1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 8.0
6 * On Unix systems, GDBserver now does globbing expansion and variable
7 substitution in inferior command line arguments.
9 This is done by starting inferiors using a shell, like GDB does.
10 See "set startup-with-shell" in the user manual for how to disable
11 this from GDB when using "target extended-remote". When using
12 "target remote", you can disable the startup with shell by using the
13 new "--no-startup-with-shell" GDBserver command line option.
18 Indicates whether the inferior must be started with a shell or not.
22 set debug separate-debug-file
23 show debug separate-debug-file
24 Control the display of debug output about separate debug file search.
26 *** Changes in GDB 8.0
28 * GDB now supports access to the PKU register on GNU/Linux. The register is
29 added by the Memory Protection Keys for Userspace feature which will be
30 available in future Intel CPUs.
32 * GDB now supports C++11 rvalue references.
36 ** New functions to start, stop and access a running btrace recording.
37 ** Rvalue references are now supported in gdb.Type.
39 * GDB now supports recording and replaying rdrand and rdseed Intel 64
42 * Building GDB and GDBserver now requires a C++11 compiler.
44 For example, GCC 4.8 or later.
46 It is no longer possible to build GDB or GDBserver with a C
47 compiler. The --disable-build-with-cxx configure option has been
50 * Building GDB and GDBserver now requires GNU make >= 3.81.
52 It is no longer supported to build GDB or GDBserver with another
53 implementation of the make program or an earlier version of GNU make.
55 * Native debugging on MS-Windows supports command-line redirection
57 Command-line arguments used for starting programs on MS-Windows can
58 now include redirection symbols supported by native Windows shells,
59 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
60 as "run", "start", and "set args", as well as the corresponding MI
63 * Support for thread names on MS-Windows.
65 GDB now catches and handles the special exception that programs
66 running on MS-Windows use to assign names to threads in the
69 * Support for Java programs compiled with gcj has been removed.
71 * User commands now accept an unlimited number of arguments.
72 Previously, only up to 10 was accepted.
74 * The "eval" command now expands user-defined command arguments.
76 This makes it easier to process a variable number of arguments:
81 eval "print $arg%d", $i
86 * Target descriptions can now describe registers for sparc32 and sparc64.
88 * GDB now supports DWARF version 5 (debug information format).
89 Its .debug_names index is not yet supported.
91 * New native configurations
93 FreeBSD/mips mips*-*-freebsd
97 Synopsys ARC arc*-*-elf32
98 FreeBSD/mips mips*-*-freebsd
100 * Removed targets and native configurations
102 Alpha running FreeBSD alpha*-*-freebsd*
103 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
108 Erases all the flash memory regions reported by the target.
110 maint print arc arc-instruction address
111 Print internal disassembler information about instruction at a given address.
115 set disassembler-options
116 show disassembler-options
117 Controls the passing of target specific information to the disassembler.
118 If it is necessary to specify more than one disassembler option then
119 multiple options can be placed together into a comma separated list.
120 The default value is the empty string. Currently, the only supported
121 targets are ARM, PowerPC and S/390.
126 Erases all the flash memory regions reported by the target. This is
127 equivalent to the CLI command flash-erase.
129 -file-list-shared-libraries
130 List the shared libraries in the program. This is
131 equivalent to the CLI command "info shared".
133 *** Changes in GDB 7.12
135 * GDB and GDBserver now build with a C++ compiler by default.
137 The --enable-build-with-cxx configure option is now enabled by
138 default. One must now explicitly configure with
139 --disable-build-with-cxx in order to build with a C compiler. This
140 option will be removed in a future release.
142 * GDBserver now supports recording btrace without maintaining an active
145 * GDB now supports a negative repeat count in the 'x' command to examine
146 memory backward from the given address. For example:
149 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
150 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
151 (gdb) x/-5i 0x0000000000400580
152 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
153 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
154 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
155 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
156 0x40057b <main(int, char**)+25>:
157 callq 0x400536 <Func1(int, char const*)>
159 * Fortran: Support structures with fields of dynamic types and
160 arrays of dynamic types.
162 * The symbol dumping maintenance commands have new syntax.
163 maint print symbols [-pc address] [--] [filename]
164 maint print symbols [-objfile objfile] [-source source] [--] [filename]
165 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
166 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
167 maint print msymbols [-objfile objfile] [--] [filename]
169 * GDB now supports multibit bitfields and enums in target register
172 * New Python-based convenience function $_as_string(val), which returns
173 the textual representation of a value. This function is especially
174 useful to obtain the text label of an enum value.
176 * Intel MPX bound violation handling.
178 Segmentation faults caused by a Intel MPX boundary violation
179 now display the kind of violation (upper or lower), the memory
180 address accessed and the memory bounds, along with the usual
181 signal received and code location.
185 Program received signal SIGSEGV, Segmentation fault
186 Upper bound violation while accessing address 0x7fffffffc3b3
187 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
188 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
190 * Rust language support.
191 GDB now supports debugging programs written in the Rust programming
192 language. See https://www.rust-lang.org/ for more information about
195 * Support for running interpreters on specified input/output devices
197 GDB now supports a new mechanism that allows frontends to provide
198 fully featured GDB console views, as a better alternative to
199 building such views on top of the "-interpreter-exec console"
200 command. See the new "new-ui" command below. With that command,
201 frontends can now start GDB in the traditional command-line mode
202 running in an embedded terminal emulator widget, and create a
203 separate MI interpreter running on a specified i/o device. In this
204 way, GDB handles line editing, history, tab completion, etc. in the
205 console all by itself, and the GUI uses the separate MI interpreter
206 for its own control and synchronization, invisible to the command
209 * The "catch syscall" command catches groups of related syscalls.
211 The "catch syscall" command now supports catching a group of related
212 syscalls using the 'group:' or 'g:' prefix.
217 skip -gfile file-glob-pattern
218 skip -function function
219 skip -rfunction regular-expression
220 A generalized form of the skip command, with new support for
221 glob-style file names and regular expressions for function names.
222 Additionally, a file spec and a function spec may now be combined.
224 maint info line-table REGEXP
225 Display the contents of GDB's internal line table data struture.
228 Run any GDB unit tests that were compiled in.
231 Start a new user interface instance running INTERP as interpreter,
232 using the TTY file for input/output.
236 ** gdb.Breakpoint objects have a new attribute "pending", which
237 indicates whether the breakpoint is pending.
238 ** Three new breakpoint-related events have been added:
239 gdb.breakpoint_created, gdb.breakpoint_modified, and
240 gdb.breakpoint_deleted.
243 Signal ("set") the given MS-Windows event object. This is used in
244 conjunction with the Windows JIT debugging (AeDebug) support, where
245 the OS suspends a crashing process until a debugger can attach to
246 it. Resuming the crashing process, in order to debug it, is done by
249 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
250 was added in GDBserver, including JIT compiling fast tracepoint's
251 conditional expression bytecode into native code.
253 * Support for various remote target protocols and ROM monitors has
256 target m32rsdi Remote M32R debugging over SDI
257 target mips MIPS remote debugging protocol
258 target pmon PMON ROM monitor
259 target ddb NEC's DDB variant of PMON for Vr4300
260 target rockhopper NEC RockHopper variant of PMON
261 target lsi LSI variant of PMO
263 * Support for tracepoints and fast tracepoints on powerpc-linux,
264 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
265 including JIT compiling fast tracepoint's conditional expression
266 bytecode into native code.
268 * MI async record =record-started now includes the method and format used for
269 recording. For example:
271 =record-started,thread-group="i1",method="btrace",format="bts"
273 * MI async record =thread-selected now includes the frame field. For example:
275 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
279 Andes NDS32 nds32*-*-elf
281 *** Changes in GDB 7.11
283 * GDB now supports debugging kernel-based threads on FreeBSD.
285 * Per-inferior thread numbers
287 Thread numbers are now per inferior instead of global. If you're
288 debugging multiple inferiors, GDB displays thread IDs using a
289 qualified INF_NUM.THR_NUM form. For example:
293 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
294 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
295 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
296 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
298 As consequence, thread numbers as visible in the $_thread
299 convenience variable and in Python's InferiorThread.num attribute
300 are no longer unique between inferiors.
302 GDB now maintains a second thread ID per thread, referred to as the
303 global thread ID, which is the new equivalent of thread numbers in
304 previous releases. See also $_gthread below.
306 For backwards compatibility, MI's thread IDs always refer to global
309 * Commands that accept thread IDs now accept the qualified
310 INF_NUM.THR_NUM form as well. For example:
313 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
316 * In commands that accept a list of thread IDs, you can now refer to
317 all threads of an inferior using a star wildcard. GDB accepts
318 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
319 refer to all threads of the current inferior. For example, "info
322 * You can use "info threads -gid" to display the global thread ID of
325 * The new convenience variable $_gthread holds the global number of
328 * The new convenience variable $_inferior holds the number of the
331 * GDB now displays the ID and name of the thread that hit a breakpoint
332 or received a signal, if your program is multi-threaded. For
335 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
336 Thread 1 "main" received signal SIGINT, Interrupt.
338 * Record btrace now supports non-stop mode.
340 * Support for tracepoints on aarch64-linux was added in GDBserver.
342 * The 'record instruction-history' command now indicates speculative execution
343 when using the Intel Processor Trace recording format.
345 * GDB now allows users to specify explicit locations, bypassing
346 the linespec parser. This feature is also available to GDB/MI
349 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
350 GDB now is able to debug both AArch64 applications and ARM applications
353 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
354 including JIT compiling fast tracepoint's conditional expression bytecode
357 * GDB now supports displaced stepping on AArch64 GNU/Linux.
359 * "info threads", "info inferiors", "info display", "info checkpoints"
360 and "maint info program-spaces" now list the corresponding items in
361 ascending ID order, for consistency with all other "info" commands.
363 * In Ada, the overloads selection menu has been enhanced to display the
364 parameter types and the return types for the matching overloaded subprograms.
368 maint set target-non-stop (on|off|auto)
369 maint show target-non-stop
370 Control whether GDB targets always operate in non-stop mode even if
371 "set non-stop" is "off". The default is "auto", meaning non-stop
372 mode is enabled if supported by the target.
374 maint set bfd-sharing
375 maint show bfd-sharing
376 Control the reuse of bfd objects.
380 Control display of debugging info regarding bfd caching.
384 Control display of debugging info regarding FreeBSD threads.
386 set remote multiprocess-extensions-packet
387 show remote multiprocess-extensions-packet
388 Set/show the use of the remote protocol multiprocess extensions.
390 set remote thread-events
391 show remote thread-events
392 Set/show the use of thread create/exit events.
394 set ada print-signatures on|off
395 show ada print-signatures"
396 Control whether parameter types and return types are displayed in overloads
397 selection menus. It is activaled (@code{on}) by default.
401 Controls the maximum size of memory, in bytes, that GDB will
402 allocate for value contents. Prevents incorrect programs from
403 causing GDB to allocate overly large buffers. Default is 64k.
405 * The "disassemble" command accepts a new modifier: /s.
406 It prints mixed source+disassembly like /m with two differences:
407 - disassembled instructions are now printed in program order, and
408 - and source for all relevant files is now printed.
409 The "/m" option is now considered deprecated: its "source-centric"
410 output hasn't proved useful in practice.
412 * The "record instruction-history" command accepts a new modifier: /s.
413 It behaves exactly like /m and prints mixed source+disassembly.
415 * The "set scheduler-locking" command supports a new mode "replay".
416 It behaves like "off" in record mode and like "on" in replay mode.
418 * Support for various ROM monitors has been removed:
420 target dbug dBUG ROM monitor for Motorola ColdFire
421 target picobug Motorola picobug monitor
422 target dink32 DINK32 ROM monitor for PowerPC
423 target m32r Renesas M32R/D ROM monitor
424 target mon2000 mon2000 ROM monitor
425 target ppcbug PPCBUG ROM monitor for PowerPC
427 * Support for reading/writing memory and extracting values on architectures
428 whose memory is addressable in units of any integral multiple of 8 bits.
433 Indicates whether the inferior must be started with a shell or not.
436 Indicates that an exec system call was executed.
438 exec-events feature in qSupported
439 The qSupported packet allows GDB to request support for exec
440 events using the new 'gdbfeature' exec-event, and the qSupported
441 response can contain the corresponding 'stubfeature'. Set and
442 show commands can be used to display whether these features are enabled.
445 Equivalent to interrupting with the ^C character, but works in
448 thread created stop reason (T05 create:...)
449 Indicates that the thread was just created and is stopped at entry.
451 thread exit stop reply (w exitcode;tid)
452 Indicates that the thread has terminated.
455 Enables/disables thread create and exit event reporting. For
456 example, this is used in non-stop mode when GDB stops a set of
457 threads and synchronously waits for the their corresponding stop
458 replies. Without exit events, if one of the threads exits, GDB
459 would hang forever not knowing that it should no longer expect a
460 stop for that same thread.
463 Indicates that there are no resumed threads left in the target (all
464 threads are stopped). The remote stub reports support for this stop
465 reply to GDB's qSupported query.
468 Enables/disables catching syscalls from the inferior process.
469 The remote stub reports support for this packet to GDB's qSupported query.
471 syscall_entry stop reason
472 Indicates that a syscall was just called.
474 syscall_return stop reason
475 Indicates that a syscall just returned.
477 * Extended-remote exec events
479 ** GDB now has support for exec events on extended-remote Linux targets.
480 For such targets with Linux kernels 2.5.46 and later, this enables
481 follow-exec-mode and exec catchpoints.
483 set remote exec-event-feature-packet
484 show remote exec-event-feature-packet
485 Set/show the use of the remote exec event feature.
487 * Thread names in remote protocol
489 The reply to qXfer:threads:read may now include a name attribute for each
492 * Target remote mode fork and exec events
494 ** GDB now has support for fork and exec events on target remote mode
495 Linux targets. For such targets with Linux kernels 2.5.46 and later,
496 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
497 fork and exec catchpoints.
499 * Remote syscall events
501 ** GDB now has support for catch syscall on remote Linux targets,
502 currently enabled on x86/x86_64 architectures.
504 set remote catch-syscall-packet
505 show remote catch-syscall-packet
506 Set/show the use of the remote catch syscall feature.
510 ** The -var-set-format command now accepts the zero-hexadecimal
511 format. It outputs data in hexadecimal format with zero-padding on the
516 ** gdb.InferiorThread objects have a new attribute "global_num",
517 which refers to the thread's global thread ID. The existing
518 "num" attribute now refers to the thread's per-inferior number.
519 See "Per-inferior thread numbers" above.
520 ** gdb.InferiorThread objects have a new attribute "inferior", which
521 is the Inferior object the thread belongs to.
523 *** Changes in GDB 7.10
525 * Support for process record-replay and reverse debugging on aarch64*-linux*
526 targets has been added. GDB now supports recording of A64 instruction set
527 including advance SIMD instructions.
529 * Support for Sun's version of the "stabs" debug file format has been removed.
531 * GDB now honors the content of the file /proc/PID/coredump_filter
532 (PID is the process ID) on GNU/Linux systems. This file can be used
533 to specify the types of memory mappings that will be included in a
534 corefile. For more information, please refer to the manual page of
535 "core(5)". GDB also has a new command: "set use-coredump-filter
536 on|off". It allows to set whether GDB will read the content of the
537 /proc/PID/coredump_filter file when generating a corefile.
539 * The "info os" command on GNU/Linux can now display information on
541 "info os cpus" Listing of all cpus/cores on the system
543 * GDB has two new commands: "set serial parity odd|even|none" and
544 "show serial parity". These allows to set or show parity for the
547 * The "info source" command now displays the producer string if it was
548 present in the debug info. This typically includes the compiler version
549 and may include things like its command line arguments.
551 * The "info dll", an alias of the "info sharedlibrary" command,
552 is now available on all platforms.
554 * Directory names supplied to the "set sysroot" commands may be
555 prefixed with "target:" to tell GDB to access shared libraries from
556 the target system, be it local or remote. This replaces the prefix
557 "remote:". The default sysroot has been changed from "" to
558 "target:". "remote:" is automatically converted to "target:" for
559 backward compatibility.
561 * The system root specified by "set sysroot" will be prepended to the
562 filename of the main executable (if reported to GDB as absolute by
563 the operating system) when starting processes remotely, and when
564 attaching to already-running local or remote processes.
566 * GDB now supports automatic location and retrieval of executable
567 files from remote targets. Remote debugging can now be initiated
568 using only a "target remote" or "target extended-remote" command
569 (no "set sysroot" or "file" commands are required). See "New remote
572 * The "dump" command now supports verilog hex format.
574 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
576 * On GNU/Linux, GDB and gdbserver are now able to access executable
577 and shared library files without a "set sysroot" command when
578 attaching to processes running in different mount namespaces from
579 the debugger. This makes it possible to attach to processes in
580 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
581 See "New remote packets" below.
583 * The "tui reg" command now provides completion for all of the
584 available register groups, including target specific groups.
586 * The HISTSIZE environment variable is no longer read when determining
587 the size of GDB's command history. GDB now instead reads the dedicated
588 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
589 disables truncation of command history. Non-numeric values of GDBHISTSIZE
594 ** Memory ports can now be unbuffered.
598 ** gdb.Objfile objects have a new attribute "username",
599 which is the name of the objfile as specified by the user,
600 without, for example, resolving symlinks.
601 ** You can now write frame unwinders in Python.
602 ** gdb.Type objects have a new method "optimized_out",
603 returning optimized out gdb.Value instance of this type.
604 ** gdb.Value objects have new methods "reference_value" and
605 "const_value" which return a reference to the value and a
606 "const" version of the value respectively.
610 maint print symbol-cache
611 Print the contents of the symbol cache.
613 maint print symbol-cache-statistics
614 Print statistics of symbol cache usage.
616 maint flush-symbol-cache
617 Flush the contents of the symbol cache.
621 Start branch trace recording using Branch Trace Store (BTS) format.
624 Evaluate expression by using the compiler and print result.
628 Explicit commands for enabling and disabling tui mode.
631 set mpx bound on i386 and amd64
632 Support for bound table investigation on Intel MPX enabled applications.
636 Start branch trace recording using Intel Processor Trace format.
639 Print information about branch tracing internals.
641 maint btrace packet-history
642 Print the raw branch tracing data.
644 maint btrace clear-packet-history
645 Discard the stored raw branch tracing data.
648 Discard all branch tracing data. It will be fetched and processed
649 anew by the next "record" command.
654 Renamed from "set debug dwarf2-die".
656 Renamed from "show debug dwarf2-die".
659 Renamed from "set debug dwarf2-read".
660 show debug dwarf-read
661 Renamed from "show debug dwarf2-read".
663 maint set dwarf always-disassemble
664 Renamed from "maint set dwarf2 always-disassemble".
665 maint show dwarf always-disassemble
666 Renamed from "maint show dwarf2 always-disassemble".
668 maint set dwarf max-cache-age
669 Renamed from "maint set dwarf2 max-cache-age".
670 maint show dwarf max-cache-age
671 Renamed from "maint show dwarf2 max-cache-age".
674 show debug dwarf-line
675 Control display of debugging info regarding DWARF line processing.
679 Set the maximum number of candidates to be considered during
680 completion. The default value is 200. This limit allows GDB
681 to avoid generating large completion lists, the computation of
682 which can cause the debugger to become temporarily unresponsive.
684 set history remove-duplicates
685 show history remove-duplicates
686 Control the removal of duplicate history entries.
688 maint set symbol-cache-size
689 maint show symbol-cache-size
690 Control the size of the symbol cache.
692 set|show record btrace bts buffer-size
693 Set and show the size of the ring buffer used for branch tracing in
695 The obtained size may differ from the requested size. Use "info
696 record" to see the obtained buffer size.
698 set debug linux-namespaces
699 show debug linux-namespaces
700 Control display of debugging info regarding Linux namespaces.
702 set|show record btrace pt buffer-size
703 Set and show the size of the ring buffer used for branch tracing in
704 Intel Processor Trace format.
705 The obtained size may differ from the requested size. Use "info
706 record" to see the obtained buffer size.
708 maint set|show btrace pt skip-pad
709 Set and show whether PAD packets are skipped when computing the
712 * The command 'thread apply all' can now support new option '-ascending'
713 to call its specified command for all threads in ascending order.
715 * Python/Guile scripting
717 ** GDB now supports auto-loading of Python/Guile scripts contained in the
718 special section named `.debug_gdb_scripts'.
722 qXfer:btrace-conf:read
723 Return the branch trace configuration for the current thread.
725 Qbtrace-conf:bts:size
726 Set the requested ring buffer size for branch tracing in BTS format.
729 Enable Intel Procesor Trace-based branch tracing for the current
730 process. The remote stub reports support for this packet to GDB's
734 Set the requested ring buffer size for branch tracing in Intel Processor
738 Indicates a memory breakpoint instruction was executed, irrespective
739 of whether it was GDB that planted the breakpoint or the breakpoint
740 is hardcoded in the program. This is required for correct non-stop
744 Indicates the target stopped for a hardware breakpoint. This is
745 required for correct non-stop mode operation.
748 Return information about files on the remote system.
751 Return the full absolute name of the file that was executed to
752 create a process running on the remote system.
755 Select the filesystem on which vFile: operations with filename
756 arguments will operate. This is required for GDB to be able to
757 access files on remote targets where the remote stub does not
758 share a common filesystem with the inferior(s).
761 Indicates that a fork system call was executed.
764 Indicates that a vfork system call was executed.
766 vforkdone stop reason
767 Indicates that a vfork child of the specified process has executed
768 an exec or exit, allowing the vfork parent to resume execution.
770 fork-events and vfork-events features in qSupported
771 The qSupported packet allows GDB to request support for fork and
772 vfork events using new 'gdbfeatures' fork-events and vfork-events,
773 and the qSupported response can contain the corresponding
774 'stubfeatures'. Set and show commands can be used to display
775 whether these features are enabled.
777 * Extended-remote fork events
779 ** GDB now has support for fork events on extended-remote Linux
780 targets. For targets with Linux kernels 2.5.60 and later, this
781 enables follow-fork-mode and detach-on-fork for both fork and
782 vfork, as well as fork and vfork catchpoints.
784 * The info record command now shows the recording format and the
785 branch tracing configuration for the current thread when using
786 the btrace record target.
787 For the BTS format, it shows the ring buffer size.
789 * GDB now has support for DTrace USDT (Userland Static Defined
790 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
792 * GDB now supports access to vector registers on S/390 GNU/Linux
795 * Removed command line options
797 -xdb HP-UX XDB compatibility mode.
799 * Removed targets and native configurations
801 HP/PA running HP-UX hppa*-*-hpux*
802 Itanium running HP-UX ia64-*-hpux*
804 * New configure options
807 This configure option allows the user to build GDB with support for
808 Intel Processor Trace (default: auto). This requires libipt.
810 --with-libipt-prefix=PATH
811 Specify the path to the version of libipt that GDB should use.
812 $PATH/include should contain the intel-pt.h header and
813 $PATH/lib should contain the libipt.so library.
815 *** Changes in GDB 7.9.1
819 ** Xmethods can now specify a result type.
821 *** Changes in GDB 7.9
823 * GDB now supports hardware watchpoints on x86 GNU Hurd.
827 ** You can now access frame registers from Python scripts.
828 ** New attribute 'producer' for gdb.Symtab objects.
829 ** gdb.Objfile objects have a new attribute "progspace",
830 which is the gdb.Progspace object of the containing program space.
831 ** gdb.Objfile objects have a new attribute "owner".
832 ** gdb.Objfile objects have a new attribute "build_id",
833 which is the build ID generated when the file was built.
834 ** gdb.Objfile objects have a new method "add_separate_debug_file".
835 ** A new event "gdb.clear_objfiles" has been added, triggered when
836 selecting a new file to debug.
837 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
838 ** New function gdb.lookup_objfile.
840 New events which are triggered when GDB modifies the state of the
843 ** gdb.events.inferior_call_pre: Function call is about to be made.
844 ** gdb.events.inferior_call_post: Function call has just been made.
845 ** gdb.events.memory_changed: A memory location has been altered.
846 ** gdb.events.register_changed: A register has been altered.
848 * New Python-based convenience functions:
850 ** $_caller_is(name [, number_of_frames])
851 ** $_caller_matches(regexp [, number_of_frames])
852 ** $_any_caller_is(name [, number_of_frames])
853 ** $_any_caller_matches(regexp [, number_of_frames])
855 * GDB now supports the compilation and injection of source code into
856 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
857 to compile the source code to object code, and if successful, inject
858 and execute that code within the current context of the inferior.
859 Currently the C language is supported. The commands used to
860 interface with this new feature are:
862 compile code [-raw|-r] [--] [source code]
863 compile file [-raw|-r] filename
867 demangle [-l language] [--] name
868 Demangle "name" in the specified language, or the current language
869 if elided. This command is renamed from the "maint demangle" command.
870 The latter is kept as a no-op to avoid "maint demangle" being interpreted
871 as "maint demangler-warning".
873 queue-signal signal-name-or-number
874 Queue a signal to be delivered to the thread when it is resumed.
876 add-auto-load-scripts-directory directory
877 Add entries to the list of directories from which to load auto-loaded
880 maint print user-registers
881 List all currently available "user" registers.
883 compile code [-r|-raw] [--] [source code]
884 Compile, inject, and execute in the inferior the executable object
885 code produced by compiling the provided source code.
887 compile file [-r|-raw] filename
888 Compile and inject into the inferior the executable object code
889 produced by compiling the source code stored in the filename
892 * On resume, GDB now always passes the signal the program had stopped
893 for to the thread the signal was sent to, even if the user changed
894 threads before resuming. Previously GDB would often (but not
895 always) deliver the signal to the thread that happens to be current
898 * Conversely, the "signal" command now consistently delivers the
899 requested signal to the current thread. GDB now asks for
900 confirmation if the program had stopped for a signal and the user
901 switched threads meanwhile.
903 * "breakpoint always-inserted" modes "off" and "auto" merged.
905 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
906 won't remove breakpoints from the target until all threads stop,
907 even in non-stop mode. The "auto" mode has been removed, and "off"
908 is now the default mode.
912 set debug symbol-lookup
913 show debug symbol-lookup
914 Control display of debugging info regarding symbol lookup.
918 ** The -list-thread-groups command outputs an exit-code field for
919 inferiors that have exited.
923 MIPS SDE mips*-sde*-elf*
927 Support for these obsolete configurations has been removed.
929 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
930 SGI Irix-5.x mips-*-irix5*
931 SGI Irix-6.x mips-*-irix6*
932 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
933 VAX running Ultrix vax-*-ultrix*
935 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
936 and "assf"), have been removed. Use the "sharedlibrary" command, or
937 its alias "share", instead.
939 *** Changes in GDB 7.8
941 * New command line options
944 This is an alias for the --data-directory option.
946 * GDB supports printing and modifying of variable length automatic arrays
947 as specified in ISO C99.
949 * The ARM simulator now supports instruction level tracing
950 with or without disassembly.
954 GDB now has support for scripting using Guile. Whether this is
955 available is determined at configure time.
956 Guile version 2.0 or greater is required.
957 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
959 * New commands (for set/show, see "New options" below)
963 Invoke CODE by passing it to the Guile interpreter.
967 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
969 info auto-load guile-scripts [regexp]
970 Print the list of automatically loaded Guile scripts.
972 * The source command is now capable of sourcing Guile scripts.
973 This feature is dependent on the debugger being built with Guile support.
977 set print symbol-loading (off|brief|full)
978 show print symbol-loading
979 Control whether to print informational messages when loading symbol
980 information for a file. The default is "full", but when debugging
981 programs with large numbers of shared libraries the amount of output
984 set guile print-stack (none|message|full)
985 show guile print-stack
986 Show a stack trace when an error is encountered in a Guile script.
988 set auto-load guile-scripts (on|off)
989 show auto-load guile-scripts
990 Control auto-loading of Guile script files.
992 maint ada set ignore-descriptive-types (on|off)
993 maint ada show ignore-descriptive-types
994 Control whether the debugger should ignore descriptive types in Ada
995 programs. The default is not to ignore the descriptive types. See
996 the user manual for more details on descriptive types and the intended
997 usage of this option.
999 set auto-connect-native-target
1001 Control whether GDB is allowed to automatically connect to the
1002 native target for the run, attach, etc. commands when not connected
1003 to any target yet. See also "target native" below.
1005 set record btrace replay-memory-access (read-only|read-write)
1006 show record btrace replay-memory-access
1007 Control what memory accesses are allowed during replay.
1009 maint set target-async (on|off)
1010 maint show target-async
1011 This controls whether GDB targets operate in synchronous or
1012 asynchronous mode. Normally the default is asynchronous, if it is
1013 available; but this can be changed to more easily debug problems
1014 occurring only in synchronous mode.
1016 set mi-async (on|off)
1018 Control whether MI asynchronous mode is preferred. This supersedes
1019 "set target-async" of previous GDB versions.
1021 * "set target-async" is deprecated as a CLI option and is now an alias
1022 for "set mi-async" (only puts MI into async mode).
1024 * Background execution commands (e.g., "c&", "s&", etc.) are now
1025 possible ``out of the box'' if the target supports them. Previously
1026 the user would need to explicitly enable the possibility with the
1027 "set target-async on" command.
1029 * New features in the GDB remote stub, GDBserver
1031 ** New option --debug-format=option1[,option2,...] allows one to add
1032 additional text to each output. At present only timestamps
1033 are supported: --debug-format=timestamps.
1034 Timestamps can also be turned on with the
1035 "monitor set debug-format timestamps" command from GDB.
1037 * The 'record instruction-history' command now starts counting instructions
1038 at one. This also affects the instruction ranges reported by the
1039 'record function-call-history' command when given the /i modifier.
1041 * The command 'record function-call-history' supports a new modifier '/c' to
1042 indent the function names based on their call stack depth.
1043 The fields for the '/i' and '/l' modifier have been reordered.
1044 The source line range is now prefixed with 'at'.
1045 The instruction range is now prefixed with 'inst'.
1046 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1047 "record instruction-history" and "list" commands.
1049 * The ranges given as arguments to the 'record function-call-history' and
1050 'record instruction-history' commands are now inclusive.
1052 * The btrace record target now supports the 'record goto' command.
1053 For locations inside the execution trace, the back trace is computed
1054 based on the information stored in the execution trace.
1056 * The btrace record target supports limited reverse execution and replay.
1057 The target does not record data and therefore does not allow reading
1058 memory or registers.
1060 * The "catch syscall" command now works on s390*-linux* targets.
1062 * The "compare-sections" command is no longer specific to target
1063 remote. It now works with all targets.
1065 * All native targets are now consistently called "native".
1066 Consequently, the "target child", "target GNU", "target djgpp",
1067 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1068 commands have been replaced with "target native". The QNX/NTO port
1069 leaves the "procfs" target in place and adds a "native" target for
1070 consistency with other ports. The impact on users should be minimal
1071 as these commands previously either throwed an error, or were
1072 no-ops. The target's name is visible in the output of the following
1073 commands: "help target", "info target", "info files", "maint print
1076 * The "target native" command now connects to the native target. This
1077 can be used to launch native programs even when "set
1078 auto-connect-native-target" is set to off.
1080 * GDB now supports access to Intel MPX registers on GNU/Linux.
1082 * Support for Intel AVX-512 registers on GNU/Linux.
1083 Support displaying and modifying Intel AVX-512 registers
1084 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1086 * New remote packets
1088 qXfer:btrace:read's annex
1089 The qXfer:btrace:read packet supports a new annex 'delta' to read
1090 branch trace incrementally.
1094 ** Valid Python operations on gdb.Value objects representing
1095 structs/classes invoke the corresponding overloaded operators if
1097 ** New `Xmethods' feature in the Python API. Xmethods are
1098 additional methods or replacements for existing methods of a C++
1099 class. This feature is useful for those cases where a method
1100 defined in C++ source code could be inlined or optimized out by
1101 the compiler, making it unavailable to GDB.
1104 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1106 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1107 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1108 its alias "share", instead.
1110 * The commands "set remotebaud" and "show remotebaud" are no longer
1111 supported. Use "set serial baud" and "show serial baud" (respectively)
1116 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1117 target-async". The latter is left as a deprecated alias of the
1118 former for backward compatibility. If the target supports it,
1119 CLI background execution commands are now always possible by
1120 default, independently of whether the frontend stated a
1121 preference for asynchronous execution with "-gdb-set mi-async".
1122 Previously "-gdb-set target-async off" affected both MI execution
1123 commands and CLI execution commands.
1125 *** Changes in GDB 7.7
1127 * Improved support for process record-replay and reverse debugging on
1128 arm*-linux* targets. Support for thumb32 and syscall instruction
1129 recording has been added.
1131 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1133 * GDB now supports Fission DWP file format version 2.
1134 http://gcc.gnu.org/wiki/DebugFission
1136 * New convenience function "$_isvoid", to check whether an expression
1137 is void. A void expression is an expression where the type of the
1138 result is "void". For example, some convenience variables may be
1139 "void" when evaluated (e.g., "$_exitcode" before the execution of
1140 the program being debugged; or an undefined convenience variable).
1141 Another example, when calling a function whose return type is
1144 * The "maintenance print objfiles" command now takes an optional regexp.
1146 * The "catch syscall" command now works on arm*-linux* targets.
1148 * GDB now consistently shows "<not saved>" when printing values of
1149 registers the debug info indicates have not been saved in the frame
1150 and there's nowhere to retrieve them from
1151 (callee-saved/call-clobbered registers):
1156 (gdb) info registers rax
1159 Before, the former would print "<optimized out>", and the latter
1160 "*value not available*".
1162 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1167 ** Frame filters and frame decorators have been added.
1168 ** Temporary breakpoints are now supported.
1169 ** Line tables representation has been added.
1170 ** New attribute 'parent_type' for gdb.Field objects.
1171 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1172 ** New attribute 'name' for gdb.Type objects.
1176 Nios II ELF nios2*-*-elf
1177 Nios II GNU/Linux nios2*-*-linux
1178 Texas Instruments MSP430 msp430*-*-elf
1180 * Removed native configurations
1182 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1183 been removed. ELF variants of these configurations are kept supported.
1185 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1186 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1187 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1188 i[34567]86-*-openbsd3.[0-3]
1189 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1190 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1191 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1195 Like "catch throw", but catches a re-thrown exception.
1196 maint check-psymtabs
1197 Renamed from old "maint check-symtabs".
1199 Perform consistency checks on symtabs.
1200 maint expand-symtabs
1201 Expand symtabs matching an optional regexp.
1204 Display the details of GDB configure-time options.
1206 maint set|show per-command
1207 maint set|show per-command space
1208 maint set|show per-command time
1209 maint set|show per-command symtab
1210 Enable display of per-command gdb resource usage.
1212 remove-symbol-file FILENAME
1213 remove-symbol-file -a ADDRESS
1214 Remove a symbol file added via add-symbol-file. The file to remove
1215 can be identified by its filename or by an address that lies within
1216 the boundaries of this symbol file in memory.
1219 info exceptions REGEXP
1220 Display the list of Ada exceptions defined in the program being
1221 debugged. If provided, only the exceptions whose names match REGEXP
1226 set debug symfile off|on
1228 Control display of debugging info regarding reading symbol files and
1229 symbol tables within those files
1231 set print raw frame-arguments
1232 show print raw frame-arguments
1233 Set/show whether to print frame arguments in raw mode,
1234 disregarding any defined pretty-printers.
1236 set remote trace-status-packet
1237 show remote trace-status-packet
1238 Set/show the use of remote protocol qTStatus packet.
1242 Control display of debugging messages related to Nios II targets.
1246 Control whether target-assisted range stepping is enabled.
1248 set startup-with-shell
1249 show startup-with-shell
1250 Specifies whether Unix child processes are started via a shell or
1255 Use the target memory cache for accesses to the code segment. This
1256 improves performance of remote debugging (particularly disassembly).
1258 * You can now use a literal value 'unlimited' for options that
1259 interpret 0 or -1 as meaning "unlimited". E.g., "set
1260 trace-buffer-size unlimited" is now an alias for "set
1261 trace-buffer-size -1" and "set height unlimited" is now an alias for
1264 * The "set debug symtab-create" debugging option of GDB has been changed to
1265 accept a verbosity level. 0 means "off", 1 provides basic debugging
1266 output, and values of 2 or greater provides more verbose output.
1268 * New command-line options
1270 Display the details of GDB configure-time options.
1272 * The command 'tsave' can now support new option '-ctf' to save trace
1273 buffer in Common Trace Format.
1275 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1278 * GDB now implements the the C++ 'typeid' operator.
1280 * The new convenience variable $_exception holds the exception being
1281 thrown or caught at an exception-related catchpoint.
1283 * The exception-related catchpoints, like "catch throw", now accept a
1284 regular expression which can be used to filter exceptions by type.
1286 * The new convenience variable $_exitsignal is automatically set to
1287 the terminating signal number when the program being debugged dies
1288 due to an uncaught signal.
1292 ** All MI commands now accept an optional "--language" option.
1293 Support for this feature can be verified by using the "-list-features"
1294 command, which should contain "language-option".
1296 ** The new command -info-gdb-mi-command allows the user to determine
1297 whether a GDB/MI command is supported or not.
1299 ** The "^error" result record returned when trying to execute an undefined
1300 GDB/MI command now provides a variable named "code" whose content is the
1301 "undefined-command" error code. Support for this feature can be verified
1302 by using the "-list-features" command, which should contain
1303 "undefined-command-error-code".
1305 ** The -trace-save MI command can optionally save trace buffer in Common
1308 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1310 ** The command -data-list-register-values now accepts an optional
1311 "--skip-unavailable" option. When used, only the available registers
1314 ** The new command -trace-frame-collected dumps collected variables,
1315 computed expressions, tvars, memory and registers in a traceframe.
1317 ** The commands -stack-list-locals, -stack-list-arguments and
1318 -stack-list-variables now accept an option "--skip-unavailable".
1319 When used, only the available locals or arguments are displayed.
1321 ** The -exec-run command now accepts an optional "--start" option.
1322 When used, the command follows the same semantics as the "start"
1323 command, stopping the program's execution at the start of its
1324 main subprogram. Support for this feature can be verified using
1325 the "-list-features" command, which should contain
1326 "exec-run-start-option".
1328 ** The new commands -catch-assert and -catch-exceptions insert
1329 catchpoints stopping the program when Ada exceptions are raised.
1331 ** The new command -info-ada-exceptions provides the equivalent of
1332 the new "info exceptions" command.
1334 * New system-wide configuration scripts
1335 A GDB installation now provides scripts suitable for use as system-wide
1336 configuration scripts for the following systems:
1340 * GDB now supports target-assigned range stepping with remote targets.
1341 This improves the performance of stepping source lines by reducing
1342 the number of control packets from/to GDB. See "New remote packets"
1345 * GDB now understands the element 'tvar' in the XML traceframe info.
1346 It has the id of the collected trace state variables.
1348 * On S/390 targets that provide the transactional-execution feature,
1349 the program interruption transaction diagnostic block (TDB) is now
1350 represented as a number of additional "registers" in GDB.
1352 * New remote packets
1356 The vCont packet supports a new 'r' action, that tells the remote
1357 stub to step through an address range itself, without GDB
1358 involvemement at each single-step.
1360 qXfer:libraries-svr4:read's annex
1361 The previously unused annex of the qXfer:libraries-svr4:read packet
1362 is now used to support passing an argument list. The remote stub
1363 reports support for this argument list to GDB's qSupported query.
1364 The defined arguments are "start" and "prev", used to reduce work
1365 necessary for library list updating, resulting in significant
1368 * New features in the GDB remote stub, GDBserver
1370 ** GDBserver now supports target-assisted range stepping. Currently
1371 enabled on x86/x86_64 GNU/Linux targets.
1373 ** GDBserver now adds element 'tvar' in the XML in the reply to
1374 'qXfer:traceframe-info:read'. It has the id of the collected
1375 trace state variables.
1377 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1380 * New 'z' formatter for printing and examining memory, this displays the
1381 value as hexadecimal zero padded on the left to the size of the type.
1383 * GDB can now use Windows x64 unwinding data.
1385 * The "set remotebaud" command has been replaced by "set serial baud".
1386 Similarly, "show remotebaud" has been replaced by "show serial baud".
1387 The "set remotebaud" and "show remotebaud" commands are still available
1388 to provide backward compatibility with older versions of GDB.
1390 *** Changes in GDB 7.6
1392 * Target record has been renamed to record-full.
1393 Record/replay is now enabled with the "record full" command.
1394 This also affects settings that are associated with full record/replay
1395 that have been moved from "set/show record" to "set/show record full":
1397 set|show record full insn-number-max
1398 set|show record full stop-at-limit
1399 set|show record full memory-query
1401 * A new record target "record-btrace" has been added. The new target
1402 uses hardware support to record the control-flow of a process. It
1403 does not support replaying the execution, but it implements the
1404 below new commands for investigating the recorded execution log.
1405 This new recording method can be enabled using:
1409 The "record-btrace" target is only available on Intel Atom processors
1410 and requires a Linux kernel 2.6.32 or later.
1412 * Two new commands have been added for record/replay to give information
1413 about the recorded execution without having to replay the execution.
1414 The commands are only supported by "record btrace".
1416 record instruction-history prints the execution history at
1417 instruction granularity
1419 record function-call-history prints the execution history at
1420 function granularity
1422 * New native configurations
1424 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1425 FreeBSD/powerpc powerpc*-*-freebsd
1426 x86_64/Cygwin x86_64-*-cygwin*
1427 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1431 ARM AArch64 aarch64*-*-elf
1432 ARM AArch64 GNU/Linux aarch64*-*-linux
1433 Lynx 178 PowerPC powerpc-*-lynx*178
1434 x86_64/Cygwin x86_64-*-cygwin*
1435 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1437 * If the configured location of system.gdbinit file (as given by the
1438 --with-system-gdbinit option at configure time) is in the
1439 data-directory (as specified by --with-gdb-datadir at configure
1440 time) or in one of its subdirectories, then GDB will look for the
1441 system-wide init file in the directory specified by the
1442 --data-directory command-line option.
1444 * New command line options:
1446 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1447 other initialization files, unlike -nx which disables all of them.
1449 * Removed command line options
1451 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1454 * The 'ptype' and 'whatis' commands now accept an argument to control
1457 * 'info proc' now works on some core files.
1461 ** Vectors can be created with gdb.Type.vector.
1463 ** Python's atexit.register now works in GDB.
1465 ** Types can be pretty-printed via a Python API.
1467 ** Python 3 is now supported (in addition to Python 2.4 or later)
1469 ** New class gdb.Architecture exposes GDB's internal representation
1470 of architecture in the Python API.
1472 ** New method Frame.architecture returns the gdb.Architecture object
1473 corresponding to the frame's architecture.
1475 * New Python-based convenience functions:
1477 ** $_memeq(buf1, buf2, length)
1478 ** $_streq(str1, str2)
1480 ** $_regex(str, regex)
1482 * The 'cd' command now defaults to using '~' (the home directory) if not
1485 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1486 default for GCC since November 2000.
1488 * The command 'forward-search' can now be abbreviated as 'fo'.
1490 * The command 'info tracepoints' can now display 'installed on target'
1491 or 'not installed on target' for each non-pending location of tracepoint.
1493 * New configure options
1495 --enable-libmcheck/--disable-libmcheck
1496 By default, development versions are built with -lmcheck on hosts
1497 that support it, in order to help track memory corruption issues.
1498 Release versions, on the other hand, are built without -lmcheck
1499 by default. The --enable-libmcheck/--disable-libmcheck configure
1500 options allow the user to override that default.
1501 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1502 This configure option allows the user to build GDB with
1503 libbabeltrace using which GDB can read Common Trace Format data.
1505 * New commands (for set/show, see "New options" below)
1508 Catch signals. This is similar to "handle", but allows commands and
1509 conditions to be attached.
1512 List the BFDs known to GDB.
1514 python-interactive [command]
1516 Start a Python interactive prompt, or evaluate the optional command
1517 and print the result of expressions.
1520 "py" is a new alias for "python".
1522 enable type-printer [name]...
1523 disable type-printer [name]...
1524 Enable or disable type printers.
1528 ** For the Renesas Super-H architecture, the "regs" command has been removed
1529 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1534 set print type methods (on|off)
1535 show print type methods
1536 Control whether method declarations are displayed by "ptype".
1537 The default is to show them.
1539 set print type typedefs (on|off)
1540 show print type typedefs
1541 Control whether typedef definitions are displayed by "ptype".
1542 The default is to show them.
1544 set filename-display basename|relative|absolute
1545 show filename-display
1546 Control the way in which filenames is displayed.
1547 The default is "relative", which preserves previous behavior.
1549 set trace-buffer-size
1550 show trace-buffer-size
1551 Request target to change the size of trace buffer.
1553 set remote trace-buffer-size-packet auto|on|off
1554 show remote trace-buffer-size-packet
1555 Control the use of the remote protocol `QTBuffer:size' packet.
1559 Control display of debugging messages related to ARM AArch64.
1562 set debug coff-pe-read
1563 show debug coff-pe-read
1564 Control display of debugging messages related to reading of COFF/PE
1569 Control display of debugging messages related to Mach-O symbols
1572 set debug notification
1573 show debug notification
1574 Control display of debugging info for async remote notification.
1578 ** Command parameter changes are now notified using new async record
1579 "=cmd-param-changed".
1580 ** Trace frame changes caused by command "tfind" are now notified using
1581 new async record "=traceframe-changed".
1582 ** The creation, deletion and modification of trace state variables
1583 are now notified using new async records "=tsv-created",
1584 "=tsv-deleted" and "=tsv-modified".
1585 ** The start and stop of process record are now notified using new
1586 async record "=record-started" and "=record-stopped".
1587 ** Memory changes are now notified using new async record
1589 ** The data-disassemble command response will include a "fullname" field
1590 containing the absolute file name when source has been requested.
1591 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1592 command, to allow pattern filling of memory areas.
1593 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1594 library load/unload events.
1595 ** The response to breakpoint commands and breakpoint async records
1596 includes an "installed" field containing a boolean state about each
1597 non-pending tracepoint location is whether installed on target or not.
1598 ** Output of the "-trace-status" command includes a "trace-file" field
1599 containing the name of the trace file being examined. This field is
1600 optional, and only present when examining a trace file.
1601 ** The "fullname" field is now always present along with the "file" field,
1602 even if the file cannot be found by GDB.
1604 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1605 You must have the LZMA library available when configuring GDB for this
1606 feature to be enabled. For more information, see:
1607 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1609 * New remote packets
1612 Set the size of trace buffer. The remote stub reports support for this
1613 packet to gdb's qSupported query.
1616 Enable Branch Trace Store (BTS)-based branch tracing for the current
1617 thread. The remote stub reports support for this packet to gdb's
1621 Disable branch tracing for the current thread. The remote stub reports
1622 support for this packet to gdb's qSupported query.
1625 Read the traced branches for the current thread. The remote stub
1626 reports support for this packet to gdb's qSupported query.
1628 *** Changes in GDB 7.5
1630 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1631 for more x32 ABI info.
1633 * GDB now supports access to MIPS DSP registers on Linux targets.
1635 * GDB now supports debugging microMIPS binaries.
1637 * The "info os" command on GNU/Linux can now display information on
1638 several new classes of objects managed by the operating system:
1639 "info os procgroups" lists process groups
1640 "info os files" lists file descriptors
1641 "info os sockets" lists internet-domain sockets
1642 "info os shm" lists shared-memory regions
1643 "info os semaphores" lists semaphores
1644 "info os msg" lists message queues
1645 "info os modules" lists loaded kernel modules
1647 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1648 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1649 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1650 options and inspect the probe arguments using the new $_probe_arg family
1651 of convenience variables. You can obtain more information about SystemTap
1652 in <http://sourceware.org/systemtap/>.
1654 * GDB now supports reversible debugging on ARM, it allows you to
1655 debug basic ARM and THUMB instructions, and provides
1656 record/replay support.
1658 * The option "symbol-reloading" has been deleted as it is no longer used.
1662 ** GDB commands implemented in Python can now be put in command class
1665 ** The "maint set python print-stack on|off" is now deleted.
1667 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1668 apply "flag enum"-style pretty-printing to any enum.
1670 ** gdb.lookup_symbol can now work when there is no current frame.
1672 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1673 the source at which the symbol was defined.
1675 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1676 method 'value'. The former indicates whether the symbol needs a
1677 frame in order to compute its value, and the latter computes the
1680 ** A new method 'referenced_value' on gdb.Value objects which can
1681 dereference pointer as well as C++ reference values.
1683 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1684 which return the global and static blocks (as gdb.Block objects),
1685 of the underlying symbol table, respectively.
1687 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1688 object associated with a PC value.
1690 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1691 of the address range occupied by code for the current source line.
1693 * Go language support.
1694 GDB now supports debugging programs written in the Go programming
1697 * GDBserver now supports stdio connections.
1698 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1700 * The binary "gdbtui" can no longer be built or installed.
1701 Use "gdb -tui" instead.
1703 * GDB will now print "flag" enums specially. A flag enum is one where
1704 all the enumerator values have no bits in common when pairwise
1705 "and"ed. When printing a value whose type is a flag enum, GDB will
1706 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1707 (gdb) print (enum E) 3
1710 * The filename part of a linespec will now match trailing components
1711 of a source file name. For example, "break gcc/expr.c:1000" will
1712 now set a breakpoint in build/gcc/expr.c, but not
1713 build/libcpp/expr.c.
1715 * The "info proc" and "generate-core-file" commands will now also
1716 work on remote targets connected to GDBserver on Linux.
1718 * The command "info catch" has been removed. It has been disabled
1719 since December 2007.
1721 * The "catch exception" and "catch assert" commands now accept
1722 a condition at the end of the command, much like the "break"
1723 command does. For instance:
1725 (gdb) catch exception Constraint_Error if Barrier = True
1727 Previously, it was possible to add a condition to such catchpoints,
1728 but it had to be done as a second step, after the catchpoint had been
1729 created, using the "condition" command.
1731 * The "info static-tracepoint-marker" command will now also work on
1732 native Linux targets with in-process agent.
1734 * GDB can now set breakpoints on inlined functions.
1736 * The .gdb_index section has been updated to include symbols for
1737 inlined functions. GDB will ignore older .gdb_index sections by
1738 default, which could cause symbol files to be loaded more slowly
1739 until their .gdb_index sections can be recreated. The new command
1740 "set use-deprecated-index-sections on" will cause GDB to use any older
1741 .gdb_index sections it finds. This will restore performance, but the
1742 ability to set breakpoints on inlined functions will be lost in symbol
1743 files with older .gdb_index sections.
1745 The .gdb_index section has also been updated to record more information
1746 about each symbol. This speeds up the "info variables", "info functions"
1747 and "info types" commands when used with programs having the .gdb_index
1748 section, as well as speeding up debugging with shared libraries using
1749 the .gdb_index section.
1751 * Ada support for GDB/MI Variable Objects has been added.
1753 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1758 ** New command -info-os is the MI equivalent of "info os".
1760 ** Output logs ("set logging" and related) now include MI output.
1764 ** "set use-deprecated-index-sections on|off"
1765 "show use-deprecated-index-sections on|off"
1766 Controls the use of deprecated .gdb_index sections.
1768 ** "catch load" and "catch unload" can be used to stop when a shared
1769 library is loaded or unloaded, respectively.
1771 ** "enable count" can be used to auto-disable a breakpoint after
1774 ** "info vtbl" can be used to show the virtual method tables for
1775 C++ and Java objects.
1777 ** "explore" and its sub commands "explore value" and "explore type"
1778 can be used to recursively explore values and types of
1779 expressions. These commands are available only if GDB is
1780 configured with '--with-python'.
1782 ** "info auto-load" shows status of all kinds of auto-loaded files,
1783 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1784 sequences of commands files, "info auto-load python-scripts"
1785 shows status of auto-loading Python script files,
1786 "info auto-load local-gdbinit" shows status of loading init file
1787 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1788 status of inferior specific thread debugging shared library loading.
1790 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1791 and "show auto-load-scripts" commands have been deprecated, use their
1792 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1793 and "show auto-load python-scripts" counterparts instead.
1795 ** "dprintf location,format,args..." creates a dynamic printf, which
1796 is basically a breakpoint that does a printf and immediately
1797 resumes your program's execution, so it is like a printf that you
1798 can insert dynamically at runtime instead of at compiletime.
1800 ** "set print symbol"
1802 Controls whether GDB attempts to display the symbol, if any,
1803 corresponding to addresses it prints. This defaults to "on", but
1804 you can set it to "off" to restore GDB's previous behavior.
1806 * Deprecated commands
1808 ** For the Renesas Super-H architecture, the "regs" command has been
1809 deprecated, and "info all-registers" should be used instead.
1813 Renesas RL78 rl78-*-elf
1814 HP OpenVMS ia64 ia64-hp-openvms*
1816 * GDBserver supports evaluation of breakpoint conditions. When
1817 support is advertised by GDBserver, GDB may be told to send the
1818 breakpoint conditions in bytecode form to GDBserver. GDBserver
1819 will only report the breakpoint trigger to GDB when its condition
1824 set mips compression
1825 show mips compression
1826 Select the compressed ISA encoding used in functions that have no symbol
1827 information available. The encoding can be set to either of:
1830 and is updated automatically from ELF file flags if available.
1832 set breakpoint condition-evaluation
1833 show breakpoint condition-evaluation
1834 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1835 GDBserver ("target"). Default option "auto" chooses the most efficient
1837 This option can improve debugger efficiency depending on the speed of the
1841 Disable auto-loading globally.
1844 Show auto-loading setting of all kinds of auto-loaded files.
1846 set auto-load gdb-scripts on|off
1847 show auto-load gdb-scripts
1848 Control auto-loading of GDB canned sequences of commands files.
1850 set auto-load python-scripts on|off
1851 show auto-load python-scripts
1852 Control auto-loading of Python script files.
1854 set auto-load local-gdbinit on|off
1855 show auto-load local-gdbinit
1856 Control loading of init file (.gdbinit) from current directory.
1858 set auto-load libthread-db on|off
1859 show auto-load libthread-db
1860 Control auto-loading of inferior specific thread debugging shared library.
1862 set auto-load scripts-directory <dir1>[:<dir2>...]
1863 show auto-load scripts-directory
1864 Set a list of directories from which to load auto-loaded scripts.
1865 Automatically loaded Python scripts and GDB scripts are located in one
1866 of the directories listed by this option.
1867 The delimiter (':' above) may differ according to the host platform.
1869 set auto-load safe-path <dir1>[:<dir2>...]
1870 show auto-load safe-path
1871 Set a list of directories from which it is safe to auto-load files.
1872 The delimiter (':' above) may differ according to the host platform.
1874 set debug auto-load on|off
1875 show debug auto-load
1876 Control display of debugging info for auto-loading the files above.
1878 set dprintf-style gdb|call|agent
1880 Control the way in which a dynamic printf is performed; "gdb"
1881 requests a GDB printf command, while "call" causes dprintf to call a
1882 function in the inferior. "agent" requests that the target agent
1883 (such as GDBserver) do the printing.
1885 set dprintf-function <expr>
1886 show dprintf-function
1887 set dprintf-channel <expr>
1888 show dprintf-channel
1889 Set the function and optional first argument to the call when using
1890 the "call" style of dynamic printf.
1892 set disconnected-dprintf on|off
1893 show disconnected-dprintf
1894 Control whether agent-style dynamic printfs continue to be in effect
1895 after GDB disconnects.
1897 * New configure options
1899 --with-auto-load-dir
1900 Configure default value for the 'set auto-load scripts-directory'
1901 setting above. It defaults to '$debugdir:$datadir/auto-load',
1902 $debugdir representing global debugging info directories (available
1903 via 'show debug-file-directory') and $datadir representing GDB's data
1904 directory (available via 'show data-directory').
1906 --with-auto-load-safe-path
1907 Configure default value for the 'set auto-load safe-path' setting
1908 above. It defaults to the --with-auto-load-dir setting.
1910 --without-auto-load-safe-path
1911 Set 'set auto-load safe-path' to '/', effectively disabling this
1914 * New remote packets
1916 z0/z1 conditional breakpoints extension
1918 The z0/z1 breakpoint insertion packets have been extended to carry
1919 a list of conditional expressions over to the remote stub depending on the
1920 condition evaluation mode. The use of this extension can be controlled
1921 via the "set remote conditional-breakpoints-packet" command.
1925 Specify the signals which the remote stub may pass to the debugged
1926 program without GDB involvement.
1928 * New command line options
1930 --init-command=FILE, -ix Like --command, -x but execute it
1931 before loading inferior.
1932 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1933 execute it before loading inferior.
1935 *** Changes in GDB 7.4
1937 * GDB now handles ambiguous linespecs more consistently; the existing
1938 FILE:LINE support has been expanded to other types of linespecs. A
1939 breakpoint will now be set on all matching locations in all
1940 inferiors, and locations will be added or removed according to
1943 * GDB now allows you to skip uninteresting functions and files when
1944 stepping with the "skip function" and "skip file" commands.
1946 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1947 and "show remote hardware-watchpoint-length-limit". These allows to
1948 set or show the maximum length limit (in bytes) of a remote
1949 target hardware watchpoint.
1951 This allows e.g. to use "unlimited" hardware watchpoints with the
1952 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1953 watchpoints are slower than real hardware watchpoints but are
1954 significantly faster than gdb software watchpoints.
1958 ** The register_pretty_printer function in module gdb.printing now takes
1959 an optional `replace' argument. If True, the new printer replaces any
1962 ** The "maint set python print-stack on|off" command has been
1963 deprecated and will be deleted in GDB 7.5.
1964 A new command: "set python print-stack none|full|message" has
1965 replaced it. Additionally, the default for "print-stack" is
1966 now "message", which just prints the error message without
1969 ** A prompt substitution hook (prompt_hook) is now available to the
1972 ** A new Python module, gdb.prompt has been added to the GDB Python
1973 modules library. This module provides functionality for
1974 escape sequences in prompts (used by set/show
1975 extended-prompt). These escape sequences are replaced by their
1976 corresponding value.
1978 ** Python commands and convenience-functions located in
1979 'data-directory'/python/gdb/command and
1980 'data-directory'/python/gdb/function are now automatically loaded
1983 ** Blocks now provide four new attributes. global_block and
1984 static_block will return the global and static blocks
1985 respectively. is_static and is_global are boolean attributes
1986 that indicate if the block is one of those two types.
1988 ** Symbols now provide the "type" attribute, the type of the symbol.
1990 ** The "gdb.breakpoint" function has been deprecated in favor of
1993 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1994 of a function. This class is based on the "finish" command
1995 available in the CLI.
1997 ** Type objects for struct and union types now allow access to
1998 the fields using standard Python dictionary (mapping) methods.
1999 For example, "some_type['myfield']" now works, as does
2000 "some_type.items()".
2002 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2005 ** A new function, "deep_items" has been added to the gdb.types
2006 module in the GDB Python modules library. This function returns
2007 an iterator over the fields of a struct or union type. Unlike
2008 the standard Python "iteritems" method, it will recursively traverse
2009 any anonymous fields.
2013 ** "*stopped" events can report several new "reason"s, such as
2016 ** Breakpoint changes are now notified using new async records, like
2017 "=breakpoint-modified".
2019 ** New command -ada-task-info.
2021 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2022 $sdir specifies the default system locations of shared libraries.
2023 $pdir specifies the directory where the libpthread used by the application
2026 GDB no longer looks in $sdir and $pdir after it has searched the directories
2027 mentioned in libthread-db-search-path. If you want to search those
2028 directories, they must be specified in libthread-db-search-path.
2029 The default value of libthread-db-search-path on GNU/Linux and Solaris
2030 systems is now "$sdir:$pdir".
2032 $pdir is not supported by gdbserver, it is currently ignored.
2033 $sdir is supported by gdbserver.
2035 * New configure option --with-iconv-bin.
2036 When using the internationalization support like the one in the GNU C
2037 library, GDB will invoke the "iconv" program to get a list of supported
2038 character sets. If this program lives in a non-standard location, one can
2039 use this option to specify where to find it.
2041 * When natively debugging programs on PowerPC BookE processors running
2042 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2043 watchpoints, which specify a mask in addition to an address to watch.
2044 The mask specifies that some bits of an address (the bits which are
2045 reset in the mask) should be ignored when matching the address accessed
2046 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2047 section in the user manual for more details.
2049 * The new option --once causes GDBserver to stop listening for connections once
2050 the first connection is made. The listening port used by GDBserver will
2051 become available after that.
2053 * New commands "info macros" and "alias" have been added.
2055 * New function parameters suffix @entry specifies value of function parameter
2056 at the time the function got called. Entry values are available only since
2062 "!" is now an alias of the "shell" command.
2063 Note that no space is needed between "!" and SHELL COMMAND.
2067 watch EXPRESSION mask MASK_VALUE
2068 The watch command now supports the mask argument which allows creation
2069 of masked watchpoints, if the current architecture supports this feature.
2071 info auto-load-scripts [REGEXP]
2072 This command was formerly named "maintenance print section-scripts".
2073 It is now generally useful and is no longer a maintenance-only command.
2075 info macro [-all] [--] MACRO
2076 The info macro command has new options `-all' and `--'. The first for
2077 printing all definitions of a macro. The second for explicitly specifying
2078 the end of arguments and the beginning of the macro name in case the macro
2079 name starts with a hyphen.
2081 collect[/s] EXPRESSIONS
2082 The tracepoint collect command now takes an optional modifier "/s"
2083 that directs it to dereference pointer-to-character types and
2084 collect the bytes of memory up to a zero byte. The behavior is
2085 similar to what you see when you use the regular print command on a
2086 string. An optional integer following the "/s" sets a bound on the
2087 number of bytes that will be collected.
2090 The trace start command now interprets any supplied arguments as a
2091 note to be recorded with the trace run, with an effect similar to
2092 setting the variable trace-notes.
2095 The trace stop command now interprets any arguments as a note to be
2096 mentioned along with the tstatus report that the trace was stopped
2097 with a command. The effect is similar to setting the variable
2100 * Tracepoints can now be enabled and disabled at any time after a trace
2101 experiment has been started using the standard "enable" and "disable"
2102 commands. It is now possible to start a trace experiment with no enabled
2103 tracepoints; GDB will display a warning, but will allow the experiment to
2104 begin, assuming that tracepoints will be enabled as needed while the trace
2107 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2108 locations with 4-byte instructions, when they were previously
2109 limited to locations with instructions of 5 bytes or longer.
2113 set debug dwarf2-read
2114 show debug dwarf2-read
2115 Turns on or off display of debugging messages related to reading
2116 DWARF debug info. The default is off.
2118 set debug symtab-create
2119 show debug symtab-create
2120 Turns on or off display of debugging messages related to symbol table
2121 creation. The default is off.
2124 show extended-prompt
2125 Set the GDB prompt, and allow escape sequences to be inserted to
2126 display miscellaneous information (see 'help set extended-prompt'
2127 for the list of sequences). This prompt (and any information
2128 accessed through the escape sequences) is updated every time the
2129 prompt is displayed.
2131 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2132 show print entry-values
2133 Set printing of frame argument values at function entry. In some cases
2134 GDB can determine the value of function argument which was passed by the
2135 function caller, even if the value was modified inside the called function.
2137 set debug entry-values
2138 show debug entry-values
2139 Control display of debugging info for determining frame argument values at
2140 function entry and virtual tail call frames.
2142 set basenames-may-differ
2143 show basenames-may-differ
2144 Set whether a source file may have multiple base names.
2145 (A "base name" is the name of a file with the directory part removed.
2146 Example: The base name of "/home/user/hello.c" is "hello.c".)
2147 If set, GDB will canonicalize file names (e.g., expand symlinks)
2148 before comparing them. Canonicalization is an expensive operation,
2149 but it allows the same file be known by more than one base name.
2150 If not set (the default), all source files are assumed to have just
2151 one base name, and gdb will do file name comparisons more efficiently.
2157 Set a user name and notes for the current and any future trace runs.
2158 This is useful for long-running and/or disconnected traces, to
2159 inform others (or yourself) as to who is running the trace, supply
2160 contact information, or otherwise explain what is going on.
2162 set trace-stop-notes
2163 show trace-stop-notes
2164 Set a note attached to the trace run, that is displayed when the
2165 trace has been stopped by a tstop command. This is useful for
2166 instance as an explanation, if you are stopping a trace run that was
2167 started by someone else.
2169 * New remote packets
2173 Dynamically enable a tracepoint in a started trace experiment.
2177 Dynamically disable a tracepoint in a started trace experiment.
2181 Set the user and notes of the trace run.
2185 Query the current status of a tracepoint.
2189 Query the minimum length of instruction at which a fast tracepoint may
2192 * Dcache size (number of lines) and line-size are now runtime-configurable
2193 via "set dcache line" and "set dcache line-size" commands.
2197 Texas Instruments TMS320C6x tic6x-*-*
2201 Renesas RL78 rl78-*-elf
2203 *** Changes in GDB 7.3.1
2205 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2207 *** Changes in GDB 7.3
2209 * GDB has a new command: "thread find [REGEXP]".
2210 It finds the thread id whose name, target id, or thread extra info
2211 matches the given regular expression.
2213 * The "catch syscall" command now works on mips*-linux* targets.
2215 * The -data-disassemble MI command now supports modes 2 and 3 for
2216 dumping the instruction opcodes.
2218 * New command line options
2220 -data-directory DIR Specify DIR as the "data-directory".
2221 This is mostly for testing purposes.
2223 * The "maint set python auto-load on|off" command has been renamed to
2224 "set auto-load-scripts on|off".
2226 * GDB has a new command: "set directories".
2227 It is like the "dir" command except that it replaces the
2228 source path list instead of augmenting it.
2230 * GDB now understands thread names.
2232 On GNU/Linux, "info threads" will display the thread name as set by
2233 prctl or pthread_setname_np.
2235 There is also a new command, "thread name", which can be used to
2236 assign a name internally for GDB to display.
2239 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2240 has been integrated into GDB.
2244 ** The function gdb.Write now accepts an optional keyword 'stream'.
2245 This keyword, when provided, will direct the output to either
2246 stdout, stderr, or GDB's logging output.
2248 ** Parameters can now be be sub-classed in Python, and in particular
2249 you may implement the get_set_doc and get_show_doc functions.
2250 This improves how Parameter set/show documentation is processed
2251 and allows for more dynamic content.
2253 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2254 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2255 have an is_valid method.
2257 ** Breakpoints can now be sub-classed in Python, and in particular
2258 you may implement a 'stop' function that is executed each time
2259 the inferior reaches that breakpoint.
2261 ** New function gdb.lookup_global_symbol looks up a global symbol.
2263 ** GDB values in Python are now callable if the value represents a
2264 function. For example, if 'some_value' represents a function that
2265 takes two integer parameters and returns a value, you can call
2266 that function like so:
2268 result = some_value (10,20)
2270 ** Module gdb.types has been added.
2271 It contains a collection of utilities for working with gdb.Types objects:
2272 get_basic_type, has_field, make_enum_dict.
2274 ** Module gdb.printing has been added.
2275 It contains utilities for writing and registering pretty-printers.
2276 New classes: PrettyPrinter, SubPrettyPrinter,
2277 RegexpCollectionPrettyPrinter.
2278 New function: register_pretty_printer.
2280 ** New commands "info pretty-printers", "enable pretty-printer" and
2281 "disable pretty-printer" have been added.
2283 ** gdb.parameter("directories") is now available.
2285 ** New function gdb.newest_frame returns the newest frame in the
2288 ** The gdb.InferiorThread class has a new "name" attribute. This
2289 holds the thread's name.
2291 ** Python Support for Inferior events.
2292 Python scripts can add observers to be notified of events
2293 occurring in the process being debugged.
2294 The following events are currently supported:
2295 - gdb.events.cont Continue event.
2296 - gdb.events.exited Inferior exited event.
2297 - gdb.events.stop Signal received, and Breakpoint hit events.
2301 ** GDB now puts template parameters in scope when debugging in an
2302 instantiation. For example, if you have:
2304 template<int X> int func (void) { return X; }
2306 then if you step into func<5>, "print X" will show "5". This
2307 feature requires proper debuginfo support from the compiler; it
2308 was added to GCC 4.5.
2310 ** The motion commands "next", "finish", "until", and "advance" now
2311 work better when exceptions are thrown. In particular, GDB will
2312 no longer lose control of the inferior; instead, the GDB will
2313 stop the inferior at the point at which the exception is caught.
2314 This functionality requires a change in the exception handling
2315 code that was introduced in GCC 4.5.
2317 * GDB now follows GCC's rules on accessing volatile objects when
2318 reading or writing target state during expression evaluation.
2319 One notable difference to prior behavior is that "print x = 0"
2320 no longer generates a read of x; the value of the assignment is
2321 now always taken directly from the value being assigned.
2323 * GDB now has some support for using labels in the program's source in
2324 linespecs. For instance, you can use "advance label" to continue
2325 execution to a label.
2327 * GDB now has support for reading and writing a new .gdb_index
2328 section. This section holds a fast index of DWARF debugging
2329 information and can be used to greatly speed up GDB startup and
2330 operation. See the documentation for `save gdb-index' for details.
2332 * The "watch" command now accepts an optional "-location" argument.
2333 When used, this causes GDB to watch the memory referred to by the
2334 expression. Such a watchpoint is never deleted due to it going out
2337 * GDB now supports thread debugging of core dumps on GNU/Linux.
2339 GDB now activates thread debugging using the libthread_db library
2340 when debugging GNU/Linux core dumps, similarly to when debugging
2341 live processes. As a result, when debugging a core dump file, GDB
2342 is now able to display pthread_t ids of threads. For example, "info
2343 threads" shows the same output as when debugging the process when it
2344 was live. In earlier releases, you'd see something like this:
2347 * 1 LWP 6780 main () at main.c:10
2349 While now you see this:
2352 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2354 It is also now possible to inspect TLS variables when debugging core
2357 When debugging a core dump generated on a machine other than the one
2358 used to run GDB, you may need to point GDB at the correct
2359 libthread_db library with the "set libthread-db-search-path"
2360 command. See the user manual for more details on this command.
2362 * When natively debugging programs on PowerPC BookE processors running
2363 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2364 which stop execution of the inferior whenever it executes an instruction
2365 at any address within the specified range. See the "PowerPC Embedded"
2366 section in the user manual for more details.
2368 * New features in the GDB remote stub, GDBserver
2370 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2371 and i686 LynxOS (version 5.x).
2373 ** GDBserver is now supported on Blackfin Linux.
2375 * New native configurations
2377 ia64 HP-UX ia64-*-hpux*
2381 Analog Devices, Inc. Blackfin Processor bfin-*
2383 * Ada task switching is now supported on sparc-elf targets when
2384 debugging a program using the Ravenscar Profile. For more information,
2385 see the "Tasking Support when using the Ravenscar Profile" section
2386 in the GDB user manual.
2388 * Guile support was removed.
2390 * New features in the GNU simulator
2392 ** The --map-info flag lists all known core mappings.
2394 ** CFI flashes may be simulated via the "cfi" device.
2396 *** Changes in GDB 7.2
2398 * Shared library support for remote targets by default
2400 When GDB is configured for a generic, non-OS specific target, like
2401 for example, --target=arm-eabi or one of the many *-*-elf targets,
2402 GDB now queries remote stubs for loaded shared libraries using the
2403 `qXfer:libraries:read' packet. Previously, shared library support
2404 was always disabled for such configurations.
2408 ** Argument Dependent Lookup (ADL)
2410 In C++ ADL lookup directs function search to the namespaces of its
2411 arguments even if the namespace has not been imported.
2421 Here the compiler will search for `foo' in the namespace of 'b'
2422 and find A::foo. GDB now supports this. This construct is commonly
2423 used in the Standard Template Library for operators.
2425 ** Improved User Defined Operator Support
2427 In addition to member operators, GDB now supports lookup of operators
2428 defined in a namespace and imported with a `using' directive, operators
2429 defined in the global scope, operators imported implicitly from an
2430 anonymous namespace, and the ADL operators mentioned in the previous
2432 GDB now also supports proper overload resolution for all the previously
2433 mentioned flavors of operators.
2435 ** static const class members
2437 Printing of static const class members that are initialized in the
2438 class definition has been fixed.
2440 * Windows Thread Information Block access.
2442 On Windows targets, GDB now supports displaying the Windows Thread
2443 Information Block (TIB) structure. This structure is visible either
2444 by using the new command `info w32 thread-information-block' or, by
2445 dereferencing the new convenience variable named `$_tlb', a
2446 thread-specific pointer to the TIB. This feature is also supported
2447 when remote debugging using GDBserver.
2449 * Static tracepoints
2451 Static tracepoints are calls in the user program into a tracing
2452 library. One such library is a port of the LTTng kernel tracer to
2453 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2454 When debugging with GDBserver, GDB now supports combining the GDB
2455 tracepoint machinery with such libraries. For example: the user can
2456 use GDB to probe a static tracepoint marker (a call from the user
2457 program into the tracing library) with the new "strace" command (see
2458 "New commands" below). This creates a "static tracepoint" in the
2459 breakpoint list, that can be manipulated with the same feature set
2460 as fast and regular tracepoints. E.g., collect registers, local and
2461 global variables, collect trace state variables, and define
2462 tracepoint conditions. In addition, the user can collect extra
2463 static tracepoint marker specific data, by collecting the new
2464 $_sdata internal variable. When analyzing the trace buffer, you can
2465 inspect $_sdata like any other variable available to GDB. For more
2466 information, see the "Tracepoints" chapter in GDB user manual. New
2467 remote packets have been defined to support static tracepoints, see
2468 the "New remote packets" section below.
2470 * Better reconstruction of tracepoints after disconnected tracing
2472 GDB will attempt to download the original source form of tracepoint
2473 definitions when starting a trace run, and then will upload these
2474 upon reconnection to the target, resulting in a more accurate
2475 reconstruction of the tracepoints that are in use on the target.
2479 You can now exercise direct control over the ways that GDB can
2480 affect your program. For instance, you can disallow the setting of
2481 breakpoints, so that the program can run continuously (assuming
2482 non-stop mode). In addition, the "observer" variable is available
2483 to switch all of the different controls; in observer mode, GDB
2484 cannot affect the target's behavior at all, which is useful for
2485 tasks like diagnosing live systems in the field.
2487 * The new convenience variable $_thread holds the number of the
2490 * New remote packets
2494 Return the address of the Windows Thread Information Block of a given thread.
2498 In response to several of the tracepoint packets, the target may now
2499 also respond with a number of intermediate `qRelocInsn' request
2500 packets before the final result packet, to have GDB handle
2501 relocating an instruction to execute at a different address. This
2502 is particularly useful for stubs that support fast tracepoints. GDB
2503 reports support for this feature in the qSupported packet.
2507 List static tracepoint markers in the target program.
2511 List static tracepoint markers at a given address in the target
2514 qXfer:statictrace:read
2516 Read the static trace data collected (by a `collect $_sdata'
2517 tracepoint action). The remote stub reports support for this packet
2518 to gdb's qSupported query.
2522 Send the current settings of GDB's permission flags.
2526 Send part of the source (textual) form of a tracepoint definition,
2527 which includes location, conditional, and action list.
2529 * The source command now accepts a -s option to force searching for the
2530 script in the source search path even if the script name specifies
2533 * New features in the GDB remote stub, GDBserver
2535 - GDBserver now support tracepoints (including fast tracepoints, and
2536 static tracepoints). The feature is currently supported by the
2537 i386-linux and amd64-linux builds. See the "Tracepoints support
2538 in gdbserver" section in the manual for more information.
2540 GDBserver JIT compiles the tracepoint's conditional agent
2541 expression bytecode into native code whenever possible for low
2542 overhead dynamic tracepoints conditionals. For such tracepoints,
2543 an expression that examines program state is evaluated when the
2544 tracepoint is reached, in order to determine whether to capture
2545 trace data. If the condition is simple and false, processing the
2546 tracepoint finishes very quickly and no data is gathered.
2548 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2549 for static tracepoints support.
2551 - GDBserver now supports x86_64 Windows 64-bit debugging.
2553 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2554 it understands register description.
2556 * The --batch flag now disables pagination and queries.
2558 * X86 general purpose registers
2560 GDB now supports reading/writing byte, word and double-word x86
2561 general purpose registers directly. This means you can use, say,
2562 $ah or $ax to refer, respectively, to the byte register AH and
2563 16-bit word register AX that are actually portions of the 32-bit
2564 register EAX or 64-bit register RAX.
2566 * The `commands' command now accepts a range of breakpoints to modify.
2567 A plain `commands' following a command that creates multiple
2568 breakpoints affects all the breakpoints set by that command. This
2569 applies to breakpoints set by `rbreak', and also applies when a
2570 single `break' command creates multiple breakpoints (e.g.,
2571 breakpoints on overloaded c++ functions).
2573 * The `rbreak' command now accepts a filename specification as part of
2574 its argument, limiting the functions selected by the regex to those
2575 in the specified file.
2577 * Support for remote debugging Windows and SymbianOS shared libraries
2578 from Unix hosts has been improved. Non Windows GDB builds now can
2579 understand target reported file names that follow MS-DOS based file
2580 system semantics, such as file names that include drive letters and
2581 use the backslash character as directory separator. This makes it
2582 possible to transparently use the "set sysroot" and "set
2583 solib-search-path" on Unix hosts to point as host copies of the
2584 target's shared libraries. See the new command "set
2585 target-file-system-kind" described below, and the "Commands to
2586 specify files" section in the user manual for more information.
2590 eval template, expressions...
2591 Convert the values of one or more expressions under the control
2592 of the string template to a command line, and call it.
2594 set target-file-system-kind unix|dos-based|auto
2595 show target-file-system-kind
2596 Set or show the assumed file system kind for target reported file
2599 save breakpoints <filename>
2600 Save all current breakpoint definitions to a file suitable for use
2601 in a later debugging session. To read the saved breakpoint
2602 definitions, use the `source' command.
2604 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2607 info static-tracepoint-markers
2608 Display information about static tracepoint markers in the target.
2610 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2611 Define a static tracepoint by probing a marker at the given
2612 function, line, address, or marker ID.
2616 Enable and disable observer mode.
2618 set may-write-registers on|off
2619 set may-write-memory on|off
2620 set may-insert-breakpoints on|off
2621 set may-insert-tracepoints on|off
2622 set may-insert-fast-tracepoints on|off
2623 set may-interrupt on|off
2624 Set individual permissions for GDB effects on the target. Note that
2625 some of these settings can have undesirable or surprising
2626 consequences, particularly when changed in the middle of a session.
2627 For instance, disabling the writing of memory can prevent
2628 breakpoints from being inserted, cause single-stepping to fail, or
2629 even crash your program, if you disable after breakpoints have been
2630 inserted. However, GDB should not crash.
2632 set record memory-query on|off
2633 show record memory-query
2634 Control whether to stop the inferior if memory changes caused
2635 by an instruction cannot be recorded.
2640 The disassemble command now supports "start,+length" form of two arguments.
2644 ** GDB now provides a new directory location, called the python directory,
2645 where Python scripts written for GDB can be installed. The location
2646 of that directory is <data-directory>/python, where <data-directory>
2647 is the GDB data directory. For more details, see section `Scripting
2648 GDB using Python' in the manual.
2650 ** The GDB Python API now has access to breakpoints, symbols, symbol
2651 tables, program spaces, inferiors, threads and frame's code blocks.
2652 Additionally, GDB Parameters can now be created from the API, and
2653 manipulated via set/show in the CLI.
2655 ** New functions gdb.target_charset, gdb.target_wide_charset,
2656 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2658 ** New exception gdb.GdbError.
2660 ** Pretty-printers are now also looked up in the current program space.
2662 ** Pretty-printers can now be individually enabled and disabled.
2664 ** GDB now looks for names of Python scripts to auto-load in a
2665 special section named `.debug_gdb_scripts', in addition to looking
2666 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2668 * Tracepoint actions were unified with breakpoint commands. In particular,
2669 there are no longer differences in "info break" output for breakpoints and
2670 tracepoints and the "commands" command can be used for both tracepoints and
2671 regular breakpoints.
2675 ARM Symbian arm*-*-symbianelf*
2677 * D language support.
2678 GDB now supports debugging programs written in the D programming
2681 * GDB now supports the extended ptrace interface for PowerPC which is
2682 available since Linux kernel version 2.6.34. This automatically enables
2683 any hardware breakpoints and additional hardware watchpoints available in
2684 the processor. The old ptrace interface exposes just one hardware
2685 watchpoint and no hardware breakpoints.
2687 * GDB is now able to use the Data Value Compare (DVC) register available on
2688 embedded PowerPC processors to implement in hardware simple watchpoint
2689 conditions of the form:
2691 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2693 This works in native GDB running on Linux kernels with the extended ptrace
2694 interface mentioned above.
2696 *** Changes in GDB 7.1
2700 ** Namespace Support
2702 GDB now supports importing of namespaces in C++. This enables the
2703 user to inspect variables from imported namespaces. Support for
2704 namepace aliasing has also been added. So, if a namespace is
2705 aliased in the current scope (e.g. namepace C=A; ) the user can
2706 print variables using the alias (e.g. (gdb) print C::x).
2710 All known bugs relating to the printing of virtual base class were
2711 fixed. It is now possible to call overloaded static methods using a
2716 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2717 and reinterpret_cast<> are now handled by the C++ expression parser.
2721 Xilinx MicroBlaze microblaze-*-*
2726 Xilinx MicroBlaze microblaze
2729 * Multi-program debugging.
2731 GDB now has support for multi-program (a.k.a. multi-executable or
2732 multi-exec) debugging. This allows for debugging multiple inferiors
2733 simultaneously each running a different program under the same GDB
2734 session. See "Debugging Multiple Inferiors and Programs" in the
2735 manual for more information. This implied some user visible changes
2736 in the multi-inferior support. For example, "info inferiors" now
2737 lists inferiors that are not running yet or that have exited
2738 already. See also "New commands" and "New options" below.
2740 * New tracing features
2742 GDB's tracepoint facility now includes several new features:
2744 ** Trace state variables
2746 GDB tracepoints now include support for trace state variables, which
2747 are variables managed by the target agent during a tracing
2748 experiment. They are useful for tracepoints that trigger each
2749 other, so for instance one tracepoint can count hits in a variable,
2750 and then a second tracepoint has a condition that is true when the
2751 count reaches a particular value. Trace state variables share the
2752 $-syntax of GDB convenience variables, and can appear in both
2753 tracepoint actions and condition expressions. Use the "tvariable"
2754 command to create, and "info tvariables" to view; see "Trace State
2755 Variables" in the manual for more detail.
2759 GDB now includes an option for defining fast tracepoints, which
2760 targets may implement more efficiently, such as by installing a jump
2761 into the target agent rather than a trap instruction. The resulting
2762 speedup can be by two orders of magnitude or more, although the
2763 tradeoff is that some program locations on some target architectures
2764 might not allow fast tracepoint installation, for instance if the
2765 instruction to be replaced is shorter than the jump. To request a
2766 fast tracepoint, use the "ftrace" command, with syntax identical to
2767 the regular trace command.
2769 ** Disconnected tracing
2771 It is now possible to detach GDB from the target while it is running
2772 a trace experiment, then reconnect later to see how the experiment
2773 is going. In addition, a new variable disconnected-tracing lets you
2774 tell the target agent whether to continue running a trace if the
2775 connection is lost unexpectedly.
2779 GDB now has the ability to save the trace buffer into a file, and
2780 then use that file as a target, similarly to you can do with
2781 corefiles. You can select trace frames, print data that was
2782 collected in them, and use tstatus to display the state of the
2783 tracing run at the moment that it was saved. To create a trace
2784 file, use "tsave <filename>", and to use it, do "target tfile
2787 ** Circular trace buffer
2789 You can ask the target agent to handle the trace buffer as a
2790 circular buffer, discarding the oldest trace frames to make room for
2791 newer ones, by setting circular-trace-buffer to on. This feature may
2792 not be available for all target agents.
2797 The disassemble command, when invoked with two arguments, now requires
2798 the arguments to be comma-separated.
2801 The info variables command now displays variable definitions. Files
2802 which only declare a variable are not shown.
2805 The source command is now capable of sourcing Python scripts.
2806 This feature is dependent on the debugger being build with Python
2809 Related to this enhancement is also the introduction of a new command
2810 "set script-extension" (see below).
2812 * New commands (for set/show, see "New options" below)
2814 record save [<FILENAME>]
2815 Save a file (in core file format) containing the process record
2816 execution log for replay debugging at a later time.
2818 record restore <FILENAME>
2819 Restore the process record execution log that was saved at an
2820 earlier time, for replay debugging.
2822 add-inferior [-copies <N>] [-exec <FILENAME>]
2825 clone-inferior [-copies <N>] [ID]
2826 Make a new inferior ready to execute the same program another
2827 inferior has loaded.
2832 maint info program-spaces
2833 List the program spaces loaded into GDB.
2835 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2836 show remote interrupt-sequence
2837 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2838 as the sequence to the remote target in order to interrupt the execution.
2839 Ctrl-C is a default. Some system prefers BREAK which is high level of
2840 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2841 Magic SysRq g. It is BREAK signal and character 'g'.
2843 set remote interrupt-on-connect [on | off]
2844 show remote interrupt-on-connect
2845 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2846 remote target when gdb connects to it. This is needed when you debug
2849 set remotebreak [on | off]
2851 Deprecated. Use "set/show remote interrupt-sequence" instead.
2853 tvariable $NAME [ = EXP ]
2854 Create or modify a trace state variable.
2857 List trace state variables and their values.
2859 delete tvariable $NAME ...
2860 Delete one or more trace state variables.
2863 Evaluate the given expressions without collecting anything into the
2864 trace buffer. (Valid in tracepoint actions only.)
2866 ftrace FN / FILE:LINE / *ADDR
2867 Define a fast tracepoint at the given function, line, or address.
2869 * New expression syntax
2871 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2872 GDB now parses 0b101010 identically with 42.
2876 set follow-exec-mode new|same
2877 show follow-exec-mode
2878 Control whether GDB reuses the same inferior across an exec call or
2879 creates a new one. This is useful to be able to restart the old
2880 executable after the inferior having done an exec call.
2882 set default-collect EXPR, ...
2883 show default-collect
2884 Define a list of expressions to be collected at each tracepoint.
2885 This is a useful way to ensure essential items are not overlooked,
2886 such as registers or a critical global variable.
2888 set disconnected-tracing
2889 show disconnected-tracing
2890 If set to 1, the target is instructed to continue tracing if it
2891 loses its connection to GDB. If 0, the target is to stop tracing
2894 set circular-trace-buffer
2895 show circular-trace-buffer
2896 If set to on, the target is instructed to use a circular trace buffer
2897 and discard the oldest trace frames instead of stopping the trace due
2898 to a full trace buffer. If set to off, the trace stops when the buffer
2899 fills up. Some targets may not support this.
2901 set script-extension off|soft|strict
2902 show script-extension
2903 If set to "off", the debugger does not perform any script language
2904 recognition, and all sourced files are assumed to be GDB scripts.
2905 If set to "soft" (the default), files are sourced according to
2906 filename extension, falling back to GDB scripts if the first
2908 If set to "strict", files are sourced according to filename extension.
2910 set ada trust-PAD-over-XVS on|off
2911 show ada trust-PAD-over-XVS
2912 If off, activate a workaround against a bug in the debugging information
2913 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2914 the GCC sources for more information about the GNAT encoding and
2915 PAD types in particular). It is always safe to set this option to
2916 off, but this introduces a slight performance penalty. The default
2919 * Python API Improvements
2921 ** GDB provides the new class gdb.LazyString. This is useful in
2922 some pretty-printing cases. The new method gdb.Value.lazy_string
2923 provides a simple way to create objects of this type.
2925 ** The fields returned by gdb.Type.fields now have an
2926 `is_base_class' attribute.
2928 ** The new method gdb.Type.range returns the range of an array type.
2930 ** The new method gdb.parse_and_eval can be used to parse and
2931 evaluate an expression.
2933 * New remote packets
2936 Define a trace state variable.
2939 Get the current value of a trace state variable.
2942 Set desired tracing behavior upon disconnection.
2945 Set the trace buffer to be linear or circular.
2948 Get data about the tracepoints currently in use.
2952 Process record now works correctly with hardware watchpoints.
2954 Multiple bug fixes have been made to the mips-irix port, making it
2955 much more reliable. In particular:
2956 - Debugging threaded applications is now possible again. Previously,
2957 GDB would hang while starting the program, or while waiting for
2958 the program to stop at a breakpoint.
2959 - Attaching to a running process no longer hangs.
2960 - An error occurring while loading a core file has been fixed.
2961 - Changing the value of the PC register now works again. This fixes
2962 problems observed when using the "jump" command, or when calling
2963 a function from GDB, or even when assigning a new value to $pc.
2964 - With the "finish" and "return" commands, the return value for functions
2965 returning a small array is now correctly printed.
2966 - It is now possible to break on shared library code which gets executed
2967 during a shared library init phase (code executed while executing
2968 their .init section). Previously, the breakpoint would have no effect.
2969 - GDB is now able to backtrace through the signal handler for
2970 non-threaded programs.
2972 PIE (Position Independent Executable) programs debugging is now supported.
2973 This includes debugging execution of PIC (Position Independent Code) shared
2974 libraries although for that, it should be possible to run such libraries as an
2977 *** Changes in GDB 7.0
2979 * GDB now has an interface for JIT compilation. Applications that
2980 dynamically generate code can create symbol files in memory and register
2981 them with GDB. For users, the feature should work transparently, and
2982 for JIT developers, the interface is documented in the GDB manual in the
2983 "JIT Compilation Interface" chapter.
2985 * Tracepoints may now be conditional. The syntax is as for
2986 breakpoints; either an "if" clause appended to the "trace" command,
2987 or the "condition" command is available. GDB sends the condition to
2988 the target for evaluation using the same bytecode format as is used
2989 for tracepoint actions.
2991 * The disassemble command now supports: an optional /r modifier, print the
2992 raw instructions in hex as well as in symbolic form, and an optional /m
2993 modifier to print mixed source+assembly.
2995 * Process record and replay
2997 In a architecture environment that supports ``process record and
2998 replay'', ``process record and replay'' target can record a log of
2999 the process execution, and replay it with both forward and reverse
3002 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3003 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3004 set execution-direction {forward|reverse}, for targets that support
3007 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3008 feature is available with a native GDB running on kernel version
3011 * GDB now has support for multi-byte and wide character sets on the
3012 target. Strings whose character type is wchar_t, char16_t, or
3013 char32_t are now correctly printed. GDB supports wide- and unicode-
3014 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3015 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3016 `printf'. This feature requires iconv to work properly; if your
3017 system does not have a working iconv, GDB can use GNU libiconv. See
3018 the installation instructions for more information.
3020 * GDB now supports automatic retrieval of shared library files from
3021 remote targets. To use this feature, specify a system root that begins
3022 with the `remote:' prefix, either via the `set sysroot' command or via
3023 the `--with-sysroot' configure-time option.
3025 * "info sharedlibrary" now takes an optional regex of libraries to show,
3026 and it now reports if a shared library has no debugging information.
3028 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3029 now complete on file names.
3031 * When completing in expressions, gdb will attempt to limit
3032 completions to allowable structure or union fields, where appropriate.
3033 For instance, consider:
3035 # struct example { int f1; double f2; };
3036 # struct example variable;
3039 If the user types TAB at the end of this command line, the available
3040 completions will be "f1" and "f2".
3042 * Inlined functions are now supported. They show up in backtraces, and
3043 the "step", "next", and "finish" commands handle them automatically.
3045 * GDB now supports the token-splicing (##) and stringification (#)
3046 operators when expanding macros. It also supports variable-arity
3049 * GDB now supports inspecting extra signal information, exported by
3050 the new $_siginfo convenience variable. The feature is currently
3051 implemented on linux ARM, i386 and amd64.
3053 * GDB can now display the VFP floating point registers and NEON vector
3054 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3055 can provide these registers (requires Linux 2.6.30 or later). Remote
3056 and simulator targets may also provide them.
3058 * New remote packets
3061 Search memory for a sequence of bytes.
3064 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3065 operation over reliable transport links. Use of this packet is
3066 controlled by the `set remote noack-packet' command.
3069 Kill the process with the specified process ID. Use this in preference
3070 to `k' when multiprocess protocol extensions are supported.
3073 Obtains additional operating system information
3077 Read or write additional signal information.
3079 * Removed remote protocol undocumented extension
3081 An undocumented extension to the remote protocol's `S' stop reply
3082 packet that permited the stub to pass a process id was removed.
3083 Remote servers should use the `T' stop reply packet instead.
3085 * GDB now supports multiple function calling conventions according to the
3086 DWARF-2 DW_AT_calling_convention function attribute.
3088 * The SH target utilizes the aforementioned change to distinguish between gcc
3089 and Renesas calling convention. It also adds the new CLI commands
3090 `set/show sh calling-convention'.
3092 * GDB can now read compressed debug sections, as produced by GNU gold
3093 with the --compress-debug-sections=zlib flag.
3095 * 64-bit core files are now supported on AIX.
3097 * Thread switching is now supported on Tru64.
3099 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3100 which will be allocated using malloc later in program execution.
3102 * The qXfer:libraries:read remote procotol packet now allows passing a
3103 list of section offsets.
3105 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3106 conditions handling signals delivered during attach or thread creation
3107 have also been fixed.
3109 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3110 From the user's standpoint, all unqualified instances of True and False
3111 are treated as the standard definitions, regardless of context.
3113 * GDB now parses C++ symbol and type names more flexibly. For
3116 template<typename T> class C { };
3119 GDB will now correctly handle all of:
3121 ptype C<char const *>
3122 ptype C<char const*>
3123 ptype C<const char *>
3124 ptype C<const char*>
3126 * New features in the GDB remote stub, gdbserver
3128 - The "--wrapper" command-line argument tells gdbserver to use a
3129 wrapper program to launch programs for debugging.
3131 - On PowerPC and S/390 targets, it is now possible to use a single
3132 gdbserver executable to debug both 32-bit and 64-bit programs.
3133 (This requires gdbserver itself to be built as a 64-bit executable.)
3135 - gdbserver uses the new noack protocol mode for TCP connections to
3136 reduce communications latency, if also supported and enabled in GDB.
3138 - Support for the sparc64-linux-gnu target is now included in
3141 - The amd64-linux build of gdbserver now supports debugging both
3142 32-bit and 64-bit programs.
3144 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3145 now support hardware watchpoints, and will use them automatically
3150 GDB now has support for scripting using Python. Whether this is
3151 available is determined at configure time.
3153 New GDB commands can now be written in Python.
3155 * Ada tasking support
3157 Ada tasks can now be inspected in GDB. The following commands have
3161 Print the list of Ada tasks.
3163 Print detailed information about task number N.
3165 Print the task number of the current task.
3167 Switch the context of debugging to task number N.
3169 * Support for user-defined prefixed commands. The "define" command can
3170 add new commands to existing prefixes, e.g. "target".
3172 * Multi-inferior, multi-process debugging.
3174 GDB now has generalized support for multi-inferior debugging. See
3175 "Debugging Multiple Inferiors" in the manual for more information.
3176 Although availability still depends on target support, the command
3177 set is more uniform now. The GNU/Linux specific multi-forks support
3178 has been migrated to this new framework. This implied some user
3179 visible changes; see "New commands" and also "Removed commands"
3182 * Target descriptions can now describe the target OS ABI. See the
3183 "Target Description Format" section in the user manual for more
3186 * Target descriptions can now describe "compatible" architectures
3187 to indicate that the target can execute applications for a different
3188 architecture in addition to those for the main target architecture.
3189 See the "Target Description Format" section in the user manual for
3192 * Multi-architecture debugging.
3194 GDB now includes general supports for debugging applications on
3195 hybrid systems that use more than one single processor architecture
3196 at the same time. Each such hybrid architecture still requires
3197 specific support to be added. The only hybrid architecture supported
3198 in this version of GDB is the Cell Broadband Engine.
3200 * GDB now supports integrated debugging of Cell/B.E. applications that
3201 use both the PPU and SPU architectures. To enable support for hybrid
3202 Cell/B.E. debugging, you need to configure GDB to support both the
3203 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3204 --enable-targets configure option.
3206 * Non-stop mode debugging.
3208 For some targets, GDB now supports an optional mode of operation in
3209 which you can examine stopped threads while other threads continue
3210 to execute freely. This is referred to as non-stop mode, with the
3211 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3212 section in the user manual for more information.
3214 To be able to support remote non-stop debugging, a remote stub needs
3215 to implement the non-stop mode remote protocol extensions, as
3216 described in the "Remote Non-Stop" section of the user manual. The
3217 GDB remote stub, gdbserver, has been adjusted to support these
3218 extensions on linux targets.
3220 * New commands (for set/show, see "New options" below)
3222 catch syscall [NAME(S) | NUMBER(S)]
3223 Catch system calls. Arguments, which should be names of system
3224 calls or their numbers, mean catch only those syscalls. Without
3225 arguments, every syscall will be caught. When the inferior issues
3226 any of the specified syscalls, GDB will stop and announce the system
3227 call, both when it is called and when its call returns. This
3228 feature is currently available with a native GDB running on the
3229 Linux Kernel, under the following architectures: x86, x86_64,
3230 PowerPC and PowerPC64.
3232 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3234 Search memory for a sequence of bytes.
3236 maint set python print-stack
3237 maint show python print-stack
3238 Show a stack trace when an error is encountered in a Python script.
3241 Invoke CODE by passing it to the Python interpreter.
3246 These allow macros to be defined, undefined, and listed
3250 Show operating system information about processes.
3253 List the inferiors currently under GDB's control.
3256 Switch focus to inferior number NUM.
3259 Detach from inferior number NUM.
3262 Kill inferior number NUM.
3266 set spu stop-on-load
3267 show spu stop-on-load
3268 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3270 set spu auto-flush-cache
3271 show spu auto-flush-cache
3272 Control whether to automatically flush the software-managed cache
3273 during Cell/B.E. debugging.
3275 set sh calling-convention
3276 show sh calling-convention
3277 Control the calling convention used when calling SH target functions.
3280 show debug timestamp
3281 Control display of timestamps with GDB debugging output.
3283 set disassemble-next-line
3284 show disassemble-next-line
3285 Control display of disassembled source lines or instructions when
3288 set remote noack-packet
3289 show remote noack-packet
3290 Set/show the use of remote protocol QStartNoAckMode packet. See above
3291 under "New remote packets."
3293 set remote query-attached-packet
3294 show remote query-attached-packet
3295 Control use of remote protocol `qAttached' (query-attached) packet.
3297 set remote read-siginfo-object
3298 show remote read-siginfo-object
3299 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3302 set remote write-siginfo-object
3303 show remote write-siginfo-object
3304 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3307 set remote reverse-continue
3308 show remote reverse-continue
3309 Control use of remote protocol 'bc' (reverse-continue) packet.
3311 set remote reverse-step
3312 show remote reverse-step
3313 Control use of remote protocol 'bs' (reverse-step) packet.
3315 set displaced-stepping
3316 show displaced-stepping
3317 Control displaced stepping mode. Displaced stepping is a way to
3318 single-step over breakpoints without removing them from the debuggee.
3319 Also known as "out-of-line single-stepping".
3322 show debug displaced
3323 Control display of debugging info for displaced stepping.
3325 maint set internal-error
3326 maint show internal-error
3327 Control what GDB does when an internal error is detected.
3329 maint set internal-warning
3330 maint show internal-warning
3331 Control what GDB does when an internal warning is detected.
3336 Use a wrapper program to launch programs for debugging.
3338 set multiple-symbols (all|ask|cancel)
3339 show multiple-symbols
3340 The value of this variable can be changed to adjust the debugger behavior
3341 when an expression or a breakpoint location contains an ambiguous symbol
3342 name (an overloaded function name, for instance).
3344 set breakpoint always-inserted
3345 show breakpoint always-inserted
3346 Keep breakpoints always inserted in the target, as opposed to inserting
3347 them when resuming the target, and removing them when the target stops.
3348 This option can improve debugger performance on slow remote targets.
3350 set arm fallback-mode (arm|thumb|auto)
3351 show arm fallback-mode
3352 set arm force-mode (arm|thumb|auto)
3354 These commands control how ARM GDB determines whether instructions
3355 are ARM or Thumb. The default for both settings is auto, which uses
3356 the current CPSR value for instructions without symbols; previous
3357 versions of GDB behaved as if "set arm fallback-mode arm".
3359 set disable-randomization
3360 show disable-randomization
3361 Standalone programs run with the virtual address space randomization enabled
3362 by default on some platforms. This option keeps the addresses stable across
3363 multiple debugging sessions.
3367 Control whether other threads are stopped or not when some thread hits
3372 Requests that asynchronous execution is enabled in the target, if available.
3373 In this case, it's possible to resume target in the background, and interact
3374 with GDB while the target is running. "show target-async" displays the
3375 current state of asynchronous execution of the target.
3377 set target-wide-charset
3378 show target-wide-charset
3379 The target-wide-charset is the name of the character set that GDB
3380 uses when printing characters whose type is wchar_t.
3382 set tcp auto-retry (on|off)
3384 set tcp connect-timeout
3385 show tcp connect-timeout
3386 These commands allow GDB to retry failed TCP connections to a remote stub
3387 with a specified timeout period; this is useful if the stub is launched
3388 in parallel with GDB but may not be ready to accept connections immediately.
3390 set libthread-db-search-path
3391 show libthread-db-search-path
3392 Control list of directories which GDB will search for appropriate
3395 set schedule-multiple (on|off)
3396 show schedule-multiple
3397 Allow GDB to resume all threads of all processes or only threads of
3398 the current process.
3402 Use more aggressive caching for accesses to the stack. This improves
3403 performance of remote debugging (particularly backtraces) without
3404 affecting correctness.
3406 set interactive-mode (on|off|auto)
3407 show interactive-mode
3408 Control whether GDB runs in interactive mode (on) or not (off).
3409 When in interactive mode, GDB waits for the user to answer all
3410 queries. Otherwise, GDB does not wait and assumes the default
3411 answer. When set to auto (the default), GDB determines which
3412 mode to use based on the stdin settings.
3417 For program forks, this is replaced by the new more generic `info
3418 inferiors' command. To list checkpoints, you can still use the
3419 `info checkpoints' command, which was an alias for the `info forks'
3423 Replaced by the new `inferior' command. To switch between
3424 checkpoints, you can still use the `restart' command, which was an
3425 alias for the `fork' command.
3428 This is removed, since some targets don't have a notion of
3429 processes. To switch between processes, you can still use the
3430 `inferior' command using GDB's own inferior number.
3433 For program forks, this is replaced by the new more generic `kill
3434 inferior' command. To delete a checkpoint, you can still use the
3435 `delete checkpoint' command, which was an alias for the `delete
3439 For program forks, this is replaced by the new more generic `detach
3440 inferior' command. To detach a checkpoint, you can still use the
3441 `detach checkpoint' command, which was an alias for the `detach
3444 * New native configurations
3446 x86/x86_64 Darwin i[34567]86-*-darwin*
3448 x86_64 MinGW x86_64-*-mingw*
3452 Lattice Mico32 lm32-*
3453 x86 DICOS i[34567]86-*-dicos*
3454 x86_64 DICOS x86_64-*-dicos*
3457 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3458 (mingw32ce) debugging.
3464 These commands were actually not implemented on any target.
3466 *** Changes in GDB 6.8
3468 * New native configurations
3470 NetBSD/hppa hppa*-*netbsd*
3471 Xtensa GNU/Linux xtensa*-*-linux*
3475 NetBSD/hppa hppa*-*-netbsd*
3476 Xtensa GNU/Lunux xtensa*-*-linux*
3478 * Change in command line behavior -- corefiles vs. process ids.
3480 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3481 attaching to process NUMBER fails, GDB no longer attempts to open a
3482 core file named NUMBER. Attaching to a program using the -c option
3483 is no longer supported. Instead, use the '-p' or '--pid' options.
3485 * GDB can now be built as a native debugger for debugging Windows x86
3486 (mingw32) Portable Executable (PE) programs.
3488 * Pending breakpoints no longer change their number when their address
3491 * GDB now supports breakpoints with multiple locations,
3492 including breakpoints on C++ constructors, inside C++ templates,
3493 and in inlined functions.
3495 * GDB's ability to debug optimized code has been improved. GDB more
3496 accurately identifies function bodies and lexical blocks that occupy
3497 more than one contiguous range of addresses.
3499 * Target descriptions can now describe registers for PowerPC.
3501 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3502 registers on PowerPC targets.
3504 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3505 targets even when the libthread_db library is not available.
3507 * The GDB remote stub, gdbserver, now supports the new file transfer
3508 commands (remote put, remote get, and remote delete).
3510 * The GDB remote stub, gdbserver, now supports run and attach in
3511 extended-remote mode.
3513 * hppa*64*-*-hpux11* target broken
3514 The debugger is unable to start a program and fails with the following
3515 error: "Error trying to get information about dynamic linker".
3516 The gdb-6.7 release is also affected.
3518 * GDB now supports the --enable-targets= configure option to allow
3519 building a single GDB executable that supports multiple remote
3520 target architectures.
3522 * GDB now supports debugging C and C++ programs which use the
3523 Decimal Floating Point extension. In addition, the PowerPC target
3524 now has a set of pseudo-registers to inspect decimal float values
3525 stored in two consecutive float registers.
3527 * The -break-insert MI command can optionally create pending
3530 * Improved support for debugging Ada
3531 Many improvements to the Ada language support have been made. These
3533 - Better support for Ada2005 interface types
3534 - Improved handling of arrays and slices in general
3535 - Better support for Taft-amendment types
3536 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3538 - Improved command completion in Ada
3541 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3546 set print frame-arguments (all|scalars|none)
3547 show print frame-arguments
3548 The value of this variable can be changed to control which argument
3549 values should be printed by the debugger when displaying a frame.
3554 Transfer files to and from a remote target, and delete remote files.
3561 Transfer files to and from a remote target, and delete remote files.
3563 * New remote packets
3570 Open, close, read, write, and delete files on the remote system.
3573 Attach to an existing process on the remote system, in extended-remote
3577 Run a new process on the remote system, in extended-remote mode.
3579 *** Changes in GDB 6.7
3581 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3582 bfd, libiberty and opcodes, as revealed by static analysis donated by
3583 Coverity, Inc. (http://scan.coverity.com).
3585 * When looking up multiply-defined global symbols, GDB will now prefer the
3586 symbol definition in the current shared library if it was built using the
3587 -Bsymbolic linker option.
3589 * When the Text User Interface (TUI) is not configured, GDB will now
3590 recognize the -tui command-line option and print a message that the TUI
3593 * The GDB remote stub, gdbserver, now has lower overhead for high
3594 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3596 * GDB for MIPS targets now autodetects whether a remote target provides
3597 32-bit or 64-bit register values.
3599 * Support for C++ member pointers has been improved.
3601 * GDB now understands XML target descriptions, which specify the
3602 target's overall architecture. GDB can read a description from
3603 a local file or over the remote serial protocol.
3605 * Vectors of single-byte data use a new integer type which is not
3606 automatically displayed as character or string data.
3608 * The /s format now works with the print command. It displays
3609 arrays of single-byte integers and pointers to single-byte integers
3612 * Target descriptions can now describe target-specific registers,
3613 for architectures which have implemented the support (currently
3614 only ARM, M68K, and MIPS).
3616 * GDB and the GDB remote stub, gdbserver, now support the XScale
3619 * The GDB remote stub, gdbserver, has been updated to support
3620 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3621 has been rewritten to use the standard GDB remote protocol.
3623 * GDB can now step into C++ functions which are called through thunks.
3625 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3627 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3628 layout. It also supports a TextSeg= and DataSeg= response when only
3629 segment base addresses (rather than offsets) are available.
3631 * The /i format now outputs any trailing branch delay slot instructions
3632 immediately following the last instruction within the count specified.
3634 * The GDB remote protocol "T" stop reply packet now supports a
3635 "library" response. Combined with the new "qXfer:libraries:read"
3636 packet, this response allows GDB to debug shared libraries on targets
3637 where the operating system manages the list of loaded libraries (e.g.
3638 Windows and SymbianOS).
3640 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3641 (DLLs) on Windows and Windows CE targets.
3643 * GDB now supports a faster verification that a .debug file matches its binary
3644 according to its build-id signature, if the signature is present.
3650 Enable or disable hardware flow control (RTS/CTS) on the serial port
3651 when debugging using remote targets.
3653 set mem inaccessible-by-default
3654 show mem inaccessible-by-default
3655 If the target supplies a memory map, for instance via the remote
3656 protocol's "qXfer:memory-map:read" packet, setting this variable
3657 prevents GDB from accessing memory outside the memory map. This
3658 is useful for targets with memory mapped registers or which react
3659 badly to accesses of unmapped address space.
3661 set breakpoint auto-hw
3662 show breakpoint auto-hw
3663 If the target supplies a memory map, for instance via the remote
3664 protocol's "qXfer:memory-map:read" packet, setting this variable
3665 lets GDB use hardware breakpoints automatically for memory regions
3666 where it can not use software breakpoints. This covers both the
3667 "break" command and internal breakpoints used for other commands
3668 including "next" and "finish".
3671 catch exception unhandled
3672 Stop the program execution when Ada exceptions are raised.
3675 Stop the program execution when an Ada assertion failed.
3679 Set an alternate system root for target files. This is a more
3680 general version of "set solib-absolute-prefix", which is now
3681 an alias to "set sysroot".
3684 Provide extended SPU facility status information. This set of
3685 commands is available only when debugging the Cell/B.E. SPU
3688 * New native configurations
3690 OpenBSD/sh sh*-*openbsd*
3693 unset tdesc filename
3695 Use the specified local file as an XML target description, and do
3696 not query the target for its built-in description.
3700 OpenBSD/sh sh*-*-openbsd*
3701 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3702 Toshiba Media Processor mep-elf
3704 * New remote packets
3707 Ignore the specified signals; pass them directly to the debugged program
3708 without stopping other threads or reporting them to GDB.
3710 qXfer:features:read:
3711 Read an XML target description from the target, which describes its
3716 Read or write contents of an spufs file on the target system. These
3717 packets are available only on the Cell/B.E. SPU architecture.
3719 qXfer:libraries:read:
3720 Report the loaded shared libraries. Combined with new "T" packet
3721 response, this packet allows GDB to debug shared libraries on
3722 targets where the operating system manages the list of loaded
3723 libraries (e.g. Windows and SymbianOS).
3727 Support for these obsolete configurations has been removed.
3735 i[34567]86-*-lynxos*
3736 i[34567]86-*-netware*
3737 i[34567]86-*-sco3.2v5*
3738 i[34567]86-*-sco3.2v4*
3740 i[34567]86-*-sysv4.2*
3743 i[34567]86-*-unixware2*
3744 i[34567]86-*-unixware*
3753 * Other removed features
3760 Various m68k-only ROM monitors.
3767 Various Renesas ROM monitors and debugging interfaces for SH and
3772 Support for a Macraigor serial interface to on-chip debugging.
3773 GDB does not directly support the newer parallel or USB
3778 A debug information format. The predecessor to DWARF 2 and
3779 DWARF 3, which are still supported.
3781 Support for the HP aCC compiler on HP-UX/PA-RISC
3783 SOM-encapsulated symbolic debugging information, automatic
3784 invocation of pxdb, and the aCC custom C++ ABI. This does not
3785 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3786 with aCC can still be debugged on an assembly level.
3788 MIPS ".pdr" sections
3790 A MIPS-specific format used to describe stack frame layout
3791 in debugging information.
3795 GDB could work with an older version of Guile to debug
3796 the interpreter and Scheme programs running in it.
3798 set mips stack-arg-size
3799 set mips saved-gpreg-size
3801 Use "set mips abi" to control parameter passing for MIPS.
3803 *** Changes in GDB 6.6
3808 Cell Broadband Engine SPU spu-elf
3810 * GDB can now be configured as a cross-debugger targeting native Windows
3811 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3812 running on a Windows system over TCP/IP to debug Windows programs.
3814 * The GDB remote stub, gdbserver, has been updated to support Windows and
3815 Cygwin debugging. Both single-threaded and multi-threaded programs are
3818 * The "set trust-readonly-sections" command works again. This command was
3819 broken in GDB 6.3, 6.4, and 6.5.
3821 * The "load" command now supports writing to flash memory, if the remote
3822 stub provides the required support.
3824 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3825 longer requires symbolic debug information (e.g. DWARF-2).
3830 unset substitute-path
3831 show substitute-path
3832 Manage a list of substitution rules that GDB uses to rewrite the name
3833 of the directories where the sources are located. This can be useful
3834 for instance when the sources were moved to a different location
3835 between compilation and debugging.
3839 Print each CLI command as it is executed. Each command is prefixed with
3840 a number of `+' symbols representing the nesting depth.
3841 The source command now has a `-v' option to enable the same feature.
3845 The ARM Demon monitor support (RDP protocol, "target rdp").
3847 Kernel Object Display, an embedded debugging feature which only worked with
3848 an obsolete version of Cisco IOS.
3850 The 'set download-write-size' and 'show download-write-size' commands.
3852 * New remote packets
3855 Tell a stub about GDB client features, and request remote target features.
3856 The first feature implemented is PacketSize, which allows the target to
3857 specify the size of packets it can handle - to minimize the number of
3858 packets required and improve performance when connected to a remote
3862 Fetch an OS auxilliary vector from the remote stub. This packet is a
3863 more efficient replacement for qPart:auxv:read.
3865 qXfer:memory-map:read:
3866 Fetch a memory map from the remote stub, including information about
3867 RAM, ROM, and flash memory devices.
3872 Erase and program a flash memory device.
3874 * Removed remote packets
3877 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3878 used it, and only gdbserver implemented it.
3880 *** Changes in GDB 6.5
3884 Renesas M32C/M16C m32c-elf
3886 Morpho Technologies ms1 ms1-elf
3890 init-if-undefined Initialize a convenience variable, but
3891 only if it doesn't already have a value.
3893 The following commands are presently only implemented for native GNU/Linux:
3895 checkpoint Save a snapshot of the program state.
3897 restart <n> Return the program state to a
3898 previously saved state.
3900 info checkpoints List currently saved checkpoints.
3902 delete-checkpoint <n> Delete a previously saved checkpoint.
3904 set|show detach-on-fork Tell gdb whether to detach from a newly
3905 forked process, or to keep debugging it.
3907 info forks List forks of the user program that
3908 are available to be debugged.
3910 fork <n> Switch to debugging one of several
3911 forks of the user program that are
3912 available to be debugged.
3914 delete-fork <n> Delete a fork from the list of forks
3915 that are available to be debugged (and
3916 kill the forked process).
3918 detach-fork <n> Delete a fork from the list of forks
3919 that are available to be debugged (and
3920 allow the process to continue).
3924 Morpho Technologies ms2 ms1-elf
3926 * Improved Windows host support
3928 GDB now builds as a cross debugger hosted on i686-mingw32, including
3929 native console support, and remote communications using either
3930 network sockets or serial ports.
3932 * Improved Modula-2 language support
3934 GDB can now print most types in the Modula-2 syntax. This includes:
3935 basic types, set types, record types, enumerated types, range types,
3936 pointer types and ARRAY types. Procedure var parameters are correctly
3937 printed and hexadecimal addresses and character constants are also
3938 written in the Modula-2 syntax. Best results can be obtained by using
3939 GNU Modula-2 together with the -gdwarf-2 command line option.
3943 The ARM rdi-share module.
3945 The Netware NLM debug server.
3947 *** Changes in GDB 6.4
3949 * New native configurations
3951 OpenBSD/arm arm*-*-openbsd*
3952 OpenBSD/mips64 mips64-*-openbsd*
3956 Morpho Technologies ms1 ms1-elf
3958 * New command line options
3960 --batch-silent As for --batch, but totally silent.
3961 --return-child-result The debugger will exist with the same value
3962 the child (debugged) program exited with.
3963 --eval-command COMMAND, -ex COMMAND
3964 Execute a single GDB CLI command. This may be
3965 specified multiple times and in conjunction
3966 with the --command (-x) option.
3968 * Deprecated commands removed
3970 The following commands, that were deprecated in 2000, have been
3974 set|show arm disassembly-flavor set|show arm disassembler
3975 othernames set arm disassembler
3976 set|show remotedebug set|show debug remote
3977 set|show archdebug set|show debug arch
3978 set|show eventdebug set|show debug event
3981 * New BSD user-level threads support
3983 It is now possible to debug programs using the user-level threads
3984 library on OpenBSD and FreeBSD. Currently supported (target)
3987 FreeBSD/amd64 x86_64-*-freebsd*
3988 FreeBSD/i386 i386-*-freebsd*
3989 OpenBSD/i386 i386-*-openbsd*
3991 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3992 are not yet supported.
3994 * New support for Matsushita MN10300 w/sim added
3995 (Work in progress). mn10300-elf.
3997 * REMOVED configurations and files
3999 VxWorks and the XDR protocol *-*-vxworks
4000 Motorola MCORE mcore-*-*
4001 National Semiconductor NS32000 ns32k-*-*
4003 * New "set print array-indexes" command
4005 After turning this setting "on", GDB prints the index of each element
4006 when displaying arrays. The default is "off" to preserve the previous
4009 * VAX floating point support
4011 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4013 * User-defined command support
4015 In addition to using $arg0..$arg9 for argument passing, it is now possible
4016 to use $argc to determine now many arguments have been passed. See the
4017 section on user-defined commands in the user manual for more information.
4019 *** Changes in GDB 6.3:
4021 * New command line option
4023 GDB now accepts -l followed by a number to set the timeout for remote
4026 * GDB works with GCC -feliminate-dwarf2-dups
4028 GDB now supports a more compact representation of DWARF-2 debug
4029 information using DW_FORM_ref_addr references. These are produced
4030 by GCC with the option -feliminate-dwarf2-dups and also by some
4031 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4032 to use -feliminate-dwarf2-dups.
4034 * Internationalization
4036 When supported by the host system, GDB will be built with
4037 internationalization (libintl). The task of marking up the sources is
4038 continued, we're looking forward to our first translation.
4042 Initial support for debugging programs compiled with the GNAT
4043 implementation of the Ada programming language has been integrated
4044 into GDB. In this release, support is limited to expression evaluation.
4046 * New native configurations
4048 GNU/Linux/m32r m32r-*-linux-gnu
4052 GDB's remote protocol now includes support for the 'p' packet. This
4053 packet is used to fetch individual registers from a remote inferior.
4055 * END-OF-LIFE registers[] compatibility module
4057 GDB's internal register infrastructure has been completely rewritten.
4058 The new infrastructure making possible the implementation of key new
4059 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4062 GDB 6.3 will be the last release to include the the registers[]
4063 compatibility module that allowed out-of-date configurations to
4064 continue to work. This change directly impacts the following
4074 powerpc bdm protocol
4076 Unless there is activity to revive these configurations, they will be
4077 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4079 * OBSOLETE configurations and files
4081 Configurations that have been declared obsolete in this release have
4082 been commented out. Unless there is activity to revive these
4083 configurations, the next release of GDB will have their sources
4084 permanently REMOVED.
4093 *** Changes in GDB 6.2.1:
4095 * MIPS `break main; run' gave an heuristic-fence-post warning
4097 When attempting to run even a simple program, a warning about
4098 heuristic-fence-post being hit would be reported. This problem has
4101 * MIPS IRIX 'long double' crashed GDB
4103 When examining a long double variable, GDB would get a segmentation
4104 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4105 IRIX long double values).
4109 A bug in the VAX stack code was causing problems with the "next"
4110 command. This problem has been fixed.
4112 *** Changes in GDB 6.2:
4114 * Fix for ``many threads''
4116 On GNU/Linux systems that use the NPTL threads library, a program
4117 rapidly creating and deleting threads would confuse GDB leading to the
4120 ptrace: No such process.
4121 thread_db_get_info: cannot get thread info: generic error
4123 This problem has been fixed.
4125 * "-async" and "-noasync" options removed.
4127 Support for the broken "-noasync" option has been removed (it caused
4130 * New ``start'' command.
4132 This command runs the program until the begining of the main procedure.
4134 * New BSD Kernel Data Access Library (libkvm) interface
4136 Using ``target kvm'' it is now possible to debug kernel core dumps and
4137 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4138 platforms. Currently supported (native-only) configurations are:
4140 FreeBSD/amd64 x86_64-*-freebsd*
4141 FreeBSD/i386 i?86-*-freebsd*
4142 NetBSD/i386 i?86-*-netbsd*
4143 NetBSD/m68k m68*-*-netbsd*
4144 NetBSD/sparc sparc-*-netbsd*
4145 OpenBSD/amd64 x86_64-*-openbsd*
4146 OpenBSD/i386 i?86-*-openbsd*
4147 OpenBSD/m68k m68*-openbsd*
4148 OpenBSD/sparc sparc-*-openbsd*
4150 * Signal trampoline code overhauled
4152 Many generic problems with GDB's signal handling code have been fixed.
4153 These include: backtraces through non-contiguous stacks; recognition
4154 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4155 call; backtrace through a signal trampoline; step into and out of
4156 signal handlers; and single-stepping in the signal trampoline.
4158 Please note that kernel bugs are a limiting factor here. These
4159 features have been shown to work on an s390 GNU/Linux system that
4160 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4162 * Cygwin support for DWARF 2 added.
4164 * New native configurations
4166 GNU/Linux/hppa hppa*-*-linux*
4167 OpenBSD/hppa hppa*-*-openbsd*
4168 OpenBSD/m68k m68*-*-openbsd*
4169 OpenBSD/m88k m88*-*-openbsd*
4170 OpenBSD/powerpc powerpc-*-openbsd*
4171 NetBSD/vax vax-*-netbsd*
4172 OpenBSD/vax vax-*-openbsd*
4174 * END-OF-LIFE frame compatibility module
4176 GDB's internal frame infrastructure has been completely rewritten.
4177 The new infrastructure making it possible to support key new features
4178 including DWARF 2 Call Frame Information. To aid in the task of
4179 migrating old configurations to this new infrastructure, a
4180 compatibility module, that allowed old configurations to continue to
4181 work, was also included.
4183 GDB 6.2 will be the last release to include this frame compatibility
4184 module. This change directly impacts the following configurations:
4194 Unless there is activity to revive these configurations, they will be
4195 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4197 * REMOVED configurations and files
4199 Sun 3, running SunOS 3 m68*-*-sunos3*
4200 Sun 3, running SunOS 4 m68*-*-sunos4*
4201 Sun 2, running SunOS 3 m68000-*-sunos3*
4202 Sun 2, running SunOS 4 m68000-*-sunos4*
4203 Motorola 680x0 running LynxOS m68*-*-lynxos*
4204 AT&T 3b1/Unix pc m68*-att-*
4205 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4206 decstation mips-dec-* mips-little-*
4207 riscos mips-*-riscos* mips-*-sysv*
4208 sonymips mips-sony-*
4209 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4211 *** Changes in GDB 6.1.1:
4213 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4215 The TUI (Text-mode User Interface) is now built as part of a default
4216 GDB configuration. It is enabled by either selecting the TUI with the
4217 command line option "-i=tui" or by running the separate "gdbtui"
4218 program. For more information on the TUI, see the manual "Debugging
4221 * Pending breakpoint support (also included in GDB 6.1)
4223 Support has been added to allow you to specify breakpoints in shared
4224 libraries that have not yet been loaded. If a breakpoint location
4225 cannot be found, and the "breakpoint pending" option is set to auto,
4226 GDB queries you if you wish to make the breakpoint pending on a future
4227 shared-library load. If and when GDB resolves the breakpoint symbol,
4228 the pending breakpoint is removed as one or more regular breakpoints
4231 Pending breakpoints are very useful for GCJ Java debugging.
4233 * Fixed ISO-C build problems
4235 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4236 non ISO-C code that stopped them being built using a more strict ISO-C
4237 compiler (e.g., IBM's C compiler).
4239 * Fixed build problem on IRIX 5
4241 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4242 wasn't able to compile compile on an IRIX 5 system.
4244 * Added execute permission to gdb/gdbserver/configure
4246 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4247 permission. This bug would cause configure to fail on a number of
4248 systems (Solaris, IRIX). Ref: server/519.
4250 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4252 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4253 has been updated to use constant array sizes.
4255 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4257 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4258 its generated DWARF Call Frame Info. This encoding was causing GDB to
4259 panic, that panic has been fixed. Ref: gdb/1628.
4261 * Fixed a problem when examining parameters in shared library code.
4263 When examining parameters in optimized shared library code generated
4264 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4265 not available''. GDB now correctly displays the variable's value.
4267 *** Changes in GDB 6.1:
4269 * Removed --with-mmalloc
4271 Support for the mmalloc memory manager has been removed, as it
4272 conflicted with the internal gdb byte cache.
4274 * Changes in AMD64 configurations
4276 The AMD64 target now includes the %cs and %ss registers. As a result
4277 the AMD64 remote protocol has changed; this affects the floating-point
4278 and SSE registers. If you rely on those registers for your debugging,
4279 you should upgrade gdbserver on the remote side.
4281 * Revised SPARC target
4283 The SPARC target has been completely revised, incorporating the
4284 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4285 support for LynxOS and SunOS 4 has been dropped. Calling functions
4286 from within GDB on operating systems with a non-executable stack
4287 (Solaris, OpenBSD) now works.
4291 GDB has a new C++ demangler which does a better job on the mangled
4292 names generated by current versions of g++. It also runs faster, so
4293 with this and other changes gdb should now start faster on large C++
4296 * DWARF 2 Location Expressions
4298 GDB support for location expressions has been extended to support function
4299 arguments and frame bases. Older versions of GDB could crash when they
4302 * C++ nested types and namespaces
4304 GDB's support for nested types and namespaces in C++ has been
4305 improved, especially if you use the DWARF 2 debugging format. (This
4306 is the default for recent versions of GCC on most platforms.)
4307 Specifically, if you have a class "Inner" defined within a class or
4308 namespace "Outer", then GDB realizes that the class's name is
4309 "Outer::Inner", not simply "Inner". This should greatly reduce the
4310 frequency of complaints about not finding RTTI symbols. In addition,
4311 if you are stopped at inside of a function defined within a namespace,
4312 GDB modifies its name lookup accordingly.
4314 * New native configurations
4316 NetBSD/amd64 x86_64-*-netbsd*
4317 OpenBSD/amd64 x86_64-*-openbsd*
4318 OpenBSD/alpha alpha*-*-openbsd*
4319 OpenBSD/sparc sparc-*-openbsd*
4320 OpenBSD/sparc64 sparc64-*-openbsd*
4322 * New debugging protocols
4324 M32R with SDI protocol m32r-*-elf*
4326 * "set prompt-escape-char" command deleted.
4328 The command "set prompt-escape-char" has been deleted. This command,
4329 and its very obscure effet on GDB's prompt, was never documented,
4330 tested, nor mentioned in the NEWS file.
4332 * OBSOLETE configurations and files
4334 Configurations that have been declared obsolete in this release have
4335 been commented out. Unless there is activity to revive these
4336 configurations, the next release of GDB will have their sources
4337 permanently REMOVED.
4339 Sun 3, running SunOS 3 m68*-*-sunos3*
4340 Sun 3, running SunOS 4 m68*-*-sunos4*
4341 Sun 2, running SunOS 3 m68000-*-sunos3*
4342 Sun 2, running SunOS 4 m68000-*-sunos4*
4343 Motorola 680x0 running LynxOS m68*-*-lynxos*
4344 AT&T 3b1/Unix pc m68*-att-*
4345 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4346 decstation mips-dec-* mips-little-*
4347 riscos mips-*-riscos* mips-*-sysv*
4348 sonymips mips-sony-*
4349 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4351 * REMOVED configurations and files
4353 SGI Irix-4.x mips-sgi-irix4 or iris4
4354 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4355 Z8000 simulator z8k-zilog-none or z8ksim
4356 Matsushita MN10200 w/simulator mn10200-*-*
4357 H8/500 simulator h8500-hitachi-hms or h8500hms
4358 HP/PA running BSD hppa*-*-bsd*
4359 HP/PA running OSF/1 hppa*-*-osf*
4360 HP/PA Pro target hppa*-*-pro*
4361 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4362 386BSD i[3456]86-*-bsd*
4363 Sequent family i[3456]86-sequent-sysv4*
4364 i[3456]86-sequent-sysv*
4365 i[3456]86-sequent-bsd*
4366 SPARC running LynxOS sparc-*-lynxos*
4367 SPARC running SunOS 4 sparc-*-sunos4*
4368 Tsqware Sparclet sparclet-*-*
4369 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4371 *** Changes in GDB 6.0:
4375 Support for debugging the Objective-C programming language has been
4376 integrated into GDB.
4378 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4380 DWARF 2's Call Frame Information makes available compiler generated
4381 information that more exactly describes the program's run-time stack.
4382 By using this information, GDB is able to provide more robust stack
4385 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4386 have been updated to use a new backtrace mechanism which includes
4387 DWARF 2 CFI support.
4391 GDB's remote protocol has been extended to include support for hosted
4392 file I/O (where the remote target uses GDB's file system). See GDB's
4393 remote protocol documentation for details.
4395 * All targets using the new architecture framework.
4397 All of GDB's targets have been updated to use the new internal
4398 architecture framework. The way is now open for future GDB releases
4399 to include cross-architecture native debugging support (i386 on amd64,
4402 * GNU/Linux's Thread Local Storage (TLS)
4404 GDB now includes support for for the GNU/Linux implementation of
4405 per-thread variables.
4407 * GNU/Linux's Native POSIX Thread Library (NPTL)
4409 GDB's thread code has been updated to work with either the new
4410 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4412 * Separate debug info.
4414 GDB, in conjunction with BINUTILS, now supports a mechanism for
4415 automatically loading debug information from a separate file. Instead
4416 of shipping full debug and non-debug versions of system libraries,
4417 system integrators can now instead ship just the stripped libraries
4418 and optional debug files.
4420 * DWARF 2 Location Expressions
4422 DWARF 2 Location Expressions allow the compiler to more completely
4423 describe the location of variables (even in optimized code) to the
4426 GDB now includes preliminary support for location expressions (support
4427 for DW_OP_piece is still missing).
4431 A number of long standing bugs that caused GDB to die while starting a
4432 Java application have been fixed. GDB's Java support is now
4433 considered "useable".
4435 * GNU/Linux support for fork, vfork, and exec.
4437 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4438 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4441 * GDB supports logging output to a file
4443 There are two new commands, "set logging" and "show logging", which can be
4444 used to capture GDB's output to a file.
4446 * The meaning of "detach" has changed for gdbserver
4448 The "detach" command will now resume the application, as documented. To
4449 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4452 * d10v, m68hc11 `regs' command deprecated
4454 The `info registers' command has been updated so that it displays the
4455 registers using a format identical to the old `regs' command.
4459 A new command, "maint set profile on/off", has been added. This command can
4460 be used to enable or disable profiling while running GDB, to profile a
4461 session or a set of commands. In addition there is a new configure switch,
4462 "--enable-profiling", which will cause GDB to be compiled with profiling
4463 data, for more informative profiling results.
4465 * Default MI syntax changed to "mi2".
4467 The default MI (machine interface) syntax, enabled by the command line
4468 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4469 "mi1", can be enabled by specifying the option "-i=mi1".
4471 Support for the original "mi0" syntax (included in GDB 5.0) has been
4474 Fix for gdb/192: removed extraneous space when displaying frame level.
4475 Fix for gdb/672: update changelist is now output in mi list format.
4476 Fix for gdb/702: a -var-assign that updates the value now shows up
4477 in a subsequent -var-update.
4479 * New native configurations.
4481 FreeBSD/amd64 x86_64-*-freebsd*
4483 * Multi-arched targets.
4485 HP/PA HPUX11 hppa*-*-hpux*
4486 Renesas M32R/D w/simulator m32r-*-elf*
4488 * OBSOLETE configurations and files
4490 Configurations that have been declared obsolete in this release have
4491 been commented out. Unless there is activity to revive these
4492 configurations, the next release of GDB will have their sources
4493 permanently REMOVED.
4495 Z8000 simulator z8k-zilog-none or z8ksim
4496 Matsushita MN10200 w/simulator mn10200-*-*
4497 H8/500 simulator h8500-hitachi-hms or h8500hms
4498 HP/PA running BSD hppa*-*-bsd*
4499 HP/PA running OSF/1 hppa*-*-osf*
4500 HP/PA Pro target hppa*-*-pro*
4501 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4502 Sequent family i[3456]86-sequent-sysv4*
4503 i[3456]86-sequent-sysv*
4504 i[3456]86-sequent-bsd*
4505 Tsqware Sparclet sparclet-*-*
4506 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4508 * REMOVED configurations and files
4511 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4512 IBM AIX PS/2 i[3456]86-*-aix
4513 i386 running Mach 3.0 i[3456]86-*-mach3*
4514 i386 running Mach i[3456]86-*-mach*
4515 i386 running OSF/1 i[3456]86-*osf1mk*
4516 HP/Apollo 68k Family m68*-apollo*-sysv*,
4518 m68*-hp-bsd*, m68*-hp-hpux*
4519 Argonaut Risc Chip (ARC) arc-*-*
4520 Mitsubishi D30V d30v-*-*
4521 Fujitsu FR30 fr30-*-elf*
4522 OS/9000 i[34]86-*-os9k
4523 I960 with MON960 i960-*-coff
4525 * MIPS $fp behavior changed
4527 The convenience variable $fp, for the MIPS, now consistently returns
4528 the address of the current frame's base. Previously, depending on the
4529 context, $fp could refer to either $sp or the current frame's base
4530 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4531 The GNU Source-Level Debugger''.
4533 *** Changes in GDB 5.3:
4535 * GNU/Linux shared library multi-threaded performance improved.
4537 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4538 `/proc', in preference to `ptrace' for memory reads. This may result
4539 in an improvement in the start-up time of multi-threaded, shared
4540 library applications when run under GDB. One GDB user writes: ``loads
4541 shared libs like mad''.
4543 * ``gdbserver'' now supports multi-threaded applications on some targets
4545 Support for debugging multi-threaded applications which use
4546 the GNU/Linux LinuxThreads package has been added for
4547 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4548 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4550 * GDB now supports C/C++ preprocessor macros.
4552 GDB now expands preprocessor macro invocations in C/C++ expressions,
4553 and provides various commands for showing macro definitions and how
4556 The new command `macro expand EXPRESSION' expands any macro
4557 invocations in expression, and shows the result.
4559 The new command `show macro MACRO-NAME' shows the definition of the
4560 macro named MACRO-NAME, and where it was defined.
4562 Most compilers don't include information about macros in the debugging
4563 information by default. In GCC 3.1, for example, you need to compile
4564 your program with the options `-gdwarf-2 -g3'. If the macro
4565 information is present in the executable, GDB will read it.
4567 * Multi-arched targets.
4569 DEC Alpha (partial) alpha*-*-*
4570 DEC VAX (partial) vax-*-*
4572 National Semiconductor NS32000 (partial) ns32k-*-*
4573 Motorola 68000 (partial) m68k-*-*
4574 Motorola MCORE mcore-*-*
4578 Fujitsu FRV architecture added by Red Hat frv*-*-*
4581 * New native configurations
4583 Alpha NetBSD alpha*-*-netbsd*
4584 SH NetBSD sh*-*-netbsdelf*
4585 MIPS NetBSD mips*-*-netbsd*
4586 UltraSPARC NetBSD sparc64-*-netbsd*
4588 * OBSOLETE configurations and files
4590 Configurations that have been declared obsolete in this release have
4591 been commented out. Unless there is activity to revive these
4592 configurations, the next release of GDB will have their sources
4593 permanently REMOVED.
4595 Mitsubishi D30V d30v-*-*
4596 OS/9000 i[34]86-*-os9k
4597 IBM AIX PS/2 i[3456]86-*-aix
4598 Fujitsu FR30 fr30-*-elf*
4599 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4600 Argonaut Risc Chip (ARC) arc-*-*
4601 i386 running Mach 3.0 i[3456]86-*-mach3*
4602 i386 running Mach i[3456]86-*-mach*
4603 i386 running OSF/1 i[3456]86-*osf1mk*
4604 HP/Apollo 68k Family m68*-apollo*-sysv*,
4606 m68*-hp-bsd*, m68*-hp-hpux*
4607 I960 with MON960 i960-*-coff
4609 * OBSOLETE languages
4611 CHILL, a Pascal like language used by telecommunications companies.
4613 * REMOVED configurations and files
4615 AMD 29k family via UDI a29k-amd-udi, udi29k
4616 A29K VxWorks a29k-*-vxworks
4617 AMD 29000 embedded, using EBMON a29k-none-none
4618 AMD 29000 embedded with COFF a29k-none-coff
4619 AMD 29000 embedded with a.out a29k-none-aout
4621 testsuite/gdb.hp/gdb.threads-hp/ directory
4623 * New command "set max-user-call-depth <nnn>"
4625 This command allows the user to limit the call depth of user-defined
4626 commands. The default is 1024.
4628 * Changes in FreeBSD/i386 native debugging.
4630 Support for the "generate-core-file" has been added.
4632 * New commands "dump", "append", and "restore".
4634 These commands allow data to be copied from target memory
4635 to a bfd-format or binary file (dump and append), and back
4636 from a file into memory (restore).
4638 * Improved "next/step" support on multi-processor Alpha Tru64.
4640 The previous single-step mechanism could cause unpredictable problems,
4641 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4642 of a software single-step mechanism prevents this.
4644 *** Changes in GDB 5.2.1:
4652 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4653 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4654 Fix, by Joel Brobecker imported from mainline.
4656 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4657 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4658 Fix, by Fred Fish, imported from mainline.
4660 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4661 Surprisingly enough, it works now.
4662 By Michal Ludvig, imported from mainline.
4664 i386 hardware watchpoint support:
4665 avoid misses on second run for some targets.
4666 By Pierre Muller, imported from mainline.
4668 *** Changes in GDB 5.2:
4670 * New command "set trust-readonly-sections on[off]".
4672 This command is a hint that tells gdb that read-only sections
4673 really are read-only (ie. that their contents will not change).
4674 In this mode, gdb will go to the object file rather than the
4675 target to read memory from read-only sections (such as ".text").
4676 This can be a significant performance improvement on some
4677 (notably embedded) targets.
4679 * New command "generate-core-file" (or "gcore").
4681 This new gdb command allows the user to drop a core file of the child
4682 process state at any time. So far it's been implemented only for
4683 GNU/Linux and Solaris, but should be relatively easily ported to other
4684 hosts. Argument is core file name (defaults to core.<pid>).
4686 * New command line option
4688 GDB now accepts --pid or -p followed by a process id.
4690 * Change in command line behavior -- corefiles vs. process ids.
4692 There is a subtle behavior in the way in which GDB handles
4693 command line arguments. The first non-flag argument is always
4694 a program to debug, but the second non-flag argument may either
4695 be a corefile or a process id. Previously, GDB would attempt to
4696 open the second argument as a corefile, and if that failed, would
4697 issue a superfluous error message and then attempt to attach it as
4698 a process. Now, if the second argument begins with a non-digit,
4699 it will be treated as a corefile. If it begins with a digit,
4700 GDB will attempt to attach it as a process, and if no such process
4701 is found, will then attempt to open it as a corefile.
4703 * Changes in ARM configurations.
4705 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4706 configuration is fully multi-arch.
4708 * New native configurations
4710 ARM NetBSD arm*-*-netbsd*
4711 x86 OpenBSD i[3456]86-*-openbsd*
4712 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4713 Sparc64 running FreeBSD sparc64-*-freebsd*
4717 Sanyo XStormy16 xstormy16-elf
4719 * OBSOLETE configurations and files
4721 Configurations that have been declared obsolete in this release have
4722 been commented out. Unless there is activity to revive these
4723 configurations, the next release of GDB will have their sources
4724 permanently REMOVED.
4726 AMD 29k family via UDI a29k-amd-udi, udi29k
4727 A29K VxWorks a29k-*-vxworks
4728 AMD 29000 embedded, using EBMON a29k-none-none
4729 AMD 29000 embedded with COFF a29k-none-coff
4730 AMD 29000 embedded with a.out a29k-none-aout
4732 testsuite/gdb.hp/gdb.threads-hp/ directory
4734 * REMOVED configurations and files
4736 TI TMS320C80 tic80-*-*
4738 PowerPC Solaris powerpcle-*-solaris*
4739 PowerPC Windows NT powerpcle-*-cygwin32
4740 PowerPC Netware powerpc-*-netware*
4741 Harris/CXUX m88k m88*-harris-cxux*
4742 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4743 ns32k-utek-sysv* ns32k-utek-*
4744 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4745 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4746 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4747 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4748 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4750 * Changes to command line processing
4752 The new `--args' feature can be used to specify command-line arguments
4753 for the inferior from gdb's command line.
4755 * Changes to key bindings
4757 There is a new `operate-and-get-next' function bound to `C-o'.
4759 *** Changes in GDB 5.1.1
4761 Fix compile problem on DJGPP.
4763 Fix a problem with floating-point registers on the i386 being
4766 Fix to stop GDB crashing on .debug_str debug info.
4768 Numerous documentation fixes.
4770 Numerous testsuite fixes.
4772 *** Changes in GDB 5.1:
4774 * New native configurations
4776 Alpha FreeBSD alpha*-*-freebsd*
4777 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4778 MIPS GNU/Linux mips*-*-linux*
4779 MIPS SGI Irix 6.x mips*-sgi-irix6*
4780 ia64 AIX ia64-*-aix*
4781 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4785 Motorola 68HC11 and 68HC12 m68hc11-elf
4787 UltraSparc running GNU/Linux sparc64-*-linux*
4789 * OBSOLETE configurations and files
4791 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4792 Harris/CXUX m88k m88*-harris-cxux*
4793 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4794 ns32k-utek-sysv* ns32k-utek-*
4795 TI TMS320C80 tic80-*-*
4797 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4798 PowerPC Solaris powerpcle-*-solaris*
4799 PowerPC Windows NT powerpcle-*-cygwin32
4800 PowerPC Netware powerpc-*-netware*
4801 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4802 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4803 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4804 Apple Macintosh (MPW) host N/A
4806 stuff.c (Program to stuff files into a specially prepared space in kdb)
4807 kdb-start.c (Main loop for the standalone kernel debugger)
4809 Configurations that have been declared obsolete in this release have
4810 been commented out. Unless there is activity to revive these
4811 configurations, the next release of GDB will have their sources
4812 permanently REMOVED.
4814 * REMOVED configurations and files
4816 Altos 3068 m68*-altos-*
4817 Convex c1-*-*, c2-*-*
4819 ARM RISCix arm-*-* (as host)
4823 * GDB has been converted to ISO C.
4825 GDB's source code has been converted to ISO C. In particular, the
4826 sources are fully protoized, and rely on standard headers being
4831 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4833 * The MI enabled by default.
4835 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4836 revised and enabled by default. Packages which use GDB as a debugging
4837 engine behind a UI or another front end are encouraged to switch to
4838 using the GDB/MI interface, instead of the old annotations interface
4839 which is now deprecated.
4841 * Support for debugging Pascal programs.
4843 GDB now includes support for debugging Pascal programs. The following
4844 main features are supported:
4846 - Pascal-specific data types such as sets;
4848 - automatic recognition of Pascal sources based on file-name
4851 - Pascal-style display of data types, variables, and functions;
4853 - a Pascal expression parser.
4855 However, some important features are not yet supported.
4857 - Pascal string operations are not supported at all;
4859 - there are some problems with boolean types;
4861 - Pascal type hexadecimal constants are not supported
4862 because they conflict with the internal variables format;
4864 - support for Pascal objects and classes is not full yet;
4866 - unlike Pascal, GDB is case-sensitive for symbol names.
4868 * Changes in completion.
4870 Commands such as `shell', `run' and `set args', which pass arguments
4871 to inferior programs, now complete on file names, similar to what
4872 users expect at the shell prompt.
4874 Commands which accept locations, such as `disassemble', `print',
4875 `breakpoint', `until', etc. now complete on filenames as well as
4876 program symbols. Thus, if you type "break foob TAB", and the source
4877 files linked into the programs include `foobar.c', that file name will
4878 be one of the candidates for completion. However, file names are not
4879 considered for completion after you typed a colon that delimits a file
4880 name from a name of a function in that file, as in "break foo.c:bar".
4882 `set demangle-style' completes on available demangling styles.
4884 * New platform-independent commands:
4886 It is now possible to define a post-hook for a command as well as a
4887 hook that runs before the command. For more details, see the
4888 documentation of `hookpost' in the GDB manual.
4890 * Changes in GNU/Linux native debugging.
4892 Support for debugging multi-threaded programs has been completely
4893 revised for all platforms except m68k and sparc. You can now debug as
4894 many threads as your system allows you to have.
4896 Attach/detach is supported for multi-threaded programs.
4898 Support for SSE registers was added for x86. This doesn't work for
4899 multi-threaded programs though.
4901 * Changes in MIPS configurations.
4903 Multi-arch support is enabled for all MIPS configurations.
4905 GDB can now be built as native debugger on SGI Irix 6.x systems for
4906 debugging n32 executables. (Debugging 64-bit executables is not yet
4909 * Unified support for hardware watchpoints in all x86 configurations.
4911 Most (if not all) native x86 configurations support hardware-assisted
4912 breakpoints and watchpoints in a unified manner. This support
4913 implements debug register sharing between watchpoints, which allows to
4914 put a virtually infinite number of watchpoints on the same address,
4915 and also supports watching regions up to 16 bytes with several debug
4918 The new maintenance command `maintenance show-debug-regs' toggles
4919 debugging print-outs in functions that insert, remove, and test
4920 watchpoints and hardware breakpoints.
4922 * Changes in the DJGPP native configuration.
4924 New command ``info dos sysinfo'' displays assorted information about
4925 the CPU, OS, memory, and DPMI server.
4927 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4928 display information about segment descriptors stored in GDT, LDT, and
4931 New commands ``info dos pde'' and ``info dos pte'' display entries
4932 from Page Directory and Page Tables (for now works with CWSDPMI only).
4933 New command ``info dos address-pte'' displays the Page Table entry for
4934 a given linear address.
4936 GDB can now pass command lines longer than 126 characters to the
4937 program being debugged (requires an update to the libdbg.a library
4938 which is part of the DJGPP development kit).
4940 DWARF2 debug info is now supported.
4942 It is now possible to `step' and `next' through calls to `longjmp'.
4944 * Changes in documentation.
4946 All GDB documentation was converted to GFDL, the GNU Free
4947 Documentation License.
4949 Tracepoints-related commands are now fully documented in the GDB
4952 TUI, the Text-mode User Interface, is now documented in the manual.
4954 Tracepoints-related commands are now fully documented in the GDB
4957 The "GDB Internals" manual now has an index. It also includes
4958 documentation of `ui_out' functions, GDB coding standards, x86
4959 hardware watchpoints, and memory region attributes.
4961 * GDB's version number moved to ``version.in''
4963 The Makefile variable VERSION has been replaced by the file
4964 ``version.in''. People creating GDB distributions should update the
4965 contents of this file.
4969 GUD support is now a standard part of the EMACS distribution.
4971 *** Changes in GDB 5.0:
4973 * Improved support for debugging FP programs on x86 targets
4975 Unified and much-improved support for debugging floating-point
4976 programs on all x86 targets. In particular, ``info float'' now
4977 displays the FP registers in the same format on all x86 targets, with
4978 greater level of detail.
4980 * Improvements and bugfixes in hardware-assisted watchpoints
4982 It is now possible to watch array elements, struct members, and
4983 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4984 on x86 targets no longer erroneously trigger when the address is
4987 * Improvements in the native DJGPP version of GDB
4989 The distribution now includes all the scripts and auxiliary files
4990 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4991 machines ``out of the box''.
4993 The DJGPP version can now debug programs that use signals. It is
4994 possible to catch signals that happened in the debuggee, deliver
4995 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4996 would kill the program being debugged.) Programs that hook hardware
4997 interrupts (keyboard, timer, etc.) can also be debugged.
4999 It is now possible to debug DJGPP programs that redirect their
5000 standard handles or switch them to raw (as opposed to cooked) mode, or
5001 even close them. The command ``run < foo > bar'' works as expected,
5002 and ``info terminal'' reports useful information about the debuggee's
5003 terminal, including raw/cooked mode, redirection, etc.
5005 The DJGPP version now uses termios functions for console I/O, which
5006 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5009 DOS-style file names with drive letters are now fully supported by
5012 It is now possible to debug DJGPP programs that switch their working
5013 directory. It is also possible to rerun the debuggee any number of
5014 times without restarting GDB; thus, you can use the same setup,
5015 breakpoints, etc. for many debugging sessions.
5017 * New native configurations
5019 ARM GNU/Linux arm*-*-linux*
5020 PowerPC GNU/Linux powerpc-*-linux*
5024 Motorola MCore mcore-*-*
5025 x86 VxWorks i[3456]86-*-vxworks*
5026 PowerPC VxWorks powerpc-*-vxworks*
5027 TI TMS320C80 tic80-*-*
5029 * OBSOLETE configurations
5031 Altos 3068 m68*-altos-*
5032 Convex c1-*-*, c2-*-*
5034 ARM RISCix arm-*-* (as host)
5037 Configurations that have been declared obsolete will be commented out,
5038 but the code will be left in place. If there is no activity to revive
5039 these configurations before the next release of GDB, the sources will
5040 be permanently REMOVED.
5042 * Gould support removed
5044 Support for the Gould PowerNode and NP1 has been removed.
5046 * New features for SVR4
5048 On SVR4 native platforms (such as Solaris), if you attach to a process
5049 without first loading a symbol file, GDB will now attempt to locate and
5050 load symbols from the running process's executable file.
5052 * Many C++ enhancements
5054 C++ support has been greatly improved. Overload resolution now works properly
5055 in almost all cases. RTTI support is on the way.
5057 * Remote targets can connect to a sub-program
5059 A popen(3) style serial-device has been added. This device starts a
5060 sub-process (such as a stand-alone simulator) and then communicates
5061 with that. The sub-program to run is specified using the syntax
5062 ``|<program> <args>'' vis:
5064 (gdb) set remotedebug 1
5065 (gdb) target extended-remote |mn10300-elf-sim program-args
5067 * MIPS 64 remote protocol
5069 A long standing bug in the mips64 remote protocol where by GDB
5070 expected certain 32 bit registers (ex SR) to be transfered as 32
5071 instead of 64 bits has been fixed.
5073 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5074 added to provide backward compatibility with older versions of GDB.
5076 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5078 The command ``set remotebinarydownload'' command has been replaced by
5079 ``set remote X-packet''. Other commands in ``set remote'' family
5080 include ``set remote P-packet''.
5082 * Breakpoint commands accept ranges.
5084 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5085 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5086 ``tracepoint passcount'' also accepts a range of tracepoints.
5088 * ``apropos'' command added.
5090 The ``apropos'' command searches through command names and
5091 documentation strings, printing out matches, making it much easier to
5092 try to find a command that does what you are looking for.
5096 A new machine oriented interface (MI) has been added to GDB. This
5097 interface is designed for debug environments running GDB as a separate
5098 process. This is part of the long term libGDB project. See the
5099 "GDB/MI" chapter of the GDB manual for further information. It can be
5100 enabled by configuring with:
5102 .../configure --enable-gdbmi
5104 *** Changes in GDB-4.18:
5106 * New native configurations
5108 HP-UX 10.20 hppa*-*-hpux10.20
5109 HP-UX 11.x hppa*-*-hpux11.0*
5110 M68K GNU/Linux m68*-*-linux*
5114 Fujitsu FR30 fr30-*-elf*
5115 Intel StrongARM strongarm-*-*
5116 Mitsubishi D30V d30v-*-*
5118 * OBSOLETE configurations
5120 Gould PowerNode, NP1 np1-*-*, pn-*-*
5122 Configurations that have been declared obsolete will be commented out,
5123 but the code will be left in place. If there is no activity to revive
5124 these configurations before the next release of GDB, the sources will
5125 be permanently REMOVED.
5129 As a compatibility experiment, GDB's source files buildsym.h and
5130 buildsym.c have been converted to pure standard C, no longer
5131 containing any K&R compatibility code. We believe that all systems in
5132 use today either come with a standard C compiler, or have a GCC port
5133 available. If this is not true, please report the affected
5134 configuration to bug-gdb@gnu.org immediately. See the README file for
5135 information about getting a standard C compiler if you don't have one
5140 GDB now uses readline 2.2.
5142 * set extension-language
5144 You can now control the mapping between filename extensions and source
5145 languages by using the `set extension-language' command. For instance,
5146 you can ask GDB to treat .c files as C++ by saying
5147 set extension-language .c c++
5148 The command `info extensions' lists all of the recognized extensions
5149 and their associated languages.
5151 * Setting processor type for PowerPC and RS/6000
5153 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5154 you can use the `set processor' command to specify what variant of the
5155 PowerPC family you are debugging. The command
5159 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5160 following PowerPC and RS6000 variants:
5162 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5163 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5165 403GC IBM PowerPC 403GC
5166 505 Motorola PowerPC 505
5167 860 Motorola PowerPC 860 or 850
5168 601 Motorola PowerPC 601
5169 602 Motorola PowerPC 602
5170 603 Motorola/IBM PowerPC 603 or 603e
5171 604 Motorola PowerPC 604 or 604e
5172 750 Motorola/IBM PowerPC 750 or 750
5174 At the moment, this command just tells GDB what to name the
5175 special-purpose processor registers. Since almost all the affected
5176 registers are inaccessible to user-level programs, this command is
5177 only useful for remote debugging in its present form.
5181 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5182 more extensive support for HP-UX. Added features include shared
5183 library support, kernel threads and hardware watchpoints for 11.00,
5184 support for HP's ANSI C and C++ compilers, and a compatibility mode
5185 for xdb and dbx commands.
5189 HP's donation includes the new concept of catchpoints, which is a
5190 generalization of the old catch command. On HP-UX, it is now possible
5191 to catch exec, fork, and vfork, as well as library loading.
5193 This means that the existing catch command has changed; its first
5194 argument now specifies the type of catch to be set up. See the
5195 output of "help catch" for a list of catchpoint types.
5197 * Debugging across forks
5199 On HP-UX, you can choose which process to debug when a fork() happens
5204 HP has donated a curses-based terminal user interface (TUI). To get
5205 it, build with --enable-tui. Although this can be enabled for any
5206 configuration, at present it only works for native HP debugging.
5208 * GDB remote protocol additions
5210 A new protocol packet 'X' that writes binary data is now available.
5211 Default behavior is to try 'X', then drop back to 'M' if the stub
5212 fails to respond. The settable variable `remotebinarydownload'
5213 allows explicit control over the use of 'X'.
5215 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5216 full 64-bit address. The command
5218 set remoteaddresssize 32
5220 can be used to revert to the old behaviour. For existing remote stubs
5221 the change should not be noticed, as the additional address information
5224 In order to assist in debugging stubs, you may use the maintenance
5225 command `packet' to send any text string to the stub. For instance,
5227 maint packet heythere
5229 sends the packet "$heythere#<checksum>". Note that it is very easy to
5230 disrupt a debugging session by sending the wrong packet at the wrong
5233 The compare-sections command allows you to compare section data on the
5234 target to what is in the executable file without uploading or
5235 downloading, by comparing CRC checksums.
5237 * Tracing can collect general expressions
5239 You may now collect general expressions at tracepoints. This requires
5240 further additions to the target-side stub; see tracepoint.c and
5241 doc/agentexpr.texi for further details.
5243 * mask-address variable for Mips
5245 For Mips targets, you may control the zeroing of the upper 32 bits of
5246 a 64-bit address by entering `set mask-address on'. This is mainly
5247 of interest to users of embedded R4xxx and R5xxx processors.
5249 * Higher serial baud rates
5251 GDB's serial code now allows you to specify baud rates 57600, 115200,
5252 230400, and 460800 baud. (Note that your host system may not be able
5253 to achieve all of these rates.)
5257 The i960 configuration now includes an initial implementation of a
5258 builtin simulator, contributed by Jim Wilson.
5261 *** Changes in GDB-4.17:
5263 * New native configurations
5265 Alpha GNU/Linux alpha*-*-linux*
5266 Unixware 2.x i[3456]86-unixware2*
5267 Irix 6.x mips*-sgi-irix6*
5268 PowerPC GNU/Linux powerpc-*-linux*
5269 PowerPC Solaris powerpcle-*-solaris*
5270 Sparc GNU/Linux sparc-*-linux*
5271 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5275 Argonaut Risc Chip (ARC) arc-*-*
5276 Hitachi H8/300S h8300*-*-*
5277 Matsushita MN10200 w/simulator mn10200-*-*
5278 Matsushita MN10300 w/simulator mn10300-*-*
5279 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5280 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5281 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5282 Mitsubishi D10V w/simulator d10v-*-*
5283 Mitsubishi M32R/D w/simulator m32r-*-elf*
5284 Tsqware Sparclet sparclet-*-*
5285 NEC V850 w/simulator v850-*-*
5287 * New debugging protocols
5289 ARM with RDI protocol arm*-*-*
5290 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5291 DDB and LSI variants of PMON protocol mips*-*-*
5292 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5293 PowerPC with SDS protocol powerpc{,le}-*-eabi
5294 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5298 All configurations can now understand and use the DWARF 2 debugging
5299 format. The choice is automatic, if the symbol file contains DWARF 2
5304 GDB now includes basic Java language support. This support is
5305 only useful with Java compilers that produce native machine code.
5307 * solib-absolute-prefix and solib-search-path
5309 For SunOS and SVR4 shared libraries, you may now set the prefix for
5310 loading absolute shared library symbol files, and the search path for
5311 locating non-absolute shared library symbol files.
5313 * Live range splitting
5315 GDB can now effectively debug code for which GCC has performed live
5316 range splitting as part of its optimization. See gdb/doc/LRS for
5317 more details on the expected format of the stabs information.
5321 GDB's support for the GNU Hurd, including thread debugging, has been
5322 updated to work with current versions of the Hurd.
5326 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5327 instruction set. ARM GDB automatically detects when Thumb
5328 instructions are in use, and adjusts disassembly and backtracing
5333 GDB's MIPS target configurations now handle the MIP16 16-bit
5338 GDB now includes support for overlays; if an executable has been
5339 linked such that multiple sections are based at the same address, GDB
5340 will decide which section to use for symbolic info. You can choose to
5341 control the decision manually, using overlay commands, or implement
5342 additional target-side support and use "overlay load-target" to bring
5343 in the overlay mapping. Do "help overlay" for more detail.
5347 The command "info symbol <address>" displays information about
5348 the symbol at the specified address.
5352 The standard remote protocol now includes an extension that allows
5353 asynchronous collection and display of trace data. This requires
5354 extensive support in the target-side debugging stub. Tracing mode
5355 includes a new interaction mode in GDB and new commands: see the
5356 file tracepoint.c for more details.
5360 Configurations for embedded MIPS now include a simulator contributed
5361 by Cygnus Solutions. The simulator supports the instruction sets
5362 of most MIPS variants.
5366 Sparc configurations may now include the ERC32 simulator contributed
5367 by the European Space Agency. The simulator is not built into
5368 Sparc targets by default; configure with --enable-sim to include it.
5372 For target configurations that may include multiple variants of a
5373 basic architecture (such as MIPS and SH), you may now set the
5374 architecture explicitly. "set arch" sets, "info arch" lists
5375 the possible architectures.
5377 *** Changes in GDB-4.16:
5379 * New native configurations
5381 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5382 M68K NetBSD m68k-*-netbsd*
5383 PowerPC AIX 4.x powerpc-*-aix*
5384 PowerPC MacOS powerpc-*-macos*
5385 PowerPC Windows NT powerpcle-*-cygwin32
5386 RS/6000 AIX 4.x rs6000-*-aix4*
5390 ARM with RDP protocol arm-*-*
5391 I960 with MON960 i960-*-coff
5392 MIPS VxWorks mips*-*-vxworks*
5393 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5394 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5396 Matra Sparclet sparclet-*-*
5400 The powerpc-eabi configuration now includes the PSIM simulator,
5401 contributed by Andrew Cagney, with assistance from Mike Meissner.
5402 PSIM is a very elaborate model of the PowerPC, including not only
5403 basic instruction set execution, but also details of execution unit
5404 performance and I/O hardware. See sim/ppc/README for more details.
5408 GDB now works with Solaris 2.5.
5410 * Windows 95/NT native
5412 GDB will now work as a native debugger on Windows 95 and Windows NT.
5413 To build it from source, you must use the "gnu-win32" environment,
5414 which uses a DLL to emulate enough of Unix to run the GNU tools.
5415 Further information, binaries, and sources are available at
5416 ftp.cygnus.com, under pub/gnu-win32.
5418 * dont-repeat command
5420 If a user-defined command includes the command `dont-repeat', then the
5421 command will not be repeated if the user just types return. This is
5422 useful if the command is time-consuming to run, so that accidental
5423 extra keystrokes don't run the same command many times.
5425 * Send break instead of ^C
5427 The standard remote protocol now includes an option to send a break
5428 rather than a ^C to the target in order to interrupt it. By default,
5429 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5431 * Remote protocol timeout
5433 The standard remote protocol includes a new variable `remotetimeout'
5434 that allows you to set the number of seconds before GDB gives up trying
5435 to read from the target. The default value is 2.
5437 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5439 By default GDB will automatically keep track of objects as they are
5440 loaded and unloaded by the dynamic linker. By using the command `set
5441 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5442 when shared library events occur, thus allowing you to set breakpoints
5443 in shared libraries which are explicitly loaded by the inferior.
5445 Note this feature does not work on hpux8. On hpux9 you must link
5446 /usr/lib/end.o into your program. This feature should work
5447 automatically on hpux10.
5449 * Irix 5.x hardware watchpoint support
5451 Irix 5 configurations now support the use of hardware watchpoints.
5453 * Mips protocol "SYN garbage limit"
5455 When debugging a Mips target using the `target mips' protocol, you
5456 may set the number of characters that GDB will ignore by setting
5457 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5458 every character. The default value is 1050.
5460 * Recording and replaying remote debug sessions
5462 If you set `remotelogfile' to the name of a file, gdb will write to it
5463 a recording of a remote debug session. This recording may then be
5464 replayed back to gdb using "gdbreplay". See gdbserver/README for
5465 details. This is useful when you have a problem with GDB while doing
5466 remote debugging; you can make a recording of the session and send it
5467 to someone else, who can then recreate the problem.
5469 * Speedups for remote debugging
5471 GDB includes speedups for downloading and stepping MIPS systems using
5472 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5473 and more efficient S-record downloading.
5475 * Memory use reductions and statistics collection
5477 GDB now uses less memory and reports statistics about memory usage.
5478 Try the `maint print statistics' command, for example.
5480 *** Changes in GDB-4.15:
5482 * Psymtabs for XCOFF
5484 The symbol reader for AIX GDB now uses partial symbol tables. This
5485 can greatly improve startup time, especially for large executables.
5487 * Remote targets use caching
5489 Remote targets now use a data cache to speed up communication with the
5490 remote side. The data cache could lead to incorrect results because
5491 it doesn't know about volatile variables, thus making it impossible to
5492 debug targets which use memory mapped I/O devices. `set remotecache
5493 off' turns the the data cache off.
5495 * Remote targets may have threads
5497 The standard remote protocol now includes support for multiple threads
5498 in the target system, using new protocol commands 'H' and 'T'. See
5499 gdb/remote.c for details.
5503 If GDB is configured with `--enable-netrom', then it will include
5504 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5505 acts as though it is a bank of ROM on the target board, but you can
5506 write into it over the network. GDB's support consists only of
5507 support for fast loading into the emulated ROM; to debug, you must use
5508 another protocol, such as standard remote protocol. The usual
5509 sequence is something like
5511 target nrom <netrom-hostname>
5513 target remote <netrom-hostname>:1235
5517 GDB now includes support for the Apple Macintosh, as a host only. It
5518 may be run as either an MPW tool or as a standalone application, and
5519 it can debug through the serial port. All the usual GDB commands are
5520 available, but to the target command, you must supply "serial" as the
5521 device type instead of "/dev/ttyXX". See mpw-README in the main
5522 directory for more information on how to build. The MPW configuration
5523 scripts */mpw-config.in support only a few targets, and only the
5524 mips-idt-ecoff target has been tested.
5528 GDB configuration now uses autoconf. This is not user-visible,
5529 but does simplify configuration and building.
5533 GDB now supports hpux10.
5535 *** Changes in GDB-4.14:
5537 * New native configurations
5539 x86 FreeBSD i[345]86-*-freebsd
5540 x86 NetBSD i[345]86-*-netbsd
5541 NS32k NetBSD ns32k-*-netbsd
5542 Sparc NetBSD sparc-*-netbsd
5546 A29K VxWorks a29k-*-vxworks
5547 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5548 CPU32 EST-300 emulator m68*-*-est*
5549 PowerPC ELF powerpc-*-elf
5552 * Alpha OSF/1 support for procfs
5554 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5555 possible to attach to running processes. As the mounting of the /proc
5556 filesystem is optional on the Alpha, GDB automatically determines
5557 the availability of /proc during startup. This can lead to problems
5558 if /proc is unmounted after GDB has been started.
5560 * Arguments to user-defined commands
5562 User commands may accept up to 10 arguments separated by whitespace.
5563 Arguments are accessed within the user command via $arg0..$arg9. A
5566 print $arg0 + $arg1 + $arg2
5568 To execute the command use:
5571 Defines the command "adder" which prints the sum of its three arguments.
5572 Note the arguments are text substitutions, so they may reference variables,
5573 use complex expressions, or even perform inferior function calls.
5575 * New `if' and `while' commands
5577 This makes it possible to write more sophisticated user-defined
5578 commands. Both commands take a single argument, which is the
5579 expression to evaluate, and must be followed by the commands to
5580 execute, one per line, if the expression is nonzero, the list being
5581 terminated by the word `end'. The `if' command list may include an
5582 `else' word, which causes the following commands to be executed only
5583 if the expression is zero.
5585 * Fortran source language mode
5587 GDB now includes partial support for Fortran 77. It will recognize
5588 Fortran programs and can evaluate a subset of Fortran expressions, but
5589 variables and functions may not be handled correctly. GDB will work
5590 with G77, but does not yet know much about symbols emitted by other
5593 * Better HPUX support
5595 Most debugging facilities now work on dynamic executables for HPPAs
5596 running hpux9 or later. You can attach to running dynamically linked
5597 processes, but by default the dynamic libraries will be read-only, so
5598 for instance you won't be able to put breakpoints in them. To change
5599 that behavior do the following before running the program:
5605 This will cause the libraries to be mapped private and read-write.
5606 To revert to the normal behavior, do this:
5612 You cannot set breakpoints or examine data in the library until after
5613 the library is loaded if the function/data symbols do not have
5616 GDB can now also read debug symbols produced by the HP C compiler on
5617 HPPAs (sorry, no C++, Fortran or 68k support).
5619 * Target byte order now dynamically selectable
5621 You can choose which byte order to use with a target system, via the
5622 commands "set endian big" and "set endian little", and you can see the
5623 current setting by using "show endian". You can also give the command
5624 "set endian auto", in which case GDB will use the byte order
5625 associated with the executable. Currently, only embedded MIPS
5626 configurations support dynamic selection of target byte order.
5628 * New DOS host serial code
5630 This version uses DPMI interrupts to handle buffered I/O, so you
5631 no longer need to run asynctsr when debugging boards connected to
5634 *** Changes in GDB-4.13:
5636 * New "complete" command
5638 This lists all the possible completions for the rest of the line, if it
5639 were to be given as a command itself. This is intended for use by emacs.
5641 * Trailing space optional in prompt
5643 "set prompt" no longer adds a space for you after the prompt you set. This
5644 allows you to set a prompt which ends in a space or one that does not.
5646 * Breakpoint hit counts
5648 "info break" now displays a count of the number of times the breakpoint
5649 has been hit. This is especially useful in conjunction with "ignore"; you
5650 can ignore a large number of breakpoint hits, look at the breakpoint info
5651 to see how many times the breakpoint was hit, then run again, ignoring one
5652 less than that number, and this will get you quickly to the last hit of
5655 * Ability to stop printing at NULL character
5657 "set print null-stop" will cause GDB to stop printing the characters of
5658 an array when the first NULL is encountered. This is useful when large
5659 arrays actually contain only short strings.
5661 * Shared library breakpoints
5663 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5664 breakpoints in shared libraries before the executable is run.
5666 * Hardware watchpoints
5668 There is a new hardware breakpoint for the watch command for sparclite
5669 targets. See gdb/sparclite/hw_breakpoint.note.
5671 Hardware watchpoints are also now supported under GNU/Linux.
5675 Annotations have been added. These are for use with graphical interfaces,
5676 and are still experimental. Currently only gdba.el uses these.
5678 * Improved Irix 5 support
5680 GDB now works properly with Irix 5.2.
5682 * Improved HPPA support
5684 GDB now works properly with the latest GCC and GAS.
5686 * New native configurations
5688 Sequent PTX4 i[34]86-sequent-ptx4
5689 HPPA running OSF/1 hppa*-*-osf*
5690 Atari TT running SVR4 m68*-*-sysv4*
5691 RS/6000 LynxOS rs6000-*-lynxos*
5695 OS/9000 i[34]86-*-os9k
5696 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5699 * Hitachi SH7000 and E7000-PC ICE support
5701 There is now support for communicating with the Hitachi E7000-PC ICE.
5702 This is available automatically when GDB is configured for the SH.
5706 As usual, a variety of small fixes and improvements, both generic
5707 and configuration-specific. See the ChangeLog for more detail.
5709 *** Changes in GDB-4.12:
5711 * Irix 5 is now supported
5715 GDB-4.12 on the HPPA has a number of changes which make it unable
5716 to debug the output from the currently released versions of GCC and
5717 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5718 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5719 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5722 *** Changes in GDB-4.11:
5724 * User visible changes:
5728 The "set remotedebug" option is now consistent between the mips remote
5729 target, remote targets using the gdb-specific protocol, UDI (AMD's
5730 debug protocol for the 29k) and the 88k bug monitor. It is now an
5731 integer specifying a debug level (normally 0 or 1, but 2 means more
5732 debugging info for the mips target).
5734 * DEC Alpha native support
5736 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5737 debug info, but GDB works fairly well with the DEC compiler and should
5738 work with a future GCC release. See the README file for a few
5739 Alpha-specific notes.
5741 * Preliminary thread implementation
5743 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5745 * LynxOS native and target support for 386
5747 This release has been hosted on LynxOS 2.2, and also can be configured
5748 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5751 * Improvements in C++ mangling/demangling.
5753 This release has much better g++ debugging, specifically in name
5754 mangling/demangling, virtual function calls, print virtual table,
5755 call methods, ...etc.
5757 *** Changes in GDB-4.10:
5759 * User visible changes:
5761 Remote debugging using the GDB-specific (`target remote') protocol now
5762 supports the `load' command. This is only useful if you have some
5763 other way of getting the stub to the target system, and you can put it
5764 somewhere in memory where it won't get clobbered by the download.
5766 Filename completion now works.
5768 When run under emacs mode, the "info line" command now causes the
5769 arrow to point to the line specified. Also, "info line" prints
5770 addresses in symbolic form (as well as hex).
5772 All vxworks based targets now support a user settable option, called
5773 vxworks-timeout. This option represents the number of seconds gdb
5774 should wait for responses to rpc's. You might want to use this if
5775 your vxworks target is, perhaps, a slow software simulator or happens
5776 to be on the far side of a thin network line.
5780 This release contains support for using a DEC alpha as a GDB host for
5781 cross debugging. Native alpha debugging is not supported yet.
5784 *** Changes in GDB-4.9:
5788 This is the first GDB release which is accompanied by a matching testsuite.
5789 The testsuite requires installation of dejagnu, which should be available
5790 via ftp from most sites that carry GNU software.
5794 'Cfront' style demangling has had its name changed to 'ARM' style, to
5795 emphasize that it was written from the specifications in the C++ Annotated
5796 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5797 disclaimers, it still generated too much confusion with users attempting to
5798 use gdb with AT&T cfront.
5802 GDB now uses a standard remote interface to a simulator library.
5803 So far, the library contains simulators for the Zilog Z8001/2, the
5804 Hitachi H8/300, H8/500 and Super-H.
5806 * New targets supported
5808 H8/300 simulator h8300-hitachi-hms or h8300hms
5809 H8/500 simulator h8500-hitachi-hms or h8500hms
5810 SH simulator sh-hitachi-hms or sh
5811 Z8000 simulator z8k-zilog-none or z8ksim
5812 IDT MIPS board over serial line mips-idt-ecoff
5814 Cross-debugging to GO32 targets is supported. It requires a custom
5815 version of the i386-stub.c module which is integrated with the
5816 GO32 memory extender.
5818 * New remote protocols
5820 MIPS remote debugging protocol.
5822 * New source languages supported
5824 This version includes preliminary support for Chill, a Pascal like language
5825 used by telecommunications companies. Chill support is also being integrated
5826 into the GNU compiler, but we don't know when it will be publically available.
5829 *** Changes in GDB-4.8:
5831 * HP Precision Architecture supported
5833 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5834 version of this support was available as a set of patches from the
5835 University of Utah. GDB does not support debugging of programs
5836 compiled with the HP compiler, because HP will not document their file
5837 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5838 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5840 Many problems in the preliminary version have been fixed.
5842 * Faster and better demangling
5844 We have improved template demangling and fixed numerous bugs in the GNU style
5845 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5846 character types (wchar_t) are now supported. Demangling of each symbol is now
5847 only done once, and is cached when the symbol table for a file is read in.
5848 This results in a small increase in memory usage for C programs, a moderate
5849 increase in memory usage for C++ programs, and a fantastic speedup in
5852 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5853 from the specifications in the Annotated Reference Manual, which AT&T's
5854 compiler does not actually implement.
5856 * G++ multiple inheritance compiler problem
5858 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5859 inheritance lattices was reworked to properly discover ambiguities. We
5860 recently found an example which causes this new algorithm to fail in a
5861 very subtle way, producing bad debug information for those classes.
5862 The file 'gcc.patch' (in this directory) can be applied to gcc to
5863 circumvent the problem. A future GCC release will contain a complete
5866 The previous G++ debug info problem (mentioned below for the gdb-4.7
5867 release) is fixed in gcc version 2.3.2.
5869 * Improved configure script
5871 The `configure' script will now attempt to guess your system type if
5872 you don't supply a host system type. The old scheme of supplying a
5873 host system triplet is preferable over using this. All the magic is
5874 done in the new `config.guess' script. Examine it for details.
5876 We have also brought our configure script much more in line with the FSF's
5877 version. It now supports the --with-xxx options. In particular,
5878 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5879 The resulting GDB will not be able to read arbitrary object file formats --
5880 only the format ``expected'' to be used on the configured target system.
5881 We hope to make this the default in a future release.
5883 * Documentation improvements
5885 There's new internal documentation on how to modify GDB, and how to
5886 produce clean changes to the code. We implore people to read it
5887 before submitting changes.
5889 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5890 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5891 `info' files are also provided. To build `info' files from scratch,
5892 you will need the latest `makeinfo' release, which will be available in
5893 a future texinfo-X.Y release.
5895 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5896 We're not sure exactly which versions have this problem, but it has
5897 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5898 or better. If that isn't possible, there is a patch in
5899 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5900 around this problem.
5904 GDB now supports array constants that can be used in expressions typed in by
5905 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5906 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5909 The new directory `gdb/sparclite' contains a program that demonstrates
5910 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5912 * New native hosts supported
5914 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5915 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5917 * New targets supported
5919 AMD 29k family via UDI a29k-amd-udi or udi29k
5921 * New file formats supported
5923 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5924 HPUX core files, and SCO 3.2v2 core files.
5928 Attaching to processes now works again; thanks for the many bug reports.
5930 We have also stomped on a bunch of core dumps caused by
5931 printf_filtered("%s") problems.
5933 We eliminated a copyright problem on the rpc and ptrace header files
5934 for VxWorks, which was discovered at the last minute during the 4.7
5935 release. You should now be able to build a VxWorks GDB.
5937 You can now interrupt gdb while an attached process is running. This
5938 will cause the attached process to stop, and give control back to GDB.
5940 We fixed problems caused by using too many file descriptors
5941 for reading symbols from object files and libraries. This was
5942 especially a problem for programs that used many (~100) shared
5945 The `step' command now only enters a subroutine if there is line number
5946 information for the subroutine. Otherwise it acts like the `next'
5947 command. Previously, `step' would enter subroutines if there was
5948 any debugging information about the routine. This avoids problems
5949 when using `cc -g1' on MIPS machines.
5951 * Internal improvements
5953 GDB's internal interfaces have been improved to make it easier to support
5954 debugging of multiple languages in the future.
5956 GDB now uses a common structure for symbol information internally.
5957 Minimal symbols (derived from linkage symbols in object files), partial
5958 symbols (from a quick scan of debug information), and full symbols
5959 contain a common subset of information, making it easier to write
5960 shared code that handles any of them.
5962 * New command line options
5964 We now accept --silent as an alias for --quiet.
5968 The memory-mapped-malloc library is now licensed under the GNU Library
5969 General Public License.
5971 *** Changes in GDB-4.7:
5973 * Host/native/target split
5975 GDB has had some major internal surgery to untangle the support for
5976 hosts and remote targets. Now, when you configure GDB for a remote
5977 target, it will no longer load in all of the support for debugging
5978 local programs on the host. When fully completed and tested, this will
5979 ensure that arbitrary host/target combinations are possible.
5981 The primary conceptual shift is to separate the non-portable code in
5982 GDB into three categories. Host specific code is required any time GDB
5983 is compiled on that host, regardless of the target. Target specific
5984 code relates to the peculiarities of the target, but can be compiled on
5985 any host. Native specific code is everything else: it can only be
5986 built when the host and target are the same system. Child process
5987 handling and core file support are two common `native' examples.
5989 GDB's use of /proc for controlling Unix child processes is now cleaner.
5990 It has been split out into a single module under the `target_ops' vector,
5991 plus two native-dependent functions for each system that uses /proc.
5993 * New hosts supported
5995 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5996 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5997 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5999 * New targets supported
6001 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6002 68030 and CPU32 m68030-*-*, m68332-*-*
6004 * New native hosts supported
6006 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6007 (386bsd is not well tested yet)
6008 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6010 * New file formats supported
6012 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6013 supports reading of `a.out.adobe' object files, which are an a.out
6014 format extended with minimal information about multiple sections.
6018 `show copying' is the same as the old `info copying'.
6019 `show warranty' is the same as `info warrantee'.
6020 These were renamed for consistency. The old commands continue to work.
6022 `info handle' is a new alias for `info signals'.
6024 You can now define pre-command hooks, which attach arbitrary command
6025 scripts to any command. The commands in the hook will be executed
6026 prior to the user's command. You can also create a hook which will be
6027 executed whenever the program stops. See gdb.texinfo.
6031 We now deal with Cfront style name mangling, and can even extract type
6032 info from mangled symbols. GDB can automatically figure out which
6033 symbol mangling style your C++ compiler uses.
6035 Calling of methods and virtual functions has been improved as well.
6039 The crash that occured when debugging Sun Ansi-C compiled binaries is
6040 fixed. This was due to mishandling of the extra N_SO stabs output
6043 We also finally got Ultrix 4.2 running in house, and fixed core file
6044 support, with help from a dozen people on the net.
6046 John M. Farrell discovered that the reason that single-stepping was so
6047 slow on all of the Mips based platforms (primarily SGI and DEC) was
6048 that we were trying to demangle and lookup a symbol used for internal
6049 purposes on every instruction that was being stepped through. Changing
6050 the name of that symbol so that it couldn't be mistaken for a C++
6051 mangled symbol sped things up a great deal.
6053 Rich Pixley sped up symbol lookups in general by getting much smarter
6054 about when C++ symbol mangling is necessary. This should make symbol
6055 completion (TAB on the command line) much faster. It's not as fast as
6056 we'd like, but it's significantly faster than gdb-4.6.
6060 A new user controllable variable 'call_scratch_address' can
6061 specify the location of a scratch area to be used when GDB
6062 calls a function in the target. This is necessary because the
6063 usual method of putting the scratch area on the stack does not work
6064 in systems that have separate instruction and data spaces.
6066 We integrated changes to support the 29k UDI (Universal Debugger
6067 Interface), but discovered at the last minute that we didn't have all
6068 of the appropriate copyright paperwork. We are working with AMD to
6069 resolve this, and hope to have it available soon.
6073 We have sped up the remote serial line protocol, especially for targets
6074 with lots of registers. It now supports a new `expedited status' ('T')
6075 message which can be used in place of the existing 'S' status message.
6076 This allows the remote stub to send only the registers that GDB
6077 needs to make a quick decision about single-stepping or conditional
6078 breakpoints, eliminating the need to fetch the entire register set for
6079 each instruction being stepped through.
6081 The GDB remote serial protocol now implements a write-through cache for
6082 registers, only re-reading the registers if the target has run.
6084 There is also a new remote serial stub for SPARC processors. You can
6085 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6086 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6087 processor with a serial port.
6091 Configure.in files have become much easier to read and modify. A new
6092 `table driven' format makes it more obvious what configurations are
6093 supported, and what files each one uses.
6097 There is a new opcodes library which will eventually contain all of the
6098 disassembly routines and opcode tables. At present, it only contains
6099 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6100 disassembler (binutils/objdump) to share these routines.
6102 The libiberty library is now copylefted under the GNU Library General
6103 Public License. This allows more liberal use, and was done so libg++
6104 can use it. This makes no difference to GDB, since the Library License
6105 grants all the rights from the General Public License.
6109 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6110 reference to the stabs symbol info used by the debugger. It is (as far
6111 as we know) the only published document on this fascinating topic. We
6112 encourage you to read it, compare it to the stabs information on your
6113 system, and send improvements on the document in general (to
6114 bug-gdb@prep.ai.mit.edu).
6116 And, of course, many bugs have been fixed.
6119 *** Changes in GDB-4.6:
6121 * Better support for C++ function names
6123 GDB now accepts as input the "demangled form" of C++ overloaded function
6124 names and member function names, and can do command completion on such names
6125 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6126 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6127 Make use of command completion, it is your friend.
6129 GDB also now accepts a variety of C++ mangled symbol formats. They are
6130 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6131 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6132 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6133 for the list of formats.
6135 * G++ symbol mangling problem
6137 Recent versions of gcc have a bug in how they emit debugging information for
6138 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6139 directory) can be applied to gcc to fix the problem. Alternatively, if you
6140 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6141 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6142 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6145 * New 'maintenance' command
6147 All of the commands related to hacking GDB internals have been moved out of
6148 the main command set, and now live behind the 'maintenance' command. This
6149 can also be abbreviated as 'mt'. The following changes were made:
6151 dump-me -> maintenance dump-me
6152 info all-breakpoints -> maintenance info breakpoints
6153 printmsyms -> maintenance print msyms
6154 printobjfiles -> maintenance print objfiles
6155 printpsyms -> maintenance print psymbols
6156 printsyms -> maintenance print symbols
6158 The following commands are new:
6160 maintenance demangle Call internal GDB demangler routine to
6161 demangle a C++ link name and prints the result.
6162 maintenance print type Print a type chain for a given symbol
6164 * Change to .gdbinit file processing
6166 We now read the $HOME/.gdbinit file before processing the argv arguments
6167 (e.g. reading symbol files or core files). This allows global parameters to
6168 be set, which will apply during the symbol reading. The ./.gdbinit is still
6169 read after argv processing.
6171 * New hosts supported
6173 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6175 GNU/Linux support i386-unknown-linux or linux
6177 We are also including code to support the HP/PA running BSD and HPUX. This
6178 is almost guaranteed not to work, as we didn't have time to test or build it
6179 for this release. We are including it so that the more adventurous (or
6180 masochistic) of you can play with it. We also had major problems with the
6181 fact that the compiler that we got from HP doesn't support the -g option.
6184 * New targets supported
6186 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6188 * More smarts about finding #include files
6190 GDB now remembers the compilation directory for all include files, and for
6191 all files from which C is generated (like yacc and lex sources). This
6192 greatly improves GDB's ability to find yacc/lex sources, and include files,
6193 especially if you are debugging your program from a directory different from
6194 the one that contains your sources.
6196 We also fixed a bug which caused difficulty with listing and setting
6197 breakpoints in include files which contain C code. (In the past, you had to
6198 try twice in order to list an include file that you hadn't looked at before.)
6200 * Interesting infernals change
6202 GDB now deals with arbitrary numbers of sections, where the symbols for each
6203 section must be relocated relative to that section's landing place in the
6204 target's address space. This work was needed to support ELF with embedded
6205 stabs used by Solaris-2.0.
6207 * Bug fixes (of course!)
6209 There have been loads of fixes for the following things:
6210 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6211 i960, stabs, DOS(GO32), procfs, etc...
6213 See the ChangeLog for details.
6215 *** Changes in GDB-4.5:
6217 * New machines supported (host and target)
6219 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6221 SGI Irix-4.x mips-sgi-irix4 or iris4
6223 * New malloc package
6225 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6226 Mmalloc is capable of handling mutiple heaps of memory. It is also
6227 capable of saving a heap to a file, and then mapping it back in later.
6228 This can be used to greatly speedup the startup of GDB by using a
6229 pre-parsed symbol table which lives in a mmalloc managed heap. For
6230 more details, please read mmalloc/mmalloc.texi.
6234 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6235 'help info proc' for details.
6237 * MIPS ecoff symbol table format
6239 The code that reads MIPS symbol table format is now supported on all hosts.
6240 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6243 * File name changes for MS-DOS
6245 Many files in the config directories have been renamed to make it easier to
6246 support GDB on MS-DOSe systems (which have very restrictive file name
6247 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6248 environment) is close to working but has some remaining problems. Note
6249 that debugging of DOS programs is not supported, due to limitations
6250 in the ``operating system'', but it can be used to host cross-debugging.
6252 * Cross byte order fixes
6254 Many fixes have been made to support cross debugging of Sparc and MIPS
6255 targets from hosts whose byte order differs.
6257 * New -mapped and -readnow options
6259 If memory-mapped files are available on your system through the 'mmap'
6260 system call, you can use the -mapped option on the `file' or
6261 `symbol-file' commands to cause GDB to write the symbols from your
6262 program into a reusable file. If the program you are debugging is
6263 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6264 Future GDB debugging sessions will notice the presence of this file,
6265 and will quickly map in symbol information from it, rather than reading
6266 the symbol table from the executable program. Using the '-mapped'
6267 option in a GDB `file' or `symbol-file' command has the same effect as
6268 starting GDB with the '-mapped' command-line option.
6270 You can cause GDB to read the entire symbol table immediately by using
6271 the '-readnow' option with any of the commands that load symbol table
6272 information (or on the GDB command line). This makes the command
6273 slower, but makes future operations faster.
6275 The -mapped and -readnow options are typically combined in order to
6276 build a `fred.syms' file that contains complete symbol information.
6277 A simple GDB invocation to do nothing but build a `.syms' file for future
6280 gdb -batch -nx -mapped -readnow programname
6282 The `.syms' file is specific to the host machine on which GDB is run.
6283 It holds an exact image of GDB's internal symbol table. It cannot be
6284 shared across multiple host platforms.
6286 * longjmp() handling
6288 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6289 siglongjmp() without losing control. This feature has not yet been ported to
6290 all systems. It currently works on many 386 platforms, all MIPS-based
6291 platforms (SGI, DECstation, etc), and Sun3/4.
6295 Preliminary work has been put in to support the new Solaris OS from Sun. At
6296 this time, it can control and debug processes, but it is not capable of
6301 As always, many many bug fixes. The major areas were with g++, and mipsread.
6302 People using the MIPS-based platforms should experience fewer mysterious
6303 crashes and trashed symbol tables.
6305 *** Changes in GDB-4.4:
6307 * New machines supported (host and target)
6309 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6311 BSD Reno on Vax vax-dec-bsd
6312 Ultrix on Vax vax-dec-ultrix
6314 * New machines supported (target)
6316 AMD 29000 embedded, using EBMON a29k-none-none
6320 GDB continues to improve its handling of C++. `References' work better.
6321 The demangler has also been improved, and now deals with symbols mangled as
6322 per the Annotated C++ Reference Guide.
6324 GDB also now handles `stabs' symbol information embedded in MIPS
6325 `ecoff' symbol tables. Since the ecoff format was not easily
6326 extensible to handle new languages such as C++, this appeared to be a
6327 good way to put C++ debugging info into MIPS binaries. This option
6328 will be supported in the GNU C compiler, version 2, when it is
6331 * New features for SVR4
6333 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6334 shared libraries. Debugging dynamically linked programs should present
6335 only minor differences from debugging statically linked programs.
6337 The `info proc' command will print out information about any process
6338 on an SVR4 system (including the one you are debugging). At the moment,
6339 it prints the address mappings of the process.
6341 If you bring up GDB on another SVR4 system, please send mail to
6342 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6344 * Better dynamic linking support in SunOS
6346 Reading symbols from shared libraries which contain debugging symbols
6347 now works properly. However, there remain issues such as automatic
6348 skipping of `transfer vector' code during function calls, which
6349 make it harder to debug code in a shared library, than to debug the
6350 same code linked statically.
6354 GDB is now using the latest `getopt' routines from the FSF. This
6355 version accepts the -- prefix for options with long names. GDB will
6356 continue to accept the old forms (-option and +option) as well.
6357 Various single letter abbreviations for options have been explicity
6358 added to the option table so that they won't get overshadowed in the
6359 future by other options that begin with the same letter.
6363 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6364 Many assorted bugs have been handled. Many more remain to be handled.
6365 See the various ChangeLog files (primarily in gdb and bfd) for details.
6368 *** Changes in GDB-4.3:
6370 * New machines supported (host and target)
6372 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6373 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6374 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6376 * Almost SCO Unix support
6378 We had hoped to support:
6379 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6380 (except for core file support), but we discovered very late in the release
6381 that it has problems with process groups that render gdb unusable. Sorry
6382 about that. I encourage people to fix it and post the fixes.
6384 * Preliminary ELF and DWARF support
6386 GDB can read ELF object files on System V Release 4, and can handle
6387 debugging records for C, in DWARF format, in ELF files. This support
6388 is preliminary. If you bring up GDB on another SVR4 system, please
6389 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6394 GDB now uses the latest `readline' library. One user-visible change
6395 is that two tabs will list possible command completions, which previously
6396 required typing M-? (meta-question mark, or ESC ?).
6400 The `stepi' bug that many of you noticed has been squashed.
6401 Many bugs in C++ have been handled. Many more remain to be handled.
6402 See the various ChangeLog files (primarily in gdb and bfd) for details.
6404 * State of the MIPS world (in case you wondered):
6406 GDB can understand the symbol tables emitted by the compilers
6407 supplied by most vendors of MIPS-based machines, including DEC. These
6408 symbol tables are in a format that essentially nobody else uses.
6410 Some versions of gcc come with an assembler post-processor called
6411 mips-tfile. This program is required if you want to do source-level
6412 debugging of gcc-compiled programs. I believe FSF does not ship
6413 mips-tfile with gcc version 1, but it will eventually come with gcc
6416 Debugging of g++ output remains a problem. g++ version 1.xx does not
6417 really support it at all. (If you're lucky, you should be able to get
6418 line numbers and stack traces to work, but no parameters or local
6419 variables.) With some work it should be possible to improve the
6422 When gcc version 2 is released, you will have somewhat better luck.
6423 However, even then you will get confusing results for inheritance and
6426 We will eventually provide full debugging of g++ output on
6427 DECstations. This will probably involve some kind of stabs-in-ecoff
6428 encapulation, but the details have not been worked out yet.
6431 *** Changes in GDB-4.2:
6433 * Improved configuration
6435 Only one copy of `configure' exists now, and it is not self-modifying.
6436 Porting BFD is simpler.
6440 The `step' and `next' commands now only stop at the first instruction
6441 of a source line. This prevents the multiple stops that used to occur
6442 in switch statements, for-loops, etc. `Step' continues to stop if a
6443 function that has debugging information is called within the line.
6447 Lots of small bugs fixed. More remain.
6449 * New host supported (not target)
6451 Intel 386 PC clone running Mach i386-none-mach
6454 *** Changes in GDB-4.1:
6456 * Multiple source language support
6458 GDB now has internal scaffolding to handle several source languages.
6459 It determines the type of each source file from its filename extension,
6460 and will switch expression parsing and number formatting to match the
6461 language of the function in the currently selected stack frame.
6462 You can also specifically set the language to be used, with
6463 `set language c' or `set language modula-2'.
6467 GDB now has preliminary support for the GNU Modula-2 compiler,
6468 currently under development at the State University of New York at
6469 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6470 continue through the fall of 1991 and into 1992.
6472 Other Modula-2 compilers are currently not supported, and attempting to
6473 debug programs compiled with them will likely result in an error as the
6474 symbol table is read. Feel free to work on it, though!
6476 There are hooks in GDB for strict type checking and range checking,
6477 in the `Modula-2 philosophy', but they do not currently work.
6481 GDB can now write to executable and core files (e.g. patch
6482 a variable's value). You must turn this switch on, specify
6483 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6484 by assigning a new value to a variable. Modifications take
6487 * Automatic SunOS shared library reading
6489 When you run your program, GDB automatically determines where its
6490 shared libraries (if any) have been loaded, and reads their symbols.
6491 The `share' command is no longer needed. This also works when
6492 examining core files.
6496 You can specify the number of lines that the `list' command shows.
6499 * New machines supported (host and target)
6501 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6502 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6503 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6505 * New hosts supported (not targets)
6507 IBM RT/PC: romp-ibm-aix or rtpc
6509 * New targets supported (not hosts)
6511 AMD 29000 embedded with COFF a29k-none-coff
6512 AMD 29000 embedded with a.out a29k-none-aout
6513 Ultracomputer remote kernel debug a29k-nyu-kern
6515 * New remote interfaces
6521 *** Changes in GDB-4.0:
6525 Wide output is wrapped at good places to make the output more readable.
6527 Gdb now supports cross-debugging from a host machine of one type to a
6528 target machine of another type. Communication with the target system
6529 is over serial lines. The ``target'' command handles connecting to the
6530 remote system; the ``load'' command will download a program into the
6531 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6532 also supports debugging of realtime processes running under VxWorks,
6533 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6534 stub on the target system.
6536 New CPUs supported include the AMD 29000 and Intel 960.
6538 GDB now reads object files and symbol tables via a ``binary file''
6539 library, which allows a single copy of GDB to debug programs of multiple
6540 object file types such as a.out and coff.
6542 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6543 refcard.dvi and refcard.ps are available to format it).
6546 * Control-Variable user interface simplified
6548 All variables that control the operation of the debugger can be set
6549 by the ``set'' command, and displayed by the ``show'' command.
6551 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6552 ``Show prompt'' produces the response:
6553 Gdb's prompt is new-gdb=>.
6555 What follows are the NEW set commands. The command ``help set'' will
6556 print a complete list of old and new set commands. ``help set FOO''
6557 will give a longer description of the variable FOO. ``show'' will show
6558 all of the variable descriptions and their current settings.
6560 confirm on/off: Enables warning questions for operations that are
6561 hard to recover from, e.g. rerunning the program while
6562 it is already running. Default is ON.
6564 editing on/off: Enables EMACS style command line editing
6565 of input. Previous lines can be recalled with
6566 control-P, the current line can be edited with control-B,
6567 you can search for commands with control-R, etc.
6570 history filename NAME: NAME is where the gdb command history
6571 will be stored. The default is .gdb_history,
6572 or the value of the environment variable
6575 history size N: The size, in commands, of the command history. The
6576 default is 256, or the value of the environment variable
6579 history save on/off: If this value is set to ON, the history file will
6580 be saved after exiting gdb. If set to OFF, the
6581 file will not be saved. The default is OFF.
6583 history expansion on/off: If this value is set to ON, then csh-like
6584 history expansion will be performed on
6585 command line input. The default is OFF.
6587 radix N: Sets the default radix for input and output. It can be set
6588 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6589 in the current radix, so "set radix 10" is always a no-op.
6591 height N: This integer value is the number of lines on a page. Default
6592 is 24, the current `stty rows'' setting, or the ``li#''
6593 setting from the termcap entry matching the environment
6596 width N: This integer value is the number of characters on a line.
6597 Default is 80, the current `stty cols'' setting, or the ``co#''
6598 setting from the termcap entry matching the environment
6601 Note: ``set screensize'' is obsolete. Use ``set height'' and
6602 ``set width'' instead.
6604 print address on/off: Print memory addresses in various command displays,
6605 such as stack traces and structure values. Gdb looks
6606 more ``symbolic'' if you turn this off; it looks more
6607 ``machine level'' with it on. Default is ON.
6609 print array on/off: Prettyprint arrays. New convenient format! Default
6612 print demangle on/off: Print C++ symbols in "source" form if on,
6615 print asm-demangle on/off: Same, for assembler level printouts
6618 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6621 * Support for Epoch Environment.
6623 The epoch environment is a version of Emacs v18 with windowing. One
6624 new command, ``inspect'', is identical to ``print'', except that if you
6625 are running in the epoch environment, the value is printed in its own
6629 * Support for Shared Libraries
6631 GDB can now debug programs and core files that use SunOS shared libraries.
6632 Symbols from a shared library cannot be referenced
6633 before the shared library has been linked with the program (this
6634 happens after you type ``run'' and before the function main() is entered).
6635 At any time after this linking (including when examining core files
6636 from dynamically linked programs), gdb reads the symbols from each
6637 shared library when you type the ``sharedlibrary'' command.
6638 It can be abbreviated ``share''.
6640 sharedlibrary REGEXP: Load shared object library symbols for files
6641 matching a unix regular expression. No argument
6642 indicates to load symbols for all shared libraries.
6644 info sharedlibrary: Status of loaded shared libraries.
6649 A watchpoint stops execution of a program whenever the value of an
6650 expression changes. Checking for this slows down execution
6651 tremendously whenever you are in the scope of the expression, but is
6652 quite useful for catching tough ``bit-spreader'' or pointer misuse
6653 problems. Some machines such as the 386 have hardware for doing this
6654 more quickly, and future versions of gdb will use this hardware.
6656 watch EXP: Set a watchpoint (breakpoint) for an expression.
6658 info watchpoints: Information about your watchpoints.
6660 delete N: Deletes watchpoint number N (same as breakpoints).
6661 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6662 enable N: Re-enables watchpoint number N (same as breakpoints).
6665 * C++ multiple inheritance
6667 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6670 * C++ exception handling
6672 Gdb now supports limited C++ exception handling. Besides the existing
6673 ability to breakpoint on an exception handler, gdb can breakpoint on
6674 the raising of an exception (before the stack is peeled back to the
6677 catch FOO: If there is a FOO exception handler in the dynamic scope,
6678 set a breakpoint to catch exceptions which may be raised there.
6679 Multiple exceptions (``catch foo bar baz'') may be caught.
6681 info catch: Lists all exceptions which may be caught in the
6682 current stack frame.
6685 * Minor command changes
6687 The command ``call func (arg, arg, ...)'' now acts like the print
6688 command, except it does not print or save a value if the function's result
6689 is void. This is similar to dbx usage.
6691 The ``up'' and ``down'' commands now always print the frame they end up
6692 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6693 frames without printing.
6695 * New directory command
6697 'dir' now adds directories to the FRONT of the source search path.
6698 The path starts off empty. Source files that contain debug information
6699 about the directory in which they were compiled can be found even
6700 with an empty path; Sun CC and GCC include this information. If GDB can't
6701 find your source file in the current directory, type "dir .".
6703 * Configuring GDB for compilation
6705 For normal use, type ``./configure host''. See README or gdb.texinfo
6708 GDB now handles cross debugging. If you are remotely debugging between
6709 two different machines, type ``./configure host -target=targ''.
6710 Host is the machine where GDB will run; targ is the machine
6711 where the program that you are debugging will run.
projects / deliverable / binutils-gdb.git / blob