all x86 configurations.
4750 Most (if not all) native x86 configurations support hardware-assisted
4751 breakpoints and watchpoints in a unified manner. This support
4752 implements debug register sharing between watchpoints, which allows to
4753 put a virtually infinite number of watchpoints on the same address,
4754 and also supports watching regions up to 16 bytes with several debug
4757 The new maintenance command `maintenance show-debug-regs' toggles
4758 debugging print-outs in functions that insert, remove, and test
4759 watchpoints and hardware breakpoints.
4761 * Changes in the DJGPP native configuration.
4763 New command ``info dos sysinfo'' displays assorted information about
4764 the CPU, OS, memory, and DPMI server.
4766 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4767 display information about segment descriptors stored in GDT, LDT, and
4770 New commands ``info dos pde'' and ``info dos pte'' display entries
4771 from Page Directory and Page Tables (for now works with CWSDPMI only).
4772 New command ``info dos address-pte'' displays the Page Table entry for
4773 a given linear address.
4775 GDB can now pass command lines longer than 126 characters to the
4776 program being debugged (requires an update to the libdbg.a library
4777 which is part of the DJGPP development kit).
4779 DWARF2 debug info is now supported.
4781 It is now possible to `step' and `next' through calls to `longjmp'.
4783 * Changes in documentation.
4785 All GDB documentation was converted to GFDL, the GNU Free
4786 Documentation License.
4788 Tracepoints-related commands are now fully documented in the GDB
4791 TUI, the Text-mode User Interface, is now documented in the manual.
4793 Tracepoints-related commands are now fully documented in the GDB
4796 The "GDB Internals" manual now has an index. It also includes
4797 documentation of `ui_out' functions, GDB coding standards, x86
4798 hardware watchpoints, and memory region attributes.
4800 * GDB's version number moved to ``version.in''
4802 The Makefile variable VERSION has been replaced by the file
4803 ``version.in''. People creating GDB distributions should update the
4804 contents of this file.
4808 GUD support is now a standard part of the EMACS distribution.
4810 *** Changes in GDB 5.0:
4812 * Improved support for debugging FP programs on x86 targets
4814 Unified and much-improved support for debugging floating-point
4815 programs on all x86 targets. In particular, ``info float'' now
4816 displays the FP registers in the same format on all x86 targets, with
4817 greater level of detail.
4819 * Improvements and bugfixes in hardware-assisted watchpoints
4821 It is now possible to watch array elements, struct members, and
4822 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4823 on x86 targets no longer erroneously trigger when the address is
4826 * Improvements in the native DJGPP version of GDB
4828 The distribution now includes all the scripts and auxiliary files
4829 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4830 machines ``out of the box''.
4832 The DJGPP version can now debug programs that use signals. It is
4833 possible to catch signals that happened in the debuggee, deliver
4834 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4835 would kill the program being debugged.) Programs that hook hardware
4836 interrupts (keyboard, timer, etc.) can also be debugged.
4838 It is now possible to debug DJGPP programs that redirect their
4839 standard handles or switch them to raw (as opposed to cooked) mode, or
4840 even close them. The command ``run < foo > bar'' works as expected,
4841 and ``info terminal'' reports useful information about the debuggee's
4842 terminal, including raw/cooked mode, redirection, etc.
4844 The DJGPP version now uses termios functions for console I/O, which
4845 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4848 DOS-style file names with drive letters are now fully supported by
4851 It is now possible to debug DJGPP programs that switch their working
4852 directory. It is also possible to rerun the debuggee any number of
4853 times without restarting GDB; thus, you can use the same setup,
4854 breakpoints, etc. for many debugging sessions.
4856 * New native configurations
4858 ARM GNU/Linux arm*-*-linux*
4859 PowerPC GNU/Linux powerpc-*-linux*
4863 Motorola MCore mcore-*-*
4864 x86 VxWorks i[3456]86-*-vxworks*
4865 PowerPC VxWorks powerpc-*-vxworks*
4866 TI TMS320C80 tic80-*-*
4868 * OBSOLETE configurations
4870 Altos 3068 m68*-altos-*
4871 Convex c1-*-*, c2-*-*
4873 ARM RISCix arm-*-* (as host)
4876 Configurations that have been declared obsolete will be commented out,
4877 but the code will be left in place. If there is no activity to revive
4878 these configurations before the next release of GDB, the sources will
4879 be permanently REMOVED.
4881 * Gould support removed
4883 Support for the Gould PowerNode and NP1 has been removed.
4885 * New features for SVR4
4887 On SVR4 native platforms (such as Solaris), if you attach to a process
4888 without first loading a symbol file, GDB will now attempt to locate and
4889 load symbols from the running process's executable file.
4891 * Many C++ enhancements
4893 C++ support has been greatly improved. Overload resolution now works properly
4894 in almost all cases. RTTI support is on the way.
4896 * Remote targets can connect to a sub-program
4898 A popen(3) style serial-device has been added. This device starts a
4899 sub-process (such as a stand-alone simulator) and then communicates
4900 with that. The sub-program to run is specified using the syntax
4901 ``|<program> <args>'' vis:
4903 (gdb) set remotedebug 1
4904 (gdb) target extended-remote |mn10300-elf-sim program-args
4906 * MIPS 64 remote protocol
4908 A long standing bug in the mips64 remote protocol where by GDB
4909 expected certain 32 bit registers (ex SR) to be transfered as 32
4910 instead of 64 bits has been fixed.
4912 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4913 added to provide backward compatibility with older versions of GDB.
4915 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4917 The command ``set remotebinarydownload'' command has been replaced by
4918 ``set remote X-packet''. Other commands in ``set remote'' family
4919 include ``set remote P-packet''.
4921 * Breakpoint commands accept ranges.
4923 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4924 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4925 ``tracepoint passcount'' also accepts a range of tracepoints.
4927 * ``apropos'' command added.
4929 The ``apropos'' command searches through command names and
4930 documentation strings, printing out matches, making it much easier to
4931 try to find a command that does what you are looking for.
4935 A new machine oriented interface (MI) has been added to GDB. This
4936 interface is designed for debug environments running GDB as a separate
4937 process. This is part of the long term libGDB project. See the
4938 "GDB/MI" chapter of the GDB manual for further information. It can be
4939 enabled by configuring with:
4941 .../configure --enable-gdbmi
4943 *** Changes in GDB-4.18:
4945 * New native configurations
4947 HP-UX 10.20 hppa*-*-hpux10.20
4948 HP-UX 11.x hppa*-*-hpux11.0*
4949 M68K GNU/Linux m68*-*-linux*
4953 Fujitsu FR30 fr30-*-elf*
4954 Intel StrongARM strongarm-*-*
4955 Mitsubishi D30V d30v-*-*
4957 * OBSOLETE configurations
4959 Gould PowerNode, NP1 np1-*-*, pn-*-*
4961 Configurations that have been declared obsolete will be commented out,
4962 but the code will be left in place. If there is no activity to revive
4963 these configurations before the next release of GDB, the sources will
4964 be permanently REMOVED.
4968 As a compatibility experiment, GDB's source files buildsym.h and
4969 buildsym.c have been converted to pure standard C, no longer
4970 containing any K&R compatibility code. We believe that all systems in
4971 use today either come with a standard C compiler, or have a GCC port
4972 available. If this is not true, please report the affected
4973 configuration to bug-gdb@gnu.org immediately. See the README file for
4974 information about getting a standard C compiler if you don't have one
4979 GDB now uses readline 2.2.
4981 * set extension-language
4983 You can now control the mapping between filename extensions and source
4984 languages by using the `set extension-language' command. For instance,
4985 you can ask GDB to treat .c files as C++ by saying
4986 set extension-language .c c++
4987 The command `info extensions' lists all of the recognized extensions
4988 and their associated languages.
4990 * Setting processor type for PowerPC and RS/6000
4992 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4993 you can use the `set processor' command to specify what variant of the
4994 PowerPC family you are debugging. The command
4998 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4999 following PowerPC and RS6000 variants:
5001 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5002 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5004 403GC IBM PowerPC 403GC
5005 505 Motorola PowerPC 505
5006 860 Motorola PowerPC 860 or 850
5007 601 Motorola PowerPC 601
5008 602 Motorola PowerPC 602
5009 603 Motorola/IBM PowerPC 603 or 603e
5010 604 Motorola PowerPC 604 or 604e
5011 750 Motorola/IBM PowerPC 750 or 750
5013 At the moment, this command just tells GDB what to name the
5014 special-purpose processor registers. Since almost all the affected
5015 registers are inaccessible to user-level programs, this command is
5016 only useful for remote debugging in its present form.
5020 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5021 more extensive support for HP-UX. Added features include shared
5022 library support, kernel threads and hardware watchpoints for 11.00,
5023 support for HP's ANSI C and C++ compilers, and a compatibility mode
5024 for xdb and dbx commands.
5028 HP's donation includes the new concept of catchpoints, which is a
5029 generalization of the old catch command. On HP-UX, it is now possible
5030 to catch exec, fork, and vfork, as well as library loading.
5032 This means that the existing catch command has changed; its first
5033 argument now specifies the type of catch to be set up. See the
5034 output of "help catch" for a list of catchpoint types.
5036 * Debugging across forks
5038 On HP-UX, you can choose which process to debug when a fork() happens
5043 HP has donated a curses-based terminal user interface (TUI). To get
5044 it, build with --enable-tui. Although this can be enabled for any
5045 configuration, at present it only works for native HP debugging.
5047 * GDB remote protocol additions
5049 A new protocol packet 'X' that writes binary data is now available.
5050 Default behavior is to try 'X', then drop back to 'M' if the stub
5051 fails to respond. The settable variable `remotebinarydownload'
5052 allows explicit control over the use of 'X'.
5054 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5055 full 64-bit address. The command
5057 set remoteaddresssize 32
5059 can be used to revert to the old behaviour. For existing remote stubs
5060 the change should not be noticed, as the additional address information
5063 In order to assist in debugging stubs, you may use the maintenance
5064 command `packet' to send any text string to the stub. For instance,
5066 maint packet heythere
5068 sends the packet "$heythere#<checksum>". Note that it is very easy to
5069 disrupt a debugging session by sending the wrong packet at the wrong
5072 The compare-sections command allows you to compare section data on the
5073 target to what is in the executable file without uploading or
5074 downloading, by comparing CRC checksums.
5076 * Tracing can collect general expressions
5078 You may now collect general expressions at tracepoints. This requires
5079 further additions to the target-side stub; see tracepoint.c and
5080 doc/agentexpr.texi for further details.
5082 * mask-address variable for Mips
5084 For Mips targets, you may control the zeroing of the upper 32 bits of
5085 a 64-bit address by entering `set mask-address on'. This is mainly
5086 of interest to users of embedded R4xxx and R5xxx processors.
5088 * Higher serial baud rates
5090 GDB's serial code now allows you to specify baud rates 57600, 115200,
5091 230400, and 460800 baud. (Note that your host system may not be able
5092 to achieve all of these rates.)
5096 The i960 configuration now includes an initial implementation of a
5097 builtin simulator, contributed by Jim Wilson.
5100 *** Changes in GDB-4.17:
5102 * New native configurations
5104 Alpha GNU/Linux alpha*-*-linux*
5105 Unixware 2.x i[3456]86-unixware2*
5106 Irix 6.x mips*-sgi-irix6*
5107 PowerPC GNU/Linux powerpc-*-linux*
5108 PowerPC Solaris powerpcle-*-solaris*
5109 Sparc GNU/Linux sparc-*-linux*
5110 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5114 Argonaut Risc Chip (ARC) arc-*-*
5115 Hitachi H8/300S h8300*-*-*
5116 Matsushita MN10200 w/simulator mn10200-*-*
5117 Matsushita MN10300 w/simulator mn10300-*-*
5118 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5119 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5120 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5121 Mitsubishi D10V w/simulator d10v-*-*
5122 Mitsubishi M32R/D w/simulator m32r-*-elf*
5123 Tsqware Sparclet sparclet-*-*
5124 NEC V850 w/simulator v850-*-*
5126 * New debugging protocols
5128 ARM with RDI protocol arm*-*-*
5129 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5130 DDB and LSI variants of PMON protocol mips*-*-*
5131 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5132 PowerPC with SDS protocol powerpc{,le}-*-eabi
5133 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5137 All configurations can now understand and use the DWARF 2 debugging
5138 format. The choice is automatic, if the symbol file contains DWARF 2
5143 GDB now includes basic Java language support. This support is
5144 only useful with Java compilers that produce native machine code.
5146 * solib-absolute-prefix and solib-search-path
5148 For SunOS and SVR4 shared libraries, you may now set the prefix for
5149 loading absolute shared library symbol files, and the search path for
5150 locating non-absolute shared library symbol files.
5152 * Live range splitting
5154 GDB can now effectively debug code for which GCC has performed live
5155 range splitting as part of its optimization. See gdb/doc/LRS for
5156 more details on the expected format of the stabs information.
5160 GDB's support for the GNU Hurd, including thread debugging, has been
5161 updated to work with current versions of the Hurd.
5165 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5166 instruction set. ARM GDB automatically detects when Thumb
5167 instructions are in use, and adjusts disassembly and backtracing
5172 GDB's MIPS target configurations now handle the MIP16 16-bit
5177 GDB now includes support for overlays; if an executable has been
5178 linked such that multiple sections are based at the same address, GDB
5179 will decide which section to use for symbolic info. You can choose to
5180 control the decision manually, using overlay commands, or implement
5181 additional target-side support and use "overlay load-target" to bring
5182 in the overlay mapping. Do "help overlay" for more detail.
5186 The command "info symbol <address>" displays information about
5187 the symbol at the specified address.
5191 The standard remote protocol now includes an extension that allows
5192 asynchronous collection and display of trace data. This requires
5193 extensive support in the target-side debugging stub. Tracing mode
5194 includes a new interaction mode in GDB and new commands: see the
5195 file tracepoint.c for more details.
5199 Configurations for embedded MIPS now include a simulator contributed
5200 by Cygnus Solutions. The simulator supports the instruction sets
5201 of most MIPS variants.
5205 Sparc configurations may now include the ERC32 simulator contributed
5206 by the European Space Agency. The simulator is not built into
5207 Sparc targets by default; configure with --enable-sim to include it.
5211 For target configurations that may include multiple variants of a
5212 basic architecture (such as MIPS and SH), you may now set the
5213 architecture explicitly. "set arch" sets, "info arch" lists
5214 the possible architectures.
5216 *** Changes in GDB-4.16:
5218 * New native configurations
5220 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5221 M68K NetBSD m68k-*-netbsd*
5222 PowerPC AIX 4.x powerpc-*-aix*
5223 PowerPC MacOS powerpc-*-macos*
5224 PowerPC Windows NT powerpcle-*-cygwin32
5225 RS/6000 AIX 4.x rs6000-*-aix4*
5229 ARM with RDP protocol arm-*-*
5230 I960 with MON960 i960-*-coff
5231 MIPS VxWorks mips*-*-vxworks*
5232 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5233 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5235 Matra Sparclet sparclet-*-*
5239 The powerpc-eabi configuration now includes the PSIM simulator,
5240 contributed by Andrew Cagney, with assistance from Mike Meissner.
5241 PSIM is a very elaborate model of the PowerPC, including not only
5242 basic instruction set execution, but also details of execution unit
5243 performance and I/O hardware. See sim/ppc/README for more details.
5247 GDB now works with Solaris 2.5.
5249 * Windows 95/NT native
5251 GDB will now work as a native debugger on Windows 95 and Windows NT.
5252 To build it from source, you must use the "gnu-win32" environment,
5253 which uses a DLL to emulate enough of Unix to run the GNU tools.
5254 Further information, binaries, and sources are available at
5255 ftp.cygnus.com, under pub/gnu-win32.
5257 * dont-repeat command
5259 If a user-defined command includes the command `dont-repeat', then the
5260 command will not be repeated if the user just types return. This is
5261 useful if the command is time-consuming to run, so that accidental
5262 extra keystrokes don't run the same command many times.
5264 * Send break instead of ^C
5266 The standard remote protocol now includes an option to send a break
5267 rather than a ^C to the target in order to interrupt it. By default,
5268 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5270 * Remote protocol timeout
5272 The standard remote protocol includes a new variable `remotetimeout'
5273 that allows you to set the number of seconds before GDB gives up trying
5274 to read from the target. The default value is 2.
5276 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5278 By default GDB will automatically keep track of objects as they are
5279 loaded and unloaded by the dynamic linker. By using the command `set
5280 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5281 when shared library events occur, thus allowing you to set breakpoints
5282 in shared libraries which are explicitly loaded by the inferior.
5284 Note this feature does not work on hpux8. On hpux9 you must link
5285 /usr/lib/end.o into your program. This feature should work
5286 automatically on hpux10.
5288 * Irix 5.x hardware watchpoint support
5290 Irix 5 configurations now support the use of hardware watchpoints.
5292 * Mips protocol "SYN garbage limit"
5294 When debugging a Mips target using the `target mips' protocol, you
5295 may set the number of characters that GDB will ignore by setting
5296 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5297 every character. The default value is 1050.
5299 * Recording and replaying remote debug sessions
5301 If you set `remotelogfile' to the name of a file, gdb will write to it
5302 a recording of a remote debug session. This recording may then be
5303 replayed back to gdb using "gdbreplay". See gdbserver/README for
5304 details. This is useful when you have a problem with GDB while doing
5305 remote debugging; you can make a recording of the session and send it
5306 to someone else, who can then recreate the problem.
5308 * Speedups for remote debugging
5310 GDB includes speedups for downloading and stepping MIPS systems using
5311 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5312 and more efficient S-record downloading.
5314 * Memory use reductions and statistics collection
5316 GDB now uses less memory and reports statistics about memory usage.
5317 Try the `maint print statistics' command, for example.
5319 *** Changes in GDB-4.15:
5321 * Psymtabs for XCOFF
5323 The symbol reader for AIX GDB now uses partial symbol tables. This
5324 can greatly improve startup time, especially for large executables.
5326 * Remote targets use caching
5328 Remote targets now use a data cache to speed up communication with the
5329 remote side. The data cache could lead to incorrect results because
5330 it doesn't know about volatile variables, thus making it impossible to
5331 debug targets which use memory mapped I/O devices. `set remotecache
5332 off' turns the the data cache off.
5334 * Remote targets may have threads
5336 The standard remote protocol now includes support for multiple threads
5337 in the target system, using new protocol commands 'H' and 'T'. See
5338 gdb/remote.c for details.
5342 If GDB is configured with `--enable-netrom', then it will include
5343 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5344 acts as though it is a bank of ROM on the target board, but you can
5345 write into it over the network. GDB's support consists only of
5346 support for fast loading into the emulated ROM; to debug, you must use
5347 another protocol, such as standard remote protocol. The usual
5348 sequence is something like
5350 target nrom <netrom-hostname>
5352 target remote <netrom-hostname>:1235
5356 GDB now includes support for the Apple Macintosh, as a host only. It
5357 may be run as either an MPW tool or as a standalone application, and
5358 it can debug through the serial port. All the usual GDB commands are
5359 available, but to the target command, you must supply "serial" as the
5360 device type instead of "/dev/ttyXX". See mpw-README in the main
5361 directory for more information on how to build. The MPW configuration
5362 scripts */mpw-config.in support only a few targets, and only the
5363 mips-idt-ecoff target has been tested.
5367 GDB configuration now uses autoconf. This is not user-visible,
5368 but does simplify configuration and building.
5372 GDB now supports hpux10.
5374 *** Changes in GDB-4.14:
5376 * New native configurations
5378 x86 FreeBSD i[345]86-*-freebsd
5379 x86 NetBSD i[345]86-*-netbsd
5380 NS32k NetBSD ns32k-*-netbsd
5381 Sparc NetBSD sparc-*-netbsd
5385 A29K VxWorks a29k-*-vxworks
5386 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5387 CPU32 EST-300 emulator m68*-*-est*
5388 PowerPC ELF powerpc-*-elf
5391 * Alpha OSF/1 support for procfs
5393 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5394 possible to attach to running processes. As the mounting of the /proc
5395 filesystem is optional on the Alpha, GDB automatically determines
5396 the availability of /proc during startup. This can lead to problems
5397 if /proc is unmounted after GDB has been started.
5399 * Arguments to user-defined commands
5401 User commands may accept up to 10 arguments separated by whitespace.
5402 Arguments are accessed within the user command via $arg0..$arg9. A
5405 print $arg0 + $arg1 + $arg2
5407 To execute the command use:
5410 Defines the command "adder" which prints the sum of its three arguments.
5411 Note the arguments are text substitutions, so they may reference variables,
5412 use complex expressions, or even perform inferior function calls.
5414 * New `if' and `while' commands
5416 This makes it possible to write more sophisticated user-defined
5417 commands. Both commands take a single argument, which is the
5418 expression to evaluate, and must be followed by the commands to
5419 execute, one per line, if the expression is nonzero, the list being
5420 terminated by the word `end'. The `if' command list may include an
5421 `else' word, which causes the following commands to be executed only
5422 if the expression is zero.
5424 * Fortran source language mode
5426 GDB now includes partial support for Fortran 77. It will recognize
5427 Fortran programs and can evaluate a subset of Fortran expressions, but
5428 variables and functions may not be handled correctly. GDB will work
5429 with G77, but does not yet know much about symbols emitted by other
5432 * Better HPUX support
5434 Most debugging facilities now work on dynamic executables for HPPAs
5435 running hpux9 or later. You can attach to running dynamically linked
5436 processes, but by default the dynamic libraries will be read-only, so
5437 for instance you won't be able to put breakpoints in them. To change
5438 that behavior do the following before running the program:
5444 This will cause the libraries to be mapped private and read-write.
5445 To revert to the normal behavior, do this:
5451 You cannot set breakpoints or examine data in the library until after
5452 the library is loaded if the function/data symbols do not have
5455 GDB can now also read debug symbols produced by the HP C compiler on
5456 HPPAs (sorry, no C++, Fortran or 68k support).
5458 * Target byte order now dynamically selectable
5460 You can choose which byte order to use with a target system, via the
5461 commands "set endian big" and "set endian little", and you can see the
5462 current setting by using "show endian". You can also give the command
5463 "set endian auto", in which case GDB will use the byte order
5464 associated with the executable. Currently, only embedded MIPS
5465 configurations support dynamic selection of target byte order.
5467 * New DOS host serial code
5469 This version uses DPMI interrupts to handle buffered I/O, so you
5470 no longer need to run asynctsr when debugging boards connected to
5473 *** Changes in GDB-4.13:
5475 * New "complete" command
5477 This lists all the possible completions for the rest of the line, if it
5478 were to be given as a command itself. This is intended for use by emacs.
5480 * Trailing space optional in prompt
5482 "set prompt" no longer adds a space for you after the prompt you set. This
5483 allows you to set a prompt which ends in a space or one that does not.
5485 * Breakpoint hit counts
5487 "info break" now displays a count of the number of times the breakpoint
5488 has been hit. This is especially useful in conjunction with "ignore"; you
5489 can ignore a large number of breakpoint hits, look at the breakpoint info
5490 to see how many times the breakpoint was hit, then run again, ignoring one
5491 less than that number, and this will get you quickly to the last hit of
5494 * Ability to stop printing at NULL character
5496 "set print null-stop" will cause GDB to stop printing the characters of
5497 an array when the first NULL is encountered. This is useful when large
5498 arrays actually contain only short strings.
5500 * Shared library breakpoints
5502 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5503 breakpoints in shared libraries before the executable is run.
5505 * Hardware watchpoints
5507 There is a new hardware breakpoint for the watch command for sparclite
5508 targets. See gdb/sparclite/hw_breakpoint.note.
5510 Hardware watchpoints are also now supported under GNU/Linux.
5514 Annotations have been added. These are for use with graphical interfaces,
5515 and are still experimental. Currently only gdba.el uses these.
5517 * Improved Irix 5 support
5519 GDB now works properly with Irix 5.2.
5521 * Improved HPPA support
5523 GDB now works properly with the latest GCC and GAS.
5525 * New native configurations
5527 Sequent PTX4 i[34]86-sequent-ptx4
5528 HPPA running OSF/1 hppa*-*-osf*
5529 Atari TT running SVR4 m68*-*-sysv4*
5530 RS/6000 LynxOS rs6000-*-lynxos*
5534 OS/9000 i[34]86-*-os9k
5535 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5538 * Hitachi SH7000 and E7000-PC ICE support
5540 There is now support for communicating with the Hitachi E7000-PC ICE.
5541 This is available automatically when GDB is configured for the SH.
5545 As usual, a variety of small fixes and improvements, both generic
5546 and configuration-specific. See the ChangeLog for more detail.
5548 *** Changes in GDB-4.12:
5550 * Irix 5 is now supported
5554 GDB-4.12 on the HPPA has a number of changes which make it unable
5555 to debug the output from the currently released versions of GCC and
5556 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5557 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5558 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5561 *** Changes in GDB-4.11:
5563 * User visible changes:
5567 The "set remotedebug" option is now consistent between the mips remote
5568 target, remote targets using the gdb-specific protocol, UDI (AMD's
5569 debug protocol for the 29k) and the 88k bug monitor. It is now an
5570 integer specifying a debug level (normally 0 or 1, but 2 means more
5571 debugging info for the mips target).
5573 * DEC Alpha native support
5575 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5576 debug info, but GDB works fairly well with the DEC compiler and should
5577 work with a future GCC release. See the README file for a few
5578 Alpha-specific notes.
5580 * Preliminary thread implementation
5582 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5584 * LynxOS native and target support for 386
5586 This release has been hosted on LynxOS 2.2, and also can be configured
5587 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5590 * Improvements in C++ mangling/demangling.
5592 This release has much better g++ debugging, specifically in name
5593 mangling/demangling, virtual function calls, print virtual table,
5594 call methods, ...etc.
5596 *** Changes in GDB-4.10:
5598 * User visible changes:
5600 Remote debugging using the GDB-specific (`target remote') protocol now
5601 supports the `load' command. This is only useful if you have some
5602 other way of getting the stub to the target system, and you can put it
5603 somewhere in memory where it won't get clobbered by the download.
5605 Filename completion now works.
5607 When run under emacs mode, the "info line" command now causes the
5608 arrow to point to the line specified. Also, "info line" prints
5609 addresses in symbolic form (as well as hex).
5611 All vxworks based targets now support a user settable option, called
5612 vxworks-timeout. This option represents the number of seconds gdb
5613 should wait for responses to rpc's. You might want to use this if
5614 your vxworks target is, perhaps, a slow software simulator or happens
5615 to be on the far side of a thin network line.
5619 This release contains support for using a DEC alpha as a GDB host for
5620 cross debugging. Native alpha debugging is not supported yet.
5623 *** Changes in GDB-4.9:
5627 This is the first GDB release which is accompanied by a matching testsuite.
5628 The testsuite requires installation of dejagnu, which should be available
5629 via ftp from most sites that carry GNU software.
5633 'Cfront' style demangling has had its name changed to 'ARM' style, to
5634 emphasize that it was written from the specifications in the C++ Annotated
5635 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5636 disclaimers, it still generated too much confusion with users attempting to
5637 use gdb with AT&T cfront.
5641 GDB now uses a standard remote interface to a simulator library.
5642 So far, the library contains simulators for the Zilog Z8001/2, the
5643 Hitachi H8/300, H8/500 and Super-H.
5645 * New targets supported
5647 H8/300 simulator h8300-hitachi-hms or h8300hms
5648 H8/500 simulator h8500-hitachi-hms or h8500hms
5649 SH simulator sh-hitachi-hms or sh
5650 Z8000 simulator z8k-zilog-none or z8ksim
5651 IDT MIPS board over serial line mips-idt-ecoff
5653 Cross-debugging to GO32 targets is supported. It requires a custom
5654 version of the i386-stub.c module which is integrated with the
5655 GO32 memory extender.
5657 * New remote protocols
5659 MIPS remote debugging protocol.
5661 * New source languages supported
5663 This version includes preliminary support for Chill, a Pascal like language
5664 used by telecommunications companies. Chill support is also being integrated
5665 into the GNU compiler, but we don't know when it will be publically available.
5668 *** Changes in GDB-4.8:
5670 * HP Precision Architecture supported
5672 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5673 version of this support was available as a set of patches from the
5674 University of Utah. GDB does not support debugging of programs
5675 compiled with the HP compiler, because HP will not document their file
5676 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5677 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5679 Many problems in the preliminary version have been fixed.
5681 * Faster and better demangling
5683 We have improved template demangling and fixed numerous bugs in the GNU style
5684 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5685 character types (wchar_t) are now supported. Demangling of each symbol is now
5686 only done once, and is cached when the symbol table for a file is read in.
5687 This results in a small increase in memory usage for C programs, a moderate
5688 increase in memory usage for C++ programs, and a fantastic speedup in
5691 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5692 from the specifications in the Annotated Reference Manual, which AT&T's
5693 compiler does not actually implement.
5695 * G++ multiple inheritance compiler problem
5697 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5698 inheritance lattices was reworked to properly discover ambiguities. We
5699 recently found an example which causes this new algorithm to fail in a
5700 very subtle way, producing bad debug information for those classes.
5701 The file 'gcc.patch' (in this directory) can be applied to gcc to
5702 circumvent the problem. A future GCC release will contain a complete
5705 The previous G++ debug info problem (mentioned below for the gdb-4.7
5706 release) is fixed in gcc version 2.3.2.
5708 * Improved configure script
5710 The `configure' script will now attempt to guess your system type if
5711 you don't supply a host system type. The old scheme of supplying a
5712 host system triplet is preferable over using this. All the magic is
5713 done in the new `config.guess' script. Examine it for details.
5715 We have also brought our configure script much more in line with the FSF's
5716 version. It now supports the --with-xxx options. In particular,
5717 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5718 The resulting GDB will not be able to read arbitrary object file formats --
5719 only the format ``expected'' to be used on the configured target system.
5720 We hope to make this the default in a future release.
5722 * Documentation improvements
5724 There's new internal documentation on how to modify GDB, and how to
5725 produce clean changes to the code. We implore people to read it
5726 before submitting changes.
5728 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5729 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5730 `info' files are also provided. To build `info' files from scratch,
5731 you will need the latest `makeinfo' release, which will be available in
5732 a future texinfo-X.Y release.
5734 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5735 We're not sure exactly which versions have this problem, but it has
5736 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5737 or better. If that isn't possible, there is a patch in
5738 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5739 around this problem.
5743 GDB now supports array constants that can be used in expressions typed in by
5744 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5745 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5748 The new directory `gdb/sparclite' contains a program that demonstrates
5749 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5751 * New native hosts supported
5753 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5754 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5756 * New targets supported
5758 AMD 29k family via UDI a29k-amd-udi or udi29k
5760 * New file formats supported
5762 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5763 HPUX core files, and SCO 3.2v2 core files.
5767 Attaching to processes now works again; thanks for the many bug reports.
5769 We have also stomped on a bunch of core dumps caused by
5770 printf_filtered("%s") problems.
5772 We eliminated a copyright problem on the rpc and ptrace header files
5773 for VxWorks, which was discovered at the last minute during the 4.7
5774 release. You should now be able to build a VxWorks GDB.
5776 You can now interrupt gdb while an attached process is running. This
5777 will cause the attached process to stop, and give control back to GDB.
5779 We fixed problems caused by using too many file descriptors
5780 for reading symbols from object files and libraries. This was
5781 especially a problem for programs that used many (~100) shared
5784 The `step' command now only enters a subroutine if there is line number
5785 information for the subroutine. Otherwise it acts like the `next'
5786 command. Previously, `step' would enter subroutines if there was
5787 any debugging information about the routine. This avoids problems
5788 when using `cc -g1' on MIPS machines.
5790 * Internal improvements
5792 GDB's internal interfaces have been improved to make it easier to support
5793 debugging of multiple languages in the future.
5795 GDB now uses a common structure for symbol information internally.
5796 Minimal symbols (derived from linkage symbols in object files), partial
5797 symbols (from a quick scan of debug information), and full symbols
5798 contain a common subset of information, making it easier to write
5799 shared code that handles any of them.
5801 * New command line options
5803 We now accept --silent as an alias for --quiet.
5807 The memory-mapped-malloc library is now licensed under the GNU Library
5808 General Public License.
5810 *** Changes in GDB-4.7:
5812 * Host/native/target split
5814 GDB has had some major internal surgery to untangle the support for
5815 hosts and remote targets. Now, when you configure GDB for a remote
5816 target, it will no longer load in all of the support for debugging
5817 local programs on the host. When fully completed and tested, this will
5818 ensure that arbitrary host/target combinations are possible.
5820 The primary conceptual shift is to separate the non-portable code in
5821 GDB into three categories. Host specific code is required any time GDB
5822 is compiled on that host, regardless of the target. Target specific
5823 code relates to the peculiarities of the target, but can be compiled on
5824 any host. Native specific code is everything else: it can only be
5825 built when the host and target are the same system. Child process
5826 handling and core file support are two common `native' examples.
5828 GDB's use of /proc for controlling Unix child processes is now cleaner.
5829 It has been split out into a single module under the `target_ops' vector,
5830 plus two native-dependent functions for each system that uses /proc.
5832 * New hosts supported
5834 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5835 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5836 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5838 * New targets supported
5840 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5841 68030 and CPU32 m68030-*-*, m68332-*-*
5843 * New native hosts supported
5845 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5846 (386bsd is not well tested yet)
5847 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5849 * New file formats supported
5851 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5852 supports reading of `a.out.adobe' object files, which are an a.out
5853 format extended with minimal information about multiple sections.
5857 `show copying' is the same as the old `info copying'.
5858 `show warranty' is the same as `info warrantee'.
5859 These were renamed for consistency. The old commands continue to work.
5861 `info handle' is a new alias for `info signals'.
5863 You can now define pre-command hooks, which attach arbitrary command
5864 scripts to any command. The commands in the hook will be executed
5865 prior to the user's command. You can also create a hook which will be
5866 executed whenever the program stops. See gdb.texinfo.
5870 We now deal with Cfront style name mangling, and can even extract type
5871 info from mangled symbols. GDB can automatically figure out which
5872 symbol mangling style your C++ compiler uses.
5874 Calling of methods and virtual functions has been improved as well.
5878 The crash that occured when debugging Sun Ansi-C compiled binaries is
5879 fixed. This was due to mishandling of the extra N_SO stabs output
5882 We also finally got Ultrix 4.2 running in house, and fixed core file
5883 support, with help from a dozen people on the net.
5885 John M. Farrell discovered that the reason that single-stepping was so
5886 slow on all of the Mips based platforms (primarily SGI and DEC) was
5887 that we were trying to demangle and lookup a symbol used for internal
5888 purposes on every instruction that was being stepped through. Changing
5889 the name of that symbol so that it couldn't be mistaken for a C++
5890 mangled symbol sped things up a great deal.
5892 Rich Pixley sped up symbol lookups in general by getting much smarter
5893 about when C++ symbol mangling is necessary. This should make symbol
5894 completion (TAB on the command line) much faster. It's not as fast as
5895 we'd like, but it's significantly faster than gdb-4.6.
5899 A new user controllable variable 'call_scratch_address' can
5900 specify the location of a scratch area to be used when GDB
5901 calls a function in the target. This is necessary because the
5902 usual method of putting the scratch area on the stack does not work
5903 in systems that have separate instruction and data spaces.
5905 We integrated changes to support the 29k UDI (Universal Debugger
5906 Interface), but discovered at the last minute that we didn't have all
5907 of the appropriate copyright paperwork. We are working with AMD to
5908 resolve this, and hope to have it available soon.
5912 We have sped up the remote serial line protocol, especially for targets
5913 with lots of registers. It now supports a new `expedited status' ('T')
5914 message which can be used in place of the existing 'S' status message.
5915 This allows the remote stub to send only the registers that GDB
5916 needs to make a quick decision about single-stepping or conditional
5917 breakpoints, eliminating the need to fetch the entire register set for
5918 each instruction being stepped through.
5920 The GDB remote serial protocol now implements a write-through cache for
5921 registers, only re-reading the registers if the target has run.
5923 There is also a new remote serial stub for SPARC processors. You can
5924 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5925 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5926 processor with a serial port.
5930 Configure.in files have become much easier to read and modify. A new
5931 `table driven' format makes it more obvious what configurations are
5932 supported, and what files each one uses.
5936 There is a new opcodes library which will eventually contain all of the
5937 disassembly routines and opcode tables. At present, it only contains
5938 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5939 disassembler (binutils/objdump) to share these routines.
5941 The libiberty library is now copylefted under the GNU Library General
5942 Public License. This allows more liberal use, and was done so libg++
5943 can use it. This makes no difference to GDB, since the Library License
5944 grants all the rights from the General Public License.
5948 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5949 reference to the stabs symbol info used by the debugger. It is (as far
5950 as we know) the only published document on this fascinating topic. We
5951 encourage you to read it, compare it to the stabs information on your
5952 system, and send improvements on the document in general (to
5953 bug-gdb@prep.ai.mit.edu).
5955 And, of course, many bugs have been fixed.
5958 *** Changes in GDB-4.6:
5960 * Better support for C++ function names
5962 GDB now accepts as input the "demangled form" of C++ overloaded function
5963 names and member function names, and can do command completion on such names
5964 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5965 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5966 Make use of command completion, it is your friend.
5968 GDB also now accepts a variety of C++ mangled symbol formats. They are
5969 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5970 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5971 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5972 for the list of formats.
5974 * G++ symbol mangling problem
5976 Recent versions of gcc have a bug in how they emit debugging information for
5977 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5978 directory) can be applied to gcc to fix the problem. Alternatively, if you
5979 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5980 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5981 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5984 * New 'maintenance' command
5986 All of the commands related to hacking GDB internals have been moved out of
5987 the main command set, and now live behind the 'maintenance' command. This
5988 can also be abbreviated as 'mt'. The following changes were made:
5990 dump-me -> maintenance dump-me
5991 info all-breakpoints -> maintenance info breakpoints
5992 printmsyms -> maintenance print msyms
5993 printobjfiles -> maintenance print objfiles
5994 printpsyms -> maintenance print psymbols
5995 printsyms -> maintenance print symbols
5997 The following commands are new:
5999 maintenance demangle Call internal GDB demangler routine to
6000 demangle a C++ link name and prints the result.
6001 maintenance print type Print a type chain for a given symbol
6003 * Change to .gdbinit file processing
6005 We now read the $HOME/.gdbinit file before processing the argv arguments
6006 (e.g. reading symbol files or core files). This allows global parameters to
6007 be set, which will apply during the symbol reading. The ./.gdbinit is still
6008 read after argv processing.
6010 * New hosts supported
6012 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6014 GNU/Linux support i386-unknown-linux or linux
6016 We are also including code to support the HP/PA running BSD and HPUX. This
6017 is almost guaranteed not to work, as we didn't have time to test or build it
6018 for this release. We are including it so that the more adventurous (or
6019 masochistic) of you can play with it. We also had major problems with the
6020 fact that the compiler that we got from HP doesn't support the -g option.
6023 * New targets supported
6025 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6027 * More smarts about finding #include files
6029 GDB now remembers the compilation directory for all include files, and for
6030 all files from which C is generated (like yacc and lex sources). This
6031 greatly improves GDB's ability to find yacc/lex sources, and include files,
6032 especially if you are debugging your program from a directory different from
6033 the one that contains your sources.
6035 We also fixed a bug which caused difficulty with listing and setting
6036 breakpoints in include files which contain C code. (In the past, you had to
6037 try twice in order to list an include file that you hadn't looked at before.)
6039 * Interesting infernals change
6041 GDB now deals with arbitrary numbers of sections, where the symbols for each
6042 section must be relocated relative to that section's landing place in the
6043 target's address space. This work was needed to support ELF with embedded
6044 stabs used by Solaris-2.0.
6046 * Bug fixes (of course!)
6048 There have been loads of fixes for the following things:
6049 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6050 i960, stabs, DOS(GO32), procfs, etc...
6052 See the ChangeLog for details.
6054 *** Changes in GDB-4.5:
6056 * New machines supported (host and target)
6058 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6060 SGI Irix-4.x mips-sgi-irix4 or iris4
6062 * New malloc package
6064 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6065 Mmalloc is capable of handling mutiple heaps of memory. It is also
6066 capable of saving a heap to a file, and then mapping it back in later.
6067 This can be used to greatly speedup the startup of GDB by using a
6068 pre-parsed symbol table which lives in a mmalloc managed heap. For
6069 more details, please read mmalloc/mmalloc.texi.
6073 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6074 'help info proc' for details.
6076 * MIPS ecoff symbol table format
6078 The code that reads MIPS symbol table format is now supported on all hosts.
6079 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6082 * File name changes for MS-DOS
6084 Many files in the config directories have been renamed to make it easier to
6085 support GDB on MS-DOSe systems (which have very restrictive file name
6086 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6087 environment) is close to working but has some remaining problems. Note
6088 that debugging of DOS programs is not supported, due to limitations
6089 in the ``operating system'', but it can be used to host cross-debugging.
6091 * Cross byte order fixes
6093 Many fixes have been made to support cross debugging of Sparc and MIPS
6094 targets from hosts whose byte order differs.
6096 * New -mapped and -readnow options
6098 If memory-mapped files are available on your system through the 'mmap'
6099 system call, you can use the -mapped option on the `file' or
6100 `symbol-file' commands to cause GDB to write the symbols from your
6101 program into a reusable file. If the program you are debugging is
6102 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6103 Future GDB debugging sessions will notice the presence of this file,
6104 and will quickly map in symbol information from it, rather than reading
6105 the symbol table from the executable program. Using the '-mapped'
6106 option in a GDB `file' or `symbol-file' command has the same effect as
6107 starting GDB with the '-mapped' command-line option.
6109 You can cause GDB to read the entire symbol table immediately by using
6110 the '-readnow' option with any of the commands that load symbol table
6111 information (or on the GDB command line). This makes the command
6112 slower, but makes future operations faster.
6114 The -mapped and -readnow options are typically combined in order to
6115 build a `fred.syms' file that contains complete symbol information.
6116 A simple GDB invocation to do nothing but build a `.syms' file for future
6119 gdb -batch -nx -mapped -readnow programname
6121 The `.syms' file is specific to the host machine on which GDB is run.
6122 It holds an exact image of GDB's internal symbol table. It cannot be
6123 shared across multiple host platforms.
6125 * longjmp() handling
6127 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6128 siglongjmp() without losing control. This feature has not yet been ported to
6129 all systems. It currently works on many 386 platforms, all MIPS-based
6130 platforms (SGI, DECstation, etc), and Sun3/4.
6134 Preliminary work has been put in to support the new Solaris OS from Sun. At
6135 this time, it can control and debug processes, but it is not capable of
6140 As always, many many bug fixes. The major areas were with g++, and mipsread.
6141 People using the MIPS-based platforms should experience fewer mysterious
6142 crashes and trashed symbol tables.
6144 *** Changes in GDB-4.4:
6146 * New machines supported (host and target)
6148 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6150 BSD Reno on Vax vax-dec-bsd
6151 Ultrix on Vax vax-dec-ultrix
6153 * New machines supported (target)
6155 AMD 29000 embedded, using EBMON a29k-none-none
6159 GDB continues to improve its handling of C++. `References' work better.
6160 The demangler has also been improved, and now deals with symbols mangled as
6161 per the Annotated C++ Reference Guide.
6163 GDB also now handles `stabs' symbol information embedded in MIPS
6164 `ecoff' symbol tables. Since the ecoff format was not easily
6165 extensible to handle new languages such as C++, this appeared to be a
6166 good way to put C++ debugging info into MIPS binaries. This option
6167 will be supported in the GNU C compiler, version 2, when it is
6170 * New features for SVR4
6172 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6173 shared libraries. Debugging dynamically linked programs should present
6174 only minor differences from debugging statically linked programs.
6176 The `info proc' command will print out information about any process
6177 on an SVR4 system (including the one you are debugging). At the moment,
6178 it prints the address mappings of the process.
6180 If you bring up GDB on another SVR4 system, please send mail to
6181 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6183 * Better dynamic linking support in SunOS
6185 Reading symbols from shared libraries which contain debugging symbols
6186 now works properly. However, there remain issues such as automatic
6187 skipping of `transfer vector' code during function calls, which
6188 make it harder to debug code in a shared library, than to debug the
6189 same code linked statically.
6193 GDB is now using the latest `getopt' routines from the FSF. This
6194 version accepts the -- prefix for options with long names. GDB will
6195 continue to accept the old forms (-option and +option) as well.
6196 Various single letter abbreviations for options have been explicity
6197 added to the option table so that they won't get overshadowed in the
6198 future by other options that begin with the same letter.
6202 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6203 Many assorted bugs have been handled. Many more remain to be handled.
6204 See the various ChangeLog files (primarily in gdb and bfd) for details.
6207 *** Changes in GDB-4.3:
6209 * New machines supported (host and target)
6211 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6212 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6213 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6215 * Almost SCO Unix support
6217 We had hoped to support:
6218 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6219 (except for core file support), but we discovered very late in the release
6220 that it has problems with process groups that render gdb unusable. Sorry
6221 about that. I encourage people to fix it and post the fixes.
6223 * Preliminary ELF and DWARF support
6225 GDB can read ELF object files on System V Release 4, and can handle
6226 debugging records for C, in DWARF format, in ELF files. This support
6227 is preliminary. If you bring up GDB on another SVR4 system, please
6228 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6233 GDB now uses the latest `readline' library. One user-visible change
6234 is that two tabs will list possible command completions, which previously
6235 required typing M-? (meta-question mark, or ESC ?).
6239 The `stepi' bug that many of you noticed has been squashed.
6240 Many bugs in C++ have been handled. Many more remain to be handled.
6241 See the various ChangeLog files (primarily in gdb and bfd) for details.
6243 * State of the MIPS world (in case you wondered):
6245 GDB can understand the symbol tables emitted by the compilers
6246 supplied by most vendors of MIPS-based machines, including DEC. These
6247 symbol tables are in a format that essentially nobody else uses.
6249 Some versions of gcc come with an assembler post-processor called
6250 mips-tfile. This program is required if you want to do source-level
6251 debugging of gcc-compiled programs. I believe FSF does not ship
6252 mips-tfile with gcc version 1, but it will eventually come with gcc
6255 Debugging of g++ output remains a problem. g++ version 1.xx does not
6256 really support it at all. (If you're lucky, you should be able to get
6257 line numbers and stack traces to work, but no parameters or local
6258 variables.) With some work it should be possible to improve the
6261 When gcc version 2 is released, you will have somewhat better luck.
6262 However, even then you will get confusing results for inheritance and
6265 We will eventually provide full debugging of g++ output on
6266 DECstations. This will probably involve some kind of stabs-in-ecoff
6267 encapulation, but the details have not been worked out yet.
6270 *** Changes in GDB-4.2:
6272 * Improved configuration
6274 Only one copy of `configure' exists now, and it is not self-modifying.
6275 Porting BFD is simpler.
6279 The `step' and `next' commands now only stop at the first instruction
6280 of a source line. This prevents the multiple stops that used to occur
6281 in switch statements, for-loops, etc. `Step' continues to stop if a
6282 function that has debugging information is called within the line.
6286 Lots of small bugs fixed. More remain.
6288 * New host supported (not target)
6290 Intel 386 PC clone running Mach i386-none-mach
6293 *** Changes in GDB-4.1:
6295 * Multiple source language support
6297 GDB now has internal scaffolding to handle several source languages.
6298 It determines the type of each source file from its filename extension,
6299 and will switch expression parsing and number formatting to match the
6300 language of the function in the currently selected stack frame.
6301 You can also specifically set the language to be used, with
6302 `set language c' or `set language modula-2'.
6306 GDB now has preliminary support for the GNU Modula-2 compiler,
6307 currently under development at the State University of New York at
6308 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6309 continue through the fall of 1991 and into 1992.
6311 Other Modula-2 compilers are currently not supported, and attempting to
6312 debug programs compiled with them will likely result in an error as the
6313 symbol table is read. Feel free to work on it, though!
6315 There are hooks in GDB for strict type checking and range checking,
6316 in the `Modula-2 philosophy', but they do not currently work.
6320 GDB can now write to executable and core files (e.g. patch
6321 a variable's value). You must turn this switch on, specify
6322 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6323 by assigning a new value to a variable. Modifications take
6326 * Automatic SunOS shared library reading
6328 When you run your program, GDB automatically determines where its
6329 shared libraries (if any) have been loaded, and reads their symbols.
6330 The `share' command is no longer needed. This also works when
6331 examining core files.
6335 You can specify the number of lines that the `list' command shows.
6338 * New machines supported (host and target)
6340 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6341 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6342 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6344 * New hosts supported (not targets)
6346 IBM RT/PC: romp-ibm-aix or rtpc
6348 * New targets supported (not hosts)
6350 AMD 29000 embedded with COFF a29k-none-coff
6351 AMD 29000 embedded with a.out a29k-none-aout
6352 Ultracomputer remote kernel debug a29k-nyu-kern
6354 * New remote interfaces
6360 *** Changes in GDB-4.0:
6364 Wide output is wrapped at good places to make the output more readable.
6366 Gdb now supports cross-debugging from a host machine of one type to a
6367 target machine of another type. Communication with the target system
6368 is over serial lines. The ``target'' command handles connecting to the
6369 remote system; the ``load'' command will download a program into the
6370 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6371 also supports debugging of realtime processes running under VxWorks,
6372 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6373 stub on the target system.
6375 New CPUs supported include the AMD 29000 and Intel 960.
6377 GDB now reads object files and symbol tables via a ``binary file''
6378 library, which allows a single copy of GDB to debug programs of multiple
6379 object file types such as a.out and coff.
6381 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6382 refcard.dvi and refcard.ps are available to format it).
6385 * Control-Variable user interface simplified
6387 All variables that control the operation of the debugger can be set
6388 by the ``set'' command, and displayed by the ``show'' command.
6390 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6391 ``Show prompt'' produces the response:
6392 Gdb's prompt is new-gdb=>.
6394 What follows are the NEW set commands. The command ``help set'' will
6395 print a complete list of old and new set commands. ``help set FOO''
6396 will give a longer description of the variable FOO. ``show'' will show
6397 all of the variable descriptions and their current settings.
6399 confirm on/off: Enables warning questions for operations that are
6400 hard to recover from, e.g. rerunning the program while
6401 it is already running. Default is ON.
6403 editing on/off: Enables EMACS style command line editing
6404 of input. Previous lines can be recalled with
6405 control-P, the current line can be edited with control-B,
6406 you can search for commands with control-R, etc.
6409 history filename NAME: NAME is where the gdb command history
6410 will be stored. The default is .gdb_history,
6411 or the value of the environment variable
6414 history size N: The size, in commands, of the command history. The
6415 default is 256, or the value of the environment variable
6418 history save on/off: If this value is set to ON, the history file will
6419 be saved after exiting gdb. If set to OFF, the
6420 file will not be saved. The default is OFF.
6422 history expansion on/off: If this value is set to ON, then csh-like
6423 history expansion will be performed on
6424 command line input. The default is OFF.
6426 radix N: Sets the default radix for input and output. It can be set
6427 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6428 in the current radix, so "set radix 10" is always a no-op.
6430 height N: This integer value is the number of lines on a page. Default
6431 is 24, the current `stty rows'' setting, or the ``li#''
6432 setting from the termcap entry matching the environment
6435 width N: This integer value is the number of characters on a line.
6436 Default is 80, the current `stty cols'' setting, or the ``co#''
6437 setting from the termcap entry matching the environment
6440 Note: ``set screensize'' is obsolete. Use ``set height'' and
6441 ``set width'' instead.
6443 print address on/off: Print memory addresses in various command displays,
6444 such as stack traces and structure values. Gdb looks
6445 more ``symbolic'' if you turn this off; it looks more
6446 ``machine level'' with it on. Default is ON.
6448 print array on/off: Prettyprint arrays. New convenient format! Default
6451 print demangle on/off: Print C++ symbols in "source" form if on,
6454 print asm-demangle on/off: Same, for assembler level printouts
6457 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6460 * Support for Epoch Environment.
6462 The epoch environment is a version of Emacs v18 with windowing. One
6463 new command, ``inspect'', is identical to ``print'', except that if you
6464 are running in the epoch environment, the value is printed in its own
6468 * Support for Shared Libraries
6470 GDB can now debug programs and core files that use SunOS shared libraries.
6471 Symbols from a shared library cannot be referenced
6472 before the shared library has been linked with the program (this
6473 happens after you type ``run'' and before the function main() is entered).
6474 At any time after this linking (including when examining core files
6475 from dynamically linked programs), gdb reads the symbols from each
6476 shared library when you type the ``sharedlibrary'' command.
6477 It can be abbreviated ``share''.
6479 sharedlibrary REGEXP: Load shared object library symbols for files
6480 matching a unix regular expression. No argument
6481 indicates to load symbols for all shared libraries.
6483 info sharedlibrary: Status of loaded shared libraries.
6488 A watchpoint stops execution of a program whenever the value of an
6489 expression changes. Checking for this slows down execution
6490 tremendously whenever you are in the scope of the expression, but is
6491 quite useful for catching tough ``bit-spreader'' or pointer misuse
6492 problems. Some machines such as the 386 have hardware for doing this
6493 more quickly, and future versions of gdb will use this hardware.
6495 watch EXP: Set a watchpoint (breakpoint) for an expression.
6497 info watchpoints: Information about your watchpoints.
6499 delete N: Deletes watchpoint number N (same as breakpoints).
6500 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6501 enable N: Re-enables watchpoint number N (same as breakpoints).
6504 * C++ multiple inheritance
6506 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6509 * C++ exception handling
6511 Gdb now supports limited C++ exception handling. Besides the existing
6512 ability to breakpoint on an exception handler, gdb can breakpoint on
6513 the raising of an exception (before the stack is peeled back to the
6516 catch FOO: If there is a FOO exception handler in the dynamic scope,
6517 set a breakpoint to catch exceptions which may be raised there.
6518 Multiple exceptions (``catch foo bar baz'') may be caught.
6520 info catch: Lists all exceptions which may be caught in the
6521 current stack frame.
6524 * Minor command changes
6526 The command ``call func (arg, arg, ...)'' now acts like the print
6527 command, except it does not print or save a value if the function's result
6528 is void. This is similar to dbx usage.
6530 The ``up'' and ``down'' commands now always print the frame they end up
6531 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6532 frames without printing.
6534 * New directory command
6536 'dir' now adds directories to the FRONT of the source search path.
6537 The path starts off empty. Source files that contain debug information
6538 about the directory in which they were compiled can be found even
6539 with an empty path; Sun CC and GCC include this information. If GDB can't
6540 find your source file in the current directory, type "dir .".
6542 * Configuring GDB for compilation
6544 For normal use, type ``./configure host''. See README or gdb.texinfo
6547 GDB now handles cross debugging. If you are remotely debugging between
6548 two different machines, type ``./configure host -target=targ''.
6549 Host is the machine where GDB will run; targ is the machine
6550 where the program that you are debugging will run.
projects / external / binutils.git / blob