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.
13 * New Python-based convenience functions:
15 ** $_caller_is(name [, number_of_frames])
16 ** $_caller_matches(regexp [, number_of_frames])
17 ** $_any_caller_is(name [, number_of_frames])
18 ** $_any_caller_matches(regexp [, number_of_frames])
22 queue-signal signal-name-or-number
23 Queue a signal to be delivered to the thread when it is resumed.
25 * On resume, GDB now always passes the signal the program had stopped
26 for to the thread the signal was sent to, even if the user changed
27 threads before resuming. Previously GDB would often (but not
28 always) deliver the signal to the thread that happens to be current
31 * Conversely, the "signal" command now consistently delivers the
32 requested signal to the current thread. GDB now asks for
33 confirmation if the program had stopped for a signal and the user
34 switched threads meanwhile.
36 * "breakpoint always-inserted" modes "off" and "auto" merged.
38 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
39 won't remove breakpoints from the target until all threads stop,
40 even in non-stop mode. The "auto" mode has been removed, and "off"
41 is now the default mode.
45 ** The -list-thread-groups command outputs an exit-code field for
46 inferiors that have exited.
50 Support for these obsolete configurations has been removed.
56 *** Changes in GDB 7.8
58 * New command line options
61 This is an alias for the --data-directory option.
63 * GDB supports printing and modifying of variable length automatic arrays
64 as specified in ISO C99.
66 * The ARM simulator now supports instruction level tracing
67 with or without disassembly.
71 GDB now has support for scripting using Guile. Whether this is
72 available is determined at configure time.
73 Guile version 2.0 or greater is required.
74 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
76 * New commands (for set/show, see "New options" below)
80 Invoke CODE by passing it to the Guile interpreter.
84 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
86 info auto-load guile-scripts [regexp]
87 Print the list of automatically loaded Guile scripts.
89 * The source command is now capable of sourcing Guile scripts.
90 This feature is dependent on the debugger being built with Guile support.
94 set print symbol-loading (off|brief|full)
95 show print symbol-loading
96 Control whether to print informational messages when loading symbol
97 information for a file. The default is "full", but when debugging
98 programs with large numbers of shared libraries the amount of output
101 set guile print-stack (none|message|full)
102 show guile print-stack
103 Show a stack trace when an error is encountered in a Guile script.
105 set auto-load guile-scripts (on|off)
106 show auto-load guile-scripts
107 Control auto-loading of Guile script files.
109 maint ada set ignore-descriptive-types (on|off)
110 maint ada show ignore-descriptive-types
111 Control whether the debugger should ignore descriptive types in Ada
112 programs. The default is not to ignore the descriptive types. See
113 the user manual for more details on descriptive types and the intended
114 usage of this option.
116 set auto-connect-native-target
118 Control whether GDB is allowed to automatically connect to the
119 native target for the run, attach, etc. commands when not connected
120 to any target yet. See also "target native" below.
122 set record btrace replay-memory-access (read-only|read-write)
123 show record btrace replay-memory-access
124 Control what memory accesses are allowed during replay.
126 maint set target-async (on|off)
127 maint show target-async
128 This controls whether GDB targets operate in syncronous or
129 asyncronous mode. Normally the default is asyncronous, if it is
130 available; but this can be changed to more easily debug problems
131 occurring only in syncronous mode.
133 set mi-async (on|off)
135 Control whether MI asynchronous mode is preferred. This supersedes
136 "set target-async" of previous GDB versions.
138 * "set target-async" is deprecated as a CLI option and is now an alias
139 for "set mi-async" (only puts MI into async mode).
141 * Background execution commands (e.g., "c&", "s&", etc.) are now
142 possible ``out of the box'' if the target supports them. Previously
143 the user would need to explicitly enable the possibility with the
144 "set target-async on" command.
146 * New features in the GDB remote stub, GDBserver
148 ** New option --debug-format=option1[,option2,...] allows one to add
149 additional text to each output. At present only timestamps
150 are supported: --debug-format=timestamps.
151 Timestamps can also be turned on with the
152 "monitor set debug-format timestamps" command from GDB.
154 * The 'record instruction-history' command now starts counting instructions
155 at one. This also affects the instruction ranges reported by the
156 'record function-call-history' command when given the /i modifier.
158 * The command 'record function-call-history' supports a new modifier '/c' to
159 indent the function names based on their call stack depth.
160 The fields for the '/i' and '/l' modifier have been reordered.
161 The source line range is now prefixed with 'at'.
162 The instruction range is now prefixed with 'inst'.
163 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
164 "record instruction-history" and "list" commands.
166 * The ranges given as arguments to the 'record function-call-history' and
167 'record instruction-history' commands are now inclusive.
169 * The btrace record target now supports the 'record goto' command.
170 For locations inside the execution trace, the back trace is computed
171 based on the information stored in the execution trace.
173 * The btrace record target supports limited reverse execution and replay.
174 The target does not record data and therefore does not allow reading
177 * The "catch syscall" command now works on s390*-linux* targets.
179 * The "compare-sections" command is no longer specific to target
180 remote. It now works with all targets.
182 * All native targets are now consistently called "native".
183 Consequently, the "target child", "target GNU", "target djgpp",
184 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
185 commands have been replaced with "target native". The QNX/NTO port
186 leaves the "procfs" target in place and adds a "native" target for
187 consistency with other ports. The impact on users should be minimal
188 as these commands previously either throwed an error, or were
189 no-ops. The target's name is visible in the output of the following
190 commands: "help target", "info target", "info files", "maint print
193 * The "target native" command now connects to the native target. This
194 can be used to launch native programs even when "set
195 auto-connect-native-target" is set to off.
197 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
199 * Support for Intel(R) AVX-512 registers on GNU/Linux.
200 Support displaying and modifying Intel(R) AVX-512 registers
201 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
205 qXfer:btrace:read's annex
206 The qXfer:btrace:read packet supports a new annex 'delta' to read
207 branch trace incrementally.
211 ** Valid Python operations on gdb.Value objects representing
212 structs/classes invoke the corresponding overloaded operators if
214 ** New `Xmethods' feature in the Python API. Xmethods are
215 additional methods or replacements for existing methods of a C++
216 class. This feature is useful for those cases where a method
217 defined in C++ source code could be inlined or optimized out by
218 the compiler, making it unavailable to GDB.
221 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
223 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
224 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
225 its alias "share", instead.
227 * The commands "set remotebaud" and "show remotebaud" are no longer
228 supported. Use "set serial baud" and "show serial baud" (respectively)
233 ** A new option "-gdb-set mi-async" replaces "-gdb-set
234 target-async". The latter is left as a deprecated alias of the
235 former for backward compatibility. If the target supports it,
236 CLI background execution commands are now always possible by
237 default, independently of whether the frontend stated a
238 preference for asynchronous execution with "-gdb-set mi-async".
239 Previously "-gdb-set target-async off" affected both MI execution
240 commands and CLI execution commands.
242 *** Changes in GDB 7.7
244 * Improved support for process record-replay and reverse debugging on
245 arm*-linux* targets. Support for thumb32 and syscall instruction
246 recording has been added.
248 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
250 * GDB now supports Fission DWP file format version 2.
251 http://gcc.gnu.org/wiki/DebugFission
253 * New convenience function "$_isvoid", to check whether an expression
254 is void. A void expression is an expression where the type of the
255 result is "void". For example, some convenience variables may be
256 "void" when evaluated (e.g., "$_exitcode" before the execution of
257 the program being debugged; or an undefined convenience variable).
258 Another example, when calling a function whose return type is
261 * The "maintenance print objfiles" command now takes an optional regexp.
263 * The "catch syscall" command now works on arm*-linux* targets.
265 * GDB now consistently shows "<not saved>" when printing values of
266 registers the debug info indicates have not been saved in the frame
267 and there's nowhere to retrieve them from
268 (callee-saved/call-clobbered registers):
273 (gdb) info registers rax
276 Before, the former would print "<optimized out>", and the latter
277 "*value not available*".
279 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
284 ** Frame filters and frame decorators have been added.
285 ** Temporary breakpoints are now supported.
286 ** Line tables representation has been added.
287 ** New attribute 'parent_type' for gdb.Field objects.
288 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
289 ** New attribute 'name' for gdb.Type objects.
293 Nios II ELF nios2*-*-elf
294 Nios II GNU/Linux nios2*-*-linux
295 Texas Instruments MSP430 msp430*-*-elf
297 * Removed native configurations
299 Support for these a.out NetBSD and OpenBSD obsolete configurations has
300 been removed. ELF variants of these configurations are kept supported.
302 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
303 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
304 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
305 i[34567]86-*-openbsd3.[0-3]
306 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
307 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
308 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
312 Like "catch throw", but catches a re-thrown exception.
314 Renamed from old "maint check-symtabs".
316 Perform consistency checks on symtabs.
318 Expand symtabs matching an optional regexp.
321 Display the details of GDB configure-time options.
323 maint set|show per-command
324 maint set|show per-command space
325 maint set|show per-command time
326 maint set|show per-command symtab
327 Enable display of per-command gdb resource usage.
329 remove-symbol-file FILENAME
330 remove-symbol-file -a ADDRESS
331 Remove a symbol file added via add-symbol-file. The file to remove
332 can be identified by its filename or by an address that lies within
333 the boundaries of this symbol file in memory.
336 info exceptions REGEXP
337 Display the list of Ada exceptions defined in the program being
338 debugged. If provided, only the exceptions whose names match REGEXP
343 set debug symfile off|on
345 Control display of debugging info regarding reading symbol files and
346 symbol tables within those files
348 set print raw frame-arguments
349 show print raw frame-arguments
350 Set/show whether to print frame arguments in raw mode,
351 disregarding any defined pretty-printers.
353 set remote trace-status-packet
354 show remote trace-status-packet
355 Set/show the use of remote protocol qTStatus packet.
359 Control display of debugging messages related to Nios II targets.
363 Control whether target-assisted range stepping is enabled.
365 set startup-with-shell
366 show startup-with-shell
367 Specifies whether Unix child processes are started via a shell or
372 Use the target memory cache for accesses to the code segment. This
373 improves performance of remote debugging (particularly disassembly).
375 * You can now use a literal value 'unlimited' for options that
376 interpret 0 or -1 as meaning "unlimited". E.g., "set
377 trace-buffer-size unlimited" is now an alias for "set
378 trace-buffer-size -1" and "set height unlimited" is now an alias for
381 * The "set debug symtab-create" debugging option of GDB has been changed to
382 accept a verbosity level. 0 means "off", 1 provides basic debugging
383 output, and values of 2 or greater provides more verbose output.
385 * New command-line options
387 Display the details of GDB configure-time options.
389 * The command 'tsave' can now support new option '-ctf' to save trace
390 buffer in Common Trace Format.
392 * Newly installed $prefix/bin/gcore acts as a shell interface for the
395 * GDB now implements the the C++ 'typeid' operator.
397 * The new convenience variable $_exception holds the exception being
398 thrown or caught at an exception-related catchpoint.
400 * The exception-related catchpoints, like "catch throw", now accept a
401 regular expression which can be used to filter exceptions by type.
403 * The new convenience variable $_exitsignal is automatically set to
404 the terminating signal number when the program being debugged dies
405 due to an uncaught signal.
409 ** All MI commands now accept an optional "--language" option.
410 Support for this feature can be verified by using the "-list-features"
411 command, which should contain "language-option".
413 ** The new command -info-gdb-mi-command allows the user to determine
414 whether a GDB/MI command is supported or not.
416 ** The "^error" result record returned when trying to execute an undefined
417 GDB/MI command now provides a variable named "code" whose content is the
418 "undefined-command" error code. Support for this feature can be verified
419 by using the "-list-features" command, which should contain
420 "undefined-command-error-code".
422 ** The -trace-save MI command can optionally save trace buffer in Common
425 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
427 ** The command -data-list-register-values now accepts an optional
428 "--skip-unavailable" option. When used, only the available registers
431 ** The new command -trace-frame-collected dumps collected variables,
432 computed expressions, tvars, memory and registers in a traceframe.
434 ** The commands -stack-list-locals, -stack-list-arguments and
435 -stack-list-variables now accept an option "--skip-unavailable".
436 When used, only the available locals or arguments are displayed.
438 ** The -exec-run command now accepts an optional "--start" option.
439 When used, the command follows the same semantics as the "start"
440 command, stopping the program's execution at the start of its
441 main subprogram. Support for this feature can be verified using
442 the "-list-features" command, which should contain
443 "exec-run-start-option".
445 ** The new commands -catch-assert and -catch-exceptions insert
446 catchpoints stopping the program when Ada exceptions are raised.
448 ** The new command -info-ada-exceptions provides the equivalent of
449 the new "info exceptions" command.
451 * New system-wide configuration scripts
452 A GDB installation now provides scripts suitable for use as system-wide
453 configuration scripts for the following systems:
457 * GDB now supports target-assigned range stepping with remote targets.
458 This improves the performance of stepping source lines by reducing
459 the number of control packets from/to GDB. See "New remote packets"
462 * GDB now understands the element 'tvar' in the XML traceframe info.
463 It has the id of the collected trace state variables.
465 * On S/390 targets that provide the transactional-execution feature,
466 the program interruption transaction diagnostic block (TDB) is now
467 represented as a number of additional "registers" in GDB.
473 The vCont packet supports a new 'r' action, that tells the remote
474 stub to step through an address range itself, without GDB
475 involvemement at each single-step.
477 qXfer:libraries-svr4:read's annex
478 The previously unused annex of the qXfer:libraries-svr4:read packet
479 is now used to support passing an argument list. The remote stub
480 reports support for this argument list to GDB's qSupported query.
481 The defined arguments are "start" and "prev", used to reduce work
482 necessary for library list updating, resulting in significant
485 * New features in the GDB remote stub, GDBserver
487 ** GDBserver now supports target-assisted range stepping. Currently
488 enabled on x86/x86_64 GNU/Linux targets.
490 ** GDBserver now adds element 'tvar' in the XML in the reply to
491 'qXfer:traceframe-info:read'. It has the id of the collected
492 trace state variables.
494 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
497 * New 'z' formatter for printing and examining memory, this displays the
498 value as hexadecimal zero padded on the left to the size of the type.
500 * GDB can now use Windows x64 unwinding data.
502 * The "set remotebaud" command has been replaced by "set serial baud".
503 Similarly, "show remotebaud" has been replaced by "show serial baud".
504 The "set remotebaud" and "show remotebaud" commands are still available
505 to provide backward compatibility with older versions of GDB.
507 *** Changes in GDB 7.6
509 * Target record has been renamed to record-full.
510 Record/replay is now enabled with the "record full" command.
511 This also affects settings that are associated with full record/replay
512 that have been moved from "set/show record" to "set/show record full":
514 set|show record full insn-number-max
515 set|show record full stop-at-limit
516 set|show record full memory-query
518 * A new record target "record-btrace" has been added. The new target
519 uses hardware support to record the control-flow of a process. It
520 does not support replaying the execution, but it implements the
521 below new commands for investigating the recorded execution log.
522 This new recording method can be enabled using:
526 The "record-btrace" target is only available on Intel Atom processors
527 and requires a Linux kernel 2.6.32 or later.
529 * Two new commands have been added for record/replay to give information
530 about the recorded execution without having to replay the execution.
531 The commands are only supported by "record btrace".
533 record instruction-history prints the execution history at
534 instruction granularity
536 record function-call-history prints the execution history at
539 * New native configurations
541 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
542 FreeBSD/powerpc powerpc*-*-freebsd
543 x86_64/Cygwin x86_64-*-cygwin*
544 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
548 ARM AArch64 aarch64*-*-elf
549 ARM AArch64 GNU/Linux aarch64*-*-linux
550 Lynx 178 PowerPC powerpc-*-lynx*178
551 x86_64/Cygwin x86_64-*-cygwin*
552 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
554 * If the configured location of system.gdbinit file (as given by the
555 --with-system-gdbinit option at configure time) is in the
556 data-directory (as specified by --with-gdb-datadir at configure
557 time) or in one of its subdirectories, then GDB will look for the
558 system-wide init file in the directory specified by the
559 --data-directory command-line option.
561 * New command line options:
563 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
564 other initialization files, unlike -nx which disables all of them.
566 * Removed command line options
568 -epoch This was used by the gdb mode in Epoch, an ancient fork of
571 * The 'ptype' and 'whatis' commands now accept an argument to control
574 * 'info proc' now works on some core files.
578 ** Vectors can be created with gdb.Type.vector.
580 ** Python's atexit.register now works in GDB.
582 ** Types can be pretty-printed via a Python API.
584 ** Python 3 is now supported (in addition to Python 2.4 or later)
586 ** New class gdb.Architecture exposes GDB's internal representation
587 of architecture in the Python API.
589 ** New method Frame.architecture returns the gdb.Architecture object
590 corresponding to the frame's architecture.
592 * New Python-based convenience functions:
594 ** $_memeq(buf1, buf2, length)
595 ** $_streq(str1, str2)
597 ** $_regex(str, regex)
599 * The 'cd' command now defaults to using '~' (the home directory) if not
602 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
603 default for GCC since November 2000.
605 * The command 'forward-search' can now be abbreviated as 'fo'.
607 * The command 'info tracepoints' can now display 'installed on target'
608 or 'not installed on target' for each non-pending location of tracepoint.
610 * New configure options
612 --enable-libmcheck/--disable-libmcheck
613 By default, development versions are built with -lmcheck on hosts
614 that support it, in order to help track memory corruption issues.
615 Release versions, on the other hand, are built without -lmcheck
616 by default. The --enable-libmcheck/--disable-libmcheck configure
617 options allow the user to override that default.
618 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
619 This configure option allows the user to build GDB with
620 libbabeltrace using which GDB can read Common Trace Format data.
622 * New commands (for set/show, see "New options" below)
625 Catch signals. This is similar to "handle", but allows commands and
626 conditions to be attached.
629 List the BFDs known to GDB.
631 python-interactive [command]
633 Start a Python interactive prompt, or evaluate the optional command
634 and print the result of expressions.
637 "py" is a new alias for "python".
639 enable type-printer [name]...
640 disable type-printer [name]...
641 Enable or disable type printers.
645 ** For the Renesas Super-H architecture, the "regs" command has been removed
646 (has been deprecated in GDB 7.5), and "info all-registers" should be used
651 set print type methods (on|off)
652 show print type methods
653 Control whether method declarations are displayed by "ptype".
654 The default is to show them.
656 set print type typedefs (on|off)
657 show print type typedefs
658 Control whether typedef definitions are displayed by "ptype".
659 The default is to show them.
661 set filename-display basename|relative|absolute
662 show filename-display
663 Control the way in which filenames is displayed.
664 The default is "relative", which preserves previous behavior.
666 set trace-buffer-size
667 show trace-buffer-size
668 Request target to change the size of trace buffer.
670 set remote trace-buffer-size-packet auto|on|off
671 show remote trace-buffer-size-packet
672 Control the use of the remote protocol `QTBuffer:size' packet.
676 Control display of debugging messages related to ARM AArch64.
679 set debug coff-pe-read
680 show debug coff-pe-read
681 Control display of debugging messages related to reading of COFF/PE
686 Control display of debugging messages related to Mach-O symbols
689 set debug notification
690 show debug notification
691 Control display of debugging info for async remote notification.
695 ** Command parameter changes are now notified using new async record
696 "=cmd-param-changed".
697 ** Trace frame changes caused by command "tfind" are now notified using
698 new async record "=traceframe-changed".
699 ** The creation, deletion and modification of trace state variables
700 are now notified using new async records "=tsv-created",
701 "=tsv-deleted" and "=tsv-modified".
702 ** The start and stop of process record are now notified using new
703 async record "=record-started" and "=record-stopped".
704 ** Memory changes are now notified using new async record
706 ** The data-disassemble command response will include a "fullname" field
707 containing the absolute file name when source has been requested.
708 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
709 command, to allow pattern filling of memory areas.
710 ** New commands "-catch-load"/"-catch-unload" added for intercepting
711 library load/unload events.
712 ** The response to breakpoint commands and breakpoint async records
713 includes an "installed" field containing a boolean state about each
714 non-pending tracepoint location is whether installed on target or not.
715 ** Output of the "-trace-status" command includes a "trace-file" field
716 containing the name of the trace file being examined. This field is
717 optional, and only present when examining a trace file.
718 ** The "fullname" field is now always present along with the "file" field,
719 even if the file cannot be found by GDB.
721 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
722 You must have the LZMA library available when configuring GDB for this
723 feature to be enabled. For more information, see:
724 http://fedoraproject.org/wiki/Features/MiniDebugInfo
729 Set the size of trace buffer. The remote stub reports support for this
730 packet to gdb's qSupported query.
733 Enable Branch Trace Store (BTS)-based branch tracing for the current
734 thread. The remote stub reports support for this packet to gdb's
738 Disable branch tracing for the current thread. The remote stub reports
739 support for this packet to gdb's qSupported query.
742 Read the traced branches for the current thread. The remote stub
743 reports support for this packet to gdb's qSupported query.
745 *** Changes in GDB 7.5
747 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
748 for more x32 ABI info.
750 * GDB now supports access to MIPS DSP registers on Linux targets.
752 * GDB now supports debugging microMIPS binaries.
754 * The "info os" command on GNU/Linux can now display information on
755 several new classes of objects managed by the operating system:
756 "info os procgroups" lists process groups
757 "info os files" lists file descriptors
758 "info os sockets" lists internet-domain sockets
759 "info os shm" lists shared-memory regions
760 "info os semaphores" lists semaphores
761 "info os msg" lists message queues
762 "info os modules" lists loaded kernel modules
764 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
765 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
766 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
767 options and inspect the probe arguments using the new $_probe_arg family
768 of convenience variables. You can obtain more information about SystemTap
769 in <http://sourceware.org/systemtap/>.
771 * GDB now supports reversible debugging on ARM, it allows you to
772 debug basic ARM and THUMB instructions, and provides
773 record/replay support.
775 * The option "symbol-reloading" has been deleted as it is no longer used.
779 ** GDB commands implemented in Python can now be put in command class
782 ** The "maint set python print-stack on|off" is now deleted.
784 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
785 apply "flag enum"-style pretty-printing to any enum.
787 ** gdb.lookup_symbol can now work when there is no current frame.
789 ** gdb.Symbol now has a 'line' attribute, holding the line number in
790 the source at which the symbol was defined.
792 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
793 method 'value'. The former indicates whether the symbol needs a
794 frame in order to compute its value, and the latter computes the
797 ** A new method 'referenced_value' on gdb.Value objects which can
798 dereference pointer as well as C++ reference values.
800 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
801 which return the global and static blocks (as gdb.Block objects),
802 of the underlying symbol table, respectively.
804 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
805 object associated with a PC value.
807 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
808 of the address range occupied by code for the current source line.
810 * Go language support.
811 GDB now supports debugging programs written in the Go programming
814 * GDBserver now supports stdio connections.
815 E.g. (gdb) target remote | ssh myhost gdbserver - hello
817 * The binary "gdbtui" can no longer be built or installed.
818 Use "gdb -tui" instead.
820 * GDB will now print "flag" enums specially. A flag enum is one where
821 all the enumerator values have no bits in common when pairwise
822 "and"ed. When printing a value whose type is a flag enum, GDB will
823 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
824 (gdb) print (enum E) 3
827 * The filename part of a linespec will now match trailing components
828 of a source file name. For example, "break gcc/expr.c:1000" will
829 now set a breakpoint in build/gcc/expr.c, but not
832 * The "info proc" and "generate-core-file" commands will now also
833 work on remote targets connected to GDBserver on Linux.
835 * The command "info catch" has been removed. It has been disabled
838 * The "catch exception" and "catch assert" commands now accept
839 a condition at the end of the command, much like the "break"
840 command does. For instance:
842 (gdb) catch exception Constraint_Error if Barrier = True
844 Previously, it was possible to add a condition to such catchpoints,
845 but it had to be done as a second step, after the catchpoint had been
846 created, using the "condition" command.
848 * The "info static-tracepoint-marker" command will now also work on
849 native Linux targets with in-process agent.
851 * GDB can now set breakpoints on inlined functions.
853 * The .gdb_index section has been updated to include symbols for
854 inlined functions. GDB will ignore older .gdb_index sections by
855 default, which could cause symbol files to be loaded more slowly
856 until their .gdb_index sections can be recreated. The new command
857 "set use-deprecated-index-sections on" will cause GDB to use any older
858 .gdb_index sections it finds. This will restore performance, but the
859 ability to set breakpoints on inlined functions will be lost in symbol
860 files with older .gdb_index sections.
862 The .gdb_index section has also been updated to record more information
863 about each symbol. This speeds up the "info variables", "info functions"
864 and "info types" commands when used with programs having the .gdb_index
865 section, as well as speeding up debugging with shared libraries using
866 the .gdb_index section.
868 * Ada support for GDB/MI Variable Objects has been added.
870 * GDB can now support 'breakpoint always-inserted mode' in 'record'
875 ** New command -info-os is the MI equivalent of "info os".
877 ** Output logs ("set logging" and related) now include MI output.
881 ** "set use-deprecated-index-sections on|off"
882 "show use-deprecated-index-sections on|off"
883 Controls the use of deprecated .gdb_index sections.
885 ** "catch load" and "catch unload" can be used to stop when a shared
886 library is loaded or unloaded, respectively.
888 ** "enable count" can be used to auto-disable a breakpoint after
891 ** "info vtbl" can be used to show the virtual method tables for
892 C++ and Java objects.
894 ** "explore" and its sub commands "explore value" and "explore type"
895 can be used to recursively explore values and types of
896 expressions. These commands are available only if GDB is
897 configured with '--with-python'.
899 ** "info auto-load" shows status of all kinds of auto-loaded files,
900 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
901 sequences of commands files, "info auto-load python-scripts"
902 shows status of auto-loading Python script files,
903 "info auto-load local-gdbinit" shows status of loading init file
904 (.gdbinit) from current directory and "info auto-load libthread-db" shows
905 status of inferior specific thread debugging shared library loading.
907 ** "info auto-load-scripts", "set auto-load-scripts on|off"
908 and "show auto-load-scripts" commands have been deprecated, use their
909 "info auto-load python-scripts", "set auto-load python-scripts on|off"
910 and "show auto-load python-scripts" counterparts instead.
912 ** "dprintf location,format,args..." creates a dynamic printf, which
913 is basically a breakpoint that does a printf and immediately
914 resumes your program's execution, so it is like a printf that you
915 can insert dynamically at runtime instead of at compiletime.
917 ** "set print symbol"
919 Controls whether GDB attempts to display the symbol, if any,
920 corresponding to addresses it prints. This defaults to "on", but
921 you can set it to "off" to restore GDB's previous behavior.
923 * Deprecated commands
925 ** For the Renesas Super-H architecture, the "regs" command has been
926 deprecated, and "info all-registers" should be used instead.
930 Renesas RL78 rl78-*-elf
931 HP OpenVMS ia64 ia64-hp-openvms*
933 * GDBserver supports evaluation of breakpoint conditions. When
934 support is advertised by GDBserver, GDB may be told to send the
935 breakpoint conditions in bytecode form to GDBserver. GDBserver
936 will only report the breakpoint trigger to GDB when its condition
942 show mips compression
943 Select the compressed ISA encoding used in functions that have no symbol
944 information available. The encoding can be set to either of:
947 and is updated automatically from ELF file flags if available.
949 set breakpoint condition-evaluation
950 show breakpoint condition-evaluation
951 Control whether breakpoint conditions are evaluated by GDB ("host") or by
952 GDBserver ("target"). Default option "auto" chooses the most efficient
954 This option can improve debugger efficiency depending on the speed of the
958 Disable auto-loading globally.
961 Show auto-loading setting of all kinds of auto-loaded files.
963 set auto-load gdb-scripts on|off
964 show auto-load gdb-scripts
965 Control auto-loading of GDB canned sequences of commands files.
967 set auto-load python-scripts on|off
968 show auto-load python-scripts
969 Control auto-loading of Python script files.
971 set auto-load local-gdbinit on|off
972 show auto-load local-gdbinit
973 Control loading of init file (.gdbinit) from current directory.
975 set auto-load libthread-db on|off
976 show auto-load libthread-db
977 Control auto-loading of inferior specific thread debugging shared library.
979 set auto-load scripts-directory <dir1>[:<dir2>...]
980 show auto-load scripts-directory
981 Set a list of directories from which to load auto-loaded scripts.
982 Automatically loaded Python scripts and GDB scripts are located in one
983 of the directories listed by this option.
984 The delimiter (':' above) may differ according to the host platform.
986 set auto-load safe-path <dir1>[:<dir2>...]
987 show auto-load safe-path
988 Set a list of directories from which it is safe to auto-load files.
989 The delimiter (':' above) may differ according to the host platform.
991 set debug auto-load on|off
993 Control display of debugging info for auto-loading the files above.
995 set dprintf-style gdb|call|agent
997 Control the way in which a dynamic printf is performed; "gdb"
998 requests a GDB printf command, while "call" causes dprintf to call a
999 function in the inferior. "agent" requests that the target agent
1000 (such as GDBserver) do the printing.
1002 set dprintf-function <expr>
1003 show dprintf-function
1004 set dprintf-channel <expr>
1005 show dprintf-channel
1006 Set the function and optional first argument to the call when using
1007 the "call" style of dynamic printf.
1009 set disconnected-dprintf on|off
1010 show disconnected-dprintf
1011 Control whether agent-style dynamic printfs continue to be in effect
1012 after GDB disconnects.
1014 * New configure options
1016 --with-auto-load-dir
1017 Configure default value for the 'set auto-load scripts-directory'
1018 setting above. It defaults to '$debugdir:$datadir/auto-load',
1019 $debugdir representing global debugging info directories (available
1020 via 'show debug-file-directory') and $datadir representing GDB's data
1021 directory (available via 'show data-directory').
1023 --with-auto-load-safe-path
1024 Configure default value for the 'set auto-load safe-path' setting
1025 above. It defaults to the --with-auto-load-dir setting.
1027 --without-auto-load-safe-path
1028 Set 'set auto-load safe-path' to '/', effectively disabling this
1031 * New remote packets
1033 z0/z1 conditional breakpoints extension
1035 The z0/z1 breakpoint insertion packets have been extended to carry
1036 a list of conditional expressions over to the remote stub depending on the
1037 condition evaluation mode. The use of this extension can be controlled
1038 via the "set remote conditional-breakpoints-packet" command.
1042 Specify the signals which the remote stub may pass to the debugged
1043 program without GDB involvement.
1045 * New command line options
1047 --init-command=FILE, -ix Like --command, -x but execute it
1048 before loading inferior.
1049 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1050 execute it before loading inferior.
1052 *** Changes in GDB 7.4
1054 * GDB now handles ambiguous linespecs more consistently; the existing
1055 FILE:LINE support has been expanded to other types of linespecs. A
1056 breakpoint will now be set on all matching locations in all
1057 inferiors, and locations will be added or removed according to
1060 * GDB now allows you to skip uninteresting functions and files when
1061 stepping with the "skip function" and "skip file" commands.
1063 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1064 and "show remote hardware-watchpoint-length-limit". These allows to
1065 set or show the maximum length limit (in bytes) of a remote
1066 target hardware watchpoint.
1068 This allows e.g. to use "unlimited" hardware watchpoints with the
1069 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1070 watchpoints are slower than real hardware watchpoints but are
1071 significantly faster than gdb software watchpoints.
1075 ** The register_pretty_printer function in module gdb.printing now takes
1076 an optional `replace' argument. If True, the new printer replaces any
1079 ** The "maint set python print-stack on|off" command has been
1080 deprecated and will be deleted in GDB 7.5.
1081 A new command: "set python print-stack none|full|message" has
1082 replaced it. Additionally, the default for "print-stack" is
1083 now "message", which just prints the error message without
1086 ** A prompt substitution hook (prompt_hook) is now available to the
1089 ** A new Python module, gdb.prompt has been added to the GDB Python
1090 modules library. This module provides functionality for
1091 escape sequences in prompts (used by set/show
1092 extended-prompt). These escape sequences are replaced by their
1093 corresponding value.
1095 ** Python commands and convenience-functions located in
1096 'data-directory'/python/gdb/command and
1097 'data-directory'/python/gdb/function are now automatically loaded
1100 ** Blocks now provide four new attributes. global_block and
1101 static_block will return the global and static blocks
1102 respectively. is_static and is_global are boolean attributes
1103 that indicate if the block is one of those two types.
1105 ** Symbols now provide the "type" attribute, the type of the symbol.
1107 ** The "gdb.breakpoint" function has been deprecated in favor of
1110 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1111 of a function. This class is based on the "finish" command
1112 available in the CLI.
1114 ** Type objects for struct and union types now allow access to
1115 the fields using standard Python dictionary (mapping) methods.
1116 For example, "some_type['myfield']" now works, as does
1117 "some_type.items()".
1119 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1122 ** A new function, "deep_items" has been added to the gdb.types
1123 module in the GDB Python modules library. This function returns
1124 an iterator over the fields of a struct or union type. Unlike
1125 the standard Python "iteritems" method, it will recursively traverse
1126 any anonymous fields.
1130 ** "*stopped" events can report several new "reason"s, such as
1133 ** Breakpoint changes are now notified using new async records, like
1134 "=breakpoint-modified".
1136 ** New command -ada-task-info.
1138 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1139 $sdir specifies the default system locations of shared libraries.
1140 $pdir specifies the directory where the libpthread used by the application
1143 GDB no longer looks in $sdir and $pdir after it has searched the directories
1144 mentioned in libthread-db-search-path. If you want to search those
1145 directories, they must be specified in libthread-db-search-path.
1146 The default value of libthread-db-search-path on GNU/Linux and Solaris
1147 systems is now "$sdir:$pdir".
1149 $pdir is not supported by gdbserver, it is currently ignored.
1150 $sdir is supported by gdbserver.
1152 * New configure option --with-iconv-bin.
1153 When using the internationalization support like the one in the GNU C
1154 library, GDB will invoke the "iconv" program to get a list of supported
1155 character sets. If this program lives in a non-standard location, one can
1156 use this option to specify where to find it.
1158 * When natively debugging programs on PowerPC BookE processors running
1159 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1160 watchpoints, which specify a mask in addition to an address to watch.
1161 The mask specifies that some bits of an address (the bits which are
1162 reset in the mask) should be ignored when matching the address accessed
1163 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1164 section in the user manual for more details.
1166 * The new option --once causes GDBserver to stop listening for connections once
1167 the first connection is made. The listening port used by GDBserver will
1168 become available after that.
1170 * New commands "info macros" and "alias" have been added.
1172 * New function parameters suffix @entry specifies value of function parameter
1173 at the time the function got called. Entry values are available only since
1179 "!" is now an alias of the "shell" command.
1180 Note that no space is needed between "!" and SHELL COMMAND.
1184 watch EXPRESSION mask MASK_VALUE
1185 The watch command now supports the mask argument which allows creation
1186 of masked watchpoints, if the current architecture supports this feature.
1188 info auto-load-scripts [REGEXP]
1189 This command was formerly named "maintenance print section-scripts".
1190 It is now generally useful and is no longer a maintenance-only command.
1192 info macro [-all] [--] MACRO
1193 The info macro command has new options `-all' and `--'. The first for
1194 printing all definitions of a macro. The second for explicitly specifying
1195 the end of arguments and the beginning of the macro name in case the macro
1196 name starts with a hyphen.
1198 collect[/s] EXPRESSIONS
1199 The tracepoint collect command now takes an optional modifier "/s"
1200 that directs it to dereference pointer-to-character types and
1201 collect the bytes of memory up to a zero byte. The behavior is
1202 similar to what you see when you use the regular print command on a
1203 string. An optional integer following the "/s" sets a bound on the
1204 number of bytes that will be collected.
1207 The trace start command now interprets any supplied arguments as a
1208 note to be recorded with the trace run, with an effect similar to
1209 setting the variable trace-notes.
1212 The trace stop command now interprets any arguments as a note to be
1213 mentioned along with the tstatus report that the trace was stopped
1214 with a command. The effect is similar to setting the variable
1217 * Tracepoints can now be enabled and disabled at any time after a trace
1218 experiment has been started using the standard "enable" and "disable"
1219 commands. It is now possible to start a trace experiment with no enabled
1220 tracepoints; GDB will display a warning, but will allow the experiment to
1221 begin, assuming that tracepoints will be enabled as needed while the trace
1224 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1225 locations with 4-byte instructions, when they were previously
1226 limited to locations with instructions of 5 bytes or longer.
1230 set debug dwarf2-read
1231 show debug dwarf2-read
1232 Turns on or off display of debugging messages related to reading
1233 DWARF debug info. The default is off.
1235 set debug symtab-create
1236 show debug symtab-create
1237 Turns on or off display of debugging messages related to symbol table
1238 creation. The default is off.
1241 show extended-prompt
1242 Set the GDB prompt, and allow escape sequences to be inserted to
1243 display miscellaneous information (see 'help set extended-prompt'
1244 for the list of sequences). This prompt (and any information
1245 accessed through the escape sequences) is updated every time the
1246 prompt is displayed.
1248 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1249 show print entry-values
1250 Set printing of frame argument values at function entry. In some cases
1251 GDB can determine the value of function argument which was passed by the
1252 function caller, even if the value was modified inside the called function.
1254 set debug entry-values
1255 show debug entry-values
1256 Control display of debugging info for determining frame argument values at
1257 function entry and virtual tail call frames.
1259 set basenames-may-differ
1260 show basenames-may-differ
1261 Set whether a source file may have multiple base names.
1262 (A "base name" is the name of a file with the directory part removed.
1263 Example: The base name of "/home/user/hello.c" is "hello.c".)
1264 If set, GDB will canonicalize file names (e.g., expand symlinks)
1265 before comparing them. Canonicalization is an expensive operation,
1266 but it allows the same file be known by more than one base name.
1267 If not set (the default), all source files are assumed to have just
1268 one base name, and gdb will do file name comparisons more efficiently.
1274 Set a user name and notes for the current and any future trace runs.
1275 This is useful for long-running and/or disconnected traces, to
1276 inform others (or yourself) as to who is running the trace, supply
1277 contact information, or otherwise explain what is going on.
1279 set trace-stop-notes
1280 show trace-stop-notes
1281 Set a note attached to the trace run, that is displayed when the
1282 trace has been stopped by a tstop command. This is useful for
1283 instance as an explanation, if you are stopping a trace run that was
1284 started by someone else.
1286 * New remote packets
1290 Dynamically enable a tracepoint in a started trace experiment.
1294 Dynamically disable a tracepoint in a started trace experiment.
1298 Set the user and notes of the trace run.
1302 Query the current status of a tracepoint.
1306 Query the minimum length of instruction at which a fast tracepoint may
1309 * Dcache size (number of lines) and line-size are now runtime-configurable
1310 via "set dcache line" and "set dcache line-size" commands.
1314 Texas Instruments TMS320C6x tic6x-*-*
1318 Renesas RL78 rl78-*-elf
1320 *** Changes in GDB 7.3.1
1322 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1324 *** Changes in GDB 7.3
1326 * GDB has a new command: "thread find [REGEXP]".
1327 It finds the thread id whose name, target id, or thread extra info
1328 matches the given regular expression.
1330 * The "catch syscall" command now works on mips*-linux* targets.
1332 * The -data-disassemble MI command now supports modes 2 and 3 for
1333 dumping the instruction opcodes.
1335 * New command line options
1337 -data-directory DIR Specify DIR as the "data-directory".
1338 This is mostly for testing purposes.
1340 * The "maint set python auto-load on|off" command has been renamed to
1341 "set auto-load-scripts on|off".
1343 * GDB has a new command: "set directories".
1344 It is like the "dir" command except that it replaces the
1345 source path list instead of augmenting it.
1347 * GDB now understands thread names.
1349 On GNU/Linux, "info threads" will display the thread name as set by
1350 prctl or pthread_setname_np.
1352 There is also a new command, "thread name", which can be used to
1353 assign a name internally for GDB to display.
1356 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1357 has been integrated into GDB.
1361 ** The function gdb.Write now accepts an optional keyword 'stream'.
1362 This keyword, when provided, will direct the output to either
1363 stdout, stderr, or GDB's logging output.
1365 ** Parameters can now be be sub-classed in Python, and in particular
1366 you may implement the get_set_doc and get_show_doc functions.
1367 This improves how Parameter set/show documentation is processed
1368 and allows for more dynamic content.
1370 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1371 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1372 have an is_valid method.
1374 ** Breakpoints can now be sub-classed in Python, and in particular
1375 you may implement a 'stop' function that is executed each time
1376 the inferior reaches that breakpoint.
1378 ** New function gdb.lookup_global_symbol looks up a global symbol.
1380 ** GDB values in Python are now callable if the value represents a
1381 function. For example, if 'some_value' represents a function that
1382 takes two integer parameters and returns a value, you can call
1383 that function like so:
1385 result = some_value (10,20)
1387 ** Module gdb.types has been added.
1388 It contains a collection of utilities for working with gdb.Types objects:
1389 get_basic_type, has_field, make_enum_dict.
1391 ** Module gdb.printing has been added.
1392 It contains utilities for writing and registering pretty-printers.
1393 New classes: PrettyPrinter, SubPrettyPrinter,
1394 RegexpCollectionPrettyPrinter.
1395 New function: register_pretty_printer.
1397 ** New commands "info pretty-printers", "enable pretty-printer" and
1398 "disable pretty-printer" have been added.
1400 ** gdb.parameter("directories") is now available.
1402 ** New function gdb.newest_frame returns the newest frame in the
1405 ** The gdb.InferiorThread class has a new "name" attribute. This
1406 holds the thread's name.
1408 ** Python Support for Inferior events.
1409 Python scripts can add observers to be notified of events
1410 occurring in the process being debugged.
1411 The following events are currently supported:
1412 - gdb.events.cont Continue event.
1413 - gdb.events.exited Inferior exited event.
1414 - gdb.events.stop Signal received, and Breakpoint hit events.
1418 ** GDB now puts template parameters in scope when debugging in an
1419 instantiation. For example, if you have:
1421 template<int X> int func (void) { return X; }
1423 then if you step into func<5>, "print X" will show "5". This
1424 feature requires proper debuginfo support from the compiler; it
1425 was added to GCC 4.5.
1427 ** The motion commands "next", "finish", "until", and "advance" now
1428 work better when exceptions are thrown. In particular, GDB will
1429 no longer lose control of the inferior; instead, the GDB will
1430 stop the inferior at the point at which the exception is caught.
1431 This functionality requires a change in the exception handling
1432 code that was introduced in GCC 4.5.
1434 * GDB now follows GCC's rules on accessing volatile objects when
1435 reading or writing target state during expression evaluation.
1436 One notable difference to prior behavior is that "print x = 0"
1437 no longer generates a read of x; the value of the assignment is
1438 now always taken directly from the value being assigned.
1440 * GDB now has some support for using labels in the program's source in
1441 linespecs. For instance, you can use "advance label" to continue
1442 execution to a label.
1444 * GDB now has support for reading and writing a new .gdb_index
1445 section. This section holds a fast index of DWARF debugging
1446 information and can be used to greatly speed up GDB startup and
1447 operation. See the documentation for `save gdb-index' for details.
1449 * The "watch" command now accepts an optional "-location" argument.
1450 When used, this causes GDB to watch the memory referred to by the
1451 expression. Such a watchpoint is never deleted due to it going out
1454 * GDB now supports thread debugging of core dumps on GNU/Linux.
1456 GDB now activates thread debugging using the libthread_db library
1457 when debugging GNU/Linux core dumps, similarly to when debugging
1458 live processes. As a result, when debugging a core dump file, GDB
1459 is now able to display pthread_t ids of threads. For example, "info
1460 threads" shows the same output as when debugging the process when it
1461 was live. In earlier releases, you'd see something like this:
1464 * 1 LWP 6780 main () at main.c:10
1466 While now you see this:
1469 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1471 It is also now possible to inspect TLS variables when debugging core
1474 When debugging a core dump generated on a machine other than the one
1475 used to run GDB, you may need to point GDB at the correct
1476 libthread_db library with the "set libthread-db-search-path"
1477 command. See the user manual for more details on this command.
1479 * When natively debugging programs on PowerPC BookE processors running
1480 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1481 which stop execution of the inferior whenever it executes an instruction
1482 at any address within the specified range. See the "PowerPC Embedded"
1483 section in the user manual for more details.
1485 * New features in the GDB remote stub, GDBserver
1487 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1488 and i686 LynxOS (version 5.x).
1490 ** GDBserver is now supported on Blackfin Linux.
1492 * New native configurations
1494 ia64 HP-UX ia64-*-hpux*
1498 Analog Devices, Inc. Blackfin Processor bfin-*
1500 * Ada task switching is now supported on sparc-elf targets when
1501 debugging a program using the Ravenscar Profile. For more information,
1502 see the "Tasking Support when using the Ravenscar Profile" section
1503 in the GDB user manual.
1505 * Guile support was removed.
1507 * New features in the GNU simulator
1509 ** The --map-info flag lists all known core mappings.
1511 ** CFI flashes may be simulated via the "cfi" device.
1513 *** Changes in GDB 7.2
1515 * Shared library support for remote targets by default
1517 When GDB is configured for a generic, non-OS specific target, like
1518 for example, --target=arm-eabi or one of the many *-*-elf targets,
1519 GDB now queries remote stubs for loaded shared libraries using the
1520 `qXfer:libraries:read' packet. Previously, shared library support
1521 was always disabled for such configurations.
1525 ** Argument Dependent Lookup (ADL)
1527 In C++ ADL lookup directs function search to the namespaces of its
1528 arguments even if the namespace has not been imported.
1538 Here the compiler will search for `foo' in the namespace of 'b'
1539 and find A::foo. GDB now supports this. This construct is commonly
1540 used in the Standard Template Library for operators.
1542 ** Improved User Defined Operator Support
1544 In addition to member operators, GDB now supports lookup of operators
1545 defined in a namespace and imported with a `using' directive, operators
1546 defined in the global scope, operators imported implicitly from an
1547 anonymous namespace, and the ADL operators mentioned in the previous
1549 GDB now also supports proper overload resolution for all the previously
1550 mentioned flavors of operators.
1552 ** static const class members
1554 Printing of static const class members that are initialized in the
1555 class definition has been fixed.
1557 * Windows Thread Information Block access.
1559 On Windows targets, GDB now supports displaying the Windows Thread
1560 Information Block (TIB) structure. This structure is visible either
1561 by using the new command `info w32 thread-information-block' or, by
1562 dereferencing the new convenience variable named `$_tlb', a
1563 thread-specific pointer to the TIB. This feature is also supported
1564 when remote debugging using GDBserver.
1566 * Static tracepoints
1568 Static tracepoints are calls in the user program into a tracing
1569 library. One such library is a port of the LTTng kernel tracer to
1570 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1571 When debugging with GDBserver, GDB now supports combining the GDB
1572 tracepoint machinery with such libraries. For example: the user can
1573 use GDB to probe a static tracepoint marker (a call from the user
1574 program into the tracing library) with the new "strace" command (see
1575 "New commands" below). This creates a "static tracepoint" in the
1576 breakpoint list, that can be manipulated with the same feature set
1577 as fast and regular tracepoints. E.g., collect registers, local and
1578 global variables, collect trace state variables, and define
1579 tracepoint conditions. In addition, the user can collect extra
1580 static tracepoint marker specific data, by collecting the new
1581 $_sdata internal variable. When analyzing the trace buffer, you can
1582 inspect $_sdata like any other variable available to GDB. For more
1583 information, see the "Tracepoints" chapter in GDB user manual. New
1584 remote packets have been defined to support static tracepoints, see
1585 the "New remote packets" section below.
1587 * Better reconstruction of tracepoints after disconnected tracing
1589 GDB will attempt to download the original source form of tracepoint
1590 definitions when starting a trace run, and then will upload these
1591 upon reconnection to the target, resulting in a more accurate
1592 reconstruction of the tracepoints that are in use on the target.
1596 You can now exercise direct control over the ways that GDB can
1597 affect your program. For instance, you can disallow the setting of
1598 breakpoints, so that the program can run continuously (assuming
1599 non-stop mode). In addition, the "observer" variable is available
1600 to switch all of the different controls; in observer mode, GDB
1601 cannot affect the target's behavior at all, which is useful for
1602 tasks like diagnosing live systems in the field.
1604 * The new convenience variable $_thread holds the number of the
1607 * New remote packets
1611 Return the address of the Windows Thread Information Block of a given thread.
1615 In response to several of the tracepoint packets, the target may now
1616 also respond with a number of intermediate `qRelocInsn' request
1617 packets before the final result packet, to have GDB handle
1618 relocating an instruction to execute at a different address. This
1619 is particularly useful for stubs that support fast tracepoints. GDB
1620 reports support for this feature in the qSupported packet.
1624 List static tracepoint markers in the target program.
1628 List static tracepoint markers at a given address in the target
1631 qXfer:statictrace:read
1633 Read the static trace data collected (by a `collect $_sdata'
1634 tracepoint action). The remote stub reports support for this packet
1635 to gdb's qSupported query.
1639 Send the current settings of GDB's permission flags.
1643 Send part of the source (textual) form of a tracepoint definition,
1644 which includes location, conditional, and action list.
1646 * The source command now accepts a -s option to force searching for the
1647 script in the source search path even if the script name specifies
1650 * New features in the GDB remote stub, GDBserver
1652 - GDBserver now support tracepoints (including fast tracepoints, and
1653 static tracepoints). The feature is currently supported by the
1654 i386-linux and amd64-linux builds. See the "Tracepoints support
1655 in gdbserver" section in the manual for more information.
1657 GDBserver JIT compiles the tracepoint's conditional agent
1658 expression bytecode into native code whenever possible for low
1659 overhead dynamic tracepoints conditionals. For such tracepoints,
1660 an expression that examines program state is evaluated when the
1661 tracepoint is reached, in order to determine whether to capture
1662 trace data. If the condition is simple and false, processing the
1663 tracepoint finishes very quickly and no data is gathered.
1665 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1666 for static tracepoints support.
1668 - GDBserver now supports x86_64 Windows 64-bit debugging.
1670 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1671 it understands register description.
1673 * The --batch flag now disables pagination and queries.
1675 * X86 general purpose registers
1677 GDB now supports reading/writing byte, word and double-word x86
1678 general purpose registers directly. This means you can use, say,
1679 $ah or $ax to refer, respectively, to the byte register AH and
1680 16-bit word register AX that are actually portions of the 32-bit
1681 register EAX or 64-bit register RAX.
1683 * The `commands' command now accepts a range of breakpoints to modify.
1684 A plain `commands' following a command that creates multiple
1685 breakpoints affects all the breakpoints set by that command. This
1686 applies to breakpoints set by `rbreak', and also applies when a
1687 single `break' command creates multiple breakpoints (e.g.,
1688 breakpoints on overloaded c++ functions).
1690 * The `rbreak' command now accepts a filename specification as part of
1691 its argument, limiting the functions selected by the regex to those
1692 in the specified file.
1694 * Support for remote debugging Windows and SymbianOS shared libraries
1695 from Unix hosts has been improved. Non Windows GDB builds now can
1696 understand target reported file names that follow MS-DOS based file
1697 system semantics, such as file names that include drive letters and
1698 use the backslash character as directory separator. This makes it
1699 possible to transparently use the "set sysroot" and "set
1700 solib-search-path" on Unix hosts to point as host copies of the
1701 target's shared libraries. See the new command "set
1702 target-file-system-kind" described below, and the "Commands to
1703 specify files" section in the user manual for more information.
1707 eval template, expressions...
1708 Convert the values of one or more expressions under the control
1709 of the string template to a command line, and call it.
1711 set target-file-system-kind unix|dos-based|auto
1712 show target-file-system-kind
1713 Set or show the assumed file system kind for target reported file
1716 save breakpoints <filename>
1717 Save all current breakpoint definitions to a file suitable for use
1718 in a later debugging session. To read the saved breakpoint
1719 definitions, use the `source' command.
1721 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1724 info static-tracepoint-markers
1725 Display information about static tracepoint markers in the target.
1727 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1728 Define a static tracepoint by probing a marker at the given
1729 function, line, address, or marker ID.
1733 Enable and disable observer mode.
1735 set may-write-registers on|off
1736 set may-write-memory on|off
1737 set may-insert-breakpoints on|off
1738 set may-insert-tracepoints on|off
1739 set may-insert-fast-tracepoints on|off
1740 set may-interrupt on|off
1741 Set individual permissions for GDB effects on the target. Note that
1742 some of these settings can have undesirable or surprising
1743 consequences, particularly when changed in the middle of a session.
1744 For instance, disabling the writing of memory can prevent
1745 breakpoints from being inserted, cause single-stepping to fail, or
1746 even crash your program, if you disable after breakpoints have been
1747 inserted. However, GDB should not crash.
1749 set record memory-query on|off
1750 show record memory-query
1751 Control whether to stop the inferior if memory changes caused
1752 by an instruction cannot be recorded.
1757 The disassemble command now supports "start,+length" form of two arguments.
1761 ** GDB now provides a new directory location, called the python directory,
1762 where Python scripts written for GDB can be installed. The location
1763 of that directory is <data-directory>/python, where <data-directory>
1764 is the GDB data directory. For more details, see section `Scripting
1765 GDB using Python' in the manual.
1767 ** The GDB Python API now has access to breakpoints, symbols, symbol
1768 tables, program spaces, inferiors, threads and frame's code blocks.
1769 Additionally, GDB Parameters can now be created from the API, and
1770 manipulated via set/show in the CLI.
1772 ** New functions gdb.target_charset, gdb.target_wide_charset,
1773 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1775 ** New exception gdb.GdbError.
1777 ** Pretty-printers are now also looked up in the current program space.
1779 ** Pretty-printers can now be individually enabled and disabled.
1781 ** GDB now looks for names of Python scripts to auto-load in a
1782 special section named `.debug_gdb_scripts', in addition to looking
1783 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1785 * Tracepoint actions were unified with breakpoint commands. In particular,
1786 there are no longer differences in "info break" output for breakpoints and
1787 tracepoints and the "commands" command can be used for both tracepoints and
1788 regular breakpoints.
1792 ARM Symbian arm*-*-symbianelf*
1794 * D language support.
1795 GDB now supports debugging programs written in the D programming
1798 * GDB now supports the extended ptrace interface for PowerPC which is
1799 available since Linux kernel version 2.6.34. This automatically enables
1800 any hardware breakpoints and additional hardware watchpoints available in
1801 the processor. The old ptrace interface exposes just one hardware
1802 watchpoint and no hardware breakpoints.
1804 * GDB is now able to use the Data Value Compare (DVC) register available on
1805 embedded PowerPC processors to implement in hardware simple watchpoint
1806 conditions of the form:
1808 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1810 This works in native GDB running on Linux kernels with the extended ptrace
1811 interface mentioned above.
1813 *** Changes in GDB 7.1
1817 ** Namespace Support
1819 GDB now supports importing of namespaces in C++. This enables the
1820 user to inspect variables from imported namespaces. Support for
1821 namepace aliasing has also been added. So, if a namespace is
1822 aliased in the current scope (e.g. namepace C=A; ) the user can
1823 print variables using the alias (e.g. (gdb) print C::x).
1827 All known bugs relating to the printing of virtual base class were
1828 fixed. It is now possible to call overloaded static methods using a
1833 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1834 and reinterpret_cast<> are now handled by the C++ expression parser.
1838 Xilinx MicroBlaze microblaze-*-*
1843 Xilinx MicroBlaze microblaze
1846 * Multi-program debugging.
1848 GDB now has support for multi-program (a.k.a. multi-executable or
1849 multi-exec) debugging. This allows for debugging multiple inferiors
1850 simultaneously each running a different program under the same GDB
1851 session. See "Debugging Multiple Inferiors and Programs" in the
1852 manual for more information. This implied some user visible changes
1853 in the multi-inferior support. For example, "info inferiors" now
1854 lists inferiors that are not running yet or that have exited
1855 already. See also "New commands" and "New options" below.
1857 * New tracing features
1859 GDB's tracepoint facility now includes several new features:
1861 ** Trace state variables
1863 GDB tracepoints now include support for trace state variables, which
1864 are variables managed by the target agent during a tracing
1865 experiment. They are useful for tracepoints that trigger each
1866 other, so for instance one tracepoint can count hits in a variable,
1867 and then a second tracepoint has a condition that is true when the
1868 count reaches a particular value. Trace state variables share the
1869 $-syntax of GDB convenience variables, and can appear in both
1870 tracepoint actions and condition expressions. Use the "tvariable"
1871 command to create, and "info tvariables" to view; see "Trace State
1872 Variables" in the manual for more detail.
1876 GDB now includes an option for defining fast tracepoints, which
1877 targets may implement more efficiently, such as by installing a jump
1878 into the target agent rather than a trap instruction. The resulting
1879 speedup can be by two orders of magnitude or more, although the
1880 tradeoff is that some program locations on some target architectures
1881 might not allow fast tracepoint installation, for instance if the
1882 instruction to be replaced is shorter than the jump. To request a
1883 fast tracepoint, use the "ftrace" command, with syntax identical to
1884 the regular trace command.
1886 ** Disconnected tracing
1888 It is now possible to detach GDB from the target while it is running
1889 a trace experiment, then reconnect later to see how the experiment
1890 is going. In addition, a new variable disconnected-tracing lets you
1891 tell the target agent whether to continue running a trace if the
1892 connection is lost unexpectedly.
1896 GDB now has the ability to save the trace buffer into a file, and
1897 then use that file as a target, similarly to you can do with
1898 corefiles. You can select trace frames, print data that was
1899 collected in them, and use tstatus to display the state of the
1900 tracing run at the moment that it was saved. To create a trace
1901 file, use "tsave <filename>", and to use it, do "target tfile
1904 ** Circular trace buffer
1906 You can ask the target agent to handle the trace buffer as a
1907 circular buffer, discarding the oldest trace frames to make room for
1908 newer ones, by setting circular-trace-buffer to on. This feature may
1909 not be available for all target agents.
1914 The disassemble command, when invoked with two arguments, now requires
1915 the arguments to be comma-separated.
1918 The info variables command now displays variable definitions. Files
1919 which only declare a variable are not shown.
1922 The source command is now capable of sourcing Python scripts.
1923 This feature is dependent on the debugger being build with Python
1926 Related to this enhancement is also the introduction of a new command
1927 "set script-extension" (see below).
1929 * New commands (for set/show, see "New options" below)
1931 record save [<FILENAME>]
1932 Save a file (in core file format) containing the process record
1933 execution log for replay debugging at a later time.
1935 record restore <FILENAME>
1936 Restore the process record execution log that was saved at an
1937 earlier time, for replay debugging.
1939 add-inferior [-copies <N>] [-exec <FILENAME>]
1942 clone-inferior [-copies <N>] [ID]
1943 Make a new inferior ready to execute the same program another
1944 inferior has loaded.
1949 maint info program-spaces
1950 List the program spaces loaded into GDB.
1952 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1953 show remote interrupt-sequence
1954 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1955 as the sequence to the remote target in order to interrupt the execution.
1956 Ctrl-C is a default. Some system prefers BREAK which is high level of
1957 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1958 Magic SysRq g. It is BREAK signal and character 'g'.
1960 set remote interrupt-on-connect [on | off]
1961 show remote interrupt-on-connect
1962 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1963 remote target when gdb connects to it. This is needed when you debug
1966 set remotebreak [on | off]
1968 Deprecated. Use "set/show remote interrupt-sequence" instead.
1970 tvariable $NAME [ = EXP ]
1971 Create or modify a trace state variable.
1974 List trace state variables and their values.
1976 delete tvariable $NAME ...
1977 Delete one or more trace state variables.
1980 Evaluate the given expressions without collecting anything into the
1981 trace buffer. (Valid in tracepoint actions only.)
1983 ftrace FN / FILE:LINE / *ADDR
1984 Define a fast tracepoint at the given function, line, or address.
1986 * New expression syntax
1988 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1989 GDB now parses 0b101010 identically with 42.
1993 set follow-exec-mode new|same
1994 show follow-exec-mode
1995 Control whether GDB reuses the same inferior across an exec call or
1996 creates a new one. This is useful to be able to restart the old
1997 executable after the inferior having done an exec call.
1999 set default-collect EXPR, ...
2000 show default-collect
2001 Define a list of expressions to be collected at each tracepoint.
2002 This is a useful way to ensure essential items are not overlooked,
2003 such as registers or a critical global variable.
2005 set disconnected-tracing
2006 show disconnected-tracing
2007 If set to 1, the target is instructed to continue tracing if it
2008 loses its connection to GDB. If 0, the target is to stop tracing
2011 set circular-trace-buffer
2012 show circular-trace-buffer
2013 If set to on, the target is instructed to use a circular trace buffer
2014 and discard the oldest trace frames instead of stopping the trace due
2015 to a full trace buffer. If set to off, the trace stops when the buffer
2016 fills up. Some targets may not support this.
2018 set script-extension off|soft|strict
2019 show script-extension
2020 If set to "off", the debugger does not perform any script language
2021 recognition, and all sourced files are assumed to be GDB scripts.
2022 If set to "soft" (the default), files are sourced according to
2023 filename extension, falling back to GDB scripts if the first
2025 If set to "strict", files are sourced according to filename extension.
2027 set ada trust-PAD-over-XVS on|off
2028 show ada trust-PAD-over-XVS
2029 If off, activate a workaround against a bug in the debugging information
2030 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2031 the GCC sources for more information about the GNAT encoding and
2032 PAD types in particular). It is always safe to set this option to
2033 off, but this introduces a slight performance penalty. The default
2036 * Python API Improvements
2038 ** GDB provides the new class gdb.LazyString. This is useful in
2039 some pretty-printing cases. The new method gdb.Value.lazy_string
2040 provides a simple way to create objects of this type.
2042 ** The fields returned by gdb.Type.fields now have an
2043 `is_base_class' attribute.
2045 ** The new method gdb.Type.range returns the range of an array type.
2047 ** The new method gdb.parse_and_eval can be used to parse and
2048 evaluate an expression.
2050 * New remote packets
2053 Define a trace state variable.
2056 Get the current value of a trace state variable.
2059 Set desired tracing behavior upon disconnection.
2062 Set the trace buffer to be linear or circular.
2065 Get data about the tracepoints currently in use.
2069 Process record now works correctly with hardware watchpoints.
2071 Multiple bug fixes have been made to the mips-irix port, making it
2072 much more reliable. In particular:
2073 - Debugging threaded applications is now possible again. Previously,
2074 GDB would hang while starting the program, or while waiting for
2075 the program to stop at a breakpoint.
2076 - Attaching to a running process no longer hangs.
2077 - An error occurring while loading a core file has been fixed.
2078 - Changing the value of the PC register now works again. This fixes
2079 problems observed when using the "jump" command, or when calling
2080 a function from GDB, or even when assigning a new value to $pc.
2081 - With the "finish" and "return" commands, the return value for functions
2082 returning a small array is now correctly printed.
2083 - It is now possible to break on shared library code which gets executed
2084 during a shared library init phase (code executed while executing
2085 their .init section). Previously, the breakpoint would have no effect.
2086 - GDB is now able to backtrace through the signal handler for
2087 non-threaded programs.
2089 PIE (Position Independent Executable) programs debugging is now supported.
2090 This includes debugging execution of PIC (Position Independent Code) shared
2091 libraries although for that, it should be possible to run such libraries as an
2094 *** Changes in GDB 7.0
2096 * GDB now has an interface for JIT compilation. Applications that
2097 dynamically generate code can create symbol files in memory and register
2098 them with GDB. For users, the feature should work transparently, and
2099 for JIT developers, the interface is documented in the GDB manual in the
2100 "JIT Compilation Interface" chapter.
2102 * Tracepoints may now be conditional. The syntax is as for
2103 breakpoints; either an "if" clause appended to the "trace" command,
2104 or the "condition" command is available. GDB sends the condition to
2105 the target for evaluation using the same bytecode format as is used
2106 for tracepoint actions.
2108 * The disassemble command now supports: an optional /r modifier, print the
2109 raw instructions in hex as well as in symbolic form, and an optional /m
2110 modifier to print mixed source+assembly.
2112 * Process record and replay
2114 In a architecture environment that supports ``process record and
2115 replay'', ``process record and replay'' target can record a log of
2116 the process execution, and replay it with both forward and reverse
2119 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2120 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2121 set execution-direction {forward|reverse}, for targets that support
2124 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2125 feature is available with a native GDB running on kernel version
2128 * GDB now has support for multi-byte and wide character sets on the
2129 target. Strings whose character type is wchar_t, char16_t, or
2130 char32_t are now correctly printed. GDB supports wide- and unicode-
2131 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2132 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2133 `printf'. This feature requires iconv to work properly; if your
2134 system does not have a working iconv, GDB can use GNU libiconv. See
2135 the installation instructions for more information.
2137 * GDB now supports automatic retrieval of shared library files from
2138 remote targets. To use this feature, specify a system root that begins
2139 with the `remote:' prefix, either via the `set sysroot' command or via
2140 the `--with-sysroot' configure-time option.
2142 * "info sharedlibrary" now takes an optional regex of libraries to show,
2143 and it now reports if a shared library has no debugging information.
2145 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2146 now complete on file names.
2148 * When completing in expressions, gdb will attempt to limit
2149 completions to allowable structure or union fields, where appropriate.
2150 For instance, consider:
2152 # struct example { int f1; double f2; };
2153 # struct example variable;
2156 If the user types TAB at the end of this command line, the available
2157 completions will be "f1" and "f2".
2159 * Inlined functions are now supported. They show up in backtraces, and
2160 the "step", "next", and "finish" commands handle them automatically.
2162 * GDB now supports the token-splicing (##) and stringification (#)
2163 operators when expanding macros. It also supports variable-arity
2166 * GDB now supports inspecting extra signal information, exported by
2167 the new $_siginfo convenience variable. The feature is currently
2168 implemented on linux ARM, i386 and amd64.
2170 * GDB can now display the VFP floating point registers and NEON vector
2171 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2172 can provide these registers (requires Linux 2.6.30 or later). Remote
2173 and simulator targets may also provide them.
2175 * New remote packets
2178 Search memory for a sequence of bytes.
2181 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2182 operation over reliable transport links. Use of this packet is
2183 controlled by the `set remote noack-packet' command.
2186 Kill the process with the specified process ID. Use this in preference
2187 to `k' when multiprocess protocol extensions are supported.
2190 Obtains additional operating system information
2194 Read or write additional signal information.
2196 * Removed remote protocol undocumented extension
2198 An undocumented extension to the remote protocol's `S' stop reply
2199 packet that permited the stub to pass a process id was removed.
2200 Remote servers should use the `T' stop reply packet instead.
2202 * GDB now supports multiple function calling conventions according to the
2203 DWARF-2 DW_AT_calling_convention function attribute.
2205 * The SH target utilizes the aforementioned change to distinguish between gcc
2206 and Renesas calling convention. It also adds the new CLI commands
2207 `set/show sh calling-convention'.
2209 * GDB can now read compressed debug sections, as produced by GNU gold
2210 with the --compress-debug-sections=zlib flag.
2212 * 64-bit core files are now supported on AIX.
2214 * Thread switching is now supported on Tru64.
2216 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2217 which will be allocated using malloc later in program execution.
2219 * The qXfer:libraries:read remote procotol packet now allows passing a
2220 list of section offsets.
2222 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2223 conditions handling signals delivered during attach or thread creation
2224 have also been fixed.
2226 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2227 From the user's standpoint, all unqualified instances of True and False
2228 are treated as the standard definitions, regardless of context.
2230 * GDB now parses C++ symbol and type names more flexibly. For
2233 template<typename T> class C { };
2236 GDB will now correctly handle all of:
2238 ptype C<char const *>
2239 ptype C<char const*>
2240 ptype C<const char *>
2241 ptype C<const char*>
2243 * New features in the GDB remote stub, gdbserver
2245 - The "--wrapper" command-line argument tells gdbserver to use a
2246 wrapper program to launch programs for debugging.
2248 - On PowerPC and S/390 targets, it is now possible to use a single
2249 gdbserver executable to debug both 32-bit and 64-bit programs.
2250 (This requires gdbserver itself to be built as a 64-bit executable.)
2252 - gdbserver uses the new noack protocol mode for TCP connections to
2253 reduce communications latency, if also supported and enabled in GDB.
2255 - Support for the sparc64-linux-gnu target is now included in
2258 - The amd64-linux build of gdbserver now supports debugging both
2259 32-bit and 64-bit programs.
2261 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2262 now support hardware watchpoints, and will use them automatically
2267 GDB now has support for scripting using Python. Whether this is
2268 available is determined at configure time.
2270 New GDB commands can now be written in Python.
2272 * Ada tasking support
2274 Ada tasks can now be inspected in GDB. The following commands have
2278 Print the list of Ada tasks.
2280 Print detailed information about task number N.
2282 Print the task number of the current task.
2284 Switch the context of debugging to task number N.
2286 * Support for user-defined prefixed commands. The "define" command can
2287 add new commands to existing prefixes, e.g. "target".
2289 * Multi-inferior, multi-process debugging.
2291 GDB now has generalized support for multi-inferior debugging. See
2292 "Debugging Multiple Inferiors" in the manual for more information.
2293 Although availability still depends on target support, the command
2294 set is more uniform now. The GNU/Linux specific multi-forks support
2295 has been migrated to this new framework. This implied some user
2296 visible changes; see "New commands" and also "Removed commands"
2299 * Target descriptions can now describe the target OS ABI. See the
2300 "Target Description Format" section in the user manual for more
2303 * Target descriptions can now describe "compatible" architectures
2304 to indicate that the target can execute applications for a different
2305 architecture in addition to those for the main target architecture.
2306 See the "Target Description Format" section in the user manual for
2309 * Multi-architecture debugging.
2311 GDB now includes general supports for debugging applications on
2312 hybrid systems that use more than one single processor architecture
2313 at the same time. Each such hybrid architecture still requires
2314 specific support to be added. The only hybrid architecture supported
2315 in this version of GDB is the Cell Broadband Engine.
2317 * GDB now supports integrated debugging of Cell/B.E. applications that
2318 use both the PPU and SPU architectures. To enable support for hybrid
2319 Cell/B.E. debugging, you need to configure GDB to support both the
2320 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2321 --enable-targets configure option.
2323 * Non-stop mode debugging.
2325 For some targets, GDB now supports an optional mode of operation in
2326 which you can examine stopped threads while other threads continue
2327 to execute freely. This is referred to as non-stop mode, with the
2328 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2329 section in the user manual for more information.
2331 To be able to support remote non-stop debugging, a remote stub needs
2332 to implement the non-stop mode remote protocol extensions, as
2333 described in the "Remote Non-Stop" section of the user manual. The
2334 GDB remote stub, gdbserver, has been adjusted to support these
2335 extensions on linux targets.
2337 * New commands (for set/show, see "New options" below)
2339 catch syscall [NAME(S) | NUMBER(S)]
2340 Catch system calls. Arguments, which should be names of system
2341 calls or their numbers, mean catch only those syscalls. Without
2342 arguments, every syscall will be caught. When the inferior issues
2343 any of the specified syscalls, GDB will stop and announce the system
2344 call, both when it is called and when its call returns. This
2345 feature is currently available with a native GDB running on the
2346 Linux Kernel, under the following architectures: x86, x86_64,
2347 PowerPC and PowerPC64.
2349 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2351 Search memory for a sequence of bytes.
2353 maint set python print-stack
2354 maint show python print-stack
2355 Show a stack trace when an error is encountered in a Python script.
2358 Invoke CODE by passing it to the Python interpreter.
2363 These allow macros to be defined, undefined, and listed
2367 Show operating system information about processes.
2370 List the inferiors currently under GDB's control.
2373 Switch focus to inferior number NUM.
2376 Detach from inferior number NUM.
2379 Kill inferior number NUM.
2383 set spu stop-on-load
2384 show spu stop-on-load
2385 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2387 set spu auto-flush-cache
2388 show spu auto-flush-cache
2389 Control whether to automatically flush the software-managed cache
2390 during Cell/B.E. debugging.
2392 set sh calling-convention
2393 show sh calling-convention
2394 Control the calling convention used when calling SH target functions.
2397 show debug timestamp
2398 Control display of timestamps with GDB debugging output.
2400 set disassemble-next-line
2401 show disassemble-next-line
2402 Control display of disassembled source lines or instructions when
2405 set remote noack-packet
2406 show remote noack-packet
2407 Set/show the use of remote protocol QStartNoAckMode packet. See above
2408 under "New remote packets."
2410 set remote query-attached-packet
2411 show remote query-attached-packet
2412 Control use of remote protocol `qAttached' (query-attached) packet.
2414 set remote read-siginfo-object
2415 show remote read-siginfo-object
2416 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2419 set remote write-siginfo-object
2420 show remote write-siginfo-object
2421 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2424 set remote reverse-continue
2425 show remote reverse-continue
2426 Control use of remote protocol 'bc' (reverse-continue) packet.
2428 set remote reverse-step
2429 show remote reverse-step
2430 Control use of remote protocol 'bs' (reverse-step) packet.
2432 set displaced-stepping
2433 show displaced-stepping
2434 Control displaced stepping mode. Displaced stepping is a way to
2435 single-step over breakpoints without removing them from the debuggee.
2436 Also known as "out-of-line single-stepping".
2439 show debug displaced
2440 Control display of debugging info for displaced stepping.
2442 maint set internal-error
2443 maint show internal-error
2444 Control what GDB does when an internal error is detected.
2446 maint set internal-warning
2447 maint show internal-warning
2448 Control what GDB does when an internal warning is detected.
2453 Use a wrapper program to launch programs for debugging.
2455 set multiple-symbols (all|ask|cancel)
2456 show multiple-symbols
2457 The value of this variable can be changed to adjust the debugger behavior
2458 when an expression or a breakpoint location contains an ambiguous symbol
2459 name (an overloaded function name, for instance).
2461 set breakpoint always-inserted
2462 show breakpoint always-inserted
2463 Keep breakpoints always inserted in the target, as opposed to inserting
2464 them when resuming the target, and removing them when the target stops.
2465 This option can improve debugger performance on slow remote targets.
2467 set arm fallback-mode (arm|thumb|auto)
2468 show arm fallback-mode
2469 set arm force-mode (arm|thumb|auto)
2471 These commands control how ARM GDB determines whether instructions
2472 are ARM or Thumb. The default for both settings is auto, which uses
2473 the current CPSR value for instructions without symbols; previous
2474 versions of GDB behaved as if "set arm fallback-mode arm".
2476 set disable-randomization
2477 show disable-randomization
2478 Standalone programs run with the virtual address space randomization enabled
2479 by default on some platforms. This option keeps the addresses stable across
2480 multiple debugging sessions.
2484 Control whether other threads are stopped or not when some thread hits
2489 Requests that asynchronous execution is enabled in the target, if available.
2490 In this case, it's possible to resume target in the background, and interact
2491 with GDB while the target is running. "show target-async" displays the
2492 current state of asynchronous execution of the target.
2494 set target-wide-charset
2495 show target-wide-charset
2496 The target-wide-charset is the name of the character set that GDB
2497 uses when printing characters whose type is wchar_t.
2499 set tcp auto-retry (on|off)
2501 set tcp connect-timeout
2502 show tcp connect-timeout
2503 These commands allow GDB to retry failed TCP connections to a remote stub
2504 with a specified timeout period; this is useful if the stub is launched
2505 in parallel with GDB but may not be ready to accept connections immediately.
2507 set libthread-db-search-path
2508 show libthread-db-search-path
2509 Control list of directories which GDB will search for appropriate
2512 set schedule-multiple (on|off)
2513 show schedule-multiple
2514 Allow GDB to resume all threads of all processes or only threads of
2515 the current process.
2519 Use more aggressive caching for accesses to the stack. This improves
2520 performance of remote debugging (particularly backtraces) without
2521 affecting correctness.
2523 set interactive-mode (on|off|auto)
2524 show interactive-mode
2525 Control whether GDB runs in interactive mode (on) or not (off).
2526 When in interactive mode, GDB waits for the user to answer all
2527 queries. Otherwise, GDB does not wait and assumes the default
2528 answer. When set to auto (the default), GDB determines which
2529 mode to use based on the stdin settings.
2534 For program forks, this is replaced by the new more generic `info
2535 inferiors' command. To list checkpoints, you can still use the
2536 `info checkpoints' command, which was an alias for the `info forks'
2540 Replaced by the new `inferior' command. To switch between
2541 checkpoints, you can still use the `restart' command, which was an
2542 alias for the `fork' command.
2545 This is removed, since some targets don't have a notion of
2546 processes. To switch between processes, you can still use the
2547 `inferior' command using GDB's own inferior number.
2550 For program forks, this is replaced by the new more generic `kill
2551 inferior' command. To delete a checkpoint, you can still use the
2552 `delete checkpoint' command, which was an alias for the `delete
2556 For program forks, this is replaced by the new more generic `detach
2557 inferior' command. To detach a checkpoint, you can still use the
2558 `detach checkpoint' command, which was an alias for the `detach
2561 * New native configurations
2563 x86/x86_64 Darwin i[34567]86-*-darwin*
2565 x86_64 MinGW x86_64-*-mingw*
2569 Lattice Mico32 lm32-*
2570 x86 DICOS i[34567]86-*-dicos*
2571 x86_64 DICOS x86_64-*-dicos*
2574 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2575 (mingw32ce) debugging.
2581 These commands were actually not implemented on any target.
2583 *** Changes in GDB 6.8
2585 * New native configurations
2587 NetBSD/hppa hppa*-*netbsd*
2588 Xtensa GNU/Linux xtensa*-*-linux*
2592 NetBSD/hppa hppa*-*-netbsd*
2593 Xtensa GNU/Lunux xtensa*-*-linux*
2595 * Change in command line behavior -- corefiles vs. process ids.
2597 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2598 attaching to process NUMBER fails, GDB no longer attempts to open a
2599 core file named NUMBER. Attaching to a program using the -c option
2600 is no longer supported. Instead, use the '-p' or '--pid' options.
2602 * GDB can now be built as a native debugger for debugging Windows x86
2603 (mingw32) Portable Executable (PE) programs.
2605 * Pending breakpoints no longer change their number when their address
2608 * GDB now supports breakpoints with multiple locations,
2609 including breakpoints on C++ constructors, inside C++ templates,
2610 and in inlined functions.
2612 * GDB's ability to debug optimized code has been improved. GDB more
2613 accurately identifies function bodies and lexical blocks that occupy
2614 more than one contiguous range of addresses.
2616 * Target descriptions can now describe registers for PowerPC.
2618 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2619 registers on PowerPC targets.
2621 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2622 targets even when the libthread_db library is not available.
2624 * The GDB remote stub, gdbserver, now supports the new file transfer
2625 commands (remote put, remote get, and remote delete).
2627 * The GDB remote stub, gdbserver, now supports run and attach in
2628 extended-remote mode.
2630 * hppa*64*-*-hpux11* target broken
2631 The debugger is unable to start a program and fails with the following
2632 error: "Error trying to get information about dynamic linker".
2633 The gdb-6.7 release is also affected.
2635 * GDB now supports the --enable-targets= configure option to allow
2636 building a single GDB executable that supports multiple remote
2637 target architectures.
2639 * GDB now supports debugging C and C++ programs which use the
2640 Decimal Floating Point extension. In addition, the PowerPC target
2641 now has a set of pseudo-registers to inspect decimal float values
2642 stored in two consecutive float registers.
2644 * The -break-insert MI command can optionally create pending
2647 * Improved support for debugging Ada
2648 Many improvements to the Ada language support have been made. These
2650 - Better support for Ada2005 interface types
2651 - Improved handling of arrays and slices in general
2652 - Better support for Taft-amendment types
2653 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2655 - Improved command completion in Ada
2658 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2663 set print frame-arguments (all|scalars|none)
2664 show print frame-arguments
2665 The value of this variable can be changed to control which argument
2666 values should be printed by the debugger when displaying a frame.
2671 Transfer files to and from a remote target, and delete remote files.
2678 Transfer files to and from a remote target, and delete remote files.
2680 * New remote packets
2687 Open, close, read, write, and delete files on the remote system.
2690 Attach to an existing process on the remote system, in extended-remote
2694 Run a new process on the remote system, in extended-remote mode.
2696 *** Changes in GDB 6.7
2698 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2699 bfd, libiberty and opcodes, as revealed by static analysis donated by
2700 Coverity, Inc. (http://scan.coverity.com).
2702 * When looking up multiply-defined global symbols, GDB will now prefer the
2703 symbol definition in the current shared library if it was built using the
2704 -Bsymbolic linker option.
2706 * When the Text User Interface (TUI) is not configured, GDB will now
2707 recognize the -tui command-line option and print a message that the TUI
2710 * The GDB remote stub, gdbserver, now has lower overhead for high
2711 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2713 * GDB for MIPS targets now autodetects whether a remote target provides
2714 32-bit or 64-bit register values.
2716 * Support for C++ member pointers has been improved.
2718 * GDB now understands XML target descriptions, which specify the
2719 target's overall architecture. GDB can read a description from
2720 a local file or over the remote serial protocol.
2722 * Vectors of single-byte data use a new integer type which is not
2723 automatically displayed as character or string data.
2725 * The /s format now works with the print command. It displays
2726 arrays of single-byte integers and pointers to single-byte integers
2729 * Target descriptions can now describe target-specific registers,
2730 for architectures which have implemented the support (currently
2731 only ARM, M68K, and MIPS).
2733 * GDB and the GDB remote stub, gdbserver, now support the XScale
2736 * The GDB remote stub, gdbserver, has been updated to support
2737 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2738 has been rewritten to use the standard GDB remote protocol.
2740 * GDB can now step into C++ functions which are called through thunks.
2742 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2744 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2745 layout. It also supports a TextSeg= and DataSeg= response when only
2746 segment base addresses (rather than offsets) are available.
2748 * The /i format now outputs any trailing branch delay slot instructions
2749 immediately following the last instruction within the count specified.
2751 * The GDB remote protocol "T" stop reply packet now supports a
2752 "library" response. Combined with the new "qXfer:libraries:read"
2753 packet, this response allows GDB to debug shared libraries on targets
2754 where the operating system manages the list of loaded libraries (e.g.
2755 Windows and SymbianOS).
2757 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2758 (DLLs) on Windows and Windows CE targets.
2760 * GDB now supports a faster verification that a .debug file matches its binary
2761 according to its build-id signature, if the signature is present.
2767 Enable or disable hardware flow control (RTS/CTS) on the serial port
2768 when debugging using remote targets.
2770 set mem inaccessible-by-default
2771 show mem inaccessible-by-default
2772 If the target supplies a memory map, for instance via the remote
2773 protocol's "qXfer:memory-map:read" packet, setting this variable
2774 prevents GDB from accessing memory outside the memory map. This
2775 is useful for targets with memory mapped registers or which react
2776 badly to accesses of unmapped address space.
2778 set breakpoint auto-hw
2779 show breakpoint auto-hw
2780 If the target supplies a memory map, for instance via the remote
2781 protocol's "qXfer:memory-map:read" packet, setting this variable
2782 lets GDB use hardware breakpoints automatically for memory regions
2783 where it can not use software breakpoints. This covers both the
2784 "break" command and internal breakpoints used for other commands
2785 including "next" and "finish".
2788 catch exception unhandled
2789 Stop the program execution when Ada exceptions are raised.
2792 Stop the program execution when an Ada assertion failed.
2796 Set an alternate system root for target files. This is a more
2797 general version of "set solib-absolute-prefix", which is now
2798 an alias to "set sysroot".
2801 Provide extended SPU facility status information. This set of
2802 commands is available only when debugging the Cell/B.E. SPU
2805 * New native configurations
2807 OpenBSD/sh sh*-*openbsd*
2810 unset tdesc filename
2812 Use the specified local file as an XML target description, and do
2813 not query the target for its built-in description.
2817 OpenBSD/sh sh*-*-openbsd*
2818 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2819 Toshiba Media Processor mep-elf
2821 * New remote packets
2824 Ignore the specified signals; pass them directly to the debugged program
2825 without stopping other threads or reporting them to GDB.
2827 qXfer:features:read:
2828 Read an XML target description from the target, which describes its
2833 Read or write contents of an spufs file on the target system. These
2834 packets are available only on the Cell/B.E. SPU architecture.
2836 qXfer:libraries:read:
2837 Report the loaded shared libraries. Combined with new "T" packet
2838 response, this packet allows GDB to debug shared libraries on
2839 targets where the operating system manages the list of loaded
2840 libraries (e.g. Windows and SymbianOS).
2844 Support for these obsolete configurations has been removed.
2852 i[34567]86-*-lynxos*
2853 i[34567]86-*-netware*
2854 i[34567]86-*-sco3.2v5*
2855 i[34567]86-*-sco3.2v4*
2857 i[34567]86-*-sysv4.2*
2860 i[34567]86-*-unixware2*
2861 i[34567]86-*-unixware*
2870 * Other removed features
2877 Various m68k-only ROM monitors.
2884 Various Renesas ROM monitors and debugging interfaces for SH and
2889 Support for a Macraigor serial interface to on-chip debugging.
2890 GDB does not directly support the newer parallel or USB
2895 A debug information format. The predecessor to DWARF 2 and
2896 DWARF 3, which are still supported.
2898 Support for the HP aCC compiler on HP-UX/PA-RISC
2900 SOM-encapsulated symbolic debugging information, automatic
2901 invocation of pxdb, and the aCC custom C++ ABI. This does not
2902 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2903 with aCC can still be debugged on an assembly level.
2905 MIPS ".pdr" sections
2907 A MIPS-specific format used to describe stack frame layout
2908 in debugging information.
2912 GDB could work with an older version of Guile to debug
2913 the interpreter and Scheme programs running in it.
2915 set mips stack-arg-size
2916 set mips saved-gpreg-size
2918 Use "set mips abi" to control parameter passing for MIPS.
2920 *** Changes in GDB 6.6
2925 Cell Broadband Engine SPU spu-elf
2927 * GDB can now be configured as a cross-debugger targeting native Windows
2928 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2929 running on a Windows system over TCP/IP to debug Windows programs.
2931 * The GDB remote stub, gdbserver, has been updated to support Windows and
2932 Cygwin debugging. Both single-threaded and multi-threaded programs are
2935 * The "set trust-readonly-sections" command works again. This command was
2936 broken in GDB 6.3, 6.4, and 6.5.
2938 * The "load" command now supports writing to flash memory, if the remote
2939 stub provides the required support.
2941 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2942 longer requires symbolic debug information (e.g. DWARF-2).
2947 unset substitute-path
2948 show substitute-path
2949 Manage a list of substitution rules that GDB uses to rewrite the name
2950 of the directories where the sources are located. This can be useful
2951 for instance when the sources were moved to a different location
2952 between compilation and debugging.
2956 Print each CLI command as it is executed. Each command is prefixed with
2957 a number of `+' symbols representing the nesting depth.
2958 The source command now has a `-v' option to enable the same feature.
2962 The ARM Demon monitor support (RDP protocol, "target rdp").
2964 Kernel Object Display, an embedded debugging feature which only worked with
2965 an obsolete version of Cisco IOS.
2967 The 'set download-write-size' and 'show download-write-size' commands.
2969 * New remote packets
2972 Tell a stub about GDB client features, and request remote target features.
2973 The first feature implemented is PacketSize, which allows the target to
2974 specify the size of packets it can handle - to minimize the number of
2975 packets required and improve performance when connected to a remote
2979 Fetch an OS auxilliary vector from the remote stub. This packet is a
2980 more efficient replacement for qPart:auxv:read.
2982 qXfer:memory-map:read:
2983 Fetch a memory map from the remote stub, including information about
2984 RAM, ROM, and flash memory devices.
2989 Erase and program a flash memory device.
2991 * Removed remote packets
2994 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2995 used it, and only gdbserver implemented it.
2997 *** Changes in GDB 6.5
3001 Renesas M32C/M16C m32c-elf
3003 Morpho Technologies ms1 ms1-elf
3007 init-if-undefined Initialize a convenience variable, but
3008 only if it doesn't already have a value.
3010 The following commands are presently only implemented for native GNU/Linux:
3012 checkpoint Save a snapshot of the program state.
3014 restart <n> Return the program state to a
3015 previously saved state.
3017 info checkpoints List currently saved checkpoints.
3019 delete-checkpoint <n> Delete a previously saved checkpoint.
3021 set|show detach-on-fork Tell gdb whether to detach from a newly
3022 forked process, or to keep debugging it.
3024 info forks List forks of the user program that
3025 are available to be debugged.
3027 fork <n> Switch to debugging one of several
3028 forks of the user program that are
3029 available to be debugged.
3031 delete-fork <n> Delete a fork from the list of forks
3032 that are available to be debugged (and
3033 kill the forked process).
3035 detach-fork <n> Delete a fork from the list of forks
3036 that are available to be debugged (and
3037 allow the process to continue).
3041 Morpho Technologies ms2 ms1-elf
3043 * Improved Windows host support
3045 GDB now builds as a cross debugger hosted on i686-mingw32, including
3046 native console support, and remote communications using either
3047 network sockets or serial ports.
3049 * Improved Modula-2 language support
3051 GDB can now print most types in the Modula-2 syntax. This includes:
3052 basic types, set types, record types, enumerated types, range types,
3053 pointer types and ARRAY types. Procedure var parameters are correctly
3054 printed and hexadecimal addresses and character constants are also
3055 written in the Modula-2 syntax. Best results can be obtained by using
3056 GNU Modula-2 together with the -gdwarf-2 command line option.
3060 The ARM rdi-share module.
3062 The Netware NLM debug server.
3064 *** Changes in GDB 6.4
3066 * New native configurations
3068 OpenBSD/arm arm*-*-openbsd*
3069 OpenBSD/mips64 mips64-*-openbsd*
3073 Morpho Technologies ms1 ms1-elf
3075 * New command line options
3077 --batch-silent As for --batch, but totally silent.
3078 --return-child-result The debugger will exist with the same value
3079 the child (debugged) program exited with.
3080 --eval-command COMMAND, -ex COMMAND
3081 Execute a single GDB CLI command. This may be
3082 specified multiple times and in conjunction
3083 with the --command (-x) option.
3085 * Deprecated commands removed
3087 The following commands, that were deprecated in 2000, have been
3091 set|show arm disassembly-flavor set|show arm disassembler
3092 othernames set arm disassembler
3093 set|show remotedebug set|show debug remote
3094 set|show archdebug set|show debug arch
3095 set|show eventdebug set|show debug event
3098 * New BSD user-level threads support
3100 It is now possible to debug programs using the user-level threads
3101 library on OpenBSD and FreeBSD. Currently supported (target)
3104 FreeBSD/amd64 x86_64-*-freebsd*
3105 FreeBSD/i386 i386-*-freebsd*
3106 OpenBSD/i386 i386-*-openbsd*
3108 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3109 are not yet supported.
3111 * New support for Matsushita MN10300 w/sim added
3112 (Work in progress). mn10300-elf.
3114 * REMOVED configurations and files
3116 VxWorks and the XDR protocol *-*-vxworks
3117 Motorola MCORE mcore-*-*
3118 National Semiconductor NS32000 ns32k-*-*
3120 * New "set print array-indexes" command
3122 After turning this setting "on", GDB prints the index of each element
3123 when displaying arrays. The default is "off" to preserve the previous
3126 * VAX floating point support
3128 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3130 * User-defined command support
3132 In addition to using $arg0..$arg9 for argument passing, it is now possible
3133 to use $argc to determine now many arguments have been passed. See the
3134 section on user-defined commands in the user manual for more information.
3136 *** Changes in GDB 6.3:
3138 * New command line option
3140 GDB now accepts -l followed by a number to set the timeout for remote
3143 * GDB works with GCC -feliminate-dwarf2-dups
3145 GDB now supports a more compact representation of DWARF-2 debug
3146 information using DW_FORM_ref_addr references. These are produced
3147 by GCC with the option -feliminate-dwarf2-dups and also by some
3148 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3149 to use -feliminate-dwarf2-dups.
3151 * Internationalization
3153 When supported by the host system, GDB will be built with
3154 internationalization (libintl). The task of marking up the sources is
3155 continued, we're looking forward to our first translation.
3159 Initial support for debugging programs compiled with the GNAT
3160 implementation of the Ada programming language has been integrated
3161 into GDB. In this release, support is limited to expression evaluation.
3163 * New native configurations
3165 GNU/Linux/m32r m32r-*-linux-gnu
3169 GDB's remote protocol now includes support for the 'p' packet. This
3170 packet is used to fetch individual registers from a remote inferior.
3172 * END-OF-LIFE registers[] compatibility module
3174 GDB's internal register infrastructure has been completely rewritten.
3175 The new infrastructure making possible the implementation of key new
3176 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3179 GDB 6.3 will be the last release to include the the registers[]
3180 compatibility module that allowed out-of-date configurations to
3181 continue to work. This change directly impacts the following
3191 powerpc bdm protocol
3193 Unless there is activity to revive these configurations, they will be
3194 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3196 * OBSOLETE configurations and files
3198 Configurations that have been declared obsolete in this release have
3199 been commented out. Unless there is activity to revive these
3200 configurations, the next release of GDB will have their sources
3201 permanently REMOVED.
3210 *** Changes in GDB 6.2.1:
3212 * MIPS `break main; run' gave an heuristic-fence-post warning
3214 When attempting to run even a simple program, a warning about
3215 heuristic-fence-post being hit would be reported. This problem has
3218 * MIPS IRIX 'long double' crashed GDB
3220 When examining a long double variable, GDB would get a segmentation
3221 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3222 IRIX long double values).
3226 A bug in the VAX stack code was causing problems with the "next"
3227 command. This problem has been fixed.
3229 *** Changes in GDB 6.2:
3231 * Fix for ``many threads''
3233 On GNU/Linux systems that use the NPTL threads library, a program
3234 rapidly creating and deleting threads would confuse GDB leading to the
3237 ptrace: No such process.
3238 thread_db_get_info: cannot get thread info: generic error
3240 This problem has been fixed.
3242 * "-async" and "-noasync" options removed.
3244 Support for the broken "-noasync" option has been removed (it caused
3247 * New ``start'' command.
3249 This command runs the program until the begining of the main procedure.
3251 * New BSD Kernel Data Access Library (libkvm) interface
3253 Using ``target kvm'' it is now possible to debug kernel core dumps and
3254 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3255 platforms. Currently supported (native-only) configurations are:
3257 FreeBSD/amd64 x86_64-*-freebsd*
3258 FreeBSD/i386 i?86-*-freebsd*
3259 NetBSD/i386 i?86-*-netbsd*
3260 NetBSD/m68k m68*-*-netbsd*
3261 NetBSD/sparc sparc-*-netbsd*
3262 OpenBSD/amd64 x86_64-*-openbsd*
3263 OpenBSD/i386 i?86-*-openbsd*
3264 OpenBSD/m68k m68*-openbsd*
3265 OpenBSD/sparc sparc-*-openbsd*
3267 * Signal trampoline code overhauled
3269 Many generic problems with GDB's signal handling code have been fixed.
3270 These include: backtraces through non-contiguous stacks; recognition
3271 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3272 call; backtrace through a signal trampoline; step into and out of
3273 signal handlers; and single-stepping in the signal trampoline.
3275 Please note that kernel bugs are a limiting factor here. These
3276 features have been shown to work on an s390 GNU/Linux system that
3277 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3279 * Cygwin support for DWARF 2 added.
3281 * New native configurations
3283 GNU/Linux/hppa hppa*-*-linux*
3284 OpenBSD/hppa hppa*-*-openbsd*
3285 OpenBSD/m68k m68*-*-openbsd*
3286 OpenBSD/m88k m88*-*-openbsd*
3287 OpenBSD/powerpc powerpc-*-openbsd*
3288 NetBSD/vax vax-*-netbsd*
3289 OpenBSD/vax vax-*-openbsd*
3291 * END-OF-LIFE frame compatibility module
3293 GDB's internal frame infrastructure has been completely rewritten.
3294 The new infrastructure making it possible to support key new features
3295 including DWARF 2 Call Frame Information. To aid in the task of
3296 migrating old configurations to this new infrastructure, a
3297 compatibility module, that allowed old configurations to continue to
3298 work, was also included.
3300 GDB 6.2 will be the last release to include this frame compatibility
3301 module. This change directly impacts the following configurations:
3311 Unless there is activity to revive these configurations, they will be
3312 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3314 * REMOVED configurations and files
3316 Sun 3, running SunOS 3 m68*-*-sunos3*
3317 Sun 3, running SunOS 4 m68*-*-sunos4*
3318 Sun 2, running SunOS 3 m68000-*-sunos3*
3319 Sun 2, running SunOS 4 m68000-*-sunos4*
3320 Motorola 680x0 running LynxOS m68*-*-lynxos*
3321 AT&T 3b1/Unix pc m68*-att-*
3322 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3323 decstation mips-dec-* mips-little-*
3324 riscos mips-*-riscos* mips-*-sysv*
3325 sonymips mips-sony-*
3326 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3328 *** Changes in GDB 6.1.1:
3330 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3332 The TUI (Text-mode User Interface) is now built as part of a default
3333 GDB configuration. It is enabled by either selecting the TUI with the
3334 command line option "-i=tui" or by running the separate "gdbtui"
3335 program. For more information on the TUI, see the manual "Debugging
3338 * Pending breakpoint support (also included in GDB 6.1)
3340 Support has been added to allow you to specify breakpoints in shared
3341 libraries that have not yet been loaded. If a breakpoint location
3342 cannot be found, and the "breakpoint pending" option is set to auto,
3343 GDB queries you if you wish to make the breakpoint pending on a future
3344 shared-library load. If and when GDB resolves the breakpoint symbol,
3345 the pending breakpoint is removed as one or more regular breakpoints
3348 Pending breakpoints are very useful for GCJ Java debugging.
3350 * Fixed ISO-C build problems
3352 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3353 non ISO-C code that stopped them being built using a more strict ISO-C
3354 compiler (e.g., IBM's C compiler).
3356 * Fixed build problem on IRIX 5
3358 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3359 wasn't able to compile compile on an IRIX 5 system.
3361 * Added execute permission to gdb/gdbserver/configure
3363 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3364 permission. This bug would cause configure to fail on a number of
3365 systems (Solaris, IRIX). Ref: server/519.
3367 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3369 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3370 has been updated to use constant array sizes.
3372 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3374 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3375 its generated DWARF Call Frame Info. This encoding was causing GDB to
3376 panic, that panic has been fixed. Ref: gdb/1628.
3378 * Fixed a problem when examining parameters in shared library code.
3380 When examining parameters in optimized shared library code generated
3381 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3382 not available''. GDB now correctly displays the variable's value.
3384 *** Changes in GDB 6.1:
3386 * Removed --with-mmalloc
3388 Support for the mmalloc memory manager has been removed, as it
3389 conflicted with the internal gdb byte cache.
3391 * Changes in AMD64 configurations
3393 The AMD64 target now includes the %cs and %ss registers. As a result
3394 the AMD64 remote protocol has changed; this affects the floating-point
3395 and SSE registers. If you rely on those registers for your debugging,
3396 you should upgrade gdbserver on the remote side.
3398 * Revised SPARC target
3400 The SPARC target has been completely revised, incorporating the
3401 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3402 support for LynxOS and SunOS 4 has been dropped. Calling functions
3403 from within GDB on operating systems with a non-executable stack
3404 (Solaris, OpenBSD) now works.
3408 GDB has a new C++ demangler which does a better job on the mangled
3409 names generated by current versions of g++. It also runs faster, so
3410 with this and other changes gdb should now start faster on large C++
3413 * DWARF 2 Location Expressions
3415 GDB support for location expressions has been extended to support function
3416 arguments and frame bases. Older versions of GDB could crash when they
3419 * C++ nested types and namespaces
3421 GDB's support for nested types and namespaces in C++ has been
3422 improved, especially if you use the DWARF 2 debugging format. (This
3423 is the default for recent versions of GCC on most platforms.)
3424 Specifically, if you have a class "Inner" defined within a class or
3425 namespace "Outer", then GDB realizes that the class's name is
3426 "Outer::Inner", not simply "Inner". This should greatly reduce the
3427 frequency of complaints about not finding RTTI symbols. In addition,
3428 if you are stopped at inside of a function defined within a namespace,
3429 GDB modifies its name lookup accordingly.
3431 * New native configurations
3433 NetBSD/amd64 x86_64-*-netbsd*
3434 OpenBSD/amd64 x86_64-*-openbsd*
3435 OpenBSD/alpha alpha*-*-openbsd*
3436 OpenBSD/sparc sparc-*-openbsd*
3437 OpenBSD/sparc64 sparc64-*-openbsd*
3439 * New debugging protocols
3441 M32R with SDI protocol m32r-*-elf*
3443 * "set prompt-escape-char" command deleted.
3445 The command "set prompt-escape-char" has been deleted. This command,
3446 and its very obscure effet on GDB's prompt, was never documented,
3447 tested, nor mentioned in the NEWS file.
3449 * OBSOLETE configurations and files
3451 Configurations that have been declared obsolete in this release have
3452 been commented out. Unless there is activity to revive these
3453 configurations, the next release of GDB will have their sources
3454 permanently REMOVED.
3456 Sun 3, running SunOS 3 m68*-*-sunos3*
3457 Sun 3, running SunOS 4 m68*-*-sunos4*
3458 Sun 2, running SunOS 3 m68000-*-sunos3*
3459 Sun 2, running SunOS 4 m68000-*-sunos4*
3460 Motorola 680x0 running LynxOS m68*-*-lynxos*
3461 AT&T 3b1/Unix pc m68*-att-*
3462 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3463 decstation mips-dec-* mips-little-*
3464 riscos mips-*-riscos* mips-*-sysv*
3465 sonymips mips-sony-*
3466 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3468 * REMOVED configurations and files
3470 SGI Irix-4.x mips-sgi-irix4 or iris4
3471 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3472 Z8000 simulator z8k-zilog-none or z8ksim
3473 Matsushita MN10200 w/simulator mn10200-*-*
3474 H8/500 simulator h8500-hitachi-hms or h8500hms
3475 HP/PA running BSD hppa*-*-bsd*
3476 HP/PA running OSF/1 hppa*-*-osf*
3477 HP/PA Pro target hppa*-*-pro*
3478 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3479 386BSD i[3456]86-*-bsd*
3480 Sequent family i[3456]86-sequent-sysv4*
3481 i[3456]86-sequent-sysv*
3482 i[3456]86-sequent-bsd*
3483 SPARC running LynxOS sparc-*-lynxos*
3484 SPARC running SunOS 4 sparc-*-sunos4*
3485 Tsqware Sparclet sparclet-*-*
3486 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3488 *** Changes in GDB 6.0:
3492 Support for debugging the Objective-C programming language has been
3493 integrated into GDB.
3495 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3497 DWARF 2's Call Frame Information makes available compiler generated
3498 information that more exactly describes the program's run-time stack.
3499 By using this information, GDB is able to provide more robust stack
3502 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3503 have been updated to use a new backtrace mechanism which includes
3504 DWARF 2 CFI support.
3508 GDB's remote protocol has been extended to include support for hosted
3509 file I/O (where the remote target uses GDB's file system). See GDB's
3510 remote protocol documentation for details.
3512 * All targets using the new architecture framework.
3514 All of GDB's targets have been updated to use the new internal
3515 architecture framework. The way is now open for future GDB releases
3516 to include cross-architecture native debugging support (i386 on amd64,
3519 * GNU/Linux's Thread Local Storage (TLS)
3521 GDB now includes support for for the GNU/Linux implementation of
3522 per-thread variables.
3524 * GNU/Linux's Native POSIX Thread Library (NPTL)
3526 GDB's thread code has been updated to work with either the new
3527 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3529 * Separate debug info.
3531 GDB, in conjunction with BINUTILS, now supports a mechanism for
3532 automatically loading debug information from a separate file. Instead
3533 of shipping full debug and non-debug versions of system libraries,
3534 system integrators can now instead ship just the stripped libraries
3535 and optional debug files.
3537 * DWARF 2 Location Expressions
3539 DWARF 2 Location Expressions allow the compiler to more completely
3540 describe the location of variables (even in optimized code) to the
3543 GDB now includes preliminary support for location expressions (support
3544 for DW_OP_piece is still missing).
3548 A number of long standing bugs that caused GDB to die while starting a
3549 Java application have been fixed. GDB's Java support is now
3550 considered "useable".
3552 * GNU/Linux support for fork, vfork, and exec.
3554 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3555 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3558 * GDB supports logging output to a file
3560 There are two new commands, "set logging" and "show logging", which can be
3561 used to capture GDB's output to a file.
3563 * The meaning of "detach" has changed for gdbserver
3565 The "detach" command will now resume the application, as documented. To
3566 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3569 * d10v, m68hc11 `regs' command deprecated
3571 The `info registers' command has been updated so that it displays the
3572 registers using a format identical to the old `regs' command.
3576 A new command, "maint set profile on/off", has been added. This command can
3577 be used to enable or disable profiling while running GDB, to profile a
3578 session or a set of commands. In addition there is a new configure switch,
3579 "--enable-profiling", which will cause GDB to be compiled with profiling
3580 data, for more informative profiling results.
3582 * Default MI syntax changed to "mi2".
3584 The default MI (machine interface) syntax, enabled by the command line
3585 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3586 "mi1", can be enabled by specifying the option "-i=mi1".
3588 Support for the original "mi0" syntax (included in GDB 5.0) has been
3591 Fix for gdb/192: removed extraneous space when displaying frame level.
3592 Fix for gdb/672: update changelist is now output in mi list format.
3593 Fix for gdb/702: a -var-assign that updates the value now shows up
3594 in a subsequent -var-update.
3596 * New native configurations.
3598 FreeBSD/amd64 x86_64-*-freebsd*
3600 * Multi-arched targets.
3602 HP/PA HPUX11 hppa*-*-hpux*
3603 Renesas M32R/D w/simulator m32r-*-elf*
3605 * OBSOLETE configurations and files
3607 Configurations that have been declared obsolete in this release have
3608 been commented out. Unless there is activity to revive these
3609 configurations, the next release of GDB will have their sources
3610 permanently REMOVED.
3612 Z8000 simulator z8k-zilog-none or z8ksim
3613 Matsushita MN10200 w/simulator mn10200-*-*
3614 H8/500 simulator h8500-hitachi-hms or h8500hms
3615 HP/PA running BSD hppa*-*-bsd*
3616 HP/PA running OSF/1 hppa*-*-osf*
3617 HP/PA Pro target hppa*-*-pro*
3618 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3619 Sequent family i[3456]86-sequent-sysv4*
3620 i[3456]86-sequent-sysv*
3621 i[3456]86-sequent-bsd*
3622 Tsqware Sparclet sparclet-*-*
3623 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3625 * REMOVED configurations and files
3628 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3629 IBM AIX PS/2 i[3456]86-*-aix
3630 i386 running Mach 3.0 i[3456]86-*-mach3*
3631 i386 running Mach i[3456]86-*-mach*
3632 i386 running OSF/1 i[3456]86-*osf1mk*
3633 HP/Apollo 68k Family m68*-apollo*-sysv*,
3635 m68*-hp-bsd*, m68*-hp-hpux*
3636 Argonaut Risc Chip (ARC) arc-*-*
3637 Mitsubishi D30V d30v-*-*
3638 Fujitsu FR30 fr30-*-elf*
3639 OS/9000 i[34]86-*-os9k
3640 I960 with MON960 i960-*-coff
3642 * MIPS $fp behavior changed
3644 The convenience variable $fp, for the MIPS, now consistently returns
3645 the address of the current frame's base. Previously, depending on the
3646 context, $fp could refer to either $sp or the current frame's base
3647 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3648 The GNU Source-Level Debugger''.
3650 *** Changes in GDB 5.3:
3652 * GNU/Linux shared library multi-threaded performance improved.
3654 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3655 `/proc', in preference to `ptrace' for memory reads. This may result
3656 in an improvement in the start-up time of multi-threaded, shared
3657 library applications when run under GDB. One GDB user writes: ``loads
3658 shared libs like mad''.
3660 * ``gdbserver'' now supports multi-threaded applications on some targets
3662 Support for debugging multi-threaded applications which use
3663 the GNU/Linux LinuxThreads package has been added for
3664 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3665 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3667 * GDB now supports C/C++ preprocessor macros.
3669 GDB now expands preprocessor macro invocations in C/C++ expressions,
3670 and provides various commands for showing macro definitions and how
3673 The new command `macro expand EXPRESSION' expands any macro
3674 invocations in expression, and shows the result.
3676 The new command `show macro MACRO-NAME' shows the definition of the
3677 macro named MACRO-NAME, and where it was defined.
3679 Most compilers don't include information about macros in the debugging
3680 information by default. In GCC 3.1, for example, you need to compile
3681 your program with the options `-gdwarf-2 -g3'. If the macro
3682 information is present in the executable, GDB will read it.
3684 * Multi-arched targets.
3686 DEC Alpha (partial) alpha*-*-*
3687 DEC VAX (partial) vax-*-*
3689 National Semiconductor NS32000 (partial) ns32k-*-*
3690 Motorola 68000 (partial) m68k-*-*
3691 Motorola MCORE mcore-*-*
3695 Fujitsu FRV architecture added by Red Hat frv*-*-*
3698 * New native configurations
3700 Alpha NetBSD alpha*-*-netbsd*
3701 SH NetBSD sh*-*-netbsdelf*
3702 MIPS NetBSD mips*-*-netbsd*
3703 UltraSPARC NetBSD sparc64-*-netbsd*
3705 * OBSOLETE configurations and files
3707 Configurations that have been declared obsolete in this release have
3708 been commented out. Unless there is activity to revive these
3709 configurations, the next release of GDB will have their sources
3710 permanently REMOVED.
3712 Mitsubishi D30V d30v-*-*
3713 OS/9000 i[34]86-*-os9k
3714 IBM AIX PS/2 i[3456]86-*-aix
3715 Fujitsu FR30 fr30-*-elf*
3716 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3717 Argonaut Risc Chip (ARC) arc-*-*
3718 i386 running Mach 3.0 i[3456]86-*-mach3*
3719 i386 running Mach i[3456]86-*-mach*
3720 i386 running OSF/1 i[3456]86-*osf1mk*
3721 HP/Apollo 68k Family m68*-apollo*-sysv*,
3723 m68*-hp-bsd*, m68*-hp-hpux*
3724 I960 with MON960 i960-*-coff
3726 * OBSOLETE languages
3728 CHILL, a Pascal like language used by telecommunications companies.
3730 * REMOVED configurations and files
3732 AMD 29k family via UDI a29k-amd-udi, udi29k
3733 A29K VxWorks a29k-*-vxworks
3734 AMD 29000 embedded, using EBMON a29k-none-none
3735 AMD 29000 embedded with COFF a29k-none-coff
3736 AMD 29000 embedded with a.out a29k-none-aout
3738 testsuite/gdb.hp/gdb.threads-hp/ directory
3740 * New command "set max-user-call-depth <nnn>"
3742 This command allows the user to limit the call depth of user-defined
3743 commands. The default is 1024.
3745 * Changes in FreeBSD/i386 native debugging.
3747 Support for the "generate-core-file" has been added.
3749 * New commands "dump", "append", and "restore".
3751 These commands allow data to be copied from target memory
3752 to a bfd-format or binary file (dump and append), and back
3753 from a file into memory (restore).
3755 * Improved "next/step" support on multi-processor Alpha Tru64.
3757 The previous single-step mechanism could cause unpredictable problems,
3758 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3759 of a software single-step mechanism prevents this.
3761 *** Changes in GDB 5.2.1:
3769 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3770 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3771 Fix, by Joel Brobecker imported from mainline.
3773 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3774 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3775 Fix, by Fred Fish, imported from mainline.
3777 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3778 Surprisingly enough, it works now.
3779 By Michal Ludvig, imported from mainline.
3781 i386 hardware watchpoint support:
3782 avoid misses on second run for some targets.
3783 By Pierre Muller, imported from mainline.
3785 *** Changes in GDB 5.2:
3787 * New command "set trust-readonly-sections on[off]".
3789 This command is a hint that tells gdb that read-only sections
3790 really are read-only (ie. that their contents will not change).
3791 In this mode, gdb will go to the object file rather than the
3792 target to read memory from read-only sections (such as ".text").
3793 This can be a significant performance improvement on some
3794 (notably embedded) targets.
3796 * New command "generate-core-file" (or "gcore").
3798 This new gdb command allows the user to drop a core file of the child
3799 process state at any time. So far it's been implemented only for
3800 GNU/Linux and Solaris, but should be relatively easily ported to other
3801 hosts. Argument is core file name (defaults to core.<pid>).
3803 * New command line option
3805 GDB now accepts --pid or -p followed by a process id.
3807 * Change in command line behavior -- corefiles vs. process ids.
3809 There is a subtle behavior in the way in which GDB handles
3810 command line arguments. The first non-flag argument is always
3811 a program to debug, but the second non-flag argument may either
3812 be a corefile or a process id. Previously, GDB would attempt to
3813 open the second argument as a corefile, and if that failed, would
3814 issue a superfluous error message and then attempt to attach it as
3815 a process. Now, if the second argument begins with a non-digit,
3816 it will be treated as a corefile. If it begins with a digit,
3817 GDB will attempt to attach it as a process, and if no such process
3818 is found, will then attempt to open it as a corefile.
3820 * Changes in ARM configurations.
3822 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3823 configuration is fully multi-arch.
3825 * New native configurations
3827 ARM NetBSD arm*-*-netbsd*
3828 x86 OpenBSD i[3456]86-*-openbsd*
3829 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3830 Sparc64 running FreeBSD sparc64-*-freebsd*
3834 Sanyo XStormy16 xstormy16-elf
3836 * OBSOLETE configurations and files
3838 Configurations that have been declared obsolete in this release have
3839 been commented out. Unless there is activity to revive these
3840 configurations, the next release of GDB will have their sources
3841 permanently REMOVED.
3843 AMD 29k family via UDI a29k-amd-udi, udi29k
3844 A29K VxWorks a29k-*-vxworks
3845 AMD 29000 embedded, using EBMON a29k-none-none
3846 AMD 29000 embedded with COFF a29k-none-coff
3847 AMD 29000 embedded with a.out a29k-none-aout
3849 testsuite/gdb.hp/gdb.threads-hp/ directory
3851 * REMOVED configurations and files
3853 TI TMS320C80 tic80-*-*
3855 PowerPC Solaris powerpcle-*-solaris*
3856 PowerPC Windows NT powerpcle-*-cygwin32
3857 PowerPC Netware powerpc-*-netware*
3858 Harris/CXUX m88k m88*-harris-cxux*
3859 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3860 ns32k-utek-sysv* ns32k-utek-*
3861 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3862 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3863 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3864 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3865 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3867 * Changes to command line processing
3869 The new `--args' feature can be used to specify command-line arguments
3870 for the inferior from gdb's command line.
3872 * Changes to key bindings
3874 There is a new `operate-and-get-next' function bound to `C-o'.
3876 *** Changes in GDB 5.1.1
3878 Fix compile problem on DJGPP.
3880 Fix a problem with floating-point registers on the i386 being
3883 Fix to stop GDB crashing on .debug_str debug info.
3885 Numerous documentation fixes.
3887 Numerous testsuite fixes.
3889 *** Changes in GDB 5.1:
3891 * New native configurations
3893 Alpha FreeBSD alpha*-*-freebsd*
3894 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3895 MIPS GNU/Linux mips*-*-linux*
3896 MIPS SGI Irix 6.x mips*-sgi-irix6*
3897 ia64 AIX ia64-*-aix*
3898 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3902 Motorola 68HC11 and 68HC12 m68hc11-elf
3904 UltraSparc running GNU/Linux sparc64-*-linux*
3906 * OBSOLETE configurations and files
3908 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3909 Harris/CXUX m88k m88*-harris-cxux*
3910 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3911 ns32k-utek-sysv* ns32k-utek-*
3912 TI TMS320C80 tic80-*-*
3914 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3915 PowerPC Solaris powerpcle-*-solaris*
3916 PowerPC Windows NT powerpcle-*-cygwin32
3917 PowerPC Netware powerpc-*-netware*
3918 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3919 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3920 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3921 Apple Macintosh (MPW) host N/A
3923 stuff.c (Program to stuff files into a specially prepared space in kdb)
3924 kdb-start.c (Main loop for the standalone kernel debugger)
3926 Configurations that have been declared obsolete in this release have
3927 been commented out. Unless there is activity to revive these
3928 configurations, the next release of GDB will have their sources
3929 permanently REMOVED.
3931 * REMOVED configurations and files
3933 Altos 3068 m68*-altos-*
3934 Convex c1-*-*, c2-*-*
3936 ARM RISCix arm-*-* (as host)
3940 * GDB has been converted to ISO C.
3942 GDB's source code has been converted to ISO C. In particular, the
3943 sources are fully protoized, and rely on standard headers being
3948 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3950 * The MI enabled by default.
3952 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3953 revised and enabled by default. Packages which use GDB as a debugging
3954 engine behind a UI or another front end are encouraged to switch to
3955 using the GDB/MI interface, instead of the old annotations interface
3956 which is now deprecated.
3958 * Support for debugging Pascal programs.
3960 GDB now includes support for debugging Pascal programs. The following
3961 main features are supported:
3963 - Pascal-specific data types such as sets;
3965 - automatic recognition of Pascal sources based on file-name
3968 - Pascal-style display of data types, variables, and functions;
3970 - a Pascal expression parser.
3972 However, some important features are not yet supported.
3974 - Pascal string operations are not supported at all;
3976 - there are some problems with boolean types;
3978 - Pascal type hexadecimal constants are not supported
3979 because they conflict with the internal variables format;
3981 - support for Pascal objects and classes is not full yet;
3983 - unlike Pascal, GDB is case-sensitive for symbol names.
3985 * Changes in completion.
3987 Commands such as `shell', `run' and `set args', which pass arguments
3988 to inferior programs, now complete on file names, similar to what
3989 users expect at the shell prompt.
3991 Commands which accept locations, such as `disassemble', `print',
3992 `breakpoint', `until', etc. now complete on filenames as well as
3993 program symbols. Thus, if you type "break foob TAB", and the source
3994 files linked into the programs include `foobar.c', that file name will
3995 be one of the candidates for completion. However, file names are not
3996 considered for completion after you typed a colon that delimits a file
3997 name from a name of a function in that file, as in "break foo.c:bar".
3999 `set demangle-style' completes on available demangling styles.
4001 * New platform-independent commands:
4003 It is now possible to define a post-hook for a command as well as a
4004 hook that runs before the command. For more details, see the
4005 documentation of `hookpost' in the GDB manual.
4007 * Changes in GNU/Linux native debugging.
4009 Support for debugging multi-threaded programs has been completely
4010 revised for all platforms except m68k and sparc. You can now debug as
4011 many threads as your system allows you to have.
4013 Attach/detach is supported for multi-threaded programs.
4015 Support for SSE registers was added for x86. This doesn't work for
4016 multi-threaded programs though.
4018 * Changes in MIPS configurations.
4020 Multi-arch support is enabled for all MIPS configurations.
4022 GDB can now be built as native debugger on SGI Irix 6.x systems for
4023 debugging n32 executables. (Debugging 64-bit executables is not yet
4026 * Unified support for hardware watchpoints in all x86 configurations.
4028 Most (if not all) native x86 configurations support hardware-assisted
4029 breakpoints and watchpoints in a unified manner. This support
4030 implements debug register sharing between watchpoints, which allows to
4031 put a virtually infinite number of watchpoints on the same address,
4032 and also supports watching regions up to 16 bytes with several debug
4035 The new maintenance command `maintenance show-debug-regs' toggles
4036 debugging print-outs in functions that insert, remove, and test
4037 watchpoints and hardware breakpoints.
4039 * Changes in the DJGPP native configuration.
4041 New command ``info dos sysinfo'' displays assorted information about
4042 the CPU, OS, memory, and DPMI server.
4044 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4045 display information about segment descriptors stored in GDT, LDT, and
4048 New commands ``info dos pde'' and ``info dos pte'' display entries
4049 from Page Directory and Page Tables (for now works with CWSDPMI only).
4050 New command ``info dos address-pte'' displays the Page Table entry for
4051 a given linear address.
4053 GDB can now pass command lines longer than 126 characters to the
4054 program being debugged (requires an update to the libdbg.a library
4055 which is part of the DJGPP development kit).
4057 DWARF2 debug info is now supported.
4059 It is now possible to `step' and `next' through calls to `longjmp'.
4061 * Changes in documentation.
4063 All GDB documentation was converted to GFDL, the GNU Free
4064 Documentation License.
4066 Tracepoints-related commands are now fully documented in the GDB
4069 TUI, the Text-mode User Interface, is now documented in the manual.
4071 Tracepoints-related commands are now fully documented in the GDB
4074 The "GDB Internals" manual now has an index. It also includes
4075 documentation of `ui_out' functions, GDB coding standards, x86
4076 hardware watchpoints, and memory region attributes.
4078 * GDB's version number moved to ``version.in''
4080 The Makefile variable VERSION has been replaced by the file
4081 ``version.in''. People creating GDB distributions should update the
4082 contents of this file.
4086 GUD support is now a standard part of the EMACS distribution.
4088 *** Changes in GDB 5.0:
4090 * Improved support for debugging FP programs on x86 targets
4092 Unified and much-improved support for debugging floating-point
4093 programs on all x86 targets. In particular, ``info float'' now
4094 displays the FP registers in the same format on all x86 targets, with
4095 greater level of detail.
4097 * Improvements and bugfixes in hardware-assisted watchpoints
4099 It is now possible to watch array elements, struct members, and
4100 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4101 on x86 targets no longer erroneously trigger when the address is
4104 * Improvements in the native DJGPP version of GDB
4106 The distribution now includes all the scripts and auxiliary files
4107 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4108 machines ``out of the box''.
4110 The DJGPP version can now debug programs that use signals. It is
4111 possible to catch signals that happened in the debuggee, deliver
4112 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4113 would kill the program being debugged.) Programs that hook hardware
4114 interrupts (keyboard, timer, etc.) can also be debugged.
4116 It is now possible to debug DJGPP programs that redirect their
4117 standard handles or switch them to raw (as opposed to cooked) mode, or
4118 even close them. The command ``run < foo > bar'' works as expected,
4119 and ``info terminal'' reports useful information about the debuggee's
4120 terminal, including raw/cooked mode, redirection, etc.
4122 The DJGPP version now uses termios functions for console I/O, which
4123 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4126 DOS-style file names with drive letters are now fully supported by
4129 It is now possible to debug DJGPP programs that switch their working
4130 directory. It is also possible to rerun the debuggee any number of
4131 times without restarting GDB; thus, you can use the same setup,
4132 breakpoints, etc. for many debugging sessions.
4134 * New native configurations
4136 ARM GNU/Linux arm*-*-linux*
4137 PowerPC GNU/Linux powerpc-*-linux*
4141 Motorola MCore mcore-*-*
4142 x86 VxWorks i[3456]86-*-vxworks*
4143 PowerPC VxWorks powerpc-*-vxworks*
4144 TI TMS320C80 tic80-*-*
4146 * OBSOLETE configurations
4148 Altos 3068 m68*-altos-*
4149 Convex c1-*-*, c2-*-*
4151 ARM RISCix arm-*-* (as host)
4154 Configurations that have been declared obsolete will be commented out,
4155 but the code will be left in place. If there is no activity to revive
4156 these configurations before the next release of GDB, the sources will
4157 be permanently REMOVED.
4159 * Gould support removed
4161 Support for the Gould PowerNode and NP1 has been removed.
4163 * New features for SVR4
4165 On SVR4 native platforms (such as Solaris), if you attach to a process
4166 without first loading a symbol file, GDB will now attempt to locate and
4167 load symbols from the running process's executable file.
4169 * Many C++ enhancements
4171 C++ support has been greatly improved. Overload resolution now works properly
4172 in almost all cases. RTTI support is on the way.
4174 * Remote targets can connect to a sub-program
4176 A popen(3) style serial-device has been added. This device starts a
4177 sub-process (such as a stand-alone simulator) and then communicates
4178 with that. The sub-program to run is specified using the syntax
4179 ``|<program> <args>'' vis:
4181 (gdb) set remotedebug 1
4182 (gdb) target extended-remote |mn10300-elf-sim program-args
4184 * MIPS 64 remote protocol
4186 A long standing bug in the mips64 remote protocol where by GDB
4187 expected certain 32 bit registers (ex SR) to be transfered as 32
4188 instead of 64 bits has been fixed.
4190 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4191 added to provide backward compatibility with older versions of GDB.
4193 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4195 The command ``set remotebinarydownload'' command has been replaced by
4196 ``set remote X-packet''. Other commands in ``set remote'' family
4197 include ``set remote P-packet''.
4199 * Breakpoint commands accept ranges.
4201 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4202 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4203 ``tracepoint passcount'' also accepts a range of tracepoints.
4205 * ``apropos'' command added.
4207 The ``apropos'' command searches through command names and
4208 documentation strings, printing out matches, making it much easier to
4209 try to find a command that does what you are looking for.
4213 A new machine oriented interface (MI) has been added to GDB. This
4214 interface is designed for debug environments running GDB as a separate
4215 process. This is part of the long term libGDB project. See the
4216 "GDB/MI" chapter of the GDB manual for further information. It can be
4217 enabled by configuring with:
4219 .../configure --enable-gdbmi
4221 *** Changes in GDB-4.18:
4223 * New native configurations
4225 HP-UX 10.20 hppa*-*-hpux10.20
4226 HP-UX 11.x hppa*-*-hpux11.0*
4227 M68K GNU/Linux m68*-*-linux*
4231 Fujitsu FR30 fr30-*-elf*
4232 Intel StrongARM strongarm-*-*
4233 Mitsubishi D30V d30v-*-*
4235 * OBSOLETE configurations
4237 Gould PowerNode, NP1 np1-*-*, pn-*-*
4239 Configurations that have been declared obsolete will be commented out,
4240 but the code will be left in place. If there is no activity to revive
4241 these configurations before the next release of GDB, the sources will
4242 be permanently REMOVED.
4246 As a compatibility experiment, GDB's source files buildsym.h and
4247 buildsym.c have been converted to pure standard C, no longer
4248 containing any K&R compatibility code. We believe that all systems in
4249 use today either come with a standard C compiler, or have a GCC port
4250 available. If this is not true, please report the affected
4251 configuration to bug-gdb@gnu.org immediately. See the README file for
4252 information about getting a standard C compiler if you don't have one
4257 GDB now uses readline 2.2.
4259 * set extension-language
4261 You can now control the mapping between filename extensions and source
4262 languages by using the `set extension-language' command. For instance,
4263 you can ask GDB to treat .c files as C++ by saying
4264 set extension-language .c c++
4265 The command `info extensions' lists all of the recognized extensions
4266 and their associated languages.
4268 * Setting processor type for PowerPC and RS/6000
4270 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4271 you can use the `set processor' command to specify what variant of the
4272 PowerPC family you are debugging. The command
4276 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4277 following PowerPC and RS6000 variants:
4279 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4280 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4282 403GC IBM PowerPC 403GC
4283 505 Motorola PowerPC 505
4284 860 Motorola PowerPC 860 or 850
4285 601 Motorola PowerPC 601
4286 602 Motorola PowerPC 602
4287 603 Motorola/IBM PowerPC 603 or 603e
4288 604 Motorola PowerPC 604 or 604e
4289 750 Motorola/IBM PowerPC 750 or 750
4291 At the moment, this command just tells GDB what to name the
4292 special-purpose processor registers. Since almost all the affected
4293 registers are inaccessible to user-level programs, this command is
4294 only useful for remote debugging in its present form.
4298 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4299 more extensive support for HP-UX. Added features include shared
4300 library support, kernel threads and hardware watchpoints for 11.00,
4301 support for HP's ANSI C and C++ compilers, and a compatibility mode
4302 for xdb and dbx commands.
4306 HP's donation includes the new concept of catchpoints, which is a
4307 generalization of the old catch command. On HP-UX, it is now possible
4308 to catch exec, fork, and vfork, as well as library loading.
4310 This means that the existing catch command has changed; its first
4311 argument now specifies the type of catch to be set up. See the
4312 output of "help catch" for a list of catchpoint types.
4314 * Debugging across forks
4316 On HP-UX, you can choose which process to debug when a fork() happens
4321 HP has donated a curses-based terminal user interface (TUI). To get
4322 it, build with --enable-tui. Although this can be enabled for any
4323 configuration, at present it only works for native HP debugging.
4325 * GDB remote protocol additions
4327 A new protocol packet 'X' that writes binary data is now available.
4328 Default behavior is to try 'X', then drop back to 'M' if the stub
4329 fails to respond. The settable variable `remotebinarydownload'
4330 allows explicit control over the use of 'X'.
4332 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4333 full 64-bit address. The command
4335 set remoteaddresssize 32
4337 can be used to revert to the old behaviour. For existing remote stubs
4338 the change should not be noticed, as the additional address information
4341 In order to assist in debugging stubs, you may use the maintenance
4342 command `packet' to send any text string to the stub. For instance,
4344 maint packet heythere
4346 sends the packet "$heythere#<checksum>". Note that it is very easy to
4347 disrupt a debugging session by sending the wrong packet at the wrong
4350 The compare-sections command allows you to compare section data on the
4351 target to what is in the executable file without uploading or
4352 downloading, by comparing CRC checksums.
4354 * Tracing can collect general expressions
4356 You may now collect general expressions at tracepoints. This requires
4357 further additions to the target-side stub; see tracepoint.c and
4358 doc/agentexpr.texi for further details.
4360 * mask-address variable for Mips
4362 For Mips targets, you may control the zeroing of the upper 32 bits of
4363 a 64-bit address by entering `set mask-address on'. This is mainly
4364 of interest to users of embedded R4xxx and R5xxx processors.
4366 * Higher serial baud rates
4368 GDB's serial code now allows you to specify baud rates 57600, 115200,
4369 230400, and 460800 baud. (Note that your host system may not be able
4370 to achieve all of these rates.)
4374 The i960 configuration now includes an initial implementation of a
4375 builtin simulator, contributed by Jim Wilson.
4378 *** Changes in GDB-4.17:
4380 * New native configurations
4382 Alpha GNU/Linux alpha*-*-linux*
4383 Unixware 2.x i[3456]86-unixware2*
4384 Irix 6.x mips*-sgi-irix6*
4385 PowerPC GNU/Linux powerpc-*-linux*
4386 PowerPC Solaris powerpcle-*-solaris*
4387 Sparc GNU/Linux sparc-*-linux*
4388 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4392 Argonaut Risc Chip (ARC) arc-*-*
4393 Hitachi H8/300S h8300*-*-*
4394 Matsushita MN10200 w/simulator mn10200-*-*
4395 Matsushita MN10300 w/simulator mn10300-*-*
4396 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4397 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4398 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4399 Mitsubishi D10V w/simulator d10v-*-*
4400 Mitsubishi M32R/D w/simulator m32r-*-elf*
4401 Tsqware Sparclet sparclet-*-*
4402 NEC V850 w/simulator v850-*-*
4404 * New debugging protocols
4406 ARM with RDI protocol arm*-*-*
4407 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4408 DDB and LSI variants of PMON protocol mips*-*-*
4409 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4410 PowerPC with SDS protocol powerpc{,le}-*-eabi
4411 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4415 All configurations can now understand and use the DWARF 2 debugging
4416 format. The choice is automatic, if the symbol file contains DWARF 2
4421 GDB now includes basic Java language support. This support is
4422 only useful with Java compilers that produce native machine code.
4424 * solib-absolute-prefix and solib-search-path
4426 For SunOS and SVR4 shared libraries, you may now set the prefix for
4427 loading absolute shared library symbol files, and the search path for
4428 locating non-absolute shared library symbol files.
4430 * Live range splitting
4432 GDB can now effectively debug code for which GCC has performed live
4433 range splitting as part of its optimization. See gdb/doc/LRS for
4434 more details on the expected format of the stabs information.
4438 GDB's support for the GNU Hurd, including thread debugging, has been
4439 updated to work with current versions of the Hurd.
4443 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4444 instruction set. ARM GDB automatically detects when Thumb
4445 instructions are in use, and adjusts disassembly and backtracing
4450 GDB's MIPS target configurations now handle the MIP16 16-bit
4455 GDB now includes support for overlays; if an executable has been
4456 linked such that multiple sections are based at the same address, GDB
4457 will decide which section to use for symbolic info. You can choose to
4458 control the decision manually, using overlay commands, or implement
4459 additional target-side support and use "overlay load-target" to bring
4460 in the overlay mapping. Do "help overlay" for more detail.
4464 The command "info symbol <address>" displays information about
4465 the symbol at the specified address.
4469 The standard remote protocol now includes an extension that allows
4470 asynchronous collection and display of trace data. This requires
4471 extensive support in the target-side debugging stub. Tracing mode
4472 includes a new interaction mode in GDB and new commands: see the
4473 file tracepoint.c for more details.
4477 Configurations for embedded MIPS now include a simulator contributed
4478 by Cygnus Solutions. The simulator supports the instruction sets
4479 of most MIPS variants.
4483 Sparc configurations may now include the ERC32 simulator contributed
4484 by the European Space Agency. The simulator is not built into
4485 Sparc targets by default; configure with --enable-sim to include it.
4489 For target configurations that may include multiple variants of a
4490 basic architecture (such as MIPS and SH), you may now set the
4491 architecture explicitly. "set arch" sets, "info arch" lists
4492 the possible architectures.
4494 *** Changes in GDB-4.16:
4496 * New native configurations
4498 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4499 M68K NetBSD m68k-*-netbsd*
4500 PowerPC AIX 4.x powerpc-*-aix*
4501 PowerPC MacOS powerpc-*-macos*
4502 PowerPC Windows NT powerpcle-*-cygwin32
4503 RS/6000 AIX 4.x rs6000-*-aix4*
4507 ARM with RDP protocol arm-*-*
4508 I960 with MON960 i960-*-coff
4509 MIPS VxWorks mips*-*-vxworks*
4510 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4511 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4513 Matra Sparclet sparclet-*-*
4517 The powerpc-eabi configuration now includes the PSIM simulator,
4518 contributed by Andrew Cagney, with assistance from Mike Meissner.
4519 PSIM is a very elaborate model of the PowerPC, including not only
4520 basic instruction set execution, but also details of execution unit
4521 performance and I/O hardware. See sim/ppc/README for more details.
4525 GDB now works with Solaris 2.5.
4527 * Windows 95/NT native
4529 GDB will now work as a native debugger on Windows 95 and Windows NT.
4530 To build it from source, you must use the "gnu-win32" environment,
4531 which uses a DLL to emulate enough of Unix to run the GNU tools.
4532 Further information, binaries, and sources are available at
4533 ftp.cygnus.com, under pub/gnu-win32.
4535 * dont-repeat command
4537 If a user-defined command includes the command `dont-repeat', then the
4538 command will not be repeated if the user just types return. This is
4539 useful if the command is time-consuming to run, so that accidental
4540 extra keystrokes don't run the same command many times.
4542 * Send break instead of ^C
4544 The standard remote protocol now includes an option to send a break
4545 rather than a ^C to the target in order to interrupt it. By default,
4546 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4548 * Remote protocol timeout
4550 The standard remote protocol includes a new variable `remotetimeout'
4551 that allows you to set the number of seconds before GDB gives up trying
4552 to read from the target. The default value is 2.
4554 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4556 By default GDB will automatically keep track of objects as they are
4557 loaded and unloaded by the dynamic linker. By using the command `set
4558 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4559 when shared library events occur, thus allowing you to set breakpoints
4560 in shared libraries which are explicitly loaded by the inferior.
4562 Note this feature does not work on hpux8. On hpux9 you must link
4563 /usr/lib/end.o into your program. This feature should work
4564 automatically on hpux10.
4566 * Irix 5.x hardware watchpoint support
4568 Irix 5 configurations now support the use of hardware watchpoints.
4570 * Mips protocol "SYN garbage limit"
4572 When debugging a Mips target using the `target mips' protocol, you
4573 may set the number of characters that GDB will ignore by setting
4574 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4575 every character. The default value is 1050.
4577 * Recording and replaying remote debug sessions
4579 If you set `remotelogfile' to the name of a file, gdb will write to it
4580 a recording of a remote debug session. This recording may then be
4581 replayed back to gdb using "gdbreplay". See gdbserver/README for
4582 details. This is useful when you have a problem with GDB while doing
4583 remote debugging; you can make a recording of the session and send it
4584 to someone else, who can then recreate the problem.
4586 * Speedups for remote debugging
4588 GDB includes speedups for downloading and stepping MIPS systems using
4589 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4590 and more efficient S-record downloading.
4592 * Memory use reductions and statistics collection
4594 GDB now uses less memory and reports statistics about memory usage.
4595 Try the `maint print statistics' command, for example.
4597 *** Changes in GDB-4.15:
4599 * Psymtabs for XCOFF
4601 The symbol reader for AIX GDB now uses partial symbol tables. This
4602 can greatly improve startup time, especially for large executables.
4604 * Remote targets use caching
4606 Remote targets now use a data cache to speed up communication with the
4607 remote side. The data cache could lead to incorrect results because
4608 it doesn't know about volatile variables, thus making it impossible to
4609 debug targets which use memory mapped I/O devices. `set remotecache
4610 off' turns the the data cache off.
4612 * Remote targets may have threads
4614 The standard remote protocol now includes support for multiple threads
4615 in the target system, using new protocol commands 'H' and 'T'. See
4616 gdb/remote.c for details.
4620 If GDB is configured with `--enable-netrom', then it will include
4621 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4622 acts as though it is a bank of ROM on the target board, but you can
4623 write into it over the network. GDB's support consists only of
4624 support for fast loading into the emulated ROM; to debug, you must use
4625 another protocol, such as standard remote protocol. The usual
4626 sequence is something like
4628 target nrom <netrom-hostname>
4630 target remote <netrom-hostname>:1235
4634 GDB now includes support for the Apple Macintosh, as a host only. It
4635 may be run as either an MPW tool or as a standalone application, and
4636 it can debug through the serial port. All the usual GDB commands are
4637 available, but to the target command, you must supply "serial" as the
4638 device type instead of "/dev/ttyXX". See mpw-README in the main
4639 directory for more information on how to build. The MPW configuration
4640 scripts */mpw-config.in support only a few targets, and only the
4641 mips-idt-ecoff target has been tested.
4645 GDB configuration now uses autoconf. This is not user-visible,
4646 but does simplify configuration and building.
4650 GDB now supports hpux10.
4652 *** Changes in GDB-4.14:
4654 * New native configurations
4656 x86 FreeBSD i[345]86-*-freebsd
4657 x86 NetBSD i[345]86-*-netbsd
4658 NS32k NetBSD ns32k-*-netbsd
4659 Sparc NetBSD sparc-*-netbsd
4663 A29K VxWorks a29k-*-vxworks
4664 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4665 CPU32 EST-300 emulator m68*-*-est*
4666 PowerPC ELF powerpc-*-elf
4669 * Alpha OSF/1 support for procfs
4671 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4672 possible to attach to running processes. As the mounting of the /proc
4673 filesystem is optional on the Alpha, GDB automatically determines
4674 the availability of /proc during startup. This can lead to problems
4675 if /proc is unmounted after GDB has been started.
4677 * Arguments to user-defined commands
4679 User commands may accept up to 10 arguments separated by whitespace.
4680 Arguments are accessed within the user command via $arg0..$arg9. A
4683 print $arg0 + $arg1 + $arg2
4685 To execute the command use:
4688 Defines the command "adder" which prints the sum of its three arguments.
4689 Note the arguments are text substitutions, so they may reference variables,
4690 use complex expressions, or even perform inferior function calls.
4692 * New `if' and `while' commands
4694 This makes it possible to write more sophisticated user-defined
4695 commands. Both commands take a single argument, which is the
4696 expression to evaluate, and must be followed by the commands to
4697 execute, one per line, if the expression is nonzero, the list being
4698 terminated by the word `end'. The `if' command list may include an
4699 `else' word, which causes the following commands to be executed only
4700 if the expression is zero.
4702 * Fortran source language mode
4704 GDB now includes partial support for Fortran 77. It will recognize
4705 Fortran programs and can evaluate a subset of Fortran expressions, but
4706 variables and functions may not be handled correctly. GDB will work
4707 with G77, but does not yet know much about symbols emitted by other
4710 * Better HPUX support
4712 Most debugging facilities now work on dynamic executables for HPPAs
4713 running hpux9 or later. You can attach to running dynamically linked
4714 processes, but by default the dynamic libraries will be read-only, so
4715 for instance you won't be able to put breakpoints in them. To change
4716 that behavior do the following before running the program:
4722 This will cause the libraries to be mapped private and read-write.
4723 To revert to the normal behavior, do this:
4729 You cannot set breakpoints or examine data in the library until after
4730 the library is loaded if the function/data symbols do not have
4733 GDB can now also read debug symbols produced by the HP C compiler on
4734 HPPAs (sorry, no C++, Fortran or 68k support).
4736 * Target byte order now dynamically selectable
4738 You can choose which byte order to use with a target system, via the
4739 commands "set endian big" and "set endian little", and you can see the
4740 current setting by using "show endian". You can also give the command
4741 "set endian auto", in which case GDB will use the byte order
4742 associated with the executable. Currently, only embedded MIPS
4743 configurations support dynamic selection of target byte order.
4745 * New DOS host serial code
4747 This version uses DPMI interrupts to handle buffered I/O, so you
4748 no longer need to run asynctsr when debugging boards connected to
4751 *** Changes in GDB-4.13:
4753 * New "complete" command
4755 This lists all the possible completions for the rest of the line, if it
4756 were to be given as a command itself. This is intended for use by emacs.
4758 * Trailing space optional in prompt
4760 "set prompt" no longer adds a space for you after the prompt you set. This
4761 allows you to set a prompt which ends in a space or one that does not.
4763 * Breakpoint hit counts
4765 "info break" now displays a count of the number of times the breakpoint
4766 has been hit. This is especially useful in conjunction with "ignore"; you
4767 can ignore a large number of breakpoint hits, look at the breakpoint info
4768 to see how many times the breakpoint was hit, then run again, ignoring one
4769 less than that number, and this will get you quickly to the last hit of
4772 * Ability to stop printing at NULL character
4774 "set print null-stop" will cause GDB to stop printing the characters of
4775 an array when the first NULL is encountered. This is useful when large
4776 arrays actually contain only short strings.
4778 * Shared library breakpoints
4780 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4781 breakpoints in shared libraries before the executable is run.
4783 * Hardware watchpoints
4785 There is a new hardware breakpoint for the watch command for sparclite
4786 targets. See gdb/sparclite/hw_breakpoint.note.
4788 Hardware watchpoints are also now supported under GNU/Linux.
4792 Annotations have been added. These are for use with graphical interfaces,
4793 and are still experimental. Currently only gdba.el uses these.
4795 * Improved Irix 5 support
4797 GDB now works properly with Irix 5.2.
4799 * Improved HPPA support
4801 GDB now works properly with the latest GCC and GAS.
4803 * New native configurations
4805 Sequent PTX4 i[34]86-sequent-ptx4
4806 HPPA running OSF/1 hppa*-*-osf*
4807 Atari TT running SVR4 m68*-*-sysv4*
4808 RS/6000 LynxOS rs6000-*-lynxos*
4812 OS/9000 i[34]86-*-os9k
4813 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4816 * Hitachi SH7000 and E7000-PC ICE support
4818 There is now support for communicating with the Hitachi E7000-PC ICE.
4819 This is available automatically when GDB is configured for the SH.
4823 As usual, a variety of small fixes and improvements, both generic
4824 and configuration-specific. See the ChangeLog for more detail.
4826 *** Changes in GDB-4.12:
4828 * Irix 5 is now supported
4832 GDB-4.12 on the HPPA has a number of changes which make it unable
4833 to debug the output from the currently released versions of GCC and
4834 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4835 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4836 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4839 *** Changes in GDB-4.11:
4841 * User visible changes:
4845 The "set remotedebug" option is now consistent between the mips remote
4846 target, remote targets using the gdb-specific protocol, UDI (AMD's
4847 debug protocol for the 29k) and the 88k bug monitor. It is now an
4848 integer specifying a debug level (normally 0 or 1, but 2 means more
4849 debugging info for the mips target).
4851 * DEC Alpha native support
4853 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4854 debug info, but GDB works fairly well with the DEC compiler and should
4855 work with a future GCC release. See the README file for a few
4856 Alpha-specific notes.
4858 * Preliminary thread implementation
4860 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4862 * LynxOS native and target support for 386
4864 This release has been hosted on LynxOS 2.2, and also can be configured
4865 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4868 * Improvements in C++ mangling/demangling.
4870 This release has much better g++ debugging, specifically in name
4871 mangling/demangling, virtual function calls, print virtual table,
4872 call methods, ...etc.
4874 *** Changes in GDB-4.10:
4876 * User visible changes:
4878 Remote debugging using the GDB-specific (`target remote') protocol now
4879 supports the `load' command. This is only useful if you have some
4880 other way of getting the stub to the target system, and you can put it
4881 somewhere in memory where it won't get clobbered by the download.
4883 Filename completion now works.
4885 When run under emacs mode, the "info line" command now causes the
4886 arrow to point to the line specified. Also, "info line" prints
4887 addresses in symbolic form (as well as hex).
4889 All vxworks based targets now support a user settable option, called
4890 vxworks-timeout. This option represents the number of seconds gdb
4891 should wait for responses to rpc's. You might want to use this if
4892 your vxworks target is, perhaps, a slow software simulator or happens
4893 to be on the far side of a thin network line.
4897 This release contains support for using a DEC alpha as a GDB host for
4898 cross debugging. Native alpha debugging is not supported yet.
4901 *** Changes in GDB-4.9:
4905 This is the first GDB release which is accompanied by a matching testsuite.
4906 The testsuite requires installation of dejagnu, which should be available
4907 via ftp from most sites that carry GNU software.
4911 'Cfront' style demangling has had its name changed to 'ARM' style, to
4912 emphasize that it was written from the specifications in the C++ Annotated
4913 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4914 disclaimers, it still generated too much confusion with users attempting to
4915 use gdb with AT&T cfront.
4919 GDB now uses a standard remote interface to a simulator library.
4920 So far, the library contains simulators for the Zilog Z8001/2, the
4921 Hitachi H8/300, H8/500 and Super-H.
4923 * New targets supported
4925 H8/300 simulator h8300-hitachi-hms or h8300hms
4926 H8/500 simulator h8500-hitachi-hms or h8500hms
4927 SH simulator sh-hitachi-hms or sh
4928 Z8000 simulator z8k-zilog-none or z8ksim
4929 IDT MIPS board over serial line mips-idt-ecoff
4931 Cross-debugging to GO32 targets is supported. It requires a custom
4932 version of the i386-stub.c module which is integrated with the
4933 GO32 memory extender.
4935 * New remote protocols
4937 MIPS remote debugging protocol.
4939 * New source languages supported
4941 This version includes preliminary support for Chill, a Pascal like language
4942 used by telecommunications companies. Chill support is also being integrated
4943 into the GNU compiler, but we don't know when it will be publically available.
4946 *** Changes in GDB-4.8:
4948 * HP Precision Architecture supported
4950 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4951 version of this support was available as a set of patches from the
4952 University of Utah. GDB does not support debugging of programs
4953 compiled with the HP compiler, because HP will not document their file
4954 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4955 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4957 Many problems in the preliminary version have been fixed.
4959 * Faster and better demangling
4961 We have improved template demangling and fixed numerous bugs in the GNU style
4962 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4963 character types (wchar_t) are now supported. Demangling of each symbol is now
4964 only done once, and is cached when the symbol table for a file is read in.
4965 This results in a small increase in memory usage for C programs, a moderate
4966 increase in memory usage for C++ programs, and a fantastic speedup in
4969 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4970 from the specifications in the Annotated Reference Manual, which AT&T's
4971 compiler does not actually implement.
4973 * G++ multiple inheritance compiler problem
4975 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4976 inheritance lattices was reworked to properly discover ambiguities. We
4977 recently found an example which causes this new algorithm to fail in a
4978 very subtle way, producing bad debug information for those classes.
4979 The file 'gcc.patch' (in this directory) can be applied to gcc to
4980 circumvent the problem. A future GCC release will contain a complete
4983 The previous G++ debug info problem (mentioned below for the gdb-4.7
4984 release) is fixed in gcc version 2.3.2.
4986 * Improved configure script
4988 The `configure' script will now attempt to guess your system type if
4989 you don't supply a host system type. The old scheme of supplying a
4990 host system triplet is preferable over using this. All the magic is
4991 done in the new `config.guess' script. Examine it for details.
4993 We have also brought our configure script much more in line with the FSF's
4994 version. It now supports the --with-xxx options. In particular,
4995 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4996 The resulting GDB will not be able to read arbitrary object file formats --
4997 only the format ``expected'' to be used on the configured target system.
4998 We hope to make this the default in a future release.
5000 * Documentation improvements
5002 There's new internal documentation on how to modify GDB, and how to
5003 produce clean changes to the code. We implore people to read it
5004 before submitting changes.
5006 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5007 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5008 `info' files are also provided. To build `info' files from scratch,
5009 you will need the latest `makeinfo' release, which will be available in
5010 a future texinfo-X.Y release.
5012 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5013 We're not sure exactly which versions have this problem, but it has
5014 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5015 or better. If that isn't possible, there is a patch in
5016 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5017 around this problem.
5021 GDB now supports array constants that can be used in expressions typed in by
5022 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5023 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5026 The new directory `gdb/sparclite' contains a program that demonstrates
5027 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5029 * New native hosts supported
5031 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5032 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5034 * New targets supported
5036 AMD 29k family via UDI a29k-amd-udi or udi29k
5038 * New file formats supported
5040 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5041 HPUX core files, and SCO 3.2v2 core files.
5045 Attaching to processes now works again; thanks for the many bug reports.
5047 We have also stomped on a bunch of core dumps caused by
5048 printf_filtered("%s") problems.
5050 We eliminated a copyright problem on the rpc and ptrace header files
5051 for VxWorks, which was discovered at the last minute during the 4.7
5052 release. You should now be able to build a VxWorks GDB.
5054 You can now interrupt gdb while an attached process is running. This
5055 will cause the attached process to stop, and give control back to GDB.
5057 We fixed problems caused by using too many file descriptors
5058 for reading symbols from object files and libraries. This was
5059 especially a problem for programs that used many (~100) shared
5062 The `step' command now only enters a subroutine if there is line number
5063 information for the subroutine. Otherwise it acts like the `next'
5064 command. Previously, `step' would enter subroutines if there was
5065 any debugging information about the routine. This avoids problems
5066 when using `cc -g1' on MIPS machines.
5068 * Internal improvements
5070 GDB's internal interfaces have been improved to make it easier to support
5071 debugging of multiple languages in the future.
5073 GDB now uses a common structure for symbol information internally.
5074 Minimal symbols (derived from linkage symbols in object files), partial
5075 symbols (from a quick scan of debug information), and full symbols
5076 contain a common subset of information, making it easier to write
5077 shared code that handles any of them.
5079 * New command line options
5081 We now accept --silent as an alias for --quiet.
5085 The memory-mapped-malloc library is now licensed under the GNU Library
5086 General Public License.
5088 *** Changes in GDB-4.7:
5090 * Host/native/target split
5092 GDB has had some major internal surgery to untangle the support for
5093 hosts and remote targets. Now, when you configure GDB for a remote
5094 target, it will no longer load in all of the support for debugging
5095 local programs on the host. When fully completed and tested, this will
5096 ensure that arbitrary host/target combinations are possible.
5098 The primary conceptual shift is to separate the non-portable code in
5099 GDB into three categories. Host specific code is required any time GDB
5100 is compiled on that host, regardless of the target. Target specific
5101 code relates to the peculiarities of the target, but can be compiled on
5102 any host. Native specific code is everything else: it can only be
5103 built when the host and target are the same system. Child process
5104 handling and core file support are two common `native' examples.
5106 GDB's use of /proc for controlling Unix child processes is now cleaner.
5107 It has been split out into a single module under the `target_ops' vector,
5108 plus two native-dependent functions for each system that uses /proc.
5110 * New hosts supported
5112 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5113 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5114 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5116 * New targets supported
5118 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5119 68030 and CPU32 m68030-*-*, m68332-*-*
5121 * New native hosts supported
5123 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5124 (386bsd is not well tested yet)
5125 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5127 * New file formats supported
5129 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5130 supports reading of `a.out.adobe' object files, which are an a.out
5131 format extended with minimal information about multiple sections.
5135 `show copying' is the same as the old `info copying'.
5136 `show warranty' is the same as `info warrantee'.
5137 These were renamed for consistency. The old commands continue to work.
5139 `info handle' is a new alias for `info signals'.
5141 You can now define pre-command hooks, which attach arbitrary command
5142 scripts to any command. The commands in the hook will be executed
5143 prior to the user's command. You can also create a hook which will be
5144 executed whenever the program stops. See gdb.texinfo.
5148 We now deal with Cfront style name mangling, and can even extract type
5149 info from mangled symbols. GDB can automatically figure out which
5150 symbol mangling style your C++ compiler uses.
5152 Calling of methods and virtual functions has been improved as well.
5156 The crash that occured when debugging Sun Ansi-C compiled binaries is
5157 fixed. This was due to mishandling of the extra N_SO stabs output
5160 We also finally got Ultrix 4.2 running in house, and fixed core file
5161 support, with help from a dozen people on the net.
5163 John M. Farrell discovered that the reason that single-stepping was so
5164 slow on all of the Mips based platforms (primarily SGI and DEC) was
5165 that we were trying to demangle and lookup a symbol used for internal
5166 purposes on every instruction that was being stepped through. Changing
5167 the name of that symbol so that it couldn't be mistaken for a C++
5168 mangled symbol sped things up a great deal.
5170 Rich Pixley sped up symbol lookups in general by getting much smarter
5171 about when C++ symbol mangling is necessary. This should make symbol
5172 completion (TAB on the command line) much faster. It's not as fast as
5173 we'd like, but it's significantly faster than gdb-4.6.
5177 A new user controllable variable 'call_scratch_address' can
5178 specify the location of a scratch area to be used when GDB
5179 calls a function in the target. This is necessary because the
5180 usual method of putting the scratch area on the stack does not work
5181 in systems that have separate instruction and data spaces.
5183 We integrated changes to support the 29k UDI (Universal Debugger
5184 Interface), but discovered at the last minute that we didn't have all
5185 of the appropriate copyright paperwork. We are working with AMD to
5186 resolve this, and hope to have it available soon.
5190 We have sped up the remote serial line protocol, especially for targets
5191 with lots of registers. It now supports a new `expedited status' ('T')
5192 message which can be used in place of the existing 'S' status message.
5193 This allows the remote stub to send only the registers that GDB
5194 needs to make a quick decision about single-stepping or conditional
5195 breakpoints, eliminating the need to fetch the entire register set for
5196 each instruction being stepped through.
5198 The GDB remote serial protocol now implements a write-through cache for
5199 registers, only re-reading the registers if the target has run.
5201 There is also a new remote serial stub for SPARC processors. You can
5202 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5203 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5204 processor with a serial port.
5208 Configure.in files have become much easier to read and modify. A new
5209 `table driven' format makes it more obvious what configurations are
5210 supported, and what files each one uses.
5214 There is a new opcodes library which will eventually contain all of the
5215 disassembly routines and opcode tables. At present, it only contains
5216 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5217 disassembler (binutils/objdump) to share these routines.
5219 The libiberty library is now copylefted under the GNU Library General
5220 Public License. This allows more liberal use, and was done so libg++
5221 can use it. This makes no difference to GDB, since the Library License
5222 grants all the rights from the General Public License.
5226 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5227 reference to the stabs symbol info used by the debugger. It is (as far
5228 as we know) the only published document on this fascinating topic. We
5229 encourage you to read it, compare it to the stabs information on your
5230 system, and send improvements on the document in general (to
5231 bug-gdb@prep.ai.mit.edu).
5233 And, of course, many bugs have been fixed.
5236 *** Changes in GDB-4.6:
5238 * Better support for C++ function names
5240 GDB now accepts as input the "demangled form" of C++ overloaded function
5241 names and member function names, and can do command completion on such names
5242 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5243 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5244 Make use of command completion, it is your friend.
5246 GDB also now accepts a variety of C++ mangled symbol formats. They are
5247 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5248 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5249 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5250 for the list of formats.
5252 * G++ symbol mangling problem
5254 Recent versions of gcc have a bug in how they emit debugging information for
5255 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5256 directory) can be applied to gcc to fix the problem. Alternatively, if you
5257 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5258 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5259 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5262 * New 'maintenance' command
5264 All of the commands related to hacking GDB internals have been moved out of
5265 the main command set, and now live behind the 'maintenance' command. This
5266 can also be abbreviated as 'mt'. The following changes were made:
5268 dump-me -> maintenance dump-me
5269 info all-breakpoints -> maintenance info breakpoints
5270 printmsyms -> maintenance print msyms
5271 printobjfiles -> maintenance print objfiles
5272 printpsyms -> maintenance print psymbols
5273 printsyms -> maintenance print symbols
5275 The following commands are new:
5277 maintenance demangle Call internal GDB demangler routine to
5278 demangle a C++ link name and prints the result.
5279 maintenance print type Print a type chain for a given symbol
5281 * Change to .gdbinit file processing
5283 We now read the $HOME/.gdbinit file before processing the argv arguments
5284 (e.g. reading symbol files or core files). This allows global parameters to
5285 be set, which will apply during the symbol reading. The ./.gdbinit is still
5286 read after argv processing.
5288 * New hosts supported
5290 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5292 GNU/Linux support i386-unknown-linux or linux
5294 We are also including code to support the HP/PA running BSD and HPUX. This
5295 is almost guaranteed not to work, as we didn't have time to test or build it
5296 for this release. We are including it so that the more adventurous (or
5297 masochistic) of you can play with it. We also had major problems with the
5298 fact that the compiler that we got from HP doesn't support the -g option.
5301 * New targets supported
5303 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5305 * More smarts about finding #include files
5307 GDB now remembers the compilation directory for all include files, and for
5308 all files from which C is generated (like yacc and lex sources). This
5309 greatly improves GDB's ability to find yacc/lex sources, and include files,
5310 especially if you are debugging your program from a directory different from
5311 the one that contains your sources.
5313 We also fixed a bug which caused difficulty with listing and setting
5314 breakpoints in include files which contain C code. (In the past, you had to
5315 try twice in order to list an include file that you hadn't looked at before.)
5317 * Interesting infernals change
5319 GDB now deals with arbitrary numbers of sections, where the symbols for each
5320 section must be relocated relative to that section's landing place in the
5321 target's address space. This work was needed to support ELF with embedded
5322 stabs used by Solaris-2.0.
5324 * Bug fixes (of course!)
5326 There have been loads of fixes for the following things:
5327 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5328 i960, stabs, DOS(GO32), procfs, etc...
5330 See the ChangeLog for details.
5332 *** Changes in GDB-4.5:
5334 * New machines supported (host and target)
5336 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5338 SGI Irix-4.x mips-sgi-irix4 or iris4
5340 * New malloc package
5342 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5343 Mmalloc is capable of handling mutiple heaps of memory. It is also
5344 capable of saving a heap to a file, and then mapping it back in later.
5345 This can be used to greatly speedup the startup of GDB by using a
5346 pre-parsed symbol table which lives in a mmalloc managed heap. For
5347 more details, please read mmalloc/mmalloc.texi.
5351 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5352 'help info proc' for details.
5354 * MIPS ecoff symbol table format
5356 The code that reads MIPS symbol table format is now supported on all hosts.
5357 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5360 * File name changes for MS-DOS
5362 Many files in the config directories have been renamed to make it easier to
5363 support GDB on MS-DOSe systems (which have very restrictive file name
5364 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5365 environment) is close to working but has some remaining problems. Note
5366 that debugging of DOS programs is not supported, due to limitations
5367 in the ``operating system'', but it can be used to host cross-debugging.
5369 * Cross byte order fixes
5371 Many fixes have been made to support cross debugging of Sparc and MIPS
5372 targets from hosts whose byte order differs.
5374 * New -mapped and -readnow options
5376 If memory-mapped files are available on your system through the 'mmap'
5377 system call, you can use the -mapped option on the `file' or
5378 `symbol-file' commands to cause GDB to write the symbols from your
5379 program into a reusable file. If the program you are debugging is
5380 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5381 Future GDB debugging sessions will notice the presence of this file,
5382 and will quickly map in symbol information from it, rather than reading
5383 the symbol table from the executable program. Using the '-mapped'
5384 option in a GDB `file' or `symbol-file' command has the same effect as
5385 starting GDB with the '-mapped' command-line option.
5387 You can cause GDB to read the entire symbol table immediately by using
5388 the '-readnow' option with any of the commands that load symbol table
5389 information (or on the GDB command line). This makes the command
5390 slower, but makes future operations faster.
5392 The -mapped and -readnow options are typically combined in order to
5393 build a `fred.syms' file that contains complete symbol information.
5394 A simple GDB invocation to do nothing but build a `.syms' file for future
5397 gdb -batch -nx -mapped -readnow programname
5399 The `.syms' file is specific to the host machine on which GDB is run.
5400 It holds an exact image of GDB's internal symbol table. It cannot be
5401 shared across multiple host platforms.
5403 * longjmp() handling
5405 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5406 siglongjmp() without losing control. This feature has not yet been ported to
5407 all systems. It currently works on many 386 platforms, all MIPS-based
5408 platforms (SGI, DECstation, etc), and Sun3/4.
5412 Preliminary work has been put in to support the new Solaris OS from Sun. At
5413 this time, it can control and debug processes, but it is not capable of
5418 As always, many many bug fixes. The major areas were with g++, and mipsread.
5419 People using the MIPS-based platforms should experience fewer mysterious
5420 crashes and trashed symbol tables.
5422 *** Changes in GDB-4.4:
5424 * New machines supported (host and target)
5426 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5428 BSD Reno on Vax vax-dec-bsd
5429 Ultrix on Vax vax-dec-ultrix
5431 * New machines supported (target)
5433 AMD 29000 embedded, using EBMON a29k-none-none
5437 GDB continues to improve its handling of C++. `References' work better.
5438 The demangler has also been improved, and now deals with symbols mangled as
5439 per the Annotated C++ Reference Guide.
5441 GDB also now handles `stabs' symbol information embedded in MIPS
5442 `ecoff' symbol tables. Since the ecoff format was not easily
5443 extensible to handle new languages such as C++, this appeared to be a
5444 good way to put C++ debugging info into MIPS binaries. This option
5445 will be supported in the GNU C compiler, version 2, when it is
5448 * New features for SVR4
5450 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5451 shared libraries. Debugging dynamically linked programs should present
5452 only minor differences from debugging statically linked programs.
5454 The `info proc' command will print out information about any process
5455 on an SVR4 system (including the one you are debugging). At the moment,
5456 it prints the address mappings of the process.
5458 If you bring up GDB on another SVR4 system, please send mail to
5459 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5461 * Better dynamic linking support in SunOS
5463 Reading symbols from shared libraries which contain debugging symbols
5464 now works properly. However, there remain issues such as automatic
5465 skipping of `transfer vector' code during function calls, which
5466 make it harder to debug code in a shared library, than to debug the
5467 same code linked statically.
5471 GDB is now using the latest `getopt' routines from the FSF. This
5472 version accepts the -- prefix for options with long names. GDB will
5473 continue to accept the old forms (-option and +option) as well.
5474 Various single letter abbreviations for options have been explicity
5475 added to the option table so that they won't get overshadowed in the
5476 future by other options that begin with the same letter.
5480 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5481 Many assorted bugs have been handled. Many more remain to be handled.
5482 See the various ChangeLog files (primarily in gdb and bfd) for details.
5485 *** Changes in GDB-4.3:
5487 * New machines supported (host and target)
5489 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5490 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5491 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5493 * Almost SCO Unix support
5495 We had hoped to support:
5496 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5497 (except for core file support), but we discovered very late in the release
5498 that it has problems with process groups that render gdb unusable. Sorry
5499 about that. I encourage people to fix it and post the fixes.
5501 * Preliminary ELF and DWARF support
5503 GDB can read ELF object files on System V Release 4, and can handle
5504 debugging records for C, in DWARF format, in ELF files. This support
5505 is preliminary. If you bring up GDB on another SVR4 system, please
5506 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5511 GDB now uses the latest `readline' library. One user-visible change
5512 is that two tabs will list possible command completions, which previously
5513 required typing M-? (meta-question mark, or ESC ?).
5517 The `stepi' bug that many of you noticed has been squashed.
5518 Many bugs in C++ have been handled. Many more remain to be handled.
5519 See the various ChangeLog files (primarily in gdb and bfd) for details.
5521 * State of the MIPS world (in case you wondered):
5523 GDB can understand the symbol tables emitted by the compilers
5524 supplied by most vendors of MIPS-based machines, including DEC. These
5525 symbol tables are in a format that essentially nobody else uses.
5527 Some versions of gcc come with an assembler post-processor called
5528 mips-tfile. This program is required if you want to do source-level
5529 debugging of gcc-compiled programs. I believe FSF does not ship
5530 mips-tfile with gcc version 1, but it will eventually come with gcc
5533 Debugging of g++ output remains a problem. g++ version 1.xx does not
5534 really support it at all. (If you're lucky, you should be able to get
5535 line numbers and stack traces to work, but no parameters or local
5536 variables.) With some work it should be possible to improve the
5539 When gcc version 2 is released, you will have somewhat better luck.
5540 However, even then you will get confusing results for inheritance and
5543 We will eventually provide full debugging of g++ output on
5544 DECstations. This will probably involve some kind of stabs-in-ecoff
5545 encapulation, but the details have not been worked out yet.
5548 *** Changes in GDB-4.2:
5550 * Improved configuration
5552 Only one copy of `configure' exists now, and it is not self-modifying.
5553 Porting BFD is simpler.
5557 The `step' and `next' commands now only stop at the first instruction
5558 of a source line. This prevents the multiple stops that used to occur
5559 in switch statements, for-loops, etc. `Step' continues to stop if a
5560 function that has debugging information is called within the line.
5564 Lots of small bugs fixed. More remain.
5566 * New host supported (not target)
5568 Intel 386 PC clone running Mach i386-none-mach
5571 *** Changes in GDB-4.1:
5573 * Multiple source language support
5575 GDB now has internal scaffolding to handle several source languages.
5576 It determines the type of each source file from its filename extension,
5577 and will switch expression parsing and number formatting to match the
5578 language of the function in the currently selected stack frame.
5579 You can also specifically set the language to be used, with
5580 `set language c' or `set language modula-2'.
5584 GDB now has preliminary support for the GNU Modula-2 compiler,
5585 currently under development at the State University of New York at
5586 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5587 continue through the fall of 1991 and into 1992.
5589 Other Modula-2 compilers are currently not supported, and attempting to
5590 debug programs compiled with them will likely result in an error as the
5591 symbol table is read. Feel free to work on it, though!
5593 There are hooks in GDB for strict type checking and range checking,
5594 in the `Modula-2 philosophy', but they do not currently work.
5598 GDB can now write to executable and core files (e.g. patch
5599 a variable's value). You must turn this switch on, specify
5600 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5601 by assigning a new value to a variable. Modifications take
5604 * Automatic SunOS shared library reading
5606 When you run your program, GDB automatically determines where its
5607 shared libraries (if any) have been loaded, and reads their symbols.
5608 The `share' command is no longer needed. This also works when
5609 examining core files.
5613 You can specify the number of lines that the `list' command shows.
5616 * New machines supported (host and target)
5618 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5619 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5620 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5622 * New hosts supported (not targets)
5624 IBM RT/PC: romp-ibm-aix or rtpc
5626 * New targets supported (not hosts)
5628 AMD 29000 embedded with COFF a29k-none-coff
5629 AMD 29000 embedded with a.out a29k-none-aout
5630 Ultracomputer remote kernel debug a29k-nyu-kern
5632 * New remote interfaces
5638 *** Changes in GDB-4.0:
5642 Wide output is wrapped at good places to make the output more readable.
5644 Gdb now supports cross-debugging from a host machine of one type to a
5645 target machine of another type. Communication with the target system
5646 is over serial lines. The ``target'' command handles connecting to the
5647 remote system; the ``load'' command will download a program into the
5648 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5649 also supports debugging of realtime processes running under VxWorks,
5650 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5651 stub on the target system.
5653 New CPUs supported include the AMD 29000 and Intel 960.
5655 GDB now reads object files and symbol tables via a ``binary file''
5656 library, which allows a single copy of GDB to debug programs of multiple
5657 object file types such as a.out and coff.
5659 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5660 refcard.dvi and refcard.ps are available to format it).
5663 * Control-Variable user interface simplified
5665 All variables that control the operation of the debugger can be set
5666 by the ``set'' command, and displayed by the ``show'' command.
5668 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5669 ``Show prompt'' produces the response:
5670 Gdb's prompt is new-gdb=>.
5672 What follows are the NEW set commands. The command ``help set'' will
5673 print a complete list of old and new set commands. ``help set FOO''
5674 will give a longer description of the variable FOO. ``show'' will show
5675 all of the variable descriptions and their current settings.
5677 confirm on/off: Enables warning questions for operations that are
5678 hard to recover from, e.g. rerunning the program while
5679 it is already running. Default is ON.
5681 editing on/off: Enables EMACS style command line editing
5682 of input. Previous lines can be recalled with
5683 control-P, the current line can be edited with control-B,
5684 you can search for commands with control-R, etc.
5687 history filename NAME: NAME is where the gdb command history
5688 will be stored. The default is .gdb_history,
5689 or the value of the environment variable
5692 history size N: The size, in commands, of the command history. The
5693 default is 256, or the value of the environment variable
5696 history save on/off: If this value is set to ON, the history file will
5697 be saved after exiting gdb. If set to OFF, the
5698 file will not be saved. The default is OFF.
5700 history expansion on/off: If this value is set to ON, then csh-like
5701 history expansion will be performed on
5702 command line input. The default is OFF.
5704 radix N: Sets the default radix for input and output. It can be set
5705 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5706 in the current radix, so "set radix 10" is always a no-op.
5708 height N: This integer value is the number of lines on a page. Default
5709 is 24, the current `stty rows'' setting, or the ``li#''
5710 setting from the termcap entry matching the environment
5713 width N: This integer value is the number of characters on a line.
5714 Default is 80, the current `stty cols'' setting, or the ``co#''
5715 setting from the termcap entry matching the environment
5718 Note: ``set screensize'' is obsolete. Use ``set height'' and
5719 ``set width'' instead.
5721 print address on/off: Print memory addresses in various command displays,
5722 such as stack traces and structure values. Gdb looks
5723 more ``symbolic'' if you turn this off; it looks more
5724 ``machine level'' with it on. Default is ON.
5726 print array on/off: Prettyprint arrays. New convenient format! Default
5729 print demangle on/off: Print C++ symbols in "source" form if on,
5732 print asm-demangle on/off: Same, for assembler level printouts
5735 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5738 * Support for Epoch Environment.
5740 The epoch environment is a version of Emacs v18 with windowing. One
5741 new command, ``inspect'', is identical to ``print'', except that if you
5742 are running in the epoch environment, the value is printed in its own
5746 * Support for Shared Libraries
5748 GDB can now debug programs and core files that use SunOS shared libraries.
5749 Symbols from a shared library cannot be referenced
5750 before the shared library has been linked with the program (this
5751 happens after you type ``run'' and before the function main() is entered).
5752 At any time after this linking (including when examining core files
5753 from dynamically linked programs), gdb reads the symbols from each
5754 shared library when you type the ``sharedlibrary'' command.
5755 It can be abbreviated ``share''.
5757 sharedlibrary REGEXP: Load shared object library symbols for files
5758 matching a unix regular expression. No argument
5759 indicates to load symbols for all shared libraries.
5761 info sharedlibrary: Status of loaded shared libraries.
5766 A watchpoint stops execution of a program whenever the value of an
5767 expression changes. Checking for this slows down execution
5768 tremendously whenever you are in the scope of the expression, but is
5769 quite useful for catching tough ``bit-spreader'' or pointer misuse
5770 problems. Some machines such as the 386 have hardware for doing this
5771 more quickly, and future versions of gdb will use this hardware.
5773 watch EXP: Set a watchpoint (breakpoint) for an expression.
5775 info watchpoints: Information about your watchpoints.
5777 delete N: Deletes watchpoint number N (same as breakpoints).
5778 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5779 enable N: Re-enables watchpoint number N (same as breakpoints).
5782 * C++ multiple inheritance
5784 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5787 * C++ exception handling
5789 Gdb now supports limited C++ exception handling. Besides the existing
5790 ability to breakpoint on an exception handler, gdb can breakpoint on
5791 the raising of an exception (before the stack is peeled back to the
5794 catch FOO: If there is a FOO exception handler in the dynamic scope,
5795 set a breakpoint to catch exceptions which may be raised there.
5796 Multiple exceptions (``catch foo bar baz'') may be caught.
5798 info catch: Lists all exceptions which may be caught in the
5799 current stack frame.
5802 * Minor command changes
5804 The command ``call func (arg, arg, ...)'' now acts like the print
5805 command, except it does not print or save a value if the function's result
5806 is void. This is similar to dbx usage.
5808 The ``up'' and ``down'' commands now always print the frame they end up
5809 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5810 frames without printing.
5812 * New directory command
5814 'dir' now adds directories to the FRONT of the source search path.
5815 The path starts off empty. Source files that contain debug information
5816 about the directory in which they were compiled can be found even
5817 with an empty path; Sun CC and GCC include this information. If GDB can't
5818 find your source file in the current directory, type "dir .".
5820 * Configuring GDB for compilation
5822 For normal use, type ``./configure host''. See README or gdb.texinfo
5825 GDB now handles cross debugging. If you are remotely debugging between
5826 two different machines, type ``./configure host -target=targ''.
5827 Host is the machine where GDB will run; targ is the machine
5828 where the program that you are debugging will run.