1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.8
6 * GDB now supports hardware watchpoints on x86 GNU Hurd.
10 ** You can now access frame registers from Python scripts.
11 ** New attribute 'producer' for gdb.Symtab objects.
12 ** gdb.Objfile objects have a new attribute "progspace",
13 which is the gdb.Progspace object of the containing program space.
14 ** A new event "gdb.clear_objfiles" has been added, triggered when
15 selecting a new file to debug.
17 * New Python-based convenience functions:
19 ** $_caller_is(name [, number_of_frames])
20 ** $_caller_matches(regexp [, number_of_frames])
21 ** $_any_caller_is(name [, number_of_frames])
22 ** $_any_caller_matches(regexp [, number_of_frames])
26 queue-signal signal-name-or-number
27 Queue a signal to be delivered to the thread when it is resumed.
29 * On resume, GDB now always passes the signal the program had stopped
30 for to the thread the signal was sent to, even if the user changed
31 threads before resuming. Previously GDB would often (but not
32 always) deliver the signal to the thread that happens to be current
35 * Conversely, the "signal" command now consistently delivers the
36 requested signal to the current thread. GDB now asks for
37 confirmation if the program had stopped for a signal and the user
38 switched threads meanwhile.
40 * "breakpoint always-inserted" modes "off" and "auto" merged.
42 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
43 won't remove breakpoints from the target until all threads stop,
44 even in non-stop mode. The "auto" mode has been removed, and "off"
45 is now the default mode.
49 ** The -list-thread-groups command outputs an exit-code field for
50 inferiors that have exited.
54 Support for these obsolete configurations has been removed.
60 *** Changes in GDB 7.8
62 * New command line options
65 This is an alias for the --data-directory option.
67 * GDB supports printing and modifying of variable length automatic arrays
68 as specified in ISO C99.
70 * The ARM simulator now supports instruction level tracing
71 with or without disassembly.
75 GDB now has support for scripting using Guile. Whether this is
76 available is determined at configure time.
77 Guile version 2.0 or greater is required.
78 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
80 * New commands (for set/show, see "New options" below)
84 Invoke CODE by passing it to the Guile interpreter.
88 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
90 info auto-load guile-scripts [regexp]
91 Print the list of automatically loaded Guile scripts.
93 * The source command is now capable of sourcing Guile scripts.
94 This feature is dependent on the debugger being built with Guile support.
98 set print symbol-loading (off|brief|full)
99 show print symbol-loading
100 Control whether to print informational messages when loading symbol
101 information for a file. The default is "full", but when debugging
102 programs with large numbers of shared libraries the amount of output
105 set guile print-stack (none|message|full)
106 show guile print-stack
107 Show a stack trace when an error is encountered in a Guile script.
109 set auto-load guile-scripts (on|off)
110 show auto-load guile-scripts
111 Control auto-loading of Guile script files.
113 maint ada set ignore-descriptive-types (on|off)
114 maint ada show ignore-descriptive-types
115 Control whether the debugger should ignore descriptive types in Ada
116 programs. The default is not to ignore the descriptive types. See
117 the user manual for more details on descriptive types and the intended
118 usage of this option.
120 set auto-connect-native-target
122 Control whether GDB is allowed to automatically connect to the
123 native target for the run, attach, etc. commands when not connected
124 to any target yet. See also "target native" below.
126 set record btrace replay-memory-access (read-only|read-write)
127 show record btrace replay-memory-access
128 Control what memory accesses are allowed during replay.
130 maint set target-async (on|off)
131 maint show target-async
132 This controls whether GDB targets operate in syncronous or
133 asyncronous mode. Normally the default is asyncronous, if it is
134 available; but this can be changed to more easily debug problems
135 occurring only in syncronous mode.
137 set mi-async (on|off)
139 Control whether MI asynchronous mode is preferred. This supersedes
140 "set target-async" of previous GDB versions.
142 * "set target-async" is deprecated as a CLI option and is now an alias
143 for "set mi-async" (only puts MI into async mode).
145 * Background execution commands (e.g., "c&", "s&", etc.) are now
146 possible ``out of the box'' if the target supports them. Previously
147 the user would need to explicitly enable the possibility with the
148 "set target-async on" command.
150 * New features in the GDB remote stub, GDBserver
152 ** New option --debug-format=option1[,option2,...] allows one to add
153 additional text to each output. At present only timestamps
154 are supported: --debug-format=timestamps.
155 Timestamps can also be turned on with the
156 "monitor set debug-format timestamps" command from GDB.
158 * The 'record instruction-history' command now starts counting instructions
159 at one. This also affects the instruction ranges reported by the
160 'record function-call-history' command when given the /i modifier.
162 * The command 'record function-call-history' supports a new modifier '/c' to
163 indent the function names based on their call stack depth.
164 The fields for the '/i' and '/l' modifier have been reordered.
165 The source line range is now prefixed with 'at'.
166 The instruction range is now prefixed with 'inst'.
167 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
168 "record instruction-history" and "list" commands.
170 * The ranges given as arguments to the 'record function-call-history' and
171 'record instruction-history' commands are now inclusive.
173 * The btrace record target now supports the 'record goto' command.
174 For locations inside the execution trace, the back trace is computed
175 based on the information stored in the execution trace.
177 * The btrace record target supports limited reverse execution and replay.
178 The target does not record data and therefore does not allow reading
181 * The "catch syscall" command now works on s390*-linux* targets.
183 * The "compare-sections" command is no longer specific to target
184 remote. It now works with all targets.
186 * All native targets are now consistently called "native".
187 Consequently, the "target child", "target GNU", "target djgpp",
188 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
189 commands have been replaced with "target native". The QNX/NTO port
190 leaves the "procfs" target in place and adds a "native" target for
191 consistency with other ports. The impact on users should be minimal
192 as these commands previously either throwed an error, or were
193 no-ops. The target's name is visible in the output of the following
194 commands: "help target", "info target", "info files", "maint print
197 * The "target native" command now connects to the native target. This
198 can be used to launch native programs even when "set
199 auto-connect-native-target" is set to off.
201 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
203 * Support for Intel(R) AVX-512 registers on GNU/Linux.
204 Support displaying and modifying Intel(R) AVX-512 registers
205 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
209 qXfer:btrace:read's annex
210 The qXfer:btrace:read packet supports a new annex 'delta' to read
211 branch trace incrementally.
215 ** Valid Python operations on gdb.Value objects representing
216 structs/classes invoke the corresponding overloaded operators if
218 ** New `Xmethods' feature in the Python API. Xmethods are
219 additional methods or replacements for existing methods of a C++
220 class. This feature is useful for those cases where a method
221 defined in C++ source code could be inlined or optimized out by
222 the compiler, making it unavailable to GDB.
225 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
227 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
228 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
229 its alias "share", instead.
231 * The commands "set remotebaud" and "show remotebaud" are no longer
232 supported. Use "set serial baud" and "show serial baud" (respectively)
237 ** A new option "-gdb-set mi-async" replaces "-gdb-set
238 target-async". The latter is left as a deprecated alias of the
239 former for backward compatibility. If the target supports it,
240 CLI background execution commands are now always possible by
241 default, independently of whether the frontend stated a
242 preference for asynchronous execution with "-gdb-set mi-async".
243 Previously "-gdb-set target-async off" affected both MI execution
244 commands and CLI execution commands.
246 *** Changes in GDB 7.7
248 * Improved support for process record-replay and reverse debugging on
249 arm*-linux* targets. Support for thumb32 and syscall instruction
250 recording has been added.
252 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
254 * GDB now supports Fission DWP file format version 2.
255 http://gcc.gnu.org/wiki/DebugFission
257 * New convenience function "$_isvoid", to check whether an expression
258 is void. A void expression is an expression where the type of the
259 result is "void". For example, some convenience variables may be
260 "void" when evaluated (e.g., "$_exitcode" before the execution of
261 the program being debugged; or an undefined convenience variable).
262 Another example, when calling a function whose return type is
265 * The "maintenance print objfiles" command now takes an optional regexp.
267 * The "catch syscall" command now works on arm*-linux* targets.
269 * GDB now consistently shows "<not saved>" when printing values of
270 registers the debug info indicates have not been saved in the frame
271 and there's nowhere to retrieve them from
272 (callee-saved/call-clobbered registers):
277 (gdb) info registers rax
280 Before, the former would print "<optimized out>", and the latter
281 "*value not available*".
283 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
288 ** Frame filters and frame decorators have been added.
289 ** Temporary breakpoints are now supported.
290 ** Line tables representation has been added.
291 ** New attribute 'parent_type' for gdb.Field objects.
292 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
293 ** New attribute 'name' for gdb.Type objects.
297 Nios II ELF nios2*-*-elf
298 Nios II GNU/Linux nios2*-*-linux
299 Texas Instruments MSP430 msp430*-*-elf
301 * Removed native configurations
303 Support for these a.out NetBSD and OpenBSD obsolete configurations has
304 been removed. ELF variants of these configurations are kept supported.
306 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
307 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
308 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
309 i[34567]86-*-openbsd3.[0-3]
310 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
311 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
312 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
316 Like "catch throw", but catches a re-thrown exception.
318 Renamed from old "maint check-symtabs".
320 Perform consistency checks on symtabs.
322 Expand symtabs matching an optional regexp.
325 Display the details of GDB configure-time options.
327 maint set|show per-command
328 maint set|show per-command space
329 maint set|show per-command time
330 maint set|show per-command symtab
331 Enable display of per-command gdb resource usage.
333 remove-symbol-file FILENAME
334 remove-symbol-file -a ADDRESS
335 Remove a symbol file added via add-symbol-file. The file to remove
336 can be identified by its filename or by an address that lies within
337 the boundaries of this symbol file in memory.
340 info exceptions REGEXP
341 Display the list of Ada exceptions defined in the program being
342 debugged. If provided, only the exceptions whose names match REGEXP
347 set debug symfile off|on
349 Control display of debugging info regarding reading symbol files and
350 symbol tables within those files
352 set print raw frame-arguments
353 show print raw frame-arguments
354 Set/show whether to print frame arguments in raw mode,
355 disregarding any defined pretty-printers.
357 set remote trace-status-packet
358 show remote trace-status-packet
359 Set/show the use of remote protocol qTStatus packet.
363 Control display of debugging messages related to Nios II targets.
367 Control whether target-assisted range stepping is enabled.
369 set startup-with-shell
370 show startup-with-shell
371 Specifies whether Unix child processes are started via a shell or
376 Use the target memory cache for accesses to the code segment. This
377 improves performance of remote debugging (particularly disassembly).
379 * You can now use a literal value 'unlimited' for options that
380 interpret 0 or -1 as meaning "unlimited". E.g., "set
381 trace-buffer-size unlimited" is now an alias for "set
382 trace-buffer-size -1" and "set height unlimited" is now an alias for
385 * The "set debug symtab-create" debugging option of GDB has been changed to
386 accept a verbosity level. 0 means "off", 1 provides basic debugging
387 output, and values of 2 or greater provides more verbose output.
389 * New command-line options
391 Display the details of GDB configure-time options.
393 * The command 'tsave' can now support new option '-ctf' to save trace
394 buffer in Common Trace Format.
396 * Newly installed $prefix/bin/gcore acts as a shell interface for the
399 * GDB now implements the the C++ 'typeid' operator.
401 * The new convenience variable $_exception holds the exception being
402 thrown or caught at an exception-related catchpoint.
404 * The exception-related catchpoints, like "catch throw", now accept a
405 regular expression which can be used to filter exceptions by type.
407 * The new convenience variable $_exitsignal is automatically set to
408 the terminating signal number when the program being debugged dies
409 due to an uncaught signal.
413 ** All MI commands now accept an optional "--language" option.
414 Support for this feature can be verified by using the "-list-features"
415 command, which should contain "language-option".
417 ** The new command -info-gdb-mi-command allows the user to determine
418 whether a GDB/MI command is supported or not.
420 ** The "^error" result record returned when trying to execute an undefined
421 GDB/MI command now provides a variable named "code" whose content is the
422 "undefined-command" error code. Support for this feature can be verified
423 by using the "-list-features" command, which should contain
424 "undefined-command-error-code".
426 ** The -trace-save MI command can optionally save trace buffer in Common
429 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
431 ** The command -data-list-register-values now accepts an optional
432 "--skip-unavailable" option. When used, only the available registers
435 ** The new command -trace-frame-collected dumps collected variables,
436 computed expressions, tvars, memory and registers in a traceframe.
438 ** The commands -stack-list-locals, -stack-list-arguments and
439 -stack-list-variables now accept an option "--skip-unavailable".
440 When used, only the available locals or arguments are displayed.
442 ** The -exec-run command now accepts an optional "--start" option.
443 When used, the command follows the same semantics as the "start"
444 command, stopping the program's execution at the start of its
445 main subprogram. Support for this feature can be verified using
446 the "-list-features" command, which should contain
447 "exec-run-start-option".
449 ** The new commands -catch-assert and -catch-exceptions insert
450 catchpoints stopping the program when Ada exceptions are raised.
452 ** The new command -info-ada-exceptions provides the equivalent of
453 the new "info exceptions" command.
455 * New system-wide configuration scripts
456 A GDB installation now provides scripts suitable for use as system-wide
457 configuration scripts for the following systems:
461 * GDB now supports target-assigned range stepping with remote targets.
462 This improves the performance of stepping source lines by reducing
463 the number of control packets from/to GDB. See "New remote packets"
466 * GDB now understands the element 'tvar' in the XML traceframe info.
467 It has the id of the collected trace state variables.
469 * On S/390 targets that provide the transactional-execution feature,
470 the program interruption transaction diagnostic block (TDB) is now
471 represented as a number of additional "registers" in GDB.
477 The vCont packet supports a new 'r' action, that tells the remote
478 stub to step through an address range itself, without GDB
479 involvemement at each single-step.
481 qXfer:libraries-svr4:read's annex
482 The previously unused annex of the qXfer:libraries-svr4:read packet
483 is now used to support passing an argument list. The remote stub
484 reports support for this argument list to GDB's qSupported query.
485 The defined arguments are "start" and "prev", used to reduce work
486 necessary for library list updating, resulting in significant
489 * New features in the GDB remote stub, GDBserver
491 ** GDBserver now supports target-assisted range stepping. Currently
492 enabled on x86/x86_64 GNU/Linux targets.
494 ** GDBserver now adds element 'tvar' in the XML in the reply to
495 'qXfer:traceframe-info:read'. It has the id of the collected
496 trace state variables.
498 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
501 * New 'z' formatter for printing and examining memory, this displays the
502 value as hexadecimal zero padded on the left to the size of the type.
504 * GDB can now use Windows x64 unwinding data.
506 * The "set remotebaud" command has been replaced by "set serial baud".
507 Similarly, "show remotebaud" has been replaced by "show serial baud".
508 The "set remotebaud" and "show remotebaud" commands are still available
509 to provide backward compatibility with older versions of GDB.
511 *** Changes in GDB 7.6
513 * Target record has been renamed to record-full.
514 Record/replay is now enabled with the "record full" command.
515 This also affects settings that are associated with full record/replay
516 that have been moved from "set/show record" to "set/show record full":
518 set|show record full insn-number-max
519 set|show record full stop-at-limit
520 set|show record full memory-query
522 * A new record target "record-btrace" has been added. The new target
523 uses hardware support to record the control-flow of a process. It
524 does not support replaying the execution, but it implements the
525 below new commands for investigating the recorded execution log.
526 This new recording method can be enabled using:
530 The "record-btrace" target is only available on Intel Atom processors
531 and requires a Linux kernel 2.6.32 or later.
533 * Two new commands have been added for record/replay to give information
534 about the recorded execution without having to replay the execution.
535 The commands are only supported by "record btrace".
537 record instruction-history prints the execution history at
538 instruction granularity
540 record function-call-history prints the execution history at
543 * New native configurations
545 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
546 FreeBSD/powerpc powerpc*-*-freebsd
547 x86_64/Cygwin x86_64-*-cygwin*
548 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
552 ARM AArch64 aarch64*-*-elf
553 ARM AArch64 GNU/Linux aarch64*-*-linux
554 Lynx 178 PowerPC powerpc-*-lynx*178
555 x86_64/Cygwin x86_64-*-cygwin*
556 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
558 * If the configured location of system.gdbinit file (as given by the
559 --with-system-gdbinit option at configure time) is in the
560 data-directory (as specified by --with-gdb-datadir at configure
561 time) or in one of its subdirectories, then GDB will look for the
562 system-wide init file in the directory specified by the
563 --data-directory command-line option.
565 * New command line options:
567 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
568 other initialization files, unlike -nx which disables all of them.
570 * Removed command line options
572 -epoch This was used by the gdb mode in Epoch, an ancient fork of
575 * The 'ptype' and 'whatis' commands now accept an argument to control
578 * 'info proc' now works on some core files.
582 ** Vectors can be created with gdb.Type.vector.
584 ** Python's atexit.register now works in GDB.
586 ** Types can be pretty-printed via a Python API.
588 ** Python 3 is now supported (in addition to Python 2.4 or later)
590 ** New class gdb.Architecture exposes GDB's internal representation
591 of architecture in the Python API.
593 ** New method Frame.architecture returns the gdb.Architecture object
594 corresponding to the frame's architecture.
596 * New Python-based convenience functions:
598 ** $_memeq(buf1, buf2, length)
599 ** $_streq(str1, str2)
601 ** $_regex(str, regex)
603 * The 'cd' command now defaults to using '~' (the home directory) if not
606 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
607 default for GCC since November 2000.
609 * The command 'forward-search' can now be abbreviated as 'fo'.
611 * The command 'info tracepoints' can now display 'installed on target'
612 or 'not installed on target' for each non-pending location of tracepoint.
614 * New configure options
616 --enable-libmcheck/--disable-libmcheck
617 By default, development versions are built with -lmcheck on hosts
618 that support it, in order to help track memory corruption issues.
619 Release versions, on the other hand, are built without -lmcheck
620 by default. The --enable-libmcheck/--disable-libmcheck configure
621 options allow the user to override that default.
622 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
623 This configure option allows the user to build GDB with
624 libbabeltrace using which GDB can read Common Trace Format data.
626 * New commands (for set/show, see "New options" below)
629 Catch signals. This is similar to "handle", but allows commands and
630 conditions to be attached.
633 List the BFDs known to GDB.
635 python-interactive [command]
637 Start a Python interactive prompt, or evaluate the optional command
638 and print the result of expressions.
641 "py" is a new alias for "python".
643 enable type-printer [name]...
644 disable type-printer [name]...
645 Enable or disable type printers.
649 ** For the Renesas Super-H architecture, the "regs" command has been removed
650 (has been deprecated in GDB 7.5), and "info all-registers" should be used
655 set print type methods (on|off)
656 show print type methods
657 Control whether method declarations are displayed by "ptype".
658 The default is to show them.
660 set print type typedefs (on|off)
661 show print type typedefs
662 Control whether typedef definitions are displayed by "ptype".
663 The default is to show them.
665 set filename-display basename|relative|absolute
666 show filename-display
667 Control the way in which filenames is displayed.
668 The default is "relative", which preserves previous behavior.
670 set trace-buffer-size
671 show trace-buffer-size
672 Request target to change the size of trace buffer.
674 set remote trace-buffer-size-packet auto|on|off
675 show remote trace-buffer-size-packet
676 Control the use of the remote protocol `QTBuffer:size' packet.
680 Control display of debugging messages related to ARM AArch64.
683 set debug coff-pe-read
684 show debug coff-pe-read
685 Control display of debugging messages related to reading of COFF/PE
690 Control display of debugging messages related to Mach-O symbols
693 set debug notification
694 show debug notification
695 Control display of debugging info for async remote notification.
699 ** Command parameter changes are now notified using new async record
700 "=cmd-param-changed".
701 ** Trace frame changes caused by command "tfind" are now notified using
702 new async record "=traceframe-changed".
703 ** The creation, deletion and modification of trace state variables
704 are now notified using new async records "=tsv-created",
705 "=tsv-deleted" and "=tsv-modified".
706 ** The start and stop of process record are now notified using new
707 async record "=record-started" and "=record-stopped".
708 ** Memory changes are now notified using new async record
710 ** The data-disassemble command response will include a "fullname" field
711 containing the absolute file name when source has been requested.
712 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
713 command, to allow pattern filling of memory areas.
714 ** New commands "-catch-load"/"-catch-unload" added for intercepting
715 library load/unload events.
716 ** The response to breakpoint commands and breakpoint async records
717 includes an "installed" field containing a boolean state about each
718 non-pending tracepoint location is whether installed on target or not.
719 ** Output of the "-trace-status" command includes a "trace-file" field
720 containing the name of the trace file being examined. This field is
721 optional, and only present when examining a trace file.
722 ** The "fullname" field is now always present along with the "file" field,
723 even if the file cannot be found by GDB.
725 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
726 You must have the LZMA library available when configuring GDB for this
727 feature to be enabled. For more information, see:
728 http://fedoraproject.org/wiki/Features/MiniDebugInfo
733 Set the size of trace buffer. The remote stub reports support for this
734 packet to gdb's qSupported query.
737 Enable Branch Trace Store (BTS)-based branch tracing for the current
738 thread. The remote stub reports support for this packet to gdb's
742 Disable branch tracing for the current thread. The remote stub reports
743 support for this packet to gdb's qSupported query.
746 Read the traced branches for the current thread. The remote stub
747 reports support for this packet to gdb's qSupported query.
749 *** Changes in GDB 7.5
751 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
752 for more x32 ABI info.
754 * GDB now supports access to MIPS DSP registers on Linux targets.
756 * GDB now supports debugging microMIPS binaries.
758 * The "info os" command on GNU/Linux can now display information on
759 several new classes of objects managed by the operating system:
760 "info os procgroups" lists process groups
761 "info os files" lists file descriptors
762 "info os sockets" lists internet-domain sockets
763 "info os shm" lists shared-memory regions
764 "info os semaphores" lists semaphores
765 "info os msg" lists message queues
766 "info os modules" lists loaded kernel modules
768 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
769 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
770 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
771 options and inspect the probe arguments using the new $_probe_arg family
772 of convenience variables. You can obtain more information about SystemTap
773 in <http://sourceware.org/systemtap/>.
775 * GDB now supports reversible debugging on ARM, it allows you to
776 debug basic ARM and THUMB instructions, and provides
777 record/replay support.
779 * The option "symbol-reloading" has been deleted as it is no longer used.
783 ** GDB commands implemented in Python can now be put in command class
786 ** The "maint set python print-stack on|off" is now deleted.
788 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
789 apply "flag enum"-style pretty-printing to any enum.
791 ** gdb.lookup_symbol can now work when there is no current frame.
793 ** gdb.Symbol now has a 'line' attribute, holding the line number in
794 the source at which the symbol was defined.
796 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
797 method 'value'. The former indicates whether the symbol needs a
798 frame in order to compute its value, and the latter computes the
801 ** A new method 'referenced_value' on gdb.Value objects which can
802 dereference pointer as well as C++ reference values.
804 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
805 which return the global and static blocks (as gdb.Block objects),
806 of the underlying symbol table, respectively.
808 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
809 object associated with a PC value.
811 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
812 of the address range occupied by code for the current source line.
814 * Go language support.
815 GDB now supports debugging programs written in the Go programming
818 * GDBserver now supports stdio connections.
819 E.g. (gdb) target remote | ssh myhost gdbserver - hello
821 * The binary "gdbtui" can no longer be built or installed.
822 Use "gdb -tui" instead.
824 * GDB will now print "flag" enums specially. A flag enum is one where
825 all the enumerator values have no bits in common when pairwise
826 "and"ed. When printing a value whose type is a flag enum, GDB will
827 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
828 (gdb) print (enum E) 3
831 * The filename part of a linespec will now match trailing components
832 of a source file name. For example, "break gcc/expr.c:1000" will
833 now set a breakpoint in build/gcc/expr.c, but not
836 * The "info proc" and "generate-core-file" commands will now also
837 work on remote targets connected to GDBserver on Linux.
839 * The command "info catch" has been removed. It has been disabled
842 * The "catch exception" and "catch assert" commands now accept
843 a condition at the end of the command, much like the "break"
844 command does. For instance:
846 (gdb) catch exception Constraint_Error if Barrier = True
848 Previously, it was possible to add a condition to such catchpoints,
849 but it had to be done as a second step, after the catchpoint had been
850 created, using the "condition" command.
852 * The "info static-tracepoint-marker" command will now also work on
853 native Linux targets with in-process agent.
855 * GDB can now set breakpoints on inlined functions.
857 * The .gdb_index section has been updated to include symbols for
858 inlined functions. GDB will ignore older .gdb_index sections by
859 default, which could cause symbol files to be loaded more slowly
860 until their .gdb_index sections can be recreated. The new command
861 "set use-deprecated-index-sections on" will cause GDB to use any older
862 .gdb_index sections it finds. This will restore performance, but the
863 ability to set breakpoints on inlined functions will be lost in symbol
864 files with older .gdb_index sections.
866 The .gdb_index section has also been updated to record more information
867 about each symbol. This speeds up the "info variables", "info functions"
868 and "info types" commands when used with programs having the .gdb_index
869 section, as well as speeding up debugging with shared libraries using
870 the .gdb_index section.
872 * Ada support for GDB/MI Variable Objects has been added.
874 * GDB can now support 'breakpoint always-inserted mode' in 'record'
879 ** New command -info-os is the MI equivalent of "info os".
881 ** Output logs ("set logging" and related) now include MI output.
885 ** "set use-deprecated-index-sections on|off"
886 "show use-deprecated-index-sections on|off"
887 Controls the use of deprecated .gdb_index sections.
889 ** "catch load" and "catch unload" can be used to stop when a shared
890 library is loaded or unloaded, respectively.
892 ** "enable count" can be used to auto-disable a breakpoint after
895 ** "info vtbl" can be used to show the virtual method tables for
896 C++ and Java objects.
898 ** "explore" and its sub commands "explore value" and "explore type"
899 can be used to recursively explore values and types of
900 expressions. These commands are available only if GDB is
901 configured with '--with-python'.
903 ** "info auto-load" shows status of all kinds of auto-loaded files,
904 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
905 sequences of commands files, "info auto-load python-scripts"
906 shows status of auto-loading Python script files,
907 "info auto-load local-gdbinit" shows status of loading init file
908 (.gdbinit) from current directory and "info auto-load libthread-db" shows
909 status of inferior specific thread debugging shared library loading.
911 ** "info auto-load-scripts", "set auto-load-scripts on|off"
912 and "show auto-load-scripts" commands have been deprecated, use their
913 "info auto-load python-scripts", "set auto-load python-scripts on|off"
914 and "show auto-load python-scripts" counterparts instead.
916 ** "dprintf location,format,args..." creates a dynamic printf, which
917 is basically a breakpoint that does a printf and immediately
918 resumes your program's execution, so it is like a printf that you
919 can insert dynamically at runtime instead of at compiletime.
921 ** "set print symbol"
923 Controls whether GDB attempts to display the symbol, if any,
924 corresponding to addresses it prints. This defaults to "on", but
925 you can set it to "off" to restore GDB's previous behavior.
927 * Deprecated commands
929 ** For the Renesas Super-H architecture, the "regs" command has been
930 deprecated, and "info all-registers" should be used instead.
934 Renesas RL78 rl78-*-elf
935 HP OpenVMS ia64 ia64-hp-openvms*
937 * GDBserver supports evaluation of breakpoint conditions. When
938 support is advertised by GDBserver, GDB may be told to send the
939 breakpoint conditions in bytecode form to GDBserver. GDBserver
940 will only report the breakpoint trigger to GDB when its condition
946 show mips compression
947 Select the compressed ISA encoding used in functions that have no symbol
948 information available. The encoding can be set to either of:
951 and is updated automatically from ELF file flags if available.
953 set breakpoint condition-evaluation
954 show breakpoint condition-evaluation
955 Control whether breakpoint conditions are evaluated by GDB ("host") or by
956 GDBserver ("target"). Default option "auto" chooses the most efficient
958 This option can improve debugger efficiency depending on the speed of the
962 Disable auto-loading globally.
965 Show auto-loading setting of all kinds of auto-loaded files.
967 set auto-load gdb-scripts on|off
968 show auto-load gdb-scripts
969 Control auto-loading of GDB canned sequences of commands files.
971 set auto-load python-scripts on|off
972 show auto-load python-scripts
973 Control auto-loading of Python script files.
975 set auto-load local-gdbinit on|off
976 show auto-load local-gdbinit
977 Control loading of init file (.gdbinit) from current directory.
979 set auto-load libthread-db on|off
980 show auto-load libthread-db
981 Control auto-loading of inferior specific thread debugging shared library.
983 set auto-load scripts-directory <dir1>[:<dir2>...]
984 show auto-load scripts-directory
985 Set a list of directories from which to load auto-loaded scripts.
986 Automatically loaded Python scripts and GDB scripts are located in one
987 of the directories listed by this option.
988 The delimiter (':' above) may differ according to the host platform.
990 set auto-load safe-path <dir1>[:<dir2>...]
991 show auto-load safe-path
992 Set a list of directories from which it is safe to auto-load files.
993 The delimiter (':' above) may differ according to the host platform.
995 set debug auto-load on|off
997 Control display of debugging info for auto-loading the files above.
999 set dprintf-style gdb|call|agent
1001 Control the way in which a dynamic printf is performed; "gdb"
1002 requests a GDB printf command, while "call" causes dprintf to call a
1003 function in the inferior. "agent" requests that the target agent
1004 (such as GDBserver) do the printing.
1006 set dprintf-function <expr>
1007 show dprintf-function
1008 set dprintf-channel <expr>
1009 show dprintf-channel
1010 Set the function and optional first argument to the call when using
1011 the "call" style of dynamic printf.
1013 set disconnected-dprintf on|off
1014 show disconnected-dprintf
1015 Control whether agent-style dynamic printfs continue to be in effect
1016 after GDB disconnects.
1018 * New configure options
1020 --with-auto-load-dir
1021 Configure default value for the 'set auto-load scripts-directory'
1022 setting above. It defaults to '$debugdir:$datadir/auto-load',
1023 $debugdir representing global debugging info directories (available
1024 via 'show debug-file-directory') and $datadir representing GDB's data
1025 directory (available via 'show data-directory').
1027 --with-auto-load-safe-path
1028 Configure default value for the 'set auto-load safe-path' setting
1029 above. It defaults to the --with-auto-load-dir setting.
1031 --without-auto-load-safe-path
1032 Set 'set auto-load safe-path' to '/', effectively disabling this
1035 * New remote packets
1037 z0/z1 conditional breakpoints extension
1039 The z0/z1 breakpoint insertion packets have been extended to carry
1040 a list of conditional expressions over to the remote stub depending on the
1041 condition evaluation mode. The use of this extension can be controlled
1042 via the "set remote conditional-breakpoints-packet" command.
1046 Specify the signals which the remote stub may pass to the debugged
1047 program without GDB involvement.
1049 * New command line options
1051 --init-command=FILE, -ix Like --command, -x but execute it
1052 before loading inferior.
1053 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1054 execute it before loading inferior.
1056 *** Changes in GDB 7.4
1058 * GDB now handles ambiguous linespecs more consistently; the existing
1059 FILE:LINE support has been expanded to other types of linespecs. A
1060 breakpoint will now be set on all matching locations in all
1061 inferiors, and locations will be added or removed according to
1064 * GDB now allows you to skip uninteresting functions and files when
1065 stepping with the "skip function" and "skip file" commands.
1067 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1068 and "show remote hardware-watchpoint-length-limit". These allows to
1069 set or show the maximum length limit (in bytes) of a remote
1070 target hardware watchpoint.
1072 This allows e.g. to use "unlimited" hardware watchpoints with the
1073 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1074 watchpoints are slower than real hardware watchpoints but are
1075 significantly faster than gdb software watchpoints.
1079 ** The register_pretty_printer function in module gdb.printing now takes
1080 an optional `replace' argument. If True, the new printer replaces any
1083 ** The "maint set python print-stack on|off" command has been
1084 deprecated and will be deleted in GDB 7.5.
1085 A new command: "set python print-stack none|full|message" has
1086 replaced it. Additionally, the default for "print-stack" is
1087 now "message", which just prints the error message without
1090 ** A prompt substitution hook (prompt_hook) is now available to the
1093 ** A new Python module, gdb.prompt has been added to the GDB Python
1094 modules library. This module provides functionality for
1095 escape sequences in prompts (used by set/show
1096 extended-prompt). These escape sequences are replaced by their
1097 corresponding value.
1099 ** Python commands and convenience-functions located in
1100 'data-directory'/python/gdb/command and
1101 'data-directory'/python/gdb/function are now automatically loaded
1104 ** Blocks now provide four new attributes. global_block and
1105 static_block will return the global and static blocks
1106 respectively. is_static and is_global are boolean attributes
1107 that indicate if the block is one of those two types.
1109 ** Symbols now provide the "type" attribute, the type of the symbol.
1111 ** The "gdb.breakpoint" function has been deprecated in favor of
1114 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1115 of a function. This class is based on the "finish" command
1116 available in the CLI.
1118 ** Type objects for struct and union types now allow access to
1119 the fields using standard Python dictionary (mapping) methods.
1120 For example, "some_type['myfield']" now works, as does
1121 "some_type.items()".
1123 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1126 ** A new function, "deep_items" has been added to the gdb.types
1127 module in the GDB Python modules library. This function returns
1128 an iterator over the fields of a struct or union type. Unlike
1129 the standard Python "iteritems" method, it will recursively traverse
1130 any anonymous fields.
1134 ** "*stopped" events can report several new "reason"s, such as
1137 ** Breakpoint changes are now notified using new async records, like
1138 "=breakpoint-modified".
1140 ** New command -ada-task-info.
1142 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1143 $sdir specifies the default system locations of shared libraries.
1144 $pdir specifies the directory where the libpthread used by the application
1147 GDB no longer looks in $sdir and $pdir after it has searched the directories
1148 mentioned in libthread-db-search-path. If you want to search those
1149 directories, they must be specified in libthread-db-search-path.
1150 The default value of libthread-db-search-path on GNU/Linux and Solaris
1151 systems is now "$sdir:$pdir".
1153 $pdir is not supported by gdbserver, it is currently ignored.
1154 $sdir is supported by gdbserver.
1156 * New configure option --with-iconv-bin.
1157 When using the internationalization support like the one in the GNU C
1158 library, GDB will invoke the "iconv" program to get a list of supported
1159 character sets. If this program lives in a non-standard location, one can
1160 use this option to specify where to find it.
1162 * When natively debugging programs on PowerPC BookE processors running
1163 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1164 watchpoints, which specify a mask in addition to an address to watch.
1165 The mask specifies that some bits of an address (the bits which are
1166 reset in the mask) should be ignored when matching the address accessed
1167 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1168 section in the user manual for more details.
1170 * The new option --once causes GDBserver to stop listening for connections once
1171 the first connection is made. The listening port used by GDBserver will
1172 become available after that.
1174 * New commands "info macros" and "alias" have been added.
1176 * New function parameters suffix @entry specifies value of function parameter
1177 at the time the function got called. Entry values are available only since
1183 "!" is now an alias of the "shell" command.
1184 Note that no space is needed between "!" and SHELL COMMAND.
1188 watch EXPRESSION mask MASK_VALUE
1189 The watch command now supports the mask argument which allows creation
1190 of masked watchpoints, if the current architecture supports this feature.
1192 info auto-load-scripts [REGEXP]
1193 This command was formerly named "maintenance print section-scripts".
1194 It is now generally useful and is no longer a maintenance-only command.
1196 info macro [-all] [--] MACRO
1197 The info macro command has new options `-all' and `--'. The first for
1198 printing all definitions of a macro. The second for explicitly specifying
1199 the end of arguments and the beginning of the macro name in case the macro
1200 name starts with a hyphen.
1202 collect[/s] EXPRESSIONS
1203 The tracepoint collect command now takes an optional modifier "/s"
1204 that directs it to dereference pointer-to-character types and
1205 collect the bytes of memory up to a zero byte. The behavior is
1206 similar to what you see when you use the regular print command on a
1207 string. An optional integer following the "/s" sets a bound on the
1208 number of bytes that will be collected.
1211 The trace start command now interprets any supplied arguments as a
1212 note to be recorded with the trace run, with an effect similar to
1213 setting the variable trace-notes.
1216 The trace stop command now interprets any arguments as a note to be
1217 mentioned along with the tstatus report that the trace was stopped
1218 with a command. The effect is similar to setting the variable
1221 * Tracepoints can now be enabled and disabled at any time after a trace
1222 experiment has been started using the standard "enable" and "disable"
1223 commands. It is now possible to start a trace experiment with no enabled
1224 tracepoints; GDB will display a warning, but will allow the experiment to
1225 begin, assuming that tracepoints will be enabled as needed while the trace
1228 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1229 locations with 4-byte instructions, when they were previously
1230 limited to locations with instructions of 5 bytes or longer.
1234 set debug dwarf2-read
1235 show debug dwarf2-read
1236 Turns on or off display of debugging messages related to reading
1237 DWARF debug info. The default is off.
1239 set debug symtab-create
1240 show debug symtab-create
1241 Turns on or off display of debugging messages related to symbol table
1242 creation. The default is off.
1245 show extended-prompt
1246 Set the GDB prompt, and allow escape sequences to be inserted to
1247 display miscellaneous information (see 'help set extended-prompt'
1248 for the list of sequences). This prompt (and any information
1249 accessed through the escape sequences) is updated every time the
1250 prompt is displayed.
1252 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1253 show print entry-values
1254 Set printing of frame argument values at function entry. In some cases
1255 GDB can determine the value of function argument which was passed by the
1256 function caller, even if the value was modified inside the called function.
1258 set debug entry-values
1259 show debug entry-values
1260 Control display of debugging info for determining frame argument values at
1261 function entry and virtual tail call frames.
1263 set basenames-may-differ
1264 show basenames-may-differ
1265 Set whether a source file may have multiple base names.
1266 (A "base name" is the name of a file with the directory part removed.
1267 Example: The base name of "/home/user/hello.c" is "hello.c".)
1268 If set, GDB will canonicalize file names (e.g., expand symlinks)
1269 before comparing them. Canonicalization is an expensive operation,
1270 but it allows the same file be known by more than one base name.
1271 If not set (the default), all source files are assumed to have just
1272 one base name, and gdb will do file name comparisons more efficiently.
1278 Set a user name and notes for the current and any future trace runs.
1279 This is useful for long-running and/or disconnected traces, to
1280 inform others (or yourself) as to who is running the trace, supply
1281 contact information, or otherwise explain what is going on.
1283 set trace-stop-notes
1284 show trace-stop-notes
1285 Set a note attached to the trace run, that is displayed when the
1286 trace has been stopped by a tstop command. This is useful for
1287 instance as an explanation, if you are stopping a trace run that was
1288 started by someone else.
1290 * New remote packets
1294 Dynamically enable a tracepoint in a started trace experiment.
1298 Dynamically disable a tracepoint in a started trace experiment.
1302 Set the user and notes of the trace run.
1306 Query the current status of a tracepoint.
1310 Query the minimum length of instruction at which a fast tracepoint may
1313 * Dcache size (number of lines) and line-size are now runtime-configurable
1314 via "set dcache line" and "set dcache line-size" commands.
1318 Texas Instruments TMS320C6x tic6x-*-*
1322 Renesas RL78 rl78-*-elf
1324 *** Changes in GDB 7.3.1
1326 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1328 *** Changes in GDB 7.3
1330 * GDB has a new command: "thread find [REGEXP]".
1331 It finds the thread id whose name, target id, or thread extra info
1332 matches the given regular expression.
1334 * The "catch syscall" command now works on mips*-linux* targets.
1336 * The -data-disassemble MI command now supports modes 2 and 3 for
1337 dumping the instruction opcodes.
1339 * New command line options
1341 -data-directory DIR Specify DIR as the "data-directory".
1342 This is mostly for testing purposes.
1344 * The "maint set python auto-load on|off" command has been renamed to
1345 "set auto-load-scripts on|off".
1347 * GDB has a new command: "set directories".
1348 It is like the "dir" command except that it replaces the
1349 source path list instead of augmenting it.
1351 * GDB now understands thread names.
1353 On GNU/Linux, "info threads" will display the thread name as set by
1354 prctl or pthread_setname_np.
1356 There is also a new command, "thread name", which can be used to
1357 assign a name internally for GDB to display.
1360 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1361 has been integrated into GDB.
1365 ** The function gdb.Write now accepts an optional keyword 'stream'.
1366 This keyword, when provided, will direct the output to either
1367 stdout, stderr, or GDB's logging output.
1369 ** Parameters can now be be sub-classed in Python, and in particular
1370 you may implement the get_set_doc and get_show_doc functions.
1371 This improves how Parameter set/show documentation is processed
1372 and allows for more dynamic content.
1374 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1375 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1376 have an is_valid method.
1378 ** Breakpoints can now be sub-classed in Python, and in particular
1379 you may implement a 'stop' function that is executed each time
1380 the inferior reaches that breakpoint.
1382 ** New function gdb.lookup_global_symbol looks up a global symbol.
1384 ** GDB values in Python are now callable if the value represents a
1385 function. For example, if 'some_value' represents a function that
1386 takes two integer parameters and returns a value, you can call
1387 that function like so:
1389 result = some_value (10,20)
1391 ** Module gdb.types has been added.
1392 It contains a collection of utilities for working with gdb.Types objects:
1393 get_basic_type, has_field, make_enum_dict.
1395 ** Module gdb.printing has been added.
1396 It contains utilities for writing and registering pretty-printers.
1397 New classes: PrettyPrinter, SubPrettyPrinter,
1398 RegexpCollectionPrettyPrinter.
1399 New function: register_pretty_printer.
1401 ** New commands "info pretty-printers", "enable pretty-printer" and
1402 "disable pretty-printer" have been added.
1404 ** gdb.parameter("directories") is now available.
1406 ** New function gdb.newest_frame returns the newest frame in the
1409 ** The gdb.InferiorThread class has a new "name" attribute. This
1410 holds the thread's name.
1412 ** Python Support for Inferior events.
1413 Python scripts can add observers to be notified of events
1414 occurring in the process being debugged.
1415 The following events are currently supported:
1416 - gdb.events.cont Continue event.
1417 - gdb.events.exited Inferior exited event.
1418 - gdb.events.stop Signal received, and Breakpoint hit events.
1422 ** GDB now puts template parameters in scope when debugging in an
1423 instantiation. For example, if you have:
1425 template<int X> int func (void) { return X; }
1427 then if you step into func<5>, "print X" will show "5". This
1428 feature requires proper debuginfo support from the compiler; it
1429 was added to GCC 4.5.
1431 ** The motion commands "next", "finish", "until", and "advance" now
1432 work better when exceptions are thrown. In particular, GDB will
1433 no longer lose control of the inferior; instead, the GDB will
1434 stop the inferior at the point at which the exception is caught.
1435 This functionality requires a change in the exception handling
1436 code that was introduced in GCC 4.5.
1438 * GDB now follows GCC's rules on accessing volatile objects when
1439 reading or writing target state during expression evaluation.
1440 One notable difference to prior behavior is that "print x = 0"
1441 no longer generates a read of x; the value of the assignment is
1442 now always taken directly from the value being assigned.
1444 * GDB now has some support for using labels in the program's source in
1445 linespecs. For instance, you can use "advance label" to continue
1446 execution to a label.
1448 * GDB now has support for reading and writing a new .gdb_index
1449 section. This section holds a fast index of DWARF debugging
1450 information and can be used to greatly speed up GDB startup and
1451 operation. See the documentation for `save gdb-index' for details.
1453 * The "watch" command now accepts an optional "-location" argument.
1454 When used, this causes GDB to watch the memory referred to by the
1455 expression. Such a watchpoint is never deleted due to it going out
1458 * GDB now supports thread debugging of core dumps on GNU/Linux.
1460 GDB now activates thread debugging using the libthread_db library
1461 when debugging GNU/Linux core dumps, similarly to when debugging
1462 live processes. As a result, when debugging a core dump file, GDB
1463 is now able to display pthread_t ids of threads. For example, "info
1464 threads" shows the same output as when debugging the process when it
1465 was live. In earlier releases, you'd see something like this:
1468 * 1 LWP 6780 main () at main.c:10
1470 While now you see this:
1473 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1475 It is also now possible to inspect TLS variables when debugging core
1478 When debugging a core dump generated on a machine other than the one
1479 used to run GDB, you may need to point GDB at the correct
1480 libthread_db library with the "set libthread-db-search-path"
1481 command. See the user manual for more details on this command.
1483 * When natively debugging programs on PowerPC BookE processors running
1484 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1485 which stop execution of the inferior whenever it executes an instruction
1486 at any address within the specified range. See the "PowerPC Embedded"
1487 section in the user manual for more details.
1489 * New features in the GDB remote stub, GDBserver
1491 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1492 and i686 LynxOS (version 5.x).
1494 ** GDBserver is now supported on Blackfin Linux.
1496 * New native configurations
1498 ia64 HP-UX ia64-*-hpux*
1502 Analog Devices, Inc. Blackfin Processor bfin-*
1504 * Ada task switching is now supported on sparc-elf targets when
1505 debugging a program using the Ravenscar Profile. For more information,
1506 see the "Tasking Support when using the Ravenscar Profile" section
1507 in the GDB user manual.
1509 * Guile support was removed.
1511 * New features in the GNU simulator
1513 ** The --map-info flag lists all known core mappings.
1515 ** CFI flashes may be simulated via the "cfi" device.
1517 *** Changes in GDB 7.2
1519 * Shared library support for remote targets by default
1521 When GDB is configured for a generic, non-OS specific target, like
1522 for example, --target=arm-eabi or one of the many *-*-elf targets,
1523 GDB now queries remote stubs for loaded shared libraries using the
1524 `qXfer:libraries:read' packet. Previously, shared library support
1525 was always disabled for such configurations.
1529 ** Argument Dependent Lookup (ADL)
1531 In C++ ADL lookup directs function search to the namespaces of its
1532 arguments even if the namespace has not been imported.
1542 Here the compiler will search for `foo' in the namespace of 'b'
1543 and find A::foo. GDB now supports this. This construct is commonly
1544 used in the Standard Template Library for operators.
1546 ** Improved User Defined Operator Support
1548 In addition to member operators, GDB now supports lookup of operators
1549 defined in a namespace and imported with a `using' directive, operators
1550 defined in the global scope, operators imported implicitly from an
1551 anonymous namespace, and the ADL operators mentioned in the previous
1553 GDB now also supports proper overload resolution for all the previously
1554 mentioned flavors of operators.
1556 ** static const class members
1558 Printing of static const class members that are initialized in the
1559 class definition has been fixed.
1561 * Windows Thread Information Block access.
1563 On Windows targets, GDB now supports displaying the Windows Thread
1564 Information Block (TIB) structure. This structure is visible either
1565 by using the new command `info w32 thread-information-block' or, by
1566 dereferencing the new convenience variable named `$_tlb', a
1567 thread-specific pointer to the TIB. This feature is also supported
1568 when remote debugging using GDBserver.
1570 * Static tracepoints
1572 Static tracepoints are calls in the user program into a tracing
1573 library. One such library is a port of the LTTng kernel tracer to
1574 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1575 When debugging with GDBserver, GDB now supports combining the GDB
1576 tracepoint machinery with such libraries. For example: the user can
1577 use GDB to probe a static tracepoint marker (a call from the user
1578 program into the tracing library) with the new "strace" command (see
1579 "New commands" below). This creates a "static tracepoint" in the
1580 breakpoint list, that can be manipulated with the same feature set
1581 as fast and regular tracepoints. E.g., collect registers, local and
1582 global variables, collect trace state variables, and define
1583 tracepoint conditions. In addition, the user can collect extra
1584 static tracepoint marker specific data, by collecting the new
1585 $_sdata internal variable. When analyzing the trace buffer, you can
1586 inspect $_sdata like any other variable available to GDB. For more
1587 information, see the "Tracepoints" chapter in GDB user manual. New
1588 remote packets have been defined to support static tracepoints, see
1589 the "New remote packets" section below.
1591 * Better reconstruction of tracepoints after disconnected tracing
1593 GDB will attempt to download the original source form of tracepoint
1594 definitions when starting a trace run, and then will upload these
1595 upon reconnection to the target, resulting in a more accurate
1596 reconstruction of the tracepoints that are in use on the target.
1600 You can now exercise direct control over the ways that GDB can
1601 affect your program. For instance, you can disallow the setting of
1602 breakpoints, so that the program can run continuously (assuming
1603 non-stop mode). In addition, the "observer" variable is available
1604 to switch all of the different controls; in observer mode, GDB
1605 cannot affect the target's behavior at all, which is useful for
1606 tasks like diagnosing live systems in the field.
1608 * The new convenience variable $_thread holds the number of the
1611 * New remote packets
1615 Return the address of the Windows Thread Information Block of a given thread.
1619 In response to several of the tracepoint packets, the target may now
1620 also respond with a number of intermediate `qRelocInsn' request
1621 packets before the final result packet, to have GDB handle
1622 relocating an instruction to execute at a different address. This
1623 is particularly useful for stubs that support fast tracepoints. GDB
1624 reports support for this feature in the qSupported packet.
1628 List static tracepoint markers in the target program.
1632 List static tracepoint markers at a given address in the target
1635 qXfer:statictrace:read
1637 Read the static trace data collected (by a `collect $_sdata'
1638 tracepoint action). The remote stub reports support for this packet
1639 to gdb's qSupported query.
1643 Send the current settings of GDB's permission flags.
1647 Send part of the source (textual) form of a tracepoint definition,
1648 which includes location, conditional, and action list.
1650 * The source command now accepts a -s option to force searching for the
1651 script in the source search path even if the script name specifies
1654 * New features in the GDB remote stub, GDBserver
1656 - GDBserver now support tracepoints (including fast tracepoints, and
1657 static tracepoints). The feature is currently supported by the
1658 i386-linux and amd64-linux builds. See the "Tracepoints support
1659 in gdbserver" section in the manual for more information.
1661 GDBserver JIT compiles the tracepoint's conditional agent
1662 expression bytecode into native code whenever possible for low
1663 overhead dynamic tracepoints conditionals. For such tracepoints,
1664 an expression that examines program state is evaluated when the
1665 tracepoint is reached, in order to determine whether to capture
1666 trace data. If the condition is simple and false, processing the
1667 tracepoint finishes very quickly and no data is gathered.
1669 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1670 for static tracepoints support.
1672 - GDBserver now supports x86_64 Windows 64-bit debugging.
1674 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1675 it understands register description.
1677 * The --batch flag now disables pagination and queries.
1679 * X86 general purpose registers
1681 GDB now supports reading/writing byte, word and double-word x86
1682 general purpose registers directly. This means you can use, say,
1683 $ah or $ax to refer, respectively, to the byte register AH and
1684 16-bit word register AX that are actually portions of the 32-bit
1685 register EAX or 64-bit register RAX.
1687 * The `commands' command now accepts a range of breakpoints to modify.
1688 A plain `commands' following a command that creates multiple
1689 breakpoints affects all the breakpoints set by that command. This
1690 applies to breakpoints set by `rbreak', and also applies when a
1691 single `break' command creates multiple breakpoints (e.g.,
1692 breakpoints on overloaded c++ functions).
1694 * The `rbreak' command now accepts a filename specification as part of
1695 its argument, limiting the functions selected by the regex to those
1696 in the specified file.
1698 * Support for remote debugging Windows and SymbianOS shared libraries
1699 from Unix hosts has been improved. Non Windows GDB builds now can
1700 understand target reported file names that follow MS-DOS based file
1701 system semantics, such as file names that include drive letters and
1702 use the backslash character as directory separator. This makes it
1703 possible to transparently use the "set sysroot" and "set
1704 solib-search-path" on Unix hosts to point as host copies of the
1705 target's shared libraries. See the new command "set
1706 target-file-system-kind" described below, and the "Commands to
1707 specify files" section in the user manual for more information.
1711 eval template, expressions...
1712 Convert the values of one or more expressions under the control
1713 of the string template to a command line, and call it.
1715 set target-file-system-kind unix|dos-based|auto
1716 show target-file-system-kind
1717 Set or show the assumed file system kind for target reported file
1720 save breakpoints <filename>
1721 Save all current breakpoint definitions to a file suitable for use
1722 in a later debugging session. To read the saved breakpoint
1723 definitions, use the `source' command.
1725 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1728 info static-tracepoint-markers
1729 Display information about static tracepoint markers in the target.
1731 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1732 Define a static tracepoint by probing a marker at the given
1733 function, line, address, or marker ID.
1737 Enable and disable observer mode.
1739 set may-write-registers on|off
1740 set may-write-memory on|off
1741 set may-insert-breakpoints on|off
1742 set may-insert-tracepoints on|off
1743 set may-insert-fast-tracepoints on|off
1744 set may-interrupt on|off
1745 Set individual permissions for GDB effects on the target. Note that
1746 some of these settings can have undesirable or surprising
1747 consequences, particularly when changed in the middle of a session.
1748 For instance, disabling the writing of memory can prevent
1749 breakpoints from being inserted, cause single-stepping to fail, or
1750 even crash your program, if you disable after breakpoints have been
1751 inserted. However, GDB should not crash.
1753 set record memory-query on|off
1754 show record memory-query
1755 Control whether to stop the inferior if memory changes caused
1756 by an instruction cannot be recorded.
1761 The disassemble command now supports "start,+length" form of two arguments.
1765 ** GDB now provides a new directory location, called the python directory,
1766 where Python scripts written for GDB can be installed. The location
1767 of that directory is <data-directory>/python, where <data-directory>
1768 is the GDB data directory. For more details, see section `Scripting
1769 GDB using Python' in the manual.
1771 ** The GDB Python API now has access to breakpoints, symbols, symbol
1772 tables, program spaces, inferiors, threads and frame's code blocks.
1773 Additionally, GDB Parameters can now be created from the API, and
1774 manipulated via set/show in the CLI.
1776 ** New functions gdb.target_charset, gdb.target_wide_charset,
1777 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1779 ** New exception gdb.GdbError.
1781 ** Pretty-printers are now also looked up in the current program space.
1783 ** Pretty-printers can now be individually enabled and disabled.
1785 ** GDB now looks for names of Python scripts to auto-load in a
1786 special section named `.debug_gdb_scripts', in addition to looking
1787 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1789 * Tracepoint actions were unified with breakpoint commands. In particular,
1790 there are no longer differences in "info break" output for breakpoints and
1791 tracepoints and the "commands" command can be used for both tracepoints and
1792 regular breakpoints.
1796 ARM Symbian arm*-*-symbianelf*
1798 * D language support.
1799 GDB now supports debugging programs written in the D programming
1802 * GDB now supports the extended ptrace interface for PowerPC which is
1803 available since Linux kernel version 2.6.34. This automatically enables
1804 any hardware breakpoints and additional hardware watchpoints available in
1805 the processor. The old ptrace interface exposes just one hardware
1806 watchpoint and no hardware breakpoints.
1808 * GDB is now able to use the Data Value Compare (DVC) register available on
1809 embedded PowerPC processors to implement in hardware simple watchpoint
1810 conditions of the form:
1812 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1814 This works in native GDB running on Linux kernels with the extended ptrace
1815 interface mentioned above.
1817 *** Changes in GDB 7.1
1821 ** Namespace Support
1823 GDB now supports importing of namespaces in C++. This enables the
1824 user to inspect variables from imported namespaces. Support for
1825 namepace aliasing has also been added. So, if a namespace is
1826 aliased in the current scope (e.g. namepace C=A; ) the user can
1827 print variables using the alias (e.g. (gdb) print C::x).
1831 All known bugs relating to the printing of virtual base class were
1832 fixed. It is now possible to call overloaded static methods using a
1837 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1838 and reinterpret_cast<> are now handled by the C++ expression parser.
1842 Xilinx MicroBlaze microblaze-*-*
1847 Xilinx MicroBlaze microblaze
1850 * Multi-program debugging.
1852 GDB now has support for multi-program (a.k.a. multi-executable or
1853 multi-exec) debugging. This allows for debugging multiple inferiors
1854 simultaneously each running a different program under the same GDB
1855 session. See "Debugging Multiple Inferiors and Programs" in the
1856 manual for more information. This implied some user visible changes
1857 in the multi-inferior support. For example, "info inferiors" now
1858 lists inferiors that are not running yet or that have exited
1859 already. See also "New commands" and "New options" below.
1861 * New tracing features
1863 GDB's tracepoint facility now includes several new features:
1865 ** Trace state variables
1867 GDB tracepoints now include support for trace state variables, which
1868 are variables managed by the target agent during a tracing
1869 experiment. They are useful for tracepoints that trigger each
1870 other, so for instance one tracepoint can count hits in a variable,
1871 and then a second tracepoint has a condition that is true when the
1872 count reaches a particular value. Trace state variables share the
1873 $-syntax of GDB convenience variables, and can appear in both
1874 tracepoint actions and condition expressions. Use the "tvariable"
1875 command to create, and "info tvariables" to view; see "Trace State
1876 Variables" in the manual for more detail.
1880 GDB now includes an option for defining fast tracepoints, which
1881 targets may implement more efficiently, such as by installing a jump
1882 into the target agent rather than a trap instruction. The resulting
1883 speedup can be by two orders of magnitude or more, although the
1884 tradeoff is that some program locations on some target architectures
1885 might not allow fast tracepoint installation, for instance if the
1886 instruction to be replaced is shorter than the jump. To request a
1887 fast tracepoint, use the "ftrace" command, with syntax identical to
1888 the regular trace command.
1890 ** Disconnected tracing
1892 It is now possible to detach GDB from the target while it is running
1893 a trace experiment, then reconnect later to see how the experiment
1894 is going. In addition, a new variable disconnected-tracing lets you
1895 tell the target agent whether to continue running a trace if the
1896 connection is lost unexpectedly.
1900 GDB now has the ability to save the trace buffer into a file, and
1901 then use that file as a target, similarly to you can do with
1902 corefiles. You can select trace frames, print data that was
1903 collected in them, and use tstatus to display the state of the
1904 tracing run at the moment that it was saved. To create a trace
1905 file, use "tsave <filename>", and to use it, do "target tfile
1908 ** Circular trace buffer
1910 You can ask the target agent to handle the trace buffer as a
1911 circular buffer, discarding the oldest trace frames to make room for
1912 newer ones, by setting circular-trace-buffer to on. This feature may
1913 not be available for all target agents.
1918 The disassemble command, when invoked with two arguments, now requires
1919 the arguments to be comma-separated.
1922 The info variables command now displays variable definitions. Files
1923 which only declare a variable are not shown.
1926 The source command is now capable of sourcing Python scripts.
1927 This feature is dependent on the debugger being build with Python
1930 Related to this enhancement is also the introduction of a new command
1931 "set script-extension" (see below).
1933 * New commands (for set/show, see "New options" below)
1935 record save [<FILENAME>]
1936 Save a file (in core file format) containing the process record
1937 execution log for replay debugging at a later time.
1939 record restore <FILENAME>
1940 Restore the process record execution log that was saved at an
1941 earlier time, for replay debugging.
1943 add-inferior [-copies <N>] [-exec <FILENAME>]
1946 clone-inferior [-copies <N>] [ID]
1947 Make a new inferior ready to execute the same program another
1948 inferior has loaded.
1953 maint info program-spaces
1954 List the program spaces loaded into GDB.
1956 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1957 show remote interrupt-sequence
1958 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1959 as the sequence to the remote target in order to interrupt the execution.
1960 Ctrl-C is a default. Some system prefers BREAK which is high level of
1961 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1962 Magic SysRq g. It is BREAK signal and character 'g'.
1964 set remote interrupt-on-connect [on | off]
1965 show remote interrupt-on-connect
1966 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1967 remote target when gdb connects to it. This is needed when you debug
1970 set remotebreak [on | off]
1972 Deprecated. Use "set/show remote interrupt-sequence" instead.
1974 tvariable $NAME [ = EXP ]
1975 Create or modify a trace state variable.
1978 List trace state variables and their values.
1980 delete tvariable $NAME ...
1981 Delete one or more trace state variables.
1984 Evaluate the given expressions without collecting anything into the
1985 trace buffer. (Valid in tracepoint actions only.)
1987 ftrace FN / FILE:LINE / *ADDR
1988 Define a fast tracepoint at the given function, line, or address.
1990 * New expression syntax
1992 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1993 GDB now parses 0b101010 identically with 42.
1997 set follow-exec-mode new|same
1998 show follow-exec-mode
1999 Control whether GDB reuses the same inferior across an exec call or
2000 creates a new one. This is useful to be able to restart the old
2001 executable after the inferior having done an exec call.
2003 set default-collect EXPR, ...
2004 show default-collect
2005 Define a list of expressions to be collected at each tracepoint.
2006 This is a useful way to ensure essential items are not overlooked,
2007 such as registers or a critical global variable.
2009 set disconnected-tracing
2010 show disconnected-tracing
2011 If set to 1, the target is instructed to continue tracing if it
2012 loses its connection to GDB. If 0, the target is to stop tracing
2015 set circular-trace-buffer
2016 show circular-trace-buffer
2017 If set to on, the target is instructed to use a circular trace buffer
2018 and discard the oldest trace frames instead of stopping the trace due
2019 to a full trace buffer. If set to off, the trace stops when the buffer
2020 fills up. Some targets may not support this.
2022 set script-extension off|soft|strict
2023 show script-extension
2024 If set to "off", the debugger does not perform any script language
2025 recognition, and all sourced files are assumed to be GDB scripts.
2026 If set to "soft" (the default), files are sourced according to
2027 filename extension, falling back to GDB scripts if the first
2029 If set to "strict", files are sourced according to filename extension.
2031 set ada trust-PAD-over-XVS on|off
2032 show ada trust-PAD-over-XVS
2033 If off, activate a workaround against a bug in the debugging information
2034 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2035 the GCC sources for more information about the GNAT encoding and
2036 PAD types in particular). It is always safe to set this option to
2037 off, but this introduces a slight performance penalty. The default
2040 * Python API Improvements
2042 ** GDB provides the new class gdb.LazyString. This is useful in
2043 some pretty-printing cases. The new method gdb.Value.lazy_string
2044 provides a simple way to create objects of this type.
2046 ** The fields returned by gdb.Type.fields now have an
2047 `is_base_class' attribute.
2049 ** The new method gdb.Type.range returns the range of an array type.
2051 ** The new method gdb.parse_and_eval can be used to parse and
2052 evaluate an expression.
2054 * New remote packets
2057 Define a trace state variable.
2060 Get the current value of a trace state variable.
2063 Set desired tracing behavior upon disconnection.
2066 Set the trace buffer to be linear or circular.
2069 Get data about the tracepoints currently in use.
2073 Process record now works correctly with hardware watchpoints.
2075 Multiple bug fixes have been made to the mips-irix port, making it
2076 much more reliable. In particular:
2077 - Debugging threaded applications is now possible again. Previously,
2078 GDB would hang while starting the program, or while waiting for
2079 the program to stop at a breakpoint.
2080 - Attaching to a running process no longer hangs.
2081 - An error occurring while loading a core file has been fixed.
2082 - Changing the value of the PC register now works again. This fixes
2083 problems observed when using the "jump" command, or when calling
2084 a function from GDB, or even when assigning a new value to $pc.
2085 - With the "finish" and "return" commands, the return value for functions
2086 returning a small array is now correctly printed.
2087 - It is now possible to break on shared library code which gets executed
2088 during a shared library init phase (code executed while executing
2089 their .init section). Previously, the breakpoint would have no effect.
2090 - GDB is now able to backtrace through the signal handler for
2091 non-threaded programs.
2093 PIE (Position Independent Executable) programs debugging is now supported.
2094 This includes debugging execution of PIC (Position Independent Code) shared
2095 libraries although for that, it should be possible to run such libraries as an
2098 *** Changes in GDB 7.0
2100 * GDB now has an interface for JIT compilation. Applications that
2101 dynamically generate code can create symbol files in memory and register
2102 them with GDB. For users, the feature should work transparently, and
2103 for JIT developers, the interface is documented in the GDB manual in the
2104 "JIT Compilation Interface" chapter.
2106 * Tracepoints may now be conditional. The syntax is as for
2107 breakpoints; either an "if" clause appended to the "trace" command,
2108 or the "condition" command is available. GDB sends the condition to
2109 the target for evaluation using the same bytecode format as is used
2110 for tracepoint actions.
2112 * The disassemble command now supports: an optional /r modifier, print the
2113 raw instructions in hex as well as in symbolic form, and an optional /m
2114 modifier to print mixed source+assembly.
2116 * Process record and replay
2118 In a architecture environment that supports ``process record and
2119 replay'', ``process record and replay'' target can record a log of
2120 the process execution, and replay it with both forward and reverse
2123 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2124 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2125 set execution-direction {forward|reverse}, for targets that support
2128 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2129 feature is available with a native GDB running on kernel version
2132 * GDB now has support for multi-byte and wide character sets on the
2133 target. Strings whose character type is wchar_t, char16_t, or
2134 char32_t are now correctly printed. GDB supports wide- and unicode-
2135 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2136 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2137 `printf'. This feature requires iconv to work properly; if your
2138 system does not have a working iconv, GDB can use GNU libiconv. See
2139 the installation instructions for more information.
2141 * GDB now supports automatic retrieval of shared library files from
2142 remote targets. To use this feature, specify a system root that begins
2143 with the `remote:' prefix, either via the `set sysroot' command or via
2144 the `--with-sysroot' configure-time option.
2146 * "info sharedlibrary" now takes an optional regex of libraries to show,
2147 and it now reports if a shared library has no debugging information.
2149 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2150 now complete on file names.
2152 * When completing in expressions, gdb will attempt to limit
2153 completions to allowable structure or union fields, where appropriate.
2154 For instance, consider:
2156 # struct example { int f1; double f2; };
2157 # struct example variable;
2160 If the user types TAB at the end of this command line, the available
2161 completions will be "f1" and "f2".
2163 * Inlined functions are now supported. They show up in backtraces, and
2164 the "step", "next", and "finish" commands handle them automatically.
2166 * GDB now supports the token-splicing (##) and stringification (#)
2167 operators when expanding macros. It also supports variable-arity
2170 * GDB now supports inspecting extra signal information, exported by
2171 the new $_siginfo convenience variable. The feature is currently
2172 implemented on linux ARM, i386 and amd64.
2174 * GDB can now display the VFP floating point registers and NEON vector
2175 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2176 can provide these registers (requires Linux 2.6.30 or later). Remote
2177 and simulator targets may also provide them.
2179 * New remote packets
2182 Search memory for a sequence of bytes.
2185 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2186 operation over reliable transport links. Use of this packet is
2187 controlled by the `set remote noack-packet' command.
2190 Kill the process with the specified process ID. Use this in preference
2191 to `k' when multiprocess protocol extensions are supported.
2194 Obtains additional operating system information
2198 Read or write additional signal information.
2200 * Removed remote protocol undocumented extension
2202 An undocumented extension to the remote protocol's `S' stop reply
2203 packet that permited the stub to pass a process id was removed.
2204 Remote servers should use the `T' stop reply packet instead.
2206 * GDB now supports multiple function calling conventions according to the
2207 DWARF-2 DW_AT_calling_convention function attribute.
2209 * The SH target utilizes the aforementioned change to distinguish between gcc
2210 and Renesas calling convention. It also adds the new CLI commands
2211 `set/show sh calling-convention'.
2213 * GDB can now read compressed debug sections, as produced by GNU gold
2214 with the --compress-debug-sections=zlib flag.
2216 * 64-bit core files are now supported on AIX.
2218 * Thread switching is now supported on Tru64.
2220 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2221 which will be allocated using malloc later in program execution.
2223 * The qXfer:libraries:read remote procotol packet now allows passing a
2224 list of section offsets.
2226 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2227 conditions handling signals delivered during attach or thread creation
2228 have also been fixed.
2230 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2231 From the user's standpoint, all unqualified instances of True and False
2232 are treated as the standard definitions, regardless of context.
2234 * GDB now parses C++ symbol and type names more flexibly. For
2237 template<typename T> class C { };
2240 GDB will now correctly handle all of:
2242 ptype C<char const *>
2243 ptype C<char const*>
2244 ptype C<const char *>
2245 ptype C<const char*>
2247 * New features in the GDB remote stub, gdbserver
2249 - The "--wrapper" command-line argument tells gdbserver to use a
2250 wrapper program to launch programs for debugging.
2252 - On PowerPC and S/390 targets, it is now possible to use a single
2253 gdbserver executable to debug both 32-bit and 64-bit programs.
2254 (This requires gdbserver itself to be built as a 64-bit executable.)
2256 - gdbserver uses the new noack protocol mode for TCP connections to
2257 reduce communications latency, if also supported and enabled in GDB.
2259 - Support for the sparc64-linux-gnu target is now included in
2262 - The amd64-linux build of gdbserver now supports debugging both
2263 32-bit and 64-bit programs.
2265 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2266 now support hardware watchpoints, and will use them automatically
2271 GDB now has support for scripting using Python. Whether this is
2272 available is determined at configure time.
2274 New GDB commands can now be written in Python.
2276 * Ada tasking support
2278 Ada tasks can now be inspected in GDB. The following commands have
2282 Print the list of Ada tasks.
2284 Print detailed information about task number N.
2286 Print the task number of the current task.
2288 Switch the context of debugging to task number N.
2290 * Support for user-defined prefixed commands. The "define" command can
2291 add new commands to existing prefixes, e.g. "target".
2293 * Multi-inferior, multi-process debugging.
2295 GDB now has generalized support for multi-inferior debugging. See
2296 "Debugging Multiple Inferiors" in the manual for more information.
2297 Although availability still depends on target support, the command
2298 set is more uniform now. The GNU/Linux specific multi-forks support
2299 has been migrated to this new framework. This implied some user
2300 visible changes; see "New commands" and also "Removed commands"
2303 * Target descriptions can now describe the target OS ABI. See the
2304 "Target Description Format" section in the user manual for more
2307 * Target descriptions can now describe "compatible" architectures
2308 to indicate that the target can execute applications for a different
2309 architecture in addition to those for the main target architecture.
2310 See the "Target Description Format" section in the user manual for
2313 * Multi-architecture debugging.
2315 GDB now includes general supports for debugging applications on
2316 hybrid systems that use more than one single processor architecture
2317 at the same time. Each such hybrid architecture still requires
2318 specific support to be added. The only hybrid architecture supported
2319 in this version of GDB is the Cell Broadband Engine.
2321 * GDB now supports integrated debugging of Cell/B.E. applications that
2322 use both the PPU and SPU architectures. To enable support for hybrid
2323 Cell/B.E. debugging, you need to configure GDB to support both the
2324 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2325 --enable-targets configure option.
2327 * Non-stop mode debugging.
2329 For some targets, GDB now supports an optional mode of operation in
2330 which you can examine stopped threads while other threads continue
2331 to execute freely. This is referred to as non-stop mode, with the
2332 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2333 section in the user manual for more information.
2335 To be able to support remote non-stop debugging, a remote stub needs
2336 to implement the non-stop mode remote protocol extensions, as
2337 described in the "Remote Non-Stop" section of the user manual. The
2338 GDB remote stub, gdbserver, has been adjusted to support these
2339 extensions on linux targets.
2341 * New commands (for set/show, see "New options" below)
2343 catch syscall [NAME(S) | NUMBER(S)]
2344 Catch system calls. Arguments, which should be names of system
2345 calls or their numbers, mean catch only those syscalls. Without
2346 arguments, every syscall will be caught. When the inferior issues
2347 any of the specified syscalls, GDB will stop and announce the system
2348 call, both when it is called and when its call returns. This
2349 feature is currently available with a native GDB running on the
2350 Linux Kernel, under the following architectures: x86, x86_64,
2351 PowerPC and PowerPC64.
2353 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2355 Search memory for a sequence of bytes.
2357 maint set python print-stack
2358 maint show python print-stack
2359 Show a stack trace when an error is encountered in a Python script.
2362 Invoke CODE by passing it to the Python interpreter.
2367 These allow macros to be defined, undefined, and listed
2371 Show operating system information about processes.
2374 List the inferiors currently under GDB's control.
2377 Switch focus to inferior number NUM.
2380 Detach from inferior number NUM.
2383 Kill inferior number NUM.
2387 set spu stop-on-load
2388 show spu stop-on-load
2389 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2391 set spu auto-flush-cache
2392 show spu auto-flush-cache
2393 Control whether to automatically flush the software-managed cache
2394 during Cell/B.E. debugging.
2396 set sh calling-convention
2397 show sh calling-convention
2398 Control the calling convention used when calling SH target functions.
2401 show debug timestamp
2402 Control display of timestamps with GDB debugging output.
2404 set disassemble-next-line
2405 show disassemble-next-line
2406 Control display of disassembled source lines or instructions when
2409 set remote noack-packet
2410 show remote noack-packet
2411 Set/show the use of remote protocol QStartNoAckMode packet. See above
2412 under "New remote packets."
2414 set remote query-attached-packet
2415 show remote query-attached-packet
2416 Control use of remote protocol `qAttached' (query-attached) packet.
2418 set remote read-siginfo-object
2419 show remote read-siginfo-object
2420 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2423 set remote write-siginfo-object
2424 show remote write-siginfo-object
2425 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2428 set remote reverse-continue
2429 show remote reverse-continue
2430 Control use of remote protocol 'bc' (reverse-continue) packet.
2432 set remote reverse-step
2433 show remote reverse-step
2434 Control use of remote protocol 'bs' (reverse-step) packet.
2436 set displaced-stepping
2437 show displaced-stepping
2438 Control displaced stepping mode. Displaced stepping is a way to
2439 single-step over breakpoints without removing them from the debuggee.
2440 Also known as "out-of-line single-stepping".
2443 show debug displaced
2444 Control display of debugging info for displaced stepping.
2446 maint set internal-error
2447 maint show internal-error
2448 Control what GDB does when an internal error is detected.
2450 maint set internal-warning
2451 maint show internal-warning
2452 Control what GDB does when an internal warning is detected.
2457 Use a wrapper program to launch programs for debugging.
2459 set multiple-symbols (all|ask|cancel)
2460 show multiple-symbols
2461 The value of this variable can be changed to adjust the debugger behavior
2462 when an expression or a breakpoint location contains an ambiguous symbol
2463 name (an overloaded function name, for instance).
2465 set breakpoint always-inserted
2466 show breakpoint always-inserted
2467 Keep breakpoints always inserted in the target, as opposed to inserting
2468 them when resuming the target, and removing them when the target stops.
2469 This option can improve debugger performance on slow remote targets.
2471 set arm fallback-mode (arm|thumb|auto)
2472 show arm fallback-mode
2473 set arm force-mode (arm|thumb|auto)
2475 These commands control how ARM GDB determines whether instructions
2476 are ARM or Thumb. The default for both settings is auto, which uses
2477 the current CPSR value for instructions without symbols; previous
2478 versions of GDB behaved as if "set arm fallback-mode arm".
2480 set disable-randomization
2481 show disable-randomization
2482 Standalone programs run with the virtual address space randomization enabled
2483 by default on some platforms. This option keeps the addresses stable across
2484 multiple debugging sessions.
2488 Control whether other threads are stopped or not when some thread hits
2493 Requests that asynchronous execution is enabled in the target, if available.
2494 In this case, it's possible to resume target in the background, and interact
2495 with GDB while the target is running. "show target-async" displays the
2496 current state of asynchronous execution of the target.
2498 set target-wide-charset
2499 show target-wide-charset
2500 The target-wide-charset is the name of the character set that GDB
2501 uses when printing characters whose type is wchar_t.
2503 set tcp auto-retry (on|off)
2505 set tcp connect-timeout
2506 show tcp connect-timeout
2507 These commands allow GDB to retry failed TCP connections to a remote stub
2508 with a specified timeout period; this is useful if the stub is launched
2509 in parallel with GDB but may not be ready to accept connections immediately.
2511 set libthread-db-search-path
2512 show libthread-db-search-path
2513 Control list of directories which GDB will search for appropriate
2516 set schedule-multiple (on|off)
2517 show schedule-multiple
2518 Allow GDB to resume all threads of all processes or only threads of
2519 the current process.
2523 Use more aggressive caching for accesses to the stack. This improves
2524 performance of remote debugging (particularly backtraces) without
2525 affecting correctness.
2527 set interactive-mode (on|off|auto)
2528 show interactive-mode
2529 Control whether GDB runs in interactive mode (on) or not (off).
2530 When in interactive mode, GDB waits for the user to answer all
2531 queries. Otherwise, GDB does not wait and assumes the default
2532 answer. When set to auto (the default), GDB determines which
2533 mode to use based on the stdin settings.
2538 For program forks, this is replaced by the new more generic `info
2539 inferiors' command. To list checkpoints, you can still use the
2540 `info checkpoints' command, which was an alias for the `info forks'
2544 Replaced by the new `inferior' command. To switch between
2545 checkpoints, you can still use the `restart' command, which was an
2546 alias for the `fork' command.
2549 This is removed, since some targets don't have a notion of
2550 processes. To switch between processes, you can still use the
2551 `inferior' command using GDB's own inferior number.
2554 For program forks, this is replaced by the new more generic `kill
2555 inferior' command. To delete a checkpoint, you can still use the
2556 `delete checkpoint' command, which was an alias for the `delete
2560 For program forks, this is replaced by the new more generic `detach
2561 inferior' command. To detach a checkpoint, you can still use the
2562 `detach checkpoint' command, which was an alias for the `detach
2565 * New native configurations
2567 x86/x86_64 Darwin i[34567]86-*-darwin*
2569 x86_64 MinGW x86_64-*-mingw*
2573 Lattice Mico32 lm32-*
2574 x86 DICOS i[34567]86-*-dicos*
2575 x86_64 DICOS x86_64-*-dicos*
2578 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2579 (mingw32ce) debugging.
2585 These commands were actually not implemented on any target.
2587 *** Changes in GDB 6.8
2589 * New native configurations
2591 NetBSD/hppa hppa*-*netbsd*
2592 Xtensa GNU/Linux xtensa*-*-linux*
2596 NetBSD/hppa hppa*-*-netbsd*
2597 Xtensa GNU/Lunux xtensa*-*-linux*
2599 * Change in command line behavior -- corefiles vs. process ids.
2601 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2602 attaching to process NUMBER fails, GDB no longer attempts to open a
2603 core file named NUMBER. Attaching to a program using the -c option
2604 is no longer supported. Instead, use the '-p' or '--pid' options.
2606 * GDB can now be built as a native debugger for debugging Windows x86
2607 (mingw32) Portable Executable (PE) programs.
2609 * Pending breakpoints no longer change their number when their address
2612 * GDB now supports breakpoints with multiple locations,
2613 including breakpoints on C++ constructors, inside C++ templates,
2614 and in inlined functions.
2616 * GDB's ability to debug optimized code has been improved. GDB more
2617 accurately identifies function bodies and lexical blocks that occupy
2618 more than one contiguous range of addresses.
2620 * Target descriptions can now describe registers for PowerPC.
2622 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2623 registers on PowerPC targets.
2625 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2626 targets even when the libthread_db library is not available.
2628 * The GDB remote stub, gdbserver, now supports the new file transfer
2629 commands (remote put, remote get, and remote delete).
2631 * The GDB remote stub, gdbserver, now supports run and attach in
2632 extended-remote mode.
2634 * hppa*64*-*-hpux11* target broken
2635 The debugger is unable to start a program and fails with the following
2636 error: "Error trying to get information about dynamic linker".
2637 The gdb-6.7 release is also affected.
2639 * GDB now supports the --enable-targets= configure option to allow
2640 building a single GDB executable that supports multiple remote
2641 target architectures.
2643 * GDB now supports debugging C and C++ programs which use the
2644 Decimal Floating Point extension. In addition, the PowerPC target
2645 now has a set of pseudo-registers to inspect decimal float values
2646 stored in two consecutive float registers.
2648 * The -break-insert MI command can optionally create pending
2651 * Improved support for debugging Ada
2652 Many improvements to the Ada language support have been made. These
2654 - Better support for Ada2005 interface types
2655 - Improved handling of arrays and slices in general
2656 - Better support for Taft-amendment types
2657 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2659 - Improved command completion in Ada
2662 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2667 set print frame-arguments (all|scalars|none)
2668 show print frame-arguments
2669 The value of this variable can be changed to control which argument
2670 values should be printed by the debugger when displaying a frame.
2675 Transfer files to and from a remote target, and delete remote files.
2682 Transfer files to and from a remote target, and delete remote files.
2684 * New remote packets
2691 Open, close, read, write, and delete files on the remote system.
2694 Attach to an existing process on the remote system, in extended-remote
2698 Run a new process on the remote system, in extended-remote mode.
2700 *** Changes in GDB 6.7
2702 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2703 bfd, libiberty and opcodes, as revealed by static analysis donated by
2704 Coverity, Inc. (http://scan.coverity.com).
2706 * When looking up multiply-defined global symbols, GDB will now prefer the
2707 symbol definition in the current shared library if it was built using the
2708 -Bsymbolic linker option.
2710 * When the Text User Interface (TUI) is not configured, GDB will now
2711 recognize the -tui command-line option and print a message that the TUI
2714 * The GDB remote stub, gdbserver, now has lower overhead for high
2715 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2717 * GDB for MIPS targets now autodetects whether a remote target provides
2718 32-bit or 64-bit register values.
2720 * Support for C++ member pointers has been improved.
2722 * GDB now understands XML target descriptions, which specify the
2723 target's overall architecture. GDB can read a description from
2724 a local file or over the remote serial protocol.
2726 * Vectors of single-byte data use a new integer type which is not
2727 automatically displayed as character or string data.
2729 * The /s format now works with the print command. It displays
2730 arrays of single-byte integers and pointers to single-byte integers
2733 * Target descriptions can now describe target-specific registers,
2734 for architectures which have implemented the support (currently
2735 only ARM, M68K, and MIPS).
2737 * GDB and the GDB remote stub, gdbserver, now support the XScale
2740 * The GDB remote stub, gdbserver, has been updated to support
2741 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2742 has been rewritten to use the standard GDB remote protocol.
2744 * GDB can now step into C++ functions which are called through thunks.
2746 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2748 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2749 layout. It also supports a TextSeg= and DataSeg= response when only
2750 segment base addresses (rather than offsets) are available.
2752 * The /i format now outputs any trailing branch delay slot instructions
2753 immediately following the last instruction within the count specified.
2755 * The GDB remote protocol "T" stop reply packet now supports a
2756 "library" response. Combined with the new "qXfer:libraries:read"
2757 packet, this response allows GDB to debug shared libraries on targets
2758 where the operating system manages the list of loaded libraries (e.g.
2759 Windows and SymbianOS).
2761 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2762 (DLLs) on Windows and Windows CE targets.
2764 * GDB now supports a faster verification that a .debug file matches its binary
2765 according to its build-id signature, if the signature is present.
2771 Enable or disable hardware flow control (RTS/CTS) on the serial port
2772 when debugging using remote targets.
2774 set mem inaccessible-by-default
2775 show mem inaccessible-by-default
2776 If the target supplies a memory map, for instance via the remote
2777 protocol's "qXfer:memory-map:read" packet, setting this variable
2778 prevents GDB from accessing memory outside the memory map. This
2779 is useful for targets with memory mapped registers or which react
2780 badly to accesses of unmapped address space.
2782 set breakpoint auto-hw
2783 show breakpoint auto-hw
2784 If the target supplies a memory map, for instance via the remote
2785 protocol's "qXfer:memory-map:read" packet, setting this variable
2786 lets GDB use hardware breakpoints automatically for memory regions
2787 where it can not use software breakpoints. This covers both the
2788 "break" command and internal breakpoints used for other commands
2789 including "next" and "finish".
2792 catch exception unhandled
2793 Stop the program execution when Ada exceptions are raised.
2796 Stop the program execution when an Ada assertion failed.
2800 Set an alternate system root for target files. This is a more
2801 general version of "set solib-absolute-prefix", which is now
2802 an alias to "set sysroot".
2805 Provide extended SPU facility status information. This set of
2806 commands is available only when debugging the Cell/B.E. SPU
2809 * New native configurations
2811 OpenBSD/sh sh*-*openbsd*
2814 unset tdesc filename
2816 Use the specified local file as an XML target description, and do
2817 not query the target for its built-in description.
2821 OpenBSD/sh sh*-*-openbsd*
2822 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2823 Toshiba Media Processor mep-elf
2825 * New remote packets
2828 Ignore the specified signals; pass them directly to the debugged program
2829 without stopping other threads or reporting them to GDB.
2831 qXfer:features:read:
2832 Read an XML target description from the target, which describes its
2837 Read or write contents of an spufs file on the target system. These
2838 packets are available only on the Cell/B.E. SPU architecture.
2840 qXfer:libraries:read:
2841 Report the loaded shared libraries. Combined with new "T" packet
2842 response, this packet allows GDB to debug shared libraries on
2843 targets where the operating system manages the list of loaded
2844 libraries (e.g. Windows and SymbianOS).
2848 Support for these obsolete configurations has been removed.
2856 i[34567]86-*-lynxos*
2857 i[34567]86-*-netware*
2858 i[34567]86-*-sco3.2v5*
2859 i[34567]86-*-sco3.2v4*
2861 i[34567]86-*-sysv4.2*
2864 i[34567]86-*-unixware2*
2865 i[34567]86-*-unixware*
2874 * Other removed features
2881 Various m68k-only ROM monitors.
2888 Various Renesas ROM monitors and debugging interfaces for SH and
2893 Support for a Macraigor serial interface to on-chip debugging.
2894 GDB does not directly support the newer parallel or USB
2899 A debug information format. The predecessor to DWARF 2 and
2900 DWARF 3, which are still supported.
2902 Support for the HP aCC compiler on HP-UX/PA-RISC
2904 SOM-encapsulated symbolic debugging information, automatic
2905 invocation of pxdb, and the aCC custom C++ ABI. This does not
2906 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2907 with aCC can still be debugged on an assembly level.
2909 MIPS ".pdr" sections
2911 A MIPS-specific format used to describe stack frame layout
2912 in debugging information.
2916 GDB could work with an older version of Guile to debug
2917 the interpreter and Scheme programs running in it.
2919 set mips stack-arg-size
2920 set mips saved-gpreg-size
2922 Use "set mips abi" to control parameter passing for MIPS.
2924 *** Changes in GDB 6.6
2929 Cell Broadband Engine SPU spu-elf
2931 * GDB can now be configured as a cross-debugger targeting native Windows
2932 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2933 running on a Windows system over TCP/IP to debug Windows programs.
2935 * The GDB remote stub, gdbserver, has been updated to support Windows and
2936 Cygwin debugging. Both single-threaded and multi-threaded programs are
2939 * The "set trust-readonly-sections" command works again. This command was
2940 broken in GDB 6.3, 6.4, and 6.5.
2942 * The "load" command now supports writing to flash memory, if the remote
2943 stub provides the required support.
2945 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2946 longer requires symbolic debug information (e.g. DWARF-2).
2951 unset substitute-path
2952 show substitute-path
2953 Manage a list of substitution rules that GDB uses to rewrite the name
2954 of the directories where the sources are located. This can be useful
2955 for instance when the sources were moved to a different location
2956 between compilation and debugging.
2960 Print each CLI command as it is executed. Each command is prefixed with
2961 a number of `+' symbols representing the nesting depth.
2962 The source command now has a `-v' option to enable the same feature.
2966 The ARM Demon monitor support (RDP protocol, "target rdp").
2968 Kernel Object Display, an embedded debugging feature which only worked with
2969 an obsolete version of Cisco IOS.
2971 The 'set download-write-size' and 'show download-write-size' commands.
2973 * New remote packets
2976 Tell a stub about GDB client features, and request remote target features.
2977 The first feature implemented is PacketSize, which allows the target to
2978 specify the size of packets it can handle - to minimize the number of
2979 packets required and improve performance when connected to a remote
2983 Fetch an OS auxilliary vector from the remote stub. This packet is a
2984 more efficient replacement for qPart:auxv:read.
2986 qXfer:memory-map:read:
2987 Fetch a memory map from the remote stub, including information about
2988 RAM, ROM, and flash memory devices.
2993 Erase and program a flash memory device.
2995 * Removed remote packets
2998 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2999 used it, and only gdbserver implemented it.
3001 *** Changes in GDB 6.5
3005 Renesas M32C/M16C m32c-elf
3007 Morpho Technologies ms1 ms1-elf
3011 init-if-undefined Initialize a convenience variable, but
3012 only if it doesn't already have a value.
3014 The following commands are presently only implemented for native GNU/Linux:
3016 checkpoint Save a snapshot of the program state.
3018 restart <n> Return the program state to a
3019 previously saved state.
3021 info checkpoints List currently saved checkpoints.
3023 delete-checkpoint <n> Delete a previously saved checkpoint.
3025 set|show detach-on-fork Tell gdb whether to detach from a newly
3026 forked process, or to keep debugging it.
3028 info forks List forks of the user program that
3029 are available to be debugged.
3031 fork <n> Switch to debugging one of several
3032 forks of the user program that are
3033 available to be debugged.
3035 delete-fork <n> Delete a fork from the list of forks
3036 that are available to be debugged (and
3037 kill the forked process).
3039 detach-fork <n> Delete a fork from the list of forks
3040 that are available to be debugged (and
3041 allow the process to continue).
3045 Morpho Technologies ms2 ms1-elf
3047 * Improved Windows host support
3049 GDB now builds as a cross debugger hosted on i686-mingw32, including
3050 native console support, and remote communications using either
3051 network sockets or serial ports.
3053 * Improved Modula-2 language support
3055 GDB can now print most types in the Modula-2 syntax. This includes:
3056 basic types, set types, record types, enumerated types, range types,
3057 pointer types and ARRAY types. Procedure var parameters are correctly
3058 printed and hexadecimal addresses and character constants are also
3059 written in the Modula-2 syntax. Best results can be obtained by using
3060 GNU Modula-2 together with the -gdwarf-2 command line option.
3064 The ARM rdi-share module.
3066 The Netware NLM debug server.
3068 *** Changes in GDB 6.4
3070 * New native configurations
3072 OpenBSD/arm arm*-*-openbsd*
3073 OpenBSD/mips64 mips64-*-openbsd*
3077 Morpho Technologies ms1 ms1-elf
3079 * New command line options
3081 --batch-silent As for --batch, but totally silent.
3082 --return-child-result The debugger will exist with the same value
3083 the child (debugged) program exited with.
3084 --eval-command COMMAND, -ex COMMAND
3085 Execute a single GDB CLI command. This may be
3086 specified multiple times and in conjunction
3087 with the --command (-x) option.
3089 * Deprecated commands removed
3091 The following commands, that were deprecated in 2000, have been
3095 set|show arm disassembly-flavor set|show arm disassembler
3096 othernames set arm disassembler
3097 set|show remotedebug set|show debug remote
3098 set|show archdebug set|show debug arch
3099 set|show eventdebug set|show debug event
3102 * New BSD user-level threads support
3104 It is now possible to debug programs using the user-level threads
3105 library on OpenBSD and FreeBSD. Currently supported (target)
3108 FreeBSD/amd64 x86_64-*-freebsd*
3109 FreeBSD/i386 i386-*-freebsd*
3110 OpenBSD/i386 i386-*-openbsd*
3112 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3113 are not yet supported.
3115 * New support for Matsushita MN10300 w/sim added
3116 (Work in progress). mn10300-elf.
3118 * REMOVED configurations and files
3120 VxWorks and the XDR protocol *-*-vxworks
3121 Motorola MCORE mcore-*-*
3122 National Semiconductor NS32000 ns32k-*-*
3124 * New "set print array-indexes" command
3126 After turning this setting "on", GDB prints the index of each element
3127 when displaying arrays. The default is "off" to preserve the previous
3130 * VAX floating point support
3132 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3134 * User-defined command support
3136 In addition to using $arg0..$arg9 for argument passing, it is now possible
3137 to use $argc to determine now many arguments have been passed. See the
3138 section on user-defined commands in the user manual for more information.
3140 *** Changes in GDB 6.3:
3142 * New command line option
3144 GDB now accepts -l followed by a number to set the timeout for remote
3147 * GDB works with GCC -feliminate-dwarf2-dups
3149 GDB now supports a more compact representation of DWARF-2 debug
3150 information using DW_FORM_ref_addr references. These are produced
3151 by GCC with the option -feliminate-dwarf2-dups and also by some
3152 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3153 to use -feliminate-dwarf2-dups.
3155 * Internationalization
3157 When supported by the host system, GDB will be built with
3158 internationalization (libintl). The task of marking up the sources is
3159 continued, we're looking forward to our first translation.
3163 Initial support for debugging programs compiled with the GNAT
3164 implementation of the Ada programming language has been integrated
3165 into GDB. In this release, support is limited to expression evaluation.
3167 * New native configurations
3169 GNU/Linux/m32r m32r-*-linux-gnu
3173 GDB's remote protocol now includes support for the 'p' packet. This
3174 packet is used to fetch individual registers from a remote inferior.
3176 * END-OF-LIFE registers[] compatibility module
3178 GDB's internal register infrastructure has been completely rewritten.
3179 The new infrastructure making possible the implementation of key new
3180 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3183 GDB 6.3 will be the last release to include the the registers[]
3184 compatibility module that allowed out-of-date configurations to
3185 continue to work. This change directly impacts the following
3195 powerpc bdm protocol
3197 Unless there is activity to revive these configurations, they will be
3198 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3200 * OBSOLETE configurations and files
3202 Configurations that have been declared obsolete in this release have
3203 been commented out. Unless there is activity to revive these
3204 configurations, the next release of GDB will have their sources
3205 permanently REMOVED.
3214 *** Changes in GDB 6.2.1:
3216 * MIPS `break main; run' gave an heuristic-fence-post warning
3218 When attempting to run even a simple program, a warning about
3219 heuristic-fence-post being hit would be reported. This problem has
3222 * MIPS IRIX 'long double' crashed GDB
3224 When examining a long double variable, GDB would get a segmentation
3225 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3226 IRIX long double values).
3230 A bug in the VAX stack code was causing problems with the "next"
3231 command. This problem has been fixed.
3233 *** Changes in GDB 6.2:
3235 * Fix for ``many threads''
3237 On GNU/Linux systems that use the NPTL threads library, a program
3238 rapidly creating and deleting threads would confuse GDB leading to the
3241 ptrace: No such process.
3242 thread_db_get_info: cannot get thread info: generic error
3244 This problem has been fixed.
3246 * "-async" and "-noasync" options removed.
3248 Support for the broken "-noasync" option has been removed (it caused
3251 * New ``start'' command.
3253 This command runs the program until the begining of the main procedure.
3255 * New BSD Kernel Data Access Library (libkvm) interface
3257 Using ``target kvm'' it is now possible to debug kernel core dumps and
3258 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3259 platforms. Currently supported (native-only) configurations are:
3261 FreeBSD/amd64 x86_64-*-freebsd*
3262 FreeBSD/i386 i?86-*-freebsd*
3263 NetBSD/i386 i?86-*-netbsd*
3264 NetBSD/m68k m68*-*-netbsd*
3265 NetBSD/sparc sparc-*-netbsd*
3266 OpenBSD/amd64 x86_64-*-openbsd*
3267 OpenBSD/i386 i?86-*-openbsd*
3268 OpenBSD/m68k m68*-openbsd*
3269 OpenBSD/sparc sparc-*-openbsd*
3271 * Signal trampoline code overhauled
3273 Many generic problems with GDB's signal handling code have been fixed.
3274 These include: backtraces through non-contiguous stacks; recognition
3275 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3276 call; backtrace through a signal trampoline; step into and out of
3277 signal handlers; and single-stepping in the signal trampoline.
3279 Please note that kernel bugs are a limiting factor here. These
3280 features have been shown to work on an s390 GNU/Linux system that
3281 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3283 * Cygwin support for DWARF 2 added.
3285 * New native configurations
3287 GNU/Linux/hppa hppa*-*-linux*
3288 OpenBSD/hppa hppa*-*-openbsd*
3289 OpenBSD/m68k m68*-*-openbsd*
3290 OpenBSD/m88k m88*-*-openbsd*
3291 OpenBSD/powerpc powerpc-*-openbsd*
3292 NetBSD/vax vax-*-netbsd*
3293 OpenBSD/vax vax-*-openbsd*
3295 * END-OF-LIFE frame compatibility module
3297 GDB's internal frame infrastructure has been completely rewritten.
3298 The new infrastructure making it possible to support key new features
3299 including DWARF 2 Call Frame Information. To aid in the task of
3300 migrating old configurations to this new infrastructure, a
3301 compatibility module, that allowed old configurations to continue to
3302 work, was also included.
3304 GDB 6.2 will be the last release to include this frame compatibility
3305 module. This change directly impacts the following configurations:
3315 Unless there is activity to revive these configurations, they will be
3316 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3318 * REMOVED configurations and files
3320 Sun 3, running SunOS 3 m68*-*-sunos3*
3321 Sun 3, running SunOS 4 m68*-*-sunos4*
3322 Sun 2, running SunOS 3 m68000-*-sunos3*
3323 Sun 2, running SunOS 4 m68000-*-sunos4*
3324 Motorola 680x0 running LynxOS m68*-*-lynxos*
3325 AT&T 3b1/Unix pc m68*-att-*
3326 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3327 decstation mips-dec-* mips-little-*
3328 riscos mips-*-riscos* mips-*-sysv*
3329 sonymips mips-sony-*
3330 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3332 *** Changes in GDB 6.1.1:
3334 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3336 The TUI (Text-mode User Interface) is now built as part of a default
3337 GDB configuration. It is enabled by either selecting the TUI with the
3338 command line option "-i=tui" or by running the separate "gdbtui"
3339 program. For more information on the TUI, see the manual "Debugging
3342 * Pending breakpoint support (also included in GDB 6.1)
3344 Support has been added to allow you to specify breakpoints in shared
3345 libraries that have not yet been loaded. If a breakpoint location
3346 cannot be found, and the "breakpoint pending" option is set to auto,
3347 GDB queries you if you wish to make the breakpoint pending on a future
3348 shared-library load. If and when GDB resolves the breakpoint symbol,
3349 the pending breakpoint is removed as one or more regular breakpoints
3352 Pending breakpoints are very useful for GCJ Java debugging.
3354 * Fixed ISO-C build problems
3356 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3357 non ISO-C code that stopped them being built using a more strict ISO-C
3358 compiler (e.g., IBM's C compiler).
3360 * Fixed build problem on IRIX 5
3362 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3363 wasn't able to compile compile on an IRIX 5 system.
3365 * Added execute permission to gdb/gdbserver/configure
3367 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3368 permission. This bug would cause configure to fail on a number of
3369 systems (Solaris, IRIX). Ref: server/519.
3371 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3373 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3374 has been updated to use constant array sizes.
3376 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3378 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3379 its generated DWARF Call Frame Info. This encoding was causing GDB to
3380 panic, that panic has been fixed. Ref: gdb/1628.
3382 * Fixed a problem when examining parameters in shared library code.
3384 When examining parameters in optimized shared library code generated
3385 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3386 not available''. GDB now correctly displays the variable's value.
3388 *** Changes in GDB 6.1:
3390 * Removed --with-mmalloc
3392 Support for the mmalloc memory manager has been removed, as it
3393 conflicted with the internal gdb byte cache.
3395 * Changes in AMD64 configurations
3397 The AMD64 target now includes the %cs and %ss registers. As a result
3398 the AMD64 remote protocol has changed; this affects the floating-point
3399 and SSE registers. If you rely on those registers for your debugging,
3400 you should upgrade gdbserver on the remote side.
3402 * Revised SPARC target
3404 The SPARC target has been completely revised, incorporating the
3405 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3406 support for LynxOS and SunOS 4 has been dropped. Calling functions
3407 from within GDB on operating systems with a non-executable stack
3408 (Solaris, OpenBSD) now works.
3412 GDB has a new C++ demangler which does a better job on the mangled
3413 names generated by current versions of g++. It also runs faster, so
3414 with this and other changes gdb should now start faster on large C++
3417 * DWARF 2 Location Expressions
3419 GDB support for location expressions has been extended to support function
3420 arguments and frame bases. Older versions of GDB could crash when they
3423 * C++ nested types and namespaces
3425 GDB's support for nested types and namespaces in C++ has been
3426 improved, especially if you use the DWARF 2 debugging format. (This
3427 is the default for recent versions of GCC on most platforms.)
3428 Specifically, if you have a class "Inner" defined within a class or
3429 namespace "Outer", then GDB realizes that the class's name is
3430 "Outer::Inner", not simply "Inner". This should greatly reduce the
3431 frequency of complaints about not finding RTTI symbols. In addition,
3432 if you are stopped at inside of a function defined within a namespace,
3433 GDB modifies its name lookup accordingly.
3435 * New native configurations
3437 NetBSD/amd64 x86_64-*-netbsd*
3438 OpenBSD/amd64 x86_64-*-openbsd*
3439 OpenBSD/alpha alpha*-*-openbsd*
3440 OpenBSD/sparc sparc-*-openbsd*
3441 OpenBSD/sparc64 sparc64-*-openbsd*
3443 * New debugging protocols
3445 M32R with SDI protocol m32r-*-elf*
3447 * "set prompt-escape-char" command deleted.
3449 The command "set prompt-escape-char" has been deleted. This command,
3450 and its very obscure effet on GDB's prompt, was never documented,
3451 tested, nor mentioned in the NEWS file.
3453 * OBSOLETE configurations and files
3455 Configurations that have been declared obsolete in this release have
3456 been commented out. Unless there is activity to revive these
3457 configurations, the next release of GDB will have their sources
3458 permanently REMOVED.
3460 Sun 3, running SunOS 3 m68*-*-sunos3*
3461 Sun 3, running SunOS 4 m68*-*-sunos4*
3462 Sun 2, running SunOS 3 m68000-*-sunos3*
3463 Sun 2, running SunOS 4 m68000-*-sunos4*
3464 Motorola 680x0 running LynxOS m68*-*-lynxos*
3465 AT&T 3b1/Unix pc m68*-att-*
3466 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3467 decstation mips-dec-* mips-little-*
3468 riscos mips-*-riscos* mips-*-sysv*
3469 sonymips mips-sony-*
3470 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3472 * REMOVED configurations and files
3474 SGI Irix-4.x mips-sgi-irix4 or iris4
3475 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3476 Z8000 simulator z8k-zilog-none or z8ksim
3477 Matsushita MN10200 w/simulator mn10200-*-*
3478 H8/500 simulator h8500-hitachi-hms or h8500hms
3479 HP/PA running BSD hppa*-*-bsd*
3480 HP/PA running OSF/1 hppa*-*-osf*
3481 HP/PA Pro target hppa*-*-pro*
3482 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3483 386BSD i[3456]86-*-bsd*
3484 Sequent family i[3456]86-sequent-sysv4*
3485 i[3456]86-sequent-sysv*
3486 i[3456]86-sequent-bsd*
3487 SPARC running LynxOS sparc-*-lynxos*
3488 SPARC running SunOS 4 sparc-*-sunos4*
3489 Tsqware Sparclet sparclet-*-*
3490 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3492 *** Changes in GDB 6.0:
3496 Support for debugging the Objective-C programming language has been
3497 integrated into GDB.
3499 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3501 DWARF 2's Call Frame Information makes available compiler generated
3502 information that more exactly describes the program's run-time stack.
3503 By using this information, GDB is able to provide more robust stack
3506 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3507 have been updated to use a new backtrace mechanism which includes
3508 DWARF 2 CFI support.
3512 GDB's remote protocol has been extended to include support for hosted
3513 file I/O (where the remote target uses GDB's file system). See GDB's
3514 remote protocol documentation for details.
3516 * All targets using the new architecture framework.
3518 All of GDB's targets have been updated to use the new internal
3519 architecture framework. The way is now open for future GDB releases
3520 to include cross-architecture native debugging support (i386 on amd64,
3523 * GNU/Linux's Thread Local Storage (TLS)
3525 GDB now includes support for for the GNU/Linux implementation of
3526 per-thread variables.
3528 * GNU/Linux's Native POSIX Thread Library (NPTL)
3530 GDB's thread code has been updated to work with either the new
3531 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3533 * Separate debug info.
3535 GDB, in conjunction with BINUTILS, now supports a mechanism for
3536 automatically loading debug information from a separate file. Instead
3537 of shipping full debug and non-debug versions of system libraries,
3538 system integrators can now instead ship just the stripped libraries
3539 and optional debug files.
3541 * DWARF 2 Location Expressions
3543 DWARF 2 Location Expressions allow the compiler to more completely
3544 describe the location of variables (even in optimized code) to the
3547 GDB now includes preliminary support for location expressions (support
3548 for DW_OP_piece is still missing).
3552 A number of long standing bugs that caused GDB to die while starting a
3553 Java application have been fixed. GDB's Java support is now
3554 considered "useable".
3556 * GNU/Linux support for fork, vfork, and exec.
3558 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3559 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3562 * GDB supports logging output to a file
3564 There are two new commands, "set logging" and "show logging", which can be
3565 used to capture GDB's output to a file.
3567 * The meaning of "detach" has changed for gdbserver
3569 The "detach" command will now resume the application, as documented. To
3570 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3573 * d10v, m68hc11 `regs' command deprecated
3575 The `info registers' command has been updated so that it displays the
3576 registers using a format identical to the old `regs' command.
3580 A new command, "maint set profile on/off", has been added. This command can
3581 be used to enable or disable profiling while running GDB, to profile a
3582 session or a set of commands. In addition there is a new configure switch,
3583 "--enable-profiling", which will cause GDB to be compiled with profiling
3584 data, for more informative profiling results.
3586 * Default MI syntax changed to "mi2".
3588 The default MI (machine interface) syntax, enabled by the command line
3589 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3590 "mi1", can be enabled by specifying the option "-i=mi1".
3592 Support for the original "mi0" syntax (included in GDB 5.0) has been
3595 Fix for gdb/192: removed extraneous space when displaying frame level.
3596 Fix for gdb/672: update changelist is now output in mi list format.
3597 Fix for gdb/702: a -var-assign that updates the value now shows up
3598 in a subsequent -var-update.
3600 * New native configurations.
3602 FreeBSD/amd64 x86_64-*-freebsd*
3604 * Multi-arched targets.
3606 HP/PA HPUX11 hppa*-*-hpux*
3607 Renesas M32R/D w/simulator m32r-*-elf*
3609 * OBSOLETE configurations and files
3611 Configurations that have been declared obsolete in this release have
3612 been commented out. Unless there is activity to revive these
3613 configurations, the next release of GDB will have their sources
3614 permanently REMOVED.
3616 Z8000 simulator z8k-zilog-none or z8ksim
3617 Matsushita MN10200 w/simulator mn10200-*-*
3618 H8/500 simulator h8500-hitachi-hms or h8500hms
3619 HP/PA running BSD hppa*-*-bsd*
3620 HP/PA running OSF/1 hppa*-*-osf*
3621 HP/PA Pro target hppa*-*-pro*
3622 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3623 Sequent family i[3456]86-sequent-sysv4*
3624 i[3456]86-sequent-sysv*
3625 i[3456]86-sequent-bsd*
3626 Tsqware Sparclet sparclet-*-*
3627 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3629 * REMOVED configurations and files
3632 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3633 IBM AIX PS/2 i[3456]86-*-aix
3634 i386 running Mach 3.0 i[3456]86-*-mach3*
3635 i386 running Mach i[3456]86-*-mach*
3636 i386 running OSF/1 i[3456]86-*osf1mk*
3637 HP/Apollo 68k Family m68*-apollo*-sysv*,
3639 m68*-hp-bsd*, m68*-hp-hpux*
3640 Argonaut Risc Chip (ARC) arc-*-*
3641 Mitsubishi D30V d30v-*-*
3642 Fujitsu FR30 fr30-*-elf*
3643 OS/9000 i[34]86-*-os9k
3644 I960 with MON960 i960-*-coff
3646 * MIPS $fp behavior changed
3648 The convenience variable $fp, for the MIPS, now consistently returns
3649 the address of the current frame's base. Previously, depending on the
3650 context, $fp could refer to either $sp or the current frame's base
3651 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3652 The GNU Source-Level Debugger''.
3654 *** Changes in GDB 5.3:
3656 * GNU/Linux shared library multi-threaded performance improved.
3658 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3659 `/proc', in preference to `ptrace' for memory reads. This may result
3660 in an improvement in the start-up time of multi-threaded, shared
3661 library applications when run under GDB. One GDB user writes: ``loads
3662 shared libs like mad''.
3664 * ``gdbserver'' now supports multi-threaded applications on some targets
3666 Support for debugging multi-threaded applications which use
3667 the GNU/Linux LinuxThreads package has been added for
3668 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3669 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3671 * GDB now supports C/C++ preprocessor macros.
3673 GDB now expands preprocessor macro invocations in C/C++ expressions,
3674 and provides various commands for showing macro definitions and how
3677 The new command `macro expand EXPRESSION' expands any macro
3678 invocations in expression, and shows the result.
3680 The new command `show macro MACRO-NAME' shows the definition of the
3681 macro named MACRO-NAME, and where it was defined.
3683 Most compilers don't include information about macros in the debugging
3684 information by default. In GCC 3.1, for example, you need to compile
3685 your program with the options `-gdwarf-2 -g3'. If the macro
3686 information is present in the executable, GDB will read it.
3688 * Multi-arched targets.
3690 DEC Alpha (partial) alpha*-*-*
3691 DEC VAX (partial) vax-*-*
3693 National Semiconductor NS32000 (partial) ns32k-*-*
3694 Motorola 68000 (partial) m68k-*-*
3695 Motorola MCORE mcore-*-*
3699 Fujitsu FRV architecture added by Red Hat frv*-*-*
3702 * New native configurations
3704 Alpha NetBSD alpha*-*-netbsd*
3705 SH NetBSD sh*-*-netbsdelf*
3706 MIPS NetBSD mips*-*-netbsd*
3707 UltraSPARC NetBSD sparc64-*-netbsd*
3709 * OBSOLETE configurations and files
3711 Configurations that have been declared obsolete in this release have
3712 been commented out. Unless there is activity to revive these
3713 configurations, the next release of GDB will have their sources
3714 permanently REMOVED.
3716 Mitsubishi D30V d30v-*-*
3717 OS/9000 i[34]86-*-os9k
3718 IBM AIX PS/2 i[3456]86-*-aix
3719 Fujitsu FR30 fr30-*-elf*
3720 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3721 Argonaut Risc Chip (ARC) arc-*-*
3722 i386 running Mach 3.0 i[3456]86-*-mach3*
3723 i386 running Mach i[3456]86-*-mach*
3724 i386 running OSF/1 i[3456]86-*osf1mk*
3725 HP/Apollo 68k Family m68*-apollo*-sysv*,
3727 m68*-hp-bsd*, m68*-hp-hpux*
3728 I960 with MON960 i960-*-coff
3730 * OBSOLETE languages
3732 CHILL, a Pascal like language used by telecommunications companies.
3734 * REMOVED configurations and files
3736 AMD 29k family via UDI a29k-amd-udi, udi29k
3737 A29K VxWorks a29k-*-vxworks
3738 AMD 29000 embedded, using EBMON a29k-none-none
3739 AMD 29000 embedded with COFF a29k-none-coff
3740 AMD 29000 embedded with a.out a29k-none-aout
3742 testsuite/gdb.hp/gdb.threads-hp/ directory
3744 * New command "set max-user-call-depth <nnn>"
3746 This command allows the user to limit the call depth of user-defined
3747 commands. The default is 1024.
3749 * Changes in FreeBSD/i386 native debugging.
3751 Support for the "generate-core-file" has been added.
3753 * New commands "dump", "append", and "restore".
3755 These commands allow data to be copied from target memory
3756 to a bfd-format or binary file (dump and append), and back
3757 from a file into memory (restore).
3759 * Improved "next/step" support on multi-processor Alpha Tru64.
3761 The previous single-step mechanism could cause unpredictable problems,
3762 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3763 of a software single-step mechanism prevents this.
3765 *** Changes in GDB 5.2.1:
3773 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3774 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3775 Fix, by Joel Brobecker imported from mainline.
3777 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3778 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3779 Fix, by Fred Fish, imported from mainline.
3781 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3782 Surprisingly enough, it works now.
3783 By Michal Ludvig, imported from mainline.
3785 i386 hardware watchpoint support:
3786 avoid misses on second run for some targets.
3787 By Pierre Muller, imported from mainline.
3789 *** Changes in GDB 5.2:
3791 * New command "set trust-readonly-sections on[off]".
3793 This command is a hint that tells gdb that read-only sections
3794 really are read-only (ie. that their contents will not change).
3795 In this mode, gdb will go to the object file rather than the
3796 target to read memory from read-only sections (such as ".text").
3797 This can be a significant performance improvement on some
3798 (notably embedded) targets.
3800 * New command "generate-core-file" (or "gcore").
3802 This new gdb command allows the user to drop a core file of the child
3803 process state at any time. So far it's been implemented only for
3804 GNU/Linux and Solaris, but should be relatively easily ported to other
3805 hosts. Argument is core file name (defaults to core.<pid>).
3807 * New command line option
3809 GDB now accepts --pid or -p followed by a process id.
3811 * Change in command line behavior -- corefiles vs. process ids.
3813 There is a subtle behavior in the way in which GDB handles
3814 command line arguments. The first non-flag argument is always
3815 a program to debug, but the second non-flag argument may either
3816 be a corefile or a process id. Previously, GDB would attempt to
3817 open the second argument as a corefile, and if that failed, would
3818 issue a superfluous error message and then attempt to attach it as
3819 a process. Now, if the second argument begins with a non-digit,
3820 it will be treated as a corefile. If it begins with a digit,
3821 GDB will attempt to attach it as a process, and if no such process
3822 is found, will then attempt to open it as a corefile.
3824 * Changes in ARM configurations.
3826 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3827 configuration is fully multi-arch.
3829 * New native configurations
3831 ARM NetBSD arm*-*-netbsd*
3832 x86 OpenBSD i[3456]86-*-openbsd*
3833 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3834 Sparc64 running FreeBSD sparc64-*-freebsd*
3838 Sanyo XStormy16 xstormy16-elf
3840 * OBSOLETE configurations and files
3842 Configurations that have been declared obsolete in this release have
3843 been commented out. Unless there is activity to revive these
3844 configurations, the next release of GDB will have their sources
3845 permanently REMOVED.
3847 AMD 29k family via UDI a29k-amd-udi, udi29k
3848 A29K VxWorks a29k-*-vxworks
3849 AMD 29000 embedded, using EBMON a29k-none-none
3850 AMD 29000 embedded with COFF a29k-none-coff
3851 AMD 29000 embedded with a.out a29k-none-aout
3853 testsuite/gdb.hp/gdb.threads-hp/ directory
3855 * REMOVED configurations and files
3857 TI TMS320C80 tic80-*-*
3859 PowerPC Solaris powerpcle-*-solaris*
3860 PowerPC Windows NT powerpcle-*-cygwin32
3861 PowerPC Netware powerpc-*-netware*
3862 Harris/CXUX m88k m88*-harris-cxux*
3863 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3864 ns32k-utek-sysv* ns32k-utek-*
3865 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3866 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3867 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3868 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3869 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3871 * Changes to command line processing
3873 The new `--args' feature can be used to specify command-line arguments
3874 for the inferior from gdb's command line.
3876 * Changes to key bindings
3878 There is a new `operate-and-get-next' function bound to `C-o'.
3880 *** Changes in GDB 5.1.1
3882 Fix compile problem on DJGPP.
3884 Fix a problem with floating-point registers on the i386 being
3887 Fix to stop GDB crashing on .debug_str debug info.
3889 Numerous documentation fixes.
3891 Numerous testsuite fixes.
3893 *** Changes in GDB 5.1:
3895 * New native configurations
3897 Alpha FreeBSD alpha*-*-freebsd*
3898 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3899 MIPS GNU/Linux mips*-*-linux*
3900 MIPS SGI Irix 6.x mips*-sgi-irix6*
3901 ia64 AIX ia64-*-aix*
3902 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3906 Motorola 68HC11 and 68HC12 m68hc11-elf
3908 UltraSparc running GNU/Linux sparc64-*-linux*
3910 * OBSOLETE configurations and files
3912 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3913 Harris/CXUX m88k m88*-harris-cxux*
3914 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3915 ns32k-utek-sysv* ns32k-utek-*
3916 TI TMS320C80 tic80-*-*
3918 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3919 PowerPC Solaris powerpcle-*-solaris*
3920 PowerPC Windows NT powerpcle-*-cygwin32
3921 PowerPC Netware powerpc-*-netware*
3922 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3923 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3924 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3925 Apple Macintosh (MPW) host N/A
3927 stuff.c (Program to stuff files into a specially prepared space in kdb)
3928 kdb-start.c (Main loop for the standalone kernel debugger)
3930 Configurations that have been declared obsolete in this release have
3931 been commented out. Unless there is activity to revive these
3932 configurations, the next release of GDB will have their sources
3933 permanently REMOVED.
3935 * REMOVED configurations and files
3937 Altos 3068 m68*-altos-*
3938 Convex c1-*-*, c2-*-*
3940 ARM RISCix arm-*-* (as host)
3944 * GDB has been converted to ISO C.
3946 GDB's source code has been converted to ISO C. In particular, the
3947 sources are fully protoized, and rely on standard headers being
3952 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3954 * The MI enabled by default.
3956 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3957 revised and enabled by default. Packages which use GDB as a debugging
3958 engine behind a UI or another front end are encouraged to switch to
3959 using the GDB/MI interface, instead of the old annotations interface
3960 which is now deprecated.
3962 * Support for debugging Pascal programs.
3964 GDB now includes support for debugging Pascal programs. The following
3965 main features are supported:
3967 - Pascal-specific data types such as sets;
3969 - automatic recognition of Pascal sources based on file-name
3972 - Pascal-style display of data types, variables, and functions;
3974 - a Pascal expression parser.
3976 However, some important features are not yet supported.
3978 - Pascal string operations are not supported at all;
3980 - there are some problems with boolean types;
3982 - Pascal type hexadecimal constants are not supported
3983 because they conflict with the internal variables format;
3985 - support for Pascal objects and classes is not full yet;
3987 - unlike Pascal, GDB is case-sensitive for symbol names.
3989 * Changes in completion.
3991 Commands such as `shell', `run' and `set args', which pass arguments
3992 to inferior programs, now complete on file names, similar to what
3993 users expect at the shell prompt.
3995 Commands which accept locations, such as `disassemble', `print',
3996 `breakpoint', `until', etc. now complete on filenames as well as
3997 program symbols. Thus, if you type "break foob TAB", and the source
3998 files linked into the programs include `foobar.c', that file name will
3999 be one of the candidates for completion. However, file names are not
4000 considered for completion after you typed a colon that delimits a file
4001 name from a name of a function in that file, as in "break foo.c:bar".
4003 `set demangle-style' completes on available demangling styles.
4005 * New platform-independent commands:
4007 It is now possible to define a post-hook for a command as well as a
4008 hook that runs before the command. For more details, see the
4009 documentation of `hookpost' in the GDB manual.
4011 * Changes in GNU/Linux native debugging.
4013 Support for debugging multi-threaded programs has been completely
4014 revised for all platforms except m68k and sparc. You can now debug as
4015 many threads as your system allows you to have.
4017 Attach/detach is supported for multi-threaded programs.
4019 Support for SSE registers was added for x86. This doesn't work for
4020 multi-threaded programs though.
4022 * Changes in MIPS configurations.
4024 Multi-arch support is enabled for all MIPS configurations.
4026 GDB can now be built as native debugger on SGI Irix 6.x systems for
4027 debugging n32 executables. (Debugging 64-bit executables is not yet
4030 * Unified support for hardware watchpoints in all x86 configurations.
4032 Most (if not all) native x86 configurations support hardware-assisted
4033 breakpoints and watchpoints in a unified manner. This support
4034 implements debug register sharing between watchpoints, which allows to
4035 put a virtually infinite number of watchpoints on the same address,
4036 and also supports watching regions up to 16 bytes with several debug
4039 The new maintenance command `maintenance show-debug-regs' toggles
4040 debugging print-outs in functions that insert, remove, and test
4041 watchpoints and hardware breakpoints.
4043 * Changes in the DJGPP native configuration.
4045 New command ``info dos sysinfo'' displays assorted information about
4046 the CPU, OS, memory, and DPMI server.
4048 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4049 display information about segment descriptors stored in GDT, LDT, and
4052 New commands ``info dos pde'' and ``info dos pte'' display entries
4053 from Page Directory and Page Tables (for now works with CWSDPMI only).
4054 New command ``info dos address-pte'' displays the Page Table entry for
4055 a given linear address.
4057 GDB can now pass command lines longer than 126 characters to the
4058 program being debugged (requires an update to the libdbg.a library
4059 which is part of the DJGPP development kit).
4061 DWARF2 debug info is now supported.
4063 It is now possible to `step' and `next' through calls to `longjmp'.
4065 * Changes in documentation.
4067 All GDB documentation was converted to GFDL, the GNU Free
4068 Documentation License.
4070 Tracepoints-related commands are now fully documented in the GDB
4073 TUI, the Text-mode User Interface, is now documented in the manual.
4075 Tracepoints-related commands are now fully documented in the GDB
4078 The "GDB Internals" manual now has an index. It also includes
4079 documentation of `ui_out' functions, GDB coding standards, x86
4080 hardware watchpoints, and memory region attributes.
4082 * GDB's version number moved to ``version.in''
4084 The Makefile variable VERSION has been replaced by the file
4085 ``version.in''. People creating GDB distributions should update the
4086 contents of this file.
4090 GUD support is now a standard part of the EMACS distribution.
4092 *** Changes in GDB 5.0:
4094 * Improved support for debugging FP programs on x86 targets
4096 Unified and much-improved support for debugging floating-point
4097 programs on all x86 targets. In particular, ``info float'' now
4098 displays the FP registers in the same format on all x86 targets, with
4099 greater level of detail.
4101 * Improvements and bugfixes in hardware-assisted watchpoints
4103 It is now possible to watch array elements, struct members, and
4104 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4105 on x86 targets no longer erroneously trigger when the address is
4108 * Improvements in the native DJGPP version of GDB
4110 The distribution now includes all the scripts and auxiliary files
4111 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4112 machines ``out of the box''.
4114 The DJGPP version can now debug programs that use signals. It is
4115 possible to catch signals that happened in the debuggee, deliver
4116 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4117 would kill the program being debugged.) Programs that hook hardware
4118 interrupts (keyboard, timer, etc.) can also be debugged.
4120 It is now possible to debug DJGPP programs that redirect their
4121 standard handles or switch them to raw (as opposed to cooked) mode, or
4122 even close them. The command ``run < foo > bar'' works as expected,
4123 and ``info terminal'' reports useful information about the debuggee's
4124 terminal, including raw/cooked mode, redirection, etc.
4126 The DJGPP version now uses termios functions for console I/O, which
4127 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4130 DOS-style file names with drive letters are now fully supported by
4133 It is now possible to debug DJGPP programs that switch their working
4134 directory. It is also possible to rerun the debuggee any number of
4135 times without restarting GDB; thus, you can use the same setup,
4136 breakpoints, etc. for many debugging sessions.
4138 * New native configurations
4140 ARM GNU/Linux arm*-*-linux*
4141 PowerPC GNU/Linux powerpc-*-linux*
4145 Motorola MCore mcore-*-*
4146 x86 VxWorks i[3456]86-*-vxworks*
4147 PowerPC VxWorks powerpc-*-vxworks*
4148 TI TMS320C80 tic80-*-*
4150 * OBSOLETE configurations
4152 Altos 3068 m68*-altos-*
4153 Convex c1-*-*, c2-*-*
4155 ARM RISCix arm-*-* (as host)
4158 Configurations that have been declared obsolete will be commented out,
4159 but the code will be left in place. If there is no activity to revive
4160 these configurations before the next release of GDB, the sources will
4161 be permanently REMOVED.
4163 * Gould support removed
4165 Support for the Gould PowerNode and NP1 has been removed.
4167 * New features for SVR4
4169 On SVR4 native platforms (such as Solaris), if you attach to a process
4170 without first loading a symbol file, GDB will now attempt to locate and
4171 load symbols from the running process's executable file.
4173 * Many C++ enhancements
4175 C++ support has been greatly improved. Overload resolution now works properly
4176 in almost all cases. RTTI support is on the way.
4178 * Remote targets can connect to a sub-program
4180 A popen(3) style serial-device has been added. This device starts a
4181 sub-process (such as a stand-alone simulator) and then communicates
4182 with that. The sub-program to run is specified using the syntax
4183 ``|<program> <args>'' vis:
4185 (gdb) set remotedebug 1
4186 (gdb) target extended-remote |mn10300-elf-sim program-args
4188 * MIPS 64 remote protocol
4190 A long standing bug in the mips64 remote protocol where by GDB
4191 expected certain 32 bit registers (ex SR) to be transfered as 32
4192 instead of 64 bits has been fixed.
4194 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4195 added to provide backward compatibility with older versions of GDB.
4197 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4199 The command ``set remotebinarydownload'' command has been replaced by
4200 ``set remote X-packet''. Other commands in ``set remote'' family
4201 include ``set remote P-packet''.
4203 * Breakpoint commands accept ranges.
4205 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4206 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4207 ``tracepoint passcount'' also accepts a range of tracepoints.
4209 * ``apropos'' command added.
4211 The ``apropos'' command searches through command names and
4212 documentation strings, printing out matches, making it much easier to
4213 try to find a command that does what you are looking for.
4217 A new machine oriented interface (MI) has been added to GDB. This
4218 interface is designed for debug environments running GDB as a separate
4219 process. This is part of the long term libGDB project. See the
4220 "GDB/MI" chapter of the GDB manual for further information. It can be
4221 enabled by configuring with:
4223 .../configure --enable-gdbmi
4225 *** Changes in GDB-4.18:
4227 * New native configurations
4229 HP-UX 10.20 hppa*-*-hpux10.20
4230 HP-UX 11.x hppa*-*-hpux11.0*
4231 M68K GNU/Linux m68*-*-linux*
4235 Fujitsu FR30 fr30-*-elf*
4236 Intel StrongARM strongarm-*-*
4237 Mitsubishi D30V d30v-*-*
4239 * OBSOLETE configurations
4241 Gould PowerNode, NP1 np1-*-*, pn-*-*
4243 Configurations that have been declared obsolete will be commented out,
4244 but the code will be left in place. If there is no activity to revive
4245 these configurations before the next release of GDB, the sources will
4246 be permanently REMOVED.
4250 As a compatibility experiment, GDB's source files buildsym.h and
4251 buildsym.c have been converted to pure standard C, no longer
4252 containing any K&R compatibility code. We believe that all systems in
4253 use today either come with a standard C compiler, or have a GCC port
4254 available. If this is not true, please report the affected
4255 configuration to bug-gdb@gnu.org immediately. See the README file for
4256 information about getting a standard C compiler if you don't have one
4261 GDB now uses readline 2.2.
4263 * set extension-language
4265 You can now control the mapping between filename extensions and source
4266 languages by using the `set extension-language' command. For instance,
4267 you can ask GDB to treat .c files as C++ by saying
4268 set extension-language .c c++
4269 The command `info extensions' lists all of the recognized extensions
4270 and their associated languages.
4272 * Setting processor type for PowerPC and RS/6000
4274 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4275 you can use the `set processor' command to specify what variant of the
4276 PowerPC family you are debugging. The command
4280 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4281 following PowerPC and RS6000 variants:
4283 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4284 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4286 403GC IBM PowerPC 403GC
4287 505 Motorola PowerPC 505
4288 860 Motorola PowerPC 860 or 850
4289 601 Motorola PowerPC 601
4290 602 Motorola PowerPC 602
4291 603 Motorola/IBM PowerPC 603 or 603e
4292 604 Motorola PowerPC 604 or 604e
4293 750 Motorola/IBM PowerPC 750 or 750
4295 At the moment, this command just tells GDB what to name the
4296 special-purpose processor registers. Since almost all the affected
4297 registers are inaccessible to user-level programs, this command is
4298 only useful for remote debugging in its present form.
4302 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4303 more extensive support for HP-UX. Added features include shared
4304 library support, kernel threads and hardware watchpoints for 11.00,
4305 support for HP's ANSI C and C++ compilers, and a compatibility mode
4306 for xdb and dbx commands.
4310 HP's donation includes the new concept of catchpoints, which is a
4311 generalization of the old catch command. On HP-UX, it is now possible
4312 to catch exec, fork, and vfork, as well as library loading.
4314 This means that the existing catch command has changed; its first
4315 argument now specifies the type of catch to be set up. See the
4316 output of "help catch" for a list of catchpoint types.
4318 * Debugging across forks
4320 On HP-UX, you can choose which process to debug when a fork() happens
4325 HP has donated a curses-based terminal user interface (TUI). To get
4326 it, build with --enable-tui. Although this can be enabled for any
4327 configuration, at present it only works for native HP debugging.
4329 * GDB remote protocol additions
4331 A new protocol packet 'X' that writes binary data is now available.
4332 Default behavior is to try 'X', then drop back to 'M' if the stub
4333 fails to respond. The settable variable `remotebinarydownload'
4334 allows explicit control over the use of 'X'.
4336 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4337 full 64-bit address. The command
4339 set remoteaddresssize 32
4341 can be used to revert to the old behaviour. For existing remote stubs
4342 the change should not be noticed, as the additional address information
4345 In order to assist in debugging stubs, you may use the maintenance
4346 command `packet' to send any text string to the stub. For instance,
4348 maint packet heythere
4350 sends the packet "$heythere#<checksum>". Note that it is very easy to
4351 disrupt a debugging session by sending the wrong packet at the wrong
4354 The compare-sections command allows you to compare section data on the
4355 target to what is in the executable file without uploading or
4356 downloading, by comparing CRC checksums.
4358 * Tracing can collect general expressions
4360 You may now collect general expressions at tracepoints. This requires
4361 further additions to the target-side stub; see tracepoint.c and
4362 doc/agentexpr.texi for further details.
4364 * mask-address variable for Mips
4366 For Mips targets, you may control the zeroing of the upper 32 bits of
4367 a 64-bit address by entering `set mask-address on'. This is mainly
4368 of interest to users of embedded R4xxx and R5xxx processors.
4370 * Higher serial baud rates
4372 GDB's serial code now allows you to specify baud rates 57600, 115200,
4373 230400, and 460800 baud. (Note that your host system may not be able
4374 to achieve all of these rates.)
4378 The i960 configuration now includes an initial implementation of a
4379 builtin simulator, contributed by Jim Wilson.
4382 *** Changes in GDB-4.17:
4384 * New native configurations
4386 Alpha GNU/Linux alpha*-*-linux*
4387 Unixware 2.x i[3456]86-unixware2*
4388 Irix 6.x mips*-sgi-irix6*
4389 PowerPC GNU/Linux powerpc-*-linux*
4390 PowerPC Solaris powerpcle-*-solaris*
4391 Sparc GNU/Linux sparc-*-linux*
4392 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4396 Argonaut Risc Chip (ARC) arc-*-*
4397 Hitachi H8/300S h8300*-*-*
4398 Matsushita MN10200 w/simulator mn10200-*-*
4399 Matsushita MN10300 w/simulator mn10300-*-*
4400 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4401 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4402 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4403 Mitsubishi D10V w/simulator d10v-*-*
4404 Mitsubishi M32R/D w/simulator m32r-*-elf*
4405 Tsqware Sparclet sparclet-*-*
4406 NEC V850 w/simulator v850-*-*
4408 * New debugging protocols
4410 ARM with RDI protocol arm*-*-*
4411 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4412 DDB and LSI variants of PMON protocol mips*-*-*
4413 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4414 PowerPC with SDS protocol powerpc{,le}-*-eabi
4415 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4419 All configurations can now understand and use the DWARF 2 debugging
4420 format. The choice is automatic, if the symbol file contains DWARF 2
4425 GDB now includes basic Java language support. This support is
4426 only useful with Java compilers that produce native machine code.
4428 * solib-absolute-prefix and solib-search-path
4430 For SunOS and SVR4 shared libraries, you may now set the prefix for
4431 loading absolute shared library symbol files, and the search path for
4432 locating non-absolute shared library symbol files.
4434 * Live range splitting
4436 GDB can now effectively debug code for which GCC has performed live
4437 range splitting as part of its optimization. See gdb/doc/LRS for
4438 more details on the expected format of the stabs information.
4442 GDB's support for the GNU Hurd, including thread debugging, has been
4443 updated to work with current versions of the Hurd.
4447 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4448 instruction set. ARM GDB automatically detects when Thumb
4449 instructions are in use, and adjusts disassembly and backtracing
4454 GDB's MIPS target configurations now handle the MIP16 16-bit
4459 GDB now includes support for overlays; if an executable has been
4460 linked such that multiple sections are based at the same address, GDB
4461 will decide which section to use for symbolic info. You can choose to
4462 control the decision manually, using overlay commands, or implement
4463 additional target-side support and use "overlay load-target" to bring
4464 in the overlay mapping. Do "help overlay" for more detail.
4468 The command "info symbol <address>" displays information about
4469 the symbol at the specified address.
4473 The standard remote protocol now includes an extension that allows
4474 asynchronous collection and display of trace data. This requires
4475 extensive support in the target-side debugging stub. Tracing mode
4476 includes a new interaction mode in GDB and new commands: see the
4477 file tracepoint.c for more details.
4481 Configurations for embedded MIPS now include a simulator contributed
4482 by Cygnus Solutions. The simulator supports the instruction sets
4483 of most MIPS variants.
4487 Sparc configurations may now include the ERC32 simulator contributed
4488 by the European Space Agency. The simulator is not built into
4489 Sparc targets by default; configure with --enable-sim to include it.
4493 For target configurations that may include multiple variants of a
4494 basic architecture (such as MIPS and SH), you may now set the
4495 architecture explicitly. "set arch" sets, "info arch" lists
4496 the possible architectures.
4498 *** Changes in GDB-4.16:
4500 * New native configurations
4502 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4503 M68K NetBSD m68k-*-netbsd*
4504 PowerPC AIX 4.x powerpc-*-aix*
4505 PowerPC MacOS powerpc-*-macos*
4506 PowerPC Windows NT powerpcle-*-cygwin32
4507 RS/6000 AIX 4.x rs6000-*-aix4*
4511 ARM with RDP protocol arm-*-*
4512 I960 with MON960 i960-*-coff
4513 MIPS VxWorks mips*-*-vxworks*
4514 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4515 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4517 Matra Sparclet sparclet-*-*
4521 The powerpc-eabi configuration now includes the PSIM simulator,
4522 contributed by Andrew Cagney, with assistance from Mike Meissner.
4523 PSIM is a very elaborate model of the PowerPC, including not only
4524 basic instruction set execution, but also details of execution unit
4525 performance and I/O hardware. See sim/ppc/README for more details.
4529 GDB now works with Solaris 2.5.
4531 * Windows 95/NT native
4533 GDB will now work as a native debugger on Windows 95 and Windows NT.
4534 To build it from source, you must use the "gnu-win32" environment,
4535 which uses a DLL to emulate enough of Unix to run the GNU tools.
4536 Further information, binaries, and sources are available at
4537 ftp.cygnus.com, under pub/gnu-win32.
4539 * dont-repeat command
4541 If a user-defined command includes the command `dont-repeat', then the
4542 command will not be repeated if the user just types return. This is
4543 useful if the command is time-consuming to run, so that accidental
4544 extra keystrokes don't run the same command many times.
4546 * Send break instead of ^C
4548 The standard remote protocol now includes an option to send a break
4549 rather than a ^C to the target in order to interrupt it. By default,
4550 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4552 * Remote protocol timeout
4554 The standard remote protocol includes a new variable `remotetimeout'
4555 that allows you to set the number of seconds before GDB gives up trying
4556 to read from the target. The default value is 2.
4558 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4560 By default GDB will automatically keep track of objects as they are
4561 loaded and unloaded by the dynamic linker. By using the command `set
4562 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4563 when shared library events occur, thus allowing you to set breakpoints
4564 in shared libraries which are explicitly loaded by the inferior.
4566 Note this feature does not work on hpux8. On hpux9 you must link
4567 /usr/lib/end.o into your program. This feature should work
4568 automatically on hpux10.
4570 * Irix 5.x hardware watchpoint support
4572 Irix 5 configurations now support the use of hardware watchpoints.
4574 * Mips protocol "SYN garbage limit"
4576 When debugging a Mips target using the `target mips' protocol, you
4577 may set the number of characters that GDB will ignore by setting
4578 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4579 every character. The default value is 1050.
4581 * Recording and replaying remote debug sessions
4583 If you set `remotelogfile' to the name of a file, gdb will write to it
4584 a recording of a remote debug session. This recording may then be
4585 replayed back to gdb using "gdbreplay". See gdbserver/README for
4586 details. This is useful when you have a problem with GDB while doing
4587 remote debugging; you can make a recording of the session and send it
4588 to someone else, who can then recreate the problem.
4590 * Speedups for remote debugging
4592 GDB includes speedups for downloading and stepping MIPS systems using
4593 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4594 and more efficient S-record downloading.
4596 * Memory use reductions and statistics collection
4598 GDB now uses less memory and reports statistics about memory usage.
4599 Try the `maint print statistics' command, for example.
4601 *** Changes in GDB-4.15:
4603 * Psymtabs for XCOFF
4605 The symbol reader for AIX GDB now uses partial symbol tables. This
4606 can greatly improve startup time, especially for large executables.
4608 * Remote targets use caching
4610 Remote targets now use a data cache to speed up communication with the
4611 remote side. The data cache could lead to incorrect results because
4612 it doesn't know about volatile variables, thus making it impossible to
4613 debug targets which use memory mapped I/O devices. `set remotecache
4614 off' turns the the data cache off.
4616 * Remote targets may have threads
4618 The standard remote protocol now includes support for multiple threads
4619 in the target system, using new protocol commands 'H' and 'T'. See
4620 gdb/remote.c for details.
4624 If GDB is configured with `--enable-netrom', then it will include
4625 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4626 acts as though it is a bank of ROM on the target board, but you can
4627 write into it over the network. GDB's support consists only of
4628 support for fast loading into the emulated ROM; to debug, you must use
4629 another protocol, such as standard remote protocol. The usual
4630 sequence is something like
4632 target nrom <netrom-hostname>
4634 target remote <netrom-hostname>:1235
4638 GDB now includes support for the Apple Macintosh, as a host only. It
4639 may be run as either an MPW tool or as a standalone application, and
4640 it can debug through the serial port. All the usual GDB commands are
4641 available, but to the target command, you must supply "serial" as the
4642 device type instead of "/dev/ttyXX". See mpw-README in the main
4643 directory for more information on how to build. The MPW configuration
4644 scripts */mpw-config.in support only a few targets, and only the
4645 mips-idt-ecoff target has been tested.
4649 GDB configuration now uses autoconf. This is not user-visible,
4650 but does simplify configuration and building.
4654 GDB now supports hpux10.
4656 *** Changes in GDB-4.14:
4658 * New native configurations
4660 x86 FreeBSD i[345]86-*-freebsd
4661 x86 NetBSD i[345]86-*-netbsd
4662 NS32k NetBSD ns32k-*-netbsd
4663 Sparc NetBSD sparc-*-netbsd
4667 A29K VxWorks a29k-*-vxworks
4668 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4669 CPU32 EST-300 emulator m68*-*-est*
4670 PowerPC ELF powerpc-*-elf
4673 * Alpha OSF/1 support for procfs
4675 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4676 possible to attach to running processes. As the mounting of the /proc
4677 filesystem is optional on the Alpha, GDB automatically determines
4678 the availability of /proc during startup. This can lead to problems
4679 if /proc is unmounted after GDB has been started.
4681 * Arguments to user-defined commands
4683 User commands may accept up to 10 arguments separated by whitespace.
4684 Arguments are accessed within the user command via $arg0..$arg9. A
4687 print $arg0 + $arg1 + $arg2
4689 To execute the command use:
4692 Defines the command "adder" which prints the sum of its three arguments.
4693 Note the arguments are text substitutions, so they may reference variables,
4694 use complex expressions, or even perform inferior function calls.
4696 * New `if' and `while' commands
4698 This makes it possible to write more sophisticated user-defined
4699 commands. Both commands take a single argument, which is the
4700 expression to evaluate, and must be followed by the commands to
4701 execute, one per line, if the expression is nonzero, the list being
4702 terminated by the word `end'. The `if' command list may include an
4703 `else' word, which causes the following commands to be executed only
4704 if the expression is zero.
4706 * Fortran source language mode
4708 GDB now includes partial support for Fortran 77. It will recognize
4709 Fortran programs and can evaluate a subset of Fortran expressions, but
4710 variables and functions may not be handled correctly. GDB will work
4711 with G77, but does not yet know much about symbols emitted by other
4714 * Better HPUX support
4716 Most debugging facilities now work on dynamic executables for HPPAs
4717 running hpux9 or later. You can attach to running dynamically linked
4718 processes, but by default the dynamic libraries will be read-only, so
4719 for instance you won't be able to put breakpoints in them. To change
4720 that behavior do the following before running the program:
4726 This will cause the libraries to be mapped private and read-write.
4727 To revert to the normal behavior, do this:
4733 You cannot set breakpoints or examine data in the library until after
4734 the library is loaded if the function/data symbols do not have
4737 GDB can now also read debug symbols produced by the HP C compiler on
4738 HPPAs (sorry, no C++, Fortran or 68k support).
4740 * Target byte order now dynamically selectable
4742 You can choose which byte order to use with a target system, via the
4743 commands "set endian big" and "set endian little", and you can see the
4744 current setting by using "show endian". You can also give the command
4745 "set endian auto", in which case GDB will use the byte order
4746 associated with the executable. Currently, only embedded MIPS
4747 configurations support dynamic selection of target byte order.
4749 * New DOS host serial code
4751 This version uses DPMI interrupts to handle buffered I/O, so you
4752 no longer need to run asynctsr when debugging boards connected to
4755 *** Changes in GDB-4.13:
4757 * New "complete" command
4759 This lists all the possible completions for the rest of the line, if it
4760 were to be given as a command itself. This is intended for use by emacs.
4762 * Trailing space optional in prompt
4764 "set prompt" no longer adds a space for you after the prompt you set. This
4765 allows you to set a prompt which ends in a space or one that does not.
4767 * Breakpoint hit counts
4769 "info break" now displays a count of the number of times the breakpoint
4770 has been hit. This is especially useful in conjunction with "ignore"; you
4771 can ignore a large number of breakpoint hits, look at the breakpoint info
4772 to see how many times the breakpoint was hit, then run again, ignoring one
4773 less than that number, and this will get you quickly to the last hit of
4776 * Ability to stop printing at NULL character
4778 "set print null-stop" will cause GDB to stop printing the characters of
4779 an array when the first NULL is encountered. This is useful when large
4780 arrays actually contain only short strings.
4782 * Shared library breakpoints
4784 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4785 breakpoints in shared libraries before the executable is run.
4787 * Hardware watchpoints
4789 There is a new hardware breakpoint for the watch command for sparclite
4790 targets. See gdb/sparclite/hw_breakpoint.note.
4792 Hardware watchpoints are also now supported under GNU/Linux.
4796 Annotations have been added. These are for use with graphical interfaces,
4797 and are still experimental. Currently only gdba.el uses these.
4799 * Improved Irix 5 support
4801 GDB now works properly with Irix 5.2.
4803 * Improved HPPA support
4805 GDB now works properly with the latest GCC and GAS.
4807 * New native configurations
4809 Sequent PTX4 i[34]86-sequent-ptx4
4810 HPPA running OSF/1 hppa*-*-osf*
4811 Atari TT running SVR4 m68*-*-sysv4*
4812 RS/6000 LynxOS rs6000-*-lynxos*
4816 OS/9000 i[34]86-*-os9k
4817 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4820 * Hitachi SH7000 and E7000-PC ICE support
4822 There is now support for communicating with the Hitachi E7000-PC ICE.
4823 This is available automatically when GDB is configured for the SH.
4827 As usual, a variety of small fixes and improvements, both generic
4828 and configuration-specific. See the ChangeLog for more detail.
4830 *** Changes in GDB-4.12:
4832 * Irix 5 is now supported
4836 GDB-4.12 on the HPPA has a number of changes which make it unable
4837 to debug the output from the currently released versions of GCC and
4838 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4839 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4840 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4843 *** Changes in GDB-4.11:
4845 * User visible changes:
4849 The "set remotedebug" option is now consistent between the mips remote
4850 target, remote targets using the gdb-specific protocol, UDI (AMD's
4851 debug protocol for the 29k) and the 88k bug monitor. It is now an
4852 integer specifying a debug level (normally 0 or 1, but 2 means more
4853 debugging info for the mips target).
4855 * DEC Alpha native support
4857 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4858 debug info, but GDB works fairly well with the DEC compiler and should
4859 work with a future GCC release. See the README file for a few
4860 Alpha-specific notes.
4862 * Preliminary thread implementation
4864 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4866 * LynxOS native and target support for 386
4868 This release has been hosted on LynxOS 2.2, and also can be configured
4869 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4872 * Improvements in C++ mangling/demangling.
4874 This release has much better g++ debugging, specifically in name
4875 mangling/demangling, virtual function calls, print virtual table,
4876 call methods, ...etc.
4878 *** Changes in GDB-4.10:
4880 * User visible changes:
4882 Remote debugging using the GDB-specific (`target remote') protocol now
4883 supports the `load' command. This is only useful if you have some
4884 other way of getting the stub to the target system, and you can put it
4885 somewhere in memory where it won't get clobbered by the download.
4887 Filename completion now works.
4889 When run under emacs mode, the "info line" command now causes the
4890 arrow to point to the line specified. Also, "info line" prints
4891 addresses in symbolic form (as well as hex).
4893 All vxworks based targets now support a user settable option, called
4894 vxworks-timeout. This option represents the number of seconds gdb
4895 should wait for responses to rpc's. You might want to use this if
4896 your vxworks target is, perhaps, a slow software simulator or happens
4897 to be on the far side of a thin network line.
4901 This release contains support for using a DEC alpha as a GDB host for
4902 cross debugging. Native alpha debugging is not supported yet.
4905 *** Changes in GDB-4.9:
4909 This is the first GDB release which is accompanied by a matching testsuite.
4910 The testsuite requires installation of dejagnu, which should be available
4911 via ftp from most sites that carry GNU software.
4915 'Cfront' style demangling has had its name changed to 'ARM' style, to
4916 emphasize that it was written from the specifications in the C++ Annotated
4917 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4918 disclaimers, it still generated too much confusion with users attempting to
4919 use gdb with AT&T cfront.
4923 GDB now uses a standard remote interface to a simulator library.
4924 So far, the library contains simulators for the Zilog Z8001/2, the
4925 Hitachi H8/300, H8/500 and Super-H.
4927 * New targets supported
4929 H8/300 simulator h8300-hitachi-hms or h8300hms
4930 H8/500 simulator h8500-hitachi-hms or h8500hms
4931 SH simulator sh-hitachi-hms or sh
4932 Z8000 simulator z8k-zilog-none or z8ksim
4933 IDT MIPS board over serial line mips-idt-ecoff
4935 Cross-debugging to GO32 targets is supported. It requires a custom
4936 version of the i386-stub.c module which is integrated with the
4937 GO32 memory extender.
4939 * New remote protocols
4941 MIPS remote debugging protocol.
4943 * New source languages supported
4945 This version includes preliminary support for Chill, a Pascal like language
4946 used by telecommunications companies. Chill support is also being integrated
4947 into the GNU compiler, but we don't know when it will be publically available.
4950 *** Changes in GDB-4.8:
4952 * HP Precision Architecture supported
4954 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4955 version of this support was available as a set of patches from the
4956 University of Utah. GDB does not support debugging of programs
4957 compiled with the HP compiler, because HP will not document their file
4958 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4959 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4961 Many problems in the preliminary version have been fixed.
4963 * Faster and better demangling
4965 We have improved template demangling and fixed numerous bugs in the GNU style
4966 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4967 character types (wchar_t) are now supported. Demangling of each symbol is now
4968 only done once, and is cached when the symbol table for a file is read in.
4969 This results in a small increase in memory usage for C programs, a moderate
4970 increase in memory usage for C++ programs, and a fantastic speedup in
4973 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4974 from the specifications in the Annotated Reference Manual, which AT&T's
4975 compiler does not actually implement.
4977 * G++ multiple inheritance compiler problem
4979 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4980 inheritance lattices was reworked to properly discover ambiguities. We
4981 recently found an example which causes this new algorithm to fail in a
4982 very subtle way, producing bad debug information for those classes.
4983 The file 'gcc.patch' (in this directory) can be applied to gcc to
4984 circumvent the problem. A future GCC release will contain a complete
4987 The previous G++ debug info problem (mentioned below for the gdb-4.7
4988 release) is fixed in gcc version 2.3.2.
4990 * Improved configure script
4992 The `configure' script will now attempt to guess your system type if
4993 you don't supply a host system type. The old scheme of supplying a
4994 host system triplet is preferable over using this. All the magic is
4995 done in the new `config.guess' script. Examine it for details.
4997 We have also brought our configure script much more in line with the FSF's
4998 version. It now supports the --with-xxx options. In particular,
4999 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5000 The resulting GDB will not be able to read arbitrary object file formats --
5001 only the format ``expected'' to be used on the configured target system.
5002 We hope to make this the default in a future release.
5004 * Documentation improvements
5006 There's new internal documentation on how to modify GDB, and how to
5007 produce clean changes to the code. We implore people to read it
5008 before submitting changes.
5010 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5011 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5012 `info' files are also provided. To build `info' files from scratch,
5013 you will need the latest `makeinfo' release, which will be available in
5014 a future texinfo-X.Y release.
5016 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5017 We're not sure exactly which versions have this problem, but it has
5018 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5019 or better. If that isn't possible, there is a patch in
5020 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5021 around this problem.
5025 GDB now supports array constants that can be used in expressions typed in by
5026 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5027 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5030 The new directory `gdb/sparclite' contains a program that demonstrates
5031 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5033 * New native hosts supported
5035 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5036 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5038 * New targets supported
5040 AMD 29k family via UDI a29k-amd-udi or udi29k
5042 * New file formats supported
5044 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5045 HPUX core files, and SCO 3.2v2 core files.
5049 Attaching to processes now works again; thanks for the many bug reports.
5051 We have also stomped on a bunch of core dumps caused by
5052 printf_filtered("%s") problems.
5054 We eliminated a copyright problem on the rpc and ptrace header files
5055 for VxWorks, which was discovered at the last minute during the 4.7
5056 release. You should now be able to build a VxWorks GDB.
5058 You can now interrupt gdb while an attached process is running. This
5059 will cause the attached process to stop, and give control back to GDB.
5061 We fixed problems caused by using too many file descriptors
5062 for reading symbols from object files and libraries. This was
5063 especially a problem for programs that used many (~100) shared
5066 The `step' command now only enters a subroutine if there is line number
5067 information for the subroutine. Otherwise it acts like the `next'
5068 command. Previously, `step' would enter subroutines if there was
5069 any debugging information about the routine. This avoids problems
5070 when using `cc -g1' on MIPS machines.
5072 * Internal improvements
5074 GDB's internal interfaces have been improved to make it easier to support
5075 debugging of multiple languages in the future.
5077 GDB now uses a common structure for symbol information internally.
5078 Minimal symbols (derived from linkage symbols in object files), partial
5079 symbols (from a quick scan of debug information), and full symbols
5080 contain a common subset of information, making it easier to write
5081 shared code that handles any of them.
5083 * New command line options
5085 We now accept --silent as an alias for --quiet.
5089 The memory-mapped-malloc library is now licensed under the GNU Library
5090 General Public License.
5092 *** Changes in GDB-4.7:
5094 * Host/native/target split
5096 GDB has had some major internal surgery to untangle the support for
5097 hosts and remote targets. Now, when you configure GDB for a remote
5098 target, it will no longer load in all of the support for debugging
5099 local programs on the host. When fully completed and tested, this will
5100 ensure that arbitrary host/target combinations are possible.
5102 The primary conceptual shift is to separate the non-portable code in
5103 GDB into three categories. Host specific code is required any time GDB
5104 is compiled on that host, regardless of the target. Target specific
5105 code relates to the peculiarities of the target, but can be compiled on
5106 any host. Native specific code is everything else: it can only be
5107 built when the host and target are the same system. Child process
5108 handling and core file support are two common `native' examples.
5110 GDB's use of /proc for controlling Unix child processes is now cleaner.
5111 It has been split out into a single module under the `target_ops' vector,
5112 plus two native-dependent functions for each system that uses /proc.
5114 * New hosts supported
5116 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5117 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5118 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5120 * New targets supported
5122 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5123 68030 and CPU32 m68030-*-*, m68332-*-*
5125 * New native hosts supported
5127 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5128 (386bsd is not well tested yet)
5129 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5131 * New file formats supported
5133 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5134 supports reading of `a.out.adobe' object files, which are an a.out
5135 format extended with minimal information about multiple sections.
5139 `show copying' is the same as the old `info copying'.
5140 `show warranty' is the same as `info warrantee'.
5141 These were renamed for consistency. The old commands continue to work.
5143 `info handle' is a new alias for `info signals'.
5145 You can now define pre-command hooks, which attach arbitrary command
5146 scripts to any command. The commands in the hook will be executed
5147 prior to the user's command. You can also create a hook which will be
5148 executed whenever the program stops. See gdb.texinfo.
5152 We now deal with Cfront style name mangling, and can even extract type
5153 info from mangled symbols. GDB can automatically figure out which
5154 symbol mangling style your C++ compiler uses.
5156 Calling of methods and virtual functions has been improved as well.
5160 The crash that occured when debugging Sun Ansi-C compiled binaries is
5161 fixed. This was due to mishandling of the extra N_SO stabs output
5164 We also finally got Ultrix 4.2 running in house, and fixed core file
5165 support, with help from a dozen people on the net.
5167 John M. Farrell discovered that the reason that single-stepping was so
5168 slow on all of the Mips based platforms (primarily SGI and DEC) was
5169 that we were trying to demangle and lookup a symbol used for internal
5170 purposes on every instruction that was being stepped through. Changing
5171 the name of that symbol so that it couldn't be mistaken for a C++
5172 mangled symbol sped things up a great deal.
5174 Rich Pixley sped up symbol lookups in general by getting much smarter
5175 about when C++ symbol mangling is necessary. This should make symbol
5176 completion (TAB on the command line) much faster. It's not as fast as
5177 we'd like, but it's significantly faster than gdb-4.6.
5181 A new user controllable variable 'call_scratch_address' can
5182 specify the location of a scratch area to be used when GDB
5183 calls a function in the target. This is necessary because the
5184 usual method of putting the scratch area on the stack does not work
5185 in systems that have separate instruction and data spaces.
5187 We integrated changes to support the 29k UDI (Universal Debugger
5188 Interface), but discovered at the last minute that we didn't have all
5189 of the appropriate copyright paperwork. We are working with AMD to
5190 resolve this, and hope to have it available soon.
5194 We have sped up the remote serial line protocol, especially for targets
5195 with lots of registers. It now supports a new `expedited status' ('T')
5196 message which can be used in place of the existing 'S' status message.
5197 This allows the remote stub to send only the registers that GDB
5198 needs to make a quick decision about single-stepping or conditional
5199 breakpoints, eliminating the need to fetch the entire register set for
5200 each instruction being stepped through.
5202 The GDB remote serial protocol now implements a write-through cache for
5203 registers, only re-reading the registers if the target has run.
5205 There is also a new remote serial stub for SPARC processors. You can
5206 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5207 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5208 processor with a serial port.
5212 Configure.in files have become much easier to read and modify. A new
5213 `table driven' format makes it more obvious what configurations are
5214 supported, and what files each one uses.
5218 There is a new opcodes library which will eventually contain all of the
5219 disassembly routines and opcode tables. At present, it only contains
5220 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5221 disassembler (binutils/objdump) to share these routines.
5223 The libiberty library is now copylefted under the GNU Library General
5224 Public License. This allows more liberal use, and was done so libg++
5225 can use it. This makes no difference to GDB, since the Library License
5226 grants all the rights from the General Public License.
5230 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5231 reference to the stabs symbol info used by the debugger. It is (as far
5232 as we know) the only published document on this fascinating topic. We
5233 encourage you to read it, compare it to the stabs information on your
5234 system, and send improvements on the document in general (to
5235 bug-gdb@prep.ai.mit.edu).
5237 And, of course, many bugs have been fixed.
5240 *** Changes in GDB-4.6:
5242 * Better support for C++ function names
5244 GDB now accepts as input the "demangled form" of C++ overloaded function
5245 names and member function names, and can do command completion on such names
5246 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5247 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5248 Make use of command completion, it is your friend.
5250 GDB also now accepts a variety of C++ mangled symbol formats. They are
5251 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5252 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5253 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5254 for the list of formats.
5256 * G++ symbol mangling problem
5258 Recent versions of gcc have a bug in how they emit debugging information for
5259 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5260 directory) can be applied to gcc to fix the problem. Alternatively, if you
5261 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5262 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5263 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5266 * New 'maintenance' command
5268 All of the commands related to hacking GDB internals have been moved out of
5269 the main command set, and now live behind the 'maintenance' command. This
5270 can also be abbreviated as 'mt'. The following changes were made:
5272 dump-me -> maintenance dump-me
5273 info all-breakpoints -> maintenance info breakpoints
5274 printmsyms -> maintenance print msyms
5275 printobjfiles -> maintenance print objfiles
5276 printpsyms -> maintenance print psymbols
5277 printsyms -> maintenance print symbols
5279 The following commands are new:
5281 maintenance demangle Call internal GDB demangler routine to
5282 demangle a C++ link name and prints the result.
5283 maintenance print type Print a type chain for a given symbol
5285 * Change to .gdbinit file processing
5287 We now read the $HOME/.gdbinit file before processing the argv arguments
5288 (e.g. reading symbol files or core files). This allows global parameters to
5289 be set, which will apply during the symbol reading. The ./.gdbinit is still
5290 read after argv processing.
5292 * New hosts supported
5294 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5296 GNU/Linux support i386-unknown-linux or linux
5298 We are also including code to support the HP/PA running BSD and HPUX. This
5299 is almost guaranteed not to work, as we didn't have time to test or build it
5300 for this release. We are including it so that the more adventurous (or
5301 masochistic) of you can play with it. We also had major problems with the
5302 fact that the compiler that we got from HP doesn't support the -g option.
5305 * New targets supported
5307 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5309 * More smarts about finding #include files
5311 GDB now remembers the compilation directory for all include files, and for
5312 all files from which C is generated (like yacc and lex sources). This
5313 greatly improves GDB's ability to find yacc/lex sources, and include files,
5314 especially if you are debugging your program from a directory different from
5315 the one that contains your sources.
5317 We also fixed a bug which caused difficulty with listing and setting
5318 breakpoints in include files which contain C code. (In the past, you had to
5319 try twice in order to list an include file that you hadn't looked at before.)
5321 * Interesting infernals change
5323 GDB now deals with arbitrary numbers of sections, where the symbols for each
5324 section must be relocated relative to that section's landing place in the
5325 target's address space. This work was needed to support ELF with embedded
5326 stabs used by Solaris-2.0.
5328 * Bug fixes (of course!)
5330 There have been loads of fixes for the following things:
5331 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5332 i960, stabs, DOS(GO32), procfs, etc...
5334 See the ChangeLog for details.
5336 *** Changes in GDB-4.5:
5338 * New machines supported (host and target)
5340 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5342 SGI Irix-4.x mips-sgi-irix4 or iris4
5344 * New malloc package
5346 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5347 Mmalloc is capable of handling mutiple heaps of memory. It is also
5348 capable of saving a heap to a file, and then mapping it back in later.
5349 This can be used to greatly speedup the startup of GDB by using a
5350 pre-parsed symbol table which lives in a mmalloc managed heap. For
5351 more details, please read mmalloc/mmalloc.texi.
5355 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5356 'help info proc' for details.
5358 * MIPS ecoff symbol table format
5360 The code that reads MIPS symbol table format is now supported on all hosts.
5361 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5364 * File name changes for MS-DOS
5366 Many files in the config directories have been renamed to make it easier to
5367 support GDB on MS-DOSe systems (which have very restrictive file name
5368 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5369 environment) is close to working but has some remaining problems. Note
5370 that debugging of DOS programs is not supported, due to limitations
5371 in the ``operating system'', but it can be used to host cross-debugging.
5373 * Cross byte order fixes
5375 Many fixes have been made to support cross debugging of Sparc and MIPS
5376 targets from hosts whose byte order differs.
5378 * New -mapped and -readnow options
5380 If memory-mapped files are available on your system through the 'mmap'
5381 system call, you can use the -mapped option on the `file' or
5382 `symbol-file' commands to cause GDB to write the symbols from your
5383 program into a reusable file. If the program you are debugging is
5384 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5385 Future GDB debugging sessions will notice the presence of this file,
5386 and will quickly map in symbol information from it, rather than reading
5387 the symbol table from the executable program. Using the '-mapped'
5388 option in a GDB `file' or `symbol-file' command has the same effect as
5389 starting GDB with the '-mapped' command-line option.
5391 You can cause GDB to read the entire symbol table immediately by using
5392 the '-readnow' option with any of the commands that load symbol table
5393 information (or on the GDB command line). This makes the command
5394 slower, but makes future operations faster.
5396 The -mapped and -readnow options are typically combined in order to
5397 build a `fred.syms' file that contains complete symbol information.
5398 A simple GDB invocation to do nothing but build a `.syms' file for future
5401 gdb -batch -nx -mapped -readnow programname
5403 The `.syms' file is specific to the host machine on which GDB is run.
5404 It holds an exact image of GDB's internal symbol table. It cannot be
5405 shared across multiple host platforms.
5407 * longjmp() handling
5409 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5410 siglongjmp() without losing control. This feature has not yet been ported to
5411 all systems. It currently works on many 386 platforms, all MIPS-based
5412 platforms (SGI, DECstation, etc), and Sun3/4.
5416 Preliminary work has been put in to support the new Solaris OS from Sun. At
5417 this time, it can control and debug processes, but it is not capable of
5422 As always, many many bug fixes. The major areas were with g++, and mipsread.
5423 People using the MIPS-based platforms should experience fewer mysterious
5424 crashes and trashed symbol tables.
5426 *** Changes in GDB-4.4:
5428 * New machines supported (host and target)
5430 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5432 BSD Reno on Vax vax-dec-bsd
5433 Ultrix on Vax vax-dec-ultrix
5435 * New machines supported (target)
5437 AMD 29000 embedded, using EBMON a29k-none-none
5441 GDB continues to improve its handling of C++. `References' work better.
5442 The demangler has also been improved, and now deals with symbols mangled as
5443 per the Annotated C++ Reference Guide.
5445 GDB also now handles `stabs' symbol information embedded in MIPS
5446 `ecoff' symbol tables. Since the ecoff format was not easily
5447 extensible to handle new languages such as C++, this appeared to be a
5448 good way to put C++ debugging info into MIPS binaries. This option
5449 will be supported in the GNU C compiler, version 2, when it is
5452 * New features for SVR4
5454 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5455 shared libraries. Debugging dynamically linked programs should present
5456 only minor differences from debugging statically linked programs.
5458 The `info proc' command will print out information about any process
5459 on an SVR4 system (including the one you are debugging). At the moment,
5460 it prints the address mappings of the process.
5462 If you bring up GDB on another SVR4 system, please send mail to
5463 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5465 * Better dynamic linking support in SunOS
5467 Reading symbols from shared libraries which contain debugging symbols
5468 now works properly. However, there remain issues such as automatic
5469 skipping of `transfer vector' code during function calls, which
5470 make it harder to debug code in a shared library, than to debug the
5471 same code linked statically.
5475 GDB is now using the latest `getopt' routines from the FSF. This
5476 version accepts the -- prefix for options with long names. GDB will
5477 continue to accept the old forms (-option and +option) as well.
5478 Various single letter abbreviations for options have been explicity
5479 added to the option table so that they won't get overshadowed in the
5480 future by other options that begin with the same letter.
5484 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5485 Many assorted bugs have been handled. Many more remain to be handled.
5486 See the various ChangeLog files (primarily in gdb and bfd) for details.
5489 *** Changes in GDB-4.3:
5491 * New machines supported (host and target)
5493 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5494 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5495 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5497 * Almost SCO Unix support
5499 We had hoped to support:
5500 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5501 (except for core file support), but we discovered very late in the release
5502 that it has problems with process groups that render gdb unusable. Sorry
5503 about that. I encourage people to fix it and post the fixes.
5505 * Preliminary ELF and DWARF support
5507 GDB can read ELF object files on System V Release 4, and can handle
5508 debugging records for C, in DWARF format, in ELF files. This support
5509 is preliminary. If you bring up GDB on another SVR4 system, please
5510 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5515 GDB now uses the latest `readline' library. One user-visible change
5516 is that two tabs will list possible command completions, which previously
5517 required typing M-? (meta-question mark, or ESC ?).
5521 The `stepi' bug that many of you noticed has been squashed.
5522 Many bugs in C++ have been handled. Many more remain to be handled.
5523 See the various ChangeLog files (primarily in gdb and bfd) for details.
5525 * State of the MIPS world (in case you wondered):
5527 GDB can understand the symbol tables emitted by the compilers
5528 supplied by most vendors of MIPS-based machines, including DEC. These
5529 symbol tables are in a format that essentially nobody else uses.
5531 Some versions of gcc come with an assembler post-processor called
5532 mips-tfile. This program is required if you want to do source-level
5533 debugging of gcc-compiled programs. I believe FSF does not ship
5534 mips-tfile with gcc version 1, but it will eventually come with gcc
5537 Debugging of g++ output remains a problem. g++ version 1.xx does not
5538 really support it at all. (If you're lucky, you should be able to get
5539 line numbers and stack traces to work, but no parameters or local
5540 variables.) With some work it should be possible to improve the
5543 When gcc version 2 is released, you will have somewhat better luck.
5544 However, even then you will get confusing results for inheritance and
5547 We will eventually provide full debugging of g++ output on
5548 DECstations. This will probably involve some kind of stabs-in-ecoff
5549 encapulation, but the details have not been worked out yet.
5552 *** Changes in GDB-4.2:
5554 * Improved configuration
5556 Only one copy of `configure' exists now, and it is not self-modifying.
5557 Porting BFD is simpler.
5561 The `step' and `next' commands now only stop at the first instruction
5562 of a source line. This prevents the multiple stops that used to occur
5563 in switch statements, for-loops, etc. `Step' continues to stop if a
5564 function that has debugging information is called within the line.
5568 Lots of small bugs fixed. More remain.
5570 * New host supported (not target)
5572 Intel 386 PC clone running Mach i386-none-mach
5575 *** Changes in GDB-4.1:
5577 * Multiple source language support
5579 GDB now has internal scaffolding to handle several source languages.
5580 It determines the type of each source file from its filename extension,
5581 and will switch expression parsing and number formatting to match the
5582 language of the function in the currently selected stack frame.
5583 You can also specifically set the language to be used, with
5584 `set language c' or `set language modula-2'.
5588 GDB now has preliminary support for the GNU Modula-2 compiler,
5589 currently under development at the State University of New York at
5590 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5591 continue through the fall of 1991 and into 1992.
5593 Other Modula-2 compilers are currently not supported, and attempting to
5594 debug programs compiled with them will likely result in an error as the
5595 symbol table is read. Feel free to work on it, though!
5597 There are hooks in GDB for strict type checking and range checking,
5598 in the `Modula-2 philosophy', but they do not currently work.
5602 GDB can now write to executable and core files (e.g. patch
5603 a variable's value). You must turn this switch on, specify
5604 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5605 by assigning a new value to a variable. Modifications take
5608 * Automatic SunOS shared library reading
5610 When you run your program, GDB automatically determines where its
5611 shared libraries (if any) have been loaded, and reads their symbols.
5612 The `share' command is no longer needed. This also works when
5613 examining core files.
5617 You can specify the number of lines that the `list' command shows.
5620 * New machines supported (host and target)
5622 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5623 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5624 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5626 * New hosts supported (not targets)
5628 IBM RT/PC: romp-ibm-aix or rtpc
5630 * New targets supported (not hosts)
5632 AMD 29000 embedded with COFF a29k-none-coff
5633 AMD 29000 embedded with a.out a29k-none-aout
5634 Ultracomputer remote kernel debug a29k-nyu-kern
5636 * New remote interfaces
5642 *** Changes in GDB-4.0:
5646 Wide output is wrapped at good places to make the output more readable.
5648 Gdb now supports cross-debugging from a host machine of one type to a
5649 target machine of another type. Communication with the target system
5650 is over serial lines. The ``target'' command handles connecting to the
5651 remote system; the ``load'' command will download a program into the
5652 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5653 also supports debugging of realtime processes running under VxWorks,
5654 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5655 stub on the target system.
5657 New CPUs supported include the AMD 29000 and Intel 960.
5659 GDB now reads object files and symbol tables via a ``binary file''
5660 library, which allows a single copy of GDB to debug programs of multiple
5661 object file types such as a.out and coff.
5663 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5664 refcard.dvi and refcard.ps are available to format it).
5667 * Control-Variable user interface simplified
5669 All variables that control the operation of the debugger can be set
5670 by the ``set'' command, and displayed by the ``show'' command.
5672 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5673 ``Show prompt'' produces the response:
5674 Gdb's prompt is new-gdb=>.
5676 What follows are the NEW set commands. The command ``help set'' will
5677 print a complete list of old and new set commands. ``help set FOO''
5678 will give a longer description of the variable FOO. ``show'' will show
5679 all of the variable descriptions and their current settings.
5681 confirm on/off: Enables warning questions for operations that are
5682 hard to recover from, e.g. rerunning the program while
5683 it is already running. Default is ON.
5685 editing on/off: Enables EMACS style command line editing
5686 of input. Previous lines can be recalled with
5687 control-P, the current line can be edited with control-B,
5688 you can search for commands with control-R, etc.
5691 history filename NAME: NAME is where the gdb command history
5692 will be stored. The default is .gdb_history,
5693 or the value of the environment variable
5696 history size N: The size, in commands, of the command history. The
5697 default is 256, or the value of the environment variable
5700 history save on/off: If this value is set to ON, the history file will
5701 be saved after exiting gdb. If set to OFF, the
5702 file will not be saved. The default is OFF.
5704 history expansion on/off: If this value is set to ON, then csh-like
5705 history expansion will be performed on
5706 command line input. The default is OFF.
5708 radix N: Sets the default radix for input and output. It can be set
5709 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5710 in the current radix, so "set radix 10" is always a no-op.
5712 height N: This integer value is the number of lines on a page. Default
5713 is 24, the current `stty rows'' setting, or the ``li#''
5714 setting from the termcap entry matching the environment
5717 width N: This integer value is the number of characters on a line.
5718 Default is 80, the current `stty cols'' setting, or the ``co#''
5719 setting from the termcap entry matching the environment
5722 Note: ``set screensize'' is obsolete. Use ``set height'' and
5723 ``set width'' instead.
5725 print address on/off: Print memory addresses in various command displays,
5726 such as stack traces and structure values. Gdb looks
5727 more ``symbolic'' if you turn this off; it looks more
5728 ``machine level'' with it on. Default is ON.
5730 print array on/off: Prettyprint arrays. New convenient format! Default
5733 print demangle on/off: Print C++ symbols in "source" form if on,
5736 print asm-demangle on/off: Same, for assembler level printouts
5739 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5742 * Support for Epoch Environment.
5744 The epoch environment is a version of Emacs v18 with windowing. One
5745 new command, ``inspect'', is identical to ``print'', except that if you
5746 are running in the epoch environment, the value is printed in its own
5750 * Support for Shared Libraries
5752 GDB can now debug programs and core files that use SunOS shared libraries.
5753 Symbols from a shared library cannot be referenced
5754 before the shared library has been linked with the program (this
5755 happens after you type ``run'' and before the function main() is entered).
5756 At any time after this linking (including when examining core files
5757 from dynamically linked programs), gdb reads the symbols from each
5758 shared library when you type the ``sharedlibrary'' command.
5759 It can be abbreviated ``share''.
5761 sharedlibrary REGEXP: Load shared object library symbols for files
5762 matching a unix regular expression. No argument
5763 indicates to load symbols for all shared libraries.
5765 info sharedlibrary: Status of loaded shared libraries.
5770 A watchpoint stops execution of a program whenever the value of an
5771 expression changes. Checking for this slows down execution
5772 tremendously whenever you are in the scope of the expression, but is
5773 quite useful for catching tough ``bit-spreader'' or pointer misuse
5774 problems. Some machines such as the 386 have hardware for doing this
5775 more quickly, and future versions of gdb will use this hardware.
5777 watch EXP: Set a watchpoint (breakpoint) for an expression.
5779 info watchpoints: Information about your watchpoints.
5781 delete N: Deletes watchpoint number N (same as breakpoints).
5782 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5783 enable N: Re-enables watchpoint number N (same as breakpoints).
5786 * C++ multiple inheritance
5788 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5791 * C++ exception handling
5793 Gdb now supports limited C++ exception handling. Besides the existing
5794 ability to breakpoint on an exception handler, gdb can breakpoint on
5795 the raising of an exception (before the stack is peeled back to the
5798 catch FOO: If there is a FOO exception handler in the dynamic scope,
5799 set a breakpoint to catch exceptions which may be raised there.
5800 Multiple exceptions (``catch foo bar baz'') may be caught.
5802 info catch: Lists all exceptions which may be caught in the
5803 current stack frame.
5806 * Minor command changes
5808 The command ``call func (arg, arg, ...)'' now acts like the print
5809 command, except it does not print or save a value if the function's result
5810 is void. This is similar to dbx usage.
5812 The ``up'' and ``down'' commands now always print the frame they end up
5813 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5814 frames without printing.
5816 * New directory command
5818 'dir' now adds directories to the FRONT of the source search path.
5819 The path starts off empty. Source files that contain debug information
5820 about the directory in which they were compiled can be found even
5821 with an empty path; Sun CC and GCC include this information. If GDB can't
5822 find your source file in the current directory, type "dir .".
5824 * Configuring GDB for compilation
5826 For normal use, type ``./configure host''. See README or gdb.texinfo
5829 GDB now handles cross debugging. If you are remotely debugging between
5830 two different machines, type ``./configure host -target=targ''.
5831 Host is the machine where GDB will run; targ is the machine
5832 where the program that you are debugging will run.