1 What has changed in GDB?
2 (Organized release by release)
6 New events which are triggered when GDB modifies the state of the
9 ** gdb.events.inferior_call_pre: Function call is about to be made.
10 ** gdb.events.inferior_call_post: Function call has just been made.
11 ** gdb.events.memory_changed: A memory location has been altered.
12 ** gdb.events.register_changed: A register has been altered.
14 *** Changes since GDB 7.8
16 * GDB now supports hardware watchpoints on x86 GNU Hurd.
20 ** You can now access frame registers from Python scripts.
21 ** New attribute 'producer' for gdb.Symtab objects.
22 ** gdb.Objfile objects have a new attribute "progspace",
23 which is the gdb.Progspace object of the containing program space.
24 ** gdb.Objfile objects have a new attribute "owner".
25 ** gdb.Objfile objects have a new attribute "build_id",
26 which is the build ID generated when the file was built.
27 ** gdb.Objfile objects have a new method "add_separate_debug_file".
28 ** A new event "gdb.clear_objfiles" has been added, triggered when
29 selecting a new file to debug.
30 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
31 ** New function gdb.lookup_objfile.
33 * New Python-based convenience functions:
35 ** $_caller_is(name [, number_of_frames])
36 ** $_caller_matches(regexp [, number_of_frames])
37 ** $_any_caller_is(name [, number_of_frames])
38 ** $_any_caller_matches(regexp [, number_of_frames])
42 queue-signal signal-name-or-number
43 Queue a signal to be delivered to the thread when it is resumed.
45 add-auto-load-scripts-directory directory
46 Add entries to the list of directories from which to load auto-loaded
49 maint print user-registers
50 List all currently available "user" registers.
52 * On resume, GDB now always passes the signal the program had stopped
53 for to the thread the signal was sent to, even if the user changed
54 threads before resuming. Previously GDB would often (but not
55 always) deliver the signal to the thread that happens to be current
58 * Conversely, the "signal" command now consistently delivers the
59 requested signal to the current thread. GDB now asks for
60 confirmation if the program had stopped for a signal and the user
61 switched threads meanwhile.
63 * "breakpoint always-inserted" modes "off" and "auto" merged.
65 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
66 won't remove breakpoints from the target until all threads stop,
67 even in non-stop mode. The "auto" mode has been removed, and "off"
68 is now the default mode.
72 ** The -list-thread-groups command outputs an exit-code field for
73 inferiors that have exited.
77 Support for these obsolete configurations has been removed.
79 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
80 SGI Irix-5.x mips-*-irix5*
81 SGI Irix-6.x mips-*-irix6*
82 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
83 VAX running Ultrix vax-*-ultrix*
85 *** Changes in GDB 7.8
87 * New command line options
90 This is an alias for the --data-directory option.
92 * GDB supports printing and modifying of variable length automatic arrays
93 as specified in ISO C99.
95 * The ARM simulator now supports instruction level tracing
96 with or without disassembly.
100 GDB now has support for scripting using Guile. Whether this is
101 available is determined at configure time.
102 Guile version 2.0 or greater is required.
103 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
105 * New commands (for set/show, see "New options" below)
109 Invoke CODE by passing it to the Guile interpreter.
113 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
115 info auto-load guile-scripts [regexp]
116 Print the list of automatically loaded Guile scripts.
118 * The source command is now capable of sourcing Guile scripts.
119 This feature is dependent on the debugger being built with Guile support.
123 set print symbol-loading (off|brief|full)
124 show print symbol-loading
125 Control whether to print informational messages when loading symbol
126 information for a file. The default is "full", but when debugging
127 programs with large numbers of shared libraries the amount of output
130 set guile print-stack (none|message|full)
131 show guile print-stack
132 Show a stack trace when an error is encountered in a Guile script.
134 set auto-load guile-scripts (on|off)
135 show auto-load guile-scripts
136 Control auto-loading of Guile script files.
138 maint ada set ignore-descriptive-types (on|off)
139 maint ada show ignore-descriptive-types
140 Control whether the debugger should ignore descriptive types in Ada
141 programs. The default is not to ignore the descriptive types. See
142 the user manual for more details on descriptive types and the intended
143 usage of this option.
145 set auto-connect-native-target
147 Control whether GDB is allowed to automatically connect to the
148 native target for the run, attach, etc. commands when not connected
149 to any target yet. See also "target native" below.
151 set record btrace replay-memory-access (read-only|read-write)
152 show record btrace replay-memory-access
153 Control what memory accesses are allowed during replay.
155 maint set target-async (on|off)
156 maint show target-async
157 This controls whether GDB targets operate in synchronous or
158 asynchronous mode. Normally the default is asynchronous, if it is
159 available; but this can be changed to more easily debug problems
160 occurring only in synchronous mode.
162 set mi-async (on|off)
164 Control whether MI asynchronous mode is preferred. This supersedes
165 "set target-async" of previous GDB versions.
167 * "set target-async" is deprecated as a CLI option and is now an alias
168 for "set mi-async" (only puts MI into async mode).
170 * Background execution commands (e.g., "c&", "s&", etc.) are now
171 possible ``out of the box'' if the target supports them. Previously
172 the user would need to explicitly enable the possibility with the
173 "set target-async on" command.
175 * New features in the GDB remote stub, GDBserver
177 ** New option --debug-format=option1[,option2,...] allows one to add
178 additional text to each output. At present only timestamps
179 are supported: --debug-format=timestamps.
180 Timestamps can also be turned on with the
181 "monitor set debug-format timestamps" command from GDB.
183 * The 'record instruction-history' command now starts counting instructions
184 at one. This also affects the instruction ranges reported by the
185 'record function-call-history' command when given the /i modifier.
187 * The command 'record function-call-history' supports a new modifier '/c' to
188 indent the function names based on their call stack depth.
189 The fields for the '/i' and '/l' modifier have been reordered.
190 The source line range is now prefixed with 'at'.
191 The instruction range is now prefixed with 'inst'.
192 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
193 "record instruction-history" and "list" commands.
195 * The ranges given as arguments to the 'record function-call-history' and
196 'record instruction-history' commands are now inclusive.
198 * The btrace record target now supports the 'record goto' command.
199 For locations inside the execution trace, the back trace is computed
200 based on the information stored in the execution trace.
202 * The btrace record target supports limited reverse execution and replay.
203 The target does not record data and therefore does not allow reading
206 * The "catch syscall" command now works on s390*-linux* targets.
208 * The "compare-sections" command is no longer specific to target
209 remote. It now works with all targets.
211 * All native targets are now consistently called "native".
212 Consequently, the "target child", "target GNU", "target djgpp",
213 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
214 commands have been replaced with "target native". The QNX/NTO port
215 leaves the "procfs" target in place and adds a "native" target for
216 consistency with other ports. The impact on users should be minimal
217 as these commands previously either throwed an error, or were
218 no-ops. The target's name is visible in the output of the following
219 commands: "help target", "info target", "info files", "maint print
222 * The "target native" command now connects to the native target. This
223 can be used to launch native programs even when "set
224 auto-connect-native-target" is set to off.
226 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
228 * Support for Intel(R) AVX-512 registers on GNU/Linux.
229 Support displaying and modifying Intel(R) AVX-512 registers
230 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
234 qXfer:btrace:read's annex
235 The qXfer:btrace:read packet supports a new annex 'delta' to read
236 branch trace incrementally.
240 ** Valid Python operations on gdb.Value objects representing
241 structs/classes invoke the corresponding overloaded operators if
243 ** New `Xmethods' feature in the Python API. Xmethods are
244 additional methods or replacements for existing methods of a C++
245 class. This feature is useful for those cases where a method
246 defined in C++ source code could be inlined or optimized out by
247 the compiler, making it unavailable to GDB.
250 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
252 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
253 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
254 its alias "share", instead.
256 * The commands "set remotebaud" and "show remotebaud" are no longer
257 supported. Use "set serial baud" and "show serial baud" (respectively)
262 ** A new option "-gdb-set mi-async" replaces "-gdb-set
263 target-async". The latter is left as a deprecated alias of the
264 former for backward compatibility. If the target supports it,
265 CLI background execution commands are now always possible by
266 default, independently of whether the frontend stated a
267 preference for asynchronous execution with "-gdb-set mi-async".
268 Previously "-gdb-set target-async off" affected both MI execution
269 commands and CLI execution commands.
271 *** Changes in GDB 7.7
273 * Improved support for process record-replay and reverse debugging on
274 arm*-linux* targets. Support for thumb32 and syscall instruction
275 recording has been added.
277 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
279 * GDB now supports Fission DWP file format version 2.
280 http://gcc.gnu.org/wiki/DebugFission
282 * New convenience function "$_isvoid", to check whether an expression
283 is void. A void expression is an expression where the type of the
284 result is "void". For example, some convenience variables may be
285 "void" when evaluated (e.g., "$_exitcode" before the execution of
286 the program being debugged; or an undefined convenience variable).
287 Another example, when calling a function whose return type is
290 * The "maintenance print objfiles" command now takes an optional regexp.
292 * The "catch syscall" command now works on arm*-linux* targets.
294 * GDB now consistently shows "<not saved>" when printing values of
295 registers the debug info indicates have not been saved in the frame
296 and there's nowhere to retrieve them from
297 (callee-saved/call-clobbered registers):
302 (gdb) info registers rax
305 Before, the former would print "<optimized out>", and the latter
306 "*value not available*".
308 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
313 ** Frame filters and frame decorators have been added.
314 ** Temporary breakpoints are now supported.
315 ** Line tables representation has been added.
316 ** New attribute 'parent_type' for gdb.Field objects.
317 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
318 ** New attribute 'name' for gdb.Type objects.
322 Nios II ELF nios2*-*-elf
323 Nios II GNU/Linux nios2*-*-linux
324 Texas Instruments MSP430 msp430*-*-elf
326 * Removed native configurations
328 Support for these a.out NetBSD and OpenBSD obsolete configurations has
329 been removed. ELF variants of these configurations are kept supported.
331 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
332 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
333 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
334 i[34567]86-*-openbsd3.[0-3]
335 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
336 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
337 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
341 Like "catch throw", but catches a re-thrown exception.
343 Renamed from old "maint check-symtabs".
345 Perform consistency checks on symtabs.
347 Expand symtabs matching an optional regexp.
350 Display the details of GDB configure-time options.
352 maint set|show per-command
353 maint set|show per-command space
354 maint set|show per-command time
355 maint set|show per-command symtab
356 Enable display of per-command gdb resource usage.
358 remove-symbol-file FILENAME
359 remove-symbol-file -a ADDRESS
360 Remove a symbol file added via add-symbol-file. The file to remove
361 can be identified by its filename or by an address that lies within
362 the boundaries of this symbol file in memory.
365 info exceptions REGEXP
366 Display the list of Ada exceptions defined in the program being
367 debugged. If provided, only the exceptions whose names match REGEXP
372 set debug symfile off|on
374 Control display of debugging info regarding reading symbol files and
375 symbol tables within those files
377 set print raw frame-arguments
378 show print raw frame-arguments
379 Set/show whether to print frame arguments in raw mode,
380 disregarding any defined pretty-printers.
382 set remote trace-status-packet
383 show remote trace-status-packet
384 Set/show the use of remote protocol qTStatus packet.
388 Control display of debugging messages related to Nios II targets.
392 Control whether target-assisted range stepping is enabled.
394 set startup-with-shell
395 show startup-with-shell
396 Specifies whether Unix child processes are started via a shell or
401 Use the target memory cache for accesses to the code segment. This
402 improves performance of remote debugging (particularly disassembly).
404 * You can now use a literal value 'unlimited' for options that
405 interpret 0 or -1 as meaning "unlimited". E.g., "set
406 trace-buffer-size unlimited" is now an alias for "set
407 trace-buffer-size -1" and "set height unlimited" is now an alias for
410 * The "set debug symtab-create" debugging option of GDB has been changed to
411 accept a verbosity level. 0 means "off", 1 provides basic debugging
412 output, and values of 2 or greater provides more verbose output.
414 * New command-line options
416 Display the details of GDB configure-time options.
418 * The command 'tsave' can now support new option '-ctf' to save trace
419 buffer in Common Trace Format.
421 * Newly installed $prefix/bin/gcore acts as a shell interface for the
424 * GDB now implements the the C++ 'typeid' operator.
426 * The new convenience variable $_exception holds the exception being
427 thrown or caught at an exception-related catchpoint.
429 * The exception-related catchpoints, like "catch throw", now accept a
430 regular expression which can be used to filter exceptions by type.
432 * The new convenience variable $_exitsignal is automatically set to
433 the terminating signal number when the program being debugged dies
434 due to an uncaught signal.
438 ** All MI commands now accept an optional "--language" option.
439 Support for this feature can be verified by using the "-list-features"
440 command, which should contain "language-option".
442 ** The new command -info-gdb-mi-command allows the user to determine
443 whether a GDB/MI command is supported or not.
445 ** The "^error" result record returned when trying to execute an undefined
446 GDB/MI command now provides a variable named "code" whose content is the
447 "undefined-command" error code. Support for this feature can be verified
448 by using the "-list-features" command, which should contain
449 "undefined-command-error-code".
451 ** The -trace-save MI command can optionally save trace buffer in Common
454 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
456 ** The command -data-list-register-values now accepts an optional
457 "--skip-unavailable" option. When used, only the available registers
460 ** The new command -trace-frame-collected dumps collected variables,
461 computed expressions, tvars, memory and registers in a traceframe.
463 ** The commands -stack-list-locals, -stack-list-arguments and
464 -stack-list-variables now accept an option "--skip-unavailable".
465 When used, only the available locals or arguments are displayed.
467 ** The -exec-run command now accepts an optional "--start" option.
468 When used, the command follows the same semantics as the "start"
469 command, stopping the program's execution at the start of its
470 main subprogram. Support for this feature can be verified using
471 the "-list-features" command, which should contain
472 "exec-run-start-option".
474 ** The new commands -catch-assert and -catch-exceptions insert
475 catchpoints stopping the program when Ada exceptions are raised.
477 ** The new command -info-ada-exceptions provides the equivalent of
478 the new "info exceptions" command.
480 * New system-wide configuration scripts
481 A GDB installation now provides scripts suitable for use as system-wide
482 configuration scripts for the following systems:
486 * GDB now supports target-assigned range stepping with remote targets.
487 This improves the performance of stepping source lines by reducing
488 the number of control packets from/to GDB. See "New remote packets"
491 * GDB now understands the element 'tvar' in the XML traceframe info.
492 It has the id of the collected trace state variables.
494 * On S/390 targets that provide the transactional-execution feature,
495 the program interruption transaction diagnostic block (TDB) is now
496 represented as a number of additional "registers" in GDB.
502 The vCont packet supports a new 'r' action, that tells the remote
503 stub to step through an address range itself, without GDB
504 involvemement at each single-step.
506 qXfer:libraries-svr4:read's annex
507 The previously unused annex of the qXfer:libraries-svr4:read packet
508 is now used to support passing an argument list. The remote stub
509 reports support for this argument list to GDB's qSupported query.
510 The defined arguments are "start" and "prev", used to reduce work
511 necessary for library list updating, resulting in significant
514 * New features in the GDB remote stub, GDBserver
516 ** GDBserver now supports target-assisted range stepping. Currently
517 enabled on x86/x86_64 GNU/Linux targets.
519 ** GDBserver now adds element 'tvar' in the XML in the reply to
520 'qXfer:traceframe-info:read'. It has the id of the collected
521 trace state variables.
523 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
526 * New 'z' formatter for printing and examining memory, this displays the
527 value as hexadecimal zero padded on the left to the size of the type.
529 * GDB can now use Windows x64 unwinding data.
531 * The "set remotebaud" command has been replaced by "set serial baud".
532 Similarly, "show remotebaud" has been replaced by "show serial baud".
533 The "set remotebaud" and "show remotebaud" commands are still available
534 to provide backward compatibility with older versions of GDB.
536 *** Changes in GDB 7.6
538 * Target record has been renamed to record-full.
539 Record/replay is now enabled with the "record full" command.
540 This also affects settings that are associated with full record/replay
541 that have been moved from "set/show record" to "set/show record full":
543 set|show record full insn-number-max
544 set|show record full stop-at-limit
545 set|show record full memory-query
547 * A new record target "record-btrace" has been added. The new target
548 uses hardware support to record the control-flow of a process. It
549 does not support replaying the execution, but it implements the
550 below new commands for investigating the recorded execution log.
551 This new recording method can be enabled using:
555 The "record-btrace" target is only available on Intel Atom processors
556 and requires a Linux kernel 2.6.32 or later.
558 * Two new commands have been added for record/replay to give information
559 about the recorded execution without having to replay the execution.
560 The commands are only supported by "record btrace".
562 record instruction-history prints the execution history at
563 instruction granularity
565 record function-call-history prints the execution history at
568 * New native configurations
570 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
571 FreeBSD/powerpc powerpc*-*-freebsd
572 x86_64/Cygwin x86_64-*-cygwin*
573 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
577 ARM AArch64 aarch64*-*-elf
578 ARM AArch64 GNU/Linux aarch64*-*-linux
579 Lynx 178 PowerPC powerpc-*-lynx*178
580 x86_64/Cygwin x86_64-*-cygwin*
581 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
583 * If the configured location of system.gdbinit file (as given by the
584 --with-system-gdbinit option at configure time) is in the
585 data-directory (as specified by --with-gdb-datadir at configure
586 time) or in one of its subdirectories, then GDB will look for the
587 system-wide init file in the directory specified by the
588 --data-directory command-line option.
590 * New command line options:
592 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
593 other initialization files, unlike -nx which disables all of them.
595 * Removed command line options
597 -epoch This was used by the gdb mode in Epoch, an ancient fork of
600 * The 'ptype' and 'whatis' commands now accept an argument to control
603 * 'info proc' now works on some core files.
607 ** Vectors can be created with gdb.Type.vector.
609 ** Python's atexit.register now works in GDB.
611 ** Types can be pretty-printed via a Python API.
613 ** Python 3 is now supported (in addition to Python 2.4 or later)
615 ** New class gdb.Architecture exposes GDB's internal representation
616 of architecture in the Python API.
618 ** New method Frame.architecture returns the gdb.Architecture object
619 corresponding to the frame's architecture.
621 * New Python-based convenience functions:
623 ** $_memeq(buf1, buf2, length)
624 ** $_streq(str1, str2)
626 ** $_regex(str, regex)
628 * The 'cd' command now defaults to using '~' (the home directory) if not
631 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
632 default for GCC since November 2000.
634 * The command 'forward-search' can now be abbreviated as 'fo'.
636 * The command 'info tracepoints' can now display 'installed on target'
637 or 'not installed on target' for each non-pending location of tracepoint.
639 * New configure options
641 --enable-libmcheck/--disable-libmcheck
642 By default, development versions are built with -lmcheck on hosts
643 that support it, in order to help track memory corruption issues.
644 Release versions, on the other hand, are built without -lmcheck
645 by default. The --enable-libmcheck/--disable-libmcheck configure
646 options allow the user to override that default.
647 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
648 This configure option allows the user to build GDB with
649 libbabeltrace using which GDB can read Common Trace Format data.
651 * New commands (for set/show, see "New options" below)
654 Catch signals. This is similar to "handle", but allows commands and
655 conditions to be attached.
658 List the BFDs known to GDB.
660 python-interactive [command]
662 Start a Python interactive prompt, or evaluate the optional command
663 and print the result of expressions.
666 "py" is a new alias for "python".
668 enable type-printer [name]...
669 disable type-printer [name]...
670 Enable or disable type printers.
674 ** For the Renesas Super-H architecture, the "regs" command has been removed
675 (has been deprecated in GDB 7.5), and "info all-registers" should be used
680 set print type methods (on|off)
681 show print type methods
682 Control whether method declarations are displayed by "ptype".
683 The default is to show them.
685 set print type typedefs (on|off)
686 show print type typedefs
687 Control whether typedef definitions are displayed by "ptype".
688 The default is to show them.
690 set filename-display basename|relative|absolute
691 show filename-display
692 Control the way in which filenames is displayed.
693 The default is "relative", which preserves previous behavior.
695 set trace-buffer-size
696 show trace-buffer-size
697 Request target to change the size of trace buffer.
699 set remote trace-buffer-size-packet auto|on|off
700 show remote trace-buffer-size-packet
701 Control the use of the remote protocol `QTBuffer:size' packet.
705 Control display of debugging messages related to ARM AArch64.
708 set debug coff-pe-read
709 show debug coff-pe-read
710 Control display of debugging messages related to reading of COFF/PE
715 Control display of debugging messages related to Mach-O symbols
718 set debug notification
719 show debug notification
720 Control display of debugging info for async remote notification.
724 ** Command parameter changes are now notified using new async record
725 "=cmd-param-changed".
726 ** Trace frame changes caused by command "tfind" are now notified using
727 new async record "=traceframe-changed".
728 ** The creation, deletion and modification of trace state variables
729 are now notified using new async records "=tsv-created",
730 "=tsv-deleted" and "=tsv-modified".
731 ** The start and stop of process record are now notified using new
732 async record "=record-started" and "=record-stopped".
733 ** Memory changes are now notified using new async record
735 ** The data-disassemble command response will include a "fullname" field
736 containing the absolute file name when source has been requested.
737 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
738 command, to allow pattern filling of memory areas.
739 ** New commands "-catch-load"/"-catch-unload" added for intercepting
740 library load/unload events.
741 ** The response to breakpoint commands and breakpoint async records
742 includes an "installed" field containing a boolean state about each
743 non-pending tracepoint location is whether installed on target or not.
744 ** Output of the "-trace-status" command includes a "trace-file" field
745 containing the name of the trace file being examined. This field is
746 optional, and only present when examining a trace file.
747 ** The "fullname" field is now always present along with the "file" field,
748 even if the file cannot be found by GDB.
750 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
751 You must have the LZMA library available when configuring GDB for this
752 feature to be enabled. For more information, see:
753 http://fedoraproject.org/wiki/Features/MiniDebugInfo
758 Set the size of trace buffer. The remote stub reports support for this
759 packet to gdb's qSupported query.
762 Enable Branch Trace Store (BTS)-based branch tracing for the current
763 thread. The remote stub reports support for this packet to gdb's
767 Disable branch tracing for the current thread. The remote stub reports
768 support for this packet to gdb's qSupported query.
771 Read the traced branches for the current thread. The remote stub
772 reports support for this packet to gdb's qSupported query.
774 *** Changes in GDB 7.5
776 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
777 for more x32 ABI info.
779 * GDB now supports access to MIPS DSP registers on Linux targets.
781 * GDB now supports debugging microMIPS binaries.
783 * The "info os" command on GNU/Linux can now display information on
784 several new classes of objects managed by the operating system:
785 "info os procgroups" lists process groups
786 "info os files" lists file descriptors
787 "info os sockets" lists internet-domain sockets
788 "info os shm" lists shared-memory regions
789 "info os semaphores" lists semaphores
790 "info os msg" lists message queues
791 "info os modules" lists loaded kernel modules
793 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
794 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
795 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
796 options and inspect the probe arguments using the new $_probe_arg family
797 of convenience variables. You can obtain more information about SystemTap
798 in <http://sourceware.org/systemtap/>.
800 * GDB now supports reversible debugging on ARM, it allows you to
801 debug basic ARM and THUMB instructions, and provides
802 record/replay support.
804 * The option "symbol-reloading" has been deleted as it is no longer used.
808 ** GDB commands implemented in Python can now be put in command class
811 ** The "maint set python print-stack on|off" is now deleted.
813 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
814 apply "flag enum"-style pretty-printing to any enum.
816 ** gdb.lookup_symbol can now work when there is no current frame.
818 ** gdb.Symbol now has a 'line' attribute, holding the line number in
819 the source at which the symbol was defined.
821 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
822 method 'value'. The former indicates whether the symbol needs a
823 frame in order to compute its value, and the latter computes the
826 ** A new method 'referenced_value' on gdb.Value objects which can
827 dereference pointer as well as C++ reference values.
829 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
830 which return the global and static blocks (as gdb.Block objects),
831 of the underlying symbol table, respectively.
833 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
834 object associated with a PC value.
836 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
837 of the address range occupied by code for the current source line.
839 * Go language support.
840 GDB now supports debugging programs written in the Go programming
843 * GDBserver now supports stdio connections.
844 E.g. (gdb) target remote | ssh myhost gdbserver - hello
846 * The binary "gdbtui" can no longer be built or installed.
847 Use "gdb -tui" instead.
849 * GDB will now print "flag" enums specially. A flag enum is one where
850 all the enumerator values have no bits in common when pairwise
851 "and"ed. When printing a value whose type is a flag enum, GDB will
852 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
853 (gdb) print (enum E) 3
856 * The filename part of a linespec will now match trailing components
857 of a source file name. For example, "break gcc/expr.c:1000" will
858 now set a breakpoint in build/gcc/expr.c, but not
861 * The "info proc" and "generate-core-file" commands will now also
862 work on remote targets connected to GDBserver on Linux.
864 * The command "info catch" has been removed. It has been disabled
867 * The "catch exception" and "catch assert" commands now accept
868 a condition at the end of the command, much like the "break"
869 command does. For instance:
871 (gdb) catch exception Constraint_Error if Barrier = True
873 Previously, it was possible to add a condition to such catchpoints,
874 but it had to be done as a second step, after the catchpoint had been
875 created, using the "condition" command.
877 * The "info static-tracepoint-marker" command will now also work on
878 native Linux targets with in-process agent.
880 * GDB can now set breakpoints on inlined functions.
882 * The .gdb_index section has been updated to include symbols for
883 inlined functions. GDB will ignore older .gdb_index sections by
884 default, which could cause symbol files to be loaded more slowly
885 until their .gdb_index sections can be recreated. The new command
886 "set use-deprecated-index-sections on" will cause GDB to use any older
887 .gdb_index sections it finds. This will restore performance, but the
888 ability to set breakpoints on inlined functions will be lost in symbol
889 files with older .gdb_index sections.
891 The .gdb_index section has also been updated to record more information
892 about each symbol. This speeds up the "info variables", "info functions"
893 and "info types" commands when used with programs having the .gdb_index
894 section, as well as speeding up debugging with shared libraries using
895 the .gdb_index section.
897 * Ada support for GDB/MI Variable Objects has been added.
899 * GDB can now support 'breakpoint always-inserted mode' in 'record'
904 ** New command -info-os is the MI equivalent of "info os".
906 ** Output logs ("set logging" and related) now include MI output.
910 ** "set use-deprecated-index-sections on|off"
911 "show use-deprecated-index-sections on|off"
912 Controls the use of deprecated .gdb_index sections.
914 ** "catch load" and "catch unload" can be used to stop when a shared
915 library is loaded or unloaded, respectively.
917 ** "enable count" can be used to auto-disable a breakpoint after
920 ** "info vtbl" can be used to show the virtual method tables for
921 C++ and Java objects.
923 ** "explore" and its sub commands "explore value" and "explore type"
924 can be used to recursively explore values and types of
925 expressions. These commands are available only if GDB is
926 configured with '--with-python'.
928 ** "info auto-load" shows status of all kinds of auto-loaded files,
929 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
930 sequences of commands files, "info auto-load python-scripts"
931 shows status of auto-loading Python script files,
932 "info auto-load local-gdbinit" shows status of loading init file
933 (.gdbinit) from current directory and "info auto-load libthread-db" shows
934 status of inferior specific thread debugging shared library loading.
936 ** "info auto-load-scripts", "set auto-load-scripts on|off"
937 and "show auto-load-scripts" commands have been deprecated, use their
938 "info auto-load python-scripts", "set auto-load python-scripts on|off"
939 and "show auto-load python-scripts" counterparts instead.
941 ** "dprintf location,format,args..." creates a dynamic printf, which
942 is basically a breakpoint that does a printf and immediately
943 resumes your program's execution, so it is like a printf that you
944 can insert dynamically at runtime instead of at compiletime.
946 ** "set print symbol"
948 Controls whether GDB attempts to display the symbol, if any,
949 corresponding to addresses it prints. This defaults to "on", but
950 you can set it to "off" to restore GDB's previous behavior.
952 * Deprecated commands
954 ** For the Renesas Super-H architecture, the "regs" command has been
955 deprecated, and "info all-registers" should be used instead.
959 Renesas RL78 rl78-*-elf
960 HP OpenVMS ia64 ia64-hp-openvms*
962 * GDBserver supports evaluation of breakpoint conditions. When
963 support is advertised by GDBserver, GDB may be told to send the
964 breakpoint conditions in bytecode form to GDBserver. GDBserver
965 will only report the breakpoint trigger to GDB when its condition
971 show mips compression
972 Select the compressed ISA encoding used in functions that have no symbol
973 information available. The encoding can be set to either of:
976 and is updated automatically from ELF file flags if available.
978 set breakpoint condition-evaluation
979 show breakpoint condition-evaluation
980 Control whether breakpoint conditions are evaluated by GDB ("host") or by
981 GDBserver ("target"). Default option "auto" chooses the most efficient
983 This option can improve debugger efficiency depending on the speed of the
987 Disable auto-loading globally.
990 Show auto-loading setting of all kinds of auto-loaded files.
992 set auto-load gdb-scripts on|off
993 show auto-load gdb-scripts
994 Control auto-loading of GDB canned sequences of commands files.
996 set auto-load python-scripts on|off
997 show auto-load python-scripts
998 Control auto-loading of Python script files.
1000 set auto-load local-gdbinit on|off
1001 show auto-load local-gdbinit
1002 Control loading of init file (.gdbinit) from current directory.
1004 set auto-load libthread-db on|off
1005 show auto-load libthread-db
1006 Control auto-loading of inferior specific thread debugging shared library.
1008 set auto-load scripts-directory <dir1>[:<dir2>...]
1009 show auto-load scripts-directory
1010 Set a list of directories from which to load auto-loaded scripts.
1011 Automatically loaded Python scripts and GDB scripts are located in one
1012 of the directories listed by this option.
1013 The delimiter (':' above) may differ according to the host platform.
1015 set auto-load safe-path <dir1>[:<dir2>...]
1016 show auto-load safe-path
1017 Set a list of directories from which it is safe to auto-load files.
1018 The delimiter (':' above) may differ according to the host platform.
1020 set debug auto-load on|off
1021 show debug auto-load
1022 Control display of debugging info for auto-loading the files above.
1024 set dprintf-style gdb|call|agent
1026 Control the way in which a dynamic printf is performed; "gdb"
1027 requests a GDB printf command, while "call" causes dprintf to call a
1028 function in the inferior. "agent" requests that the target agent
1029 (such as GDBserver) do the printing.
1031 set dprintf-function <expr>
1032 show dprintf-function
1033 set dprintf-channel <expr>
1034 show dprintf-channel
1035 Set the function and optional first argument to the call when using
1036 the "call" style of dynamic printf.
1038 set disconnected-dprintf on|off
1039 show disconnected-dprintf
1040 Control whether agent-style dynamic printfs continue to be in effect
1041 after GDB disconnects.
1043 * New configure options
1045 --with-auto-load-dir
1046 Configure default value for the 'set auto-load scripts-directory'
1047 setting above. It defaults to '$debugdir:$datadir/auto-load',
1048 $debugdir representing global debugging info directories (available
1049 via 'show debug-file-directory') and $datadir representing GDB's data
1050 directory (available via 'show data-directory').
1052 --with-auto-load-safe-path
1053 Configure default value for the 'set auto-load safe-path' setting
1054 above. It defaults to the --with-auto-load-dir setting.
1056 --without-auto-load-safe-path
1057 Set 'set auto-load safe-path' to '/', effectively disabling this
1060 * New remote packets
1062 z0/z1 conditional breakpoints extension
1064 The z0/z1 breakpoint insertion packets have been extended to carry
1065 a list of conditional expressions over to the remote stub depending on the
1066 condition evaluation mode. The use of this extension can be controlled
1067 via the "set remote conditional-breakpoints-packet" command.
1071 Specify the signals which the remote stub may pass to the debugged
1072 program without GDB involvement.
1074 * New command line options
1076 --init-command=FILE, -ix Like --command, -x but execute it
1077 before loading inferior.
1078 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1079 execute it before loading inferior.
1081 *** Changes in GDB 7.4
1083 * GDB now handles ambiguous linespecs more consistently; the existing
1084 FILE:LINE support has been expanded to other types of linespecs. A
1085 breakpoint will now be set on all matching locations in all
1086 inferiors, and locations will be added or removed according to
1089 * GDB now allows you to skip uninteresting functions and files when
1090 stepping with the "skip function" and "skip file" commands.
1092 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1093 and "show remote hardware-watchpoint-length-limit". These allows to
1094 set or show the maximum length limit (in bytes) of a remote
1095 target hardware watchpoint.
1097 This allows e.g. to use "unlimited" hardware watchpoints with the
1098 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1099 watchpoints are slower than real hardware watchpoints but are
1100 significantly faster than gdb software watchpoints.
1104 ** The register_pretty_printer function in module gdb.printing now takes
1105 an optional `replace' argument. If True, the new printer replaces any
1108 ** The "maint set python print-stack on|off" command has been
1109 deprecated and will be deleted in GDB 7.5.
1110 A new command: "set python print-stack none|full|message" has
1111 replaced it. Additionally, the default for "print-stack" is
1112 now "message", which just prints the error message without
1115 ** A prompt substitution hook (prompt_hook) is now available to the
1118 ** A new Python module, gdb.prompt has been added to the GDB Python
1119 modules library. This module provides functionality for
1120 escape sequences in prompts (used by set/show
1121 extended-prompt). These escape sequences are replaced by their
1122 corresponding value.
1124 ** Python commands and convenience-functions located in
1125 'data-directory'/python/gdb/command and
1126 'data-directory'/python/gdb/function are now automatically loaded
1129 ** Blocks now provide four new attributes. global_block and
1130 static_block will return the global and static blocks
1131 respectively. is_static and is_global are boolean attributes
1132 that indicate if the block is one of those two types.
1134 ** Symbols now provide the "type" attribute, the type of the symbol.
1136 ** The "gdb.breakpoint" function has been deprecated in favor of
1139 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1140 of a function. This class is based on the "finish" command
1141 available in the CLI.
1143 ** Type objects for struct and union types now allow access to
1144 the fields using standard Python dictionary (mapping) methods.
1145 For example, "some_type['myfield']" now works, as does
1146 "some_type.items()".
1148 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1151 ** A new function, "deep_items" has been added to the gdb.types
1152 module in the GDB Python modules library. This function returns
1153 an iterator over the fields of a struct or union type. Unlike
1154 the standard Python "iteritems" method, it will recursively traverse
1155 any anonymous fields.
1159 ** "*stopped" events can report several new "reason"s, such as
1162 ** Breakpoint changes are now notified using new async records, like
1163 "=breakpoint-modified".
1165 ** New command -ada-task-info.
1167 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1168 $sdir specifies the default system locations of shared libraries.
1169 $pdir specifies the directory where the libpthread used by the application
1172 GDB no longer looks in $sdir and $pdir after it has searched the directories
1173 mentioned in libthread-db-search-path. If you want to search those
1174 directories, they must be specified in libthread-db-search-path.
1175 The default value of libthread-db-search-path on GNU/Linux and Solaris
1176 systems is now "$sdir:$pdir".
1178 $pdir is not supported by gdbserver, it is currently ignored.
1179 $sdir is supported by gdbserver.
1181 * New configure option --with-iconv-bin.
1182 When using the internationalization support like the one in the GNU C
1183 library, GDB will invoke the "iconv" program to get a list of supported
1184 character sets. If this program lives in a non-standard location, one can
1185 use this option to specify where to find it.
1187 * When natively debugging programs on PowerPC BookE processors running
1188 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1189 watchpoints, which specify a mask in addition to an address to watch.
1190 The mask specifies that some bits of an address (the bits which are
1191 reset in the mask) should be ignored when matching the address accessed
1192 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1193 section in the user manual for more details.
1195 * The new option --once causes GDBserver to stop listening for connections once
1196 the first connection is made. The listening port used by GDBserver will
1197 become available after that.
1199 * New commands "info macros" and "alias" have been added.
1201 * New function parameters suffix @entry specifies value of function parameter
1202 at the time the function got called. Entry values are available only since
1208 "!" is now an alias of the "shell" command.
1209 Note that no space is needed between "!" and SHELL COMMAND.
1213 watch EXPRESSION mask MASK_VALUE
1214 The watch command now supports the mask argument which allows creation
1215 of masked watchpoints, if the current architecture supports this feature.
1217 info auto-load-scripts [REGEXP]
1218 This command was formerly named "maintenance print section-scripts".
1219 It is now generally useful and is no longer a maintenance-only command.
1221 info macro [-all] [--] MACRO
1222 The info macro command has new options `-all' and `--'. The first for
1223 printing all definitions of a macro. The second for explicitly specifying
1224 the end of arguments and the beginning of the macro name in case the macro
1225 name starts with a hyphen.
1227 collect[/s] EXPRESSIONS
1228 The tracepoint collect command now takes an optional modifier "/s"
1229 that directs it to dereference pointer-to-character types and
1230 collect the bytes of memory up to a zero byte. The behavior is
1231 similar to what you see when you use the regular print command on a
1232 string. An optional integer following the "/s" sets a bound on the
1233 number of bytes that will be collected.
1236 The trace start command now interprets any supplied arguments as a
1237 note to be recorded with the trace run, with an effect similar to
1238 setting the variable trace-notes.
1241 The trace stop command now interprets any arguments as a note to be
1242 mentioned along with the tstatus report that the trace was stopped
1243 with a command. The effect is similar to setting the variable
1246 * Tracepoints can now be enabled and disabled at any time after a trace
1247 experiment has been started using the standard "enable" and "disable"
1248 commands. It is now possible to start a trace experiment with no enabled
1249 tracepoints; GDB will display a warning, but will allow the experiment to
1250 begin, assuming that tracepoints will be enabled as needed while the trace
1253 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1254 locations with 4-byte instructions, when they were previously
1255 limited to locations with instructions of 5 bytes or longer.
1259 set debug dwarf2-read
1260 show debug dwarf2-read
1261 Turns on or off display of debugging messages related to reading
1262 DWARF debug info. The default is off.
1264 set debug symtab-create
1265 show debug symtab-create
1266 Turns on or off display of debugging messages related to symbol table
1267 creation. The default is off.
1270 show extended-prompt
1271 Set the GDB prompt, and allow escape sequences to be inserted to
1272 display miscellaneous information (see 'help set extended-prompt'
1273 for the list of sequences). This prompt (and any information
1274 accessed through the escape sequences) is updated every time the
1275 prompt is displayed.
1277 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1278 show print entry-values
1279 Set printing of frame argument values at function entry. In some cases
1280 GDB can determine the value of function argument which was passed by the
1281 function caller, even if the value was modified inside the called function.
1283 set debug entry-values
1284 show debug entry-values
1285 Control display of debugging info for determining frame argument values at
1286 function entry and virtual tail call frames.
1288 set basenames-may-differ
1289 show basenames-may-differ
1290 Set whether a source file may have multiple base names.
1291 (A "base name" is the name of a file with the directory part removed.
1292 Example: The base name of "/home/user/hello.c" is "hello.c".)
1293 If set, GDB will canonicalize file names (e.g., expand symlinks)
1294 before comparing them. Canonicalization is an expensive operation,
1295 but it allows the same file be known by more than one base name.
1296 If not set (the default), all source files are assumed to have just
1297 one base name, and gdb will do file name comparisons more efficiently.
1303 Set a user name and notes for the current and any future trace runs.
1304 This is useful for long-running and/or disconnected traces, to
1305 inform others (or yourself) as to who is running the trace, supply
1306 contact information, or otherwise explain what is going on.
1308 set trace-stop-notes
1309 show trace-stop-notes
1310 Set a note attached to the trace run, that is displayed when the
1311 trace has been stopped by a tstop command. This is useful for
1312 instance as an explanation, if you are stopping a trace run that was
1313 started by someone else.
1315 * New remote packets
1319 Dynamically enable a tracepoint in a started trace experiment.
1323 Dynamically disable a tracepoint in a started trace experiment.
1327 Set the user and notes of the trace run.
1331 Query the current status of a tracepoint.
1335 Query the minimum length of instruction at which a fast tracepoint may
1338 * Dcache size (number of lines) and line-size are now runtime-configurable
1339 via "set dcache line" and "set dcache line-size" commands.
1343 Texas Instruments TMS320C6x tic6x-*-*
1347 Renesas RL78 rl78-*-elf
1349 *** Changes in GDB 7.3.1
1351 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1353 *** Changes in GDB 7.3
1355 * GDB has a new command: "thread find [REGEXP]".
1356 It finds the thread id whose name, target id, or thread extra info
1357 matches the given regular expression.
1359 * The "catch syscall" command now works on mips*-linux* targets.
1361 * The -data-disassemble MI command now supports modes 2 and 3 for
1362 dumping the instruction opcodes.
1364 * New command line options
1366 -data-directory DIR Specify DIR as the "data-directory".
1367 This is mostly for testing purposes.
1369 * The "maint set python auto-load on|off" command has been renamed to
1370 "set auto-load-scripts on|off".
1372 * GDB has a new command: "set directories".
1373 It is like the "dir" command except that it replaces the
1374 source path list instead of augmenting it.
1376 * GDB now understands thread names.
1378 On GNU/Linux, "info threads" will display the thread name as set by
1379 prctl or pthread_setname_np.
1381 There is also a new command, "thread name", which can be used to
1382 assign a name internally for GDB to display.
1385 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1386 has been integrated into GDB.
1390 ** The function gdb.Write now accepts an optional keyword 'stream'.
1391 This keyword, when provided, will direct the output to either
1392 stdout, stderr, or GDB's logging output.
1394 ** Parameters can now be be sub-classed in Python, and in particular
1395 you may implement the get_set_doc and get_show_doc functions.
1396 This improves how Parameter set/show documentation is processed
1397 and allows for more dynamic content.
1399 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1400 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1401 have an is_valid method.
1403 ** Breakpoints can now be sub-classed in Python, and in particular
1404 you may implement a 'stop' function that is executed each time
1405 the inferior reaches that breakpoint.
1407 ** New function gdb.lookup_global_symbol looks up a global symbol.
1409 ** GDB values in Python are now callable if the value represents a
1410 function. For example, if 'some_value' represents a function that
1411 takes two integer parameters and returns a value, you can call
1412 that function like so:
1414 result = some_value (10,20)
1416 ** Module gdb.types has been added.
1417 It contains a collection of utilities for working with gdb.Types objects:
1418 get_basic_type, has_field, make_enum_dict.
1420 ** Module gdb.printing has been added.
1421 It contains utilities for writing and registering pretty-printers.
1422 New classes: PrettyPrinter, SubPrettyPrinter,
1423 RegexpCollectionPrettyPrinter.
1424 New function: register_pretty_printer.
1426 ** New commands "info pretty-printers", "enable pretty-printer" and
1427 "disable pretty-printer" have been added.
1429 ** gdb.parameter("directories") is now available.
1431 ** New function gdb.newest_frame returns the newest frame in the
1434 ** The gdb.InferiorThread class has a new "name" attribute. This
1435 holds the thread's name.
1437 ** Python Support for Inferior events.
1438 Python scripts can add observers to be notified of events
1439 occurring in the process being debugged.
1440 The following events are currently supported:
1441 - gdb.events.cont Continue event.
1442 - gdb.events.exited Inferior exited event.
1443 - gdb.events.stop Signal received, and Breakpoint hit events.
1447 ** GDB now puts template parameters in scope when debugging in an
1448 instantiation. For example, if you have:
1450 template<int X> int func (void) { return X; }
1452 then if you step into func<5>, "print X" will show "5". This
1453 feature requires proper debuginfo support from the compiler; it
1454 was added to GCC 4.5.
1456 ** The motion commands "next", "finish", "until", and "advance" now
1457 work better when exceptions are thrown. In particular, GDB will
1458 no longer lose control of the inferior; instead, the GDB will
1459 stop the inferior at the point at which the exception is caught.
1460 This functionality requires a change in the exception handling
1461 code that was introduced in GCC 4.5.
1463 * GDB now follows GCC's rules on accessing volatile objects when
1464 reading or writing target state during expression evaluation.
1465 One notable difference to prior behavior is that "print x = 0"
1466 no longer generates a read of x; the value of the assignment is
1467 now always taken directly from the value being assigned.
1469 * GDB now has some support for using labels in the program's source in
1470 linespecs. For instance, you can use "advance label" to continue
1471 execution to a label.
1473 * GDB now has support for reading and writing a new .gdb_index
1474 section. This section holds a fast index of DWARF debugging
1475 information and can be used to greatly speed up GDB startup and
1476 operation. See the documentation for `save gdb-index' for details.
1478 * The "watch" command now accepts an optional "-location" argument.
1479 When used, this causes GDB to watch the memory referred to by the
1480 expression. Such a watchpoint is never deleted due to it going out
1483 * GDB now supports thread debugging of core dumps on GNU/Linux.
1485 GDB now activates thread debugging using the libthread_db library
1486 when debugging GNU/Linux core dumps, similarly to when debugging
1487 live processes. As a result, when debugging a core dump file, GDB
1488 is now able to display pthread_t ids of threads. For example, "info
1489 threads" shows the same output as when debugging the process when it
1490 was live. In earlier releases, you'd see something like this:
1493 * 1 LWP 6780 main () at main.c:10
1495 While now you see this:
1498 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1500 It is also now possible to inspect TLS variables when debugging core
1503 When debugging a core dump generated on a machine other than the one
1504 used to run GDB, you may need to point GDB at the correct
1505 libthread_db library with the "set libthread-db-search-path"
1506 command. See the user manual for more details on this command.
1508 * When natively debugging programs on PowerPC BookE processors running
1509 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1510 which stop execution of the inferior whenever it executes an instruction
1511 at any address within the specified range. See the "PowerPC Embedded"
1512 section in the user manual for more details.
1514 * New features in the GDB remote stub, GDBserver
1516 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1517 and i686 LynxOS (version 5.x).
1519 ** GDBserver is now supported on Blackfin Linux.
1521 * New native configurations
1523 ia64 HP-UX ia64-*-hpux*
1527 Analog Devices, Inc. Blackfin Processor bfin-*
1529 * Ada task switching is now supported on sparc-elf targets when
1530 debugging a program using the Ravenscar Profile. For more information,
1531 see the "Tasking Support when using the Ravenscar Profile" section
1532 in the GDB user manual.
1534 * Guile support was removed.
1536 * New features in the GNU simulator
1538 ** The --map-info flag lists all known core mappings.
1540 ** CFI flashes may be simulated via the "cfi" device.
1542 *** Changes in GDB 7.2
1544 * Shared library support for remote targets by default
1546 When GDB is configured for a generic, non-OS specific target, like
1547 for example, --target=arm-eabi or one of the many *-*-elf targets,
1548 GDB now queries remote stubs for loaded shared libraries using the
1549 `qXfer:libraries:read' packet. Previously, shared library support
1550 was always disabled for such configurations.
1554 ** Argument Dependent Lookup (ADL)
1556 In C++ ADL lookup directs function search to the namespaces of its
1557 arguments even if the namespace has not been imported.
1567 Here the compiler will search for `foo' in the namespace of 'b'
1568 and find A::foo. GDB now supports this. This construct is commonly
1569 used in the Standard Template Library for operators.
1571 ** Improved User Defined Operator Support
1573 In addition to member operators, GDB now supports lookup of operators
1574 defined in a namespace and imported with a `using' directive, operators
1575 defined in the global scope, operators imported implicitly from an
1576 anonymous namespace, and the ADL operators mentioned in the previous
1578 GDB now also supports proper overload resolution for all the previously
1579 mentioned flavors of operators.
1581 ** static const class members
1583 Printing of static const class members that are initialized in the
1584 class definition has been fixed.
1586 * Windows Thread Information Block access.
1588 On Windows targets, GDB now supports displaying the Windows Thread
1589 Information Block (TIB) structure. This structure is visible either
1590 by using the new command `info w32 thread-information-block' or, by
1591 dereferencing the new convenience variable named `$_tlb', a
1592 thread-specific pointer to the TIB. This feature is also supported
1593 when remote debugging using GDBserver.
1595 * Static tracepoints
1597 Static tracepoints are calls in the user program into a tracing
1598 library. One such library is a port of the LTTng kernel tracer to
1599 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1600 When debugging with GDBserver, GDB now supports combining the GDB
1601 tracepoint machinery with such libraries. For example: the user can
1602 use GDB to probe a static tracepoint marker (a call from the user
1603 program into the tracing library) with the new "strace" command (see
1604 "New commands" below). This creates a "static tracepoint" in the
1605 breakpoint list, that can be manipulated with the same feature set
1606 as fast and regular tracepoints. E.g., collect registers, local and
1607 global variables, collect trace state variables, and define
1608 tracepoint conditions. In addition, the user can collect extra
1609 static tracepoint marker specific data, by collecting the new
1610 $_sdata internal variable. When analyzing the trace buffer, you can
1611 inspect $_sdata like any other variable available to GDB. For more
1612 information, see the "Tracepoints" chapter in GDB user manual. New
1613 remote packets have been defined to support static tracepoints, see
1614 the "New remote packets" section below.
1616 * Better reconstruction of tracepoints after disconnected tracing
1618 GDB will attempt to download the original source form of tracepoint
1619 definitions when starting a trace run, and then will upload these
1620 upon reconnection to the target, resulting in a more accurate
1621 reconstruction of the tracepoints that are in use on the target.
1625 You can now exercise direct control over the ways that GDB can
1626 affect your program. For instance, you can disallow the setting of
1627 breakpoints, so that the program can run continuously (assuming
1628 non-stop mode). In addition, the "observer" variable is available
1629 to switch all of the different controls; in observer mode, GDB
1630 cannot affect the target's behavior at all, which is useful for
1631 tasks like diagnosing live systems in the field.
1633 * The new convenience variable $_thread holds the number of the
1636 * New remote packets
1640 Return the address of the Windows Thread Information Block of a given thread.
1644 In response to several of the tracepoint packets, the target may now
1645 also respond with a number of intermediate `qRelocInsn' request
1646 packets before the final result packet, to have GDB handle
1647 relocating an instruction to execute at a different address. This
1648 is particularly useful for stubs that support fast tracepoints. GDB
1649 reports support for this feature in the qSupported packet.
1653 List static tracepoint markers in the target program.
1657 List static tracepoint markers at a given address in the target
1660 qXfer:statictrace:read
1662 Read the static trace data collected (by a `collect $_sdata'
1663 tracepoint action). The remote stub reports support for this packet
1664 to gdb's qSupported query.
1668 Send the current settings of GDB's permission flags.
1672 Send part of the source (textual) form of a tracepoint definition,
1673 which includes location, conditional, and action list.
1675 * The source command now accepts a -s option to force searching for the
1676 script in the source search path even if the script name specifies
1679 * New features in the GDB remote stub, GDBserver
1681 - GDBserver now support tracepoints (including fast tracepoints, and
1682 static tracepoints). The feature is currently supported by the
1683 i386-linux and amd64-linux builds. See the "Tracepoints support
1684 in gdbserver" section in the manual for more information.
1686 GDBserver JIT compiles the tracepoint's conditional agent
1687 expression bytecode into native code whenever possible for low
1688 overhead dynamic tracepoints conditionals. For such tracepoints,
1689 an expression that examines program state is evaluated when the
1690 tracepoint is reached, in order to determine whether to capture
1691 trace data. If the condition is simple and false, processing the
1692 tracepoint finishes very quickly and no data is gathered.
1694 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1695 for static tracepoints support.
1697 - GDBserver now supports x86_64 Windows 64-bit debugging.
1699 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1700 it understands register description.
1702 * The --batch flag now disables pagination and queries.
1704 * X86 general purpose registers
1706 GDB now supports reading/writing byte, word and double-word x86
1707 general purpose registers directly. This means you can use, say,
1708 $ah or $ax to refer, respectively, to the byte register AH and
1709 16-bit word register AX that are actually portions of the 32-bit
1710 register EAX or 64-bit register RAX.
1712 * The `commands' command now accepts a range of breakpoints to modify.
1713 A plain `commands' following a command that creates multiple
1714 breakpoints affects all the breakpoints set by that command. This
1715 applies to breakpoints set by `rbreak', and also applies when a
1716 single `break' command creates multiple breakpoints (e.g.,
1717 breakpoints on overloaded c++ functions).
1719 * The `rbreak' command now accepts a filename specification as part of
1720 its argument, limiting the functions selected by the regex to those
1721 in the specified file.
1723 * Support for remote debugging Windows and SymbianOS shared libraries
1724 from Unix hosts has been improved. Non Windows GDB builds now can
1725 understand target reported file names that follow MS-DOS based file
1726 system semantics, such as file names that include drive letters and
1727 use the backslash character as directory separator. This makes it
1728 possible to transparently use the "set sysroot" and "set
1729 solib-search-path" on Unix hosts to point as host copies of the
1730 target's shared libraries. See the new command "set
1731 target-file-system-kind" described below, and the "Commands to
1732 specify files" section in the user manual for more information.
1736 eval template, expressions...
1737 Convert the values of one or more expressions under the control
1738 of the string template to a command line, and call it.
1740 set target-file-system-kind unix|dos-based|auto
1741 show target-file-system-kind
1742 Set or show the assumed file system kind for target reported file
1745 save breakpoints <filename>
1746 Save all current breakpoint definitions to a file suitable for use
1747 in a later debugging session. To read the saved breakpoint
1748 definitions, use the `source' command.
1750 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1753 info static-tracepoint-markers
1754 Display information about static tracepoint markers in the target.
1756 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1757 Define a static tracepoint by probing a marker at the given
1758 function, line, address, or marker ID.
1762 Enable and disable observer mode.
1764 set may-write-registers on|off
1765 set may-write-memory on|off
1766 set may-insert-breakpoints on|off
1767 set may-insert-tracepoints on|off
1768 set may-insert-fast-tracepoints on|off
1769 set may-interrupt on|off
1770 Set individual permissions for GDB effects on the target. Note that
1771 some of these settings can have undesirable or surprising
1772 consequences, particularly when changed in the middle of a session.
1773 For instance, disabling the writing of memory can prevent
1774 breakpoints from being inserted, cause single-stepping to fail, or
1775 even crash your program, if you disable after breakpoints have been
1776 inserted. However, GDB should not crash.
1778 set record memory-query on|off
1779 show record memory-query
1780 Control whether to stop the inferior if memory changes caused
1781 by an instruction cannot be recorded.
1786 The disassemble command now supports "start,+length" form of two arguments.
1790 ** GDB now provides a new directory location, called the python directory,
1791 where Python scripts written for GDB can be installed. The location
1792 of that directory is <data-directory>/python, where <data-directory>
1793 is the GDB data directory. For more details, see section `Scripting
1794 GDB using Python' in the manual.
1796 ** The GDB Python API now has access to breakpoints, symbols, symbol
1797 tables, program spaces, inferiors, threads and frame's code blocks.
1798 Additionally, GDB Parameters can now be created from the API, and
1799 manipulated via set/show in the CLI.
1801 ** New functions gdb.target_charset, gdb.target_wide_charset,
1802 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1804 ** New exception gdb.GdbError.
1806 ** Pretty-printers are now also looked up in the current program space.
1808 ** Pretty-printers can now be individually enabled and disabled.
1810 ** GDB now looks for names of Python scripts to auto-load in a
1811 special section named `.debug_gdb_scripts', in addition to looking
1812 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1814 * Tracepoint actions were unified with breakpoint commands. In particular,
1815 there are no longer differences in "info break" output for breakpoints and
1816 tracepoints and the "commands" command can be used for both tracepoints and
1817 regular breakpoints.
1821 ARM Symbian arm*-*-symbianelf*
1823 * D language support.
1824 GDB now supports debugging programs written in the D programming
1827 * GDB now supports the extended ptrace interface for PowerPC which is
1828 available since Linux kernel version 2.6.34. This automatically enables
1829 any hardware breakpoints and additional hardware watchpoints available in
1830 the processor. The old ptrace interface exposes just one hardware
1831 watchpoint and no hardware breakpoints.
1833 * GDB is now able to use the Data Value Compare (DVC) register available on
1834 embedded PowerPC processors to implement in hardware simple watchpoint
1835 conditions of the form:
1837 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1839 This works in native GDB running on Linux kernels with the extended ptrace
1840 interface mentioned above.
1842 *** Changes in GDB 7.1
1846 ** Namespace Support
1848 GDB now supports importing of namespaces in C++. This enables the
1849 user to inspect variables from imported namespaces. Support for
1850 namepace aliasing has also been added. So, if a namespace is
1851 aliased in the current scope (e.g. namepace C=A; ) the user can
1852 print variables using the alias (e.g. (gdb) print C::x).
1856 All known bugs relating to the printing of virtual base class were
1857 fixed. It is now possible to call overloaded static methods using a
1862 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1863 and reinterpret_cast<> are now handled by the C++ expression parser.
1867 Xilinx MicroBlaze microblaze-*-*
1872 Xilinx MicroBlaze microblaze
1875 * Multi-program debugging.
1877 GDB now has support for multi-program (a.k.a. multi-executable or
1878 multi-exec) debugging. This allows for debugging multiple inferiors
1879 simultaneously each running a different program under the same GDB
1880 session. See "Debugging Multiple Inferiors and Programs" in the
1881 manual for more information. This implied some user visible changes
1882 in the multi-inferior support. For example, "info inferiors" now
1883 lists inferiors that are not running yet or that have exited
1884 already. See also "New commands" and "New options" below.
1886 * New tracing features
1888 GDB's tracepoint facility now includes several new features:
1890 ** Trace state variables
1892 GDB tracepoints now include support for trace state variables, which
1893 are variables managed by the target agent during a tracing
1894 experiment. They are useful for tracepoints that trigger each
1895 other, so for instance one tracepoint can count hits in a variable,
1896 and then a second tracepoint has a condition that is true when the
1897 count reaches a particular value. Trace state variables share the
1898 $-syntax of GDB convenience variables, and can appear in both
1899 tracepoint actions and condition expressions. Use the "tvariable"
1900 command to create, and "info tvariables" to view; see "Trace State
1901 Variables" in the manual for more detail.
1905 GDB now includes an option for defining fast tracepoints, which
1906 targets may implement more efficiently, such as by installing a jump
1907 into the target agent rather than a trap instruction. The resulting
1908 speedup can be by two orders of magnitude or more, although the
1909 tradeoff is that some program locations on some target architectures
1910 might not allow fast tracepoint installation, for instance if the
1911 instruction to be replaced is shorter than the jump. To request a
1912 fast tracepoint, use the "ftrace" command, with syntax identical to
1913 the regular trace command.
1915 ** Disconnected tracing
1917 It is now possible to detach GDB from the target while it is running
1918 a trace experiment, then reconnect later to see how the experiment
1919 is going. In addition, a new variable disconnected-tracing lets you
1920 tell the target agent whether to continue running a trace if the
1921 connection is lost unexpectedly.
1925 GDB now has the ability to save the trace buffer into a file, and
1926 then use that file as a target, similarly to you can do with
1927 corefiles. You can select trace frames, print data that was
1928 collected in them, and use tstatus to display the state of the
1929 tracing run at the moment that it was saved. To create a trace
1930 file, use "tsave <filename>", and to use it, do "target tfile
1933 ** Circular trace buffer
1935 You can ask the target agent to handle the trace buffer as a
1936 circular buffer, discarding the oldest trace frames to make room for
1937 newer ones, by setting circular-trace-buffer to on. This feature may
1938 not be available for all target agents.
1943 The disassemble command, when invoked with two arguments, now requires
1944 the arguments to be comma-separated.
1947 The info variables command now displays variable definitions. Files
1948 which only declare a variable are not shown.
1951 The source command is now capable of sourcing Python scripts.
1952 This feature is dependent on the debugger being build with Python
1955 Related to this enhancement is also the introduction of a new command
1956 "set script-extension" (see below).
1958 * New commands (for set/show, see "New options" below)
1960 record save [<FILENAME>]
1961 Save a file (in core file format) containing the process record
1962 execution log for replay debugging at a later time.
1964 record restore <FILENAME>
1965 Restore the process record execution log that was saved at an
1966 earlier time, for replay debugging.
1968 add-inferior [-copies <N>] [-exec <FILENAME>]
1971 clone-inferior [-copies <N>] [ID]
1972 Make a new inferior ready to execute the same program another
1973 inferior has loaded.
1978 maint info program-spaces
1979 List the program spaces loaded into GDB.
1981 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1982 show remote interrupt-sequence
1983 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1984 as the sequence to the remote target in order to interrupt the execution.
1985 Ctrl-C is a default. Some system prefers BREAK which is high level of
1986 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1987 Magic SysRq g. It is BREAK signal and character 'g'.
1989 set remote interrupt-on-connect [on | off]
1990 show remote interrupt-on-connect
1991 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1992 remote target when gdb connects to it. This is needed when you debug
1995 set remotebreak [on | off]
1997 Deprecated. Use "set/show remote interrupt-sequence" instead.
1999 tvariable $NAME [ = EXP ]
2000 Create or modify a trace state variable.
2003 List trace state variables and their values.
2005 delete tvariable $NAME ...
2006 Delete one or more trace state variables.
2009 Evaluate the given expressions without collecting anything into the
2010 trace buffer. (Valid in tracepoint actions only.)
2012 ftrace FN / FILE:LINE / *ADDR
2013 Define a fast tracepoint at the given function, line, or address.
2015 * New expression syntax
2017 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2018 GDB now parses 0b101010 identically with 42.
2022 set follow-exec-mode new|same
2023 show follow-exec-mode
2024 Control whether GDB reuses the same inferior across an exec call or
2025 creates a new one. This is useful to be able to restart the old
2026 executable after the inferior having done an exec call.
2028 set default-collect EXPR, ...
2029 show default-collect
2030 Define a list of expressions to be collected at each tracepoint.
2031 This is a useful way to ensure essential items are not overlooked,
2032 such as registers or a critical global variable.
2034 set disconnected-tracing
2035 show disconnected-tracing
2036 If set to 1, the target is instructed to continue tracing if it
2037 loses its connection to GDB. If 0, the target is to stop tracing
2040 set circular-trace-buffer
2041 show circular-trace-buffer
2042 If set to on, the target is instructed to use a circular trace buffer
2043 and discard the oldest trace frames instead of stopping the trace due
2044 to a full trace buffer. If set to off, the trace stops when the buffer
2045 fills up. Some targets may not support this.
2047 set script-extension off|soft|strict
2048 show script-extension
2049 If set to "off", the debugger does not perform any script language
2050 recognition, and all sourced files are assumed to be GDB scripts.
2051 If set to "soft" (the default), files are sourced according to
2052 filename extension, falling back to GDB scripts if the first
2054 If set to "strict", files are sourced according to filename extension.
2056 set ada trust-PAD-over-XVS on|off
2057 show ada trust-PAD-over-XVS
2058 If off, activate a workaround against a bug in the debugging information
2059 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2060 the GCC sources for more information about the GNAT encoding and
2061 PAD types in particular). It is always safe to set this option to
2062 off, but this introduces a slight performance penalty. The default
2065 * Python API Improvements
2067 ** GDB provides the new class gdb.LazyString. This is useful in
2068 some pretty-printing cases. The new method gdb.Value.lazy_string
2069 provides a simple way to create objects of this type.
2071 ** The fields returned by gdb.Type.fields now have an
2072 `is_base_class' attribute.
2074 ** The new method gdb.Type.range returns the range of an array type.
2076 ** The new method gdb.parse_and_eval can be used to parse and
2077 evaluate an expression.
2079 * New remote packets
2082 Define a trace state variable.
2085 Get the current value of a trace state variable.
2088 Set desired tracing behavior upon disconnection.
2091 Set the trace buffer to be linear or circular.
2094 Get data about the tracepoints currently in use.
2098 Process record now works correctly with hardware watchpoints.
2100 Multiple bug fixes have been made to the mips-irix port, making it
2101 much more reliable. In particular:
2102 - Debugging threaded applications is now possible again. Previously,
2103 GDB would hang while starting the program, or while waiting for
2104 the program to stop at a breakpoint.
2105 - Attaching to a running process no longer hangs.
2106 - An error occurring while loading a core file has been fixed.
2107 - Changing the value of the PC register now works again. This fixes
2108 problems observed when using the "jump" command, or when calling
2109 a function from GDB, or even when assigning a new value to $pc.
2110 - With the "finish" and "return" commands, the return value for functions
2111 returning a small array is now correctly printed.
2112 - It is now possible to break on shared library code which gets executed
2113 during a shared library init phase (code executed while executing
2114 their .init section). Previously, the breakpoint would have no effect.
2115 - GDB is now able to backtrace through the signal handler for
2116 non-threaded programs.
2118 PIE (Position Independent Executable) programs debugging is now supported.
2119 This includes debugging execution of PIC (Position Independent Code) shared
2120 libraries although for that, it should be possible to run such libraries as an
2123 *** Changes in GDB 7.0
2125 * GDB now has an interface for JIT compilation. Applications that
2126 dynamically generate code can create symbol files in memory and register
2127 them with GDB. For users, the feature should work transparently, and
2128 for JIT developers, the interface is documented in the GDB manual in the
2129 "JIT Compilation Interface" chapter.
2131 * Tracepoints may now be conditional. The syntax is as for
2132 breakpoints; either an "if" clause appended to the "trace" command,
2133 or the "condition" command is available. GDB sends the condition to
2134 the target for evaluation using the same bytecode format as is used
2135 for tracepoint actions.
2137 * The disassemble command now supports: an optional /r modifier, print the
2138 raw instructions in hex as well as in symbolic form, and an optional /m
2139 modifier to print mixed source+assembly.
2141 * Process record and replay
2143 In a architecture environment that supports ``process record and
2144 replay'', ``process record and replay'' target can record a log of
2145 the process execution, and replay it with both forward and reverse
2148 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2149 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2150 set execution-direction {forward|reverse}, for targets that support
2153 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2154 feature is available with a native GDB running on kernel version
2157 * GDB now has support for multi-byte and wide character sets on the
2158 target. Strings whose character type is wchar_t, char16_t, or
2159 char32_t are now correctly printed. GDB supports wide- and unicode-
2160 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2161 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2162 `printf'. This feature requires iconv to work properly; if your
2163 system does not have a working iconv, GDB can use GNU libiconv. See
2164 the installation instructions for more information.
2166 * GDB now supports automatic retrieval of shared library files from
2167 remote targets. To use this feature, specify a system root that begins
2168 with the `remote:' prefix, either via the `set sysroot' command or via
2169 the `--with-sysroot' configure-time option.
2171 * "info sharedlibrary" now takes an optional regex of libraries to show,
2172 and it now reports if a shared library has no debugging information.
2174 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2175 now complete on file names.
2177 * When completing in expressions, gdb will attempt to limit
2178 completions to allowable structure or union fields, where appropriate.
2179 For instance, consider:
2181 # struct example { int f1; double f2; };
2182 # struct example variable;
2185 If the user types TAB at the end of this command line, the available
2186 completions will be "f1" and "f2".
2188 * Inlined functions are now supported. They show up in backtraces, and
2189 the "step", "next", and "finish" commands handle them automatically.
2191 * GDB now supports the token-splicing (##) and stringification (#)
2192 operators when expanding macros. It also supports variable-arity
2195 * GDB now supports inspecting extra signal information, exported by
2196 the new $_siginfo convenience variable. The feature is currently
2197 implemented on linux ARM, i386 and amd64.
2199 * GDB can now display the VFP floating point registers and NEON vector
2200 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2201 can provide these registers (requires Linux 2.6.30 or later). Remote
2202 and simulator targets may also provide them.
2204 * New remote packets
2207 Search memory for a sequence of bytes.
2210 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2211 operation over reliable transport links. Use of this packet is
2212 controlled by the `set remote noack-packet' command.
2215 Kill the process with the specified process ID. Use this in preference
2216 to `k' when multiprocess protocol extensions are supported.
2219 Obtains additional operating system information
2223 Read or write additional signal information.
2225 * Removed remote protocol undocumented extension
2227 An undocumented extension to the remote protocol's `S' stop reply
2228 packet that permited the stub to pass a process id was removed.
2229 Remote servers should use the `T' stop reply packet instead.
2231 * GDB now supports multiple function calling conventions according to the
2232 DWARF-2 DW_AT_calling_convention function attribute.
2234 * The SH target utilizes the aforementioned change to distinguish between gcc
2235 and Renesas calling convention. It also adds the new CLI commands
2236 `set/show sh calling-convention'.
2238 * GDB can now read compressed debug sections, as produced by GNU gold
2239 with the --compress-debug-sections=zlib flag.
2241 * 64-bit core files are now supported on AIX.
2243 * Thread switching is now supported on Tru64.
2245 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2246 which will be allocated using malloc later in program execution.
2248 * The qXfer:libraries:read remote procotol packet now allows passing a
2249 list of section offsets.
2251 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2252 conditions handling signals delivered during attach or thread creation
2253 have also been fixed.
2255 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2256 From the user's standpoint, all unqualified instances of True and False
2257 are treated as the standard definitions, regardless of context.
2259 * GDB now parses C++ symbol and type names more flexibly. For
2262 template<typename T> class C { };
2265 GDB will now correctly handle all of:
2267 ptype C<char const *>
2268 ptype C<char const*>
2269 ptype C<const char *>
2270 ptype C<const char*>
2272 * New features in the GDB remote stub, gdbserver
2274 - The "--wrapper" command-line argument tells gdbserver to use a
2275 wrapper program to launch programs for debugging.
2277 - On PowerPC and S/390 targets, it is now possible to use a single
2278 gdbserver executable to debug both 32-bit and 64-bit programs.
2279 (This requires gdbserver itself to be built as a 64-bit executable.)
2281 - gdbserver uses the new noack protocol mode for TCP connections to
2282 reduce communications latency, if also supported and enabled in GDB.
2284 - Support for the sparc64-linux-gnu target is now included in
2287 - The amd64-linux build of gdbserver now supports debugging both
2288 32-bit and 64-bit programs.
2290 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2291 now support hardware watchpoints, and will use them automatically
2296 GDB now has support for scripting using Python. Whether this is
2297 available is determined at configure time.
2299 New GDB commands can now be written in Python.
2301 * Ada tasking support
2303 Ada tasks can now be inspected in GDB. The following commands have
2307 Print the list of Ada tasks.
2309 Print detailed information about task number N.
2311 Print the task number of the current task.
2313 Switch the context of debugging to task number N.
2315 * Support for user-defined prefixed commands. The "define" command can
2316 add new commands to existing prefixes, e.g. "target".
2318 * Multi-inferior, multi-process debugging.
2320 GDB now has generalized support for multi-inferior debugging. See
2321 "Debugging Multiple Inferiors" in the manual for more information.
2322 Although availability still depends on target support, the command
2323 set is more uniform now. The GNU/Linux specific multi-forks support
2324 has been migrated to this new framework. This implied some user
2325 visible changes; see "New commands" and also "Removed commands"
2328 * Target descriptions can now describe the target OS ABI. See the
2329 "Target Description Format" section in the user manual for more
2332 * Target descriptions can now describe "compatible" architectures
2333 to indicate that the target can execute applications for a different
2334 architecture in addition to those for the main target architecture.
2335 See the "Target Description Format" section in the user manual for
2338 * Multi-architecture debugging.
2340 GDB now includes general supports for debugging applications on
2341 hybrid systems that use more than one single processor architecture
2342 at the same time. Each such hybrid architecture still requires
2343 specific support to be added. The only hybrid architecture supported
2344 in this version of GDB is the Cell Broadband Engine.
2346 * GDB now supports integrated debugging of Cell/B.E. applications that
2347 use both the PPU and SPU architectures. To enable support for hybrid
2348 Cell/B.E. debugging, you need to configure GDB to support both the
2349 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2350 --enable-targets configure option.
2352 * Non-stop mode debugging.
2354 For some targets, GDB now supports an optional mode of operation in
2355 which you can examine stopped threads while other threads continue
2356 to execute freely. This is referred to as non-stop mode, with the
2357 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2358 section in the user manual for more information.
2360 To be able to support remote non-stop debugging, a remote stub needs
2361 to implement the non-stop mode remote protocol extensions, as
2362 described in the "Remote Non-Stop" section of the user manual. The
2363 GDB remote stub, gdbserver, has been adjusted to support these
2364 extensions on linux targets.
2366 * New commands (for set/show, see "New options" below)
2368 catch syscall [NAME(S) | NUMBER(S)]
2369 Catch system calls. Arguments, which should be names of system
2370 calls or their numbers, mean catch only those syscalls. Without
2371 arguments, every syscall will be caught. When the inferior issues
2372 any of the specified syscalls, GDB will stop and announce the system
2373 call, both when it is called and when its call returns. This
2374 feature is currently available with a native GDB running on the
2375 Linux Kernel, under the following architectures: x86, x86_64,
2376 PowerPC and PowerPC64.
2378 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2380 Search memory for a sequence of bytes.
2382 maint set python print-stack
2383 maint show python print-stack
2384 Show a stack trace when an error is encountered in a Python script.
2387 Invoke CODE by passing it to the Python interpreter.
2392 These allow macros to be defined, undefined, and listed
2396 Show operating system information about processes.
2399 List the inferiors currently under GDB's control.
2402 Switch focus to inferior number NUM.
2405 Detach from inferior number NUM.
2408 Kill inferior number NUM.
2412 set spu stop-on-load
2413 show spu stop-on-load
2414 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2416 set spu auto-flush-cache
2417 show spu auto-flush-cache
2418 Control whether to automatically flush the software-managed cache
2419 during Cell/B.E. debugging.
2421 set sh calling-convention
2422 show sh calling-convention
2423 Control the calling convention used when calling SH target functions.
2426 show debug timestamp
2427 Control display of timestamps with GDB debugging output.
2429 set disassemble-next-line
2430 show disassemble-next-line
2431 Control display of disassembled source lines or instructions when
2434 set remote noack-packet
2435 show remote noack-packet
2436 Set/show the use of remote protocol QStartNoAckMode packet. See above
2437 under "New remote packets."
2439 set remote query-attached-packet
2440 show remote query-attached-packet
2441 Control use of remote protocol `qAttached' (query-attached) packet.
2443 set remote read-siginfo-object
2444 show remote read-siginfo-object
2445 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2448 set remote write-siginfo-object
2449 show remote write-siginfo-object
2450 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2453 set remote reverse-continue
2454 show remote reverse-continue
2455 Control use of remote protocol 'bc' (reverse-continue) packet.
2457 set remote reverse-step
2458 show remote reverse-step
2459 Control use of remote protocol 'bs' (reverse-step) packet.
2461 set displaced-stepping
2462 show displaced-stepping
2463 Control displaced stepping mode. Displaced stepping is a way to
2464 single-step over breakpoints without removing them from the debuggee.
2465 Also known as "out-of-line single-stepping".
2468 show debug displaced
2469 Control display of debugging info for displaced stepping.
2471 maint set internal-error
2472 maint show internal-error
2473 Control what GDB does when an internal error is detected.
2475 maint set internal-warning
2476 maint show internal-warning
2477 Control what GDB does when an internal warning is detected.
2482 Use a wrapper program to launch programs for debugging.
2484 set multiple-symbols (all|ask|cancel)
2485 show multiple-symbols
2486 The value of this variable can be changed to adjust the debugger behavior
2487 when an expression or a breakpoint location contains an ambiguous symbol
2488 name (an overloaded function name, for instance).
2490 set breakpoint always-inserted
2491 show breakpoint always-inserted
2492 Keep breakpoints always inserted in the target, as opposed to inserting
2493 them when resuming the target, and removing them when the target stops.
2494 This option can improve debugger performance on slow remote targets.
2496 set arm fallback-mode (arm|thumb|auto)
2497 show arm fallback-mode
2498 set arm force-mode (arm|thumb|auto)
2500 These commands control how ARM GDB determines whether instructions
2501 are ARM or Thumb. The default for both settings is auto, which uses
2502 the current CPSR value for instructions without symbols; previous
2503 versions of GDB behaved as if "set arm fallback-mode arm".
2505 set disable-randomization
2506 show disable-randomization
2507 Standalone programs run with the virtual address space randomization enabled
2508 by default on some platforms. This option keeps the addresses stable across
2509 multiple debugging sessions.
2513 Control whether other threads are stopped or not when some thread hits
2518 Requests that asynchronous execution is enabled in the target, if available.
2519 In this case, it's possible to resume target in the background, and interact
2520 with GDB while the target is running. "show target-async" displays the
2521 current state of asynchronous execution of the target.
2523 set target-wide-charset
2524 show target-wide-charset
2525 The target-wide-charset is the name of the character set that GDB
2526 uses when printing characters whose type is wchar_t.
2528 set tcp auto-retry (on|off)
2530 set tcp connect-timeout
2531 show tcp connect-timeout
2532 These commands allow GDB to retry failed TCP connections to a remote stub
2533 with a specified timeout period; this is useful if the stub is launched
2534 in parallel with GDB but may not be ready to accept connections immediately.
2536 set libthread-db-search-path
2537 show libthread-db-search-path
2538 Control list of directories which GDB will search for appropriate
2541 set schedule-multiple (on|off)
2542 show schedule-multiple
2543 Allow GDB to resume all threads of all processes or only threads of
2544 the current process.
2548 Use more aggressive caching for accesses to the stack. This improves
2549 performance of remote debugging (particularly backtraces) without
2550 affecting correctness.
2552 set interactive-mode (on|off|auto)
2553 show interactive-mode
2554 Control whether GDB runs in interactive mode (on) or not (off).
2555 When in interactive mode, GDB waits for the user to answer all
2556 queries. Otherwise, GDB does not wait and assumes the default
2557 answer. When set to auto (the default), GDB determines which
2558 mode to use based on the stdin settings.
2563 For program forks, this is replaced by the new more generic `info
2564 inferiors' command. To list checkpoints, you can still use the
2565 `info checkpoints' command, which was an alias for the `info forks'
2569 Replaced by the new `inferior' command. To switch between
2570 checkpoints, you can still use the `restart' command, which was an
2571 alias for the `fork' command.
2574 This is removed, since some targets don't have a notion of
2575 processes. To switch between processes, you can still use the
2576 `inferior' command using GDB's own inferior number.
2579 For program forks, this is replaced by the new more generic `kill
2580 inferior' command. To delete a checkpoint, you can still use the
2581 `delete checkpoint' command, which was an alias for the `delete
2585 For program forks, this is replaced by the new more generic `detach
2586 inferior' command. To detach a checkpoint, you can still use the
2587 `detach checkpoint' command, which was an alias for the `detach
2590 * New native configurations
2592 x86/x86_64 Darwin i[34567]86-*-darwin*
2594 x86_64 MinGW x86_64-*-mingw*
2598 Lattice Mico32 lm32-*
2599 x86 DICOS i[34567]86-*-dicos*
2600 x86_64 DICOS x86_64-*-dicos*
2603 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2604 (mingw32ce) debugging.
2610 These commands were actually not implemented on any target.
2612 *** Changes in GDB 6.8
2614 * New native configurations
2616 NetBSD/hppa hppa*-*netbsd*
2617 Xtensa GNU/Linux xtensa*-*-linux*
2621 NetBSD/hppa hppa*-*-netbsd*
2622 Xtensa GNU/Lunux xtensa*-*-linux*
2624 * Change in command line behavior -- corefiles vs. process ids.
2626 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2627 attaching to process NUMBER fails, GDB no longer attempts to open a
2628 core file named NUMBER. Attaching to a program using the -c option
2629 is no longer supported. Instead, use the '-p' or '--pid' options.
2631 * GDB can now be built as a native debugger for debugging Windows x86
2632 (mingw32) Portable Executable (PE) programs.
2634 * Pending breakpoints no longer change their number when their address
2637 * GDB now supports breakpoints with multiple locations,
2638 including breakpoints on C++ constructors, inside C++ templates,
2639 and in inlined functions.
2641 * GDB's ability to debug optimized code has been improved. GDB more
2642 accurately identifies function bodies and lexical blocks that occupy
2643 more than one contiguous range of addresses.
2645 * Target descriptions can now describe registers for PowerPC.
2647 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2648 registers on PowerPC targets.
2650 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2651 targets even when the libthread_db library is not available.
2653 * The GDB remote stub, gdbserver, now supports the new file transfer
2654 commands (remote put, remote get, and remote delete).
2656 * The GDB remote stub, gdbserver, now supports run and attach in
2657 extended-remote mode.
2659 * hppa*64*-*-hpux11* target broken
2660 The debugger is unable to start a program and fails with the following
2661 error: "Error trying to get information about dynamic linker".
2662 The gdb-6.7 release is also affected.
2664 * GDB now supports the --enable-targets= configure option to allow
2665 building a single GDB executable that supports multiple remote
2666 target architectures.
2668 * GDB now supports debugging C and C++ programs which use the
2669 Decimal Floating Point extension. In addition, the PowerPC target
2670 now has a set of pseudo-registers to inspect decimal float values
2671 stored in two consecutive float registers.
2673 * The -break-insert MI command can optionally create pending
2676 * Improved support for debugging Ada
2677 Many improvements to the Ada language support have been made. These
2679 - Better support for Ada2005 interface types
2680 - Improved handling of arrays and slices in general
2681 - Better support for Taft-amendment types
2682 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2684 - Improved command completion in Ada
2687 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2692 set print frame-arguments (all|scalars|none)
2693 show print frame-arguments
2694 The value of this variable can be changed to control which argument
2695 values should be printed by the debugger when displaying a frame.
2700 Transfer files to and from a remote target, and delete remote files.
2707 Transfer files to and from a remote target, and delete remote files.
2709 * New remote packets
2716 Open, close, read, write, and delete files on the remote system.
2719 Attach to an existing process on the remote system, in extended-remote
2723 Run a new process on the remote system, in extended-remote mode.
2725 *** Changes in GDB 6.7
2727 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2728 bfd, libiberty and opcodes, as revealed by static analysis donated by
2729 Coverity, Inc. (http://scan.coverity.com).
2731 * When looking up multiply-defined global symbols, GDB will now prefer the
2732 symbol definition in the current shared library if it was built using the
2733 -Bsymbolic linker option.
2735 * When the Text User Interface (TUI) is not configured, GDB will now
2736 recognize the -tui command-line option and print a message that the TUI
2739 * The GDB remote stub, gdbserver, now has lower overhead for high
2740 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2742 * GDB for MIPS targets now autodetects whether a remote target provides
2743 32-bit or 64-bit register values.
2745 * Support for C++ member pointers has been improved.
2747 * GDB now understands XML target descriptions, which specify the
2748 target's overall architecture. GDB can read a description from
2749 a local file or over the remote serial protocol.
2751 * Vectors of single-byte data use a new integer type which is not
2752 automatically displayed as character or string data.
2754 * The /s format now works with the print command. It displays
2755 arrays of single-byte integers and pointers to single-byte integers
2758 * Target descriptions can now describe target-specific registers,
2759 for architectures which have implemented the support (currently
2760 only ARM, M68K, and MIPS).
2762 * GDB and the GDB remote stub, gdbserver, now support the XScale
2765 * The GDB remote stub, gdbserver, has been updated to support
2766 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2767 has been rewritten to use the standard GDB remote protocol.
2769 * GDB can now step into C++ functions which are called through thunks.
2771 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2773 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2774 layout. It also supports a TextSeg= and DataSeg= response when only
2775 segment base addresses (rather than offsets) are available.
2777 * The /i format now outputs any trailing branch delay slot instructions
2778 immediately following the last instruction within the count specified.
2780 * The GDB remote protocol "T" stop reply packet now supports a
2781 "library" response. Combined with the new "qXfer:libraries:read"
2782 packet, this response allows GDB to debug shared libraries on targets
2783 where the operating system manages the list of loaded libraries (e.g.
2784 Windows and SymbianOS).
2786 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2787 (DLLs) on Windows and Windows CE targets.
2789 * GDB now supports a faster verification that a .debug file matches its binary
2790 according to its build-id signature, if the signature is present.
2796 Enable or disable hardware flow control (RTS/CTS) on the serial port
2797 when debugging using remote targets.
2799 set mem inaccessible-by-default
2800 show mem inaccessible-by-default
2801 If the target supplies a memory map, for instance via the remote
2802 protocol's "qXfer:memory-map:read" packet, setting this variable
2803 prevents GDB from accessing memory outside the memory map. This
2804 is useful for targets with memory mapped registers or which react
2805 badly to accesses of unmapped address space.
2807 set breakpoint auto-hw
2808 show breakpoint auto-hw
2809 If the target supplies a memory map, for instance via the remote
2810 protocol's "qXfer:memory-map:read" packet, setting this variable
2811 lets GDB use hardware breakpoints automatically for memory regions
2812 where it can not use software breakpoints. This covers both the
2813 "break" command and internal breakpoints used for other commands
2814 including "next" and "finish".
2817 catch exception unhandled
2818 Stop the program execution when Ada exceptions are raised.
2821 Stop the program execution when an Ada assertion failed.
2825 Set an alternate system root for target files. This is a more
2826 general version of "set solib-absolute-prefix", which is now
2827 an alias to "set sysroot".
2830 Provide extended SPU facility status information. This set of
2831 commands is available only when debugging the Cell/B.E. SPU
2834 * New native configurations
2836 OpenBSD/sh sh*-*openbsd*
2839 unset tdesc filename
2841 Use the specified local file as an XML target description, and do
2842 not query the target for its built-in description.
2846 OpenBSD/sh sh*-*-openbsd*
2847 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2848 Toshiba Media Processor mep-elf
2850 * New remote packets
2853 Ignore the specified signals; pass them directly to the debugged program
2854 without stopping other threads or reporting them to GDB.
2856 qXfer:features:read:
2857 Read an XML target description from the target, which describes its
2862 Read or write contents of an spufs file on the target system. These
2863 packets are available only on the Cell/B.E. SPU architecture.
2865 qXfer:libraries:read:
2866 Report the loaded shared libraries. Combined with new "T" packet
2867 response, this packet allows GDB to debug shared libraries on
2868 targets where the operating system manages the list of loaded
2869 libraries (e.g. Windows and SymbianOS).
2873 Support for these obsolete configurations has been removed.
2881 i[34567]86-*-lynxos*
2882 i[34567]86-*-netware*
2883 i[34567]86-*-sco3.2v5*
2884 i[34567]86-*-sco3.2v4*
2886 i[34567]86-*-sysv4.2*
2889 i[34567]86-*-unixware2*
2890 i[34567]86-*-unixware*
2899 * Other removed features
2906 Various m68k-only ROM monitors.
2913 Various Renesas ROM monitors and debugging interfaces for SH and
2918 Support for a Macraigor serial interface to on-chip debugging.
2919 GDB does not directly support the newer parallel or USB
2924 A debug information format. The predecessor to DWARF 2 and
2925 DWARF 3, which are still supported.
2927 Support for the HP aCC compiler on HP-UX/PA-RISC
2929 SOM-encapsulated symbolic debugging information, automatic
2930 invocation of pxdb, and the aCC custom C++ ABI. This does not
2931 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2932 with aCC can still be debugged on an assembly level.
2934 MIPS ".pdr" sections
2936 A MIPS-specific format used to describe stack frame layout
2937 in debugging information.
2941 GDB could work with an older version of Guile to debug
2942 the interpreter and Scheme programs running in it.
2944 set mips stack-arg-size
2945 set mips saved-gpreg-size
2947 Use "set mips abi" to control parameter passing for MIPS.
2949 *** Changes in GDB 6.6
2954 Cell Broadband Engine SPU spu-elf
2956 * GDB can now be configured as a cross-debugger targeting native Windows
2957 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2958 running on a Windows system over TCP/IP to debug Windows programs.
2960 * The GDB remote stub, gdbserver, has been updated to support Windows and
2961 Cygwin debugging. Both single-threaded and multi-threaded programs are
2964 * The "set trust-readonly-sections" command works again. This command was
2965 broken in GDB 6.3, 6.4, and 6.5.
2967 * The "load" command now supports writing to flash memory, if the remote
2968 stub provides the required support.
2970 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2971 longer requires symbolic debug information (e.g. DWARF-2).
2976 unset substitute-path
2977 show substitute-path
2978 Manage a list of substitution rules that GDB uses to rewrite the name
2979 of the directories where the sources are located. This can be useful
2980 for instance when the sources were moved to a different location
2981 between compilation and debugging.
2985 Print each CLI command as it is executed. Each command is prefixed with
2986 a number of `+' symbols representing the nesting depth.
2987 The source command now has a `-v' option to enable the same feature.
2991 The ARM Demon monitor support (RDP protocol, "target rdp").
2993 Kernel Object Display, an embedded debugging feature which only worked with
2994 an obsolete version of Cisco IOS.
2996 The 'set download-write-size' and 'show download-write-size' commands.
2998 * New remote packets
3001 Tell a stub about GDB client features, and request remote target features.
3002 The first feature implemented is PacketSize, which allows the target to
3003 specify the size of packets it can handle - to minimize the number of
3004 packets required and improve performance when connected to a remote
3008 Fetch an OS auxilliary vector from the remote stub. This packet is a
3009 more efficient replacement for qPart:auxv:read.
3011 qXfer:memory-map:read:
3012 Fetch a memory map from the remote stub, including information about
3013 RAM, ROM, and flash memory devices.
3018 Erase and program a flash memory device.
3020 * Removed remote packets
3023 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3024 used it, and only gdbserver implemented it.
3026 *** Changes in GDB 6.5
3030 Renesas M32C/M16C m32c-elf
3032 Morpho Technologies ms1 ms1-elf
3036 init-if-undefined Initialize a convenience variable, but
3037 only if it doesn't already have a value.
3039 The following commands are presently only implemented for native GNU/Linux:
3041 checkpoint Save a snapshot of the program state.
3043 restart <n> Return the program state to a
3044 previously saved state.
3046 info checkpoints List currently saved checkpoints.
3048 delete-checkpoint <n> Delete a previously saved checkpoint.
3050 set|show detach-on-fork Tell gdb whether to detach from a newly
3051 forked process, or to keep debugging it.
3053 info forks List forks of the user program that
3054 are available to be debugged.
3056 fork <n> Switch to debugging one of several
3057 forks of the user program that are
3058 available to be debugged.
3060 delete-fork <n> Delete a fork from the list of forks
3061 that are available to be debugged (and
3062 kill the forked process).
3064 detach-fork <n> Delete a fork from the list of forks
3065 that are available to be debugged (and
3066 allow the process to continue).
3070 Morpho Technologies ms2 ms1-elf
3072 * Improved Windows host support
3074 GDB now builds as a cross debugger hosted on i686-mingw32, including
3075 native console support, and remote communications using either
3076 network sockets or serial ports.
3078 * Improved Modula-2 language support
3080 GDB can now print most types in the Modula-2 syntax. This includes:
3081 basic types, set types, record types, enumerated types, range types,
3082 pointer types and ARRAY types. Procedure var parameters are correctly
3083 printed and hexadecimal addresses and character constants are also
3084 written in the Modula-2 syntax. Best results can be obtained by using
3085 GNU Modula-2 together with the -gdwarf-2 command line option.
3089 The ARM rdi-share module.
3091 The Netware NLM debug server.
3093 *** Changes in GDB 6.4
3095 * New native configurations
3097 OpenBSD/arm arm*-*-openbsd*
3098 OpenBSD/mips64 mips64-*-openbsd*
3102 Morpho Technologies ms1 ms1-elf
3104 * New command line options
3106 --batch-silent As for --batch, but totally silent.
3107 --return-child-result The debugger will exist with the same value
3108 the child (debugged) program exited with.
3109 --eval-command COMMAND, -ex COMMAND
3110 Execute a single GDB CLI command. This may be
3111 specified multiple times and in conjunction
3112 with the --command (-x) option.
3114 * Deprecated commands removed
3116 The following commands, that were deprecated in 2000, have been
3120 set|show arm disassembly-flavor set|show arm disassembler
3121 othernames set arm disassembler
3122 set|show remotedebug set|show debug remote
3123 set|show archdebug set|show debug arch
3124 set|show eventdebug set|show debug event
3127 * New BSD user-level threads support
3129 It is now possible to debug programs using the user-level threads
3130 library on OpenBSD and FreeBSD. Currently supported (target)
3133 FreeBSD/amd64 x86_64-*-freebsd*
3134 FreeBSD/i386 i386-*-freebsd*
3135 OpenBSD/i386 i386-*-openbsd*
3137 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3138 are not yet supported.
3140 * New support for Matsushita MN10300 w/sim added
3141 (Work in progress). mn10300-elf.
3143 * REMOVED configurations and files
3145 VxWorks and the XDR protocol *-*-vxworks
3146 Motorola MCORE mcore-*-*
3147 National Semiconductor NS32000 ns32k-*-*
3149 * New "set print array-indexes" command
3151 After turning this setting "on", GDB prints the index of each element
3152 when displaying arrays. The default is "off" to preserve the previous
3155 * VAX floating point support
3157 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3159 * User-defined command support
3161 In addition to using $arg0..$arg9 for argument passing, it is now possible
3162 to use $argc to determine now many arguments have been passed. See the
3163 section on user-defined commands in the user manual for more information.
3165 *** Changes in GDB 6.3:
3167 * New command line option
3169 GDB now accepts -l followed by a number to set the timeout for remote
3172 * GDB works with GCC -feliminate-dwarf2-dups
3174 GDB now supports a more compact representation of DWARF-2 debug
3175 information using DW_FORM_ref_addr references. These are produced
3176 by GCC with the option -feliminate-dwarf2-dups and also by some
3177 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3178 to use -feliminate-dwarf2-dups.
3180 * Internationalization
3182 When supported by the host system, GDB will be built with
3183 internationalization (libintl). The task of marking up the sources is
3184 continued, we're looking forward to our first translation.
3188 Initial support for debugging programs compiled with the GNAT
3189 implementation of the Ada programming language has been integrated
3190 into GDB. In this release, support is limited to expression evaluation.
3192 * New native configurations
3194 GNU/Linux/m32r m32r-*-linux-gnu
3198 GDB's remote protocol now includes support for the 'p' packet. This
3199 packet is used to fetch individual registers from a remote inferior.
3201 * END-OF-LIFE registers[] compatibility module
3203 GDB's internal register infrastructure has been completely rewritten.
3204 The new infrastructure making possible the implementation of key new
3205 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3208 GDB 6.3 will be the last release to include the the registers[]
3209 compatibility module that allowed out-of-date configurations to
3210 continue to work. This change directly impacts the following
3220 powerpc bdm protocol
3222 Unless there is activity to revive these configurations, they will be
3223 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3225 * OBSOLETE configurations and files
3227 Configurations that have been declared obsolete in this release have
3228 been commented out. Unless there is activity to revive these
3229 configurations, the next release of GDB will have their sources
3230 permanently REMOVED.
3239 *** Changes in GDB 6.2.1:
3241 * MIPS `break main; run' gave an heuristic-fence-post warning
3243 When attempting to run even a simple program, a warning about
3244 heuristic-fence-post being hit would be reported. This problem has
3247 * MIPS IRIX 'long double' crashed GDB
3249 When examining a long double variable, GDB would get a segmentation
3250 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3251 IRIX long double values).
3255 A bug in the VAX stack code was causing problems with the "next"
3256 command. This problem has been fixed.
3258 *** Changes in GDB 6.2:
3260 * Fix for ``many threads''
3262 On GNU/Linux systems that use the NPTL threads library, a program
3263 rapidly creating and deleting threads would confuse GDB leading to the
3266 ptrace: No such process.
3267 thread_db_get_info: cannot get thread info: generic error
3269 This problem has been fixed.
3271 * "-async" and "-noasync" options removed.
3273 Support for the broken "-noasync" option has been removed (it caused
3276 * New ``start'' command.
3278 This command runs the program until the begining of the main procedure.
3280 * New BSD Kernel Data Access Library (libkvm) interface
3282 Using ``target kvm'' it is now possible to debug kernel core dumps and
3283 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3284 platforms. Currently supported (native-only) configurations are:
3286 FreeBSD/amd64 x86_64-*-freebsd*
3287 FreeBSD/i386 i?86-*-freebsd*
3288 NetBSD/i386 i?86-*-netbsd*
3289 NetBSD/m68k m68*-*-netbsd*
3290 NetBSD/sparc sparc-*-netbsd*
3291 OpenBSD/amd64 x86_64-*-openbsd*
3292 OpenBSD/i386 i?86-*-openbsd*
3293 OpenBSD/m68k m68*-openbsd*
3294 OpenBSD/sparc sparc-*-openbsd*
3296 * Signal trampoline code overhauled
3298 Many generic problems with GDB's signal handling code have been fixed.
3299 These include: backtraces through non-contiguous stacks; recognition
3300 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3301 call; backtrace through a signal trampoline; step into and out of
3302 signal handlers; and single-stepping in the signal trampoline.
3304 Please note that kernel bugs are a limiting factor here. These
3305 features have been shown to work on an s390 GNU/Linux system that
3306 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3308 * Cygwin support for DWARF 2 added.
3310 * New native configurations
3312 GNU/Linux/hppa hppa*-*-linux*
3313 OpenBSD/hppa hppa*-*-openbsd*
3314 OpenBSD/m68k m68*-*-openbsd*
3315 OpenBSD/m88k m88*-*-openbsd*
3316 OpenBSD/powerpc powerpc-*-openbsd*
3317 NetBSD/vax vax-*-netbsd*
3318 OpenBSD/vax vax-*-openbsd*
3320 * END-OF-LIFE frame compatibility module
3322 GDB's internal frame infrastructure has been completely rewritten.
3323 The new infrastructure making it possible to support key new features
3324 including DWARF 2 Call Frame Information. To aid in the task of
3325 migrating old configurations to this new infrastructure, a
3326 compatibility module, that allowed old configurations to continue to
3327 work, was also included.
3329 GDB 6.2 will be the last release to include this frame compatibility
3330 module. This change directly impacts the following configurations:
3340 Unless there is activity to revive these configurations, they will be
3341 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3343 * REMOVED configurations and files
3345 Sun 3, running SunOS 3 m68*-*-sunos3*
3346 Sun 3, running SunOS 4 m68*-*-sunos4*
3347 Sun 2, running SunOS 3 m68000-*-sunos3*
3348 Sun 2, running SunOS 4 m68000-*-sunos4*
3349 Motorola 680x0 running LynxOS m68*-*-lynxos*
3350 AT&T 3b1/Unix pc m68*-att-*
3351 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3352 decstation mips-dec-* mips-little-*
3353 riscos mips-*-riscos* mips-*-sysv*
3354 sonymips mips-sony-*
3355 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3357 *** Changes in GDB 6.1.1:
3359 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3361 The TUI (Text-mode User Interface) is now built as part of a default
3362 GDB configuration. It is enabled by either selecting the TUI with the
3363 command line option "-i=tui" or by running the separate "gdbtui"
3364 program. For more information on the TUI, see the manual "Debugging
3367 * Pending breakpoint support (also included in GDB 6.1)
3369 Support has been added to allow you to specify breakpoints in shared
3370 libraries that have not yet been loaded. If a breakpoint location
3371 cannot be found, and the "breakpoint pending" option is set to auto,
3372 GDB queries you if you wish to make the breakpoint pending on a future
3373 shared-library load. If and when GDB resolves the breakpoint symbol,
3374 the pending breakpoint is removed as one or more regular breakpoints
3377 Pending breakpoints are very useful for GCJ Java debugging.
3379 * Fixed ISO-C build problems
3381 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3382 non ISO-C code that stopped them being built using a more strict ISO-C
3383 compiler (e.g., IBM's C compiler).
3385 * Fixed build problem on IRIX 5
3387 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3388 wasn't able to compile compile on an IRIX 5 system.
3390 * Added execute permission to gdb/gdbserver/configure
3392 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3393 permission. This bug would cause configure to fail on a number of
3394 systems (Solaris, IRIX). Ref: server/519.
3396 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3398 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3399 has been updated to use constant array sizes.
3401 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3403 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3404 its generated DWARF Call Frame Info. This encoding was causing GDB to
3405 panic, that panic has been fixed. Ref: gdb/1628.
3407 * Fixed a problem when examining parameters in shared library code.
3409 When examining parameters in optimized shared library code generated
3410 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3411 not available''. GDB now correctly displays the variable's value.
3413 *** Changes in GDB 6.1:
3415 * Removed --with-mmalloc
3417 Support for the mmalloc memory manager has been removed, as it
3418 conflicted with the internal gdb byte cache.
3420 * Changes in AMD64 configurations
3422 The AMD64 target now includes the %cs and %ss registers. As a result
3423 the AMD64 remote protocol has changed; this affects the floating-point
3424 and SSE registers. If you rely on those registers for your debugging,
3425 you should upgrade gdbserver on the remote side.
3427 * Revised SPARC target
3429 The SPARC target has been completely revised, incorporating the
3430 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3431 support for LynxOS and SunOS 4 has been dropped. Calling functions
3432 from within GDB on operating systems with a non-executable stack
3433 (Solaris, OpenBSD) now works.
3437 GDB has a new C++ demangler which does a better job on the mangled
3438 names generated by current versions of g++. It also runs faster, so
3439 with this and other changes gdb should now start faster on large C++
3442 * DWARF 2 Location Expressions
3444 GDB support for location expressions has been extended to support function
3445 arguments and frame bases. Older versions of GDB could crash when they
3448 * C++ nested types and namespaces
3450 GDB's support for nested types and namespaces in C++ has been
3451 improved, especially if you use the DWARF 2 debugging format. (This
3452 is the default for recent versions of GCC on most platforms.)
3453 Specifically, if you have a class "Inner" defined within a class or
3454 namespace "Outer", then GDB realizes that the class's name is
3455 "Outer::Inner", not simply "Inner". This should greatly reduce the
3456 frequency of complaints about not finding RTTI symbols. In addition,
3457 if you are stopped at inside of a function defined within a namespace,
3458 GDB modifies its name lookup accordingly.
3460 * New native configurations
3462 NetBSD/amd64 x86_64-*-netbsd*
3463 OpenBSD/amd64 x86_64-*-openbsd*
3464 OpenBSD/alpha alpha*-*-openbsd*
3465 OpenBSD/sparc sparc-*-openbsd*
3466 OpenBSD/sparc64 sparc64-*-openbsd*
3468 * New debugging protocols
3470 M32R with SDI protocol m32r-*-elf*
3472 * "set prompt-escape-char" command deleted.
3474 The command "set prompt-escape-char" has been deleted. This command,
3475 and its very obscure effet on GDB's prompt, was never documented,
3476 tested, nor mentioned in the NEWS file.
3478 * OBSOLETE configurations and files
3480 Configurations that have been declared obsolete in this release have
3481 been commented out. Unless there is activity to revive these
3482 configurations, the next release of GDB will have their sources
3483 permanently REMOVED.
3485 Sun 3, running SunOS 3 m68*-*-sunos3*
3486 Sun 3, running SunOS 4 m68*-*-sunos4*
3487 Sun 2, running SunOS 3 m68000-*-sunos3*
3488 Sun 2, running SunOS 4 m68000-*-sunos4*
3489 Motorola 680x0 running LynxOS m68*-*-lynxos*
3490 AT&T 3b1/Unix pc m68*-att-*
3491 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3492 decstation mips-dec-* mips-little-*
3493 riscos mips-*-riscos* mips-*-sysv*
3494 sonymips mips-sony-*
3495 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3497 * REMOVED configurations and files
3499 SGI Irix-4.x mips-sgi-irix4 or iris4
3500 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3501 Z8000 simulator z8k-zilog-none or z8ksim
3502 Matsushita MN10200 w/simulator mn10200-*-*
3503 H8/500 simulator h8500-hitachi-hms or h8500hms
3504 HP/PA running BSD hppa*-*-bsd*
3505 HP/PA running OSF/1 hppa*-*-osf*
3506 HP/PA Pro target hppa*-*-pro*
3507 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3508 386BSD i[3456]86-*-bsd*
3509 Sequent family i[3456]86-sequent-sysv4*
3510 i[3456]86-sequent-sysv*
3511 i[3456]86-sequent-bsd*
3512 SPARC running LynxOS sparc-*-lynxos*
3513 SPARC running SunOS 4 sparc-*-sunos4*
3514 Tsqware Sparclet sparclet-*-*
3515 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3517 *** Changes in GDB 6.0:
3521 Support for debugging the Objective-C programming language has been
3522 integrated into GDB.
3524 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3526 DWARF 2's Call Frame Information makes available compiler generated
3527 information that more exactly describes the program's run-time stack.
3528 By using this information, GDB is able to provide more robust stack
3531 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3532 have been updated to use a new backtrace mechanism which includes
3533 DWARF 2 CFI support.
3537 GDB's remote protocol has been extended to include support for hosted
3538 file I/O (where the remote target uses GDB's file system). See GDB's
3539 remote protocol documentation for details.
3541 * All targets using the new architecture framework.
3543 All of GDB's targets have been updated to use the new internal
3544 architecture framework. The way is now open for future GDB releases
3545 to include cross-architecture native debugging support (i386 on amd64,
3548 * GNU/Linux's Thread Local Storage (TLS)
3550 GDB now includes support for for the GNU/Linux implementation of
3551 per-thread variables.
3553 * GNU/Linux's Native POSIX Thread Library (NPTL)
3555 GDB's thread code has been updated to work with either the new
3556 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3558 * Separate debug info.
3560 GDB, in conjunction with BINUTILS, now supports a mechanism for
3561 automatically loading debug information from a separate file. Instead
3562 of shipping full debug and non-debug versions of system libraries,
3563 system integrators can now instead ship just the stripped libraries
3564 and optional debug files.
3566 * DWARF 2 Location Expressions
3568 DWARF 2 Location Expressions allow the compiler to more completely
3569 describe the location of variables (even in optimized code) to the
3572 GDB now includes preliminary support for location expressions (support
3573 for DW_OP_piece is still missing).
3577 A number of long standing bugs that caused GDB to die while starting a
3578 Java application have been fixed. GDB's Java support is now
3579 considered "useable".
3581 * GNU/Linux support for fork, vfork, and exec.
3583 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3584 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3587 * GDB supports logging output to a file
3589 There are two new commands, "set logging" and "show logging", which can be
3590 used to capture GDB's output to a file.
3592 * The meaning of "detach" has changed for gdbserver
3594 The "detach" command will now resume the application, as documented. To
3595 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3598 * d10v, m68hc11 `regs' command deprecated
3600 The `info registers' command has been updated so that it displays the
3601 registers using a format identical to the old `regs' command.
3605 A new command, "maint set profile on/off", has been added. This command can
3606 be used to enable or disable profiling while running GDB, to profile a
3607 session or a set of commands. In addition there is a new configure switch,
3608 "--enable-profiling", which will cause GDB to be compiled with profiling
3609 data, for more informative profiling results.
3611 * Default MI syntax changed to "mi2".
3613 The default MI (machine interface) syntax, enabled by the command line
3614 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3615 "mi1", can be enabled by specifying the option "-i=mi1".
3617 Support for the original "mi0" syntax (included in GDB 5.0) has been
3620 Fix for gdb/192: removed extraneous space when displaying frame level.
3621 Fix for gdb/672: update changelist is now output in mi list format.
3622 Fix for gdb/702: a -var-assign that updates the value now shows up
3623 in a subsequent -var-update.
3625 * New native configurations.
3627 FreeBSD/amd64 x86_64-*-freebsd*
3629 * Multi-arched targets.
3631 HP/PA HPUX11 hppa*-*-hpux*
3632 Renesas M32R/D w/simulator m32r-*-elf*
3634 * OBSOLETE configurations and files
3636 Configurations that have been declared obsolete in this release have
3637 been commented out. Unless there is activity to revive these
3638 configurations, the next release of GDB will have their sources
3639 permanently REMOVED.
3641 Z8000 simulator z8k-zilog-none or z8ksim
3642 Matsushita MN10200 w/simulator mn10200-*-*
3643 H8/500 simulator h8500-hitachi-hms or h8500hms
3644 HP/PA running BSD hppa*-*-bsd*
3645 HP/PA running OSF/1 hppa*-*-osf*
3646 HP/PA Pro target hppa*-*-pro*
3647 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3648 Sequent family i[3456]86-sequent-sysv4*
3649 i[3456]86-sequent-sysv*
3650 i[3456]86-sequent-bsd*
3651 Tsqware Sparclet sparclet-*-*
3652 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3654 * REMOVED configurations and files
3657 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3658 IBM AIX PS/2 i[3456]86-*-aix
3659 i386 running Mach 3.0 i[3456]86-*-mach3*
3660 i386 running Mach i[3456]86-*-mach*
3661 i386 running OSF/1 i[3456]86-*osf1mk*
3662 HP/Apollo 68k Family m68*-apollo*-sysv*,
3664 m68*-hp-bsd*, m68*-hp-hpux*
3665 Argonaut Risc Chip (ARC) arc-*-*
3666 Mitsubishi D30V d30v-*-*
3667 Fujitsu FR30 fr30-*-elf*
3668 OS/9000 i[34]86-*-os9k
3669 I960 with MON960 i960-*-coff
3671 * MIPS $fp behavior changed
3673 The convenience variable $fp, for the MIPS, now consistently returns
3674 the address of the current frame's base. Previously, depending on the
3675 context, $fp could refer to either $sp or the current frame's base
3676 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3677 The GNU Source-Level Debugger''.
3679 *** Changes in GDB 5.3:
3681 * GNU/Linux shared library multi-threaded performance improved.
3683 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3684 `/proc', in preference to `ptrace' for memory reads. This may result
3685 in an improvement in the start-up time of multi-threaded, shared
3686 library applications when run under GDB. One GDB user writes: ``loads
3687 shared libs like mad''.
3689 * ``gdbserver'' now supports multi-threaded applications on some targets
3691 Support for debugging multi-threaded applications which use
3692 the GNU/Linux LinuxThreads package has been added for
3693 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3694 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3696 * GDB now supports C/C++ preprocessor macros.
3698 GDB now expands preprocessor macro invocations in C/C++ expressions,
3699 and provides various commands for showing macro definitions and how
3702 The new command `macro expand EXPRESSION' expands any macro
3703 invocations in expression, and shows the result.
3705 The new command `show macro MACRO-NAME' shows the definition of the
3706 macro named MACRO-NAME, and where it was defined.
3708 Most compilers don't include information about macros in the debugging
3709 information by default. In GCC 3.1, for example, you need to compile
3710 your program with the options `-gdwarf-2 -g3'. If the macro
3711 information is present in the executable, GDB will read it.
3713 * Multi-arched targets.
3715 DEC Alpha (partial) alpha*-*-*
3716 DEC VAX (partial) vax-*-*
3718 National Semiconductor NS32000 (partial) ns32k-*-*
3719 Motorola 68000 (partial) m68k-*-*
3720 Motorola MCORE mcore-*-*
3724 Fujitsu FRV architecture added by Red Hat frv*-*-*
3727 * New native configurations
3729 Alpha NetBSD alpha*-*-netbsd*
3730 SH NetBSD sh*-*-netbsdelf*
3731 MIPS NetBSD mips*-*-netbsd*
3732 UltraSPARC NetBSD sparc64-*-netbsd*
3734 * OBSOLETE configurations and files
3736 Configurations that have been declared obsolete in this release have
3737 been commented out. Unless there is activity to revive these
3738 configurations, the next release of GDB will have their sources
3739 permanently REMOVED.
3741 Mitsubishi D30V d30v-*-*
3742 OS/9000 i[34]86-*-os9k
3743 IBM AIX PS/2 i[3456]86-*-aix
3744 Fujitsu FR30 fr30-*-elf*
3745 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3746 Argonaut Risc Chip (ARC) arc-*-*
3747 i386 running Mach 3.0 i[3456]86-*-mach3*
3748 i386 running Mach i[3456]86-*-mach*
3749 i386 running OSF/1 i[3456]86-*osf1mk*
3750 HP/Apollo 68k Family m68*-apollo*-sysv*,
3752 m68*-hp-bsd*, m68*-hp-hpux*
3753 I960 with MON960 i960-*-coff
3755 * OBSOLETE languages
3757 CHILL, a Pascal like language used by telecommunications companies.
3759 * REMOVED configurations and files
3761 AMD 29k family via UDI a29k-amd-udi, udi29k
3762 A29K VxWorks a29k-*-vxworks
3763 AMD 29000 embedded, using EBMON a29k-none-none
3764 AMD 29000 embedded with COFF a29k-none-coff
3765 AMD 29000 embedded with a.out a29k-none-aout
3767 testsuite/gdb.hp/gdb.threads-hp/ directory
3769 * New command "set max-user-call-depth <nnn>"
3771 This command allows the user to limit the call depth of user-defined
3772 commands. The default is 1024.
3774 * Changes in FreeBSD/i386 native debugging.
3776 Support for the "generate-core-file" has been added.
3778 * New commands "dump", "append", and "restore".
3780 These commands allow data to be copied from target memory
3781 to a bfd-format or binary file (dump and append), and back
3782 from a file into memory (restore).
3784 * Improved "next/step" support on multi-processor Alpha Tru64.
3786 The previous single-step mechanism could cause unpredictable problems,
3787 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3788 of a software single-step mechanism prevents this.
3790 *** Changes in GDB 5.2.1:
3798 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3799 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3800 Fix, by Joel Brobecker imported from mainline.
3802 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3803 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3804 Fix, by Fred Fish, imported from mainline.
3806 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3807 Surprisingly enough, it works now.
3808 By Michal Ludvig, imported from mainline.
3810 i386 hardware watchpoint support:
3811 avoid misses on second run for some targets.
3812 By Pierre Muller, imported from mainline.
3814 *** Changes in GDB 5.2:
3816 * New command "set trust-readonly-sections on[off]".
3818 This command is a hint that tells gdb that read-only sections
3819 really are read-only (ie. that their contents will not change).
3820 In this mode, gdb will go to the object file rather than the
3821 target to read memory from read-only sections (such as ".text").
3822 This can be a significant performance improvement on some
3823 (notably embedded) targets.
3825 * New command "generate-core-file" (or "gcore").
3827 This new gdb command allows the user to drop a core file of the child
3828 process state at any time. So far it's been implemented only for
3829 GNU/Linux and Solaris, but should be relatively easily ported to other
3830 hosts. Argument is core file name (defaults to core.<pid>).
3832 * New command line option
3834 GDB now accepts --pid or -p followed by a process id.
3836 * Change in command line behavior -- corefiles vs. process ids.
3838 There is a subtle behavior in the way in which GDB handles
3839 command line arguments. The first non-flag argument is always
3840 a program to debug, but the second non-flag argument may either
3841 be a corefile or a process id. Previously, GDB would attempt to
3842 open the second argument as a corefile, and if that failed, would
3843 issue a superfluous error message and then attempt to attach it as
3844 a process. Now, if the second argument begins with a non-digit,
3845 it will be treated as a corefile. If it begins with a digit,
3846 GDB will attempt to attach it as a process, and if no such process
3847 is found, will then attempt to open it as a corefile.
3849 * Changes in ARM configurations.
3851 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3852 configuration is fully multi-arch.
3854 * New native configurations
3856 ARM NetBSD arm*-*-netbsd*
3857 x86 OpenBSD i[3456]86-*-openbsd*
3858 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3859 Sparc64 running FreeBSD sparc64-*-freebsd*
3863 Sanyo XStormy16 xstormy16-elf
3865 * OBSOLETE configurations and files
3867 Configurations that have been declared obsolete in this release have
3868 been commented out. Unless there is activity to revive these
3869 configurations, the next release of GDB will have their sources
3870 permanently REMOVED.
3872 AMD 29k family via UDI a29k-amd-udi, udi29k
3873 A29K VxWorks a29k-*-vxworks
3874 AMD 29000 embedded, using EBMON a29k-none-none
3875 AMD 29000 embedded with COFF a29k-none-coff
3876 AMD 29000 embedded with a.out a29k-none-aout
3878 testsuite/gdb.hp/gdb.threads-hp/ directory
3880 * REMOVED configurations and files
3882 TI TMS320C80 tic80-*-*
3884 PowerPC Solaris powerpcle-*-solaris*
3885 PowerPC Windows NT powerpcle-*-cygwin32
3886 PowerPC Netware powerpc-*-netware*
3887 Harris/CXUX m88k m88*-harris-cxux*
3888 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3889 ns32k-utek-sysv* ns32k-utek-*
3890 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3891 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3892 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3893 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3894 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3896 * Changes to command line processing
3898 The new `--args' feature can be used to specify command-line arguments
3899 for the inferior from gdb's command line.
3901 * Changes to key bindings
3903 There is a new `operate-and-get-next' function bound to `C-o'.
3905 *** Changes in GDB 5.1.1
3907 Fix compile problem on DJGPP.
3909 Fix a problem with floating-point registers on the i386 being
3912 Fix to stop GDB crashing on .debug_str debug info.
3914 Numerous documentation fixes.
3916 Numerous testsuite fixes.
3918 *** Changes in GDB 5.1:
3920 * New native configurations
3922 Alpha FreeBSD alpha*-*-freebsd*
3923 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3924 MIPS GNU/Linux mips*-*-linux*
3925 MIPS SGI Irix 6.x mips*-sgi-irix6*
3926 ia64 AIX ia64-*-aix*
3927 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3931 Motorola 68HC11 and 68HC12 m68hc11-elf
3933 UltraSparc running GNU/Linux sparc64-*-linux*
3935 * OBSOLETE configurations and files
3937 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3938 Harris/CXUX m88k m88*-harris-cxux*
3939 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3940 ns32k-utek-sysv* ns32k-utek-*
3941 TI TMS320C80 tic80-*-*
3943 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3944 PowerPC Solaris powerpcle-*-solaris*
3945 PowerPC Windows NT powerpcle-*-cygwin32
3946 PowerPC Netware powerpc-*-netware*
3947 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3948 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3949 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3950 Apple Macintosh (MPW) host N/A
3952 stuff.c (Program to stuff files into a specially prepared space in kdb)
3953 kdb-start.c (Main loop for the standalone kernel debugger)
3955 Configurations that have been declared obsolete in this release have
3956 been commented out. Unless there is activity to revive these
3957 configurations, the next release of GDB will have their sources
3958 permanently REMOVED.
3960 * REMOVED configurations and files
3962 Altos 3068 m68*-altos-*
3963 Convex c1-*-*, c2-*-*
3965 ARM RISCix arm-*-* (as host)
3969 * GDB has been converted to ISO C.
3971 GDB's source code has been converted to ISO C. In particular, the
3972 sources are fully protoized, and rely on standard headers being
3977 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3979 * The MI enabled by default.
3981 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3982 revised and enabled by default. Packages which use GDB as a debugging
3983 engine behind a UI or another front end are encouraged to switch to
3984 using the GDB/MI interface, instead of the old annotations interface
3985 which is now deprecated.
3987 * Support for debugging Pascal programs.
3989 GDB now includes support for debugging Pascal programs. The following
3990 main features are supported:
3992 - Pascal-specific data types such as sets;
3994 - automatic recognition of Pascal sources based on file-name
3997 - Pascal-style display of data types, variables, and functions;
3999 - a Pascal expression parser.
4001 However, some important features are not yet supported.
4003 - Pascal string operations are not supported at all;
4005 - there are some problems with boolean types;
4007 - Pascal type hexadecimal constants are not supported
4008 because they conflict with the internal variables format;
4010 - support for Pascal objects and classes is not full yet;
4012 - unlike Pascal, GDB is case-sensitive for symbol names.
4014 * Changes in completion.
4016 Commands such as `shell', `run' and `set args', which pass arguments
4017 to inferior programs, now complete on file names, similar to what
4018 users expect at the shell prompt.
4020 Commands which accept locations, such as `disassemble', `print',
4021 `breakpoint', `until', etc. now complete on filenames as well as
4022 program symbols. Thus, if you type "break foob TAB", and the source
4023 files linked into the programs include `foobar.c', that file name will
4024 be one of the candidates for completion. However, file names are not
4025 considered for completion after you typed a colon that delimits a file
4026 name from a name of a function in that file, as in "break foo.c:bar".
4028 `set demangle-style' completes on available demangling styles.
4030 * New platform-independent commands:
4032 It is now possible to define a post-hook for a command as well as a
4033 hook that runs before the command. For more details, see the
4034 documentation of `hookpost' in the GDB manual.
4036 * Changes in GNU/Linux native debugging.
4038 Support for debugging multi-threaded programs has been completely
4039 revised for all platforms except m68k and sparc. You can now debug as
4040 many threads as your system allows you to have.
4042 Attach/detach is supported for multi-threaded programs.
4044 Support for SSE registers was added for x86. This doesn't work for
4045 multi-threaded programs though.
4047 * Changes in MIPS configurations.
4049 Multi-arch support is enabled for all MIPS configurations.
4051 GDB can now be built as native debugger on SGI Irix 6.x systems for
4052 debugging n32 executables. (Debugging 64-bit executables is not yet
4055 * Unified support for hardware watchpoints in all x86 configurations.
4057 Most (if not all) native x86 configurations support hardware-assisted
4058 breakpoints and watchpoints in a unified manner. This support
4059 implements debug register sharing between watchpoints, which allows to
4060 put a virtually infinite number of watchpoints on the same address,
4061 and also supports watching regions up to 16 bytes with several debug
4064 The new maintenance command `maintenance show-debug-regs' toggles
4065 debugging print-outs in functions that insert, remove, and test
4066 watchpoints and hardware breakpoints.
4068 * Changes in the DJGPP native configuration.
4070 New command ``info dos sysinfo'' displays assorted information about
4071 the CPU, OS, memory, and DPMI server.
4073 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4074 display information about segment descriptors stored in GDT, LDT, and
4077 New commands ``info dos pde'' and ``info dos pte'' display entries
4078 from Page Directory and Page Tables (for now works with CWSDPMI only).
4079 New command ``info dos address-pte'' displays the Page Table entry for
4080 a given linear address.
4082 GDB can now pass command lines longer than 126 characters to the
4083 program being debugged (requires an update to the libdbg.a library
4084 which is part of the DJGPP development kit).
4086 DWARF2 debug info is now supported.
4088 It is now possible to `step' and `next' through calls to `longjmp'.
4090 * Changes in documentation.
4092 All GDB documentation was converted to GFDL, the GNU Free
4093 Documentation License.
4095 Tracepoints-related commands are now fully documented in the GDB
4098 TUI, the Text-mode User Interface, is now documented in the manual.
4100 Tracepoints-related commands are now fully documented in the GDB
4103 The "GDB Internals" manual now has an index. It also includes
4104 documentation of `ui_out' functions, GDB coding standards, x86
4105 hardware watchpoints, and memory region attributes.
4107 * GDB's version number moved to ``version.in''
4109 The Makefile variable VERSION has been replaced by the file
4110 ``version.in''. People creating GDB distributions should update the
4111 contents of this file.
4115 GUD support is now a standard part of the EMACS distribution.
4117 *** Changes in GDB 5.0:
4119 * Improved support for debugging FP programs on x86 targets
4121 Unified and much-improved support for debugging floating-point
4122 programs on all x86 targets. In particular, ``info float'' now
4123 displays the FP registers in the same format on all x86 targets, with
4124 greater level of detail.
4126 * Improvements and bugfixes in hardware-assisted watchpoints
4128 It is now possible to watch array elements, struct members, and
4129 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4130 on x86 targets no longer erroneously trigger when the address is
4133 * Improvements in the native DJGPP version of GDB
4135 The distribution now includes all the scripts and auxiliary files
4136 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4137 machines ``out of the box''.
4139 The DJGPP version can now debug programs that use signals. It is
4140 possible to catch signals that happened in the debuggee, deliver
4141 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4142 would kill the program being debugged.) Programs that hook hardware
4143 interrupts (keyboard, timer, etc.) can also be debugged.
4145 It is now possible to debug DJGPP programs that redirect their
4146 standard handles or switch them to raw (as opposed to cooked) mode, or
4147 even close them. The command ``run < foo > bar'' works as expected,
4148 and ``info terminal'' reports useful information about the debuggee's
4149 terminal, including raw/cooked mode, redirection, etc.
4151 The DJGPP version now uses termios functions for console I/O, which
4152 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4155 DOS-style file names with drive letters are now fully supported by
4158 It is now possible to debug DJGPP programs that switch their working
4159 directory. It is also possible to rerun the debuggee any number of
4160 times without restarting GDB; thus, you can use the same setup,
4161 breakpoints, etc. for many debugging sessions.
4163 * New native configurations
4165 ARM GNU/Linux arm*-*-linux*
4166 PowerPC GNU/Linux powerpc-*-linux*
4170 Motorola MCore mcore-*-*
4171 x86 VxWorks i[3456]86-*-vxworks*
4172 PowerPC VxWorks powerpc-*-vxworks*
4173 TI TMS320C80 tic80-*-*
4175 * OBSOLETE configurations
4177 Altos 3068 m68*-altos-*
4178 Convex c1-*-*, c2-*-*
4180 ARM RISCix arm-*-* (as host)
4183 Configurations that have been declared obsolete will be commented out,
4184 but the code will be left in place. If there is no activity to revive
4185 these configurations before the next release of GDB, the sources will
4186 be permanently REMOVED.
4188 * Gould support removed
4190 Support for the Gould PowerNode and NP1 has been removed.
4192 * New features for SVR4
4194 On SVR4 native platforms (such as Solaris), if you attach to a process
4195 without first loading a symbol file, GDB will now attempt to locate and
4196 load symbols from the running process's executable file.
4198 * Many C++ enhancements
4200 C++ support has been greatly improved. Overload resolution now works properly
4201 in almost all cases. RTTI support is on the way.
4203 * Remote targets can connect to a sub-program
4205 A popen(3) style serial-device has been added. This device starts a
4206 sub-process (such as a stand-alone simulator) and then communicates
4207 with that. The sub-program to run is specified using the syntax
4208 ``|<program> <args>'' vis:
4210 (gdb) set remotedebug 1
4211 (gdb) target extended-remote |mn10300-elf-sim program-args
4213 * MIPS 64 remote protocol
4215 A long standing bug in the mips64 remote protocol where by GDB
4216 expected certain 32 bit registers (ex SR) to be transfered as 32
4217 instead of 64 bits has been fixed.
4219 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4220 added to provide backward compatibility with older versions of GDB.
4222 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4224 The command ``set remotebinarydownload'' command has been replaced by
4225 ``set remote X-packet''. Other commands in ``set remote'' family
4226 include ``set remote P-packet''.
4228 * Breakpoint commands accept ranges.
4230 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4231 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4232 ``tracepoint passcount'' also accepts a range of tracepoints.
4234 * ``apropos'' command added.
4236 The ``apropos'' command searches through command names and
4237 documentation strings, printing out matches, making it much easier to
4238 try to find a command that does what you are looking for.
4242 A new machine oriented interface (MI) has been added to GDB. This
4243 interface is designed for debug environments running GDB as a separate
4244 process. This is part of the long term libGDB project. See the
4245 "GDB/MI" chapter of the GDB manual for further information. It can be
4246 enabled by configuring with:
4248 .../configure --enable-gdbmi
4250 *** Changes in GDB-4.18:
4252 * New native configurations
4254 HP-UX 10.20 hppa*-*-hpux10.20
4255 HP-UX 11.x hppa*-*-hpux11.0*
4256 M68K GNU/Linux m68*-*-linux*
4260 Fujitsu FR30 fr30-*-elf*
4261 Intel StrongARM strongarm-*-*
4262 Mitsubishi D30V d30v-*-*
4264 * OBSOLETE configurations
4266 Gould PowerNode, NP1 np1-*-*, pn-*-*
4268 Configurations that have been declared obsolete will be commented out,
4269 but the code will be left in place. If there is no activity to revive
4270 these configurations before the next release of GDB, the sources will
4271 be permanently REMOVED.
4275 As a compatibility experiment, GDB's source files buildsym.h and
4276 buildsym.c have been converted to pure standard C, no longer
4277 containing any K&R compatibility code. We believe that all systems in
4278 use today either come with a standard C compiler, or have a GCC port
4279 available. If this is not true, please report the affected
4280 configuration to bug-gdb@gnu.org immediately. See the README file for
4281 information about getting a standard C compiler if you don't have one
4286 GDB now uses readline 2.2.
4288 * set extension-language
4290 You can now control the mapping between filename extensions and source
4291 languages by using the `set extension-language' command. For instance,
4292 you can ask GDB to treat .c files as C++ by saying
4293 set extension-language .c c++
4294 The command `info extensions' lists all of the recognized extensions
4295 and their associated languages.
4297 * Setting processor type for PowerPC and RS/6000
4299 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4300 you can use the `set processor' command to specify what variant of the
4301 PowerPC family you are debugging. The command
4305 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4306 following PowerPC and RS6000 variants:
4308 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4309 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4311 403GC IBM PowerPC 403GC
4312 505 Motorola PowerPC 505
4313 860 Motorola PowerPC 860 or 850
4314 601 Motorola PowerPC 601
4315 602 Motorola PowerPC 602
4316 603 Motorola/IBM PowerPC 603 or 603e
4317 604 Motorola PowerPC 604 or 604e
4318 750 Motorola/IBM PowerPC 750 or 750
4320 At the moment, this command just tells GDB what to name the
4321 special-purpose processor registers. Since almost all the affected
4322 registers are inaccessible to user-level programs, this command is
4323 only useful for remote debugging in its present form.
4327 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4328 more extensive support for HP-UX. Added features include shared
4329 library support, kernel threads and hardware watchpoints for 11.00,
4330 support for HP's ANSI C and C++ compilers, and a compatibility mode
4331 for xdb and dbx commands.
4335 HP's donation includes the new concept of catchpoints, which is a
4336 generalization of the old catch command. On HP-UX, it is now possible
4337 to catch exec, fork, and vfork, as well as library loading.
4339 This means that the existing catch command has changed; its first
4340 argument now specifies the type of catch to be set up. See the
4341 output of "help catch" for a list of catchpoint types.
4343 * Debugging across forks
4345 On HP-UX, you can choose which process to debug when a fork() happens
4350 HP has donated a curses-based terminal user interface (TUI). To get
4351 it, build with --enable-tui. Although this can be enabled for any
4352 configuration, at present it only works for native HP debugging.
4354 * GDB remote protocol additions
4356 A new protocol packet 'X' that writes binary data is now available.
4357 Default behavior is to try 'X', then drop back to 'M' if the stub
4358 fails to respond. The settable variable `remotebinarydownload'
4359 allows explicit control over the use of 'X'.
4361 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4362 full 64-bit address. The command
4364 set remoteaddresssize 32
4366 can be used to revert to the old behaviour. For existing remote stubs
4367 the change should not be noticed, as the additional address information
4370 In order to assist in debugging stubs, you may use the maintenance
4371 command `packet' to send any text string to the stub. For instance,
4373 maint packet heythere
4375 sends the packet "$heythere#<checksum>". Note that it is very easy to
4376 disrupt a debugging session by sending the wrong packet at the wrong
4379 The compare-sections command allows you to compare section data on the
4380 target to what is in the executable file without uploading or
4381 downloading, by comparing CRC checksums.
4383 * Tracing can collect general expressions
4385 You may now collect general expressions at tracepoints. This requires
4386 further additions to the target-side stub; see tracepoint.c and
4387 doc/agentexpr.texi for further details.
4389 * mask-address variable for Mips
4391 For Mips targets, you may control the zeroing of the upper 32 bits of
4392 a 64-bit address by entering `set mask-address on'. This is mainly
4393 of interest to users of embedded R4xxx and R5xxx processors.
4395 * Higher serial baud rates
4397 GDB's serial code now allows you to specify baud rates 57600, 115200,
4398 230400, and 460800 baud. (Note that your host system may not be able
4399 to achieve all of these rates.)
4403 The i960 configuration now includes an initial implementation of a
4404 builtin simulator, contributed by Jim Wilson.
4407 *** Changes in GDB-4.17:
4409 * New native configurations
4411 Alpha GNU/Linux alpha*-*-linux*
4412 Unixware 2.x i[3456]86-unixware2*
4413 Irix 6.x mips*-sgi-irix6*
4414 PowerPC GNU/Linux powerpc-*-linux*
4415 PowerPC Solaris powerpcle-*-solaris*
4416 Sparc GNU/Linux sparc-*-linux*
4417 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4421 Argonaut Risc Chip (ARC) arc-*-*
4422 Hitachi H8/300S h8300*-*-*
4423 Matsushita MN10200 w/simulator mn10200-*-*
4424 Matsushita MN10300 w/simulator mn10300-*-*
4425 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4426 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4427 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4428 Mitsubishi D10V w/simulator d10v-*-*
4429 Mitsubishi M32R/D w/simulator m32r-*-elf*
4430 Tsqware Sparclet sparclet-*-*
4431 NEC V850 w/simulator v850-*-*
4433 * New debugging protocols
4435 ARM with RDI protocol arm*-*-*
4436 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4437 DDB and LSI variants of PMON protocol mips*-*-*
4438 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4439 PowerPC with SDS protocol powerpc{,le}-*-eabi
4440 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4444 All configurations can now understand and use the DWARF 2 debugging
4445 format. The choice is automatic, if the symbol file contains DWARF 2
4450 GDB now includes basic Java language support. This support is
4451 only useful with Java compilers that produce native machine code.
4453 * solib-absolute-prefix and solib-search-path
4455 For SunOS and SVR4 shared libraries, you may now set the prefix for
4456 loading absolute shared library symbol files, and the search path for
4457 locating non-absolute shared library symbol files.
4459 * Live range splitting
4461 GDB can now effectively debug code for which GCC has performed live
4462 range splitting as part of its optimization. See gdb/doc/LRS for
4463 more details on the expected format of the stabs information.
4467 GDB's support for the GNU Hurd, including thread debugging, has been
4468 updated to work with current versions of the Hurd.
4472 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4473 instruction set. ARM GDB automatically detects when Thumb
4474 instructions are in use, and adjusts disassembly and backtracing
4479 GDB's MIPS target configurations now handle the MIP16 16-bit
4484 GDB now includes support for overlays; if an executable has been
4485 linked such that multiple sections are based at the same address, GDB
4486 will decide which section to use for symbolic info. You can choose to
4487 control the decision manually, using overlay commands, or implement
4488 additional target-side support and use "overlay load-target" to bring
4489 in the overlay mapping. Do "help overlay" for more detail.
4493 The command "info symbol <address>" displays information about
4494 the symbol at the specified address.
4498 The standard remote protocol now includes an extension that allows
4499 asynchronous collection and display of trace data. This requires
4500 extensive support in the target-side debugging stub. Tracing mode
4501 includes a new interaction mode in GDB and new commands: see the
4502 file tracepoint.c for more details.
4506 Configurations for embedded MIPS now include a simulator contributed
4507 by Cygnus Solutions. The simulator supports the instruction sets
4508 of most MIPS variants.
4512 Sparc configurations may now include the ERC32 simulator contributed
4513 by the European Space Agency. The simulator is not built into
4514 Sparc targets by default; configure with --enable-sim to include it.
4518 For target configurations that may include multiple variants of a
4519 basic architecture (such as MIPS and SH), you may now set the
4520 architecture explicitly. "set arch" sets, "info arch" lists
4521 the possible architectures.
4523 *** Changes in GDB-4.16:
4525 * New native configurations
4527 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4528 M68K NetBSD m68k-*-netbsd*
4529 PowerPC AIX 4.x powerpc-*-aix*
4530 PowerPC MacOS powerpc-*-macos*
4531 PowerPC Windows NT powerpcle-*-cygwin32
4532 RS/6000 AIX 4.x rs6000-*-aix4*
4536 ARM with RDP protocol arm-*-*
4537 I960 with MON960 i960-*-coff
4538 MIPS VxWorks mips*-*-vxworks*
4539 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4540 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4542 Matra Sparclet sparclet-*-*
4546 The powerpc-eabi configuration now includes the PSIM simulator,
4547 contributed by Andrew Cagney, with assistance from Mike Meissner.
4548 PSIM is a very elaborate model of the PowerPC, including not only
4549 basic instruction set execution, but also details of execution unit
4550 performance and I/O hardware. See sim/ppc/README for more details.
4554 GDB now works with Solaris 2.5.
4556 * Windows 95/NT native
4558 GDB will now work as a native debugger on Windows 95 and Windows NT.
4559 To build it from source, you must use the "gnu-win32" environment,
4560 which uses a DLL to emulate enough of Unix to run the GNU tools.
4561 Further information, binaries, and sources are available at
4562 ftp.cygnus.com, under pub/gnu-win32.
4564 * dont-repeat command
4566 If a user-defined command includes the command `dont-repeat', then the
4567 command will not be repeated if the user just types return. This is
4568 useful if the command is time-consuming to run, so that accidental
4569 extra keystrokes don't run the same command many times.
4571 * Send break instead of ^C
4573 The standard remote protocol now includes an option to send a break
4574 rather than a ^C to the target in order to interrupt it. By default,
4575 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4577 * Remote protocol timeout
4579 The standard remote protocol includes a new variable `remotetimeout'
4580 that allows you to set the number of seconds before GDB gives up trying
4581 to read from the target. The default value is 2.
4583 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4585 By default GDB will automatically keep track of objects as they are
4586 loaded and unloaded by the dynamic linker. By using the command `set
4587 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4588 when shared library events occur, thus allowing you to set breakpoints
4589 in shared libraries which are explicitly loaded by the inferior.
4591 Note this feature does not work on hpux8. On hpux9 you must link
4592 /usr/lib/end.o into your program. This feature should work
4593 automatically on hpux10.
4595 * Irix 5.x hardware watchpoint support
4597 Irix 5 configurations now support the use of hardware watchpoints.
4599 * Mips protocol "SYN garbage limit"
4601 When debugging a Mips target using the `target mips' protocol, you
4602 may set the number of characters that GDB will ignore by setting
4603 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4604 every character. The default value is 1050.
4606 * Recording and replaying remote debug sessions
4608 If you set `remotelogfile' to the name of a file, gdb will write to it
4609 a recording of a remote debug session. This recording may then be
4610 replayed back to gdb using "gdbreplay". See gdbserver/README for
4611 details. This is useful when you have a problem with GDB while doing
4612 remote debugging; you can make a recording of the session and send it
4613 to someone else, who can then recreate the problem.
4615 * Speedups for remote debugging
4617 GDB includes speedups for downloading and stepping MIPS systems using
4618 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4619 and more efficient S-record downloading.
4621 * Memory use reductions and statistics collection
4623 GDB now uses less memory and reports statistics about memory usage.
4624 Try the `maint print statistics' command, for example.
4626 *** Changes in GDB-4.15:
4628 * Psymtabs for XCOFF
4630 The symbol reader for AIX GDB now uses partial symbol tables. This
4631 can greatly improve startup time, especially for large executables.
4633 * Remote targets use caching
4635 Remote targets now use a data cache to speed up communication with the
4636 remote side. The data cache could lead to incorrect results because
4637 it doesn't know about volatile variables, thus making it impossible to
4638 debug targets which use memory mapped I/O devices. `set remotecache
4639 off' turns the the data cache off.
4641 * Remote targets may have threads
4643 The standard remote protocol now includes support for multiple threads
4644 in the target system, using new protocol commands 'H' and 'T'. See
4645 gdb/remote.c for details.
4649 If GDB is configured with `--enable-netrom', then it will include
4650 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4651 acts as though it is a bank of ROM on the target board, but you can
4652 write into it over the network. GDB's support consists only of
4653 support for fast loading into the emulated ROM; to debug, you must use
4654 another protocol, such as standard remote protocol. The usual
4655 sequence is something like
4657 target nrom <netrom-hostname>
4659 target remote <netrom-hostname>:1235
4663 GDB now includes support for the Apple Macintosh, as a host only. It
4664 may be run as either an MPW tool or as a standalone application, and
4665 it can debug through the serial port. All the usual GDB commands are
4666 available, but to the target command, you must supply "serial" as the
4667 device type instead of "/dev/ttyXX". See mpw-README in the main
4668 directory for more information on how to build. The MPW configuration
4669 scripts */mpw-config.in support only a few targets, and only the
4670 mips-idt-ecoff target has been tested.
4674 GDB configuration now uses autoconf. This is not user-visible,
4675 but does simplify configuration and building.
4679 GDB now supports hpux10.
4681 *** Changes in GDB-4.14:
4683 * New native configurations
4685 x86 FreeBSD i[345]86-*-freebsd
4686 x86 NetBSD i[345]86-*-netbsd
4687 NS32k NetBSD ns32k-*-netbsd
4688 Sparc NetBSD sparc-*-netbsd
4692 A29K VxWorks a29k-*-vxworks
4693 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4694 CPU32 EST-300 emulator m68*-*-est*
4695 PowerPC ELF powerpc-*-elf
4698 * Alpha OSF/1 support for procfs
4700 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4701 possible to attach to running processes. As the mounting of the /proc
4702 filesystem is optional on the Alpha, GDB automatically determines
4703 the availability of /proc during startup. This can lead to problems
4704 if /proc is unmounted after GDB has been started.
4706 * Arguments to user-defined commands
4708 User commands may accept up to 10 arguments separated by whitespace.
4709 Arguments are accessed within the user command via $arg0..$arg9. A
4712 print $arg0 + $arg1 + $arg2
4714 To execute the command use:
4717 Defines the command "adder" which prints the sum of its three arguments.
4718 Note the arguments are text substitutions, so they may reference variables,
4719 use complex expressions, or even perform inferior function calls.
4721 * New `if' and `while' commands
4723 This makes it possible to write more sophisticated user-defined
4724 commands. Both commands take a single argument, which is the
4725 expression to evaluate, and must be followed by the commands to
4726 execute, one per line, if the expression is nonzero, the list being
4727 terminated by the word `end'. The `if' command list may include an
4728 `else' word, which causes the following commands to be executed only
4729 if the expression is zero.
4731 * Fortran source language mode
4733 GDB now includes partial support for Fortran 77. It will recognize
4734 Fortran programs and can evaluate a subset of Fortran expressions, but
4735 variables and functions may not be handled correctly. GDB will work
4736 with G77, but does not yet know much about symbols emitted by other
4739 * Better HPUX support
4741 Most debugging facilities now work on dynamic executables for HPPAs
4742 running hpux9 or later. You can attach to running dynamically linked
4743 processes, but by default the dynamic libraries will be read-only, so
4744 for instance you won't be able to put breakpoints in them. To change
4745 that behavior do the following before running the program:
4751 This will cause the libraries to be mapped private and read-write.
4752 To revert to the normal behavior, do this:
4758 You cannot set breakpoints or examine data in the library until after
4759 the library is loaded if the function/data symbols do not have
4762 GDB can now also read debug symbols produced by the HP C compiler on
4763 HPPAs (sorry, no C++, Fortran or 68k support).
4765 * Target byte order now dynamically selectable
4767 You can choose which byte order to use with a target system, via the
4768 commands "set endian big" and "set endian little", and you can see the
4769 current setting by using "show endian". You can also give the command
4770 "set endian auto", in which case GDB will use the byte order
4771 associated with the executable. Currently, only embedded MIPS
4772 configurations support dynamic selection of target byte order.
4774 * New DOS host serial code
4776 This version uses DPMI interrupts to handle buffered I/O, so you
4777 no longer need to run asynctsr when debugging boards connected to
4780 *** Changes in GDB-4.13:
4782 * New "complete" command
4784 This lists all the possible completions for the rest of the line, if it
4785 were to be given as a command itself. This is intended for use by emacs.
4787 * Trailing space optional in prompt
4789 "set prompt" no longer adds a space for you after the prompt you set. This
4790 allows you to set a prompt which ends in a space or one that does not.
4792 * Breakpoint hit counts
4794 "info break" now displays a count of the number of times the breakpoint
4795 has been hit. This is especially useful in conjunction with "ignore"; you
4796 can ignore a large number of breakpoint hits, look at the breakpoint info
4797 to see how many times the breakpoint was hit, then run again, ignoring one
4798 less than that number, and this will get you quickly to the last hit of
4801 * Ability to stop printing at NULL character
4803 "set print null-stop" will cause GDB to stop printing the characters of
4804 an array when the first NULL is encountered. This is useful when large
4805 arrays actually contain only short strings.
4807 * Shared library breakpoints
4809 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4810 breakpoints in shared libraries before the executable is run.
4812 * Hardware watchpoints
4814 There is a new hardware breakpoint for the watch command for sparclite
4815 targets. See gdb/sparclite/hw_breakpoint.note.
4817 Hardware watchpoints are also now supported under GNU/Linux.
4821 Annotations have been added. These are for use with graphical interfaces,
4822 and are still experimental. Currently only gdba.el uses these.
4824 * Improved Irix 5 support
4826 GDB now works properly with Irix 5.2.
4828 * Improved HPPA support
4830 GDB now works properly with the latest GCC and GAS.
4832 * New native configurations
4834 Sequent PTX4 i[34]86-sequent-ptx4
4835 HPPA running OSF/1 hppa*-*-osf*
4836 Atari TT running SVR4 m68*-*-sysv4*
4837 RS/6000 LynxOS rs6000-*-lynxos*
4841 OS/9000 i[34]86-*-os9k
4842 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4845 * Hitachi SH7000 and E7000-PC ICE support
4847 There is now support for communicating with the Hitachi E7000-PC ICE.
4848 This is available automatically when GDB is configured for the SH.
4852 As usual, a variety of small fixes and improvements, both generic
4853 and configuration-specific. See the ChangeLog for more detail.
4855 *** Changes in GDB-4.12:
4857 * Irix 5 is now supported
4861 GDB-4.12 on the HPPA has a number of changes which make it unable
4862 to debug the output from the currently released versions of GCC and
4863 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4864 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4865 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4868 *** Changes in GDB-4.11:
4870 * User visible changes:
4874 The "set remotedebug" option is now consistent between the mips remote
4875 target, remote targets using the gdb-specific protocol, UDI (AMD's
4876 debug protocol for the 29k) and the 88k bug monitor. It is now an
4877 integer specifying a debug level (normally 0 or 1, but 2 means more
4878 debugging info for the mips target).
4880 * DEC Alpha native support
4882 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4883 debug info, but GDB works fairly well with the DEC compiler and should
4884 work with a future GCC release. See the README file for a few
4885 Alpha-specific notes.
4887 * Preliminary thread implementation
4889 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4891 * LynxOS native and target support for 386
4893 This release has been hosted on LynxOS 2.2, and also can be configured
4894 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4897 * Improvements in C++ mangling/demangling.
4899 This release has much better g++ debugging, specifically in name
4900 mangling/demangling, virtual function calls, print virtual table,
4901 call methods, ...etc.
4903 *** Changes in GDB-4.10:
4905 * User visible changes:
4907 Remote debugging using the GDB-specific (`target remote') protocol now
4908 supports the `load' command. This is only useful if you have some
4909 other way of getting the stub to the target system, and you can put it
4910 somewhere in memory where it won't get clobbered by the download.
4912 Filename completion now works.
4914 When run under emacs mode, the "info line" command now causes the
4915 arrow to point to the line specified. Also, "info line" prints
4916 addresses in symbolic form (as well as hex).
4918 All vxworks based targets now support a user settable option, called
4919 vxworks-timeout. This option represents the number of seconds gdb
4920 should wait for responses to rpc's. You might want to use this if
4921 your vxworks target is, perhaps, a slow software simulator or happens
4922 to be on the far side of a thin network line.
4926 This release contains support for using a DEC alpha as a GDB host for
4927 cross debugging. Native alpha debugging is not supported yet.
4930 *** Changes in GDB-4.9:
4934 This is the first GDB release which is accompanied by a matching testsuite.
4935 The testsuite requires installation of dejagnu, which should be available
4936 via ftp from most sites that carry GNU software.
4940 'Cfront' style demangling has had its name changed to 'ARM' style, to
4941 emphasize that it was written from the specifications in the C++ Annotated
4942 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4943 disclaimers, it still generated too much confusion with users attempting to
4944 use gdb with AT&T cfront.
4948 GDB now uses a standard remote interface to a simulator library.
4949 So far, the library contains simulators for the Zilog Z8001/2, the
4950 Hitachi H8/300, H8/500 and Super-H.
4952 * New targets supported
4954 H8/300 simulator h8300-hitachi-hms or h8300hms
4955 H8/500 simulator h8500-hitachi-hms or h8500hms
4956 SH simulator sh-hitachi-hms or sh
4957 Z8000 simulator z8k-zilog-none or z8ksim
4958 IDT MIPS board over serial line mips-idt-ecoff
4960 Cross-debugging to GO32 targets is supported. It requires a custom
4961 version of the i386-stub.c module which is integrated with the
4962 GO32 memory extender.
4964 * New remote protocols
4966 MIPS remote debugging protocol.
4968 * New source languages supported
4970 This version includes preliminary support for Chill, a Pascal like language
4971 used by telecommunications companies. Chill support is also being integrated
4972 into the GNU compiler, but we don't know when it will be publically available.
4975 *** Changes in GDB-4.8:
4977 * HP Precision Architecture supported
4979 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4980 version of this support was available as a set of patches from the
4981 University of Utah. GDB does not support debugging of programs
4982 compiled with the HP compiler, because HP will not document their file
4983 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4984 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4986 Many problems in the preliminary version have been fixed.
4988 * Faster and better demangling
4990 We have improved template demangling and fixed numerous bugs in the GNU style
4991 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4992 character types (wchar_t) are now supported. Demangling of each symbol is now
4993 only done once, and is cached when the symbol table for a file is read in.
4994 This results in a small increase in memory usage for C programs, a moderate
4995 increase in memory usage for C++ programs, and a fantastic speedup in
4998 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4999 from the specifications in the Annotated Reference Manual, which AT&T's
5000 compiler does not actually implement.
5002 * G++ multiple inheritance compiler problem
5004 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5005 inheritance lattices was reworked to properly discover ambiguities. We
5006 recently found an example which causes this new algorithm to fail in a
5007 very subtle way, producing bad debug information for those classes.
5008 The file 'gcc.patch' (in this directory) can be applied to gcc to
5009 circumvent the problem. A future GCC release will contain a complete
5012 The previous G++ debug info problem (mentioned below for the gdb-4.7
5013 release) is fixed in gcc version 2.3.2.
5015 * Improved configure script
5017 The `configure' script will now attempt to guess your system type if
5018 you don't supply a host system type. The old scheme of supplying a
5019 host system triplet is preferable over using this. All the magic is
5020 done in the new `config.guess' script. Examine it for details.
5022 We have also brought our configure script much more in line with the FSF's
5023 version. It now supports the --with-xxx options. In particular,
5024 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5025 The resulting GDB will not be able to read arbitrary object file formats --
5026 only the format ``expected'' to be used on the configured target system.
5027 We hope to make this the default in a future release.
5029 * Documentation improvements
5031 There's new internal documentation on how to modify GDB, and how to
5032 produce clean changes to the code. We implore people to read it
5033 before submitting changes.
5035 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5036 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5037 `info' files are also provided. To build `info' files from scratch,
5038 you will need the latest `makeinfo' release, which will be available in
5039 a future texinfo-X.Y release.
5041 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5042 We're not sure exactly which versions have this problem, but it has
5043 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5044 or better. If that isn't possible, there is a patch in
5045 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5046 around this problem.
5050 GDB now supports array constants that can be used in expressions typed in by
5051 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5052 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5055 The new directory `gdb/sparclite' contains a program that demonstrates
5056 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5058 * New native hosts supported
5060 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5061 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5063 * New targets supported
5065 AMD 29k family via UDI a29k-amd-udi or udi29k
5067 * New file formats supported
5069 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5070 HPUX core files, and SCO 3.2v2 core files.
5074 Attaching to processes now works again; thanks for the many bug reports.
5076 We have also stomped on a bunch of core dumps caused by
5077 printf_filtered("%s") problems.
5079 We eliminated a copyright problem on the rpc and ptrace header files
5080 for VxWorks, which was discovered at the last minute during the 4.7
5081 release. You should now be able to build a VxWorks GDB.
5083 You can now interrupt gdb while an attached process is running. This
5084 will cause the attached process to stop, and give control back to GDB.
5086 We fixed problems caused by using too many file descriptors
5087 for reading symbols from object files and libraries. This was
5088 especially a problem for programs that used many (~100) shared
5091 The `step' command now only enters a subroutine if there is line number
5092 information for the subroutine. Otherwise it acts like the `next'
5093 command. Previously, `step' would enter subroutines if there was
5094 any debugging information about the routine. This avoids problems
5095 when using `cc -g1' on MIPS machines.
5097 * Internal improvements
5099 GDB's internal interfaces have been improved to make it easier to support
5100 debugging of multiple languages in the future.
5102 GDB now uses a common structure for symbol information internally.
5103 Minimal symbols (derived from linkage symbols in object files), partial
5104 symbols (from a quick scan of debug information), and full symbols
5105 contain a common subset of information, making it easier to write
5106 shared code that handles any of them.
5108 * New command line options
5110 We now accept --silent as an alias for --quiet.
5114 The memory-mapped-malloc library is now licensed under the GNU Library
5115 General Public License.
5117 *** Changes in GDB-4.7:
5119 * Host/native/target split
5121 GDB has had some major internal surgery to untangle the support for
5122 hosts and remote targets. Now, when you configure GDB for a remote
5123 target, it will no longer load in all of the support for debugging
5124 local programs on the host. When fully completed and tested, this will
5125 ensure that arbitrary host/target combinations are possible.
5127 The primary conceptual shift is to separate the non-portable code in
5128 GDB into three categories. Host specific code is required any time GDB
5129 is compiled on that host, regardless of the target. Target specific
5130 code relates to the peculiarities of the target, but can be compiled on
5131 any host. Native specific code is everything else: it can only be
5132 built when the host and target are the same system. Child process
5133 handling and core file support are two common `native' examples.
5135 GDB's use of /proc for controlling Unix child processes is now cleaner.
5136 It has been split out into a single module under the `target_ops' vector,
5137 plus two native-dependent functions for each system that uses /proc.
5139 * New hosts supported
5141 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5142 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5143 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5145 * New targets supported
5147 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5148 68030 and CPU32 m68030-*-*, m68332-*-*
5150 * New native hosts supported
5152 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5153 (386bsd is not well tested yet)
5154 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5156 * New file formats supported
5158 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5159 supports reading of `a.out.adobe' object files, which are an a.out
5160 format extended with minimal information about multiple sections.
5164 `show copying' is the same as the old `info copying'.
5165 `show warranty' is the same as `info warrantee'.
5166 These were renamed for consistency. The old commands continue to work.
5168 `info handle' is a new alias for `info signals'.
5170 You can now define pre-command hooks, which attach arbitrary command
5171 scripts to any command. The commands in the hook will be executed
5172 prior to the user's command. You can also create a hook which will be
5173 executed whenever the program stops. See gdb.texinfo.
5177 We now deal with Cfront style name mangling, and can even extract type
5178 info from mangled symbols. GDB can automatically figure out which
5179 symbol mangling style your C++ compiler uses.
5181 Calling of methods and virtual functions has been improved as well.
5185 The crash that occured when debugging Sun Ansi-C compiled binaries is
5186 fixed. This was due to mishandling of the extra N_SO stabs output
5189 We also finally got Ultrix 4.2 running in house, and fixed core file
5190 support, with help from a dozen people on the net.
5192 John M. Farrell discovered that the reason that single-stepping was so
5193 slow on all of the Mips based platforms (primarily SGI and DEC) was
5194 that we were trying to demangle and lookup a symbol used for internal
5195 purposes on every instruction that was being stepped through. Changing
5196 the name of that symbol so that it couldn't be mistaken for a C++
5197 mangled symbol sped things up a great deal.
5199 Rich Pixley sped up symbol lookups in general by getting much smarter
5200 about when C++ symbol mangling is necessary. This should make symbol
5201 completion (TAB on the command line) much faster. It's not as fast as
5202 we'd like, but it's significantly faster than gdb-4.6.
5206 A new user controllable variable 'call_scratch_address' can
5207 specify the location of a scratch area to be used when GDB
5208 calls a function in the target. This is necessary because the
5209 usual method of putting the scratch area on the stack does not work
5210 in systems that have separate instruction and data spaces.
5212 We integrated changes to support the 29k UDI (Universal Debugger
5213 Interface), but discovered at the last minute that we didn't have all
5214 of the appropriate copyright paperwork. We are working with AMD to
5215 resolve this, and hope to have it available soon.
5219 We have sped up the remote serial line protocol, especially for targets
5220 with lots of registers. It now supports a new `expedited status' ('T')
5221 message which can be used in place of the existing 'S' status message.
5222 This allows the remote stub to send only the registers that GDB
5223 needs to make a quick decision about single-stepping or conditional
5224 breakpoints, eliminating the need to fetch the entire register set for
5225 each instruction being stepped through.
5227 The GDB remote serial protocol now implements a write-through cache for
5228 registers, only re-reading the registers if the target has run.
5230 There is also a new remote serial stub for SPARC processors. You can
5231 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5232 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5233 processor with a serial port.
5237 Configure.in files have become much easier to read and modify. A new
5238 `table driven' format makes it more obvious what configurations are
5239 supported, and what files each one uses.
5243 There is a new opcodes library which will eventually contain all of the
5244 disassembly routines and opcode tables. At present, it only contains
5245 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5246 disassembler (binutils/objdump) to share these routines.
5248 The libiberty library is now copylefted under the GNU Library General
5249 Public License. This allows more liberal use, and was done so libg++
5250 can use it. This makes no difference to GDB, since the Library License
5251 grants all the rights from the General Public License.
5255 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5256 reference to the stabs symbol info used by the debugger. It is (as far
5257 as we know) the only published document on this fascinating topic. We
5258 encourage you to read it, compare it to the stabs information on your
5259 system, and send improvements on the document in general (to
5260 bug-gdb@prep.ai.mit.edu).
5262 And, of course, many bugs have been fixed.
5265 *** Changes in GDB-4.6:
5267 * Better support for C++ function names
5269 GDB now accepts as input the "demangled form" of C++ overloaded function
5270 names and member function names, and can do command completion on such names
5271 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5272 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5273 Make use of command completion, it is your friend.
5275 GDB also now accepts a variety of C++ mangled symbol formats. They are
5276 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5277 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5278 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5279 for the list of formats.
5281 * G++ symbol mangling problem
5283 Recent versions of gcc have a bug in how they emit debugging information for
5284 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5285 directory) can be applied to gcc to fix the problem. Alternatively, if you
5286 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5287 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5288 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5291 * New 'maintenance' command
5293 All of the commands related to hacking GDB internals have been moved out of
5294 the main command set, and now live behind the 'maintenance' command. This
5295 can also be abbreviated as 'mt'. The following changes were made:
5297 dump-me -> maintenance dump-me
5298 info all-breakpoints -> maintenance info breakpoints
5299 printmsyms -> maintenance print msyms
5300 printobjfiles -> maintenance print objfiles
5301 printpsyms -> maintenance print psymbols
5302 printsyms -> maintenance print symbols
5304 The following commands are new:
5306 maintenance demangle Call internal GDB demangler routine to
5307 demangle a C++ link name and prints the result.
5308 maintenance print type Print a type chain for a given symbol
5310 * Change to .gdbinit file processing
5312 We now read the $HOME/.gdbinit file before processing the argv arguments
5313 (e.g. reading symbol files or core files). This allows global parameters to
5314 be set, which will apply during the symbol reading. The ./.gdbinit is still
5315 read after argv processing.
5317 * New hosts supported
5319 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5321 GNU/Linux support i386-unknown-linux or linux
5323 We are also including code to support the HP/PA running BSD and HPUX. This
5324 is almost guaranteed not to work, as we didn't have time to test or build it
5325 for this release. We are including it so that the more adventurous (or
5326 masochistic) of you can play with it. We also had major problems with the
5327 fact that the compiler that we got from HP doesn't support the -g option.
5330 * New targets supported
5332 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5334 * More smarts about finding #include files
5336 GDB now remembers the compilation directory for all include files, and for
5337 all files from which C is generated (like yacc and lex sources). This
5338 greatly improves GDB's ability to find yacc/lex sources, and include files,
5339 especially if you are debugging your program from a directory different from
5340 the one that contains your sources.
5342 We also fixed a bug which caused difficulty with listing and setting
5343 breakpoints in include files which contain C code. (In the past, you had to
5344 try twice in order to list an include file that you hadn't looked at before.)
5346 * Interesting infernals change
5348 GDB now deals with arbitrary numbers of sections, where the symbols for each
5349 section must be relocated relative to that section's landing place in the
5350 target's address space. This work was needed to support ELF with embedded
5351 stabs used by Solaris-2.0.
5353 * Bug fixes (of course!)
5355 There have been loads of fixes for the following things:
5356 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5357 i960, stabs, DOS(GO32), procfs, etc...
5359 See the ChangeLog for details.
5361 *** Changes in GDB-4.5:
5363 * New machines supported (host and target)
5365 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5367 SGI Irix-4.x mips-sgi-irix4 or iris4
5369 * New malloc package
5371 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5372 Mmalloc is capable of handling mutiple heaps of memory. It is also
5373 capable of saving a heap to a file, and then mapping it back in later.
5374 This can be used to greatly speedup the startup of GDB by using a
5375 pre-parsed symbol table which lives in a mmalloc managed heap. For
5376 more details, please read mmalloc/mmalloc.texi.
5380 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5381 'help info proc' for details.
5383 * MIPS ecoff symbol table format
5385 The code that reads MIPS symbol table format is now supported on all hosts.
5386 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5389 * File name changes for MS-DOS
5391 Many files in the config directories have been renamed to make it easier to
5392 support GDB on MS-DOSe systems (which have very restrictive file name
5393 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5394 environment) is close to working but has some remaining problems. Note
5395 that debugging of DOS programs is not supported, due to limitations
5396 in the ``operating system'', but it can be used to host cross-debugging.
5398 * Cross byte order fixes
5400 Many fixes have been made to support cross debugging of Sparc and MIPS
5401 targets from hosts whose byte order differs.
5403 * New -mapped and -readnow options
5405 If memory-mapped files are available on your system through the 'mmap'
5406 system call, you can use the -mapped option on the `file' or
5407 `symbol-file' commands to cause GDB to write the symbols from your
5408 program into a reusable file. If the program you are debugging is
5409 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5410 Future GDB debugging sessions will notice the presence of this file,
5411 and will quickly map in symbol information from it, rather than reading
5412 the symbol table from the executable program. Using the '-mapped'
5413 option in a GDB `file' or `symbol-file' command has the same effect as
5414 starting GDB with the '-mapped' command-line option.
5416 You can cause GDB to read the entire symbol table immediately by using
5417 the '-readnow' option with any of the commands that load symbol table
5418 information (or on the GDB command line). This makes the command
5419 slower, but makes future operations faster.
5421 The -mapped and -readnow options are typically combined in order to
5422 build a `fred.syms' file that contains complete symbol information.
5423 A simple GDB invocation to do nothing but build a `.syms' file for future
5426 gdb -batch -nx -mapped -readnow programname
5428 The `.syms' file is specific to the host machine on which GDB is run.
5429 It holds an exact image of GDB's internal symbol table. It cannot be
5430 shared across multiple host platforms.
5432 * longjmp() handling
5434 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5435 siglongjmp() without losing control. This feature has not yet been ported to
5436 all systems. It currently works on many 386 platforms, all MIPS-based
5437 platforms (SGI, DECstation, etc), and Sun3/4.
5441 Preliminary work has been put in to support the new Solaris OS from Sun. At
5442 this time, it can control and debug processes, but it is not capable of
5447 As always, many many bug fixes. The major areas were with g++, and mipsread.
5448 People using the MIPS-based platforms should experience fewer mysterious
5449 crashes and trashed symbol tables.
5451 *** Changes in GDB-4.4:
5453 * New machines supported (host and target)
5455 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5457 BSD Reno on Vax vax-dec-bsd
5458 Ultrix on Vax vax-dec-ultrix
5460 * New machines supported (target)
5462 AMD 29000 embedded, using EBMON a29k-none-none
5466 GDB continues to improve its handling of C++. `References' work better.
5467 The demangler has also been improved, and now deals with symbols mangled as
5468 per the Annotated C++ Reference Guide.
5470 GDB also now handles `stabs' symbol information embedded in MIPS
5471 `ecoff' symbol tables. Since the ecoff format was not easily
5472 extensible to handle new languages such as C++, this appeared to be a
5473 good way to put C++ debugging info into MIPS binaries. This option
5474 will be supported in the GNU C compiler, version 2, when it is
5477 * New features for SVR4
5479 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5480 shared libraries. Debugging dynamically linked programs should present
5481 only minor differences from debugging statically linked programs.
5483 The `info proc' command will print out information about any process
5484 on an SVR4 system (including the one you are debugging). At the moment,
5485 it prints the address mappings of the process.
5487 If you bring up GDB on another SVR4 system, please send mail to
5488 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5490 * Better dynamic linking support in SunOS
5492 Reading symbols from shared libraries which contain debugging symbols
5493 now works properly. However, there remain issues such as automatic
5494 skipping of `transfer vector' code during function calls, which
5495 make it harder to debug code in a shared library, than to debug the
5496 same code linked statically.
5500 GDB is now using the latest `getopt' routines from the FSF. This
5501 version accepts the -- prefix for options with long names. GDB will
5502 continue to accept the old forms (-option and +option) as well.
5503 Various single letter abbreviations for options have been explicity
5504 added to the option table so that they won't get overshadowed in the
5505 future by other options that begin with the same letter.
5509 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5510 Many assorted bugs have been handled. Many more remain to be handled.
5511 See the various ChangeLog files (primarily in gdb and bfd) for details.
5514 *** Changes in GDB-4.3:
5516 * New machines supported (host and target)
5518 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5519 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5520 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5522 * Almost SCO Unix support
5524 We had hoped to support:
5525 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5526 (except for core file support), but we discovered very late in the release
5527 that it has problems with process groups that render gdb unusable. Sorry
5528 about that. I encourage people to fix it and post the fixes.
5530 * Preliminary ELF and DWARF support
5532 GDB can read ELF object files on System V Release 4, and can handle
5533 debugging records for C, in DWARF format, in ELF files. This support
5534 is preliminary. If you bring up GDB on another SVR4 system, please
5535 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5540 GDB now uses the latest `readline' library. One user-visible change
5541 is that two tabs will list possible command completions, which previously
5542 required typing M-? (meta-question mark, or ESC ?).
5546 The `stepi' bug that many of you noticed has been squashed.
5547 Many bugs in C++ have been handled. Many more remain to be handled.
5548 See the various ChangeLog files (primarily in gdb and bfd) for details.
5550 * State of the MIPS world (in case you wondered):
5552 GDB can understand the symbol tables emitted by the compilers
5553 supplied by most vendors of MIPS-based machines, including DEC. These
5554 symbol tables are in a format that essentially nobody else uses.
5556 Some versions of gcc come with an assembler post-processor called
5557 mips-tfile. This program is required if you want to do source-level
5558 debugging of gcc-compiled programs. I believe FSF does not ship
5559 mips-tfile with gcc version 1, but it will eventually come with gcc
5562 Debugging of g++ output remains a problem. g++ version 1.xx does not
5563 really support it at all. (If you're lucky, you should be able to get
5564 line numbers and stack traces to work, but no parameters or local
5565 variables.) With some work it should be possible to improve the
5568 When gcc version 2 is released, you will have somewhat better luck.
5569 However, even then you will get confusing results for inheritance and
5572 We will eventually provide full debugging of g++ output on
5573 DECstations. This will probably involve some kind of stabs-in-ecoff
5574 encapulation, but the details have not been worked out yet.
5577 *** Changes in GDB-4.2:
5579 * Improved configuration
5581 Only one copy of `configure' exists now, and it is not self-modifying.
5582 Porting BFD is simpler.
5586 The `step' and `next' commands now only stop at the first instruction
5587 of a source line. This prevents the multiple stops that used to occur
5588 in switch statements, for-loops, etc. `Step' continues to stop if a
5589 function that has debugging information is called within the line.
5593 Lots of small bugs fixed. More remain.
5595 * New host supported (not target)
5597 Intel 386 PC clone running Mach i386-none-mach
5600 *** Changes in GDB-4.1:
5602 * Multiple source language support
5604 GDB now has internal scaffolding to handle several source languages.
5605 It determines the type of each source file from its filename extension,
5606 and will switch expression parsing and number formatting to match the
5607 language of the function in the currently selected stack frame.
5608 You can also specifically set the language to be used, with
5609 `set language c' or `set language modula-2'.
5613 GDB now has preliminary support for the GNU Modula-2 compiler,
5614 currently under development at the State University of New York at
5615 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5616 continue through the fall of 1991 and into 1992.
5618 Other Modula-2 compilers are currently not supported, and attempting to
5619 debug programs compiled with them will likely result in an error as the
5620 symbol table is read. Feel free to work on it, though!
5622 There are hooks in GDB for strict type checking and range checking,
5623 in the `Modula-2 philosophy', but they do not currently work.
5627 GDB can now write to executable and core files (e.g. patch
5628 a variable's value). You must turn this switch on, specify
5629 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5630 by assigning a new value to a variable. Modifications take
5633 * Automatic SunOS shared library reading
5635 When you run your program, GDB automatically determines where its
5636 shared libraries (if any) have been loaded, and reads their symbols.
5637 The `share' command is no longer needed. This also works when
5638 examining core files.
5642 You can specify the number of lines that the `list' command shows.
5645 * New machines supported (host and target)
5647 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5648 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5649 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5651 * New hosts supported (not targets)
5653 IBM RT/PC: romp-ibm-aix or rtpc
5655 * New targets supported (not hosts)
5657 AMD 29000 embedded with COFF a29k-none-coff
5658 AMD 29000 embedded with a.out a29k-none-aout
5659 Ultracomputer remote kernel debug a29k-nyu-kern
5661 * New remote interfaces
5667 *** Changes in GDB-4.0:
5671 Wide output is wrapped at good places to make the output more readable.
5673 Gdb now supports cross-debugging from a host machine of one type to a
5674 target machine of another type. Communication with the target system
5675 is over serial lines. The ``target'' command handles connecting to the
5676 remote system; the ``load'' command will download a program into the
5677 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5678 also supports debugging of realtime processes running under VxWorks,
5679 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5680 stub on the target system.
5682 New CPUs supported include the AMD 29000 and Intel 960.
5684 GDB now reads object files and symbol tables via a ``binary file''
5685 library, which allows a single copy of GDB to debug programs of multiple
5686 object file types such as a.out and coff.
5688 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5689 refcard.dvi and refcard.ps are available to format it).
5692 * Control-Variable user interface simplified
5694 All variables that control the operation of the debugger can be set
5695 by the ``set'' command, and displayed by the ``show'' command.
5697 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5698 ``Show prompt'' produces the response:
5699 Gdb's prompt is new-gdb=>.
5701 What follows are the NEW set commands. The command ``help set'' will
5702 print a complete list of old and new set commands. ``help set FOO''
5703 will give a longer description of the variable FOO. ``show'' will show
5704 all of the variable descriptions and their current settings.
5706 confirm on/off: Enables warning questions for operations that are
5707 hard to recover from, e.g. rerunning the program while
5708 it is already running. Default is ON.
5710 editing on/off: Enables EMACS style command line editing
5711 of input. Previous lines can be recalled with
5712 control-P, the current line can be edited with control-B,
5713 you can search for commands with control-R, etc.
5716 history filename NAME: NAME is where the gdb command history
5717 will be stored. The default is .gdb_history,
5718 or the value of the environment variable
5721 history size N: The size, in commands, of the command history. The
5722 default is 256, or the value of the environment variable
5725 history save on/off: If this value is set to ON, the history file will
5726 be saved after exiting gdb. If set to OFF, the
5727 file will not be saved. The default is OFF.
5729 history expansion on/off: If this value is set to ON, then csh-like
5730 history expansion will be performed on
5731 command line input. The default is OFF.
5733 radix N: Sets the default radix for input and output. It can be set
5734 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5735 in the current radix, so "set radix 10" is always a no-op.
5737 height N: This integer value is the number of lines on a page. Default
5738 is 24, the current `stty rows'' setting, or the ``li#''
5739 setting from the termcap entry matching the environment
5742 width N: This integer value is the number of characters on a line.
5743 Default is 80, the current `stty cols'' setting, or the ``co#''
5744 setting from the termcap entry matching the environment
5747 Note: ``set screensize'' is obsolete. Use ``set height'' and
5748 ``set width'' instead.
5750 print address on/off: Print memory addresses in various command displays,
5751 such as stack traces and structure values. Gdb looks
5752 more ``symbolic'' if you turn this off; it looks more
5753 ``machine level'' with it on. Default is ON.
5755 print array on/off: Prettyprint arrays. New convenient format! Default
5758 print demangle on/off: Print C++ symbols in "source" form if on,
5761 print asm-demangle on/off: Same, for assembler level printouts
5764 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5767 * Support for Epoch Environment.
5769 The epoch environment is a version of Emacs v18 with windowing. One
5770 new command, ``inspect'', is identical to ``print'', except that if you
5771 are running in the epoch environment, the value is printed in its own
5775 * Support for Shared Libraries
5777 GDB can now debug programs and core files that use SunOS shared libraries.
5778 Symbols from a shared library cannot be referenced
5779 before the shared library has been linked with the program (this
5780 happens after you type ``run'' and before the function main() is entered).
5781 At any time after this linking (including when examining core files
5782 from dynamically linked programs), gdb reads the symbols from each
5783 shared library when you type the ``sharedlibrary'' command.
5784 It can be abbreviated ``share''.
5786 sharedlibrary REGEXP: Load shared object library symbols for files
5787 matching a unix regular expression. No argument
5788 indicates to load symbols for all shared libraries.
5790 info sharedlibrary: Status of loaded shared libraries.
5795 A watchpoint stops execution of a program whenever the value of an
5796 expression changes. Checking for this slows down execution
5797 tremendously whenever you are in the scope of the expression, but is
5798 quite useful for catching tough ``bit-spreader'' or pointer misuse
5799 problems. Some machines such as the 386 have hardware for doing this
5800 more quickly, and future versions of gdb will use this hardware.
5802 watch EXP: Set a watchpoint (breakpoint) for an expression.
5804 info watchpoints: Information about your watchpoints.
5806 delete N: Deletes watchpoint number N (same as breakpoints).
5807 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5808 enable N: Re-enables watchpoint number N (same as breakpoints).
5811 * C++ multiple inheritance
5813 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5816 * C++ exception handling
5818 Gdb now supports limited C++ exception handling. Besides the existing
5819 ability to breakpoint on an exception handler, gdb can breakpoint on
5820 the raising of an exception (before the stack is peeled back to the
5823 catch FOO: If there is a FOO exception handler in the dynamic scope,
5824 set a breakpoint to catch exceptions which may be raised there.
5825 Multiple exceptions (``catch foo bar baz'') may be caught.
5827 info catch: Lists all exceptions which may be caught in the
5828 current stack frame.
5831 * Minor command changes
5833 The command ``call func (arg, arg, ...)'' now acts like the print
5834 command, except it does not print or save a value if the function's result
5835 is void. This is similar to dbx usage.
5837 The ``up'' and ``down'' commands now always print the frame they end up
5838 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5839 frames without printing.
5841 * New directory command
5843 'dir' now adds directories to the FRONT of the source search path.
5844 The path starts off empty. Source files that contain debug information
5845 about the directory in which they were compiled can be found even
5846 with an empty path; Sun CC and GCC include this information. If GDB can't
5847 find your source file in the current directory, type "dir .".
5849 * Configuring GDB for compilation
5851 For normal use, type ``./configure host''. See README or gdb.texinfo
5854 GDB now handles cross debugging. If you are remotely debugging between
5855 two different machines, type ``./configure host -target=targ''.
5856 Host is the machine where GDB will run; targ is the machine
5857 where the program that you are debugging will run.