1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.8
6 * GDB now supports hardware watchpoints on x86 GNU Hurd.
10 ** You can now access frame registers from Python scripts.
11 ** New attribute 'producer' for gdb.Symtab objects.
13 * New Python-based convenience functions:
15 ** $_caller_is(name [, number_of_frames])
16 ** $_caller_matches(regexp [, number_of_frames])
17 ** $_any_caller_is(name [, number_of_frames])
18 ** $_any_caller_matches(regexp [, number_of_frames])
22 queue-signal signal-name-or-number
23 Queue a signal to be delivered to the thread when it is resumed.
25 * On resume, GDB now always passes the signal the program had stopped
26 for to the thread the signal was sent to, even if the user changed
27 threads before resuming. Previously GDB would often (but not
28 always) deliver the signal to the thread that happens to be current
31 * Conversely, the "signal" command now consistently delivers the
32 requested signal to the current thread. GDB now asks for
33 confirmation if the program had stopped for a signal and the user
34 switched threads meanwhile.
36 * "breakpoint always-inserted" modes "off" and "auto" merged.
38 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
39 won't remove breakpoints from the target until all threads stop,
40 even in non-stop mode. The "auto" mode has been removed, and "off"
41 is now the default mode.
45 ** The -list-thread-groups command outputs an exit-code field for
46 inferiors that have exited.
50 Support for these obsolete configurations has been removed.
55 *** Changes in GDB 7.8
57 * New command line options
60 This is an alias for the --data-directory option.
62 * GDB supports printing and modifying of variable length automatic arrays
63 as specified in ISO C99.
65 * The ARM simulator now supports instruction level tracing
66 with or without disassembly.
70 GDB now has support for scripting using Guile. Whether this is
71 available is determined at configure time.
72 Guile version 2.0 or greater is required.
73 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
75 * New commands (for set/show, see "New options" below)
79 Invoke CODE by passing it to the Guile interpreter.
83 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
85 info auto-load guile-scripts [regexp]
86 Print the list of automatically loaded Guile scripts.
88 * The source command is now capable of sourcing Guile scripts.
89 This feature is dependent on the debugger being built with Guile support.
93 set print symbol-loading (off|brief|full)
94 show print symbol-loading
95 Control whether to print informational messages when loading symbol
96 information for a file. The default is "full", but when debugging
97 programs with large numbers of shared libraries the amount of output
100 set guile print-stack (none|message|full)
101 show guile print-stack
102 Show a stack trace when an error is encountered in a Guile script.
104 set auto-load guile-scripts (on|off)
105 show auto-load guile-scripts
106 Control auto-loading of Guile script files.
108 maint ada set ignore-descriptive-types (on|off)
109 maint ada show ignore-descriptive-types
110 Control whether the debugger should ignore descriptive types in Ada
111 programs. The default is not to ignore the descriptive types. See
112 the user manual for more details on descriptive types and the intended
113 usage of this option.
115 set auto-connect-native-target
117 Control whether GDB is allowed to automatically connect to the
118 native target for the run, attach, etc. commands when not connected
119 to any target yet. See also "target native" below.
121 set record btrace replay-memory-access (read-only|read-write)
122 show record btrace replay-memory-access
123 Control what memory accesses are allowed during replay.
125 maint set target-async (on|off)
126 maint show target-async
127 This controls whether GDB targets operate in syncronous or
128 asyncronous mode. Normally the default is asyncronous, if it is
129 available; but this can be changed to more easily debug problems
130 occurring only in syncronous mode.
132 set mi-async (on|off)
134 Control whether MI asynchronous mode is preferred. This supersedes
135 "set target-async" of previous GDB versions.
137 * "set target-async" is deprecated as a CLI option and is now an alias
138 for "set mi-async" (only puts MI into async mode).
140 * Background execution commands (e.g., "c&", "s&", etc.) are now
141 possible ``out of the box'' if the target supports them. Previously
142 the user would need to explicitly enable the possibility with the
143 "set target-async on" command.
145 * New features in the GDB remote stub, GDBserver
147 ** New option --debug-format=option1[,option2,...] allows one to add
148 additional text to each output. At present only timestamps
149 are supported: --debug-format=timestamps.
150 Timestamps can also be turned on with the
151 "monitor set debug-format timestamps" command from GDB.
153 * The 'record instruction-history' command now starts counting instructions
154 at one. This also affects the instruction ranges reported by the
155 'record function-call-history' command when given the /i modifier.
157 * The command 'record function-call-history' supports a new modifier '/c' to
158 indent the function names based on their call stack depth.
159 The fields for the '/i' and '/l' modifier have been reordered.
160 The source line range is now prefixed with 'at'.
161 The instruction range is now prefixed with 'inst'.
162 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
163 "record instruction-history" and "list" commands.
165 * The ranges given as arguments to the 'record function-call-history' and
166 'record instruction-history' commands are now inclusive.
168 * The btrace record target now supports the 'record goto' command.
169 For locations inside the execution trace, the back trace is computed
170 based on the information stored in the execution trace.
172 * The btrace record target supports limited reverse execution and replay.
173 The target does not record data and therefore does not allow reading
176 * The "catch syscall" command now works on s390*-linux* targets.
178 * The "compare-sections" command is no longer specific to target
179 remote. It now works with all targets.
181 * All native targets are now consistently called "native".
182 Consequently, the "target child", "target GNU", "target djgpp",
183 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
184 commands have been replaced with "target native". The QNX/NTO port
185 leaves the "procfs" target in place and adds a "native" target for
186 consistency with other ports. The impact on users should be minimal
187 as these commands previously either throwed an error, or were
188 no-ops. The target's name is visible in the output of the following
189 commands: "help target", "info target", "info files", "maint print
192 * The "target native" command now connects to the native target. This
193 can be used to launch native programs even when "set
194 auto-connect-native-target" is set to off.
196 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
198 * Support for Intel(R) AVX-512 registers on GNU/Linux.
199 Support displaying and modifying Intel(R) AVX-512 registers
200 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
204 qXfer:btrace:read's annex
205 The qXfer:btrace:read packet supports a new annex 'delta' to read
206 branch trace incrementally.
210 ** Valid Python operations on gdb.Value objects representing
211 structs/classes invoke the corresponding overloaded operators if
213 ** New `Xmethods' feature in the Python API. Xmethods are
214 additional methods or replacements for existing methods of a C++
215 class. This feature is useful for those cases where a method
216 defined in C++ source code could be inlined or optimized out by
217 the compiler, making it unavailable to GDB.
220 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
222 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
223 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
224 its alias "share", instead.
226 * The commands "set remotebaud" and "show remotebaud" are no longer
227 supported. Use "set serial baud" and "show serial baud" (respectively)
232 ** A new option "-gdb-set mi-async" replaces "-gdb-set
233 target-async". The latter is left as a deprecated alias of the
234 former for backward compatibility. If the target supports it,
235 CLI background execution commands are now always possible by
236 default, independently of whether the frontend stated a
237 preference for asynchronous execution with "-gdb-set mi-async".
238 Previously "-gdb-set target-async off" affected both MI execution
239 commands and CLI execution commands.
241 *** Changes in GDB 7.7
243 * Improved support for process record-replay and reverse debugging on
244 arm*-linux* targets. Support for thumb32 and syscall instruction
245 recording has been added.
247 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
249 * GDB now supports Fission DWP file format version 2.
250 http://gcc.gnu.org/wiki/DebugFission
252 * New convenience function "$_isvoid", to check whether an expression
253 is void. A void expression is an expression where the type of the
254 result is "void". For example, some convenience variables may be
255 "void" when evaluated (e.g., "$_exitcode" before the execution of
256 the program being debugged; or an undefined convenience variable).
257 Another example, when calling a function whose return type is
260 * The "maintenance print objfiles" command now takes an optional regexp.
262 * The "catch syscall" command now works on arm*-linux* targets.
264 * GDB now consistently shows "<not saved>" when printing values of
265 registers the debug info indicates have not been saved in the frame
266 and there's nowhere to retrieve them from
267 (callee-saved/call-clobbered registers):
272 (gdb) info registers rax
275 Before, the former would print "<optimized out>", and the latter
276 "*value not available*".
278 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
283 ** Frame filters and frame decorators have been added.
284 ** Temporary breakpoints are now supported.
285 ** Line tables representation has been added.
286 ** New attribute 'parent_type' for gdb.Field objects.
287 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
288 ** New attribute 'name' for gdb.Type objects.
292 Nios II ELF nios2*-*-elf
293 Nios II GNU/Linux nios2*-*-linux
294 Texas Instruments MSP430 msp430*-*-elf
296 * Removed native configurations
298 Support for these a.out NetBSD and OpenBSD obsolete configurations has
299 been removed. ELF variants of these configurations are kept supported.
301 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
302 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
303 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
304 i[34567]86-*-openbsd3.[0-3]
305 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
306 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
307 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
311 Like "catch throw", but catches a re-thrown exception.
313 Renamed from old "maint check-symtabs".
315 Perform consistency checks on symtabs.
317 Expand symtabs matching an optional regexp.
320 Display the details of GDB configure-time options.
322 maint set|show per-command
323 maint set|show per-command space
324 maint set|show per-command time
325 maint set|show per-command symtab
326 Enable display of per-command gdb resource usage.
328 remove-symbol-file FILENAME
329 remove-symbol-file -a ADDRESS
330 Remove a symbol file added via add-symbol-file. The file to remove
331 can be identified by its filename or by an address that lies within
332 the boundaries of this symbol file in memory.
335 info exceptions REGEXP
336 Display the list of Ada exceptions defined in the program being
337 debugged. If provided, only the exceptions whose names match REGEXP
342 set debug symfile off|on
344 Control display of debugging info regarding reading symbol files and
345 symbol tables within those files
347 set print raw frame-arguments
348 show print raw frame-arguments
349 Set/show whether to print frame arguments in raw mode,
350 disregarding any defined pretty-printers.
352 set remote trace-status-packet
353 show remote trace-status-packet
354 Set/show the use of remote protocol qTStatus packet.
358 Control display of debugging messages related to Nios II targets.
362 Control whether target-assisted range stepping is enabled.
364 set startup-with-shell
365 show startup-with-shell
366 Specifies whether Unix child processes are started via a shell or
371 Use the target memory cache for accesses to the code segment. This
372 improves performance of remote debugging (particularly disassembly).
374 * You can now use a literal value 'unlimited' for options that
375 interpret 0 or -1 as meaning "unlimited". E.g., "set
376 trace-buffer-size unlimited" is now an alias for "set
377 trace-buffer-size -1" and "set height unlimited" is now an alias for
380 * The "set debug symtab-create" debugging option of GDB has been changed to
381 accept a verbosity level. 0 means "off", 1 provides basic debugging
382 output, and values of 2 or greater provides more verbose output.
384 * New command-line options
386 Display the details of GDB configure-time options.
388 * The command 'tsave' can now support new option '-ctf' to save trace
389 buffer in Common Trace Format.
391 * Newly installed $prefix/bin/gcore acts as a shell interface for the
394 * GDB now implements the the C++ 'typeid' operator.
396 * The new convenience variable $_exception holds the exception being
397 thrown or caught at an exception-related catchpoint.
399 * The exception-related catchpoints, like "catch throw", now accept a
400 regular expression which can be used to filter exceptions by type.
402 * The new convenience variable $_exitsignal is automatically set to
403 the terminating signal number when the program being debugged dies
404 due to an uncaught signal.
408 ** All MI commands now accept an optional "--language" option.
409 Support for this feature can be verified by using the "-list-features"
410 command, which should contain "language-option".
412 ** The new command -info-gdb-mi-command allows the user to determine
413 whether a GDB/MI command is supported or not.
415 ** The "^error" result record returned when trying to execute an undefined
416 GDB/MI command now provides a variable named "code" whose content is the
417 "undefined-command" error code. Support for this feature can be verified
418 by using the "-list-features" command, which should contain
419 "undefined-command-error-code".
421 ** The -trace-save MI command can optionally save trace buffer in Common
424 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
426 ** The command -data-list-register-values now accepts an optional
427 "--skip-unavailable" option. When used, only the available registers
430 ** The new command -trace-frame-collected dumps collected variables,
431 computed expressions, tvars, memory and registers in a traceframe.
433 ** The commands -stack-list-locals, -stack-list-arguments and
434 -stack-list-variables now accept an option "--skip-unavailable".
435 When used, only the available locals or arguments are displayed.
437 ** The -exec-run command now accepts an optional "--start" option.
438 When used, the command follows the same semantics as the "start"
439 command, stopping the program's execution at the start of its
440 main subprogram. Support for this feature can be verified using
441 the "-list-features" command, which should contain
442 "exec-run-start-option".
444 ** The new commands -catch-assert and -catch-exceptions insert
445 catchpoints stopping the program when Ada exceptions are raised.
447 ** The new command -info-ada-exceptions provides the equivalent of
448 the new "info exceptions" command.
450 * New system-wide configuration scripts
451 A GDB installation now provides scripts suitable for use as system-wide
452 configuration scripts for the following systems:
456 * GDB now supports target-assigned range stepping with remote targets.
457 This improves the performance of stepping source lines by reducing
458 the number of control packets from/to GDB. See "New remote packets"
461 * GDB now understands the element 'tvar' in the XML traceframe info.
462 It has the id of the collected trace state variables.
464 * On S/390 targets that provide the transactional-execution feature,
465 the program interruption transaction diagnostic block (TDB) is now
466 represented as a number of additional "registers" in GDB.
472 The vCont packet supports a new 'r' action, that tells the remote
473 stub to step through an address range itself, without GDB
474 involvemement at each single-step.
476 qXfer:libraries-svr4:read's annex
477 The previously unused annex of the qXfer:libraries-svr4:read packet
478 is now used to support passing an argument list. The remote stub
479 reports support for this argument list to GDB's qSupported query.
480 The defined arguments are "start" and "prev", used to reduce work
481 necessary for library list updating, resulting in significant
484 * New features in the GDB remote stub, GDBserver
486 ** GDBserver now supports target-assisted range stepping. Currently
487 enabled on x86/x86_64 GNU/Linux targets.
489 ** GDBserver now adds element 'tvar' in the XML in the reply to
490 'qXfer:traceframe-info:read'. It has the id of the collected
491 trace state variables.
493 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
496 * New 'z' formatter for printing and examining memory, this displays the
497 value as hexadecimal zero padded on the left to the size of the type.
499 * GDB can now use Windows x64 unwinding data.
501 * The "set remotebaud" command has been replaced by "set serial baud".
502 Similarly, "show remotebaud" has been replaced by "show serial baud".
503 The "set remotebaud" and "show remotebaud" commands are still available
504 to provide backward compatibility with older versions of GDB.
506 *** Changes in GDB 7.6
508 * Target record has been renamed to record-full.
509 Record/replay is now enabled with the "record full" command.
510 This also affects settings that are associated with full record/replay
511 that have been moved from "set/show record" to "set/show record full":
513 set|show record full insn-number-max
514 set|show record full stop-at-limit
515 set|show record full memory-query
517 * A new record target "record-btrace" has been added. The new target
518 uses hardware support to record the control-flow of a process. It
519 does not support replaying the execution, but it implements the
520 below new commands for investigating the recorded execution log.
521 This new recording method can be enabled using:
525 The "record-btrace" target is only available on Intel Atom processors
526 and requires a Linux kernel 2.6.32 or later.
528 * Two new commands have been added for record/replay to give information
529 about the recorded execution without having to replay the execution.
530 The commands are only supported by "record btrace".
532 record instruction-history prints the execution history at
533 instruction granularity
535 record function-call-history prints the execution history at
538 * New native configurations
540 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
541 FreeBSD/powerpc powerpc*-*-freebsd
542 x86_64/Cygwin x86_64-*-cygwin*
543 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
547 ARM AArch64 aarch64*-*-elf
548 ARM AArch64 GNU/Linux aarch64*-*-linux
549 Lynx 178 PowerPC powerpc-*-lynx*178
550 x86_64/Cygwin x86_64-*-cygwin*
551 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
553 * If the configured location of system.gdbinit file (as given by the
554 --with-system-gdbinit option at configure time) is in the
555 data-directory (as specified by --with-gdb-datadir at configure
556 time) or in one of its subdirectories, then GDB will look for the
557 system-wide init file in the directory specified by the
558 --data-directory command-line option.
560 * New command line options:
562 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
563 other initialization files, unlike -nx which disables all of them.
565 * Removed command line options
567 -epoch This was used by the gdb mode in Epoch, an ancient fork of
570 * The 'ptype' and 'whatis' commands now accept an argument to control
573 * 'info proc' now works on some core files.
577 ** Vectors can be created with gdb.Type.vector.
579 ** Python's atexit.register now works in GDB.
581 ** Types can be pretty-printed via a Python API.
583 ** Python 3 is now supported (in addition to Python 2.4 or later)
585 ** New class gdb.Architecture exposes GDB's internal representation
586 of architecture in the Python API.
588 ** New method Frame.architecture returns the gdb.Architecture object
589 corresponding to the frame's architecture.
591 * New Python-based convenience functions:
593 ** $_memeq(buf1, buf2, length)
594 ** $_streq(str1, str2)
596 ** $_regex(str, regex)
598 * The 'cd' command now defaults to using '~' (the home directory) if not
601 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
602 default for GCC since November 2000.
604 * The command 'forward-search' can now be abbreviated as 'fo'.
606 * The command 'info tracepoints' can now display 'installed on target'
607 or 'not installed on target' for each non-pending location of tracepoint.
609 * New configure options
611 --enable-libmcheck/--disable-libmcheck
612 By default, development versions are built with -lmcheck on hosts
613 that support it, in order to help track memory corruption issues.
614 Release versions, on the other hand, are built without -lmcheck
615 by default. The --enable-libmcheck/--disable-libmcheck configure
616 options allow the user to override that default.
617 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
618 This configure option allows the user to build GDB with
619 libbabeltrace using which GDB can read Common Trace Format data.
621 * New commands (for set/show, see "New options" below)
624 Catch signals. This is similar to "handle", but allows commands and
625 conditions to be attached.
628 List the BFDs known to GDB.
630 python-interactive [command]
632 Start a Python interactive prompt, or evaluate the optional command
633 and print the result of expressions.
636 "py" is a new alias for "python".
638 enable type-printer [name]...
639 disable type-printer [name]...
640 Enable or disable type printers.
644 ** For the Renesas Super-H architecture, the "regs" command has been removed
645 (has been deprecated in GDB 7.5), and "info all-registers" should be used
650 set print type methods (on|off)
651 show print type methods
652 Control whether method declarations are displayed by "ptype".
653 The default is to show them.
655 set print type typedefs (on|off)
656 show print type typedefs
657 Control whether typedef definitions are displayed by "ptype".
658 The default is to show them.
660 set filename-display basename|relative|absolute
661 show filename-display
662 Control the way in which filenames is displayed.
663 The default is "relative", which preserves previous behavior.
665 set trace-buffer-size
666 show trace-buffer-size
667 Request target to change the size of trace buffer.
669 set remote trace-buffer-size-packet auto|on|off
670 show remote trace-buffer-size-packet
671 Control the use of the remote protocol `QTBuffer:size' packet.
675 Control display of debugging messages related to ARM AArch64.
678 set debug coff-pe-read
679 show debug coff-pe-read
680 Control display of debugging messages related to reading of COFF/PE
685 Control display of debugging messages related to Mach-O symbols
688 set debug notification
689 show debug notification
690 Control display of debugging info for async remote notification.
694 ** Command parameter changes are now notified using new async record
695 "=cmd-param-changed".
696 ** Trace frame changes caused by command "tfind" are now notified using
697 new async record "=traceframe-changed".
698 ** The creation, deletion and modification of trace state variables
699 are now notified using new async records "=tsv-created",
700 "=tsv-deleted" and "=tsv-modified".
701 ** The start and stop of process record are now notified using new
702 async record "=record-started" and "=record-stopped".
703 ** Memory changes are now notified using new async record
705 ** The data-disassemble command response will include a "fullname" field
706 containing the absolute file name when source has been requested.
707 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
708 command, to allow pattern filling of memory areas.
709 ** New commands "-catch-load"/"-catch-unload" added for intercepting
710 library load/unload events.
711 ** The response to breakpoint commands and breakpoint async records
712 includes an "installed" field containing a boolean state about each
713 non-pending tracepoint location is whether installed on target or not.
714 ** Output of the "-trace-status" command includes a "trace-file" field
715 containing the name of the trace file being examined. This field is
716 optional, and only present when examining a trace file.
717 ** The "fullname" field is now always present along with the "file" field,
718 even if the file cannot be found by GDB.
720 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
721 You must have the LZMA library available when configuring GDB for this
722 feature to be enabled. For more information, see:
723 http://fedoraproject.org/wiki/Features/MiniDebugInfo
728 Set the size of trace buffer. The remote stub reports support for this
729 packet to gdb's qSupported query.
732 Enable Branch Trace Store (BTS)-based branch tracing for the current
733 thread. The remote stub reports support for this packet to gdb's
737 Disable branch tracing for the current thread. The remote stub reports
738 support for this packet to gdb's qSupported query.
741 Read the traced branches for the current thread. The remote stub
742 reports support for this packet to gdb's qSupported query.
744 *** Changes in GDB 7.5
746 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
747 for more x32 ABI info.
749 * GDB now supports access to MIPS DSP registers on Linux targets.
751 * GDB now supports debugging microMIPS binaries.
753 * The "info os" command on GNU/Linux can now display information on
754 several new classes of objects managed by the operating system:
755 "info os procgroups" lists process groups
756 "info os files" lists file descriptors
757 "info os sockets" lists internet-domain sockets
758 "info os shm" lists shared-memory regions
759 "info os semaphores" lists semaphores
760 "info os msg" lists message queues
761 "info os modules" lists loaded kernel modules
763 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
764 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
765 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
766 options and inspect the probe arguments using the new $_probe_arg family
767 of convenience variables. You can obtain more information about SystemTap
768 in <http://sourceware.org/systemtap/>.
770 * GDB now supports reversible debugging on ARM, it allows you to
771 debug basic ARM and THUMB instructions, and provides
772 record/replay support.
774 * The option "symbol-reloading" has been deleted as it is no longer used.
778 ** GDB commands implemented in Python can now be put in command class
781 ** The "maint set python print-stack on|off" is now deleted.
783 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
784 apply "flag enum"-style pretty-printing to any enum.
786 ** gdb.lookup_symbol can now work when there is no current frame.
788 ** gdb.Symbol now has a 'line' attribute, holding the line number in
789 the source at which the symbol was defined.
791 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
792 method 'value'. The former indicates whether the symbol needs a
793 frame in order to compute its value, and the latter computes the
796 ** A new method 'referenced_value' on gdb.Value objects which can
797 dereference pointer as well as C++ reference values.
799 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
800 which return the global and static blocks (as gdb.Block objects),
801 of the underlying symbol table, respectively.
803 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
804 object associated with a PC value.
806 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
807 of the address range occupied by code for the current source line.
809 * Go language support.
810 GDB now supports debugging programs written in the Go programming
813 * GDBserver now supports stdio connections.
814 E.g. (gdb) target remote | ssh myhost gdbserver - hello
816 * The binary "gdbtui" can no longer be built or installed.
817 Use "gdb -tui" instead.
819 * GDB will now print "flag" enums specially. A flag enum is one where
820 all the enumerator values have no bits in common when pairwise
821 "and"ed. When printing a value whose type is a flag enum, GDB will
822 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
823 (gdb) print (enum E) 3
826 * The filename part of a linespec will now match trailing components
827 of a source file name. For example, "break gcc/expr.c:1000" will
828 now set a breakpoint in build/gcc/expr.c, but not
831 * The "info proc" and "generate-core-file" commands will now also
832 work on remote targets connected to GDBserver on Linux.
834 * The command "info catch" has been removed. It has been disabled
837 * The "catch exception" and "catch assert" commands now accept
838 a condition at the end of the command, much like the "break"
839 command does. For instance:
841 (gdb) catch exception Constraint_Error if Barrier = True
843 Previously, it was possible to add a condition to such catchpoints,
844 but it had to be done as a second step, after the catchpoint had been
845 created, using the "condition" command.
847 * The "info static-tracepoint-marker" command will now also work on
848 native Linux targets with in-process agent.
850 * GDB can now set breakpoints on inlined functions.
852 * The .gdb_index section has been updated to include symbols for
853 inlined functions. GDB will ignore older .gdb_index sections by
854 default, which could cause symbol files to be loaded more slowly
855 until their .gdb_index sections can be recreated. The new command
856 "set use-deprecated-index-sections on" will cause GDB to use any older
857 .gdb_index sections it finds. This will restore performance, but the
858 ability to set breakpoints on inlined functions will be lost in symbol
859 files with older .gdb_index sections.
861 The .gdb_index section has also been updated to record more information
862 about each symbol. This speeds up the "info variables", "info functions"
863 and "info types" commands when used with programs having the .gdb_index
864 section, as well as speeding up debugging with shared libraries using
865 the .gdb_index section.
867 * Ada support for GDB/MI Variable Objects has been added.
869 * GDB can now support 'breakpoint always-inserted mode' in 'record'
874 ** New command -info-os is the MI equivalent of "info os".
876 ** Output logs ("set logging" and related) now include MI output.
880 ** "set use-deprecated-index-sections on|off"
881 "show use-deprecated-index-sections on|off"
882 Controls the use of deprecated .gdb_index sections.
884 ** "catch load" and "catch unload" can be used to stop when a shared
885 library is loaded or unloaded, respectively.
887 ** "enable count" can be used to auto-disable a breakpoint after
890 ** "info vtbl" can be used to show the virtual method tables for
891 C++ and Java objects.
893 ** "explore" and its sub commands "explore value" and "explore type"
894 can be used to recursively explore values and types of
895 expressions. These commands are available only if GDB is
896 configured with '--with-python'.
898 ** "info auto-load" shows status of all kinds of auto-loaded files,
899 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
900 sequences of commands files, "info auto-load python-scripts"
901 shows status of auto-loading Python script files,
902 "info auto-load local-gdbinit" shows status of loading init file
903 (.gdbinit) from current directory and "info auto-load libthread-db" shows
904 status of inferior specific thread debugging shared library loading.
906 ** "info auto-load-scripts", "set auto-load-scripts on|off"
907 and "show auto-load-scripts" commands have been deprecated, use their
908 "info auto-load python-scripts", "set auto-load python-scripts on|off"
909 and "show auto-load python-scripts" counterparts instead.
911 ** "dprintf location,format,args..." creates a dynamic printf, which
912 is basically a breakpoint that does a printf and immediately
913 resumes your program's execution, so it is like a printf that you
914 can insert dynamically at runtime instead of at compiletime.
916 ** "set print symbol"
918 Controls whether GDB attempts to display the symbol, if any,
919 corresponding to addresses it prints. This defaults to "on", but
920 you can set it to "off" to restore GDB's previous behavior.
922 * Deprecated commands
924 ** For the Renesas Super-H architecture, the "regs" command has been
925 deprecated, and "info all-registers" should be used instead.
929 Renesas RL78 rl78-*-elf
930 HP OpenVMS ia64 ia64-hp-openvms*
932 * GDBserver supports evaluation of breakpoint conditions. When
933 support is advertised by GDBserver, GDB may be told to send the
934 breakpoint conditions in bytecode form to GDBserver. GDBserver
935 will only report the breakpoint trigger to GDB when its condition
941 show mips compression
942 Select the compressed ISA encoding used in functions that have no symbol
943 information available. The encoding can be set to either of:
946 and is updated automatically from ELF file flags if available.
948 set breakpoint condition-evaluation
949 show breakpoint condition-evaluation
950 Control whether breakpoint conditions are evaluated by GDB ("host") or by
951 GDBserver ("target"). Default option "auto" chooses the most efficient
953 This option can improve debugger efficiency depending on the speed of the
957 Disable auto-loading globally.
960 Show auto-loading setting of all kinds of auto-loaded files.
962 set auto-load gdb-scripts on|off
963 show auto-load gdb-scripts
964 Control auto-loading of GDB canned sequences of commands files.
966 set auto-load python-scripts on|off
967 show auto-load python-scripts
968 Control auto-loading of Python script files.
970 set auto-load local-gdbinit on|off
971 show auto-load local-gdbinit
972 Control loading of init file (.gdbinit) from current directory.
974 set auto-load libthread-db on|off
975 show auto-load libthread-db
976 Control auto-loading of inferior specific thread debugging shared library.
978 set auto-load scripts-directory <dir1>[:<dir2>...]
979 show auto-load scripts-directory
980 Set a list of directories from which to load auto-loaded scripts.
981 Automatically loaded Python scripts and GDB scripts are located in one
982 of the directories listed by this option.
983 The delimiter (':' above) may differ according to the host platform.
985 set auto-load safe-path <dir1>[:<dir2>...]
986 show auto-load safe-path
987 Set a list of directories from which it is safe to auto-load files.
988 The delimiter (':' above) may differ according to the host platform.
990 set debug auto-load on|off
992 Control display of debugging info for auto-loading the files above.
994 set dprintf-style gdb|call|agent
996 Control the way in which a dynamic printf is performed; "gdb"
997 requests a GDB printf command, while "call" causes dprintf to call a
998 function in the inferior. "agent" requests that the target agent
999 (such as GDBserver) do the printing.
1001 set dprintf-function <expr>
1002 show dprintf-function
1003 set dprintf-channel <expr>
1004 show dprintf-channel
1005 Set the function and optional first argument to the call when using
1006 the "call" style of dynamic printf.
1008 set disconnected-dprintf on|off
1009 show disconnected-dprintf
1010 Control whether agent-style dynamic printfs continue to be in effect
1011 after GDB disconnects.
1013 * New configure options
1015 --with-auto-load-dir
1016 Configure default value for the 'set auto-load scripts-directory'
1017 setting above. It defaults to '$debugdir:$datadir/auto-load',
1018 $debugdir representing global debugging info directories (available
1019 via 'show debug-file-directory') and $datadir representing GDB's data
1020 directory (available via 'show data-directory').
1022 --with-auto-load-safe-path
1023 Configure default value for the 'set auto-load safe-path' setting
1024 above. It defaults to the --with-auto-load-dir setting.
1026 --without-auto-load-safe-path
1027 Set 'set auto-load safe-path' to '/', effectively disabling this
1030 * New remote packets
1032 z0/z1 conditional breakpoints extension
1034 The z0/z1 breakpoint insertion packets have been extended to carry
1035 a list of conditional expressions over to the remote stub depending on the
1036 condition evaluation mode. The use of this extension can be controlled
1037 via the "set remote conditional-breakpoints-packet" command.
1041 Specify the signals which the remote stub may pass to the debugged
1042 program without GDB involvement.
1044 * New command line options
1046 --init-command=FILE, -ix Like --command, -x but execute it
1047 before loading inferior.
1048 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1049 execute it before loading inferior.
1051 *** Changes in GDB 7.4
1053 * GDB now handles ambiguous linespecs more consistently; the existing
1054 FILE:LINE support has been expanded to other types of linespecs. A
1055 breakpoint will now be set on all matching locations in all
1056 inferiors, and locations will be added or removed according to
1059 * GDB now allows you to skip uninteresting functions and files when
1060 stepping with the "skip function" and "skip file" commands.
1062 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1063 and "show remote hardware-watchpoint-length-limit". These allows to
1064 set or show the maximum length limit (in bytes) of a remote
1065 target hardware watchpoint.
1067 This allows e.g. to use "unlimited" hardware watchpoints with the
1068 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1069 watchpoints are slower than real hardware watchpoints but are
1070 significantly faster than gdb software watchpoints.
1074 ** The register_pretty_printer function in module gdb.printing now takes
1075 an optional `replace' argument. If True, the new printer replaces any
1078 ** The "maint set python print-stack on|off" command has been
1079 deprecated and will be deleted in GDB 7.5.
1080 A new command: "set python print-stack none|full|message" has
1081 replaced it. Additionally, the default for "print-stack" is
1082 now "message", which just prints the error message without
1085 ** A prompt substitution hook (prompt_hook) is now available to the
1088 ** A new Python module, gdb.prompt has been added to the GDB Python
1089 modules library. This module provides functionality for
1090 escape sequences in prompts (used by set/show
1091 extended-prompt). These escape sequences are replaced by their
1092 corresponding value.
1094 ** Python commands and convenience-functions located in
1095 'data-directory'/python/gdb/command and
1096 'data-directory'/python/gdb/function are now automatically loaded
1099 ** Blocks now provide four new attributes. global_block and
1100 static_block will return the global and static blocks
1101 respectively. is_static and is_global are boolean attributes
1102 that indicate if the block is one of those two types.
1104 ** Symbols now provide the "type" attribute, the type of the symbol.
1106 ** The "gdb.breakpoint" function has been deprecated in favor of
1109 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1110 of a function. This class is based on the "finish" command
1111 available in the CLI.
1113 ** Type objects for struct and union types now allow access to
1114 the fields using standard Python dictionary (mapping) methods.
1115 For example, "some_type['myfield']" now works, as does
1116 "some_type.items()".
1118 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1121 ** A new function, "deep_items" has been added to the gdb.types
1122 module in the GDB Python modules library. This function returns
1123 an iterator over the fields of a struct or union type. Unlike
1124 the standard Python "iteritems" method, it will recursively traverse
1125 any anonymous fields.
1129 ** "*stopped" events can report several new "reason"s, such as
1132 ** Breakpoint changes are now notified using new async records, like
1133 "=breakpoint-modified".
1135 ** New command -ada-task-info.
1137 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1138 $sdir specifies the default system locations of shared libraries.
1139 $pdir specifies the directory where the libpthread used by the application
1142 GDB no longer looks in $sdir and $pdir after it has searched the directories
1143 mentioned in libthread-db-search-path. If you want to search those
1144 directories, they must be specified in libthread-db-search-path.
1145 The default value of libthread-db-search-path on GNU/Linux and Solaris
1146 systems is now "$sdir:$pdir".
1148 $pdir is not supported by gdbserver, it is currently ignored.
1149 $sdir is supported by gdbserver.
1151 * New configure option --with-iconv-bin.
1152 When using the internationalization support like the one in the GNU C
1153 library, GDB will invoke the "iconv" program to get a list of supported
1154 character sets. If this program lives in a non-standard location, one can
1155 use this option to specify where to find it.
1157 * When natively debugging programs on PowerPC BookE processors running
1158 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1159 watchpoints, which specify a mask in addition to an address to watch.
1160 The mask specifies that some bits of an address (the bits which are
1161 reset in the mask) should be ignored when matching the address accessed
1162 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1163 section in the user manual for more details.
1165 * The new option --once causes GDBserver to stop listening for connections once
1166 the first connection is made. The listening port used by GDBserver will
1167 become available after that.
1169 * New commands "info macros" and "alias" have been added.
1171 * New function parameters suffix @entry specifies value of function parameter
1172 at the time the function got called. Entry values are available only since
1178 "!" is now an alias of the "shell" command.
1179 Note that no space is needed between "!" and SHELL COMMAND.
1183 watch EXPRESSION mask MASK_VALUE
1184 The watch command now supports the mask argument which allows creation
1185 of masked watchpoints, if the current architecture supports this feature.
1187 info auto-load-scripts [REGEXP]
1188 This command was formerly named "maintenance print section-scripts".
1189 It is now generally useful and is no longer a maintenance-only command.
1191 info macro [-all] [--] MACRO
1192 The info macro command has new options `-all' and `--'. The first for
1193 printing all definitions of a macro. The second for explicitly specifying
1194 the end of arguments and the beginning of the macro name in case the macro
1195 name starts with a hyphen.
1197 collect[/s] EXPRESSIONS
1198 The tracepoint collect command now takes an optional modifier "/s"
1199 that directs it to dereference pointer-to-character types and
1200 collect the bytes of memory up to a zero byte. The behavior is
1201 similar to what you see when you use the regular print command on a
1202 string. An optional integer following the "/s" sets a bound on the
1203 number of bytes that will be collected.
1206 The trace start command now interprets any supplied arguments as a
1207 note to be recorded with the trace run, with an effect similar to
1208 setting the variable trace-notes.
1211 The trace stop command now interprets any arguments as a note to be
1212 mentioned along with the tstatus report that the trace was stopped
1213 with a command. The effect is similar to setting the variable
1216 * Tracepoints can now be enabled and disabled at any time after a trace
1217 experiment has been started using the standard "enable" and "disable"
1218 commands. It is now possible to start a trace experiment with no enabled
1219 tracepoints; GDB will display a warning, but will allow the experiment to
1220 begin, assuming that tracepoints will be enabled as needed while the trace
1223 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1224 locations with 4-byte instructions, when they were previously
1225 limited to locations with instructions of 5 bytes or longer.
1229 set debug dwarf2-read
1230 show debug dwarf2-read
1231 Turns on or off display of debugging messages related to reading
1232 DWARF debug info. The default is off.
1234 set debug symtab-create
1235 show debug symtab-create
1236 Turns on or off display of debugging messages related to symbol table
1237 creation. The default is off.
1240 show extended-prompt
1241 Set the GDB prompt, and allow escape sequences to be inserted to
1242 display miscellaneous information (see 'help set extended-prompt'
1243 for the list of sequences). This prompt (and any information
1244 accessed through the escape sequences) is updated every time the
1245 prompt is displayed.
1247 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1248 show print entry-values
1249 Set printing of frame argument values at function entry. In some cases
1250 GDB can determine the value of function argument which was passed by the
1251 function caller, even if the value was modified inside the called function.
1253 set debug entry-values
1254 show debug entry-values
1255 Control display of debugging info for determining frame argument values at
1256 function entry and virtual tail call frames.
1258 set basenames-may-differ
1259 show basenames-may-differ
1260 Set whether a source file may have multiple base names.
1261 (A "base name" is the name of a file with the directory part removed.
1262 Example: The base name of "/home/user/hello.c" is "hello.c".)
1263 If set, GDB will canonicalize file names (e.g., expand symlinks)
1264 before comparing them. Canonicalization is an expensive operation,
1265 but it allows the same file be known by more than one base name.
1266 If not set (the default), all source files are assumed to have just
1267 one base name, and gdb will do file name comparisons more efficiently.
1273 Set a user name and notes for the current and any future trace runs.
1274 This is useful for long-running and/or disconnected traces, to
1275 inform others (or yourself) as to who is running the trace, supply
1276 contact information, or otherwise explain what is going on.
1278 set trace-stop-notes
1279 show trace-stop-notes
1280 Set a note attached to the trace run, that is displayed when the
1281 trace has been stopped by a tstop command. This is useful for
1282 instance as an explanation, if you are stopping a trace run that was
1283 started by someone else.
1285 * New remote packets
1289 Dynamically enable a tracepoint in a started trace experiment.
1293 Dynamically disable a tracepoint in a started trace experiment.
1297 Set the user and notes of the trace run.
1301 Query the current status of a tracepoint.
1305 Query the minimum length of instruction at which a fast tracepoint may
1308 * Dcache size (number of lines) and line-size are now runtime-configurable
1309 via "set dcache line" and "set dcache line-size" commands.
1313 Texas Instruments TMS320C6x tic6x-*-*
1317 Renesas RL78 rl78-*-elf
1319 *** Changes in GDB 7.3.1
1321 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1323 *** Changes in GDB 7.3
1325 * GDB has a new command: "thread find [REGEXP]".
1326 It finds the thread id whose name, target id, or thread extra info
1327 matches the given regular expression.
1329 * The "catch syscall" command now works on mips*-linux* targets.
1331 * The -data-disassemble MI command now supports modes 2 and 3 for
1332 dumping the instruction opcodes.
1334 * New command line options
1336 -data-directory DIR Specify DIR as the "data-directory".
1337 This is mostly for testing purposes.
1339 * The "maint set python auto-load on|off" command has been renamed to
1340 "set auto-load-scripts on|off".
1342 * GDB has a new command: "set directories".
1343 It is like the "dir" command except that it replaces the
1344 source path list instead of augmenting it.
1346 * GDB now understands thread names.
1348 On GNU/Linux, "info threads" will display the thread name as set by
1349 prctl or pthread_setname_np.
1351 There is also a new command, "thread name", which can be used to
1352 assign a name internally for GDB to display.
1355 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1356 has been integrated into GDB.
1360 ** The function gdb.Write now accepts an optional keyword 'stream'.
1361 This keyword, when provided, will direct the output to either
1362 stdout, stderr, or GDB's logging output.
1364 ** Parameters can now be be sub-classed in Python, and in particular
1365 you may implement the get_set_doc and get_show_doc functions.
1366 This improves how Parameter set/show documentation is processed
1367 and allows for more dynamic content.
1369 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1370 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1371 have an is_valid method.
1373 ** Breakpoints can now be sub-classed in Python, and in particular
1374 you may implement a 'stop' function that is executed each time
1375 the inferior reaches that breakpoint.
1377 ** New function gdb.lookup_global_symbol looks up a global symbol.
1379 ** GDB values in Python are now callable if the value represents a
1380 function. For example, if 'some_value' represents a function that
1381 takes two integer parameters and returns a value, you can call
1382 that function like so:
1384 result = some_value (10,20)
1386 ** Module gdb.types has been added.
1387 It contains a collection of utilities for working with gdb.Types objects:
1388 get_basic_type, has_field, make_enum_dict.
1390 ** Module gdb.printing has been added.
1391 It contains utilities for writing and registering pretty-printers.
1392 New classes: PrettyPrinter, SubPrettyPrinter,
1393 RegexpCollectionPrettyPrinter.
1394 New function: register_pretty_printer.
1396 ** New commands "info pretty-printers", "enable pretty-printer" and
1397 "disable pretty-printer" have been added.
1399 ** gdb.parameter("directories") is now available.
1401 ** New function gdb.newest_frame returns the newest frame in the
1404 ** The gdb.InferiorThread class has a new "name" attribute. This
1405 holds the thread's name.
1407 ** Python Support for Inferior events.
1408 Python scripts can add observers to be notified of events
1409 occurring in the process being debugged.
1410 The following events are currently supported:
1411 - gdb.events.cont Continue event.
1412 - gdb.events.exited Inferior exited event.
1413 - gdb.events.stop Signal received, and Breakpoint hit events.
1417 ** GDB now puts template parameters in scope when debugging in an
1418 instantiation. For example, if you have:
1420 template<int X> int func (void) { return X; }
1422 then if you step into func<5>, "print X" will show "5". This
1423 feature requires proper debuginfo support from the compiler; it
1424 was added to GCC 4.5.
1426 ** The motion commands "next", "finish", "until", and "advance" now
1427 work better when exceptions are thrown. In particular, GDB will
1428 no longer lose control of the inferior; instead, the GDB will
1429 stop the inferior at the point at which the exception is caught.
1430 This functionality requires a change in the exception handling
1431 code that was introduced in GCC 4.5.
1433 * GDB now follows GCC's rules on accessing volatile objects when
1434 reading or writing target state during expression evaluation.
1435 One notable difference to prior behavior is that "print x = 0"
1436 no longer generates a read of x; the value of the assignment is
1437 now always taken directly from the value being assigned.
1439 * GDB now has some support for using labels in the program's source in
1440 linespecs. For instance, you can use "advance label" to continue
1441 execution to a label.
1443 * GDB now has support for reading and writing a new .gdb_index
1444 section. This section holds a fast index of DWARF debugging
1445 information and can be used to greatly speed up GDB startup and
1446 operation. See the documentation for `save gdb-index' for details.
1448 * The "watch" command now accepts an optional "-location" argument.
1449 When used, this causes GDB to watch the memory referred to by the
1450 expression. Such a watchpoint is never deleted due to it going out
1453 * GDB now supports thread debugging of core dumps on GNU/Linux.
1455 GDB now activates thread debugging using the libthread_db library
1456 when debugging GNU/Linux core dumps, similarly to when debugging
1457 live processes. As a result, when debugging a core dump file, GDB
1458 is now able to display pthread_t ids of threads. For example, "info
1459 threads" shows the same output as when debugging the process when it
1460 was live. In earlier releases, you'd see something like this:
1463 * 1 LWP 6780 main () at main.c:10
1465 While now you see this:
1468 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1470 It is also now possible to inspect TLS variables when debugging core
1473 When debugging a core dump generated on a machine other than the one
1474 used to run GDB, you may need to point GDB at the correct
1475 libthread_db library with the "set libthread-db-search-path"
1476 command. See the user manual for more details on this command.
1478 * When natively debugging programs on PowerPC BookE processors running
1479 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1480 which stop execution of the inferior whenever it executes an instruction
1481 at any address within the specified range. See the "PowerPC Embedded"
1482 section in the user manual for more details.
1484 * New features in the GDB remote stub, GDBserver
1486 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1487 and i686 LynxOS (version 5.x).
1489 ** GDBserver is now supported on Blackfin Linux.
1491 * New native configurations
1493 ia64 HP-UX ia64-*-hpux*
1497 Analog Devices, Inc. Blackfin Processor bfin-*
1499 * Ada task switching is now supported on sparc-elf targets when
1500 debugging a program using the Ravenscar Profile. For more information,
1501 see the "Tasking Support when using the Ravenscar Profile" section
1502 in the GDB user manual.
1504 * Guile support was removed.
1506 * New features in the GNU simulator
1508 ** The --map-info flag lists all known core mappings.
1510 ** CFI flashes may be simulated via the "cfi" device.
1512 *** Changes in GDB 7.2
1514 * Shared library support for remote targets by default
1516 When GDB is configured for a generic, non-OS specific target, like
1517 for example, --target=arm-eabi or one of the many *-*-elf targets,
1518 GDB now queries remote stubs for loaded shared libraries using the
1519 `qXfer:libraries:read' packet. Previously, shared library support
1520 was always disabled for such configurations.
1524 ** Argument Dependent Lookup (ADL)
1526 In C++ ADL lookup directs function search to the namespaces of its
1527 arguments even if the namespace has not been imported.
1537 Here the compiler will search for `foo' in the namespace of 'b'
1538 and find A::foo. GDB now supports this. This construct is commonly
1539 used in the Standard Template Library for operators.
1541 ** Improved User Defined Operator Support
1543 In addition to member operators, GDB now supports lookup of operators
1544 defined in a namespace and imported with a `using' directive, operators
1545 defined in the global scope, operators imported implicitly from an
1546 anonymous namespace, and the ADL operators mentioned in the previous
1548 GDB now also supports proper overload resolution for all the previously
1549 mentioned flavors of operators.
1551 ** static const class members
1553 Printing of static const class members that are initialized in the
1554 class definition has been fixed.
1556 * Windows Thread Information Block access.
1558 On Windows targets, GDB now supports displaying the Windows Thread
1559 Information Block (TIB) structure. This structure is visible either
1560 by using the new command `info w32 thread-information-block' or, by
1561 dereferencing the new convenience variable named `$_tlb', a
1562 thread-specific pointer to the TIB. This feature is also supported
1563 when remote debugging using GDBserver.
1565 * Static tracepoints
1567 Static tracepoints are calls in the user program into a tracing
1568 library. One such library is a port of the LTTng kernel tracer to
1569 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1570 When debugging with GDBserver, GDB now supports combining the GDB
1571 tracepoint machinery with such libraries. For example: the user can
1572 use GDB to probe a static tracepoint marker (a call from the user
1573 program into the tracing library) with the new "strace" command (see
1574 "New commands" below). This creates a "static tracepoint" in the
1575 breakpoint list, that can be manipulated with the same feature set
1576 as fast and regular tracepoints. E.g., collect registers, local and
1577 global variables, collect trace state variables, and define
1578 tracepoint conditions. In addition, the user can collect extra
1579 static tracepoint marker specific data, by collecting the new
1580 $_sdata internal variable. When analyzing the trace buffer, you can
1581 inspect $_sdata like any other variable available to GDB. For more
1582 information, see the "Tracepoints" chapter in GDB user manual. New
1583 remote packets have been defined to support static tracepoints, see
1584 the "New remote packets" section below.
1586 * Better reconstruction of tracepoints after disconnected tracing
1588 GDB will attempt to download the original source form of tracepoint
1589 definitions when starting a trace run, and then will upload these
1590 upon reconnection to the target, resulting in a more accurate
1591 reconstruction of the tracepoints that are in use on the target.
1595 You can now exercise direct control over the ways that GDB can
1596 affect your program. For instance, you can disallow the setting of
1597 breakpoints, so that the program can run continuously (assuming
1598 non-stop mode). In addition, the "observer" variable is available
1599 to switch all of the different controls; in observer mode, GDB
1600 cannot affect the target's behavior at all, which is useful for
1601 tasks like diagnosing live systems in the field.
1603 * The new convenience variable $_thread holds the number of the
1606 * New remote packets
1610 Return the address of the Windows Thread Information Block of a given thread.
1614 In response to several of the tracepoint packets, the target may now
1615 also respond with a number of intermediate `qRelocInsn' request
1616 packets before the final result packet, to have GDB handle
1617 relocating an instruction to execute at a different address. This
1618 is particularly useful for stubs that support fast tracepoints. GDB
1619 reports support for this feature in the qSupported packet.
1623 List static tracepoint markers in the target program.
1627 List static tracepoint markers at a given address in the target
1630 qXfer:statictrace:read
1632 Read the static trace data collected (by a `collect $_sdata'
1633 tracepoint action). The remote stub reports support for this packet
1634 to gdb's qSupported query.
1638 Send the current settings of GDB's permission flags.
1642 Send part of the source (textual) form of a tracepoint definition,
1643 which includes location, conditional, and action list.
1645 * The source command now accepts a -s option to force searching for the
1646 script in the source search path even if the script name specifies
1649 * New features in the GDB remote stub, GDBserver
1651 - GDBserver now support tracepoints (including fast tracepoints, and
1652 static tracepoints). The feature is currently supported by the
1653 i386-linux and amd64-linux builds. See the "Tracepoints support
1654 in gdbserver" section in the manual for more information.
1656 GDBserver JIT compiles the tracepoint's conditional agent
1657 expression bytecode into native code whenever possible for low
1658 overhead dynamic tracepoints conditionals. For such tracepoints,
1659 an expression that examines program state is evaluated when the
1660 tracepoint is reached, in order to determine whether to capture
1661 trace data. If the condition is simple and false, processing the
1662 tracepoint finishes very quickly and no data is gathered.
1664 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1665 for static tracepoints support.
1667 - GDBserver now supports x86_64 Windows 64-bit debugging.
1669 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1670 it understands register description.
1672 * The --batch flag now disables pagination and queries.
1674 * X86 general purpose registers
1676 GDB now supports reading/writing byte, word and double-word x86
1677 general purpose registers directly. This means you can use, say,
1678 $ah or $ax to refer, respectively, to the byte register AH and
1679 16-bit word register AX that are actually portions of the 32-bit
1680 register EAX or 64-bit register RAX.
1682 * The `commands' command now accepts a range of breakpoints to modify.
1683 A plain `commands' following a command that creates multiple
1684 breakpoints affects all the breakpoints set by that command. This
1685 applies to breakpoints set by `rbreak', and also applies when a
1686 single `break' command creates multiple breakpoints (e.g.,
1687 breakpoints on overloaded c++ functions).
1689 * The `rbreak' command now accepts a filename specification as part of
1690 its argument, limiting the functions selected by the regex to those
1691 in the specified file.
1693 * Support for remote debugging Windows and SymbianOS shared libraries
1694 from Unix hosts has been improved. Non Windows GDB builds now can
1695 understand target reported file names that follow MS-DOS based file
1696 system semantics, such as file names that include drive letters and
1697 use the backslash character as directory separator. This makes it
1698 possible to transparently use the "set sysroot" and "set
1699 solib-search-path" on Unix hosts to point as host copies of the
1700 target's shared libraries. See the new command "set
1701 target-file-system-kind" described below, and the "Commands to
1702 specify files" section in the user manual for more information.
1706 eval template, expressions...
1707 Convert the values of one or more expressions under the control
1708 of the string template to a command line, and call it.
1710 set target-file-system-kind unix|dos-based|auto
1711 show target-file-system-kind
1712 Set or show the assumed file system kind for target reported file
1715 save breakpoints <filename>
1716 Save all current breakpoint definitions to a file suitable for use
1717 in a later debugging session. To read the saved breakpoint
1718 definitions, use the `source' command.
1720 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1723 info static-tracepoint-markers
1724 Display information about static tracepoint markers in the target.
1726 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1727 Define a static tracepoint by probing a marker at the given
1728 function, line, address, or marker ID.
1732 Enable and disable observer mode.
1734 set may-write-registers on|off
1735 set may-write-memory on|off
1736 set may-insert-breakpoints on|off
1737 set may-insert-tracepoints on|off
1738 set may-insert-fast-tracepoints on|off
1739 set may-interrupt on|off
1740 Set individual permissions for GDB effects on the target. Note that
1741 some of these settings can have undesirable or surprising
1742 consequences, particularly when changed in the middle of a session.
1743 For instance, disabling the writing of memory can prevent
1744 breakpoints from being inserted, cause single-stepping to fail, or
1745 even crash your program, if you disable after breakpoints have been
1746 inserted. However, GDB should not crash.
1748 set record memory-query on|off
1749 show record memory-query
1750 Control whether to stop the inferior if memory changes caused
1751 by an instruction cannot be recorded.
1756 The disassemble command now supports "start,+length" form of two arguments.
1760 ** GDB now provides a new directory location, called the python directory,
1761 where Python scripts written for GDB can be installed. The location
1762 of that directory is <data-directory>/python, where <data-directory>
1763 is the GDB data directory. For more details, see section `Scripting
1764 GDB using Python' in the manual.
1766 ** The GDB Python API now has access to breakpoints, symbols, symbol
1767 tables, program spaces, inferiors, threads and frame's code blocks.
1768 Additionally, GDB Parameters can now be created from the API, and
1769 manipulated via set/show in the CLI.
1771 ** New functions gdb.target_charset, gdb.target_wide_charset,
1772 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1774 ** New exception gdb.GdbError.
1776 ** Pretty-printers are now also looked up in the current program space.
1778 ** Pretty-printers can now be individually enabled and disabled.
1780 ** GDB now looks for names of Python scripts to auto-load in a
1781 special section named `.debug_gdb_scripts', in addition to looking
1782 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1784 * Tracepoint actions were unified with breakpoint commands. In particular,
1785 there are no longer differences in "info break" output for breakpoints and
1786 tracepoints and the "commands" command can be used for both tracepoints and
1787 regular breakpoints.
1791 ARM Symbian arm*-*-symbianelf*
1793 * D language support.
1794 GDB now supports debugging programs written in the D programming
1797 * GDB now supports the extended ptrace interface for PowerPC which is
1798 available since Linux kernel version 2.6.34. This automatically enables
1799 any hardware breakpoints and additional hardware watchpoints available in
1800 the processor. The old ptrace interface exposes just one hardware
1801 watchpoint and no hardware breakpoints.
1803 * GDB is now able to use the Data Value Compare (DVC) register available on
1804 embedded PowerPC processors to implement in hardware simple watchpoint
1805 conditions of the form:
1807 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1809 This works in native GDB running on Linux kernels with the extended ptrace
1810 interface mentioned above.
1812 *** Changes in GDB 7.1
1816 ** Namespace Support
1818 GDB now supports importing of namespaces in C++. This enables the
1819 user to inspect variables from imported namespaces. Support for
1820 namepace aliasing has also been added. So, if a namespace is
1821 aliased in the current scope (e.g. namepace C=A; ) the user can
1822 print variables using the alias (e.g. (gdb) print C::x).
1826 All known bugs relating to the printing of virtual base class were
1827 fixed. It is now possible to call overloaded static methods using a
1832 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1833 and reinterpret_cast<> are now handled by the C++ expression parser.
1837 Xilinx MicroBlaze microblaze-*-*
1842 Xilinx MicroBlaze microblaze
1845 * Multi-program debugging.
1847 GDB now has support for multi-program (a.k.a. multi-executable or
1848 multi-exec) debugging. This allows for debugging multiple inferiors
1849 simultaneously each running a different program under the same GDB
1850 session. See "Debugging Multiple Inferiors and Programs" in the
1851 manual for more information. This implied some user visible changes
1852 in the multi-inferior support. For example, "info inferiors" now
1853 lists inferiors that are not running yet or that have exited
1854 already. See also "New commands" and "New options" below.
1856 * New tracing features
1858 GDB's tracepoint facility now includes several new features:
1860 ** Trace state variables
1862 GDB tracepoints now include support for trace state variables, which
1863 are variables managed by the target agent during a tracing
1864 experiment. They are useful for tracepoints that trigger each
1865 other, so for instance one tracepoint can count hits in a variable,
1866 and then a second tracepoint has a condition that is true when the
1867 count reaches a particular value. Trace state variables share the
1868 $-syntax of GDB convenience variables, and can appear in both
1869 tracepoint actions and condition expressions. Use the "tvariable"
1870 command to create, and "info tvariables" to view; see "Trace State
1871 Variables" in the manual for more detail.
1875 GDB now includes an option for defining fast tracepoints, which
1876 targets may implement more efficiently, such as by installing a jump
1877 into the target agent rather than a trap instruction. The resulting
1878 speedup can be by two orders of magnitude or more, although the
1879 tradeoff is that some program locations on some target architectures
1880 might not allow fast tracepoint installation, for instance if the
1881 instruction to be replaced is shorter than the jump. To request a
1882 fast tracepoint, use the "ftrace" command, with syntax identical to
1883 the regular trace command.
1885 ** Disconnected tracing
1887 It is now possible to detach GDB from the target while it is running
1888 a trace experiment, then reconnect later to see how the experiment
1889 is going. In addition, a new variable disconnected-tracing lets you
1890 tell the target agent whether to continue running a trace if the
1891 connection is lost unexpectedly.
1895 GDB now has the ability to save the trace buffer into a file, and
1896 then use that file as a target, similarly to you can do with
1897 corefiles. You can select trace frames, print data that was
1898 collected in them, and use tstatus to display the state of the
1899 tracing run at the moment that it was saved. To create a trace
1900 file, use "tsave <filename>", and to use it, do "target tfile
1903 ** Circular trace buffer
1905 You can ask the target agent to handle the trace buffer as a
1906 circular buffer, discarding the oldest trace frames to make room for
1907 newer ones, by setting circular-trace-buffer to on. This feature may
1908 not be available for all target agents.
1913 The disassemble command, when invoked with two arguments, now requires
1914 the arguments to be comma-separated.
1917 The info variables command now displays variable definitions. Files
1918 which only declare a variable are not shown.
1921 The source command is now capable of sourcing Python scripts.
1922 This feature is dependent on the debugger being build with Python
1925 Related to this enhancement is also the introduction of a new command
1926 "set script-extension" (see below).
1928 * New commands (for set/show, see "New options" below)
1930 record save [<FILENAME>]
1931 Save a file (in core file format) containing the process record
1932 execution log for replay debugging at a later time.
1934 record restore <FILENAME>
1935 Restore the process record execution log that was saved at an
1936 earlier time, for replay debugging.
1938 add-inferior [-copies <N>] [-exec <FILENAME>]
1941 clone-inferior [-copies <N>] [ID]
1942 Make a new inferior ready to execute the same program another
1943 inferior has loaded.
1948 maint info program-spaces
1949 List the program spaces loaded into GDB.
1951 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1952 show remote interrupt-sequence
1953 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1954 as the sequence to the remote target in order to interrupt the execution.
1955 Ctrl-C is a default. Some system prefers BREAK which is high level of
1956 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1957 Magic SysRq g. It is BREAK signal and character 'g'.
1959 set remote interrupt-on-connect [on | off]
1960 show remote interrupt-on-connect
1961 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1962 remote target when gdb connects to it. This is needed when you debug
1965 set remotebreak [on | off]
1967 Deprecated. Use "set/show remote interrupt-sequence" instead.
1969 tvariable $NAME [ = EXP ]
1970 Create or modify a trace state variable.
1973 List trace state variables and their values.
1975 delete tvariable $NAME ...
1976 Delete one or more trace state variables.
1979 Evaluate the given expressions without collecting anything into the
1980 trace buffer. (Valid in tracepoint actions only.)
1982 ftrace FN / FILE:LINE / *ADDR
1983 Define a fast tracepoint at the given function, line, or address.
1985 * New expression syntax
1987 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1988 GDB now parses 0b101010 identically with 42.
1992 set follow-exec-mode new|same
1993 show follow-exec-mode
1994 Control whether GDB reuses the same inferior across an exec call or
1995 creates a new one. This is useful to be able to restart the old
1996 executable after the inferior having done an exec call.
1998 set default-collect EXPR, ...
1999 show default-collect
2000 Define a list of expressions to be collected at each tracepoint.
2001 This is a useful way to ensure essential items are not overlooked,
2002 such as registers or a critical global variable.
2004 set disconnected-tracing
2005 show disconnected-tracing
2006 If set to 1, the target is instructed to continue tracing if it
2007 loses its connection to GDB. If 0, the target is to stop tracing
2010 set circular-trace-buffer
2011 show circular-trace-buffer
2012 If set to on, the target is instructed to use a circular trace buffer
2013 and discard the oldest trace frames instead of stopping the trace due
2014 to a full trace buffer. If set to off, the trace stops when the buffer
2015 fills up. Some targets may not support this.
2017 set script-extension off|soft|strict
2018 show script-extension
2019 If set to "off", the debugger does not perform any script language
2020 recognition, and all sourced files are assumed to be GDB scripts.
2021 If set to "soft" (the default), files are sourced according to
2022 filename extension, falling back to GDB scripts if the first
2024 If set to "strict", files are sourced according to filename extension.
2026 set ada trust-PAD-over-XVS on|off
2027 show ada trust-PAD-over-XVS
2028 If off, activate a workaround against a bug in the debugging information
2029 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2030 the GCC sources for more information about the GNAT encoding and
2031 PAD types in particular). It is always safe to set this option to
2032 off, but this introduces a slight performance penalty. The default
2035 * Python API Improvements
2037 ** GDB provides the new class gdb.LazyString. This is useful in
2038 some pretty-printing cases. The new method gdb.Value.lazy_string
2039 provides a simple way to create objects of this type.
2041 ** The fields returned by gdb.Type.fields now have an
2042 `is_base_class' attribute.
2044 ** The new method gdb.Type.range returns the range of an array type.
2046 ** The new method gdb.parse_and_eval can be used to parse and
2047 evaluate an expression.
2049 * New remote packets
2052 Define a trace state variable.
2055 Get the current value of a trace state variable.
2058 Set desired tracing behavior upon disconnection.
2061 Set the trace buffer to be linear or circular.
2064 Get data about the tracepoints currently in use.
2068 Process record now works correctly with hardware watchpoints.
2070 Multiple bug fixes have been made to the mips-irix port, making it
2071 much more reliable. In particular:
2072 - Debugging threaded applications is now possible again. Previously,
2073 GDB would hang while starting the program, or while waiting for
2074 the program to stop at a breakpoint.
2075 - Attaching to a running process no longer hangs.
2076 - An error occurring while loading a core file has been fixed.
2077 - Changing the value of the PC register now works again. This fixes
2078 problems observed when using the "jump" command, or when calling
2079 a function from GDB, or even when assigning a new value to $pc.
2080 - With the "finish" and "return" commands, the return value for functions
2081 returning a small array is now correctly printed.
2082 - It is now possible to break on shared library code which gets executed
2083 during a shared library init phase (code executed while executing
2084 their .init section). Previously, the breakpoint would have no effect.
2085 - GDB is now able to backtrace through the signal handler for
2086 non-threaded programs.
2088 PIE (Position Independent Executable) programs debugging is now supported.
2089 This includes debugging execution of PIC (Position Independent Code) shared
2090 libraries although for that, it should be possible to run such libraries as an
2093 *** Changes in GDB 7.0
2095 * GDB now has an interface for JIT compilation. Applications that
2096 dynamically generate code can create symbol files in memory and register
2097 them with GDB. For users, the feature should work transparently, and
2098 for JIT developers, the interface is documented in the GDB manual in the
2099 "JIT Compilation Interface" chapter.
2101 * Tracepoints may now be conditional. The syntax is as for
2102 breakpoints; either an "if" clause appended to the "trace" command,
2103 or the "condition" command is available. GDB sends the condition to
2104 the target for evaluation using the same bytecode format as is used
2105 for tracepoint actions.
2107 * The disassemble command now supports: an optional /r modifier, print the
2108 raw instructions in hex as well as in symbolic form, and an optional /m
2109 modifier to print mixed source+assembly.
2111 * Process record and replay
2113 In a architecture environment that supports ``process record and
2114 replay'', ``process record and replay'' target can record a log of
2115 the process execution, and replay it with both forward and reverse
2118 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2119 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2120 set execution-direction {forward|reverse}, for targets that support
2123 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2124 feature is available with a native GDB running on kernel version
2127 * GDB now has support for multi-byte and wide character sets on the
2128 target. Strings whose character type is wchar_t, char16_t, or
2129 char32_t are now correctly printed. GDB supports wide- and unicode-
2130 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2131 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2132 `printf'. This feature requires iconv to work properly; if your
2133 system does not have a working iconv, GDB can use GNU libiconv. See
2134 the installation instructions for more information.
2136 * GDB now supports automatic retrieval of shared library files from
2137 remote targets. To use this feature, specify a system root that begins
2138 with the `remote:' prefix, either via the `set sysroot' command or via
2139 the `--with-sysroot' configure-time option.
2141 * "info sharedlibrary" now takes an optional regex of libraries to show,
2142 and it now reports if a shared library has no debugging information.
2144 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2145 now complete on file names.
2147 * When completing in expressions, gdb will attempt to limit
2148 completions to allowable structure or union fields, where appropriate.
2149 For instance, consider:
2151 # struct example { int f1; double f2; };
2152 # struct example variable;
2155 If the user types TAB at the end of this command line, the available
2156 completions will be "f1" and "f2".
2158 * Inlined functions are now supported. They show up in backtraces, and
2159 the "step", "next", and "finish" commands handle them automatically.
2161 * GDB now supports the token-splicing (##) and stringification (#)
2162 operators when expanding macros. It also supports variable-arity
2165 * GDB now supports inspecting extra signal information, exported by
2166 the new $_siginfo convenience variable. The feature is currently
2167 implemented on linux ARM, i386 and amd64.
2169 * GDB can now display the VFP floating point registers and NEON vector
2170 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2171 can provide these registers (requires Linux 2.6.30 or later). Remote
2172 and simulator targets may also provide them.
2174 * New remote packets
2177 Search memory for a sequence of bytes.
2180 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2181 operation over reliable transport links. Use of this packet is
2182 controlled by the `set remote noack-packet' command.
2185 Kill the process with the specified process ID. Use this in preference
2186 to `k' when multiprocess protocol extensions are supported.
2189 Obtains additional operating system information
2193 Read or write additional signal information.
2195 * Removed remote protocol undocumented extension
2197 An undocumented extension to the remote protocol's `S' stop reply
2198 packet that permited the stub to pass a process id was removed.
2199 Remote servers should use the `T' stop reply packet instead.
2201 * GDB now supports multiple function calling conventions according to the
2202 DWARF-2 DW_AT_calling_convention function attribute.
2204 * The SH target utilizes the aforementioned change to distinguish between gcc
2205 and Renesas calling convention. It also adds the new CLI commands
2206 `set/show sh calling-convention'.
2208 * GDB can now read compressed debug sections, as produced by GNU gold
2209 with the --compress-debug-sections=zlib flag.
2211 * 64-bit core files are now supported on AIX.
2213 * Thread switching is now supported on Tru64.
2215 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2216 which will be allocated using malloc later in program execution.
2218 * The qXfer:libraries:read remote procotol packet now allows passing a
2219 list of section offsets.
2221 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2222 conditions handling signals delivered during attach or thread creation
2223 have also been fixed.
2225 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2226 From the user's standpoint, all unqualified instances of True and False
2227 are treated as the standard definitions, regardless of context.
2229 * GDB now parses C++ symbol and type names more flexibly. For
2232 template<typename T> class C { };
2235 GDB will now correctly handle all of:
2237 ptype C<char const *>
2238 ptype C<char const*>
2239 ptype C<const char *>
2240 ptype C<const char*>
2242 * New features in the GDB remote stub, gdbserver
2244 - The "--wrapper" command-line argument tells gdbserver to use a
2245 wrapper program to launch programs for debugging.
2247 - On PowerPC and S/390 targets, it is now possible to use a single
2248 gdbserver executable to debug both 32-bit and 64-bit programs.
2249 (This requires gdbserver itself to be built as a 64-bit executable.)
2251 - gdbserver uses the new noack protocol mode for TCP connections to
2252 reduce communications latency, if also supported and enabled in GDB.
2254 - Support for the sparc64-linux-gnu target is now included in
2257 - The amd64-linux build of gdbserver now supports debugging both
2258 32-bit and 64-bit programs.
2260 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2261 now support hardware watchpoints, and will use them automatically
2266 GDB now has support for scripting using Python. Whether this is
2267 available is determined at configure time.
2269 New GDB commands can now be written in Python.
2271 * Ada tasking support
2273 Ada tasks can now be inspected in GDB. The following commands have
2277 Print the list of Ada tasks.
2279 Print detailed information about task number N.
2281 Print the task number of the current task.
2283 Switch the context of debugging to task number N.
2285 * Support for user-defined prefixed commands. The "define" command can
2286 add new commands to existing prefixes, e.g. "target".
2288 * Multi-inferior, multi-process debugging.
2290 GDB now has generalized support for multi-inferior debugging. See
2291 "Debugging Multiple Inferiors" in the manual for more information.
2292 Although availability still depends on target support, the command
2293 set is more uniform now. The GNU/Linux specific multi-forks support
2294 has been migrated to this new framework. This implied some user
2295 visible changes; see "New commands" and also "Removed commands"
2298 * Target descriptions can now describe the target OS ABI. See the
2299 "Target Description Format" section in the user manual for more
2302 * Target descriptions can now describe "compatible" architectures
2303 to indicate that the target can execute applications for a different
2304 architecture in addition to those for the main target architecture.
2305 See the "Target Description Format" section in the user manual for
2308 * Multi-architecture debugging.
2310 GDB now includes general supports for debugging applications on
2311 hybrid systems that use more than one single processor architecture
2312 at the same time. Each such hybrid architecture still requires
2313 specific support to be added. The only hybrid architecture supported
2314 in this version of GDB is the Cell Broadband Engine.
2316 * GDB now supports integrated debugging of Cell/B.E. applications that
2317 use both the PPU and SPU architectures. To enable support for hybrid
2318 Cell/B.E. debugging, you need to configure GDB to support both the
2319 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2320 --enable-targets configure option.
2322 * Non-stop mode debugging.
2324 For some targets, GDB now supports an optional mode of operation in
2325 which you can examine stopped threads while other threads continue
2326 to execute freely. This is referred to as non-stop mode, with the
2327 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2328 section in the user manual for more information.
2330 To be able to support remote non-stop debugging, a remote stub needs
2331 to implement the non-stop mode remote protocol extensions, as
2332 described in the "Remote Non-Stop" section of the user manual. The
2333 GDB remote stub, gdbserver, has been adjusted to support these
2334 extensions on linux targets.
2336 * New commands (for set/show, see "New options" below)
2338 catch syscall [NAME(S) | NUMBER(S)]
2339 Catch system calls. Arguments, which should be names of system
2340 calls or their numbers, mean catch only those syscalls. Without
2341 arguments, every syscall will be caught. When the inferior issues
2342 any of the specified syscalls, GDB will stop and announce the system
2343 call, both when it is called and when its call returns. This
2344 feature is currently available with a native GDB running on the
2345 Linux Kernel, under the following architectures: x86, x86_64,
2346 PowerPC and PowerPC64.
2348 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2350 Search memory for a sequence of bytes.
2352 maint set python print-stack
2353 maint show python print-stack
2354 Show a stack trace when an error is encountered in a Python script.
2357 Invoke CODE by passing it to the Python interpreter.
2362 These allow macros to be defined, undefined, and listed
2366 Show operating system information about processes.
2369 List the inferiors currently under GDB's control.
2372 Switch focus to inferior number NUM.
2375 Detach from inferior number NUM.
2378 Kill inferior number NUM.
2382 set spu stop-on-load
2383 show spu stop-on-load
2384 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2386 set spu auto-flush-cache
2387 show spu auto-flush-cache
2388 Control whether to automatically flush the software-managed cache
2389 during Cell/B.E. debugging.
2391 set sh calling-convention
2392 show sh calling-convention
2393 Control the calling convention used when calling SH target functions.
2396 show debug timestamp
2397 Control display of timestamps with GDB debugging output.
2399 set disassemble-next-line
2400 show disassemble-next-line
2401 Control display of disassembled source lines or instructions when
2404 set remote noack-packet
2405 show remote noack-packet
2406 Set/show the use of remote protocol QStartNoAckMode packet. See above
2407 under "New remote packets."
2409 set remote query-attached-packet
2410 show remote query-attached-packet
2411 Control use of remote protocol `qAttached' (query-attached) packet.
2413 set remote read-siginfo-object
2414 show remote read-siginfo-object
2415 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2418 set remote write-siginfo-object
2419 show remote write-siginfo-object
2420 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2423 set remote reverse-continue
2424 show remote reverse-continue
2425 Control use of remote protocol 'bc' (reverse-continue) packet.
2427 set remote reverse-step
2428 show remote reverse-step
2429 Control use of remote protocol 'bs' (reverse-step) packet.
2431 set displaced-stepping
2432 show displaced-stepping
2433 Control displaced stepping mode. Displaced stepping is a way to
2434 single-step over breakpoints without removing them from the debuggee.
2435 Also known as "out-of-line single-stepping".
2438 show debug displaced
2439 Control display of debugging info for displaced stepping.
2441 maint set internal-error
2442 maint show internal-error
2443 Control what GDB does when an internal error is detected.
2445 maint set internal-warning
2446 maint show internal-warning
2447 Control what GDB does when an internal warning is detected.
2452 Use a wrapper program to launch programs for debugging.
2454 set multiple-symbols (all|ask|cancel)
2455 show multiple-symbols
2456 The value of this variable can be changed to adjust the debugger behavior
2457 when an expression or a breakpoint location contains an ambiguous symbol
2458 name (an overloaded function name, for instance).
2460 set breakpoint always-inserted
2461 show breakpoint always-inserted
2462 Keep breakpoints always inserted in the target, as opposed to inserting
2463 them when resuming the target, and removing them when the target stops.
2464 This option can improve debugger performance on slow remote targets.
2466 set arm fallback-mode (arm|thumb|auto)
2467 show arm fallback-mode
2468 set arm force-mode (arm|thumb|auto)
2470 These commands control how ARM GDB determines whether instructions
2471 are ARM or Thumb. The default for both settings is auto, which uses
2472 the current CPSR value for instructions without symbols; previous
2473 versions of GDB behaved as if "set arm fallback-mode arm".
2475 set disable-randomization
2476 show disable-randomization
2477 Standalone programs run with the virtual address space randomization enabled
2478 by default on some platforms. This option keeps the addresses stable across
2479 multiple debugging sessions.
2483 Control whether other threads are stopped or not when some thread hits
2488 Requests that asynchronous execution is enabled in the target, if available.
2489 In this case, it's possible to resume target in the background, and interact
2490 with GDB while the target is running. "show target-async" displays the
2491 current state of asynchronous execution of the target.
2493 set target-wide-charset
2494 show target-wide-charset
2495 The target-wide-charset is the name of the character set that GDB
2496 uses when printing characters whose type is wchar_t.
2498 set tcp auto-retry (on|off)
2500 set tcp connect-timeout
2501 show tcp connect-timeout
2502 These commands allow GDB to retry failed TCP connections to a remote stub
2503 with a specified timeout period; this is useful if the stub is launched
2504 in parallel with GDB but may not be ready to accept connections immediately.
2506 set libthread-db-search-path
2507 show libthread-db-search-path
2508 Control list of directories which GDB will search for appropriate
2511 set schedule-multiple (on|off)
2512 show schedule-multiple
2513 Allow GDB to resume all threads of all processes or only threads of
2514 the current process.
2518 Use more aggressive caching for accesses to the stack. This improves
2519 performance of remote debugging (particularly backtraces) without
2520 affecting correctness.
2522 set interactive-mode (on|off|auto)
2523 show interactive-mode
2524 Control whether GDB runs in interactive mode (on) or not (off).
2525 When in interactive mode, GDB waits for the user to answer all
2526 queries. Otherwise, GDB does not wait and assumes the default
2527 answer. When set to auto (the default), GDB determines which
2528 mode to use based on the stdin settings.
2533 For program forks, this is replaced by the new more generic `info
2534 inferiors' command. To list checkpoints, you can still use the
2535 `info checkpoints' command, which was an alias for the `info forks'
2539 Replaced by the new `inferior' command. To switch between
2540 checkpoints, you can still use the `restart' command, which was an
2541 alias for the `fork' command.
2544 This is removed, since some targets don't have a notion of
2545 processes. To switch between processes, you can still use the
2546 `inferior' command using GDB's own inferior number.
2549 For program forks, this is replaced by the new more generic `kill
2550 inferior' command. To delete a checkpoint, you can still use the
2551 `delete checkpoint' command, which was an alias for the `delete
2555 For program forks, this is replaced by the new more generic `detach
2556 inferior' command. To detach a checkpoint, you can still use the
2557 `detach checkpoint' command, which was an alias for the `detach
2560 * New native configurations
2562 x86/x86_64 Darwin i[34567]86-*-darwin*
2564 x86_64 MinGW x86_64-*-mingw*
2568 Lattice Mico32 lm32-*
2569 x86 DICOS i[34567]86-*-dicos*
2570 x86_64 DICOS x86_64-*-dicos*
2573 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2574 (mingw32ce) debugging.
2580 These commands were actually not implemented on any target.
2582 *** Changes in GDB 6.8
2584 * New native configurations
2586 NetBSD/hppa hppa*-*netbsd*
2587 Xtensa GNU/Linux xtensa*-*-linux*
2591 NetBSD/hppa hppa*-*-netbsd*
2592 Xtensa GNU/Lunux xtensa*-*-linux*
2594 * Change in command line behavior -- corefiles vs. process ids.
2596 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2597 attaching to process NUMBER fails, GDB no longer attempts to open a
2598 core file named NUMBER. Attaching to a program using the -c option
2599 is no longer supported. Instead, use the '-p' or '--pid' options.
2601 * GDB can now be built as a native debugger for debugging Windows x86
2602 (mingw32) Portable Executable (PE) programs.
2604 * Pending breakpoints no longer change their number when their address
2607 * GDB now supports breakpoints with multiple locations,
2608 including breakpoints on C++ constructors, inside C++ templates,
2609 and in inlined functions.
2611 * GDB's ability to debug optimized code has been improved. GDB more
2612 accurately identifies function bodies and lexical blocks that occupy
2613 more than one contiguous range of addresses.
2615 * Target descriptions can now describe registers for PowerPC.
2617 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2618 registers on PowerPC targets.
2620 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2621 targets even when the libthread_db library is not available.
2623 * The GDB remote stub, gdbserver, now supports the new file transfer
2624 commands (remote put, remote get, and remote delete).
2626 * The GDB remote stub, gdbserver, now supports run and attach in
2627 extended-remote mode.
2629 * hppa*64*-*-hpux11* target broken
2630 The debugger is unable to start a program and fails with the following
2631 error: "Error trying to get information about dynamic linker".
2632 The gdb-6.7 release is also affected.
2634 * GDB now supports the --enable-targets= configure option to allow
2635 building a single GDB executable that supports multiple remote
2636 target architectures.
2638 * GDB now supports debugging C and C++ programs which use the
2639 Decimal Floating Point extension. In addition, the PowerPC target
2640 now has a set of pseudo-registers to inspect decimal float values
2641 stored in two consecutive float registers.
2643 * The -break-insert MI command can optionally create pending
2646 * Improved support for debugging Ada
2647 Many improvements to the Ada language support have been made. These
2649 - Better support for Ada2005 interface types
2650 - Improved handling of arrays and slices in general
2651 - Better support for Taft-amendment types
2652 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2654 - Improved command completion in Ada
2657 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2662 set print frame-arguments (all|scalars|none)
2663 show print frame-arguments
2664 The value of this variable can be changed to control which argument
2665 values should be printed by the debugger when displaying a frame.
2670 Transfer files to and from a remote target, and delete remote files.
2677 Transfer files to and from a remote target, and delete remote files.
2679 * New remote packets
2686 Open, close, read, write, and delete files on the remote system.
2689 Attach to an existing process on the remote system, in extended-remote
2693 Run a new process on the remote system, in extended-remote mode.
2695 *** Changes in GDB 6.7
2697 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2698 bfd, libiberty and opcodes, as revealed by static analysis donated by
2699 Coverity, Inc. (http://scan.coverity.com).
2701 * When looking up multiply-defined global symbols, GDB will now prefer the
2702 symbol definition in the current shared library if it was built using the
2703 -Bsymbolic linker option.
2705 * When the Text User Interface (TUI) is not configured, GDB will now
2706 recognize the -tui command-line option and print a message that the TUI
2709 * The GDB remote stub, gdbserver, now has lower overhead for high
2710 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2712 * GDB for MIPS targets now autodetects whether a remote target provides
2713 32-bit or 64-bit register values.
2715 * Support for C++ member pointers has been improved.
2717 * GDB now understands XML target descriptions, which specify the
2718 target's overall architecture. GDB can read a description from
2719 a local file or over the remote serial protocol.
2721 * Vectors of single-byte data use a new integer type which is not
2722 automatically displayed as character or string data.
2724 * The /s format now works with the print command. It displays
2725 arrays of single-byte integers and pointers to single-byte integers
2728 * Target descriptions can now describe target-specific registers,
2729 for architectures which have implemented the support (currently
2730 only ARM, M68K, and MIPS).
2732 * GDB and the GDB remote stub, gdbserver, now support the XScale
2735 * The GDB remote stub, gdbserver, has been updated to support
2736 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2737 has been rewritten to use the standard GDB remote protocol.
2739 * GDB can now step into C++ functions which are called through thunks.
2741 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2743 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2744 layout. It also supports a TextSeg= and DataSeg= response when only
2745 segment base addresses (rather than offsets) are available.
2747 * The /i format now outputs any trailing branch delay slot instructions
2748 immediately following the last instruction within the count specified.
2750 * The GDB remote protocol "T" stop reply packet now supports a
2751 "library" response. Combined with the new "qXfer:libraries:read"
2752 packet, this response allows GDB to debug shared libraries on targets
2753 where the operating system manages the list of loaded libraries (e.g.
2754 Windows and SymbianOS).
2756 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2757 (DLLs) on Windows and Windows CE targets.
2759 * GDB now supports a faster verification that a .debug file matches its binary
2760 according to its build-id signature, if the signature is present.
2766 Enable or disable hardware flow control (RTS/CTS) on the serial port
2767 when debugging using remote targets.
2769 set mem inaccessible-by-default
2770 show mem inaccessible-by-default
2771 If the target supplies a memory map, for instance via the remote
2772 protocol's "qXfer:memory-map:read" packet, setting this variable
2773 prevents GDB from accessing memory outside the memory map. This
2774 is useful for targets with memory mapped registers or which react
2775 badly to accesses of unmapped address space.
2777 set breakpoint auto-hw
2778 show breakpoint auto-hw
2779 If the target supplies a memory map, for instance via the remote
2780 protocol's "qXfer:memory-map:read" packet, setting this variable
2781 lets GDB use hardware breakpoints automatically for memory regions
2782 where it can not use software breakpoints. This covers both the
2783 "break" command and internal breakpoints used for other commands
2784 including "next" and "finish".
2787 catch exception unhandled
2788 Stop the program execution when Ada exceptions are raised.
2791 Stop the program execution when an Ada assertion failed.
2795 Set an alternate system root for target files. This is a more
2796 general version of "set solib-absolute-prefix", which is now
2797 an alias to "set sysroot".
2800 Provide extended SPU facility status information. This set of
2801 commands is available only when debugging the Cell/B.E. SPU
2804 * New native configurations
2806 OpenBSD/sh sh*-*openbsd*
2809 unset tdesc filename
2811 Use the specified local file as an XML target description, and do
2812 not query the target for its built-in description.
2816 OpenBSD/sh sh*-*-openbsd*
2817 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2818 Toshiba Media Processor mep-elf
2820 * New remote packets
2823 Ignore the specified signals; pass them directly to the debugged program
2824 without stopping other threads or reporting them to GDB.
2826 qXfer:features:read:
2827 Read an XML target description from the target, which describes its
2832 Read or write contents of an spufs file on the target system. These
2833 packets are available only on the Cell/B.E. SPU architecture.
2835 qXfer:libraries:read:
2836 Report the loaded shared libraries. Combined with new "T" packet
2837 response, this packet allows GDB to debug shared libraries on
2838 targets where the operating system manages the list of loaded
2839 libraries (e.g. Windows and SymbianOS).
2843 Support for these obsolete configurations has been removed.
2851 i[34567]86-*-lynxos*
2852 i[34567]86-*-netware*
2853 i[34567]86-*-sco3.2v5*
2854 i[34567]86-*-sco3.2v4*
2856 i[34567]86-*-sysv4.2*
2859 i[34567]86-*-unixware2*
2860 i[34567]86-*-unixware*
2869 * Other removed features
2876 Various m68k-only ROM monitors.
2883 Various Renesas ROM monitors and debugging interfaces for SH and
2888 Support for a Macraigor serial interface to on-chip debugging.
2889 GDB does not directly support the newer parallel or USB
2894 A debug information format. The predecessor to DWARF 2 and
2895 DWARF 3, which are still supported.
2897 Support for the HP aCC compiler on HP-UX/PA-RISC
2899 SOM-encapsulated symbolic debugging information, automatic
2900 invocation of pxdb, and the aCC custom C++ ABI. This does not
2901 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2902 with aCC can still be debugged on an assembly level.
2904 MIPS ".pdr" sections
2906 A MIPS-specific format used to describe stack frame layout
2907 in debugging information.
2911 GDB could work with an older version of Guile to debug
2912 the interpreter and Scheme programs running in it.
2914 set mips stack-arg-size
2915 set mips saved-gpreg-size
2917 Use "set mips abi" to control parameter passing for MIPS.
2919 *** Changes in GDB 6.6
2924 Cell Broadband Engine SPU spu-elf
2926 * GDB can now be configured as a cross-debugger targeting native Windows
2927 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2928 running on a Windows system over TCP/IP to debug Windows programs.
2930 * The GDB remote stub, gdbserver, has been updated to support Windows and
2931 Cygwin debugging. Both single-threaded and multi-threaded programs are
2934 * The "set trust-readonly-sections" command works again. This command was
2935 broken in GDB 6.3, 6.4, and 6.5.
2937 * The "load" command now supports writing to flash memory, if the remote
2938 stub provides the required support.
2940 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2941 longer requires symbolic debug information (e.g. DWARF-2).
2946 unset substitute-path
2947 show substitute-path
2948 Manage a list of substitution rules that GDB uses to rewrite the name
2949 of the directories where the sources are located. This can be useful
2950 for instance when the sources were moved to a different location
2951 between compilation and debugging.
2955 Print each CLI command as it is executed. Each command is prefixed with
2956 a number of `+' symbols representing the nesting depth.
2957 The source command now has a `-v' option to enable the same feature.
2961 The ARM Demon monitor support (RDP protocol, "target rdp").
2963 Kernel Object Display, an embedded debugging feature which only worked with
2964 an obsolete version of Cisco IOS.
2966 The 'set download-write-size' and 'show download-write-size' commands.
2968 * New remote packets
2971 Tell a stub about GDB client features, and request remote target features.
2972 The first feature implemented is PacketSize, which allows the target to
2973 specify the size of packets it can handle - to minimize the number of
2974 packets required and improve performance when connected to a remote
2978 Fetch an OS auxilliary vector from the remote stub. This packet is a
2979 more efficient replacement for qPart:auxv:read.
2981 qXfer:memory-map:read:
2982 Fetch a memory map from the remote stub, including information about
2983 RAM, ROM, and flash memory devices.
2988 Erase and program a flash memory device.
2990 * Removed remote packets
2993 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2994 used it, and only gdbserver implemented it.
2996 *** Changes in GDB 6.5
3000 Renesas M32C/M16C m32c-elf
3002 Morpho Technologies ms1 ms1-elf
3006 init-if-undefined Initialize a convenience variable, but
3007 only if it doesn't already have a value.
3009 The following commands are presently only implemented for native GNU/Linux:
3011 checkpoint Save a snapshot of the program state.
3013 restart <n> Return the program state to a
3014 previously saved state.
3016 info checkpoints List currently saved checkpoints.
3018 delete-checkpoint <n> Delete a previously saved checkpoint.
3020 set|show detach-on-fork Tell gdb whether to detach from a newly
3021 forked process, or to keep debugging it.
3023 info forks List forks of the user program that
3024 are available to be debugged.
3026 fork <n> Switch to debugging one of several
3027 forks of the user program that are
3028 available to be debugged.
3030 delete-fork <n> Delete a fork from the list of forks
3031 that are available to be debugged (and
3032 kill the forked process).
3034 detach-fork <n> Delete a fork from the list of forks
3035 that are available to be debugged (and
3036 allow the process to continue).
3040 Morpho Technologies ms2 ms1-elf
3042 * Improved Windows host support
3044 GDB now builds as a cross debugger hosted on i686-mingw32, including
3045 native console support, and remote communications using either
3046 network sockets or serial ports.
3048 * Improved Modula-2 language support
3050 GDB can now print most types in the Modula-2 syntax. This includes:
3051 basic types, set types, record types, enumerated types, range types,
3052 pointer types and ARRAY types. Procedure var parameters are correctly
3053 printed and hexadecimal addresses and character constants are also
3054 written in the Modula-2 syntax. Best results can be obtained by using
3055 GNU Modula-2 together with the -gdwarf-2 command line option.
3059 The ARM rdi-share module.
3061 The Netware NLM debug server.
3063 *** Changes in GDB 6.4
3065 * New native configurations
3067 OpenBSD/arm arm*-*-openbsd*
3068 OpenBSD/mips64 mips64-*-openbsd*
3072 Morpho Technologies ms1 ms1-elf
3074 * New command line options
3076 --batch-silent As for --batch, but totally silent.
3077 --return-child-result The debugger will exist with the same value
3078 the child (debugged) program exited with.
3079 --eval-command COMMAND, -ex COMMAND
3080 Execute a single GDB CLI command. This may be
3081 specified multiple times and in conjunction
3082 with the --command (-x) option.
3084 * Deprecated commands removed
3086 The following commands, that were deprecated in 2000, have been
3090 set|show arm disassembly-flavor set|show arm disassembler
3091 othernames set arm disassembler
3092 set|show remotedebug set|show debug remote
3093 set|show archdebug set|show debug arch
3094 set|show eventdebug set|show debug event
3097 * New BSD user-level threads support
3099 It is now possible to debug programs using the user-level threads
3100 library on OpenBSD and FreeBSD. Currently supported (target)
3103 FreeBSD/amd64 x86_64-*-freebsd*
3104 FreeBSD/i386 i386-*-freebsd*
3105 OpenBSD/i386 i386-*-openbsd*
3107 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3108 are not yet supported.
3110 * New support for Matsushita MN10300 w/sim added
3111 (Work in progress). mn10300-elf.
3113 * REMOVED configurations and files
3115 VxWorks and the XDR protocol *-*-vxworks
3116 Motorola MCORE mcore-*-*
3117 National Semiconductor NS32000 ns32k-*-*
3119 * New "set print array-indexes" command
3121 After turning this setting "on", GDB prints the index of each element
3122 when displaying arrays. The default is "off" to preserve the previous
3125 * VAX floating point support
3127 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3129 * User-defined command support
3131 In addition to using $arg0..$arg9 for argument passing, it is now possible
3132 to use $argc to determine now many arguments have been passed. See the
3133 section on user-defined commands in the user manual for more information.
3135 *** Changes in GDB 6.3:
3137 * New command line option
3139 GDB now accepts -l followed by a number to set the timeout for remote
3142 * GDB works with GCC -feliminate-dwarf2-dups
3144 GDB now supports a more compact representation of DWARF-2 debug
3145 information using DW_FORM_ref_addr references. These are produced
3146 by GCC with the option -feliminate-dwarf2-dups and also by some
3147 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3148 to use -feliminate-dwarf2-dups.
3150 * Internationalization
3152 When supported by the host system, GDB will be built with
3153 internationalization (libintl). The task of marking up the sources is
3154 continued, we're looking forward to our first translation.
3158 Initial support for debugging programs compiled with the GNAT
3159 implementation of the Ada programming language has been integrated
3160 into GDB. In this release, support is limited to expression evaluation.
3162 * New native configurations
3164 GNU/Linux/m32r m32r-*-linux-gnu
3168 GDB's remote protocol now includes support for the 'p' packet. This
3169 packet is used to fetch individual registers from a remote inferior.
3171 * END-OF-LIFE registers[] compatibility module
3173 GDB's internal register infrastructure has been completely rewritten.
3174 The new infrastructure making possible the implementation of key new
3175 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3178 GDB 6.3 will be the last release to include the the registers[]
3179 compatibility module that allowed out-of-date configurations to
3180 continue to work. This change directly impacts the following
3190 powerpc bdm protocol
3192 Unless there is activity to revive these configurations, they will be
3193 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3195 * OBSOLETE configurations and files
3197 Configurations that have been declared obsolete in this release have
3198 been commented out. Unless there is activity to revive these
3199 configurations, the next release of GDB will have their sources
3200 permanently REMOVED.
3209 *** Changes in GDB 6.2.1:
3211 * MIPS `break main; run' gave an heuristic-fence-post warning
3213 When attempting to run even a simple program, a warning about
3214 heuristic-fence-post being hit would be reported. This problem has
3217 * MIPS IRIX 'long double' crashed GDB
3219 When examining a long double variable, GDB would get a segmentation
3220 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3221 IRIX long double values).
3225 A bug in the VAX stack code was causing problems with the "next"
3226 command. This problem has been fixed.
3228 *** Changes in GDB 6.2:
3230 * Fix for ``many threads''
3232 On GNU/Linux systems that use the NPTL threads library, a program
3233 rapidly creating and deleting threads would confuse GDB leading to the
3236 ptrace: No such process.
3237 thread_db_get_info: cannot get thread info: generic error
3239 This problem has been fixed.
3241 * "-async" and "-noasync" options removed.
3243 Support for the broken "-noasync" option has been removed (it caused
3246 * New ``start'' command.
3248 This command runs the program until the begining of the main procedure.
3250 * New BSD Kernel Data Access Library (libkvm) interface
3252 Using ``target kvm'' it is now possible to debug kernel core dumps and
3253 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3254 platforms. Currently supported (native-only) configurations are:
3256 FreeBSD/amd64 x86_64-*-freebsd*
3257 FreeBSD/i386 i?86-*-freebsd*
3258 NetBSD/i386 i?86-*-netbsd*
3259 NetBSD/m68k m68*-*-netbsd*
3260 NetBSD/sparc sparc-*-netbsd*
3261 OpenBSD/amd64 x86_64-*-openbsd*
3262 OpenBSD/i386 i?86-*-openbsd*
3263 OpenBSD/m68k m68*-openbsd*
3264 OpenBSD/sparc sparc-*-openbsd*
3266 * Signal trampoline code overhauled
3268 Many generic problems with GDB's signal handling code have been fixed.
3269 These include: backtraces through non-contiguous stacks; recognition
3270 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3271 call; backtrace through a signal trampoline; step into and out of
3272 signal handlers; and single-stepping in the signal trampoline.
3274 Please note that kernel bugs are a limiting factor here. These
3275 features have been shown to work on an s390 GNU/Linux system that
3276 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3278 * Cygwin support for DWARF 2 added.
3280 * New native configurations
3282 GNU/Linux/hppa hppa*-*-linux*
3283 OpenBSD/hppa hppa*-*-openbsd*
3284 OpenBSD/m68k m68*-*-openbsd*
3285 OpenBSD/m88k m88*-*-openbsd*
3286 OpenBSD/powerpc powerpc-*-openbsd*
3287 NetBSD/vax vax-*-netbsd*
3288 OpenBSD/vax vax-*-openbsd*
3290 * END-OF-LIFE frame compatibility module
3292 GDB's internal frame infrastructure has been completely rewritten.
3293 The new infrastructure making it possible to support key new features
3294 including DWARF 2 Call Frame Information. To aid in the task of
3295 migrating old configurations to this new infrastructure, a
3296 compatibility module, that allowed old configurations to continue to
3297 work, was also included.
3299 GDB 6.2 will be the last release to include this frame compatibility
3300 module. This change directly impacts the following configurations:
3310 Unless there is activity to revive these configurations, they will be
3311 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3313 * REMOVED configurations and files
3315 Sun 3, running SunOS 3 m68*-*-sunos3*
3316 Sun 3, running SunOS 4 m68*-*-sunos4*
3317 Sun 2, running SunOS 3 m68000-*-sunos3*
3318 Sun 2, running SunOS 4 m68000-*-sunos4*
3319 Motorola 680x0 running LynxOS m68*-*-lynxos*
3320 AT&T 3b1/Unix pc m68*-att-*
3321 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3322 decstation mips-dec-* mips-little-*
3323 riscos mips-*-riscos* mips-*-sysv*
3324 sonymips mips-sony-*
3325 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3327 *** Changes in GDB 6.1.1:
3329 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3331 The TUI (Text-mode User Interface) is now built as part of a default
3332 GDB configuration. It is enabled by either selecting the TUI with the
3333 command line option "-i=tui" or by running the separate "gdbtui"
3334 program. For more information on the TUI, see the manual "Debugging
3337 * Pending breakpoint support (also included in GDB 6.1)
3339 Support has been added to allow you to specify breakpoints in shared
3340 libraries that have not yet been loaded. If a breakpoint location
3341 cannot be found, and the "breakpoint pending" option is set to auto,
3342 GDB queries you if you wish to make the breakpoint pending on a future
3343 shared-library load. If and when GDB resolves the breakpoint symbol,
3344 the pending breakpoint is removed as one or more regular breakpoints
3347 Pending breakpoints are very useful for GCJ Java debugging.
3349 * Fixed ISO-C build problems
3351 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3352 non ISO-C code that stopped them being built using a more strict ISO-C
3353 compiler (e.g., IBM's C compiler).
3355 * Fixed build problem on IRIX 5
3357 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3358 wasn't able to compile compile on an IRIX 5 system.
3360 * Added execute permission to gdb/gdbserver/configure
3362 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3363 permission. This bug would cause configure to fail on a number of
3364 systems (Solaris, IRIX). Ref: server/519.
3366 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3368 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3369 has been updated to use constant array sizes.
3371 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3373 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3374 its generated DWARF Call Frame Info. This encoding was causing GDB to
3375 panic, that panic has been fixed. Ref: gdb/1628.
3377 * Fixed a problem when examining parameters in shared library code.
3379 When examining parameters in optimized shared library code generated
3380 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3381 not available''. GDB now correctly displays the variable's value.
3383 *** Changes in GDB 6.1:
3385 * Removed --with-mmalloc
3387 Support for the mmalloc memory manager has been removed, as it
3388 conflicted with the internal gdb byte cache.
3390 * Changes in AMD64 configurations
3392 The AMD64 target now includes the %cs and %ss registers. As a result
3393 the AMD64 remote protocol has changed; this affects the floating-point
3394 and SSE registers. If you rely on those registers for your debugging,
3395 you should upgrade gdbserver on the remote side.
3397 * Revised SPARC target
3399 The SPARC target has been completely revised, incorporating the
3400 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3401 support for LynxOS and SunOS 4 has been dropped. Calling functions
3402 from within GDB on operating systems with a non-executable stack
3403 (Solaris, OpenBSD) now works.
3407 GDB has a new C++ demangler which does a better job on the mangled
3408 names generated by current versions of g++. It also runs faster, so
3409 with this and other changes gdb should now start faster on large C++
3412 * DWARF 2 Location Expressions
3414 GDB support for location expressions has been extended to support function
3415 arguments and frame bases. Older versions of GDB could crash when they
3418 * C++ nested types and namespaces
3420 GDB's support for nested types and namespaces in C++ has been
3421 improved, especially if you use the DWARF 2 debugging format. (This
3422 is the default for recent versions of GCC on most platforms.)
3423 Specifically, if you have a class "Inner" defined within a class or
3424 namespace "Outer", then GDB realizes that the class's name is
3425 "Outer::Inner", not simply "Inner". This should greatly reduce the
3426 frequency of complaints about not finding RTTI symbols. In addition,
3427 if you are stopped at inside of a function defined within a namespace,
3428 GDB modifies its name lookup accordingly.
3430 * New native configurations
3432 NetBSD/amd64 x86_64-*-netbsd*
3433 OpenBSD/amd64 x86_64-*-openbsd*
3434 OpenBSD/alpha alpha*-*-openbsd*
3435 OpenBSD/sparc sparc-*-openbsd*
3436 OpenBSD/sparc64 sparc64-*-openbsd*
3438 * New debugging protocols
3440 M32R with SDI protocol m32r-*-elf*
3442 * "set prompt-escape-char" command deleted.
3444 The command "set prompt-escape-char" has been deleted. This command,
3445 and its very obscure effet on GDB's prompt, was never documented,
3446 tested, nor mentioned in the NEWS file.
3448 * OBSOLETE configurations and files
3450 Configurations that have been declared obsolete in this release have
3451 been commented out. Unless there is activity to revive these
3452 configurations, the next release of GDB will have their sources
3453 permanently REMOVED.
3455 Sun 3, running SunOS 3 m68*-*-sunos3*
3456 Sun 3, running SunOS 4 m68*-*-sunos4*
3457 Sun 2, running SunOS 3 m68000-*-sunos3*
3458 Sun 2, running SunOS 4 m68000-*-sunos4*
3459 Motorola 680x0 running LynxOS m68*-*-lynxos*
3460 AT&T 3b1/Unix pc m68*-att-*
3461 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3462 decstation mips-dec-* mips-little-*
3463 riscos mips-*-riscos* mips-*-sysv*
3464 sonymips mips-sony-*
3465 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3467 * REMOVED configurations and files
3469 SGI Irix-4.x mips-sgi-irix4 or iris4
3470 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3471 Z8000 simulator z8k-zilog-none or z8ksim
3472 Matsushita MN10200 w/simulator mn10200-*-*
3473 H8/500 simulator h8500-hitachi-hms or h8500hms
3474 HP/PA running BSD hppa*-*-bsd*
3475 HP/PA running OSF/1 hppa*-*-osf*
3476 HP/PA Pro target hppa*-*-pro*
3477 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3478 386BSD i[3456]86-*-bsd*
3479 Sequent family i[3456]86-sequent-sysv4*
3480 i[3456]86-sequent-sysv*
3481 i[3456]86-sequent-bsd*
3482 SPARC running LynxOS sparc-*-lynxos*
3483 SPARC running SunOS 4 sparc-*-sunos4*
3484 Tsqware Sparclet sparclet-*-*
3485 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3487 *** Changes in GDB 6.0:
3491 Support for debugging the Objective-C programming language has been
3492 integrated into GDB.
3494 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3496 DWARF 2's Call Frame Information makes available compiler generated
3497 information that more exactly describes the program's run-time stack.
3498 By using this information, GDB is able to provide more robust stack
3501 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3502 have been updated to use a new backtrace mechanism which includes
3503 DWARF 2 CFI support.
3507 GDB's remote protocol has been extended to include support for hosted
3508 file I/O (where the remote target uses GDB's file system). See GDB's
3509 remote protocol documentation for details.
3511 * All targets using the new architecture framework.
3513 All of GDB's targets have been updated to use the new internal
3514 architecture framework. The way is now open for future GDB releases
3515 to include cross-architecture native debugging support (i386 on amd64,
3518 * GNU/Linux's Thread Local Storage (TLS)
3520 GDB now includes support for for the GNU/Linux implementation of
3521 per-thread variables.
3523 * GNU/Linux's Native POSIX Thread Library (NPTL)
3525 GDB's thread code has been updated to work with either the new
3526 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3528 * Separate debug info.
3530 GDB, in conjunction with BINUTILS, now supports a mechanism for
3531 automatically loading debug information from a separate file. Instead
3532 of shipping full debug and non-debug versions of system libraries,
3533 system integrators can now instead ship just the stripped libraries
3534 and optional debug files.
3536 * DWARF 2 Location Expressions
3538 DWARF 2 Location Expressions allow the compiler to more completely
3539 describe the location of variables (even in optimized code) to the
3542 GDB now includes preliminary support for location expressions (support
3543 for DW_OP_piece is still missing).
3547 A number of long standing bugs that caused GDB to die while starting a
3548 Java application have been fixed. GDB's Java support is now
3549 considered "useable".
3551 * GNU/Linux support for fork, vfork, and exec.
3553 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3554 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3557 * GDB supports logging output to a file
3559 There are two new commands, "set logging" and "show logging", which can be
3560 used to capture GDB's output to a file.
3562 * The meaning of "detach" has changed for gdbserver
3564 The "detach" command will now resume the application, as documented. To
3565 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3568 * d10v, m68hc11 `regs' command deprecated
3570 The `info registers' command has been updated so that it displays the
3571 registers using a format identical to the old `regs' command.
3575 A new command, "maint set profile on/off", has been added. This command can
3576 be used to enable or disable profiling while running GDB, to profile a
3577 session or a set of commands. In addition there is a new configure switch,
3578 "--enable-profiling", which will cause GDB to be compiled with profiling
3579 data, for more informative profiling results.
3581 * Default MI syntax changed to "mi2".
3583 The default MI (machine interface) syntax, enabled by the command line
3584 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3585 "mi1", can be enabled by specifying the option "-i=mi1".
3587 Support for the original "mi0" syntax (included in GDB 5.0) has been
3590 Fix for gdb/192: removed extraneous space when displaying frame level.
3591 Fix for gdb/672: update changelist is now output in mi list format.
3592 Fix for gdb/702: a -var-assign that updates the value now shows up
3593 in a subsequent -var-update.
3595 * New native configurations.
3597 FreeBSD/amd64 x86_64-*-freebsd*
3599 * Multi-arched targets.
3601 HP/PA HPUX11 hppa*-*-hpux*
3602 Renesas M32R/D w/simulator m32r-*-elf*
3604 * OBSOLETE configurations and files
3606 Configurations that have been declared obsolete in this release have
3607 been commented out. Unless there is activity to revive these
3608 configurations, the next release of GDB will have their sources
3609 permanently REMOVED.
3611 Z8000 simulator z8k-zilog-none or z8ksim
3612 Matsushita MN10200 w/simulator mn10200-*-*
3613 H8/500 simulator h8500-hitachi-hms or h8500hms
3614 HP/PA running BSD hppa*-*-bsd*
3615 HP/PA running OSF/1 hppa*-*-osf*
3616 HP/PA Pro target hppa*-*-pro*
3617 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3618 Sequent family i[3456]86-sequent-sysv4*
3619 i[3456]86-sequent-sysv*
3620 i[3456]86-sequent-bsd*
3621 Tsqware Sparclet sparclet-*-*
3622 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3624 * REMOVED configurations and files
3627 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3628 IBM AIX PS/2 i[3456]86-*-aix
3629 i386 running Mach 3.0 i[3456]86-*-mach3*
3630 i386 running Mach i[3456]86-*-mach*
3631 i386 running OSF/1 i[3456]86-*osf1mk*
3632 HP/Apollo 68k Family m68*-apollo*-sysv*,
3634 m68*-hp-bsd*, m68*-hp-hpux*
3635 Argonaut Risc Chip (ARC) arc-*-*
3636 Mitsubishi D30V d30v-*-*
3637 Fujitsu FR30 fr30-*-elf*
3638 OS/9000 i[34]86-*-os9k
3639 I960 with MON960 i960-*-coff
3641 * MIPS $fp behavior changed
3643 The convenience variable $fp, for the MIPS, now consistently returns
3644 the address of the current frame's base. Previously, depending on the
3645 context, $fp could refer to either $sp or the current frame's base
3646 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3647 The GNU Source-Level Debugger''.
3649 *** Changes in GDB 5.3:
3651 * GNU/Linux shared library multi-threaded performance improved.
3653 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3654 `/proc', in preference to `ptrace' for memory reads. This may result
3655 in an improvement in the start-up time of multi-threaded, shared
3656 library applications when run under GDB. One GDB user writes: ``loads
3657 shared libs like mad''.
3659 * ``gdbserver'' now supports multi-threaded applications on some targets
3661 Support for debugging multi-threaded applications which use
3662 the GNU/Linux LinuxThreads package has been added for
3663 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3664 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3666 * GDB now supports C/C++ preprocessor macros.
3668 GDB now expands preprocessor macro invocations in C/C++ expressions,
3669 and provides various commands for showing macro definitions and how
3672 The new command `macro expand EXPRESSION' expands any macro
3673 invocations in expression, and shows the result.
3675 The new command `show macro MACRO-NAME' shows the definition of the
3676 macro named MACRO-NAME, and where it was defined.
3678 Most compilers don't include information about macros in the debugging
3679 information by default. In GCC 3.1, for example, you need to compile
3680 your program with the options `-gdwarf-2 -g3'. If the macro
3681 information is present in the executable, GDB will read it.
3683 * Multi-arched targets.
3685 DEC Alpha (partial) alpha*-*-*
3686 DEC VAX (partial) vax-*-*
3688 National Semiconductor NS32000 (partial) ns32k-*-*
3689 Motorola 68000 (partial) m68k-*-*
3690 Motorola MCORE mcore-*-*
3694 Fujitsu FRV architecture added by Red Hat frv*-*-*
3697 * New native configurations
3699 Alpha NetBSD alpha*-*-netbsd*
3700 SH NetBSD sh*-*-netbsdelf*
3701 MIPS NetBSD mips*-*-netbsd*
3702 UltraSPARC NetBSD sparc64-*-netbsd*
3704 * OBSOLETE configurations and files
3706 Configurations that have been declared obsolete in this release have
3707 been commented out. Unless there is activity to revive these
3708 configurations, the next release of GDB will have their sources
3709 permanently REMOVED.
3711 Mitsubishi D30V d30v-*-*
3712 OS/9000 i[34]86-*-os9k
3713 IBM AIX PS/2 i[3456]86-*-aix
3714 Fujitsu FR30 fr30-*-elf*
3715 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3716 Argonaut Risc Chip (ARC) arc-*-*
3717 i386 running Mach 3.0 i[3456]86-*-mach3*
3718 i386 running Mach i[3456]86-*-mach*
3719 i386 running OSF/1 i[3456]86-*osf1mk*
3720 HP/Apollo 68k Family m68*-apollo*-sysv*,
3722 m68*-hp-bsd*, m68*-hp-hpux*
3723 I960 with MON960 i960-*-coff
3725 * OBSOLETE languages
3727 CHILL, a Pascal like language used by telecommunications companies.
3729 * REMOVED configurations and files
3731 AMD 29k family via UDI a29k-amd-udi, udi29k
3732 A29K VxWorks a29k-*-vxworks
3733 AMD 29000 embedded, using EBMON a29k-none-none
3734 AMD 29000 embedded with COFF a29k-none-coff
3735 AMD 29000 embedded with a.out a29k-none-aout
3737 testsuite/gdb.hp/gdb.threads-hp/ directory
3739 * New command "set max-user-call-depth <nnn>"
3741 This command allows the user to limit the call depth of user-defined
3742 commands. The default is 1024.
3744 * Changes in FreeBSD/i386 native debugging.
3746 Support for the "generate-core-file" has been added.
3748 * New commands "dump", "append", and "restore".
3750 These commands allow data to be copied from target memory
3751 to a bfd-format or binary file (dump and append), and back
3752 from a file into memory (restore).
3754 * Improved "next/step" support on multi-processor Alpha Tru64.
3756 The previous single-step mechanism could cause unpredictable problems,
3757 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3758 of a software single-step mechanism prevents this.
3760 *** Changes in GDB 5.2.1:
3768 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3769 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3770 Fix, by Joel Brobecker imported from mainline.
3772 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3773 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3774 Fix, by Fred Fish, imported from mainline.
3776 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3777 Surprisingly enough, it works now.
3778 By Michal Ludvig, imported from mainline.
3780 i386 hardware watchpoint support:
3781 avoid misses on second run for some targets.
3782 By Pierre Muller, imported from mainline.
3784 *** Changes in GDB 5.2:
3786 * New command "set trust-readonly-sections on[off]".
3788 This command is a hint that tells gdb that read-only sections
3789 really are read-only (ie. that their contents will not change).
3790 In this mode, gdb will go to the object file rather than the
3791 target to read memory from read-only sections (such as ".text").
3792 This can be a significant performance improvement on some
3793 (notably embedded) targets.
3795 * New command "generate-core-file" (or "gcore").
3797 This new gdb command allows the user to drop a core file of the child
3798 process state at any time. So far it's been implemented only for
3799 GNU/Linux and Solaris, but should be relatively easily ported to other
3800 hosts. Argument is core file name (defaults to core.<pid>).
3802 * New command line option
3804 GDB now accepts --pid or -p followed by a process id.
3806 * Change in command line behavior -- corefiles vs. process ids.
3808 There is a subtle behavior in the way in which GDB handles
3809 command line arguments. The first non-flag argument is always
3810 a program to debug, but the second non-flag argument may either
3811 be a corefile or a process id. Previously, GDB would attempt to
3812 open the second argument as a corefile, and if that failed, would
3813 issue a superfluous error message and then attempt to attach it as
3814 a process. Now, if the second argument begins with a non-digit,
3815 it will be treated as a corefile. If it begins with a digit,
3816 GDB will attempt to attach it as a process, and if no such process
3817 is found, will then attempt to open it as a corefile.
3819 * Changes in ARM configurations.
3821 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3822 configuration is fully multi-arch.
3824 * New native configurations
3826 ARM NetBSD arm*-*-netbsd*
3827 x86 OpenBSD i[3456]86-*-openbsd*
3828 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3829 Sparc64 running FreeBSD sparc64-*-freebsd*
3833 Sanyo XStormy16 xstormy16-elf
3835 * OBSOLETE configurations and files
3837 Configurations that have been declared obsolete in this release have
3838 been commented out. Unless there is activity to revive these
3839 configurations, the next release of GDB will have their sources
3840 permanently REMOVED.
3842 AMD 29k family via UDI a29k-amd-udi, udi29k
3843 A29K VxWorks a29k-*-vxworks
3844 AMD 29000 embedded, using EBMON a29k-none-none
3845 AMD 29000 embedded with COFF a29k-none-coff
3846 AMD 29000 embedded with a.out a29k-none-aout
3848 testsuite/gdb.hp/gdb.threads-hp/ directory
3850 * REMOVED configurations and files
3852 TI TMS320C80 tic80-*-*
3854 PowerPC Solaris powerpcle-*-solaris*
3855 PowerPC Windows NT powerpcle-*-cygwin32
3856 PowerPC Netware powerpc-*-netware*
3857 Harris/CXUX m88k m88*-harris-cxux*
3858 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3859 ns32k-utek-sysv* ns32k-utek-*
3860 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3861 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3862 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3863 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3864 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3866 * Changes to command line processing
3868 The new `--args' feature can be used to specify command-line arguments
3869 for the inferior from gdb's command line.
3871 * Changes to key bindings
3873 There is a new `operate-and-get-next' function bound to `C-o'.
3875 *** Changes in GDB 5.1.1
3877 Fix compile problem on DJGPP.
3879 Fix a problem with floating-point registers on the i386 being
3882 Fix to stop GDB crashing on .debug_str debug info.
3884 Numerous documentation fixes.
3886 Numerous testsuite fixes.
3888 *** Changes in GDB 5.1:
3890 * New native configurations
3892 Alpha FreeBSD alpha*-*-freebsd*
3893 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3894 MIPS GNU/Linux mips*-*-linux*
3895 MIPS SGI Irix 6.x mips*-sgi-irix6*
3896 ia64 AIX ia64-*-aix*
3897 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3901 Motorola 68HC11 and 68HC12 m68hc11-elf
3903 UltraSparc running GNU/Linux sparc64-*-linux*
3905 * OBSOLETE configurations and files
3907 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3908 Harris/CXUX m88k m88*-harris-cxux*
3909 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3910 ns32k-utek-sysv* ns32k-utek-*
3911 TI TMS320C80 tic80-*-*
3913 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3914 PowerPC Solaris powerpcle-*-solaris*
3915 PowerPC Windows NT powerpcle-*-cygwin32
3916 PowerPC Netware powerpc-*-netware*
3917 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3918 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3919 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3920 Apple Macintosh (MPW) host N/A
3922 stuff.c (Program to stuff files into a specially prepared space in kdb)
3923 kdb-start.c (Main loop for the standalone kernel debugger)
3925 Configurations that have been declared obsolete in this release have
3926 been commented out. Unless there is activity to revive these
3927 configurations, the next release of GDB will have their sources
3928 permanently REMOVED.
3930 * REMOVED configurations and files
3932 Altos 3068 m68*-altos-*
3933 Convex c1-*-*, c2-*-*
3935 ARM RISCix arm-*-* (as host)
3939 * GDB has been converted to ISO C.
3941 GDB's source code has been converted to ISO C. In particular, the
3942 sources are fully protoized, and rely on standard headers being
3947 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3949 * The MI enabled by default.
3951 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3952 revised and enabled by default. Packages which use GDB as a debugging
3953 engine behind a UI or another front end are encouraged to switch to
3954 using the GDB/MI interface, instead of the old annotations interface
3955 which is now deprecated.
3957 * Support for debugging Pascal programs.
3959 GDB now includes support for debugging Pascal programs. The following
3960 main features are supported:
3962 - Pascal-specific data types such as sets;
3964 - automatic recognition of Pascal sources based on file-name
3967 - Pascal-style display of data types, variables, and functions;
3969 - a Pascal expression parser.
3971 However, some important features are not yet supported.
3973 - Pascal string operations are not supported at all;
3975 - there are some problems with boolean types;
3977 - Pascal type hexadecimal constants are not supported
3978 because they conflict with the internal variables format;
3980 - support for Pascal objects and classes is not full yet;
3982 - unlike Pascal, GDB is case-sensitive for symbol names.
3984 * Changes in completion.
3986 Commands such as `shell', `run' and `set args', which pass arguments
3987 to inferior programs, now complete on file names, similar to what
3988 users expect at the shell prompt.
3990 Commands which accept locations, such as `disassemble', `print',
3991 `breakpoint', `until', etc. now complete on filenames as well as
3992 program symbols. Thus, if you type "break foob TAB", and the source
3993 files linked into the programs include `foobar.c', that file name will
3994 be one of the candidates for completion. However, file names are not
3995 considered for completion after you typed a colon that delimits a file
3996 name from a name of a function in that file, as in "break foo.c:bar".
3998 `set demangle-style' completes on available demangling styles.
4000 * New platform-independent commands:
4002 It is now possible to define a post-hook for a command as well as a
4003 hook that runs before the command. For more details, see the
4004 documentation of `hookpost' in the GDB manual.
4006 * Changes in GNU/Linux native debugging.
4008 Support for debugging multi-threaded programs has been completely
4009 revised for all platforms except m68k and sparc. You can now debug as
4010 many threads as your system allows you to have.
4012 Attach/detach is supported for multi-threaded programs.
4014 Support for SSE registers was added for x86. This doesn't work for
4015 multi-threaded programs though.
4017 * Changes in MIPS configurations.
4019 Multi-arch support is enabled for all MIPS configurations.
4021 GDB can now be built as native debugger on SGI Irix 6.x systems for
4022 debugging n32 executables. (Debugging 64-bit executables is not yet
4025 * Unified support for hardware watchpoints in all x86 configurations.
4027 Most (if not all) native x86 configurations support hardware-assisted
4028 breakpoints and watchpoints in a unified manner. This support
4029 implements debug register sharing between watchpoints, which allows to
4030 put a virtually infinite number of watchpoints on the same address,
4031 and also supports watching regions up to 16 bytes with several debug
4034 The new maintenance command `maintenance show-debug-regs' toggles
4035 debugging print-outs in functions that insert, remove, and test
4036 watchpoints and hardware breakpoints.
4038 * Changes in the DJGPP native configuration.
4040 New command ``info dos sysinfo'' displays assorted information about
4041 the CPU, OS, memory, and DPMI server.
4043 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4044 display information about segment descriptors stored in GDT, LDT, and
4047 New commands ``info dos pde'' and ``info dos pte'' display entries
4048 from Page Directory and Page Tables (for now works with CWSDPMI only).
4049 New command ``info dos address-pte'' displays the Page Table entry for
4050 a given linear address.
4052 GDB can now pass command lines longer than 126 characters to the
4053 program being debugged (requires an update to the libdbg.a library
4054 which is part of the DJGPP development kit).
4056 DWARF2 debug info is now supported.
4058 It is now possible to `step' and `next' through calls to `longjmp'.
4060 * Changes in documentation.
4062 All GDB documentation was converted to GFDL, the GNU Free
4063 Documentation License.
4065 Tracepoints-related commands are now fully documented in the GDB
4068 TUI, the Text-mode User Interface, is now documented in the manual.
4070 Tracepoints-related commands are now fully documented in the GDB
4073 The "GDB Internals" manual now has an index. It also includes
4074 documentation of `ui_out' functions, GDB coding standards, x86
4075 hardware watchpoints, and memory region attributes.
4077 * GDB's version number moved to ``version.in''
4079 The Makefile variable VERSION has been replaced by the file
4080 ``version.in''. People creating GDB distributions should update the
4081 contents of this file.
4085 GUD support is now a standard part of the EMACS distribution.
4087 *** Changes in GDB 5.0:
4089 * Improved support for debugging FP programs on x86 targets
4091 Unified and much-improved support for debugging floating-point
4092 programs on all x86 targets. In particular, ``info float'' now
4093 displays the FP registers in the same format on all x86 targets, with
4094 greater level of detail.
4096 * Improvements and bugfixes in hardware-assisted watchpoints
4098 It is now possible to watch array elements, struct members, and
4099 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4100 on x86 targets no longer erroneously trigger when the address is
4103 * Improvements in the native DJGPP version of GDB
4105 The distribution now includes all the scripts and auxiliary files
4106 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4107 machines ``out of the box''.
4109 The DJGPP version can now debug programs that use signals. It is
4110 possible to catch signals that happened in the debuggee, deliver
4111 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4112 would kill the program being debugged.) Programs that hook hardware
4113 interrupts (keyboard, timer, etc.) can also be debugged.
4115 It is now possible to debug DJGPP programs that redirect their
4116 standard handles or switch them to raw (as opposed to cooked) mode, or
4117 even close them. The command ``run < foo > bar'' works as expected,
4118 and ``info terminal'' reports useful information about the debuggee's
4119 terminal, including raw/cooked mode, redirection, etc.
4121 The DJGPP version now uses termios functions for console I/O, which
4122 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4125 DOS-style file names with drive letters are now fully supported by
4128 It is now possible to debug DJGPP programs that switch their working
4129 directory. It is also possible to rerun the debuggee any number of
4130 times without restarting GDB; thus, you can use the same setup,
4131 breakpoints, etc. for many debugging sessions.
4133 * New native configurations
4135 ARM GNU/Linux arm*-*-linux*
4136 PowerPC GNU/Linux powerpc-*-linux*
4140 Motorola MCore mcore-*-*
4141 x86 VxWorks i[3456]86-*-vxworks*
4142 PowerPC VxWorks powerpc-*-vxworks*
4143 TI TMS320C80 tic80-*-*
4145 * OBSOLETE configurations
4147 Altos 3068 m68*-altos-*
4148 Convex c1-*-*, c2-*-*
4150 ARM RISCix arm-*-* (as host)
4153 Configurations that have been declared obsolete will be commented out,
4154 but the code will be left in place. If there is no activity to revive
4155 these configurations before the next release of GDB, the sources will
4156 be permanently REMOVED.
4158 * Gould support removed
4160 Support for the Gould PowerNode and NP1 has been removed.
4162 * New features for SVR4
4164 On SVR4 native platforms (such as Solaris), if you attach to a process
4165 without first loading a symbol file, GDB will now attempt to locate and
4166 load symbols from the running process's executable file.
4168 * Many C++ enhancements
4170 C++ support has been greatly improved. Overload resolution now works properly
4171 in almost all cases. RTTI support is on the way.
4173 * Remote targets can connect to a sub-program
4175 A popen(3) style serial-device has been added. This device starts a
4176 sub-process (such as a stand-alone simulator) and then communicates
4177 with that. The sub-program to run is specified using the syntax
4178 ``|<program> <args>'' vis:
4180 (gdb) set remotedebug 1
4181 (gdb) target extended-remote |mn10300-elf-sim program-args
4183 * MIPS 64 remote protocol
4185 A long standing bug in the mips64 remote protocol where by GDB
4186 expected certain 32 bit registers (ex SR) to be transfered as 32
4187 instead of 64 bits has been fixed.
4189 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4190 added to provide backward compatibility with older versions of GDB.
4192 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4194 The command ``set remotebinarydownload'' command has been replaced by
4195 ``set remote X-packet''. Other commands in ``set remote'' family
4196 include ``set remote P-packet''.
4198 * Breakpoint commands accept ranges.
4200 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4201 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4202 ``tracepoint passcount'' also accepts a range of tracepoints.
4204 * ``apropos'' command added.
4206 The ``apropos'' command searches through command names and
4207 documentation strings, printing out matches, making it much easier to
4208 try to find a command that does what you are looking for.
4212 A new machine oriented interface (MI) has been added to GDB. This
4213 interface is designed for debug environments running GDB as a separate
4214 process. This is part of the long term libGDB project. See the
4215 "GDB/MI" chapter of the GDB manual for further information. It can be
4216 enabled by configuring with:
4218 .../configure --enable-gdbmi
4220 *** Changes in GDB-4.18:
4222 * New native configurations
4224 HP-UX 10.20 hppa*-*-hpux10.20
4225 HP-UX 11.x hppa*-*-hpux11.0*
4226 M68K GNU/Linux m68*-*-linux*
4230 Fujitsu FR30 fr30-*-elf*
4231 Intel StrongARM strongarm-*-*
4232 Mitsubishi D30V d30v-*-*
4234 * OBSOLETE configurations
4236 Gould PowerNode, NP1 np1-*-*, pn-*-*
4238 Configurations that have been declared obsolete will be commented out,
4239 but the code will be left in place. If there is no activity to revive
4240 these configurations before the next release of GDB, the sources will
4241 be permanently REMOVED.
4245 As a compatibility experiment, GDB's source files buildsym.h and
4246 buildsym.c have been converted to pure standard C, no longer
4247 containing any K&R compatibility code. We believe that all systems in
4248 use today either come with a standard C compiler, or have a GCC port
4249 available. If this is not true, please report the affected
4250 configuration to bug-gdb@gnu.org immediately. See the README file for
4251 information about getting a standard C compiler if you don't have one
4256 GDB now uses readline 2.2.
4258 * set extension-language
4260 You can now control the mapping between filename extensions and source
4261 languages by using the `set extension-language' command. For instance,
4262 you can ask GDB to treat .c files as C++ by saying
4263 set extension-language .c c++
4264 The command `info extensions' lists all of the recognized extensions
4265 and their associated languages.
4267 * Setting processor type for PowerPC and RS/6000
4269 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4270 you can use the `set processor' command to specify what variant of the
4271 PowerPC family you are debugging. The command
4275 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4276 following PowerPC and RS6000 variants:
4278 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4279 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4281 403GC IBM PowerPC 403GC
4282 505 Motorola PowerPC 505
4283 860 Motorola PowerPC 860 or 850
4284 601 Motorola PowerPC 601
4285 602 Motorola PowerPC 602
4286 603 Motorola/IBM PowerPC 603 or 603e
4287 604 Motorola PowerPC 604 or 604e
4288 750 Motorola/IBM PowerPC 750 or 750
4290 At the moment, this command just tells GDB what to name the
4291 special-purpose processor registers. Since almost all the affected
4292 registers are inaccessible to user-level programs, this command is
4293 only useful for remote debugging in its present form.
4297 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4298 more extensive support for HP-UX. Added features include shared
4299 library support, kernel threads and hardware watchpoints for 11.00,
4300 support for HP's ANSI C and C++ compilers, and a compatibility mode
4301 for xdb and dbx commands.
4305 HP's donation includes the new concept of catchpoints, which is a
4306 generalization of the old catch command. On HP-UX, it is now possible
4307 to catch exec, fork, and vfork, as well as library loading.
4309 This means that the existing catch command has changed; its first
4310 argument now specifies the type of catch to be set up. See the
4311 output of "help catch" for a list of catchpoint types.
4313 * Debugging across forks
4315 On HP-UX, you can choose which process to debug when a fork() happens
4320 HP has donated a curses-based terminal user interface (TUI). To get
4321 it, build with --enable-tui. Although this can be enabled for any
4322 configuration, at present it only works for native HP debugging.
4324 * GDB remote protocol additions
4326 A new protocol packet 'X' that writes binary data is now available.
4327 Default behavior is to try 'X', then drop back to 'M' if the stub
4328 fails to respond. The settable variable `remotebinarydownload'
4329 allows explicit control over the use of 'X'.
4331 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4332 full 64-bit address. The command
4334 set remoteaddresssize 32
4336 can be used to revert to the old behaviour. For existing remote stubs
4337 the change should not be noticed, as the additional address information
4340 In order to assist in debugging stubs, you may use the maintenance
4341 command `packet' to send any text string to the stub. For instance,
4343 maint packet heythere
4345 sends the packet "$heythere#<checksum>". Note that it is very easy to
4346 disrupt a debugging session by sending the wrong packet at the wrong
4349 The compare-sections command allows you to compare section data on the
4350 target to what is in the executable file without uploading or
4351 downloading, by comparing CRC checksums.
4353 * Tracing can collect general expressions
4355 You may now collect general expressions at tracepoints. This requires
4356 further additions to the target-side stub; see tracepoint.c and
4357 doc/agentexpr.texi for further details.
4359 * mask-address variable for Mips
4361 For Mips targets, you may control the zeroing of the upper 32 bits of
4362 a 64-bit address by entering `set mask-address on'. This is mainly
4363 of interest to users of embedded R4xxx and R5xxx processors.
4365 * Higher serial baud rates
4367 GDB's serial code now allows you to specify baud rates 57600, 115200,
4368 230400, and 460800 baud. (Note that your host system may not be able
4369 to achieve all of these rates.)
4373 The i960 configuration now includes an initial implementation of a
4374 builtin simulator, contributed by Jim Wilson.
4377 *** Changes in GDB-4.17:
4379 * New native configurations
4381 Alpha GNU/Linux alpha*-*-linux*
4382 Unixware 2.x i[3456]86-unixware2*
4383 Irix 6.x mips*-sgi-irix6*
4384 PowerPC GNU/Linux powerpc-*-linux*
4385 PowerPC Solaris powerpcle-*-solaris*
4386 Sparc GNU/Linux sparc-*-linux*
4387 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4391 Argonaut Risc Chip (ARC) arc-*-*
4392 Hitachi H8/300S h8300*-*-*
4393 Matsushita MN10200 w/simulator mn10200-*-*
4394 Matsushita MN10300 w/simulator mn10300-*-*
4395 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4396 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4397 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4398 Mitsubishi D10V w/simulator d10v-*-*
4399 Mitsubishi M32R/D w/simulator m32r-*-elf*
4400 Tsqware Sparclet sparclet-*-*
4401 NEC V850 w/simulator v850-*-*
4403 * New debugging protocols
4405 ARM with RDI protocol arm*-*-*
4406 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4407 DDB and LSI variants of PMON protocol mips*-*-*
4408 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4409 PowerPC with SDS protocol powerpc{,le}-*-eabi
4410 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4414 All configurations can now understand and use the DWARF 2 debugging
4415 format. The choice is automatic, if the symbol file contains DWARF 2
4420 GDB now includes basic Java language support. This support is
4421 only useful with Java compilers that produce native machine code.
4423 * solib-absolute-prefix and solib-search-path
4425 For SunOS and SVR4 shared libraries, you may now set the prefix for
4426 loading absolute shared library symbol files, and the search path for
4427 locating non-absolute shared library symbol files.
4429 * Live range splitting
4431 GDB can now effectively debug code for which GCC has performed live
4432 range splitting as part of its optimization. See gdb/doc/LRS for
4433 more details on the expected format of the stabs information.
4437 GDB's support for the GNU Hurd, including thread debugging, has been
4438 updated to work with current versions of the Hurd.
4442 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4443 instruction set. ARM GDB automatically detects when Thumb
4444 instructions are in use, and adjusts disassembly and backtracing
4449 GDB's MIPS target configurations now handle the MIP16 16-bit
4454 GDB now includes support for overlays; if an executable has been
4455 linked such that multiple sections are based at the same address, GDB
4456 will decide which section to use for symbolic info. You can choose to
4457 control the decision manually, using overlay commands, or implement
4458 additional target-side support and use "overlay load-target" to bring
4459 in the overlay mapping. Do "help overlay" for more detail.
4463 The command "info symbol <address>" displays information about
4464 the symbol at the specified address.
4468 The standard remote protocol now includes an extension that allows
4469 asynchronous collection and display of trace data. This requires
4470 extensive support in the target-side debugging stub. Tracing mode
4471 includes a new interaction mode in GDB and new commands: see the
4472 file tracepoint.c for more details.
4476 Configurations for embedded MIPS now include a simulator contributed
4477 by Cygnus Solutions. The simulator supports the instruction sets
4478 of most MIPS variants.
4482 Sparc configurations may now include the ERC32 simulator contributed
4483 by the European Space Agency. The simulator is not built into
4484 Sparc targets by default; configure with --enable-sim to include it.
4488 For target configurations that may include multiple variants of a
4489 basic architecture (such as MIPS and SH), you may now set the
4490 architecture explicitly. "set arch" sets, "info arch" lists
4491 the possible architectures.
4493 *** Changes in GDB-4.16:
4495 * New native configurations
4497 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4498 M68K NetBSD m68k-*-netbsd*
4499 PowerPC AIX 4.x powerpc-*-aix*
4500 PowerPC MacOS powerpc-*-macos*
4501 PowerPC Windows NT powerpcle-*-cygwin32
4502 RS/6000 AIX 4.x rs6000-*-aix4*
4506 ARM with RDP protocol arm-*-*
4507 I960 with MON960 i960-*-coff
4508 MIPS VxWorks mips*-*-vxworks*
4509 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4510 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4512 Matra Sparclet sparclet-*-*
4516 The powerpc-eabi configuration now includes the PSIM simulator,
4517 contributed by Andrew Cagney, with assistance from Mike Meissner.
4518 PSIM is a very elaborate model of the PowerPC, including not only
4519 basic instruction set execution, but also details of execution unit
4520 performance and I/O hardware. See sim/ppc/README for more details.
4524 GDB now works with Solaris 2.5.
4526 * Windows 95/NT native
4528 GDB will now work as a native debugger on Windows 95 and Windows NT.
4529 To build it from source, you must use the "gnu-win32" environment,
4530 which uses a DLL to emulate enough of Unix to run the GNU tools.
4531 Further information, binaries, and sources are available at
4532 ftp.cygnus.com, under pub/gnu-win32.
4534 * dont-repeat command
4536 If a user-defined command includes the command `dont-repeat', then the
4537 command will not be repeated if the user just types return. This is
4538 useful if the command is time-consuming to run, so that accidental
4539 extra keystrokes don't run the same command many times.
4541 * Send break instead of ^C
4543 The standard remote protocol now includes an option to send a break
4544 rather than a ^C to the target in order to interrupt it. By default,
4545 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4547 * Remote protocol timeout
4549 The standard remote protocol includes a new variable `remotetimeout'
4550 that allows you to set the number of seconds before GDB gives up trying
4551 to read from the target. The default value is 2.
4553 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4555 By default GDB will automatically keep track of objects as they are
4556 loaded and unloaded by the dynamic linker. By using the command `set
4557 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4558 when shared library events occur, thus allowing you to set breakpoints
4559 in shared libraries which are explicitly loaded by the inferior.
4561 Note this feature does not work on hpux8. On hpux9 you must link
4562 /usr/lib/end.o into your program. This feature should work
4563 automatically on hpux10.
4565 * Irix 5.x hardware watchpoint support
4567 Irix 5 configurations now support the use of hardware watchpoints.
4569 * Mips protocol "SYN garbage limit"
4571 When debugging a Mips target using the `target mips' protocol, you
4572 may set the number of characters that GDB will ignore by setting
4573 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4574 every character. The default value is 1050.
4576 * Recording and replaying remote debug sessions
4578 If you set `remotelogfile' to the name of a file, gdb will write to it
4579 a recording of a remote debug session. This recording may then be
4580 replayed back to gdb using "gdbreplay". See gdbserver/README for
4581 details. This is useful when you have a problem with GDB while doing
4582 remote debugging; you can make a recording of the session and send it
4583 to someone else, who can then recreate the problem.
4585 * Speedups for remote debugging
4587 GDB includes speedups for downloading and stepping MIPS systems using
4588 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4589 and more efficient S-record downloading.
4591 * Memory use reductions and statistics collection
4593 GDB now uses less memory and reports statistics about memory usage.
4594 Try the `maint print statistics' command, for example.
4596 *** Changes in GDB-4.15:
4598 * Psymtabs for XCOFF
4600 The symbol reader for AIX GDB now uses partial symbol tables. This
4601 can greatly improve startup time, especially for large executables.
4603 * Remote targets use caching
4605 Remote targets now use a data cache to speed up communication with the
4606 remote side. The data cache could lead to incorrect results because
4607 it doesn't know about volatile variables, thus making it impossible to
4608 debug targets which use memory mapped I/O devices. `set remotecache
4609 off' turns the the data cache off.
4611 * Remote targets may have threads
4613 The standard remote protocol now includes support for multiple threads
4614 in the target system, using new protocol commands 'H' and 'T'. See
4615 gdb/remote.c for details.
4619 If GDB is configured with `--enable-netrom', then it will include
4620 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4621 acts as though it is a bank of ROM on the target board, but you can
4622 write into it over the network. GDB's support consists only of
4623 support for fast loading into the emulated ROM; to debug, you must use
4624 another protocol, such as standard remote protocol. The usual
4625 sequence is something like
4627 target nrom <netrom-hostname>
4629 target remote <netrom-hostname>:1235
4633 GDB now includes support for the Apple Macintosh, as a host only. It
4634 may be run as either an MPW tool or as a standalone application, and
4635 it can debug through the serial port. All the usual GDB commands are
4636 available, but to the target command, you must supply "serial" as the
4637 device type instead of "/dev/ttyXX". See mpw-README in the main
4638 directory for more information on how to build. The MPW configuration
4639 scripts */mpw-config.in support only a few targets, and only the
4640 mips-idt-ecoff target has been tested.
4644 GDB configuration now uses autoconf. This is not user-visible,
4645 but does simplify configuration and building.
4649 GDB now supports hpux10.
4651 *** Changes in GDB-4.14:
4653 * New native configurations
4655 x86 FreeBSD i[345]86-*-freebsd
4656 x86 NetBSD i[345]86-*-netbsd
4657 NS32k NetBSD ns32k-*-netbsd
4658 Sparc NetBSD sparc-*-netbsd
4662 A29K VxWorks a29k-*-vxworks
4663 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4664 CPU32 EST-300 emulator m68*-*-est*
4665 PowerPC ELF powerpc-*-elf
4668 * Alpha OSF/1 support for procfs
4670 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4671 possible to attach to running processes. As the mounting of the /proc
4672 filesystem is optional on the Alpha, GDB automatically determines
4673 the availability of /proc during startup. This can lead to problems
4674 if /proc is unmounted after GDB has been started.
4676 * Arguments to user-defined commands
4678 User commands may accept up to 10 arguments separated by whitespace.
4679 Arguments are accessed within the user command via $arg0..$arg9. A
4682 print $arg0 + $arg1 + $arg2
4684 To execute the command use:
4687 Defines the command "adder" which prints the sum of its three arguments.
4688 Note the arguments are text substitutions, so they may reference variables,
4689 use complex expressions, or even perform inferior function calls.
4691 * New `if' and `while' commands
4693 This makes it possible to write more sophisticated user-defined
4694 commands. Both commands take a single argument, which is the
4695 expression to evaluate, and must be followed by the commands to
4696 execute, one per line, if the expression is nonzero, the list being
4697 terminated by the word `end'. The `if' command list may include an
4698 `else' word, which causes the following commands to be executed only
4699 if the expression is zero.
4701 * Fortran source language mode
4703 GDB now includes partial support for Fortran 77. It will recognize
4704 Fortran programs and can evaluate a subset of Fortran expressions, but
4705 variables and functions may not be handled correctly. GDB will work
4706 with G77, but does not yet know much about symbols emitted by other
4709 * Better HPUX support
4711 Most debugging facilities now work on dynamic executables for HPPAs
4712 running hpux9 or later. You can attach to running dynamically linked
4713 processes, but by default the dynamic libraries will be read-only, so
4714 for instance you won't be able to put breakpoints in them. To change
4715 that behavior do the following before running the program:
4721 This will cause the libraries to be mapped private and read-write.
4722 To revert to the normal behavior, do this:
4728 You cannot set breakpoints or examine data in the library until after
4729 the library is loaded if the function/data symbols do not have
4732 GDB can now also read debug symbols produced by the HP C compiler on
4733 HPPAs (sorry, no C++, Fortran or 68k support).
4735 * Target byte order now dynamically selectable
4737 You can choose which byte order to use with a target system, via the
4738 commands "set endian big" and "set endian little", and you can see the
4739 current setting by using "show endian". You can also give the command
4740 "set endian auto", in which case GDB will use the byte order
4741 associated with the executable. Currently, only embedded MIPS
4742 configurations support dynamic selection of target byte order.
4744 * New DOS host serial code
4746 This version uses DPMI interrupts to handle buffered I/O, so you
4747 no longer need to run asynctsr when debugging boards connected to
4750 *** Changes in GDB-4.13:
4752 * New "complete" command
4754 This lists all the possible completions for the rest of the line, if it
4755 were to be given as a command itself. This is intended for use by emacs.
4757 * Trailing space optional in prompt
4759 "set prompt" no longer adds a space for you after the prompt you set. This
4760 allows you to set a prompt which ends in a space or one that does not.
4762 * Breakpoint hit counts
4764 "info break" now displays a count of the number of times the breakpoint
4765 has been hit. This is especially useful in conjunction with "ignore"; you
4766 can ignore a large number of breakpoint hits, look at the breakpoint info
4767 to see how many times the breakpoint was hit, then run again, ignoring one
4768 less than that number, and this will get you quickly to the last hit of
4771 * Ability to stop printing at NULL character
4773 "set print null-stop" will cause GDB to stop printing the characters of
4774 an array when the first NULL is encountered. This is useful when large
4775 arrays actually contain only short strings.
4777 * Shared library breakpoints
4779 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4780 breakpoints in shared libraries before the executable is run.
4782 * Hardware watchpoints
4784 There is a new hardware breakpoint for the watch command for sparclite
4785 targets. See gdb/sparclite/hw_breakpoint.note.
4787 Hardware watchpoints are also now supported under GNU/Linux.
4791 Annotations have been added. These are for use with graphical interfaces,
4792 and are still experimental. Currently only gdba.el uses these.
4794 * Improved Irix 5 support
4796 GDB now works properly with Irix 5.2.
4798 * Improved HPPA support
4800 GDB now works properly with the latest GCC and GAS.
4802 * New native configurations
4804 Sequent PTX4 i[34]86-sequent-ptx4
4805 HPPA running OSF/1 hppa*-*-osf*
4806 Atari TT running SVR4 m68*-*-sysv4*
4807 RS/6000 LynxOS rs6000-*-lynxos*
4811 OS/9000 i[34]86-*-os9k
4812 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4815 * Hitachi SH7000 and E7000-PC ICE support
4817 There is now support for communicating with the Hitachi E7000-PC ICE.
4818 This is available automatically when GDB is configured for the SH.
4822 As usual, a variety of small fixes and improvements, both generic
4823 and configuration-specific. See the ChangeLog for more detail.
4825 *** Changes in GDB-4.12:
4827 * Irix 5 is now supported
4831 GDB-4.12 on the HPPA has a number of changes which make it unable
4832 to debug the output from the currently released versions of GCC and
4833 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4834 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4835 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4838 *** Changes in GDB-4.11:
4840 * User visible changes:
4844 The "set remotedebug" option is now consistent between the mips remote
4845 target, remote targets using the gdb-specific protocol, UDI (AMD's
4846 debug protocol for the 29k) and the 88k bug monitor. It is now an
4847 integer specifying a debug level (normally 0 or 1, but 2 means more
4848 debugging info for the mips target).
4850 * DEC Alpha native support
4852 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4853 debug info, but GDB works fairly well with the DEC compiler and should
4854 work with a future GCC release. See the README file for a few
4855 Alpha-specific notes.
4857 * Preliminary thread implementation
4859 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4861 * LynxOS native and target support for 386
4863 This release has been hosted on LynxOS 2.2, and also can be configured
4864 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4867 * Improvements in C++ mangling/demangling.
4869 This release has much better g++ debugging, specifically in name
4870 mangling/demangling, virtual function calls, print virtual table,
4871 call methods, ...etc.
4873 *** Changes in GDB-4.10:
4875 * User visible changes:
4877 Remote debugging using the GDB-specific (`target remote') protocol now
4878 supports the `load' command. This is only useful if you have some
4879 other way of getting the stub to the target system, and you can put it
4880 somewhere in memory where it won't get clobbered by the download.
4882 Filename completion now works.
4884 When run under emacs mode, the "info line" command now causes the
4885 arrow to point to the line specified. Also, "info line" prints
4886 addresses in symbolic form (as well as hex).
4888 All vxworks based targets now support a user settable option, called
4889 vxworks-timeout. This option represents the number of seconds gdb
4890 should wait for responses to rpc's. You might want to use this if
4891 your vxworks target is, perhaps, a slow software simulator or happens
4892 to be on the far side of a thin network line.
4896 This release contains support for using a DEC alpha as a GDB host for
4897 cross debugging. Native alpha debugging is not supported yet.
4900 *** Changes in GDB-4.9:
4904 This is the first GDB release which is accompanied by a matching testsuite.
4905 The testsuite requires installation of dejagnu, which should be available
4906 via ftp from most sites that carry GNU software.
4910 'Cfront' style demangling has had its name changed to 'ARM' style, to
4911 emphasize that it was written from the specifications in the C++ Annotated
4912 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4913 disclaimers, it still generated too much confusion with users attempting to
4914 use gdb with AT&T cfront.
4918 GDB now uses a standard remote interface to a simulator library.
4919 So far, the library contains simulators for the Zilog Z8001/2, the
4920 Hitachi H8/300, H8/500 and Super-H.
4922 * New targets supported
4924 H8/300 simulator h8300-hitachi-hms or h8300hms
4925 H8/500 simulator h8500-hitachi-hms or h8500hms
4926 SH simulator sh-hitachi-hms or sh
4927 Z8000 simulator z8k-zilog-none or z8ksim
4928 IDT MIPS board over serial line mips-idt-ecoff
4930 Cross-debugging to GO32 targets is supported. It requires a custom
4931 version of the i386-stub.c module which is integrated with the
4932 GO32 memory extender.
4934 * New remote protocols
4936 MIPS remote debugging protocol.
4938 * New source languages supported
4940 This version includes preliminary support for Chill, a Pascal like language
4941 used by telecommunications companies. Chill support is also being integrated
4942 into the GNU compiler, but we don't know when it will be publically available.
4945 *** Changes in GDB-4.8:
4947 * HP Precision Architecture supported
4949 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4950 version of this support was available as a set of patches from the
4951 University of Utah. GDB does not support debugging of programs
4952 compiled with the HP compiler, because HP will not document their file
4953 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4954 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4956 Many problems in the preliminary version have been fixed.
4958 * Faster and better demangling
4960 We have improved template demangling and fixed numerous bugs in the GNU style
4961 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4962 character types (wchar_t) are now supported. Demangling of each symbol is now
4963 only done once, and is cached when the symbol table for a file is read in.
4964 This results in a small increase in memory usage for C programs, a moderate
4965 increase in memory usage for C++ programs, and a fantastic speedup in
4968 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4969 from the specifications in the Annotated Reference Manual, which AT&T's
4970 compiler does not actually implement.
4972 * G++ multiple inheritance compiler problem
4974 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4975 inheritance lattices was reworked to properly discover ambiguities. We
4976 recently found an example which causes this new algorithm to fail in a
4977 very subtle way, producing bad debug information for those classes.
4978 The file 'gcc.patch' (in this directory) can be applied to gcc to
4979 circumvent the problem. A future GCC release will contain a complete
4982 The previous G++ debug info problem (mentioned below for the gdb-4.7
4983 release) is fixed in gcc version 2.3.2.
4985 * Improved configure script
4987 The `configure' script will now attempt to guess your system type if
4988 you don't supply a host system type. The old scheme of supplying a
4989 host system triplet is preferable over using this. All the magic is
4990 done in the new `config.guess' script. Examine it for details.
4992 We have also brought our configure script much more in line with the FSF's
4993 version. It now supports the --with-xxx options. In particular,
4994 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4995 The resulting GDB will not be able to read arbitrary object file formats --
4996 only the format ``expected'' to be used on the configured target system.
4997 We hope to make this the default in a future release.
4999 * Documentation improvements
5001 There's new internal documentation on how to modify GDB, and how to
5002 produce clean changes to the code. We implore people to read it
5003 before submitting changes.
5005 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5006 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5007 `info' files are also provided. To build `info' files from scratch,
5008 you will need the latest `makeinfo' release, which will be available in
5009 a future texinfo-X.Y release.
5011 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5012 We're not sure exactly which versions have this problem, but it has
5013 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5014 or better. If that isn't possible, there is a patch in
5015 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5016 around this problem.
5020 GDB now supports array constants that can be used in expressions typed in by
5021 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5022 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5025 The new directory `gdb/sparclite' contains a program that demonstrates
5026 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5028 * New native hosts supported
5030 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5031 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5033 * New targets supported
5035 AMD 29k family via UDI a29k-amd-udi or udi29k
5037 * New file formats supported
5039 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5040 HPUX core files, and SCO 3.2v2 core files.
5044 Attaching to processes now works again; thanks for the many bug reports.
5046 We have also stomped on a bunch of core dumps caused by
5047 printf_filtered("%s") problems.
5049 We eliminated a copyright problem on the rpc and ptrace header files
5050 for VxWorks, which was discovered at the last minute during the 4.7
5051 release. You should now be able to build a VxWorks GDB.
5053 You can now interrupt gdb while an attached process is running. This
5054 will cause the attached process to stop, and give control back to GDB.
5056 We fixed problems caused by using too many file descriptors
5057 for reading symbols from object files and libraries. This was
5058 especially a problem for programs that used many (~100) shared
5061 The `step' command now only enters a subroutine if there is line number
5062 information for the subroutine. Otherwise it acts like the `next'
5063 command. Previously, `step' would enter subroutines if there was
5064 any debugging information about the routine. This avoids problems
5065 when using `cc -g1' on MIPS machines.
5067 * Internal improvements
5069 GDB's internal interfaces have been improved to make it easier to support
5070 debugging of multiple languages in the future.
5072 GDB now uses a common structure for symbol information internally.
5073 Minimal symbols (derived from linkage symbols in object files), partial
5074 symbols (from a quick scan of debug information), and full symbols
5075 contain a common subset of information, making it easier to write
5076 shared code that handles any of them.
5078 * New command line options
5080 We now accept --silent as an alias for --quiet.
5084 The memory-mapped-malloc library is now licensed under the GNU Library
5085 General Public License.
5087 *** Changes in GDB-4.7:
5089 * Host/native/target split
5091 GDB has had some major internal surgery to untangle the support for
5092 hosts and remote targets. Now, when you configure GDB for a remote
5093 target, it will no longer load in all of the support for debugging
5094 local programs on the host. When fully completed and tested, this will
5095 ensure that arbitrary host/target combinations are possible.
5097 The primary conceptual shift is to separate the non-portable code in
5098 GDB into three categories. Host specific code is required any time GDB
5099 is compiled on that host, regardless of the target. Target specific
5100 code relates to the peculiarities of the target, but can be compiled on
5101 any host. Native specific code is everything else: it can only be
5102 built when the host and target are the same system. Child process
5103 handling and core file support are two common `native' examples.
5105 GDB's use of /proc for controlling Unix child processes is now cleaner.
5106 It has been split out into a single module under the `target_ops' vector,
5107 plus two native-dependent functions for each system that uses /proc.
5109 * New hosts supported
5111 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5112 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5113 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5115 * New targets supported
5117 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5118 68030 and CPU32 m68030-*-*, m68332-*-*
5120 * New native hosts supported
5122 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5123 (386bsd is not well tested yet)
5124 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5126 * New file formats supported
5128 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5129 supports reading of `a.out.adobe' object files, which are an a.out
5130 format extended with minimal information about multiple sections.
5134 `show copying' is the same as the old `info copying'.
5135 `show warranty' is the same as `info warrantee'.
5136 These were renamed for consistency. The old commands continue to work.
5138 `info handle' is a new alias for `info signals'.
5140 You can now define pre-command hooks, which attach arbitrary command
5141 scripts to any command. The commands in the hook will be executed
5142 prior to the user's command. You can also create a hook which will be
5143 executed whenever the program stops. See gdb.texinfo.
5147 We now deal with Cfront style name mangling, and can even extract type
5148 info from mangled symbols. GDB can automatically figure out which
5149 symbol mangling style your C++ compiler uses.
5151 Calling of methods and virtual functions has been improved as well.
5155 The crash that occured when debugging Sun Ansi-C compiled binaries is
5156 fixed. This was due to mishandling of the extra N_SO stabs output
5159 We also finally got Ultrix 4.2 running in house, and fixed core file
5160 support, with help from a dozen people on the net.
5162 John M. Farrell discovered that the reason that single-stepping was so
5163 slow on all of the Mips based platforms (primarily SGI and DEC) was
5164 that we were trying to demangle and lookup a symbol used for internal
5165 purposes on every instruction that was being stepped through. Changing
5166 the name of that symbol so that it couldn't be mistaken for a C++
5167 mangled symbol sped things up a great deal.
5169 Rich Pixley sped up symbol lookups in general by getting much smarter
5170 about when C++ symbol mangling is necessary. This should make symbol
5171 completion (TAB on the command line) much faster. It's not as fast as
5172 we'd like, but it's significantly faster than gdb-4.6.
5176 A new user controllable variable 'call_scratch_address' can
5177 specify the location of a scratch area to be used when GDB
5178 calls a function in the target. This is necessary because the
5179 usual method of putting the scratch area on the stack does not work
5180 in systems that have separate instruction and data spaces.
5182 We integrated changes to support the 29k UDI (Universal Debugger
5183 Interface), but discovered at the last minute that we didn't have all
5184 of the appropriate copyright paperwork. We are working with AMD to
5185 resolve this, and hope to have it available soon.
5189 We have sped up the remote serial line protocol, especially for targets
5190 with lots of registers. It now supports a new `expedited status' ('T')
5191 message which can be used in place of the existing 'S' status message.
5192 This allows the remote stub to send only the registers that GDB
5193 needs to make a quick decision about single-stepping or conditional
5194 breakpoints, eliminating the need to fetch the entire register set for
5195 each instruction being stepped through.
5197 The GDB remote serial protocol now implements a write-through cache for
5198 registers, only re-reading the registers if the target has run.
5200 There is also a new remote serial stub for SPARC processors. You can
5201 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5202 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5203 processor with a serial port.
5207 Configure.in files have become much easier to read and modify. A new
5208 `table driven' format makes it more obvious what configurations are
5209 supported, and what files each one uses.
5213 There is a new opcodes library which will eventually contain all of the
5214 disassembly routines and opcode tables. At present, it only contains
5215 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5216 disassembler (binutils/objdump) to share these routines.
5218 The libiberty library is now copylefted under the GNU Library General
5219 Public License. This allows more liberal use, and was done so libg++
5220 can use it. This makes no difference to GDB, since the Library License
5221 grants all the rights from the General Public License.
5225 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5226 reference to the stabs symbol info used by the debugger. It is (as far
5227 as we know) the only published document on this fascinating topic. We
5228 encourage you to read it, compare it to the stabs information on your
5229 system, and send improvements on the document in general (to
5230 bug-gdb@prep.ai.mit.edu).
5232 And, of course, many bugs have been fixed.
5235 *** Changes in GDB-4.6:
5237 * Better support for C++ function names
5239 GDB now accepts as input the "demangled form" of C++ overloaded function
5240 names and member function names, and can do command completion on such names
5241 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5242 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5243 Make use of command completion, it is your friend.
5245 GDB also now accepts a variety of C++ mangled symbol formats. They are
5246 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5247 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5248 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5249 for the list of formats.
5251 * G++ symbol mangling problem
5253 Recent versions of gcc have a bug in how they emit debugging information for
5254 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5255 directory) can be applied to gcc to fix the problem. Alternatively, if you
5256 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5257 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5258 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5261 * New 'maintenance' command
5263 All of the commands related to hacking GDB internals have been moved out of
5264 the main command set, and now live behind the 'maintenance' command. This
5265 can also be abbreviated as 'mt'. The following changes were made:
5267 dump-me -> maintenance dump-me
5268 info all-breakpoints -> maintenance info breakpoints
5269 printmsyms -> maintenance print msyms
5270 printobjfiles -> maintenance print objfiles
5271 printpsyms -> maintenance print psymbols
5272 printsyms -> maintenance print symbols
5274 The following commands are new:
5276 maintenance demangle Call internal GDB demangler routine to
5277 demangle a C++ link name and prints the result.
5278 maintenance print type Print a type chain for a given symbol
5280 * Change to .gdbinit file processing
5282 We now read the $HOME/.gdbinit file before processing the argv arguments
5283 (e.g. reading symbol files or core files). This allows global parameters to
5284 be set, which will apply during the symbol reading. The ./.gdbinit is still
5285 read after argv processing.
5287 * New hosts supported
5289 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5291 GNU/Linux support i386-unknown-linux or linux
5293 We are also including code to support the HP/PA running BSD and HPUX. This
5294 is almost guaranteed not to work, as we didn't have time to test or build it
5295 for this release. We are including it so that the more adventurous (or
5296 masochistic) of you can play with it. We also had major problems with the
5297 fact that the compiler that we got from HP doesn't support the -g option.
5300 * New targets supported
5302 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5304 * More smarts about finding #include files
5306 GDB now remembers the compilation directory for all include files, and for
5307 all files from which C is generated (like yacc and lex sources). This
5308 greatly improves GDB's ability to find yacc/lex sources, and include files,
5309 especially if you are debugging your program from a directory different from
5310 the one that contains your sources.
5312 We also fixed a bug which caused difficulty with listing and setting
5313 breakpoints in include files which contain C code. (In the past, you had to
5314 try twice in order to list an include file that you hadn't looked at before.)
5316 * Interesting infernals change
5318 GDB now deals with arbitrary numbers of sections, where the symbols for each
5319 section must be relocated relative to that section's landing place in the
5320 target's address space. This work was needed to support ELF with embedded
5321 stabs used by Solaris-2.0.
5323 * Bug fixes (of course!)
5325 There have been loads of fixes for the following things:
5326 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5327 i960, stabs, DOS(GO32), procfs, etc...
5329 See the ChangeLog for details.
5331 *** Changes in GDB-4.5:
5333 * New machines supported (host and target)
5335 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5337 SGI Irix-4.x mips-sgi-irix4 or iris4
5339 * New malloc package
5341 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5342 Mmalloc is capable of handling mutiple heaps of memory. It is also
5343 capable of saving a heap to a file, and then mapping it back in later.
5344 This can be used to greatly speedup the startup of GDB by using a
5345 pre-parsed symbol table which lives in a mmalloc managed heap. For
5346 more details, please read mmalloc/mmalloc.texi.
5350 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5351 'help info proc' for details.
5353 * MIPS ecoff symbol table format
5355 The code that reads MIPS symbol table format is now supported on all hosts.
5356 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5359 * File name changes for MS-DOS
5361 Many files in the config directories have been renamed to make it easier to
5362 support GDB on MS-DOSe systems (which have very restrictive file name
5363 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5364 environment) is close to working but has some remaining problems. Note
5365 that debugging of DOS programs is not supported, due to limitations
5366 in the ``operating system'', but it can be used to host cross-debugging.
5368 * Cross byte order fixes
5370 Many fixes have been made to support cross debugging of Sparc and MIPS
5371 targets from hosts whose byte order differs.
5373 * New -mapped and -readnow options
5375 If memory-mapped files are available on your system through the 'mmap'
5376 system call, you can use the -mapped option on the `file' or
5377 `symbol-file' commands to cause GDB to write the symbols from your
5378 program into a reusable file. If the program you are debugging is
5379 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5380 Future GDB debugging sessions will notice the presence of this file,
5381 and will quickly map in symbol information from it, rather than reading
5382 the symbol table from the executable program. Using the '-mapped'
5383 option in a GDB `file' or `symbol-file' command has the same effect as
5384 starting GDB with the '-mapped' command-line option.
5386 You can cause GDB to read the entire symbol table immediately by using
5387 the '-readnow' option with any of the commands that load symbol table
5388 information (or on the GDB command line). This makes the command
5389 slower, but makes future operations faster.
5391 The -mapped and -readnow options are typically combined in order to
5392 build a `fred.syms' file that contains complete symbol information.
5393 A simple GDB invocation to do nothing but build a `.syms' file for future
5396 gdb -batch -nx -mapped -readnow programname
5398 The `.syms' file is specific to the host machine on which GDB is run.
5399 It holds an exact image of GDB's internal symbol table. It cannot be
5400 shared across multiple host platforms.
5402 * longjmp() handling
5404 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5405 siglongjmp() without losing control. This feature has not yet been ported to
5406 all systems. It currently works on many 386 platforms, all MIPS-based
5407 platforms (SGI, DECstation, etc), and Sun3/4.
5411 Preliminary work has been put in to support the new Solaris OS from Sun. At
5412 this time, it can control and debug processes, but it is not capable of
5417 As always, many many bug fixes. The major areas were with g++, and mipsread.
5418 People using the MIPS-based platforms should experience fewer mysterious
5419 crashes and trashed symbol tables.
5421 *** Changes in GDB-4.4:
5423 * New machines supported (host and target)
5425 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5427 BSD Reno on Vax vax-dec-bsd
5428 Ultrix on Vax vax-dec-ultrix
5430 * New machines supported (target)
5432 AMD 29000 embedded, using EBMON a29k-none-none
5436 GDB continues to improve its handling of C++. `References' work better.
5437 The demangler has also been improved, and now deals with symbols mangled as
5438 per the Annotated C++ Reference Guide.
5440 GDB also now handles `stabs' symbol information embedded in MIPS
5441 `ecoff' symbol tables. Since the ecoff format was not easily
5442 extensible to handle new languages such as C++, this appeared to be a
5443 good way to put C++ debugging info into MIPS binaries. This option
5444 will be supported in the GNU C compiler, version 2, when it is
5447 * New features for SVR4
5449 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5450 shared libraries. Debugging dynamically linked programs should present
5451 only minor differences from debugging statically linked programs.
5453 The `info proc' command will print out information about any process
5454 on an SVR4 system (including the one you are debugging). At the moment,
5455 it prints the address mappings of the process.
5457 If you bring up GDB on another SVR4 system, please send mail to
5458 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5460 * Better dynamic linking support in SunOS
5462 Reading symbols from shared libraries which contain debugging symbols
5463 now works properly. However, there remain issues such as automatic
5464 skipping of `transfer vector' code during function calls, which
5465 make it harder to debug code in a shared library, than to debug the
5466 same code linked statically.
5470 GDB is now using the latest `getopt' routines from the FSF. This
5471 version accepts the -- prefix for options with long names. GDB will
5472 continue to accept the old forms (-option and +option) as well.
5473 Various single letter abbreviations for options have been explicity
5474 added to the option table so that they won't get overshadowed in the
5475 future by other options that begin with the same letter.
5479 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5480 Many assorted bugs have been handled. Many more remain to be handled.
5481 See the various ChangeLog files (primarily in gdb and bfd) for details.
5484 *** Changes in GDB-4.3:
5486 * New machines supported (host and target)
5488 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5489 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5490 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5492 * Almost SCO Unix support
5494 We had hoped to support:
5495 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5496 (except for core file support), but we discovered very late in the release
5497 that it has problems with process groups that render gdb unusable. Sorry
5498 about that. I encourage people to fix it and post the fixes.
5500 * Preliminary ELF and DWARF support
5502 GDB can read ELF object files on System V Release 4, and can handle
5503 debugging records for C, in DWARF format, in ELF files. This support
5504 is preliminary. If you bring up GDB on another SVR4 system, please
5505 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5510 GDB now uses the latest `readline' library. One user-visible change
5511 is that two tabs will list possible command completions, which previously
5512 required typing M-? (meta-question mark, or ESC ?).
5516 The `stepi' bug that many of you noticed has been squashed.
5517 Many bugs in C++ have been handled. Many more remain to be handled.
5518 See the various ChangeLog files (primarily in gdb and bfd) for details.
5520 * State of the MIPS world (in case you wondered):
5522 GDB can understand the symbol tables emitted by the compilers
5523 supplied by most vendors of MIPS-based machines, including DEC. These
5524 symbol tables are in a format that essentially nobody else uses.
5526 Some versions of gcc come with an assembler post-processor called
5527 mips-tfile. This program is required if you want to do source-level
5528 debugging of gcc-compiled programs. I believe FSF does not ship
5529 mips-tfile with gcc version 1, but it will eventually come with gcc
5532 Debugging of g++ output remains a problem. g++ version 1.xx does not
5533 really support it at all. (If you're lucky, you should be able to get
5534 line numbers and stack traces to work, but no parameters or local
5535 variables.) With some work it should be possible to improve the
5538 When gcc version 2 is released, you will have somewhat better luck.
5539 However, even then you will get confusing results for inheritance and
5542 We will eventually provide full debugging of g++ output on
5543 DECstations. This will probably involve some kind of stabs-in-ecoff
5544 encapulation, but the details have not been worked out yet.
5547 *** Changes in GDB-4.2:
5549 * Improved configuration
5551 Only one copy of `configure' exists now, and it is not self-modifying.
5552 Porting BFD is simpler.
5556 The `step' and `next' commands now only stop at the first instruction
5557 of a source line. This prevents the multiple stops that used to occur
5558 in switch statements, for-loops, etc. `Step' continues to stop if a
5559 function that has debugging information is called within the line.
5563 Lots of small bugs fixed. More remain.
5565 * New host supported (not target)
5567 Intel 386 PC clone running Mach i386-none-mach
5570 *** Changes in GDB-4.1:
5572 * Multiple source language support
5574 GDB now has internal scaffolding to handle several source languages.
5575 It determines the type of each source file from its filename extension,
5576 and will switch expression parsing and number formatting to match the
5577 language of the function in the currently selected stack frame.
5578 You can also specifically set the language to be used, with
5579 `set language c' or `set language modula-2'.
5583 GDB now has preliminary support for the GNU Modula-2 compiler,
5584 currently under development at the State University of New York at
5585 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5586 continue through the fall of 1991 and into 1992.
5588 Other Modula-2 compilers are currently not supported, and attempting to
5589 debug programs compiled with them will likely result in an error as the
5590 symbol table is read. Feel free to work on it, though!
5592 There are hooks in GDB for strict type checking and range checking,
5593 in the `Modula-2 philosophy', but they do not currently work.
5597 GDB can now write to executable and core files (e.g. patch
5598 a variable's value). You must turn this switch on, specify
5599 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5600 by assigning a new value to a variable. Modifications take
5603 * Automatic SunOS shared library reading
5605 When you run your program, GDB automatically determines where its
5606 shared libraries (if any) have been loaded, and reads their symbols.
5607 The `share' command is no longer needed. This also works when
5608 examining core files.
5612 You can specify the number of lines that the `list' command shows.
5615 * New machines supported (host and target)
5617 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5618 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5619 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5621 * New hosts supported (not targets)
5623 IBM RT/PC: romp-ibm-aix or rtpc
5625 * New targets supported (not hosts)
5627 AMD 29000 embedded with COFF a29k-none-coff
5628 AMD 29000 embedded with a.out a29k-none-aout
5629 Ultracomputer remote kernel debug a29k-nyu-kern
5631 * New remote interfaces
5637 *** Changes in GDB-4.0:
5641 Wide output is wrapped at good places to make the output more readable.
5643 Gdb now supports cross-debugging from a host machine of one type to a
5644 target machine of another type. Communication with the target system
5645 is over serial lines. The ``target'' command handles connecting to the
5646 remote system; the ``load'' command will download a program into the
5647 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5648 also supports debugging of realtime processes running under VxWorks,
5649 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5650 stub on the target system.
5652 New CPUs supported include the AMD 29000 and Intel 960.
5654 GDB now reads object files and symbol tables via a ``binary file''
5655 library, which allows a single copy of GDB to debug programs of multiple
5656 object file types such as a.out and coff.
5658 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5659 refcard.dvi and refcard.ps are available to format it).
5662 * Control-Variable user interface simplified
5664 All variables that control the operation of the debugger can be set
5665 by the ``set'' command, and displayed by the ``show'' command.
5667 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5668 ``Show prompt'' produces the response:
5669 Gdb's prompt is new-gdb=>.
5671 What follows are the NEW set commands. The command ``help set'' will
5672 print a complete list of old and new set commands. ``help set FOO''
5673 will give a longer description of the variable FOO. ``show'' will show
5674 all of the variable descriptions and their current settings.
5676 confirm on/off: Enables warning questions for operations that are
5677 hard to recover from, e.g. rerunning the program while
5678 it is already running. Default is ON.
5680 editing on/off: Enables EMACS style command line editing
5681 of input. Previous lines can be recalled with
5682 control-P, the current line can be edited with control-B,
5683 you can search for commands with control-R, etc.
5686 history filename NAME: NAME is where the gdb command history
5687 will be stored. The default is .gdb_history,
5688 or the value of the environment variable
5691 history size N: The size, in commands, of the command history. The
5692 default is 256, or the value of the environment variable
5695 history save on/off: If this value is set to ON, the history file will
5696 be saved after exiting gdb. If set to OFF, the
5697 file will not be saved. The default is OFF.
5699 history expansion on/off: If this value is set to ON, then csh-like
5700 history expansion will be performed on
5701 command line input. The default is OFF.
5703 radix N: Sets the default radix for input and output. It can be set
5704 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5705 in the current radix, so "set radix 10" is always a no-op.
5707 height N: This integer value is the number of lines on a page. Default
5708 is 24, the current `stty rows'' setting, or the ``li#''
5709 setting from the termcap entry matching the environment
5712 width N: This integer value is the number of characters on a line.
5713 Default is 80, the current `stty cols'' setting, or the ``co#''
5714 setting from the termcap entry matching the environment
5717 Note: ``set screensize'' is obsolete. Use ``set height'' and
5718 ``set width'' instead.
5720 print address on/off: Print memory addresses in various command displays,
5721 such as stack traces and structure values. Gdb looks
5722 more ``symbolic'' if you turn this off; it looks more
5723 ``machine level'' with it on. Default is ON.
5725 print array on/off: Prettyprint arrays. New convenient format! Default
5728 print demangle on/off: Print C++ symbols in "source" form if on,
5731 print asm-demangle on/off: Same, for assembler level printouts
5734 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5737 * Support for Epoch Environment.
5739 The epoch environment is a version of Emacs v18 with windowing. One
5740 new command, ``inspect'', is identical to ``print'', except that if you
5741 are running in the epoch environment, the value is printed in its own
5745 * Support for Shared Libraries
5747 GDB can now debug programs and core files that use SunOS shared libraries.
5748 Symbols from a shared library cannot be referenced
5749 before the shared library has been linked with the program (this
5750 happens after you type ``run'' and before the function main() is entered).
5751 At any time after this linking (including when examining core files
5752 from dynamically linked programs), gdb reads the symbols from each
5753 shared library when you type the ``sharedlibrary'' command.
5754 It can be abbreviated ``share''.
5756 sharedlibrary REGEXP: Load shared object library symbols for files
5757 matching a unix regular expression. No argument
5758 indicates to load symbols for all shared libraries.
5760 info sharedlibrary: Status of loaded shared libraries.
5765 A watchpoint stops execution of a program whenever the value of an
5766 expression changes. Checking for this slows down execution
5767 tremendously whenever you are in the scope of the expression, but is
5768 quite useful for catching tough ``bit-spreader'' or pointer misuse
5769 problems. Some machines such as the 386 have hardware for doing this
5770 more quickly, and future versions of gdb will use this hardware.
5772 watch EXP: Set a watchpoint (breakpoint) for an expression.
5774 info watchpoints: Information about your watchpoints.
5776 delete N: Deletes watchpoint number N (same as breakpoints).
5777 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5778 enable N: Re-enables watchpoint number N (same as breakpoints).
5781 * C++ multiple inheritance
5783 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5786 * C++ exception handling
5788 Gdb now supports limited C++ exception handling. Besides the existing
5789 ability to breakpoint on an exception handler, gdb can breakpoint on
5790 the raising of an exception (before the stack is peeled back to the
5793 catch FOO: If there is a FOO exception handler in the dynamic scope,
5794 set a breakpoint to catch exceptions which may be raised there.
5795 Multiple exceptions (``catch foo bar baz'') may be caught.
5797 info catch: Lists all exceptions which may be caught in the
5798 current stack frame.
5801 * Minor command changes
5803 The command ``call func (arg, arg, ...)'' now acts like the print
5804 command, except it does not print or save a value if the function's result
5805 is void. This is similar to dbx usage.
5807 The ``up'' and ``down'' commands now always print the frame they end up
5808 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5809 frames without printing.
5811 * New directory command
5813 'dir' now adds directories to the FRONT of the source search path.
5814 The path starts off empty. Source files that contain debug information
5815 about the directory in which they were compiled can be found even
5816 with an empty path; Sun CC and GCC include this information. If GDB can't
5817 find your source file in the current directory, type "dir .".
5819 * Configuring GDB for compilation
5821 For normal use, type ``./configure host''. See README or gdb.texinfo
5824 GDB now handles cross debugging. If you are remotely debugging between
5825 two different machines, type ``./configure host -target=targ''.
5826 Host is the machine where GDB will run; targ is the machine
5827 where the program that you are debugging will run.